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Sulfur mustard (SM) is an incapacitating chemical warfare agent used in numerous conflicts around the world and it is still a major threat for both, army troops and civilians. To evaluate its multiple targets effects in experimental setup, a model of whole body exposure (WBE) to SM vapor was established in rats and its simultaneous effects on lungs and eyes as well as on general wellbeing were examined. Rats were exposed to SM vapor. Evaluation (up to 10 weeks post-exposure) included body weight, general observation, blood counts and histological analysis. Results showed that following a latency-period of several hours, rats typical symptoms developed over a period of more than one week. The initial symptoms, characterized by swollen and erythematic nose, deteriorated into extensive rhinorrhea, eye closure, excessive lacrimation as well as rhonchi, wheezing and breathing difficulties. Alopecia and behavioral abnormality were also recorded. A weight loss of up to 40% was measured within one week with spontaneous recovery to baseline level within three weeks after exposure. Blood counts revealed leukopenia during the first three days post-exposure. Histological evaluation revealed a long lasting damage to the trachea, lungs and eyes. Thus, WBE to SM, was found to closely mimic the deleterious effects of SM on the sensitive tissues previously described in human victims during WWI and the Iran-Iraq war. The use of this animal model will enable comprehensive characterization of changes in biological processes that may lead to the development of therapeutic measures to ameliorate SM induced multi-system injuries. [ABSTRACT FROM AUTHOR]

Objective: Acrolein is a potent irritant and a vesicant that was used by the French during WWI as the warfare agent named: “papite”. Nowadays, it is produced in large amounts all over the world in the industry for the production of acrylic acid and for agriculture use as herbicide. The aim of this study was to characterize the effects of acute eye exposure to acrolein vapor and to evaluate the efficacy of a topical post-exposure combination treatment with a local anesthetic and a steroid. Methods: Rabbit eyes were exposed to three doses of acrolein vapor (low, intermediate and high) and treated topically with either 0.4% benoxinate hydrochloride (localin, for 2 h) or dexamethasone (dexamycin, for 6 days) or a combination of both drugs. Clinical follow-up using slit lamp examinations and histological evaluation was performed 4 weeks post-exposure. Results: Acrolein vapor caused immediate eye closure with excess tearing, corneal erosions and severe inflammation of the anterior chamber. This was followed by corneal neovascularization (NV) starting as early as 1 week post-exposure. The damage to the eyes was long lasting, and at 4 weeks following exposure, significant pathological changes were observed. Immediate post-exposure application of the local anesthetic, localin, prevented the eye closure, and the dexamycin treatment reduced significantly the initial inflammation as well as the extent and incidence of corneal NV. Conclusions: Short-term eye exposure to the irritant acrolein may result in immediate eye closure and long lasting pathologies that could lead to blindness. An anti-inflammatory treatment combined with short-term application of a local anesthetic prevents incapacitation and might minimize significantly the extent of eye injuries. [ABSTRACT FROM PUBLISHER]

Objective: Macrophages are known to have key functions in almost every stage of wound healing and there is evidence for their beneficial effects in treating decubital ulcers and deep sternal wound infections in human. This study aimed to investigate the efficacy of a treatment with activated macrophages on ameliorating acute and long-term sulfur mustard (SM) induced skin injuries in the hairless guinea pig (HGP) model. Methods: HGP were exposed to SM vapor and treated with either a single or multiple intra-dermal injections of human activated macrophages in suspension (hAMS) into the wound bed. Clinical and histological evaluations were conducted up to 4 weeks post-exposure. Results: A single treatment with hAMS early after exposure (15 min and 6 h) resulted in a reduction in the number of damaged cells and vesications in the epidermis at 24 h. A substantial increase in cellular infiltration, mostly polymorphonuclears, was taking place in the hAMS-treated animals starting as early as 1 h after exposure. This flow of inflammatory cells continued, in the treated group, for at least 4 weeks, long after the injected macrophages were not detected. Repeated injections of hAMS (15 min, 48 h and 7 d post-exposure) decreased significantly the area of the wounds and improved the integrity of the barrier function as expressed by measuring trans-epidermal water loss up to 10 d. Conclusions: Our results indicate that the role of macrophages in wound healing is complex; their efficacy may depend on the timing of administration. Further investigation is required to determine whether they are required during the early phase of wound development and/or during the late phase of scar formation and remodeling. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the involvement of VEGF in corneal neovascularization (CNV) following sulfur mustard (SM) exposure and to test the therapeutic effects of bevacizumab (Avastin) in respect to dose, route of administration and timing. Materials and methods: Topical bevacizumab (6 or 25 mg/ml, ×2/day) was applied to rabbit eyes, before or after appearance of NV, following SM vapor exposure, and was compared with subconjunctival injection (25 mg/ml, ×2/week) and topical dexamethasone (1%, ×4/day). Treatments were given for 3 weeks. VEGF levels were monitored by immunohistochemistry and ELISA assay. Clinical evaluations included slit-lamp examination, impression cytology for diagnosis of Limbal Stem Cell Deficiency (LSCD), pachymetry, measurement of NV length and histology. Results: Corneal NV was developed, as early as 2 weeks after exposure, in 50-70% of the eyes, associated with increased levels of VEGF. Topical bevacizumab treatment with both doses, starting at 4 weeks, reduced vascularization. Subconjunctival injection and topical dexamethasone were more potent. A combined treatment of dexamethasone and bevacizumab improved the anti-angiogenic efficacy, yet, there was no effect on LSCD. Topical bevacizumab treatment starting at 1 week, when VEGF was elevated but before appearance of NV, had no effect. Conclusions: VEGF was involved in corneal angiogenesis in SM-induced ocular injury. Bevacizumab was beneficial in reducing CNV by both, topical or subconjunctival injection, when given as a symptomatic therapy with or without dexamethasone, however with no effect on SC deficiency. Further studies on the pathological mechanism of SM-induced ocular surface disorder may direct towards improved therapy. [ABSTRACT FROM AUTHOR]