1
|
Manjit M, Kumar M, Jha A, Bharti K, Kumar K, Tiwari P, Tilak R, Singh V, Koch B, Mishra B. Formulation and characterization of polyvinyl alcohol/chitosan composite nanofiber co-loaded with silver nanoparticle & luliconazole encapsulated poly lactic-co-glycolic acid nanoparticle for treatment of diabetic foot ulcer. Int J Biol Macromol 2024; 258:128978. [PMID: 38145692 DOI: 10.1016/j.ijbiomac.2023.128978] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/30/2023] [Accepted: 12/20/2023] [Indexed: 12/27/2023]
Abstract
Chronic wounds are prone to fungal infections, possess a significant challenge, and result in substantial mortality. Diabetic wounds infected with Candida strains are extremely common. It can create biofilm at the wound site, which can lead to antibiotic resistance. As a result, developing innovative dressing materials that combat fungal infections while also providing wound healing is a viable strategy to treat infected wounds and address the issue of antibiotic resistance. Present work proposed anti-infective dressing material for the treatment of fungal strains Candida-infected diabetic foot ulcer (DFU). The nanofiber was fabricated using polyvinyl Alcohol/chitosan as hydrogel base and co-loaded with silver nanoparticles (AgNP) and luliconazole-nanoparticles (LZNP) nanoparticles, prepared using PLGA. Fabricated nanofibers had pH close to target area and exhibited hydrophilic surface suitable for adhesion to wound area. The nanofibers showed strong antifungal and antibiofilm properties against different strains of Candida; mainly C. albicans, C. auris, C. krusei, C. parapsilosis and C. tropicalis. Nanofibers exhibited excellent water retention potential and water vapour transmission rate. The nanofibers had sufficient payload capacity towards AgNP and LZNP, and provided controlled release of payload, which was also confirmed by in-vivo imaging. In-vitro studies confirmed the biocompatibility and enhanced proliferation of Human keratinocytes cells (HaCaT). In-vivo studies showed accelerated wound closure by providing ant-infective action, supporting cellular proliferation and improving blood flow, all collectively contributing in expedited wound healing.
Collapse
Affiliation(s)
- Manjit Manjit
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| | - Manish Kumar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| | - Abhishek Jha
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| | - Kanchan Bharti
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| | - Krishan Kumar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| | - Punit Tiwari
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Ragini Tilak
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Virendra Singh
- Cancer Biology Laboratory, Department of Zoology Institute of Science, Banaras Hindu University, Varanasi 221005, India.
| | - Biplob Koch
- Cancer Biology Laboratory, Department of Zoology Institute of Science, Banaras Hindu University, Varanasi 221005, India.
| | - Brahmeshwar Mishra
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
| |
Collapse
|
2
|
Ide K, Tokunaga M, Hiratsuka S, Iwasaki T, Nishifuji K. Validation of laser doppler flowmetry to measure dermal blood flow of the pinnae in dogs with pinnal alopecia. Vet Dermatol 2023; 34:70-76. [PMID: 36229967 DOI: 10.1111/vde.13126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 06/23/2022] [Accepted: 07/07/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND Laser Doppler flowmetry (LDF) is a noninvasive method of measuring regional blood flow in humans. However, this method has not been widely applied to measure blood flow in dogs. HYPOTHESIS/OBJECTIVES We hypothesised that LDF can measure changes in blood flow in canine pinnae accurately. The objectives were to determine whether LDF could accurately detect dermal blood flow changes in canine pinnae caused by haemodynamic drugs and characterize the dermal blood flow in dogs with pinnal alopecia. ANIMALS Sixteen laboratory-owned healthy dogs, 25 client-owned healthy control dogs and six dogs with pinnal alopecia suspected to be secondary to ischaemic dermatoses. MATERIALS AND METHODS Clinical doses of the haemodynamic drugs atropine, medetomidine and dibutyryl cyclic adenosine monophosphate (dBcAMP), as well as topical dBcAMP, were administered to healthy beagles. Subsequently, an LDF apparatus was attached to the pinnae to analyse changes in dermal blood flow. Finally, LDF was used to measure auricular dermal blood flow in dogs with pinnal alopecia compared to healthy dogs. RESULTS Dermal blood flow increased after atropine injection, during dBcAMP infusion and after topical dBcAMP ointment application, and decreased after medetomidine injection. Auricular dermal blood flow (in mL/min/100 g tissue) was significantly (p < 0.05) lower in dogs with pinnal alopecia than in healthy dogs. CONCLUSIONS AND CLINICAL RELEVANCE Laser Doppler flowmetry is useful for measuring dermal blood flow in canine pinnae; it can be a noninvasive method to monitor ischaemic conditions of dog skin.
Collapse
Affiliation(s)
- Kaori Ide
- Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan
| | - Makoto Tokunaga
- Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan
| | - Shogo Hiratsuka
- Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan
| | - Toshiroh Iwasaki
- Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan.,Pet Skin Clinic, Kobe, Hyogo, Japan
| | - Koji Nishifuji
- Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan
| |
Collapse
|
3
|
Raia L, Zafrani L. Endothelial Activation and Microcirculatory Disorders in Sepsis. Front Med (Lausanne) 2022; 9:907992. [PMID: 35721048 PMCID: PMC9204048 DOI: 10.3389/fmed.2022.907992] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/16/2022] [Indexed: 11/19/2022] Open
Abstract
The vascular endothelium is crucial for the maintenance of vascular homeostasis. Moreover, in sepsis, endothelial cells can acquire new properties and actively participate in the host's response. If endothelial activation is mostly necessary and efficient in eliminating a pathogen, an exaggerated and maladaptive reaction leads to severe microcirculatory damage. The microcirculatory disorders in sepsis are well known to be associated with poor outcome. Better recognition of microcirculatory alteration is therefore essential to identify patients with the worse outcomes and to guide therapeutic interventions. In this review, we will discuss the main features of endothelial activation and dysfunction in sepsis, its assessment at the bedside, and the main advances in microcirculatory resuscitation.
Collapse
Affiliation(s)
- Lisa Raia
- Medical Intensive Care Unit, Hôpital Saint-Louis, Assistance Publique des Hôpitaux de Paris, Paris, France
| | - Lara Zafrani
- Medical Intensive Care Unit, Hôpital Saint-Louis, Assistance Publique des Hôpitaux de Paris, Paris, France
- INSERM UMR 976, University of Paris Cité, Paris, France
- *Correspondence: Lara Zafrani
| |
Collapse
|
4
|
Methods to evaluate vascular function: a crucial approach towards predictive, preventive, and personalised medicine. EPMA J 2022; 13:209-235. [PMID: 35611340 PMCID: PMC9120812 DOI: 10.1007/s13167-022-00280-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/02/2022] [Indexed: 11/06/2022]
Abstract
Endothelium, the gatekeeper of our blood vessels, is highly heterogeneous and a crucial physical barrier with the ability to produce vasoactive and protective mediators under physiological conditions. It regulates vascular tone, haemostasis, vascular inflammation, remodelling, and angiogenesis. Several cardio-, reno-, and cerebrovascular diseases begin with the dysfunction of endothelial cells, and more recently, COVID-19 was also associated with endothelial disease highlighting the need to monitor its function towards prevention and reduction of vascular dysfunction. Endothelial cells are an important therapeutic target in predictive, preventive, and personalised (3P) medicine with upmost importance in vascular diseases. The development of novel non-invasive techniques to access endothelial dysfunction for use in combination with existing clinical imaging modalities provides a feasible opportunity to reduce the burden of vascular disease. This review summarises recent advances in the principles of endothelial function measurements. This article presents an overview of invasive and non-invasive techniques to determine vascular function and their major advantages and disadvantages. In addition, the article describes mechanisms underlying the regulation of vascular function and dysfunction and potential new biomarkers of endothelial damage. Recognising these biomarkers is fundamental towards a shift from reactive to 3P medicine in the vascular field. Identifying vascular dysfunction earlier with non-invasive or minimally invasive techniques adds value to predictive diagnostics and targeted prevention (primary, secondary, tertiary care). In addition, vascular dysfunction is a potential target for treatments tailored to the person.
Collapse
|
5
|
Park W, Yiu C, Liu Y, Wong TH, Huang X, Zhou J, Li J, Yao K, Huang Y, Li H, Li J, Jiao Y, Shi R, Yu X. High Channel Temperature Mapping Electronics in a Thin, Soft, Wireless Format for Non-Invasive Body Thermal Analysis. BIOSENSORS 2021; 11:bios11110435. [PMID: 34821651 PMCID: PMC8615861 DOI: 10.3390/bios11110435] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/29/2021] [Accepted: 10/29/2021] [Indexed: 11/16/2022]
Abstract
Hemodynamic status has been perceived as an important diagnostic value as fundamental physiological health conditions, including decisive signs of fatal diseases like arteriosclerosis, can be diagnosed by monitoring it. Currently, the conventional hemodynamic monitoring methods highly rely on imaging techniques requiring inconveniently large numbers of operation procedures and equipment for mapping and with a high risk of radiation exposure. Herein, an ultra-thin, noninvasive, and flexible electronic skin (e-skin) hemodynamic monitoring system based on the thermal properties of blood vessels underneath the epidermis that can be portably attached to the skin for operation is introduced. Through a series of thermal sensors, the temperatures of each subsection of the arrayed sensors are observed in real-time, and the measurements are transmitted and displayed on the screen of an external device wirelessly through a Bluetooth module using a graphical user interface (GUI). The degrees of the thermal property of subsections are indicated with a spectrum of colors that specify the hemodynamic status of the target vessel. In addition, as the sensors are installed on a soft substrate, they can operate under twisting and bending without any malfunction. These characteristics of e-skin sensors exhibit great potential in wearable and portable diagnostics including point-of-care (POC) devices.
Collapse
Affiliation(s)
- Wooyoung Park
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Chunki Yiu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
| | - Yiming Liu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Tsz Hung Wong
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Xingcan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Jingkun Zhou
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
| | - Jian Li
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
| | - Kuanming Yao
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Ya Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
| | - Hu Li
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Jiyu Li
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
| | - Yanli Jiao
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Rui Shi
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
| | - Xinge Yu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China; (W.P.); (C.Y.); (Y.L.); (T.H.W.); (X.H.); (J.Z.); (J.L.); (K.Y.); (Y.H.); (H.L.); (J.L.); (Y.J.); (R.S.)
- Hong Kong Center for Cerebra-Cardiovascular Health Engineering, Hong Kong Science Park, New Territories, Hong Kong 999077, China
- Correspondence:
| |
Collapse
|
6
|
Monitoring skin blood flow to rapidly identify alterations in tissue perfusion during fluid removal using continuous veno-venous hemofiltration in patients with circulatory shock. Ann Intensive Care 2021; 11:59. [PMID: 33855645 PMCID: PMC8046875 DOI: 10.1186/s13613-021-00847-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 03/29/2021] [Indexed: 12/13/2022] Open
Abstract
Background Continuous veno-venous hemofiltration (CVVH) can be used to reduce fluid overload and tissue edema, but excessive fluid removal may impair tissue perfusion. Skin blood flow (SBF) alters rapidly in shock, so its measurement may be useful to help monitor tissue perfusion. Methods In a prospective, observational study in a 35-bed department of intensive care, all patients with shock who required fluid removal with CVVH were considered for inclusion. SBF was measured on the index finger using skin laser Doppler (Periflux 5000, Perimed, Järfälla, Sweden) for 3 min at baseline (before starting fluid removal, T0), and 1, 3 and 6 h after starting fluid removal. The same fluid removal rate was maintained throughout the study period. Patients were grouped according to absence (Group A) or presence (Group B) of altered tissue perfusion, defined as a 10% increase in blood lactate from T0 to T6 with the T6 lactate ≥ 1.5 mmol/l. Receiver operating characteristic curves were constructed and areas under the curve (AUROC) calculated to identify variables predictive of altered tissue perfusion. Data are reported as medians [25th–75th percentiles]. Results We studied 42 patients (31 septic shock, 11 cardiogenic shock); median SOFA score at inclusion was 9 [8–12]. At T0, there were no significant differences in hemodynamic variables, norepinephrine dose, lactate concentration, ScvO2 or ultrafiltration rate between groups A and B. Cardiac index and MAP did not change over time, but SBF decreased in both groups (p < 0.05) throughout the study period. The baseline SBF was lower (58[35–118] vs 119[57–178] perfusion units [PU], p = 0.03) and the decrease in SBF from T0 to T1 (ΔSBF%) higher (53[39–63] vs 21[12–24]%, p = 0.01) in group B than in group A. Baseline SBF and ΔSBF% predicted altered tissue perfusion with AUROCs of 0.83 and 0.96, respectively, with cut-offs for SBF of ≤ 57 PU (sensitivity 78%, specificity 87%) and ∆SBF% of ≥ 45% (sensitivity 92%, specificity 99%). Conclusion Baseline SBF and its early reduction after initiation of fluid removal using CVVH can predict worsened tissue perfusion, reflected by an increase in blood lactate levels. Supplementary Information The online version contains supplementary material available at 10.1186/s13613-021-00847-z.
Collapse
|
7
|
de Paula MP, Moraes AB, de Souza MDGC, Cavalari EMR, Campbell RC, Fernandes GDS, Farias MLF, Mendonça LMC, Madeira M, Bouskela E, Kraemer-Aguiar LG, Vieira Neto L. Cortisol level after dexamethasone suppression test in patients with non-functioning adrenal incidentaloma is positively associated with the duration of reactive hyperemia response on microvascular bed. J Endocrinol Invest 2021; 44:609-619. [PMID: 32686043 DOI: 10.1007/s40618-020-01360-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 07/09/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE Data on endothelial derangements in patients with non-functioning adrenal incidentaloma (NFAI) are scarce. METHODS We investigated if NFAI patients present clinical, biochemical and endothelial alterations compared to individuals without an adrenal lesion and also the associations among these variables. Forty-two NFAI and 40 controls were evaluated. NFAI diagnosis and controls were defined according to the current guidelines and based on a normal adrenal imaging exam, respectively. Body composition was evaluated by dual emission X-ray absorptiometry. Endothelial reactivity was assessed by two methods: tonometry (Endo-PAT®) and laser speckle contrast imaging (LSCI). RESULTS There were no differences between groups regarding age, gender, ethnicity, smoking status, and statin use. The frequency of metabolic syndrome according to the International Diabetes Federation criteria was 69% and 57.9%, respectively in NFAI and controls (p = 0.36), whereas the atherosclerotic cardiovascular disease (ASCVD) risk was 63.4% and 66.7% (p = 0.81). The clinical, laboratory, and anthropometric characteristics, as well as body composition, were similar between the groups. Additionally, any differences between groups were observed on endothelial reactivity tests. Nevertheless, we noted an association between cortisol levels after 1 mg-dexamethosone suppression test (1 mg-DST) and the duration of post-occlusive reactive hyperemia tested on microcirculation (r = 0.30; p = 0.03). NFAI patients require more antihypertensive drugs to achieve blood pressure control (p = 0.04). The number of antihypertensive drugs used to control blood pressure correlated with cortisol levels after 1 mg-DST (r = 0.29; p = 0.03). CONCLUSIONS Since both groups herein investigated had a high frequency of metabolic syndrome and ASCVD risk, it might explain similarities observed on endothelial reactivity. Nevertheless, prolonged reactive hyperemia response on microcirculation was correlated with cortisol levels under suppression.
Collapse
Affiliation(s)
- M P de Paula
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - A B Moraes
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - M das Graças Coelho de Souza
- Laboratory for Clinical and Experimental Research on Vascular Biology, Biomedical Center, State University of Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil
| | - E M R Cavalari
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - R C Campbell
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - G da Silva Fernandes
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - M L F Farias
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - L M C Mendonça
- Department of Internal Medicine and Rheumatology Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Rio de Janeiro, RJ, Brazil
| | - M Madeira
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil
| | - E Bouskela
- Laboratory for Clinical and Experimental Research on Vascular Biology, Biomedical Center, State University of Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil
| | - L G Kraemer-Aguiar
- Laboratory for Clinical and Experimental Research on Vascular Biology, Biomedical Center, State University of Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil
- Endocrinology, Department of Internal Medicine, Faculty of Medical Sciences, State University of Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil
| | - L Vieira Neto
- Department of Internal Medicine and Endocrine Unit, Federal University of Rio de Janeiro, School of Medicine, Clementino Fraga Filho University Hospital, Professor Rodolpho Paulo Rocco Street, 255, 9th Floor, Rio de Janeiro, RJ, Brazil.
| |
Collapse
|
8
|
Tesselaar E, Farnebo S. Objective assessment of skin microcirculation using a smartphone camera. Skin Res Technol 2020; 27:138-144. [PMID: 32667094 DOI: 10.1111/srt.12919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/20/2020] [Indexed: 11/26/2022]
Abstract
BACKGROUND Existing techniques for assessment of microcirculation are limited by their large size and high costs and are often not so easy to use. Advances in mobile technology have enabled great improvements in smartphone sensor technology. In this study, we used SkinSight, an app for iPhone and iPad, to measure changes in skin microcirculation during physiological provocations. The system estimates changes in the concentration of hemoglobin in the skin by analyzing the reflected light emitted from the built-in light-emitting diode and detected by the camera of the smartphone. METHODS A relative hemoglobin (Hb) index was measured during a 5-min arterial occlusion, post-occlusive reactive hyperemia, and a 5-min venous occlusion in 10 healthy subjects, on two separate days. The index was calculated in an area of the skin from the color information in the images acquired by the phone camera. Polarized light spectroscopy imaging was used to measure changes in red blood cell concentration for comparison. RESULTS During arterial occlusion, relative Hb index was unchanged compared to baseline (P = .40). After release of the cuff, a sudden 60%-75% increase in Hb index was observed (P < .001) followed by a gradual return to baseline. During venous occlusion, Hb index increased by 80% (P < .001) followed by a gradual decrease to baseline after reperfusion. Day-to-day reproducibility of the relative Hb index was excellent (ICC: 0.92, r = 0.94), although relative Hb index was consistently higher during the second day, possibly as a result of changed lighting conditions or calibration issues. CONCLUSION Microvascular responses to physiological provocations in the skin can be accurately and reproducibly measured using a smartphone application. Although the system offers a handheld, easy to use and flexible technique for skin microvascular assessment, the effects of lighting on the measured values and need for calibration need to be further investigated.
Collapse
Affiliation(s)
- Erik Tesselaar
- Department of Radiation Physics, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Simon Farnebo
- Department of Hand and Plastic Surgery and Burns and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| |
Collapse
|
9
|
Zwanenburg PR, Backer SFM, Obdeijn MC, Lapid O, Gans SL, Boermeester MA. A Systematic Review and Meta-Analysis of the Pressure-Induced Vasodilation Phenomenon and Its Role in the Pathophysiology of Ulcers. Plast Reconstr Surg 2019; 144:669e-681e. [PMID: 31568315 DOI: 10.1097/prs.0000000000006090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Physiologic studies show that tissue perfusion increases during moderate amounts of tissue compression. This is attributed to sensory nerves initiating a vasodilatory cascade referred to as pressure-induced vasodilation. METHODS PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched for studies investigating perfusion during pressure exposure longer than 10 minutes. Retrieved studies were assessed using the Office of Health Assessment and Translation Risk of Bias Rating Tool for Human and Animal Studies. Results were pooled with random effects models. The body of evidence was rated using the Office of Health Assessment and Translation approach. RESULTS Twenty-nine articles were included, of which 19 articles were included in meta-analyses. The evidence indicates that moderate amounts of tissue compression have the capacity to increase perfusion in healthy humans by 46 percent (95 percent CI, 30 to 62 percent). Using the Office of Health Assessment and Translation approach, the authors found a high level of confidence in the body of evidence. Pressure-induced vasodilation blockade was associated with increased pressure ulcer formation. Pressure-induced vasodilation was impaired by neuropathy and by the drugs diclofenac and amiloride. CONCLUSIONS This systematic review and meta-analysis indicates that healthy humans have the capacity to increase local perfusion in response to mechanical stress resulting from tissue compression. Because pressure-induced vasodilation is mediated by sensory nerves, pressure-induced vasodilation emphasizes the importance of sensory innervation for durable tissue integrity. Pressure-induced vasodilation impairment seems to provide a complementary explanation for the susceptibility of neuropathic tissues to pressure-induced lesions.
Collapse
Affiliation(s)
- Pieter R Zwanenburg
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| | - Sophia F M Backer
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| | - Miryam C Obdeijn
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| | - Oren Lapid
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| | - Sarah L Gans
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| | - Marja A Boermeester
- From the Department of Surgery, Amsterdam Gastroenterology and Metabolism, Amsterdam Infection and Immunity, and the Department of Plastic, Reconstructive and Hand Surgery, Amsterdam University Medical Center, University of Amsterdam
| |
Collapse
|
10
|
Liu M, Drexler W. Optical coherence tomography angiography and photoacoustic imaging in dermatology. Photochem Photobiol Sci 2019; 18:945-962. [PMID: 30735220 DOI: 10.1039/c8pp00471d] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Optical coherence tomography angiography (OCTA) is a relatively novel functional extension of the widely accepted ophthalmic imaging tool named optical coherence tomography (OCT). Since OCTA's debut in ophthalmology, researchers have also been trying to expand its translational application in dermatology. The ability of OCTA to resolve microvasculature has shown promising results in imaging skin diseases. Meanwhile, photoacoustic imaging (PAI), which uses laser pulse induced ultrasound waves as the signal, has been studied to differentiate human skin layers and to help in skin disease diagnosis. This perspective article gives a short review of OCTA and PAI in the field of photodermatology. After an introduction to the principles of OCTA and PAI, we describe the most updated results of skin disease imaging using these two optical imaging modalities. We also place emphasis on dual modality imaging combining OCTA and photoacoustic tomography (PAT) for dermatological applications. In the end, the challenges and prospects of these two imaging modalities in dermatology are discussed.
Collapse
Affiliation(s)
- Mengyang Liu
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria.
| | | |
Collapse
|
11
|
Patnaik SK, Kumar P, Bamal M, Patel S, Yadav MP, Kumar V, Sinha A, Bagga A, Kanitkar M. Cardiovascular outcomes of Nephrotic syndrome in childhood (CVONS) study: a protocol for prospective cohort study. BMC Nephrol 2018; 19:81. [PMID: 29614967 PMCID: PMC5883594 DOI: 10.1186/s12882-018-0878-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 03/19/2018] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Nephrotic syndrome (NS) is characterized by dyslipidemia which is a well-known risk factor for atherogenesis. Atherosclerosis in childhood is mostly subclinical and endothelial dysfunction is known to precede this. Evidence for screening for endothelial dysfunction and cardiovascular risk factors and early identification of premature onset of atherosclerosis in childhood NS remains tenuous in the absence of well-designed prospective studies addressing cardiovascular comorbidity in NS. The objective of our study is to examine endothelial dysfunction and short-term cardiovascular outcomes in a carefully phenotyped cohort of patients with Nephrotic syndrome as compared to healthy controls. METHODS In a multi-centric prospective cohort study, 70 Steroid Resistant NS (SRNS), 70 Steroid Sensitive (SSNS) patients along with 70 Healthy Controls are being recruited. After a baseline assessment of functional and structural status of heart (2D Echocardiography), arteries (Carotid Doppler and Intima Media Thickness measurements) and microcirculation [a combination of 2D Echocardiography, Laser Doppler Flowmetry (LDF) and Brachial Artery Flow mediated dilation (FMD) and Nail Fold Capillaroscopy (NFC)], the patients are being investigated for endothelial dysfunction. Venous blood sample (15 ml) is being collected for routine investigations and assay of biochemical endothelial markers through Flow Cytometry. The patients will be followed up at 12 months and 24 months after the recruitment to look for any change from baseline period. DISCUSSION This study will able to provide a better understanding of the epidemiology of endothelial dysfunction and associated subclinical cardiovascular co-morbidity in childhood NS. Findings on characterization of prevalence of endothelial dysfunction and subclinical markers may be used to design future randomized controlled trials for evaluating the efficacy of preventive and therapeutic interventions in reducing the incidence of cardiovascular disease.
Collapse
Affiliation(s)
- S K Patnaik
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India.
| | - P Kumar
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India
| | - M Bamal
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India
| | - S Patel
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India
| | - M P Yadav
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India
| | - V Kumar
- Department of Pediatrics, Army Hospital Research and Referral , Delhi, India
| | - A Sinha
- Division of Pediatric Nephrology and ICMR Center for Advanced Research In Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - A Bagga
- Division of Pediatric Nephrology and ICMR Center for Advanced Research In Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - M Kanitkar
- Armed Forced Medical College, Pune, India
| |
Collapse
|
12
|
Belykh E, Yagmurlu K, Martirosyan NL, Lei T, Izadyyazdanabadi M, Malik KM, Byvaltsev VA, Nakaji P, Preul MC. Laser application in neurosurgery. Surg Neurol Int 2017; 8:274. [PMID: 29204309 PMCID: PMC5691557 DOI: 10.4103/sni.sni_489_16] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 08/18/2017] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Technological innovations based on light amplification created by stimulated emission of radiation (LASER) have been used extensively in the field of neurosurgery. METHODS We reviewed the medical literature to identify current laser-based technological applications for surgical, diagnostic, and therapeutic uses in neurosurgery. RESULTS Surgical applications of laser technology reported in the literature include percutaneous laser ablation of brain tissue, the use of surgical lasers in open and endoscopic cranial surgeries, laser-assisted microanastomosis, and photodynamic therapy for brain tumors. Laser systems are also used for intervertebral disk degeneration treatment, therapeutic applications of laser energy for transcranial laser therapy and nerve regeneration, and novel diagnostic laser-based technologies (e.g., laser scanning endomicroscopy and Raman spectroscopy) that are used for interrogation of pathological tissue. CONCLUSION Despite controversy over the use of lasers for treatment, the surgical application of lasers for minimally invasive procedures shows promising results and merits further investigation. Laser-based microscopy imaging devices have been developed and miniaturized to be used intraoperatively for rapid pathological diagnosis. The multitude of ways that lasers are used in neurosurgery and in related neuroclinical situations is a testament to the technological advancements and practicality of laser science.
Collapse
Affiliation(s)
- Evgenii Belykh
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
- Department of Neurosurgery, Irkutsk State Medical University, Irkutsk, Russia
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Kaan Yagmurlu
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Nikolay L. Martirosyan
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Ting Lei
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Mohammadhassan Izadyyazdanabadi
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Kashif M. Malik
- University of Arizona College of Medicine, Tucson, Arizona, USA
| | - Vadim A. Byvaltsev
- Department of Neurosurgery, Irkutsk State Medical University, Irkutsk, Russia
| | - Peter Nakaji
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Mark C. Preul
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| |
Collapse
|
13
|
Nakatani T, Hashimoto T, Sutou I, Saito Y. Retention of finger blood flow against postural change as an indicator of successful sympathetic block in the upper limb. J Pain Res 2017; 10:475-479. [PMID: 28280382 PMCID: PMC5338961 DOI: 10.2147/jpr.s124627] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Sympathetic block in the upper limb has diagnostic, therapeutic and prognostic utility for disorders in the upper extremity that are associated with sympathetic disturbances. Increased skin temperature and decreased sweating are used to identify the adequacy of sympathetic block in the upper limb after stellate ganglion block (SGB). Baroreflexes elicited by postural change induce a reduction in peripheral blood flow by causing sympathetic vasoconstriction. We hypothesized that sympathetic block in the upper limb reduces the decrease in finger blood flow caused by baroreflexes stimulated by postural change from the supine to long sitting position. This study evaluated if sympathetic block of the upper limb affects the change in finger blood flow resulting from postural change. If change in finger blood flow would be kept against postural changes, it has a potential to be a new indicator of sympathetic blockade in the upper limb. Methods Subjects were adult patients who had a check-up at the Department of Pain Management in our university hospital over 2 years and 9 months from May 2012. We executed a total of 91 SGBs in nine patients (N=9), which included those requiring treatment for pain associated with herpes zoster in seven of the patients, tinnitus in one patient and upper limb pain in one patient. We checked for the following four signs after performing SGB: Horner’s sign, brachial nerve blockade, finger blood flow measured by a laser blood flow meter and skin temperature of the thumb measured by thermography, before and after SGB in the supine position and immediately after adopting the long sitting position. Results We executed a total of 91 SGBs in nine patients. Two SGBs were excluded from the analysis due to the absence of Horner’s sign. We divided 89 procedures into two groups according to elevation in skin temperature of the thumb: by over 1°C (sympathetic block group, n=62) and by <1°C (nonsympathetic block group, n=27). Finger blood flow decreased significantly just after a change in posture from the supine to long sitting position after SGB in both groups. In the sympathetic block group, the ratio of finger blood flow in the long sitting position/supine position with a change in posture significantly increased after SGB compared with before SGB (before SGB: range 0.09–0.94, median 0.53; after SGB: range 0.33–1.2, median 0.89, p<0.0001). Conclusion Our study shows that with sympathetic block in the upper limb, the ratio of finger blood flow significantly increases despite baroreflexes stimulated by postural change from the supine to long sitting position. Retention of finger blood flow against postural changes may be an indicator of sympathetic block in the upper limb after SGB or brachial plexus block.
Collapse
Affiliation(s)
- Toshihiko Nakatani
- Department of Palliative Care, Shimane University Faculty of Medicine, Izumo
| | | | - Ichiro Sutou
- Palliative Care Center, Shimane University Hospital, Izumo
| | - Yoji Saito
- Department of Anesthesiology, Shimane University Faculty of Medicine, Izumo, Japan
| |
Collapse
|
14
|
Fuchs D, Dupon PP, Schaap LA, Draijer R. The association between diabetes and dermal microvascular dysfunction non-invasively assessed by laser Doppler with local thermal hyperemia: a systematic review with meta-analysis. Cardiovasc Diabetol 2017; 16:11. [PMID: 28103890 PMCID: PMC5244618 DOI: 10.1186/s12933-016-0487-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 12/25/2016] [Indexed: 01/17/2023] Open
Abstract
Background/Introduction Diabetes and cardiovascular disease develop in concert with metabolic abnormalities mirroring and causing changes in the vasculature, particularly the microcirculation. The microcirculation can be affected in different parts of the body of which the skin is the most easily accessible tissue. Purpose The association between diabetes and dermal microvascular dysfunction has been investigated in observational studies. However, the strength of the association is unknown. Therefore we conducted a systematic review with meta-analysis on the association between diabetes and dermal microvascular dysfunction as assessed by laser Doppler/laser speckle contrast imaging with local thermal hyperaemia as non-invasive indicator of microvascular functionality. Methods PubMed and Ovid were systematically searched for eligible studies through March 2015. During the first selection, studies were included if they were performed in humans and were related to diabetes or glucose metabolism disorders and to dermal microcirculation. During the second step we selected studies based on the measurement technique, measurement location (arm or leg) and the inclusion of a healthy control group. A random effects model was used with the standardised mean difference as outcome measure. Calculations and imputation of data were done according to the Cochrane Handbook. Results Of the 1445 studies found in the first search, thirteen cross-sectional studies were included in the meta-analysis, comprising a total of 857 subjects. Resting blood flow was similar between healthy control subjects and diabetes patients. In contrast, the microvascular response to local skin heating was reduced in diabetic patients compared to healthy control subjects [pooled effect of −0.78 standardised mean difference (95% CI −1.06, −0.51)]. This effect is considered large according to Cohen’s effect size definition. The variability in effect size was high (heterogeneity 69%, p < 0.0001). However, subgroup analysis revealed no difference between the type and duration of diabetes and other health related factors, indicating that diabetes per se causes the microvascular dysfunction. Conclusion Our meta-analysis shows that diabetes is associated with a large reduction of dermal microvascular function in diabetic patients. The local thermal hyperaemia methodology may become a valuable non-invasive tool for diagnosis and assessing progress of diabetes-related microvascular complications, but standardisation of the technique and quality of study conduct is urgently required. Electronic supplementary material The online version of this article (doi:10.1186/s12933-016-0487-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Dagmar Fuchs
- Unilever Research and Development, Vlaardingen, Olivier van Noortlaan 120, PO Box 114, 3130 AC, Vlaardingen, The Netherlands.
| | - Pepijn P Dupon
- Unilever Research and Development, Vlaardingen, Olivier van Noortlaan 120, PO Box 114, 3130 AC, Vlaardingen, The Netherlands.,Faculty of Earth and Life Sciences, Free University Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
| | - Laura A Schaap
- Faculty of Earth and Life Sciences, Free University Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
| | - Richard Draijer
- Unilever Research and Development, Vlaardingen, Olivier van Noortlaan 120, PO Box 114, 3130 AC, Vlaardingen, The Netherlands
| |
Collapse
|
15
|
Population pharmacokinetic/pharmacodynamic modeling of histamine response measured by histamine iontophoresis laser Doppler. J Pharmacokinet Pharmacodyn 2016; 43:385-93. [PMID: 27307292 DOI: 10.1007/s10928-016-9478-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 06/08/2016] [Indexed: 10/21/2022]
Abstract
The epicutaneous histamine (EH) test is the current gold standard method for the clinical evaluation of allergic conditions. However, the EH method is limited in providing an objective and qualitative assessment of histamine pharmacodynamic response. The histamine iontophoresis with laser Doppler (HILD) monitoring method, an alternative method, allows a fixed dose of histamine to be delivered and provides an objective, continuous, and dynamic measurement of histamine epicutaneous response in children and adults. However, due to the high sampling frequency (up to 40 Hz), the output files are usually too cumbersome to be directly used for further analysis. In this study, we developed an averaging algorithm that efficiently reduces the HILD data in size. The reduced data was further analyzed and a population linked effect pharmacokinetic/pharmacodynamic (PK/PD) model was developed to describe the local histamine response. The model consisted of a one-compartment PK model and a direct-response fractional maximum effect (Emax) model. The parameter estimates were obtained as follows: absorption rate constant (ka), 0.094/min; absorption lag time (Tlag), 2.72 min; partitioning clearance from local depot to systemic circulation (CLpar), 0.0006 L/min; baseline effect (E0), 13.1 flux unit; Emax, 13.4; concentration at half maximum effect (EC50) 31.1 mg/L. Covariate analysis indicated that age and race had significant influence on Tlag and EC50, respectively.
Collapse
|
16
|
Nikolić M, Lim YL, Bertling K, Taimre T, Rakić AD. Multiple signal classification for self-mixing flowmetry. APPLIED OPTICS 2015; 54:2193-2198. [PMID: 25968500 DOI: 10.1364/ao.54.002193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/04/2015] [Indexed: 06/04/2023]
Abstract
For the first time to our knowledge, we apply the multiple signal classification (MUSIC) algorithm to signals obtained from a self-mixing flow sensor. We find that MUSIC accurately extracts the fluid velocity and exhibits a markedly better signal-to-noise ratio (SNR) than the commonly used fast Fourier transform (FFT) method. We compare the performance of the MUSIC and FFT methods for three decades of scatterer concentration and fluid velocities from 0.5 to 50 mm/s. MUSIC provided better linearity than the FFT and was able to accurately function over a wider range of algorithm parameters. MUSIC exhibited excellent linearity and SNR even at low scatterer concentration, at which the FFT's SNR decreased to impractical levels. This makes MUSIC a particularly attractive method for flow measurement systems with a low density of scatterers such as microfluidic and nanofluidic systems and blood flow in capillaries.
Collapse
|
17
|
Abstract
Smoking has a negative impact on skin health. Numerous studies have effectively linked smoking with delayed wound healing and healing complications. Research has identified cigarette smoking affects wound healing at a cellular level. Reducing fibroblast activity and keratinocyte migration. Such is the concern around the affects that smoking has on wound healing that some question whether smoking abstinence should be a pre requisite before some surgical procedures. This article will discuss current research and clinical studies that have investigated impaired wound healing as a result of cigarette smoking.
Collapse
|
18
|
Bagatin E, Miot HA, Soares JLM, Sanudo A, Afonso JPJM, de Barros Junior N, Talarico S. Long-wave infrared radiation reflected by compression stockings in the treatment of cellulite: a clinical double-blind, randomized and controlled study. Int J Cosmet Sci 2013; 35:502-9. [DOI: 10.1111/ics.12073] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 06/15/2013] [Indexed: 01/26/2023]
Affiliation(s)
- E. Bagatin
- Department of Dermatology; Federal University of São Paulo; R Borges Lagoa, 508; Sao Paulo; 04038-001; SP; Brazil
| | - H. A. Miot
- Dermatology Course; Faculdade de Medicina de Botucatu; School of Medicine of Botucatu; Universidade do Estado de São Paulo - UNESP; State University of São Paulo; Campus Universitário de Rubião Jr; Botucatu; 18618-970; SP; Brazil
| | - J. L. M. Soares
- Department of Dermatology; Federal University of São Paulo; R Borges Lagoa, 508; Sao Paulo; 04038-001; SP; Brazil
| | - A. Sanudo
- Department of Dermatology; Federal University of São Paulo; R Borges Lagoa, 508; Sao Paulo; 04038-001; SP; Brazil
| | - J. P. J. M. Afonso
- Department of Dermatology; Federal University of São Paulo; R Borges Lagoa, 508; Sao Paulo; 04038-001; SP; Brazil
| | - N. de Barros Junior
- Department of Surgery; Course of Vascular Surgery; UNIFESP; R Napoleao de Barros, 715; Sao Paulo; 04024002; SP; Brazil
| | - S. Talarico
- Department of Dermatology; Federal University of São Paulo; R Borges Lagoa, 508; Sao Paulo; 04038-001; SP; Brazil
| |
Collapse
|
19
|
García-Figueruelo A, Urbano J, Botrán M, González-Cortés R, Solana M, López-González J, López-Herce J. Evaluación de la perfusión tisular periférica mediante láser Doppler en niños en estado crítico. An Pediatr (Barc) 2013; 78:361-6. [DOI: 10.1016/j.anpedi.2012.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/11/2012] [Accepted: 09/22/2012] [Indexed: 11/16/2022] Open
|
20
|
Liang CP, Wu Y, Schmitt J, Bigeleisen PE, Slavin J, Jafri MS, Tang CM, Chen Y. Coherence-gated Doppler: a fiber sensor for precise localization of blood flow. BIOMEDICAL OPTICS EXPRESS 2013; 4:760-71. [PMID: 23667791 PMCID: PMC3646602 DOI: 10.1364/boe.4.000760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 03/23/2013] [Accepted: 03/23/2013] [Indexed: 05/22/2023]
Abstract
Miniature optical sensors that can detect blood vessels in front of advancing instruments will significantly benefit many interventional procedures. Towards this end, we developed a thin and flexible coherence-gated Doppler (CGD) fiber probe (O.D. = 0.125 mm) that can be integrated with minimally-invasive tools to provide real-time audio feedback of blood flow at precise locations in front of the probe. Coherence-gated Doppler (CGD) is a hybrid technology with features of laser Doppler flowmetry (LDF) and Doppler optical coherence tomography (DOCT). Because of its confocal optical design and coherence-gating capabilities, CGD provides higher spatial resolution than LDF. And compared to DOCT imaging systems, CGD is simpler and less costly to produce. In vivo studies of rat femoral vessels using CGD demonstrate its ability to distinguish between artery, vein and bulk movement of the surrounding soft tissue. Finally, by placing the CGD probe inside a 30-gauge needle and advancing it into the brain of an anesthetized sheep, we demonstrate that it is capable of detecting vessels in front of advancing probes during simulated stereotactic neurosurgical procedures. Using simultaneous ultrasound (US) monitoring from the surface of the brain we show that CGD can detect at-risk blood vessels up to 3 mm in front of the advancing probe. The improved spatial resolution afforded by coherence gating combined with the simplicity, minute size and robustness of the CGD probe suggest it may benefit many minimally invasive procedures and enable it to be embedded into a variety of surgical instruments.
Collapse
Affiliation(s)
- Chia-Pin Liang
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Yalun Wu
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD 20742, USA
| | - Joe Schmitt
- St. Jude Medical, Inc., Westford, MA 01886, USA
| | - Paul E. Bigeleisen
- Depatment of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Justin Slavin
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - M. Samir Jafri
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Research Service, Baltimore VA Medical Center, Baltimore, MD 21201, USA
| | - Cha-Min Tang
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Research Service, Baltimore VA Medical Center, Baltimore, MD 21201, USA
| | - Yu Chen
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD 20742, USA
| |
Collapse
|
21
|
Goldman J, Becker ML, Jones B, Clements M, Leeder JS. Development of biomarkers to optimize pediatric patient management: what makes children different? Biomark Med 2012; 5:781-94. [PMID: 22103612 DOI: 10.2217/bmm.11.96] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Despite the frequent utilization of biomarkers in medical practice, there is a relative paucity of information regarding validated pediatric biomarkers. Frequently, biomarkers found to be efficacious in adults are extrapolated to the pediatric clinical setting without considering that the pathogenesis of many diseases is distinctly different in children, and ontogeny directly influences disease evolution and therapeutic response in children. New and innovative approaches are necessary to provide reliable, validated biomarkers that can be used to improve and advance pediatric medical care.
Collapse
Affiliation(s)
- Jennifer Goldman
- Division of Clinical Pharmacology & Medical Toxicology, Children's Mercy Hospitals & Clinics & University of Missouri-Kansas City, Kansas City, MO, USA
| | | | | | | | | |
Collapse
|
22
|
Microvascular Blood Flow Changes in the Small Intestinal Wall During Conventional Negative Pressure Wound Therapy and Negative Pressure Wound Therapy Using a Protective Disc Over the Intestines in Laparostomy. Ann Surg 2012; 255:171-5. [DOI: 10.1097/sla.0b013e31823c9ffa] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
23
|
Leutenegger M, Martin-Williams E, Harbi P, Thacher T, Raffoul W, André M, Lopez A, Lasser P, Lasser T. Real-time full field laser Doppler imaging. BIOMEDICAL OPTICS EXPRESS 2011; 2:1470-7. [PMID: 21698011 PMCID: PMC3114216 DOI: 10.1364/boe.2.001470] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 05/06/2011] [Accepted: 05/05/2011] [Indexed: 05/20/2023]
Abstract
We present a full field laser Doppler imaging instrument, which enables real-time in vivo assessment of blood flow in dermal tissue and skin. This instrument monitors the blood perfusion in an area of about 50 cm(2) with 480 × 480 pixels per frame at a rate of 12-14 frames per second. Smaller frames can be monitored at much higher frame rates. We recorded the microcirculation in healthy skin before, during and after arterial occlusion. In initial clinical case studies, we imaged the microcirculation in burned skin and monitored the recovery of blood flow in a skin flap during reconstructive surgery indicating the high potential of LDI for clinical applications. Small animal imaging in mouse ears clearly revealed the network of blood vessels and the corresponding blood perfusion.
Collapse
Affiliation(s)
- Marcel Leutenegger
- Laboratoire d’Optique Biomédicale, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Erica Martin-Williams
- Laboratoire d’Optique Biomédicale, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Pascal Harbi
- Aïmago SA, Parc Scientifique EPFL, Lausanne, Switzerland
| | - Tyler Thacher
- Aïmago SA, Parc Scientifique EPFL, Lausanne, Switzerland
| | - Wassim Raffoul
- Plastic Surgery Department, Lausanne University Hospital, Lausanne, Switzerland
| | - Marc André
- Aïmago SA, Parc Scientifique EPFL, Lausanne, Switzerland
| | - Antonio Lopez
- Laboratoire d’Optique Biomédicale, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Philippe Lasser
- Service d'anesthésiologie, réanimation et antalgie, Etablissements hospitaliers du Nord Vaudois, Yverdon, Switzerland
| | - Theo Lasser
- Laboratoire d’Optique Biomédicale, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| |
Collapse
|
24
|
|
25
|
Heiskanen T, Mätzke S, Haakana S, Gergov M, Vuori E, Kalso E. Transdermal fentanyl in cachectic cancer patients. Pain 2009; 144:218-22. [DOI: 10.1016/j.pain.2009.04.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 04/09/2009] [Accepted: 04/14/2009] [Indexed: 11/25/2022]
|
26
|
Koskela M, Gäddnäs F, Ala-Kokko TI, Laurila JJ, Saarnio J, Oikarinen A, Koivukangas V. Epidermal wound healing in severe sepsis and septic shock in humans. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2009; 13:R100. [PMID: 19552820 PMCID: PMC2717472 DOI: 10.1186/cc7932] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 02/17/2009] [Accepted: 06/24/2009] [Indexed: 12/30/2022]
Abstract
Introduction The effect of sepsis on epidermal wound healing has not been previously studied. It was hypothesised that epidermal wound healing is disturbed in severe sepsis. Methods Blister wounds were induced in 35 patients with severe sepsis and in 15 healthy controls. The healing of the wounds was followed up by measuring transepidermal water loss and blood flow in the wound, reflecting the restoration of the epidermal barrier function and inflammation, respectively. The first set of suction blisters (early wound) was made within 48 hours of the first sepsis-induced organ failure and the second set (late wound) four days after the first wound. In addition, measurements were made on the intact skin. Results The average age of the whole study population was 62 years (standard deviation [SD] 12). The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score on admission was 25 (SD 8). The two most common causes of infections were peritonitis and pneumonia. Sixty-six percent of the patients developed multiple organ failure. The decrease in water evaporation from the wound during the first four days was lower in septic patients than in the control subjects (56 g/m2 per hour versus 124 g/m2 per hour, P = 0.004). On the fourth day, septic patients had significantly higher blood flow in the wound compared with the control subjects (septic patients 110 units versus control subjects 47 units, P = 0.001). No difference in transepidermal water loss from the intact skin was found between septic patients and controls. Septic patients had higher blood flow in the intact skin on the fourth and on the eighth day of study compared with the controls. Conclusions The restoration of the epidermal barrier function is delayed and wound blood flow is increased in patients with severe sepsis.
Collapse
Affiliation(s)
- Marjo Koskela
- Department of Anesthesiology, Division of Intensive Care Medicine, Oulu University Hospital, 90029 OUH, Finland.
| | | | | | | | | | | | | |
Collapse
|
27
|
Dawn A, Thevarajah S, Cayce KA, Carroll CL, Duque ML, Chan YH, Jorizzo JL, Yosipovitch G. Cutaneous blood flow in dermatomyositis and its association with disease severity. Skin Res Technol 2007; 13:285-92. [PMID: 17610650 DOI: 10.1111/j.1600-0846.2007.00226.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Several studies using nailfold capillary microscopes have demonstrated capillary changes in patients with dermatomyositis (DM); however, no previous study has examined cutaneous blood flow in this disease. PURPOSE To determine cutaneous blood flow in involved and non-involved skin surfaces of patients with DM and to assess possible correlation with clinical measures of disease severity. METHODS Using a Laser Doppler perfusion imager, cutaneous blood flow was measured at six targeted sites of involved and apparently non-involved skin of 13 DM patients and the corresponding non-involved sites of 13 healthy controls. Overall disease severity of DM patients was determined by physician's global assessment (PGA), creatinine phosphokinase (CPK) levels, medical research council (MRC) scores, and the DM skin severity index (DSSI). RESULTS Skin blood flow was significantly elevated in involved vs. non-involved skin of DM patients at all anatomic sites measured: periungual (P=0.001), knuckle (P=0.001), elbow (P=0.013), periorbital (P=0.015), chest (P=0.028), and back (P=0.001). Blood flow was also higher in apparently non-involved skin of DM patients vs. skin of healthy controls at all anatomic sites, although statistical significance was not achieved. A significant negative correlation was observed between the DSSI and blood flow in involved skin of the chest (P=0.003), back (P=0.002), and knuckle (P=0.026). CONCLUSION DM is associated with significantly increased cutaneous blood flow, even at sites where no erythema is evident. This suggests significant involvement of the skin vasculature in this disease process.
Collapse
Affiliation(s)
- Aerlyn Dawn
- Department of Dermatology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Kunkel CF, Figoni SF, Baumgarten JM, Carvalho CM, Kim HS, Oshiro RL, Zirovich MD, Scremin OU, Scremin AME. Scanning Laser-Doppler Imaging of Leg- and Foot-Skin Perfusion in Normal Subjects. Am J Phys Med Rehabil 2007; 86:262-71. [PMID: 17413539 DOI: 10.1097/phm.0b013e3180383526] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To report normal values of skin perfusion in healthy subjects in three age groups using a laser Doppler imager; to determine differences attributable to gender, age, site, and use of red or near-infrared lasers; and to correlate transcutaneous oxygen with laser flux values. DESIGN Flux and transcutaneous oxygen were measured at ten sites in the lower extremity in 60 subjects from three age groups. Heated and unheated sites were scanned with red and near-infrared lasers. RESULTS Heat hyperemia was prominent at all sites. Small, statistically significant mean +/- SD differences were found between heated and nonheated sites for the red and near-infrared lasers (P = 0.02). All flux ratios were independent of gender but were higher in the oldest group. Plantar sites demonstrated higher flux in unheated areas and lower flux ratios compared with leg sites. Transcutaneous oxygen did not correlate significantly with flux for either laser type. CONCLUSIONS Scanning laser-Doppler imaging flux values provide a reference for identifying patients at risk for tissue ischemia and poor healing potential caused by impaired circulatory reserve in the legs and distal feet. The lack of correlation between flux and transcutaneous oxygen in healthy individuals suggests that they measure different physiologic processes.
Collapse
Affiliation(s)
- Charles F Kunkel
- Department of Physical Medicine and Rehabilitation, VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Weibel L, Howell KJ, Visentin MT, Rudiger A, Denton CP, Zulian F, Woo P, Harper JI. Laser Doppler flowmetry for assessing localized scleroderma in children. ACTA ACUST UNITED AC 2007; 56:3489-95. [PMID: 17907196 DOI: 10.1002/art.22920] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Assessment of disease activity is a major challenge in the management of children with localized scleroderma. The aim of this study was to evaluate the role of laser Doppler flowmetry (LDF) in comparison with infrared thermography in the detection of scleroderma disease activity. METHODS In 41 children with localized scleroderma, 111 lesions were assessed on 2 separate occasions, by clinical examination, LDF, and thermography. Measurements from contralateral areas of unaffected skin served as intrapatient controls, and differences in blood flow and temperature were calculated between the corresponding sites. The sensitivity and specificity to detect clinically active lesions were compared between LDF and thermography. RESULTS Seventy-five active lesions (34%) and 147 inactive lesions (66%) were identified clinically. The median relative increase in blood flow measured by LDF was +89% (range -69% to +449%) for clinically active lesions and +11% (range -46% to +302%) for clinically inactive lesions (P < 0.001). Thermography showed a median difference in temperature of +0.5 degrees C (range -0.1 degrees C to +4.1 degrees C) and +0.3 degrees C (range -1.9 degrees C to +2.7 degrees C) for clinically active lesions and clinically inactive lesions, respectively (P = 0.024). Using a cutoff level of 39% to indicate increase in blood flow, a sensitivity of 80% and specificity of 77% to detect clinically active lesions were observed; for thermography, no useful cutoff level was identified. The correlation between differences in blood flow and differences in temperature was small, but significant (r2 = 0.120, P < 0.001). CONCLUSION LDF is a helpful, noninvasive diagnostic technique that can be used to discriminate disease activity in children with localized scleroderma, and is more accurate than thermography for this purpose.
Collapse
Affiliation(s)
- Lisa Weibel
- Great Ormond Street Hospital for Children, London, UK.
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Li L, Mac-Mary S, Sainthillier JM, Nouveau S, de Lacharriere O, Humbert P. Age-Related Changes of the Cutaneous Microcirculation in vivo. Gerontology 2006; 52:142-53. [PMID: 16645294 DOI: 10.1159/000091823] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2005] [Accepted: 12/12/2005] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The architectural frameworks of the skin microcirculation are rather complex and change continuously with aging. But these changes are yet poorly documented in vivo. OBJECTIVES Using non-invasive methods belonging to the field of biometrology, the study aimed to investigate quantitatively the changes of the cutaneous microvasculature in different anatomic sites with age. METHODS Measurements were performed on crow's feet, forehead, volar forearm and dorsum of hand in 50 women (aged 20-74 years who consisted of 10 probands in each live decades). The superficial vascular plexus was scanned by videocapillaroscopy and assessed with the software Capilab Toolbox. The subpapillary vascular plexus was explored with laser Doppler flowmetry. The skin color a* was analyzed by chromametry. RESULTS A marked site and age effect on the skin microcirculation has been demonstrated. The density of capillary loops in the eldest group decreased by about 40-70% compared with the youngest group whereas the vascular length increased by 35-156%. The capillary density in the back of the hand was 4 times higher than in the crow's feet. The vascular length in the crow's feet was 3 times longer than in the back of the hand. Both blood flow and skin redness (a*) increased also with age. CONCLUSION Both morphology and quantification of the cutaneous microvasculature showed changes with site and age. Videocapillaroscopy associated to an image processing and laser Doppler flowmetry revealed different vascular layers. So the combination of both instruments offers an easy way to observe the architectural frameworks in vivo.
Collapse
Affiliation(s)
- Li Li
- Cutaneous Engineering and Biology Laboratory and IFR 133 Cell and Tissue Engineering and Biology, University of Franche-Comté, Besançon, France
| | | | | | | | | | | |
Collapse
|
31
|
Li L, Mac-Mary S, Marsaut D, Sainthillier JM, Nouveau S, Gharbi T, de Lacharriere O, Humbert P. Age-related changes in skin topography and microcirculation. Arch Dermatol Res 2005; 297:412-6. [PMID: 16328340 DOI: 10.1007/s00403-005-0628-y] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Accepted: 11/10/2005] [Indexed: 11/29/2022]
Abstract
Skin topography and microvasculature undergo characteristic changes with age. Although several non-invasive bioengineering methods are currently available to measure them quantitatively, few publications have referred to their relationship with age in different anatomical sites. This study was carried out to observe the age-related changes of the skin topography and skin microcirculation. The microrelief was assessed with special processing software from scanning by interference fringe profilometry of silicone replicas performed on two sites (volar forearm and back of hand) on 50 female volunteers (aged 20-74 years who consisted of ten probands in each decade). The superficial vascular network of both sites was assessed by videocapillaroscopy, and the subpapillary vascular plexus was studied with laser Doppler flowmetry. Skin color, which is affected by blood flow, was observed by colorimeter. The skin roughness and the mean height between peak and valley increased with age. There were statistically significant differences between the evaluated sites. This study also shows that the capillary loops in the dermal papillae decrease but the subpapillary plexus increase with age. The interference fringe profilometry associated with videocapillaroscopy may be useful and accurate to measure the efficacy of medical or cosmetic products to delay skin aging.
Collapse
Affiliation(s)
- Li Li
- Cutaneous Engineering and Biology Laboratory and IFR 133 Cell and Tissue Engineering and Biology, University of Franche-Comté, 25030, Besançon, France
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Oliveira GV, Chinkes D, Mitchell C, Oliveras G, Hawkins HK, Herndon DN. Objective assessment of burn scar vascularity, erythema, pliability, thickness, and planimetry. Dermatol Surg 2005; 31:48-58. [PMID: 15720096 DOI: 10.1111/j.1524-4725.2005.31004] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND There is currently a lack of objective methods to assess scars. OBJECTIVES The objectives of this study were to (1) determine the pattern of scar formation up to 24 months after a burn, compare clinical and photographic scar assessment, and determine what percentage of scars became hypertrophic after a major trauma and (2) replace each clinical parameter of a clinical scar scale by objective measurements. METHODS Scars from 62 patients were evaluated from the acute phase up to 24 months after the burn, using photographs and clinical assessment during visits. Photographic planimetry helped estimate the percentage of scars that became hypertrophic. Thereafter, 69 patients had scars evaluated using clinical assessment and several instruments to evaluate pigmentation, erythema, pliability, thickness, and perfusion. The sensitivity and specificity of each instrument were determined regarding their ability to correlate with the parameters of hypertrophic and nonhypertrophic scars. Analysis of variance and Tukey's test were used in statistical analysis, with p<.05 indicating significance. RESULTS Increased scar hypertrophy occurred between 6 and 12 months after the burn, and less than 30% of scars were hypertrophic at 18 to 24 months. Objective assessment of pliability and erythema, but not pigmentation, correlated significantly with clinical evaluation of hypertrophy. Hypertrophic scars had significantly higher perfusion than nonhypertrophic scars. A new scar rating system is proposed, based on the sensitivity and specificity of each instrument, to correlate with hypertrophic and nonhypertrophic scars. CONCLUSIONS Objective rating systems using reliable instruments can be used to replace subjective scar assessment. Larger multicenter prospective studies should test this new scale in scars due to other mechanisms of injury.
Collapse
Affiliation(s)
- Gisele V Oliveira
- Department of Surgery, Shriners Hospitals for Children and The University of Texas Medical Branch, Galveston, Texas 77550, USA
| | | | | | | | | | | |
Collapse
|
33
|
Crandall CG, Meyer DM, Davis SL, Dellaria SM. Palmar skin blood flow and temperature responses throughout endoscopic sympathectomy. Anesth Analg 2005; 100:277-283. [PMID: 15616091 DOI: 10.1213/01.ane.0000139359.46635.2d] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Thoracic surgical sympathectomy is often performed to treat primary palmar and axillary hyperhidrosis. An increase in palmar skin temperature is frequently used to identify the success of the procedure. Because changes in palmar skin temperature occur secondary to changes in skin blood flow, the objective of this study was to test the hypothesis that monitoring palmar skin blood flow would provide greater temporal resolution relative to monitoring palmar skin temperature. In 11 patients with palmar and/or axillary hyperhidrosis, we measured palmar skin temperature and blood flow (via laser Doppler flowmetry) throughout the sympathectomy procedure. Five minutes after the initial cautery, skin blood flow increased from 48 +/- 7 perfusion units to 121 +/- 17 perfusion units (P <0.001), whereas no significant change in temperature was observed (31.0 degrees C +/- 0.5 degrees C to 31.3 degrees C +/- 0.5 degrees C; P >0.05). The time required to reach peak skin blood flow (22 +/- 3 min) was significantly less than the time required to reach peak skin temperature (34 +/- 0.3 min; P <0.001). Finally at 5, 10, and 15 min after the initial cautery, skin blood flow increased to a larger percentage of the total increase in skin blood flow relative skin temperature (all P <0.006). These data suggest that monitoring skin blood flow provides greater temporal resolution when compared with monitoring skin temperature during thoracic sympathectomy. However, the initial cautery of the parietal pleura over the ganglion may result in increases in skin blood flow before physical disruption of the ganglion. This occurrence may limit the utility of skin blood-flow measurements in identifying the success of the procedure.
Collapse
Affiliation(s)
- Craig G Crandall
- *Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas, Texas; and Departments of †Internal Medicine, ‡Cardiothoracic Surgery, and §Anesthesiology and Pain Management, University of Texas Southwestern Medical Center at Dallas, Texas
| | | | | | | |
Collapse
|
34
|
Abstract
Optimal treatment of burn victims requires deep understanding of the profound pathophysiological changes occurring locally and systemically after injury. Accurate estimation of burn size and depth, as well as early resuscitation, is essential. Good burn care includes also cleansing, debridement, and prevention of sepsis. Wound healing, is of major importance to the survival and clinical outcome of burn patients. An ideal therapy would not only promote rapid healing but would also act as an antiscarring therapy. The present article is a literature review of the most up-to-date modalities applied to burn treatment without overlooking the numerous controversies that still persist.
Collapse
Affiliation(s)
- Bishara S Atiyeh
- Division of Plastic and Reconstructive Surgery, American University of Beirut Medical Center on Burns and Fire Disasters, Beirut, Lebanon.
| | | | | |
Collapse
|
35
|
Abstract
A number of noninvasive approaches have been developed over the years to provide objective evaluation of the skin both in health and in disease. The advent of computers, as well as of lasers and photonics, has made it possible to develop additional techniques that were impossible a few years ago. These approaches provide the dermatologist with sensitive tools to measure the skin's condition in terms of physiologic parameters (e.g., color, erythema and pigmentation, induration, sebaceous and stratum corneum lipids, barrier function, etc.). Yet, a typical dermatologic diagnosis relies primarily on the trained eyes of the physician and to a lesser extent on information from other senses, such as touch and smell. The trained senses of the dermatologist backed by his/her brain form a powerful set of tools for evaluating the skin. The golden rule in diagnosis remains the histologic examination of a skin biopsy, a rather invasive method. These tools have served the profession well. The advent of ever faster and cheaper computers and of sensitive, inexpensive optical instrumentation of minimal dimensions provides the professional with the possibility of making objective measures of a number of skin parameters.
Collapse
Affiliation(s)
- Nikiforos Kollias
- Johnson and Johnson Consumer Products Co., Skillman, New Jersey, USA
| | | |
Collapse
|
36
|
Langer S, Born F, Hatz R, Biberthaler P, Messmer K. Orthogonal polarization spectral imaging versus intravital fluorescent microscopy for microvascular studies in wounds. Ann Plast Surg 2002; 48:646-53. [PMID: 12055436 DOI: 10.1097/00000637-200206000-00014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The aim of this study was to validate orthogonal polarization spectral (OPS) imaging against intravital fluorescence microscopy (IFM) for microvascular measurements in normal skin and during wound healing. Experiments were performed on the ears of hairless mice (N = 8). The diameter of arterioles and venules, red blood cell velocity in venules, and the functional capillary density were assessed under normal conditions using OPS imaging and IFM. After creation of a circular wound, these observations were repeated at the identical microvascular regions on days 4, 7, 10, and 15. Images were videotaped, and CapImage was used for off-line computer-assisted analysis. Using OPS imaging, the microcirculation of wounded skin in hairless mice could be observed successfully. The regression analyses against standard IFM revealed a significant (p < 0.001) correlation for measurements of all microcirculatory parameters investigated (venular diameter: r(2) = 0.98, N = 345; red blood cell velocity: r(2) = 0.51, N = 326; functional capillary density: r(2) = 0.44, N = 156). However, for diameter as well as for functional capillary density measurements, OPS imaging yielded lower absolute values compared with IFM. The authors were able to validate OPS imaging against IFM for the measurement of microvascular parameters in an animal model of skin wound healing. Such a device should now help to study the role of microcirculation in physiology and pathophysiology during wound healing in patients. First clinical investigations are promising.
Collapse
Affiliation(s)
- S Langer
- Institute for Surgical Research, Department of Surgery, University Hospital Grosshadern, Ludwig-Maximilians University, Munich, Germany
| | | | | | | | | |
Collapse
|
37
|
Kloppenberg FW, Beerthuizen GI, ten Duis HJ. Perfusion of burn wounds assessed by Laser Doppler Imaging is related to burn depth and healing time. Burns 2001; 27:359-63. [PMID: 11348744 DOI: 10.1016/s0305-4179(00)00138-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Average perfusion in various burn wounds was assessed using Laser Doppler Imaging (LDI). The time necessary for a complete healing of the wound was compared to the results of the LDI measurements. A certain depth of burn was associated with a typical pattern of perfusion in the course of time. There was a significant difference between average perfusion in a full thickness burn requiring surgical treatment and burns with regenerative capacities.
Collapse
Affiliation(s)
- F W Kloppenberg
- Department of Surgery, Martini Hospital, PO Box 30033, 9700, Groningen, The Netherlands.
| | | | | |
Collapse
|
38
|
Ross D, Whitehead M, Pike B. Development and validation of an objective method of determining skin erythema to transdermal oestradiol patches. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1999; 106:279-83. [PMID: 10426650 DOI: 10.1111/j.1471-0528.1999.tb08244.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- D Ross
- Menopause Clinic, King's College Hospital, London, UK
| | | | | |
Collapse
|