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Introduction Hypertension is associated with adverse cardiovascular outcomes and is geographically concentrated in urban underserved neighborhoods. This study examines the temporal–spatial association between individual exposure to violent crime and blood pressure. Methods A retrospective observational cohort study analyzed 39,211 patients with 227,595 blood pressure measurements from 2014 to 2016 at 3 outpatient clinics at an academic medical center in Chicago. Patients were included in the study if they had documentation of blood pressure in the medical record and resided in census tracts with >1,000 observations. Geocoded violent crime events were obtained from the Chicago Police Department. Individual-level exposure was defined on the basis of spatial and temporal buffers around each patient's home. Spatial buffers included 100-, 250-, 500-, and 1,000-meter disc radii, and temporal buffers included 7, 30, and 60 days preceding each outpatient appointment. Systolic blood pressure measurements (mmHg) were abstracted from the electronic health record. Analysis was performed in 2019–2020. Results For each violent crime event within 100 meters from home, systolic blood pressure increased by 0.14 mmHg within 7 days of exposure compared with 0.08 mmHg at 30 days of exposure. In analyses stratified by neighborhood cluster, systolic blood pressure increased by 0.37 mmHg among patients in the suburban affluent cluster relative to that among those in an extreme poverty cluster for the same spatial and temporal buffer. Conclusions Exposure to a violent crime event was associated with increased blood pressure, with gradient effects by both distance and time from exposure.

Discovered in 1829, thorium, CASRN 7440-29-1, is a naturally occurring radioactive metal with no stable isotopes. It is about as abundant as lead. Soil commonly contains an average of about six parts of thorium per million parts of soil. Ingestion of liquid, inhalation of dust or gas, and percutaneous absorption are the routes of exposure. Acute exposure results in dermatitis. Thorium is a carcinogen and developmental toxin. The removal of thorium from the body has been achieved by the use of chelating agents. Studies of thorium workers have shown that breathing thorium dust may cause an increased chance of developing lung disease and cancer of the lung or pancreas many years after being exposed.

Researchers have theorized that exposure to racial discrimination may impair executive functioning. The limited existing data broadly support this notion and suggest that discrimination may exert acute and persistent effects on executive functioning, potentially because of the cognitive demands associated with responding to discrimination. However, it is unclear if discrimination is differentially associated with different core executive functions. Further, the effects may vary depending on the timing of exposure, as recent or acute exposure to discrimination may operate on executive functioning through different mechanisms than exposure across the lifetime. The current study evaluates the relations of both recent and lifetime exposure to racial discrimination to three core executive functions (i.e., cognitive flexibility, inhibitory control and working memory) using a racially and ethnically diverse sample (n = 319). In fully adjusted models, recent discrimination was negatively associated with cognitive flexibility and working memory but not with inhibitory control. These data are consistent with the broader literature on acute stress effects on core executive functions and may have implications for understanding the effects of discrimination on health. Further research is warranted to understand the course and mechanisms of effects of lifetime and recent discrimination on core executive functions.

PURPOSE: The potential for malicious use of radiation, or radiation accidents could potentially lead to acute, high radiation doses to the public. Following acute accidental exposure to high doses of radiation, medical intervention is pivotal to the survivability of the patient, and the sooner the appropriate measures are taken the better the odds for survival. Early estimates of acute accidental radiation doses can be determined via biomarkers such as dicentric chromosome analysis or scenario reconstruction using computer software. However, both take valuable time and can be expensive. Increased frequencies of abnormal neutrophils in peripheral blood, referred to as pseudo Pelger-Huët anomalies (PPHAs), have been shown to be potential biomarkers of radiation exposure in several scenarios, including the 1958 Y-12 criticality accident and the radium dial painters. PPHAs are potentially a faster and cheaper quantitative biomarker for radiation exposure, and here they were evaluated in acutely exposed rhesus macaques. METHODS AND MATERIALS: Peripheral blood smears from acutely exposed rhesus macaques were evaluated for the percentage of neutrophils that displayed the PPHA morphology using light microscopy. Irradiated animals received 0 to 8.5 Gy total body radiation using one of two strategies: (1) linear accelerator-produced 6 MV photons delivered at 80 cGy/minute; or (2) Cobalt 60-produced gamma irradiation delivered at 60 cGy/min. Zero dose animals were used to determine a baseline percentage of PPHAs, and blood smears taken periodically throughout the lifetime of exposed animals post-irradiation were used to determine the persistence and biokinetics of PPHAs. RESULTS: The baseline prevalence of the PPHA in rhesus macaques was determined to be 0.58 ± 0.46%. The dose-response curve with doses ranging from 0 Gy to 8.5 Gy (LD90/30) displayed a strong positive correlation between PPHA percentage and acute radiation dose (R(2) of 0.88 p = 3.62 × 10(−22)). Statistically significant differences were found when animals were separated into dose cohorts of 0, 4, 6.4–6.5, and 8–8.5 Gy. The biokinetics model utilized only 4 Gy exposures and blood smears taken periodically over 3.1 years post-irradiation. PPHA morphology increases quickly following irradiation and appears stable over 3.1 years post-irradiation. CONCLUSION: PPHA morphology was confirmed to be present in rhesus macaques, a dose-response relationship was constructed, and it is stable over 3 years post-irradiation. This study demonstrates that PPHA analysis can be a fast and cheap method of biodosimetry. Future studies will work to determine the accuracy of dose determination and lower limits of detection.

Introduction: Hypoxia, often referred to as “silent killer,” a common aeromedical stressor in aviation, may have catastrophic events in-flight unless recognized well in time. On exposure to hypoxia, an individual manifests a specific spectrum of symptoms referred to as “hypoxia signature.” The present study was conducted to assess the manifestation of “hypoxia signature” on repeated exposure to simulated hypobaric hypoxia for its potential usage as a tool for hypoxia recognition. Material and Methods: Twenty-two healthy adult volunteers were subjected to a simulated altitude of 22,000 feet for a duration of 5 min in the hypobaric altitude chamber. The symptoms experienced by the participants at the said altitude were recorded using a questionnaire. The heart rate (HR) and oxygen saturation (SpO2) were recorded during the exposure. The hypoxia exposure was repeated two more times with a minimum interval of 3 weeks between each. Paired t-test was used to compare the mean values of physiological parameters (HR and SpO2) between ground level and 22000 feet recorded in all the three exposures. The hypoxia symptoms and their severity reported during the exposures were compared with those of recalled symptoms (reported after 3 weeks of exposure) using McNemar test and Wilcoxon Signed Rank test, respectively. Results: Paired t-test revealed a statistically significant increase in HR and fall in SpO2 with rise in altitude from ground level to 22000 feet. The three most common symptoms consistently observed were lightheadedness, thinking slow, and warm feeling. The common hypoxic symptoms and their severity scores reported at 22,000 feet compared with recalled counterpart during subsequent exposures did not reveal any significant differences (P > 0.05). Conclusion: There was a high degree of similarity in the frequency and severity score of symptoms between acute exposure to hypobaric hypoxia and recall indicating evidence of repeatability of symptoms across the three sessions of hypoxia exposure within the individuals. This brings out the usefulness of “hypoxia signature” as a tool for hypoxia recognition and its application in hypoxia indoctrination and training for aircrew.

Background Epidemiologic studies of radiation-exposed populations form the basis for human safety standards. They also help shape public health policy and evidence-based health practices by identifying and quantifying health risks of exposure in defined populations. For more than a century, epidemiologists have studied the consequences of radiation exposures, yet the health effects of low levels delivered at a low-dose rate remain equivocal. Materials and methods The Million Person Study (MPS) of U.S. Radiation Workers and Veterans was designed to examine health effects following chronic exposures in contrast with brief exposures as experienced by the Japanese atomic bomb survivors. Radiation associations for rare cancers, intakes of radionuclides, and differences between men and women are being evaluated, as well as noncancers such as cardiovascular disease and conditions such as dementia and cognitive function. The first international symposium, held November 6, 2020, provided a broad overview of the MPS. Representatives from four U.S. government agencies addressed the importance of this research for their respective missions: U.S. Department of Energy (DOE), the Centers for Disease Control and Prevention (CDC), the U.S. Department of Defense (DOD), and the National Aeronautical Space Agency (NASA). The major components of the MPS were discussed and recent findings summarized. The importance of radiation dosimetry, an essential feature of each MPS investigation, was emphasized. Results The seven components of the MPS are DOE workers, nuclear weapons test participants, nuclear power plant workers, industrial radiographers, medical radiation workers, nuclear submariners, other U.S. Navy personnel, and radium dial painters. The MPS cohorts include tens of thousands of workers with elevated intakes of alpha particle emitters for which organ-specific doses are determined. Findings to date for chronic radiation exposure suggest that leukemia risk is lower than after acute exposure; lung cancer risk is much lower and there is little difference in risks between men and women; an increase in ischemic heart disease is yet to be seen; esophageal cancer is frequently elevated but not myelodysplastic syndrome; and Parkinson's disease may be associated with radiation exposure. Conclusions The MPS has provided provocative insights into the possible range of health effects following low-level chronic radiation exposure. When the 34 MPS cohorts are completed and combined, a powerful evaluation of radiation-effects will be possible. This final article in the MPS special issue summarizes the findings to date and the possibilities for the future. A National Center for Radiation Epidemiology and Biology is envisioned.

We investigated whether individual rainbow trout (Oncorhynchus mykiss; 9–53 g) avoid a potentially lethal level of total dissolved gas (TDG) supersaturation using lateral movements during an acute exposure. As there is no mechanism by which fish can detect and avoid TDG supersaturation in shallow water, we hypothesize that rainbow trout do not directly detect TDG supersaturation. Most previous studies have tested TDG avoidance in groups of fish, which may confound responses because many fishes, such as juvenile rainbow trout, display territorial behavior. We placed rainbow trout individually into a flume and allowed them to swim freely between two channels for 6 min: one channel contained water at 145% TDG and the other contained air-equilibrated water. We then switched treatments between channels and tested fish in the same way for an additional 6 min. We quantified the duration spent by fish in each channel during the last 2 min of each 6 min exposure. Fish spent a mean duration of 11s longer in 145% TDG water compared to air-equilibrated water, and the inclusion of TDG treatment as a factor improved the model of the duration spent by fish in a channel. These results indicate that fish did not avoid a potentially lethal level of TDG. This suggests that some fishes in shallow water may be unable to avoid harmful TGD supersaturation generated by events such as spilling from hydroelectric dams.

The case definition of inhalational constrictive bronchiolitis (CB) has changed over the generations. We identify changes in the description of this illness over time associated with different exposures and present the natural history of CB in a case attributed to military burn pit exposure. The initial descriptions of this disease began with nitric acid spills and silage exposures. In these events, there was an acute exposure, typically a short-term resolution of the adverse respiratory events, and then a progression, leading to disability or a respiratory death. The life-saving role of corticosteroid therapy in this situation was recognized. War gas exposures of World War I and then Saddam Hussein's use of sulfur mustard gas in the Iran-Iraq War followed. More recently the findings associated with diacetyl exposure in commercial popcorn workers remained consistent with previously described presentations, but then the clinical presentation in troops returning from deployment to Southwest Asia was very different, yet with the same histologic findings. We recognize unreconciled disparities in the clinical, physiologic, and imaging presentation in those with inhalational bronchiolitis and acknowledge this as perhaps one of the difficult diagnoses in respiratory medicine.

The development of whole-body inhalational chambers for acute toxicity risk assessment of aerosols in rodents is of key importance in clinical and occupational hazard evaluations. The key aim of study is the design, development, optimization, and validation of an inhalational chamber using water aerosol, vehicle, and Aroclor 1232. The second goal has been to apply this chamber in the risk assessment of Aroclor 1232. Broncho-alveolar Lavage fluid cytology and chromatography, and lung histopathology were used to supplement the validation process. PCB concentrations were uniformly distributed across different places inside the chamber and a MMAD generation of 4.3 µm ± 1.7 µm GSD was suggestive of lower airway atomization of PCB particles. The chamber environmental parameters were within acceptable limits for rodents during the experimental procedures. Mouse behavioral alterations were minimal during water aerosolization. Acute exposure to Aroclor 1232 showed reproducibility of behavioral scores. Benchmark dose for further studies using Aroclor 1232 was derived at 4 mg/cu.m. Its toxicities could be verified by correlating the behavioral scores, neurobehavioral functions with concentrations in plasma and BAL fluid samples from Swiss albino mice. The rodent chamber can be utilized for risk assessment of occupational hazards such as complex pollutant mixtures and particulate matter aerosols. The inhalational chamber possesses the versatility to enable assessment of toxicological mixtures across sub-acute toxicity timelines.

Cadmium (Cd) exposure can impair the traits of aquatic animals associated with reproduction. In natural lakes Cd is typically detected at concentrations below 0.001 mg l-1 . The authors investigated the impact of ultra-acute Cd exposure on sperm motility in European whitefish (Coregonus lavaretus). They activated sperm with water containing various nominal concentrations of Cd and recorded sperm motility parameters. Only the highest Cd concentration (500 mg l-1 ) was associated with decreased sperm swimming velocity and increases in both the percentage of static cells and curvature of the sperm swimming trajectory. The results indicate that environmentally realistic concentrations of Cd during the sperm motility activation are not critically harmful to male C. lavaretus fertilization potential.

Almost half of the world’s population still practice biomass fuel burning for various domestic purposes. About 1.6 million deaths are attributed to acute exposure to indoor air pollutants in India. A very few attempts have been made in the eastern part of India for remediation from household air pollution through the intervention of improved cookstoves. In this study, an attempt has been made to curb the pollution level by substituting traditional biomass cookstoves with an improved cookstove. The concentrations of pollutants (CO, CO2, O3, NO2, SO2, PM2.5, PM10 and TSPM) were measured, and health parameters were assessed before and after installation of the improved cookstove. Results revealed that the pollution was reduced and health parameters were improved significantly (p

Extremely low-frequency electromagnetic fields (ELF EMFs) have been shown to impact the behavior and physiology of insects. Recent studies have highlighted the need for more research to determine more specifically how they affect flying insects. Here, we ask how locust flight is affected by acute exposure to 50 Hz EMFs. We analyzed the flights of individual locusts tethered between a pair of copper wire coils generating EMFs of various frequency using high-speed video recording. The mean wingbeat frequency of tethered locusts was 18.92 ± 0.27 Hz. We found that acute exposure to 50 Hz EMFs significantly increased absolute change in wingbeat frequency in a field strength-dependent manner, with greater field strengths causing greater changes in wingbeat frequency. The effect of EMFs on wingbeat frequency depended on the initial wingbeat frequency of a locust, with locusts flying at a frequency lower than 20 Hz increasing their wingbeat frequency, while locusts flying with a wingbeat frequency higher than 20 Hz decreasing their wingbeat frequency. During the application of 50 Hz EMF, the wingbeat frequency was entrained to a 2:5 ratio (two wingbeat cycles to five EMF cycles) of the applied EMF. We then applied a range of ELF EMFs that were close to normal wingbeat frequency and found that locusts entrained to the exact frequency of the applied EMF. These results show that exposure to ELF EMFs lead to small but significant changes in wingbeat frequency in locusts. We discuss the biological implications of the coordination of insect flight in response to electromagnetic stimuli. © 2021 Bioelectromagnetics Society.

Introduction. Shellfish poisoning could be caused by ingestion of shellfish contaminated by bacteria, viruses, heavy metals, pesticides, marine biotoxins etc. The objective of the study was to determine the theoretical human exposure to shellfish toxins of Bulgarian consumers. The incidence of registered cases of intoxications due to marine biotoxins ingestion – “Toxic effect: Other fish and shellfish poisoning (T61.2)” in regional hospitals was investigated. Materials and methods. Acute exposure (AE), chronic exposure (CE) and hazard quotient (HQ) are calculated based on experimentally-determined levels of shellfish toxins in mussels harvested from North Bulgarian coast in the period 2012 – 2018. We performed a retrospective analysis of the frequency of the diagnosis T61.2, based on medical documentation for the period 1.05.2012 – 7.12.2018 in hospitals in Varna and Dobrich, Bulgaria. Results. Shellfish toxins that most often occur in mussels are domoic acid (DA), yessotoxin (YTX) and pectenotoxin-2 (PTX2). The calculated maximum AE was 1.00 mg/kg bw for DA, 0.02 mg/kg bw for YTX and 0.0045 mg/kg bw for PTX2, respectively. Maximum CE for DA was 0.01 mg/kg bw/day. All estimated values were much lower than those legislated by European Food Safety Authority thresholds. The exposure to marine biotoxins was estimated based on contamination data of mussels harvested from the same region. The analysis for the whole period showed that its frequency is lower than 1%. Clinicians report that this diagnosis is presumptive, based on recent ingestion of shellfish and presence of symptoms consistent with shellfish poisoning. Conclusions. Estimated theoretical acute and chronic exposures agree upon the incidence of clinical cases with the studied diagnosis. A parallel investigation on a prolonged period is required, to increase the accuracy of these results.

Acute exposure to hydrogen sulfide initiates a series of hallmark biological effects that occur progressively at increasing exposure levels: odor perception, conjunctivitis, olfactory paralysis, "knockdown," pulmonary edema, and apnea. Although effects of exposure to high concentrations of hydrogen sulfide are clear, effects associated with chronic, low-level exposure in humans is under debate, leading to uncertainty in the critical effect used in regulatory risk assessments addressing low dose exposures. This study integrates experimental animal, observational epidemiology, and occupational exposure evidence by applying a pathway-based approach. A hypothesized adverse outcome pathway (AOP) network was developed from 34 studies, composed of 4 AOPs sharing 1 molecular initiating events (MIE) and culminating in 4 adverse outcomes. A comparative assessment of effect levels and weight of evidence identified an AOP leading to a biologically-plausible, low-dose outcome relative to the other outcomes (nasal lesions, 30 ppm versus olfactory paralysis,100 ppm; neurological effects,80 ppm; pulmonary edema,80 ppm). This AOP (i.e. AOP1) consists of the following key events: cytochrome oxidase inhibition (10 ppm), neuronal cell loss (30 ppm), and olfactory nasal lesions (defined as both neuronal cell loss and basal cell hyperplasia;30 ppm) in rodents. The key event relationships in this pathway were supported by moderate empirical evidence and have high biological plausibility due to known mechanistic understanding and consistency in observations for diverse chemicals.

Thiamethoxam is a neurotoxic systemic insecticide belonging to the neonicotinoid family. Approved under the trade Algeria Actara WG 25%, the plant protection product is recognized as toxic to the bees after acute exposure. However, this product is persistent, has a significant residual activity and accumulates in plants. It is therefore necessary to completely reassess its toxicity. To do this, we determined the sensitivity of the Saharan and Tellian honeybee, Apis mellifera sahariensis and Apis mellifera intermissa, to thiamethoxam by testing the acute oral toxicity on worker bees in the laboratory. The study is based on determining the LD50 according to the volume administrated. Each batch of bees was fed 100, 200, 500 and 1000μl (5, 10, 25 and 50μl per bee) 55,5% (w/v) sucrose solution with increasing doses (1, 10, 20, 50, 70 and 90 ng per bee) of thiamethoxam dissolved in acetone, for trial treatments, and 55,5% (w/v) sucrose solution supplemented with acetone, control treatments. The results showed that the toxicity is manifested by acute symptoms of early neurotoxicity and cumulative mortalities that occur 24 hours after treatment. The LD50 varies with the volume administered. Indeed, the LD50 values decrease with increasing volume, and there is an inverse relationship between the LD50 obtained and administered volumes.

In this study, the acute impacts of aqueous methoxychlor exposure on the viability, locomotive behavior, and heartrate of Daphnia magna was assessed. Adults were exposed to 0 (ethanol control), 1, ...

PURPOSE: The long-term effect of low and moderate doses of ionizing radiation on the lens is still a matter of debate and needs to be evaluated in more detail. MATERIAL AND METHODS: We conducted a detailed histological analysis of eyes from B6C3F1 mice cohorts after acute gamma irradiation (60Co source; 0.063 Gy/min) at young adult age of 10 weeks with doses of 0.063, 0.125 and 0.5 Gy. Sham irradiated (0 Gy) mice were used as controls. To test for genetic susceptibility heterozygous Ercc2 mutant mice were used and compared to wild type mice of the same strain background. Mice of both sexes were included in all cohorts. Eyes were collected 4 hours, 12, 18 and 24 months after irradiation. For a better understanding of the underlying mechanisms, metabolomics analyses were performed in lenses and plasma samples of the same mouse cohorts at 4 and 12 hours as well as 12, 18 and 24 months after irradiation. For this purpose, a targeted analysis was chosen. RESULTS: This analysis revealed histological changes particularly in the posterior part of the lens that rarely can be observed by using Scheimpflug imaging, as we reported previously. We detected a significant increase of posterior subcapsular cataracts 18 and 24 months after irradiation with 0.5 Gy (odds ratio 9.3; 95%-confidence interval 2.1 - 41.3) independent of sex and genotype. Doses below 0.5 Gy (i.e. 0.063 and 0.125 Gy) did not significantly increase the frequency of posterior subcapsular cataracts at any time point. In lenses, we observed a clear effect of sex and aging but not of irradiation or genotype. While metabolomics analyses of plasma from the same mice showed only a sex effect. CONCLUSIONS: This paper demonstrates a significant radiation-induced increase in the incidence of posterior subcapsular cataracts, which could not be identified using Scheimpflug imaging as the only diagnostic tool.

Tambaqui (Colossoma macropomum) are a model species for tropical fish physiology, but details are lacking about their ionoregulatory response to acid waters. To provide specifics, we measured unidirectional Na+ fluxes in low pH waters. Sodium influx ( $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ ) was uninhibited during acute exposure to pH 4.5 and 3.5, and Na efflux ( $$J_{{{\text{out}}}}^{{{\text{Na}}}}$$ ) rose only slightly at pH 3.5; net Na+ flux ( $$J_{{{\text{net}}}}^{{{\text{Na}}}}$$ ) remained positive at all pH. Similarly, during 24 h transfer to pH 3.5 $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ , $$J_{{{\text{out}}}}^{{{\text{Na}}}}$$ , and $$J_{{{\text{net}}}}^{{{\text{Na}}}}$$ were unchanged at all times. Taking a closer look at the mechanism of Na+ transport in the gills of tambaqui we found that $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ was uninhibited by HMA, a Na+/H+-exchanger blocker, and Benzamil, a Na+-channel inhibitor, casting doubt on their role in Na+ uptake in this fish. Measurement of Na+/K+-ATPase (NKA) and H+-ATPase (VHA) activity showed that neither changed at low pH compared to measurements at pH 6.5. Western blot analysis of ATPase expression saw no changes in amount of NKA and VHA at low pH, and immunohistochemistry showed expression of both NKA and VHA on lamellae and interlamellar region of tambaqui gills and that both proteins co-localized to the same gill cells. Location of expression also did not change in low pH water. Amazingly, tambaqui seem unaffected by pH 3.5 water, making them one of the most acid-tolerant fish species examined so far. In addition, they appear to share key ionoregulatory traits with other fish of the order Characiformes, which suggest a common origin for the ionoregulatory attributes.

Background Von Willebrand factor (VWF) contains a number of free thiols, the majority of which are located in its C-domains, and these have been shown to alter VWF function, However, the impact of free thiols on function following acute exposure of VWF to collagen under high and pathological shear stress has not been determined. Methods VWF free thiols were blocked with N-ethylmaleimide and flow assays performed under high and pathological shear rates to determine the impact on platelet capture and collagen binding function. Atomic force microscopy (AFM) was used to probe the interaction of VWF with collagen and molecular simulations conducted to determine the effect of free thiols on the flexibility of the VWF-C4 domain. Results Blockade of VWF free thiols reduced VWF-mediated platelet capture to collagen in a shear-dependent manner, with platelet capture virtually abolished above 5000 s-1 and in regions of stenosis in microfluidic channels. Direct visualization of VWF fibers formed under extreme pathological shear rates and analysis of collagen-bound VWF attributed the effect to altered binding of VWF to collagen. AFM measurements showed that thiol-blockade reduced the lifetime and strength of the VWF-collagen bond. Pulling simulations of the VWF-C4 domain demonstrated that with one or two reduced disulphide bonds the C4 domain has increased flexibility and the propensity to undergo free-thiol exchange. Conclusions We conclude that free thiols in the C-domains of VWF enhance the flexibility of the molecule and enable it to withstand high shear forces following collagen binding, demonstrating a previously unrecognized role for VWF free thiols.

Asian swamp eel, Monopterus albus/javanensis [Zuiew, 1973/Lacepede 1800], has been established in the southeastern USA since at least 1994, yet little is known about its ability to survive low winter temperatures. We use standard thermal methodologies to quantify low temperature responses and provide a detailed description of swamp eel reactions to cold temperatures. When exposed to chronic temperature decreases of 1.0 °C day-1, swamp eel ceased foraging at 15.0 °C, markedly diminished movements below 11.0 °C, and became incapacitated near 9.6 °C. During critical thermal minima trials, swamp eel exposed to acute temperature drops (0.25 °C min-1) tolerated temperatures as low as 6.2 °C. Swamp eel exhibited a moderate cold acclimation response, gaining 0.23 °C in cold tolerance for every 1 °C drop in acclimation temperature. Progressive time-series critical thermal minimum temperatures (CTmin) estimates for eel acclimated to 20.5 °C followed by an acute temperature decrease to 16.0 °C, revealed that cold acclimation may occur in only 8 days. Fringe populations of swamp eel in their native range periodically experience colder winter temperatures, which may explain the ability of introduced populations to survive winter cold fronts in Florida. Understanding Asian swamp eel acute and chronic thermal limits may be useful in assessing dispersal risk and range expansion in the southeastern USA.

INTRODUCTION: Hypergolic propellants can be released in large amounts during space launch contingencies. Whether propellant-contaminated suit fabric poses a significant risk to rescue crews, due to off-gassing, has not been explored in detail. In this study, we addressed this issue experimentally, exposing space suit fabric to propellants (dinitrogen tetroxide [N2O4] and monomethyl hydrazine [MMH]).METHODS: The NASA Space Shuttle Program Advanced Crew Escape System II (ACES II) is similar to the NASA Orion Crew Survival System (OCSS) and was utilized here. Suit fabric was placed and sealed into permeation cells. Fabric exterior surface was exposed to constant concentrated hypergolics, simulating permeation and leakage. Fabric was rinsed, and permeation and off-gassing kinetics were measured. Experimental parameters were selected, simulating suited flight crewmembers during an evacuation transport without cabin air flow.RESULTS: The fabric allows for immediate permeation of liquid or vaporized MMH and N2O4. NO2 off-gassing never exceeded the AEGL-1 8-h level (acute exposure guideline level). In contrast, MMH off-gassing levels culminated in peak levels, approaching AEGL-2 10-min levels, paralleling the drying process of the fabric layers. DISCUSSION: Our findings demonstrate that MMH off-gassing is promoted by the drying of suit material in a delayed fashion, resulting in MMH concentrations having the potential for adverse health effects for flight and rescue crews. This indicates that shorter decontamination times could be implemented, provided that suit material is either kept moist to prevent off-gassing or removed prior to medical evacuation. Additional studies using OCSS or commercial crew suits might be needed in the future.Schwertz H, Roth LA, Woodard D. Propellant off-gassing and implications for triage and rescue. Aerosp Med Hum Perform. 2020; 91(12):956961.

The article substantiates the mechanisms and significance of the increased contents of blood plasma cholesterol and high density lipoproteins (HDLP) under acute exposure to stress factors leading to activation of metabolism. To a great extent, these changes reflect the adaptation rearrangements in cell membranes that are predominantly haracterized by a decreased content of free cholesterol in their composition due to its efflux to HDLP particles . The changes in HDLP fatty acid composition also contribute to this process resulting in a reduction of membrane microviscosity so that to intensify the intracellular metabolism and to enhance cellular functional activity.

Introduction In modern conditions, caused by the pandemic of a new type of viral infection Covid 19, the use of paracetamol, which has hepatotoxic properties in overdose, has increased It seems relevant to study metabolic disorders in the liver in acute paracetamol intoxication and evaluate the effectiveness of the timely use of hepatoprotective drugs The purpose of this study is an experimental assessment of metabolic changes at the early stages of paracetamol exposure and pharmacological correction of toxic liver lesions with oxymethyluracil in comparison with known hepatoprotectors - ademetionine and Mexidol Material and methods Acute intragastric administration of paracetamol to laboratory animals was performed, and the corrective effect of the drug oxymethyluracil was studied in comparison with “Heptor” and “Mexidol” Biochemical studies of biomaterial of laboratory animals were conducted Results The analysis found the use of known hepatoprotectors and oxymethyluracil after exposure to paracetamol to normalize the biochemical parameters that characterize the functional state of the liver in laboratory animals Conclusion Oxymethyluracil, along with known hepatoprotectors, has a protective effect on the liver of laboratory animals under acute exposure to paracetamol comparable to, and in some cases exceeding, the corrective action of “Heptor” and “Mexidol” Введение В современных условиях, вызванных пандемией нового вида вирусной инфекции COVID-19, возросло применение парацетамола, обладающего гепатотоксическими свойствами при передозировке Представляется актуальным изучение метаболических нарушений в печени при острой интоксикации парацетамолом и оценка эффективности своевременного применения гепатопротективных препаратов Цель настоящего исследования - экспериментальная оценка метаболических изменений на ранних сроках воздействия парацетамола и фармакологическая коррекция токсических поражений печени оксиметилурацилом в сравнении с известными гепатопротекторами - «Гептором» и «Мексидолом» Материал и методы Проведено острое внутрижелудочное введение парацетамола лабораторным животным, изучено корректирующее действие препарата оксиметилурацила в сравнении с «Гептором» и «Мексидолом» Проведены биохимические исследования биоматериала лабораторных животных Результаты По результатам анализа установлено, что при применении известных гепатопротекторов и оксиметилурацила после воздействия парацетамолом происходит нормализация биохимических показателей, характеризующих функциональное состояние печени у лабораторных животных Заключение Оксиметилурацил наряду с известными гепатопротекторами оказывает защитное действие на печень лабораторных животных при остром воздействии парацетамолом, сопоставимое, а в некоторых случаях и превышающее корректирующее действие препаратов «Гептор» и «Мексидол»

Introduction. Among noninfectious diseases, one of the leading places belongs to pathologies caused by the action of industrial toxicants. In this regard, the search for drugs for the prevention and treatment of various intoxications is one of the priority tasks of public health. Treatment of intoxication with drugs with antioxidant and antihypoxic activity is more effective. The aim of this study was to investigate morphological changes in parenchymal organs (liver, kidneys, and pancreas) under acute exposure to high doses of carbon tetrachloride and to evaluate the effectiveness of their correction with a new composition of oxymethyluracil with ascorbic acid. Material and methods. The composition of 5-hydroxy-6-methyluracil with ascorbic acid was first synthesized at the Ufa Institute of Chemistry, Ufa Federal Research Center, RAS. The preventive effect of the new drug was studied in comparison with “Heptor” on the carbon tetrachloride-induced liver injury model. Morphological studies of the liver, pancreas, and kidneys of laboratory animals were carried out. Results. Studies have shown the prophylactic administration of new composition of 5-hydroxy-6-methyluracil with ascorbic acid to have a protective effect on the structure of parenchymal organs in acute carbon tetrachloride intoxication, comparable to the drug “Heptor” (possibly superior). However, reparative properties were observed only in the drug “Heptor”. Conclusion. Comparative estimation of morphological changes in parenchymal organs under acute exposure to high doses of carbon tetrachloride indicates the protective effect of prophylactic administration of the composition of 5-hydroxy-6-methyluracil with ascorbic acid, comparable to the drug “Heptor” (possibly superior).

By definition, low doses are minimum doses of a damaging agent, in particular radiation, causing a recorded biological effect. The problem of exposure to low doses of radiation is being discussed in scientific literature for decades, but there is still no generally accepted conclusion concerning the existence of some features of the effect of low doses in contrast to that of acute exposure. This is due to the fact as follows: if being fixed, these effects have a weak expression and can be easily criticized. The second important aspect of this problem is that biological effects are mainly described phenomenologically in literature, without deciphering their molecular causes. In recent years, a number of articles appeared in which the authors, when studying exposure to low doses of DNA-tropic agents, show that postreplication repair (in particular, its error-free branch) plays a key role in these effects. In the laboratory of eukaryotic genetics of Petersburg Nuclear Physics Institute named by B. P. Konstantinov, it was possible to isolate unique yeast mutants with a disrupted branch of error-free postreplication repair. A study of the processes of eliminating DNA damage with minimal deviations of their number from a spontaneous level made it possible to explain at the molecular level the differences in cell response to low doses from acute exposure.

Carbon dioxide is widely used for a variety of purposes. As it is a normal constituent of air, the public generally regards it as safe. Although low concentrations of carbon dioxide are not harmful to human beings, high concentrations are toxic, and can cause serious harm, including cardiac arrest. Only a limited number of cases of carbon dioxide intoxication have been reported in Korea, and they have all been mild, with no cases of cardiac arrest following acute exposure to high concentrations of carbon dioxide, reported previously. We describe a case of carbon dioxide poisoning following an explosion of a carbon dioxide tank, which led to cardiac arrest in a 66-year-old patient. This cardiac arrest could have been avoided if the patient was fully aware of the hazardous effects and serious consequences of exposure to high concentrations of carbon dioxide.

Carr, Jay, Rachel Stone, Courtney Tymko, Kaitlyn Tymko, Geoff B. Coombs, Ryan L. Hoiland, Connor A. Howe, Michael M. Tymko, Philip N. Ainslie, and Alexander Patrician. Global REACH 2018: the effect...

Objetivo. Analizar la evidencia sobre la relación entre la contaminación del aire y un riesgo mayor de morbimortalidad por Covid-19. Material y métodos. Se utilizó una adaptación de la metodología de revisiones rápidas de Cochrane. La búsqueda se realizó en PubMed y MedRxiv y se limitó hasta el 28 y 26 de abril, respectivamente. Los títulos y resúmenes fueron revisados por cinco investigadores que, a su vez, revisaron los textos completos de la selección final. Resultados. Se encontraron 450 manuscritos, 15 cumplieron los criterios de inclusión. La evidencia encontrada reporta que la incidencia y el riesgo de morbilidad y mortalidad por Covid-19 se incrementan con la exposición crónica y aguda a la contaminación del aire, particularmente a material particulado (PM2.5, PM10) y dióxido de nitrógeno. Conclusiones. Se requieren más estudios especialmente en ciudades latinoamericanas. Es necesario fortalecer las recomendaciones en las ciudades con mayores niveles de contaminantes y reducir sus emisiones.

Contamination with polycyclic aromatic hydrocarbons (PAHs) causes noticeable ecological problems in aquatic ecosystems. 9,10-Phenanthrenequione (9,10-PQ) is an oxidized PAH and is highly toxic to aquatic animals. However, the effects of 9,10-PQ on the molecular metabolism of fish remain largely unknown. In this study, Takifugu obscurus juveniles were acutely exposed to 44.30 µg/L 9,10-PQ for 3 days. The transcriptome profile changes in their livers were compared between the 9,10-PQ treatment group and the control using T. rubripes as the reference genome. The results identified 22,414 genes in our transcriptome. Among them, 767 genes were differentially expressed after exposure to 9,10-PQ, which enriched 16 KEGG pathways. Among them, the glycolysis, phagosome, and FOXO signaling pathways were significantly activated in 9,10-PQ treatment compared with the control. These data indicate that 9,10-PQ increased the glycolysis capacity to produce more energy for resistance and harmed immune function. Moreover, several genes related to tumorigenesis were significantly upregulated in response to 9,10-PQ, displaying the carcinogenic toxicity of 9,10-PQ to T. obscurus. Genes in steroid biosynthesis pathways were downregulated in the 9,10-PQ treatment group, suggesting interference with the endocrine system. Overall, these findings provide information to help evaluate the environmental risks that oxygenated-PAHs present to T. obscurus.

Ambient air pollution (AAP) has been widely associated with increased morbidity of ischemic heart disease (IHD). However, no prior studies have investigated the effects of AAP exposure on the length of stay (LOS) due to IHD. Hospital data during 2015–2017 were obtained from hospital information system in five cities of Hubei province, China. We collected daily mean concentrations of air pollutants, including PM2.5, PM10, SO2, NO2, O3, and CO, and meteorological data during the same time period. Poisson regression was applied to estimate the acute impacts of AAP on the LOS of IHD inpatients. A total of 42,114 inpatients with primary diagnosis of IHD were included, 50.63% of which were chronic IHD inpatients. Annual average concentrations of PM2.5, PM10, SO2, NO2, O3, and CO were 61.93 μg/m3, 95.47 μg/m3, 18.59 μg/m3, 35.87 μg/m3, 100.30 μg/m3, and 1.117 mg/m3, respectively. After adjusting for temperature, relative humidity, gender, age group, payment method, number of hospital beds, location of hospital, and surgery or not, exposures to PM2.5, PM10, SO2, O3, and CO were associated with increased LOS for all IHD patients in both single- and multi-pollutant models, and stronger associations were observed among chronic IHD patients. In addition, subgroup analyses demonstrated that males and the group aged 65+ years were more vulnerable to air pollution, and the adverse effects were also promoted by low temperature in cold season. This study provides the first investigation of the adverse effects of AAP on the LOS for IHD patients. In order to shorten the LOS of IHD, measures should be taken to strengthen the AAP management and protect the high-risk population.

Air fresheners are widely used as a means of eliminating bad odour, albeit, it has been reported to be associated with some health risks. This work investigated the effect of acute exposure to air freshener on the antioxidant biomarkers of Wistar rats. Twenty-four Wistar rats were used for this study. The rats were divided into four groups of six rats each, labeled group 1, group 2, group 3, and group 4. Group 1, served as control which was not exposed to air freshener. Groups 2, 3 and 4 were exposed in a tightly enclosed cage to air freshener at 6, 9 and 12 h daily, respectively. The rats were sacrificed and blood collected in a sample bottle for analysis of the following antioxidants biomarkers; reduced glutathione (GSH), glutathione peroxidase (GPX), glutathione-S-transferase (GST), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase (CAT) after 14 and 28 days of exposure. The results showed that the blood MDA concentration increased significantly at p≤0.05 with increase in exposure time, a concurrent decrease in catalase and reduced glutathione concentration was observed significantly in the exposed groups when compared to the control. The decrease in SOD was concentration dependent, although not statistically significant, while an inconsistent decrease in the GPx and GST concentrations were observed in exposed groups when compared with the control group. These findings suggest that exposure to air freshener increased oxidative stress, thereby posing potential health hazards to the regular consumers. This study therefore suggests a reduction in exposure to air fresheners as its adverse health effect is proportional to the length of exposure. Key words: Air freshener, antioxidant, air pollution, oxidative stress.

This study assessed the hematological, enzymatic and osmoregulatory responses of silver catfish (Rhamdia quelen) exposed to sublethal concentrations (1.125 and 3.750 µg/L) of a commercial thiametho...

Aim To better understand the individual differences that make up a population, this study aimed to evaluate the effects of different alcoholic concentrations on the behavioral profiles of zebrafish (Danio rerio). Methods For this purpose, adult animals were separated into two behavioral profiles: bold and shy, according to the emergence order. Bold and shy fish were individually tested for exploration after exposure to the drug. Acute exposure treatments were alcohol 0.00, 0.10, 0.25 and 0.50%. The behavioral parameters evaluated were speed while moving, maximum speed, total distance traveled and distance from the bottom of the tank. Results For the groups that did not receive alcohol, bold animals showed higher speed while moving. Shy 0.00% and shy 0.10% had the highest maximum speed compared with other concentrations and profiles. For the distance from the bottom tank, our results showed that the increase induced by the low acute dose (0.10%) was observed for both profiles. Conclusions Our results corroborate with previous findings that alcohol affects the behavioral profiles of zebrafish differently, with bold animals apparently more resistant to these changes.

Background: Compared to day workers, shift workers face an elevated risk of cardiovascular disease. We reviewed the evidence to address the research question: Does acute exposure to shift work impact (blunt) the natural drop (dip) in Blood Pressure (BP) occurring during sleep and/or nighttime hours? (PROSPERO CRD42018110847). Methods: We performed a systematic review of five databases. We compared pooled estimates of mean BP stratified by periods of shift work, rest/leisure, and sleep, and evaluated the quality of evidence with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. Results: Our search covered 1/1/1980-10/24/2018 and yielded 1,636 records. Inter-rater agreement during screening was high (Kappa=0.87). We retained 44 studies described in 50 publications. We identified wide variation in shift worker type, shift schedules, and regularity of BP measurements. Most studies examined BP during one shift workday and one rest/leisure day. No study examined the impact of repeated exposure to shift work on the sleep-related dip in BP. Eighteen studies examined night shifts and one reported on BP during sleep post night shift. Compared to BP measured during shift work, BP measured during any sleep period separate from shift work was lower by 17.5 mmHg Systolic BP (95%CI 15.75, 19.27) and 15.4 mmHg lower for Diastolic BP (95%CI 14.38, 16.42) (p Conclusions: There is limited research exploring the acute and long-term impact of shift work on BP during sleep. The available evidence is heterogenous, low quality, and suggests that the mean dip in BP during sleep separate from shift work is not blunted.

This study was aimed at evaluating a potential association between blood pressure variation and acute mountain sickness (AMS) during acute exposure to normobaric hypoxia. A total of 77 healthy subjects (43 males, 34 females) were exposed to a simulated altitude of 4500 m for 12 hours. Peripheral oxygen saturation, heart rate, systemic blood pressure, and Lake Louise AMS scores were recorded before and during (30 minutes, 3, 6, 9, and 12 hours) hypoxic exposure. Blood pressure dips were observed at 3-hour mark. However, systolic blood pressure fell more pronounced from baseline during the initial 30 minutes in normobaric hypoxia (-17.5 vs. -11.0 mmHg

The depressive disorders remain one of the global problems of modern society. Many issues related to this topic remain open for discussion. It is reliably known that tropical fish Danio rerio (zebrafish) are the most studied and practical model methods of preclinical studies. They have several advantages over other laboratory animals. Danio Rerio is great for modeling stress and depression in order to identify the manifestations of medication to identify the manifestations of this condition. Methods. Danio Rerio when exposed to non-selective antidepressants and related serotonin reuptake inhibitors. Danio Rerio is under stress and depression due to acute exposure to caffeine and the subsequent use of antidepressants with timely recording and processing of the results. Results. The effect of sertraline on the Danio rerio group in order to identify the state of stress and depression was more effective in comparison with the results obtained using amitriptyline as an antidepressant. Conclusions. Sertraline in therapeutic concentration has a greater rate of elimination from anxiety and depression, which in turn allows us to argue about its greater effectiveness. In medical practice, it is better to prescribe drugs of the group of selective serotonin reuptake inhibitors in order to achieve a faster effect.

Current levels of Ultraviolet Radiation (UVR) represent a significant threat to many fish species. The first studies on the effects of UVR on organisms were performed on fish at the beginning of the twentieth century, and the topic has been progressing continuously until the present. Here, we review the reported harmful effects of ultraviolet B (UVB) and A (UVA) radiations in fish at different lifecycle stages, including embryo, larvae, juveniles and adults. The most evident negative effects during the early development stages are an increase in mortality and incidence in developmental malformations, with the skin and gills the most affected tissues in larvae. Growth reduction, a loss in body condition, and behavioral, physiological and metabolic changes in juveniles/adults occur under short- or long-term UVB exposure. The skin in juveniles/adults undergoes profound morphological and functional changes, even after acute exposure to UVR. Impairment of molecular and cellular processes was evidenced in all development stages by increasing the levels of DNA damage, apoptosis and changing tissues’ antioxidant status. The different photo-protective mechanisms to cope with excessive UVR exposure are also revised. Currently, stratospheric ozone dynamics and climate change interact strongly, enhancing the potential exposure of fish to UVR under water. Due to these environmental changes, fish are exposed to new and complex interactions between UVR and environmental stressors, which potentially affects fish growth and survival. Understanding the ability of fish to cope and adapt to these environmental changes will be essential to evaluate the potential impact in fisheries and mitigate ecological problems.

Background: Lymphatic vessels drain fluids and solutes from interstitial spaces and serosal cavities. Among the solutes, low-density lipoproteins (LDL) are drained and can be detected in peripheral...

Indo-Pacific lionfish (Pterois spp.) have become established throughout the Caribbean and the coastal regions of the Gulf of Mexico and western Atlantic Ocean from North Carolina to central Brazil. Lionfish may also invade estuaries, as they tolerate salinities down to 4‰. We hypothesize that the functional characteristics of their visual system (which evolved in the clear tropical waters of the Indo-Pacific) or their inability to tolerate hypoxia will limit the capacity of lionfish to occupy these areas. We assessed the former with corneal electroretinography and the latter with intermittent-flow respirometry. The luminous sensitivity, temporal resolution (quantified as flicker fusion frequency), and spectral sensitivity of the lionfish visual system are like those of native piscivores, indicating that their visual system will be functional under estuarine photic conditions and allow lionfish to be effective piscivores. In contrast, acute exposure to reduced oxygen levels (equivalent to those commonly occurring in mid-Atlantic and Gulf of Mexico estuaries) exceeded the physiological tolerances of lionfish. We therefore conclude that hypoxia will control or limit estuarine invasion.

Neonicotinoids are the most widely used insecticides worldwide, but there is mounting evidence demonstrating that they have adverse effects on nontarget organisms. However, little is known about the extent of environmental neonicotinoids contamination in China. In this study, a total of 693 honey samples from across China, from both Apis melifera and Apis cerana, were analyzed to examine neonicotinoid concentrations and their geographical distribution, and correlation with the primary plant species from which the honey was obtained. Furthermore, chronic and acute exposure risk and risk ranking for humans eating honey were investigated, and risks to bees were also considered. The results revealed that 40.8% of the samples contained at least one of the five neonicotinoids tested. Honeys from commercial crops were found to be more frequently contaminated with neonicotinoids than those from noncommercial crops. Honey samples from Apis mellifera were more frequently contaminated than those from Apis cerana. The concentrations of neonicotinoids found in honey overlapped with those that have been found to have significant adverse effects on honeybee health. The dietary risk assessments indicated that the levels of neonicotinoids detected in honey were likely to be safe for human consumption.

Animals that face unusual situations react instinctively in order to efficiently adapt to changes in the environment. Persistence leads training and learning the developed solution, which can then be applied to similar challenges in the future. We experimented on adult narrow-clawed crayfish extracted from both lentic and lotic habitats. We proved that the latter were more prone to grabbing objects during acute exposure to water currents. Chronic exposure of specimens from lentic habitat to water currents led to intense training in clumping activity, gripping quickly to adherent side objects regardless of the origin (natural or artificial). The behaviour was significantly reduced after the trained specimens were returned to an environment without water currents for a four-week period. The results suggest that crayfish can learn a solution when faced with a disturbance; once the disturbance disappeared, the trained response was no longer needed and lost.

Background Diesel exhaust fumes represent one of the most common toxic pollutants. The prolonged effects of acute exposure to this pollutant on inflammatory status and vascular properties are unknown. Methods During a 2-h session, 40 healthy subjects were exposed to diesel exhaust fumes and/or filtered air. Endothelial function was assessed with flow mediated dilation, arterial stiffness with pulse wave velocity and reflected waves with augmentation index. C-reactive protein, fibrinogen, protein C levels and protein S activity were also measured. Standard deviation of normal to normal R–R intervals (SDNN) was used to assess heart rate variability. Measurements were assessed before exposure and 2 and 24 h after diesel exposure. Results Compared with filtered air, exposure to diesel exhaust fumes decreased flow mediated dilation and increased pulse wave velocity and augmentation index up to 24 h after the exposure (p Conclusion Short-term exposure to diesel exhaust fumes has a prolonged adverse impact on endothelial function and vascular wall properties, along with impaired heart rate variability, abnormal fibrinolytic activity and increased markers of inflammation. These findings give insights into the mechanisms underlining the increased cardiovascular risk of subjects regularly exposed to diesel exhaust fumes.

In recent years, research in behavioral medicine has become increasingly focused on understanding how chronic and acute exposure to stress impacts health outcomes. During stress, the body’s physiological stress systems are activated. These systems closely interact with the immune system and are, thus, importantly implicated in the onset and maintenance of disease states. While much of the research in behavioral medicine that has investigated the effects of stress on disease has focused on the role of the hypothalamic-pituitary-adrenal axis and its downstream biomarker, cortisol, it is evident that the autonomic nervous system (ANS) also plays a crucial role in both the biological stress process and the manifestation and maintenance of stress-related symptoms. In recent years salivary alpha-amylase (sAA) has emerged as a valid and reliable marker of ANS activity in stress research and is therefore an important biomarker to consider in behavioral medicine. In this commentary, we will highlight research relevant for behavioral medicine that has utilized sAA measurements, both basally, and in response to stress, to examine ANS function in clinical populations. We will additionally summarize findings from studies that have examined the effects of various targeted interventions on changes in sAA levels. Through this, our aim is to present evidence that sAA can serve as a feasible biomarker of ANS (dys)function in health and disease. To this end, we will also highlight important methodological considerations for readers to keep in mind when including sAA assessments in their own studies. The overarching goal of this brief commentary is to highlight how a multidimensional approach toward physiological stress measurement can allow researchers to develop a better understanding of physical health and disease states.

Microbial fuel cells can be used as sensors to measure organic load (measured as biochemical oxygen demand; BOD) in aqueous waste streams, but electrical current output can also be affected by the presence of toxic compounds. Just as BOD is a non-specific measure of organic loading the toxic response is not differentiated for specific toxicants and thus enables a generalised toxicity level to be monitored. To date combined BOD and toxicity sensing with a MFC has not been possible without comparison with reference feeds of synthetic solutions, as a decrease in signal caused by a decrease in BOD could not be distinguished from those caused by the presence of a toxicant in the waste stream. In this work, an innovative solution using a three-stage MFC sensor configuration was developed to explicitly distinguish BOD-related and toxicity-related signal decrease. A decrease in BOD led to an initial responses in the third, followed by the second and first stage MFC. For a decrease from 360 to 60 mg L−1 O2 BOD5 the decrease in normalised current density was 59%, 82% and 94% in the first, second and third MFC respectively. In studies using 4-nitrophenol as a model toxic compound, increasing 4-nitrophenol concentrations resulted in an approximately equal decrease in current in all MFC in the MFC array (63%, 66% and 74% respectively when exposed to medium containing 150 mg L−1 4-nitrophenol). Thus the magnitude and ordering of the response allowed a decrease in signal from decreasing BOD to be distinguished from the presence of a toxic compound. Furthermore, the MFCs were capable of recovering to previous performance levels within hours of acute exposure to toxicity. The multi-stage MFC configuration therefore enabled truly combined BOD and toxicity sensing with enhanced detection capabilities without the need for a defined or synthetic reference feed.

This study explored the potential association between chronic exposure to pesticide mixtures including paraquat and respiratory outcomes among Colombian farmers. Sociodemographic and occupational data, respiratory symptoms and spirometric data were collected. Paraquat in spot urine samples were quantified with solid-phase extraction high-performance liquid chromatography. Multiple Poisson regressions with robust variance were used to determine factors associated with respiratory outcomes. Profiles of pesticide mixtures used were identified among 217 farmwork-ers, but profenofos and methamidophos-based mixtures were more frequent. Chronic paraquat exposure was slightly associated with self-reported asthma (PR: 1.06; 95% CI 1.00 to 1.13). Different pesticide mixtures were associated with flu, thoracic pain, allergic rhinitis, and obstructive pattern in spirometry. Although acute exposure to paraquat is low among Colombian farmers participating in the study, associations between respiratory outcomes and chronic pesticide mixtures exposure including profenofos, methamidophos or glyphosate require further specific studies. © 2020 National Institute of Occupational Safety and Health.

Introduction: Although both glucose and fructose are hexoses, their catabolism is quite different: the catabolism of fructose is initiated by ketohexokinase and is not regulated by negative feedback, which results in oxidative stress. Objective: We hypothesized that fructose impairs endothelium-dependent relaxation via oxidative stress in rat aortic rings. Methods: Sprague-Dawley rats were offered 20% fructose solution or tap water for 2 weeks, after which vascular reactivity was measured in isolated aortic rings. In a separate experiment, vascular reactivity was measured after acute exposure to ∼10 mM fructose in isolated aortic rings from untreated rats. Results: Although high-fructose intake statistically significantly increased blood pressure and body weight, it did not affect contraction and relaxation in aortic rings. The substitution of fructose for glucose in Krebs solution inhibited vascular relaxation in aortic rings, which was abolished by pretreatment with antioxidants. Decreasing the glucose concentration in Krebs solution inhibited vascular relaxation, whereas decreasing the fructose concentration in Krebs solution improved vascular relaxation in the aortic rings. Pretreatment with antioxidants improved the vascular relaxation in Krebs solution with fructose substituted for glucose. Conclusions: These results indicate that fructose impairs endothelium-dependent relaxation via oxidative stress in isolated rat aortic rings.

Diazinon is an organophosphate insecticide commonly used worldwide to chemically control different organisms considered as pests. In the past years, diazinon has been described to have immunotoxic effects in several species. Nile tilapia is a teleost fish with an ecological and economic importance, which is also one of the fishes with the highest consumption around the world. The aim of this study was to evaluate the production of neutrophil extracellular traps (NETs) from fish Nile tilapia (Oreochromis niloticus) exposed to diazinon (0.97, 1.95, and 3.91 mg/L) for 6 and 24 h. The results obtained indicate that the exposure to diazinon per se increases NETs production. Therefore, these results could be involved in the understanding of the inflammatory process induced by exposure to pesticides.

Zinc oxide nanoparticles (ZnO NPs) are extensively used for various products. In this study, the effects of ZnO NPs exposure in diversity and community composition of the bacteria associated with H. magnipapillata were investigated. This study provides insight into possible impacts of ZnO NPs on aquatic organisms. 454-pyrosequencing analysis of the bacterial 16S rRNA gene was applied to H. magnipapillata after exposure to 10 mg/L ZnO NPs (O 20 nm). Acute exposure to ZnO NPs changed the diversity and compositions of the associated bacteria. The composition of Curvibacter decreased, but Flectobacillus and Delftia increased; these two genera are known to have beneficial functions. The changes in diversity and composition of the associated bacteria may indicate the possible mechanisms by which the associated bacteria maintain their mutual interactions and support the health of their host after exposure to ZnO NPs.