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Islam MT, Cai J, Allen S, Moreno DG, Bloom SI, Bramwell RC, Mitton J, Horn AG, Zhu W, Donato AJ, Holland WL, Lesniewski LA. Endothelial-Specific Reduction in Arf6 Impairs Insulin-Stimulated Vasodilation and Skeletal Muscle Blood Flow Resulting in Systemic Insulin Resistance in Mice. Arterioscler Thromb Vasc Biol 2024; 44:1101-1113. [PMID: 38545783 DOI: 10.1161/atvbaha.123.319375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 02/27/2024] [Indexed: 04/09/2024]
Abstract
BACKGROUND Much of what we know about insulin resistance is based on studies from metabolically active tissues such as the liver, adipose tissue, and skeletal muscle. Emerging evidence suggests that the vascular endothelium plays a crucial role in systemic insulin resistance; however, the underlying mechanisms remain incompletely understood. Arf6 (ADP ribosylation factor 6) is a small GTPase that plays a critical role in endothelial cell function. Here, we tested the hypothesis that the deletion of endothelial Arf6 will result in systemic insulin resistance. METHODS We used mouse models of constitutive endothelial cell-specific Arf6 deletion (Arf6f/- Tie2Cre+) and tamoxifen-inducible Arf6 knockout (Arf6f/f Cdh5CreER+). Endothelium-dependent vasodilation was assessed using pressure myography. Metabolic function was assessed using a battery of metabolic assessments including glucose and insulin tolerance tests and hyperinsulinemic-euglycemic clamps. We used a fluorescence microsphere-based technique to measure tissue blood flow. Skeletal muscle capillary density was assessed using intravital microscopy. RESULTS Endothelial Arf6 deletion impaired insulin-stimulated vasodilation in white adipose tissue and skeletal muscle feed arteries. The impairment in vasodilation was primarily due to attenuated insulin-stimulated nitric oxide bioavailability but independent of altered acetylcholine-mediated or sodium nitroprusside-mediated vasodilation. Endothelial cell-specific deletion of Arf6 also resulted in systematic insulin resistance in normal chow-fed mice and glucose intolerance in high-fat diet-fed obese mice. The underlying mechanisms of glucose intolerance were reductions in insulin-stimulated blood flow and glucose uptake in the skeletal muscle and were independent of changes in capillary density or vascular permeability. CONCLUSIONS Results from this study support the conclusion that endothelial Arf6 signaling is essential for maintaining insulin sensitivity. Reduced expression of endothelial Arf6 impairs insulin-mediated vasodilation and results in systemic insulin resistance. These results have therapeutic implications for diseases that are associated with endothelial cell dysfunction and insulin resistance such as diabetes.
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Affiliation(s)
- Md Torikul Islam
- Department of Nutrition and Integrative Physiology (M.T.I., S.I.B., A.J.D., W.L.H., L.A.L.), The University of Utah, Salt Lake City
| | - Jinjin Cai
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
| | - Shanena Allen
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
| | - Denisse G Moreno
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
| | - Samuel I Bloom
- Department of Nutrition and Integrative Physiology (M.T.I., S.I.B., A.J.D., W.L.H., L.A.L.), The University of Utah, Salt Lake City
| | - R Colton Bramwell
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
| | - Jonathan Mitton
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
| | - Andrew G Horn
- Department of Kinesiology, Kansas State University, Manhattan (A.G.H.)
| | - Weiquan Zhu
- Division of Cardiovascular Medicine, Department of Internal Medicine (W.Z.), The University of Utah, Salt Lake City
- Department of Pathology (W.Z.), The University of Utah, Salt Lake City
- Program of Molecular Medicine (W.Z.), The University of Utah, Salt Lake City
| | - Anthony J Donato
- Department of Nutrition and Integrative Physiology (M.T.I., S.I.B., A.J.D., W.L.H., L.A.L.), The University of Utah, Salt Lake City
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
- Department of Biochemistry (A.J.D.), The University of Utah, Salt Lake City
- Nora Eccles Harrison Cardiovascular Research and Training Institute (A.J.D., L.A.L.), The University of Utah, Salt Lake City
- Veteran's Affairs Medical Center-Salt Lake City, Geriatric Research and Clinical Center, UT (A.J.D., L.A.L.)
| | - William L Holland
- Department of Nutrition and Integrative Physiology (M.T.I., S.I.B., A.J.D., W.L.H., L.A.L.), The University of Utah, Salt Lake City
| | - Lisa A Lesniewski
- Department of Nutrition and Integrative Physiology (M.T.I., S.I.B., A.J.D., W.L.H., L.A.L.), The University of Utah, Salt Lake City
- Division of Geriatrics, Department of Internal Medicine (J.C., S.A., D.G.M., R.C.B., J.M., A.J.D., L.A.L.), The University of Utah, Salt Lake City
- Nora Eccles Harrison Cardiovascular Research and Training Institute (A.J.D., L.A.L.), The University of Utah, Salt Lake City
- Veteran's Affairs Medical Center-Salt Lake City, Geriatric Research and Clinical Center, UT (A.J.D., L.A.L.)
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Ajan A, Roberg K, Fredriksson I, Abtahi J. Reproducibility of Laser Doppler Flowmetry in gingival microcirculation. A study on six different protocols. Microvasc Res 2024; 153:104666. [PMID: 38301938 DOI: 10.1016/j.mvr.2024.104666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 01/13/2024] [Accepted: 01/25/2024] [Indexed: 02/03/2024]
Abstract
OBJECTIVES Laser Doppler Flowmetry (LDF) is a non-invasive technique for the assessment of tissue blood flow, but increased reproducibility would facilitate longitudinal studies. The aim of the study was to assess the interday reproducibility of Laser Doppler Flowmetry (LDF) at rest, at elevated local temperatures, and with the use of the vasodilator Methyl Nicotinate (MN) in six interconnected protocols for the measurement of the blood supply to the microvascular bed of the gingiva. METHODS Ten healthy volunteers were included. Interweek LDF measurements with custom-made acrylic splints were performed. Six protocols were applied in separate regions of interest (ROI): 1; basal LDF, 2; LDF with thermoprobe 42 °C, 3; LDF with thermoprobe 45 °C, 4; LDF with thermoprobe 42 °C and MN, 5; LDF with thermoprobe 45 °C and MN and 6; LDF with MN. RESULTS Intra-individual reproducibility was assessed by the within-subject coefficient of variation (wCV) and the intraclass correlation coefficient (ICC). Basal LDF measurements demonstrated high reproducibility with wCV 11.1 in 2 min and 10.3 in 5 min. ICC was 0.9 and 0.92. wCV after heat and MN was 4.9-10.3 and ICC 0.82-0.93. The topically applied MN yielded increased blood flow. CONCLUSION This is the first study evaluating the reproducibility of basal LDF compared to single or multiple vasodilatory stimuli in gingiva. Multiple collector fibers probe and stabilizing acrylic splints are recommended. Vasodilatory stimulation showed a tendency toward higher reproducibility. Furthermore, MN yields vasodilation in gingiva.
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Affiliation(s)
- Aida Ajan
- Department of Oral and Maxillofacial Surgery, Linköping University Hospital, Linköping, Sweden; Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden.
| | - Karin Roberg
- Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden; Department of Otorhinolaryngology in Linköping, Region Östergötland, Linköping, Sweden.
| | - Ingemar Fredriksson
- Department of Biomedical Engineering (IMT), Linköping University, Linköping, Sweden.
| | - Jahan Abtahi
- Department of Oral and Maxillofacial Surgery, Linköping University Hospital, Linköping, Sweden; Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden.
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Keeling NM, Wallisch M, Johnson J, Le HH, Vu HH, Jordan KR, Puy C, Tucker EI, Nguyen KP, McCarty OJT, Aslan JE, Hinds MT, Anderson DEJ. Pharmacologic targeting of coagulation factors XII and XI by monoclonal antibodies reduces thrombosis in nitinol stents under flow. J Thromb Haemost 2024; 22:1433-1446. [PMID: 38331196 PMCID: PMC11055672 DOI: 10.1016/j.jtha.2024.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 01/11/2024] [Accepted: 01/28/2024] [Indexed: 02/10/2024]
Abstract
BACKGROUND Cardiovascular implantable devices, such as vascular stents, are critical for the treatment of cardiovascular diseases. However, their success is dependent on robust and often long-term antithrombotic therapies. Yet, the current standard-of-care therapies often pose significant bleeding risks to patients. Coagulation factor (F)XI and FXII have emerged as potentially safe and efficacious targets to safely reduce pathologic thrombin generation in medical devices. OBJECTIVES To study the efficacy of monoclonal antibody-targeting FXII and FXI of the contact pathway in preventing vascular device-related thrombosis. METHODS The effects of inhibition of FXII and FXI using function-blocking monoclonal antibodies were examined in a nonhuman primate model of nitinol stent-related thrombosis under arterial and venous flow conditions. RESULTS We found that function-blocking antibodies of FXII and FXI reduced markers of stent-induced thrombosis in vitro and ex vivo. However, FXI inhibition resulted in more effective mitigation of thrombosis markers under varied flow conditions. CONCLUSION This work provides further support for the translation of contact pathway of coagulation inhibitors for their adjunctive clinical use with cardiovascular devices.
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Affiliation(s)
- Novella M Keeling
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado, USA.
| | - Michael Wallisch
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Aronora Inc, Portland, Oregon, USA
| | - Jennifer Johnson
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Hillary H Le
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Helen H Vu
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Kelley R Jordan
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Cristina Puy
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Erik I Tucker
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Aronora Inc, Portland, Oregon, USA
| | - Khanh P Nguyen
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Veterans Affairs Portland Health Care System, Portland, Oregon, USA
| | - Owen J T McCarty
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Division of Hematology & Medical Oncology, Oregon Health & Science University, Portland, Oregon, USA
| | - Joseph E Aslan
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA; Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Monica T Hinds
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA
| | - Deirdre E J Anderson
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon, USA.
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Hill EC, Proppe CE, Rivera PM, Lubiak SM, Gonzalez Rojas DH, Lawson JE, Choi H, Mansy H, Keller JL. Blood flow restriction attenuates surface mechanomyography lateral and longitudinal, but not transverse oscillations during fatiguing exercise. Physiol Meas 2024; 45:045002. [PMID: 38507792 DOI: 10.1088/1361-6579/ad360b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 03/20/2024] [Indexed: 03/22/2024]
Abstract
Objective. Surface mechanomyography (sMMG) can measure oscillations of the activated muscle fibers in three axes (i.e.X,Y, andZ-axes) and has been used to describe motor unit activation patterns (X-axis). The application of blood flow restriction (BFR) is common in exercise studies, but the cuff may restrict muscle fiber oscillations. Therefore, the purpose of this investigation was to examine the acute effects of submaximal, fatiguing exercise with and without BFR on sMMG amplitude in theX,Y, andZ-axes among female participants.Approach. Sixteen females (21 ± 1 years) performed two separate exercise bouts to volitional exhaustion that consisted of unilateral, submaximal (50% maximal voluntary isometric contraction [MVIC]) intermittent, isometric, leg extensions with and without BFR. sMMG was recorded and examined across percent time to exhaustion (%TTE) in 20% increments. Separate 2-way repeated measures ANOVA models were constructed: (condition [BFR, non-BFR]) × (time [20, 40, 60, 80, and 100% TTE]) to examine absolute (m·s-2) and normalized (% of pretest MVIC) sMMG amplitude in theX-(sMMG-X),Y-(sMMG-Y), andZ-(sMMG-Z) axes.Main results. The absolute sMMG-X amplitude responses were attenuated with the application of BFR (mean ± SD = 0.236 ± 0.138 m·s-2) relative to non-BFR (0.366 ± 0.199 m·s-2, collapsed across time) and for sMMG-Y amplitude at 60%-100% of TTE (BFR range = 0.213-0.232 m·s-2versus non-BFR = 0.313-0.445 m·s-2). Normalizing sMMG to pretest MVIC removed most, but not all the attenuation which was still evident for sMMG-Y amplitude at 100% of TTE between BFR (72.9 ± 47.2%) and non-BFR (98.9 ± 53.1%). Interestingly, sMMG-Z amplitude was not affected by the application of BFR and progressively decreased across %TTE (0.332 ± 0.167 m·s-2to 0.219 ± 0.104 m·s-2, collapsed across condition.)Significance. The application of BFR attenuated sMMG-X and sMMG-Y amplitude, although normalizing sMMG removed most of this attenuation. Unlike theXandY-axes, sMMG-Z amplitude was not affected by BFR and progressively decreased across each exercise bout potentially tracking the development of muscle fatigue.
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Affiliation(s)
- Ethan C Hill
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
- Florida Space Institute, Partnership I, Research Parkway, University of Central Florida, Orlando, FL 32826, United States of America
- College of Medicine, 6850 Lake Nona Blvd, University of Central Florida, Orlando, FL 32827, United States of America
| | - Chris E Proppe
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
| | - Paola M Rivera
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
| | - Sean M Lubiak
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
| | - David H Gonzalez Rojas
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
| | - John E Lawson
- School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America
| | - Hwan Choi
- College of Engineering, Mechanical and Aerospace, 4328 Scorpius St, University of Central Florida, Orlando, FL 32816, United States of America
| | - Hansen Mansy
- College of Engineering, Mechanical and Aerospace, 4328 Scorpius St, University of Central Florida, Orlando, FL 32816, United States of America
| | - Joshua L Keller
- College of Education and Professional Studies, University of South Alabama, Mobile, AL 36618, United States of America
- College of Medicine, Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL 36618, United States of America
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Wong BJ, Turner CG, Hayat MJ, Otis JS, Quyyumi AA. Inhibition of superoxide and iNOS augment cutaneous nitric oxide-dependent vasodilation in non-Hispanic black young adults. Physiol Rep 2024; 12:e16021. [PMID: 38639714 PMCID: PMC11027894 DOI: 10.14814/phy2.16021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 04/04/2024] [Indexed: 04/20/2024] Open
Abstract
We assessed the combined effect of superoxide and iNOS inhibition on microvascular function in non-Hispanic Black and non-Hispanic White participants (n = 15 per group). Participants were instrumented with four microdialysis fibers: (1) lactated Ringer's (control), (2) 10 μM tempol (superoxide inhibition), (3) 0.1 mM 1400 W (iNOS inhibition), (4) tempol + 1400 W. Cutaneous vasodilation was induced via local heating and NO-dependent vasodilation was quantified. At control sites, NO-dependent vasodilation was lower in non-Hispanic Black (45 ± 9% NO) relative to non-Hispanic White (79 ± 9% NO; p < 0.01; effect size, d = 3.78) participants. Tempol (62 ± 16% NO), 1400 W (78 ± 12% NO) and tempol +1400 W (80 ± 13% NO) increased NO-dependent vasodilation in non-Hispanic Black participants relative to control sites (all p < 0.01; d = 1.22, 3.05, 3.03, respectively). The effect of 1400 W (p = 0.04, d = 1.11) and tempol +1400 W (p = 0.03, d = 1.22) was greater than tempol in non-Hispanic Black participants. There was no difference between non-Hispanic Black and non-Hispanic White participants at 1400 W or tempol + 1400 W sites. These data suggest iNOS has a greater effect on NO-dependent vasodilation than superoxide in non-Hispanic Black participants.
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Affiliation(s)
- Brett J. Wong
- Department of Kinesiology & HealthGeorgia State UniversityAtlantaGeorgiaUSA
| | - Casey G. Turner
- Department of Kinesiology & HealthGeorgia State UniversityAtlantaGeorgiaUSA
- Molecular Cardiology Research InstituteTufts Medical CenterBostonMassachusettsUSA
| | - Matthew J. Hayat
- Department of Population Health Sciences, School of Public HealthGeorgia State UniversityAtlantaGeorgiaUSA
| | - Jeffrey S. Otis
- Department of Kinesiology & HealthGeorgia State UniversityAtlantaGeorgiaUSA
| | - Arshed A. Quyyumi
- Emory Clinical Cardiology Research InstituteEmory University School of MedicineAtlantaGeorgiaUSA
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Trbovich M, Wu Y, Romo T, Koek W, Kellogg D. Mechanistic involvement of noradrenergic neuronal neurotransmitter release in cutaneous vasoconstriction during autonomic dysreflexia in persons with spinal cord injury. Auton Neurosci 2024; 252:103154. [PMID: 38330594 DOI: 10.1016/j.autneu.2024.103154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/22/2023] [Accepted: 01/24/2024] [Indexed: 02/10/2024]
Abstract
INTRODUCTION Autonomic dysreflexia (AD) is a potentially life-threatening consequence in high (above T6) spinal cord injury that involves multiple incompletely understood mechanisms. While peripheral arteriolar vasoconstriction, which controls systemic vascular resistance, is documented to be pronounced during AD, the pathophysiological neurovascular junction mechanisms of this vasoconstriction are undefined. One hypothesized mechanism is increased neuronal release of norepinephrine and co-transmitters. We tested this by examining the effects of blockade of pre-synaptic neural release of norepinephrine and co-transmitters on cutaneous vasoconstriction during AD, using a novel non-invasive technique; bretylium (BT) iontophoresis followed by skin blood flow measurements via laser doppler flowmetry (LDF). METHODS Bretylium, a sympathetic neuronal blocking agent (blocks release of norepinephrine and co-transmitters) was applied iontophoretically to the skin of a sensate (arm) and insensate (leg) area in 8 males with motor complete tetraplegia. An nearby untreated site served as control (CON). Cutaneous vascular conductance (CVC) was measured (CVC = LDF/mean arterial pressure) at normotension before AD was elicited by bladder stimulation. The percent drop in CVC values from pre-AD vs. AD was compared among BT and CON sites in sensate and insensate areas. RESULTS There was a significant effect of treatment but no significant effect of limb/sensation or interaction of limb x treatment on CVC. The percent drop in CVC between BT and CON treated sites was 25.7±1.75 vs. 39.4±0.87, respectively (P = 0.004). CONCLUSION Bretylium attenuates, but does not fully abolish vasoconstriction during AD. This suggests release of norepinephrine and cotransmitters from cutaneous sympathetic nerves is involved in cutaneous vasoconstriction during AD.
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Affiliation(s)
- Michelle Trbovich
- Department of Rehabilitation Medicine, University of Texas Health Science Center, San Antonio Audie L. Murphy Memorial Veterans Affairs Hospital, San Antonio, TX, United States of America; South Texas Veteran's Health Care System, San Antonio, TX, United States of America.
| | - Yubo Wu
- South Texas Veteran's Health Care System, San Antonio, TX, United States of America
| | - Terry Romo
- Department of Rehabilitation Medicine, University of Texas Health Science Center, San Antonio Audie L. Murphy Memorial Veterans Affairs Hospital, San Antonio, TX, United States of America; South Texas Veteran's Health Care System, San Antonio, TX, United States of America
| | - Wouker Koek
- Department of Cell Systems and Anatomy, University of Texas Health Science Center, San Antonio, United States of America
| | - Dean Kellogg
- Department of Medicine, University of TX Health Science Center, San Antonio, United States of America; Geriatric Research Education and Clinical Center and Dept of Medicine, University of Texas Health Science Center, San Antonio, United States of America; South Texas Veteran's Health Care System, San Antonio, TX, United States of America
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Mellinger A, Hersant J, Bourreau C, Lecoq S, Deveze E, Clere N, Henni S. Caliper, contrast enhanced-ultrasound or laser speckle contrast imaging: Techniques to follow mice melanoma growth. J Biophotonics 2024; 17:e202300439. [PMID: 38302735 DOI: 10.1002/jbio.202300439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 02/03/2024]
Abstract
Due to morphological characteristics, metastatic melanoma is a cancer for which vascularization is not a diagnostic criterion. Laser speckle contrast imaging (LSCI) and contrast enhanced ultrasound (CEUS) are two imaging techniques that will be explored in this study, which aims to confirm these two techniques for monitoring tumor vascularization. B16F10 cells were xenografted to C57BL/6 mice treated with anti-PD1 or 0.9% NaCl. Tumor volume was measured daily while CEUS and LSCI were performed weekly. LSCI and CEUS analyses showed a decrease in tumor perfusion in both groups of mice. Although both CEUS and LSCI are useful for measuring tumor volume, LSCI appears to be more robust and effective for monitoring tumor microcirculation. Non-invasive investigations are needed to better predict tumor vascularization: CEUS and LSCI have a good applicability in a mice model.
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Affiliation(s)
| | | | - Clara Bourreau
- Univ Angers, Inserm, CNRS, MINT, SFR ICAT, Angers, France
| | - Simon Lecoq
- Vascular Medicine, University Hospital, Angers, France
| | - Eva Deveze
- Vascular Surgery, University Hospital, Angers, France
| | - Nicolas Clere
- Univ Angers, Inserm, CNRS, MINT, SFR ICAT, Angers, France
| | - Samir Henni
- Vascular Medicine, University Hospital, Angers, France
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Dubensky A, Ryzhkov I, Tsokolaeva Z, Lapin K, Kalabushev S, Varnakova L, Dolgikh V. Post-occlusive reactive hyperemia variables can be used to diagnose vascular dysfunction in hemorrhagic shock. Microvasc Res 2024; 152:104647. [PMID: 38092223 DOI: 10.1016/j.mvr.2023.104647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/24/2023] [Accepted: 12/08/2023] [Indexed: 02/03/2024]
Abstract
INTRODUCTION Laser doppler flowmetry (LDF) allows non-invasive assessment of microvascular functions. The combination of LDF with an occlusion functional test enables study of post-occlusive reactive hyperemia (PORH), providing additional information about vasomotor function, capillary blood flow reserve, and the overall reactivity of the microvascular system. AIM To identify early alterations of PORH variables in the skin of a rat in hemorrhagic shock (HS). MATERIAL AND METHODS Male Wistar rats (n = 14) weighing 400-450 g were anesthetized with a combination of tiletamine/zolazepam (20 mg/kg) and xylazine (5 mg/kg). The animals breathed on their own, and were placed on a heated platform in the supine position. A PE-50 catheter was inserted into the carotid artery to measure the mean arterial pressure (MAP). The optical probe of the Laser Doppler device was installed on the plantar surface of the hind limb of a rat; a pneumatic cuff was applied proximal to the same limb. The occlusion time was 3 min. The following physiological variables were measured at baseline and 30 min after blood loss: MAP, mmHg; mean cutaneous blood flow (M, PU); cutaneous vascular conductance (CVC = M/MAP); peak hyperemia (Mmax, PU) and maximum cutaneous vascular conductance (CVCmax) during PORH. In the HS group (n = 7), 30 % of the estimated blood volume was taken within 5 min. There was no blood loss in the group of sham-operated animals (Sham, n = 7). The results are presented as Me [25 %;75 %]. The U-Mann-Whitney criterion was used to evaluate intergroup differences. Differences were considered statistically significant at p < 0.05. RESULTS The groups did not differ at baseline. Blood loss led to a significant decrease in MAP (43 [31;46] vs. 94 [84;104] mmHg), M (11.5 [16.9;7.8] vs 16.7 [20.2;13.9]) and Mmax (18.1 [16.4;21.8] vs. 25.0 [23.0;26.2]) in the HS group compared to the Sham group, respectively. At the same time, both CVC (0.25 [0.23;0.30] vs. 0.16 [0.14;0.21]) and CVCmax (0.55 [0.38;0.49] vs 0.24 [0.23; 0.29]) increased after blood loss in the HS group compared to the Sham group. Arterial blood gas analysis revealed metabolic lactic acidosis in the HS group. CONCLUSION In this rat model of HS, alterations in cutaneous blood flow are manifested by a decrease in perfusion (M) and the intensity of PORH (Mmax) with a simultaneous increase in vascular conductance (CVC and CVCmax).
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Affiliation(s)
- Aleksey Dubensky
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | - Ivan Ryzhkov
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Zoya Tsokolaeva
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | - Konstantin Lapin
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Sergey Kalabushev
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Lidia Varnakova
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Vladimir Dolgikh
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
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Wu CK, Lin CH. Integrating vascular access surveillance with clinical monitoring for stenosis prediction. J Nephrol 2024; 37:461-470. [PMID: 37980698 DOI: 10.1007/s40620-023-01799-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 09/27/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND Arteriovenous fistula and arteriovenous graft are the most common types of vascular access for dialysis; stenosis and thrombosis are major complications leading to access failure and to an incresed risk of mortality. The aim of the present study was to assess the results of integrating strict vascular access blood flow surveillance with routine clinical monitoring for predicting vascular access stenosis in chronic hemodialysis patients. METHODS In this retrospective study, chronic dialysis patients with arteriovenous fistula or arteriovenous graft were included from a setting in which all patients underwent quarterly blood flow surveillance in 2017. The results of blood flow surveillance were confirmed by thorough physical examination. Predictive performance of blood flow surveillance models in detecting stenosis in patients with arteriovenous fistula or arteriovenous graft was evaluated. The predictive performance of the quarterly blood flow surveillance model was described by confusion matrix. Differences in accuracy, positive predictive value (PPV), and negative predictive value (NPV) between blood flow surveillance models with distinct blood flow thresholds were evaluated. RESULTS Of 397 included patients, 336 had an arteriovenous fistula and 61 had an arteriovenous graft. In 2017, 106 percutaneous transluminal angioplasty procedures were performed in patients with an arteriovenous fistula, and 63 in patients with an arteriovenous graft. The results revealed similar predictive performance of surveillance models using an absolute blood flow threshold of < 500 or < 400 mL/min in predicting stenosis in patients with arteriovenous fistula. Blood flow surveillance models for patients with an arteriovenous fistula had significantly higher accuracy than those for patients with an arteriovenous graft. Furthermore, the use of a relative threshold, defined as blood flow < 1000 mL/min and a 25% decline in blood flow, did not affect the predictive performance of blood flow surveillance models. CONCLUSION Blood flow surveillance models using thresholds of < 400 and < 600 mL/min, followed by thorough physical examination, showed an accuracy of 91.54% and 72.15% in predicting stenosis in patients with arteriovenous fistula and arteriovenous graft, respectively. These two blood flow surveillance models may be integrated with routine clinical monitoring to improve early detection and treatment of stenosis in hemodialysis patients.
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Affiliation(s)
- Chung-Kuan Wu
- Division of Nephrology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
- School of Medicine, Fu-Jen Catholic University, New Taipei, Taipei, Taiwan
| | - Chia-Hsun Lin
- School of Medicine, Fu-Jen Catholic University, New Taipei, Taipei, Taiwan.
- Division of Cardiovascular Surgery, Department of Surgery, Shin Kong Wu Ho-Su Memorial Hospital, No. 95, Wenchang Rd., Shilin Dist., Taipei, 111045, Taiwan.
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10
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Sakamoto R, Kamoda T, Sato K, Ogoh S, Katayose M, Neki T, Iwamoto E. Acute aerobic exercise enhances cerebrovascular shear-mediated dilation in young adults: the role of cerebral shear. J Appl Physiol (1985) 2024; 136:535-548. [PMID: 38153849 DOI: 10.1152/japplphysiol.00543.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/22/2023] [Accepted: 12/22/2023] [Indexed: 12/30/2023] Open
Abstract
Exercise-induced increases in shear rate (SR) acutely improve peripheral endothelial function, but the presence of this mechanism in cerebral arteries remains unclear. Thus, we evaluated shear-mediated dilation of the internal carotid artery (ICA), which is an index of cerebrovascular endothelial function, before and after exercise. Shear-mediated dilation was measured with 30 s of hypercapnia in 16 young adults before and 10 min after 30 min of sitting rest (CON) or three cycling exercises on four separate days. The target exercise intensity was 80% of oxygen uptake at the ventilatory threshold. To manipulate the ICA SR during exercise, participants breathed spontaneously (ExSB, SR increase) or hyperventilated without (ExHV, no increase in SR) or with ([Formula: see text], restoration of SR increase) addition of CO2 to inspiratory air. Shear-mediated dilation was calculated as a percent increase in diameter from baseline. Doppler ultrasound measures ICA velocity and diameter. The CON trial revealed that 30 min of sitting did not alter shear-mediated dilation (4.34 ± 1.37% to 3.44 ± 1.23%, P = 0.052). ICA dilation after exercise compared with preexercise levels increased in the ExSB trial (3.32 ± 1.37% to 4.74 ± 1.84%, P < 0.01), remained unchanged in the ExHV trial (4.07 ± 1.55% to 3.21 ± 1.48%, P = 0.07), but was elevated in the [Formula: see text] trial (3.35 ± 1.15% to 4.33 ± 2.12%, P = 0.04). Our results indicate that exercise-induced increases in cerebral shear may play a crucial role in improving cerebrovascular endothelial function after acute exercise in young adults.NEW & NOTEWORTHY We found that 30-min cycling (target intensity was 80% of the ventilatory threshold) with increasing shear of the internal carotid artery (ICA) enhanced transient hypercapnia-induced shear-mediated dilation of the ICA, reflecting improved cerebrovascular endothelial function. This enhancement of ICA dilation was diminished by suppressing the exercise-induced increase in ICA shear via hyperventilation. Our results indicate that increases in cerebral shear may be a key stimulus for improving cerebrovascular endothelial function after exercise in young adults.
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Affiliation(s)
- Rintaro Sakamoto
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Tatsuki Kamoda
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Kohei Sato
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan
| | - Masaki Katayose
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Toru Neki
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Erika Iwamoto
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
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11
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Mautuit T, Cunnac P, Truffer F, Anjos A, Dufrane R, Maître G, Geiser M, Chiquet C. Absolute retinal blood flow in healthy eyes and in eyes with retinal vein occlusion. Microvasc Res 2024; 152:104648. [PMID: 38123065 DOI: 10.1016/j.mvr.2023.104648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 11/30/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023]
Abstract
PURPOSE To measure non-invasively retinal venous blood flow (RBF) in healthy subjects and patients with retinal venous occlusion (RVO). METHODS The prototype named AO-LDV (Adaptive Optics Laser Doppler Velocimeter), which combines a new absolute laser Doppler velocimeter with an adaptive optics fundus camera (rtx1, Imagine Eyes®, Orsay, France), was studied for the measurement of absolute RBF as a function of retinal vessel diameters and simultaneous measurement of red blood cell velocity. RBF was measured in healthy subjects (n = 15) and patients with retinal venous occlusion (RVO, n = 6). We also evaluated two softwares for the measurement of retinal vessel diameters: software 1 (automatic vessel detection, profile analysis) and software 2 (based on the use of deep neural networks for semantic segmentation of vessels, using a M2u-Net architecture). RESULTS Software 2 provided a higher rate of automatic retinal vessel measurement (99.5 % of 12,320 AO images) than software 1 (64.9 %) and wider measurements (75.5 ± 15.7 μm vs 70.9 ± 19.8 μm, p < 0.001). For healthy subjects (n = 15), all the retinal veins in one eye were measured to obtain the total RBF. In healthy subjects, the total RBF was 37.8 ± 6.8 μl/min. There was a significant linear correlation between retinal vessel diameter and maximal velocity (slope = 0.1016; p < 0.001; r2 = 0.8597) and a significant power curve correlation between retinal vessel diameter and blood flow (3.63 × 10-5 × D2.54; p < 0.001; r2 = 0.7287). No significant relationship was found between total RBF and systolic and diastolic blood pressure, ocular perfusion pressure, heart rate, or hematocrit. For RVO patients (n = 6), a significant decrease in RBF was noted in occluded veins (3.51 ± 2.25 μl/min) compared with the contralateral healthy eye (11.07 ± 4.53 μl/min). For occluded vessels, the slope between diameter and velocity was 0.0195 (p < 0.001; r2 = 0.6068) and the relation between diameter and flow was Q = 9.91 × 10-6 × D2.41 (p < 0.01; r2 = 0.2526). CONCLUSION This AO-LDV prototype offers new opportunity to study RBF in humans and to evaluate treatment in retinal vein diseases.
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Affiliation(s)
- Thibaud Mautuit
- Department of Ophthalmology, University Hospital of Grenoble-Alpes, France; Grenoble-Alpes University, HP2 Laboratory, INSERM U1042, Grenoble, France
| | - Pierre Cunnac
- Department of Ophthalmology, University Hospital of Grenoble-Alpes, France; Grenoble-Alpes University, HP2 Laboratory, INSERM U1042, Grenoble, France
| | | | - André Anjos
- Idiap Research Institute, Martigny, Switzerland
| | - Rebecca Dufrane
- Department of Ophthalmology, University Hospital of Grenoble-Alpes, France; Grenoble-Alpes University, HP2 Laboratory, INSERM U1042, Grenoble, France
| | | | | | - Christophe Chiquet
- Department of Ophthalmology, University Hospital of Grenoble-Alpes, France; Grenoble-Alpes University, HP2 Laboratory, INSERM U1042, Grenoble, France.
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12
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Spitz RW, Yamada Y, Wong V, Kataoka R, Hammert WB, Song JS, Kang A, Seffrin A, Loenneke JP. Blood flow restriction pressure for narrow cuffs (5 cm) cannot be estimated with precision. Physiol Meas 2024; 45:02NT01. [PMID: 38330491 DOI: 10.1088/1361-6579/ad278d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 02/08/2024] [Indexed: 02/10/2024]
Abstract
Blood flow restriction pressures are set relative to the lowest pressure needed to occlude blood flow with that specific cuff. Due to pressure limitations of some devices, it is often not possible to occlude blood flow in all subjects and apply a known relative pressure in the lower body with a 5 cm wide cuff.Objective. To use a device capable of generating high pressures (up to 907 mmHg) to create and validate an estimation equation for the 5 cm cuff in the lower body using a 12 cm cuff.Approach. 170 participants had their arterial occlusion pressure (AOP) with a 5 cm and 12 cm cuff and their thigh circumference measured in their right leg. The sample was randomly allocated to a prediction group (66%) and validation group (33%). Thigh circumference and 12 cm AOP were used as predictors. A Bland-Altman plot was constructed to assess agreement between measured and predicted values.Main results. The mean difference (95% confidence interval) between the observed (336.8 mmHg) and the predicted (343.9 mmHg) 5 cm AOP was 7.1 (-11.9, 26.1) mmHg. The 95% limits of agreement were -133.6 to 147.8 mmHg. There was a negative relationship between the difference and the average of predicted and measured 5 cm AOP (B= -0.317,p= 0.000043).Significance. Although this was the first study to quantify AOP over 600 mmHg with a 5 cm cuff, our equation is not valid across all levels of pressure. If possible, larger cuff widths should be employed in the lower body.
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Affiliation(s)
- Robert W Spitz
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, United States of America
| | - Yujiro Yamada
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - Vickie Wong
- Department of Sport and Health, Solent University, Southampton, Hampshire SO14 0YN, United Kingdom
| | - Ryo Kataoka
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - William B Hammert
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - Jun Seob Song
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - Anna Kang
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - Aldo Seffrin
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
| | - Jeremy P Loenneke
- Department of Health, Exercise Science, and Recreation Management. Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, MS, United States of America
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13
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Wang Q, Wang Q, Ning Z, Chan KF, Jiang J, Wang Y, Su L, Jiang S, Wang B, Ip BYM, Ko H, Leung TWH, Chiu PWY, Yu SCH, Zhang L. Tracking and navigation of a microswarm under laser speckle contrast imaging for targeted delivery. Sci Robot 2024; 9:eadh1978. [PMID: 38381838 DOI: 10.1126/scirobotics.adh1978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 01/26/2024] [Indexed: 02/23/2024]
Abstract
Micro/nanorobotic swarms consisting of numerous tiny building blocks show great potential in biomedical applications because of their collective active delivery ability, enhanced imaging contrast, and environment-adaptive capability. However, in vivo real-time imaging and tracking of micro/nanorobotic swarms remain a challenge, considering the limited imaging size and spatial-temporal resolution of current imaging modalities. Here, we propose a strategy that enables real-time tracking and navigation of a microswarm in stagnant and flowing blood environments by using laser speckle contrast imaging (LSCI), featuring full-field imaging, high temporal-spatial resolution, and noninvasiveness. The change in dynamic convection induced by the microswarm can be quantitatively investigated by analyzing the perfusion unit (PU) distribution, offering an alternative approach to investigate the swarm behavior and its interaction with various blood environments. Both the microswarm and surrounding environment were monitored and imaged by LSCI in real time, and the images were further analyzed for simultaneous swarm tracking and navigation in the complex vascular system. Moreover, our strategy realized real-time tracking and delivery of a microswarm in vivo, showing promising potential for LSCI-guided active delivery of microswarm in the vascular system.
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Affiliation(s)
- Qinglong Wang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Qianqian Wang
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing, China
| | - Zhipeng Ning
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Kai Fung Chan
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
| | - Jialin Jiang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Yuqiong Wang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Lin Su
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Shuai Jiang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Ben Wang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, China
| | - Bonaventure Yiu Ming Ip
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Ho Ko
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Thomas Wai Hong Leung
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Philip Wai Yan Chiu
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
- Department of Surgery, CUHK, Shatin, N.T., Hong Kong, China
| | - Simon Chun Ho Yu
- Department of Imaging and Interventional Radiology, CUHK, Shatin, N.T., Hong Kong, China
| | - Li Zhang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
- Department of Surgery, CUHK, Shatin, N.T., Hong Kong, China
- CUHK T Stone Robotics Institute, CUHK, Shatin, N.T., Hong Kong, China
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14
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Pauly S, Mo P, Elliott J, Bleakney A, Pappu S, Jan Y. Effects of alternating pressure patterns on sacral skin blood flow responses in people with spinal cord injury. Int Wound J 2024; 21:e14792. [PMID: 38356253 PMCID: PMC10867481 DOI: 10.1111/iwj.14792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 02/02/2024] [Indexed: 02/16/2024] Open
Abstract
Alternating pressure support surface (APSS) is a common support surface for treating pressure injury in individuals with spinal cord injury (SCI). However, conflicting results on the effectiveness of APSS have been reported and may be associated with inappropriate configurations of APSS. The objectives of this study were to compare the different pressure amplitudes (75/5 mmHg [alternating between 75 and 5 mmHg] vs. 65/15 mmHg) and cycle periods (5 min [4 cycles] vs. 2.5 min [8 cycles]) of alternating pressure on sacral skin blood flow responses in 10 individuals with SCI. Sacral skin blood flow during and after loading of four alternating pressure protocols was assessed using laser Doppler flowmetry and was normalised to the value before loading (10-min baseline, 20-min loading and 10-min recovery). The results demonstrated that during the high-pressure phase, there was a significant difference between the 75/5 and 65/15 mmHg protocols (0.3658 ± 0.0688 for 75/5 mmHg and 0.1702 ± 0.0389 for 65/15 mmHg, p < 0.05); and during the low-pressure phase, there was a significant difference between the 75/5 and 65/15 mmHg protocols (1.7184 ± 0.262 for 75/5 mmHg and 0.5916 ± 0.1378 for 65/15 mmHg, p < 0.05). There were no differences between cycle periods in skin blood flow responses. No adverse events were reported. Our finding indicates that the pressure amplitude of alternating pressure is a significant factor affecting sacral skin blood flow responses. An appropriate configuration of alternating pressure is needed to effectively increase skin blood flow and tissue viability in individuals with SCI.
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Affiliation(s)
- Serah Pauly
- Department of Kinesiology and Community HealthUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| | - Pu‐Chun Mo
- Department of Kinesiology and Community HealthUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| | - Jeannette Elliott
- Disability Resources and Educational ServicesUniversity of Illinois at Urbana‐ChampaignChampaignIllinoisUSA
| | - Adam Bleakney
- Disability Resources and Educational ServicesUniversity of Illinois at Urbana‐ChampaignChampaignIllinoisUSA
| | - Suguna Pappu
- Department of NeurosurgeryCarle Foundation HospitalUrbanaIllinoisUSA
| | - Yih‐Kuen Jan
- Department of Kinesiology and Community HealthUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
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15
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Rein‐Hedin E, Sjöberg F, Ganslandt C, Skoog J, Zachrisson H, Bengtsson T, Dalsgaard C. Utilizing venous occlusion plethysmography to assess vascular effects: A study with buloxibutid, an angiotensin II type 2 receptor agonist. Clin Transl Sci 2024; 17:e13735. [PMID: 38344891 PMCID: PMC10859786 DOI: 10.1111/cts.13735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/22/2023] [Accepted: 01/21/2024] [Indexed: 02/15/2024] Open
Abstract
Buloxibutid (also known as C21) is a potent and selective angiotensin II type 2 receptor (AT2R) agonist, in development for oral treatment of fibrotic lung disease. This phase I, open-label, pharmacodynamic study investigated vascular effects of buloxibutid in five healthy male volunteers. Subjects were administered intra-arterial infusions of buloxibutid for 5 min in ascending doses of 3, 10, 30, 100, and 200 μg/min, infused sequentially in the forearm. Infusions of sodium nitroprusside (SNP) solution in doses of 0.8-3.2 μg/min were administered as a positive control. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Safety and tolerability of intra-arterial administrations of buloxibutid were evaluated. Following infusion of buloxibutid in doses of 3-200 μg/min, the range of increase in FBF was 27.8%, 17.2%, 37.0%, 28.5%, and 60.5%, compared to the respective baseline. The largest increase was observed in the highest dose group. Infusions of SNP as a positive control, increased FBF 230-320% compared to baseline. Three adverse events (AEs) of mild intensity, not related to buloxibutid or SNP, were reported for two subjects. Two of these AEs were related to study procedures. There were no clinically relevant changes in arterial blood pressure during the study period. Intra-arterial infusion of buloxibutid in low, ascending doses increased FBF, indicating that buloxibutid may be effective in conditions associated with endothelial dysfunction. Venous occlusion plethysmography was found to be a useful method to explore pharmacodynamic vascular effects of novel AT2R agonists, while avoiding systemic adverse effects.
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Affiliation(s)
- Erik Rein‐Hedin
- CTC Clinical Trial Consultants ABUppsalaSweden
- Department of Surgical Sciences, Plastic SurgeryUppsala UniversityUppsalaSweden
| | - Folke Sjöberg
- CTC Clinical Trial Consultants ABUppsalaSweden
- Department of Biomedical and Clinical SciencesLinköping UniversityLinköpingSweden
| | | | - Johan Skoog
- Department of Clinical Physiology and Department of Health, Medicine and Caring SciencesLinköping UniversityLinköpingSweden
| | - Helene Zachrisson
- Department of Clinical Physiology and Department of Health, Medicine and Caring SciencesLinköping UniversityLinköpingSweden
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16
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Draghici AE, Ely MR, Hamner JW, Taylor JA. Nitric oxide-mediated vasodilation in human bone. Microcirculation 2024; 31:e12842. [PMID: 38133925 PMCID: PMC10922487 DOI: 10.1111/micc.12842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 11/20/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023]
Abstract
OBJECTIVE Regulation of blood flow to bone is critical but poorly understood, particularly in humans. This study aims to determine whether nitric oxide (NO), a major regulator of vascular tone to other tissues, contributes also to the regulation of blood flow to bone. METHODS In young healthy adults (n = 16, 8F, 8M), we characterized NO-mediated vasodilation in the tibia in response to sublingual nitroglycerin and contrasted it to lower leg. Blood flow responses were assessed in supine individuals by continuously measuring tibial total hemoglobin (tHb) via near-infrared spectroscopy and lower leg blood flow (LBF) as popliteal flow velocity via Doppler ultrasound in the same leg. RESULTS LBF increased by Δ9.73 ± 0.66 cm/s and peaked 4.4 min after NO administration and declined slowly but remained elevated (Δ3.63 ± 0.60 cm/s) at 10 min. In contrast, time to peak response was longer and smaller in magnitude in the tibia as tHb increased Δ2.08 ± 0.22 μM and peaked 5.3 min after NO administration and declined quickly but remained elevated (Δ0.87±0.22 μM) at 10 min (p = .01). CONCLUSIONS In young adults, the tibial vasculature demonstrates robust NO-mediated vasodilation, but tHb is delayed and diminishes faster compared to LBF, predominately reflective of skeletal muscle responses. Thus, NO-mediated vasodilation in bone may be characteristically different from other vascular beds.
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Affiliation(s)
- Adina E. Draghici
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA
- Cardiovascular Research Laboratory, Spaulding Hospital Cambridge, Cambridge, MA
- Schoen Adams Research Institute at Spaulding Rehabilitation, Boston, MA
| | - Matthew R. Ely
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA
- Cardiovascular Research Laboratory, Spaulding Hospital Cambridge, Cambridge, MA
- Schoen Adams Research Institute at Spaulding Rehabilitation, Boston, MA
| | - Jason W. Hamner
- Cardiovascular Research Laboratory, Spaulding Hospital Cambridge, Cambridge, MA
- Schoen Adams Research Institute at Spaulding Rehabilitation, Boston, MA
| | - J. Andrew Taylor
- Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA
- Cardiovascular Research Laboratory, Spaulding Hospital Cambridge, Cambridge, MA
- Schoen Adams Research Institute at Spaulding Rehabilitation, Boston, MA
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17
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Zhao L, Liu S, Liu Y, Tang H. Vasomotion heterogeneity and spectral characteristics in diabetic and hypertensive patients. Microvasc Res 2024; 151:104620. [PMID: 37923118 DOI: 10.1016/j.mvr.2023.104620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/13/2023] [Accepted: 10/28/2023] [Indexed: 11/07/2023]
Abstract
Vasomotion refers to the spontaneous oscillation of blood vessels within a frequency range of 0.01 to 1.6 Hz. Various disease states, including hypertension and diabetes, have been associated with alterations in vasomotion at the finger, indicating potential impairment of skin microcirculation. Due to the non-linear nature of human vasculature, the modification of vasomotion may vary across different locations for different diseases. In this study, Laser Doppler Flowmetry was used to measure blood flow motion at acupoints LU8, LU5, SP6, and PC3 among 49 participants with or without diabetes and/or hypertension. Fast Fourier Transformation was used to analyze noise type while Hilbert-Huang Transformation and wavelet analysis were applied to assess Signal Noise Ratio (SNR) results. Statistical analysis revealed that different acupoints exhibit distinct spectral characteristics of vasomotion not only among healthy individuals but also among patients with diabetes and/or hypertension. The results showed strong heterogeneity of vasomotion among blood vessels, indicating that the vasomotion measured at a certain point may not reflect the real status of microcirculation.
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Affiliation(s)
- Liangjing Zhao
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Shuhong Liu
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Yang Liu
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Hui Tang
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
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Richey RE, Ruiz YI, Cope HL, Moore AM, Walsh MA, Garfield TC, Olivencia-Yurvati AH, Romero SA. Cyclooxygenase inhibition does not blunt thermal hyperemia in skeletal muscle of humans. J Appl Physiol (1985) 2024; 136:151-157. [PMID: 38059292 DOI: 10.1152/japplphysiol.00657.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023] Open
Abstract
Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. The cyclooxygenase pathway is active in skeletal muscle, is heat sensitive, and contributes to cutaneous thermal hyperemia in young healthy humans. Therefore, the purpose of this study was to test the hypothesis that cyclooxygenase inhibition would attenuate blood flow in the vastus lateralis muscle during localized heating. Twelve participants (6 women) were studied on two separate occasions: 1) time control (i.e., no ibuprofen); and 2) ingestion of 800 mg ibuprofen, a nonselective cyclooxygenase inhibitor. Experiments were randomized, counter-balanced, and separated by at least 10 days. Pulsed short-wave diathermy was used to induce unilateral deep heating of the vastus lateralis for 90 min, whereas the contralateral leg served as a thermoneutral control. Microdialysis was utilized to bypass the cutaneous circulation and directly measure local blood flow in the vastus lateralis muscle of each leg via the ethanol washout technique. Heat exposure increased muscle temperature and local blood flow (both P < 0.01 vs. baseline). However, the thermal hyperemic response did not differ between control and ibuprofen conditions (P ≥ 0.2). Muscle temperature slightly decreased for the thermoneutral leg (P < 0.01 vs. baseline), yet local blood flow remained relatively unchanged across time for control and ibuprofen conditions (both P ≥ 0.7). Taken together, our data suggest that inhibition of cyclooxygenase-derived vasodilator prostanoids does not blunt thermal hyperemia in skeletal muscle of young healthy humans.NEW & NOTEWORTHY Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. Using a pharmacological approach combined with microdialysis, we found that thermal hyperemia in the vastus lateralis muscle was well maintained despite the successful inhibition of cyclooxygenase. Our results suggest that cyclooxygenase-derived vasodilator prostanoids do not contribute to thermal hyperemia in skeletal muscle of young healthy humans.
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Affiliation(s)
- Rauchelle E Richey
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Ysabella I Ruiz
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Heidi L Cope
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Amy M Moore
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Mackenzie A Walsh
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Tyson C Garfield
- Department of Internal Medicine and Geriatrics, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Albert H Olivencia-Yurvati
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
- Department of Surgery, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Steven A Romero
- Department of Physiology and Anatomy, Human Vascular Physiology Laboratory, University of North Texas Health Science Center, Fort Worth, Texas, United States
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Ratchford SM, Broxterman RM, La Salle DT, Kwon OS, Hopkins PN, Richardson RS, Trinity JD. Obesity does not alter vascular function and handgrip exercise hemodynamics in middle-aged patients with hypertension. Am J Physiol Regul Integr Comp Physiol 2024; 326:R1-R9. [PMID: 37842741 DOI: 10.1152/ajpregu.00105.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/19/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023]
Abstract
Lifestyle modification including exercise training is often the first line of defense in the treatment of obesity and hypertension (HTN), however, little is known regarding how these potentially compounding disease states impact vasodilatory and hemodynamic responses at baseline and exercise. Therefore, this study sought to compare the impact of obesity on vascular function and hemodynamics at baseline and during handgrip (HG) exercise among individuals with HTN. Non-obese (13M/7F, 56 ± 16 yr, 25 ± 4 kg/m2) and obese (17M/4F, 50 ± 7 yr, 35 ± 4 kg/m2) middle-aged individuals with HTN forwent antihypertensive medication use for ≥2 wk before assessment of vascular function by brachial artery flow-mediated dilation (FMD) and exercise hemodynamics during progressive HG exercise at 15-30-45% maximal voluntary contraction (MVC). FMD was not different between Non-Obese (4.1 ± 1.7%) and Obese (5.2 ± 1.9%, P = 0.11). Systolic blood pressure (SBP) was elevated by ∼15% during the supine baseline and during HG exercise in the obese group. The blood flow response to HG exercise at 30% and 45% MVC was ∼20% greater (P < 0.05) in the obese group but not different after normalizing for the higher, albeit, nonsignificant differences in workloads (MVC: obese: 24 ± 5 kg, non-obese: 21 ± 5 kg, P = 0.11). Vascular conductance and the brachial artery shear-induced vasodilatory response during HG were not different between groups (P > 0.05). Taken together, despite elevated SBP during HG exercise, obesity does not lead to additional impairments in vascular function and peripheral exercising hemodynamics in patients with HTN. Obesity may not be a contraindication when prescribing exercise for the treatment of HTN among middle-aged adults, however, the elevated SBP should be appropriately monitored.NEW & NOTEWORTHY This study examined vascular function and handgrip exercise hemodynamics in obese and nonobese individuals with hypertension. Obesity, when combined with hypertension, was neither associated with additional vascular function impairments at baseline nor peripheral hemodynamics and vasodilation during exercise compared with nonobese hypertension. Interestingly, systolic blood pressure and pulse pressure were greater in the obese group during supine baseline and exercise. These findings should not be ignored and may be particularly important for rehabilitation strategies.
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Affiliation(s)
- Stephen M Ratchford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veteran Affairs Medical Center, Salt Lake City, Utah, United States
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veteran Affairs Medical Center, Salt Lake City, Utah, United States
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah, United States
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Oh Sung Kwon
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah, United States
- Department of Kinesiology, University of Connecticut, Storrs, Connecticut, United States
| | - Paul N Hopkins
- Department of Internal Medicine, Division of Cardiovascular Genetics, University of Utah, Salt Lake City, Utah, United States
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veteran Affairs Medical Center, Salt Lake City, Utah, United States
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veteran Affairs Medical Center, Salt Lake City, Utah, United States
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
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Mañago MM, Cohen ET, Alvarez E, Hager ER, Owens JG, Bade M. Feasibility of Low-Load Resistance Training Using Blood Flow Restriction for People With Advanced Multiple Sclerosis: A Prospective Cohort Study. Phys Ther 2024; 104:pzad135. [PMID: 37815934 PMCID: PMC10822774 DOI: 10.1093/ptj/pzad135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 06/03/2023] [Accepted: 08/05/2023] [Indexed: 10/12/2023]
Abstract
OBJECTIVE The objective of this study was to determine the feasibility of low-load resistance training with blood flow restriction (BFR) for people with advanced disability due to multiple sclerosis (MS). METHODS In this prospective cohort study, 14 participants with MS (Expanded Disability Status Scale [EDSS] score = 6.0 to 7.0; mean age = 55.4 [SD = 6.2] years; 71% women) were asked to perform 3 lower extremity resistance exercises (leg press, calf press, and hip abduction) bilaterally twice weekly for 8 weeks using BFR. Feasibility criteria were as follows: enrollment of 20 participants, ≥80% retention and adherence, ≥90% satisfaction, and no serious adverse events related to the intervention. Other outcomes included knee extensor, ankle plantar flexor, and hip abductor muscle strength, 30-Second Sit-to-Stand Test, Berg Balance Scale, Timed 25-Foot Walk Test, 12-Item MS Walking Scale, Modified Fatigue Impact Scale, Patient-Specific Functional Scale, and daily step count. RESULTS Sixteen participants consented, and 14 completed the intervention, with 93% adherence overall. All participants were satisfied with the intervention. A minor hip muscle strain was the only intervention-related adverse event. There were muscle strength improvements on the more-involved (16%-28%) and less-involved (12%-19%) sides. There were also changes in the 30-Second Sit-to-Stand Test (1.9 repetitions; 95% CI = 1.0 to 2.8), Berg Balance Scale (5.3 points; 95% CI = 3.2 to 7.4), Timed 25-Foot Walk Test (-3.3 seconds; 95% CI = -7.9 to 1.3), Modified Fatigue Impact Scale (-8.8 points; 95% CI = -16.5 to -1.1), 12-Item MS Walking Scale (-3.6 points; 95% CI = -11.5 to 4.4), Patient-Specific Functional Scale (2.9 points; 95% CI = 1.9 to 3.8), and daily step count (333 steps; 95% CI = -191 to 857). CONCLUSION Low-load resistance training using BFR in people with MS and EDSS scores of 6.0 to 7.0 appears feasible, and subsequent investigation into its efficacy is warranted. IMPACT Although efficacy data are needed, combining BFR with low-load resistance training may be a viable alternative for people who have MS and who do not tolerate conventional moderate- to high-intensity training because of more severe symptoms, such as fatigue and weakness. LAY SUMMARY Low-load strength training with BFR was feasible in people who have advanced disability due to MS. Using BFR may provide an alternative for people with MS who do not tolerate higher intensity training due to more severe symptoms, such as fatigue and weakness.
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Affiliation(s)
- Mark M Mañago
- Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Neurology, School of Medicine, University of Colorado, Aurora, Colorado, USA
- VA Eastern Colorado Healthcare System, Aurora, Colorado, USA
| | - Evan T Cohen
- Department of Physical Therapy, Arcadia University, Glenside, Pennsylvania, USA
| | - Enrique Alvarez
- Department of Neurology, School of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Emily R Hager
- Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- VA Eastern Colorado Healthcare System, Aurora, Colorado, USA
| | | | - Michael Bade
- Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- VA Eastern Colorado Healthcare System, Aurora, Colorado, USA
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Hartmann JP, Krabek R, Nymand SB, Hartmeyer H, Gliemann L, Berg RMG, Iepsen UW. Doppler Ultrasound-Based Leg Blood Flow Assessment During Single-Leg Knee-Extensor Exercise in an Uncontrolled Setting. J Vis Exp 2023. [PMID: 38163264 DOI: 10.3791/65746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024] Open
Abstract
Doppler ultrasound has revolutionized the assessment of organ blood flow and is widely used in research and clinical settings. While Doppler ultrasound-based assessment of contracting leg muscle blood flow is common in human studies, the reliability of this method requires further investigation. Therefore, this study aimed to investigate the within-day test-retest, between-day test-retest, and inter-rater reliability of Doppler ultrasound for assessing leg blood flow during rest and graded single-leg knee-extensions (0 W, 6 W, 12 W, and 18 W), with the ultrasound probe being removed between measurements. The study included thirty healthy subjects (age: 33 ± 9.3, male/female: 14/16) who visited the laboratory on two different experimental days separated by 10 days. The study did not control for major confounders such as nutritional state, time of day, or hormonal status. Across different exercise intensities, the results demonstrated high within-day reliability with a coefficient of variation (CV) ranging from 4.0% to 4.3%, acceptable between-day reliability with a CV ranging from 10.1% to 20.2%, and inter-rater reliability with a CV ranging from 17.9% to 26.8%. Therefore, in a real-life clinical scenario where controlling various environmental factors is challenging, Doppler ultrasound can be used to determine leg blood flow during submaximal single-leg knee-extensor exercise with high within-day reliability and acceptable between-day reliability when performed by the same sonographer.
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Affiliation(s)
- Jacob Peter Hartmann
- Centre for Physical Activity Research, Copenhagen University Hospital; Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen;
| | - Rikke Krabek
- Centre for Physical Activity Research, Copenhagen University Hospital
| | - Stine B Nymand
- Centre for Physical Activity Research, Copenhagen University Hospital; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen
| | - Helene Hartmeyer
- Centre for Physical Activity Research, Copenhagen University Hospital
| | - Lasse Gliemann
- Department of Nutrition, Exercise and Sports, Integrated Physiology Group
| | - Ronan M G Berg
- Centre for Physical Activity Research, Copenhagen University Hospital; Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen; Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales
| | - Ulrik Winning Iepsen
- Centre for Physical Activity Research, Copenhagen University Hospital; Department of Anaesthesiology and Intensive Care, Copenhagen University Hospital, Hvidovre Hospital
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Takahashi N, Sato K, Kiyota N, Yamazaki M, Kunikane E, Nakazawa T. The effect of a brinzolamide/brimonidine fixed combination on optic nerve head blood flow in rabbits. PLoS One 2023; 18:e0295122. [PMID: 38051718 DOI: 10.1371/journal.pone.0295122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/14/2023] [Indexed: 12/07/2023] Open
Abstract
PURPOSE The purpose of this study was to investigate the effect of a 1% brinzolamide and 0.1% brimonidine fixed combination (BBFC) on ONH blood flow (BF) in rabbits. METHODS A crossover study was conducted on pigmented rabbits; a physiological saline solution, brinzolamide, or BBFC was administered for eight days. ONH BF, intraocular pressure (IOP) and systemic parameters were measured before the eighth day's first dose and at 6, 9, 12, and 14 hours after the dose. ONH BF was assessed using laser speckle flowgraphy, and mean blur rate (MBR) values were calculated. The percentage against baseline of each parameter was calculated, and intergroup comparisons were performed at each time point. RESULTS There were no significant differences in the percentage change in systemic parameters. At 6 hours after administration, the BBFC group showed a significantly higher percentage change in large vessel area-MBR (%MV) compared to the control group (98.6±16.8%MV vs. 81.3±7.9%MV, P = 0.03). On the other hand, the brinzolamide group did not show a significant difference. Both the brinzolamide and BBFC groups had significantly lower percentage change in IOP (%IOP) compared to the control group (90.6±5.0%IOP, 93.3±2.9%IOP, and 99.2±1.7%IOP, respectively, P < 0.01). CONCLUSION BBFC effectively reduces IOP and mitigates diurnal fluctuation-induced decreases in ONH BF.
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Affiliation(s)
- Nana Takahashi
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Kota Sato
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Naoki Kiyota
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Mai Yamazaki
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
- Seiryo Eye Clinic, Miyagi, Japan
| | - Eriko Kunikane
- Department of Research and Development Division, Senju Pharmaceutical Co., Ltd., Osaka, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Miyagi, Japan
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Ogrezeanu DC, López-Bueno L, Sanchís-Sánchez E, Suso-Martí L, López-Bueno R, Núñez-Cortés R, Cruz-Montecinos C, Pérez-Alenda S, Casaña J, Gargallo P, Calatayud J. Exercise-induced hypoalgesia with end-stage knee osteoarthritis during different blood flow restriction levels: Sham-controlled crossover study. PM R 2023; 15:1565-1573. [PMID: 37796567 DOI: 10.1002/pmrj.13076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 09/08/2023] [Accepted: 10/02/2023] [Indexed: 10/06/2023]
Abstract
BACKGROUND Blood flow restriction (BFR) training could be a valuable treatment to induce exercise-induced hypoalgesia (EIH) in patients with end-stage knee osteoarthritis. However, the use of BFR in these patients is poorly explored and there is no evidence about the training dosage needed. OBJECTIVE To evaluate the effect of resistance training protocols with different occlusion levels of blood flow restriction (BFR) on EIH in patients with end-stage knee osteoarthritis. DESIGN Crossover study. SETTING University physical exercise laboratory. PARTICIPANTS 26 adults with end-stage knee osteoarthritis. INTERVENTIONS Patients performed four sets (30, 15, 15, and 15 repetitions) separated by 1-minute rests of three protocols/sessions of low-load (30% one-repetition-maximum) seated knee extensions with elastic bands and BFR: placebo (sham BFR), BFR at 40% arterial occlusion pressure (AOP) and BFR at 80% AOP. MAIN OUTCOME MEASURES Pressure Pain Thresholds (PPT) and Visual Analog Scale (VAS) collected before, immediately after session, and after 10 minutes. RESULTS No differences in EIH were found between the different levels of BFR. However, 80% AOP protocol worsened VAS scores immediately (mean difference [MD]: -21.2 (95% confidence interval [CI] -33.9 to -8.5) while improving PPT immediately (MD affected limb: -.6 [95% CI -1.1 to -.2]); contralateral: -.6 (95% CI -1.0 to -.2]) and at 10 minutes (MD affected limb: -.6 [95% CI) -1.2 to -.1]; contralateral: -.7 [95% CI -1.1 to -.2]; and forearm: -.5 [95% CI -.9 to -.05]) post-exercise compared to baseline. CONCLUSIONS There is no EIH difference after using different occlusion levels. EIH is modulated by pain-related psychological constructs and self-perceived health status.
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Affiliation(s)
- Daniel C Ogrezeanu
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - Laura López-Bueno
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - Enrique Sanchís-Sánchez
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - Luis Suso-Martí
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - Rubén López-Bueno
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
- National Research Centre for the Working Environment, Copenhagen, Denmark
- Department of Physical Medicine and Nursing, University of Zaragoza, Zaragoza, Spain
| | - Rodrigo Núñez-Cortés
- Physiotherapy in Motion Multispeciality Research Group (PTinMOTION), Department of Physiotherapy, University of Valencia, Valencia, Spain
- Laboratory of Clinical Biomechanics, Department of Physical Therapy, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Carlos Cruz-Montecinos
- Physiotherapy in Motion Multispeciality Research Group (PTinMOTION), Department of Physiotherapy, University of Valencia, Valencia, Spain
- Laboratory of Clinical Biomechanics, Department of Physical Therapy, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Sofía Pérez-Alenda
- Physiotherapy in Motion Multispeciality Research Group (PTinMOTION), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - José Casaña
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
| | - Pedro Gargallo
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
- Department of Physiotherapy, Faculty of Medicine and Health Science, Catholic University of Valencia, Valencia, Spain
| | - Joaquín Calatayud
- Exercise Intervention for Health Research Group (EXINH-RG), Department of Physiotherapy, University of Valencia, Valencia, Spain
- National Research Centre for the Working Environment, Copenhagen, Denmark
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Heeman W, Calon J, van der Bilt A, Pierie JPEN, Pereboom I, van Dam GM, Boerma EC. Dye-free visualisation of intestinal perfusion using laser speckle contrast imaging in laparoscopic surgery: a prospective, observational multi-centre study. Surg Endosc 2023; 37:9139-9146. [PMID: 37814165 PMCID: PMC10709216 DOI: 10.1007/s00464-023-10493-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/23/2023] [Indexed: 10/11/2023]
Abstract
INTRODUCTION Intraoperative perfusion imaging may help the surgeon in creating the intestinal anastomoses in optimally perfused tissue. Laser speckle contrast imaging (LSCI) is such a perfusion visualisation technique that is characterized by dye-free, real-time and continuous imaging. Our aim is to validate the use of a novel, dye-free visualization tool to detect perfusion deficits using laparoscopic LSCI. METHODS In this multi-centre study, a total of 64 patients were imaged using the laparoscopic laser speckle contrast imager. Post-operatively, surgeons were questioned if the additional visual feedback would have led to a change in clinical decision-making. RESULTS This study suggests that the laparoscopic laser speckle contrast imager PerfusiX-Imaging is able to image colonic perfusion. All images were clear and easy to interpret for the surgeon. The device is non-disruptive of the surgical procedure with an average added surgical time of 2.5 min and no change in surgical equipment. The potential added clinical value is accentuated by the 17% of operating surgeons indicating a change in anastomosis location. Further assessment and analysis of both white light and PerfusiX perfusion images by non-involved, non-operating surgeons showed an overall agreement of 80%. CONCLUSION PerfusiX-Imaging is a suitable laparoscopic perfusion imaging system for colon surgery that can visualize perfusion in real-time with no change in surgical equipment. The additional visual feedback could help guide the surgeons in placing the anastomosis at the most optimal site.
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Affiliation(s)
- Wido Heeman
- Faculty Campus Fryslân, University of Groningen, Wirdumerdijk 34, 8911 CE, Leeuwarden, The Netherlands.
- Department of Surgery, University Medical Centre Groningen, 9713 GZ, Groningen, The Netherlands.
- LIMIS Development BV, 8934 AD, Leeuwarden, The Netherlands.
| | - Joost Calon
- ZiuZ Visual Intelligence BV, 8401 DK, Gorredijk, The Netherlands
| | - Arne van der Bilt
- Department of Surgery, University Medical Centre Groningen, 9713 GZ, Groningen, The Netherlands
| | - Jean-Pierre E N Pierie
- Medical Center Leeuwarden, Department of Surgery, 8934 AD, Leeuwarden, The Netherlands
- Post Graduate School of Medicine, University Medical Center Groningen, 9713 GZ, Groningen, The Netherlands
| | - Ilona Pereboom
- Department of Surgery, Nij Smellinghe Hospital, 9202 NN, Drachten, The Netherlands
| | - Gooitzen M van Dam
- Department of Surgery, University Medical Centre Groningen, 9713 GZ, Groningen, The Netherlands
| | - E Christiaan Boerma
- Department of Intensive Care, Medical Center Leeuwarden, 8934 AD, Leeuwarden, The Netherlands
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Lazaridis C. Cerebral blood flow after thoracoabdominal normothermic regional perfusion: Fundamental yet underexplored. J Heart Lung Transplant 2023; 42:1764-1765. [PMID: 37683893 DOI: 10.1016/j.healun.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 09/02/2023] [Indexed: 09/10/2023] Open
Affiliation(s)
- Christos Lazaridis
- Department of Neurology, University of Chicago, Chicago, Illinois; Department of Neurosurgery, University of Chicago, Chicago, Illinois; MacLean Center for Clinical Medical Ethics at the University of Chicago, Chicago, Illinois.
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Courish MK, Shivgulam ME, MacLeod JR, Kimmerly DS, O'Brien MW. Impact of unilateral dual-brachial arteries on endothelial-dependent and endothelial-independent vasodilation: a case study. Appl Physiol Nutr Metab 2023; 48:1019-1022. [PMID: 37586105 DOI: 10.1139/apnm-2023-0170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
TAKE HOME MESSAGE Our case study indicated that a bifurcated brachial artery exhibited worse vasodilatory responses relative to an intact contralateral artery.
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Affiliation(s)
- Molly K Courish
- Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS,Canada
| | - Madeline E Shivgulam
- Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS,Canada
| | - Jessica R MacLeod
- Diagnostic Medical Ultrasound, Faculty of Health Sciences, Dalhousie University, Halifax, NS, Canada
| | - Derek S Kimmerly
- Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS,Canada
| | - Myles W O'Brien
- School of Physiotherapy (Faculty of Health) and Department of Medicine (Faculty of Medicine), Dalhousie University, Halifax, NS, Canada
- Geriatric Medicine Research, Dalhousie University & Nova Scotia Health, Halifax, NS, Canada
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González Olmos A, Zilpelwar S, Sunil S, Boas DA, Postnov DD. Optimizing the precision of laser speckle contrast imaging. Sci Rep 2023; 13:17970. [PMID: 37864006 PMCID: PMC10589309 DOI: 10.1038/s41598-023-45303-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 10/18/2023] [Indexed: 10/22/2023] Open
Abstract
Laser speckle contrast imaging (LSCI) is a rapidly developing technology broadly applied for the full-field characterization of tissue perfusion. Over the recent years, significant advancements have been made in interpreting LSCI measurements and improving the technique's accuracy. On the other hand, the method's precision has yet to be studied in detail, despite being as important as accuracy for many biomedical applications. Here we combine simulation, theory and animal experiments to systematically evaluate and re-analyze the role of key factors defining LSCI precision-speckle-to-pixel size ratio, polarisation, exposure time and camera-related noise. We show that contrary to the established assumptions, smaller speckle size and shorter exposure time can improve the precision, while the camera choice is less critical and does not affect the signal-to-noise ratio significantly.
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Affiliation(s)
| | - Sharvari Zilpelwar
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Smrithi Sunil
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - David A Boas
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Dmitry D Postnov
- Department of Clinical Medicine, Aarhus University, 8200, Aarhus, Denmark.
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Ghouse A, Candia-Rivera D, Valenza G. Nonlinear neural patterns are revealed in high frequency functional near infrared spectroscopy analysis. Brain Res Bull 2023; 203:110759. [PMID: 37716513 DOI: 10.1016/j.brainresbull.2023.110759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/29/2023] [Accepted: 09/11/2023] [Indexed: 09/18/2023]
Abstract
Functional Near Infrared Spectroscopy (fNIRS) is a useful tool for measuring hemoglobin concentration. Linear theory of the hemodynamic response function supports low frequency analysis (<0.2 Hz). However, we hypothesized that nonlinearities, arising from the complex neurovascular interactions sustaining vasomotor tone, may be revealed in higher frequency components of fNIRS signals. To test this hypothesis, we simulated nonlinear hemodynamic models to explore how blood flow autoregulation changes may alter evoked neurovascular signals in high frequencies. Next, we analyzed experimental fNIRS data to compare neural representations between fast (0.2-0.6 Hz) and slow (<0.2 Hz) waves, demonstrating that only nonlinear representations quantified by sample entropy are distinct between these frequency bands. Finally, we performed group-level distance correlation analysis to show that the cortical distribution of activity is independent only in the nonlinear analysis of fast and slow waves. Our study highlights the importance of analyzing nonlinear higher frequency effects seen in fNIRS for a comprehensive analysis of cortical neurovascular activity. Furthermore, it motivates further exploration of the nonlinear dynamics driving regional blood flow and hemoglobin concentrations.
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Affiliation(s)
- Ameer Ghouse
- Bioengineering and Robotics Research Center "E. Piaggio", School of Engineering, University of Pisa, Italy.
| | - Diego Candia-Rivera
- Sorbonne Université, Paris Brain Institute (ICM), INRIA, CNRS, INSERM, AP-HP, Hôpital Pitié-Salpêtrière, Paris, France
| | - Gaetano Valenza
- Department of Information Engineering, School of Engineering, University of Pisa, Italy; Bioengineering and Robotics Research Center "E. Piaggio", School of Engineering, University of Pisa, Italy.
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Noureldine AM, Abdelmaksoud AMS, Mostafa HAAF, Macky T, ElBohy AE. Orbital blood vessels changes on color duplex imaging in diabetics with and without diabetic retinopathy. Sci Rep 2023; 13:17115. [PMID: 37816787 PMCID: PMC10564715 DOI: 10.1038/s41598-023-43838-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 09/28/2023] [Indexed: 10/12/2023] Open
Abstract
To compare changes in ophthalmic artery (OA) and its branches in diabetics with and without diabetic retinopathy (DR) using color duplex imaging (CDI), and to correlate these changes with the disease variables. 60 eyes of 60 diabetic patients were enrolled, divided into 3 groups: without DR (Group A), with Non-Proliferative DR (Group B) and with Proliferative DR (PDR) (Group C). Laboratory testing including HbA1c was done. Patients underwent CDI, by which OA, Central Retinal Artery (CRA) and Ciliary Arteries were identified; for each of them we measured Peak systolic velocity (PSV), End Diastolic velocity (EDV) and Resistivity Index (RI). Results were compared to clinical, laboratory and fundus examination. OA EDV was significantly lower and OA RI was found to be significantly higher in Group C (p = 0.027 and 0.025 respectively). CRA PSV and EDV were significantly lower in Group C (p = 0.017 and 0.001 respectively). PCA RI was significantly higher in Group C (p = 0.008). HbA1c was negatively correlated with CRA PSV (p = 0.041), also it was negatively correlated with CRA EDV (p = 0.0001), as well as with PCA EDV (p = 0.002). There was direct significant correlation between HbA1c and PCA RI (p = 0.012). Duration since diagnosis was negatively correlated with CRA EDV (p = 0.004). Multivariate linear regression showed that DR is an independent predictor for low OA EDV, high OA RI, low CRA EDV and high PCA RI. DR is an independent risk factor for orbital and ocular vessels flow alteration, thus can be used as a prognostic tool in diabetic patients. CDI can be reliably used in diabetics to predict early changes or progression of DR.
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Affiliation(s)
- Alia M Noureldine
- Ophthalmology Department, Kasr Alainy School of Medicine, Cairo University, Cairo, 11956, Egypt.
| | | | | | - Tamer Macky
- Ophthalmology Department, Kasr Alainy School of Medicine, Cairo University, Cairo, 11956, Egypt
| | - Abo Elmagd ElBohy
- Diagnostic and Interventional Radiology, Kasr Alainy School of Medicine, Cairo University, Cairo, Egypt
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Martin ZT, Al-Daas IO, Cardenas N, Kolade JO, Merlau ER, Vu JK, Brown KK, Brothers RM. Peripheral and Cerebral Vasodilation in Black and White Women: Examining the Impact of Psychosocial Stress Exposure Versus Internalization and Coping. Hypertension 2023; 80:2122-2134. [PMID: 37534492 PMCID: PMC10530116 DOI: 10.1161/hypertensionaha.123.21230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/10/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND Black women have among the highest rates of cardiovascular and cerebrovascular disease prevalence and mortality in part due to blunted vascular function. Psychosocial stress likely also contributes but its relationship to vascular function remains incompletely understood. Recent studies suggest that stress internalization and coping strategies are more important than stress exposures alone. We hypothesized that Black women would have blunted peripheral and cerebral vasodilation and that, among Black women, this would be inversely related with psychosocial stress internalization/coping but not stress exposures. METHODS Healthy Black (n=21; 20±2 years) and White (n=16; 25±7 years) women underwent testing for forearm reactive hyperemia, brachial artery flow-mediated dilation (FMD), and cerebrovascular reactivity. Psychosocial stress exposures (adverse childhood experiences; past week discrimination) and internalization/coping techniques (John Henryism Active Coping Scale; Giscombe Superwoman Schema Questionnaire) were assessed. RESULTS Reactive hyperemia and cerebrovascular reactivity were not different between groups (P>0.05), whereas FMD was lower in Black women (P=0.007). Neither adverse childhood experiences nor past week discrimination were associated with FMD in either group (P>0.05 for all). John Henryism Active Coping Scale scores were negatively associated with FMD in Black women (P=0.014) but positively associated with FMD in White women (P=0.042). Superwoman Schema-Succeed was negatively associated (P=0.044) and Superwoman Schema-Vulnerable tended to be negatively associated (P=0.057) with FMD in Black women. CONCLUSIONS These findings indicate that blunted FMD in Black women may be due more to stress internalization and maladaptive coping than stress exposures alone.
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Affiliation(s)
- Zachary T Martin
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - Iman O Al-Daas
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - Natalia Cardenas
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - John O Kolade
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - Emily R Merlau
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - Joshua K Vu
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - Kyrah K Brown
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
| | - R Matthew Brothers
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX
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Mezentseva LV. Asymmetry of Characteristics of the Right-Left Hemodynamic Balance of Microcirculation in the Temporal Skin Areas of the Head in Young Male and Female Subjects. Bull Exp Biol Med 2023; 175:734-738. [PMID: 37978150 DOI: 10.1007/s10517-023-05935-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Indexed: 11/19/2023]
Abstract
The indices of asymmetry of microcirculation in the skin of the temporal areas of the head in young male and female subjects were studied. In 20 healthy volunteers (10 men and 10 women, age 18-19 years), synchronous measurements of the microcirculation of the skin of the symmetrical temporal areas of the head were carried out by laser Doppler flowmetry. The coefficients of asymmetry of regression relationships between perfusion changes in each side and initial perfusion values in both the same and opposite sides, the distribution function of perfusion asymmetry coefficients, and variability of perfusion in the studied areas were analyzed. The sex differences of the measured characteristics of asymmetry were revealed. In men, the distribution functions of perfusion asymmetry are pointed, with positive excesses, and in women they were flat, with negative excesses. In female subjects, the contribution of the right microcirculatory bed to the right-left hemodynamic balance was higher. These findings support the hypothesis on greater plasticity of the female brain in comparison with the male brain.
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Affiliation(s)
- L V Mezentseva
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.
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Fayed HS, Bakleh MZ, Ashraf JV, Howarth A, Ebner D, Al Haj Zen A. Selective ROCK Inhibitor Enhances Blood Flow Recovery after Hindlimb Ischemia. Int J Mol Sci 2023; 24:14410. [PMID: 37833857 PMCID: PMC10572734 DOI: 10.3390/ijms241914410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 10/15/2023] Open
Abstract
The impairment in microvascular network formation could delay the restoration of blood flow after acute limb ischemia. A high-content screen of a GSK-published kinase inhibitor library identified a set of ROCK inhibitor hits enhancing endothelial network formation. Subsequent kinase activity profiling against a panel of 224 protein kinases showed that two indazole-based ROCK inhibitor hits exhibited high selectivity for ROCK1 and ROCK2 isoforms compared to other ROCK inhibitors. One of the chemical entities, GSK429286, was selected for follow-up studies. We found that GSK429286 was ten times more potent in enhancing endothelial tube formation than Fasudil, a classic ROCK inhibitor. ROCK1 inhibition by RNAi phenocopied the angiogenic phenotype of the GSK429286 compound. Using an organotypic angiogenesis co-culture assay, we showed that GSK429286 formed a dense vascular network with thicker endothelial tubes. Next, mice received either vehicle or GSK429286 (10 mg/kg i.p.) for seven days after hindlimb ischemia induction. As assessed by laser speckle contrast imaging, GSK429286 potentiated blood flow recovery after ischemia induction. At the histological level, we found that GSK429286 significantly increased the size of new microvessels in the regenerating areas of ischemic muscles compared with vehicle-treated ones. Our findings reveal that selective ROCK inhibitors have in vitro pro-angiogenic properties and therapeutic potential to restore blood flow in limb ischemia.
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Affiliation(s)
- Hend Salah Fayed
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha P.O. Box 34110, Qatar
| | - Mouayad Zuheir Bakleh
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha P.O. Box 34110, Qatar
| | | | - Alison Howarth
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Daniel Ebner
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford OX3 7FZ, UK
| | - Ayman Al Haj Zen
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha P.O. Box 34110, Qatar
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK
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Kositanurit W, Korakot M, Burana C, Varachotisate P, Kerr SJ, Boonla C, Kulaputana O. Acute effect of various dosages of sugar ingestion on vascular function in offspring of hypertensive and normotensive parents. J Hypertens 2023; 41:1485-1492. [PMID: 37432905 DOI: 10.1097/hjh.0000000000003500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
OBJECTIVES We aimed to study vascular function in healthy men with a parental history of hypertension compared to those without. Acute effect of various dosages of sugar ingestion on vascular function was also investigated in both groups. METHODS Thirty-two healthy men were recruited and divided into two groups, offspring of hypertensive parents (OHT) and offspring of normotensive parents (ONT). Participants were orally given 15, 30, and 60 g of sucrose solution compared to water. Peak forearm blood flow (FBF), forearm vascular resistance (FVR), pulse wave velocity (PWV), and oxidative stress markers were measured at baseline and after sucrose intake at 30, 60, 90, and 120 min. RESULTS At baseline, peak FBF was significantly lower (22.40 ± 1.18 vs. 25.24 ± 0.63 ml × dl -1 × min -1 , P < 0.001), FVR was significantly higher (3.73 ± 0.42 vs. 3.30 ± 0.26 mmHg × ml -1 × dl × min, P = 0.002), and PWV was significantly faster (6.31 ± 0.59 vs. 5.78 ± 0.61 m/s, P = 0.017) in OHT than ONT. After each sucrose intake, peak FBF significantly declined and was lowest at 30 min in both groups. The reduction in peak FBF was seen in all doses of sucrose and the higher dose of sucrose intervened, the longer reduction in peak FBF observed. CONCLUSIONS Vascular function was attenuated in healthy men with a family history of hypertension and became worse after sucrose ingestion even at the low dose. Our findings suggest that the ones, especially those with a parental history of hypertension, should reduce sugar consumption as low as possible.
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Affiliation(s)
- Weerapat Kositanurit
- Department of Physiology, Faculty of Medicine, Chulalongkorn University
- King Chulalongkorn Memorial Hospital, Thai Red Cross Society
| | - Manta Korakot
- Interdepartment of Physiology program, Chulalongkorn University
| | - Chuti Burana
- Department of Physiology, Faculty of Medicine, Chulalongkorn University
- King Chulalongkorn Memorial Hospital, Thai Red Cross Society
| | - Pachara Varachotisate
- Department of Physiology, Faculty of Medicine, Chulalongkorn University
- King Chulalongkorn Memorial Hospital, Thai Red Cross Society
| | | | - Chanchai Boonla
- King Chulalongkorn Memorial Hospital, Thai Red Cross Society
- Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Onanong Kulaputana
- Department of Physiology, Faculty of Medicine, Chulalongkorn University
- King Chulalongkorn Memorial Hospital, Thai Red Cross Society
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Liu YZ, Mehrotra S, Buharin VE, Marois M, Nwaiwu CA, Wilson EB, Kim PCW. Dye-Less Perfusion Quantification of Porcine Gastric Conduit with Laser Speckle Contrast Imaging and Laser Doppler Imaging. J Gastrointest Surg 2023; 27:1947-1949. [PMID: 37227609 DOI: 10.1007/s11605-023-05708-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/01/2023] [Indexed: 05/26/2023]
Affiliation(s)
- Yao Z Liu
- Department of Surgery, Brown University, Providence, RI, USA
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Saloni Mehrotra
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
- Department of Surgery, University at Buffalo, NY, Buffalo, USA
| | - Vasiliy E Buharin
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Mikael Marois
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Chibueze A Nwaiwu
- Department of Surgery, Brown University, Providence, RI, USA
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Erik B Wilson
- University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Peter C W Kim
- Department of Surgery, Brown University, Providence, RI, USA.
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA.
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Mannozzi J, Al-Hassan MH, Kaur J, Lessanework B, Alvarez A, Massoud L, Aoun K, Spranger M, O'Leary DS. Blood flow restriction training activates the muscle metaboreflex during low-intensity sustained exercise. J Appl Physiol (1985) 2023; 135:260-270. [PMID: 37348015 PMCID: PMC10393340 DOI: 10.1152/japplphysiol.00274.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 06/09/2023] [Indexed: 06/24/2023] Open
Abstract
Blood flow restriction training (BFRT) employs partial vascular occlusion of exercising muscle and has been shown to increase muscle performance while using reduced workload and training time. Numerous studies have demonstrated that BFRT increases muscle hypertrophy, mitochondrial function, and beneficial vascular adaptations. However, changes in cardiovascular hemodynamics during the exercise protocol remain unknown, as most studies measured blood pressure before the onset and after the cessation of exercise. With reduced perfusion to the exercising muscle during BFRT, the resultant accumulation of metabolites within the ischemic muscle could potentially trigger a large reflex increase in blood pressure, termed the muscle metaboreflex. At low workloads, this pressor response occurs primarily via increases in cardiac output. However, when increases in cardiac output are limited (e.g., heart failure or during severe exercise), the reflex shifts to peripheral vasoconstriction as the primary mechanism to increase blood pressure, potentially increasing the risk of a cardiovascular event. Using our chronically instrumented conscious canine model, we utilized a 60% reduction in femoral blood pressure applied to the hindlimbs during steady-state treadmill exercise (3.2 km/h) to reproduce the ischemic environment observed during BFRT. We observed significant increases in heart rate (+19 ± 3 beats/min), stroke volume (+2.52 ± 1.2 mL), cardiac output (+1.21 ± 0.2 L/min), mean arterial pressure (+18.2 ± 2.4 mmHg), stroke work (+1.93 ± 0.2 L/mmHg), and nonischemic vascular conductance (+3.62 ± 1.7 mL/mmHg), indicating activation of the muscle metaboreflex.NEW & NOTEWORTHY Blood flow restriction training (BFRT) increases muscle mass, strength, and endurance. There has been minimal consideration of the reflex cardiovascular responses that could be elicited during BFRT sessions. We showed that during low-intensity exercise BFRT may trigger large reflex increases in blood pressure and sympathetic activity due to muscle metaboreflex activation. Thus, we urge caution when employing BFRT, especially in patients in whom exaggerated cardiovascular responses may occur that could cause sudden, adverse cardiovascular events.
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Affiliation(s)
- Joseph Mannozzi
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Mohamed-Hussein Al-Hassan
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Jasdeep Kaur
- Department of Kinesiology and Health Education, University of Texas at Austin, Austin, Texas, United States
| | - Beruk Lessanework
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Alberto Alvarez
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Louis Massoud
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Kamel Aoun
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Marty Spranger
- Department of Physiology, Michigan State University, East Lansing, Michigan, United States
| | - Donal S O'Leary
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States
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Rizk AA, Dybala MP, Rodriguez KC, Slak Rupnik M, Hara M. Pancreatic regional blood flow links the endocrine and exocrine diseases. J Clin Invest 2023; 133:e166185. [PMID: 37338995 PMCID: PMC10378168 DOI: 10.1172/jci166185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 06/16/2023] [Indexed: 06/22/2023] Open
Abstract
An increasing number of studies have demonstrated that disease states of the endocrine or exocrine pancreas aggravate one another, which implies bidirectional blood flow between islets and exocrine cells. However, this is inconsistent with the current model of unidirectional blood flow, which is strictly from islets to exocrine tissues. This conventional model was first proposed in 1932, and it has never to our knowledge been revisited to date. Here, large-scale image capture was used to examine the spatial relationship between islets and blood vessels in the following species: human, monkey, pig, rabbit, ferret, and mouse. While some arterioles passed by or traveled through islets, the majority of islets had no association with them. Islets with direct contact with the arteriole were significantly larger in size and fewer in number than those without contact. Unique to the pancreas, capillaries directly branched out from the arterioles and have been labeled as "small arterioles" in past studies. Overall, the arterioles emerged to feed the pancreas regionally, not specifically targeting individual islets. Vascularizing the pancreas in this way may allow an entire downstream region of islets and acinar cells to be simultaneously exposed to changes in the blood levels of glucose, hormones, and other circulating factors.
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Affiliation(s)
- Adam A. Rizk
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Michael P. Dybala
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA
| | | | - Marjan Slak Rupnik
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Manami Hara
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA
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Williams AC, Content VG, Kirby NV, Alexander LM. Intradermal Microdialysis: An Approach to Investigating Novel Mechanisms of Microvascular Dysfunction in Humans. J Vis Exp 2023. [PMID: 37548450 DOI: 10.3791/65579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/08/2023] Open
Abstract
The cutaneous vasculature is an accessible tissue that can be used to assess microvascular function in humans. Intradermal microdialysis is a minimally invasive technique used to investigate mechanisms of vascular smooth muscle and endothelial function in the cutaneous circulation. This technique allows for the pharmacological dissection of the pathophysiology of microvascular endothelial dysfunction as indexed by decreased nitric oxide-mediated vasodilation, an indicator of cardiovascular disease development risk. In this technique, a microdialysis probe is placed in the dermal layer of the skin, and a local heating unit with a laser Doppler flowmetry probe is placed over the probe to measure the red blood cell flux. The local skin temperature is clamped or stimulated with direct heat application, and pharmacological agents are perfused through the probe to stimulate or inhibit intracellular signaling pathways in order to induce vasodilation or vasoconstriction or to interrogate mechanisms of interest (co-factors, antioxidants, etc.). The cutaneous vascular conductance is quantified, and mechanisms of endothelial dysfunction in disease states can be delineated.
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Affiliation(s)
- Auni C Williams
- Department of Kinesiology, The Pennsylvania State University;
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Dolgyras P, Lazaridis A, Anyfanti P, Gavriilaki E, Koletsos N, Triantafyllou A, Nikolaidou B, Galanapoulou V, Douma S, Gkaliagkousi E. Microcirculation dynamics in systemic vasculitis: evidence of impaired microvascular response regardless of cardiovascular risk factors. Rheumatology (Oxford) 2023; 62:2510-2516. [PMID: 36394222 DOI: 10.1093/rheumatology/keac652] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/03/2022] [Indexed: 07/20/2023] Open
Abstract
OBJECTIVES Systemic vasculitides (SVs) are a highly inflammatory group of diseases characterized by significant cardiovascular (CV) mortality. Microvascular damage closely linked with accelerated atherosclerosis and thrombosis represents a core pathophysiological mechanism contributing to the excess CV risk of patients with SVs. Skin represents an easily accessible tissue facilitating non-invasive microvascular study. In this study we aimed to investigate microcirculation dynamics and associate them with disease-related factors in patients with SVs. METHODS We assessed skin microcirculation using laser speckle contrast imaging (LSCI) and vascular reactivity by the post-occlusive reactive hyperaemia (PORH) protocol in a meticulously selected group of patients with SVs without CV disease and compared them to controls, matched for age, sex, BMI and smoking status. RESULTS Sixty individuals were included in the study, 30 patients and 30 controls. Patients with SVs presented a lower peak magnitude during reperfusion phase (median [interquartile range] 207 [60.1] vs 143.7 [41.0] laser speckle perfusion units, P < 0.001) and lower percentage cutaneous vascular conductance increase (mean (s.d.) 190.0 [49.6]% vs 149.6 [48.9]%, P = 0.002) as compared with controls. Importantly, microvascular damage was correlated with disease duration (P < 0.001, r = -0.563 and P < 0.001, r = 0.442, respectively). CONCLUSION For the first time we have shown that patients with SVs exhibit impaired microvascular function and blunted reactivity after occlusion, as this was demonstrated by the LSCI technique. Therefore, skin microcirculation may be a useful, non-invasive method in patients with SVs for the early detection of microvascular dysfunction, which is closely related to the high CV risk that these patients bear.
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Affiliation(s)
- Panagiotis Dolgyras
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Antonios Lazaridis
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Panagiota Anyfanti
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Eleni Gavriilaki
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Nikolaos Koletsos
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Areti Triantafyllou
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Barbara Nikolaidou
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | - Stella Douma
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Eugenia Gkaliagkousi
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Babaei S, Dai B, Abbey CK, Ambreen Y, Dobrucki WL, Insana MF. Monitoring Muscle Perfusion in Rodents During Short-Term Ischemia Using Power Doppler Ultrasound. Ultrasound Med Biol 2023; 49:1465-1475. [PMID: 36967332 PMCID: PMC10106419 DOI: 10.1016/j.ultrasmedbio.2023.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 05/11/2023]
Abstract
OBJECTIVE The aim of this work was to evaluate the reliability of power Doppler ultrasound (PD-US) measurements made without contrast enhancement to monitor temporal changes in peripheral blood perfusion. METHODS On the basis of pre-clinical rodent studies, we found that combinations of spatial registration and clutter filtering techniques applied to PD-US signals reproducibly tracked blood perfusion in skeletal muscle. Perfusion is monitored while modulating hindlimb blood flow. First, in invasive studies, PD-US measurements in deep muscle with laser speckle contrast imaging (LSCI) of superficial tissues made before, during and after short-term arterial clamping were compared. Then, in non-invasive studies, a pressure cuff was employed to generate longer-duration hindlimb ischemia. Here, B-mode imaging was also applied to measure flow-mediated dilation of the femoral artery while, simultaneously, PD-US was used to monitor downstream muscle perfusion to quantify reactive hyperemia. Measurements in adult male and female mice and rats, some with exercise conditioning, were included to explore biological variables. RESULTS PD-US methods are validated through comparisons with LSCI measurements. As expected, no significant differences were found between sexes or fitness levels in flow-mediated dilation or reactive hyperemia estimates, although post-ischemic perfusion was enhanced with exercise conditioning, suggesting there could be differences between the hyperemic responses of conduit and resistive vessels. CONCLUSION Overall, we found non-contrast PD-US imaging can reliably monitor relative spatiotemporal changes in muscle perfusion. This study supports the development of PD-US methods for monitoring perfusion changes in patients at risk for peripheral artery disease.
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Affiliation(s)
- Somaye Babaei
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Bingze Dai
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Craig K Abbey
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA, USA
| | - Yamenah Ambreen
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Wawrzyniec L Dobrucki
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Biomedical and Translational Sciences, Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Michael F Insana
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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Montoye AHK, Neph SE, Plouffe AA, Vondrasek JD, Nordbeck JT, Cox BA, Vranish JR. Understanding lower limb blood flow occlusion parameters for use in field-based settings. J Sports Sci 2023; 41:850-858. [PMID: 37493083 DOI: 10.1080/02640414.2023.2240995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 07/18/2023] [Indexed: 07/27/2023]
Abstract
Reduction of blood flow to the limb using cuffs before or during exercise has become increasingly popular for training and rehabilitation. Our study tested the effects of cuff brand/width on pressures required to reach limb occlusion pressure (LOP) and developed, cross-validated, and compared accuracy of two LOP prediction equations to previously created methods. Supine LOP was determined in the distal popliteal artery using four different cuff brands/widths in 23 adult participants. Participants then had demographic and resting variables assessed, and two LOP prediction equations were developed from these variables and were compared to five previously developed models and a method using posterior tibial artery palpation for LOP assessment in an independent sample (n = 14 adult runners). For cuff comparison, the widest two cuffs had significantly lower LOP (mean ~149 mmHg) than the narrowest cuffs (mean ~176 mmHg), with the narrowest cuff unable to reach LOP. The eight methods used to predict LOP ranged in accuracy (mean absolute percent errors 3.9-23.0%), with highest accuracy in equations using mean arterial pressure (MAP) and BMI. Practitioners using blood flow reduction methods should be consistent with cuff use due to demonstrated differences across brands/widths. Equations using MAP and BMI appear best for prediction of leg LOP.
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Affiliation(s)
- Alexander H K Montoye
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
| | - Sylvia E Neph
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
| | - Audrey A Plouffe
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
| | - Joseph D Vondrasek
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
- Department of Health Sciences and Kinesiology, Georgia Southern University Armstrong Campus, Savannah, GA, United States of America
| | - Jackson T Nordbeck
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
| | - Benjamin A Cox
- Cox Sports Medicine and Orthopedic Surgery, Mt. Pleasant, MI, United States of America
| | - Jennifer R Vranish
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, United States of America
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Koshika K, Kaneko R, Shionoya M, Shimizu K, Sendai Y, Matsuura N, Akiike Y, Ichinohe T. Involvement of α- and β-Adrenergic Receptors in Skeletal Muscle Blood Flow Changes During Hyper-/Hypocapnia in Anesthetized Rabbits. Anesth Prog 2023; 70:58-64. [PMID: 37379094 PMCID: PMC10328189 DOI: 10.2344/anpr-70-02-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 01/23/2023] [Indexed: 06/29/2023] Open
Abstract
OBJECTIVE This study investigated the involvement of α1- and β2-adrenergic receptors in skeletal muscle blood flow changes during variations in ETCO2. METHODS Forty Japanese White rabbits anesthetized with isoflurane were randomly allocated to 1 of 5 groups: phentolamine, metaproterenol, phenylephrine, butoxamine, and atropine. Heart rate (HR), systolic blood pressure (SBP), common carotid artery blood flow (CCBF), masseter muscle tissue blood flow (MBF), and quadriceps muscle tissue blood flow (QBF) were recorded and analyzed at 3 periods: (1) baseline, (2) during hypercapnia (phentolamine and metaproterenol groups) or hypocapnia (phenylephrine, butoxamine, and atropine groups), and (3) during or after receiving vasoactive agents. RESULTS MBF and QBF decreased during hypercapnia. The decrease in MBF was smaller than that in QBF. SBP and CCBF increased, while HR decreased. Both MBF and QBF recovered to their baseline levels after phentolamine administration. MBF became greater than its baseline level, while QBF did not fully recover after metaproterenol administration. MBF and QBF increased during hypocapnia. The increase rate in MBF was larger than that in QBF. HR, SBP, and CCBF did not change. Both MBF and QBF decreased to ∼90% to 95% of their baseline levels after phenylephrine or butoxamine administration. Atropine showed no effects on MBF and QBF. CONCLUSION These results suggest the skeletal muscle blood flow changes observed during hypercapnia and hypocapnia may mainly involve α1-adrenergic but not β2-adrenergic receptor activity.
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Affiliation(s)
- Kyotaro Koshika
- Associate Professor, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Rumi Kaneko
- Postgraduate Student, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Mai Shionoya
- Postgraduate Student, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Kotaro Shimizu
- Postgraduate Student, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Yuka Sendai
- Postgraduate Student, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Nobutaka Matsuura
- Postgraduate Student, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Yui Akiike
- Senior Assistant Professor, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
| | - Tatsuya Ichinohe
- Professor and Chairman, Department of Dental Anesthesiology, Tokyo Dental College, Tokyo, Japan
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Chizari A, Tsong W, Knop T, Steenbergen W. Prediction of motion artifacts caused by translation in handheld laser speckle contrast imaging. J Biomed Opt 2023; 28:046005. [PMID: 37082096 PMCID: PMC10112282 DOI: 10.1117/1.jbo.28.4.046005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 03/24/2023] [Indexed: 05/03/2023]
Abstract
Significance In handheld laser speckle contrast imaging (LSCI), motion artifacts (MA) are inevitable. Suppression of MA leads to a valid and objective assessment of tissue perfusion in a wide range of medical applications including dermatology and burns. Our study shines light on the sources of these artifacts, which have not yet been explored. We propose a model based on optical Doppler effect to predict speckle contrast drop as an indication of MA. Aim We aim to theoretically model MA when an LSCI system measuring on static scattering media is subject to translational displacements. We validate the model using both simulation and experiments. This is the crucial first step toward creating robustness against MA. Approach Our model calculates optical Doppler shifts in order to predict intensity correlation function and contrast of the time-integrated intensity as functions of applied speed based on illumination and detection wavevectors. To validate the theoretical predictions, computer simulation of the dynamic speckles has been carried out. Then experiments are performed by both high-speed and low-framerate imaging. The employed samples for the experiments are a highly scattering matte surface and a Delrin plate of finite scattering level in which volume scattering occurs. Results An agreement has been found between theoretical prediction, simulation, and experimental results of both intensity correlation functions and speckle contrast. Coefficients in the proposed model have been linked to the physical parameters according to the experimental setups. Conclusions The proposed model provides a quantitative description of the influence of the types of illumination and media in the creation of MA. The accurate prediction of MA caused by translation based on Doppler shifts makes our model suitable to study the influence of rotation. Also the model can be extended for the case of dynamic media, such as live tissue.
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Affiliation(s)
- Ata Chizari
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
- Address all correspondence to Ata Chizari,
| | - Wilson Tsong
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Tom Knop
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
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Singh A, Nanda C, Mishra M, Mehta Y. What flow is this! Ann Card Anaesth 2023; 26:204-205. [PMID: 37706387 PMCID: PMC10284480 DOI: 10.4103/aca.aca_23_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 07/12/2021] [Indexed: 09/15/2023] Open
Affiliation(s)
- Ajmer Singh
- Department of Cardiac Anaesthesia, Medanta, The Medicity, Gurugram, Haryana, India
| | - Chinmaya Nanda
- Department of Cardiac Anaesthesia, Medanta, The Medicity, Gurugram, Haryana, India
| | - Manisha Mishra
- Department of Cardiac Anaesthesia, Medanta, The Medicity, Gurugram, Haryana, India
| | - Yatin Mehta
- Department of Cardiac Anaesthesia, Medanta, The Medicity, Gurugram, Haryana, India
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Tang Y, Xu F, Lei P, Li G, Tan Z. Spectral analysis of laser speckle contrast imaging and infrared thermography to assess skin microvascular reactive hyperemia. Skin Res Technol 2023; 29:e13308. [PMID: 37113098 PMCID: PMC10234160 DOI: 10.1111/srt.13308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 02/25/2023] [Indexed: 04/29/2023]
Abstract
BACKGROUND Post-occlusive reactive hyperemia (PORH) test with signal spectral analysis coupled provides potential indicators for the assessment of microvascular functions. OBJECTIVE The objective of this study is to investigate the variations of skin blood flow and temperature spectra in the PORH test. Furthermore, to quantify the oscillation amplitude response to occlusion within different frequency ranges. MATERIALS AND METHODS Ten healthy volunteers participated in the PORH test and their hand skin temperature and blood flow images were captured by infrared thermography (IRT) and laser speckle contrast imaging (LSCI) system, respectively. Extracted signals from selected areas were then transformed into the time-frequency space by continuous wavelet transform for cross-correlation analysis and oscillation amplitude response comparisons. RESULTS The LSCI and IRT signals extracted from fingertips showed stronger hyperemia response and larger oscillation amplitude compared with other areas, and their spectral cross-correlations decreased with frequency. According to statistical analysis, their oscillation amplitudes in the PORH stage were obviously larger than the baseline stage within endothelial, neurogenic, and myogenic frequency ranges (p < 0.05), and their quantitative indicators of oscillation amplitude response had high linear correlations within endothelial and neurogenic frequency ranges. CONCLUSION Comparisons of IRT and LSCI techniques in recording the reaction to the PORH test were made in both temporal and spectral domains. The larger oscillation amplitudes suggested enhanced endothelial, neurogenic, and myogenic activities in the PORH test. We hope this study is also significant for investigations of response to the PORH test by other non-invasive techniques.
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Affiliation(s)
- Yuanliang Tang
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Fei Xu
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Peng Lei
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Guixiang Li
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Zhongwei Tan
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
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Simpson LL, Hansen AB, Moralez G, Amin SB, Hofstaetter F, Gasho C, Stembridge M, Dawkins TG, Tymko MM, Ainslie PN, Lawley JS, Hearon CM. Adrenergic control of skeletal muscle blood flow during chronic hypoxia in healthy males. Am J Physiol Regul Integr Comp Physiol 2023; 324:R457-R469. [PMID: 36717165 PMCID: PMC10026988 DOI: 10.1152/ajpregu.00230.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 01/24/2023] [Accepted: 01/24/2023] [Indexed: 02/01/2023]
Abstract
Sympathetic transduction is reduced following chronic high-altitude (HA) exposure; however, vascular α-adrenergic signaling, the primary mechanism mediating sympathetic vasoconstriction at sea level (SL), has not been examined at HA. In nine male lowlanders, we measured forearm blood flow (Doppler ultrasound) and calculated changes in vascular conductance (ΔFVC) during 1) incremental intra-arterial infusion of phenylephrine to assess α1-adrenergic receptor responsiveness and 2) combined intra-arterial infusion of β-adrenergic and α-adrenergic antagonists propranolol and phentolamine (α-β-blockade) to assess adrenergic vascular restraint at rest and during exercise-induced sympathoexcitation (cycling; 60% peak power). Experiments were performed near SL (344 m) and after 3 wk at HA (4,383 m). HA abolished the vasoconstrictor response to low-dose phenylephrine (ΔFVC: SL: -34 ± 15%, vs. HA; +3 ± 18%; P < 0.0001) and markedly attenuated the response to medium (ΔFVC: SL: -45 ± 18% vs. HA: -28 ± 11%; P = 0.009) and high (ΔFVC: SL: -47 ± 20%, vs. HA: -35 ± 20%; P = 0.041) doses. Blockade of β-adrenergic receptors alone had no effect on resting FVC (P = 0.500) and combined α-β-blockade induced a similar vasodilatory response at SL and HA (P = 0.580). Forearm vasoconstriction during cycling was not different at SL and HA (P = 0.999). Interestingly, cycling-induced forearm vasoconstriction was attenuated by α-β-blockade at SL (ΔFVC: Control: -27 ± 128 vs. α-β-blockade: +19 ± 23%; P = 0.0004), but unaffected at HA (ΔFVC: Control: -20 ± 22 vs. α-β-blockade: -23 ± 11%; P = 0.999). Our results indicate that in healthy males, altitude acclimatization attenuates α1-adrenergic receptor responsiveness; however, resting α-adrenergic restraint remains intact, due to concurrent resting sympathoexcitation. Furthermore, forearm vasoconstrictor responses to cycling are preserved, although the contribution of adrenergic receptors is diminished, indicating a reliance on alternative vasoconstrictor mechanisms.
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Affiliation(s)
- Lydia L Simpson
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Alexander B Hansen
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Gilbert Moralez
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Sachin B Amin
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Florian Hofstaetter
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Christopher Gasho
- Department of Medicine, Division of Pulmonary and Critical Care, Loma Linda University, Loma Linda, California, United States
| | - Mike Stembridge
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, United Kingdom
| | - Tony G Dawkins
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Michael M Tymko
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
- Faculty of Kinesiology, Sport, and Recreation, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Philip N Ainslie
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Justin S Lawley
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Christopher M Hearon
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Dallas, Dallas, Texas, United States
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Sullender CT, Santorelli A, Richards LM, Mannava PK, Smith C, Dunn AK. Using pressure-driven flow systems to evaluate laser speckle contrast imaging. J Biomed Opt 2023; 28:036003. [PMID: 36915371 PMCID: PMC10007838 DOI: 10.1117/1.jbo.28.3.036003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
SIGNIFICANCE Microfluidic flow phantom studies are commonly used for characterizing the performance of laser speckle contrast imaging (LSCI) instruments. The selection of the flow control system is critical for the reliable generation of flow during testing. The majority of recent LSCI studies using microfluidics used syringe pumps for flow control. AIM We quantified the uncertainty in flow generation for a syringe pump and a pressure-regulated flow system. We then assessed the performance of both LSCI and multi-exposure speckle imaging (MESI) using the pressure-regulated flow system across a range of flow speeds. APPROACH The syringe pump and pressure-regulated flow systems were evaluated during stepped flow profile experiments in a microfluidic device using an inline flow sensor. The uncertainty associated with each flow system was calculated and used to determine the reliability for instrument testing. The pressure-regulated flow system was then used to characterize the relative performance of LSCI and MESI during stepped flow profile experiments while using the inline flow sensor as reference. RESULTS The pressure-regulated flow system produced much more stable and reproducible flow outputs compared to the syringe pump. The expanded uncertainty for the syringe pump was 8 to 20 × higher than that of the pressure-regulated flow system across the tested flow speeds. Using the pressure-regulated flow system, MESI outperformed single-exposure LSCI at all flow speeds and closely mirrored the flow sensor measurements, with average errors of 4.6 % ± 2.6 % and 15.7 % ± 4.6 % , respectively. CONCLUSIONS Pressure-regulated flow systems should be used instead of syringe pumps when assessing the performance of flow measurement techniques with microfluidic studies. MESI offers more accurate relative flow measurements than traditional LSCI across a wide range of flow speeds.
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Affiliation(s)
- Colin T. Sullender
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Adam Santorelli
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Lisa M. Richards
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Pawan K. Mannava
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Christopher Smith
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Andrew K. Dunn
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
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Karabulut M, Bitting M, Bejar J. Postexercise Arterial Compliance and Hemodynamic Responses to Various Durations and Intensities of Aerobic Exercise. J Strength Cond Res 2023; 37:589-596. [PMID: 36730586 DOI: 10.1519/jsc.0000000000004321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
ABSTRACT Karabulut, M, Bitting, M, and Bejar, J. Postexercise arterial compliance and hemodynamic responses to various durations and intensities of aerobic exercise. J Strength Cond Res 37(3): 589-596, 2023-The purpose of this study was to determine the effects of various aerobic training protocols using different intensities and durations on arterial compliance and hemodynamic responses. Seventeen male subjects (age = 23.1 ± 2.8 years) performed a maximal oxygen consumption (V̇ o2 max) test, followed by 3 randomly assigned exercise test sessions, each on a separate day. At the beginning of each test session, pre-exercise baseline assessments of arterial elasticity, hemodynamic variables, and pulse wave velocity (PWV) were performed after a 10-minute rest. After baseline measurements, participants performed either a bout of aerobic exercise on a treadmill for 60 minutes at 65% of V̇ o2 max (60min); 20 minutes at 40% of V̇ o2 max (20min); or for 20 minutes at 40% of V̇ o2 max with blood flow restriction (BFR; 20min-BFR). All baseline measurements were repeated at the completion of each testing session. Significance for this study was set at p ≤ 0.05. The 60min session resulted in significant increases in small artery elasticity (SAE) compared with the 20min-BFR session ( p < 0.03) and decreases in both systemic vascular resistance (SVR) and total vascular impedance (TVI) compared with both 20min sessions ( p < 0.01). The carotid to radial PWV was significantly lower after both the 60min and the 20min-BFR sessions compared with the 20min session ( p < 0.02). The findings indicate that the duration and the intensity of exercise are important factors for improving SAE, SVR, and TVI. In addition, 20min-BFR at 40% V̇ o2 max may result in site-specific modifications in PWV that is comparable with those seen after 60 minutes of exercise at 65% V̇ o2 max.
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Affiliation(s)
- Murat Karabulut
- Department of Health and Human Performance, University of Texas Rio Grande Valley, Brownsville, Texas
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Chaseling GK, Debray A, Gravel H, Ravanelli N, Bartlett A, Gagnon D. The acute effect of heat exposure on forearm macro- and microvascular function: Impact of measurement timing, heating modality and biological sex. Exp Physiol 2023; 108:221-239. [PMID: 36533971 PMCID: PMC10103856 DOI: 10.1113/ep090732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/30/2022] [Indexed: 12/23/2022]
Abstract
NEW FINDINGS What is the central question of this study? Do measurement timing, heating modality and biological sex modulate the acute effect of heat exposure on brachial artery flow-mediated dilatation and postocclusion reactive hyperaemia? What is the main finding and its importance? The acute effect of heat exposure on brachial artery flow-mediated dilatation and postocclusion reactive hyperaemia is: (1) transient and short lasting; (2) different between forearm and whole-body heating; (3) unaffected by forearm heating during whole-body heating; and (4) not different but not always equivalent between males and females. These findings provide a useful basis for future studies to investigate the acute effect of heat exposure on vascular function. ABSTRACT The aim of this study was to gain a better understanding of the acute effect of heat exposure on brachial artery flow-mediated dilatation (FMD) and postocclusion reactive hyperaemia (PORH) by: characterizing the time course of changes post-heating; comparing forearm and whole-body heating; determining the impact of forearm heating during whole-body heating; and comparing males and females. Twenty adults (11 males and nine females; 28 ± 6 years of age) underwent two forearm [10 min electric blanket (EB) or 30 min hot water immersion (WI)] and two whole-body [60 min water-perfused suit with forearm covered (WBH-C) or uncovered (WBH-U)] heating modalities. The FMD and PORH were measured before and after (≤5, 30, 60, 90 and 120 min) heating. The FMD increased from baseline 30 min after EB, and 30 and 90 min after WI. In contrast, FMD decreased from baseline immediately after both WBH modalities. Peak PORH increased immediately after WI and both WBH modalities. Total PORH did not differ after WI, whereas it decreased immediately after both WBH modalities. Covering the forearm during WBH did not alter acute changes in FMD or PORH. Changes in FMD and PORH did not differ statistically between males and females during each heating modality, although the observed differences could not always be considered equivalent. These results demonstrate that the acute effect of heat exposure on brachial artery FMD and PORH is: (1) transient and short lasting; (2) different between forearm heating and WBH; (3) unaffected by direct forearm heating during WBH; and (4) not different but not always equivalent between males and females.
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Affiliation(s)
- Georgia K. Chaseling
- Montreal Heart InstituteMontréalQuébecCanada
- Department of Pharmacology and PhysiologyFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
| | - Amélie Debray
- Montreal Heart InstituteMontréalQuébecCanada
- Department of MedicineFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
| | - Hugo Gravel
- School of Kinesiology and Exercise ScienceFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
| | | | - Audrey‐Ann Bartlett
- Montreal Heart InstituteMontréalQuébecCanada
- School of Kinesiology and Exercise ScienceFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
| | - Daniel Gagnon
- Montreal Heart InstituteMontréalQuébecCanada
- Department of Pharmacology and PhysiologyFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
- School of Kinesiology and Exercise ScienceFaculty of MedicineUniversité de MontréalMontréalQuébecCanada
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Kambic T, Jug B, Piepoli MF, Lainscak M. Is blood flow restriction resistance training the missing piece in cardiac rehabilitation of frail patients? Eur J Prev Cardiol 2023; 30:117-122. [PMID: 35253869 DOI: 10.1093/eurjpc/zwac048] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 01/27/2023]
Affiliation(s)
- Tim Kambic
- Cardiac Rehabilitation Unit and Department of Research and Education, General Hospital Murska Sobota, Rakican, Ulica dr. Vrbnjaka 6, Murska Sobota 9000, Slovenia
| | - Borut Jug
- Department of Vascular Diseases, University Medical Centre Ljubljana, Zaloška 7, Ljubljana 1000, Slovenia
- Faculty of Medicine, University of Ljubljana, Zaloška 7, Ljubljana 1000, Slovenia
| | - Massimo Francesco Piepoli
- Heart Failure Unit, G. da Saliceto Hospital, AUSL Piacenza, Via Taverna Giuseppe 49, Piacenza 29121, Italy
- Institute of Life Sciences, Sant'Anna School of Advanced Studies, Via Santa Cecilia 3, Pisa 56127, Italy
| | - Mitja Lainscak
- Faculty of Medicine, University of Ljubljana, Zaloška 7, Ljubljana 1000, Slovenia
- Division of Cardiology, Department of Internal Medicine, General Hospital Murska Sobota, Rakican, Ulica dr. Vrbnjaka 6, Murska Sobota 9000, Slovenia
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Kaga T, Kato H, Imai T, Ando T, Noda Y, Miura T, Enomoto Y, Hyodo F, Iwama T, Matsuo M. Non-invasive regional cerebral blood flow quantification in the 123I-IMP autoradiography using artificial neural network. PLoS One 2023; 18:e0281958. [PMID: 36888603 PMCID: PMC9994717 DOI: 10.1371/journal.pone.0281958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 02/04/2023] [Indexed: 03/09/2023] Open
Abstract
PURPOSE Regional cerebral blood flow (rCBF) quantification using 123I-N-isopropyl-p-iodoamphetamine (123I-IMP) requires an invasive, one-time-only arterial blood sampling for measuring the 123I-IMP arterial blood radioactivity concentration (Ca10). The purpose of this study was to estimate Ca10 by machine learning (ML) using artificial neural network (ANN) regression analysis and consequently calculating rCBF and cerebral vascular reactivity (CVR) in the dual-table autoradiography (DTARG) method. MATERIALS AND METHODS This retrospective study included 294 patients who underwent rCBF measurements through the 123I-IMP DTARG. In the ML, the objective variable was defined by the measured Ca10, whereas the explanatory variables included 28 numeric parameters, such as patient characteristic values, total injection 123I-IMP radiation dose, cross-calibration factor, and the distribution of 123I-IMP count in the first scan. ML was performed with training (n = 235) and testing (n = 59) sets. Ca10 was estimated in testing set by our proposing model. Alternatively, the estimated Ca10 was also calculated via the conventional method. Subsequently, rCBF and CVR were calculated using estimated Ca10. Pearson's correlation coefficient (r-value) for the goodness of fit and the Bland-Altman analysis for assessing the potential agreement and bias were performed between the measured and estimated values. RESULTS The r-value of Ca10 estimated by our proposed model was higher compared with the conventional method (0.81 and 0.66, respectively). In the Bland-Altman analysis, mean differences of 4.7 (95% limits of agreement (LoA): -18-27) and 4.1 (95% LoA: -35-43) were observed using proposed model and the conventional method, respectively. The r-values of rCBF at rest, rCBF after the acetazolamide challenge, and CVR calculated using the Ca10 estimated by our proposed model were 0.83, 0.80 and 0.95, respectively. CONCLUSION Our proposed ANN-based model could accurately estimate the Ca10, rCBF, and CVR in DTARG. These results would enable non-invasive rCBF quantification in DTARG.
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Affiliation(s)
- Tetsuro Kaga
- Department of Radiology, Gifu University, Gifu, Japan
- * E-mail:
| | - Hiroki Kato
- Department of Radiology, Gifu University, Gifu, Japan
| | - Toyohiro Imai
- Department of Radiology Services, Gifu University Hospital, Gifu, Japan
| | - Tomohiro Ando
- Department of Radiology, Gifu University, Gifu, Japan
| | | | - Takayuki Miura
- Department of Radiology Services, Gifu University Hospital, Gifu, Japan
| | - Yukiko Enomoto
- Department of Neurosurgery, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Fuminori Hyodo
- Department of Radiology, Frontier Science for Imaging, Gifu University, Gifu, Japan
| | - Toru Iwama
- Department of Neurosurgery, Gifu University Graduate School of Medicine, Gifu, Japan
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