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Felipe RA, Plescia M, Peterman E, Tomlin H, Sells M, Easley C, Ahmed K, Presley-Cantrell L. A Public Health Framework to Improve Population Health Through Health Care and Community Clinical Linkages: The ASTHO/CDC Heart Disease and Stroke Prevention Learning Collaborative. Prev Chronic Dis 2019; 16:E124. [PMID: 31517600 PMCID: PMC6745896 DOI: 10.5888/pcd16.190065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Thirty-one state and territorial public health agencies participated in a learning collaborative to improve diagnosis and management of hypertension in clinical and community settings. These health agencies implemented public health and clinical interventions in medical settings and health organizations using a logic model and rapid quality improvement process focused on a framework of 4 systems-change levers: 1) data-driven action, 2) clinical practice standardization, 3) clinical-community linkages, and 4) financing and policy. We provide examples of how public health agencies applied the systems-change framework in all 4 areas to assess and modify population-based interventions to improve control of hypertension. This learning collaborative approach illustrates the importance of public health in the prevention and control of chronic disease by supporting interventions that address community and clinical linkages to address medical risk factors associated with cardiovascular disease.
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Affiliation(s)
- Rose Anne Felipe
- Association of State and Territorial Health Officials, 2231 Crystal Dr, Suite 450, Arlington, VA 22202.
| | - Marcus Plescia
- Association of State and Territorial Health Officials, Arlington, Virginia
| | - Emily Peterman
- Association of State and Territorial Health Officials, Arlington, Virginia
| | - Holly Tomlin
- Tomlin Health Sciences Communications, Brooklyn, New York
| | - Michael Sells
- Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Camillia Easley
- Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Kaha Ahmed
- Centers for Disease Control and Prevention, Atlanta, Georgia
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Hain D, Tomlin H, Gibson C. Administration of Etelcalcetide for the Treatment of Secondary Hyperparathyroidism in Patients with CKD-MBD on Hemodialysis: A Nephrology Nursing Perspective. Nephrol Nurs J 2019; 46:315-290. [PMID: 31199098] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The number, volume, and timing of oral medications prescribed to treat secondary hyperparathyroidism can add to the burden of disease management for both the patient and the nurse. Administering intravenous (IV) medication when possible has the potential of reducing the burden of medication management. Data on the use of IV calcimimetic etelcalcetide has shown improvement in blood calcium, phosphorus, and parathyroid hormone levels. IV administration of etelcalcetide at the end of each hemodialysis session may reduce the pill burden for patients and has the potential to help improve disease management within an environment that supports person-centered care.
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Affiliation(s)
- Debra Hain
- Professor, MSN Coordinator: AGNP Concentration, Florida Atlantic University, Christine E Lynn College of Nursing, Boca Raton, FL
- Nurse Practitioner, Cleveland Clinic Florida, Department of Nephrology, Weston, FL
- President-Elect of ANNA's South Florida Flamingo Chapter
| | | | - Cristian Gibson
- Senior Regional Medical Liaison, Amgen Inc., Thousand Oaks, CA
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Wolf M, Block GA, Chertow GM, Cooper K, Fouqueray B, Moe SM, Sun Y, Tomlin H, Vervloet M, Oberbauer R. Effects of etelcalcetide on fibroblast growth factor 23 in patients with secondary hyperparathyroidism receiving hemodialysis. Clin Kidney J 2019; 13:75-84. [PMID: 32082556 PMCID: PMC7025329 DOI: 10.1093/ckj/sfz034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 03/11/2019] [Indexed: 12/11/2022] Open
Abstract
Background Etelcalcetide is an intravenous calcimimetic approved for treatment of secondary hyperparathyroidism (sHPT) in patients receiving hemodialysis. Besides lowering parathyroid hormone (PTH), etelcalcetide also significantly reduces fibroblast growth factor 23 (FGF23), but the mechanisms are unknown. Methods To investigate potential mediators of etelcalcetide-induced FGF23 reduction, we performed secondary analyses of the 26-week randomized trials that compared the effects on PTH of etelcalcetide (n = 509) versus placebo (n = 514) and etelcalcetide (n = 340) versus cinacalcet (n = 343) in adults with sHPT receiving hemodialysis. We analyzed changes in FGF23 in relation to changes in PTH, calcium, phosphate and bone turnover markers. We also investigated how concomitant treatments aimed at mitigating hypocalcemia altered the FGF23-lowering effects of etelcalcetide. Results Etelcalcetide reduced FGF23 [median % change (quartile 1–quartile 3)] from baseline to the end of the trial significantly more than placebo [–56% (–85 to –7) versus +2% (–40 to +65); P < 0.001] and cinacalcet [–68% (–87 to –26) versus –41% (–76 to +25); P < 0.001]. Reductions in FGF23 correlated strongly with reductions in calcium and phosphate, but not with PTH; correlations with bone turnover markers were inconsistent and of borderline significance. Increases in concomitant vitamin D administration partially attenuated the FGF23-lowering effect of etelcalcetide, but increased dialysate calcium concentration versus no increase and increased dose of calcium supplementation versus no increase did not attenuate the FGF23-lowering effects of etelcalcetide. Conclusion These data suggest that etelcalcetide potently lowers FGF23 in patients with sHPT receiving hemodialysis and that the effect remains detectable among patients who receive concomitant treatments aimed at mitigating treatment-associated decreases in serum calcium.
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Affiliation(s)
- Myles Wolf
- Department of Medicine, Division of Nephrology, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA
| | | | - Glenn M Chertow
- Department of Medicine, Division of Nephrology, Stanford University School of Medicine, Palo Alto, CA, USA
| | | | | | - Sharon M Moe
- Department of Medicine, Division of Nephrology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yan Sun
- Amgen, Inc., Thousand Oaks, CA, USA
| | | | - Marc Vervloet
- Department of Nephrology, VU University Medical Center, Amsterdam, The Netherlands
| | - Rainer Oberbauer
- Department of Nephrology, Medical University of Vienna, Vienna, Austria
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Ho Tiu C, Asfour L, Jakab M, Tomlin H, Griffiths C, Young H. An art‐based visual literacy training course to enhance clinical skills in dermatology trainees. J Eur Acad Dermatol Venereol 2019; 33:e310-e312. [DOI: 10.1111/jdv.15588] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- C.P.S.P. Ho Tiu
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
| | - L. Asfour
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
| | - M. Jakab
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
| | - H. Tomlin
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
| | - C.E.M. Griffiths
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
| | - H.S. Young
- Centre for Dermatology Research Manchester Academic Health Science Centre Salford Royal NHS Foundation Trust The University of Manchester Manchester UK
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Block GA, Chertow GM, Sullivan JT, Deng H, Mather O, Tomlin H, Serenko M. An integrated analysis of safety and tolerability of etelcalcetide in patients receiving hemodialysis with secondary hyperparathyroidism. PLoS One 2019; 14:e0213774. [PMID: 30875390 PMCID: PMC6420005 DOI: 10.1371/journal.pone.0213774] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 02/11/2019] [Indexed: 01/13/2023] Open
Abstract
Background Calcimimetics have been shown to be effective and safe therapies for the treatment of secondary hyperparathyroidism (sHPT), a serious complication of disordered mineral metabolism associated with dialysis-dependent chronic kidney disease. Etelcalcetide, a recently approved intravenous calcimimetic, reduces serum parathyroid hormone (PTH), calcium, phosphorus, and fibroblast growth factor-23 concentrations. Here we report the first integrated safety profile of etelcalcetide using pooled data from five pivotal clinical trials. Methods This analysis included data from patients receiving hemodialysis with moderate to severe sHPT enrolled in two randomized, placebo-controlled trials; a randomized active-controlled (with cinacalcet) trial; and two single-arm, open-label extension trials. Patients initially received etelcalcetide intravenously 5 mg three times weekly (TIW) after hemodialysis; with potential dose increases of 2.5 or 5 mg at 4-week intervals to a maximum dose of 15 mg TIW, depending on serum PTH and calcium levels. The nature, frequency, and severity of treatment-emergent adverse events (AEs) and changes in laboratory parameters were assessed. Results Overall, we evaluated 1023 patients from the placebo-controlled trials, 683 from the active-controlled trial, and 1299 from open-label extensions. The frequency and nature of common treatment-emergent AEs reported for the etelcalcetide arm were consistent among the placebo-controlled and active-controlled trials. The most common AEs were those related to mineral metabolism (decreased blood calcium, hypophosphatemia, muscle spasms) or gastrointestinal abnormalities (diarrhea, nausea, vomiting). Hypocalcemia leading to discontinuation of either calcimimetic was experienced in ≤ 1% of patients. Conclusions This integrated safety assessment of etelcalcetide across placebo- and active-controlled trials showed an overall favorable risk/benefit profile, with safety similar to that of cinacalcet. Consistent with its mechanism of action, the most important risks associated with etelcalcetide were serum calcium reductions and hypocalcemia-related AEs; no new safety findings were identified in the pooled long-term extension trials.
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Affiliation(s)
| | - Glenn M. Chertow
- Stanford University, Stanford, California, United States of America
| | | | - Hongjie Deng
- Amgen Inc., Thousand Oaks, California, United States of America
| | - Omar Mather
- Amgen Inc., Thousand Oaks, California, United States of America
- * E-mail:
| | - Holly Tomlin
- Amgen Inc., Thousand Oaks, California, United States of America
| | - Michael Serenko
- Amgen Inc., Thousand Oaks, California, United States of America
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Vervloet M, Cooper K, Block G, Chertow G, Fouqueray B, Moe S, Sun Y, Tomlin H, Wolf M, Oberbauer R. FP378BASELINE LEVELS OF FGF23 AND EFFECTS OF ETELCALCETIDE. Nephrol Dial Transplant 2018. [DOI: 10.1093/ndt/gfy104.fp378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- M Vervloet
- Nephrology, VU University Medical Center, Amsterdam, Netherlands
| | - K Cooper
- Global Medical, Amgen Inc, Thousand Oaks, CA, United States
| | - G Block
- Nephrology, Denver Nephrology, Denver, CO, United States
| | - G Chertow
- Nephrology, Stanford University, Stanford, CA, United States
| | | | - S Moe
- Nephrology, Indiana University, Indianapolis, IN, United States
| | - Y Sun
- Biostatistics, Amgen Inc, Thousand Oaks, CA, United States
| | - H Tomlin
- Global Medical, Amgen Inc, Thousand Oaks, CA, United States
| | - M Wolf
- Nephrology, Duke University, Durham, NC, United States
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Affiliation(s)
- L.L. Griffin
- Dermatology Centre; Salford Royal NHS Foundation Trust; University of Manchester; Manchester Academic Health Science Centre; Manchester U.K
| | - N.Y.Z. Chiang
- Dermatology Centre; Salford Royal NHS Foundation Trust; University of Manchester; Manchester Academic Health Science Centre; Manchester U.K
| | - H. Tomlin
- Dermatology Centre; Salford Royal NHS Foundation Trust; University of Manchester; Manchester Academic Health Science Centre; Manchester U.K
| | - H.S. Young
- Dermatology Centre; Salford Royal NHS Foundation Trust; University of Manchester; Manchester Academic Health Science Centre; Manchester U.K
| | - C.E.M. Griffiths
- Dermatology Centre; Salford Royal NHS Foundation Trust; University of Manchester; Manchester Academic Health Science Centre; Manchester U.K
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Wolf M, Block G, Chertow G, Cooper K, Fouqueray B, Moe S, Sun Y, Tomlin H, Vervloet M, Oberbauer R. SO033IMPACT OF ETELCALCETIDE ON FGF23 LEVELS DURING THE TREATMENT OF SECONDARY HYPERPARATHYROIDISM IN PATIENTS ON HEMODIALYSIS. Nephrol Dial Transplant 2017. [DOI: 10.1093/ndt/gfx105.so033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Cooper K, Quarles D, Kubo Y, Tomlin H, Goodman W. Relationship between Reductions in Parathyroid Hormone and Serum Phosphorus during the Management of Secondary Hyperparathyroidism with Calcimimetics in Hemodialysis Patients. Nephron Clin Pract 2012. [DOI: 10.1159/000345164] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Behets F, Mutombo GM, Edmonds A, Dulli L, Belting MT, Kapinga M, Pantazis A, Tomlin H, Okitolonda E. Reducing vertical HIV transmission in Kinshasa, Democratic Republic of Congo: trends in HIV prevalence and service delivery. AIDS Care 2009; 21:583-90. [PMID: 19444666 DOI: 10.1080/09540120802385595] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Scale-up of vertical HIV transmission prevention has been too slow in sub-Saharan Africa. We describe approaches, challenges, and results obtained in Kinshasa. Staff members of 21 clinics managed by public servants or non-governmental organizations were trained in improved basic antenatal care (ANC) including nevirapine (NVP)-based HIV transmission prevention. Program initiation was supported on-site logistically and technically. Aggregate implementation data were collected and used for program monitoring. Contextual information was obtained through a survey. Among 45,262 women seeking ANC from June 2003 through July 2005, 90% accepted testing; 792 (1.9%) had HIV of whom 599 (76%) returned for their result. Among 414 HIV+ women who delivered in participating maternities, NVP coverage was 79%; 92% of newborns received NVP. Differences were noted by clinic management in program implementation and HIV prevalence (1.2 to 3.0%). Initiating vertical HIV transmission prevention embedded in improved antenatal services in a fragile, fragmented, severely resource-deprived health care system was possible and improved over time. Scope and quality of service coverage should further increase; strategies to decrease loss to follow-up of HIV+ women should be identified to improve program effectiveness. The observed differences in HIV prevalence highlight the importance of selecting representative sentinel surveillance centers.
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Affiliation(s)
- Frieda Behets
- Epidemiology, University of North Carolina at Chapel Hill, NC, USA.
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Alper AB, Tomlin H, Sadhwani U, Whelton A, Puschett J. Effects of the selective cyclooxygenase-2 inhibitor analgesic celecoxib on renal carbonic anhydrase enzyme activity: a randomized, controlled trial. Am J Ther 2006; 13:229-35. [PMID: 16772765 DOI: 10.1097/01.mjt.0000182359.63457.01] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Rofecoxib and celecoxib were the first cyclooxygenase-2 (COX-2)-specific inhibitors to be marketed as effective anti inflammatory agents. The results of several recent trials and a meta analysis of currently available studies all demonstrate a greater incidence of increased blood pressure, edema, and cardiovascular events in subjects treated with rofecoxib compared with celecoxib. As an approach to the assessment of molecular mechanisms that may contribute to these cardiorenal differences, this study investigated the inhibitory effects of celecoxib on renal carbonic anhydrase enzyme activity in human hypertensive subjects because in vitro enzyme studies demonstrate such an effect. Ten subjects with stable, treated hypertension were randomized to 1 of 3 treatment sequences, which included, in differing order, 200 mg celecoxib twice a day, 250 mg acetazolamide twice a day, or placebo twice a day. Whereas acetazolamide caused a bicarbonate diuresis and a hyperchloremic metabolic acidosis, celecoxib appeared to have no detectable effect on renal carbonic anhydrase or acid-base homeostasis. Thus, in this short-term study of human subjects, therapeutic doses of celecoxib did not appear to have a clinically significant inhibitory action on renal carbonic anhydrase.
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Affiliation(s)
- Arnold B Alper
- Department of Medicine, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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Vasterling JJ, Duke LM, Tomlin H, Lowery N, Kaplan E. Global-local visual processing in posttraumatic stress disorder. J Int Neuropsychol Soc 2004; 10:709-18. [PMID: 15327718 DOI: 10.1017/s1355617704105031] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2003] [Revised: 03/08/2004] [Indexed: 11/07/2022]
Abstract
The purpose of this study was to examine a behavioral index of hemispheric asymmetry (i.e., visual hierarchical attention) in posttraumatic stress disorder (PTSD), a disorder characterized by anxiety and other emotional symptoms. A reaction time based, computerized, global-local visual paradigm was administered to 26 PTSD-diagnosed and 22 psychopathology-free right-handed, male Vietnam War zone veterans. Results indicated that PTSD-diagnosed veterans displayed slower reaction times to all targets than the no-mental disorders comparison sample. However, findings also revealed a Group x Target location interaction in which the PTSD group was slower than the no-disorders comparison sample to respond to local, but not global, targets. Moreover, relative global bias was greater among PTSD-diagnosed veterans than their no-diagnosis counterparts. Findings provide partial support for the hypothesis that PTSD may be associated with a functional cerebral asymmetry favoring the right hemisphere.
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Cerbone A, Sautter FJ, Manguno-Mire G, Evans WE, Tomlin H, Schwartz B, Myers L. Differences in smooth pursuit eye movement between posttraumatic stress disorder with secondary psychotic symptoms and schizophrenia. Schizophr Res 2003; 63:59-62. [PMID: 12892858 DOI: 10.1016/s0920-9964(02)00341-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Studies show high comorbidity between post-traumatic stress disorder and psychotic symptoms. Despite this fact, there has been only one published study of the neurobiology of this enigmatic disorder. This preliminary study examines the relationship between psychotic symptoms in post-traumatic stress disorder (PTSD) and schizophrenia by measuring smooth pursuit eye movement (SPEM) in subjects with PTSD and secondary psychotic symptoms, schizophrenia, and healthy controls. The results show that PTSD with secondary psychotic symptoms is associated with a SPEM deficit that is different from the SPEM deficit associated with schizophrenia.
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Affiliation(s)
- Arleen Cerbone
- Department of Psychology, Tulane University, 6823 St. Charles Avenue, New Orleans, LA 70112, USA
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Vasterling JJ, Brailey K, Tomlin H, Rice J, Sutker PB. Olfactory functioning in Gulf War-era veterans: relationships to war-zone duty, self-reported hazards exposures, and psychological distress. J Int Neuropsychol Soc 2003; 9:407-18. [PMID: 12666765 DOI: 10.1017/s1355617703930062] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Revised: 05/13/2002] [Indexed: 11/08/2022]
Abstract
To explore possible neurotoxic sequelae of Gulf War (GW) participation, olfactory identification performance, neurocognitive functioning, health perceptions, and emotional distress were assessed in 72 veterans deployed to the GW and 33 military personnel activated during the GW but not deployed to the war zone. Findings revealed that war-zone-exposed veterans reported more concerns about health, cognitive functioning, and depression than did their counterparts who did not see war-zone duty. There was no evidence that performances on olfactory or neurocognitive measures were related to war-zone duty or to self-reported exposure to GW toxicants. However, symptoms of emotional distress were positively correlated with self-report of health and cognitive complaints. Results do not provide support for the hypothesis that objectively-measured sensory (i.e., olfactory) or cognitive deficits are related to war-zone participation but do underscore the increasingly demonstrated association between self-reported health concerns and symptoms of emotional distress.
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Affiliation(s)
- Jennifer J Vasterling
- Mental Health Service Line, Veterans Affairs Medical Center, New Orleans, Louisiana 70112, USA.
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Boehm EA, Radda GK, Tomlin H, Clark JF. The utilisation of creatine and its analogues by cytosolic and mitochondrial creatine kinase. Biochim Biophys Acta 1996; 1274:119-28. [PMID: 8664304 DOI: 10.1016/0005-2728(96)00018-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have investigated the utilisation of four analogues of creatine by cytosolic Creatine Kinase (CK), using 31P-NMR in the porcine carotid artery, and by mitochondrial CK (Mt-CK), using oxygen consumption studies in isolated heart mitochondria and skinned fibers. Porcine carotid arteries were superfused for 12 h with Krebs-Henseleit buffer at 22 degrees C, containing 11 mM glucose as substrate, and supplemented with either 20 mM beta-guanidinopropionic acid (beta-GPA), methyl-guanidinopropionic acid (m-GPA), guanidinoacetic acid (GA) or cyclocreatine (cCr). All four analogues entered the tissue and became phosphorylated by CK as seen by 31 P-NMR, Inhibition of oxidative metabolism by 1 mM cyanide after accumulation of the phosphorylated analogue resulted in the utilisation of PCr, beta-GPA-P, GA-P and GA-P over a similar time course (approximately 2 h), despite very different kinetic properties of these analogues in vitro. cCr-P was utilised at a significantly slower rate, but was rapidly dephosphorylated in the presence of both 1 mM iodoacetate and cyanide (to inhibit both glycolysis and oxidative metabolism respectively). The technique of creatine stimulated respiration was used to investigate the phosphorylation of the analogues by Mt-CK, Isolated mitochondria were subjected to increasing [ATP], whereas skinned fibres received a similar protocol with increasing [ADP]. There was a significant stimulation of respiration by creatine and cCr in isolated mitochondria (decreased K(m) and increased Vmax vs control), but none by GA, mGPA or beta-GPA (also in skinned fibres), indicating that these latter analogues were not utilised by Mt-CK. These results demonstrate differences in the phosphorylation and dephosphorylation of creatine and its analogues by cytosolic CK and Mt-CK in vivo and in vitro.
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Affiliation(s)
- E A Boehm
- Department of Biochemistry, University of Oxford, UK
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Tomlin H, Brancato C, Pistone V, Smith LG, Tischler C, Pundy A. BCG-not for Newark; BCG-for newark. J Med Soc N J 1975; 72:501-8. [PMID: 1055818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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17
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