Social disparities and inequalities in healthcare access and expenditures among Iranians exposed to sulfur mustard: a national study using spatio-temporal analysis.

BACKGROUND: Sulfur Mustard (SM) is a chemical warfare agent that has serious short-term and long-term effects on health. Thousands of Iranians were exposed to SM during the eight-year Iran-Iraq conflict and permanently injured while the socioeconomic imbalance in their healthcare utilization (HCU) and health expenditures remains. This study aims to describe the HCU of SM-exposed survivors in Iran from 2018 to 2021; identify high-risk areas; and apply an inequality analysis of utilization regarding the socioeconomic groups to reduce the gap by controlling crucial determinants. METHODS: From Oct 2018 to June 2021, the Veterans and Martyrs Affairs Foundation (VMAF) recorded 58,888 living war survivors with eye, lung, and skin ailments. After cleaning the dataset and removing junk codes, we defined 11 HCU-related variables and predicted the HCU for the upcoming years using Bayesian spatio-temporal models. We explored the association of individual-level HCU and determinants using a Zero-inflated Poisson (ZIP) model and also investigated the provincial hotspots using Local Moran's I. RESULTS: With ≥ 90% confidence, we discovered eleven HCU clusters in Iran. We discovered that the expected number of HCU 1) rises with increasing age, severity of complications in survivors' eyes and lungs, wealth index (WI), life expectancy (LE), and hospital beds ratio; and 2) decreases with growing skin complications, years of schooling (YOS), urbanization, number of hospital beds, length of stay (LOS) in bed, and bed occupancy rate (BOR). The concentration index (CInd) of HCU and associated costs in age and wealth groups were all positive, however, the signs of CInd values for HCU and total cost in YOS, urbanization, LOS, and Hospital beds ratio groups were not identical. CONCLUSIONS: We observed a tendency of pro-rich inequity and also higher HCU and expenditures for the elderly population. Finally, health policies should tackle potential socioeconomic inequities to reduce HCU gaps in the SM-exposed population. Also, policymakers should allocate the resources according to the hotspots of HCU.

The impact of sulfur mustard on quality of life and mental health in Kurdish survivors in Sweden, thirty years after exposure.

BACKGROUND: The Iraqi state used chemical warfare agents (CWAs) like sulfur mustard (SM) in al-Anfal genocide in the present-day Kurdistan Region of Iraq. In addition to somatic injuries, exposure to CWAs causes biopsychosocial complications. We investigated the long-term impact of SM exposure on quality of life (QoL) and depression severity in Kurdish survivors resettled in Sweden. METHODS: This is a case-control study, where subjects exposed to SM (n = 18, mean age 51.3 years, 50% women) and sex- and age-matched nonexposed subjects (n = 30, mean age 48.7 years, 47% women) of Kurdish residents in Sweden. Data were collected through in-person interviews based on the RAND 36-item Short Form Health Survey to assess QoL and the Montgomery-Åsberg Depression Rating Scale-self assessment (MADRS-S) to investigate the presence and the gravity of depressive symptoms. RESULTS: The SM-exposed group had a significantly lower QoL than the nonexposed group (p < 0.001). Also, the overall mean MADRS-S scores among the SM-exposed group, corresponding to moderate depression, were higher than the scores of the nonexposed (22 points (p) vs. 9 p, p < .001). Overall, the participants within the exposed group reported worse mental than physical well-being 36p and 32p, respectively. Within the SM-exposed group, there was no gendered-related difference neither in terms of depression severity nor for QoL, but the groups were small. CONCLUSION: Individuals exposed to SM had worse QoL and a higher level of depressive severity compared with nonexposed individuals three decades after exposure, indicating the importance of increased clinician knowledge, guidelines, and an approach to assess and respond to the exposed groups' biopsychosocial needs. These findings indicate that those exposed to SM might need early identification of mental illnesses and more support to promote QoL.

Mortality rate of people exposed to Mustard Gas during Iran-Iraq war in Sardasht, Iran: a 32 years retrospective cohort study.

BACKGROUND: Mustard gas (MG) is one of the most widely used chemical weapons in the past century. However, little information exists concerning long-term mortality from MG exposure. In this study, we investigated mortality rate among civilian people exposed to MG during Iran-Iraq war in Sardasht in Iran after 32 years.  METHODS: In this retrospective cohort study, data of people exposed to MG in Sardasht in 1987 were extracted from the Veterans and Martyr Affair Foundation of Iran up to March 20, 2019. Mortality rate, cumulative mortality and standardized mortality ratio with 95% confidence interval were calculated to explain mortality in the cohort, and then compared with general Iranian population. Cox regression analysis was used to indicate factor affecting the risk of death in the cohort.  RESULTS: Out of 1,203 exposed people at the beginning of the period, 148 people died by the end of the study, with an average age of 66.42 at the time of death. Total person-years of the people up to end of the study were 38,198.63 and mortality rate was equal to 387 per 100,000 persons-years. Total number of observed deaths was less than expected death and the all-cause standardized mortality ratio (SMR) was determined as 0.680 (95% CI: 0.574 - 0.798). Cause-specific SMR showed that observed death due to respiratory diseases was higher than expected (SMR: 1.75) (95% CI: 1.145 - 2.569). The results of univariate and multivariate cox regression analysis showed that increasing age and having severe late complications in lung were associated with increased risk of death among people in the cohort. CONCLUSION: In general, this result indicated that acute exposure to MG, even without wearing protective clothing and masks, could not increase all-cause mortality after 32 years if accompanied by special and ongoing care for those exposed.

Exposure to sulfur mustard increases the risk for mortality in patients with COVID-19 infection: A cohort study.

OBJECTIVE: This study aims to assess the prognosis of inpatients with COVID-19 infection who have a history of sulfur mustard exposure. METHODS: We started a cohort study in October 2020 and ended in May 2021 on inpatients with COVID-19 infection who had been admitted to university healthcare centers. The analytic sample included 960 inpatients having COVID-19 infection (192 with; and 768 without sulfur mustard exposure). The exposed patients were male war veterans, and the unexposed patients were male individually age-matched people. All patients had a positive RT-PCR test and a positive chest CT for COVID-19. The outcome was death within 28 days of admission, and the predictors were clinical features recorded at patients' bedsides. RESULTS: There was a significantly higher prevalence for asthma (p = 0.026) and pulmonary disease other than asthma (p < 0.001) in patients with the exposure. Sulfur mustard exposure was associated with increased risk for mortality of COVID-19 [hazard ratio (95% CI) = 1.92 (1.14,3.24), p = 0.013]. Early intubation signified a poor prognosis [hazard = 7.34 (4.65,11.58), p < 0.001]. However, individuals with higher PaO2 [hazard = 0.97 (0.95,0.98), p < 0.001], or people undergoing O2 therapy early upon admission [hazard = 0.58 (0.38,0.89), p = 0.011] showed lower risks for mortality. Individuals with asthma were at higher risk for mortality [hazard = 3.76 (1.69,8.36), p = 0.001]. CONCLUSION: Individuals with COVID-19 infection and sulfur mustard exposure should be considered high-risk patients and that, healthcare settings should be ready to provide critical care for them, including O2 therapy. They are more likely to have asthma or other pulmonary diseases.

Glutathione conjugates of the mercapturic acid pathway and guanine adduct as biomarkers of exposure to CEES, a sulfur mustard analog.

Sulfur mustard (SM), a chemical warfare agent, is a strong alkylating compound that readily reacts with numerous biomolecules. The goal of the present work was to define and validate new biomarkers of exposure to SM that could be easily accessible in urine or plasma. Because investigations using SM are prohibited by the Organisation for the Prohibition of Chemical Weapons, we worked with 2-chloroethyl ethyl sulfide (CEES), a monofunctional analog of SM. We developed an ultra-high-pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) approach to the conjugate of CEES to glutathione and two of its metabolites: the cysteine and the N-acetylcysteine conjugates. The N7-guanine adduct of CEES (N7Gua-CEES) was also targeted. After synthesizing the specific biomarkers, a solid-phase extraction protocol and a UHPLC-MS/MS method with isotopic dilution were optimized. We were able to quantify N7Gua-CEES in the DNA of HaCaT keratinocytes and of explants of human skin exposed to CEES. N7Gua-CEES was also detected in the culture medium of these two models, together with the glutathione and the cysteine conjugates. In contrast, the N-acetylcysteine conjugate was not detected. The method was then applied to plasma from mice cutaneously exposed to CEES. All four markers could be detected. Our present results thus validate both the analytical technique and the biological relevance of new, easily quantifiable biomarkers of exposure to CEES. Because CEES behaves very similar to SM, the results are promising for application to this toxic of interest.

Identification of creatine kinase and alpha-1 antitrypsin as protein targets of alkylation by sulfur mustard.

Sulfur mustard (SM) is a toxic chemical warfare agent deployed in several conflicts within the last 100 years and still represents a threat in terroristic attacks and warfare. SM research focuses on understanding the pathophysiology of SM and identifying novel biomarkers of exposure. SM is known to alkylate nucleophilic moieties of endogenous proteins, for example, free thiol groups of cysteine residues. The two-dimensional-thiol-differences in gel electrophoresis (2D-thiol-DIGE) technique is an initial proteomics approach to detect proteins with free cysteine residues. These amino acids are selectively labeled with infrared-maleimide dyes visualized after GE. Cysteine residues derivatized by alkylating agents are no longer accessible for the maleimide-thiol coupling resulting in the loss of the fluorescent signal of the corresponding protein. To prove the applicability of 2D-thiol-DIGE, this technology was exemplarily applied to neat human serum albumin treated with SM, to lysates from human cell culture exposed to SM as well as to human plasma exposed to CEES (chloroethyl ethyl sulfide, an SM analogue). Exemplarily, the most prominent proteins modified by SM were identified by matrix-assisted laser desorption/ionization time-of-flight (tandem) mass spectrometry, MALDI-TOF MS(/MS), as creatine kinase (CK) from human cells and as alpha-1 antitrypsin (A1AT) from plasma samples. Peptides containing the residue Cys282 of CK and Cys232 of A1AT were unambiguously identified by micro liquid chromatography-electrospray ionization high-resolution tandem-mass spectrometry (µLC-ESI MS/HR MS) as being alkylated by SM bearing the specific hydroxyethylthioethyl-(HETE)-moiety. Both peptides might represent potential biomarkers of SM exposure. This is the first report introducing these endogenous proteins as targets of SM alkylation.

Debridement of Sulfur Mustard Skin Burns: A Comparison of Three Methods.

Sulfur mustard burns are characterized by delayed symptoms, slow healing, and recurrence after closure. Incomplete debridement at the level of the basement membrane is the postulated cause. Graham pioneered laser debridement of mustard burns. For field or mass-casualty use, saline wet-to-wet or antibiotic-soak debridement is more practical. In this study, we compared laser, saline, and antibiotic debridement in a porcine model of deep partial-thickness injury. Deep-dermal sulfur mustard burns were produced in 18 anesthetized Gottingen minipigs using 10-µl saturated vapor cap exposure time of 90 minutes. Debridement was started 48 hours postinjury and consisted of a single laser treatment; 5 days of 5% aqueous mafenide acetate wet-to-wet dressings; or 7 to 12 days of saline wet-to-wet dressings. Wounds were treated with daily silver sulfadiazine for 30 days and, then, assessed by histopathology, silver-ion analysis, colorimetry, and evaporimetry. All wounds healed well with no sign of infection. Antibiotic debridement showed no advantage over saline debridement. There were no significant differences between groups for colorimetry or evaporimetry. Histopathology was graded on a mustard-specific scale of 1 to 15 where higher values indicate better healing. Mean histology scores were 13.6 for laser, 13.9 for mafenide, and 14.3 for saline. Saline debridement statistically outperformed laser (P < .05) but required the longest debridement time. Laser debridement had the benefit of requiring a single treatment rather than daily dressing changes, significantly decreasing need for wound care and personnel resources. Development of a ruggedized laser for field use is a countermeasures priority.

Expression of miR-15b-5p, miR-21-5p, and SMAD7 in Lung Tissue of Sulfur Mustard-exposed Individuals with Long-term Pulmonary Complications.

Sulfur mustard (SM)-exposed individuals develop late pulmonary complications, which are associated with chronic inflammation and fibrotic changes in the lung tissue. MicroRNAs are known to act as important regulators of inflammatory responses, including inflammation and fibrosis-related cytokine signaling. In this study, we investigated the expression miR-15b-5p and miR-21-5p, two regulators of TGF-ß signaling, as well as their target molecule, SMAD7, in lung tissues from SM-exposed and control individuals. Total RNA was extracted from formalin-fixed paraffin-embedded (FFPE) lung tissue biopsies obtained during surgery from SM-exposed (n=20) or control (n=20) cases. Quality of the extracted RNA was evaluated by an Agilent Bioanalyzer and RNA was quantified using a NanoDrop. MiR-21-5p, miR-15b-5p and SMAD7 expression levels were measured by real-time RT-PCR. miR-21-5p expression levels were significantly decreased (2.7 fold) in the lung tissues from SM-exposed individuals compared with tissues obtained from the control group (p=0.02). There were no significant differences in miR-15b-5p expression levels between the two groups (p=0.94). Interestingly, SMAD7 expression levels were significantly higher (5.8 fold) in SM-exposed individuals' lung tissues compared with the control group (p=0.045). Our data indicate that exposure to sulfur mustard affects the expression of miR-21-5p as well as its target, SMAD7, in lung tissues many years after exposure. Considering the role of SMAD7 in the regulation of TGF-ß signaling, these changes might point to a potential mechanism by which SM-exposure regulates inflammatory/fibrotic alterations in lung tissue.

The study of genes and signal transduction pathways involved in mustard lung injury: A gene therapy approach.

Sulfur mustard (SM) is a destructive and harmful chemical agent for the eyes, skin and lungs that causes short-term and long-term lesions and was widely used in Iraq war against Iran (1980-1988). SM causes DNA damages, oxidative stress, and Inflammation. Considering the similarities between SM and COPD (Chronic Obstructive Pulmonary Disease) pathogens and limited available treatments, a novel therapeutic approach is not developed. Gene therapy is a novel therapeutic approach that uses genetic engineering science in treatment of most diseases including chronic obstructive pulmonary disease. In this review, attempts to presenting a comprehensive study of mustard lung and introducing the genes therapy involved in chronic obstructive pulmonary disease and emphasizing the pathways and genes involved in the pathology and pathogenesis of sulfur Mustard. It seems that, given the high potential of gene therapy and the fact that this experimental technique is a candidate for the treatment of pulmonary diseases, further study of genes, vectors and gene transfer systems can draw a very positive perspective of gene therapy in near future.

Is the Inflammasome Pathway Active in the Peripheral Blood of Sulfur Mustard-exposed Patients?

The mustard lung is a late consequence of exposure to sulfur mustard (SM) in veterans who had participated in the Iraq-Iran war. Three mechanisms are contributed in the pathogenesis of mustard lung including oxidative stress, protease-antiprotease imbalance, and dysregulated immune response. In the context of the immune response, the role of the inflammasome complex and their inflammatory cytokines are important. This study aims to investigate the inflammasome pathway and their inflammatory cytokine (i.e IL-1 and IL-18) in the peripheral blood of mustard lung patients as well as chronic obstructive pulmonary disease (COPD) patients. This research was conducted as a cross-sectional analytical study on 15 SM patients and was compared with 15 COPD patients and 15 healthy controls. The real-time polymerase chain reaction was used to assess gene expression levels of inflammasome components (NLRP1, NLRP3, NLRC4, and ASC), inflammatory cytokines (IL-1ß, IL-18, and IL-1ßR), and IL-37 as an anti-inflammatory cytokine. Finally, the data were analyzed by SPSS version 21 software. The gene expression level of molecules involved in inflammasome pathway showed a slight increase in the peripheral blood of SM and COPD patients compared to the control group. However, this difference was not statistically significant. Only IL-37 and NLRP1 had a significant increase in mustard lung and COPD patients; compared to healthy controls (p<0.05). Due to the normal expression of genes involved in the inflammasome pathway, it can be stated that the inflammasome pathway is not active in the blood of mustard lung patients.

The effect of carvacrol on inflammatory mediators and respiratory symptoms in veterans exposed to sulfur mustard, a randomized, placebo-controlled trial.

BACKGROUND: The aim of this study was to evaluate the effect of carvacrol on serum level of inflammatory mediators and respiratory symptoms in the veterans exposed to sulfur mustard (SM). METHODS: Twenty-one patients who were exposed to SM more than two decades' ago were divided to placebo and carvacrol (1.2 mg/kg/day) treated groups. Serum levels of Tumor Necrosis Factor-α (TNF-α), Monocyte chemotactic protein-1 (MCP-1), Vascular endothelial growth factor (VEGF), Epidermal growth factor (EGF), forced expiratory volume-one second (FEV1) and respiratory symptoms including; Chest wheeze (CW), night wheeze (NW), night cough (NC) and cough and wheeze during exercise (ECW) were assessed at the baseline (step 0), one and two months after starting treatment (step I and II, respectively). FINDINGS: FEV1 value was significantly increased in carvacrol treated group in step II compared to step 0 (p < 0.001) and also increased in step II compared to step I (p < 0.05). The respiratory symptoms including; CW and NW was significant decreased in carvacrol treated group in step I and II compared to step 0 (p < 0.01 to p < 0.001), NC and ECW were significantly decreased only in step II compared to step 0 (p < 0.01, for both cases). The serum levels of TNF-α, EGF and VEGF were decrease in carvacrol treated group in step I and II compared to step 0 (p < 0.05 to p < 0.001). The serum level of MCP-1 was decrease in carvacrol treated group only in the step II compared to step 0 (p < 0.05). INTERPRETATION: Two months' treatment with carvacrol reduced inflammatory cytokine and chemokine while increased anti-inflammatory cytokines and improved respiratory symptom and FEV1 value in SM exposed patients. CLINICAL TRIALS REGISTRY NUMBER: This trial was registered under IRCT2014031617020N1 at http://www.irct.ir/.

A comprehensive analysis of corneal mRNA levels during sulfur mustard induced ocular late pathology in the rabbit model using RNA sequencing.

Exposure to sulfur mustard (SM) may result in severe ocular injuries. While some of the eyes show a clinical resolution of the injury (defined as clinically non-impaired), part of the eyes develop irreversible late ocular pathologies (defined as clinically impaired) that may lead to corneal blindness. Understanding the pathological mechanisms underlying the development of the late pathology may lead to improved treatment options. Therefore, this study aimed to investigate the mRNA expression profiles of corneas from clinically impaired, clinically non-impaired and naïve eyes. Rabbit eyes were exposed to SM vapor and a clinical follow-up was carried out up to 4 weeks using a slit lamp microscope. At this time point, corneal tissues from clinically impaired, clinically non-impaired and naïve eyes were processed for RNA sequencing (RNA-seq) and differential expression analyses. The differential expression profiles were further subjected to pathway enrichment analysis using Ingenuity Pathway Analysis (IPA). Real-time PCR was used for RNA-seq validation. The late pathology developed in 54%-80% of the eyes following ocular exposure to SM, clinically manifested by inflammation, corneal opacity and neovascularization. RNA-seq results showed significant differences in mRNA levels of hundreds of genes between clinically impaired, clinically non-impaired and naïve corneas. Pathway enrichment analysis showed common pathways that were activated in all of the exposed eyes, such as Th1 and Th2 activation pathway, in addition to pathways that were activated only in the clinically impaired eyes compared to the clinically non-impaired eyes, such as IL-6 and ERK5 signaling. Corneal mRNA expression profiles for the clinically impaired, clinically non-impaired and naïve eyes generated a comprehensive database that revealed new factors and pathways, which for the first time were shown to be involved in SM-induced late pathology. Our data may contribute to the research on both the pathological mechanisms that are involved in the development of the late pathology and the protective pathways that are activated in the clinically non-impaired eyes and may point out towards novel therapeutic strategies for this severe ocular injury.

Relevance of Erk1/2-PI3K/Akt signaling pathway in CEES-induced oxidative stress regulates inflammation and apoptosis in keratinocytes.

2-Chloroethyl ethyl sulfide (CEES) is a well-known chemical warfare agent that induces cellular stress in exposed individuals. However, molecular mechanisms of CEES-induced oxidative stress-mediated metabolic deregulation are not clearly elucidated. Here we investigated CEES-induced free radical production act as key functional mediators of metabolic stress via Erk1/2 mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3-kinase (PI3K/Akt) signaling cascades in keratinocytes. We observed that CEES exposure disrupts the cellular antioxidant defense capacities leading to increase in free oxygen and nitrogen radical accumulation in keratinocytes. These unusual cellular abnormalities initiate cellular stress via Erk1/2-PI3K/Akt signaling pathways. Biochemical tools were used to analyze the changes in metabolites including sulfur amino acids (SAAs), namely, L-glutathione (GSH) and L-cysteine (Cys), in the presence of selective inhibitors of reactive oxygen/nitrogen species (ROS/RNS), Erk1/2, or PI3K/Akt after CEES exposure. Importantly, these metabolite changes were accompanied by a decrease in the glycolytic flux, consistent with the observed decrease in 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2) concentration and these CEES-induced phenomena were attenuated by pretreatment of Erk1/2 or PI3-K/Akt inhibitors. On the other hand, CEES exposure disrupts the protein carbonylation (PC) and lipid peroxidation (LPO) in keratinocytes leading to inflammation, crash of the cell-cell communication, cell cycle deregulation, and apoptosis via Erk1/2-PI3K/Akt pathways. However, pretreatment of Erk1/2 or PI3K/Akt inhibitors attenuated the CEES action. Collectively, these results illustrated that accumulated free radicals act as key functional mediators for inflammation, and apoptosis via Erk1/2-PI3K/Akt regulatory signaling cascades induced by CEES exposure. Treatment of pharmacological Erk1/2-PI3K/Akt inhibitors attenuated the CEES-induced keratinocyte injury that may provide the basis for the development of therapeutic strategy to work against CEES exposure.

Evaluation of the LTBP1 and Smad6 Genes Expression in Lung Tissue of Sulfur Mustard-exposed Individuals with Long-term Pulmonary Complications.

Sulfur mustard (SM) exposure injures different organs such as the lungs and leads to short and long term complications Transforming growth factor beta (TGF-ß) has the main role in altering fibroblast activities linked to airways remodeling. Latency TGF beta binding proteins 1 (LTBP1 facilitates localization of TGF-ß in the extracellular matrix. Mothers against decapentaplegic homolog 6 (Smad6) negatively regulates TGF-ß signaling, thus establishing a main negative feedback loop. In this study, we investigated the expression of LTBP1 and Smad6 in the lung tissues of SM-exposed and control individuals. Lung formalin-fixed paraffin-embedded (FFPE) blocks of SM-exposed (20 samples) and control groups (20 samples) were collected from archival pathology department of several general hospitals. The total mRNA of lung FFPE tissues was extracted. Quality of the extracted mRNA was evaluated by an Agilent Bio analyzer and RNA was quantified using a Nano Drop. LTBP1 and Smad6 expression levels were evaluated by real-time PCR. LTBP1 expression levels did not change between the two groups (p=0.626), howeverSmad6 expression levels were significantly higher (2.6 fold) in SM-exposed individuals compared to the control group (p=0.001). Our results revealed that Smad6 may be involved in lung tissue remodeling process in SM-exposed patients. Smad6 regulates fibrotic alterations in lung tissue and its function as negative feedback mechanisms in TGF-ß.

A Study of Corneal Biomechanics in Delayed-Onset Mustard Gas Keratopathy Compared to Cases With Corneal Scarring and Normal Corneas.

PURPOSE: This study compares the corneal biomechanical properties, as measured with Corvis ST, in three groups of cases with delayed-onset mustard gas keratopathy (DMGK), chronic corneal scarring (CCS), and those with normal corneas. METHODS: Forty-five eyes were enrolled in the DMGK, CCS, and normal groups (15 eyes each). All patients were examined with the slitlamp and Corvis ST. Extracted corneal biomechanical parameters included first and second applanation time (AT1, AT2), first and second applanation length (AL1, AL2), first and second applanation velocity (AV1, AV2), deformation amplitude (DA), highest concavity time, peak distance, highest concavity radius (HCR), central corneal thickness, corrected intraocular pressure (IOP), and noncorrected IOP. RESULTS: The mean age of the participants in the DMGK, CCS, and normal groups was 49.20±5.16, 60.40±22.92, and 44.60±8.32 years, respectively. Comparison between DMGK and CCS groups showed significant differences in AT1, AT2, corrected IOP, and noncorrected IOP. There were also significant differences in AT1, AT2, HCR, DA, and noncorrected IOP between the DMGK and normal groups. None of the parameters were significantly different between the CCS and normal groups. CONCLUSION: There seems to be reduced corneal rigidity and stiffness in cases exposed to mustard gas, which causes the cornea in the DMGK group to become applanated more easily and take longer to rebound compared with the other two groups. Also, IOP was lower than normal in the DMGK group, and thus, misdiagnosis of glaucoma is likely for these patients.

Evaluation of mRNA Expression Levels of TNFα, TNFR1 and IL1ß in Lung Tissue 20 Years after Sulfur-mustard Exposure.

Despite many years having passed since exposure to sulfur mustard (SM) gas, there are many exposed subjects who are still suffering from delayed pulmonary complications. The levels of pro-inflammatory cytokines in the lung of these subjects have not been investigated in delay phase. In this study, we evaluated mRNA expression of pro-inflammatory  cytokines (tumor necrosis factor alpha (TNFα), tumor necrosis factor receptor type 1 (TNFR1), and interleukin 1 beta (IL-1ß)  ) in lung biopsy of SM-exposed subjects and compared them with control (non-exposed) subjects. We used formalin-fixed, paraffin-embedded (FFPE) tissue for this purpose. Lung FFPE blocks of SM-exposed subjects (30 samples) and a control group (30 samples) were collected from archival pathology department. The total mRNA of FFPE tissues were extracted and the mRNA expression of pro-inflammatory  cytokines were determined by quantitative Real Time PCR (RT-qPCR). The obtained results from two groups were compared to each other and non-parametric statistical analyses were carried out on them. Our studies showed that the mRNA expression of TNFα, TNFR1 and IL-1ß  in lung tissue of SM injured and control people have no significant difference (p-value= 0.159, 0.832 and 0.314 respectivly). TNFR1 showed direct correlation with TNFα (r=0.867, p=0.002) and IL-1ß (r= 0.65, p=0.006). The evaluation of mRNA expression in pro-inflammatory cytokines in lung of SM-exposed subjects after 20 years showed that these mediators are similar to those of non-exposed group and there was no acute inflammation in lung of these patients.

Telomere shortening associated with increased levels of oxidative stress in sulfur mustard-exposed Iranian veterans.

Sulfur Mustard (SM) is the most widely used chemical weapon. It was used in World War 1 and in the more recent Iran-Iraq conflict. Genetic toxicity and DNA alkylation effects of SM in molecular and animal experiments are well documented. In this study, lymphocytic telomere lengths and serum levels of isoprostane F2α were measured using q-PCR and enzyme immunoassay-based methods in 40 Iranian veterans who had been exposed to SM between 1983-88 and 40 non-exposed healthy volunteers. The relative telomere length in SM-exposed individuals was found to be significantly shorter than the non-exposed individuals. In addition, the level of 8-isoprostane F2α was significantly higher in the SM-exposed group compared to controls. Oxidative stress can be caused by defective antioxidant responses following gene mutations or altered activities of antioxidant enzymes. Chronic respiratory diseases and infections may also increaseoxidative stress. The novel finding of this study was a the identification of 'premature ageing phenotype'. More specifically, telomere shortening which occurs naturally with aging is accelerated in SM-exposed individuals. Oxidative stress, mutations in DNA repair genes and epimutaions may be among the major mechanisms of telomere attrition. These findings may help for a novel therapeutic strategy by telomere elongation or for validation of an exposure biomarker for SM toxicity.

Sulfur Mustard-related Ocular Complications: A Review of Proteomic Alterations and Pathways Involved.

Sulphur mustard (SM; (2, 2'-dichloroethylsulfide)) was used for the first time in 1917, during the World War I. SM mainly induces DNA damage, oxidative stress, and inflammation. This compound injures the respiratory system, eyes, skin and the endocrine, gastrointestinal, and hematopoietic systems. However, due to the high lipophilicity of the SM and the lipophilic nature of the tear film, and also due to the direct contact of the eyes with the environment, the eyes are the most vulnerable part of the body to SM. SM causes several proteomic alterations in the eye. It increases the production and activity of inflammatory proteins, reduces the concentration of antioxidant proteins and activates the proteins involved in the onset of apoptosis. In this study, we reviewed SM-related proteomic alterations and the association of the found proteins with other eye disorders and diseases. Furthermore, using pathway enrichment analysis, we found the most central biological processes involved in the emergence of complications caused by SM. Our results revealed that deficient cellular homeostasis, especially in terms of iron-dependent regulations, as well as pathological changes in vascular endothelial growth factor (VEGF) expression, is the most central biological process involved in eye injuries caused by SM.

Chemical Contamination Transfer in the Management of War Casualties.

The use of chemical weapons agents (CWAs) was suspected in recent conflicts, during international conflicts, terrorist attacks, or civil wars. Little is known about the prevention needed for caregivers exposed to the risk of contamination transfer. We present a case of chemical contamination of health servicemembers during the management of casualties.

Free Radical Production and Oxidative Stress in Lung Tissue of Patients Exposed to Sulfur Mustard: An Overview of Cellular and Molecular Mechanisms.

Sulfur mustard (SM) is a chemical alkylating compound that primary targets lung tissue. It causes a wide variety of pathological effects in respiratory system such as chronic bronchitis, bronchiolitis obliterans, necrosis of the mucosa and inflammation, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis. However, molecular and cellular mechanisms for these pathologies are still unclear. Oxidative stress (OS) induced by reactive oxygen species (ROS) is likely a significant mechanism by which SM leads to cell death and tissues injury. SM can trigger various molecular and cellular pathways that are linked to ROS generation, OS, and inflammation. Hypoxia-induced oxidative stress, reduced activity of enzymatic antioxidants, depletion of intercellular glutathione (GSH), decreased productivity of GSH-dependent antioxidants, mitochondrial dysfunction, accumulation of leukocytes and proinflammatory cytokines, and increased expression of ROS producing-related enzymes and inflammatory mediators are the major events in which SM leads to massive production of ROS and OS in pulmonary system. Therefore, understanding of these molecules and signaling pathways gives us valuable information about toxicological effects of SM on injured tissues and the way for developing a suitable clinical treatment. In this review, we aim to discuss the possible mechanisms by which SM induces excessive production of ROS, OS, and antioxidants depletion in lung tissue of exposed patients.