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.

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.

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 S419 on human serum albumin as a novel biomarker for sarin and cyclosarin exposure.

RATIONALE: Organophosphorus nerve agents are highly toxic because they inhibit acetylcholinesterase activity, thereby causing a series of symptomatic poisoning. Upon entering the body, nerve agents bind active amino acid residues to form phosphonylated adducts. A potentially beneficial method for specific verification of exposure of nerve agents is based on albumin adducts, which have a half-life of 18 days. This appears to be more effective than the fluoride reactivation method, based on acetylcholinesterase. METHODS: After the exposure of human serum albumin to nine nerve agents, human serum albumin was denatured, reduced, alkylated and digested with trypsin according to standard mass spectrometry-based proteomics procedures. The phosphonylated peptides of human serum albumin were identified using positive ion electrospray ionization with a quadrupole orbitrap mass spectrometer. RESULTS: The peptide KVPQVSTPTLVESR showed a good mass spectrometric response to the nine nerve agents. The tendency of sarin and cyclosarin was to bind to S419 on the peptide, while the other nerve agents (tabun, soman and V-type nerve agents) were shown to bind more readily to K414 on the peptide. CONCLUSIONS: This research revealed a new site, S419, of the tryptic peptide KVPQVSTPTLVEVSR on human albumin to be a valuable biomarker for sarin/cyclosarin exposure, helping to further distinguish sarin and cyclosarin poisoning from that of other nerve agents and providing an important tool for the identification of sarin or cyclosarin in terrorist attacks.

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.

Cutaneous exposure to lewisite causes acute kidney injury by invoking DNA damage and autophagic response.

Lewisite (2-chlorovinyldichloroarsine) is an organic arsenical chemical warfare agent that was developed and weaponized during World Wars I/II. Stockpiles of lewisite still exist in many parts of the world and pose potential environmental and human health threat. Exposure to lewisite and similar chemicals causes intense cutaneous inflammatory response. However, morbidity and mortality in the exposed population is not only the result of cutaneous damage but is also a result of systemic injury. Here, we provide data delineating the pathogenesis of acute kidney injury (AKI) following cutaneous exposure to lewisite and its analog phenylarsine oxide (PAO) in a murine model. Both agents caused renal tubular injury, characterized by loss of brush border in proximal tubules and tubular cell apoptosis accompanied by increases in serum creatinine, neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1. Interestingly, lewisite exposure enhanced production of reactive oxygen species (ROS) in the kidney and resulted in the activation of autophagic and DNA damage response (DDR) signaling pathways with increased expression of beclin-1, autophagy-related gene 7, and LC-3A/B-II and increased phosphorylation of γ-H2A.X and checkpoint kinase 1/2, respectively. Terminal deoxyribonucleotide-transferase-mediated dUTP nick-end labeling-positive cells were detected in renal tubules along with enhanced proapoptotic BAX/cleaved caspase-3 and reduced antiapoptotic BCL2. Scavenging ROS by cutaneous postexposure application of the antioxidant N-acetyl-l-cysteine reduced lewisite-induced autophagy and DNA damage. In summary, we provide evidence that topical exposure to lewisite causes AKI. The molecular mechanism underlying these changes involves ROS-dependent activation of autophagy and DDR pathway associated with the induction of apoptosis.

Molecular Mechanism Underlying Pathogenesis of Lewisite-Induced Cutaneous Blistering and Inflammation: Chemical Chaperones as Potential Novel Antidotes.

Lewisite is a potent arsenic-based chemical warfare agent known to induce painful cutaneous inflammation and blistering. Only a few modestly effective antidotes have so far been described in the literature. However, the discovery of effective antidotes for lewisite was hampered by the paucity of the exact molecular mechanism underlying its cutaneous pathogenesis. We investigated the molecular mechanism underlying lewisite-induced cutaneous blistering and inflammation and describe its novel antidotes. On the basis of our initial screening, we used a highly sensitive murine model that recapitulates the known human pathogenesis of arsenicals-induced cutaneous inflammation and blistering. Topically administered lewisite induced potent acute inflammation and microvesication in the skin of Ptch1(+/-)/SKH-1 mice. Even at a very low dose, lewisite up-regulates unfolded protein response signaling, inflammatory response, and apoptosis. These cutaneous lesions were associated with production of reactive oxygen species and extensive apoptosis of the epidermal keratinocytes. We confirmed that activation of reactive oxygen species-dependent unfolded protein response signaling is the underlying molecular mechanism of skin damage. Similar alterations were noticed in lewisite-treated cultured human skin keratinocytes. We discovered that chemical chaperone 4-phenyl butyric acid and antioxidant N-acetylcysteine, which significantly attenuate lewisite-mediated skin injury, can serve as potent antidotes. These data reveal a novel molecular mechanism underlying the cutaneous pathogenesis of lewisite-induced lesions. We also identified novel potential therapeutic targets for lewisite-mediated cutaneous injury.

Mustard gas exposure and mortality among retired workers at a poisonous gas factory in Japan: a 57-year follow-up cohort study.

OBJECTIVES: Mustard gas (MG) has been the most widely used chemical warfare agent in the past century. However, few but conflicting data exist on the effects of MG exposure on long-term mortality. We investigated MG-related mortality in retired workers at a poisonous gas factory. METHODS: We assessed mortality rates among 2392 male and 1226 female workers, whose vital status could be determined through 31 December 2009, at a poisonous gas factory operating from 1929 to 1945 in Okuno-jima, Japan. The analysis employed standardised mortality ratios (SMRs) calculated using national and prefectural references and a Cox proportional hazard regression model. Applying the Kaplan-Meier method, we compared cumulative death rates in the study cohort stratified by an 'Okuno-jima MG Index' which represented the product of HRs derived for job category and length of service. RESULTS: Among male workers, we found significant excesses in mortality from upper respiratory tract cancer (SMR 3.06), liver cancer (1.67), lung cancer (2.01) and chronic bronchitis/emphysema (4.84) compared with the national population, as well as stomach cancer (1.20) versus the Hiroshima Prefecture population. When stratified into 3 subgroups by the Okuno-jima MG Index, those with a higher Okuno-jima MG Index had significantly higher cumulative rates of death from respiratory cancer and chronic bronchitis/emphysema. CONCLUSIONS: MG exposure significantly increases the long-term risk of death from respiratory cancer and chronic bronchitis/emphysema. The Okuno-jima MG Index may be a useful indicator for estimating cumulative MG exposure.

Down-regulation of TGF-b1, TGF-b receptor 2, and TGF-b-associated microRNAs, miR-20a and miR-21, in skin lesions of sulfur mustard-exposed Iranian war veterans.

Sulfur mustard (SM) affects divergent cellular pathways including cell cycle, apoptosis, necrosis, and inflammatory responses. SM-induced lesions in skin include late-onset hyper-pigmentation, xerosis, and atrophy. It seems that TGF-b signaling pathway is a major player for SM pathogenesis. Here, we have employed a real-time polymerase chain reaction (PCR) approach to evaluate the expression alterations of all TGF-b variants and their receptors in skin biopsies obtained from 10 Iran-Iraq war veterans. Using specific LNA primers, the expression alteration of a TGF-bR2 regulator, miR-20a, and TGF-b downstream target, miR-21, was also assessed in the same samples Our real-time PCR data revealed a significant down-regulation of TGF-b1 and TGF-bR2, the major mediators of TGF-b signaling pathway, in skin biopsies of SM-exposed patients (p = 0.0015 and p = 0.0115, respectively). Down-regulation of TGF-b signaling pathway seems to contribute in severe inflammation observed in SM-exposed patients' tissues. MiR-20a and miR-21, as two important TGF-b associated microRNAs (miRNAs), were also down-regulated in SM-exposed skin lesions, compared to those of control group (p = 0.0003). Based on our findings, these miRNAs could be directly or indirectly involve in the pathogenesis of SM. Altogether, our data suggest the suitability of TGF-b1, TGF-bR2, as well as miR-20a and miR-21 as potential biomarkers for diagnosis and treatment of SM-exposed patients.

Biologists napping while work militarized.

As researchers discover more agents that alter mental states, the Chemical Weapons Convention needs modification to help ensure that the life sciences are not used for hostile purposes, says Malcolm Dando.

[On necessity to modify biochemical methods for detecting organophosphorus componds in chemical weapons extinction objects (review of literature)].

The article covers problems of biochemical methods assessing organophosphorus toxic compounds in objects of chemical weapons extinction. The authors present results of works developing new, more specific and selective biochemical methods.

[On new screening biomarker to evaluate health state in personnel engaged into chemical weapons extinction].

The work was aimed to find new screeding parameters (biomarkers) for evaluation of health state of workers engaged into enterprises with hazardous work conditions, as exemplified by "Maradykovskyi" object of chemical weapons extinction. Analysis of 27 serum cytokines was conducted in donors and the object personnel with various work conditions. Findings are statistically significant increase of serum eotaxin in the personnel of "dirty" zone, who are regularly exposed to toxic agents in individual filter protective means over the working day. For screening detection of health disorders in the object personnel, the authors suggested new complex biomarker--ratio Eotaxin* IFNγ/TNFα that demonstrates 67.9% sensitivity and 87.5% specificity in differentiating the "dirty" zone personnel and other staffers.

Expression of glutathione S-transferase variants in human airway wall after long-term response to sulfur mustard.

CONTEXT: Sulfur mustard (SM) is an alkylating agent identified as a potent chemical warfare agent. More recently, SM was used in the Iraq conflict against Iranian troops and civilians. At present, there are many people suffering from chronic obstructive pulmonary disease (COPD) due to mustard gas in Iran. SM increases the endogenous production of reactive oxygen species (ROS). The oxidant/antioxidant imbalance present in the lungs of these patients also results from the impaired capacity of the antioxidant/detoxification enzymes to detoxify the harmful reactive oxygen metabolites. OBJECTIVE: One of the major antioxidants in human airways is glutathione S-transferase. They facilitate the detoxification of various environmental of oxidative stress. In this study, we attempted to understand the significance different in expression of GSTs in airway wall of chemical patients and control. MATERIALS AND METHODS: Seven normal and 20 SM induced COPD individuals were studied. Bronchoscopy was performed in all subjects and two specimens were taken from the main bronchus for mRNA extraction, PCR analysis and immunohistochemistry. RESULTS: SM-induced COPD individuals showed expression of GSTA1 2.51 ± 0.83-, GSTM1 2.84 ± 1.71- and GSTP1 5.61 ± 2.59-folds higher than those of controls that revealed. GSTP1-immunoreactivity was strongly expressed in luminal border of normal samples. SM patient samples immunoreactivity for GSTP1 in the same area were negative. DISCUSSION AND CONCLUSION: According to these findings, we speculated that overexpression of GSTs mRNA in patients revealed that GSTs plays an important role in cellular protection against oxidative stress of MS in airway wall of patients.

Project update: evaluating the community health legacy of WWI chemical weapons testing.

The Spring Valley community of Washington, District of Columbia, was built on the site of a World War I chemical weapons lab where testing activities had distributed arsenic to surface soil and waste disposal had resulted in localized subsurface contamination. In previous work, findings were suggestive of potential site-related health issues, although no evidence of cancer clustering was found. In follow-up, we updated the community health assessment and explored time trends for several arsenic-related cancers. Health indicators continue to be very good in Spring Valley. For all major causes of mortality, Spring Valley rates were lower than United States (US) rates with most substantially lower (20-80 %); rates for heart diseases, Alzheimer's, and essential hypertension and related kidney disease were only slightly lower than US rates (3-8 %). Incidence and mortality rates for the selected cancers in the Spring Valley area were lower than US rates. Small non-statistically significant increasing time trends were observed in Spring Valley for incidence of two arsenic-related cancers: bladder and lung and bronchus. A moderate statistically significant increasing rate trend was observed for lung and bronchus cancer mortality in Spring Valley (p < 0.01). Lung and bronchus cancer mortality rates were also increasing in the Chevy Chase community, the local comparison area closely matched to Spring Valley on important demographic variables, suggesting that the observed increases may not be site-related. A full profile of common cancer site rates and trends for both study areas was suggested to better understand the rate trend findings but no epidemiological study was recommended.

[Medical aspects of common non-lethal weapons]. / Medizinische Aspekte gängiger nicht-letaler Wirkmittel.

The development and provision of non-lethal weapons (NLW) allow military and law enforcement personnel to exploit gradual engagement in countering potentially hazardous threats. Chemical, kinetic and electrical weapons systems are used to curb violence in civilian crowds. With inappropriate usage, these technologies can cause potentially fatal injuries that are not only of clinical, but also of legal relevance. In this context, the practicing physician is faced with treatment as well as assessment issues of new forms of injuries. In order to assure medical care and to be able to draw competent expert's conclusions, a detailed knowledge of the medical effects of these NLW is necessary. The review at hand presents today's most popular NLW and gives an overview of their possible injury potential and required treatments.

[Life quality parameters in prenosologic evaluation of health state in residents of protective measures area near objects of storage and destruction of chemical weapons].

The article presents results of life quality assessment and subjective evaluation data on health state, used for prenosologic evaluation of health state in residents of protective measures area near objects of storage and destruction of chemical weapons. Considering specific features of residence near potentially dangerous objects, the authors conducted qualitative evaluation of satisfaction with various life facets, with taking into account the objects specificity, established correlation between life quality and self-evaluation of health with factors influencing public health state.

Tissue plasminogen activator prevents mortality from sulfur mustard analog-induced airway obstruction.

Sulfur mustard (SM) inhalation causes the rare but life-threatening disorder of plastic bronchitis, characterized by bronchial cast formation, resulting in severe airway obstruction that can lead to respiratory failure and death. Mortality in those requiring intubation is greater than 80%. To date, no antidote exists for SM toxicity. In addition, therapies for plastic bronchitis are solely anecdotal, due to lack of systematic research available to assess drug efficacy in improving mortality and/or morbidity. Adult rats exposed to SM analog were treated with intratracheal tissue plasminogen activator (tPA) (0.15-0.7 mg/kg, 5.5 and 6.5 h), compared with controls (no treatment, isoflurane, and placebo). Respiratory distress and pulse oximetry were assessed (for 12 or 48 h), and arterial blood gases were obtained at study termination (12 h). Microdissection of fixed lungs was done to assess airway obstruction by casts. Optimal intratracheal tPA treatment (0.7 mg/kg) completely eliminated mortality (0% at 48 h), and greatly improved morbidity in this nearly uniformly fatal disease model (90-100% mortality at 48 h). tPA normalized plastic bronchitis-associated hypoxemia, hypercarbia, and lactic acidosis, and improved respiratory distress (i.e., clinical scores) while decreasing airway fibrin casts. Intratracheal tPA diminished airway-obstructive fibrin-containing casts while improving clinical respiratory distress, pulmonary gas exchange, tissue oxygenation, and oxygen utilization in our model of severe chemically induced plastic bronchitis. Most importantly, mortality, which was associated with hypoxemia and clinical respiratory distress, was eliminated.