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Skin decontamination procedures against potential hazards substances exposure. Chem Biol Interact 2021; 344:109481. [PMID: 34051209 DOI: 10.1016/j.cbi.2021.109481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/20/2021] [Accepted: 04/15/2021] [Indexed: 10/21/2022]
Abstract
Decontamination of unprotected skin areas is crucial to prevent excessive penetration of chemical contaminants after criminal or accidental release. A review of literature studies was performed to identify the available decontamination methods adopted to treat skin contamination after chemical, radiological and metal exposures. In this bibliographic review, an overview of the old and recent works on decontamination procedures followed in case of potential hazards substances contaminations with a comparison between these systems are provided. Almost all data from our 95 selected studies conducted in vitro and in vivo revealed that a rapid skin decontamination process is the most efficient way to reduce the risk of intoxication. The commonly-used or recommended conventional procedures are simple rinsing with water only or soapy water. However, this approach has some limitations because an easy removal by flushing may not be sufficient to decontaminate all chemical deposited on the skin, and skin absorption can be enhanced by the wash-in effect. Other liquid solutions or systems as adsorbent powders, mobilizing agents, chelation therapy are also applied as decontaminants, but till nowadays does not exist a decontamination method which can be adopted in all situations. Therefore, there is an urgent need to develop more efficient and successful decontaminating formulations.
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Etemad L, Moshiri M, Balali-Mood M. Advances in treatment of acute sulfur mustard poisoning - a critical review. Crit Rev Toxicol 2020; 49:191-214. [PMID: 31576778 DOI: 10.1080/10408444.2019.1579779] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Sulfur mustard (SM) is a blistering chemical warfare agent that was used during the World War I and in the Iraq-Iran conflict. The aim of this paper is to discuss and critically review the published results of experiments on the treatment of SM poisoning based on our clinical and research experience. The victims must remove from the contaminated zone immediately. The best solution for decontamination is large amounts of water, using neutral soap and 0.5% sodium hypochlorite. Severely intoxicated patients should be treated according to advanced life support protocols and intensive care therapy for respiratory disorders and the chemical burn. Sodium thiosulfate infusion (100-500 mg/kg/min) should be started up to 60 min after SM exposure. However, N-acetyle cysteine (NAC) is recommended, none of them acts as specific or effective antidote. The important protective and conservative treatment of SM-induced pulmonary injuries include humidified oxygen, bronchodilators, NAC as muculytic, rehydration, mechanical ventilation, appropriate antibiotics and respiratory physiotherapy as clinically indicated. Treatment of acute SM ocular lesions start with topical antibiotics; preferably sulfacetamide eye drop, continue with lubricants, and artificial tears. Treatment for cutaneous injuries include: moist dressing; preferably with silver sulfadiazine cream, analgesic, anti-pruritic, physically debridement, debridase, Laser debridement, followed by skin autologous split-thickness therapy as clinically indicated. The new suggested medications and therapeutic approaches include: anti-inflammatory agents, Niacinamide, Silibinin, Calmodulin antagonists, Clobetasol, full-thickness skin grafting for skin injuries; Doxycycline; Bevacizumab, and Colchicine for ocular injuries. Recommended compounds based on animal studies include Niacinamide, Aprotinin, des-aspartate-angiotensin-I, Gamma-glutamyltransferase, vitamin E, and vitamin D. In vitro studies revealed that Dimethylthiourea, L-nitroarginine, Methyl-ester, Sodium pyruvate, Butylated hydroxyanisole, ethacrynic acid, and macrolide antibiotics are effective. However, none of them, except macrolide antibiotics have been proved clinically. Avoidance of inappropriate polypharmacy is advisable.
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Affiliation(s)
- Leila Etemad
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences , Mashhad , Iran
| | - Mohammad Moshiri
- Medical Toxicology Research Center, Faculty of Medicine, Mashhad University of Medical Sciences , Mashhad , Iran
| | - Mahdi Balali-Mood
- Medical Toxicology and Drug Abuse Research Center, Birjand University of Medical Sciences , Birjand , Iran
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Lindsay CD, Timperley CM. TRPA1 and issues relating to animal model selection for extrapolating toxicity data to humans. Hum Exp Toxicol 2019; 39:14-36. [PMID: 31578097 DOI: 10.1177/0960327119877460] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The transient receptor potential ankyrin 1 (TRPA1) ion channel is a sensor for irritant chemicals, has ancient lineage, and is distributed across animal species including humans, where it features in many organs. Its activation by a diverse panel of electrophilic molecules (TRPA1 agonists) through electrostatic binding and/or covalent attachment to the protein causes the sensation of pain. This article reviews the species differences between TRPA1 channels and their responses, to assess the suitability of different animals to model the effects of TRPA1-activating electrophiles in humans, referring to common TRPA1 activators (exogenous and endogenous) and possible mechanisms of action relating to their toxicology. It concludes that close matching of in vitro and in vivo models will help optimise the identification of relevant biochemical and physiological responses to benchmark the efficacy of potential therapeutic drugs, including TRPA1 antagonists, to counter the toxic effects of those electrophiles capable of harming humans. The analysis of the species issue provided should aid the development of medical treatments to counter poisoning by such chemicals.
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Affiliation(s)
- C D Lindsay
- Chemical, Biological and Radiological (CBR) Division, Defence Science and Technology Laboratory (Dstl), Salisbury, UK
| | - C M Timperley
- Chemical, Biological and Radiological (CBR) Division, Defence Science and Technology Laboratory (Dstl), Salisbury, UK
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Casiraghi A, Ranzini F, Musazzi UM, Franzè S, Meloni M, Minghetti P. In vitro method to evaluate the barrier properties of medical devices for cutaneous use. Regul Toxicol Pharmacol 2017; 90:42-50. [DOI: 10.1016/j.yrtph.2017.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/05/2017] [Accepted: 08/14/2017] [Indexed: 10/19/2022]
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Bignon C, Amigoni S, Devers T, Guittard F. Barrier cream based on CeO 2 nanoparticles grafted polymer as an active compound against the penetration of organophosphates. Chem Biol Interact 2017; 267:17-24. [PMID: 26947807 DOI: 10.1016/j.cbi.2016.03.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 02/01/2016] [Accepted: 03/01/2016] [Indexed: 10/22/2022]
Abstract
Due to their small size, nanoparticles possess unique properties. Cerium oxide nanoparticles have been already studied for their capacity to adsorb and neutralize toxic compounds including organophosphates. By covalently grafting these nanoparticles to a thickening polymer, their potential aggregation resulting in a loss of surface area and their potential toxicity are avoided. Indeed, copolymers easily form gels in water at neutral pH thanks to low interactions occurring between polymeric chains; thus, gels can be spread on membrane supports to afford protective barriers. However, as we demonstrated previously, a formulation step of these hydride nanoparticle-polymeric compounds is necessary to overcome the cracking of the coating during drying. This work reports the impact of many factors on the efficiency of a new active Topical Skin Protectant (aTSP) including: (1) the presence of CeO2 nanoparticles in the protective coating and their amount, (2) their grafting to a perfluorocarbon thickening polymer and (3) the formulation of the CeO2 nanoparticle-grafted polymer. The combination of all the benefit parameters led to a very effective new aTSP against paraoxon penetration. The major in vitro diffusion studies were performed in Franz-type diffusion cells on two artificial membranes (silicone and Strat-M) and final validation on ex vivo human skin. The comparison of 24 h-exposure between membrane results indicated a difference in the behavior between the two artificial supports and the biological model; Strat-M membranes seeming closer to human skin results. Therefore, positive results regarding occlusive conditions should be confirmed with human skin.
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Affiliation(s)
- Cécile Bignon
- Université de Nice Sophia-Antipolis, Laboratoire de Physique de la Matière Condensée - UMR CNRS 7336, Groupe Surfaces et Interfaces, Parc Valrose, 06108 Nice Cedex 2, France
| | - Sonia Amigoni
- Université de Nice Sophia-Antipolis, Laboratoire de Physique de la Matière Condensée - UMR CNRS 7336, Groupe Surfaces et Interfaces, Parc Valrose, 06108 Nice Cedex 2, France.
| | - Thierry Devers
- ICMN UMR 7374, IUT de Chartres, Université d'Orléans, 21, rue de Loigny la Bataille, 28000 Chartres, France
| | - Frédéric Guittard
- Université de Nice Sophia-Antipolis, Laboratoire de Physique de la Matière Condensée - UMR CNRS 7336, Groupe Surfaces et Interfaces, Parc Valrose, 06108 Nice Cedex 2, France
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Mostosi C, Simonart T. Effectiveness of Barrier Creams against Irritant Contact Dermatitis. Dermatology 2016; 232:353-62. [DOI: 10.1159/000444219] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/15/2016] [Indexed: 11/19/2022] Open
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Chilcott RP, Larner J, Matar H, Kansagra S, Theivendran B, Viegas VA, Goldman VS. Optimisation of a dosing regime for a topical skin protectant (barrier cream). Cutan Ocul Toxicol 2015; 34:327-34. [DOI: 10.3109/15569527.2014.994124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Dalton CH, Hall CA, Lydon HL, Chipman JK, Graham JS, Jenner J, Chilcott RP. Development of haemostatic decontaminants for the treatment of wounds contaminated with chemical warfare agents. 2: Evaluation ofin vitrotopical decontamination efficacy using undamaged skin. J Appl Toxicol 2014; 35:543-50. [DOI: 10.1002/jat.3060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 07/09/2014] [Accepted: 07/10/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Christopher H. Dalton
- Biomedical Sciences; Dstl Porton Down; Salisbury SP4 0JQ UK
- School of Biosciences; University of Birmingham; Birmingham B15 2TT UK
| | - Charlotte A. Hall
- School of Biosciences; University of Birmingham; Birmingham B15 2TT UK
- Centre for Radiation, Chemical and Environmental Hazards; Health Protection Agency; Chilton Oxfordshire OX11 0JQ UK
| | - Helen L. Lydon
- School of Biosciences; University of Birmingham; Birmingham B15 2TT UK
- Centre for Radiation, Chemical and Environmental Hazards; Health Protection Agency; Chilton Oxfordshire OX11 0JQ UK
| | - J. K. Chipman
- School of Biosciences; University of Birmingham; Birmingham B15 2TT UK
| | - John S. Graham
- Medical Toxicology Branch, USAMRICD; Aberdeen Proving Ground; MD 21010-5400 USA
| | - John Jenner
- Biomedical Sciences; Dstl Porton Down; Salisbury SP4 0JQ UK
| | - Robert P. Chilcott
- Centre for Radiation, Chemical and Environmental Hazards; Health Protection Agency; Chilton Oxfordshire OX11 0JQ UK
- Research Centre for Transdermal Drug Delivery and Toxicology, Department of Pharmacy; University of Hertfordshire; Hatfield Herts AL10 9AB UK
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Mao C, Liu R, Bo L, Chen N, Li S, Xia S, Chen J, Li D, Zhang L, Xu Z. High-salt diets during pregnancy affected fetal and offspring renal renin-angiotensin system. J Endocrinol 2013; 218:61-73. [PMID: 23620529 PMCID: PMC4406098 DOI: 10.1530/joe-13-0139] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Intrauterine environments are related to fetal renal development and postnatal health. Influence of salty diets during pregnancy on renal functions and renin-angiotensin system (RAS) was determined in the ovine fetuses and offspring. Pregnant ewes were fed high-salt diet (HSD) or normal-salt diet (NSD) for 2 months during middle-to-late gestation. Fetal renal functions, plasma hormones, and mRNA and protein expressions of the key elements of renal RAS were measured in the fetuses and offspring. Fetal renal excretion of sodium was increased while urine volume decreased in the HSD group. Fetal blood urea nitrogen was increased, while kidney weight:body weight ratio decreased in the HSD group. The altered ratio was also observed in the offspring aged 15 and 90 days. Maternal and fetal plasma antidiuretic hormone was elevated without changes in plasma renin activity and Ang I levels, while plasma Ang II was decreased. The key elements of local renal RAS, including angiotensinogen, angiotensin converting enzyme (ACE), ACE2, AT1, and AT2 receptor expression in both mRNA and protein, except renin, were altered following maternal high salt intake. The results suggest that high intake of salt during pregnancy affected fetal renal development associated with an altered expression of the renal key elements of RAS, some alterations of fetal origins remained after birth as possible risks in developing renal or cardiovascular diseases.
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Affiliation(s)
- Caiping Mao
- Institute for Fetology and Reproductive Medicine Center, First Hospital of Soochow University, Suzhou 215006, People's Republic of China.
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Misik J, Pavlik M, Novotny L, Pavlikova R, Chilcott RP, Cabal J, Kuca K. In vivodecontamination of the nerve agent VX using the domestic swine model. Clin Toxicol (Phila) 2012; 50:807-11. [DOI: 10.3109/15563650.2012.720986] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Affiliation(s)
- Katherine Nolan
- Department of Dermatology; Mount Sinai School of Medicine; New York; New York
| | - Ellen Marmur
- Department of Dermatology; Mount Sinai School of Medicine; New York; New York
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Misík J, Pavlíková R, Cabal J, Novotný L, Kuča K. METHOD OF STATIC DIFFUSION CELLS FOR ASSESSMENT OF PESTICIDES SKIN PERMEATION. ACTA ACUST UNITED AC 2011. [DOI: 10.31482/mmsl.2011.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kehe K, Thiermann H, Balszuweit F, Eyer F, Steinritz D, Zilker T. Acute effects of sulfur mustard injury—Munich experiences. Toxicology 2009; 263:3-8. [DOI: 10.1016/j.tox.2009.04.060] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Revised: 04/20/2009] [Accepted: 04/21/2009] [Indexed: 10/20/2022]
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Millerioux J, Cruz C, Bazire A, Lallement G, Lefeuvre L, Josse D. In vitro selection and efficacy of topical skin protectants against the nerve agent VX. Toxicol In Vitro 2009; 23:539-45. [DOI: 10.1016/j.tiv.2009.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Millerioux J, Cruz C, Bazire A, Polly V, Lallement G, Lefeuvre L, Josse D. Evaluation of in vitro tests to assess the efficacy of formulations as topical skin protectants against organophosphorus compounds. Toxicol In Vitro 2009; 23:127-33. [DOI: 10.1016/j.tiv.2008.09.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 09/22/2008] [Accepted: 09/23/2008] [Indexed: 11/29/2022]
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Chilcott RP, Dalton CH, Ashley Z, Allen CE, Bradley ST, Maidment MP, Jenner J, Brown RFR, Gwyther RJ, Rice P. Evaluation of Barrier Creams Against Sulphur Mustard: (II)In VivoandIn VitroStudies using the Domestic White Pig. Cutan Ocul Toxicol 2008; 26:235-47. [PMID: 17687688 DOI: 10.1080/15569520701212373] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Previous studies in our laboratory have demonstrated that barrier creams, comprising perfluorinated polymers, are effective against the chemical warfare agent sulphur mustard (SM) when evaluated using human skin in vitro. The purpose of this follow-up study was to further evaluate three candidate (perfluorinated) barrier creams against SM (vapour) using the domestic white pig. The severity and progression of the resulting skin lesions were quantified daily for three weeks post-exposure using biophysical measurements of transepidermal water loss (TEWL) and skin reflectance spectroscopy (SRS). Skin biopsies obtained post-mortem were evaluated by light microscopy and additional skin samples were obtained from adjacent (unexposed) skin sites for a comparative in vitro skin absorption study. Samples of SM vapour within the dosing chambers were measured ex vivo to ascertain the exposure dose (Ct). The three creams were highly effective against SM in vivo (Ct approximately 5000 mg.min.m(-3)): After 3 weeks, barrier cream pre-treated sites were not significantly different from control (unexposed) skin when evaluated by TEWL, SRS or histology. In contrast, skin exposed to SM without pre-treatment showed evidence of persistent damage that was consistent with the slow healing time observed in humans. The amount of SM absorbed in vitro in untreated pig skin was similar to that required to cause comparable lesions in human skin (8-20 and 4-10 microg.cm(-2), respectively), further validating the use of pigs as a toxicologically-relevant dermal model for SM exposure.
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Affiliation(s)
- Robert P Chilcott
- Chemical Hazards and Poisons Division, Health Protection Agency, Chilton, Didcot, Oxfordshire, United Kingdom.
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Rieger T, Teichmann A, Richter H, Schanzer S, Sterry W, Lademann J. Evaluation of barrier creams ? introduction and comparison of 3 in vivo methods. Contact Dermatitis 2007; 56:347-54. [PMID: 17577377 DOI: 10.1111/j.1600-0536.2007.01125.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Often barrier creams (BC) do not fulfil their protecting behaviour, even when promised by the manufacturers. Therefore, it is of great importance to develop standardized in vivo techniques to prove the potency of BC in humans. In the present study, 3 promising techniques for the analysis of BC were evaluated: laser scanning microscopy, laser doppler flowmetry, and the tape-stripping procedure. Sodium fluorescein and glycerol trinitrate acted as hydrophilic model-penetrating substances. By means of these methods, 3 different BC were tested and compared for their potency. The investigations showed that primarily the tape-stripping procedure and also the laser scanning microscopy are promising tools for the evaluation of BC. In contrast, the laser doppler flowmetry represents a less feasible technique. In addition, the evaluation of BC showed that Vaseline enfolds a 100% barrier on the skin surface for the penetration of a hydrophilic dye, whereas BC1 only partially showed a protective effect and BC2 exhibited almost no potency. In conclusion, it can be referred that laser scanning microscopy and the tape-stripping procedure represent 2 non-invasive in vivo techniques, which enable a fast investigation concerning the potency of BC.
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Affiliation(s)
- Tina Rieger
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Charité- Universitätsmedizin Berlin, Berlin 10117, Germany
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Teichmann A, Jacobi U, Waibler E, Sterry W, Lademann J. An in vivo model to evaluate the efficacy of barrier creams on the level of skin penetration of chemicals. Contact Dermatitis 2006; 54:5-13. [PMID: 16426286 DOI: 10.1111/j.0105-1873.2006.00749.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reservoir function and the barrier function are important properties of the skin. The reservoir function is dependent on the barrier function which, however, needs support by protective measures, in particular under working conditions. Barrier creams represent a possibility to protect the skin. In the present study, a method was developed to investigate the effectiveness of reservoir closure by different formulations. Patent Blue V in water was used as a model penetrant. Its penetration, with and without barrier cream treatment, was analyzed by tape stripping in combination with UV/VIS spectroscopic measurements. The investigations showed that the stratum corneum represents a reservoir for topically applied Patent Blue V in water. Furthermore, the barrier investigations showed that vaseline and bees wax form a 100% barrier on the skin surface. The third barrier cream, containing waxes and surfactant, only partially showed a protective effect against the penetration of Patent Blue V in water. Strong interindividual differences were observed for this barrier product. In conclusion, it was assumed that the application of barrier creams cannot replace other protective measures and should be maximally used to inhibit low-grade irritants or in combination with other protectants or in body areas where other protective measures are not applicable.
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Affiliation(s)
- Alexa Teichmann
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Medical Faculty Charité, Schumannstr. 20/21, 10117 Berlin, Germany.
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Chilcott RP, Dalton CH, Hill I, Davison CM, Blohm KL, Clarkson ED, Hamilton MG. Evaluation of a Barrier Cream against the Chemical Warfare Agent VX using the Domestic White Pig. Basic Clin Pharmacol Toxicol 2005; 97:35-8. [PMID: 15943757 DOI: 10.1111/j.1742-7843.2005.pto_97106.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The purpose of this study was to evaluate the efficacy of a novel barrier cream formulation at reducing the percutaneous toxicity of a 2xLD(50) liquid challenge of nerve agent (VX). The study was conducted in vitro and in vivo using the domestic pig. Pretreatment of the (inner ear skin) exposure site with barrier cream eliminated mortality, reduced cholinesterase inhibition and prevented any physiological or biochemical signs of intoxication. In contrast, untreated animals exposed to VX exhibited severe signs of intoxication, near total AChE inhibition and generally died within the (3 hr) exposure period (5/6 animals). Application of the barrier cream caused a significant decrease in the area of skin contaminated by VX. It was tentatively concluded that spreading was predominantly a surface phenomena (possibly mediated by capillary movement of the agent through the microrelief or between hair follicles) with little or no contribution from lateral diffusion within the stratum corneum. There was a disparity between the in vitro and in vivo skin absorption measurements that was ascribed to the absence of systemic clearance in vitro. However, both models indicated a substantial reservoir of VX within the skin, providing a potential strategy for future investigations into "catch-up therapies". In summary, the novel barrier cream formulation was effective against a 2xLD(50) (liquid, percutaneous) dose of VX applied for 3 hr. Further work should be conducted to investigate more pragmatic issues such as optimal reapplication frequency and environmental effects such as temperature and humidity.
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Affiliation(s)
- Robert P Chilcott
- Chemical Hazards and Poisons Division, Health Protection Agency, Chilton, Didcot, Oxfordshire, OX11 0RQ, UK
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Lulich JP, Osborne CA, Sanderson SL. Effects of dietary supplementation with sodium chloride on urinary relative supersaturation with calcium oxalate in healthy dogs. Am J Vet Res 2005; 66:319-24. [PMID: 15757134 DOI: 10.2460/ajvr.2005.66.319] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the effect of dietary supplementation with sodium chloride (NaCl) on urinary calcium excretion, urine calcium concentration, and urinary relative supersaturation (RSS) with calcium oxalate (CaOx). ANIMALS 6 adult female healthy Beagles. PROCEDURE By use of a crossover study design, a canned diet designed to decrease CaOx urolith recurrence with and without supplemental NaCl (i.e., 1.2% and 0.24% sodium on a dry-matter basis, respectively) was fed to dogs for 6 weeks. Every 14 days, 24-hour urine samples were collected. Concentrations of lithogenic substances and urine pH were used to calculate values of urinary RSS with CaOx. RESULTS When dogs consumed a diet supplemented with NaCl, 24-hour urine volume and 24-hour urine calcium excretion increased. Dietary supplementation with NaCl was not associated with a change in urine calcium concentration. However, urine oxalate acid concentrations and values of urinary RSS with CaOx were significantly lower after feeding the NaCI-supplemented diet for 28 days. CONCLUSIONS AND CLINICAL RELEVANCE Dietary supplementation with NaCl in a urolith-prevention diet decreased the propensity for CaOx crystallization in the urine of healthy adult Beagles. However, until long-term studies evaluating the efficacy and safety of dietary supplementation with NaCl in dogs with CaOx urolithiasis are preformed, we suggest that dietary supplementation with NaCl be used cautiously.
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Affiliation(s)
- Jody P Lulich
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
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