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Perrone J, Haroz R, D'Orazio J, Gianotti G, Love J, Salzman M, Lowenstein M, Thakrar A, Klipp S, Rae L, Reed MK, Sisco E, Wightman R, Nelson LS. National Institute on Drug Abuse Clinical Trials Network Meeting Report: Managing Patients Exposed to Xylazine-Adulterated Opioids in Emergency, Hospital and Addiction Care Settings. Ann Emerg Med 2024; 84:20-28. [PMID: 38493376 DOI: 10.1016/j.annemergmed.2024.01.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 01/22/2024] [Accepted: 01/30/2024] [Indexed: 03/18/2024]
Abstract
Used as a veterinary sedative and not approved for human use, xylazine has been increasingly linked with opioid overdose deaths in the United States. A growing number of people have been exposed to xylazine in the illicit opioid supply (especially fentanyl) or in other drugs, particularly in some areas of the Northeast. Xylazine is an α-2 adrenergic agonist that decreases sympathetic nervous system activity. When combined with fentanyl or heroin, it is purported to extend the duration of the opioid's sedative effect and to cause dependence and an associated withdrawal syndrome; however, data to support these concerns are limited. Despite the escalating frequency of detection of xylazine in people with nonfatal and fatal opioid overdose, direct links to these outcomes have not been identified. Because the strongest causal link is to fentanyl coexposure, ventilatory support and naloxone remain the cornerstones of overdose management. Xylazine is also associated with severe tissue injury, including skin ulcers and tissue loss, but little is known about the underlying mechanisms. Nonetheless, strategies for prevention and treatment are emerging. The significance and clinical effects of xylazine as an adulterant is focused on 4 domains that merit further evaluation: fentanyl-xylazine overdose, xylazine dependence and withdrawal, xylazine-associated dermal manifestations, and xylazine surveillance and detection in clinical and nonclinical settings. This report reflects the Proceedings of the National Institute on Drug Abuse Center for the Clinical Trials Network convening of clinical and scientific experts, federal staff, and other stakeholders to describe emerging best practices for treating people exposed to xylazine-adulterated opioids. Participants identified scientific gaps and opportunities for research to inform clinical practice in emergency departments, hospitals, and addiction medicine settings.
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Affiliation(s)
- Jeanmarie Perrone
- Department of Emergency Medicine, Penn Center for Addiction Medicine and Policy, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA.
| | - Rachel Haroz
- Center for Healing, Cooper University Health Care, Cooper Medical School of Rowan University, Camden, NJ
| | - Joseph D'Orazio
- Center for Healing, Cooper University Health Care, Cooper Medical School of Rowan University, Camden, NJ
| | - Giacomo Gianotti
- University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA
| | - Jennifer Love
- Icahn School of Medicine at Mount Sinai, New York, NY
| | - Matthew Salzman
- Department of Emergency Medicine, Cooper Medical School of Rowan University, Camden, NJ
| | - Margaret Lowenstein
- Division of General Internal Medicine, Penn Center for Addiction Medicine and Policy, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
| | - Ashish Thakrar
- Division of General Internal Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
| | | | - Lisa Rae
- Lewis Katz School of Medicine, Temple University, Philadelphia, PA
| | - Megan K Reed
- Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA
| | - Edward Sisco
- National Institute of Standards and Technology, Gaithersburg, MD
| | - Rachel Wightman
- Department of Emergency Medicine, Alpert Medical School of Brown University, Providence, RI
| | - Lewis S Nelson
- Department of Emergency Medicine, Rutgers New Jersey Medical School, Newark, NJ
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D'Orazio J, Nelson L, Perrone J, Wightman R, Haroz R. Xylazine Adulteration of the Heroin-Fentanyl Drug Supply : A Narrative Review. Ann Intern Med 2023; 176:1370-1376. [PMID: 37812779 DOI: 10.7326/m23-2001] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/11/2023] Open
Abstract
Xylazine is an animal sedative, approved by the U.S. Food and Drug Administration, that is commonly used in veterinary medicine and is not approved for human use. Since 2016, xylazine has consistently appeared in the illicitly manufactured fentanyl supply and has significantly increased in prevalence, likely due to its low cost, easy availability, and presumed synergistic psychoactive effect. Clinical experience along with the available pertinent research were used to review xylazine adulteration of the drug supply and provide guidance on the care of patients exposed to xylazine. This review discusses xylazine pharmacology, animal and human clinical effects, and what is known to date about care of patients experiencing acute overdose, xylazine-fentanyl withdrawal, and xylazine-associated wounds.
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Affiliation(s)
- Joseph D'Orazio
- Cooper University Healthcare, Camden, New Jersey (J.D., R.H.)
| | - Lewis Nelson
- Rutgers New Jersey Medical School, Newark, New Jersey (L.N.)
| | | | - Rachel Wightman
- Alpert Medical School of Brown University, Providence, Rhode Island (R.W.)
| | - Rachel Haroz
- Cooper University Healthcare, Camden, New Jersey (J.D., R.H.)
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Effects of Anesthetics on Barrier Tissue Function. J Immunol Res 2019; 2019:5920620. [PMID: 31772948 PMCID: PMC6854914 DOI: 10.1155/2019/5920620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 08/22/2019] [Indexed: 11/30/2022] Open
Abstract
Anesthetics have long been proven to have additional effects other than anesthesia on different organs and tissues of the human body. Barrier tissues play critical roles in human health and diseases, yet the impacts of anesthetics on barrier tissues are still not clear. This review article is aimed at summarizing different effects of anesthetics on the skin, the respiratory, and intestinal membranes from two aspects: inflammation/immunity and ischemia-reperfusion. Among volatile, intravenous, and local anesthetics, volatile anesthetics are less influential on barrier ischemia-perfusion function. Although direct comparisons between volatile and the other two types of anesthetics are still lacking, volatile anesthetics appear to have stronger anti-inflammatory effects on different barrier tissues through various mechanisms. These results suggested that when treating patients with barrier tissue complications, volatile anesthetics can provide better therapeutic outcomes.
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Gallez B. Contribution of Harold M. Swartz to In Vivo EPR and EPR Dosimetry. RADIATION PROTECTION DOSIMETRY 2016; 172:16-37. [PMID: 27421469 DOI: 10.1093/rpd/ncw157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In 2015, we are celebrating half a century of research in the application of Electron Paramagnetic Resonance (EPR) as a biodosimetry tool to evaluate the dose received by irradiated people. During the EPR Biodose 2015 meeting, a special session was organized to acknowledge the pioneering contribution of Harold M. (Hal) Swartz in the field. The article summarizes his main contribution in physiology and medicine. Four emerging themes have been pursued continuously along his career since its beginning: (1) radiation biology; (2) oxygen and oxidation; (3) measuring physiology in vivo; and (4) application of these measurements in clinical medicine. The common feature among all these different subjects has been the use of magnetic resonance techniques, especially EPR. In this article, you will find an impressionist portrait of Hal Swartz with the description of the 'making of' this pioneer, a time-line perspective on his career with the creation of three National Institutes of Health-funded EPR centers, a topic-oriented perspective on his career with a description of his major contributions to Science, his role as a mentor and his influence on his academic children, his active role as founder of scientific societies and organizer of scientific meetings, and the well-deserved international recognition received so far.
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Affiliation(s)
- Bernard Gallez
- Université Catholique de Louvain, Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, Avenue Mounier 73.08, B-1200, Brussels, Belgium
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Desmet CM, Lafosse A, Vériter S, Porporato PE, Sonveaux P, Dufrane D, Levêque P, Gallez B. Application of Electron Paramagnetic Resonance (EPR) Oximetry to Monitor Oxygen in Wounds in Diabetic Models. PLoS One 2015; 10:e0144914. [PMID: 26659378 PMCID: PMC4679295 DOI: 10.1371/journal.pone.0144914] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 11/26/2015] [Indexed: 11/18/2022] Open
Abstract
A lack of oxygen is classically described as a major cause of impaired wound healing in diabetic patients. Even if the role of oxygen in the wound healing process is well recognized, measurement of oxygen levels in a wound remains challenging. The purpose of the present study was to assess the value of electron paramagnetic resonance (EPR) oximetry to monitor pO2 in wounds during the healing process in diabetic mouse models. Kinetics of wound closure were carried out in streptozotocin (STZ)-treated and db/db mice. The pO2 was followed repeatedly during the healing process by 1 GHz EPR spectroscopy with lithium phthalocyanine (LiPc) crystals used as oxygen sensor in two different wound models: a full-thickness excisional skin wound and a pedicled skin flap. Wound closure kinetics were dramatically slower in 12-week-old db/db compared to control (db/+) mice, whereas kinetics were not statistically different in STZ-treated compared to control mice. At the center of excisional wounds, measurements were highly influenced by atmospheric oxygen early in the healing process. In pedicled flaps, hypoxia was observed early after wounding. While reoxygenation occurred over time in db/+ mice, hypoxia was prolonged in the diabetic db/db model. This observation was consistent with impaired healing and microangiopathies observed using intravital microscopy. In conclusion, EPR oximetry using LiPc crystals as the oxygen sensor is an appropriate technique to follow wound oxygenation in acute and chronic wounds, in normal and diabetic animals. Nevertheless, the technique is limited for measurements in pedicled skin flaps and cannot be applied to excisional wounds in which diffusion of atmospheric oxygen significantly affects the measurements.
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Affiliation(s)
- Céline M. Desmet
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Brussels, Belgium
| | - Aurore Lafosse
- Endocrine Cell Therapy Unit, Center of Tissue/Cell Therapy, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
- Plastic and Reconstructive Surgery Unit, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Sophie Vériter
- Endocrine Cell Therapy Unit, Center of Tissue/Cell Therapy, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Paolo E. Porporato
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Pierre Sonveaux
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Denis Dufrane
- Endocrine Cell Therapy Unit, Center of Tissue/Cell Therapy, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Philippe Levêque
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Brussels, Belgium
| | - Bernard Gallez
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Brussels, Belgium
- * E-mail:
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Mahling M, Fuchs K, Thaiss WM, Maier FC, Feger M, Bukala D, Harant M, Eichner M, Reutershan J, Lang F, Reischl G, Pichler BJ, Kneilling M. A Comparative pO2 Probe and [18F]-Fluoro-Azomycinarabino-Furanoside ([18F]FAZA) PET Study Reveals Anesthesia-Induced Impairment of Oxygenation and Perfusion in Tumor and Muscle. PLoS One 2015; 10:e0124665. [PMID: 25902054 PMCID: PMC4406741 DOI: 10.1371/journal.pone.0124665] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 03/17/2015] [Indexed: 11/18/2022] Open
Abstract
Tumor hypoxia can be identified by [18F]FAZA positron emission tomography, or invasively using oxygen probes. The impact of anesthetics on tumor hypoxia remains controversial. The aim of this comprehensive study was to investigate the impact of isoflurane and ketamine/xylazine anesthesia on [18F]FAZA uptake and partial oxygen pressure (pO2) in carcinoma and muscle tissue of air- and oxygen-breathing mice.
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Affiliation(s)
- Moritz Mahling
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
- * E-mail: (BJP); (MM)
| | - Kerstin Fuchs
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
- Department of Dermatology, Eberhard Karls University Tübingen, Liebermeisterstraße 25, 72076 Tübingen, Germany
| | - Wolfgang M. Thaiss
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
- Department of Radiology, Eberhard Karls University Tübingen, Hoppe-Seyler-Straße 3, 72076 Tübingen, Germany
| | - Florian C. Maier
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
| | - Martina Feger
- Department of Physiology, Eberhard Karls University Tübingen, Gmelinstrasse 5, 72076 Tübingen, Germany
| | - Daniel Bukala
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
| | - Maren Harant
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
| | - Martin Eichner
- Institute for Clinical Epidemiology and Applied Biometry, Eberhard Karls University Tübingen, Silcherstraße 5, 72076 Tübingen, Germany
| | - Jörg Reutershan
- Department of Anesthesiology and Intensive Care Medicine, Eberhard Karls University Tübingen, Hoppe-Seyler-Straße 3, 72076 Tübingen, Germany
| | - Florian Lang
- Department of Physiology, Eberhard Karls University Tübingen, Gmelinstrasse 5, 72076 Tübingen, Germany
| | - Gerald Reischl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
| | - Bernd J. Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
- * E-mail: (BJP); (MM)
| | - Manfred Kneilling
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Röntgenweg 13, 72076 Tübingen, Germany
- Department of Dermatology, Eberhard Karls University Tübingen, Liebermeisterstraße 25, 72076 Tübingen, Germany
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Reyes JC, Negrón JL, Colón HM, Padilla AM, Millán MY, Matos TD, Robles RR. The emerging of xylazine as a new drug of abuse and its health consequences among drug users in Puerto Rico. J Urban Health 2012; 89:519-26. [PMID: 22391983 PMCID: PMC3368046 DOI: 10.1007/s11524-011-9662-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
During the last decade, the veterinary anesthetics have gained popularity as recreational drugs. The aim of this study was to document the use of "anestecia de caballo" (xylazine) and its consequences among drug users in Puerto Rico. The study combined a cross-sectional survey with 89 drug users and two focus groups conducted in Mayagüez with frontline drug treatment providers. Drug users were recruited from communities of the San Juan metropolitan area using a variety of ethnographic and outreach strategies. A short questionnaire developed for the study collected information on sociodemographics, xylazine use, and its consequences. The two focus groups were conducted to discuss the details related to xylazine use, its consequences, and utilization awareness. The sample comprised 63 males (70.8%) and 26 females with a mean age of 37.2 years. The mean number of years of drug use was 14.3, with a mean frequency of drug use of 5.9 times daily. More than 65% reported speedball as the principal drug of use. The prevalence of xylazine use was 80.7%. More than 42% of the sample used xylazine in a mixture with speedball. The main route of administration of xylazine was injection but 14% reported the use of xylazine by inhalation. More than 35% of the sample reported skin lesions and 21.1% reported at least one overdose episode. Multiple logistic regression analysis revealed that males (OR = 3.47, CI = 1.10-12.00) and those who reported speedball as their main drug of use (OR = 9.34, CI = 2.51-34.70) were significantly more likely to be xylazine users. Focus groups revealed that drug users claimed to recognize the presence of xylaxine in a mixture of speedball based on its effects, taste, the color of the drug (dark brown), and its odor. In conclusion, the use of xylazine among drug users in Puerto Rico seems to be an emerging trend with potentially serious health consequences.
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Affiliation(s)
- J C Reyes
- Medical Science Campus Universidad de Puerto Rico, San Juan, Puerto Rico.
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Palero JA, Bader AN, de Bruijn HS, der Ploeg van den Heuvel AV, Sterenborg HJCM, Gerritsen HC. In vivo monitoring of protein-bound and free NADH during ischemia by nonlinear spectral imaging microscopy. BIOMEDICAL OPTICS EXPRESS 2011; 2:1030-9. [PMID: 21559117 PMCID: PMC3087562 DOI: 10.1364/boe.2.001030] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 03/19/2011] [Accepted: 03/29/2011] [Indexed: 05/20/2023]
Abstract
Nonlinear spectral imaging microscopy (NSIM) allows simultaneous morphological and spectroscopic investigation of intercellular events within living animals. In this study we used NSIM for in vivo time-lapse in-depth spectral imaging and monitoring of protein-bound and free reduced nicotinamide adenine dinucleotide (NADH) in mouse keratinocytes following total acute ischemia for 3.3 h at ~3 min time intervals. The high spectral resolution of NSIM images allows discrimination between the two-photon excited fluorescence emission of protein-bound and free NAD(P)H by applying linear spectral unmixing to the spectral image data. Results reveal the difference in the dynamic response between protein-bound and free NAD(P)H to ischemia-induced hypoxia/anoxia. Our results demonstrate the capability of nonlinear spectral imaging microscopy in unraveling dynamic cellular metabolic events within living animals for long periods of time.
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Affiliation(s)
- Jonathan A. Palero
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
- Currently with ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain
| | - Arjen N. Bader
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Henriëtte S. de Bruijn
- Department of Radiation Oncology,Center of Optical Diagnostics and Therapy, Erasmus Medical Center,3008 AE Rotterdam, The Netherlands
| | | | - Henricus J. C. M. Sterenborg
- Department of Radiation Oncology,Center of Optical Diagnostics and Therapy, Erasmus Medical Center,3008 AE Rotterdam, The Netherlands
| | - Hans C. Gerritsen
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
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He JW, Kashyap D, Trevino LA, Liu H, Peng YB. Simultaneous absolute measures of glabrous skin hemodynamic and light-scattering change in response to formalin injection in rats. Neurosci Lett 2011; 492:59-63. [PMID: 21281696 DOI: 10.1016/j.neulet.2011.01.057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 01/21/2011] [Accepted: 01/23/2011] [Indexed: 12/20/2022]
Abstract
Subcutaneous injection of formalin is a well-known model to study the nature of inflammatory pain. One of the cardinal signs of inflammation is redness, as a result of increased blood perfusion. We used an optical technology, light reflectance spectroscopy, to noninvasively obtain absolute measures of cutaneous hemodynamic components, including the concentrations of oxy- ([HbO]), deoxy- ([Hb]), total-hemoglobin ([HbT]), oxygen saturation (SO(2)), and the reduced light-scattering coefficient (μs'). The objective is to assess the effect of formalin-induced skin inflammation on the aforementioned parameters. Six rats were injected with formalin (50 μl, 3%) into left hind paw under pentobarbital anesthesia. Our results indicate prolonged increases in [HbO], [HbT], and SO(2) post injection only in the ipsilateral side. No statistically significant changes in [Hb] and μ(s)' occurred in either side. The arterial blood influx tends to be the major attribute of local hyperemia during inflammation. Thereby, [HbO] appears to be superior to [Hb] in measuring inflammation. In conclusion, the needle-probe-based light reflectance can be a feasible means to obtaining absolute measures of skin hemodynamic and light-scattering parameters when studying inflammatory pain.
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Affiliation(s)
- Ji-Wei He
- Department of Psychology, College of Science, University of Texas at Arlington, Arlington, TX 76019-0528, USA
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Schlosser S, Spanholtz T, Merz K, Dennler C, Banic A, Erni D, Plock JA. The Choice of Anesthesia Influences Oxidative Energy Metabolism and Tissue Survival in Critically Ischemic Murine Skin. J Surg Res 2010; 162:308-13. [DOI: 10.1016/j.jss.2009.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Revised: 03/04/2009] [Accepted: 03/06/2009] [Indexed: 10/20/2022]
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Abstract
The technique of electron paramagnetic resonance (EPR) spectroscopy is more than 50 years old, but only recently it has been used for in vivo studies. Its limited application in the past was due to the problem of high nonresonant dielectric loss of the exciting frequency because of high water content in biological samples. However, with the development of spectrometers working at lower frequencies (1,200 MHz and below) during the last 15 years, it is now possible to conduct in vivo measurements on a variety of animals and isolated organs. This is further facilitated by the development of new resonators with high sensitivity and appropriate stability for in vivo applications. It now has become feasible to obtain new insights into the complex aspects of physiology and pathophysiology using in vivo EPR. Among several important applications of this technique, the in vivo tissue pO(2) (partial pressure of oxygen) and redox measurements seem to be the most extensive use of this technique. In this chapter, we describe the procedure for in vivo pO(2) and redox measurements in animal models.
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Abstract
Electron paramagnetic resonance (EPR) spectroscopy and imaging (EPRI) are deeply rooted in the basic and quantum physics, but the spectrum of their applications in modern experimental and clinical dermatology and cosmetology is surprisingly wide. The main aim of this review was to show the physical foundation, technical limitations and versatility of this method in skin studies. Free radical and metal ion detection, EPR dosimetry, melanin study, spin trapping, spin labelling, oximetry and NO-metry, EPR imaging, new generation methods of EPR and EPR/NMR hybrid technology used under ex vivo and in vivo regime are portrayed in the context of clinical and experimental skin research to study problems such as oxidative and nitrosative stress generated by UV or inflammation, skin oxygenation, hydration of corneal layer of epidermis, transport and metabolism of drugs and cosmeceutics, skin carcinogenesis, skin tumors and many others. A part of the paper is devoted to hair and nail research. The review of dermatological applications of EPR is supplemented with a handful of advice concerning practical aspects of EPR experimentation and usage of EPR reagents.
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Affiliation(s)
- Przemyslaw M Plonka
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
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Abramović Z, Šuštaršič U, Teskač K, Šentjurc M, Kristl J. Influence of nanosized delivery systems with benzyl nicotinate and penetration enhancers on skin oxygenation. Int J Pharm 2008; 359:220-7. [DOI: 10.1016/j.ijpharm.2008.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/10/2008] [Accepted: 03/12/2008] [Indexed: 11/24/2022]
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Khan N, Williams BB, Hou H, Li H, Swartz HM. Repetitive tissue pO2 measurements by electron paramagnetic resonance oximetry: current status and future potential for experimental and clinical studies. Antioxid Redox Signal 2007; 9:1169-82. [PMID: 17536960 PMCID: PMC2921178 DOI: 10.1089/ars.2007.1635] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Tissue oxygen plays a crucial role in maintaining tissue viability and in various diseases, including responses to therapy. Useful knowledge has been gained by methods that can give limited snapshots of tissue oxygen (e.g., oxygen electrodes) or evidence of a history of tissue hypoxia (e.g., EF5) or even indirect evidence by monitoring oxygen availability in the circulatory system (e.g., NMR methods). Each of these methods has advantages and significant limitations. EPR oximetry is a technique for direct measurement of tissue pO2, which has several advantages over the other existing methods for applications in which the parameter of interest is the pO2 of tissues, and information is needed over a time course of minutes to hours, and/or for repetitive measurements over days or weeks or years. The aim of this article is to provide an overview of EPR oximetry using particulates to readers who are not familiar with this technique and its potential in vivo and clinical applications. The data presented here are from the experiments currently being carried out in our laboratory. We are confident that in vivo EPR oximetry will play a crucial role in the understanding and clinical management of various pathologies in the years to come.
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Affiliation(s)
- Nadeem Khan
- EPR Center for Viable Systems, Dartmouth Medical School, Hanover, New Hampshire 03755, USA
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