Acute and chronic respiratory effects of sodium borate particulate exposures.

PubMed Central

Wegman, D H; Eisen, E A; Hu, X; Woskie, S R; Smith, R G; Garabrant, D H

1994-01-01

This study examined work-related chronic abnormality in pulmonary function and work-related acute irritant symptoms associated with exposure to borate dust in mining and processing operations. Chronic effects were examined by pulmonary function at the beginning and end of a 7-year interval. Time-specific estimates of sodium borate particulate exposures were used to estimate cumulative exposure during the study interval. Change in pulmonary function over the 7 years was found unrelated to the estimate of cumulative exposure during that interval. Exposure-response associations also were examined with respect to short-term peak exposures and incidence of five symptoms of acute respiratory irritation. Hourly measures of health outcome and continuous measures of particulate exposure were made on each subject throughout the day. Whenever a subject reported one of the irritant symptoms, a symptom intensity score was also recorded along with the approximate time of onset. The findings indicated that exposure-response relationships were present for each of the specific symptoms at several symptom intensity levels. The associations were present when exposure was estimated by both day-long and short-term (15-min) time-weighted average exposures. Associations persisted after taking account of smoking, age, and the presence of a common cold. No significant difference in response rate was found between workers exposed to different types of sodium borate dusts. PMID:7889871

Acute phase response, inflammation and metabolic syndrome biomarkers of Libby asbestos exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shannahan, Jonathan H.; Alzate, Oscar; Winnik, Witold M.

Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help elucidate epidemiologically-relevant biomarkers. In four experiments spanning varied protocols and temporality, healthy (Wistar Kyoto, WKY; and F344) and cardiovascular compromised (CVD) rat models (spontaneously hypertensive, SH; and SH heart failure, SHHF) were intratracheally instilled with saline (control) or LA. Serum biomarkers of cancer, inflammation, metabolic syndrome (MetS), and the acute phase response (APR) were analyzed. All rat strains exhibited acute increases inmore » α-2-macroglobulin, and α1-acid glycoprotein. Among markers of inflammation, lipocalin-2 was induced in WKY, SH and SHHF and osteopontin only in WKY after LA exposure. While rat strain- and age-related changes were apparent in MetS biomarkers, no LA effects were evident. The cancer marker mesothelin was increased only slightly at 1 month in WKY in one of the studies. Quantitative Intact Proteomic profiling of WKY serum at 1 day or 4 weeks after 4 weekly LA instillations indicated no oxidative protein modifications, however APR proteins were significantly increased. Those included serine protease inhibitor, apolipoprotein E, α-2-HS-glycoprotein, t-kininogen 1 and 2, ceruloplasmin, vitamin D binding protein, serum amyloid P, and more 1 day after last LA exposure. All changes were reversible after a short recovery regardless of the acute or long-term exposures. Thus, LA exposure induces an APR and systemic inflammatory biomarkers that could have implications in systemic and pulmonary disease in individuals exposed to LA. -- Highlights: ► Biomarkers of asbestos exposure are required for disease diagnosis. ► Libby amphibole exposure is associated with increased human mortality. ► Libby amphibole increases circulating proteins

Acute decrease in HDL cholesterol associated with exposure to welding fumes.

PubMed

Rice, Mary Berlik; Cavallari, Jenn; Fang, Shona; Christiani, David

2011-01-01

To investigate acute changes in circulating lipids after exposure to relatively high levels of particulate matter through welding. Using a repeated measures panel study, lipid levels before and after welding and personal exposures to fine particulate matter (PM2.5) were measured in 36 male welders over 63 exposure and/or control days. There was a trend toward decrease in HDL (-2.3 mg/dL, P = 0.08) 18 hours after welding. This effect became significant (-2.6 mg/dL, P = 0.05) after adjustment for possible confounders. The effect was strongest (-4.3 mg/dL, P = 0.02) among welders who did not weld the day before the study. There were no significant changes in other lipids associated with welding or PM2.5 exposure. Welding exposure was associated with an acute decrease in circulating HDL, which may relate to the inflammatory and proatherosclerotic effects of fine particle exposure.

Acute Decrease in HDL Cholesterol Associated With Exposure to Welding Fumes

PubMed Central

Rice, Mary Berlik; Cavallari, Jenn; Fang, Shona; Christiani, David

2011-01-01

Objective To investigate acute changes in circulating lipids after exposure to relatively high levels of particulate matter through welding. Methods Using a repeated measures panel study, lipid levels before and after welding and personal exposures to fine particulate matter (PM2.5) were measured in 36 male welders over 63 exposure and/or control days. Results There was a trend toward decrease in HDL (−2.3 mg/dL, P = 0.08) 18 hours after welding. This effect became significant (−2.6 mg/dL, P = 0.05) after adjustment for possible confounders. The effect was strongest (−4.3 mg/dL, P = 0.02) among welders who did not weld the day before the study. There were no significant changes in other lipids associated with welding or PM2.5 exposure. Conclusion Welding exposure was associated with an acute decrease in circulating HDL, which may relate to the inflammatory and proatherosclerotic effects of fine particle exposure. PMID:21187793

Leukemia risk associated with chronic external exposure to ionizing radiation in a French cohort of nuclear workers.

PubMed

Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

2012-11-01

Leukemia is one of the earliest cancer effects observed after acute exposure to relatively high doses of ionizing radiation. Leukemia mortality after external exposure at low doses and low-dose rates has been investigated at the French Atomic Energy Commission (CEA) and Nuclear Fuel Company (AREVA NC) after an additional follow-up of 10 years. The cohort included radiation-monitored workers employed for at least one year during 1950-1994 at CEA or AREVA NC and followed during 1968-2004. Association between external exposure and leukemia mortality was estimated with excess relative risk (ERR) models and time-dependent modifying factors were investigated with time windows. The cohort included 36,769 workers, followed for an average of 28 years, among whom 73 leukemia deaths occurred. Among the workers with a positive recorded dose, the mean cumulative external dose was 21.7 mSv. Results under a 2-year lag assumption suggested that the risk of leukemia (except chronic lymphatic leukemia) increased significantly by 8% per 10 mSv. The magnitude of the association for myeloid leukemia was larger. The higher ERR/Sv for doses received 2-14 years earlier suggest that time since exposure modifies the effect. The ERR/Sv also appeared higher for doses received at exposure rates ≥20 mSv per year. These results are consistent with those found in other studies of nuclear workers. However, confidence intervals are still wide. Further analyses should be conducted in pooled cohorts of nuclear workers.

Genome-wide Gene Expression Profiling of Acute Metal Exposures in Male Zebrafish

DTIC Science & Technology

2014-10-23

Data in Brief Genome-wide gene expression profiling of acute metal exposures in male zebrafish Christine E. Baer a,⁎, Danielle L. Ippolito b, Naissan... Zebrafish Whole organism Nickel Chromium Cobalt Toxicogenomics To capture global responses to metal poisoning and mechanistic insights into metal...toxicity, gene expression changes were evaluated in whole adult male zebrafish following acute 24 h high dose exposure to three metals with known human

Chronic vs. Short-Term Acute O 3 Exposure Effects on Nocturnal Transpiration in Two Californian Oaks

Treesearch

Nancy Grulke; E. Paoletti; R. L. Heath

2007-01-01

We tested the effect of daytime chronic moderate ozone (O3) exposure, short-term acute exposure, and both chronic and acute O3 exposure combined on nocturnal transpiration in California black oak and blue oak seedlings. Chronic O3 exposure (70 ppb for 8 h/day) was implemented in open-top chambers for...

Striatal dopamine dynamics in mice following acute and repeated toluene exposure.

PubMed

Apawu, Aaron K; Mathews, Tiffany A; Bowen, Scott E

2015-01-01

The abused inhalant toluene has potent behavioral effects, but only recently has progress been made in understanding the neurochemical actions that mediate the action of toluene in the brain. Available evidence suggests that toluene inhalation alters dopamine (DA) neurotransmission, but toluene's mechanism of action is unknown. The present study evaluated the effect of acute and repeated toluene inhalation (0, 2,000, or 4,000 ppm) on locomotor activity as well as striatal DA release and uptake using slice fast-scan cyclic voltammetry. Acutely, 2,000 and 4,000 ppm toluene increased locomotor activity, while neurochemically only 4,000 ppm toluene potentiated electrically evoked DA release across the caudate-putamen and the nucleus accumbens. Repeated administration of toluene resulted in sensitization to toluene's locomotor activity effects. Brain slices obtained from mice repeatedly exposed to toluene demonstrated no difference in stimulated DA release in the caudate-putamen as compared to control animals. Repeated exposure to 2,000 and 4,000 ppm toluene caused a concentration-dependent decrease of 25-50 % in evoked DA release in the nucleus accumbens core and shell relative to air-exposed mice. These voltammetric neurochemical findings following repeated toluene exposure suggest that there may be a compensatory downregulation of the DA system. Acute or repeated toluene exposure had no effect on the DA uptake kinetics. Taken together, these results demonstrate that acute toluene inhalation potentiates DA release, while repeated toluene exposure attenuates DA release in the nucleus accumbens only.

Nuclear accumulation of cyclin D1 following long-term fractionated exposures to low-dose ionizing radiation in normal human diploid cells

PubMed Central

Shimura, Tsutomu; Hamada, Nobuyuki; Sasatani, Megumi; Kamiya, Kenji; Kunugita, Naoki

2014-01-01

Cyclin D1 is a mitogenic sensor that responds to growth signals from the extracellular environment and regulates the G1-to-S cell cycle transition. When cells are acutely irradiated with a single dose of 10 Gy, cyclin D1 is degraded, causing cell cycle arrest at the G1/S checkpoint. In contrast, cyclin D1 accumulates in human tumor cells that are exposed to long-term fractionated radiation (0.5 Gy/fraction of X-rays). In this study we investigated the effect of fractionated low-dose radiation exposure on cyclin D1 localization in 3 strains of normal human fibroblasts. To specifically examine the nuclear accumulation of cyclin D1, cells were treated with a hypotonic buffer containing detergent to remove cytoplasmic cyclin D1. Proliferating cell nuclear antigen (PCNA) immunofluorescence was used to identify cells in S phase. With this approach, we observed S-phase nuclear retention of cyclin D1 following low-dose fractionated exposures, and found that cyclin D1 nuclear retention increased with exposure time. Cells that retained nuclear cyclin D1 were more likely to have micronuclei than non-retaining cells, indicating that the accumulation of nuclear cyclin D1 was associated with genomic instability. Moreover, inhibition of the v-akt murine thymoma viral oncogene homolog (AKT) pathway facilitated cyclin D1 degradation and eliminated cyclin D1 nuclear retention in cells exposed to fractionated radiation. Thus, cyclin D1 may represent a useful marker for monitoring long-term effects associated with exposure to low levels of radiation. PMID:24583467

Nuclear accumulation of cyclin D1 following long-term fractionated exposures to low-dose ionizing radiation in normal human diploid cells.

PubMed

Shimura, Tsutomu; Hamada, Nobuyuki; Sasatani, Megumi; Kamiya, Kenji; Kunugita, Naoki

2014-01-01

Cyclin D1 is a mitogenic sensor that responds to growth signals from the extracellular environment and regulates the G 1-to-S cell cycle transition. When cells are acutely irradiated with a single dose of 10 Gy, cyclin D1 is degraded, causing cell cycle arrest at the G 1/S checkpoint. In contrast, cyclin D1 accumulates in human tumor cells that are exposed to long-term fractionated radiation (0.5 Gy/fraction of X-rays). In this study we investigated the effect of fractionated low-dose radiation exposure on cyclin D1 localization in 3 strains of normal human fibroblasts. To specifically examine the nuclear accumulation of cyclin D1, cells were treated with a hypotonic buffer containing detergent to remove cytoplasmic cyclin D1. Proliferating cell nuclear antigen (PCNA) immunofluorescence was used to identify cells in S phase. With this approach, we observed S-phase nuclear retention of cyclin D1 following low-dose fractionated exposures, and found that cyclin D1 nuclear retention increased with exposure time. Cells that retained nuclear cyclin D1 were more likely to have micronuclei than non-retaining cells, indicating that the accumulation of nuclear cyclin D1 was associated with genomic instability. Moreover, inhibition of the v-akt murine thymoma viral oncogene homolog (AKT) pathway facilitated cyclin D1 degradation and eliminated cyclin D1 nuclear retention in cells exposed to fractionated radiation. Thus, cyclin D1 may represent a useful marker for monitoring long-term effects associated with exposure to low levels of radiation.

Comparison of Acute Health Effects From Exposures to Diesel and Biodiesel Fuel Emissions.

PubMed

Mehus, Aaron A; Reed, Rustin J; Lee, Vivien S T; Littau, Sally R; Hu, Chengcheng; Lutz, Eric A; Burgess, Jefferey L

2015-07-01

To investigate the comparative acute health effects associated with exposures to diesel and 75% biodiesel/25% diesel (B75) blend fuel emissions. We analyzed multiple health endpoints in 48 healthy adults before and after exposures to diesel and B75 emissions in an underground mine setting-lung function, lung and systemic inflammation, novel biomarkers of exposure, and oxidative stress were assessed. B75 reduced respirable diesel particulate matter by 20%. Lung function declined significantly more after exposure to diesel emissions. Lung inflammatory cells along with sputum and plasma inflammatory mediators increased significantly to similar levels with both exposures. Urinary 8-hydroxydeoxyguanosine, a marker of oxidative stress, was not significantly changed after either exposure. Use of B75 lowered respirable diesel particulate matter exposure and some associated acute health effects, although lung and systemic inflammation were not reduced compared with diesel use.

Acute respiratory symptoms and evacuation-related behavior after exposure to chlorine gas leakage.

PubMed

Han, Sung-Woo; Choi, Won-Jun; Yi, Min-Kee; Song, Seng-Ho; Lee, Dong-Hoon; Han, Sang-Hwan

2016-01-01

A study was performed on the accidental chlorine gas leakage that occurred in a factory of printed circuit boards manufactured without chlorine. Health examination was performed for all 52 workers suspected of exposure to chlorine gas, and their evacuation-related behaviors were observed in addition to analyzing the factors that affected the duration of their acute respiratory symptoms. Behavioral characteristics during the incidence of the accidental chlorine gas leakage, the estimated time of exposure, and the duration of subjective acute respiratory symptoms were investigated. In addition, clinical examination, chest radiography, and dental erosion test were performed. As variables that affected the duration of respiratory symptoms, dose group, body weight, age, sex, smoking, work period, and wearing a protective gear were included and analyzed by using the Cox proportional hazard model. Of 47 workers exposed to chlorine gas, 36 (77 %) developed more than one subjective symptom. The duration of the subjective symptoms according to exposure level significantly differed, with a median of 1 day (range, 0-5 days) in the low-exposure group and 2 days (range, 0-25 days) in the high-exposure group. Among the variables that affected the duration of the acute respiratory symptoms, which were analyzed by using the Cox proportional hazard model, only exposure level was significant (hazard ratio 2.087, 95 % CI = 1.119, 3.890). Regarding the evacuation-related behaviors, 22 workers (47 %) voluntarily evacuated to a safety zone immediately after recognizing the accidental exposure, but 25 workers (43 %) delayed evacuation until the start of mandatory evacuation (min 5, max 25 min). The duration of the subjective acute respiratory symptoms significantly differed between the low- and high-exposure groups. Among the 27 workers in the high-exposure group, 17 misjudged the toxicity after being aware of the gas leakage, which is a relatively high number.

Differences of acute versus chronic ethanol exposure on anxiety-like behavioral responses in zebrafish.

PubMed

Mathur, Priya; Guo, Su

2011-06-01

Zebrafish, a vertebrate model organism amenable to high throughput screening, is an attractive system to model and study the mechanisms underlying human diseases. Alcoholism and alcoholic medical disorders are among the most debilitating diseases, yet the mechanisms by which ethanol inflicts the disease states are not well understood. In recent years zebrafish behavior assays have been used to study learning and memory, fear and anxiety, and social behavior. It is important to characterize the effects of ethanol on zebrafish behavioral repertoires in order to successfully harvest the strength of zebrafish for alcohol research. One prominent effect of alcohol in humans is its effect on anxiety, with acute intermediate doses relieving anxiety and withdrawal from chronic exposure increasing anxiety, both of which have significant contributions to alcohol dependence. In this study, we assess the effects of both acute and chronic ethanol exposure on anxiety-like behaviors in zebrafish, using two behavioral paradigms, the Novel Tank Diving Test and the Light/Dark Choice Assay. Acute ethanol exposure exerted significant dose-dependent anxiolytic effects. However, withdrawal from repeated intermittent ethanol exposure disabled recovery from heightened anxiety. These results demonstrate that zebrafish exhibit different anxiety-like behavioral responses to acute and chronic ethanol exposure, which are remarkably similar to these effects of alcohol in humans. Because of the accessibility of zebrafish to high throughput screening, our results suggest that genes and small molecules identified in zebrafish will be of relevance to understand how acute versus chronic alcohol exposure have opposing effects on the state of anxiety in humans. Copyright © 2011 Elsevier B.V. All rights reserved.

Comparison of Acute Health Effects From Exposures to Diesel and Biodiesel Fuel Emissions

PubMed Central

Mehus, Aaron A.; Reed, Rustin J.; Lee, Vivien S. T.; Littau, Sally R.; Hu, Chengcheng; Lutz, Eric A.

2015-01-01

Objective: To investigate the comparative acute health effects associated with exposures to diesel and 75% biodiesel/25% diesel (B75) blend fuel emissions. Methods: We analyzed multiple health endpoints in 48 healthy adults before and after exposures to diesel and B75 emissions in an underground mine setting—lung function, lung and systemic inflammation, novel biomarkers of exposure, and oxidative stress were assessed. Results: B75 reduced respirable diesel particulate matter by 20%. Lung function declined significantly more after exposure to diesel emissions. Lung inflammatory cells along with sputum and plasma inflammatory mediators increased significantly to similar levels with both exposures. Urinary 8-hydroxydeoxyguanosine, a marker of oxidative stress, was not significantly changed after either exposure. Conclusions: Use of B75 lowered respirable diesel particulate matter exposure and some associated acute health effects, although lung and systemic inflammation were not reduced compared with diesel use. PMID:26147538

Cumulative exposure to prior collective trauma and acute stress responses to the Boston marathon bombings.

PubMed

Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

2015-06-01

The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. © The Author(s) 2015.

Radiation exposure and lung disease in today's nuclear world.

PubMed

Deas, Steven D; Huprikar, Nikhil; Skabelund, Andrew

2017-03-01

Ionizing radiation poses important health risks. The per capita annual dose rate has increased in the United States and there is increasing concern for the risks posed by low-dose occupational exposure among workers in nuclear industries and healthcare. Recent nuclear accidents and concern for terrorism have heightened concern for catastrophic, high-dose ionizing radiation exposure. This review will highlight recent research into the risks to lung health posed by ionizing radiation exposure and into potential treatments. Angiotensin-converting enzyme inhibitors and some antioxidants have shown promise as mitigators, to decrease pneumonitis and fibrosis when given after exposure. Studies of survivors of nuclear catastrophes have shown increased risk for lung cancer, especially in nonsmokers. There is evidence for increased lung cancer risk in industrial radiation workers, especially those who process plutonium and may inhale radioactive particles. There does not seem to be an increased risk of lung cancer in healthcare workers who perform fluoroscopic procedures. High-dose ionizing radiation exposure causes pneumonitis and fibrosis, and more research is needed to develop mitigators to improve outcomes in nuclear catastrophes. Long-term, low-dose occupational radiation may increase lung cancer risk. More research to better define this risk could lead to improved safety protocols and screening programs.

The brain is a target organ after acute exposure to depleted uranium.

PubMed

Lestaevel, P; Houpert, P; Bussy, C; Dhieux, B; Gourmelon, P; Paquet, F

2005-09-01

The health effects of depleted uranium (DU) are mainly caused by its chemical toxicity. Although the kidneys are the main target organs for uranium toxicity, uranium can also reach the brain. In this paper, the central effects of acute exposure to DU were studied in relation to health parameters and the sleep-wake cycle of adult rats. Animals were injected intraperitoneally with 144+/-10 microg DU kg-1 as nitrate. Three days after injection, the amounts of uranium in the kidneys represented 2.6 microg of DU g-1 of tissue, considered as a sub-nephrotoxic dosage. The central effect of uranium could be seen through a decrease in food intake as early as the first day after exposure and shorter paradoxical sleep 3 days after acute DU exposure (-18% of controls). With a lower dosage of DU (70+/-8 microg DU kg-1), no significant effect was observed on the sleep-wake cycle. The present study intends to illustrate the fact that the brain is a target organ, as are the kidneys, after acute exposure to a moderate dosage of DU. The mechanisms by which uranium causes these early neurophysiological perturbations shall be discussed.

Radiation exposure to sonographers from nuclear medicine patients: A review.

PubMed

Earl, Victoria Jean; Badawy, Mohamed Khaldoun

2018-06-01

Following nuclear medicine scans a patient can be a source of radiation exposure to the hospital staff, including sonographers. Sonographers are not routinely monitored for occupational radiation exposure as they do not commonly interact with radioactive patients or other sources of ionizing radiation. This review aims to find evidence relating to the risk and amount of radiation the sonographer is exposed to from nuclear medicine patients. It is established in the literature that the radiation exposure to the sonographer following diagnostic nuclear medicine studies is low and consequently the risk is not significant. Nevertheless, it is paramount that basic radiation safety principles are followed to ensure any exposure to ionizing radiation is kept as low as reasonably achievable. Practical recommendations are given to assist the sonographer in radiation protection. Nuclear medicine therapy procedures may place the sonographer at higher risk and as such consultation with a Radiation Safety Officer or Medical Physicist as to the extent of exposure is recommended. © 2018 The Royal Australian and New Zealand College of Radiologists.

EFFECTS OF ACUTE PYRETHROID EXPOSURE ON THERMOREGULATION IN RATS.

EPA Science Inventory

Pyrethroid insecticides produce acute neurotoxicity in mammals. According to the FQPA mandate, the USEPA is required to consider the risk of cumulative toxicity posed to humans through exposure to pyrethroid mixtures. Thermoregulatory response (TR) is being used to determine if t...

Self-Reported Acute Health Effects and Exposure to Companion Animals.

PubMed

Krueger, W S; Hilborn, E D; Dufour, A P; Sams, E A; Wade, T J

2016-06-01

To understand the etiological burden of disease associated with acute health symptoms [e.g. gastrointestinal (GI), respiratory, dermatological], it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar animals can result in a variety of health symptoms related to infection, irritation and allergy; however, few studies have examined this association in a large-scale cohort setting. Cross-sectional data collected from 50 507 participants in the United States enrolled from 2003 to 2009 were used to examine associations between animal contact and acute health symptoms during a 10-12 day period. Fixed-effects multivariable logistic regression estimated adjusted odds ratios (AORs) and 95% confident intervals (CI) for associations between animal exposures and outcomes of GI illness, respiratory illness and skin/eye symptoms. Two-thirds of the study population (63.2%) reported direct contact with animals, of which 7.7% had contact with at least one unfamiliar animal. Participants exposed to unfamiliar animals had significantly higher odds of self-reporting all three acute health symptoms, when compared to non-animal-exposed participants (GI: AOR = 1.4, CI = 1.2-1.7; respiratory: AOR = 1.5, CI = 1.2-1.8; and skin/eye: AOR = 1.9, CI = 1.6-2.3), as well as when compared to participants who only had contact with familiar animals. Specific contact with dogs, cats or pet birds was also significantly associated with at least one acute health symptom; AORs ranged from 1.1 to 1.5, when compared to participants not exposed to each animal. These results indicate that contact with animals, especially unfamiliar animals, was significantly associated with GI, respiratory and skin/eye symptoms. Such associations could be attributable to zoonotic infections and allergic reactions. Etiological models for acute health symptoms should consider contact with companion animals, particularly exposure to unfamiliar animals

[Acute risk assessment of cumulative dietary exposure to organophosphorus pesticide among people in Jiangsu province].

PubMed

Zhao, Minxian; Wang, Cannan; Li, Tingting; Yi, Nannan; He, Xiansong; Wu, Hui; Yao, Xinya

2013-09-01

To understand the cumulative dietary exposure of Jiangsu residents to organophosphorus (OPs) pesticide and make acute risk assessment. Integrated the data of the nutrition and health status of residents in Jiangsu and the data of monitoring of OPs pesticide in agricultural products. Chlorpyrifos was selected as index compound (index chemical, IC), then use relative potency factor (RPF) approach which commended by EPA and simple distribution evaluation. Caloulated the dietary cumulative exposure of OPs pesticide among Jiangsu residents and compared with acute reference dose (ARfD), then made risk assessment. The exposure of rural group of age 3-6 and 7-11 were 133.84 microg/kg BW and 154.32 microg/kg BW, exceeded ARfD. The exposure level of kids and elder was higher than adults. The exposure level of rural residents were higher than urban residents. The highest contribution to the food of each age group was greengrocery and leek. The average level of exposure was safety in Jiangsu, high exposure children were at acute poisoning risk. High contribution food such as greengrocery and leek should be strengthen monitoring.

Acute and chronic cold exposure differentially affects the browning of porcine white adipose tissue.

PubMed

Gao, Y; Qimuge, N R; Qin, J; Cai, R; Li, X; Chu, G Y; Pang, W J; Yang, G S

2018-07-01

Piglets are characteristically cold intolerant and thus susceptible to high mortality. However, browning of white adipose tissue (WAT) can induce non-shivering thermogenesis as a potential strategy to facilitate the animal's response to cold. Whether cold exposure can induce browning of subcutaneous WAT (sWAT) in piglets in a similar manner as it can in humans remains largely unknown. In this study, piglets were exposed to acute cold (4°C, 10 h) or chronic cold exposure (8°C, 15 days), and the genes and proteins of uncoupling protein 1 (UCP1)-dependent and independent thermogenesis, mitochondrial biogenesis, lipogenic and lipolytic processes were analysed. Interestingly, acute cold exposure induced browning of porcine sWAT, smaller adipocytes and the upregulated expression of UCP1, PGC1α, PGC1β, C/EBPβ, Cidea, UCP3, CKMT1 and PM20D1. Conversely, chronic cold exposure impaired the browning process, reduced mitochondrial numbers and the expression of browning markers, including UCP1, PGC1α and PRDM16. The present study demonstrated that acute cold exposure (but not chronic cold exposure) induces porcine sWAT browning. Thus, browning of porcine sWAT could be a novel strategy to balance the body temperature of piglets, and thus could be protective against cold exposure.

A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity

USGS Publications Warehouse

Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

2012-01-01

The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity.

PubMed

Lefebvre, Kathi A; Frame, Elizabeth R; Gulland, Frances; Hansen, John D; Kendrick, Preston S; Beyer, Richard P; Bammler, Theo K; Farin, Frederico M; Hiolski, Emma M; Smith, Donald R; Marcinek, David J

2012-01-01

The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

USE OF LETHALITY DATA DURING CATEGORICAL REGRESSION MODELING OF ACUTE REFERENCE EXPOSURES

EPA Science Inventory

Categorical regression is being considered by the U.S. EPA as an additional tool for derivation of acute reference exposures (AREs) to be used for human health risk assessment for exposure to inhaled chemicals. Categorical regression is used to calculate probability-response fun...

ACUTE EXPOSURE TO MOLINATE ALTERS NEUROENDOCRINE CONTROL OF OVULATION IN THE RAT

EPA Science Inventory

Molinate, a thiocarbamate herbicide, has been shown previously to impair reproductive capability in the male rat. In a two-generation study, molinate exposure to female rats resulted in altered pregnancy outcome. However, published data is lacking on the effects of acute exposure...

Steroid Exposure, Acute Coronary Syndrome, and Inflammatory Bowel Disease: Insights into the Inflammatory Milieu

PubMed Central

Deaño, Roderick C.; Basnet, Sandeep; Onandia, Zurine Galvan; Gandhi, Sachin; Tawakol, Ahmed; Min, James K.; Truong, Quynh A.

2014-01-01

Background Steroids are anti-inflammatory agents commonly used to treat inflammatory bowel disease. Inflammation plays a critical role in the pathophysiology of both inflammatory bowel disease and acute coronary syndrome. We examined the relationship between steroid use in patients with inflammatory bowel disease and acute coronary syndrome. Methods In 177 patients with inflammatory bowel disease (mean age 67, 75% male, 44% Crohn's disease, 56% ulcerative colitis), we performed a 1:2 case-control study matched for age, sex and inflammatory bowel disease type and compared 59 patients with inflammatory bowel disease with acute coronary syndrome to 118 patients with inflammatory bowel disease without acute coronary syndrome. Steroid use was defined as current or prior exposure. Acute coronary syndrome was defined as myocardial infarction or unstable angina, confirmed by cardiac biomarkers and coronary angiography. Results In patients with inflammatory bowel disease, 34% with acute coronary syndrome had exposure to steroids versus 58% without acute coronary syndrome (p<0.01). Steroid exposure reduced the adjusted odds of acute coronary syndrome by 82% (odds ratio [OR] 0.39, 95% CI 0.20-0.74; adjusted OR 0.18, 95% CI 0.06-0.51) in patients with inflammatory bowel disease, 77% in Crohn's disease (OR 0.36, 95% CI 0.14-0.92; adjusted OR 0.23, 95% CI 0.06-0.98), and 78% in ulcerative colitis (OR 0.41, 95% CI 0.16-1.04; adjusted OR 0.22, 95% CI 0.06-0.90). There was no association between other inflammatory bowel disease medications and acute coronary syndrome. Conclusions In patients with inflammatory bowel disease, steroid use significantly reduces the odds of acute coronary syndrome. These findings provide further mechanistic insight into the inflammatory processes involved in inflammatory bowel disease and acute coronary syndrome. PMID:25446295

Residential Exposure to Natural Background Radiation and Risk of Childhood Acute Leukemia in France, 1990–2009

PubMed Central

Demoury, Claire; Marquant, Fabienne; Ielsch, Géraldine; Goujon, Stéphanie; Debayle, Christophe; Faure, Laure; Coste, Astrid; Laurent, Olivier; Guillevic, Jérôme; Laurier, Dominique; Hémon, Denis; Clavel, Jacqueline

2016-01-01

Background: Exposures to high-dose ionizing radiation and high-dose rate ionizing radiation are established risk factors for childhood acute leukemia (AL). The risk of AL following exposure to lower doses due to natural background radiation (NBR) has yet to be conclusively determined. Methods: AL cases diagnosed over 1990–2009 (9,056 cases) were identified and their municipality of residence at diagnosis collected by the National Registry of Childhood Cancers. The Geocap study, which included the 2,763 cases in 2002–2007 and 30,000 population controls, was used for complementary analyses. NBR exposures were modeled on a fine scale (36,326 municipalities) based on measurement campaigns and geological data. The power to detect an association between AL and dose to the red bone marrow (RBM) fitting UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) predictions was 92%, 45% and 99% for exposure to natural gamma radiation, radon and total radiation, respectively. Results: AL risk, irrespective of subtype and age group, was not associated with the exposure of municipalities to radon or gamma radiation in terms of yearly exposure at age reached, cumulative exposure or RBM dose. There was no confounding effect of census-based socio-demographic indicators, or environmental factors (road traffic, high voltage power lines, vicinity of nuclear plants) related to AL in the Geocap study. Conclusions: Our findings do not support the hypothesis that residential exposure to NBR increases the risk of AL, despite the large size of the study, fine scale exposure estimates and wide range of exposures over France. However, our results at the time of diagnosis do not rule out a slight association with gamma radiation at the time of birth, which would be more in line with the recent findings in the UK and Switzerland. Citation: Demoury C, Marquant F, Ielsch G, Goujon S, Debayle C, Faure L, Coste A, Laurent O, Guillevic J, Laurier D, Hémon D, Clavel J

Acute and chronic ethanol exposure differentially alters alcohol dehydrogenase and aldehyde dehydrogenase activity in the zebrafish liver.

PubMed

Tran, Steven; Nowicki, Magda; Chatterjee, Diptendu; Gerlai, Robert

2015-01-02

Chronic ethanol exposure paradigms have been successfully used in the past to induce behavioral and central nervous system related changes in zebrafish. However, it is currently unknown whether chronic ethanol exposure alters ethanol metabolism in adult zebrafish. In the current study we examine the effect of acute ethanol exposure on adult zebrafish behavioral responses, as well as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in the liver. We then examine how two different chronic ethanol exposure paradigms (continuous and repeated ethanol exposure) alter behavioral responses and liver enzyme activity during a subsequent acute ethanol challenge. Acute ethanol exposure increased locomotor activity in a dose-dependent manner. ADH activity was shown to exhibit an inverted U-shaped curve and ALDH activity was decreased by ethanol exposure at all doses. During the acute ethanol challenge, animals that were continuously housed in ethanol exhibited a significantly reduced locomotor response and increased ADH activity, however, ALDH activity did not change. Zebrafish that were repeatedly exposed to ethanol demonstrated a small but significant attenuation of the locomotor response during the acute ethanol challenge but ADH and ALDH activity was similar to controls. Overall, we identified two different chronic ethanol exposure paradigms that differentially alter behavioral and physiological responses in zebrafish. We speculate that these two paradigms may allow dissociation of central nervous system-related and liver enzyme-dependent ethanol induced changes in zebrafish. Copyright © 2014 Elsevier Inc. All rights reserved.

Acute Exposure to Low-to-Moderate Carbon Dioxide Levels and Submariner Decision Making.

PubMed

Rodeheffer, Christopher D; Chabal, Sarah; Clarke, John M; Fothergill, David M

2018-06-01

Submarines routinely operate with higher levels of ambient carbon dioxide (CO2) (i.e., 2000 - 5000 ppm) than what is typically considered normal (i.e., 400 - 600 ppm). Although significant cognitive impairments are rarely reported at these elevated CO2 levels, recent studies using the Strategic Management Simulation (SMS) test have found impairments in decision-making performance during acute CO2 exposure at levels as low as 1000 ppm. This is a potential concern for submarine operations, as personnel regularly make mission-critical decisions that affect the safety and efficiency of the vessel and its crew while exposed to similar levels of CO2. The objective of this study was to determine if submariner decision-making performance is impacted by acute exposure to levels of CO2 routinely present in the submarine atmosphere during sea patrols. Using a subject-blinded balanced design, 36 submarine-qualified sailors were randomly assigned to receive 1 of 3 CO2 exposure conditions (600, 2500, or 15,000 ppm). After a 45-min atmospheric acclimation period, participants completed an 80-min computer-administered SMS test as a measure of decision making. There were no significant differences for any of the nine SMS measures of decision making between the CO2 exposure conditions. In contrast to recent research demonstrating cognitive deficits on the SMS test in students and professional-grade office workers, we were unable to replicate this effect in a submariner population-even with acute CO2 exposures more than an order of magnitude greater than those used in previous studies that demonstrated such effects.Rodeheffer CD, Chabal S, Clarke JM, Fothergill DM. Acute exposure to low-to-moderate carbon dioxide levels and submariner decision making. Aerosp Med Hum Perform. 2018; 89(6):520-525.

Human Physiological Responses to Acute and Chronic Cold Exposure

NASA Technical Reports Server (NTRS)

Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

2001-01-01

When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

Cardiac Autonomic Effects of Acute Exposures to Airborne Particulates in Men and Women

NASA Technical Reports Server (NTRS)

Howarth, M. S.; Schlegel, T. T.; Knapp, C. F.; Patwardhan, A. R.; Jenkins, R. A.; Ilgner, R. H.; Evans, J. M.

2007-01-01

The aim of this research was to investigate cardiac autonomic changes associated with acute exposures to airborne particulates. Methods: High fidelity 12-lead ECG (CardioSoft, Houston, TX) was acquired from 19 (10 male / 9 female) non-smoking volunteers (age 33.6 +/- 6.6 yrs) during 10 minutes pre-exposure, exposure and post-exposure to environmental tobacco smoke (ETS), cooking oil fumes, wood smoke and sham (water vapor). To control exposure levels, noise, subject activity, and temperature, all studies were conducted inside an environmental chamber. Results: The short-term fractal scaling exponent (Alpha-1) and the ratio of low frequency to high frequency Heart Rate Variability (HRV) powers (LF/HF, a purported sympathetic index) were both higher in males (p<0.017 and p<0.05, respectively) whereas approximate entropy (ApEn) and HF/(LF+HF) (a purported parasympathetic index) were both lower in males (p<0.036, and p<0.044, respectively). Compared to pre-exposure (p<0.0002) and sham exposure (p<0.047), male heart rates were elevated during early ETS post-exposure. Our data suggest that, in addition to tonic HRV gender differences, cardiac responses to some acute airborne particulates are gender related.

Inhibition of nuclear factor-κB signal by pyrrolidine dithiocarbamate alleviates lipopolysaccharide-induced acute lung injury

PubMed Central

Yang, Hongfu; Sun, Rongqing; Ma, Ning; Liu, Qilong; Sun, Xiaoge; Zi, Panpan; Wang, Junsheng; Chao, Ke; Yu, Lei

2017-01-01

This study mainly studied the effect of inhibition of nuclear factor-κB (NF-κB) signal by pyrrolidine dithiocarbamate (PDTC) on lipopolysaccharide (LPS)-induced inflammatory response, oxidative stress, and mitochondrial dysfunction in a murine acute lung injury model. The results showed that LPS exposure activated NF-κB and its upstream proteins and caused lung inflammation, oxidative stress, and mitochondrial dysfunction in mice. While inhibition of NF-κB by PDTC adminstration alleviated LPS-induced generation of lymphocytes, IL-1β, and TNF-α. Malondialdehyde, a common oxidative product, was markedly reduced after PDTC treatment in LPS-challenged mice. Furthermore, PDTC alleviated LPS-induced mitochondrial dysfunction via improving ATP synthesis and uncoupling protein 2 expression. In conclusion, inhibition of NF-κB by PDTC alleviated LPS-induced acute lung injury via maintaining inflammatory status, oxidative balance, and mitochondrial function in mice. PMID:28521300

Prior exposure to repeated immobilization or chronic unpredictable stress protects from some negative sequels of an acute immobilization.

PubMed

Pastor-Ciurana, Jordi; Rabasa, Cristina; Ortega-Sánchez, Juan A; Sanchís-Ollè, Maria; Gabriel-Salazar, Marina; Ginesta, Marta; Belda, Xavier; Daviu, Núria; Nadal, Roser; Armario, Antonio

2014-05-15

Exposure to chronic unpredictable stress (CUS) is gaining acceptance as a putative animal model of depression. However, there is evidence that chronic exposure to stress can offer non-specific stress protection from some effects of acute superimposed stressors. We then compared in adult male rats the protection afforded by prior exposure to CUS with the one offered by repeated immobilization on boards (IMO) regarding some of the negative consequences of an acute exposure to IMO. Repeated exposure to IMO protected from the negative consequences of an acute IMO on activity in an open-field, saccharin intake and body weight gain. Active coping during IMO (struggling) was markedly reduced by repeated exposure to the same stressor, but it was not affected by a prior history of CUS, suggesting that our CUS protocol does not appear to impair active coping responses. CUS exposure itself caused a strong reduction of activity in the open-field but appeared to protect from the hypo-activity induced by acute IMO. Moreover, prior CUS offered partial protection from acute IMO-induced reduction of saccharin intake and body weight gain. It can be concluded that a prior history of CUS protects from some of the negative consequences of exposure to a novel severe stressor, suggesting the development of partial cross-adaptation whose precise mechanisms remain to be studied. Copyright © 2014 Elsevier B.V. All rights reserved.

Chromosomal bands affected by acute oil exposure and DNA repair errors.

PubMed

Monyarch, Gemma; de Castro Reis, Fernanda; Zock, Jan-Paul; Giraldo, Jesús; Pozo-Rodríguez, Francisco; Espinosa, Ana; Rodríguez-Trigo, Gema; Verea, Hector; Castaño-Vinyals, Gemma; Gómez, Federico P; Antó, Josep M; Coll, Maria Dolors; Barberà, Joan Albert; Fuster, Carme

2013-01-01

In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk. We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency. Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin. Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016). The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.

Biomarkers of Acute Respiratory Allergen Exposure: Screening For Sensitization Potential

EPA Science Inventory

Rationale: An in vitro assay to identify respiratory sensitizers will provide a rapid screen and reduce animal use. The study goal was to identify biomarkers that differentiate allergen versus non-allergen responses following an acute exposure. Methods: Female BALB/c mice rec...

ACUTE BEHAVORIAL EFFECTS FROM EXPOSURE TO TWO-STROKE ENGINE EXHAUST

EPA Science Inventory

Benefits of changing from two-stroke to four-stroke engines (and other remedial requirements) can be evaluated (monetized) from the standpoint of acute behavioral effects of human exposure to exhaust from these engines. The monetization process depends upon estimates of the magn...

Cardiovascular effects of linalyl acetate in acute nicotine exposure.

PubMed

Kim, Ju Ri; Kang, Purum; Lee, Hui Su; Kim, Ka Young; Seol, Geun Hee

2017-04-24

Smoking is a risk factor for cardiovascular diseases as well as pulmonary dysfunction. In particular, adolescent smoking has been reported to have a higher latent risk for cardiovascular disease. Despite the risk to and vulnerability of adolescents to smoking, the mechanisms underlying the effects of acute nicotine exposure on adolescents remain unknown. This study therefore evaluated the mechanism underlying the effects of linalyl acetate on cardiovascular changes in adolescent rats with acute nicotine exposure. Parameters analyzed included heart rate (HR), systolic blood pressure, lactate dehydrogenase (LDH) activity, vascular contractility, and nitric oxide levels. Compared with nicotine alone, those treated with nicotine plus 10 mg/kg (p = 0.036) and 100 mg/kg (p = 0.023) linalyl acetate showed significant reductions in HR. Moreover, the addition of 1 mg/kg (p = 0.011), 10 mg/kg (p = 0.010), and 100 mg/kg (p = 0.011) linalyl acetate to nicotine resulted in significantly lower LDH activity. Nicotine also showed a slight relaxation effect, followed by a sustained recontraction phase, whereas nicotine plus linalyl acetate or nifedipine showed a constant relaxation effect on contraction of mouse aorta (p < 0.001). Furthermore, nicotine-induced increases in nitrite levels were decreased by treatment with linalyl acetate (p < 0.001). Taken together, our findings suggest that linalyl acetate treatment resulted in recovery of cell damage and cardiovascular changes caused by acute nicotine-induced cardiovascular disruption. Our evaluation of the influence of acute nicotine provides potential insights into the effects of environmental tobacco smoke and suggests linalyl acetate as an available mitigating agent.

Mitigation Strategies for Acute Radiation Exposure during Space Flight

NASA Technical Reports Server (NTRS)

Hamilton, Douglas R.; Epelman, Slava

2006-01-01

While there are many potential risks in a Moon or Mars mission, one of the most important and unpredictable is that of crew radiation exposure. The two forms of radiation that impact a mission far from the protective environment of low-earth orbit, are solar particle events (SPE) and galactic cosmic radiation (GCR). The effects of GCR occur as a long-term cumulative dose that results increased longer-term medical risks such as malignancy and neurological degeneration. Unfortunately, relatively little has been published on the medical management of an acute SPE that could potentially endanger the mission and harm the crew. Reanalysis of the largest SPE in August 1972 revealed that the dose rate was significantly higher than previously stated in the literature. The peak dose rate was 9 cGy h(sup -1) which exceeds the low dose-rate criteria for 25 hrs (National Council on Radiation Protection) and 16 hrs (United Nations Scientific Committee on the Effects of Atomic Radiation). The bone marrow dose accumulated was 0.8 Gy, which exceeded the 25 and 16 hour criteria and would pose a serious medical risk. Current spacesuits would not provide shielding from the damaging effects for an SPE as large as the 1972 event, as increased shielding from 1-5 grams per square centimeters would do little to shield the bone marrow from exposure. Medical management options for an acute radiation event are discussed based on recommendations from the Department of Homeland Security, Centers for Disease Control and evidence-based scientific literature. The discussion will also consider how to define acute exposure radiation safety limits with respect to exploration-class missions, and to determine the level of care necessary for a crew that may be exposed to an SPE similar to August 1972.

Limited inflammatory response in rats after acute exposure to a silicon carbide nanoaerosol

NASA Astrophysics Data System (ADS)

Laloy, J.; Lozano, O.; Alpan, L.; Masereel, B.; Toussaint, O.; Dogné, J. M.; Lucas, S.

2015-08-01

Inhalation represents the major route of human exposure to manufactured nanomaterials (NMs). Assessments are needed about the potential risks of NMs from inhalation on different tissues and organs, especially the respiratory tract. The aim of this limited study is to determine the potential acute pulmonary toxicity in rats exposed to a dry nanoaerosol of silicon carbide (SiC) nanoparticles (NPs) in a whole-body exposure (WBE) model. The SiC nanoaerosol is composed of a bimodal size distribution of 92.8 and 480 nm. The exposure concentration was 4.91 mg/L, close to the highest recommended concentration of 5 mg/L by the Organisation for Economic Co-operation and Development. Rats were exposed for 6 h to a stable and reproducible SiC nanoaerosol under real-time measurement conditions. A control group was exposed to the filtered air used to create the nanoaerosol. Animals were sacrificed immediately, 24 or 72 h after exposure. The bronchoalveolar lavage fluid from rat lungs was recovered. Macrophages filled with SiC NPs were observed in the rat lungs. The greatest load of SiC and macrophages filled with SiC were observed on the rat lungs sacrificed 24 h after acute exposure. A limited acute inflammatory response was found up to 24 h after exposure characterized by a lactate dehydrogenase and total protein increase or presence of inflammatory cells in pulmonary lavage. For this study a WBE model has been developed, it allows the simultaneous exposure of six rats to a nanoaerosol and six rats to clean-filtered air. The nanoaerosol was generated using a rotating brush system (RBG-1000) and analyzed with an electrical low pressure impactor in real time.

Effects of acute ethanol exposure on cytokine production by primary airway smooth muscle cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaphalia, Lata; Kalita, Mridul; Kaphalia, Bhupendra S.

Both chronic and binge alcohol abuse can be significant risk factors for inflammatory lung diseases such as acute respiratory distress syndrome and chronic obstructive pulmonary disease. However, metabolic basis of alcohol-related lung disease is not well defined, and may include key metabolites of ethanol [EtOH] in addition to EtOH itself. Therefore, we investigated the effects of EtOH, acetaldehyde [ACE], and fatty acid ethyl esters [FAEEs] on oxidative stress, endoplasmic reticulum (ER) stress, AMP-activated protein kinase (AMPK) signaling and nuclear translocation of phosphorylated (p)-NF-κB p65 in primary human airway smooth muscle (HASM) cells stimulated to produce cytokines using LPS exposure. Bothmore » FAEEs and ACE induced evidence of cellular oxidative stress and ER stress, and increased p-NF-κB in nuclear extracts. EtOH and its metabolites decreased p-AMPKα activation, and induced expression of fatty acid synthase, and decreased expression of sirtuin 1. In general, EtOH decreased secretion of IP-10, IL-6, eotaxin, GCSF, and MCP-1. However, FAEEs and ACE increased these cytokines, suggesting that both FAEEs and ACE as compared to EtOH itself are proinflammatory. A direct effect of EtOH could be consistent with blunted immune response. Collectively, these two features of EtOH exposure, coupled with the known inhibition of innate immune response in our model might explain some clinical manifestations of EtOH exposure in the lung. - Highlights: • Metabolic basis for EtOH toxicity was studied in human airway smooth muscle (HASM) cells. • In HASM cells, EtOH metabolites were found to be relatively more toxic than EtOH itself. • EtOH metabolites mediate deactivation of AMPK via oxidative stress and ER stress. • EtOH metabolites were found to be more proinflammatory than EtOH itself in HASM cells.« less

Case-control study of childhood acute lymphoblastic leukemia and residential radon exposure.

PubMed

Lubin, J H; Linet, M S; Boice, J D; Buckley, J; Conrath, S M; Hatch, E E; Kleinerman, R A; Tarone, R E; Wacholder, S; Robison, L L

1998-02-18

Several ecologic analyses have shown significant positive associations between mean indoor radon concentrations and risk of leukemia at all ages (acute myeloid leukemia and chronic lymphocytic leukemia) and for children (all leukemia, acute myeloid leukemia, and acute lymphoblastic leukemia [ALL]). As part of an age-matched, case-control study of childhood ALL in the United States, we investigated the association between the incidence of ALL in children under age 15 years and indoor radon exposure. Radon detectors were placed in current and previous homes of subjects where they resided for 6 months or longer. Children were included in analyses if radon measurements covered 70% or more of the 5-year period prior to diagnosis for case subjects (or from birth for case subjects under age 5 years) and the corresponding reference dates for control subjects. Radon levels could be estimated for 97% of the exposure period for the eligible 505 case subjects and 443 control subjects. Mean radon concentration was lower for case subjects (65.4 becquerels per cubic meter [Bqm(-3)]) than for control subjects (79.1 Bqm(-3)). For categories less than 37, 37-73, 74-147, and 148 or more Bqm(-3) of radon exposure, relative risks based on matched case-control pairs were 1.00, 1.22, 0.82, and 1.02, respectively, and were similar to results from an unmatched analysis. There was no association between ALL and radon exposure within subgroups defined by categories of age, income, birth order, birth weight, sex, type of residence, magnetic field exposure, parental age at the subject's birth, parental occupation, or parental smoking habits. In contrast to prior ecologic studies, the results from this analytic study provide no evidence for an association between indoor radon exposure and childhood ALL.

Self-reported acute health symptoms and exposure to companion animals#

EPA Science Inventory

Self-reported acute health symptoms and exposure to companion animalsWhitney S. Krueger1,2, Elizabeth D. Hilborn2, Timothy J. Wade21Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA2Environmental Public Health Division, Office of Research and Development, U...

Acute illness-induced behavioral alterations are similar to those observed during withdrawal from acute alcohol exposure

PubMed Central

Richey, Laura; Doremus-Fitzwater, Tamara L.; Buck, Hollin M.; Deak, Terrence

2012-01-01

Exposure to an immunogen results in a constellation of behavioral changes collectively referred to as “sickness behaviors,” with alterations in cytokine expression previously shown to contribute to this sickness response. Since behaviors observed during ethanol withdrawal are strikingly similar to sickness behaviors, we hypothesized that behavioral manifestations of ethanol withdrawal might be an expression of sickness behaviors induced by ethanol-related changes in peripheral and/or central cytokine expression. Accordingly, behaviors exhibited during a modified social investigation test were first characterized in male rats following an acute injection of lipopolysaccharide (LPS; 100 μg/kg). Subsequently, behavioral changes after either a high (4-g/kg; Experiment 2) or low dose (0.5 g/kg; Experiment 3) of ethanol were also examined in the same social investigation test, as well as in the forced-swim test (FST; Experiment 4). Results from these experiments demonstrated similar reductions in both exploration and social investigatory behavior during acute illness and ethanol withdrawal, while a seemingly paradoxical decrease in immobility was observed in the FST during acute ethanol withdrawal. In follow-up studies, neither indomethacin (Experiment 5) nor interleukin-1 receptor antagonist (Experiment 6) pre-exposure reversed the ethanol withdrawal-induced behavioral changes observed in this social investigation test. Taken together, these studies demonstrate that the behavioral sequelae of acute illness and ethanol withdrawal are similar in nature, while antagonist studies suggest that these behavioral alterations are not reversed by blockade of IL-1 receptors or inhibition of prostaglandin synthesis. Though a direct mechanistic link between cytokines and the expression of acute ethanol withdrawal-related behaviors has yet to be found, future studies examining the involvement of brain cytokines as potential mediators of ethanol effects are greatly needed. PMID

Neurobehavorial effects of acute exposure to four solvents: meta-abalyses

EPA Science Inventory

Meta-and re-analyses of the available data for the neurobehavioral effects of acute inhalation exposure to toluene were reported by Benignus et al. (2007). The present study was designed to test the generality of the toluene results in as many other solvents as possible by furthe...

Acute lead exposure increases arterial pressure: role of the renin-angiotensin system.

PubMed

Simões, Maylla Ronacher; Ribeiro Júnior, Rogério F; Vescovi, Marcos Vinícius A; de Jesus, Honério C; Padilha, Alessandra S; Stefanon, Ivanita; Vassallo, Dalton V; Salaices, Mercedes; Fioresi, Mirian

2011-04-11

Chronic lead exposure causes hypertension and cardiovascular disease. Our purpose was to evaluate the effects of acute exposure to lead on arterial pressure and elucidate the early mechanisms involved in the development of lead-induced hypertension. Wistar rats were treated with lead acetate (i.v. bolus dose of 320 µg/Kg), and systolic arterial pressure, diastolic arterial pressure and heart rate were measured during 120 min. An increase in arterial pressure was found, and potential roles of the renin-angiotensin system, Na(+),K(+)-ATPase and the autonomic reflexes in this change in the increase of arterial pressure found were evaluated. In anesthetized rats, lead exposure: 1) produced blood lead levels of 37±1.7 µg/dL, which is below the reference blood concentration (60 µg/dL); 2) increased systolic arterial pressure (Ct: 109±3 mmHg vs Pb: 120±4 mmHg); 3) increased ACE activity (27% compared to Ct) and Na(+),K(+)-ATPase activity (125% compared to Ct); and 4) did not change the protein expression of the α1-subunit of Na(+),K(+)-ATPase, AT(1) and AT(2). Pre-treatment with an AT(1) receptor blocker (losartan, 10 mg/Kg) or an ACE inhibitor (enalapril, 5 mg/Kg) blocked the lead-induced increase of arterial pressure. However, a ganglionic blockade (hexamethonium, 20 mg/Kg) did not prevent lead's hypertensive effect. Acute exposure to lead below the reference blood concentration increases systolic arterial pressure by increasing angiotensin II levels due to ACE activation. These findings offer further evidence that acute exposure to lead can trigger early mechanisms of hypertension development and might be an environmental risk factor for cardiovascular disease.

Acute Illness Among Surfers After Exposure to Seawater in Dry- and Wet-Weather Conditions

PubMed Central

Arnold, Benjamin F.; Schiff, Kenneth C.; Ercumen, Ayse; Benjamin-Chung, Jade; Steele, Joshua A.; Griffith, John F.; Steinberg, Steven J.; Smith, Paul; McGee, Charles D.; Wilson, Richard; Nelsen, Chad; Colford, John M.

2017-01-01

Abstract Rainstorms increase levels of fecal indicator bacteria in urban coastal waters, but it is unknown whether exposure to seawater after rainstorms increases rates of acute illness. Our objective was to provide the first estimates of rates of acute illness after seawater exposure during both dry- and wet-weather periods and to determine the relationship between levels of indicator bacteria and illness among surfers, a population with a high potential for exposure after rain. We enrolled 654 surfers in San Diego, California, and followed them longitudinally during the 2013–2014 and 2014–2015 winters (33,377 days of observation, 10,081 surf sessions). We measured daily surf activities and illness symptoms (gastrointestinal illness, sinus infections, ear infections, infected wounds). Compared with no exposure, exposure to seawater during dry weather increased incidence rates of all outcomes (e.g., for earache or infection, adjusted incidence rate ratio (IRR) = 1.86, 95% confidence interval (CI): 1.27, 2.71; for infected wounds, IRR = 3.04, 95% CI: 1.54, 5.98); exposure during wet weather further increased rates (e.g., for earache or infection, IRR = 3.28, 95% CI: 1.95, 5.51; for infected wounds, IRR = 4.96, 95% CI: 2.18, 11.29). Fecal indicator bacteria measured in seawater (Enterococcus species, fecal coliforms, total coliforms) were strongly associated with incident illness only during wet weather. Urban coastal seawater exposure increases the incidence rates of many acute illnesses among surfers, with higher incidence rates after rainstorms. PMID:28498895

Casualty Estimation for Nuclear and Radiological Weapons

DTIC Science & Technology

2016-06-01

usually defined as energy deposited (joule) per unit of mass (kilogram). See gray and rad. Acute Radiation Syndrome (ARS): ARS is a serious illness...I-2 ARS Acute Radiation Syndrome BSA body surface area CBRN chemical, biological, radiological, and nuclear CONV convalescent CUT cutaneous DOW...include acute effects, which may result from internal or external radiation exposure. The severity of these effects is directly related to the dosage

A Mathematical Model of the Human Small Intestine Following Acute Radiation and Burn Exposures

DTIC Science & Technology

2016-08-01

Acronyms and Symbols ARA Applied Research Associates, Inc. ARS Acute radiation syndrome d Days DE Differential Evolution DTRA Defense Threat...04-08-2016 Technical Report A Mathematical Model of the Human Small Intestine Following Acute Radiation and Burn Exposures HDTRA1...epithelial cells to acute radiation alone. The model has been modified for improved radiation response, and an addition to the model allows for thermal injury

Acute effects of cigarette smoke exposure on experimental skin flaps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nolan, J.; Jenkins, R.A.; Kurihara, K.

1985-04-01

Random vascular patterned caudally based McFarlane-type skin flaps were elevated in groups of Fischer 344 rats. Groups of rats were then acutely exposed on an intermittent basis to smoke generated from well-characterized research filter cigarettes. Previously developed smoke inhalation exposure protocols were employed using a Maddox-ORNL inhalation exposure system. Rats that continued smoke exposure following surgery showed a significantly greater mean percent area of flap necrosis compared with sham-exposed groups or control groups not exposed. The possible pathogenesis of this observation as well as considerations and correlations with chronic human smokers are discussed. Increased risks of flap necrosis by smokingmore » in the perioperative period are suggested by this study.« less

Residential Exposure to Natural Background Radiation and Risk of Childhood Acute Leukemia in France, 1990-2009.

PubMed

Demoury, Claire; Marquant, Fabienne; Ielsch, Géraldine; Goujon, Stéphanie; Debayle, Christophe; Faure, Laure; Coste, Astrid; Laurent, Olivier; Guillevic, Jérôme; Laurier, Dominique; Hémon, Denis; Clavel, Jacqueline

2017-04-01

Exposures to high-dose ionizing radiation and high-dose rate ionizing radiation are established risk factors for childhood acute leukemia (AL). The risk of AL following exposure to lower doses due to natural background radiation (NBR) has yet to be conclusively determined. AL cases diagnosed over 1990-2009 (9,056 cases) were identified and their municipality of residence at diagnosis collected by the National Registry of Childhood Cancers. The Geocap study, which included the 2,763 cases in 2002-2007 and 30,000 population controls, was used for complementary analyses. NBR exposures were modeled on a fine scale (36,326 municipalities) based on measurement campaigns and geological data. The power to detect an association between AL and dose to the red bone marrow (RBM) fitting UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) predictions was 92%, 45% and 99% for exposure to natural gamma radiation, radon and total radiation, respectively. AL risk, irrespective of subtype and age group, was not associated with the exposure of municipalities to radon or gamma radiation in terms of yearly exposure at age reached, cumulative exposure or RBM dose. There was no confounding effect of census-based socio-demographic indicators, or environmental factors (road traffic, high voltage power lines, vicinity of nuclear plants) related to AL in the Geocap study. Our findings do not support the hypothesis that residential exposure to NBR increases the risk of AL, despite the large size of the study, fine scale exposure estimates and wide range of exposures over France. However, our results at the time of diagnosis do not rule out a slight association with gamma radiation at the time of birth, which would be more in line with the recent findings in the UK and Switzerland.

Exposure to acute stress enhances decision-making competence: Evidence for the role of DHEA.

PubMed

Shields, Grant S; Lam, Jovian C W; Trainor, Brian C; Yonelinas, Andrew P

2016-05-01

Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol. Copyright © 2016 Elsevier Ltd. All rights reserved.

Exposure to Acute Stress Enhances Decision-Making Competence: Evidence for the Role of DHEA

PubMed Central

Shields, Grant S.; Lam, Jovian C. W.; Trainor, Brian C.; Yonelinas, Andrew P.

2016-01-01

Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol. PMID:26874561

Nuclear DNA as Predictor of Acute Kidney Injury in Patients Undergoing Coronary Artery Bypass Graft: A Pilot Study.

PubMed

Likhvantsev, Valery V; Landoni, Giovanni; Grebenchikov, Oleg A; Skripkin, Yuri V; Zabelina, Tatiana S; Zinovkina, Liudmila A; Prikhodko, Anastasia S; Lomivorotov, Vladimir V; Zinovkin, Roman A

2017-12-01

To measure the release of plasma nuclear deoxyribonucleic acid (DNA) and to assess the relationship between nuclear DNA level and acute kidney injury occurrence in patients undergoing cardiac surgery. Cardiovascular anesthesiology and intensive care unit of a large tertiary-care university hospital. Prospective observational study. Fifty adult patients undergoing cardiac surgery. Nuclear DNA concentration was measured in the plasma. The relationship between the level of nuclear DNA and the incidence of acute kidney injury after coronary artery bypass grafting was investigated. Cardiac surgery leads to significant increase in plasma nuclear DNA with peak levels 12 hours after surgery (median [interquartile range] 7.0 [9.6-22.5] µg/mL). No difference was observed between off-pump and on-pump surgical techniques. Nuclear DNA was the only predictor of acute kidney injury between baseline and early postoperative risk factors. The authors found an increase of nuclear DNA in the plasma of patients who had undergone coronary artery bypass grafting, with a peak after 12 hours and an association of nuclear DNA with postoperative acute kidney injury. Copyright © 2017 Elsevier Inc. All rights reserved.

Acute Illness Among Surfers After Exposure to Seawater in Dry- and Wet-Weather Conditions.

PubMed

Arnold, Benjamin F; Schiff, Kenneth C; Ercumen, Ayse; Benjamin-Chung, Jade; Steele, Joshua A; Griffith, John F; Steinberg, Steven J; Smith, Paul; McGee, Charles D; Wilson, Richard; Nelsen, Chad; Weisberg, Stephen B; Colford, John M

2017-10-01

Rainstorms increase levels of fecal indicator bacteria in urban coastal waters, but it is unknown whether exposure to seawater after rainstorms increases rates of acute illness. Our objective was to provide the first estimates of rates of acute illness after seawater exposure during both dry- and wet-weather periods and to determine the relationship between levels of indicator bacteria and illness among surfers, a population with a high potential for exposure after rain. We enrolled 654 surfers in San Diego, California, and followed them longitudinally during the 2013-2014 and 2014-2015 winters (33,377 days of observation, 10,081 surf sessions). We measured daily surf activities and illness symptoms (gastrointestinal illness, sinus infections, ear infections, infected wounds). Compared with no exposure, exposure to seawater during dry weather increased incidence rates of all outcomes (e.g., for earache or infection, adjusted incidence rate ratio (IRR) = 1.86, 95% confidence interval (CI): 1.27, 2.71; for infected wounds, IRR = 3.04, 95% CI: 1.54, 5.98); exposure during wet weather further increased rates (e.g., for earache or infection, IRR = 3.28, 95% CI: 1.95, 5.51; for infected wounds, IRR = 4.96, 95% CI: 2.18, 11.29). Fecal indicator bacteria measured in seawater (Enterococcus species, fecal coliforms, total coliforms) were strongly associated with incident illness only during wet weather. Urban coastal seawater exposure increases the incidence rates of many acute illnesses among surfers, with higher incidence rates after rainstorms. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Acute effects of exposure to 56Fe and 16O particles on learning and memory

USDA-ARS?s Scientific Manuscript database

Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles can exert acute effects on cognitive performance; i.e., effects within 4-48 hrs after exposure. The present ...

The alteration of spontaneous low frequency oscillations caused by acute electromagnetic fields exposure.

PubMed

Lv, Bin; Chen, Zhiye; Wu, Tongning; Shao, Qing; Yan, Duo; Ma, Lin; Lu, Ke; Xie, Yi

2014-02-01

The motivation of this study is to evaluate the possible alteration of regional resting state brain activity induced by the acute radiofrequency electromagnetic field (RF-EMF) exposure (30min) of Long Term Evolution (LTE) signal. We designed a controllable near-field LTE RF-EMF exposure environment. Eighteen subjects participated in a double-blind, crossover, randomized and counterbalanced experiment including two sessions (real and sham exposure). The radiation source was close to the right ear. Then the resting state fMRI signals of human brain were collected before and after the exposure in both sessions. We measured the amplitude of low frequency fluctuation (ALFF) and fractional ALFF (fALFF) to characterize the spontaneous brain activity. We found the decreased ALFF value around in left superior temporal gyrus, left middle temporal gyrus, right superior temporal gyrus, right medial frontal gyrus and right paracentral lobule after the real exposure. And the decreased fALFF value was also detected in right medial frontal gyrus and right paracentral lobule. The study provided the evidences that 30min LTE RF-EMF exposure modulated the spontaneous low frequency fluctuations in some brain regions. With resting state fMRI, we found the alteration of spontaneous low frequency fluctuations induced by the acute LTE RF-EMF exposure. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Carryover Effects of Acute DEHP Exposure on Ovarian Function and Oocyte Developmental Competence in Lactating Cows

PubMed Central

Kalo, Dorit; Hadas, Ron; Furman, Ori; Ben-Ari, Julius; Maor, Yehoshua; Patterson, Donald G.; Tomey, Cynthia; Roth, Zvi

2015-01-01

We examined acute exposure of Holstein cows to di(2-ethylhexyl) phthalate (DEHP) and its carryover effects on ovarian function and oocyte developmental competence. Synchronized cows were tube-fed with water or 100 mg/kg DEHP per day for 3 days. Blood, urine and milk samples were collected before, during and after DEHP exposure to examine its clearance pattern. Ovarian follicular dynamics was monitored through an entire estrous cycle by ultrasonographic scanning. Follicular fluids were aspirated from the preovulatory follicles on days 0 and 29 of the experiment and analyzed for phthalate metabolites and estradiol concentration. The aspirated follicular fluid was used as maturation medium for in-vitro embryo production. Findings revealed that DEHP impairs the pattern of follicular development, with a prominent effect on dominant follicles. The diameter and growth rate of the first- and second-wave dominant follicles were lower (P < 0.05) in the DEHP-treated group. Estradiol concentration in the follicular fluid was lower in the DEHP-treated group than in controls, and associated with a higher number of follicular pathologies (follicle diameter >25 mm). The pattern of growth and regression of the corpus luteum differed between groups, with a lower volume in the DEHP-treated group (P < 0.05). The follicular fluid aspirated from the DEHP-treated group, but not the controls, contained 23 nM mono(2-ethylhexyl) phthalate. Culturing of cumulus oocyte complexes in the follicular fluid aspirated from DEHP-treated cows reduced the proportion of oocytes progressing to the MII stage, and the proportions of 2- to 4-cell-stage embryos (P < 0.04) and 7-day blastocysts (P < 0.06). The results describe the risk associated with acute exposure to DEHP and its deleterious carryover effects on ovarian function, nuclear maturation and oocyte developmental competence. PMID:26154164

Neuromotor effects of acute ethanol inhalation exposure in humans: a preliminary study.

PubMed

Nadeau, Véronique; Lamoureux, Daniel; Beuter, Anne; Charbonneau, Michel; Tardif, Robert

2003-07-01

Ethanol (ETOH) is added to unleaded gasoline to decrease environmental levels of carbon monoxide from automobiles emissions. Therefore, addition of ETOH in reformulated fuel will most likely increase and the involuntarily human exposure to this chemical will also increase. This preliminary study was undertaken to evaluate the possible neuromotor effects resulting from acute ETOH exposure by inhalation in humans. Five healthy non-smoking adult males, with no history of alcohol abuse, were exposed by inhalation, in a dynamic, controlled-environment exposure chamber, to various concentrations of ETOH (0, 250, 500 and 1,000 ppm in air) for six hours. Reaction time, body sway, hand tremor and rapid alternating movements were measured before and after each exposure session by using the CATSYS 7.0 system and a diadochokinesimeter. The concentrations of ETOH in blood and in alveolar air were also measured. ETOH was not detected in blood nor in alveolar air when volunteers were exposed to 250 and 500 ppm, but at the end of exposure to 1,000 ppm, blood and alveolar air concentrations were 0.443 mg/100ml and 253.1 ppm, respectively. The neuromotor tests did not show conclusively significant differences between the exposed and non-exposed conditions. In conclusion, this study suggests that acute exposure to ethanol at 1,000 ppm or lower or to concentrations that could be encountered upon refueling is not likely to cause any significant neuromotor alterations in healthy males.

Micro RNA responses to chronic or acute exposures to low dose ionizing radiation

PubMed Central

Chaudhry, M. Ahmad; Omaruddin, Romaica A.; Kreger, Bridget; de Toledo, Sonia M.; Azzam, Edouard I.

2014-01-01

Human health risks of exposure to low dose ionizing radiation remain ambiguous and are the subject of intense debate. A wide variety of biological effects are induced after cellular exposure to ionizing radiation, but the underlying molecular mechanism(s) remain to be completely understood. We hypothesized that low dose c-radiation-induced effects are controlled by the modulation of micro RNA (miRNA) that participate in the control of gene expression at the posttranscriptional level and are involved in many cellular processes. We monitored the expression of several miRNA in human cells exposed to acute or chronic low doses of 10 cGy or a moderate dose of 400 cGy of 137Cs γ-rays. Dose, dose rate and time dependent differences in the relative expression of several miRNA were investigated. The expression patterns of many miRNA differed after exposure to either chronic or acute 10 cGy. The expression of miRNA let-7e, a negative regulator of RAS oncogene, and the c-MYC miRNA cluster were upregulated after 10 cGy chronic dose but were downregulated after 3 h of acute 10 cGy. The miR-21 was upregulated in chronic or acute low dose and moderate dose treated cells and its target genes hPDCD4, hPTEN, hSPRY2, and hTPM1 were found to be downregulated. These findings provide evidence that low dose and dose rate c-irradiation dictate the modulation of miRNA, which can result in a differential cellular response than occurs at high doses. This information will contribute to understanding the risks to human health after exposure to low dose radiation. PMID:22367372

Responses of Hyalella azteca to acute and chronic microplastic exposures.

PubMed

Au, Sarah Y; Bruce, Terri F; Bridges, William C; Klaine, Stephen J

2015-11-01

Limited information is available on the presence of microplastics in freshwater systems, and even less is known about the toxicological implications of the exposure of aquatic organisms to plastic particles. The present study was conducted to evaluate the effects of microplastic ingestion on the freshwater amphipod, Hyalella azteca. Hyalella azteca was exposed to fluorescent polyethylene microplastic particles and polypropylene microplastic fibers in individual 250-mL chambers to determine 10-d mortality. In acute bioassays, polypropylene microplastic fibers were significantly more toxic than polyethylene microplastic particles; 10-d lethal concentration 50% values for polyethylene microplastic particles and polypropylene microplastic fibers were 4.64 × 10(4) microplastics/mL and 71.43 microplastics/mL, respectively. A 42-d chronic bioassay using polyethylene microplastic particles was conducted to quantify effects on reproduction, growth, and egestion. Chronic exposure to polyethylene microplastic particles significantly decreased growth and reproduction at the low and intermediate exposure concentrations. During acute exposures to polyethylene microplastic particles, the egestion times did not significantly differ from the egestion of normal food materials in the control; egestion times for polypropylene microplastic fibers were significantly slower than the egestion of food materials in the control. Amphipods exposed to polypropylene microplastic fibers also had significantly less growth. The greater toxicity of microplastic fibers than microplastic particles corresponded with longer residence times for the fibers in the gut. The difference in residence time might have affected the ability to process food, resulting in an energetic effect reflected in sublethal endpoints. © 2015 SETAC.

Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, Gary L., E-mail: gary.l.thompson.3@gmail.com; Roth, Caleb C.; Kuipers, Marjorie A.

2016-01-29

Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known tomore » be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.« less

AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

EPA Science Inventory

The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

Exposure to Cooking Fumes and Acute Reversible Decrement in Lung Functional Capacity.

PubMed

Neghab, Masoud; Delikhoon, Mahdieh; Norouzian Baghani, Abbas; Hassanzadeh, Jafar

2017-10-01

Being exposed to cooking fumes, kitchen workers are occupationally at risk of multiple respiratory hazards. No conclusive evidence exists as to whether occupational exposure to these fumes is associated with acute and chronic pulmonary effects and symptoms of respiratory diseases. To quantify the exposure levels and evaluate possible chronic and acute pulmonary effects associated with exposure to cooking fumes. In this cross-sectional study, 60 kitchen workers exposed to cooking fumes and 60 unexposed employees were investigated. The prevalence of respiratory symptoms among these groups was determined through completion of a standard questionnaire. Pulmonary function parameters were also measured before and after participants' work shift. Moreover, air samples were collected and analyzed to quantify their aldehyde, particle, and volatile organic contents. The mean airborne concentrations of formaldehyde, acetaldehyde, and acrolein was 0.45 (SD 0.41), 0.13 (0.1), and 1.56 (0.41) mg/m 3 , respectively. The mean atmospheric concentrations of PM 1 , PM 2.5 , PM 7 , PM 10 , and total volatile organic compounds (TVOCs) was 3.31 (2.6), 12.21 (5.9), 44.16 (16.6), 57 (21.55) μg/m 3 , and 1.31 (1.11) mg/m 3 , respectively. All respiratory symptoms were significantly (p<0.05) more prevalent in exposed group. No significant difference was noted between the pre-shift mean of spirometry parameters of exposed and unexposed group. However, exposed workers showed cross-shift decrease in most spirometry parameters, significantly lower than the pre-shift values and those of the comparison group. Exposure to cooking fumes is associated with a significant increase in the prevalence of respiratory symptoms as well as acute reversible decrease in lung functional capacity.

Long-Term Follow-up of the Delayed Effects of Acute Radiation Exposure in Primates

DTIC Science & Technology

2016-10-01

MV, Katz BP, Smith CP, Jackson W 3rd, Cohen DM, et al. A nonhuman primate model of the hematopoietic acute radiation syndrome plus medical management...subsyndrome of the acute radiation syndrome : a rhesus macaque model. Health Phys 2012; 103:411–26. 32. Robbins ME, Bourland JD, Cline JM, Wheeler KT, Deadwyler...AD______________ AWARD NUMBER: W81XWH-15-1-0574 TITLE: Long-Term Follow-up of the Delayed Effects of Acute Radiation Exposure in Primates

Role of acute ethanol exposure and TLR4 in early events of sepsis in a mouse model

PubMed Central

Bhatty, Minny; Jan, Basit L; Tan, Wei; Pruett, Stephen B; Nanduri, Bindu

2011-01-01

Sepsis is a major cause of death worldwide. The associated risks and mortality are known to significantly increase on exposure to alcohol (chronic or acute). The underlying mechanisms of the association of acute ethanol ingestion and poor prognosis of sepsis are largely unknown. The study described here was designed to determine in detail the role of ethanol and TLR4 in the pathogenesis of the sepsis syndrome. The effects of acute ethanol exposure and TLR4 on bacterial clearance, spleen cell numbers, peritoneal macrophage numbers, and cytokine production were evaluated using wild type and TLR4 hypo-responsive mice treated with ethanol and then challenged with a non pathogenic strain of Escherichia. coli (E. coli). Ethanol treated mice exhibited a decreased clearance of bacteria and produced lesser amounts of most pro-inflammatory cytokines in both strains of mice at two hours after challenge. Neither ethanol treatment nor a hypo-responsive TLR4 had significant effects on the cell numbers in the peritoneal cavity and spleen 2 hours post infection. The suppressive effect of acute ethanol exposure on cytokine and chemokine production was more pronounced in the wild type mice, but the untreated hyporesponsive mice produced less of most cytokines than untreated wild type mice. The major conclusion of this study is that acute ethanol exposure suppresses pro-inflammatory cytokine production and that a hypo-responsive TLR4 (in C3H/HeJ mice) decreases pro-inflammatory cytokine levels but the cytokines and other mediators induced through other receptors are sufficient to ultimately clear the infection but not enough to induce lethal septic shock. In addition, results reported here demonstrate previously unknown effects of acute ethanol exposure on LIF (leukemia inhibitory factor) and eotaxin and provide the first evidence that IL-9 is induced through TLR4 in vivo. PMID:21872420

Experience with 161 cases of anterior exposure of the thoracic and lumbar spine in an acute care surgery model: impact of exposure level and underlying pathology on morbidity.

PubMed

Seoudi, Hani; Laporta, Matthew; Griffen, Margaret; Rizzo, Anne; Pullarkat, Ranjit

2013-08-15

Retrospective chart review. To evaluate the outcomes of anterior exposure of the thoracic and lumbar spine by an acute care surgery service. Spine surgeons typically require an "approach surgeon" to provide anterior exposure of the thoracic and lumbar spine. We hypothesized that a dedicated acute care surgery service can perform those operations with acceptable morbidity and mortality. A retrospective review of 161 trauma and nontrauma patients was performed. All cases were performed at a level I trauma center with a dedicated acute care surgery service. In-hospital morbidity and mortality were evaluated. A brief description of the operative techniques used by our group is also provided. Of the 161 patients, 59 (37%) were trauma patients. Ninety-three patients (58%) had anterolateral retroperitoneal exposure of the thoracic and lumbar spine. Sixty-eight patients (42%) had anterior retroperitoneal midline exposure of the lumbar and lumbosacral spine. Total morbidity was 9.3% (7.4% for trauma patients and 1.8% for non trauma patients). Morbidity was highest in patients who had anterolateral exposure of the thoracic and lumbar spine (6.8%). Morbidity in patients who had midline exposure of L4 to S1 was 0%. Total mortality was 1.2% (3.3% for trauma patients and 0% for nontrauma patients). The acute care surgery service gained 3141 physician work relative value units (RVU) by performing those operations. Anterior exposure of the thoracic and lumbar spine both for trauma and nontrauma related indications can be performed with acceptable morbidity and mortality by a dedicated acute care surgery service. Morbidity and mortality were higher in trauma patients and in those who underwent thoracolumbar procedures. Patients who had midline exposure of L4 to S1 for degenerative disc disease had the lowest morbidity. 4.

A registry for exposure and population health in the Altai region affected by fallout from the Semipalatinsk nuclear test site.

PubMed

Shoikhet, Y N; Kiselev, V I; Zaitsev, E V; Kolyado, I B; Konovalov, B Y; Bauer, S; Grosche, B; Burkart, W

1999-09-01

A registry of the rural population in the Altai region exposed to fallout from nuclear tests at the Semipalatinsk test site (STS) was established more than four decades after the first Soviet nuclear explosion on August 29, 1949. Information about individuals living in an exposed and a control area was collected using all available local sources, such as kolkhoz documentation, school registries, medical treatment records and interviews with residents. As a result, a database comprising an exposed group of 39 179 individuals from 53 Altai region villages, 6769 external and 3303 internal controls was compiled. For several settlements, effective dose estimates reached the level of 1.5 Sv, while the average effective dose estimate in the exposed group was 340 mSv. Dosimetric data, vital status information and health records gathered at rayon and village medical facilities are held in the registry. Cause-of-death information for deceased residents is obtained from death registration forms archived at the Altai region vital statistics office. At present, a follow-up of approximately 40% of the population exposed in 1949 has been done. More will be added by searching for migrants to the larger towns of the Altai region, i.e. Barnaul, Rubtsovsk and Biisk. In order to assess the influence of radiation exposure, analytical studies with a case-control design for stomach and lung cancer are currently being prepared. The number of known cases is sufficient to detect an odds ratio of 1.5 at the 95% confidence level. Epidemiological studies in populations affected by fallout from STS may be equally important to the atomic bomb survivors' study for the direct quantification of radiation effects. The range of exposure rates experienced will extend the acute high-dose-rate findings from Hiroshima/Nagasaki towards acute and protracted lower exposures, which are more relevant for radiation protection issues.

Glucocorticoid exposure alters the pathogenesis of Theiler’s murine encephalomyelitis virus during acute infection

PubMed Central

Young, Erin E.; Prentice, Thomas W.; Satterlee, Danielle; McCullough, Heath; Sieve, Amy N.; Johnson, Robin R.; Welsh, Thomas H.; Welsh, C. Jane R.; Meagher, Mary W.

2008-01-01

Previous research has shown that chronic restraint stress exacerbates Theiler’s virus infection, a murine model for CNS inflammation and multiple sclerosis. The current set of experiments was designed to evaluate the potential role of glucocorticoids in the deleterious effects of restraint stress on acute CNS inflammatory disease. Exposure to chronic restraint stress resulted in elevated levels of corticosterone as well as increased clinical scores and weight loss (Experiment 1). In addition, corticosterone administration alone exacerbated behavioral signs of TMEV-induced sickness (i.e. decreased body weight, increased symptoms of encephalitis, and increased mortality) and reduced inflammation in the CNS (Experiment 2). Infected subjects receiving exogenous corticosterone showed exacerbation of acute phase measures of sickness and severe mortality as well as decreased viral clearance from CNS (Experiment 3). These findings indicate that corticosterone exposure alone is sufficient to exacerbate acute CNS inflammatory disease. PMID:18538803

Acute symptoms following exposure to grain dust in farming.

PubMed Central

Manfreda, J; Holford-Strevens, V; Cheang, M; Warren, C P

1986-01-01

History of acute symptoms (cough, wheezing, shortness of breath, fever, stuffy nose, and skin itching/rash) following exposure to grain dust was obtained from 661 male and 535 female current and former farmers. These symptoms were relatively common: 60% of male and 25% of female farmers reported at least one such symptom on exposure to grain dust. Association of cough, wheezing, shortness of breath, and stuffy nose with skin reactivity and capacity to form IgE is consistent with an allergic nature of these symptoms. Barley and oats dust were perceived as dust most often producing symptoms. On the other hand, grain fever showed a different pattern, i.e., it was not associated with either skin reactivity or total IgE. Smoking might modify the susceptibility to react to grain dust with symptoms. Only those who reported wheezing on exposure to grain dust may have an increased risk to develop chronic airflow obstruction. PMID:3709486

Psychological symptoms and intermittent hypertension following acute microwave exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forman, S.A.; Holmes, C.K.; McManamon, T.V.

1982-11-01

Two men who were accidently, acutely irradiated with X-band microwave radiation have been followed up clinically for 12 months. Both men developed similar psychological symptoms, which included emotional lability, irritability, headaches, and insomnia. Several months after the incidents, hypertension was diagnosed in both patients. No organic basis for the psychological problems could be found nor could any secondary cause for the hypertension. A similar syndrome following microwave exposure has been described by the East Europeans. The two cases we report, with comparable subjective symptoms and hypertension following a common exposure, provide further strong, circumstantial evidence of cause and effect. Amore » greater knowledge of the mechanisms involved in bioeffects which may be induced by radiofrequency and microwave radiation is definitely needed.« less

Comprehensive proteome analysis of nasal lavage samples after controlled exposure to welding nanoparticles shows an induced acute phase and a nuclear receptor, LXR/RXR, activation that influence the status of the extracellular matrix.

PubMed

Ali, Neserin; Ljunggren, Stefan; Karlsson, Helen M; Wierzbicka, Aneta; Pagels, Joakim; Isaxon, Christina; Gudmundsson, Anders; Rissler, Jenny; Nielsen, Jörn; Lindh, Christian H; Kåredal, Monica

2018-01-01

Epidemiological studies have shown that many welders experience respiratory symptoms. During the welding process a large number of airborne nanosized particles are generated, which might be inhaled and deposited in the respiratory tract. Knowledge of the underlying mechanisms behind observed symptoms is still partly lacking, although inflammation is suggested to play a central role. The aim of this study was to investigate the effects of welding fume particle exposure on the proteome expression level in welders suffering from respiratory symptoms, and changes in protein mediators in nasal lavage samples were analyzed. Such mediators will be helpful to clarify the pathomechanisms behind welding fume particle-induced effects. In an exposure chamber, 11 welders with work-related symptoms in the lower airways during the last month were exposed to mild-steel welding fume particles (1 mg/m 3 ) and to filtered air, respectively, in a double-blind manner. Nasal lavage samples were collected before, immediately after, and the day after exposure. The proteins in the nasal lavage were analyzed with two different mass spectrometry approaches, label-free discovery shotgun LC-MS/MS and a targeted selected reaction monitoring LC-MS/MS analyzing 130 proteins and four in vivo peptide degradation products. The analysis revealed 30 significantly changed proteins that were associated with two main pathways; activation of acute phase response signaling and activation of LXR/RXR, which is a nuclear receptor family involved in lipid signaling. Connective tissue proteins and proteins controlling the degradation of such tissues, including two different matrix metalloprotease proteins, MMP8 and MMP9, were among the significantly changed enzymes and were identified as important key players in the pathways. Exposure to mild-steel welding fume particles causes measurable changes on the proteome level in nasal lavage matrix in exposed welders, although no clinical symptoms were manifested. The

Sources and magnitude of occupational and public exposures from nuclear medicine procedures

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This Report addresses the sources of exposures incurred in the practice of nuclear medicine and provides the necessary data to evaluate the magnitude of exposures to those directly associated with that practice and to those who provide nursing care to the patients containing radiopharmaceuticals. Exposure to members of the public are also addressed. The primary emphasis of this Report is on these individuals and not on the patient, since the patient receives the direct benefit from the nuclear medicine procedure. It is recognized that the patient also receives the bulk of any potential radiation decrement.

Short term inhalation exposure to turpentine: toxicokinetics and acute effects in men.

PubMed Central

Filipsson, A F

1996-01-01

OBJECTIVES: This study describes the toxicokinetics, pulmonary function, and subjective ratings of discomfort in volunteers experimentally exposed to turpentine vapour (a mixture of monoterpenes). The results were compared with similar exposure to single monoterpenes to look in the toxicokinetics and acute effects for signs of interactions between the monoterpenes. METHODS: Eight male volunteers were exposed to 450 mg/m3 turpentine by inhalation (2 h, 50 W) in an exposure chamber. RESULTS: The mean relative uptakes of alpha-pinene, beta-pinene, and 3-carene were 62%, 66%, and 68% respectively, of the amount supplied. Between 2% and 5% of the net uptake was excreted unchanged in the expired air after the end of exposure. The mean blood clearance 21 hours after exposure (CL21h) of alpha-pinene, beta-pinene and 3-carene, were 0.8, 0.5, and 0.4 l.kg-1.h-1, respectively. The mean half lives (t1/2) of the last phase of alpha-pinene, beta-pinene, and 3-carene averaged 32, 25, and 42 hours, respectively. The t1/2s agreed with previously calculated half lives from single exposures. The total blood clearance CL21h of 3-carene found in this turpentine study was lower, and CL4h of 3-carene was significantly lower than the values obtained from similar exposure to pure 3-carene. The subjects attending both exposure to turpentine and to pure alpha-pinene at 450 mg/m3 had lower CL4h during the exposure to turpentine, when they experienced more discomfort of the throat or the airways (F = 5.7, P = 0.048) than during exposure to control concentrations. After experimental exposure to turpentine an increase in airway resistance was found that differed significantly from results of exposure to 3-carene at 10 mg/m3 (P = 0.021) or 450 mg/m3 (P = 0.047). CONCLUSIONS: Toxicokinetics and acute effects show small, if any, interactions between alpha-pinene, beta-pinene, and 3-carene. The subjects experienced discomfort in the throat and airways during exposure to turpentine and airway

Mice and the A-Bomb: Irradiation Systems for Realistic Exposure Scenarios.

PubMed

Garty, Guy; Xu, Yanping; Elliston, Carl; Marino, Stephen A; Randers-Pehrson, Gerhard; Brenner, David J

2017-04-01

Validation of biodosimetry assays is normally performed with acute exposures to uniform external photon fields. Realistically, exposure to a radiological dispersal device or reactor leak will include exposure to low dose rates and likely exposure to ingested radionuclides. An improvised nuclear device will likely include a significant neutron component in addition to a mixture of high- and low-dose-rate photons and ingested radionuclides. We present here several novel irradiation systems developed at the Center for High Throughput Minimally Invasive Radiation Biodosimetry to provide more realistic exposures for testing of novel biodosimetric assays. These irradiators provide a wide range of dose rates (from Gy/s to Gy/week) as well as mixed neutron/photon fields mimicking an improvised nuclear device.

Mice and the A-Bomb: Irradiation Systems for Realistic Exposure Scenarios

PubMed Central

Garty, Guy; Xu, Yanping; Elliston, Carl; Marino, Stephen A.; Randers-Pehrson, Gerhard; Brenner, David J.

2017-01-01

Validation of biodosimetry assays is normally performed with acute exposures to uniform external photon fields. Realistically, exposure to a radiological dispersal device or reactor leak will include exposure to low dose rates and likely exposure to ingested radionuclides. An improvised nuclear device will likely include a significant neutron component in addition to a mixture of high- and low-dose-rate photons and ingested radionuclides. We present here several novel irradiation systems developed at the Center for High Throughput Minimally Invasive Radiation Biodosimetry to provide more realistic exposures for testing of novel biodosimetric assays. These irradiators provide a wide range of dose rates (from Gy/s to Gy/week) as well as mixed neutron/photon fields mimicking an improvised nuclear device. PMID:28211757

Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008.

PubMed

Longo, Bernadette M; Yang, Wei; Green, Joshua B; Crosby, Frederick L; Crosby, Vickie L

2010-01-01

In 2008, the Kilauea Volcano on the island of Hawai'i increased eruption activity and emissions of sulfurous volcanic air pollution called vog. The purpose of this study was to promptly assess for a relative increase in cases of medically diagnosed acute illnesses in an exposed Hawaiian community. Using a within-clinic retrospective cohort design, comparisons were made for visits of acute illnesses during the 14 wk prior to the increased volcanic emissions (low exposure) to 14 wk of high vog exposure when ambient sulfur dioxide was threefold higher and averaged 75 parts per billion volume per day. Logistic regression analysis estimated effect measures between the low- and high-exposure cohorts for age, gender, race, and smoking status. There were statistically significant positive associations between high vog exposure and visits for medically diagnosed cough, headache, acute pharyngitis, and acute airway problems. More than a sixfold increase in odds was estimated for visits with acute airway problems, primarily experienced by young Pacific Islanders. These findings suggest that the elevated volcanic emissions in 2008 were associated with increased morbidity of acute illnesses in age and racial subgroups of the general Hawaiian population. Continued investigation is crucial to fully assess the health impact of this natural source of sulfurous air pollution. Culturally appropriate primary- and secondary-level health prevention initiatives are recommended for populations in Hawai'i and volcanically active areas worldwide.

Effects of acute exposure to WIFI signals (2.45GHz) on heart variability and blood pressure in Albinos rabbit.

PubMed

Saili, Linda; Hanini, Amel; Smirani, Chiraz; Azzouz, Ines; Azzouz, Amina; Sakly, Mohsen; Abdelmelek, Hafedh; Bouslama, Zihad

2015-09-01

Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system. Copyright © 2015 Elsevier B.V. All rights reserved.

Openness to experience and adapting to change: Cardiovascular stress habituation to change in acute stress exposure.

PubMed

Ó Súilleabháin, Páraic S; Howard, Siobhán; Hughes, Brian M

2018-05-01

Underlying psychophysiological mechanisms of effect linking openness to experience to health outcomes, and particularly cardiovascular well-being, are unknown. This study examined the role of openness in the context of cardiovascular responsivity to acute psychological stress. Continuous cardiovascular response data were collected for 74 healthy young female adults across an experimental protocol, including differing counterbalanced acute stressors. Openness was measured via self-report questionnaire. Analysis of covariance revealed openness was associated with systolic blood pressure (SBP; p = .016), and diastolic blood pressure (DBP; p = .036) responsivity across the protocol. Openness was also associated with heart rate (HR) responding to the initial stress exposure (p = .044). Examination of cardiovascular adaptation revealed that higher openness was associated with significant SBP (p = .001), DBP (p = .009), and HR (p = .002) habituation in response to the second differing acute stress exposure. Taken together, the findings suggest persons higher in openness are characterized by an adaptive cardiovascular stress response profile within the context of changing acute stress exposures. This study is also the first to demonstrate individual differences in cardiovascular adaptation across a protocol consisting of differing stress exposures. More broadly, this research also suggests that future research may benefit from conceptualizing an adaptive fitness of openness within the context of change. In summary, the present study provides evidence that higher openness stimulates short-term stress responsivity, while ensuring cardiovascular habituation to change in stress across time. © 2017 Society for Psychophysiological Research.

Acute and Chronic Ethanol Exposure Differentially Regulate CB1 Receptor Function at Glutamatergic Synapses in the Rat Basolateral Amygdala

PubMed Central

Robinson, Stacey L.; Alexander, Nancy J.; Bluett, Rebecca J.; Patel, Sachin; McCool, Brian A.

2016-01-01

The endogenous cannabinoid (eCB) system has been suggested to play a key role in ethanol preference and intake, the acute effects of ethanol, and in the development of withdrawal symptoms following ethanol dependence. Ethanol-dependent alterations in glutamatergic signaling within the lateral/basolateral nucleus of the amygdala (BLA) are critical for the development and expression of withdrawal-induced anxiety. Notably, the eCB system significantly regulates both glutamatergic and GABAergic synaptic activity within the BLA. Chronic ethanol exposure significantly alters eCB system expression within regions critical to the expression of emotionality and anxiety-related behavior, including the BLA. Here, we investigated specific interactions between the BLA eCB system and its functional regulation of synaptic activity during acute and chronic ethanol exposure. In tissue from ethanol naïve-rats, a prolonged acute ethanol exposure caused a dose dependent inhibition of glutamatergic synaptic activity via a presynaptic mechanism that was occluded by CB1 antagonist/inverse agonists SR141716a and AM251. Importantly, this acute ethanol inhibition was attenuated following 10 day chronic intermittent ethanol vapor exposure (CIE). CIE exposure also significantly down-regulated CB1-mediated presynaptic inhibition at glutamatergic afferent terminals but spared CB1-inhibition of GABAergic synapses arising from local inhibitory-interneurons. CIE also significantly elevated BLA N-arachidonoylethanolamine (AEA or anandamide) levels and decreased CB1 receptor protein levels. Collectively, these data suggest a dynamic regulation of the BLA eCB system by acute and chronic ethanol. PMID:26707595

Acute exposure to wood smoke from incomplete combustion--indications of cytotoxicity.

PubMed

Muala, Ala; Rankin, Gregory; Sehlstedt, Maria; Unosson, Jon; Bosson, Jenny A; Behndig, Annelie; Pourazar, Jamshid; Nyström, Robin; Pettersson, Esbjörn; Bergvall, Christoffer; Westerholm, Roger; Jalava, Pasi I; Happo, Mikko S; Uski, Oskari; Hirvonen, Maija-Riitta; Kelly, Frank J; Mudway, Ian S; Blomberg, Anders; Boman, Christoffer; Sandström, Thomas

2015-10-29

Smoke from combustion of biomass fuels is a major risk factor for respiratory disease, but the underlying mechanisms are poorly understood. The aim of this study was to determine whether exposure to wood smoke from incomplete combustion would elicit airway inflammation in humans. Fourteen healthy subjects underwent controlled exposures on two separate occasions to filtered air and wood smoke from incomplete combustion with PM1 concentration at 314 μg/m(3) for 3 h in a chamber. Bronchoscopy with bronchial wash (BW), bronchoalveolar lavage (BAL) and endobronchial mucosal biopsies was performed after 24 h. Differential cell counts and soluble components were analyzed, with biopsies stained for inflammatory markers using immunohistochemistry. In parallel experiments, the toxicity of the particulate matter (PM) generated during the chamber exposures was investigated in vitro using the RAW264.7 macrophage cell line. Significant reductions in macrophage, neutrophil and lymphocyte numbers were observed in BW (p < 0.01, <0.05, <0.05, respectively) following the wood smoke exposure, with a reduction in lymphocytes numbers in BAL fluid (<0.01. This unexpected cellular response was accompanied by decreased levels of sICAM-1, MPO and MMP-9 (p < 0.05, <0.05 and <0.01). In contrast, significant increases in submucosal and epithelial CD3+ cells, epithelial CD8+ cells and submucosal mast cells (p < 0.01, <0.05, <0.05 and <0.05, respectively), were observed after wood smoke exposure. The in vitro data demonstrated that wood smoke particles generated under these incomplete combustion conditions induced cell death and DNA damage, with only minor inflammatory responses. Short-term exposure to sooty PAH rich wood smoke did not induce an acute neutrophilic inflammation, a classic hallmark of air pollution exposure in humans. While minor proinflammatory lymphocytic and mast cells effects were observed in the bronchial biopsies, significant reductions in BW and BAL cells and

Single-centre experience of radiation exposure in acute surgical patients: assessment of therapeutic impact and future recommendations.

PubMed

Fitzmaurice, Gerard J; Brown, Robin; Cranley, Brian; Conlon, Enda F; Todd, R Alan J; O'Donnell, Mark E

2010-09-01

Radiological investigations have become a key adjunct in patient management and consequently radiation exposure to patients is increasing. The study objectives were to examine the use of radiological investigations in the management of acute surgical patients and to assess whether a guideline-based radiation exposure risk/benefit analysis can aid in the choice of radiological investigation used. A prospective observational study was completed over a 12-week period from April to July 2008 for all acute surgical admissions. Data recorded included demographics, clinical presentation, differential diagnosis, investigations, surgical interventions, and final clinical outcome. The use of radiological investigative modalities as an adjunct to clinical assessment was then evaluated against The Royal College of Radiologists (RCR) guidelines. A total of 380 acute surgical admissions (M = 174, F = 185, children = 21) were assessed during the study period. Seven hundred thirty-four radiological investigations were performed with a mean of 1.93 investigations per patient. Based on the RCR guidelines, 680 (92.6%) radiological investigations were warranted and included 142 CT scans (19.3%), 129 chest X-rays (17.6%), and 85 abdominal X-rays (11.6%). Clinically, radiological imaging complemented surgical management in 326 patients (85.8%) and the management plan remained unchanged for the remaining 54 patients (14.2%). This accounted for an average radiation dose of 4.18 millisievert (mSv) per patient or 626 days of background radiation exposure. CT imaging was responsible for the majority of the radiation exposure, with a total of 1310 mSv (82.6%) of the total radiation exposure being attributed to CT imaging in 20.8% of acute admissions. Subgroup analysis demonstrated that 92.8% of the CT scans performed were appropriate. Radiation exposure was generally low for the majority of acute surgical admissions. However, it is recommended that CT imaging requests be evaluated carefully

N-Acetyl Cysteine does not prevent liver toxicity from chronic low dose plus sub-acute high dose paracetamol exposure in young or old mice

PubMed Central

Kane, Alice-Elizabeth; Huizer-Pajkos, Aniko; Mach, John; McKenzie, Catriona; Mitchell, Sarah-Jayne; de Cabo, Rafael; Jones, Brett; Cogger, Victoria; Le Couteur, David G; Hilmer, Sarah-Nicole

2016-01-01

Paracetamol is an analgesic commonly used by people of all ages, which is well documented to cause severe hepatotoxicity with acute over-exposures. The risk of hepatotoxicity from non-acute paracetamol exposures is less extensively studied, and this is the exposure most common in older adults. Evidence on the effectiveness of N-acetyl cysteine (NAC) for non-acute paracetamol exposures, in any age group, is lacking. This study aimed to examine the effect of long-term exposure to therapeutic doses of paracetamol and sub-acute paracetamol over-exposure, in young and old mice, and to investigate whether NAC was effective at preventing paracetamol hepatotoxicity induced by these exposures. Young and old male C57BL/6 mice were fed a paracetamol-containing (1.33g/kg food) or control diet for 6 weeks. Mice were then dosed orally 8 times over 3 days with additional paracetamol (250mg/kg) or saline, followed by either one or two doses of oral NAC (1200mg/kg) or saline. Chronic low-dose paracetamol exposure did not cause hepatotoxicity in young or old mice, measured by serum alanine aminotransferase (ALT) elevation, and confirmed by histology and a DNA fragmentation assay. Sub-acute paracetamol exposure caused significant hepatotoxicity in young and old mice, measured by biochemistry (ALT) and histology. Neither a single nor double dose of NAC protected against this toxicity from sub-acute paracetamol in young or old mice. This finding has important clinical implications for treating toxicity due to different paracetamol exposure types in patients of all ages, and implies a need to develop new treatments for sub-acute paracetamol toxicity. PMID:26821200

Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures

USGS Publications Warehouse

Wang, Ning; Consbrock, Rebecca A.; Ingersoll, Christopher G.; Hardesty, Douglas K.; Brumbaugh, William G.; Hammer, Edward J.; Bauer, Candice R.; Mount, David R.

2016-01-01

The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1mg K/L to 3mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

Responses of the soft coral Xenia elongata following acute exposure to a chemical dispersant.

PubMed

Studivan, Michael S; Hatch, Walter I; Mitchelmore, Carys L

2015-01-01

Limited toxicology data are available regarding oil dispersant exposure to coral species. Corexit® EC9500A (Corexit) is a commonly applied dispersant most well known for its use after the Deepwater Horizon spill in April, 2010. There is limited evidence that Corexit can cause a bleaching response in corals. The aims of the study were: (1) to determine the extent of bleaching after acute 24 h and 72 h exposures of sublethal concentrations (0-50 ppm) of Corexit to the pulsing soft coral Xenia elongata and (2) to investigate a percent symbiont loss calculation using zooxanthellae density. The percent symbiont loss calculation was compared to a traditional metric of normalizing zooxanthellae density to soluble protein content. Percent symbiont loss was an effective measure of coral stress in acute Corexit exposures, while protein normalized zooxanthellae density was more variable. The bleaching data suggest a positive relationship between dispersant concentration and percent symbiont loss, culminating in excessive tissue necrosis and coral mortality within 72 h in high concentration exposures (p < 0.001). Percent beaching ranged from 25% in 5 ppm exposures to 100% in 50 ppm exposures. Corexit also caused a significant decrease in pulse activity (p < 0.0001) and relative oxygen saturation (p < 0.001), possibly indicating a reduction in photosynthetic efficiency. This study and other similar research indicate that dispersant exposure is highly damaging to marine organisms, including ecologically important coral species.

Tadpole swimming performance and activity affected by acute exposure to sublethal levels of carbaryl

USGS Publications Warehouse

Bridges, C.M.

1997-01-01

General activity and swimming performance (i.e., sprint speed and distance) of plains leopard frog tadpoles (Rana blairi) were examined after acute exposure to three sublethal concentrations of carbaryl (3.5, 5.0, and 7.2 mg/L). Both swimming performance and spontaneous swimming activity are important for carrying out life history functions (e.g., growth and development) and for escaping from predators. Measured tadpole activity diminished by nearly 90% at 3.5 mg/L carbaryl and completely ceased at 7.2 mg/L. Sprint speed and sprint distance also decreased significantly following exposure. Carbaryl affected both swimming performance and activity after just 24 h, suggesting that 24 h may be an adequate length of exposure to determine behavioral effects on tadpoles. Slight recovery of activity levels was noted at 24 and 48 h post-exposure; no recovery of swimming performance was observed. Reduction in activity and swimming performance may result in increased predation rates and, because activity is closely associated with feeding, may result in slowed growth leading to a failure to emerge before pond drying or an indirect reduction in adult fitness. Acute exposure to sublethal toxicants such as carbaryl may not only affect immediate survival of tadpoles but also impact critical life history functions and generate changes at the local population level.

Acute trimethyltin exposure induces oxidative stress response and neuronal apoptosis in Sebastiscus marmoratus.

PubMed

Wang, Xinli; Cai, Jiali; Zhang, Jiliang; Wang, Chonggang; Yu, Ang; Chen, Yixin; Zuo, Zhenghong

2008-10-20

Trimethyltin (TMT) is a well-documented neurotoxicant that affects the function of central nervous system (CNS). In this study, we studied the neurotoxicity of TMT on the brain of marine fish Sebastiscus marmoratus. Our results showed that TMT acute exposure induced brain cell apoptosis in the telencephalon, optic tectum and cerebellum. In addition, we observed increased production of reactive oxygen species (ROS), nitric oxide (NO) and one asparate-specific cysteinyl protease named caspase-3 which are often associated with the processes of cell apoptosis, in the brain of S. marmoratus after acute treatment of TMT. Our results indicated that TMT induces neurotoxicity and oxidative stress in marine fish S. marmoratus. Our results suggested that TMT exposure in the environment may affect fish behaviors including schooling, sensory and motorial learnings, based on the observation of cell apoptosis in the cerebral regions.

Effects of acute ozone exposure on the electrophysiological properties of guinea pig trachea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Croxton, T.L.; Takahashi, Masahiko; Kokia, Ira

1994-12-31

Acute ozone (O{sub 3}) exposures produce an increase in the apparent permeability of the tracheal epithelium, but the mechanism of this response is poorly understood. Comparison of previous studies suggests that qualitative differences may exist between measurements made in vivo or in vitro. To test this possibility we used both in vitro and in vivo electrophysiological techniques to investigate the effects of O{sub 3} exposure on guinea pig tracheal epithelium. Male Hartley guinea pigs were exposed to either 1 or 2 ppm O{sub 3} or to filtered air for 3 h and were studied 0, 6, or 24 h aftermore » exposure. Air-exposed animals had in vitro mean tracheal potential (V{sub T}) -32.0 {+-} 1.5 mV, conductance (G{sub T}{sup L}) 2.18 {+-} 0.22 mS/cm, short-circuit current (I{sub SC}{sup L}) 62.6 {+-} 3.7 {mu}A/cm, and diameter (D) 2.44 {+-} 0.10 mm. In vitro properties after 1 ppm O{sub 3} exposure did not differ at any time point from control. Two parts per million O{sub 3} increased I{sub SC}{sup L}, but only at 6 h postexposure. The effect of O{sub 3} on I{sub SC}{sup L} was abolished by amiloride. There were no significant changes in V{sub T}, G{sub T}{sup L}, or D. In vivo tracheal potential under pentobarbital anesthesia was -19.7 {+-} 1.7 mV. At 6 h postexposure to 2 ppm O{sub 3}, but not at 0 or 24 h, in vivo V{sub I} was increased. Thus, acute exposure of guinea pigs to a high concentration of O{sub 3} caused a delayed increase in Na{sup +} absorption by the trachea with no change in conductance. This indicates that paracellular permeability of guinea pig tracheal epithelium was not substantially increased by acute O{sub 3} and suggests that enhanced macromolecular uptake in this species probably occurs transcellularly. 24 refs., 1 fig., 2 tabs.« less

Stress sensitizes the brain: increased processing of unpleasant pictures after exposure to acute stress.

PubMed

Weymar, Mathias; Schwabe, Lars; Löw, Andreas; Hamm, Alfons O

2012-07-01

A key component of acute stress is a surge in vigilance that enables a prioritized processing of highly salient information to promote the organism's survival. In this study, we investigated the neural effects of acute stress on emotional picture processing. ERPs were measured during a deep encoding task, in which 40 male participants categorized 50 unpleasant and 50 neutral pictures according to arousal and valence. Before picture encoding, participants were subjected either to the Socially Evaluated Cold Pressor Test (SECPT) or to a warm water control procedure. The exposure to the SECPT resulted in increased subjective and autonomic (heart rate and blood pressure) stress responses relative to the control condition. Viewing of unpleasant relative to neutral pictures evoked enhanced late positive potentials (LPPs) over centro-parietal scalp sites around 400 msec after picture onset. Prior exposure to acute stress selectively increased the LPPs for unpleasant pictures. Moreover, the LPP magnitude for unpleasant pictures following the SECPT was positively associated with incidental free recall performance 24 hr later. The present results suggest that acute stress sensitizes the brain for increased processing of cues in the environment, particularly priming the processing of unpleasant cues. This increased processing is related to later long-term memory performance.

Dexamethasone exposure and asparaginase antibodies affect relapse risk in acute lymphoblastic leukemia

PubMed Central

Kawedia, Jitesh D.; Liu, Chengcheng; Pei, Deqing; Cheng, Cheng; Fernandez, Christian A.; Howard, Scott C.; Campana, Dario; Panetta, John C.; Bowman, W. Paul; Evans, William E.; Pui, Ching-Hon

2012-01-01

We have previously hypothesized that higher systemic exposure to asparaginase may cause increased exposure to dexamethasone, both critical chemotherapeutic agents for acute lymphoblastic leukemia. Whether interpatient pharmaco-kinetic differences in dexamethasone contribute to relapse risk has never been studied. The impact of plasma clearance of dexamethasone and anti–asparaginase antibody levels on risk of relapse was assessed in 410 children who were treated on a front-line clinical trial for acute lymphoblastic leukemia and were evaluable for all pharmacologic measures, using multivariate analyses, adjusting for standard clinical and biologic prognostic factors. Dexamethasone clearance (mean ± SD) was higher (P = 3 × 10−8) in patients whose sera was positive (17.7 ± 18.6 L/h per m2) versus nega-tive (10.6 ± 5.99 L/h per m2) for anti–asparaginase antibodies. In multivariate analyses, higher dexamethasone clearance was associated with a higher risk of any relapse (P = .01) and of central nervous system relapse (P = .014). Central nervous system relapse was also more common in patients with anti–asparaginase antibodies (P = .019). In conclusion, systemic clearance of dexamethasone is higher in patients with anti–asparaginase antibodies. Lower exposure to both drugs was associated with an increased risk of relapse. PMID:22117041

Oxygen Exposure Resulting in Arterial Oxygen Tensions Above the Protocol Goal Was Associated With Worse Clinical Outcomes in Acute Respiratory Distress Syndrome.

PubMed

Aggarwal, Neil R; Brower, Roy G; Hager, David N; Thompson, B Taylor; Netzer, Giora; Shanholtz, Carl; Lagakos, Adrian; Checkley, William

2018-04-01

High fractions of inspired oxygen may augment lung damage to exacerbate lung injury in patients with acute respiratory distress syndrome. Participants enrolled in Acute Respiratory Distress Syndrome Network trials had a goal partial pressure of oxygen in arterial blood range of 55-80 mm Hg, yet the effect of oxygen exposure above this arterial oxygen tension range on clinical outcomes is unknown. We sought to determine if oxygen exposure that resulted in a partial pressure of oxygen in arterial blood above goal (> 80 mm Hg) was associated with worse outcomes in patients with acute respiratory distress syndrome. Longitudinal analysis of data collected in these trials. Ten clinical trials conducted at Acute Respiratory Distress Syndrome Network hospitals between 1996 and 2013. Critically ill patients with acute respiratory distress syndrome. None. We defined above goal oxygen exposure as the difference between the fraction of inspired oxygen and 0.5 whenever the fraction of inspired oxygen was above 0.5 and when the partial pressure of oxygen in arterial blood was above 80 mm Hg. We then summed above goal oxygen exposures in the first five days to calculate a cumulative above goal oxygen exposure. We determined the effect of a cumulative 5-day above goal oxygen exposure on mortality prior to discharge home at 90 days. Among 2,994 participants (mean age, 51.3 yr; 54% male) with a study-entry partial pressure of oxygen in arterial blood/fraction of inspired oxygen that met acute respiratory distress syndrome criteria, average cumulative above goal oxygen exposure was 0.24 fraction of inspired oxygen-days (interquartile range, 0-0.38). Participants with above goal oxygen exposure were more likely to die (adjusted interquartile range odds ratio, 1.20; 95% CI, 1.11-1.31) and have lower ventilator-free days (adjusted interquartile range mean difference of -0.83; 95% CI, -1.18 to -0.48) and lower hospital-free days (adjusted interquartile range mean difference of -1.38; 95

Acute nonlymphocytic leukemia and residential exposure to power frequency magnetic fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Severson, R.K.

1986-01-01

A population-based case-control study of adult acute nonlymphocytic leukemia (ANLL) and residential exposure to power frequency magnetic fields was conducted in King, Pierce and Snohomish Counties in Washington state. Of 164 cases who were diagnosed from January 1, 1981 through December 31, 1984, 114 were interviewed. Controls were selected from the study area on the basis of random digit dialing and frequency matched to the cases by age and sex. Analyses were undertaken to evaluate whether exposure to high levels of power frequency magnetic fields in the residence were associated with an increased risk of ANLL. Neither the directly measuredmore » magnetic fields nor the surrogate values based on the wiring configurations were associated with ANLL. Additional analyses suggested that persons with prior allergies were at decreased risk of acute myelocytic leukemia (AML). Also, persons with prior autoimmune diseases were at increased risk of AML. The increase in AML risk in rheumatoid arthritics was of borderline statistical significance. Finally, cigarette smoking was associated with an increased risk of AML. The risk of AML increased significantly with the number of years of cigarette smoking.« less

Acute pulmonary effects of nitrogen dioxide exposure during exercise in competitive athletes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, S.U.; Koenig, J.Q.; Pierson, W.E.

The acute pulmonary responses of athletes after short-term exposure to ambient concentrations of NO{sub 2} during heavy exercise have been examined. Intercollegiate male athletes were screened for history of cardiac disease, respiratory disease, allergic conditions and extensive exposure to pollutants. After completion of serum IgE level determination, exercise tolerance test and methacholine challenge test with normal results, nine healthy subjects 18 to 23 years of age were exposed to filtered air and to 0.18 and 0.30 ppm NO{sub 2} for 30 min on different days while exercising on a treadmill. Pulmonary function parameters were measured before and after each exposure.more » In this study, no statistically significant changes were observed in FEV1, RT PEFR, and Vmax50% after exposure to 0.18 and 0.30 ppm NO{sub 2}. For these selected healthy athletes, short-term exposure to ambient NO{sub 2} levels during heavy exercise does not affect adversely the pulmonary function.« less

Occupation, hobbies, and acute leukemia in adults.

PubMed

Terry, Paul D; Shore, David L; Rauscher, Garth H; Sandler, Dale P

2005-10-01

Occupational and industrial exposures have been implicated in the etiology of leukemia, yet uncertainty remains regarding potential high risk occupations. We examined the associations between self-reported occupations and hobbies and acute leukemia risk using data from 811 cases and 637 controls participating in a case-control study in the U.S. and Canada. We found that several occupations may increase the risk of acute leukemia, particularly occupations related to petroleum products, rubber, nuclear energy, munitions, plastics, and electronics manufacturing. Differences were noted according to histological type. Other occupations and hobbies were not clearly associated with risk.

Acidic Mammalian Chitinase Negatively Affects Immune Responses during Acute and Chronic Aspergillus fumigatus Exposure.

PubMed

Garth, Jaleesa M; Mackel, Joseph J; Reeder, Kristen M; Blackburn, Jonathan P; Dunaway, Chad W; Yu, Zhihong; Matalon, Sadis; Fitz, Lori; Steele, Chad

2018-07-01

Chitin is a polysaccharide that provides structure and rigidity to the cell walls of fungi and insects. Mammals possess multiple chitinases, which function to degrade chitin, thereby supporting a role for chitinases in immune defense. However, chitin degradation has been implicated in the pathogenesis of asthma. Here, we determined the impact of acidic mammalian chitinase (AMCase) ( Chia ) deficiency on host defense during acute exposure to the fungal pathogen Aspergillus fumigatus as well as its contribution to A. fumigatus -associated allergic asthma. We demonstrate that chitin in the fungal cell wall was detected at low levels in A. fumigatus conidia, which emerged at the highest level during hyphal transition. In response to acute A. fumigatus challenge, Chia -/- mice unexpectedly demonstrated lower A. fumigatus lung burdens at 2 days postchallenge. The lower fungal burden correlated with decreased lung interleukin-33 (IL-33) levels yet increased IL-1β and prostaglandin E 2 (PGE 2 ) production, a phenotype that we reported previously to promote the induction of IL-17A and IL-22. During chronic A. fumigatus exposure, AMCase deficiency resulted in lower dynamic and airway lung resistance than in wild-type mice. Improved lung physiology correlated with attenuated levels of the proallergic chemokines CCL17 and CCL22. Surprisingly, examination of inflammatory responses during chronic exposure revealed attenuated IL-17A and IL-22 responses, but not type 2 responses, in the absence of AMCase. Collectively, these data suggest that AMCase functions as a negative regulator of immune responses during acute fungal exposure and is a contributor to fungal asthma severity, putatively via the induction of proinflammatory responses. Copyright © 2018 American Society for Microbiology.

Noninvasive Biomonitoring Approaches to Determine Dosimetry and Risk Following Acute Chemical Exposure: Analysis of Lead or Organophosphate Insecticide in Saliva

DOE Office of Scientific and Technical Information (OSTI.GOV)

Timchalk, Chuck; Poet, Torka S.; Kousba, Ahmed A.

2004-04-01

There is a need to develop approaches for assessing risk associated with acute exposures to a broad-range of chemical agents and to rapidly determine the potential implications to human health. Non-invasive biomonitoring approaches are being developed using reliable portable analytical systems to quantitate dosimetry utilizing readily obtainable body fluids, such as saliva. Saliva has been used to evaluate a broad range of biomarkers, drugs, and environmental contaminants including heavy metals and pesticides. To advance the application of non-invasive biomonitoring a microfluidic/ electrochemical device has also been developed for the analysis of lead (Pb), using square wave anodic stripping voltammetry. Themore » system demonstrates a linear response over a broad concentration range (1 2000 ppb) and is capable of quantitating saliva Pb in rats orally administered acute doses of Pb-acetate. Appropriate pharmacokinetic analyses have been used to quantitate systemic dosimetry based on determination of saliva Pb concentrations. In addition, saliva has recently been used to quantitate dosimetry following exposure to the organophosphate insecticide chlorpyrifos in a rodent model system by measuring the major metabolite, trichloropyridinol, and saliva cholinesterase inhibition following acute exposures. These results suggest that technology developed for non-invasive biomonitoring can provide a sensitive, and portable analytical tool capable of assessing exposure and risk in real-time. By coupling these non-invasive technologies with pharmacokinetic modeling it is feasible to rapidly quantitate acute exposure to a broad range of chemical agents. In summary, it is envisioned that once fully developed, these monitoring and modeling approaches will be useful for accessing acute exposure and health risk.« less

TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

EPA Science Inventory

The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

The effects of acute pesticide exposure on neuroblastoma cells chronically exposed to diazinon.

PubMed

Axelrad, J C; Howard, C V; McLean, W G

2003-03-14

Speculation about potential neurotoxicity due to chronic exposure to low doses of organophosphate (OP) pesticides is not yet supported by experimental evidence. The objective of this work was to use a cell culture model of chronic OP exposure to determine if such exposure can alter the sensitivity of nerve cells to subsequent acute exposure to OPs or other compounds. NB2a neuroblastoma cells were grown in the presence of 25 microM diazinon for 8 weeks. The OP was then withdrawn and the cells were induced to differentiate in the presence of various other pesticides or herbicides, including OPs and OP-containing formulations. The resulting outgrowth of neurite-like structures was measured by light microscopy and quantitative image analysis and the IC(50) for each OP or formulation was calculated. The IC(50) values in diazinon-pre-exposed cells were compared with the equivalent values in cells not pre-exposed to diazinon. The IC(50) for inhibition of neurite outgrowth by acute application of diazinon, pyrethrum, glyphosate or a commercial formulation of glyphosate was decreased by between 20 and 90% after pre-treatment with diazinon. In contrast, the IC(50) for pirimiphos methyl was unaffected and those for phosmet or chlorpyrifos were increased by between 1.5- and 3-fold. Treatment of cells with chlorpyrifos or with a second glyphosate-containing formulation led to the formation of abnormal neurite-like structures in diazinon-pre-exposed cells. The data support the view that chronic exposure to an OP may reduce the threshold for toxicity of some, but by no means all, environmental agents.

Childhood leukaemia near nuclear sites in Belgium, 2002–2008

PubMed Central

Bollaerts, Kaatje; Simons, Koen; Van Bladel, Lodewijk; De Smedt, Tom; Sonck, Michel; Fierens, Sébastien; Poffijn, André; Geraets, David; Gosselin, Pol; Van Oyen, Herman; Francart, Julie

2018-01-01

This paper describes an ecological study investigating whether there is an excess incidence of acute leukaemia among children aged 0–14 years living in the vicinity of the nuclear sites in Belgium. Poisson regression modelling was carried out for proximity areas of varying sizes. In addition, the hypothesis of a gradient in leukaemia incidence with increasing levels of surrogate exposures was explored by means of focused hypothesis tests and generalized additive models. For the surrogate exposures, three proxies were used, that is, residential proximity to the nuclear site, prevailing winds and simulated radioactive discharges, on the basis of mathematical dispersion modelling. No excess incidence of acute leukaemia was observed around the nuclear power plants of Doel or Tihange nor around the nuclear site of Fleurus, which is a major manufacturer of radioactive isotopes in Europe. Around the site of Mol-Dessel, however, two- to three-fold increased leukaemia incidence rates were found in children aged 0–14 years living in the 0–5, 0–10 and the 0–15 km proximity areas. For this site, there was evidence for a gradient in leukaemia incidence with increased proximity, prevailing winds and simulated radioactive discharges, suggesting a potential link with the site that needs further investigation. An increased incidence of acute leukaemia in children aged 0–14 years was observed around one nuclear site that hosted reprocessing activities in the past and where nuclear research activities and radioactive waste treatment are ongoing. PMID:27380513

Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure.

PubMed

Thompson, Gary L; Roth, Caleb C; Kuipers, Marjorie A; Tolstykh, Gleb P; Beier, Hope T; Ibey, Bennett L

2016-01-29

Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus - histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. Copyright © 2015 Elsevier Inc. All rights reserved.

Acute pulmonary toxicity following inhalation exposure to aerosolized VX in anesthetized rats.

PubMed

Peng, Xinqi; Perkins, Michael W; Simons, Jannitt; Witriol, Alicia M; Rodriguez, Ashley M; Benjamin, Brittany M; Devorak, Jennifer; Sciuto, Alfred M

2014-06-01

This study evaluated acute toxicity and pulmonary injury in rats at 3, 6 and 24 h after an inhalation exposure to aerosolized O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX). Anesthetized male Sprague-Dawley rats (250-300 g) were incubated with a glass endotracheal tube and exposed to saline or VX (171, 343 and 514 mg×min/m³ or 0.2, 0.5 and 0.8 LCt₅₀, respectively) for 10 min. VX was delivered by a small animal ventilator at a volume of 2.5 ml × 70 breaths/minute. All VX-exposed animals experienced a significant loss in percentage body weight at 3, 6, and 24 h post-exposure. In comparison to controls, animals exposed to 514 mg×min/m³ of VX had significant increases in bronchoalveolar lavage (BAL) protein concentrations at 6 and 24 h post-exposure. Blood acetylcholinesterase (AChE) activity was inhibited dose dependently at each of the times points for all VX-exposed groups. AChE activity in lung homogenates was significantly inhibited in all VX-exposed groups at each time point. All VX-exposed animals assessed at 20 min and 3, 6 and 24 h post-exposure showed increases in lung resistance, which was prominent at 20 min and 3 h post-exposure. Histopathologic evaluation of lung tissue of the 514 mg×min/m³ VX-exposed animals at 3, 6 and 24 h indicated morphological changes, including perivascular inflammation, alveolar exudate and histiocytosis, alveolar septal inflammation and edema, alveolar epithelial necrosis, and bronchiolar inflammatory infiltrates, in comparison to controls. These results suggest that aerosolization of the highly toxic, persistent chemical warfare nerve agent VX results in acute pulmonary toxicity and lung injury in rats.

Gene expression-based dosimetry by dose and time in mice following acute radiation exposure.

PubMed

Tucker, James D; Divine, George W; Grever, William E; Thomas, Robert A; Joiner, Michael C; Smolinski, Joseph M; Auner, Gregory W

2013-01-01

Rapid and reliable methods for performing biological dosimetry are of paramount importance in the event of a large-scale nuclear event. Traditional dosimetry approaches lack the requisite rapid assessment capability, ease of use, portability and low cost, which are factors needed for triaging a large number of victims. Here we describe the results of experiments in which mice were acutely exposed to (60)Co gamma rays at doses of 0 (control) to 10 Gy. Blood was obtained from irradiated mice 0.5, 1, 2, 3, 5, and 7 days after exposure. mRNA expression levels of 106 selected genes were obtained by reverse-transcription real time PCR. Stepwise regression of dose received against individual gene transcript expression levels provided optimal dosimetry at each time point. The results indicate that only 4-7 different gene transcripts are needed to explain ≥ 0.69 of the variance (R(2)), and that receiver-operator characteristics, a measure of sensitivity and specificity, of ≥ 0.93 for these statistical models were achieved at each time point. These models provide an excellent description of the relationship between the actual and predicted doses up to 6 Gy. At doses of 8 and 10 Gy there appears to be saturation of the radiation-response signals with a corresponding diminution of accuracy. These results suggest that similar analyses in humans may be advantageous for use in a field-portable device designed to assess exposures in mass casualty situations.

Resistin deficiency in mice has no effect on pulmonary responses induced by acute ozone exposure

PubMed Central

Razvi, Shehla S.; Richards, Jeremy B.; Malik, Farhan; Cromar, Kevin R.; Price, Roger E.; Bell, Cynthia S.; Weng, Tingting; Atkins, Constance L.; Spencer, Chantal Y.; Cockerill, Katherine J.; Alexander, Amy L.; Blackburn, Michael R.; Alcorn, Joseph L.; Haque, Ikram U.

2015-01-01

Acute exposure to ozone (O3), an air pollutant, causes pulmonary inflammation, airway epithelial desquamation, and airway hyperresponsiveness (AHR). Pro-inflammatory cytokines—including IL-6 and ligands of chemokine (C-X-C motif) receptor 2 [keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-2], TNF receptor 1 and 2 (TNF), and type I IL-1 receptor (IL-1α and IL-1β)—promote these sequelae. Human resistin, a pleiotropic hormone and cytokine, induces expression of IL-1α, IL-1β, IL-6, IL-8 (the human ortholog of murine KC and MIP-2), and TNF. Functional differences exist between human and murine resistin; yet given the aforementioned observations, we hypothesized that murine resistin promotes O3-induced lung pathology by inducing expression of the same inflammatory cytokines as human resistin. Consequently, we examined indexes of O3-induced lung pathology in wild-type and resistin-deficient mice following acute exposure to either filtered room air or O3. In wild-type mice, O3 increased bronchoalveolar lavage fluid (BALF) resistin. Furthermore, O3 increased lung tissue or BALF IL-1α, IL-6, KC, TNF, macrophages, neutrophils, and epithelial cells in wild-type and resistin-deficient mice. With the exception of KC, which was significantly greater in resistin-deficient compared with wild-type mice, no genotype-related differences in the other indexes existed following O3 exposure. O3 caused AHR to acetyl-β-methylcholine chloride (methacholine) in wild-type and resistin-deficient mice. However, genotype-related differences in airway responsiveness to methacholine were nonexistent subsequent to O3 exposure. Taken together, these data demonstrate that murine resistin is increased in the lungs of wild-type mice following acute O3 exposure but does not promote O3-induced lung pathology. PMID:26386120

Proposed standards for acute exposure to low enrichment uranium for compliance with 10 CFR 70.61.

PubMed

Kathren, Ronald L; Burklin, Richard K

2008-08-01

Title 10, Code of Federal Regulations Part 70, puts forth requirements for licensure of special nuclear material including specific risk criteria for acute intakes based on biological effects. Standards for acute oral and inhalation intakes of soluble low enrichment are proposed for the three levels of biological effects given in the regulations. These levels were developed largely from available human data and have a large measure of conservatism. The proposed threshold for life endangerment was 500 mg for acute inhalation intakes and 2,500 mg for acute ingestion intakes. Acute intakes of 1,400 mg for ingestion and 100 mg for inhalation are proposed as thresholds for irreversible or serious long lasting health effects. For minor transient health effects, the proposed levels are 410 and 30 mg, respectively, for acute ingestion and inhalation intakes. For acute intakes below these levels, no demonstrable toxicological effects are anticipated.

The significance of nanomaterial post-exposure responses in Daphnia magna standard acute immobilisation assay: Example with testing TiO2 nanoparticles.

PubMed

Novak, Sara; Jemec Kokalj, Anita; Hočevar, Matej; Godec, Matjaž; Drobne, Damjana

2018-05-15

One of the most widely used aquatic standarized tests for the toxicity screening of chemicals is the acute toxicity test with the freshwater crustacean Daphnia magna, which has also been applied in the toxicity screening of manufactured nanoparticles (NPs). However, in the case of non-soluble NPs most of the results of this test have showed no effect. The aim of the work presented here was to modify the standardized test by the least possible extent to make it more sensitive for non-soluble particles. The standard acute immobilisation assay with daphnids was modified by prolonging the exposure period and by measuring additional endpoints. Daphnids were exposed to TiO 2 NPs in a standard acute test (48h of exposure), a standard acute test (48h of exposure) followed by 24h recovery period in clean medium or a prolonged exposure in the NPs solutions totaling 72h. Together with immobility, the adsorption of NPs to body surfaces was also observed as an alternative measure of the NPs effects. Our results showed almost no effect of TiO 2 NPs on D. magna after the 48h standard acute test, while immobility was increased when the exposure period to TiO 2 NPs was prolonged from 48h to 72h. Even when daphnids were transferred to clean medium for additional 24h after 48h of exposure to TiO 2 NPs the immobility increased. We conclude that by transferring the daphnids to clean medium at the end of the 48h exposure to TiO 2 NPs, the delayed effects of the tested material can be seen. This methodological step could improve the sensitivity of D. magna test as a model in nanomaterial environmental risk assessment. Copyright © 2018 Elsevier Inc. All rights reserved.

Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study)

PubMed Central

Perez-Saldivar, Maria Luisa; Ortega-Alvarez, Manuel Carlos; Fajardo-Gutierrez, Arturo; Bernaldez-Rios, Roberto; del Campo-Martinez, Maria de los Angeles; Medina-Sanson, Aurora; Palomo-Colli, Miguel Angel; Paredes-Aguilera, Rogelio; Martínez-Avalos, Armando; Borja-Aburto, Victor Hugo; Rodriguez-Rivera, Maria de Jesus; Vargas-Garcia, Victor Manuel; Zarco-Contreras, Jesus; Flores-Lujano, Janet; Mejia-Arangure, Juan Manuel

2008-01-01

Background Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL) in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring. Methods From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR) of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s). In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI) was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an expert's opinion. Results The

Occupational exposure levels of bioaerosol components are associated with serum levels of the acute phase protein Serum Amyloid A in greenhouse workers.

PubMed

Madsen, Anne Mette; Thilsing, Trine; Bælum, Jesper; Garde, Anne Helene; Vogel, Ulla

2016-01-20

Occupational exposure to particles may be associated with increased inflammation of the airways. Animal experiments suggest that inhaled particles also induce a pulmonary acute phase response, leading to systemic circulation of acute phase proteins. Greenhouse workers are exposed to elevated levels of bioaerosols. The objective of this study is to assess whether greenhouse workers personal exposure to bioaerosol components was associated with serum levels of the acute phase proteins Serum Amyloid A (SAA) and C-reactive protein (CRP). SAA and CRP levels were determined in serum sampled repeatedly from 33 greenhouse workers. Blood was drawn repeatedly on Mondays and Thursdays during work weeks. Acute phase protein levels were compared to levels in a comparison group of 42 people and related to individual exposure levels to endotoxin, dust, bacteria, fungi and β-glucan. Serum levels of SAA and CRP were not significantly different in greenhouse workers and a reference group, or on the two work days. In a mixed model, SAA levels were positively associated with endotoxin exposure levels (p = 0.0007). Results for fungi were not clear. CRP levels were positively associated with endotoxin exposures (p = 0.022). Furthermore, when workers were categorized into three groups based on SAA and CRP serum levels endotoxin exposure was highest in the group with the highest SAA levels and in the group with middle and highest CRP levels. SAA and CRP levels were elevated in workers with asthma. Greenhouse workers did not have elevated serum levels of SAA and CRP compared to a reference group. However, occupational exposure to endotoxin was positively associated with serum levels of the acute phase proteins SAA and CRP. Preventive measures to reduce endotoxin exposure may be beneficial.

Medical Countermeasures for Radiation Exposure and Related Injuries: Characterization of Medicines, FDA-Approval Status and Inclusion into the Strategic National Stockpile

PubMed Central

Singh, Vijay K.; Romaine, Patricia L.P.; Seed, Thomas M.

2015-01-01

Abstract World events over the past decade have highlighted the threat of nuclear terrorism as well as an urgent need to develop radiation countermeasures for acute radiation exposures and subsequent bodily injuries. An increased probability of radiological or nuclear incidents due to detonation of nuclear weapons by terrorists, sabotage of nuclear facilities, dispersal and exposure to radioactive materials, and accidents provides the basis for such enhanced radiation exposure risks for civilian populations. Although the search for suitable radiation countermeasures for radiation-associated injuries was initiated more than half a century ago, no safe and effective radiation countermeasure for the most severe of these injuries, namely acute radiation syndrome (ARS), has been approved by the United States Food and Drug Administration (FDA). The dearth of FDA-approved radiation countermeasures has prompted intensified research for a new generation of radiation countermeasures. In this communication, the authors have listed and reviewed the status of radiation countermeasures that are currently available for use, or those that might be used for exceptional nuclear/radiological contingencies, plus a limited few medicines that show early promise but still remain experimental in nature and unauthorized for human use by the FDA. PMID:25905522

Acute neurological symptoms during hypobaric exposure: consider cerebral air embolism.

PubMed

Weenink, Robert P; Hollmann, Markus W; van Hulst, Robert A

2012-11-01

Cerebral arterial gas embolism (CAGE) is well known as a complication of invasive medical procedures and as a risk in diving and submarine escape. In the underwater environment, CAGE is caused by trapped air, which expands and leads to lung vessel rupture when ambient pressure decreases during ascent. Pressure decrease also occurs during hypobaric activities such as flying and, therefore, CAGE may theoretically be a risk in hypobaric exposure. We reviewed the available literature on this subject. Identified were 12 cases of CAGE due to hypobaric exposure. Based on these cases, we discuss pathophysiology, diagnosis, and treatment of CAGE due to hypobaric exposure. The low and slow pressure decrease during most hypobaric activities (as opposed to diving) account for the low incidence of CAGE during these exposures and suggest that severe air trapping must be present to cause barotrauma. This is also suggested by the large prevalence of air filled cysts in the case reports reviewed. We recommend considering CAGE in all patients presenting with acute central neurological injury during or shortly after pressure decrease such as flying. A CT scan of head and chest should be performed in these patients. Treatment with hyperbaric oxygen therapy should be initiated as soon as possible in cases of proven or probable CAGE.

Chronic and acute exposures to the world trade center disaster and lower respiratory symptoms: area residents and workers.

PubMed

Maslow, Carey B; Friedman, Stephen M; Pillai, Parul S; Reibman, Joan; Berger, Kenneth I; Goldring, Roberta; Stellman, Steven D; Farfel, Mark

2012-06-01

We assessed associations between new-onset (post-September 11, 2001 [9/11]) lower respiratory symptoms reported on 2 surveys, administered 3 years apart, and acute and chronic 9/11-related exposures among New York City World Trade Center-area residents and workers enrolled in the World Trade Center Health Registry. World Trade Center-area residents and workers were categorized as case participants or control participants on the basis of lower respiratory symptoms reported in surveys administered 2 to 3 and 5 to 6 years after 9/11. We created composite exposure scales after principal components analyses of detailed exposure histories obtained during face-to-face interviews. We used multivariate logistic regression models to determine associations between lower respiratory symptoms and composite exposure scales. Both acute and chronic exposures to the events of 9/11 were independently associated, often in a dose-dependent manner, with lower respiratory symptoms among individuals who lived and worked in the area of the World Trade Center. Study findings argue for detailed assessments of exposure during and after events in the future from which potentially toxic materials may be released and for rapid interventions to minimize exposures and screen for potential adverse health effects.

Acute inhalative exposure assessment: derivation of guideline levels with special regard to sensitive subpopulations and time scaling.

PubMed

Mielke, Hans; Gundert, Anna; Abraham, Klaus; Gundert-Remy, Ursula

2005-10-30

Risk assessment for acute airborne exposure to volatile organic compounds (VOCs), including exposure to chemical warfare agents, requires consideration of local and systemic effects at high concentrations. The operating procedure developed by the US Acute Exposure Guideline Level (AEGL) committee has gained special attention, in part because of the international collaboration in the project. The procedure defines three levels (AEGL-1: discomfort; AEGL-2: irreversible or other serious, long-lasting adverse effects; AEGL-3: life-threatening effects or death) for different exposure times (10 and 30 min, and 1, 4 and 8 h). In this article, the methodology for deriving AEGL values is reported. Extending the areas covered by the existing AEGL methodology, sensitive subpopulations are dealt with in more detail. Sensitive persons are expected to suffer from stronger effects when exposed to a given external concentration. Using a kinetic model with the sample substance dichloromethane (DCM), the higher internal exposure of children is quantified and compared to a healthy, young adult. The difference is shown to depend on age, on dose, and on duration of exposure. Furthermore, several ways are presented to derive AEGL values for exposure times which differ from the exposure duration in animal studies ('time scaling'). In comparison to the conventional procedure, the alternative approaches are based on mechanistic models of the toxicodynamic effect. Use of these models results in AEGL values which are biologically justified.

Cutaneous exposure to vesicant phosgene oxime: Acute effects on the skin and systemic toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tewari-Singh, Neera, E-mail: Neera.tewari-singh@uc

Phosgene Oxime (CX), an urticant or nettle agent categorized as a vesicant, is a potential chemical warfare and terrorist weapon. Its exposure can result in widespread and devastating effects including high mortality due to its fast penetration and ability to cause immediate severe cutaneous injury. It is one of the least studied chemical warfare agents with no effective therapy available. Thus, our goal was to examine the acute effects of CX following its cutaneous exposure in SKH-1 hairless mice to help establish a relevant injury model. Results from our study show that topical cutaneous exposure to CX vapor causes blanchingmore » of exposed skin with an erythematous ring, necrosis, edema, mild urticaria and erythema within minutes after exposure out to 8 h post-exposure. These clinical skin manifestations were accompanied with increases in skin thickness, apoptotic cell death, mast cell degranulation, myeloperoxidase activity indicating neutrophil infiltration, p53 phosphorylation and accumulation, and an increase in COX-2 and TNFα levels. Topical CX-exposure also resulted in the dilatation of the peripheral vessels with a robust increase in RBCs in vessels of the liver, spleen, kidney, lungs and heart tissues. These events could cause a drop in blood pressure leading to shock, hypoxia and death. Together, this is the first report on effects of CX cutaneous exposure, which could help design further comprehensive studies evaluating the acute and chronic skin injuries from CX topical exposure and elucidate the related mechanism of action to aid in the identification of therapeutic targets and mitigation of injury. - Highlights: • Phosgene oxime cutaneous exposure causes skin blanching, edema and urticaria. • Penetration of phosgene oxime causes dilation of vasculature in internal organs. • Mast cells could play an important role in phosgene oxime-induced skin injury. • Phosgene oxime could induce low blood pressure and hypoxia leading to mortality. �

[Effects of acute exposure to high altitude on hepatic function and CYP1A2 and CYP3A4 activities in rats].

PubMed

Li, Wenbin; Jia, Zhengping; Xie, Hua; Zhang, Juanhong; Wang, Yanling; Hao, Ying; Wang, Rong

2014-07-01

To investigate the changes in hepatic functions and activities of CYP1A2 and CYP3A4 in rats after acute exposure to high altitude. Twelve healthy male Wistar rats were randomly divided into control group and exposure group for acute exposure to normal and high altitude (4010 m) environment. Blood samples were collected from the vena orbitalis posterior for detection of the hepatic function. Hepatic pathologies of the rats were examined microscopically with HE staining. Liver microsomes were extracted by differential centrifugation to assess the activities of CYP1A2 and 3A4 using P450-GloTM kit. In rats with acute exposure to high altitude, AST, ALT, and ALP all increased significantly by 48.50%, 47.90%, and 103.02%, respectively, and TP decreased significantly by 17.80% as compared with those in rats maintained in normal altitude environment (P<0.05). Pathological examination of the liver revealed edema of the central vein of the liver and hepatocyte karyopyknosis in rats after acute exposure to high altitude, which also resulted in significantly lowered activities of CYP1A2 and 3A4 in the liver (by 96.56% and 43.53%, respectively). Acute exposure to high altitude can cause obvious liver injuries and lowered activities of CYP1A2 and 3A4 in rats to severely affect drug metabolism in the liver and result in increased concentration, prolonged half-life and reduced clearance of drugs.

In utero exposure to lipopolysaccharide alters the postnatal acute phase response in beef heifers

USDA-ARS?s Scientific Manuscript database

This study was designed to determine the potential effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal acute phase response (APR) to an LPS challenge in heifers. Pregnant crossbred cows (n = 50) were separated into prenatal immune stimulation (PIS; n = 25; administered 0.1 microgr...

Medical countermeasures for unwanted CBRN exposures: part II radiological and nuclear threats with review of recent countermeasure patents

PubMed Central

Singh, Vijay K.; Romaine, Patricia L.P.; Newman, Victoria L.; Seed, Thomas M.

2016-01-01

ABSTRACT Introduction: The global threat of a chemical, biological, radiological, or nuclear (CBRN) disaster is an important priority for all government agencies involved in domestic security and public health preparedness. Radiological/nuclear (RN) attacks or accidents have become a larger focus of the United States Food and Drug administration (US FDA) over time because of their increased likeliness. Clinical signs and symptoms of a developing acute radiation syndrome (ARS) are grouped into three sub-syndromes named for the dominant organ system affected, namely the hematopoietic (H-ARS), gastrointestinal (GI-ARS), and neurovascular systems. The availability of safe and effective countermeasures against radiological/nuclear threats currently represents a significant unmet medical need. Areas covered: This article reviews the development of RN threat medical countermeasures and highlights those specific countermeasures that have been recently patented and approved following the FDA Animal Rule. Patents for such agents from 2015 have been presented. Expert opinion: Two granulocyte colony-stimulating factor (G-CSF)-based radiation countermeasures (Neupogen® (Amgen, Thousand Oaks, CA) and Neulasta® (Amgen, Thousand Oaks, CA)) have recently been approved by the FDA for treatment of H-ARS and both these agents are radiomitigators, used after radiation exposure. To date, there are no FDA-approved radioprotectors for ARS. PMID:27610458

Acute and Fractionated Exposure to High-LET 56Fe HZE-Particle Radiation Both Result in Similar Long-Term Deficits in Adult Hippocampal Neurogenesis

PubMed Central

Rivera, Phillip D.; Shih, Hung-Ying; LeBlanc, Junie A.; Cole, Mara G.; Amaral, Wellington Z.; Mukherjee, Shibani; Zhang, Shichuan; Lucero, Melanie J.; DeCarolis, Nathan A.; Chen, Benjamin P. C.; Eisch, Amelia J.

2014-01-01

Astronauts on multi-year interplanetary missions will be exposed to a low, chronic dose of high-energy, high-charge particles. Studies in rodents show acute, nonfractionated exposure to these particles causes brain changes such as fewer adult-generated hippocampal neurons and stem cells that may be detrimental to cognition and mood regulation and thus compromise mission success. However, the influence of a low, chronic dose of these particles on neurogenesis and stem cells is unknown. To examine the influence of galactic cosmic radiation on neurogenesis, adult-generated stem and progenitor cells in Nestin-CreERT2/R26R-YFP transgenic mice were inducibly labeled to allow fate tracking. Mice were then sham exposed or given one acute 100 cGy 56Fe-particle exposure or five fractionated 20 cGy 56Fe-particle exposures. Adult-generated hippocampal neurons and stem cells were quantified 24 h or 3 months later. Both acute and fractionated exposure decreased the amount of proliferating cells and immature neurons relative to sham exposure. Unexpectedly, neither acute nor fractionated exposure decreased the number of adult neural stem cells relative to sham expsoure. Our findings show that single and fractionated exposures of 56Fe-particle irradiation are similarly detrimental to adult-generated neurons. Implications for future missions and ground-based studies in space radiation are discussed. PMID:24320054

ESTIMATED RATE OF FATAL AUTOMOBILE ACCIDENTS ATTRIBUTABLE TO ACUTE SOLVENT EXPOSURE AT LOW INHALED CONCENTRATIONS

EPA Science Inventory

Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mecha...

Acute spill-mimicking exposure effect of hexavalent chromium on the pituitary-ovarian axis of a teleost, Channa punctatus (Bloch).

PubMed

Mishra, Ashish K; Mohanty, Banalata

2014-05-01

Acute exposure to hexavalent chromium (as 10, 20, and 40 mg/L potassium dichromate for 96 h) adversely affected the pituitary-ovarian axis of a teleost Channa punctatus. The toxic impact of metal exposure on fish ovary was revealed in the form of increased percentage of atretic follicles, significantly in 20 mg/L and 40 mg/L exposure groups. The follicular atresia mostly occurred in vitellogenic (stage II and stage III) oocytes. Reduction of serum level of 17β-estradiol was also significant in 20 mg/L and 40 mg/L exposure groups. The increase of LH-immunointensity of pituitary gonadotrophs (LHβ-immunoreactive cells) and their hypertrophy was evident, significantly in fish of 40 mg/L exposed group. Thus, the present acute metal spill-mimicking laboratory study clearly demonstrated that short-term exposures to high doses of hexavalent chromium may disrupt reproduction of the fish and affect their population. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

Pulmonary Inflammatory Responses to Acute Meteorite Dust Exposures - to Acute Meteorite Dust Exposures - Exploration

NASA Technical Reports Server (NTRS)

Harrington, A. D.; McCubbin, F. M.; Kaur, J.; Smirnov, A.; Galdanes, K.; Schoonen, M. A. A.; Chen, L. C.; Tsirka, S. E.; Gordon, T.

2017-01-01

New initiatives to begin lunar and martian colonization within the next few decades are illustrative of the resurgence of interest in space travel. One of NASA's major concerns with extended human space exploration is the inadvertent and repeated exposure to unknown dust. This highly interdisciplinary study evaluates both the geochemical reactivity (e.g. iron solubility and acellular reactive oxygen species (ROS) generation) and the relative toxicity (e.g. in vitro and in vivo pulmonary inflammation) of six meteorite samples representing either basalt or regolith breccia on the surface of the Moon, Mars, and Asteroid 4Vesta. Terrestrial mid-ocean ridge basalt (MORB) is also used for comparison. The MORB demonstrated higher geochemical reactivity than most of the meteorite samples but caused the lowest acute pulmonary inflammation (API). Notably, the two martian meteorites generated some of the highest API but only the basaltic sample is significantly reactive geochemically. Furthermore, while there is a correlation between a meteorite's soluble iron content and its ability to generate acellular ROS, there is no direct correlation between a particle's ability to generate ROS acellularly and its ability to generate API. However, assorted in vivo API markers did demonstrate strong positive correlations with increasing bulk Fenton metal content. In summary, this comprehensive dataset allows for not only the toxicological evaluation of astromaterials but also clarifies important correlations between geochemistry and health.

Correlation of IMPDH1 gene polymorphisms with subclinical acute rejection and mycophenolic acid exposure parameters on day 28 after renal transplantation.

PubMed

Kagaya, Hideaki; Miura, Masatomo; Saito, Mitsuru; Habuchi, Tomonori; Satoh, Shigeru

2010-08-01

The risk of acute rejection in patients with higher exposure to mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), might be due to inosine 5'-monophosphate dehydrogenase (IMPDH) polymorphisms. The correlations with subclinical acute rejection, IMPDH1 polymorphisms and MPA exposure on day 28 post-transplantation were investigated in 82 Japanese recipients. Renal transplant recipients were given combination immunosuppressive therapy consisting of tacrolimus and 1.0, 1.5 or 2.0 g/day of MMF in equally divided doses every 12 hr at designated times. There were no significant differences in the incidence of subclinical acute rejection between IMPDH1 rs2278293 or rs2278294 polymorphisms (p = 0.243 and 0.735, respectively). However, in the high MPA night-time exposure range (AUC > 60 microg x h/ml and C(0 )> or = 1.9 microg/ml), there was a significant difference in the incidence of subclinical acute rejection between IMPDH1 rs2278293 A/A, A/G and G/G genotypes (each p = 0.019), but not the IMPDH1 rs2278294 genotype. In the higher daytime MPA exposure range, patients with the IMPDH1 rs2278293 G/G genotype also tended to develop subclinical acute rejection. In patients with the IMPDH rs2278293 A/A genotype, the risk of subclinical acute rejection episode tends to be low and the administration of MMF was effective. The risk of subclinical acute rejection for recipients who cannot adapt in therapeutic drug monitoring (TDM) of MPA seems to be influenced by IMPDH1 rs2278293 polymorphism. The prospective analysis of IMPDH1 rs2278293 polymorphism as well as monitoring of MPA plasma concentration after transplantation might help to improve MMF therapy.

Chronic and Acute Exposures to the World Trade Center Disaster and Lower Respiratory Symptoms: Area Residents and Workers

PubMed Central

Friedman, Stephen M.; Pillai, Parul S.; Reibman, Joan; Berger, Kenneth I.; Goldring, Roberta; Stellman, Steven D.; Farfel, Mark

2012-01-01

Objectives. We assessed associations between new-onset (post–September 11, 2001 [9/11]) lower respiratory symptoms reported on 2 surveys, administered 3 years apart, and acute and chronic 9/11-related exposures among New York City World Trade Center–area residents and workers enrolled in the World Trade Center Health Registry. Methods. World Trade Center–area residents and workers were categorized as case participants or control participants on the basis of lower respiratory symptoms reported in surveys administered 2 to 3 and 5 to 6 years after 9/11. We created composite exposure scales after principal components analyses of detailed exposure histories obtained during face-to-face interviews. We used multivariate logistic regression models to determine associations between lower respiratory symptoms and composite exposure scales. Results. Both acute and chronic exposures to the events of 9/11 were independently associated, often in a dose-dependent manner, with lower respiratory symptoms among individuals who lived and worked in the area of the World Trade Center. Conclusions. Study findings argue for detailed assessments of exposure during and after events in the future from which potentially toxic materials may be released and for rapid interventions to minimize exposures and screen for potential adverse health effects. PMID:22515865

Medical management of three workers following a radiation exposure incident

DOE Office of Scientific and Technical Information (OSTI.GOV)

House, R.A.; Sax, S.E.; Rumack, E.R.

The medical management of three individuals involved in an exposure incident to whole-body radiation at a nuclear generating plant of a Canadian electrical utility is described. The exposure incident resulted in the two highest whole-body radiation doses ever received in a single event by workers in a Canadian nuclear power plant. The individual whole-body doses (127.4 mSv, 92.0 mSv, 22.4 mSv) were below the threshold for acute radiation sickness but the exposures still presented medical management problems related to assessment and counseling. Serial blood counting and lymphocyte cytogenetic analysis to corroborate the physical dosimetry were performed. All three employees experiencedmore » somatic symptoms due to stress and one employee developed post-traumatic stress disorder. This incident indicates that there is a need in such radiation exposure accidents for early and continued counseling of exposed employees to minimize the risk of development of stress-related symptoms.« less

Adverse Cardiovascular Effects with Acute Particulate Matter and Ozone Exposures: Interstrain Variation in Mice

PubMed Central

Hamade, Ali K.; Rabold, Richard; Tankersley, Clarke G.

2008-01-01

Objectives Increased ambient particulate matter (PM) levels are associated with cardiovascular morbidity and mortality, as shown by numerous epidemiology studies. Few studies have investigated the role of copollutants, such as ozone, in this association. Furthermore, the mechanisms by which PM affects cardiac function remain uncertain. We hypothesized that PM and O3 induce adverse cardiovascular effects in mice and that these effects are strain dependent. Study design After implanting radiotelemeters to measure heart rate (HR) and HR variability (HRV) parameters, we exposed C57Bl/6J (B6), C3H/HeJ (HeJ), and C3H/HeOuJ (OuJ) inbred mouse strains to three different daily exposures of filtered air (FA), carbon black particles (CB), or O3 and CB sequentially [O3CB; for CB, 536 ± 24 μg/m3; for O3, 584 ± 35 ppb (mean ± SE)]. Results We observed significant changes in HR and HRV in all strains due to O3CB exposure, but not due to sequential FA and CB exposure (FACB). The data suggest that primarily acute HR and HRV effects occur during O3CB exposure, especially in HeJ and OuJ mice. For example, HeJ and OuJ mice demonstrated dramatic increases in HRV parameters associated with marked brady-cardia during O3CB exposure. In contrast, depressed HR responses occurred in B6 mice without detectable changes in HRV parameters. Conclusions These findings demonstrate that important interstrain differences exist with respect to PM- and O3-induced cardiac effects. This interstrain variation suggests that genetic factors may modulate HR regulation in response to and recuperation from acute copollutant exposures. PMID:18709144

Estimated rate of fatal automobile accidents attributable to acute solvent exposure at low inhaled concentrations.

PubMed

Benignus, Vernon A; Bushnell, Philip J; Boyes, William K

2011-12-01

Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mechanisms. These observations, along with the extensive data on the relationship between ethanol consumption and fatal automobile accidents, suggested a way to estimate the probability of fatal automobile accidents from solvent inhalation. The problem can be approached using the logic of the algebraic transitive postulate of equality: if A=B and B=C, then A=C. We first calculated a function describing the internal doses of solvent vapors that cause the same magnitude of behavioral impairment as ingestion of ethanol (A=B). Next, we fit a function to data from the literature describing the probability of fatal car crashes for a given internal dose of ethanol (B=C). Finally, we used these two functions to generate a third function to estimate the probability of a fatal car crash for any internal dose of organic solvent vapor (A=C). This latter function showed quantitatively (1) that the likelihood of a fatal car crash is increased by acute exposure to organic solvent vapors at concentrations less than 1.0 ppm, and (2) that this likelihood is similar in magnitude to the probability of developing leukemia from exposure to benzene. This approach could also be applied to other potentially adverse consequences of acute exposure to solvents (e.g., nonfatal car crashes, property damage, and workplace accidents), if appropriate data were available. © 2011 Society for Risk Analysis Published 2011. This article is a U.S. Government work and is in the public domain for the U.S.A.

[Myocardial ultrastructural changes in rats following different levels of acute +Gz exposure].

PubMed

Zheng, Jun; Liu, Cheng-gang; Ren, Li; Xiao, Xiao-guang; Xu, Shu-xuan; Wang, Ping; Ji, Gui-ying

2004-06-01

To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.

Acute and subchronic inhalation exposures of hamsters to nickel-enriched fly ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehner, A.P.; Moss, O.R.; Milliman, E.M.

1979-08-01

One 6-h inhalation exposure of hamsters to Ni-enriched fly ash (NEFA) aerosol (respirable aerosol concentration approx. 200 ..mu..g/liter) deposited about 80 ..mu..g in the deep lung, of which 75 ..mu..g was still present 30 days postexposure. The animals tolerated the exposure well during the 30-day postexposure observation period. Two-month exposures of hamsters to NEFA or fly ash (FA) aerosols (approx. 185 ..mu..g/liter) resuled in a deep lung burden of about 5.7 mg, dark discoloration of lungs, heavily dust-laden macrophages, and significantly higher lung weights than in controls, but only minimal inflammatory reaction and no deaths. There was no difference betweenmore » NEFA and FA effects. The NEFA contained 9% Ni; FA contained 0.03% Ni. The results of this study indicate low acute and subchronic toxicity and slow lung clearance of NEFA and FA.« less

Cigarette Smoke Exposure and the Acute Respiratory Distress Syndrome

PubMed Central

Calfee, Carolyn S.; Matthay, Michael A.; Kangelaris, Kirsten N.; Siew, Edward D.; Janz, David R; Bernard, Gordon R.; May, Addison K; Jacob, Peyton; Havel, Christopher; Benowitz, Neal L.; Ware, Lorraine B.

2016-01-01

Objective The association between cigarette smoke exposure and the acute respiratory distress syndrome (ARDS) in patients with the most common ARDS risk factors of sepsis, pneumonia, and aspiration has not been well-studied. The goal of this study was to test the association between biomarker-confirmed cigarette smoking and ARDS in a diverse cohort. Design, Setting, Patients We obtained smoking histories and measured urine NNAL (a biomarker of cigarette smoke exposure) in 426 patients with ARDS risk factors (excluding trauma and transfusion) in a prospective cohort of critically ill patients at a single tertiary care center and tested the association between smoking and ARDS. Interventions None. Measurements and Main Results The association between cigarette smoke exposure and ARDS differed based on ARDS risk factor (p<0.02 for interaction). In patients with non-pulmonary sepsis as the primary ARDS risk factor (n=212), 39% of those with ARDS were current smokers by history, compared with 22% of those without ARDS (odds ratio 2.28 (95% CI 1.24–4.18); p=0.007). Likewise, cigarette smoke exposure as measured by urine NNAL was significantly associated with ARDS in this group. The increased risk of ARDS in non-pulmonary sepsis was restricted to patients with NNAL levels consistent with active smoking and was robust to adjustment for other ARDS predictors. Cigarette smoke exposure as measured by history or NNAL was not associated with ARDS in patients with other risk factors (e.g. pneumonia, aspiration). Conclusions Cigarette smoking measured both by history and by biomarker is associated with an increased risk of ARDS in patients with non-pulmonary sepsis. This finding has important implications for tobacco product regulation and for understanding the pathogenesis of ARDS. PMID:26010690

Molecular and cellular profiling of acute responses to total body radiation exposure in ovariectomized female cynomolgus macaques.

PubMed

DeBo, Ryne J; Register, Thomas C; Caudell, David L; Sempowski, Gregory D; Dugan, Gregory; Gray, Shauna; Owzar, Kouros; Jiang, Chen; Bourland, J Daniel; Chao, Nelson J; Cline, J Mark

2015-06-01

The threat of radiation exposure requires a mechanistic understanding of radiation-induced immune injury and recovery. The study objective was to evaluate responses to ionizing radiation in ovariectomized (surgically post-menopausal) female cynomolgus macaques. Animals received a single total-body irradiation (TBI) exposure at doses of 0, 2 or 5 Gy with scheduled necropsies at 5 days, 8 weeks and 24 weeks post-exposure. Blood and lymphoid tissues were evaluated for morphologic, cellular, and molecular responses. Irradiated animals developed symptoms of acute hematopoietic syndrome, and reductions in thymus weight, thymopoiesis, and bone marrow cellularity. Acute, transient increases in plasma monocyte chemoattractant protein 1 (MCP-1) were observed in 5 Gy animals along with dose-dependent alterations in messenger ribonucleic acid (mRNA) signatures in thymus, spleen, and lymph node. Expression of T cell markers was lower in thymus and spleen, while expression of macrophage marker CD68 (cluster of differentiation 68) was relatively elevated in lymphoid tissues from irradiated animals. Ovariectomized female macaques exposed to moderate doses of radiation experienced increased morbidity, including acute, dose-dependent alterations in systemic and tissue-specific biomarkers, and increased macrophage/T cell ratios. The effects on mortality exceeded expectations based on previous studies in males, warranting further investigation.

Indoor residential radon exposure and risk of childhood acute myeloid leukaemia.

PubMed

Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

1999-11-01

Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case-control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7-1.8) for 37-100 Bq m(-3) and 1.1 (95% CI 0.6-2.0) for > 100 Bq m(-3) compared with < 37 Bq m(-3). Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children > or = 2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML.

Indoor residential radon exposure and risk of childhood acute myeloid leukaemia

PubMed Central

Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

1999-01-01

Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case–control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7–1.8) for 37–100 Bq m–3 and 1.1 (95% CI 0.6–2.0) for > 100 Bq m–3 compared with < 37 Bq m–3. Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children ≥2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML. © 1999 Cancer Research Campaign PMID:10555766

Modeling Acute Health Effects of Astronauts from Exposure to Large Solar Particle Events

NASA Technical Reports Server (NTRS)

Hu, Shaowen; Kim, Myung-Hee Y.; Cucinotta, Francis A.

2011-01-01

In space exploration outside the Earth s geomagnetic field, radiation exposure from solar particle events (SPE) presents a health concern for astronauts, that could impair their performance and result in possible failure of the mission. Acute risks are of special concern during extra-vehicular activities because of the rapid onset of SPE. However, most SPEs will not lead to acute risks but can lead to mission disruption if accurate projection methods are not available. Acute Radiation Sickness (ARS) is a group of clinical syndromes developing acutely (within several seconds to 3 days) after high dose whole-body or significant partial-body ionizing radiation exposures. The manifestation of these syndromes reflects the disturbance of physiological processes of various cellular groups damaged by radiation. Hematopoietic cells, skin, epithelium, intestine, and vascular endothelium are among the most sensitive tissues of human body to ionizing radiation. Most ARS symptoms are directly related to these tissues and other systems (nervous, endocrine, and cardiovascular, etc.) with coupled regulations. Here we report the progress in bio-mathematical models to describe the dose and time-dependent early human responses to ionizing radiation. The responses include lymphocyte depression, granulocyte modulation, fatigue and weakness syndrome, and upper gastrointestinal distress. The modest dose and dose-rates of SPEs are predicted to lead to large sparing of ARS, however detailed experimental data on a range of proton dose-rates for organ doses from 0.5 to 2 Gy is needed to validate the models. We also report on the ARRBOD code that integrates the BRYNTRN and SUMDOSE codes, which are used to estimate the SPE organ doses for astronauts under various space travel scenarios, with our models of ARS. The more recent effort is to provide easy web access to space radiation risk assessment using the ARRBOD code.

Long Duration Hot Hydrogen Exposure of Nuclear Thermal Rocket Materials

NASA Technical Reports Server (NTRS)

Litchford, Ron J.; Foote, John P.; Hickman, Robert; Dobson, Chris; Clifton, Scooter

2007-01-01

An arc-heater driven hyper-thermal convective environments simulator was recently developed and commissioned for long duration hot hydrogen exposure of nuclear thermal rocket materials. This newly established non-nuclear testing capability uses a high-power, multi-gas, wall-stabilized constricted arc-heater to .produce high-temperature pressurized hydrogen flows representative of nuclear reactor core environments, excepting radiation effects, and is intended to serve as a low cost test facility for the purpose of investigating and characterizing candidate fuel/structural materials and improving associated processing/fabrication techniques. Design and engineering development efforts are fully summarized, and facility operating characteristics are reported as determined from a series of baseline performance mapping runs and long duration capability demonstration tests.

[Measures against Radiation Exposure Due to Large-Scale Nuclear Accident in Distant Place--Radioactive Materials in Nagasaki from Fukushima Daiichi Nuclear Power Plant].

PubMed

Yuan, Jun; Sera, Koichiro; Takatsuji, Toshihiro

2015-01-01

To investigate human health effects of radiation exposure due to possible future nuclear accidents in distant places and other various findings of analysis of the radioactive materials contaminating the atmosphere of Nagasaki due to the Fukushima Daiichi Nuclear Power Plant accident. The concentrations of radioactive materials in aerosols in the atmosphere of Nagasaki were measured using a germanium semiconductor detector from March 2011 to March 2013. Internal exposure dose was calculated in accordance with ICRP Publ. 72. Air trajectories were analyzed using NOAA and METEX web-based systems. (134)Cs and (137)Cs were repeatedly detected. The air trajectory analysis showed that (134)Cs and (137)Cs flew directly from the Fukushima Daiichi Nuclear Power Plant from March to April 2011. However, the direct air trajectories were rarely detected after this period even when (134)Cs and (137)Cs were detected after this period. The activity ratios ((134)Cs/(137)Cs) of almost all the samples converted to those in March 2011 were about unity. This strongly suggests that the (134)Cs and (137)Cs detected mainly originated from the Fukushima Daiichi Nuclear Power Plant accident in March 2011. Although the (134)Cs and (137)Cs concentrations per air volume were very low and the human health effects of internal exposure via inhalation is expected to be negligible, the specific activities (concentrations per aerosol mass) were relatively high. It was found that possible future nuclear accidents may cause severe radioactive contaminations, which may require radiation exposure control of farm goods to more than 1000 km from places of nuclear accidents.

Associations between chronic community noise exposure and blood pressure at rest and during acute noise and non-noise stressors among urban school children in India.

PubMed

Lepore, Stephen J; Shejwal, Bhaskar; Kim, Bang Hyun; Evans, Gary W

2010-09-01

The present study builds on prior research that has examined the association between children's chronic exposure to community noise and resting blood pressure and blood pressure dysregulation during exposure to acute stressors. A novel contribution of the study is that it examines how chronic noise exposure relates to blood pressure responses during exposure to both noise and non-noise acute stressors. The acute noise stressor was recorded street noise and the non-noise stressor was mental arithmetic. The sample consisted of 189 3rd and 6th grade children (51.9% percent boys; 52.9% 3rd graders) from a noisy (n = 95) or relatively quiet (n = 94) public school in the city of Pune, India. There were no statistically significant differences between chronic noise levels and resting blood pressure levels. However, relative to quiet-school children, noisy-school children had significantly lower increases in blood pressure when exposed to either an acute noise or non-noise stressor. This finding suggests that chronic noise exposure may result in hypo-reactivity to a variety of stressors and not just habituation to noise stressors.

Predicting adult fish acute lethality with the zebrafish embryo: relevance of test duration, endpoints, compound properties, and exposure concentration analysis.

PubMed

Knöbel, Melanie; Busser, Frans J M; Rico-Rico, Angeles; Kramer, Nynke I; Hermens, Joop L M; Hafner, Christoph; Tanneberger, Katrin; Schirmer, Kristin; Scholz, Stefan

2012-09-04

The zebrafish embryo toxicity test has been proposed as an alternative for the acute fish toxicity test, which is required by various regulations for environmental risk assessment of chemicals. We investigated the reliability of the embryo test by probing organic industrial chemicals with a wide range of physicochemical properties, toxicities, and modes of toxic action. Moreover, the relevance of using measured versus nominal (intended) exposure concentrations, inclusion of sublethal endpoints, and different exposure durations for the comparability with reported fish acute toxicity was explored. Our results confirm a very strong correlation of zebrafish embryo to fish acute toxicity. When toxicity values were calculated based on measured exposure concentrations, the slope of the type II regression line was 1 and nearly passed through the origin (1 to 1 correlation). Measured concentrations also explained several apparent outliers. Neither prolonged exposure (up to 120 h) nor consideration of sublethal effects led to a reduced number of outliers. Yet, two types of compounds were less lethal to embryos than to adult fish: a neurotoxic compound acting via sodium channels (permethrin) and a compound requiring metabolic activation (allyl alcohol).

Differences in inflammation and acute phase response but similar genotoxicity in mice following pulmonary exposure to graphene oxide and reduced graphene oxide

PubMed Central

Bengtson, Stefan; Knudsen, Kristina B.; Kyjovska, Zdenka O.; Berthing, Trine; Skaug, Vidar; Levin, Marcus; Koponen, Ismo K.; Shivayogimath, Abhay; Booth, Timothy J.; Alonso, Beatriz; Pesquera, Amaia; Zurutuza, Amaia; Thomsen, Birthe L.; Troelsen, Jesper T.; Jacobsen, Nicklas R.

2017-01-01

We investigated toxicity of 2–3 layered >1 μm sized graphene oxide (GO) and reduced graphene oxide (rGO) in mice following single intratracheal exposure with respect to pulmonary inflammation, acute phase response (biomarker for risk of cardiovascular disease) and genotoxicity. In addition, we assessed exposure levels of particulate matter emitted during production of graphene in a clean room and in a normal industrial environment using chemical vapour deposition. Toxicity was evaluated at day 1, 3, 28 and 90 days (18, 54 and 162 μg/mouse), except for GO exposed mice at day 28 and 90 where only the lowest dose was evaluated. GO induced a strong acute inflammatory response together with a pulmonary (Serum-Amyloid A, Saa3) and hepatic (Saa1) acute phase response. rGO induced less acute, but a constant and prolonged inflammation up to day 90. Lung histopathology showed particle agglomerates at day 90 without signs of fibrosis. In addition, DNA damage in BAL cells was observed across time points and doses for both GO and rGO. In conclusion, pulmonary exposure to GO and rGO induced inflammation, acute phase response and genotoxicity but no fibrosis. PMID:28570647

Abundance of Plasma Antioxidant Proteins Confers Tolerance to Acute Hypobaric Hypoxia Exposure

PubMed Central

Padhy, Gayatri; Sethy, Niroj Kumar; Ganju, Lilly

2013-01-01

Abstract Padhy, Gayatri, Niroj Kumar Sethy, Lilly Ganju, and Kalpana Bhargava. Abundance of plasma antioxidant proteins confers tolerance to acute hypobaric hypoxia exposure. High Alt Med Biol 14:289–297, 2013—Systematic identification of molecular signatures for hypobaric hypoxia can aid in better understanding of human adaptation to high altitude. In an attempt to identify proteins promoting hypoxia tolerance during acute exposure to high altitude, we screened and identified hypoxia tolerant and susceptible rats based on hyperventilation time to a simulated altitude of 32,000 ft (9754 m). The hypoxia tolerance was further validated by estimating 8-isoprotane levels and protein carbonyls, which revealed that hypoxia tolerant rats possessed significant lower plasma levels as compared to susceptible rats. We used a comparative plasma proteome profiling approach using 2-dimensional gel electrophoresis (2-DGE) combined with MALDI TOF/TOF for both groups, along with an hypoxic control group. This resulted in the identification of 19 differentially expressed proteins. Seven proteins (TTR, GPx-3, PON1, Rab-3D, CLC11, CRP, and Hp) were upregulated in hypoxia tolerant rats, while apolipoprotein A-I (APOA1) was upregulated in hypoxia susceptible rats. We further confirmed the consistent higher expression levels of three antioxidant proteins (PON1, TTR, and GPx-3) in hypoxia-tolerant animals using ELISA and immunoblotting. Collectively, these proteomics-based results highlight the role of antioxidant enzymes in conferring hypoxia tolerance during acute hypobaric hypoxia. The expression of these antioxidant enzymes could be used as putative biomarkers for screening altitude adaptation as well as aiding in better management of altered oxygen pathophysiologies. PMID:24067188

Stress hormonal changes in the brain and plasma after acute noise exposure in mice.

PubMed

Jin, Sang Gyun; Kim, Min Jung; Park, So Young; Park, Shi Nae

2017-06-01

To investigate the effects of acute noise stress on two amine stress hormones, norepinephrine (NE) and 5-hydroxyindoleacetic acid (5-HIAA) in the brain and plasma of mice after noise exposure. Mice were grouped into the control and noise groups. Mice in the noise group were exposed to white noise of 110dB sound pressure level for 60min. Auditory brainstem response thresholds, distortion product otoacoustic emissions, the organ of Corti grading scores, western blots of NE/5-HIAA in the whole brain and hippocampus, and the plasma levels of NE/5-HIAA were compared between the two groups. Significant hearing loss and cochlear damage were demonstrated in the noise group. NE and 5-HIAA in the hippocampus were elevated in the noise group (p=0.019/0.022 for NE/5-HIAA vs. the control). Plasma levels of NE and 5-HIAA were not statistically different between the groups (p=0.052/0.671 for NE/5-HIAA). Hearing loss with outer hair cell dysfunction and morphological changes of the organ of Corti after noise exposure in C57BL/6 mice proved the reliability of our animal model as an acute noise stress model. NE and 5-HIAA are suggested to be the potential biomarkers for acute noise stress in the hippocampus. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC

EPA Science Inventory

CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC. UP Kodavanti, MC Schladweiler, AD Ledbetter, RH Jaskot, PS Gilmour, DC Christiani, WP Watkinson, DL Costa, JK McGee, A Nyska. NHEERL, USEPA, RTP, NC; CEMALB, UNC, Chapel Hil...

Acute stress exposure preceding transient global brain ischemia exacerbates the decrease in cortical remodeling potential in the rat retrosplenial cortex.

PubMed

Kutsuna, Nobuo; Yamashita, Akiko; Eriguchi, Takashi; Oshima, Hideki; Suma, Takeshi; Sakatani, Kaoru; Yamamoto, Takamitsu; Yoshino, Atsuo; Katayama, Yoichi

2014-01-01

Doublecortin (DCX)-immunoreactive (-ir) cells are candidates that play key roles in adult cortical remodeling. We have previously reported that DCX-ir cells decrease after stress exposure or global brain ischemia (GBI) in the cingulate cortex (Cg) of rats. Herein, we investigate whether the decrease in DCX-ir cells is exacerbated after GBI due to acute stress exposure preconditioning. Twenty rats were divided into 3 groups: acute stress exposure before GBI (Group P), non-stress exposure before GBI (Group G), and controls (Group C). Acute stress or GBI was induced by a forced swim paradigm or by transient bilateral common carotid artery occlusion, respectively. DCX-ir cells were investigated in the anterior cingulate cortex (ACC) and retrosplenial cortex (RS). The number of DCX-ir cells per unit area (mm(2)) decreased after GBI with or without stress preconditioning in the ACC and in the RS (ANOVA followed by a Tukey-type test, P<0.001). Moreover, compared to Group G, the number in Group P decreased significantly in RS (P<0.05), though not significantly in ACC. Many of the DCX-ir cells were co-localized with the GABAergic neuronal marker parvalbumin. The present study indicates that cortical remodeling potential of GABAergic neurons of Cg decreases after GBI, and moreover, the ratio of the decrease is exacerbated by acute stress preconditioning in the RS. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Chronic marijuana smoke exposure in the rhesus monkey. IV: Neurochemical effects and comparison to acute and chronic exposure to delta-9-tetrahydrocannabinol (THC) in rats.

PubMed

Ali, S F; Newport, G D; Scallet, A C; Paule, M G; Bailey, J R; Slikker, W

1991-11-01

THC is the major psychoactive constituent of marijuana and is known to produce psychopharmacological effects in humans. These studies were designed to determine whether acute or chronic exposure to marijuana smoke or THC produces in vitro or in vivo neurochemical alterations in rat or monkey brain. For the in vitro study, THC was added (1-100 nM) to membranes prepared from different regions of the rat brain and muscarinic cholinergic (MCh) receptor binding was measured. For the acute in vivo study, rats were injected IP with vehicle, 1, 3, 10, or 30 mg THC/kg and sacrificed 2 h later. For the chronic study, rats were gavaged with vehicle or 10 or 20 mg THC/kg daily, 5 days/week for 90 days and sacrificed either 24 h or 2 months later. Rhesus monkeys were exposed to the smoke of a single 2.6% THC cigarette once a day, 2 or 7 days a week for 1 year. Approximately 7 months after the last exposure, animals were sacrificed by overdose with pentobarbital for neurochemical analyses. In vitro exposure to THC produced a dose-dependent inhibition of MCh receptor binding in several brain areas. This inhibition of MCh receptor binding, however, was also observed with two other nonpsychoactive derivatives of marijuana, cannabidiol and cannabinol. In the rat in vivo study, we found no significant changes in MCh or other neurotransmitter receptor binding in hippocampus, frontal cortex or caudate nucleus after acute or chronic exposure to THC. In the monkey brain, we found no alterations in the concentration of neurotransmitters in caudate nucleus, frontal cortex, hypothalamus or brain stem.(ABSTRACT TRUNCATED AT 250 WORDS)

Exposure to traffic pollution, acute inflammation and autonomic response in a panel of car commuters.

PubMed

Sarnat, Jeremy A; Golan, Rachel; Greenwald, Roby; Raysoni, Amit U; Kewada, Priya; Winquist, Andrea; Sarnat, Stefanie E; Dana Flanders, W; Mirabelli, Maria C; Zora, Jennifer E; Bergin, Michael H; Yip, Fuyuen

2014-08-01

Exposure to traffic pollution has been linked to numerous adverse health endpoints. Despite this, limited data examining traffic exposures during realistic commutes and acute response exists. We conducted the Atlanta Commuters Exposures (ACE-1) Study, an extensive panel-based exposure and health study, to measure chemically-resolved in-vehicle exposures and corresponding changes in acute oxidative stress, lipid peroxidation, pulmonary and systemic inflammation and autonomic response. We recruited 42 adults (21 with and 21 without asthma) to conduct two 2-h scripted highway commutes during morning rush hour in the metropolitan Atlanta area. A suite of in-vehicle particulate components were measured in the subjects' private vehicles. Biomarker measurements were conducted before, during, and immediately after the commutes and in 3 hourly intervals after commutes. At measurement time points within 3h after the commute, we observed mild to pronounced elevations relative to baseline in exhaled nitric oxide, C-reactive-protein, and exhaled malondialdehyde, indicative of pulmonary and systemic inflammation and oxidative stress initiation, as well as decreases relative to baseline levels in the time-domain heart-rate variability parameters, SDNN and rMSSD, indicative of autonomic dysfunction. We did not observe any detectable changes in lung function measurements (FEV1, FVC), the frequency-domain heart-rate variability parameter or other systemic biomarkers of vascular injury. Water soluble organic carbon was associated with changes in eNO at all post-commute time-points (p<0.0001). Our results point to measureable changes in pulmonary and autonomic biomarkers following a scripted 2-h highway commute. Copyright © 2014 Elsevier Inc. All rights reserved.

Exposure to traffic pollution, acute inflammation and autonomic response in a panel of car commuters

PubMed Central

Sarnat, Jeremy A.; Golan, Rachel; Greenwald, Roby; Raysoni, Amit U.; Kewada, Priya; Winquist, Andrea; Sarnat, Stefanie E.; Flanders, W. Dana; Mirabelli, Maria C.; Zora, Jennifer E.; Bergin, Michael H.; Yip, Fuyuen

2015-01-01

Background Exposure to traffic pollution has been linked to numerous adverse health endpoints. Despite this, limited data examining traffic exposures during realistic commutes and acute response exists. Objectives: We conducted the Atlanta Commuters Exposures (ACE-1) Study, an extensive panel-based exposure and health study, to measure chemically-resolved in-vehicle exposures and corresponding changes in acute oxidative stress, lipid peroxidation, pulmonary and systemic inflammation and autonomic response. Methods We recruited 42 adults (21 with and 21 without asthma) to conduct two 2-h scripted highway commutes during morning rush hour in the metropolitan Atlanta area. A suite of in-vehicle particulate components were measured in the subjects’ private vehicles. Biomarker measurements were conducted before, during, and immediately after the commutes and in 3 hourly intervals after commutes. Results At measurement time points within 3 h after the commute, we observed mild to pronounced elevations relative to baseline in exhaled nitric oxide, C-reactive-protein, and exhaled malondialdehyde, indicative of pulmonary and systemic inflammation and oxidative stress initiation, as well as decreases relative to baseline levels in the time-domain heart-rate variability parameters, SDNN and rMSSD, indicative of autonomic dysfunction. We did not observe any detectable changes in lung function measurements (FEV1, FVC), the frequency-domain heart-rate variability parameter or other systemic biomarkers of vascular injury. Water soluble organic carbon was associated with changes in eNO at all post-commute time-points (p < 0.0001). Conclusions Our results point to measureable changes in pulmonary and autonomic biomarkers following a scripted 2-h highway commute. PMID:24906070

Acute respiratory toxicity following inhalation exposure to soman in guinea pigs.

PubMed

Perkins, Michael W; Pierre, Zdenka; Rezk, Peter; Sabnekar, Praveena; Kabra, Kareem; Chanda, Soma; Oguntayo, Samuel; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2010-06-01

Respiratory toxicity and lung injury following inhalation exposure to chemical warfare nerve agent soman was examined in guinea pigs without therapeutics to improve survival. A microinstillation inhalation exposure technique that aerosolizes the agent in the trachea was used to administer soman to anesthetized age and weight matched male guinea pigs. Animals were exposed to 280, 561, 841, and 1121 mg/m(3) concentrations of soman for 4 min. Survival data showed that all saline controls and animals exposed to 280 and 561 mg/m(3) soman survived, while animals exposed to 841, and 1121 mg/m(3) resulted in 38% and 13% survival, respectively. The microinstillation inhalation exposure LCt(50) for soman determined by probit analysis was 827.2mg/m(3). A majority of the animals that died at 1121 mg/m(3) developed seizures and died within 15-30 min post-exposure. There was a dose-dependent decrease in pulse rate and blood oxygen saturation of animals exposed to soman at 5-6.5 min post-exposure. Body weight loss increased with the dose of soman exposure. Bronchoalveolar lavage (BAL) fluid and blood acetylcholinesterase and butyrylcholinesterase activity was inhibited dose-dependently in soman treated groups at 24h. BAL cells showed a dose-dependent increase in cell death and total cell counts following soman exposure. Edema by wet/dry weight ratio of the accessory lung lobe and trachea was increased slightly in soman exposed animals. An increase in total bronchoalveolar lavage fluid protein was observed in soman exposed animals at all doses. Differential cell counts of BAL and blood showed an increase in total lymphocyte counts and percentage of neutrophils. These results indicate that microinstillation inhalation exposure to soman causes respiratory toxicity and acute lung injury in guinea pigs. (c) 2010 Elsevier Inc. All rights reserved.

DISTRIBUTION OF 14C-ATRAZINE FOLLOWING AN ACUTE LACTATIONAL EXPOSURE IN THE WISTAR RAT.

EPA Science Inventory

The purpose of the present study was to examine the distribution of atrazine in the lactating dam and suckling neonate following an acute exposure to either 2 or 4 mg/kg 14C-atrazine (14C-ATR) by gavage. 14C-ATR was administered to the nursing dam on postnatal day 3 by oral gavag...

Effects of acute and chronic exposure to both 900 MHz and 2100 MHz electromagnetic radiation on glutamate receptor signaling pathway.

PubMed

Gökçek-Saraç, Çiğdem; Er, Hakan; Kencebay Manas, Ceren; Kantar Gok, Deniz; Özen, Şükrü; Derin, Narin

2017-09-01

To demonstrate the molecular effects of acute and chronic exposure to both 900 and 2100 MHz radiofrequency electromagnetic radiation (RF-EMR) on the hippocampal level/activity of some of the enzymes - including PKA, CaMKIIα, CREB, and p44/42 MAPK - from N-methyl-D-aspartate receptor (NMDAR)-related signaling pathways. Rats were divided into the following groups: sham rats, and rats exposed to 900 and 2100 MHz RF-EMR for 2 h/day for acute (1 week) or chronic (10 weeks), respectively. Western blotting and activity measurement assays were used to assess the level/activity of the selected enzymes. The obtained results revealed that the hippocampal level/activity of selected enzymes was significantly higher in the chronic groups as compared to the acute groups at both 900 and 2100 MHz RF-EMR exposure. In addition, hippocampal level/activity of selected enzymes was significantly higher at 2100 MHz RF-EMR than 900 MHz RF-EMR in both acute and chronic groups. The present study provides experimental evidence that both exposure duration (1 week versus 10 weeks) and different carrier frequencies (900 vs. 2100 MHz) had different effects on the protein expression of hippocampus in Wistar rats, which might encourage further research on protection against RF-EMR exposure.

Acute Changes in Heart Rate Variability in Subjects With Diabetes Following a Highway Traffic Exposure

PubMed Central

Laumbach, Robert J.; Rich, David Q.; Gandhi, Sampada; Amorosa, Louis; Schneider, Stephen; Zhang, Junfeng; Ohman-Strickland, Pamela; Gong, Jicheng; Lelyanov, Oleksiy; Kipen, Howard M.

2014-01-01

Objective To pilot a protocol to evaluate acute cardiovascular effects in in-vehicle exposure to traffic air pollutants in people with diabetes. Methods Twenty-one volunteers with type 2 diabetes were passengers on 90- to 110-minute car rides on a busy highway. We measured in-vehicle particle number and mass (PM2.5) nitrogen dioxide, and carbon monoxide and heart rate, heart rate variability (HRV), and blood pressure. Results Compared with pre-ride measurements, we found a decrease in high frequency (HF) HRV from pre-ride to next day (ratio 0.66, 95% CI = 0.47 to 0.93) and an increase in low frequency to HF ratio at post-ride (ratio 1.92, 95% CI = 1.21 to 3.05) at post-ride. Interquartile range increases in measured pollutants were associated with next-day decreases in HR HRV. Conclusions This protocol appears useful for assessing acute adverse cardiovascular effects of in-vehicle exposures among people who have diabetes. PMID:20190650

Acute invasive pulmonary aspergillosis, shortly after occupational exposure to polluted muddy water, in a previously healthy subject

PubMed Central

Pilaniya, Vikas; Gera, Kamal; Gothi, Rajesh; Shah, Ashok

2015-01-01

Invasive pulmonary aspergillosis (IPA) predominantly occurs in severely neutropenic immunocompromised subjects. The occurrence of acute IPA after brief but massive exposure to Aspergillus conidia in previously healthy subjects has been documented, although only six such cases have been reported. The diagnosis was delayed in all six of the affected patients, five of whom died. We report the case of a 50-year-old HIV-negative male, a water pipeline maintenance worker, who presented with acute-onset dyspnea and fever one day after working for 2 h in a deep pit containing polluted, muddy water. Over a one-month period, his general condition deteriorated markedly, despite antibiotic therapy. Imaging showed bilateral diffuse nodules with cavitation, some of which were surrounded by ground-glass opacity suggestive of a halo sign (a hallmark of IPA). Cultures (of sputum/bronchial aspirate samples) and serology were positive for Aspergillus fumigatus. After being started on itraconazole, the patient improved. We conclude that massive exposure to Aspergillus conidia can lead to acute IPA in immunocompetent subjects. PMID:26578140

Studies of young female responses to acute ozone exposure. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, W.C.

The primary purposes of this research were to determine if: (1) young adult females respond with greater acute effects of ozone (O3) than their male counterparts at a dose relative to lung size as well as at the same total dose; (2) O3 response in females is influenced by the disparate levels of progesterone (a steroid hormone) that they experience during the various phases of their menstrual cycles; and (3) O3 exposure has an effect on the integrity of normal menstrual cycles of healthy young adult females.

Bittersweet: Real-Time, Dynamic Changes in Blood Glucose Levels during an Acute Ozone Exposure in Rats

EPA Science Inventory

In humans and rats, acute exposures to ozone have been shown to activate the sympathetic-adrenal-medullary and hypothalamic-pituitary-adrenal axes to induce multi-organ metabolic alterations including impaired glucose homeostasis. These findings have largely been gleaned from on...

Immune status influences fear and anxiety responses in mice after acute stress exposure

PubMed Central

Clark, Sarah M.; Sand, Joseph; Francis, T. Chase; Nagaraju, Anitha; Michael, Kerry C.; Keegan, Achsah D.; Kusnecov, Alexander; Gould, Todd D.; Tonelli, Leonardo H.

2014-01-01

Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2−/− mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2−/− mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2−/− mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect

Acute posttraumatic stress symptoms and depression after exposure to the 2005 Saskatchewan Centennial Air Show disaster: prevalence and predictors.

PubMed

Taylor, Steven; Asmundson, Gordon J G; Carleton, R Nicholas; Brundin, Peter

2007-01-01

The purpose of this study was to determine the prevalence of acute distress-that is, clinically significant posttraumatic stress symptoms (PTSS) and depression-and to identify predictors of each in a sample of people who witnessed a fatal aircraft collision at the 2005 Saskatchewan Centennial Air Show. Air Show attendees (N = 157) were recruited by advertisements in the local media and completed an Internet-administered battery of questionnaires. Based on previously established cut-offs, 22 percent respondents had clinically significant PTSS and 24 percent had clinically significant depressive symptoms. Clinically significant symptoms were associated with posttrauma impairment in social and occupational functioning. Acute distress was associated with several variables, including aspects of Air Show trauma exposure, severity of prior trauma exposure, low posttrauma social support (ie, negative responses by others), indices of poor coping (eg, intolerance of uncertainty, rumination about the trauma), and elevated scores on anxiety sensitivity, the personality trait of absorption, and dissociative tendencies. Results suggest that clinically significant acute distress is common in the aftermath of witnessed trauma. The statistical predictors (correlates) of acute distress were generally consistent with the results of studies of other forms of trauma. People with elevated scores on theoretical vulnerability factors (eg, elevated anxiety sensitivity) were particularly likely to develop acute distress.

EFFECT OF AN ACUTE EXPOSURE TO MOLINATE ON OVULATION IN THE LONG-EVANS HOODED RAT

EPA Science Inventory

EFFECT OF AN ACUTE EXPOSURE TO MOLINATE ON OVULATION IN THE LONG-EVANS HOODED RAT. T E Stoker, D L Guidici, S C Jeffay, W K McElroy, S D Perreault and R L Cooper. Reproductive Toxicology Division, NHEERL, ORD, US EPA, RTP, NC. Sponsor: RJ Kavlock.
Molinate, a thiocarbamate ...

Guidelines for exposure assessment in health risk studies following a nuclear reactor accident.

PubMed

Bouville, André; Linet, Martha S; Hatch, Maureen; Mabuchi, Kiyohiko; Simon, Steven L

2014-01-01

Worldwide concerns regarding health effects after the Chernobyl and Fukushima nuclear power plant accidents indicate a clear need to identify short- and long-term health impacts that might result from accidents in the future. Fundamental to addressing this problem are reliable and accurate radiation dose estimates for the affected populations. The available guidance for activities following nuclear accidents is limited with regard to strategies for dose assessment in health risk studies. Here we propose a comprehensive systematic approach to estimating radiation doses for the evaluation of health risks resulting from a nuclear power plant accident, reflected in a set of seven guidelines. Four major nuclear reactor accidents have occurred during the history of nuclear power production. The circumstances leading to these accidents were varied, as were the magnitude of the releases of radioactive materials, the pathways by which persons were exposed, the data collected afterward, and the lifestyle factors and dietary consumption that played an important role in the associated radiation exposure of the affected populations. Accidents involving nuclear reactors may occur in the future under a variety of conditions. The guidelines we recommend here are intended to facilitate obtaining reliable dose estimations for a range of different exposure conditions. We recognize that full implementation of the proposed approach may not always be feasible because of other priorities during the nuclear accident emergency and because of limited resources in manpower and equipment. The proposed approach can serve as a basis to optimize the value of radiation dose reconstruction following a nuclear reactor accident.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture.

PubMed

Yang, Minqi; Ma, Ning; Zhu, Yingying; Su, Ying-Chu; Chen, Qingwei; Hsiao, Fan-Chi; Ji, Yanran; Yang, Chien-Ming; Zhou, Guofu

2018-03-15

Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

Prediction of Susceptibility to Acute Mountain Sickness Using Hypoxia-Induced Intrapulmonary Arteriovenous Shunt and Intracardiac Shunt Fractions

DTIC Science & Technology

2013-10-01

echocardiography to determine bubble/shunt scores. We will also use nuclear medicine imaging to determine shunt fractions following acute exposures to... echocardiography while breathing hypoxic gas mixtures. – TASK COMPLETED. For Task #1.3 “Quantify shunt during hypoxic exposure with SPECT CT – PFO...subjects.” 19 PFO+ subjects have completed saline contrast echocardiography while breathing hypoxic gas mixtures for 30 min. One PFO+ subject that had

Virtual reality jogging as a novel exposure paradigm for the acute urge to be physically active in patients with eating disorders: Implications for treatment.

PubMed

Paslakis, Georgios; Fauck, Vanessa; Röder, Kathrin; Rauh, Elisabeth; Rauh, Manfred; Erim, Yesim

2017-11-01

The acute urge to be physically active is a relevant clinical phenomenon in patients suffering from eating disorders. In this study with n = 20 female patients with anorexia nervosa and n = 10 female patients with bulimia nervosa, a virtual reality (VR) jogging paradigm was applied as a novel highly immersive 3D exposure paradigm. Patients were asked to rate their acute urge to be physically active during the exposure procedure. A 10-item self-report questionnaire (smQ) was developed to capture the cognitive, emotional, and behavioral aspects of the acute urge to move. We hypothesized that exposure would lead to habituation of the urge to be physically active. We also hypothesized that leptin levels would be associated with the degree of the subjective urge to be physically active, while habituation would be associated with a decrease in stress hormones (α-amylase, cortisol, and cortisone in saliva). A statistically significant change in subjective scores in the smQ from baseline to postexposure was seen. Our novel VR paradigm may serve as a therapeutic tool for exposure and habituation of the urge of acutely engaging in physical activity in patients with eating disorders. © 2017 Wiley Periodicals, Inc.

A retrospective study on acute health effects due to volcanic ash exposure during the eruption of Mount Etna (Sicily) in 2002

PubMed Central

2013-01-01

Background Mount Etna, located in the eastern part of Sicily (Italy), is the highest and most active volcano in Europe. During the sustained eruption that occurred in October-November 2002 huge amounts of volcanic ash fell on a densely populated area south-east of Mount Etna in Catania province. The volcanic ash fall caused extensive damage to infrastructure utilities and distress in the exposed population. This retrospective study evaluates whether or not there was an association between ash fall and acute health effects in exposed local communities. Methods We collected the number and type of visits to the emergency department (ED) for diseases that could be related to volcanic ash exposure in public hospitals of the Province of Catania between October 20 and November 7, 2002. We compared the magnitude of differences in ED visits between the ash exposure period in 2002 and the same period of the previous year 2001. Results We observed a significant increase of ED visits for acute respiratory and cardiovascular diseases, and ocular disturbances during the ash exposure time period. Conclusions There was a positive association between exposure to volcanic ash from the 2002 eruption of Mount Etna and acute health effects in the Catania residents. This study documents the need for public health preparedness and response initiatives to protect nearby populations from exposure to ash fall from future eruptions of Mount Etna. PMID:23924394

A retrospective study on acute health effects due to volcanic ash exposure during the eruption of Mount Etna (Sicily) in 2002.

PubMed

Lombardo, Daniele; Ciancio, Nicola; Campisi, Raffaele; Di Maria, Annalisa; Bivona, Laura; Poletti, Venerino; Mistretta, Antonio; Biggeri, Annibale; Di Maria, Giuseppe

2013-08-07

Mount Etna, located in the eastern part of Sicily (Italy), is the highest and most active volcano in Europe. During the sustained eruption that occurred in October-November 2002 huge amounts of volcanic ash fell on a densely populated area south-east of Mount Etna in Catania province. The volcanic ash fall caused extensive damage to infrastructure utilities and distress in the exposed population. This retrospective study evaluates whether or not there was an association between ash fall and acute health effects in exposed local communities. We collected the number and type of visits to the emergency department (ED) for diseases that could be related to volcanic ash exposure in public hospitals of the Province of Catania between October 20 and November 7, 2002. We compared the magnitude of differences in ED visits between the ash exposure period in 2002 and the same period of the previous year 2001. We observed a significant increase of ED visits for acute respiratory and cardiovascular diseases, and ocular disturbances during the ash exposure time period. There was a positive association between exposure to volcanic ash from the 2002 eruption of Mount Etna and acute health effects in the Catania residents. This study documents the need for public health preparedness and response initiatives to protect nearby populations from exposure to ash fall from future eruptions of Mount Etna.

Flight Performance During Exposure to Acute Hypobaric Hypoxia.

PubMed

Steinman, Yuval; van den Oord, Marieke H A H; Frings-Dresen, Monique H W; Sluiter, Judith K

2017-08-01

The purpose of the present study was to examine the influence of hypobaric hypoxia (HH) on a pilot's flight performance during exposure to simulated altitudes of 91, 3048, and 4572 m (300, 10,000, and 15,000 ft) and to monitor the pilot's physiological reactions. In a single-blinded counter-balanced design, 12 male pilots were exposed to HH while flying in a flight simulator that had been placed in a hypobaric chamber. Flight performance of the pilots, pilot's alertness level, Spo2, heart rate (HR), minute ventilation (VE), and breathing frequency (BF) were measured. A significant difference was found in Flight Profile Accuracy (FPA) between the three altitudes. Post hoc analysis showed no significant difference in performance between 91 m and 3048 m. A trend was observed at 4572 m, suggesting a decrease in flight performance at that altitude. Significantly lower alertness levels were observed at the start of the flight at 4572 m compared to 91 m, and at the end of the flight at 4572 m compared to the start at that altitude. Spo2 and BF decreased, and HR increased significantly with altitude. The present study did not provide decisive evidence for a decrease in flight performance during exposure to simulated altitudes of 3048 and 4572 m. However, large interindividual variation in pilots' flight performance combined with a gradual decrease in alertness levels observed in the present study puts into question the ability of pilots to safely fly an aircraft while exposed to these altitudes without supplemental oxygen.Steinman Y, van den Oord MHAH, Frings-Dresen MHW, Sluiter JK. Flight performance during exposure to acute hypobaric hypoxia. Aerosp Med Hum Perform. 2017; 88(8):760-767.

Acute lion's mane jellyfish, Cyanea capillata (Cnideria: Scyphozoa), exposure to Atlantic salmon (Salmo salar L.).

PubMed

Powell, M D; Åtland, Å; Dale, T

2018-05-01

Jellyfish-induced gill pathology relies upon occasional diagnostic observations yet the extent and impact of jellyfish blooms on aquaculture may be significant. Idiopathic gill lesions are often observed in apparently healthy fish. This study exposed Atlantic salmon (Salmo salar L.) smolts to macerated Cyanea capillata at 2.5 and 5 g/L for 2 hr under controlled laboratory conditions. Blood chemistry and gill histopathology were examined over a subsequent 4-week period. Fish showed an acute response to the presence of jellyfish, including characteristic external "whiplash" discoloration of the skin and acute increases in blood electrolytes and CO 2 concentration; however, these were resolved within 4 days after exposure. Histopathologically, gills showed first an acute oedema with epithelial separation followed by focal haemorrhage and thrombus formation, and then progressive inflammatory epithelial hyperplasia that progressively resolved over the 4 weeks post-exposure. Results were consistent with the envenomation of gills with cytotoxic neurotoxins and haemolysins known to be produced by C. capillata. This study suggests that many focal hyperplastic lesions on gills, especially those involving focal thrombi, may be the result of jellyfish stings. Thus, the presence of jellyfish and their impact may be severe and understated in terms of marine fish aquaculture and fish welfare. © 2018 John Wiley & Sons Ltd.

Effects of acute hypoxic exposure on oxygen affinity of human red blood cells.

PubMed

Chowdhury, Aniket; Dasgupta, Raktim

2017-01-20

Adaptation of red blood cells subjected to acute hypoxia, crucial for managing high altitude syndrome and pulmonary diseases, has been investigated. For this, red blood cells were exposed to the acute hypoxic condition by purging nitrogen over increasing time periods from 15 to 60 min and thereafter equilibrated with atmospheric oxygen for 10 min. Raman spectra of these red blood cells were then recorded and analyzed to look for changes in the level of oxygenation compared to unexposed cells. A decreasing oxygen affinity for the cells was observed with increasing time of exposure to the hypoxic condition. This change in oxygen affinity for the red blood cells may result from metabolic adjustment of the cells under the hypoxic condition to promote increased concentration of intracellular 2, 3-diphosphoglycerate.

Acute radiation enteritis caused by dose-dependent radiation exposure in dogs: experimental research.

PubMed

Xu, Wenda; Chen, Jiang; Xu, Liu; Li, Hongyu; Guo, Xiaozhong

2014-12-01

Accidental or intended radiation exposure in mass casualty settings presents a serious and on-going threat. The development of mitigating and treating agents requires appropriate animal models. Unfortunately, the majority of research on radiation enteritis in animals has lacked specific assessments and targeted therapy. Our study showed beagle dogs, treated by intensity-modulated radiation therapy (IMRT) for abdominal irradiation, were administered single X-ray doses of 8-30 Gy. The degree of intestinal tract injury for all of the animals after radiation exposure was evaluated with regard to clinical syndrome, endoscopic findings, histological features, and intestinal function. The range of single doses (8 Gy, 10-14 Gy, and 16-30 Gy) represented the degree of injury (mild, moderate, and severe, respectively). Acute radiation enteritis included clinical syndrome with fever, vomiting, diarrhea, hemafecia, and weight loss; typical endoscopic findings included edema, bleeding, mucosal abrasions, and ulcers; and intestinal biopsy results revealed mucosal necrosis, erosion, and loss, inflammatory cell infiltration, hemorrhage, and congestion. Changes in serum diamine oxides (DAOs) and d-xylose represented intestinal barrier function and absorption function, respectively, and correlated with the extent of damage (P < 0.05 and P < 0.05, respectively). We successfully developed a dog model of acute radiation enteritis, thus obtaining a relatively objective evaluation of intestinal tract injury based on clinical performance and laboratory examination. The method of assessment of the degree of intestinal tract injury after abdominal irradiation could be beneficial in the development of novel and effective therapeutic strategies for acute radiation enteritis. © 2014 by the Society for Experimental Biology and Medicine.

Mental- and physical-health effects of acute exposure to media images of the September 11, 2001, attacks and the Iraq War.

PubMed

Silver, Roxane Cohen; Holman, E Alison; Andersen, Judith Pizarro; Poulin, Michael; McIntosh, Daniel N; Gil-Rivas, Virginia

2013-09-01

Millions of people witnessed early, repeated television coverage of the September 11 (9/11), 2001, terrorist attacks and were subsequently exposed to graphic media images of the Iraq War. In the present study, we examined psychological- and physical-health impacts of exposure to these collective traumas. A U.S. national sample (N = 2,189) completed Web-based surveys 1 to 3 weeks after 9/11; a subsample (n = 1,322) also completed surveys at the initiation of the Iraq War. These surveys measured media exposure and acute stress responses. Posttraumatic stress symptoms related to 9/11 and physician-diagnosed health ailments were assessed annually for 3 years. Early 9/11- and Iraq War-related television exposure and frequency of exposure to war images predicted increased posttraumatic stress symptoms 2 to 3 years after 9/11. Exposure to 4 or more hr daily of early 9/11-related television and cumulative acute stress predicted increased incidence of health ailments 2 to 3 years later. These findings suggest that exposure to graphic media images may result in physical and psychological effects previously assumed to require direct trauma exposure.

Consumption of fruits and vegetables and probabilistic assessment of the cumulative acute exposure to organophosphorus and carbamate pesticides of schoolchildren in Slovenia.

PubMed

Blaznik, Urška; Yngve, Agneta; Eržen, Ivan; Hlastan Ribič, Cirila

2016-02-01

Adequate consumption of fruits and vegetables is a part of recommendations for a healthy diet. The aim of the present study was to assess acute cumulative dietary exposure to organophosphorus and carbamate pesticides via fruit and vegetable consumption by the population of schoolchildren aged 11-12 years and the level of risk for their health. Cumulative probabilistic risk assessment methodology with the index compound approach was applied. Slovenia, primary schools. Schoolchildren (n 1145) from thirty-one primary schools in Slovenia. Children were part of the PRO GREENS study 2009/10 which assessed 11-year-olds' consumption of fruit and vegetables in ten European countries. The cumulative acute exposure amounted to 8.3 (95% CI 7.7, 10.6) % of the acute reference dose (ARfD) for acephate as index compound (100 µg/kg body weight per d) at the 99.9th percentile for daily intake and to 4.5 (95% CI 3.5, 4.7) % of the ARfD at the 99.9th percentile for intakes during school time and at lunch. Apples, bananas, oranges and lettuce contributed most to the total acute pesticides intake. The estimations showed that acute dietary exposure to organophosphorus and carbamate pesticides is not a health concern for schoolchildren with the assessed dietary patterns of fruit and vegetable consumption.

Vitamin K3 attenuates lipopolysaccharide-induced acute lung injury through inhibition of nuclear factor-κB activation

PubMed Central

Tanaka, S; Nishiumi, S; Nishida, M; Mizushina, Y; Kobayashi, K; Masuda, A; Fujita, T; Morita, Y; Mizuno, S; Kutsumi, H; Azuma, T; Yoshida, M

2010-01-01

Vitamin K is a family of fat-soluble compounds including phylloquinone (vitamin K1), menaquinone (vitamin K2) and menadione (vitamin K3). Recently, it was reported that vitamin K, especially vitamins K1 and K2, exerts a variety of biological effects, and these compounds are expected to be candidates for therapeutic agents against various diseases. In this study, we investigated the anti-inflammatory effects of vitamin K3 in in vitro cultured cell experiments and in vivo animal experiments. In human embryonic kidney (HEK)293 cells, vitamin K3 inhibited the tumour necrosis factor (TNF)-α-evoked translocation of nuclear factor (NF)-κB into the nucleus, although vitamins K1 and K2 did not. Vitamin K3 also suppressed the lipopolysaccharide (LPS)-induced nuclear translocation of NF-κB and production of TNF-α in mouse macrophage RAW264·7 cells. Moreover, the addition of vitamin K3 before and after LPS administration attenuated the severity of lung injury in an animal model of acute lung injury/acute respiratory distress syndrome (ARDS), which occurs in the setting of acute severe illness complicated by systemic inflammation. In the ARDS model, vitamin K3 also suppressed the LPS-induced increase in the serum TNF-α level and inhibited the LPS-evoked nuclear translocation of NF-κB in lung tissue. Despite marked efforts, little therapeutic progress has been made, and the mortality rate of ARDS remains high. Vitamin K3 may be an effective therapeutic strategy against acute lung injury including ARDS. PMID:20030669

Vitamin K3 attenuates lipopolysaccharide-induced acute lung injury through inhibition of nuclear factor-kappaB activation.

PubMed

Tanaka, S; Nishiumi, S; Nishida, M; Mizushina, Y; Kobayashi, K; Masuda, A; Fujita, T; Morita, Y; Mizuno, S; Kutsumi, H; Azuma, T; Yoshida, M

2010-05-01

Vitamin K is a family of fat-soluble compounds including phylloquinone (vitamin K1), menaquinone (vitamin K2) and menadione (vitamin K3). Recently, it was reported that vitamin K, especially vitamins K1 and K2, exerts a variety of biological effects, and these compounds are expected to be candidates for therapeutic agents against various diseases. In this study, we investigated the anti-inflammatory effects of vitamin K3 in in vitro cultured cell experiments and in vivo animal experiments. In human embryonic kidney (HEK)293 cells, vitamin K3 inhibited the tumour necrosis factor (TNF)-alpha-evoked translocation of nuclear factor (NF)-kappaB into the nucleus, although vitamins K1 and K2 did not. Vitamin K3 also suppressed the lipopolysaccharide (LPS)-induced nuclear translocation of NF-kappaB and production of TNF-alpha in mouse macrophage RAW264.7 cells. Moreover, the addition of vitamin K3 before and after LPS administration attenuated the severity of lung injury in an animal model of acute lung injury/acute respiratory distress syndrome (ARDS), which occurs in the setting of acute severe illness complicated by systemic inflammation. In the ARDS model, vitamin K3 also suppressed the LPS-induced increase in the serum TNF-alpha level and inhibited the LPS-evoked nuclear translocation of NF-kappaB in lung tissue. Despite marked efforts, little therapeutic progress has been made, and the mortality rate of ARDS remains high. Vitamin K3 may be an effective therapeutic strategy against acute lung injury including ARDS.

Efficacy of multiple exposure with low level He-Ne laser dose on acute wound healing: a pre-clinical study

NASA Astrophysics Data System (ADS)

Prabhu, Vijendra; Rao, Bola Sadashiva S.; Mahato, Krishna Kishore

2014-02-01

Investigations on the use of Low Level Laser Therapy (LLLT) for wound healing especially with the red laser light have demonstrated its pro-healing potential on a variety of pre-clinical and surgical wounds. However, until now, in LLLT the effect of multiple exposure of low dose laser irradiation on acute wound healing on well-designed pre-clinical model is not much explored. The present study aimed to investigate the effect of multiple exposure of low dose Helium Neon laser on healing progression of full thickness excision wounds in Swiss albino mice. Further, the efficacy of the multiple exposure of low dose laser irradiation was compared with the single exposure of optimum dose. Full thickness excision wounds (circular) of 15 mm diameter were created, and subsequently illuminated with the multiple exposures (1, 2, 3, 4 and 5 exposure/ week until healing) of He-Ne (632.8 nm, 4.02 mWcm-2) laser at 0.5 Jcm-2 along with single exposure of optimum laser dose (2 J/cm-2) and un-illuminated controls. Classical biophysical parameters such as contraction kinetics, area under the curve and the mean healing time were documented as the assessment parameters to examine the efficacy of multiple exposures with low level laser dose. Experimental findings substantiated that either single or multiple exposures of 0.5 J/cm2 failed to produce any detectable alterations on wound contraction, area under the curve and mean healing time compared to single exposure of optimum dose (2 Jcm-2) and un-illuminated controls. Single exposure of optimum, laser dose was found to be ideal for acute wound healing.

Nuclear Weapon Effect Research at PSR (Pacific-Sierra Research Corporation) - 1983. Symptomatology of Acute Radiation Effects in Humans after Exposure to Doses of 75 to 4500 Rads (cGy) Free-in-Air

DTIC Science & Technology

1984-08-31

subsequently published as DNA-TR-81-237 and Chap. II of PSR Report 1241 ). George H. Anno, Acute Radiation Response in lirwans: InJormaZ Conrients by...Radiation Accidents: Medical Aspects of Neutron and Gcama-Ray Exposures, Oak Ridge National Laboratory, Oak Ridge, Tennessee, Report ORNL -2748, Part B

A possible approach to large-scale laboratory testing for acute radiation sickness after a nuclear detonation.

PubMed

Adalja, Amesh A; Watson, Matthew; Wollner, Samuel; Toner, Eric

2011-12-01

After the detonation of an improvised nuclear device, several key actions will be necessary to save the greatest number of lives possible. Among these tasks, the identification of patients with impending acute radiation sickness is a critical problem that so far has lacked a clear solution in national planning. We present one possible solution: the formation of a public-private partnership to augment the capacity to identify those at risk for acute radiation sickness. © Mary Ann Liebert, Inc.

Acute myeloid and chronic lymphoid leukaemias and exposure to low-level benzene among petroleum workers

PubMed Central

Rushton, L; Schnatter, A R; Tang, G; Glass, D C

2014-01-01

Background: High benzene exposure causes acute myeloid leukaemia (AML). Three petroleum case–control studies identified 60 cases (241 matched controls) for AML and 80 cases (345 matched controls) for chronic lymphoid leukaemia (CLL). Methods: Cases were classified and scored regarding uncertainty by two haematologists using available diagnostic information. Blinded quantitative benzene exposure assessment used work histories and exposure measurements adjusted for era-specific circumstances. Statistical analyses included conditional logistic regression and penalised smoothing splines. Results: Benzene exposures were much lower than previous studies. Categorical analyses showed increased ORs for AML with several exposure metrics, although patterns were unclear; neither continuous exposure metrics nor spline analyses gave increased risks. ORs were highest in terminal workers, particularly for Tanker Drivers. No relationship was found between benzene exposure and risk of CLL, although the Australian study showed increased risks in refinery workers. Conclusion: Overall, this study does not persuasively demonstrate a risk between benzene and AML. A previously reported strong relationship between myelodysplastic syndrome (MDS) (potentially previously reported as AML) at our study's low benzene levels suggests that MDS may be the more relevant health risk for lower exposure. Higher CLL risks in refinery workers may be due to more diverse exposures than benzene alone. PMID:24357793

Effect of Hypohydration and Altitude Exposure on Aerobic Exercise Performance and Acute Mountain Sickness

DTIC Science & Technology

2010-09-01

code) 2010 Journal Article-Journal of Applied Physiology Effect of hypohydration and altitude exposure on aerobic exercise performance and acute...1563. Visit our website at http://www.the-aps.org/. Physiological Society, 9650 Rockville Pike, Bethesda MD 20814-3991. Copyright © 2010 by the American... Physiological Society. those papers emphasizing adaptive and integrative mechanisms. It is published 12 times a year (monthly) by the American

Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides).

PubMed

Mehinto, Alvine C; Prucha, Melinda S; Colli-Dula, Reyna C; Kroll, Kevin J; Lavelle, Candice M; Barber, David S; Vulpe, Christopher D; Denslow, Nancy D

2014-07-01

Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20μg/kg of cadmium chloride (mean exposure level - 2.6μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly increased in the liver including genes encoding for the rate limiting steroidogenic acute regulatory protein and the catalytic enzyme 7-dehydrocholesterol reductase. Integration of the transcriptomic data using functional enrichment analyses revealed a number of enriched gene networks associated with previously reported adverse outcomes of cadmium exposure such as liver toxicity and impaired reproduction. Copyright © 2014 Elsevier B.V. All rights

Nerve fiber layer (NFL) degeneration associated with acute q-switched laser exposure in the nonhuman primate

NASA Astrophysics Data System (ADS)

Zwick, Harry; Zuclich, Joseph A.; Stuck, Bruce E.; Gagliano, Donald A.; Lund, David J.; Glickman, Randolph D.

1995-01-01

We have evaluated acute laser retinal exposure in non-human primates using a Rodenstock scanning laser ophthalmoscope (SLO) equipped with spectral imaging laser sources at 488, 514, 633, and 780 nm. Confocal spectral imaging at each laser wavelength allowed evaluation of the image plane from deep within the retinal vascular layer to the more superficial nerve fiber layer in the presence and absence of the short wavelength absorption of the macular pigment. SLO angiography included both fluorescein and indocyanine green procedures to assess the extent of damage to the sensory retina, the retinal pigment epithelium (RPE), and the choroidal vasculature. All laser exposures in this experiment were from a Q-switched Neodymium laser source at an exposure level sufficient to produce vitreous hemorrhage. Confocal imaging of the nerve fiber layer revealed discrete optic nerve sector defects between the lesion site and the macula (retrograde degeneration) as well as between the lesion site and the optic disk (Wallerian degeneration). In multiple hemorrhagic exposures, lesions placed progressively distant from the macula or overlapping the macula formed bridging scars visible at deep retinal levels. Angiography revealed blood flow disturbance at the retina as well as at the choroidal vascular level. These data suggest that acute parafoveal laser retinal injury can involve both direct full thickness damage to the sensory and non-sensory retina and remote nerve fiber degeneration. Such injury has serious functional implications for both central and peripheral visual function.

Adolescent mice are less sensitive to the effects of acute nicotine on context pre-exposure than adults.

PubMed

Kutlu, Munir Gunes; Braak, David C; Tumolo, Jessica M; Gould, Thomas J

2016-07-01

Adolescence is a critical developmental period associated with both increased vulnerability to substance abuse and maturation of certain brain regions important for learning and memory such as the hippocampus. In this study, we employed a hippocampus-dependent learning context pre-exposure facilitation effect (CPFE) paradigm in order to test the effects of acute nicotine on contextual processing during adolescence (post-natal day (PND) 38) and adulthood (PND 53). In Experiment 1, adolescent or adult C57BL6/J mice received either saline or one of three nicotine doses (0.09, 0.18, and 0.36mg/kg) prior to contextual pre-exposure and testing. Our results demonstrated that both adolescent and adult mice showed CPFE in the saline groups. However, adolescent mice only showed acute nicotine enhancement of CPFE with the highest nicotine dose whereas adult mice showed the enhancing effects of acute nicotine with all three doses. In Experiment 2, to determine if the lack of nicotine's effects on CPFE shown by adolescent mice is specific to the age when they are tested, mice were either given contextual pre-exposure during adolescence or adulthood and received immediate shock and testing during adulthood after a 15day delay. We found that both adolescent and adult mice showed CPFE in the saline groups when tested during adulthood. However, like Experiment 1, mice that received contextual pre-exposure during adolescence did not show acute nicotine enhancement except at the highest dose (0.36mg/kg) whereas both low (0.09mg/kg) and high (0.36mg/kg) doses enhanced CPFE in adult mice. Finally, we showed that the enhanced freezing response found with 0.36mg/kg nicotine in the 15-day experiment may be a result of decreased locomotor activity as mice that received this dose of nicotine traveled shorter distances in an open field paradigm. Overall, our results indicate that while adolescent mice showed normal contextual processing when tested both during adolescence and adulthood, they

Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Madden, Jill A.; Hoyer, Patricia B.; Devine, Patrick J.

2014-05-01

Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). Aftermore » four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT{sup Thr308} protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not

Nuclear-weapon-effect research at PSR (Pacific-Sierra Research Corporation) - 1983. Volume 10. Symptomatology of acute radiation effects in humans after exposure to doses of 75 to 4500 rads (cGy) free-in-air. Final technical report, 27 October 1982-30 November 1983

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baum, S.J.; Young, R.W.; Anno, G.H.

1984-08-31

This report distills from available data descriptions of typical human symptoms in reaction to prompt ionizing radiation in the dose range 75 to 4500 rads (cGy) free-in-air. The descriptions correlate symptoms with dose and time over the acute post-exposure period of six weeks. Their purpose is to provide an empirical base for estimating combat troop performance after a nuclear weapon attack. The dose range of interest is subdivided into eight subranges associated with important pathophysiological events. For each subrange, the signs and symptoms manifested by an exposed population are estimated--symptom onset, severity, duration, and incidence. The early or prodromal phasemore » of radiation sickness begins about 2 to 4 hrs after doses of 300 to 530 rads (cGy). Onset time diminishes with dose, occurring within minutes of exposure to 4500 rads (cGy). Characteristic prodromal symptoms are nausea, vomiting, anorexia, and diarrhea. The prodromal phase lasts from several days to a matter of hours, depending on dose. Symptoms of the hemopoietic syndrome are bleeding, fever, infection, and ulceration. Symptoms of the gastrointestinal syndrome are fluid loss, electrolyte imbalance, severe diarrhea, and septicemia.« less

Occupational radiation exposure in nuclear medicine department in Kuwait

NASA Astrophysics Data System (ADS)

Alnaaimi, M.; Alkhorayef, M.; Omar, M.; Abughaith, N.; Alduaij, M.; Salahudin, T.; Alkandri, F.; Sulieman, A.; Bradley, D. A.

2017-11-01

Ionizing radiation exposure is associated with eye lens opacities and cataracts. Radiation workers with heavy workloads and poor protection measures are at risk for vision impairment or cataracts if suitable protection measures are not implemented. The aim of this study was to measure and evaluate the occupational radiation exposure in a nuclear medicine (NM) department. The annual average effective doses (Hp[10] and Hp[0.07]) were measured using calibrated thermos-luminescent dosimeters (TLDs; MCP-N [LiF:Mg,Cu,P]). Five categories of staff (hot lab staff, PET physicians, NM physicians, technologists, and nurses) were included. The average annual eye dose (Hp[3]) for NM staff, based on measurements for a typical yearly workload of >7000 patients, was 4.5 mSv. The annual whole body radiation (Hp[10]) and skin doses (Hp[0.07]) were 4.0 and 120 mSv, respectively. The measured Hp(3), Hp(10), and Hp(0.07) doses for all NM staff categories were below the dose limits described in ICRP 2014 in light of the current practice. The results provide baseline data for staff exposure in NM in Kuwait. Radiation dose optimization measures are recommended to reduce NM staff exposure to its minimal value.

A population-based case-control study on statin exposure and risk of acute diverticular disease.

PubMed

Sköldberg, Filip; Svensson, Tobias; Olén, Ola; Hjern, Fredrik; Schmidt, Peter T; Ljung, Rickard

2016-01-01

A reduced risk of perforated diverticular disease among individuals with current statin exposure has been reported. The aim of the present study was to investigate whether statins reduce the risk of acute diverticular disease. A nation-wide population-based case-control study was performed, including 13,127 cases hospitalised during 2006-2010 with a first-time diagnosis of colonic diverticular disease, and 128,442 control subjects (matched for sex, age, county of residence and calendar year). Emergency surgery, assumed to be a proxy for complicated diverticulitis, was performed on 906 of the cases during the index admission, with 8818 matched controls. Statin exposure was classified as "current" or "former" if a statin prescription was last dispensed ≤ 125 days or >125 days before index date, respectively. The association between statin exposure and acute diverticular disease was investigated by conditional logistic regression, including models adjusting for country of birth, educational level, marital status, comorbidities, nonsteroidal anti-inflammatory drug/steroid exposure and healthcare utilisation. A total of 1959 cases (14.9%) and 16,456 controls (12.8%) were current statin users (crude OR 1.23 [95% CI 1.17-1.30]; fully adjusted OR 1.00 [0.94-1.06]). One hundred and thirty-two of the cases subjected to surgery (14.6%), and 1441 of the corresponding controls (16.3%) were current statin users (crude OR 0.89 [95% CI 0.73-1.08]; fully adjusted OR 0.70 [0.55-0.89]). The results do not indicate that statins affect the development of symptomatic diverticular disease in general. However, current statin use was associated with a reduced risk of emergency surgery for diverticular disease.

The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens

USDA-ARS?s Scientific Manuscript database

Ammonia is a potential health hazard to both humans and animals, causing systemic low-grade inflammation based on its levels and durations. The objective of this study was to examine the effect of 45 weeks of exposure to 30 ppm NH3 on the concentrations of acute phase proteins, immunoglobulins and c...

Acute episodes of predator exposure in conjunction with chronic social instability as an animal model of post-traumatic stress disorder

PubMed Central

Zoladz, Phillip R.; Conrad, Cheryl D.; Fleshner, Monika; Diamond, David M.

2008-01-01

People who are exposed to horrific, life-threatening experiences are at risk for developing post-traumatic stress disorder (PTSD). Some of the symptoms of PTSD include persistent anxiety, exaggerated startle, cognitive impairments and increased sensitivity to yohimbine, an α2-adrenergic receptor antagonist. We have taken into account the conditions known to induce PTSD, as well as factors responsible for long-term maintenance of the disorder, to develop an animal model of PTSD. Adult male Sprague–Dawley rats were administered a total of 31 days of psychosocial stress, composed of acute and chronic components. The acute component was a 1-h stress session (immobilization during cat exposure), which occurred on Days 1 and 11. The chronic component was that on all 31 days the rats were given unstable housing conditions. We found that psychosocially stressed rats had reduced growth rate, reduced thymus weight, increased adrenal gland weight, increased anxiety, an exaggerated startle response, cognitive impairments, greater cardiovascular and corticosterone reactivity to an acute stressor and heightened responsivity to yohimbine. This work demonstrates the effectiveness of acute inescapable episodes of predator exposure administered in conjunction with daily social instability as an animal model of PTSD. PMID:18574787

1H NMR spectroscopic analysis detects metabolic disturbances in rat urine on acute exposure to heavy metal tungsten alloy based metals salt.

PubMed

Tyagi, Ritu; Rana, Poonam; Gupta, Mamta; Bhatnagar, Deepak; Srivastava, Shatakshi; Roy, Raja; Khushu, Subash

2014-03-25

Heavy metal tungsten alloys (HMTAs) have been found to be safer alternatives for making military munitions. Recently, some studies demonstrating the toxic potential of HMTAs have raised concern over the safety issues, and further propose that HMTAs exposure may lead to physiological disturbances as well. To look for the systemic effect of acute toxicity of HMTA based metals salt, (1)H nuclear magnetic resonance ((1)H NMR) spectroscopic profiling of rat urine was carried out. Male Sprague Dawley rats were administered (intraperitoneal) low and high dose of mixture of HMTA based metals salt and NMR spectroscopy was carried out in urine samples collected at 8, 24, 72 and 120 h post dosing (p.d.). Serum biochemical parameters and liver histopathology were also conducted. The (1)H NMR spectra were analysed using multivariate analysis techniques to show the time- and dose-dependent biochemical variations in post HMTA based metals salt exposure. Urine metabolomic analysis showed changes associated with energy metabolism, amino acids, N-methyl nicotinamide, membrane and gut flora metabolites. Multivariate analysis showed maximum variation with best classification of control and treated groups at 24h p.d. At the end of the study, for the low dose group most of the changes at metabolite level reverted to control except for the energy metabolites; whereas, in the high dose group some of the changes still persisted. The observations were well correlated with histopathological and serum biochemical parameters. Further, metabolic pathway analysis clarified that amongst all the metabolic pathways analysed, tricarboxylic acid cycle was most affected at all the time points indicating a switchover in energy metabolism from aerobic to anaerobic. These results suggest that exposure of rats to acute doses of HMTA based metals salt disrupts physiological metabolism with moderate injury to the liver, which might indirectly result from heavy metals induced oxidative stress. Copyright �

Acute Assessment of Traumatic Brain Injury and Post-Traumatic Stress After Exposure to a Deployment-Related Explosive Blast.

PubMed

Baker, Monty T; Moring, John C; Hale, Willie J; Mintz, Jim; Young-McCaughan, Stacey; Bryant, Richard A; Broshek, Donna K; Barth, Jeffrey T; Villarreal, Robert; Lancaster, Cynthia L; Malach, Steffany L; Lara-Ruiz, Jose M; Isler, William; Peterson, Alan L

2018-05-18

Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are two of the signature injuries in military service members who have been exposed to explosive blasts during deployments to Iraq and Afghanistan. Acute stress disorder (ASD), which occurs within 2-30 d after trauma exposure, is a more immediate psychological reaction predictive of the later development of PTSD. Most previous studies have evaluated service members after their return from deployment, which is often months or years after the initial blast exposure. The current study is the first large study to collect psychological and neuropsychological data from active duty service members within a few days after blast exposure. Recruitment for blast-injured TBI patients occurred at the Air Force Theater Hospital, 332nd Air Expeditionary Wing, Joint Base Balad, Iraq. Patients were referred from across the combat theater and evaluated as part of routine clinical assessment of psychiatric and neuropsychological symptoms after exposure to an explosive blast. Four measures of neuropsychological functioning were used: the Military Acute Concussion Evaluation (MACE); the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS); the Headminder Cognitive Stability Index (CSI); and the Automated Neuropsychological Assessment Metrics, Version 4.0 (ANAM4). Three measures of combat exposure and psychological functioning were used: the Combat Experiences Scale (CES); the PTSD Checklist-Military Version (PCL-M); and the Acute Stress Disorder Scale (ASDS). Assessments were completed by a deployed clinical psychologist, clinical social worker, or mental health technician. A total of 894 patients were evaluated. Data from 93 patients were removed from the data set for analysis because they experienced a head injury due to an event that was not an explosive blast (n = 84) or they were only assessed for psychiatric symptoms (n = 9). This resulted in a total of 801 blast-exposed patients for data

Differential effects of 5-HTTLPR genotypes on mood, memory, and attention bias following acute tryptophan depletion and stress exposure.

PubMed

Firk, Christine; Markus, C Rob

2009-05-01

Polymorphisms of the serotonin transporter gene (5-HTTLPR) may be associated with increased vulnerability to acute tryptophan depletion (ATD) and depression vulnerability especially following stressful life events. The aim of the present study was to investigate the effects of ATD in subjects with different 5-HTTLPR profiles before and after stress exposure on affective and cognitive-attentional changes. Eighteen subjects with homozygotic short alleles (S'/S') and 17 subjects with homozygotic long alleles (L'/L') of the 5-HTTLPR participated in a double-blind, placebo-controlled, crossover design to measure the effects of ATD on mood, memory, and attention before and after acute stress exposure. ATD lowered mood in all subjects independent of genotype. In S'/S' genotypes, mild acute stress increased depressive mood and in L'/L' genotypes increased feelings of vigor. Furthermore, S'/S' genotypes differed from L'/L' genotypes on measures of attention independent of treatment and memory following ATD. Polymorphisms of the 5-HTTLPR differentially affect responses to mild stress and ATD, suggesting greater vulnerability of S'/S' carriers to serotonergic manipulations and supporting increased depression vulnerability.

The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Bo; State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing 100101; Xia Jing

Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unitmore » responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.« less

Cancer risk in nuclear workers occupationally exposed to uranium-emphasis on internal exposure.

PubMed

Canu, Irina Guseva; Ellis, Elizabeth Dupree; Tirmarche, Margot

2008-01-01

Workers involved in the nuclear fuel cycle have a potential for internal exposure to uranium. The present review of epidemiological studies of these workers aims to elucidate the relationship between occupational internal uranium exposure and cancer risk. Eighteen cohort and 5 nested case-control studies published since 1980 are reviewed. Workers occupationally exposed to uranium appear to be at increased risk of mortality from neoplasms of the lung, larynx, and lymphatic and haematopoietic tissue. Currently available evidence for a positive association between internal exposure to uranium and the risk of cancer is limited. The common weaknesses in reviewed studies include low statistical power and inaccurate assessment of internal exposure to uranium. Further investigations should focus on precise assessment of occupational exposure and address the issue of potential confounders.

Reduction of radiation exposure in Japanese BWR Nuclear Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morikawa, Yoshitake

1995-03-01

The reduction of occupational exposure to radiation during the annual inspection and maintenance outages of Japanese boiling water reactors (BWR) is one of the most important objectives for stable and reliable operation. It was shown that this radiation exposure is caused by radionuclides, such as Co-60, Co-58 and Mn-54 which are produced from the metal elements Co, Ni, and Fe present in the corrosion products of structural materials that had been irradiated by neutrons. Therefore, to reduce radiation sources and exposures in Japanese BWRs, attempts have been reinforced to remove corrosion products and activated corrosion products from the primary coolantmore » system. This paper describes the progress of the application of these measures to Japanese BWRs. Most Japanese BWR-4 and BWR-5 type nuclear power plants started their commercial operations during the 1970s. With the elapse of time during operations, a problem came to the forefront, namely that occupational radiation exposure during plant outages gradually increased, which obstructed the smooth running of inspections and maintenance work. To overcome this problem, extensive studies to derive effective countermeasures for radiation exposure reduction were undertaken, based on the evaluation of the plants operation data.« less

Physiological responses to acute cold exposure in young lean men

PubMed Central

Martinez-Tellez, Borja; Sanchez-Delgado, Guillermo; A. Alcantara, Juan M.; Acosta-Manzano, Pedro; Morales-Artacho, Antonio J.; R. Ruiz, Jonatan

2018-01-01

The aim of this study was to comprehensively describe the physiological responses to an acute bout of mild cold in young lean men (n = 11, age: 23 ± 2 years, body mass index: 23.1 ± 1.2 kg/m2) to better understand the underlying mechanisms of non-shivering thermogenesis and how it is regulated. Resting energy expenditure, substrate metabolism, skin temperature, thermal comfort perception, superficial muscle activity, hemodynamics of the forearm and abdominal regions, and heart rate variability were measured under warm conditions (22.7 ± 0.2°C) and during an individualized cooling protocol (air-conditioning and water cooling vest) in a cold room (19.4 ± 0.1°C). The temperature of the cooling vest started at 16.6°C and decreased ~ 1.4°C every 10 minutes until participants shivered (93.5 ± 26.3 min). All measurements were analysed across 4 periods: warm period, at 31% and at 64% of individual´s cold exposure time until shivering occurred, and at the shivering threshold. Energy expenditure increased from warm period to 31% of cold exposure by 16.7% (P = 0.078) and to the shivering threshold by 31.7% (P = 0.023). Fat oxidation increased by 72.6% from warm period to 31% of cold exposure (P = 0.004), whereas no changes occurred in carbohydrates oxidation. As shivering came closer, the skin temperature and thermal comfort perception decreased (all P<0.05), except in the supraclavicular skin temperature, which did not change (P>0.05). Furthermore, the superficial muscle activation increased at the shivering threshold. It is noteworthy that the largest physiological changes occurred during the first 30 minutes of cold exposure, when the participants felt less discomfort. PMID:29734360

Cumulative toxicity of neonicotinoid insecticide mixtures to Chironomus dilutus under acute exposure scenarios.

PubMed

Maloney, Erin M; Morrissey, Christy A; Headley, John V; Peru, Kerry M; Liber, Karsten

2017-11-01

Extensive agricultural use of neonicotinoid insecticide products has resulted in the presence of neonicotinoid mixtures in surface waters worldwide. Although many aquatic insect species are known to be sensitive to neonicotinoids, the impact of neonicotinoid mixtures is poorly understood. In the present study, the cumulative toxicities of binary and ternary mixtures of select neonicotinoids (imidacloprid, clothianidin, and thiamethoxam) were characterized under acute (96-h) exposure scenarios using the larval midge Chironomus dilutus as a representative aquatic insect species. Using the MIXTOX approach, predictive parametric models were fitted and statistically compared with observed toxicity in subsequent mixture tests. Single-compound toxicity tests yielded median lethal concentration (LC50) values of 4.63, 5.93, and 55.34 μg/L for imidacloprid, clothianidin, and thiamethoxam, respectively. Because of the similar modes of action of neonicotinoids, concentration-additive cumulative mixture toxicity was the predicted model. However, we found that imidacloprid-clothianidin mixtures demonstrated response-additive dose-level-dependent synergism, clothianidin-thiamethoxam mixtures demonstrated concentration-additive synergism, and imidacloprid-thiamethoxam mixtures demonstrated response-additive dose-ratio-dependent synergism, with toxicity shifting from antagonism to synergism as the relative concentration of thiamethoxam increased. Imidacloprid-clothianidin-thiamethoxam ternary mixtures demonstrated response-additive synergism. These results indicate that, under acute exposure scenarios, the toxicity of neonicotinoid mixtures to C. dilutus cannot be predicted using the common assumption of additive joint activity. Indeed, the overarching trend of synergistic deviation emphasizes the need for further research into the ecotoxicological effects of neonicotinoid insecticide mixtures in field settings, the development of better toxicity models for neonicotinoid mixture

Haemodynamic changes in ipsilateral and contralateral fingers caused by acute exposures to hand transmitted vibration.

PubMed Central

Bovenzi, M; Griffin, M J

1997-01-01

OBJECTIVES: To investigate changes in digital circulation during and after exposure to hand transmitted vibration. By studying two frequencies and two magnitudes of vibration, to investigate the extent to which haemodynamic changes depend on the vibration frequency, the vibration acceleration, and the vibration velocity. METHODS: Finger skin temperature (FST), finger blood flow (FBF), and finger systolic pressure were measured in the fingers of both hands in eight healthy men. Indices of digital vasomotor tone-such as critical closing pressure and vascular resistance-were estimated by pressure-flow curves obtained with different hand heights. With a static load of 10 N, the right hand was exposed for 30 minutes to each of the following root mean squared (rms) acceleration magnitudes and frequencies of vertical vibration: 22 m.s-2 at 31.5 Hz, 22 m.s-2 at 125 Hz, and 87 m.s-2 at 125 Hz. A control condition consisted of exposure to the static load only. The measures of digital circulation and vasomotor tone were taken before exposure to the vibration and the static load, and at 0, 20, 40, and 60 minutes after the end of each exposure. RESULTS: Exposure to static load caused no significant changes in FST, FBF, or indices of vasomotor tone in either the vibrated right middle finger or the non-vibrated left middle finger. In both fingers, exposure to vibration of 125 Hz and 22 m.s-2 produced a greater reduction in FBF and a greater increase in vasomotor tone than did vibration of 31.5 Hz and 22 m.s-2. In the vibrated right finger, exposure to vibration of 125 Hz and 87 m.s-2 provoked an immediate vasodilation which was followed by vasoconstriction during recovery. The non-vibrated left finger showed a significant increase in vasomotor tone throughout the 60 minute period after the end of vibration exposure. CONCLUSIONS: The digital circulatory response to acute vibration depends upon the magnitude and frequency of the vibration stimulus. Vasomotor mechanisms, mediated

Acute vertigo in an anesthesia provider during exposure to a 3T MRI scanner

PubMed Central

Gorlin, Andrew; Hoxworth, Joseph M; Pavlicek, William; Thunberg, Christopher A; Seamans, David

2015-01-01

Vertigo induced by exposure to the magnetic field of a magnetic resonance imaging (MRI) scanner is a well-known phenomenon within the radiology community but is not widely appreciated by other clinical specialists. Here, we describe a case of an anesthetist experiencing acute vertigo while providing sedation to a patient undergoing a 3 Tesla MRI scan. After discussing previous reports, and the evidence surrounding MRI-induced vertigo, we review potential etiologies that include the effects of both static and time-varying magnetic fields on the vestibular apparatus. We conclude our review by discussing the occupational standards that exist for MRI exposure and methods to minimize the risks of MRI-induced vertigo for clinicians working in the MRI environment. PMID:25792858

Influence of dissolved organic carbon on toxicity of copper to a unionid mussel (Villosa iris) and a cladoceran (Ceriodaphnia dubia) in acute and chronic water exposures

USGS Publications Warehouse

Wang, Ning; Mebane, Christopher A.; Kunz, James L.; Ingersoll, Christopher G.; Brumbaugh, William G.; Santore, Robert C.; Gorsuch, Joseph W.; Arnold, W. Ray

2011-01-01

Acute and chronic toxicity of copper (Cu) to a unionid mussel (Villosa iris) and a cladoceran (Ceriodaphnia dubia) were determined in water exposures at four concentrations of dissolved organic carbon (DOC; nominally 0.5, 2.5, 5, and 10 mg/L as carbon [C]). Test waters with DOC concentrations of 2.5 to 10 mg C/L were prepared by mixing a concentrate of natural organic matter (Suwannee River, GA, USA) in diluted well water (hardness 100 mg/L as CaCO3, pH 8.3, DOC 0.5 mg C/L). Acute median effect concentrations (EC50s) for dissolved Cu increased approximately fivefold (15–72 μg Cu/L) for mussel survival in 4-d exposures and increased about 11-fold (25–267 μg Cu/L) for cladoceran survival in 2-d exposures across DOC concentrations from 0.5 to 10 mg C/L. Similarly, chronic 20% effect concentrations (EC20s) for the mussel in 28-d exposures increased about fivefold (13–61 μg Cu/L for survival; 8.8–38 μg Cu/L for biomass), and the EC20s for the cladoceran in 7-d exposures increased approximately 17-fold (13–215 μg Cu/L) for survival or approximately fourfold (12–42 μg Cu/L) for reproduction across DOC concentrations from 0.5 to 10 mg C/L. The acute and chronic values for the mussel were less than or approximately equal to the values for the cladoceran. Predictions from the biotic ligand model (BLM) used to derive the U.S. Environmental Protection Agency's ambient water quality criteria (AWQC) for Cu explained more than 90% of the variation in the acute and chronic endpoints for the two species, with the exception of the EC20 for cladoceran reproduction (only 46% of variation explained). The BLM-normalized acute EC50s and chronic EC20s for the mussel and BLM-normalized chronic EC20s for the cladoceran in waters with DOC concentrations of 2.5 to 10 mg C/L were equal to or less than the final acute value and final chronic value in the BLM-based AWQC for Cu, respectively, indicating that the Cu AWQC might not adequately protect the mussel from acute and

OCCUPATIONAL EXPOSURE OF NMR SPECTROMETRISTS TO STATIC AND RADIOFREQUENCY FIELDS.

PubMed

Berlana, Tania; Úbeda, Alejandro

2017-12-01

Occupational exposure to static and radiofrequency fields emitted by nuclear magnetic resonance spectrometers was assessed through systematic field metering during operation of 19 devices in nine research centers. Whereas no measurable levels of radiofrequency radiation were registered outside the spectrometers, significant exposure to static field was detected, with maximum values recorded at the user's hand (B = 683.00 mT) and head-thorax (B = 135.70 mT) during spectrometer manipulation. All values were well below the exposure limits set by the European standard for workers protection against the effects of acute field exposure only. As for potential effects of chronic exposure, waiting for more complete knowledge, adoption of technical and operational strategies for exposure minimizing is advisable. In this respect, the data revealed that compared with standard magnetic shielding, ultrashield technology allows a 20-65-fold reduction of the field strength received by the operator. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pesticide exposure in children.

PubMed

Roberts, James R; Karr, Catherine J

2012-12-01

Pesticides are a collective term for a wide array of chemicals intended to kill unwanted insects, plants, molds, and rodents. Food, water, and treatment in the home, yard, and school are all potential sources of children's exposure. Exposures to pesticides may be overt or subacute, and effects range from acute to chronic toxicity. In 2008, pesticides were the ninth most common substance reported to poison control centers, and approximately 45% of all reports of pesticide poisoning were for children. Organophosphate and carbamate poisoning are perhaps the most widely known acute poisoning syndromes, can be diagnosed by depressed red blood cell cholinesterase levels, and have available antidotal therapy. However, numerous other pesticides that may cause acute toxicity, such as pyrethroid and neonicotinoid insecticides, herbicides, fungicides, and rodenticides, also have specific toxic effects; recognition of these effects may help identify acute exposures. Evidence is increasingly emerging about chronic health implications from both acute and chronic exposure. A growing body of epidemiological evidence demonstrates associations between parental use of pesticides, particularly insecticides, with acute lymphocytic leukemia and brain tumors. Prenatal, household, and occupational exposures (maternal and paternal) appear to be the largest risks. Prospective cohort studies link early-life exposure to organophosphates and organochlorine pesticides (primarily DDT) with adverse effects on neurodevelopment and behavior. Among the findings associated with increased pesticide levels are poorer mental development by using the Bayley index and increased scores on measures assessing pervasive developmental disorder, inattention, and attention-deficit/hyperactivity disorder. Related animal toxicology studies provide supportive biological plausibility for these findings. Additional data suggest that there may also be an association between parental pesticide use and adverse birth

Pesticide Exposure in Children

PubMed Central

Roberts, James R.; Karr, Catherine J.

2018-01-01

Pesticides are a collective term for a wide array of chemicals intended to kill unwanted insects, plants, molds, and rodents. Food, water, and treatment in the home, yard, and school are all potential sources of children’s exposure. Exposures to pesticides may be overt or subacute, and effects range from acute to chronic toxicity. In 2008, pesticides were the ninth most common substance reported to poison control centers, and approximately 45% of all reports of pesticide poisoning were for children. Organophosphate and carbamate poisoning are perhaps the most widely known acute poisoning syndromes, can be diagnosed by depressed red blood cell cholinesterase levels, and have available antidotal therapy. However, numerous other pesticides that may cause acute toxicity, such as pyrethroid and neonicotinoid insecticides, herbicides, fungicides, and rodenticides, also have specific toxic effects; recognition of these effects may help identify acute exposures. Evidence is increasingly emerging about chronic health implications from both acute and chronic exposure. A growing body of epidemiological evidence demonstrates associations between parental use of pesticides, particularly insecticides, with acute lymphocytic leukemia and brain tumors. Prenatal, household, and occupational exposures (maternal and paternal) appear to be the largest risks. Prospective cohort studies link early-life exposure to organophosphates and organochlorine pesticides (primarily DDT) with adverse effects on neurodevelopment and behavior. Among the findings associated with increased pesticide levels are poorer mental development by using the Bayley index and increased scores on measures assessing pervasive developmental disorder, inattention, and attention-deficit/hyperactivity disorder. Related animal toxicology studies provide supportive biological plausibility for these findings. Additional data suggest that there may also be an association between parental pesticide use and adverse birth

The change of nuclear LC3 distribution in acute myeloid leukemia cells.

PubMed

Guo, Wenjian; Jin, Jingrui; Pan, Jiajia; Yao, Rongxing; Li, Xia; Huang, Xin; Ma, Zhixing; Huang, Sujuan; Yan, Xiao; Jin, Jie; Dong, Aishu

2018-05-09

Making sure the change of nuclear LC3 distribution in the autophagy of acute myeloid leukemia (AML) cell and finding out the regulation mechanism may lead to a breakthrough for killing AML cells. Western blots were performed to assess the expression of autophagy proteins. Changes in the LC3 distribution were monitored by immunofluorescence assays together with western blots, and the expression levels of Sirt1, DOR, Beclin1, HMGB1, and AMPK mRNA were detected via fluorescent quantitative PCR. The effects of Sirt1 and DOR on cell proliferation and survival were analyzed by MTT, flow cytometry, and western blotting assays. We found that treating AML cells with Ara-c or Sorafenib resulted in autophagy enhancement, and when autophagy was enhanced, nuclear LC3 moved into the cytoplasm. Notably, when autophagy was inhibited by blocking the nuclear LC3 shift, the cytotoxicity of drugs was enhanced. Our results also identified Sirt1 and DOR as regulatory molecules for the observed nuclear LC3 shift, and these molecules further affected the expression of Beclin1, HMGB1, and AMPK. Our results suggest the distribution of nuclear LC3 can be a novel way for further studying death of AML cells,and the regulatory molecules may be new targets for treating AML. Copyright © 2018 Elsevier Inc. All rights reserved.

Biphasic changes in fetal heart rate variability in preterm fetal sheep developing hypotension after acute on chronic lipopolysaccharide exposure.

PubMed

Lear, Christopher A; Davidson, Joanne O; Booth, Lindsea C; Wassink, Guido; Galinsky, Robert; Drury, Paul P; Fraser, Mhoyra; Bennet, Laura; Gunn, Alistair J

2014-08-15

Perinatal exposure to infection is highly associated with adverse outcomes. Experimentally, acute, severe exposure to gram-negative bacterial lipopolysaccharide (LPS) is associated with increased fetal heart rate variability (FHRV). It is unknown whether FHRV is affected by subclinical infection with or without acute exacerbations. We therefore tested the hypothesis that FHRV would be associated with hypotension after acute on chronic exposure to LPS. Chronically instrumented fetal sheep at 0.7 gestation were exposed to a continuous low-dose LPS infusion (n = 12, 100 ng/kg over 24 h, followed by 250 ng·kg(-1)·24 h(-1) for a further 96 h) or the same volume of saline (n = 10). Boluses of either 1 μg LPS or saline were given at 48, 72, and 96 h. Low-dose infusion was not associated with hemodynamic or FHRV changes. The first LPS bolus was associated with tachycardia and suppression of nuchal electromyographic activity in all fetuses. Seven of twelve fetuses developed hypotension (a fall in mean arterial blood pressure ≥5 mmHg). FHRV was transiently increased only at the onset of hypotension, in association with increased cytokine induction and electroencephalogram suppression. FHRV then fell before the nadir of hypotension, with transient suppression of short-term FHRV. After the second LPS bolus, the hypotension group showed a biphasic pattern of a transient increase in FHRV followed by more prolonged suppression. These findings suggest that infection-related hypotension in the preterm fetus mediates the transient increase in FHRV and that repeated exposure to LPS leads to progressive loss of FHRV. Copyright © 2014 the American Physiological Society.

Multicenter field trial on possible health effects of toluene. II. Cross-sectional evaluation of acute low-level exposure.

PubMed

Neubert, D; Gericke, C; Hanke, B; Beckmann, G; Baltes, M M; Kühl, K P; Bochert, G; Hartmann, J

2001-11-15

Data on possible acute effects of today's relevant low-level exposure to toluene are contradictory, and information on possible effects of exposure under occupational conditions is largely lacking. In a controlled, multi-center, blinded field trial, effects possibly associated with acute toluene exposure were evaluated in workers of 12 German rotogravure factories. Medical examinations (inquiries on subjective symptoms, and standard tests of psycho-physiological and psycho-motor functions) were performed on almost 1500 volunteers, of whom 1290 were toluene-exposed (1178 men and 112 women), and about 200 participants served as references (157 men and 37 women), but the main aim of the trial was to reveal dose-response relationships. All volunteers were of the morning work-shift (6 h exposure). Both individual ambient air concentrations (time-weighted average) during the work-shift, as well as blood toluene concentrations after the work-shift were measured. Therefore, the medical data could for the first time be correlated with the actual individual body burden (blood toluene level) at the time of testing. In order to largely exclude confounding by chronic toluene exposure, kinetic measurements as well as the psycho-physiological and psycho-motoric tests were performed before and after the work-shift. Except for minor statistical deviations, neither convincing dose-dependent acute effects could be demonstrated with regression analyses in male volunteers at the exposure levels evaluated, nor were significant differences found when applying group statistics (highly toluene-exposed group versus volunteers with negligible exposure). Due to the rather large number of participants, the predictive power of the study is high, especially when compared with previous publications. In two psycho-physiological tests, a few more female volunteers with quite low toluene body burdens (<340 microg/l blood) showed relatively low scores when compared with participants of the reference

Inability of populations of Callosobruchus maculatus to develop tolerance to exposures of acute gamma irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brower, J.H.

1974-03-01

The reproductive capacity and resistance to an acute dose of gamma irradiation were determined for populations of Callosobruchus maculatus treated with substerilizing doses of irradiation each generation for 30 generations. Reproductive capacity was decreased by an ancestral history of irradiation, the reduction being positively correlated with both the size of dose per generation and the number of ancestral generations treated. Irradiation of the selected populations with an acute dose revealed no increase in tolerance, even after 30 generations. In general, the greater the amount of accumulated ancestral exposure to irradiation, the greater the sensitivity to further irradiation. The ability tomore » develop a tolerance to ionizing irradiation may not be a general phenomenon in insects. (auth)« less

Effects of Acute Exposures to Carbon Dioxide upon Cognitive Functions

NASA Technical Reports Server (NTRS)

Ryder, V. E.; Scully, R. R.; Alexander, D. J.; Lam, C. W.; Young, M.; Satish, U.; Basner, M.

2017-01-01

Carbon dioxide (CO2) originates from human metabolism and typically remains about 10-fold higher in concentration on the International Space Station (ISS) than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the ISS that associates CO2 levels with reports of headaches by crewmembers. Consequently, flight rules have been employed to control CO2 below 3 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached, and there is evidence that CO2 has effects at levels below the threshold for headaches. This concern appears to be substantiated in reports that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. Therefore, we set out to determine if decision-making under volatile, uncertain, confusing and ambiguous circumstances, where feedback is delayed or absent, is correlated with low levels of CO2 during acute exposures (several hours) in crew-like subjects and to determine if additional cognitive domains are sensitive to concentrations of CO2 at, or below, current ISS levels by using a test battery that is currently available onboard ISS. We enrolled 22 volunteers (8 females, 14 males) between the ages of 30-55 (38.8 +/- 7.0) years whose training and professional experience reflect that of the astronaut corps. Subjects were divided among 4 study

Chronic and Acute Ozone Exposure in the Week Prior to Delivery Is Associated with the Risk of Stillbirth

PubMed Central

Ha, Sandie; Pollack, Anna Z.; Zhu, Yeyi; Seeni, Indulaxmi; Kim, Sung Soo; Sherman, Seth; Liu, Danping

2017-01-01

Chronic and acute air pollution has been studied in relation to stillbirth with inconsistent findings. We examined stillbirth risk in a retrospective cohort of 223,375 singleton deliveries from 12 clinical sites across the United States. Average criteria air pollutant exposure was calculated using modified Community Multiscale Air Quality models for the day of delivery and each of the seven days prior, whole pregnancy, and first trimester. Poisson regression models using generalized estimating equations estimated the relative risk (RR) of stillbirth and 95% confidence intervals (CI) in relation to an interquartile range increase in pollutant with adjustment for temperature, clinical, and demographic factors. Ozone (O3) was associated with a 13–22% increased risk of stillbirth on days 2, 3, and 5–7 prior to delivery in single pollutant models, and these findings persisted in multi-pollutant models for days 5 (RR = 1.22, CI = 1.07–1.38) and 6 (RR = 1.18, CI = 1.04–1.33). Whole pregnancy and first trimester O3 increased risk 18–39% in single pollutant models. Maternal asthma increased stillbirth risk associated with chronic PM2.5 and carbon monoxide exposures. Both chronic and acute O3 exposure consistently increased stillbirth risk, while the role of other pollutants varied. Approximately 8000 stillbirths per year in the US may be attributable to O3 exposure. PMID:28684711

Malondialdehyde-Derived Epitopes In Human Skin Result From Acute Exposure To Solar UV And Occur In Nonmelanoma Skin Cancer Tissue

PubMed Central

Williams, Joshua D.; Bermudez, Yira; Park, Sophia L.; Stratton, Steven P.; Uchida, Koji; Hurst, Craig A.; Wondrak, Georg T.

2014-01-01

Cutaneous exposure to solar ultraviolet radiation (UVR) is a causative factor in photoaging and photocarcinogenesis. In human skin, oxidative stress is widely considered a key mechanism underlying the detrimental effects of acute and chronic UVR exposure. The lipid peroxidation product malondialdehyde (MDA) accumulates in tissue under conditions of increased oxidative stress, and the occurrence of MDA-derived protein epitopes, including dihydropyridine-lysine (DHP), has recently been substantiated in human skin. Here we demonstrate for the first time that acute exposure to sub-apoptogenic doses of solar simulated UV light (SSL) causes the formation of free MDA and protein-bound MDA-derived epitopes in cultured human HaCaT keratinocytes and healthy human skin. Immunohistochemical staining revealed that acute exposure to SSL is sufficient to cause an almost twenty-fold increase in general MDA- and specific DHP-epitope content in human skin. When compared to dose-matched solar simulated UVA, complete SSL was more efficient generating both free MDA and MDA-derived epitopes. Subsequent tissue microarray (TMA) analysis revealed the prevalence of MDA- and DHP-epitopes in nonmelanoma skin cancer (NMSC). In squamous cell carcinoma tissue, both MDA- and DHP-epitopes were increased more than three-fold as compared to adjacent normal tissue. Taken together, these date demonstrate the occurrence of MDA-derived epitopes in both solar UVR-exposed healthy human skin and NMSC TMA tissue; however, the potential utility of these epitopes as novel biomarkers of cutaneous photodamage and a functional role in the process of skin photocarcinogenesis remain to be explored. PMID:24584085

Malondialdehyde-derived epitopes in human skin result from acute exposure to solar UV and occur in nonmelanoma skin cancer tissue.

PubMed

Williams, Joshua D; Bermudez, Yira; Park, Sophia L; Stratton, Steven P; Uchida, Koji; Hurst, Craig A; Wondrak, Georg T

2014-03-05

Cutaneous exposure to solar ultraviolet radiation (UVR) is a causative factor in photoaging and photocarcinogenesis. In human skin, oxidative stress is widely considered a key mechanism underlying the detrimental effects of acute and chronic UVR exposure. The lipid peroxidation product malondialdehyde (MDA) accumulates in tissue under conditions of increased oxidative stress, and the occurrence of MDA-derived protein epitopes, including dihydropyridine-lysine (DHP), has recently been substantiated in human skin. Here we demonstrate for the first time that acute exposure to sub-apoptogenic doses of solar simulated UV light (SSL) causes the formation of free MDA and protein-bound MDA-derived epitopes in cultured human HaCaT keratinocytes and healthy human skin. Immunohistochemical staining revealed that acute exposure to SSL is sufficient to cause an almost twenty-fold increase in general MDA- and specific DHP-epitope content in human skin. When compared to dose-matched solar simulated UVA, complete SSL was more efficient generating both free MDA and MDA-derived epitopes. Subsequent tissue microarray (TMA) analysis revealed the prevalence of MDA- and DHP-epitopes in nonmelanoma skin cancer (NMSC). In squamous cell carcinoma tissue, both MDA- and DHP-epitopes were increased more than threefold as compared to adjacent normal tissue. Taken together, these date demonstrate the occurrence of MDA-derived epitopes in both solar UVR-exposed healthy human skin and NMSC TMA tissue; however, the potential utility of these epitopes as novel biomarkers of cutaneous photodamage and a functional role in the process of skin photocarcinogenesis remain to be explored. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi)

NASA Technical Reports Server (NTRS)

Ortiz, R. M.; Patterson, R. M.; Wade, C. E.; Byers, F. M.

2000-01-01

Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

Acute mobile phones exposure affects frontal cortex hemodynamics as evidenced by functional near-infrared spectroscopy.

PubMed

Curcio, Giuseppe; Ferrara, Michele; Limongi, Tania; Tempesta, Daniela; Di Sante, Gabriele; De Gennaro, Luigi; Quaresima, Valentina; Ferrari, Marco

2009-05-01

This study aimed to evaluate by functional near-infrared spectroscopy (fNIRS), the effects induced by an acute exposure (40 mins) to a GSM (Global System for Mobile Communications) signal emitted by a mobile phone (MP) on the oxygenation of the frontal cortex. Eleven healthy volunteers underwent two sessions (Real and Sham exposure) after a crossover, randomized, double-blind paradigm. The whole procedure lasted 60 mins: 10-mins baseline (Bsl), 40-mins (Exposure), and 10-mins recovery (Post-Exp). Together with frontal hemodynamics, heart rate, objective and subjective vigilance, and self-evaluation of subjective symptoms were also assessed. The fNIRS results showed a slight influence of the GSM signal on frontal cortex, with a linear increase in [HHb] as a function of time in the Real exposure condition (F(4,40)=2.67; P=0.04). No other measure showed any GSM exposure-dependent changes. These results suggest that fNIRS is a convenient tool for safely and noninvasively investigating the cortical activation in MP exposure experimental settings. Given the short-term effects observed in this study, the results should be confirmed on a larger sample size and using a multichannel instrument that allows the investigation of a wider portion of the frontal cortex.

El Salvador earthquakes: relationships among acute stress disorder symptoms, depression, traumatic event exposure, and resource loss.

PubMed

Sattler, David N; de Alvarado, Ana Maria Glower; de Castro, Norma Blandon; Male, Robert Van; Zetino, A M; Vega, Raphael

2006-12-01

Four and seven weeks after powerful earthquakes in El Salvador, the authors examined the relationships among demographics, traumatic event exposure, social support, resource loss, acute stress disorder (ASD) symptoms, depression, and posttraumatic growth. Participants were 253 college students (Study 1) and 83 people in the community (Study 2). In Study 1, female gender, traumatic event exposure, low social support, and loss of personal characteristic, condition, and energy resources contributed to ASD symptoms and depression. In Study 2, damage to home and loss of personal characteristic and object resources contributed to ASD symptoms and depression. Posttraumatic growth was not associated with ASD symptoms or depression. Findings support the conservation of resources stress theory (Hobfoll, 1998). Resource loss spirals, excessive demands on coping, and exposure to multiple disasters are discussed.

Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF

NASA Astrophysics Data System (ADS)

Adibzadeh, F.; van Rhoon, G. C.; Verduijn, G. M.; Naus-Postema, N. C.; Paulides, M. M.

2016-01-01

The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg-1) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients’ feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R 2  =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature

Experimental exposure of male volunteers to N-methyl-2-pyrrolidone (NMP): acute effects and pharmacokinetics of NMP in plasma and urine.

PubMed Central

Akesson, B; Paulsson, K

1997-01-01

OBJECTIVES: To study the acute effects of exposure to the increasingly used solvent, N-methyl-2-pyrrolidone (NMP) in male volunteers. Further, to determine the NMP concentration in plasma and urine during and after the exposure. METHODS: Six male volunteers were exposed for eight hours on four different days to 0, 10, 25, and 50 mg/m3 NMP. Plasma was collected and urine was sampled during and after the exposure. Changes in nasal volume were measured by acoustic rhinometry and in airway resistance by spirometry. RESULTS: The eight-hour experimental exposure to 10, 25, and 50 mg/m3 did not induce discomfort to eyes or upper airways. Acute changes in nasal volume were not found, and no changes in the spirometric data could be registered. The elimination curves suggested a non-linear pattern and at the end of exposure showed mean (range) half lifes of NMP in plasma of about 4.0 (2.9-5.8) hours and in urine 4.5 (3.5-6.6) hours. The unmetabolised NMP found in urine samples collected during exposure and at the subsequent 44 hours corresponded to about 2% of the calculated absorbed dose. At the end of the exposure there was a close correlation between exposures and the plasma concentration and urinary excretion of NMP. CONCLUSIONS: NMP was absorbed through the respiratory tract and readily eliminated from the body, mainly by biotransformation to other compounds. Exposure to 10, 25, or 50 mg/m3 NMP did not cause nose, eye, or airway irritation. Thus, NMP is a mild irritant. PMID:9166128

Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

2016-01-01

Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

2015-01-01

Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are a documented concern for human exploration of space. Acute CNS risks include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

Acute Exposure to Air Pollution Triggers Atrial Fibrillation

PubMed Central

Link, Mark S.; Luttmann-Gibson, Heike; Schwartz, Joel; Mittleman, Murray A.; Wessler, Benjamin; Gold, Diane R.; Dockery, Douglas W.; Laden, Francine

2013-01-01

Objective The aim of the present study is to evaluate the association of air pollution with the onset of atrial fibrillation (AF). Background Air pollution in general and more specifically particulate matter has been associated with cardiovascular events. Although ventricular arrhythmias are traditionally thought to convey the increased cardiovascular risk, AF may also contribute. Methods Patients with dual chamber implantable cardioverter defibrillators (ICDs) were enrolled and followed prospectively. The association of AF onset with air quality including ambient PM2.5, black carbon, sulfate, particle number, NO2, SO2, and O3 in the 24 hours prior to the arrhythmia was examined utilizing a case-crossover analysis. In sensitivity analyses, associations with air pollution between 2 and 48 hours prior to the AF were examined. Results Of 176 patients followed for an average of 1.9 years, 49 patients had 328 episodes of AF lasting ≥ 30 seconds. Positive but nonsignificant associations were found for PM2.5 in the prior 24 hours, but stronger associations were found with shorter exposure windows. The odds of AF increased by 26% (95% CI 8% to 47%) for each 6.0 µg/m3 increase in PM2.5 in the 2 hours prior to the event (p=0.004). The odds of AF was highest at the upper quartile of mean PM2.5. Conclusion Particulate matter was associated with increased odds of AF onset within hours following exposure in patients with known cardiac disease. Air pollution is an acute trigger of AF, likely contributing to the pollution-associated adverse cardiac outcomes observed in epidemiological studies. PMID:23770178

Caudate neuronal recording in freely behaving animals following acute and chronic dose response methylphenidate exposure

PubMed Central

Claussen, Catherine M; Dafny, Nachum

2016-01-01

The misuse and abuse of the psychostimulant, methylphenidate (MPD) the drug of choice in the treatment of attention deficit hyperactivity disorder (ADHD) has seen a sharp uprising in recent years among both youth and adults for its cognitive enhancing effects and for recreational purposes. This uprise in illicit use has lead to many questions concerning the long term consequences of MPD exposure. The objective of this study was to record animal behavior concomitantly with the caudate nucleus (CN) neuronal activity following acute and repetitive (chronic) dose response exposure to methylphenidate (MPD). A saline control and three MPD dose (0.6, 2.5, and 10.0 mg/kg) groups were used. Behaviorally, the same MPD dose in some animals following chronic MPD exposure elicited behavioral sensitization and other animals elicited behavioral tolerance. Based on this finding, the CN neuronal population recorded from animals expressing behavioral sensitization were also evaluated separately from CN neurons recorded from animals expressing behavioral tolerance to chronic MPD exposure, respectively. Significant differences in CN neuronal population responses between the behaviorally sensitized and the behaviorally tolerant animals was observed for the 2.5 and 10.0 mg/kg MPD exposed groups. For 2.5 mg/kg MPD, behaviorally sensitized animals responded by decreasing their firing rates while behaviorally tolerant animals showed mainly an increase in their firing rates. The CN neuronal responses recorded from the behaviorally sensitized animals following 10.0 mg/kg MPD responded by increasing their firing rates whereas the CN neuronal recordings from the behaviorally tolerant animals showed that approximately half decreased their firing rates in response to 10.0 mg/kg MPD exposure. The comparison of percentage change in neuronal firing rates showed that the behaviorally tolerant animals trended to exhibit increases in their neuronal firing rates at ED1 following initial MPD exposure

What the Erythrocytic Nuclear Alteration Frequencies Could Tell Us about Genotoxicity and Macrophage Iron Storage?

PubMed

Gomes, Juliana M M; Ribeiro, Heder J; Procópio, Marcela S; Alvarenga, Betânia M; Castro, Antônio C S; Dutra, Walderez O; da Silva, José B B; Corrêa Junior, José D

2015-01-01

Erythrocytic nuclear alterations have been considered as an indicative of organism's exposure to genotoxic agents. Due to their close relationship among their frequencies and DNA damages, they are considered excellent markers of exposure in eukaryotes. However, poor data has been found in literature concerning their genesis, differential occurrence and their life span. In this study, we use markers of cell viability; genotoxicity and cellular turn over in order to shed light to these events. Tilapia and their blood were exposed to cadmium in acute exposure and in vitro assays. They were analyzed using flow cytometry for oxidative stress and membrane disruption, optical microscopy for erythrocytic nuclear alteration, graphite furnace atomic absorption spectrometry for cadmium content in aquaria water, blood and cytochemical and analytical electron microscopy techniques for the hemocateretic aspects. The results showed a close relationship among the total nuclear alterations and cadmium content in the total blood and melanomacrophage centres area, mismatching reactive oxygen species and membrane damages. Moreover, nuclear alterations frequencies (vacuolated, condensed and blebbed) showed to be associated to cadmium exposure whereas others (lobed and bud) were associated to depuration period. Decrease on nuclear alterations frequencies was also associated with hemosiderin increase inside spleen and head kidney macrophages mainly during depurative processes. These data disclosure in temporal fashion the main processes that drive the nuclear alterations frequencies and their relationship with some cellular and systemic biomarkers.

Heart rate variability, hemostatic and acute inflammatory blood parameters in healthy adults after short-term exposure to welding fume.

PubMed

Scharrer, E; Hessel, H; Kronseder, A; Guth, W; Rolinski, B; Jörres, R A; Radon, K; Schierl, R; Angerer, P; Nowak, D

2007-02-01

The present study aimed to investigate, whether short-term experimental exposure to high levels of welding fumes would be capable of exerting acute effects in healthy subjects. Specifically, we assessed cardiovascular function in terms of heart rate variability (HRV) as well as the concentrations of inflammatory mediators and hemostatic proteins in blood as outcome measures. Twenty subjects without a history of airway and cardiovascular diseases were exposed to either control air or welding fume for 1 h on 2 separate days under standardized conditions. The median concentration of the alveolar particle fraction during welding was 3.5 mg/m(3 )(quartiles: 1.4-6.3 mg/m(3); range 1.0-25.3 mg/m(3)). Five hours later a panel of clinical assessments was performed, including HRV measurement and drawing of blood samples. There were no changes in symptom ratings or lung function after welding fume exposure. Exposures did also not differ regarding effects on time- and frequency-domain parameters of HRV. Similarly, blood leukocyte numbers, cell differentials and the blood levels of fibrinogen, C-reactive protein, antithrombin III, factor VIII, von Willebrand factor, ristocetin cofactor, sICAM-1, tumor necrosis factor alpha, interleukin 6, interleukin 8 and epithelial neutrophil activating peptide 78 were not altered by welding fume inhalation. However, there was a significant fall in the level of endothelin-1 (P < 0.01). In conclusion, the data did not indicate effects of clinical significance of a short-term high-level exposure to welding fumes on HRV or a set of blood hemostatic and acute inflammatory parameters in healthy subjects. The small but statistically significant effect on endothelin levels demonstrated that measurable effects could be elicited even in these individuals. Overall, welding fumes are not likely to exert acute cardiovascular effects in healthy individuals.

Acute exposure to blue wavelength light during memory consolidation improves verbal memory performance.

PubMed

Alkozei, Anna; Smith, Ryan; Dailey, Natalie S; Bajaj, Sahil; Killgore, William D S

2017-01-01

Acute exposure to light within the blue wavelengths has been shown to enhance alertness and vigilance, and lead to improved speed on reaction time tasks, possibly due to activation of the noradrenergic system. It remains unclear, however, whether the effects of blue light extend beyond simple alertness processes to also enhance other aspects of cognition, such as memory performance. The aim of this study was to investigate the effects of a thirty minute pulse of blue light versus placebo (amber light) exposure in healthy normally rested individuals in the morning during verbal memory consolidation (i.e., 1.5 hours after memory acquisition) using an abbreviated version of the California Verbal Learning Test (CVLT-II). At delayed recall, individuals who received blue light (n = 12) during the consolidation period showed significantly better long-delay verbal recall than individuals who received amber light exposure (n = 18), while controlling for the effects of general intelligence, depressive symptoms and habitual wake time. These findings extend previous work demonstrating the effect of blue light on brain activation and alertness to further demonstrate its effectiveness at facilitating better memory consolidation and subsequent retention of verbal material. Although preliminary, these findings point to a potential application of blue wavelength light to optimize memory performance in healthy populations. It remains to be determined whether blue light exposure may also enhance performance in clinical populations with memory deficits.

Sorafenib Dose Recommendation in Acute Myeloid Leukemia Based on Exposure-FLT3 Relationship.

PubMed

Liu, Tao; Ivaturi, Vijay; Sabato, Philip; Gobburu, Jogarao V S; Greer, Jacqueline M; Wright, John J; Smith, B Douglas; Pratz, Keith W; Rudek, Michelle A

2018-04-27

Sorafenib administered at the approved dose continuously is not tolerated long-term in patients with acute myeloid leukemia (AML). The purpose of this study was to optimize the dosing regimen by characterizing the sorafenib exposure-response relationship in patients with AML. A one-compartment model with a transit absorption compartment and enterohepatic recirculation described the exposure. The relationship between sorafenib exposure and target modulation of kinase targets (FMS-like tyrosine kinase 3 (FLT3)-ITD and extracellular signal-regulated kinase (ERK)) were described by an inhibitory maximum effect (E max ) model. Sorafenib could inhibit FLT3-ITD activity by 100% with an IC 50 of 69.3 ng/mL and ERK activity by 84% with an IC 50 of 85.7 ng/mL (both adjusted for metabolite potency). Different dosing regimens utilizing 200 or 400 mg at varying frequencies were simulated based on the exposure-response relationship. Simulations demonstrate that a 200 mg twice daily (b.i.d.) dosing regimen showed similar FLT3-ITD and ERK inhibitory activity compared with 400 mg b.i.d. and is recommended in further clinical trials in patients with AML. © 2018 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

REDUCING UNCERTAINTY IN AIR TOXICS RISK ASSESSMENT: A MECHANISTIC EXPOSURE-DOSE-RESPONSE (EDR) MODEL FOR ASSESSING THE ACUTE NEUROTOXICITY OF VOLATILE ORGANIC COMPOUNDS (VOCS) BASED UPON A RECEPTOR-MEDIATED MODE OF ACTION

EPA Science Inventory

SUMMARY: The major accomplishment of NTD’s air toxics program is the development of an exposure-dose- response model for acute exposure to volatile organic compounds (VOCs), based on momentary brain concentration as the dose metric associated with acute neurological impairments...

Biomarkers of acute respiratory allergen exposure: Screening for sensitization potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pucheu-Haston, Cherie M., E-mail: Pucheu-Haston.Cherie@epa.go; Copeland, Lisa B.; Vallanat, Beena

2010-04-15

Effective hazard screening will require the development of high-throughput or in vitro assays for the identification of potential sensitizers. The goal of this preliminary study was to identify potential biomarkers that differentiate the response to allergens vs non-allergens following an acute exposure in naive individuals. Female BALB/c mice received a single intratracheal aspiration exposure to Metarhizium anisopliae crude antigen (MACA) or bovine serum albumin (BSA) in Hank's Balanced Salt Solution (HBSS) or HBSS alone. Mice were terminated after 1, 3, 6, 12, 18 and 24 h. Bronchoalveolar lavage fluid (BALF) was evaluated to determine total and differential cellularity, total proteinmore » concentration and LDH activity. RNA was isolated from lung tissue for microarray analysis and qRT-PCR. MACA administration induced a rapid increase in BALF neutrophils, lymphocytes, eosinophils and total protein compared to BSA or HBSS. Microarray analysis demonstrated differential expression of genes involved in cytokine production, signaling, inflammatory cell recruitment, adhesion and activation in 3 and 12 h MACA-treated samples compared to BSA or HBSS. Further analyses allowed identification of approx 100 candidate biomarker genes. Eleven genes were selected for further assessment by qRT-PCR. Of these, 6 demonstrated persistently increased expression (Ccl17, Ccl22, Ccl7, Cxcl10, Cxcl2, Saa1), while C3ar1 increased from 6-24 h. In conclusion, a single respiratory exposure of mice to an allergenic mold extract induces an inflammatory response which is distinct in phenotype and gene transcription from the response to a control protein. Further validation of these biomarkers with additional allergens and irritants is needed. These biomarkers may facilitate improvements in screening methods.« less

In vitro acute exposure to DEHP affects oocyte meiotic maturation, energy and oxidative stress parameters in a large animal model.

PubMed

Ambruosi, Barbara; Uranio, Manuel Filioli; Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

2011-01-01

Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos

In Vitro Acute Exposure to DEHP Affects Oocyte Meiotic Maturation, Energy and Oxidative Stress Parameters in a Large Animal Model

PubMed Central

Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

2011-01-01

Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos

Use of a 15 k gene microarray to determine gene expression changes in response to acute and chronic methylmercury exposure in the fathead minnow Pimephales promelas Rafinesque

USGS Publications Warehouse

Klaper, R.; Carter, Barbara J.; Richter, C.A.; Drevnick, P.E.; Sandheinrich, M.B.; Tillitt, D.E.

2008-01-01

This study describes the use of a 15 000 gene microarray developed for the toxicological model species, Pimephales promelas, in investigating the impact of acute and chronic methylmercury exposures in male gonad and liver tissues. The results show significant differences in the individual genes that were differentially expressed in response to each treatment. In liver, a total of 650 genes exhibited significantly (P < 0.05) altered expression with greater than two-fold differences from the controls in response to acute exposure and a total of 267 genes were differentially expressed in response to chronic exposure. A majority of these genes were downregulated rather than upregulated. Fewer genes were altered in gonad than in liver at both timepoints. A total of 212 genes were differentially expressed in response to acute exposure and 155 genes were altered in response to chronic exposure. Despite the differences in individual genes expressed across treatments, the functional categories that altered genes were associated with showed some similarities. Of interest in light of other studies involving the effects of methylmercury on fish, several genes associated with apoptosis were upregulated in response to both acute and chronic exposures. Induction of apoptosis has been associated with effects on reproduction seen in the previous studies. This study demonstrates the utility of microarray analysis for investigations of the physiological effects of toxicants as well as the time-course of effects that may take place. In addition, it is the first publication to demonstrate the use of this new 15 000 gene microarray for fish biology and toxicology. ?? 2008 The Authors.

Impact of acute exposure to air pollution on the cardiorespiratory performance of military firemen.

PubMed

Oliveira, R S; Barros Neto, T L; Braga, A L F; Raso, V; Pereira, L A A; Morette, S R; Carneiro, R C

2006-12-01

The objective of the present study was to determine the impact of acute short-term exposure to air pollution on the cardiorespiratory performance of military firemen living and working in the city of Guarujá, São Paulo, Brazil. Twenty-five healthy non-smoking firemen aged 24 to 45 years had about 1 h of exposure to low and high levels of air pollution. The tests consisted of two phases: phase A, in Bertioga, a town with low levels of air pollution, and phase B, in Cubatão, a polluted town, with a 7-day interval between phases. The volunteers remained in the cities (Bertioga/Cubatão) only for the time required to perform the tests. Cumulative load 10 +/- 2 min-long exertion tests were performed on a treadmill, consisting of a 2-min stage at a load of 7 km/h, followed by increasing exertion of 1 km h-1 min-1 until the maximum individual limit. There were statistically significant differences (P < 0.05) in anaerobic threshold (AT) between Cubatão (35.04 +/- 4.91 mL kg-1 min-1) and Bertioga (36.98 +/- 5.62 mL kg-1 min-1; P = 0.01), in the heart rate at AT (AT HR; Cubatão 152.08 +/- 14.86 bpm, Bertioga 157.44 +/- 13.64 bpm; P = 0.001), and in percent maximal oxygen consumption at AT (AT%VO2max; Cubatão 64.56 +/- 6.55%, Bertioga 67.40 +/- 5.35%; P = 0.03). However, there were no differences in VO2max, maximal heart rate or velocity at AT (ATvel) observed in firemen between towns. The acute exposure to pollutants in Cubatão, SP, caused a significant reduction in the performance at submaximal levels of physical exertion.

Acute Exposure to Stress Improves Performance in Trace Eyeblink Conditioning and Spatial Learning Tasks in Healthy Men

ERIC Educational Resources Information Center

Duncko, Roman; Cornwell, Brian; Cui, Lihong; Merikangas, Kathleen R.; Grillon, Christian

2007-01-01

The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure,…

Integrating workplace exposure databases for occupational medicine services and epidemiologic studies at a former nuclear weapons facility.

PubMed

Ruttenber, A J; McCrea, J S; Wade, T D; Schonbeck, M F; LaMontagne, A D; Van Dyke, M V; Martyny, J W

2001-02-01

We outline methods for integrating epidemiologic and industrial hygiene data systems for the purpose of exposure estimation, exposure surveillance, worker notification, and occupational medicine practice. We present examples of these methods from our work at the Rocky Flats Plant--a former nuclear weapons facility that fabricated plutonium triggers for nuclear weapons and is now being decontaminated and decommissioned. The weapons production processes exposed workers to plutonium, gamma photons, neutrons, beryllium, asbestos, and several hazardous chemical agents, including chlorinated hydrocarbons and heavy metals. We developed a job exposure matrix (JEM) for estimating exposures to 10 chemical agents in 20 buildings for 120 different job categories over a production history spanning 34 years. With the JEM, we estimated lifetime chemical exposures for about 12,000 of the 16,000 former production workers. We show how the JEM database is used to estimate cumulative exposures over different time periods for epidemiological studies and to provide notification and determine eligibility for a medical screening program developed for former workers. We designed an industrial hygiene data system for maintaining exposure data for current cleanup workers. We describe how this system can be used for exposure surveillance and linked with the JEM and databases on radiation doses to develop lifetime exposure histories and to determine appropriate medical monitoring tests for current cleanup workers. We also present time-line-based graphical methods for reviewing and correcting exposure estimates and reporting them to individual workers.

Does acute radio-frequency electromagnetic field exposure affect visual event-related potentials in healthy adults?

PubMed

Dalecki, Anna; Loughran, Sarah P; Verrender, Adam; Burdon, Catriona A; Taylor, Nigel A S; Croft, Rodney J

2018-05-01

To use improved methods to address the question of whether acute exposure to radio-frequency (RF) electromagnetic fields (RF-EMF) affects early (80-200 ms) sensory and later (180-600 ms) cognitive processes as indexed by event-related potentials (ERPs). Thirty-six healthy subjects completed a visual discrimination task during concurrent exposure to a Global System for Mobile Communications (GSM)-like, 920 MHz signal with peak-spatial specific absorption rate for 10 g of tissue of 0 W/kg of body mass (Sham), 1 W/kg (Low RF) and 2 W/kg (High RF). A fully randomised, counterbalanced, double-blind design was used. P1 amplitude was reduced (p = .02) and anterior N1 latency was increased (p = .04) during Exposure compared to Sham. There were no effects on any other ERP latencies or amplitudes. RF-EMF exposure may affect early perceptual (P1) and preparatory motor (anterior N1) processes. However, only two ERP indices, out of 56 comparisons, were observed to differ between RF-EMF exposure and Sham, suggesting that these observations may be due to chance. These observations are consistent with previous findings that RF-EMF exposure has no reliable impact on cognition (e.g., accuracy and response speed). Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Acute and recent air pollution exposure and cardiovascular events at labour and delivery

PubMed Central

Männistö, Tuija; Mendola, Pauline; Grantz, Katherine Laughon; Leishear, Kira; Sundaram, Rajeshwari; Sherman, Seth; Ying, Qi; Liu, Danping

2017-01-01

Objective To study the relationship between acute air pollution exposure and cardiovascular events during labour/delivery. Methods The Consortium on Safe Labor (2002–2008), an observational US cohort with 223 502 singleton deliveries provided electronic medical records. Air pollution exposure was estimated by modified Community Multiscale Air Quality models. Cardiovascular events (cardiac failure/arrest, stroke, myocardial infarcts and other events) were recorded in the hospital discharge records for 687 pregnancies (0.3%). Logistic regression with generalised estimating equations estimated the relationship between cardiovascular events and daily air pollutant levels for delivery day and the 7 days preceding delivery. Results Increased odds of cardiovascular events were observed for each IQR increase in exposure to nitric oxides at 5 and 6 days prior to delivery (OR=1.17, 99% CI 1.04 to 1.30 and OR=1.15, 1.03 to 1.28, respectively). High exposure to toxic air pollution species such as ethylbenzene (OR=1.50, 1.08 to 2.09), m-xylene (OR=1.54, 1.11 to 2.13), o-xylene (OR=1.51, 1.09 to 2.09), p-xylene (OR=1.43, 1.03 to 1.99) and toluene (OR=1.42, 1.02 to 1.97) at 5 days prior to delivery were also associated with cardiovascular events. Decreased odds of events were observed with exposure to ozone. Conclusions Air pollution in the days prior to delivery, especially nitrogen oxides and some toxic air pollution species, was associated with increased risk of cardiovascular events during the labour/delivery admission. PMID:26105036

Perceived Chronic Stress Exposure Modulates Reward-Related Medial Prefrontal Cortex Responses to Acute Stress in Depression

PubMed Central

Kumar, Poornima; Slavich, George M.; Berghorst, Lisa H.; Treadway, Michael T.; Brooks, Nancy H.; Dutra, Sunny J.; Greve, Douglas N.; O'Donovan, Aoife; Bleil, Maria E.; Maninger, Nicole; Pizzagalli, Diego A.

2015-01-01

Introduction Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. Methods In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Results Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r = 0.79, p = 0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r = 0.79) and no-stress (r = −0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC grey matter, but functional findings remained when accounting for structural differences. Limitation Small sample size, which warrants replication. Conclusion Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. PMID:25898329

Short-term and persistent impacts on behaviors related to locomotion, anxiety, and startle responses of Japanese medaka (Oryzias latipes) induced by acute, sublethal exposure to chlorpyrifos.

PubMed

Qiu, Xuchun; Nomichi, Sayaka; Chen, Kun; Honda, Masato; Kang, Ik Joon; Shimasaki, Yohei; Oshima, Yuji

2017-11-01

Although most exposures to chlorpyrifos (CPF) in natural flowing waters are brief and episodic, there have been a few reports of the persistence of abnormal fish behaviors caused by such acute exposure. The present study focused on the behavioral and biochemical responses of Japanese medaka (Oryzias latipes) to acute, sublethal exposure to CPF, as well as the persistence of the effects during a 3-week recovery test in CPF-free water. The medaka became hyperactive and exhibited an elevated anxiety state after a 4-day exposure to 0.024mg/L of CPF, but they recovered from these abnormal behavioral responses within 7days of recovery treatment. In contrast, persistent impacts on some startle responses to a sudden stimulation (induced by a ball drop) were observed in medaka exposed to CPF. The reaction latency did not change immediately after the 4-day exposure, but was significantly prolonged by as much as 21days after the termination of exposure. The post-stimulus swimming distance within 5s significantly decreased on the day immediately after the 4-day exposure, but it significantly increased after 7days of recovery treatment. The activity of acetylcholinesterase (AChE) in the brains of medaka was significantly inhibited on the day immediately after the 4-day exposure, but it returned to 80% and 110% of that in control fish on days 7 and 21 of the recovery period, respectively. However, AChE activities in the eyes of exposed medaka were persistently inhibited and declined to 33%, 71%, and 72% of that in control fish on days 0 (immediately after the 4-day exposure), 7, and 21 of recovery, respectively. Correlation analysis suggested that the changes of AChE activities in the brains of medaka may underlie some of the observed acute behavioral changes, and the changes of AChE activities in the eyes may contribute to the persistence of the abnormalities in the reaction latency of the startle response. Our findings suggest that medaka need a long time to recover from acute

Acute Lymphocytic Leukemia

MedlinePlus

... radiation. People exposed to very high levels of radiation, such as survivors of a nuclear reactor accident, have an increased risk of developing acute lymphocytic leukemia. Genetic disorders. Certain genetic disorders, such as Down syndrome, are associated with an increased risk of acute ...

EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS

EPA Science Inventory

EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN OLD SPONTANEOUSLY HYPERTENSIVE RATS. JP Nolan1, LB Wichers2, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, DL Costa1, and WP Watkinson1. 1US E...

QSAR Modeling of Rat Acute Toxicity by Oral Exposure

PubMed Central

Zhu, Hao; Martin, Todd M.; Ye, Lin; Sedykh, Alexander; Young, Douglas M.; Tropsha, Alexander

2009-01-01

Few Quantitative Structure-Activity Relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity endpoints. In this study, a comprehensive dataset of 7,385 compounds with their most conservative lethal dose (LD50) values has been compiled. A combinatorial QSAR approach has been employed to develop robust and predictive models of acute toxicity in rats caused by oral exposure to chemicals. To enable fair comparison between the predictive power of models generated in this study versus a commercial toxicity predictor, TOPKAT (Toxicity Prediction by Komputer Assisted Technology), a modeling subset of the entire dataset was selected that included all 3,472 compounds used in the TOPKAT’s training set. The remaining 3,913 compounds, which were not present in the TOPKAT training set, were used as the external validation set. QSAR models of five different types were developed for the modeling set. The prediction accuracy for the external validation set was estimated by determination coefficient R2 of linear regression between actual and predicted LD50 values. The use of the applicability domain threshold implemented in most models generally improved the external prediction accuracy but expectedly led to the decrease in chemical space coverage; depending on the applicability domain threshold, R2 ranged from 0.24 to 0.70. Ultimately, several consensus models were developed by averaging the predicted LD50 for every compound using all 5 models. The consensus models afforded higher prediction accuracy for the external validation dataset with the higher coverage as compared to individual constituent models. The validated consensus LD50 models developed in this study can be used as reliable computational predictors of in vivo acute toxicity. PMID:19845371

Acute exposure to air pollution triggers atrial fibrillation.

PubMed

Link, Mark S; Luttmann-Gibson, Heike; Schwartz, Joel; Mittleman, Murray A; Wessler, Benjamin; Gold, Diane R; Dockery, Douglas W; Laden, Francine

2013-08-27

This study sought to evaluate the association of air pollution with the onset of atrial fibrillation (AF). Air pollution in general and more specifically particulate matter has been associated with cardiovascular events. Although ventricular arrhythmias are traditionally thought to convey the increased cardiovascular risk, AF may also contribute. Patients with dual chamber implantable cardioverter-defibrillators (ICDs) were enrolled and followed prospectively. The association of AF onset with air quality including ambient particulate matter <2.5 μm aerodynamic diameter (PM2.5), black carbon, sulfate, particle number, NO2, SO2, and O3 in the 24 h prior to the arrhythmia was examined utilizing a case-crossover analysis. In sensitivity analyses, associations with air pollution between 2 and 48 h prior to the AF were examined. Of 176 patients followed for an average of 1.9 years, 49 patients had 328 episodes of AF lasting ≥ 30 s. Positive but nonsignificant associations were found for PM2.5 in the prior 24 h, but stronger associations were found with shorter exposure windows. The odds of AF increased by 26% (95% confidence interval: 8% to 47%) for each 6.0 μg/m(3) increase in PM2.5 in the 2 h prior to the event (p = 0.004). The odds of AF were highest at the upper quartile of mean PM2.5. PM was associated with increased odds of AF onset within hours following exposure in patients with known cardiac disease. Air pollution is an acute trigger of AF, likely contributing to the pollution-associated adverse cardiac outcomes observed in epidemiological studies. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Non-cancer effects in acute radiation syndrome survivors in Ukraine.

PubMed

Belyi, David; Kovalenko, Aleksander; Bazyka, Dmitrij; Bebeshko, Vladimir

2010-06-01

The 1986 Chernobyl Nuclear Power Plant accident that occurred is known as the most severe nuclear disaster in the history of humankind. Acute radiation syndrome (ARS) was diagnosed in 237 persons but only 134 of those were confirmed, including 28 patients who died due to lethal total-body gamma-irradiation and severe skin injuries caused by beta/gamma-emitting radionuclides. A small group of ARS survivors offers an interesting observational insight pertinent to the on-going discussions about long-term non-cancer effects of ionizing radiation. This descriptive study summarizes more than 20 y of follow-up, makes attempts to offer a prognosis for the Chernobyl ARS survivors' health, and explores the link between the outcomes of interest and radiation exposure.

Exposure to Discrimination and Heart Rate Variability Reactivity to Acute Stress among Women with Diabetes.

PubMed

Wagner, Julie; Lampert, Rachel; Tennen, Howard; Feinn, Richard

2015-08-01

Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. Copyright © 2013 John Wiley & Sons, Ltd.

Non-malignant thyroid disease after exposure to radioactive elements during nuclear explosion: a neglected issue.

PubMed

Wiwanitkit, Viroj

2012-01-01

Recent nuclear explosion in Japan led to a great concern regarding its detrimental effects on health. As obtained data imply the increased risk of thyroid cancer, the prevention is widely suggested. Also the adverse effect of leaked radioactive elements can lead to non-malignant thyroid disease, which is neglected. In this article, non-malignant thyroid disease after exposure to radioactive elements during nuclear explosion was reviewed and discussed.

Cytoplasmic proliferating cell nuclear antigen connects glycolysis and cell survival in acute myeloid leukemia.

PubMed

Ohayon, Delphine; De Chiara, Alessia; Chapuis, Nicolas; Candalh, Céline; Mocek, Julie; Ribeil, Jean-Antoine; Haddaoui, Lamya; Ifrah, Norbert; Hermine, Olivier; Bouillaud, Frédéric; Frachet, Philippe; Bouscary, Didier; Witko-Sarsat, Véronique

2016-10-19

Cytosolic proliferating cell nuclear antigen (PCNA), a scaffolding protein involved in DNA replication, has been described as a key element in survival of mature neutrophil granulocytes, which are non-proliferating cells. Herein, we demonstrated an active export of PCNA involved in cell survival and chemotherapy resistance. Notably, daunorubicin-resistant HL-60 cells (HL-60R) have a prominent cytosolic PCNA localization due to increased nuclear export compared to daunorubicin-sensitive HL-60 cells (HL-60S). By interacting with nicotinamide phosphoribosyltransferase (NAMPT), a protein involved in NAD biosynthesis, PCNA coordinates glycolysis and survival, especially in HL-60R cells. These cells showed a dramatic increase in intracellular NAD+ concentration as well as glycolysis including increased expression and activity of hexokinase 1 and increased lactate production. Furthermore, this functional activity of cytoplasmic PCNA was also demonstrated in patients with acute myeloid leukemia (AML). Our data uncover a novel pathway of nuclear export of PCNA that drives cell survival by increasing metabolism flux.

Cytoplasmic proliferating cell nuclear antigen connects glycolysis and cell survival in acute myeloid leukemia

PubMed Central

Ohayon, Delphine; De Chiara, Alessia; Chapuis, Nicolas; Candalh, Céline; Mocek, Julie; Ribeil, Jean-Antoine; Haddaoui, Lamya; Ifrah, Norbert; Hermine, Olivier; Bouillaud, Frédéric; Frachet, Philippe; Bouscary, Didier; Witko-Sarsat, Véronique

2016-01-01

Cytosolic proliferating cell nuclear antigen (PCNA), a scaffolding protein involved in DNA replication, has been described as a key element in survival of mature neutrophil granulocytes, which are non-proliferating cells. Herein, we demonstrated an active export of PCNA involved in cell survival and chemotherapy resistance. Notably, daunorubicin-resistant HL-60 cells (HL-60R) have a prominent cytosolic PCNA localization due to increased nuclear export compared to daunorubicin-sensitive HL-60 cells (HL-60S). By interacting with nicotinamide phosphoribosyltransferase (NAMPT), a protein involved in NAD biosynthesis, PCNA coordinates glycolysis and survival, especially in HL-60R cells. These cells showed a dramatic increase in intracellular NAD+ concentration as well as glycolysis including increased expression and activity of hexokinase 1 and increased lactate production. Furthermore, this functional activity of cytoplasmic PCNA was also demonstrated in patients with acute myeloid leukemia (AML). Our data uncover a novel pathway of nuclear export of PCNA that drives cell survival by increasing metabolism flux. PMID:27759041

Analysis of Dextromethorphan and Dextrorphan in Skeletal Remains Following Differential Microclimate Exposure: Comparison of Acute vs. Repeated Drug Exposure.

PubMed

Morrison, Lucas M; Unger, Kirk A; Watterson, James H

2017-07-01

Analysis of dextromethorphan (DXM) and its metabolite dextrorphan (DXT) in skeletal remains of rats following acute (ACU, 75 mg/kg, IP, n = 10) or three repeated (REP, 25 mg/kg, IP, n = 10, 40-min interval) doses of DXM is described. Following dosing and euthanasia, rats decomposed outdoors to skeleton in two different microclimate environments (n = 5 ACU and n = 5 REP at each site): Site A (shaded forest microenvironment) and Site B (rocky substrate exposed to direct sunlight, 600 m from Site A). Two drug-free rats at each site served as negative controls. Skeletal elements (vertebrae, ribs, pelvic girdles, femora, tibiae, skulls and scapulae) were recovered, pulverized and underwent methanolic microwave assisted extraction (MAE). Extracts were analyzed by GC-MS following clean-up by solid-phase extraction (SPE). Drug levels, expressed as mass-normalized response ratios and the ratios of DXT and DXM levels (RRDXT/RRDXM) were compared between drug exposures, microclimate sites, and across skeletal elements. DXM levels differed significantly (P < 0.05) between corresponding bone elements across exposure groups (5/7-site A; 4/7-site B), but no significant differences in DXT levels were observed between corresponding elements. RRDXT/RRDXM differed significantly (P < 0.05) between corresponding bone elements across exposure groups (6/7-site A; 5/7-site B). No significant differences were observed in levels of DXM, DXT or RRDXT/RRDXM between corresponding elements from either group between sites. When data from all bone elements was pooled, levels of DXM and RRDXT/RRDXM differed significantly between exposure groups at each site, while those of DXT did not. For both exposure groups, comparison of pooled data between sites showed no significant differences in levels of DXM, DXT or RRDXT/RRDXM. Different decomposition microclimates did not impede the discrimination of DXM exposure patterns from the analyses of DXM, DXT and RRDXT/RRDXM in bone samples. © The Author 2017

The Difference between Anxiolytic and Anxiogenic Effects Induced by Acute and Chronic Alcohol Exposure and Changes in Associative Learning and Memory Based on Color Preference and the Cause of Parkinson-Like Behaviors in Zebrafish.

PubMed

Li, Xiang; Li, Xu; Li, Yi-Xiang; Zhang, Yuan; Chen, Di; Sun, Ming-Zhu; Zhao, Xin; Chen, Dong-Yan; Feng, Xi-Zeng

2015-01-01

We describe an interdisciplinary comparison of the effects of acute and chronic alcohol exposure in terms of their disturbance of light, dark and color preferences and the occurrence of Parkinson-like behavior in zebrafish through computer visual tracking, data mining, and behavioral and physiological analyses. We found that zebrafish in anxiolytic and anxious states, which are induced by acute and chronic repeated alcohol exposure, respectively, display distinct emotional reactions in light/dark preference tests as well as distinct learning and memory abilities in color-enhanced conditional place preference (CPP) tests. Additionally, compared with the chronic alcohol (1.0%) treatment, acute alcohol exposure had a significant, dose-dependent effect on anxiety, learning and memory (color preference) as well as locomotive activities. Acute exposure doses (0.5%, 1.0%, and 1.5%) generated an "inverted V" dose-dependent pattern in all of the behavioral parameters, with 1.0% having the greatest effect, while the chronic treatment had a moderate effect. Furthermore, by measuring locomotive activity, learning and memory performance, the number of dopaminergic neurons, tyrosine hydroxylase expression, and the change in the photoreceptors in the retina, we found that acute and chronic alcohol exposure induced varying degrees of Parkinson-like symptoms in zebrafish. Taken together, these results illuminated the behavioral and physiological mechanisms underlying the changes associated with learning and memory and the cause of potential Parkinson-like behaviors in zebrafish due to acute and chronic alcohol exposure.

The Difference between Anxiolytic and Anxiogenic Effects Induced by Acute and Chronic Alcohol Exposure and Changes in Associative Learning and Memory Based on Color Preference and the Cause of Parkinson-Like Behaviors in Zebrafish

PubMed Central

Zhang, Yuan; Chen, Di; Sun, Ming-Zhu; Zhao, Xin; Chen, Dong-Yan; Feng, Xi-Zeng

2015-01-01

We describe an interdisciplinary comparison of the effects of acute and chronic alcohol exposure in terms of their disturbance of light, dark and color preferences and the occurrence of Parkinson-like behavior in zebrafish through computer visual tracking, data mining, and behavioral and physiological analyses. We found that zebrafish in anxiolytic and anxious states, which are induced by acute and chronic repeated alcohol exposure, respectively, display distinct emotional reactions in light/dark preference tests as well as distinct learning and memory abilities in color-enhanced conditional place preference (CPP) tests. Additionally, compared with the chronic alcohol (1.0%) treatment, acute alcohol exposure had a significant, dose-dependent effect on anxiety, learning and memory (color preference) as well as locomotive activities. Acute exposure doses (0.5%, 1.0%, and 1.5%) generated an “inverted V” dose-dependent pattern in all of the behavioral parameters, with 1.0% having the greatest effect, while the chronic treatment had a moderate effect. Furthermore, by measuring locomotive activity, learning and memory performance, the number of dopaminergic neurons, tyrosine hydroxylase expression, and the change in the photoreceptors in the retina, we found that acute and chronic alcohol exposure induced varying degrees of Parkinson-like symptoms in zebrafish. Taken together, these results illuminated the behavioral and physiological mechanisms underlying the changes associated with learning and memory and the cause of potential Parkinson-like behaviors in zebrafish due to acute and chronic alcohol exposure. PMID:26558894

Acute nonhypothermic exposure to cold impedes motor skill performance in video gaming compared to thermo-neutral and hot conditions.

PubMed

Edwards, Andrew M; Crowther, Robert G; Morton, R Hugh; Polman, Remco C

2011-02-01

The study examined whether or not acute exposure to unfamiliar hot or cold conditions impairs performance of highly skilled coordinative activities and whether prior physical self-efficacy beliefs were associated with task completion. Nineteen volunteers completed both Guitar Hero and Archery activities as a test battery using the Nintendo Wii console in cold (2 degrees C), neutral (20 degrees C), and hot (38 degrees C) conditions. Participants all completed physical self-efficacy questionnaires following experimental familiarization. Performances of both Guitar Hero and Archery significantly decreased in the cold compared with the neutral condition. The cold trial was also perceived as the condition requiring both greater concentration and effort. There was no association between performance and physical self-efficacy. Performance of these coordinative tasks was compromised by acute (nonhypothermic) exposure to cold; the most likely explanation is that the cold condition presented a greater challenge to attentional processes as a form of environmental distraction.

Elemental carbon exposure at residence and survival after acute myocardial infarction.

PubMed

von Klot, Stephanie; Gryparis, Alexandros; Tonne, Cathryn; Yanosky, Jeffrey; Coull, Brent A; Goldberg, Robert J; Lessard, Darleen; Melly, Steven J; Suh, Helen H; Schwartz, Joel

2009-07-01

Particulate air pollution has been consistently related to cardiovascular mortality. Some evidence suggests that particulate matter may accelerate the atherosclerotic process. Effects of within-city variations of particulate air pollution on survival after an acute cardiovascular event have been little explored. We conducted a cohort study of hospital survivors of acute myocardial infarction (MI) from the Worcester, MA, metropolitan area to investigate the long-term effects of within-city variation in traffic-related air pollution on mortality. The study builds on an ongoing community-wide investigation examining changes over time in MI incidence and case-fatality rates. We included confirmed cases of MI in 1995, 1997, 1999, 2001, and 2003. Long-term survival status was ascertained through 2005. A validated spatiotemporal land use regression model for traffic-related air pollution was developed and annual averages of elemental carbon at residence estimated. The effect of estimated elemental carbon on the long-term mortality of patients discharged after MI was analyzed using a Cox proportional hazards model, controlling for a variety of demographic, medical history, and clinical variables. Of the 3895 patients with validated MI, 44% died during follow-up. Exposure to estimated elemental carbon in the year of entry into the study was 0.44 microg/m on average. All-cause mortality increased by 15% (95% confidence interval = 0.03%-29%) per interquartile range increase in estimated yearly elemental carbon (0.24 microg/m) after the second year of survival. No association between traffic-related pollution and all-cause mortality was observed during the first 2 years of follow-up. Chronic traffic-related particulate air pollution is associated with increased mortality in hospital survivors of acute MI after the second year of survival.

Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival

PubMed Central

Quintens, Roel; Samari, Nada; de Saint-Georges, Louis; van Oostveldt, Patrick; Baatout, Sarah; Benotmane, Mohammed Abderrafi

2016-01-01

During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight. PMID:27203085

What the Erythrocytic Nuclear Alteration Frequencies Could Tell Us about Genotoxicity and Macrophage Iron Storage?

PubMed Central

Gomes, Juliana M. M.; Ribeiro, Heder J.; Procópio, Marcela S.; Alvarenga, Betânia M.; Castro, Antônio C. S.; Dutra, Walderez O.; da Silva, José B. B.; Corrêa Junior, José D.

2015-01-01

Erythrocytic nuclear alterations have been considered as an indicative of organism’s exposure to genotoxic agents. Due to their close relationship among their frequencies and DNA damages, they are considered excellent markers of exposure in eukaryotes. However, poor data has been found in literature concerning their genesis, differential occurrence and their life span. In this study, we use markers of cell viability; genotoxicity and cellular turn over in order to shed light to these events. Tilapia and their blood were exposed to cadmium in acute exposure and in vitro assays. They were analyzed using flow cytometry for oxidative stress and membrane disruption, optical microscopy for erythrocytic nuclear alteration, graphite furnace atomic absorption spectrometry for cadmium content in aquaria water, blood and cytochemical and analytical electron microscopy techniques for the hemocateretic aspects. The results showed a close relationship among the total nuclear alterations and cadmium content in the total blood and melanomacrophage centres area, mismatching reactive oxygen species and membrane damages. Moreover, nuclear alterations frequencies (vacuolated, condensed and blebbed) showed to be associated to cadmium exposure whereas others (lobed and bud) were associated to depuration period. Decrease on nuclear alterations frequencies was also associated with hemosiderin increase inside spleen and head kidney macrophages mainly during depurative processes. These data disclosure in temporal fashion the main processes that drive the nuclear alterations frequencies and their relationship with some cellular and systemic biomarkers. PMID:26619141

The effect of acute exposure to hyperbaric oxygen on respiratory system mechanics in the rat.

PubMed

Rubini, Alessandro; Porzionato, Andrea; Zara, Susi; Cataldi, Amelia; Garetto, Giacomo; Bosco, Gerardo

2013-10-01

This study was designed to investigate the possible effects of acute hyperbaric hyperoxia on respiratory mechanics of anaesthetised, positive-pressure ventilated rats. We measured respiratory mechanics by the end-inflation occlusion method in nine rats previously acutely exposed to hyperbaric hyperoxia in a standard fashion. The method allows the measurements of respiratory system elastance and of both the "ohmic" and of the viscoelastic components of airway resistance, which respectively depend on the newtonian pressure dissipation due to the ohmic airway resistance to air flow, and on the viscoelastic pressure dissipation caused by respiratory system tissues stress-relaxation. The activities of inducible and endothelial NO-synthase in the lung's tissues (iNOS and eNOS respectively) also were investigated. Data were compared with those obtained in control animals. We found that the exposure to hyperbaric hyperoxia increased respiratory system elastance and both the "ohmic" and viscoelastic components of inspiratory resistances. These changes were accompanied by increased iNOS but not eNOS activities. Hyperbaric hyperoxia was shown to acutely induce detrimental effects on respiratory mechanics. A possible causative role was suggested for increased nitrogen reactive species production because of increased iNOS activity.

Interaction of acute-phase-inducible and liver-enriched nuclear factors with the promoter region of the mouse alpha sub 1 -acid glycoprotein gene-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alam, T.; Papaconstantinou, J.

1992-02-25

The synthesis and secretion of several acute-phase proteins increases markedly following physiological stress. {alpha}{sub 1}-Acid glycoprotein (AGP), a major acute-phase reactant made by the liver, is strongly induced by inflammatory agents such as lipopolysaccharide (LPS). Nuclear run-on assay showed a 17-fold increase in the rate of AGP transcription 4 h following LPS injection. DNase I footprinting assays revealed multiple protein binding domains in the mouse AGP-1 promoter region. Region B ({minus}104 to {minus}91) is protected by a liver-enriched transcription factor that is heat labile and in limiting quantity. An adjacent region, C ({minus}125 to {minus}104), is well-protected by nuclear extractsmore » from hepatocytes. Electrophoretic mobility shift assays indicated that only one DNA-protein complex can form with an oligonucleotide corresponding to region B. However, nuclear proteins from untreated mouse liver can form three strong complexes (C1, C2, and C3) and a weak one (C4) with oligonucleotide C. An acute-phase-inducible DNA-binding protein (AP-DBP) forms complex 4. A dramatic increase (over 11-fold) in AP-DBP binding activity is seen with nuclear proteins from LPS-stimulated animals. Interestingly, AP-DBP, a heat-stable factor, can form heterodimers with the transcription factor CCAAT/enhancer binding protein (C/EBP). Furthermore, purified C/EBP also binds avidly to region C. The studies indicate that several liver-enriched nuclear factors can interact with AGP-1 promoter and that AP-DBP binds to the AGP-1 promoter with high affinity only during the acute-phase induction.« less

Release of Severe Acute Respiratory Syndrome Coronavirus Nuclear Import Block Enhances Host Transcription in Human Lung Cells

PubMed Central

Tilton, Susan C.; Menachery, Vineet D.; Gralinski, Lisa E.; Schäfer, Alexandra; Matzke, Melissa M.; Webb-Robertson, Bobbie-Jo M.; Chang, Jean; Luna, Maria L.; Long, Casey E.; Shukla, Anil K.; Bankhead, Armand R.; Burkett, Susan E.; Zornetzer, Gregory; Tseng, Chien-Te Kent; Metz, Thomas O.; Pickles, Raymond; McWeeney, Shannon; Smith, Richard D.; Katze, Michael G.; Waters, Katrina M.; Baric, Ralph S.

2013-01-01

The severe acute respiratory syndrome coronavirus accessory protein ORF6 antagonizes interferon signaling by blocking karyopherin-mediated nuclear import processes. Viral nuclear import antagonists, expressed by several highly pathogenic RNA viruses, likely mediate pleiotropic effects on host gene expression, presumably interfering with transcription factors, cytokines, hormones, and/or signaling cascades that occur in response to infection. By bioinformatic and systems biology approaches, we evaluated the impact of nuclear import antagonism on host expression networks by using human lung epithelial cells infected with either wild-type virus or a mutant that does not express ORF6 protein. Microarray analysis revealed significant changes in differential gene expression, with approximately twice as many upregulated genes in the mutant virus samples by 48 h postinfection, despite identical viral titers. Our data demonstrated that ORF6 protein expression attenuates the activity of numerous karyopherin-dependent host transcription factors (VDR, CREB1, SMAD4, p53, EpasI, and Oct3/4) that are critical for establishing antiviral responses and regulating key host responses during virus infection. Results were confirmed by proteomic and chromatin immunoprecipitation assay analyses and in parallel microarray studies using infected primary human airway epithelial cell cultures. The data strongly support the hypothesis that viral antagonists of nuclear import actively manipulate host responses in specific hierarchical patterns, contributing to the viral pathogenic potential in vivo. Importantly, these studies and modeling approaches not only provide templates for evaluating virus antagonism of nuclear import processes but also can reveal candidate cellular genes and pathways that may significantly influence disease outcomes following severe acute respiratory syndrome coronavirus infection in vivo. PMID:23365422

Evaluation and management of patients in the acute phase of myocardial infarction - the role of nuclear medicine in the coronary care unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palac, R.T.; Gray, L.; Brown, P.H.

1988-09-01

This is the third article in a four-part continuing education series relating to patient care and management. After completing the article, the reader should be able to: 1) understand the application, potential, and problems of nuclear cardiology in the coronary care unit; 2) recognize the utilization of nuclear cardiology in acute coronary care management; and 3) appreciate the important role of nuclear cardiology in cardiac patient care.

Acute liver failure in neonates with undiagnosed hereditary fructose intolerance due to exposure from widely available infant formulas.

PubMed

Li, Hong; Byers, Heather M; Diaz-Kuan, Alicia; Vos, Miriam B; Hall, Patricia L; Tortorelli, Silvia; Singh, Rani; Wallenstein, Matthew B; Allain, Meredith; Dimmock, David P; Farrell, Ryan M; McCandless, Shawn; Gambello, Michael J

2018-04-01

Hereditary fructose intolerance (HFI) is an autosomal recessive disorder caused by aldolase B (ALDOB) deficiency resulting in an inability to metabolize fructose. The toxic accumulation of intermediate fructose-1-phosphate causes multiple metabolic disturbances, including postprandial hypoglycemia, lactic acidosis, electrolyte disturbance, and liver/kidney dysfunction. The clinical presentation varies depending on the age of exposure and the load of fructose. Some common infant formulas contain fructose in various forms, such as sucrose, a disaccharide of fructose and glucose. Exposure to formula containing fructogenic compounds is an important, but often overlooked trigger for severe metabolic disturbances in HFI. Here we report four neonates with undiagnosed HFI, all caused by the common, homozygous mutation c.448G>C (p.A150P) in ALDOB, who developed life-threatening acute liver failure due to fructose-containing formulas. These cases underscore the importance of dietary history and consideration of HFI in cases of neonatal or infantile acute liver failure for prompt diagnosis and treatment of HFI. Copyright © 2018 Elsevier Inc. All rights reserved.

Perceived life stress exposure modulates reward-related medial prefrontal cortex responses to acute stress in depression.

PubMed

Kumar, Poornima; Slavich, George M; Berghorst, Lisa H; Treadway, Michael T; Brooks, Nancy H; Dutra, Sunny J; Greve, Douglas N; O'Donovan, Aoife; Bleil, Maria E; Maninger, Nicole; Pizzagalli, Diego A

2015-07-15

Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r=0.79, p=0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r=0.79) and no-stress (r=-0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC gray matter, but functional findings remained robust while accounting for structural differences. Small sample size, which warrants replication. Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. Copyright © 2015 Elsevier B.V. All rights reserved.

Transcriptional profiling of primary endometrial epithelial cells following acute HIV-1 exposure reveals gene signatures related to innate immunity.

PubMed

Zahoor, Muhammad Atif; Woods, Matthew William; Dizzell, Sara; Nazli, Aisha; Mueller, Kristen M; Nguyen, Philip V; Verschoor, Chris P; Kaushic, Charu

2018-04-01

Genital epithelial cells (GECs) line the mucosal surface of the female genital tract (FGT) and are the first cells that interface with both commensal microbiota and sexually transmitted pathogens. Despite the protective barrier formed by GECs, the FGT is a major site of HIV-1 infection. This highlights the importance of studying the interaction of HIV-1 and GECs. Using microarray analysis, we characterized the transcriptional profile of primary endometrial GECs grown in the presence or absence of physiological levels of E2 (10 -9  mol/L) or P4 (10 -7  mol/L) following acute exposure to HIV-1 for 6 hours. Acute exposure of primary endometrial GECs to HIV-1 resulted in the expression of genes related to inflammation, plasminogen activation, adhesion and diapedesis and interferon response. Interestingly, exposure to HIV-1 in the presence of E2 and P4 resulted in differential transcriptional profiles, suggesting that the response of primary endometrial GECs to HIV-1 exposure is modulated by female sex hormones. The gene expression signature of endometrial GECs indicates that the response of these cells may be key to determining host susceptibility to HIV-1 and that sex hormones modulate these interactions. This study allows us to explore possible mechanisms that explain the hormone-mediated fluctuation of HIV-1 susceptibility in women. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Quantifying fish swimming behavior in response to acute exposure of aqueous copper using computer assisted video and digital image analysis

USGS Publications Warehouse

Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

2016-01-01

Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors.

Quantifying Fish Swimming Behavior in Response to Acute Exposure of Aqueous Copper Using Computer Assisted Video and Digital Image Analysis

PubMed Central

Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

2016-01-01

Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors. PMID:26967350

Decontamination work in the area surrounding Fukushima Dai-ichi Nuclear Power Plant: another occupational health challenge of the nuclear disaster.

PubMed

Wada, Koji; Yoshikawa, Toru; Murata, Masaru

2012-01-01

This article describes occupational health measures for workers involved in decontamination of radioactive material discharged around Fukushima Dai-ichi Nuclear Power Plant after the explosions in 2011. Decontamination is performed by removing radioactive particles (mainly cesium) from surfaces of soil, grass and trees, and buildings. Measurement of radiation doses is necessary to reduce exposure, and to determine whether workers can work below dose limits. Protective equipment for decontamination is determined based on the concentration of radiation in contaminated soil and the exposure to dust. Health examinations by physicians are mandated for decontamination workers upon hiring and every 6 months. While there is no possibility of acute radiation injury from decontamination, workers may be anxious about the unclear effects of chronic low level radiation exposure on health. Measures to protect the decontamination workers are the top priority.

ACUTE CHANGES IN PASSIVE GLENOHUMERAL ROTATION FOLLOWING TENNIS PLAY EXPOSURE IN ELITE FEMALE PLAYERS

PubMed Central

Kibler, W. Ben; Myers, Natalie L.; Smith, Belinda J.

2016-01-01

Background Alterations in glenohumeral (GH) rotation especially internal rotation and total range of motion have been associated with altered GH kinematics and susceptibility to injury. Researchers have evaluated long-term change in baseball and tennis players, and short-term changes in baseball players. However, acute (short-term) changes in GH rotation have not been evaluated in tennis players. Hypotheses/Purpose The purpose of this study was to quantify short-term glenohumeral rotational changes within a group of professional women's tennis players following competitive play. It was hypothesized that there would be acute alterations in passive glenohumeral internal rotation and total range of motion following episodes of tennis play. Study Design Cohort Study Methods Passive glenohumeral external rotation (GER), glenohumeral internal rotation (GIR), and total range of motion (TROM) were evaluated in a cohort of 79 professional adult female tennis players. Measurements were taken at three different time points (TP): baseline before match play (TP1), immediately after match play (TP2), and 24-hours after baseline (TP3). Results There was a statistically significant decrease in the mean GIR from TP1 (43 ± 11 °) to TP2 (39 ± 9 °) (p=0.002) and from TP1 to TP3 (38 ± 10 °) (p=0.001). All measures were at the level of minimal detectable change (MDC) (4 °) indicating clinical significance. There was a decrease in mean TROM from TP1 (146 ± 11 °) to TP2 (142 ± 12 °) (p=0.04), which was not above MDC (7 °). Subgroup analysis showed that 47% of the players demonstrated a decrease in GIR beyond MDC, and 37% demonstrated a decrease in TROM beyond MDC. GER remained unchanged across all time points (p>0.05). Conclusion Both GIR and TROM were reduced after acute exposure to tennis play. In a large subgroup of the cohort, the changes were clinically significant and approached values previously demonstrated to be associated with

Safety risks for patients with aspirin-exacerbated respiratory disease after acute exposure to selective nonsteroidal anti-inflammatory drugs and COX-2 inhibitors: Meta-analysis of controlled clinical trials.

PubMed

Morales, Daniel R; Lipworth, Brian J; Guthrie, Bruce; Jackson, Cathy; Donnan, Peter T; Santiago, Virginia H

2014-07-01

Nonsteroidal anti-inflammatory drugs (NSAIDs) cause bronchospasm in susceptible patients with asthma, often termed aspirin-exacerbated respiratory disease (AERD), with the risk being greatest after acute exposure. Selective NSAIDs that preferentially inhibit COX-2 might be safer. We sought to systematically evaluate changes in symptoms and pulmonary function after acute selective NSAID or COX-2 inhibitor exposure in patients with the AERD phenotype. A systematic review of databases was performed to identify all blinded, placebo-controlled clinical trials evaluating acute selective NSAID or COX-2 inhibitor exposure in patients with AERD. Effect estimates for changes in respiratory function and symptoms were pooled by using fixed-effects meta-analysis, with heterogeneity investigated. No significant difference in respiratory symptoms (risk difference, -0.01; 95% CI, -0.03 to 0.01; P = .57), decrease in FEV1 of 20% or greater (RD, 0.00; 95% CI, -0.02 to 0.02; P = .77), or nasal symptoms (RD, -0.01; 95% CI, -0.04 to 0.02; P = .42) occurred with COX-2 inhibitors (eg, celecoxib). Selective NSAID exposure caused respiratory symptoms in approximately 1 in 13 patients with AERD (RD, 0.08; 95% CI, 0.02 to 0.14; P = .01). No significant differences were found according to leukotriene antagonist exposure or whether NSAIDs were randomly allocated. According to clinical trial evidence in patients with stable mild-to-moderate asthma with AERD, acute exposure to COX-2 inhibitors is safe, and selective NSAIDs exhibit a small risk. Thus COX-2 inhibitors could be used in patients with AERD or in patients with general asthma unwilling to risk nonselective NSAID exposure when oral challenge tests are unavailable. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats.

PubMed

Masini, Cher V; Nyhuis, Tara J; Sasse, Sarah K; Day, Heidi E W; Campeau, Serge

2011-05-01

Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress.

Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats

PubMed Central

MASINI, CHER V.; NYHUIS, TARA J.; SASSE, SARAH K.; DAY, HEIDI E. W.; CAMPEAU, SERGE

2015-01-01

Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress. PMID:21438772

Long-term exposure to air pollution is associated with survival following acute coronary syndrome

PubMed Central

Tonne, Cathryn; Wilkinson, Paul

2013-01-01

Aims The aim of this study was to determine (i) whether long-term exposure to air pollution was associated with all-cause mortality using the Myocardial Ischaemia National Audit Project (MINAP) data for England and Wales, and (ii) the extent to which exposure to air pollution contributed to socioeconomic inequalities in prognosis. Methods and results Records of patients admitted to hospital with acute coronary syndrome (ACS) in MINAP collected under the National Institute for Cardiovascular Outcomes Research were linked to modelled annual average air pollution concentrations for 2004–10. Hazard ratios for mortality starting 28 days after admission were estimated using Cox proportional hazards models. Among the 154 204 patients included in the cohort, the average follow-up was 3.7 years and there were 39 863 deaths. Mortality rates were higher for individuals exposed to higher levels of particles with a diameter of ≤2.5 µm (PM2.5; PM, particulate matter): the fully adjusted hazard ratio for a 10 µg/m3 increase in PM2.5 was 1.20 (95% CI 1.04–1.38). No associations were observed for larger particles or oxides of nitrogen. Air pollution explained socioeconomic inequalities in survival to only a small extent. Conclusion Mortality from all causes was higher among individuals with greater exposure to PM2.5 in survivors of hospital admission for ACS in England and Wales. Despite higher exposure to PM2.5 among those from more deprived areas, such exposure was a minor contribution to the socioeconomic inequalities in prognosis following ACS. Our findings add to the evidence of mortality associated with long-term exposure to fine particles. PMID:23423735

Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident

PubMed Central

Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

2015-01-01

Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters. PMID:25862700

Acute and chronic toxicity of aluminum to a unionid mussel (Lampsilis siliquoidea) and an amphipod (Hyalella azteca) in water‐only exposures

USGS Publications Warehouse

Wang, Ning; Ivey, Chris D.; Brunson, Eric L.; Cleveland, Danielle; Ingersoll, Christopher G.; Stubblefield, William A.; Cardwell, Allison S.

2018-01-01

The US Environmental Protection Agency (USEPA) is reviewing the protectiveness of the national ambient water quality criteria (WQC) for aluminum (Al) and compiling a toxicity data set to update the WQC. Freshwater mussels are one of the most imperiled groups of animals in the world, but little is known about their sensitivity to Al. The objective of the present study was to evaluate acute 96‐h and chronic 28‐d toxicity of Al to a unionid mussel (Lampsilis siliquoidea) and a commonly tested amphipod (Hyalella azteca) at a pH of 6 and water hardness of 100 mg/L as CaCO3. The acute 50% effect concentration (EC50) for survival of both species was >6200 μg total Al/L. The EC50 was greater than all acute values in the USEPA acute Al data set for freshwater species at a pH range of 5.0 to <6.5 and hardness normalized to 100 mg/L, indicating that the mussel and amphipod were insensitive to Al in acute exposures. The chronic 20% effect concentration (EC20) based on dry weight was 163 μg total Al/L for the mussel and 409 μg total Al/L for the amphipod. Addition of the EC20s to the USEPA chronic Al data set for pH 5.0 to <6.5 would rank the mussel (L. siliquoidea) as the fourth most sensitive species and the amphipod (H. azteca) as the fifth most sensitive species, indicating the 2 species were sensitive to Al in chronic exposures. The USEPA‐proposed acute and chronic WQC for Al would adequately protect the mussel and amphipod tested; however, inclusion of the chronic data from the present study and recalculation of the chronic criterion would likely lower the proposed chronic criterion. 

Nuclear and radiological terrorism: continuing education article.

PubMed

Anderson, Peter D; Bokor, Gyula

2013-06-01

Terrorism involving radioactive materials includes improvised nuclear devices, radiation exposure devices, contamination of food sources, radiation dispersal devices, or an attack on a nuclear power plant or a facility/vehicle that houses radioactive materials. Ionizing radiation removes electrons from atoms and changes the valence of the electrons enabling chemical reactions with elements that normally do not occur. Ionizing radiation includes alpha rays, beta rays, gamma rays, and neutron radiation. The effects of radiation consist of stochastic and deterministic effects. Cancer is the typical example of a stochastic effect of radiation. Deterministic effects include acute radiation syndrome (ARS). The hallmarks of ARS are damage to the skin, gastrointestinal tract, hematopoietic tissue, and in severe cases the neurovascular structures. Radiation produces psychological effects in addition to physiological effects. Radioisotopes relevant to terrorism include titrium, americium 241, cesium 137, cobalt 60, iodine 131, plutonium 238, califormium 252, iridium 192, uranium 235, and strontium 90. Medications used for treating a radiation exposure include antiemetics, colony-stimulating factors, antibiotics, electrolytes, potassium iodine, and chelating agents.

Application of physiologically based pharmacokinetic modeling in setting acute exposure guideline levels for methylene chloride.

PubMed

Bos, Peter Martinus Jozef; Zeilmaker, Marco Jacob; van Eijkeren, Jan Cornelis Henri

2006-06-01

Acute exposure guideline levels (AEGLs) are derived to protect the human population from adverse health effects in case of single exposure due to an accidental release of chemicals into the atmosphere. AEGLs are set at three different levels of increasing toxicity for exposure durations ranging from 10 min to 8 h. In the AEGL setting for methylene chloride, specific additional topics had to be addressed. This included a change of relevant toxicity endpoint within the 10-min to 8-h exposure time range from central nervous system depression caused by the parent compound to formation of carboxyhemoglobin (COHb) via biotransformation to carbon monoxide. Additionally, the biotransformation of methylene chloride includes both a saturable step as well as genetic polymorphism of the glutathione transferase involved. Physiologically based pharmacokinetic modeling was considered to be the appropriate tool to address all these topics in an adequate way. Two available PBPK models were combined and extended with additional algorithms for the estimation of the maximum COHb levels. The model was validated and verified with data obtained from volunteer studies. It was concluded that all the mentioned topics could be adequately accounted for by the PBPK model. The AEGL values as calculated with the model were substantiated by experimental data with volunteers and are concluded to be practically applicable.

Time course of systemic oxidative stress and inflammatory response induced by an acute exposure to Residual Oil Fly Ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchini, T.; Magnani, N.D.; Paz, M.L.

2014-01-15

It is suggested that systemic oxidative stress and inflammation play a central role in the onset and progression of cardiovascular diseases associated with the exposure to particulate matter (PM). The aim of this work was to evaluate the time changes of systemic markers of oxidative stress and inflammation, after an acute exposure to Residual Oil Fly Ash (ROFA). Female Swiss mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight) or saline solution, and plasma levels of oxidative damage markers [thiobarbituric acid reactive substances (TBARSs) and protein carbonyls], antioxidant status [reduced (GSH) and oxidized (GSSG) glutathione, ascorbic acidmore » levels, and superoxide dismutase (SOD) activity], cytokines levels, and intravascular leukocyte activation were evaluated after 1, 3 or 5 h of exposure. Oxidative damage to lipids and decreased GSH/GSSG ratio were observed in ROFA-exposed mice as early as 1 h. Afterwards, increased protein oxidation, decreased ascorbic acid content and SOD activity were found in this group at 3 h. The onset of an adaptive response was observed at 5 h after the ROFA exposure, as indicated by decreased TBARS plasma content and increased SOD activity. The observed increase in oxidative damage to plasma macromolecules, together with systemic antioxidants depletion, may be a consequence of a systemic inflammatory response triggered by the ROFA exposure, since increased TNF-α and IL-6 plasma levels and polymorphonuclear leukocytes activation was found at every evaluated time point. These findings contribute to the understanding of the increase in cardiovascular morbidity and mortality, in association with environmental PM inhalation. - Highlights: • An acute exposure to ROFA triggers the occurrence of systemic oxidative stress. • Changes in plasmatic oxidative stress markers appear as early as 1 h after exposure. • ROFA induces proinflammatory cytokines release and intravascular leukocyte activation. �

Internal radiation exposure of Ground Self-Defense Force members involved in the management of the Fukushima Nuclear Power Plant disaster.

PubMed

Naoi, Yutaka; Fujikawa, Akira; Kyoto, Yukishige; Kunishima, Naoaki; Ono, Masahiro; Watanabe, Yukie

2013-01-01

When the Great East Japan Earthquake occurred on March 11, 2011, the Ground Self-Defense Force (GSDF) was dispatched nationally to Northeast area in Japan. The highly trained GSDF members were simultaneously assigned to various missions for the Fukushima Nuclear Power Plants disaster. The missions of GSDF terminated on August 31, 2011. Special medical examinations were conducted for the members as they returned to each military unit. GSDF members who were assigned to the nuclear power plant were at risk of radiation exposure; therefore, pocket dosimeters were used to assess external radiation exposure. A few months after the mission was terminated, measurements of internal radiation exposure were performed. This is the first report of the internal exposure of GSDF members who worked in the restricted radiation contamination area. Here, we report the amounts of internal and external exposure of and the equipment used by the GSDF members.

Acute and chronic in vivo effects of exposure to nicotine and propylene glycol from an E-cigarette on mucociliary clearance in a murine model

PubMed Central

Laube, Beth L.; Afshar-Mohajer, Nima; Koehler, Kirsten; Chen, Gang; Lazarus, Philip; Collaco, Joseph M.; McGrath-Morrow, Sharon A.

2017-01-01

Objective To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. Methods C57BL/6 male mice (age 10.5 ±2.4 weeks) were exposed for 20min/day to E-cigarette aerosol generated by a Joyetech 510-T® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99mtechnetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. Results MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6±5.2%, 7.5±2.8% and 11.2±5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ±8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ±4.6)% (p < .05). Serum cotinine levels were <0.5ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. Conclusions In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine. PMID:28651446

No detectable bioeffects following acute exposure to high peak power ultra-wide band electromagnetic radiation in rats.

PubMed

Walters, T J; Mason, P A; Sherry, C J; Steffen, C; Merritt, J H

1995-06-01

A wide range assessment of the possible bioeffects of an acute exposure to high peak power ultra-wide band (UWB) electromagnetic radiation was performed in rats. The UWB-exposure consisted of 2 min of pulsed (frequency: 60 Hz, pulse width: 5-10 ns) UWB (bandwidth: 0.25-2.50 GHz) electromagnetic radiation. Rats were examined using one of the following: 1) a functional observational battery (FOB); 2) a swimming performance test; 3) a complete panel of blood chemistries; or 4) determination of the expression of the c-fos protein in immunohistologically-stained sections of the brain. No significant differences were found between UWB- or sham-exposed rats on any of the measured parameters.

Effects of acute and chronic exposures of fluoxetine on the Chinese fish, topmouth gudgeon Pseudorasbora parva.

PubMed

Chen, Hongxing; Zeng, Xiangfeng; Mu, Lei; Hou, Liping; Yang, Bin; Zhao, Jianliang; Schlenk, Daniel; Dong, Wu; Xie, Lingtian; Zhang, Qianru

2018-09-30

Fluoxetine is a selective serotonin reuptake inhibitor used as an antidepressant and has been frequently detected in aquatic environments. However, its effects in fish from Asia remain relatively less studied. In this study, the topmouth gudgeon Pseudorasbora parva was exposed to 0, 50, and 200 µg/L of fluoxetine for 4 h and 42 d. The effects of fluoxetine on biometrics were compared to biochemical endpoints indicative of stress in different fish tissues (brain, liver, gills and intestine) following exposures. In fish exposed for 42 d, lipid peroxidation endpoints were enhanced 80% in the liver and gills. Acetylcholinesterase (AChE) activity was increased 40% after exposure to 50 µg/L and 55% at 200 µg/L following 4 h exposure. In contrast AChE was increased 26% (at 50 µg/L) after 42 d of exposures. Enhanced ethoxyresorufin-O-deethylase activity (EROD) was detected only in fish exposed to 50 µg/L of fluoxetine for 4 h. The activity of α-glucosidase (α-Glu) was also induced (at 200 µg/L) after 4 h of exposure. After 4 h of exposure, the activities of proteases in the intestine were generally inhibited at 200 µg/L. Both 4 h and 42 d exposures resulted in an increased hepatosomatic index (HSI) but did not affect the condition factor (CF). Our results demonstrate that fluoxetine significantly altered biochemical endpoints in P. parva after acute exposure and the morphological changes in liver size were not observed until 42 d of exposure. Copyright © 2018. Published by Elsevier Inc.

Circadian and Sex Differences After Acute High-Altitude Exposure: Are Early Acclimation Responses Improved by Blue Light?

PubMed

Silva-Urra, Juan A; Núñez-Espinosa, Cristian A; Niño-Mendez, Oscar A; Gaitán-Peñas, Héctor; Altavilla, Cesare; Toro-Salinas, Andrés; Torrella, Joan R; Pagès, Teresa; Javierre, Casimiro F; Behn, Claus; Viscor, Ginés

2015-12-01

The possible effects of blue light during acute hypoxia and the circadian rhythm on several physiological and cognitive parameters were studied. Fifty-seven volunteers were randomly assigned to 2 groups: nocturnal (2200-0230 hours) or diurnal (0900-1330 hours) and exposed to acute hypoxia (4000 m simulated altitude) in a hypobaric chamber. The participants were illuminated by blue LEDs or common artificial light on 2 different days. During each session, arterial oxygen saturation (Spo2), blood pressure, heart rate variability, and cognitive parameters were measured at sea level, after reaching the simulated altitude of 4000 m, and after 3 hours at this altitude. The circadian rhythm caused significant differences in blood pressure and heart rate variability. A 4% to 9% decrease in waking nocturnal Spo2 under acute hypoxia was observed. Acute hypoxia also induced a significant reduction (4%-8%) in systolic pressure, slightly more marked (up to 13%) under blue lighting. Women had significantly increased systolic (4%) and diastolic (12%) pressures under acute hypoxia at night compared with daytime pressure; this was not observed in men. Some tendencies toward better cognitive performance (d2 attention test) were seen under blue illumination, although when considered together with physiological parameters and reaction time, there was no conclusive favorable effect of blue light on cognitive fatigue suppression after 3 hours of acute hypobaric hypoxia. It remains to be seen whether longer exposure to blue light under hypobaric hypoxic conditions would induce favorable effects against fatigue. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Cognitive functions and cerebral oxygenation changes during acute and prolonged hypoxic exposure.

PubMed

Davranche, Karen; Casini, Laurence; Arnal, Pierrick J; Rupp, Thomas; Perrey, Stéphane; Verges, Samuel

2016-10-01

The present study aimed to assess specific cognitive processes (cognitive control and time perception) and hemodynamic correlates using functional near-infrared spectroscopy (fNIRS) during acute and prolonged high-altitude exposure. Eleven male subjects were transported via helicopter and dropped at 14 272 ft (4 350 meters) of altitude where they stayed for 4 days. Cognitive tasks, involving a conflict task and temporal bisection task, were performed at sea level the week before ascending to high altitude, the day of arrival (D0), the second (D2) and fourth (D4) day at high altitude. Cortical hemodynamic changes in the prefrontal cortex (PFC) area were monitored with fNIRS at rest and during the conflict task. Results showed that high altitude impacts information processing in terms of speed and accuracy. In the early hours of exposure (D0), participants displayed slower reaction times (RT) and decision errors were twice as high. While error rate for simple spontaneous responses remained twice that at sea level, the slow-down of RT was not detectable after 2 days at high-altitude. The larger fNIRS responses from D0 to D2 suggest that higher prefrontal activity partially counteracted cognitive performance decrements. Cognitive control, assessed through the build-up of a top-down response suppression mechanism, the early automatic response activation and the post-error adjustment were not impacted by hypoxia. However, during prolonged hypoxic exposure the temporal judgments were underestimated suggesting a slowdown of the internal clock. A decrease in cortical arousal level induced by hypoxia could consistently explain both the slowdown of the internal clock and the persistence of a higher number of errors after several days of exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Acute Air Pollution Exposure and Blood Pressure at Delivery Among Women With and Without Hypertension

PubMed Central

Männistö, Tuija; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S. Katherine

2015-01-01

BACKGROUND Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known. METHODS We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002–2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect. RESULTS Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%–4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units. CONCLUSIONS Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission. PMID:24795401

Solid cancer mortality associated with chronic external radiation exposure at the French atomic energy commission and nuclear fuel company.

PubMed

Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

2011-07-01

Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar period, company and socioeconomic status (SES)]. During the period 1968-2004, there were 2,035 solid cancers among the 36,769 CEA-AREVA NC workers. Cumulative external radiation exposure was assessed for the period 1950-2004, and the mean cumulative dose was 12.1 mSv. Mortality rates for all causes and all solid cancers were both significantly lower in this cohort than in the general population. A significant excess of deaths from pleural cancer, not associated with cumulative external dose, was observed, probably due to past asbestos exposure. We observed a significant excess of melanoma, also unassociated with dose. Although cumulative external dose was not associated with mortality from all solid cancers, the central estimated excess relative risk (ERR) per Sv of 0.46 for solid cancer mortality was higher than the 0.26 calculated for male Hiroshima and Nagasaki A-bomb survivors 50 years or older and exposed at the age of 30 years or older. The modification of our results after stratification for SES demonstrates the importance of this characteristic in occupational studies, because it makes it possible to take class-based lifestyle differences into account, at least partly. These results show the great potential of a further joint international study of

Characterising multi-level effects of acute pressure exposure on a shallow-water invertebrate: insights into the kinetics and hierarchy of the stress response.

PubMed

Morris, James P; Thatje, Sven; Ravaux, Juliette; Shillito, Bruce; Hauton, Chris

2015-08-01

Hydrostatic pressure is an important, ubiquitous, environmental variable of particular relevance in the marine environment. However, it is widely overlooked despite recent evidence that some marine ectotherms may be demonstrating climate-driven bathymetric range shifts. Wide-ranging effects of increased hydrostatic pressure have been observed from the molecular through to the behavioural level. Still, no study has simultaneously examined these multiple levels of organisation in a single experiment in order to understand the kinetics, hierarchy and interconnected nature of such responses during an acute exposure, and over a subsequent recovery period. Here, we quantify the transcription of a set of previously characterised genes during and after acute pressure exposure in adults of the shrimp Palaemonetes varians. Further, we perform respiratory rate and behavioural analysis over the same period. Increases in expression of genes associated with stress and metabolism were observed during and after high-pressure exposure. Respiratory rate increased during exposure and into the recovery period. Finally, differential behaviour was observed under elevated hydrostatic pressure in comparison to ambient pressure. Characterising generalised responses to acute elevated pressure is a vital precursor to longer-term, acclimation-based pressure studies. Results provide a novel insight into what we term the overall stress response (OSR) to elevated pressure; a concept that we suggest to be applicable to other environmental stressors. We highlight the importance of considering more than a single component of the stress response in physiological studies, particularly in an era where environmental multi-stressor studies are proliferating. © 2015. Published by The Company of Biologists Ltd.

EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS HEALTHY AND MONOCROTALINE-TREATED SPRAGUE-DAWLEY RATS

EPA Science Inventory

EFFECTS OF ACUTE EXPOSURE TO CONCENTRATED AMBIENT PARTICULATES ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN HEALTHY AND MONOCROTALINE-TREATED SPRAGUE-DAWLEY RATS. LB Wichers1, JP Nolan2, DW Winsett2, UP Kodavanti2, MCJ Schladweiler2, DL Costa2, and WP ...

Trends in radiation exposure from clinical nuclear medicine procedures in Shanghai, China.

PubMed

Yi, Yanling; Zheng, Junzheng; Zhuo, Weihai; Gao, Linfeng

2012-03-01

This study was designed to assess the trends in the frequencies of nuclear medicine procedures in Shanghai, China, and to determine their contributions to the per capita effective dose to the Shanghai population. The mean activities of radionuclides administered by nuclear medicine departments were compared with the Chinese national guidelines on diagnostic reference levels. On the basis of the three surveys carried out by Shanghai Municipal Center for Disease Control and Prevention in 1996, 1998, and 2008, the typically administered radiopharmaceuticals, levels of activity, the number of procedures, and population were systematically analyzed to assess the frequencies of nuclear medicine procedures and the per capita effective dose. The frequencies were approximately 2.77, 3.46, and 6.63 per 1000 people in 1996, 1998, and 2008, respectively. The annual per capita doses from diagnostic nuclear medicine were estimated to be 0.016, 0.022, and 0.032 mSv in 1996, 1998, and 2008, respectively. The annual frequency of therapeutic nuclear medicine procedures increased from 0.131 to 0.430 per 1000 people in the intervening 12 years. In the 12 years before 2008, diagnostic and therapeutic procedures in nuclear medicine in Shanghai increased continuously, and the annual per capita dose doubled. Increases in PET imaging and bone scans were the major contributors to the increasing frequency and magnitude of radiation exposure to the population. The activities administered for most diagnostic procedures were generally consistent with the designated reference levels.

Sulfur mustard induced nuclear translocation of glyceraldehyde-3-phosphate-dehydrogenase (GAPDH).

PubMed

Steinritz, Dirk; Weber, Jana; Balszuweit, Frank; Thiermann, Horst; Schmidt, Annette

2013-12-05

Sulfur Mustard (SM) is a vesicant chemical warfare agent, which is acutely toxic to a variety of organ systems including skin, eyes, respiratory system and bone marrow. The underlying molecular pathomechanism was mainly attributed to the alkylating properties of SM. However, recent studies have revealed that cellular responses to SM exposure are of more complex nature and include increased protein expression and protein modifications that can be used as biomarkers. In order to confirm already known biomarkers, to detect potential new ones and to further elucidate the pathomechanism of SM, we conducted large-scale proteomic experiments based on a human keratinocyte cell line (HaCaT) exposed to SM. Surprisingly, our analysis identified glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) as one of the up-regulated proteins after exposure of HaCaT cells to SM. In this paper we demonstrate the sulfur mustard induced nuclear translocation of GAPDH in HaCaT cells by 2D gel-electrophoresis (2D GE), immunocytochemistry (ICC), Western Blot (WB) and a combination thereof. 2D GE in combination with MALDI-TOF MS/MS analysis identified GAPDH as an up-regulated protein after SM exposure. Immunocytochemistry revealed a distinct nuclear translocation of GAPDH after exposure to 300μM SM. This finding was confirmed by fractionated WB analysis. 2D GE and subsequent immunoblot staining of GAPDH demonstrated two different spot locations of GAPH (pI 7.0 and pI 8.5) that are related to cytosolic or nuclear GAPDH respectively. After exposure to 300μM SM a significant increase of nuclear GAPDH at pI 8.5 occurred. Nuclear GAPDH has been associated with apoptosis, detection of structural DNA alterations, DNA repair and regulation of genomic integrity and telomere structure. The results of our study add new aspects to the pathophysiology of sulfur mustard toxicity, yet further studies will be necessary to reveal the specific function of nuclear GAPDH in the pathomechanism of sulfur mustard

A cohort study of the acute and chronic respiratory effects of toner exposure among handlers: a longitudinal analyses from 2004 to 2013.

PubMed

Ikegami, Kazunori; Hasegawa, Masayuki; Ando, Hajime; Hata, Koichi; Kitamura, Hiroko; Ogami, Akira; Higashi, Toshiaki

2016-10-08

This study examines the acute and chronic respiratory effects of toner exposure based on markers for interstitial pneumonia, oxidative stress and pulmonary function tests. A total of 112 subjects working in a Japanese toner and photocopier manufacturing company participated in this study in 2004. We annually conducted personal exposure measurements, pulmonary function tests, chest X-ray examinations, biomarkers, and questionnaires on respiratory symptoms to the subjects. We report in this paper the results of the analysis of combined annual survey point data from 2004 to 2008 and data from three annual survey points, 2004, 2008, and 2013. During these survey periods, we observed that none of subjects had a new onset of respiratory disease or died of such a disease. In both the analyses, there were no significant differences in each biomarker and pulmonary function tests within the subjects, nor between a toner-handling group and a non-toner-handling group, except for a few results on pulmonary function tests. The findings of this study suggest that there were no acute and chronic respiratory effects of toner exposure in this cohort group, although the number of subjects was small and the level of toner exposure in this worksite was low.

A cohort study of the acute and chronic respiratory effects of toner exposure among handlers: a longitudinal analyses from 2004 to 2013

PubMed Central

IKEGAMI, Kazunori; HASEGAWA, Masayuki; ANDO, Hajime; HATA, Koichi; KITAMURA, Hiroko; OGAMI, Akira; HIGASHI, Toshiaki

2016-01-01

This study examines the acute and chronic respiratory effects of toner exposure based on markers for interstitial pneumonia, oxidative stress and pulmonary function tests. A total of 112 subjects working in a Japanese toner and photocopier manufacturing company participated in this study in 2004. We annually conducted personal exposure measurements, pulmonary function tests, chest X–ray examinations, biomarkers, and questionnaires on respiratory symptoms to the subjects. We report in this paper the results of the analysis of combined annual survey point data from 2004 to 2008 and data from three annual survey points, 2004, 2008, and 2013. During these survey periods, we observed that none of subjects had a new onset of respiratory disease or died of such a disease. In both the analyses, there were no significant differences in each biomarker and pulmonary function tests within the subjects, nor between a toner–handling group and a non–toner–handling group, except for a few results on pulmonary function tests. The findings of this study suggest that there were no acute and chronic respiratory effects of toner exposure in this cohort group, although the number of subjects was small and the level of toner exposure in this worksite was low. PMID:27021062

Acute exposure to gas-supersaturated water does not affect reproductive success of female adult chinook salmon late in maturation

USGS Publications Warehouse

Gale, William L.; Maule, A.G.; Postera, A.; Peters, M.H.

2004-01-01

At times, total dissolved gas concentrations in the Columbia and Snake rivers have been elevated due to involuntary spill from high spring runoff and voluntary spill used as a method to pass juvenile salmonids over dams. The goal of this project was to determine if acute exposure to total dissolved gas supersaturation (TDGS) affects the reproductive performance of female chinook salmon late in their maturation. During this study, adult female spring chinook salmon were exposed to mean TDGS levels of 114.1 % to 125.5%. We ended exposures at first mortality, or at the appearance of impending death. Based on this criterion, exposures lasted from 10 to 68 h and were inversely related to TDGS. There was no effect of TDGS on pre-spawning mortality or fecundity when comparing treatment fish to experimental controls or the general hatchery population four to six weeks after exposures. Egg quality, based on egg weight and egg diameter, did not differ between treatment and control fish. Fertilization rate and survival to eyed-stage was high (>94%) for all groups. With the exception of Renibacterium salmoninarum (the causative agent of bacterial kidney disease; BKD), no viral or bacterial fish pathogens were isolated from experimental fish. The prevalence (about 45%) and severity of R. salmoninarum did not differ among the groups or the general hatchery population. We conclude that these acute exposures to moderate levels of gas-supersaturated water-perhaps similar to that experienced by immigrating adult salmon as they approach and pass a hydropower dam on the Columbia River-did not affect reproductive success of female chinook salmon late in their maturation. These results are most applicable to summer and fall chinook salmon, which migrate in the summer/fall and spawn shortly after reaching their natal streams. Published in 2004 by John Wiley and Sons, Ltd.

Molecular epidemiology of acute leukemia in children: causal model, interaction of three factors-susceptibility, environmental exposure and vulnerability period.

PubMed

Mejía-Aranguré, Juan Manuel

Acute leukemias have a huge morphological, cytogenetic and molecular heterogeneity and genetic polymorphisms associated with susceptibility. Every leukemia presents causal factors associated with the development of the disease. Particularly, when three factors are present, they result in the development of acute leukemia. These phenomena are susceptibility, environmental exposure and a period that, for this model, has been called the period of vulnerability. This framework shows how the concepts of molecular epidemiology have established a reference from which it is more feasible to identify the environmental factors associated with the development of leukemia in children. Subsequently, the arguments show that only susceptible children are likely to develop leukemia once exposed to an environmental factor. For additional exposure, if the child is not susceptible to leukemia, the disease does not develop. In addition, this exposure should occur during a time window when hematopoietic cells and their environment are more vulnerable to such interaction, causing the development of leukemia. This model seeks to predict the time when the leukemia develops and attempts to give a context in which the causality of childhood leukemia should be studied. This information can influence and reduce the risk of a child developing leukemia. Copyright © 2016 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Risk assessment of the cumulative acute exposure of Hungarian population to organophosphorus pesticide residues with regard to consumers of plant based foods.

PubMed

Zentai, Andrea; Szabó, István J; Kerekes, Kata; Ambrus, Árpád

2016-03-01

Based on the Hungarian pesticide residues monitoring data of the last five years and the consumption data collected within a 3-day dietary record survey in 2009 (more than 2 million pesticide residue results and almost 5000, 0-101-year-old consumers 3 non-consecutive-day personal fruit and vegetable consumption data), the cumulative acute exposure of organophosphorus pesticide residues was evaluated. The relative potency factor approach was applied, with acephate chosen as index compound. According to our conservative calculation method, applying the measured residues only, the 99.95% of the 99th percentiles of calculated daily intakes was at or below 87 μg/kgbwday, indicating that the cumulative acute exposure of the whole Hungarian population (including all age classes) to organophosphorus compounds was not a health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acute toxic nephropathies: clinical pathologic correlations.

PubMed

Muehrcke, R C; Volini, F I; Morris, A M; Moles, J B; Lawrence, A G

1976-01-01

Man's ever increasing exposure to numerous drugs and chemicals, which are the results of medical and industrial progress, produces a by-product of acute toxic nephropathies. These include acute toxic renal failure, drug-induced acute oliguric renal failure, acute hemorrhagic glomerulonephritis, nephrotic syndrome, tubular disturbances and potassium deficiency. In depth information is provided for the previously mentioned disorders.

Pyrethroid pesticide exposure and risk of childhood acute lymphocytic leukemia in Shanghai.

PubMed

Ding, Guodong; Shi, Rong; Gao, Yu; Zhang, Yan; Kamijima, Michihiro; Sakai, Kiyoshi; Wang, Guoquan; Feng, Chao; Tian, Ying

2012-12-18

Significant amounts of pyrethroid pesticides are used throughout China. Previous studies have suggested that exposure to pesticides may increase the risk of childhood cancer; however, few studies have focused on pyrethroid metabolites. We investigated five nonspecific metabolites of pyrethroid pesticides found in children's urine and examined the correlation with childhood leukemia. We conducted a hospital-based case-control study of childhood acute lymphocytic leukemia (ALL) in Shanghai between 2010 and 2011. The study included 176 children aged 0-14 years and 180 controls matched for age and sex. Compared with those in the lowest quartiles of total and individual metabolites, the highest quartiles were associated with an approximate 2-fold increased risk of ALL [total metabolites: odds ratio (OR) = 2.75, 95% confidence interval (CI), 1.43-5.29; cis-DCCA: OR = 2.21, 95% CI, 1.16-4.19; trans-DCCA: OR = 2.33, 95% CI, 1.23-4.41; and 3-PBA: OR = 1.84, 95% CI, 1.00-3.38], and most of the positive trends were significant (p < 0.05). Our findings suggest that urinary levels of pyrethroid metabolites may be associated with an elevated risk of childhood ALL and represent a previously unreported quantitative exposure assessment for childhood leukemia.

Effect of acute exposure to a complex fragrance on lexical decision performance.

PubMed

Gaygen, Daniel E; Hedge, Alan

2009-01-01

This study tested the effect of acute exposure to a commercial air freshener, derived from fragrant botanical extracts, at an average concentration of 3.16 mg/m(3) total volatile organic compounds on the lexical decision performance of 28 naive participants. Participants attended two 18-min sessions on separate days and were continuously exposed to the fragrance in either the first (F/NF) or second (NF/F) session. Participants were not instructed about the fragrance. Exposure to the fragrance did not affect high-frequency word recognition. However, there was an order of administration effect for low-frequency word recognition accuracy. When the fragrance was administered first before the no-odor control condition, it did not affect accuracy, but when it was administered second after the control condition, it significantly decreased low-frequency word recognition accuracy. Reaction times to low-frequency words were significantly slower than those for high-frequency words, but no effect of either fragrance or order of administration on reaction times was found. The presence of fragrance in the second session apparently served as a distraction that impaired lexical task performance accuracy. The introduction of fragrances into buildings may not necessarily facilitate all aspects of work performance as anticipated.

Acute exposure to 2G phase shifts the rat circadian timing system

NASA Technical Reports Server (NTRS)

Hoban-Higgins, T. M.; Murakami, D. M.; Tandon, T.; Fuller, C. A.

1995-01-01

The circadian timing system (CTS) provides internal and external temporal coordination of an animal's physiology and behavior. In mammals, the generation and coordination of these circadian rhythms is controlled by a neural pacemaker, the suprachiasmatic nucleus (SCN), located within the hypothalamus. The pacemaker is synchronized to the 24 hour day by time cures (zeitgebers) such as the light/dark cycle. When an animal is exposed to an environment without time cues, the circadian rhythms maintain internal temporal coordination, but exhibit a 'free-running' condition in which the period length is determined by the internal pacemaker. Maintenance of internal and external temporal coordination are critical for normal physiological and psychological function in human and non-human primates. Exposure to altered gravitational environments has been shown to affect the amplitude, mean, and timing of circadian rhythms in species ranging from unicellular organisms to man. However, it has not been determined whether altered gravitational fields have a direct effect on the neural pacemaker, or affect peripheral parameters. In previous studies, the ability of a stimulus to phase shift circadian rhythms was used to determine whether a stimulus has a direct effect on the neural pacemaker. The present experiment was performed in order to determine whether acute exposure to a hyperdynamic field could phase shift circadian rhythms.

Attempts to counteract phosgene-induced acute lung injury by instant high-dose aerosol exposure to hexamethylenetetramine, cysteine or glutathione.

PubMed

Pauluhn, Jürgen; Hai, Chun Xue

2011-01-01

Phosgene is an important high-production-volume intermediate with widespread industrial use. Consistent with other lung irritants causing ALI (acute lung injury), mode-of-action-based countermeasures remain rudimentary. This study was conducted to analyze whether extremely short high-level exposure to phosgene gas could be mitigated using three different inhaled nucleophiles administered by inhalation instantly after exposure to phosgene. Groups of young adult male Wistar rats were acutely exposed to carbonyl chloride (phosgene) using a directed-flow nose-only mode of exposure of 600 mg/m³ for 1.5 min (225 ppm × min). Immediately after exposure to phosgene gas the rats were similarly exposed to three strong nucleophiles with and without antioxidant properties for 5 or 15 min. The following nucleophiles were used: hexamethylenetetramine (HMT), l-cysteine (Cys), and l-glutathione (GSH). The concentration of the aerosol (mass median aerodynamic diameter 1.7-2 µm) was targeted to be in the range of 1 mg/L. Cys and GSH have antioxidant properties in addition. The calculated alveolar molar dosage of phosgene was 9 µmol/kg. At 15-min exposure duration, the respective inhaled dose of HMT, Csy, and GSH were 111, 103, and 46 µmol/kg, respectively. The alveolar dose of drugs was ~10-times lower. The efficacy of treatment was judged by protein concentrations in bronchoalveolar lavage fluid (BALF) collected 1 day post-exposure. In spite of using optimized aerosolization techniques, none of the nucleophiles chosen had any mitigating effect on BALF-protein extravasation. This finding appear to suggest that inhaled phosgene gas acylates instantly nucleophilic moieties at the site of initial deposition and that the resultant reaction products can not be reactivated even following instant inhalation treatment with competing nucleophilic agents. In spite of using maximal technically attainable concentrations, it appears to be experimentally challenging to deliver

An evaluation of the influence of substrate on the response of juvenile freshwater mussels (fatmucket, Lampsilis siliquoidea) in acute water exposures to ammonia

USGS Publications Warehouse

Miao, J.; Barnhart, M.C.; Brunson, E.L.; Hardesty, D.K.; Ingersoll, C.G.; Wang, N.

2010-01-01

Acute 96-h ammonia toxicity to three-month-old juvenile mussels (Lampsilis siliquoidea) was evaluated in four treatments (water-only, water-only with feeding, water and soil, and water and sand) using an exposure unit designed to maintain consistent pH and ammonia concentrations in overlying water and in pore water surrounding the substrates. Median effect concentrations (EC50s) for total ammonia nitrogen in the four treatments ranged from 5.6 to 7.7mg/L and median lethal concentrations (LC50s) ranged from 7.0 to 11mg/L at a mean pH of 8.4. Similar EC50s or LC50s with overlapping 95% confidence intervals among treatments indicated no influence of substrate on the response of mussels in acute exposures to ammonia. ?? 2010 SETAC.

Acute kidney injury: not just acute renal failure anymore?

PubMed

Dirkes, Susan

2011-02-01

Until recently, no uniform standard existed for diagnosing and classifying acute renal failure. To clarify diagnosis, the Acute Dialysis Quality Initiative group stated its consensus on the need for a clear definition and classification system of renal dysfunction with measurable criteria. Today the term acute kidney injury has replaced the term acute renal failure, with an understanding that such injury is a common clinical problem in critically ill patients and typically is predictive of an increase in morbidity and mortality. A classification system, known as RIFLE (risk of injury, injury, failure, loss of function, and end-stage renal failure), includes specific goals for preventing acute kidney injury: adequate hydration, maintenance of renal perfusion, limiting exposure to nephrotoxins, drug protective strategies, and the use of renal replacement therapies that reduce renal injury.

Acute air pollution exposure and blood pressure at delivery among women with and without hypertension.

PubMed

Männistö, Tuija; Mendola, Pauline; Liu, Danping; Leishear, Kira; Sherman, Seth; Laughon, S Katherine

2015-01-01

Chronic air pollution exposure increases risk for hypertensive disorders of pregnancy, but the effect of acute air pollution exposure on blood pressure during pregnancy is less well known. We studied 151,276 singleton term deliveries from the Consortium on Safe Labor (2002-2008) with clinical blood pressure measured at admission to labor/delivery and diagnoses of hypertensive disorders collected from electronic medical records and hospital discharge summaries. Air pollution exposures were estimated for the admission hour and the 4 hours preceding admission using a modified version of the Community Multiscale Air Quality models and observed air monitoring data. Blood pressure was categorized as normal; high normal; and mild, moderate, or severe hypertension based on pregnancy cut points. Adjusted ordinal logistic regression estimated the odds of women having a higher admission blood pressure category as a function of air pollutant, hypertensive disorders, and their interaction effect. Odds of high blood pressure at admission to labor/delivery were increased in normotensive women after exposure to nitrogen oxides (by 0.2%/5 units), sulfur dioxide (by 0.3%/1 unit), carbon monoxide and several air toxics (by 3%-4%/high exposure). The effects were often similar or stronger among women with gestational hypertension and preeclampsia. Exposure to particulate matter <10 μm increased odds of high blood pressure in women with preeclampsia by 3%/5 units. Air pollution can influence admission blood pressure in term deliveries and may increase likelihood of preeclampsia screening at delivery admission. © Published by Oxford University Press on behalf of American Journal of Hypertension Ltd 2014. This work is written by (a) US Government employees(s) and is in the public domain in the US.

In utero and acute exposure to benzene: investigation of DNA double-strand breaks and DNA recombination in mice.

PubMed

Lau, Annette; Belanger, Christine Lea; Winn, Louise M

2009-05-31

Benzene, a ubiquitous pollutant, has been identified as a human leukemogen and early exposure to environmental carcinogens such as benzene has been linked to childhood leukemia. It is known that genotoxic agents can increase the frequency of DNA double-strand breaks (DSBs), which can initiate DNA recombinational repair mechanisms. In this study we investigated the induction of micronuclei, the formation of gamma-H2A.X as a marker of DNA DSBs, and the induction of somatic DNA recombination events in hematopoietic tissue from pKZ1 transgenic mice exposed acutely or in utero to benzene. Adult male C57Bl/6N mice were treated with a single i.p. injection of benzene, and timed-pregnant females pKZ1 were treated with daily i.p. injections of 200 mg/kg or 400 mg/kg benzene through gestational days 7-15. Acute exposure to 400 mg/kg benzene resulted in a statistically significant increase in the percentage of micronucleated cells in adult male bone marrow cells and in fetal liver and post-natal day 9 bone marrow cells of mice exposed in utero. Immunoblotting techniques did not detect benzene-induced increases in the formation of gamma-H2A.X in bone marrow cells of adult male mice and in maternal bone marrow, fetal liver, and post-natal bone marrow cells after specific time-point exposures. Finally, no recombination events were detected in adult pKZ1 mouse tissue; however, in post-natal day 9 pups in utero exposure to 400 mg/kg of benzene caused a trend towards increasing recombination frequency although this did not reach statistical significance. These results demonstrate that in utero exposure increases the frequency of micronuclei and DNA recombination events in hematopoietic tissue of fetal and post-natal mice and may be an initiating event in the etiology of childhood leukemias. Further investigations into different types of DNA damage and repair pathways are warranted to fully elucidate the role of genotoxic mechanisms in the etiology of benzene-induced childhood

Assessing chronic fish health: An application to a case of an acute exposure to chemically treated crude oil.

PubMed

Mauduit, F; Domenici, P; Farrell, A P; Lacroix, C; Le Floch, S; Lemaire, P; Nicolas-Kopec, A; Whittington, M; Zambonino-Infante, J L; Claireaux, G

2016-09-01

Human alteration of marine ecosystems is substantial and growing. Yet, no adequate methodology exists that provides reliable predictions of how environmental degradation will affect these ecosystems at a relevant level of biological organization. The primary objective of this study was to develop a methodology to evaluate a fish's capacity to face a well-established environmental challenge, an exposure to chemically dispersed oil, and characterize the long-term consequences. Therefore, we applied high-throughput, non-lethal challenge tests to assess hypoxia tolerance, temperature susceptibility and maximal swimming speed as proxies for a fish's functional integrity. These whole animal challenge tests were implemented before (1 month) and after (1 month) juvenile European sea bass (Dicentrarchus labrax) had been acutely exposed (48h) to a mixture containing 0.08gL(-1) of weathered Arabian light crude oil plus 4% dispersant (Corexit© EC9500A), a realistic exposure concentration during an oil spill. In addition, experimental populations were then transferred into semi-natural tidal mesocosm ponds and correlates of Darwinian fitness (growth and survival) were monitored over a period of 4 months. Our results revealed that fish acutely exposed to chemically dispersed oil remained impaired in terms of their hypoxia tolerance and swimming performance, but not in temperature susceptibility for 1 month post-exposure. Nevertheless, these functional impairments had no subsequent ecological consequences under mildly selective environmental conditions since growth and survival were not impacted during the mesocosm pond study. Furthermore, the earlier effects on fish performance were presumably temporary because re-testing the fish 10 months post-exposure revealed no significant residual effects on hypoxia tolerance, temperature susceptibility and maximal swimming speed. We propose that the functional proxies and correlates of Darwinian fitness used here provide a useful

Filgrastim for the treatment of hematopoietic acute radiation syndrome.

PubMed

Farese, A M; MacVittie, T J

2015-09-01

The U.S. Food and Drug Administration (FDA) recently approved Neupogen(®) (filgrastim) for the treatment of patients with radiation-induced myelosuppression following a radiological/nuclear incident. It is the first medical countermeasure currently approved by the FDA for this indication under the criteria of the FDA "animal rule". This article summarizes the consequences of high-dose radiation exposure, a description of the hematopoietic acute radiation syndrome (H-ARS), the use of hematopoietic growth factors in radiation accident victims and current available treatments for H-ARS with an emphasis on the use of Neupogen in this scenario. Copyright 2015 Prous Science, S.A.U. or its licensors. All rights reserved.

OXIDATIVE STRESS PARTICIPATES IN ACUTE LUNG INJURY AND ACTIVATION OF MITOGEN ACTIVATED PROTEIN KINASES (MAPK) FOLLOWING AIR POLLUTION PARTICLE EXPOSURE (PM)

EPA Science Inventory

OXIDATIVE STRESS PARTICIPATES IN ACUTE LUNG INJURY AND ACTIVATION OF MITOGEN ACTIVATED PROTEIN KINASES (MAPK) FOLLOWING AIR POLLUTION PARTICLE EXPOSURE (PM). E S Roberts1, R Jaskot2, J Richards2, and K L Dreher2. 1College of Veterinary Medicine, NC State University, Raleigh, NC a...

Alterations to Juvenile Zebrafish (Danio rerio) Swim Performance after Acute Embryonic Exposure to Sub-lethal Exposures of Hydraulic Fracturing Flowback and Produced Water.

PubMed

Folkerts, Erik J; Blewett, Tamzin A; He, Yuhe; Goss, Greg G

2017-12-01

Hydraulic fracturing flowback and produced water (FPW) is a wastewater produced during fracturing activities in an operating well which is hyper saline and chemically heterogeneous in nature, containing both anthropogenic and petrogenic chemicals. Determination of FPW associated toxicity to embryonic fish is limited, while investigation into how embryonic exposures may affect later life stages is not yet studied. Zebrafish embryos (24hrs post fertilization) were acutely exposed to 2.5% and 5% FPW fractions for either 24 or 48hrs and returned to freshwater. After either 24 or 48h exposures, embryos were examined for expression of 3 hypoxia related genes. Erythropoietin (epoa) but not hypoxia inducible factor (hif1aa) nor hemoglobin -ß chain (hbbe1.1) was up-regulated after either 24 or 48h FPW exposure. Surviving embryos were placed in freshwater and grown to a juvenile stage (60days post fertilization). Previously exposed zebrafish were analyzed for both swim performance (U crit and U max ) and aerobic capacity. Fish exposed to both sediment containing (FPW-S) or sediment free (FPW-SF) FPW displayed significantly reduced aerobic scope and U crit /U max values compared to control conditions. Our results collectively suggest that organics present in our FPW sample may be responsible for sub-lethal fitness and metabolic responses. We provide evidence supporting the theory that the cardio-respiratory system is impacted by FPW exposure. This is the first known research associating embryonic FPW exposures to sub-lethal performance related responses in later life fish stages. Copyright © 2017 Elsevier B.V. All rights reserved.

Brown adipose tissue (BAT) specific vaspin expression is increased after obesogenic diets and cold exposure and linked to acute changes in DNA-methylation.

PubMed

Weiner, Juliane; Rohde, Kerstin; Krause, Kerstin; Zieger, Konstanze; Klöting, Nora; Kralisch, Susan; Kovacs, Peter; Stumvoll, Michael; Blüher, Matthias; Böttcher, Yvonne; Heiker, John T

2017-06-01

Several studies have demonstrated anti-diabetic and anti-obesogenic properties of visceral adipose tissue-derived serine protease inhibitor (vaspin) and so evoked its potential use for treatment of obesity-related diseases. The aim of the study was to unravel physiological regulators of vaspin expression and secretion with a particular focus on its role in brown adipose tissue (BAT) biology. We analyzed the effects of obesogenic diets and cold exposure on vaspin expression in liver and white and brown adipose tissue (AT) and plasma levels. Vaspin expression was analyzed in isolated white and brown adipocytes during adipogenesis and in response to adrenergic stimuli. DNA-methylation within the vaspin promoter was analyzed to investigate acute epigenetic changes after cold-exposure in BAT. Our results demonstrate a strong induction of vaspin mRNA and protein expression specifically in BAT of both cold-exposed and high-fat (HF) or high-sugar (HS) fed mice. While obesogenic diets also upregulated hepatic vaspin mRNA levels, cold exposure tended to increase vaspin gene expression of inguinal white adipose tissue (iWAT) depots. Concomitantly, vaspin plasma levels were decreased upon obesogenic or thermogenic triggers. Vaspin expression was increased during adipogenesis but unaffected by sympathetic activation in brown adipocytes. Analysis of vaspin promoter methylation in AT revealed lowest methylation levels in BAT, which were acutely reduced after cold exposure. Our data demonstrate a novel BAT-specific regulation of vaspin gene expression upon physiological stimuli in vivo with acute epigenetic changes that may contribute to cold-induced expression in BAT. We conclude that these findings indicate functional relevance and potentially beneficial effects of vaspin in BAT function.

Effects of Acutely Intermittent Hypoxic Exposure on Running Economy and Physical Performance in Basketball Players.

PubMed

Kilding, Andrew E; Dobson, Bryan P; Ikeda, Erika

2016-07-01

Kilding, AE, Dobson, BP, and Ikeda, E. Effects of acutely intermittent hypoxic exposure on running economy and physical performance in basketball players. J Strength Cond Res 30(7): 2033-2042, 2016-The aim of this study was to determine the effect of short duration intermittent hypoxic exposure (IHE) on physical performance in basketball players. Using a single-blind placebo-controlled group design, 14 trained basketball players were subjected to 15 days of passive short duration IHE (n = 7), or normoxic control (CON, n = 7), using a biofeedback nitrogen dilution device. A range of physiological, performance, and hematological variables were measured at baseline, and 10 days after IHE. After intervention, the IHE group, relative to the CON group, exhibited improvements in the Yo-Yo intermittent recovery level 1 (+4.8 ± 1.6%; effect size [ES]: 1.0 ± 0.4) and repeated high-intensity exercise test performance (-3.5 ± 1.6%; ES: -0.4 ± 0.2). Changes in hematological parameters were minimal, although soluble transferrin receptor increased after IHE (+9.2 ± 10.1%; ES: 0.3 ± 0.3). Running economy at 11 km·h (-9.0 ± 9.7%; ES: -0.7 ± 0.7) and 13 km·h was improved (-8.2 ± 6.9%; ES: -0.7 ± 0.5), but changes to V[Combining Dot Above]O2peak, HRpeak, and lactate were unclear. In summary, acutely IHE resulted in worthwhile changes in physical performance tests among competitive basketball players. However, physiological measures explaining the performance enhancement were in most part unclear.

Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

NASA Astrophysics Data System (ADS)

Kennedy, Ann; Cengel, Keith

2012-07-01

A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

Changes in Extracellular Striatal Acetylcholine and Brain Seizure Activity Following Acute Exposure to Nerve Against in Freely Moving Guinea Pigs

DTIC Science & Technology

2010-01-01

Literature 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Changes in extracellular striatal acetylcholine and brain seizure activity following...Acetylcholine, acetylcholinesterase, choline, guinea pig, in vivo microdialysis, nerve agents, organophosphorus compounds, sarin, seizure activity ...RESEARCH ARTICLE Changes in extracellular striatal acetylcholine and brain seizure activity following acute exposure to nerve agents in freely

Acute respiratory syndrome after inhalation of waterproofing sprays: a posteriori exposure-response assessment in 102 cases.

PubMed

Vernez, David; Bruzzi, Raffaella; Kupferschmidt, Hugo; De-Batz, Alice; Droz, Pierre; Lazor, Romain

2006-05-01

Waterproofing agents are widely used to protect leather and textiles in both domestic and occupational activities. An outbreak of acute respiratory syndrome following exposure to waterproofing sprays occurred during the winter 2002-2003 in Switzerland. About 180 cases were reported by the Swiss Toxicological Information Centre between October 2002 and March 2003, whereas fewer than 10 cases per year had been recorded previously. The reported cases involved three brands of sprays containing a common waterproofing mixture, that had undergone a formulation change in the months preceding the outbreak. A retrospective analysis was undertaken in collaboration with the Swiss Toxicological Information Centre and the Swiss Registries for Interstitial and Orphan Lung Diseases to clarify the circumstances and possible causes of the observed health effects. Individual exposure data were generated with questionnaires and experimental emission measurements. The collected data was used to conduct numeric simulation for 102 cases of exposure. A classical two-zone model was used to assess the aerosol dispersion in the near- and far-field during spraying. The resulting assessed dose and exposure levels obtained were spread on large scales, of several orders of magnitude. No dose-response relationship was found between exposure indicators and health effects indicators (perceived severity and clinical indicators). Weak relationships were found between unspecific inflammatory response indicators (leukocytes, C-reactive protein) and the maximal exposure concentration. The results obtained disclose a high interindividual response variability and suggest that some indirect mechanism(s) predominates in the respiratory disease occurrence. Furthermore, no threshold could be found to define a safe level of exposure. These findings suggest that the improvement of environmental exposure conditions during spraying alone does not constitute a sufficient measure to prevent future outbreaks of

Dose-related gene expression changes in forebrain following acute, low-level chlorpyrifos exposure in neonatal rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ray, Anamika; Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078; Liu Jing

2010-10-15

Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 h following acute CPF exposure in 7-day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following either one of the four CPF dosages studied (546, 505, 522, and 3,066 genes with 0.1, 0.5, 1.0 and 2.0 mg/kg CPF). Genes were grouped according to dose-related expression patterns using K-means clusteringmore » while gene networks and canonical pathways were evaluated using Ingenuity Pathway Analysis (registered) . Twenty clusters were identified and differential expression of selected genes was verified by RT-PCR. The four largest clusters (each containing from 276 to 905 genes) constituted over 50% of all differentially expressed genes and exhibited up-regulation following exposure to the highest dosage (2 mg/kg CPF). The total number of gene networks affected by CPF also rose sharply with the highest dosage of CPF (18, 16, 18 and 50 with 0.1, 0.5, 1 and 2 mg/kg CPF). Forebrain cholinesterase (ChE) activity was significantly reduced (26%) only in the highest dosage group. Based on magnitude of dose-related changes in differentially expressed genes, relative numbers of gene clusters and signaling networks affected, and forebrain ChE inhibition only at 2 mg/kg CPF, we focused subsequent analyses on this treatment group. Six canonical pathways were identified that were significantly affected by 2 mg/kg CPF (MAPK, oxidative stress, NF{Kappa}B, mitochondrial dysfunction, arylhydrocarbon receptor and adrenergic receptor signaling). Evaluation of different cellular functions of the differentially expressed genes suggested changes related to olfactory receptors, cell adhesion

Acute exposure to ethanol on gestational day 15 affects social motivation of female offspring.

PubMed

Varlinskaya, Elena I; Mooney, Sandra M

2014-03-15

Alterations in social behavior are a hallmark of many neurodevelopmental disorders in humans. In rodents, social behavior is affected by prenatal insults. The outcomes are dependent on the timing of the insult as well as the sex and age of the animal tested. The limbic system is particularly important for social behavior, and a peak of neurogenesis within this system occurs on gestational day (G)15. Neurons appear particularly vulnerable to ethanol insult around the time they become post-mitotic. We tested the hypothesis that acute exposure to ethanol on G15 would result in significant social behavior deficits. Accordingly, Long Evans pregnant females were injected with ethanol (2.9 g/kg) or an equivalent volume of saline on G15. Offspring were assessed in a modified social interaction test on postnatal day (P) 28, P42, or P75, i.e., during early adolescence, late adolescence, or young adulthood. Prenatal ethanol exposure decreased social investigation in P28 females and transformed social preference into social avoidance in 75-day-old females. Contact behavior, play fighting, and locomotor activity differed as a function of age, but were not significantly affected by ethanol exposure. Males demonstrated significantly more contact behavior and play fighting at P42 than at P28 or P70, whereas there were no age-related changes in females. Adult females showed more locomotor activity than adult males. Overall, prenatal ethanol exposure on G15 enhanced social anxiety in females, with these effects seen in adulthood only. Copyright © 2013 Elsevier B.V. All rights reserved.

Acute and chronic in vivo effects of exposure to nicotine and propylene glycol from an E-cigarette on mucociliary clearance in a murine model.

PubMed

Laube, Beth L; Afshar-Mohajer, Nima; Koehler, Kirsten; Chen, Gang; Lazarus, Philip; Collaco, Joseph M; McGrath-Morrow, Sharon A

2017-04-01

To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. C57BL/6 male mice (age 10.5 ± 2.4 weeks) were exposed for 20 min/day to E-cigarette aerosol generated by a Joyetech 510-T ® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99m technetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6 ± 5.2%, 7.5 ± 2.8% and 11.2 ± 5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ± 8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ± 4.6)% (p < .05). Serum cotinine levels were <0.5 ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine.

Two cases of acute lead poisoning due to occupational exposure to lead.

PubMed

Ogawa, Masanori; Nakajima, Yoshiaki; Kubota, Ryuichi; Endo, Yoko

2008-04-01

We experienced two cases of acute lead poisoning due to occupational exposure to lead. The patients were engaged in stripping off antirust compounds including Pb from a bridge and re-painting it at the same work place. Both patients exhibited colic, arthralgia, and anemia. Blood lead levels were 73.1 microg/dl and 96.3 microg/dl. Intravenous CaEDTA chelation therapy was therefore performed. After chelation, blood lead levels decreased and symptoms gradually disappeared. Although the patients were working with protective equipment, the workplace was in the mountains and there was no water for washing. The patients were thus unable to washing their hands and faces. We assume that they swallowed lead dust left on their hands and faces when they removed their clothing, and believe that this poisoning occurred due to lack of knowledge sufficient for protection.

The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarapultseva, Elena I.

The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000 mGy of acute γ-rays. Exposure to 1000 and 10,000 mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F{sub 0} and F{sub 1}Daphniamore » gradually declined with the dose of parental exposure and significantly decreased at dose of 100 mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F{sub 0}Daphnia exposed to 1000 and 10,000 mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F{sub 2} total fertility was compromised only among progeny of parents that received the highest dose of 10,000 mGy. We propose that the decreased fertility observed among the F{sub 2} progeny of parents exposed to 10,000 mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F{sub 2} progeny of irradiated F{sub 0}Daphnia exposed to the lower doses of acute γ-rays. - Highlights: • Viability of irradiated daphnids and their F{sub 1} progeny is compromised. • Viability of the F{sub 2} progeny of irradiated parents is not affected. • Total fertility of irradiated daphnids and their F{sub 1} progeny declines with the dose. • Total fertility of the F{sub 2} progeny of parents exposed to 10,000 mGy is compromised. • The decreased fertility among the F{sub 2} progeny is transgenerational phenomenon.« less

Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident.

PubMed

Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

2015-05-01

Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Investigation of public exposure resulted from the radioiodine delay tank facility of nuclear medicine department

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yusof, Mohd Fahmi Mohd, E-mail: mfahmi@usm.my; Ali, Abdul Muhaimin Mat; Abdullah, Reduan

The study is carried out to assess the exposure rate that could contribute to public exposure in a radioiodine ward delay tank facility of Radiotherapy, Oncology and Nuclear Medicine, Department, Hospital Universiti Sains Malaysia (HUSM). The exposure rate at several locations including the delay tank room, doorway and at the public walking route was measured using Victoreen 415P-RYR survey meter. The radioactive level of the {sup 131}I waste was measured using Captus 3000 well counting system. The results showed that exposure rate and total count of the delay tank sample increased when the radioiodine ward was fully occupied with patientmore » and reduced when the ward was vacant. Occupancy of radioiodine ward for two consecutive weeks had dramatically increased the exposure rate around the delay tank and radioactive level of {sup 131}I waste. The highest exposure rate and radioactive level was recorded when the ward was occupied for two consecutive weeks with 177.00 µR/h and 58.36 kcpm respectively. The exposure rate decreased 15.76 % when the door of the delay tank room was closed. The exposure rate at public walking route decreased between 15.58 % and 36.92 % as the distance increased between 1 and 3 m.« less

Association between exposure to radiofrequency electromagnetic fields assessed by dosimetry and acute symptoms in children and adolescents: a population based cross-sectional study.

PubMed

Heinrich, Sabine; Thomas, Silke; Heumann, Christian; von Kries, Rüdiger; Radon, Katja

2010-11-25

The increase in numbers of mobile phone users was accompanied by some concern that exposure to radiofrequency electromagnetic fields (RF EMF) might adversely affect acute health especially in children and adolescents. The authors investigated this potential association using personal dosimeters. A 24-hour exposure profile of 1484 children and 1508 adolescents was generated in a population-based cross-sectional study in Germany between 2006 and 2008 (participation 52%). Personal interview data on socio-demographic characteristics, self-reported exposure and potential confounders were collected. Acute symptoms were assessed twice during the study day using a symptom diary. Only few of the large number of investigated associations were found to be statistically significant. At noon, adolescents with a measured exposure in the highest quartile during morning hours reported a statistically significant higher intensity of headache (Odd Ratio: 1.50; 95% confidence interval: 1.03, 2.19). At bedtime, adolescents with a measured exposure in the highest quartile during afternoon hours reported a statistically significant higher intensity of irritation in the evening (4th quartile 1.79; 1.23, 2.61), while children reported a statistically significant higher intensity of concentration problems (4th quartile 1.55; 1.02, 2.33). We observed few statistically significant results which are not consistent over the two time points. Furthermore, when the 10% of the participants with the highest exposure are taken into consideration the significant results of the main analysis could not be confirmed. Based on the pattern of these results, we assume that the few observed significant associations are not causal but rather occurred by chance.

Association between ambient noise exposure, hearing acuity, and risk of acute occupational injury

PubMed Central

Cantley, Linda F; Galusha, Deron; Cullen, Mark R; Dixon-Ernst, Christine; Rabinowitz, Peter M; Neitzel, Richard L

2015-01-01

Objective This study aimed to examine the associations between acute workplace injury risk, ambient noise exposure, and hearing acuity, adjusting for reported hearing protection use. Methods In a cohort of 9220 aluminum manufacturing workers studied over six years (33 300 person-years, 13 323 person-jobs), multivariate mixed effects models were used to estimate relative risk (RR) of all injuries as well as serious injuries by noise exposure category and hearing threshold level (HTL) adjusting for recognized and potential confounders. Results Compared to noise <82 dBA, higher exposure was associated with elevated risk in a monotonic and statistically significant exposure–response pattern for all injuries and serious injuries with higher risk estimates observed for serious injuries [82–84.99 dBA: RR 1.26, 95% confidence interval (95% CI) 0.96–1.64; 85–87.99 dBA: RR 1.39, 95% CI 1.05–1.85; ≥88 dBA: RR 2.29, 95% CI 1.52–3.47]. Hearing loss was associated with increased risk for all injuries, but was not a significant predictor of risk for the subset of more serious injuries. Compared to those without hearing loss, workers with HTL ≥25 dB had 21% increased all injury risk (RR 1.21, 95% CI 1.09–1.33) while those with HTL 10–24.99 dB had 6% increased risk (RR 1.06, 95% CI 1.00–1.13). Reported hearing protection type did not predict injury risk. Conclusion Noise exposure levels as low as 85 dBA may increase workplace injury risk. HTL was associated with increased risk for all, but not the subset of serious, injuries. Additional study is needed both to confirm the observed associations and explore causal pathways. PMID:25137556

Potential for a pluripotent adult stem cell treatment for acute radiation sickness

PubMed Central

Rodgerson, Denis O; Reidenberg, Bruce E; Harris, Alan G; Pecora, Andrew L

2012-01-01

Accidental radiation exposure and the threat of deliberate radiation exposure have been in the news and are a public health concern. Experience with acute radiation sickness has been gathered from atomic blast survivors of Hiroshima and Nagasaki and from civilian nuclear accidents as well as experience gained during the development of radiation therapy for cancer. This paper reviews the medical treatment reports relevant to acute radiation sickness among the survivors of atomic weapons at Hiroshima and Nagasaki, among the victims of Chernobyl, and the two cases described so far from the Fukushima Dai-Ichi disaster. The data supporting the use of hematopoietic stem cell transplantation and the new efforts to expand stem cell populations ex vivo for infusion to treat bone marrow failure are reviewed. Hematopoietic stem cells derived from bone marrow or blood have a broad ability to repair and replace radiation induced damaged blood and immune cell production and may promote blood vessel formation and tissue repair. Additionally, a constituent of bone marrow-derived, adult pluripotent stem cells, very small embryonic like stem cells, are highly resistant to ionizing radiation and appear capable of regenerating radiation damaged tissue including skin, gut and lung. PMID:24520532

Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poulsen, Sarah S., E-mail: spo@nrcwe.dk; Department of Science, Systems and Models, Roskilde University, DK-4000 Roskilde; Saber, Anne T., E-mail: ats@nrcwe.dk

Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162 μg/mouse of small, entangled (CNT{sub Small}, 0.8 ± 0.1 μm long) or large, thick MWCNTs (CNT{sub Large},more » 4 ± 0.4 μm long). Liver tissues and plasma were harvested 1, 3 and 28 days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects. The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3 levels correlated strongly with pulmonary Saa3 levels. Analysis of global gene expression revealed perturbation of the same biological processes and pathways in liver, including the HMG-CoA reductase pathway. Both MWCNTs induced similar histological hepatic changes, with a tendency towards greater response following CNT{sub Large} exposure. Overall, we show that pulmonary exposure to two different MWCNTs induces similar systemic and hepatic responses, including changes in plasma APR, lipid composition, hepatic gene expression and liver morphology. The results link pulmonary exposure to MWCNTs with risk of cardiovascular disease. - Highlights: • Systemic and hepatic alterations were evaluated in female mice following MWCNT instillation. • Despite being

Sensory and other neurogenic effects of exposures to airborne office dust

NASA Astrophysics Data System (ADS)

Mølhave, L.; Kjærgaard, S. K.; Attermann, J.

This Danish Office Dust Experiment investigated the response of 24 healthy non-sensitive adult subjects to exposure to normal office dust in the air (7 μg m -3 clean air, 136 and 390 μg m -3 TSP). The dust had no major identifiable specific reactive components. The exposure duration was 5 1/4 h and was arranged in a climate chamber in controlled atmospheric conditions. Measurements were made acutely at exposure onset, subacutely at exposure end and next day (late). As secondary aims the time course and threshold of any observed effect of the exposures, and the characteristics of any hyperresponding subgroup were investigated. In a questionnaire with 36 questions the dust exposures caused increased acute, subacute and late perceptions of reduced air quality, acute and subacute increased odor intensity, acute eye irritation, acute and late heavy head, subacute feeling of perspiration, and subacute general irritation. Cough increased subacutely during exposures. In addition, a performance test showed effects of dust exposures which also affected "Mood Scale" ratings. No effect was seen on an addition test for distraction, and objective measurements of skin humidity. The overall conclusion of the study is that healthy subjects without hypersensitivity reactions seem to respond to airborne house dust. The responses are both subjective sensory reactions and other neurogenic effects even at exposure levels within the range found in normal buildings. Some of the effects appeared acutely and decreased through adaptation while others increased during prolonged exposure and remained for more than 17 h after the exposure ended. The findings may indicate for this type of dust a threshold level for the dose-response relationships below 140 μg m -3.

Nuclear emulsion measurements of the astronauts' radiation exposure on the Apollo-Soyuz mission

NASA Technical Reports Server (NTRS)

Schaefer, H. J.; Sullivan, J. J.

1976-01-01

On the Apollo-Soyuz mission each astronaut carried one passive dosimeter containing nuclear photographic emulsions, plastic foils, TLD chips, and neutron-activation foils for recording radiation exposure. This report is limited to the presentation of data retrieved from nuclear emulsions. Protons, most of them trapped particles encountered in numerous passes through the South Atlantic Anomaly, contributed by far the largest share to the mission dose. Their linear energy transfer (LET) spectrum was established from track and grain counts in a G.5 emulsion which is used for medium and high energies, and from ender counts in a K.2 emulsion which is used for low energies. The total mission fluence of protons was found to be equivalent to a unidirectional beam of 448,500 square centimeters. The broad spectrum was broken down into small LET intervals, which allowed for the computation of absorbed doses and dose equivalents. The totals are 51 millirad and 74 millirem. Counts of disintegration stars in K.2 emulsion are incomplete at present. While a total of 467 stars were identified, counting their prong numbers is still in progress. It was concluded that the Apollo-Soyuz astronauts' radiation exposure as such did not contain anything out of the ordinary that would seem to require special attention.

Study of nuclear multifragmentation induced by ultrarelativistic μ-mesons in nuclear track emulsion

NASA Astrophysics Data System (ADS)

Artemenkov, D. A.; Bradnova, V.; Firu, E.; Kornegrutsa, N. K.; Haiduc, M.; Mamatkulov, K. Z.; Kattabekov, R. R.; Neagu, A.; Rukoyatkin, P. A.; Rusakova, V. V.; Stanoeva, R.; Zaitsev, A. A.; Zarubin, P. I.; Zarubina, I. G.

2016-02-01

Exposures of test samples of nuclear track emulsion were analyzed. The formation of high-multiplicity nuclear stars was observed upon irradiating nuclear track emulsions with ultrarelativistic muons. Kinematical features studied in this exposure of nuclear track emulsions for events of the muon-induced splitting of carbon nuclei to three α-particles are indicative of the nuclear-diffraction interaction mechanism.

Media's role in broadcasting acute stress following the Boston Marathon bombings.

PubMed

Holman, E Alison; Garfin, Dana Rose; Silver, Roxane Cohen

2014-01-07

We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), -2.36, 3.23], but lower nationwide when compared with Boston (b = -2.21; SE = 1.07; 95% CI, -4.31, -0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities.

Systemic Exposure to Thiopurines and Risk of Relapse in Children with Acute Lymphoblastic Leukemia: A Children’s Oncology Group Study

PubMed Central

Bhatia, Smita; Landier, Wendy; Hageman, Lindsey; Chen, Yanjun; Kim, Heeyoung; Sun, Can-Lan; Kornegay, Nancy; Evans, William E; Angiolillo, Anne L; Bostrom, Bruce; Casillas, Jacqueline; Lew, Glen; Maloney, Kelly W; Mascarenhas, Leo; Ritchey, A. Kim; Termuhlen, Amanda M; Carroll, William L; Wong, F Lennie; Relling, Mary V

2015-01-01

Importance Variability in prescribed 6-mercaptopurine and lack of adherence to 6-mercaptopurine could result in intra-individual variability in systemic exposure to 6-mercaptopurine (measured as erythrocyte thioguanine nucleotide levels) in children with acute lymphoblastic leukemia. The impact of intra-individual variability in systemic exposure to 6-mercaptopurine on relapse risk is unknown. Objective To determine impact of high intra-individual variability in 6-mercaptopurine systemic exposure on relapse risk in children with acute lymphoblastic leukemia. Design Prospective longitudinal design; daily adherence monitoring, 6-mercaptopurine dose-intensity and erythrocyte thioguanine nucleotide levels (pmol/8*10^8 erythrocytes) measured for 6 consecutive months per patient; cohort followed for a median of 6.7 years from diagnosis. Setting Children’s Oncology Group study (COG-AALL03N1); 94 participating institutions; ambulatory care setting. Participants Participants included 742 children meeting the following eligibility criteria: diagnosis of acute lymphoblastic leukemia at ≤21 years; in first continuous remission at study entry; receiving self/parent/caregiver-administered oral 6-mercaptopurine during maintenance. Median age at diagnosis: 5 years; 68% were male; 43% with NCI-based high-risk disease. Main Outcome Measures Adherence measured electronically using Medication Event Monitoring System that recorded date/time of each 6-mercaptopurine bottle opening; adherence rate defined as ratio of days of 6-mercaptopurine bottle opened to days when 6-mercaptopurine prescribed. 6-mercaptopurine doses actually prescribed were divided by planned protocol doses (75mg/m2/day) to compute average monthly dose-intensity. Electronically-monitored adherence (68,716 person-days), 6-mercaptopurine dose-intensity (120,439 person-days) and monthly erythrocyte thioguanine nucleotide levels (n=3,944 measurements) contributed to the analysis. Using intra-individual coefficients of

Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum.

PubMed

Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

2014-01-01

Growing awareness of cerebellar involvement in addiction is based on the cerebellum's intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

PubMed Central

Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

2014-01-01

Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

Reactive oxygen species produced by NADPH oxidase and mitochondrial dysfunction in lung after an acute exposure to Residual Oil Fly Ashes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Magnani, Natalia D.; Marchini, Timoteo; Vanasco, Virginia

2013-07-01

Reactive O{sub 2} species production triggered by particulate matter (PM) exposure is able to initiate oxidative damage mechanisms, which are postulated as responsible for increased morbidity along with the aggravation of respiratory diseases. The aim of this work was to quantitatively analyse the major sources of reactive O{sub 2} species involved in lung O{sub 2} metabolism after an acute exposure to Residual Oil Fly Ashes (ROFAs). Mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight), and lung samples were analysed 1 h after instillation. Tissue O{sub 2} consumption and NADPH oxidase (Nox) activity were evaluated in tissuemore » homogenates. Mitochondrial respiration, respiratory chain complexes activity, H{sub 2}O{sub 2} and ATP production rates, mitochondrial membrane potential and oxidative damage markers were assessed in isolated mitochondria. ROFA exposure was found to be associated with 61% increased tissue O{sub 2} consumption, a 30% increase in Nox activity, a 33% increased state 3 mitochondrial O{sub 2} consumption and a mitochondrial complex II activity increased by 25%. During mitochondrial active respiration, mitochondrial depolarization and a 53% decreased ATP production rate were observed. Neither changes in H{sub 2}O{sub 2} production rate, nor oxidative damage in isolated mitochondria were observed after the instillation. After an acute ROFA exposure, increased tissue O{sub 2} consumption may account for an augmented Nox activity, causing an increased O{sub 2}{sup ·−} production. The mitochondrial function modifications found may prevent oxidative damage within the organelle. These findings provide new insights to the understanding of the mechanisms involving reactive O{sub 2} species production in the lung triggered by ROFA exposure. - Highlights: • Exposure to ROFA alters the oxidative metabolism in mice lung. • The augmented Nox activity contributes to the high tissue O{sub 2} consumption. • Exposure to

Benzene and childhood acute leukemia in Oklahoma.

PubMed

Janitz, Amanda E; Campbell, Janis E; Magzamen, Sheryl; Pate, Anne; Stoner, Julie A; Peck, Jennifer D

2017-10-01

Although childhood cancer is a leading cause of childhood mortality in the US, evidence regarding the etiology is lacking. The goal of this study was to evaluate the association between benzene, a known carcinogen, and childhood acute leukemia. We conducted a case-control study including cases diagnosed with acute leukemia between 1997 and 2012 (n = 307) from the Oklahoma Central Cancer Registry and controls matched on week of birth from birth certificates (n = 1013). We used conditional logistic regression to evaluate the association between benzene, measured with the 2005 National-Scale Air Toxics Assessment (NATA) at census tract of the birth residence, and childhood acute leukemia. We observed no differences in benzene exposure overall between cases and controls. However, when stratified by year of birth, cases born from 2005 to 2010 had a three-fold increased unadjusted odds of elevated exposure compared to controls born in this same time period (4th Quartile OR: 3.53, 95% CI: 1.35, 9.27). Furthermore, the estimates for children with acute myeloid leukemia (AML) were stronger than those with acute lymphoid leukemia, though not statistically significant. While we did not observe an association between benzene and childhood leukemia overall, our results suggest that acute leukemia is associated with increased benzene exposure among more recent births, and children with AML may have increased benzene exposure at birth. Using the NATA estimates allowed us to assess a specific pollutant at the census tract level, providing an advantage over monitor or point source data. Our study, however, cannot rule out the possibility that benzene may be a marker of other traffic-related exposures and temporal misclassification may explain the lack of an association among earlier births. Copyright © 2017 Elsevier Inc. All rights reserved.

Limited Internal Radiation Exposure Associated with Resettlements to a Radiation-Contaminated Homeland after the Fukushima Daiichi Nuclear Disaster

PubMed Central

Tsubokura, Masaharu; Kato, Shigeaki; Nihei, Masahiko; Sakuma, Yu; Furutani, Tomoyuki; Uehara, Keisuke; Sugimoto, Amina; Nomura, Shuhei; Hayano, Ryugo; Kami, Masahiro; Watanobe, Hajime; Endo, Yukou

2013-01-01

Resettlement to their radiation-contaminated hometown could be an option for people displaced at the time of a nuclear disaster; however, little information is available on the safety implications of these resettlement programs. Kawauchi village, located 12–30 km southwest of the Fukushima Daiichi nuclear power plant, was one of the 11 municipalities where mandatory evacuation was ordered by the central government. This village was also the first municipality to organize the return of the villagers. To assess the validity of the Kawauchi villagers’ resettlement program, the levels of internal Cesium (Cs) exposures were comparatively measured in returnees, commuters, and non-returnees among the Kawauchi villagers using a whole body counter. Of 149 individuals, 5 villagers had traceable levels of Cs exposure; the median detected level was 333 Bq/body (range, 309–1050 Bq/kg), and 5.3 Bq/kg (range, 5.1–18.2 Bq/kg). Median annual effective doses of villagers with traceable Cs were 1.1 x 10-2 mSv/y (range, 1.0 x 10-2-4.1 x 10-2 mSv/y). Although returnees had higher chances of consuming locally produced vegetables, Cochran-Mantel-Haenszel test showed that their level of internal radiation exposure was not significantly higher than that in the other 2 groups (p=0.643). The present findings in Kawauchi village imply that it is possible to maintain internal radiation exposure at very low levels even in a highly radiation-contaminated region at the time of a nuclear disaster. Moreover, the risks for internal radiation exposure could be limited with a strict food control intervention after resettlement to the radiation-contaminated village. It is crucial to establish an adequate number of radio-contaminated testing sites within the village, to provide immediate test result feedback to the villagers, and to provide education regarding the importance of re-testing in reducing the risk of high internal radiation exposure. PMID:24312602

Limited internal radiation exposure associated with resettlements to a radiation-contaminated homeland after the Fukushima Daiichi nuclear disaster.

PubMed

Tsubokura, Masaharu; Kato, Shigeaki; Nihei, Masahiko; Sakuma, Yu; Furutani, Tomoyuki; Uehara, Keisuke; Sugimoto, Amina; Nomura, Shuhei; Hayano, Ryugo; Kami, Masahiro; Watanobe, Hajime; Endo, Yukou

2013-01-01

Resettlement to their radiation-contaminated hometown could be an option for people displaced at the time of a nuclear disaster; however, little information is available on the safety implications of these resettlement programs. Kawauchi village, located 12-30 km southwest of the Fukushima Daiichi nuclear power plant, was one of the 11 municipalities where mandatory evacuation was ordered by the central government. This village was also the first municipality to organize the return of the villagers. To assess the validity of the Kawauchi villagers' resettlement program, the levels of internal Cesium (Cs) exposures were comparatively measured in returnees, commuters, and non-returnees among the Kawauchi villagers using a whole body counter. Of 149 individuals, 5 villagers had traceable levels of Cs exposure; the median detected level was 333 Bq/body (range, 309-1050 Bq/kg), and 5.3 Bq/kg (range, 5.1-18.2 Bq/kg). Median annual effective doses of villagers with traceable Cs were 1.1 x 10(-2) mSv/y (range, 1.0 x 10(-2)-4.1 x 10(-2) mSv/y). Although returnees had higher chances of consuming locally produced vegetables, Cochran-Mantel-Haenszel test showed that their level of internal radiation exposure was not significantly higher than that in the other 2 groups (p=0.643). The present findings in Kawauchi village imply that it is possible to maintain internal radiation exposure at very low levels even in a highly radiation-contaminated region at the time of a nuclear disaster. Moreover, the risks for internal radiation exposure could be limited with a strict food control intervention after resettlement to the radiation-contaminated village. It is crucial to establish an adequate number of radio-contaminated testing sites within the village, to provide immediate test result feedback to the villagers, and to provide education regarding the importance of re-testing in reducing the risk of high internal radiation exposure.

Acute exposure to waterpipe tobacco smoke induces changes in the oxidative and inflammatory markers in mouse lung

PubMed Central

Khabour, Omar F.; Alzoubi, Karem H.; Bani-Ahmad, Mohammed; Dodin, Arwa; Eissenberg, Thomas; Shihadeh, Alan

2013-01-01

Context Tobacco smoking represents a global public health threat, claiming approximately 5 million lives a year. Waterpipe tobacco use has become popular particularly among youth in the past decade, buttressed by the perception that the waterpipe “filters” the smoke, rendering it less harmful than cigarette smoke. Objective In this study, we examined the acute exposure of waterpipe smoking on lung inflammation and oxidative stress in mice, and compared that to cigarette smoking. Materials and methods Mice were divided into three groups; fresh air control, cigarette and waterpipe. Animals were exposed to fresh air, cigarette, or waterpipe smoke using whole body exposure system one hour daily for 7 days. Results Both cigarette and waterpipe smoke exposure resulted in elevation of total white blood cell count, as well as absolute count of neutrophils, macrophages, and lymphocytes (P < 0.01). Both exposures also elevated proinflammatory markers such as TNF-α and IL-6 in BALF (P < 0.05), and oxidative stress markers including GPx activity in lungs (P < 0.05). Moreover, waterpipe smoke increased catalase activity in the lung (P < 0.05). However, none of the treatments altered IL-10 levels. Discussion and conclusion Results of cigarette smoking confirmed previous finding. Waterpipe results indicate that, similar to cigarettes, exposure to waterpipe tobacco smoke is harmful to the lungs. PMID:22906173

Postapplication Fipronil Exposure Following Use on Pets.

PubMed

Cochran, R C; Yu, Liu; Krieger, R I; Ross, J H

2015-01-01

Fipronil is a pyrazole acaricide and insecticide that may be used for insect, tick, lice, and mite control on pets. Residents' short-term and long-term postapplication exposures to fipronil, including secondary environmental exposures, were estimated using data from chemical-specific studies. Estimations of acute (24-h) absorbed doses for residents were based on U.S. Environmental Protection Agency (U.S. EPA) 2012 standard operating procedures (SOPs) for postapplication exposure. Chronic exposures were not estimated for residential use, as continuous, long-term application activities were unlikely to occur. Estimated acute postapplication absorbed doses were as high as 0.56 μg/kg-d for toddlers (1-2 yr) in households with treated pets based on current U.S. EPA SOPs. Acute toddler exposures estimated here were fivefold larger in comparison to adults. Secondary exposure from the household environment in which a treated pet lives that is not from contacting the pet, but from contacting the house interior to which pet residues were transferred, was estimated based on monitoring socks worn by pet owners. These secondary exposures were more than an order of magnitude lower than those estimated from contacting the pet and thus may be considered negligible.

Effects of acute chlorpyrifos exposure on in vivo acetylcholine accumulation in rat striatum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karanth, Subramanya; Liu, Jing; Mirajkar, Nikita

2006-10-01

This study examined the acute effects of chlorpyrifos (CPF) on cholinesterase inhibition and acetylcholine levels in the striatum of freely moving rats using in vivo microdialysis. Adult, male Sprague-Dawley rats were treated with vehicle (peanut oil, 2 ml/kg) or CPF (84, 156 or 279 mg/kg, sc) and functional signs of toxicity, body weight and motor activity recorded. Microdialysis was conducted at 1, 4 and 7 days after CPF exposure for measurement of acetylcholine levels in striatum. Rats were then sacrificed and the contralateral striatum and diaphragm were collected for biochemical measurements. Few overt signs of cholinergic toxicity were noted inmore » any rats. Body weight gain was significantly affected in the high-dose (279 mg/kg) group only, while motor activity (nocturnal rearing) was significantly reduced in all CPF-treated groups at one day (84 mg/kg) or from 1-4 days (156 and 279 mg/kg) after dosing. Cholinesterase activities in both diaphragm and striatum were markedly inhibited (50-92%) in a time-dependent manner, but there were relatively minimal dose-related changes. In contrast, time- and dose-dependent changes in striatal acetylcholine levels were noted, with significantly higher levels noted in the high-dose group compared to other groups. Maximal increases in striatal acetylcholine levels were observed at 4-7 days after dosing (84 mg/kg, 7-9-fold; 156 mg/kg, 10-13-fold; 279 mg/kg, 35-57-fold). Substantially higher acetylcholine levels were noted when an exogenous cholinesterase inhibitor was included in the perfusion buffer, but CPF treatment-related differences were substantially lower in magnitude under those conditions. The results suggest that marked differences in acetylcholine accumulation can occur with dosages of CPF eliciting relatively similar degrees of cholinesterase inhibition. Furthermore, the minimal expression of classic signs of cholinergic toxicity in the presence of extensive brain acetylcholine accumulation suggests that

Acute illnesses associated with exposure to fipronil--surveillance data from 11 states in the United States, 2001-2007.

PubMed

Lee, Soo-Jeong; Mulay, Prakash; Diebolt-Brown, Brienne; Lackovic, Michelle J; Mehler, Louise N; Beckman, John; Waltz, Justin; Prado, Joanne B; Mitchell, Yvette A; Higgins, Sheila A; Schwartz, Abby; Calvert, Geoffrey M

2010-08-01

Fipronil is a broad-spectrum phenylpyrazole insecticide widely used to control residential pests and is also commonly used for flea and tick treatment on pets. It is a relatively new insecticide and few human toxicity data exist on fipronil. This paper describes the magnitude and characteristics of acute illnesses associated with fipronil exposure. Illness cases associated with exposure to fipronil-containing products from 2001 to 2007 were identified from the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides Program and the California Department of Pesticide Regulation. A total of 103 cases were identified in 11 states. Annual case counts increased from 5 in 2001 to 30 in 2007. Of the cases, 55% were female, the median age was 37 years, and 11% were <15 years old. The majority (76%) had exposure in a private residence, 37% involved the use of pet-care products, and 26% had work-related exposures. Most cases (89%) had mild, temporary health effects. Neurological symptoms (50%) such as headache, dizziness, and paresthesia were the most common, followed by ocular (44%), gastrointestinal (28%), respiratory (27%), and dermal (21%) symptoms/signs. Exposures usually occurred from inadvertent spray/splash/spill of products or inadequate ventilation of the treated area before re-entry. Our findings indicate that exposure to fipronil can pose a risk for mild, temporary health effects in various body systems. Precautionary actions should be reinforced to prevent fipronil exposure to product users.

Toxicological responses of Laeonereis acuta (Polychaeta, Nereididae) after acute, subchronic and chronic exposure to cadmium.

PubMed

Dolagaratz Carricavur, Arantxa; Chiodi Boudet, Leila; Romero, María Belén; Polizzi, Paula; Marcovecchio, Jorge Eduardo; Gerpe, Marcela

2018-03-01

The objective of this study was to analyze the toxicological responses of the estuarine polychaete Laeonereis acuta after acute (96h), subchronic (7 days) and chronic (14 days) exposure to cadmium (Cd). Concentrations of metallothioneins (MT), lipid peroxidation (LPO), total Cd and metal-rich granules (MRG) were evaluated. Seasonal variations of MT and LPO levels in the wild were also measured. Polychaetes were obtained in the Quequén estuary located southeast of Buenos Aires Province, Argentina. For the acute toxicity assay, individuals were exposed to 10; 30, 65; 310; 600; 1300; 2000; 4300; 8100; 16300µgCdL -1 , which included levels of environmental relevance and median lethal concentrations (LC 50 ) for related species of polychaete. Based on 96h LC 50 values, polychaetes were exposed to sublethal doses of Cd. The concentrations for both subchronic and chronic assays were: 10; 30; 65; 310; 600; 1300; 2000; 4300µgCdL -1 . The 96h LC 50 value was 8234.9µgL -1 , which was within the values reported for other species of polychaete, indicating a high tolerance to Cd. MT induction was not observed for any time exposure. In additoin, LPO levels showed no differences with respect to control levels, which indicated an absence of oxidative damage caused by Cd. However, the total Cd and MRG-Cd concentrations in L. acuta in all tested treatments showed significant differences with respect to control levels. L. acuta were able to accumulate Cd in their tissues in the form of granules which are the main mechanism of Cd detoxification. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

PubMed

Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch-Góngora, Juan G; Galilea, Pedro A; Riera, Joan; Padial, Paulino

2014-01-01

When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest P(mean) obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max) (∼ 3%) and maximal strength (1 RM) (∼ 6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on P(mean) and P(peak) in the middle-high part of the curve (≥ 60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1 RM, movement velocity and power during the execution of a force-velocity curve in bench press.

Effect of Acute Exposure to Moderate Altitude on Muscle Power: Hypobaric Hypoxia vs. Normobaric Hypoxia

PubMed Central

Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch- Góngora, Juan G.; Galilea, Pedro A.; Riera, Joan; Padial, Paulino

2014-01-01

When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (∼3%) and maximal strength (1RM) (∼6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on Pmean and Ppeak in the middle-high part of the curve (≥60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1RM, movement velocity and power during the execution of a force-velocity curve in bench press. PMID:25474104

Acute and Subchronic Toxicity of Inhaled Toluene in Male ...

EPA Pesticide Factsheets

The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute and one subchronic, were conducted to seek effects of the VOC, toluene, in rats and to compare the effects between acute and subchronic exposures. Adult male Long-Evans rats were exposed to toluene vapor (n = 6 per group) at a concentration of 0 or l 019 ± 14 ppm for 6 h in the acute study and at 0 ± 0, 10 ± 1.4, 97 ± 7, or 995 ± 43 ppm for 6 h/d, 5 d/week for 13 weeksin the subchronic study. For the acute study, brains were dissected on ice within 30 min of the end of exposure, while for the subchronic study, brains were dissected 18 h after the last exposure. Frontal cortex, hippocampus, cerebellum, and striatum were assayed for a variety of oxidative stress (OS) parameters including total aconitase (TA), protein carbonyls, glutathione peroxidase (GPX), glutathione reductase (GRD), glutathione transferase (GST), y-­glutamylcysteine synthetase (GCS), superoxide dismutase (SOD), total antioxidants (TAS), NADPH quinone oxidoreductase- 1 (NQO1 ), and NADH ubiquinone reductase (UBIQ-RD) activities using commercially available kits. Following acute exposure, UBIQ-RD, GCS and GRD were increased significantly only in the cerebellum, while TAS was increased in frontal cortex. On the other

Sex and genetic differences in the effects of acute diesel exhaust exposure on inflammation and oxidative stress in mouse brain

PubMed Central

Cole, Toby B.; Coburn, Jacki; Dao, Khoi; Roqué, Pam; Chang, Yu-Chi; Kalia, Vrinda; Guilarte, Tomas R.; Dziedzic, Jennifer; Costa, Lucio G.

2016-01-01

In addition to increased morbidity and mortality caused by respiratory and cardiovascular diseases, air pollution may also contribute to central nervous system (CNS) diseases. Traffic-related air pollution is a major contributor to global air pollution, and diesel exhaust (DE) is its most important component. DE contains more than 40 toxic air pollutants and is a major constituent of ambient particulate matter (PM), particularly of ultrafine-PM. Limited information suggest that exposure to DE may cause oxidative stress and neuroinflammation in the CNS. We hypothesized that males may be more susceptible than females to DE neurotoxicity, because of a lower level of expression of paraoxonase 2 (PON2), an intracellular anti-oxidant and anti-inflammatory enzyme. Acute exposure of C57BL/6 mice to DE (250–300 µg/m3 for 6h) caused significant increases in lipid peroxidation and of pro-inflammatory cytokines (IL-1α, IL-1β, IL-3, IL-6, TNF-α) in various brain regions (particularly olfactory bulb and hippocampus). In a number of cases the observed effects were more pronounced in male than in female mice. DE exposure also caused microglia activation, as measured by increased Iba1 (ionized calcium-binding adapter molecule 1) expression, and of TSPO (translocator protein) binding. Mice heterozygotes for the modifier subunit of glutamate cysteine ligase (the limiting enzyme in glutathione biosynthesis; Gclm+/− mice) appeared to be significantly more susceptible to DE-induced neuroinflammation than wild type mice. These findings indicate that acute exposure to DE causes neuroinflammation and oxidative stress in brain, and suggests that sex and genetic background may play important roles in modulating susceptibility to DE neurotoxicity. PMID:27865893

Evaluation of the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira L. in rats.

PubMed

Bras, Cristina; Gumilar, Fernanda; Gandini, Norberto; Minetti, Alejandra; Ferrero, Adriana

2011-10-11

Schinus molle var. areira L. (Anacardiaceae) is employed in herbal medicine for many conditions, including respiratory, urinary and menstrual disorders, and as a digestive stimulant, diuretic, astringent and antidepressant. It is also known for its topical use as wound healer, antiseptic, for skin disorders and as repellent and insecticide. In the present work, the acute dermal exposure to ethanolic and hexanic extracts from leaves of Schinus molle var. areira was studied in rats. A single dose of 2000 mg/kg of body weight of ethanolic and hexanic extracts from leaves was applied on the shaved skin of male and female rats. After 24h of exposure, the patch was removed and any sign of irritation was recorded. Behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed after the exposure to the extracts. Then, after 14 days of observation, animals were retested. Finally, histopathological studies were conducted on several organs. Slight signs of erythema and edema were observed in the skin site of exposure, but they disappeared after 48 h. The exposure to the hexanic extract produced an increase in parameters of activity, rearing and arousal assessed in the functional observational battery, which reversed after 14 days. On the other hand, the ethanolic extract caused an increase in locomotor activity, reflected in a higher number of rearings performed in the open field in the evaluation carried out on Day 14. No histopathological alterations were detected in the analyzed organs. The results show that the acute dermal exposure of the ethanolic and hexanic extracts from leaves of Schinus molle var. areira only causes a slight and reversible skin irritation, and a mild stimulatory effect in rats. All these indicate that the topical use of these extracts would be safe. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Inhalation of diethylamine--acute nasal effects and subjective response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundqvist, G.R.; Yamagiwa, M.; Pedersen, O.F.

1992-03-01

Adult volunteers were exposed to 25 ppm (75 mg/m3) diethylamine in a climate chamber for 15 min in order to study the acute nasal reactions to an exposure equivalent to the present threshold limit value-short-term exposure limit. Changes in nasal volume and nasal resistance were measured by acoustic rhinometry and by rhinomanometry. Acute change in nasal volume, usually seen as acute nasal mucosa response to thermal stimuli, was not observed, nor was an acute change in nasal airway resistance. In a subsequent experiment, the aim was to measure acute sensory effects. Exposure to a concentration increasing from 0 to 12more » ppm took place for 60 min, equal to an average concentration of 10 ppm (30 mg/m3). A moderate to strong olfactory response and distinct nasal and eye irritation were observed. In spite of considerable individual variation, the results were in agreement with sensory effect estimates obtained from animal studies.« less

Residential radon exposure and adult acute leukaemia.

PubMed

Law, G R; Kane, E V; Roman, E; Smith, A; Cartwright, R

2000-05-27

Exposure to radioactive radon gas in homes, from natural sources, is an important public-health issue for many countries. We found no association between household exposure to radon and leukaemia in adults in the UK.

Contributing Factors for Acute Illness/Injury from Childhood Pesticide Exposure in North Carolina, USA, 2007–2013

PubMed Central

Barros, Nirmalla; Langley, Ricky; Buhler, Wayne; Brantham, Kelly

2016-01-01

Between 2007 and 2013, there were 685 events with evidence of a relationship between pesticide exposure and acute illness/injury among persons less than 18 years old in North Carolina (United States). Median age of children affected was 4.3 years (range: 0.2–17.9). Distribution by gender was similar across all age groups. One fatality and four high severity events were observed. The greatest proportion (42%) of events had ocular exposures, followed by dermal (25%) and inhalation (18%) exposures. When more than one route of exposure occurred, dermal and ocular routes were the most common (46%). Almost all events took place indoors and 32 events involved contact with pets. Insecticides (53%) and insect repellants (31%) were the most frequent agents contributing to these events. Manual application of pesticides contributed to the greatest number of events (25%), while application through a pressurized can and use of a trigger pump were involved in 21% and 15% of events, respectively. Additional contributors were due to inappropriate storage of pesticides and improper use of the pesticide. These contributing factors can be removed or minimized if pesticides are stored outside the residence or out of the reach of children and pets, and adequate ventilation is ensured whenever pesticides are applied. PMID:29051410

Estimating acute and chronic exposure of children and adults to chlorpyrifos in fruit and vegetables based on the new, lower toxicology data.

PubMed

Mojsak, Patrycja; Łozowicka, Bożena; Kaczyński, Piotr

2018-05-09

This paper presents, for the first time, results for chlorpyrifos (CHLP) in Polish fruits and vegetables over the course of a long period of research, 2007-2016, with toxicological aspects. The challenge of this study was to re-evaluate the impact of chlorpyrifos residues in fruit and vegetables on health risk assessed via acute and chronic exposure based on old and new, lower, established values of: Average Daily Intakes (ADIs)/Acute Reference Doses (ARfDs) and Maximum Residue Levels (MRLs). A total of 3 530 samples were collected, and CHLP in the range of 0.005-1.514 mg/kg was present in 10.2% of all samples. The MRL was exceeded in 0.7% of all samples (MRL established in 2009-2015), and recalculation yielded a much greater number of violations for the new MRL (2016), which exceeded 2.9% of all samples. Acute exposure to CHLP calculated according to the old, higher toxicological data (0.10 mg/kg bw/day), does not exceed 14% of its respective ARfDs for adults and both groups of children, but when calculated for incidental cases according to the current value (ARfD 0.005 mg/kg bw) for infants and toddlers, was above 100% of its respective ARfDs in: white cabbage (263.65% and 108.24%), broccoli (216.80% and 194.72%) and apples (153.20% and 167.70%). The chronic exposure calculated for both newly established ADI values (0.001 mg/kg bw/day and 0.100 mg/kg bw/day) appears to be relatively low for adults and children. Copyright © 2018 Elsevier Inc. All rights reserved.

Acute Exposure to Worst-Case Concentrations of Amitraz Does Not Affect Honey Bee Learning, Short-Term Memory, or Hemolymph Octopamine Levels.

PubMed

Rix, Rachel R; Christopher Cutler, G

2017-02-01

Amitraz, an acaricide used to treat Varroa destructor Anderson & Trueman, is one of the most commonly detected pesticides in honey bee (Apis mellifera L.) hives. Acaricides sometimes negatively impact honey bee cognition, but potential effects of amitraz on honey bee learning have been rarely studied. We topically exposed foragers to 95th percentile field-relevant levels of amitraz and, 24 h later, tested the ability of bees to associate a sucrose reward with a conditioned odor (learning response) using the proboscis extension response (PER). We then tested the ability of the bees to retain this memory 1 h and 2 h post-conditioning. Because amitraz is thought to affect octopamine metabolism in honey bees, and because octopamine is directly related to honey bee learning and memory, we also examined effects of exposure to amitraz on octopamine levels in honey bee hemolymph. We found that acute exposure to 95th percentile doses of amitraz had no impact on honey bee learning or short-term memory as measured by PER. Concentrations of octopamine in hemolymph from our low amitraz treatment were 1.4-fold higher than control levels, but other treatments had no effect. Our results from worst-case acute exposure experiments with worker bees in the laboratory suggest that typical field-relevant (within hive) exposures to amitraz probably have little effect on honey bee learning and memory. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fukushima Daiichi Nuclear Power Plant accident: facts, environmental contamination, possible biological effects, and countermeasures

PubMed Central

Anzai, Kazunori; Ban, Nobuhiko; Ozawa, Toshihiko; Tokonami, Shinji

2012-01-01

On March 11, 2011, an earthquake led to major problems at the Fukushima Daiichi Nuclear Power Plant. A 14-m high tsunami triggered by the earthquake disabled all AC power to Units 1, 2, and 3 of the Power Plant, and carried off fuel tanks for emergency diesel generators. Despite many efforts, cooling systems did not work and hydrogen explosions damaged the facilities, releasing a large amount of radioactive material into the environment. In this review, we describe the environmental impact of the nuclear accident, and the fundamental biological effects, acute and late, of the radiation. Possible medical countermeasures to radiation exposure are also discussed. PMID:22247595

Fukushima Daiichi Nuclear Power Plant accident: facts, environmental contamination, possible biological effects, and countermeasures.

PubMed

Anzai, Kazunori; Ban, Nobuhiko; Ozawa, Toshihiko; Tokonami, Shinji

2012-01-01

On March 11, 2011, an earthquake led to major problems at the Fukushima Daiichi Nuclear Power Plant. A 14-m high tsunami triggered by the earthquake disabled all AC power to Units 1, 2, and 3 of the Power Plant, and carried off fuel tanks for emergency diesel generators. Despite many efforts, cooling systems did not work and hydrogen explosions damaged the facilities, releasing a large amount of radioactive material into the environment. In this review, we describe the environmental impact of the nuclear accident, and the fundamental biological effects, acute and late, of the radiation. Possible medical countermeasures to radiation exposure are also discussed.

Association between exposure to radiofrequency electromagnetic fields assessed by dosimetry and acute symptoms in children and adolescents: a population based cross-sectional study

PubMed Central

2010-01-01

Background The increase in numbers of mobile phone users was accompanied by some concern that exposure to radiofrequency electromagnetic fields (RF EMF) might adversely affect acute health especially in children and adolescents. The authors investigated this potential association using personal dosimeters. Methods A 24-hour exposure profile of 1484 children and 1508 adolescents was generated in a population-based cross-sectional study in Germany between 2006 and 2008 (participation 52%). Personal interview data on socio-demographic characteristics, self-reported exposure and potential confounders were collected. Acute symptoms were assessed twice during the study day using a symptom diary. Results Only few of the large number of investigated associations were found to be statistically significant. At noon, adolescents with a measured exposure in the highest quartile during morning hours reported a statistically significant higher intensity of headache (Odd Ratio: 1.50; 95% confidence interval: 1.03, 2.19). At bedtime, adolescents with a measured exposure in the highest quartile during afternoon hours reported a statistically significant higher intensity of irritation in the evening (4th quartile 1.79; 1.23, 2.61), while children reported a statistically significant higher intensity of concentration problems (4th quartile 1.55; 1.02, 2.33). Conclusions We observed few statistically significant results which are not consistent over the two time points. Furthermore, when the 10% of the participants with the highest exposure are taken into consideration the significant results of the main analysis could not be confirmed. Based on the pattern of these results, we assume that the few observed significant associations are not causal but rather occurred by chance. PMID:21108839

Incubation Period and Early Natural History Events of the Acute Form of Paracoccidioidomycosis: Lessons from Patients with a Single Paracoccidioides spp. Exposure.

PubMed

Buccheri, Renata; Khoury, Zarifa; Barata, Luis Carlos Barradas; Benard, Gil

2016-06-01

Several aspects of the natural history of paracoccidioidomycosis are still poorly understood. Different from the most prevalent, chronic form of the disease, the acute form represents a continuum from the initial respiratory infection to the full-blown disease, thus providing an opportunity to elucidate the pathogenesis of the early phase of this mycosis. We describe, for the first time, two patients with a single time point exposure to Paracoccidioides spp., for whom we were able to determine the time lapsed between exposure to the fungus Paracoccidioides spp. and the onset of signs and symptoms. In case 1, the pulmonary infection was unapparent, and the first manifestations of the acute/subacute form of the disease presented 4 months after Paracoccidioides spp. In case 2, self-limited, non-specific respiratory and systemic symptoms presented 45 days after infection. Thus, our patients confirm that, within a few weeks of infection, Paracoccidioides spp. affects the pulmonary lymphatic system and initially causes no or mild-to-moderate self-limited symptoms, eventually causing abnormalities on a chest X-ray, all of which spontaneously subside. These cases provide some insight into the natural history of this mycosis, the extent of the host exposure to the fungus, and the determination of its incubation period.

Prolonged Particulate Hexavalent Chromium Exposure Suppresses Homologous Recombination Repair in Human Lung Cells

PubMed Central

Browning, Cynthia L.; Qin, Qin; Kelly, Deborah F.; Prakash, Rohit; Vanoli, Fabio; Jasin, Maria

2016-01-01

Abstract Genomic instability is one of the primary models of carcinogenesis and a feature of almost all cancers. Homologous recombination (HR) repair protects against genomic instability by maintaining high genomic fidelity during the repair of DNA double strand breaks. The defining step of HR repair is the formation of the Rad51 nucleofilament, which facilitates the search for a homologous sequence and invasion of the template DNA strand. Particulate hexavalent chromium (Cr(VI)), a human lung carcinogen, induces DNA double strand breaks and chromosome instability. Since the loss of HR repair increases Cr(VI)-induced chromosome instability, we investigated the effect of extended Cr(VI) exposure on HR repair. We show acute (24 h) Cr(VI) exposure induces a normal HR repair response. In contrast, prolonged (120 h) exposure to particulate Cr(VI) inhibited HR repair and Rad51 nucleofilament formation. Prolonged Cr(VI) exposure had a profound effect on Rad51, evidenced by reduced protein levels and Rad51 mislocalization to the cytoplasm. The response of proteins involved in Rad51 nuclear import and nucleofilament formation displayed varying responses to prolonged Cr(VI) exposure. BRCA2 formed nuclear foci after prolonged Cr(VI) exposure, while Rad51C foci formation was suppressed. These results suggest that particulate Cr(VI), a major chemical carcinogen, inhibits HR repair by targeting Rad51, causing DNA double strand breaks to be repaired by a low fidelity, Rad51-independent repair pathway. These results further enhance our understanding of the underlying mechanism of Cr(VI)-induced chromosome instability and thus, carcinogenesis. PMID:27449664

Acute toxicity and primary irritancy of alkylalkanolamines.

PubMed

Ballantyne, B; Leung, H W

1996-12-01

The acute handling hazards of several alkylalkanolamines were determined by investigating their potential acute toxicity and primary irritancy. Materials studied were N-methylethanolamine (MEA), N, N, -dimethylethanolamine (DMEA), N, N, -dimethylisopropanolamine (DMIPA), N-methyldiethanolamine (MDEA), and tertbutyldiethanolamine (BDEA). All these alkylalkanolamines were of comparable acute peroral toxicity in the rat (LD50 range 1.48-2.83 ml/kg). By 24 h occluded epicutaneous contact in the rabbit, MEA, DMEA and DMIPA were of moderate acute percutaneous toxicity (LD50 range 1.13-2.0 ml/kg), MDEA was of slight acute percutaneous toxicity (LD50 male 9.85 ml/kg, female 10.90 ml/kg), and BDEA of intermediate toxicity (LD50 6.4 ml/kg). Due to differences in vapor pressure the acute vapor exposure toxicity of the alkylalkanolamines to rats varied; MEA, MDEA and BDEA were of a low order of acute toxicity, and DMIPA was moderately toxic with an LT50 of 3.2 h for a saturated vapor atmosphere exposure. A 4 h-LC50 (rat combined sex) of 1461 ppm was determined for DMEA. All alkylalkanolamines studied, except MDEA, were moderately to markedly irritating and caused variable degrees of skin corrosivity; MDEA caused only transient minor skin irritation. In accord with the skin irritancy results, the eye irritancy from 0.005 ml MEA, DMEA, DMIPA and BDEA was severe, and that from MDEA was slight. Exposure to these compounds has implications for occupational health procedures.

Differential Effects of 5-HTTLPR Genotypes on Inhibition of Negative Emotional Information Following Acute Stress Exposure and Tryptophan Challenge

PubMed Central

Markus, C Rob; De Raedt, Rudi

2011-01-01

Previous data suggest that a polymorphism at the serotonin (5-HT) transporter gene (5-HTTLPR) may influence stress resilience and stress-related depression symptoms due to interactions between brain 5-HT dysfunction and stress exposure. Although attentional bias for emotional information has been reliably observed in depression, the interaction between 5-HT transporter-linked promoter region (5-HTTLPR), brain 5-HT vulnerability, and acute stress on affective information processing has not yet been investigated. This study examines the effects of tryptophan (TRP) augmentation (indicating 5-HT manipulation) on inhibition of negative emotional information under stress in mainly female S′/S′- vs L′/L′-allele carriers. A total of 15 female homozygotic short-allele 5-HTTLPR (S′/S′=S/S, S/LG, LG/LG) and 13 female homozygotic long-allele 5-HTTLPR (L′/L′=LA/LA) subjects were tested for mood and inhibition of emotional information in a double-blind, placebo-controlled design before and after stress exposure following TRP manipulation. Stress exposure significantly impaired inhibition of negative affective information only in S′/S′ carriers, whereas L′/L′ carriers even showed increased inhibition of negative information. The S′/S′ allele 5-HTTLPR genotype increases cognitive-attentional bias for negative emotional information under acute stress. As this bias is an important component of depression, this may be a mediating mechanism making S′/S′-allele carriers more vulnerability for stress-induced depression symptoms. Moreover, current data suggest that L′/L′-allele genotypes are more resilient, even increasing cognitive emotional (inhibitory) control after stress. PMID:21150915

Differential effects of 5-HTTLPR genotypes on inhibition of negative emotional information following acute stress exposure and tryptophan challenge.

PubMed

Markus, C Rob; De Raedt, Rudi

2011-03-01

Previous data suggest that a polymorphism at the serotonin (5-HT) transporter gene (5-HTTLPR) may influence stress resilience and stress-related depression symptoms due to interactions between brain 5-HT dysfunction and stress exposure. Although attentional bias for emotional information has been reliably observed in depression, the interaction between 5-HT transporter-linked promoter region (5-HTTLPR), brain 5-HT vulnerability, and acute stress on affective information processing has not yet been investigated. This study examines the effects of tryptophan (TRP) augmentation (indicating 5-HT manipulation) on inhibition of negative emotional information under stress in mainly female S'/S'- vs L'/L'-allele carriers. A total of 15 female homozygotic short-allele 5-HTTLPR (S'/S'=S/S, S/L(G), L(G)/L(G)) and 13 female homozygotic long-allele 5-HTTLPR (L'/L'=L(A)/L(A)) subjects were tested for mood and inhibition of emotional information in a double-blind, placebo-controlled design before and after stress exposure following TRP manipulation. Stress exposure significantly impaired inhibition of negative affective information only in S'/S' carriers, whereas L'/L' carriers even showed increased inhibition of negative information. The S'/S' allele 5-HTTLPR genotype increases cognitive-attentional bias for negative emotional information under acute stress. As this bias is an important component of depression, this may be a mediating mechanism making S'/S'-allele carriers more vulnerability for stress-induced depression symptoms. Moreover, current data suggest that L'/L'-allele genotypes are more resilient, even increasing cognitive emotional (inhibitory) control after stress.

Asian dust exposure triggers acute myocardial infarction.

PubMed

Kojima, Sunao; Michikawa, Takehiro; Ueda, Kayo; Sakamoto, Tetsuo; Matsui, Kunihiko; Kojima, Tomoko; Tsujita, Kenichi; Ogawa, Hisao; Nitta, Hiroshi; Takami, Akinori

2017-11-14

To elucidate whether Asian dust is associated with the incidence of acute myocardial infarction (AMI) and to clarify whether patients who are highly sensitive to Asian dust will develop AMI. Twenty-one participating institutions located throughout Kumamoto Prefecture and capable of performing coronary intervention were included in the study. Data for ground-level observations of Asian dust events were measured at the Kumamoto Local Meteorological Observatory. Data collected between 1 April 2010 and 31 March 2015 were analysed, and 3713 consecutive AMI patients were included. A time-stratified case-crossover design was applied to examine the association between Asian dust exposure and AMI. The occurrence of Asian dust events at 1 day before the onset of AMI was associated with the incidence of AMI [odds ratio (OR), 1.46; 95% confidence interval (CI), 1.09-1.95] and especially, non-ST-segment elevation myocardial infarction was significant (OR 2.03; 95% CI, 1.30-3.15). A significant association between AMI and Asian dust was observed in patients with age ≥75 years, male sex, hypertension, diabetes mellitus, never-smoking status, and chronic kidney disease (CKD). However, Asian dust events had a great impact on AMI onset in patients with CKD (P < 0.01). A scoring system accounting for several AMI risk factors was developed. The occurrence of Asian dust events was found to be significantly associated with AMI incidence among patients with a risk score of 5-6 (OR 2.45; 95% CI: 1.14-5.27). Asian dust events may lead to AMI and have a great impact on its onset in patients with CKD. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Amiodarone biokinetics, the formation of its major oxidative metabolite and neurotoxicity after acute and repeated exposure of brain cell cultures.

PubMed

Pomponio, Giuliana; Zurich, Marie-Gabrielle; Schultz, Luise; Weiss, Dieter G; Romanelli, Luca; Gramowski-Voss, Alexandra; Di Consiglio, Emma; Testai, Emanuela

2015-12-25

The difficulty in mimicking nervous system complexity and cell-cell interactions as well as the lack of kinetics information has limited the use of in vitro neurotoxicity data. Here, we assessed the biokinetic profile as well as the neurotoxicity of Amiodarone after acute and repeated exposure in two advanced rodent brain cell culture models, consisting of both neurons and glial cells organized in 2 or 3 dimensions to mimic the brain histiotypic structure and function. A strategy was applied to evidence the abiotic processes possibly affecting Amiodarone in vitro bioavailability, showing its ability to adsorb to the plastic devices. At clinically relevant Amiodarone concentrations, known to induce neurotoxicity in some patients during therapeutic treatment, a complete uptake was observed in both models in 24 h, after single exposure. After repeated treatments, bioaccumulation was observed, especially in the 3D cell model, together with a greater alteration of neurotoxicity markers. After 14 days, Amiodarone major oxidative metabolite (mono-N-desethylamiodarone) was detected at limited levels, indicating the presence of active drug metabolism enzymes (i.e. cytochrome P450) in both models. The assessment of biokinetics provides useful information on the relevance of in vitro toxicity data and should be considered in the design of an Integrated Testing Strategy aimed to identify specific neurotoxic alerts, and to improve the neurotoxicity assay predictivity for human acute and repeated exposure. Copyright © 2015 Elsevier Ltd. All rights reserved.

AltitudeOmics: cerebral autoregulation during ascent, acclimatization, and re-exposure to high altitude and its relation with acute mountain sickness.

PubMed

Subudhi, Andrew W; Fan, Jui-Lin; Evero, Oghenero; Bourdillon, Nicolas; Kayser, Bengt; Julian, Colleen G; Lovering, Andrew T; Panerai, Ronney B; Roach, Robert C

2014-04-01

Cerebral autoregulation (CA) acts to maintain brain blood flow despite fluctuations in perfusion pressure. Acute hypoxia is thought to impair CA, but it is unclear if CA is affected by acclimatization or related to the development of acute mountain sickness (AMS). We assessed changes in CA using transfer function analysis of spontaneous fluctuations in radial artery blood pressure (indwelling catheter) and resulting changes in middle cerebral artery blood flow velocity (transcranial Doppler) in 21 active individuals at sea level upon arrival at 5,260 m (ALT1), after 16 days of acclimatization (ALT16), and upon re-exposure to 5,260 m after 7 days at 1,525 m (POST7). The Lake Louise Questionnaire was used to evaluate AMS symptom severity. CA was impaired upon arrival at ALT1 (P < 0.001) and did not change with acclimatization at ALT16 or upon re-exposure at POST7. CA was not associated with AMS symptoms (all R < 0.50, P > 0.05). These findings suggest that alterations in CA are an intrinsic consequence of hypoxia and are not directly related to the occurrence or severity of AMS.

Media’s role in broadcasting acute stress following the Boston Marathon bombings

PubMed Central

Holman, E. Alison; Garfin, Dana Rose; Silver, Roxane Cohen

2014-01-01

We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), −2.36, 3.23], but lower nationwide when compared with Boston (b = −2.21; SE = 1.07; 95% CI, −4.31, −0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities. PMID:24324161

Association Between Early Postoperative Acetaminophen Exposure and Acute Kidney Injury in Pediatric Patients Undergoing Cardiac Surgery.

PubMed

Van Driest, Sara L; Jooste, Edmund H; Shi, Yaping; Choi, Leena; Darghosian, Leon; Hill, Kevin D; Smith, Andrew H; Kannankeril, Prince J; Roden, Dan M; Ware, Lorraine B

2018-05-14

Acute kidney injury (AKI) is a common and serious complication for pediatric cardiac surgery patients associated with increased morbidity, mortality, and length of stay. Current strategies focus on risk reduction and early identification because there are no known preventive or therapeutic agents. Cardiac surgery and cardiopulmonary bypass lyse erythrocytes, releasing free hemoglobin and contributing to oxidative injury. Acetaminophen may prevent AKI by reducing the oxidation state of free hemoglobin. To test the hypothesis that early postoperative acetaminophen exposure is associated with reduced risk of AKI in pediatric patients undergoing cardiac surgery. In this retrospective cohort study, the setting was 2 tertiary referral children's hospitals. The primary and validation cohorts included children older than 28 days admitted for cardiac surgery between July 1, 2008, and June 1, 2016. Exclusion criteria were postoperative extracorporeal membrane oxygenation and inadequate serum creatinine measurements to determine AKI status. Acetaminophen exposure in the first 48 postoperative hours. Acute kidney injury based on Kidney Disease: Improving Global Outcomes serum creatinine criteria (increase by ≥0.3 mg/dL from baseline or at least 1.5-fold more than the baseline [to convert to micromoles per liter, multiply by 88.4]) in the first postoperative week. The primary cohort (n = 666) had a median age of 6.5 (interquartile range [IQR], 3.9-44.7) months, and 341 (51.2%) had AKI. In unadjusted analyses, those with AKI had lower median acetaminophen doses than those without AKI (47 [IQR, 16-88] vs 78 [IQR, 43-104] mg/kg, P < .001). In logistic regression analysis adjusting for age, cardiopulmonary bypass time, red blood cell distribution width, postoperative hypotension, nephrotoxin exposure, and Risk Adjustment for Congenital Heart Surgery score, acetaminophen exposure was protective against postoperative AKI (odds ratio, 0.86 [95% CI, 0.82-0.90] per each

[Lung cancer in survivors of radiation exposure at the Chernobyl nuclear disaster].

PubMed

Zubovskiĭ, G A; Khrisanfov, S A

2003-01-01

Epidemiology, diagnostics and therapy of lung cancer in the aftermath of Chernobyl nuclear disaster are discussed on the basis of the data released by the Federal Expert Committee. Lung cancer appeared to be the main death-causing factor. The disease was far advanced (stage IIIb and IV) in 85% of cases. The effectiveness of diagnosis can be raised if such compulsory measures as annual bronchoscopic screenings and sputum counts are carried out. Atypical cell counts have to be run in the sputum samples from all the survivors who took part in the salvaging operations of 1986-1987 and are suffering acute and chronic respiratory diseases. Particular attention should be paid to those who were working under severe dust-pollution conditions in summer.

The risk of leukaemia in young children from exposure to tritium and carbon-14 in the discharges of German nuclear power stations and in the fallout from atmospheric nuclear weapons testing.

PubMed

Wakeford, Richard

2014-05-01

Towards the end of 2007, the results were published from a case-control study (the "KiKK Study") of cancer in young children, diagnosed <5 years of age during 1980-2003 while resident near nuclear power stations in western Germany. The study found a tendency for cases of leukaemia to live closer to the nearest nuclear power station than their matched controls, producing an odds ratio that was raised to a statistically significant extent for residence within 5 km of a nuclear power station. The findings of the study received much publicity, but a detailed radiological risk assessment demonstrated that the radiation doses received by young children from discharges of radioactive material from the nuclear reactors were much lower than those received from natural background radiation and far too small to be responsible for the statistical association reported in the KiKK Study. This has led to speculation that conventional radiological risk assessments have grossly underestimated the risk of leukaemia in young children posed by exposure to man-made radionuclides, and particular attention has been drawn to the possible role of tritium and carbon-14 discharges in this supposedly severe underestimation of risk. Both (3)H and (14)C are generated naturally in the upper atmosphere, and substantial increases in these radionuclides in the environment occurred as a result of their production by atmospheric testing of nuclear weapons during the late 1950s and early 1960s. If the leukaemogenic effect of these radionuclides has been seriously underestimated to the degree necessary to explain the KiKK Study findings, then a pronounced increase in the worldwide incidence of leukaemia among young children should have followed the notably elevated exposure to (3)H and (14)C from nuclear weapons testing fallout. To investigate this hypothesis, the time series of incidence rates of leukaemia among young children <5 years of age at diagnosis has been examined from ten cancer registries

Is the tobacco control movement misrepresenting the acute cardiovascular health effects of secondhand smoke exposure? An analysis of the scientific evidence and commentary on the implications for tobacco control and public health practice

PubMed Central

Siegel, Michael

2007-01-01

While chronic exposure to secondhand smoke has been well recognized as a cause of heart disease in nonsmokers, there has been recent speculation about the potential acute cardiovascular effects of transient exposure to secondhand smoke among nonsmokers; in particular, the possibility that such exposure could increase the risk of acute myocardial infarction even in an otherwise healthy nonsmoker. This paper reviews the claims being made by a number of anti-smoking and public health groups regarding the acute cardiovascular effects of secondhand smoke exposure among otherwise healthy adults, analyzes the validity of these claims based on a review of the scientific evidence, and discusses the implications of the findings for tobacco control and public health practice. Based on the analysis, it appears that a large number of anti-smoking organizations are making inaccurate claims that a single, acute, transient exposure to secondhand smoke can cause severe and even fatal cardiovascular events in healthy nonsmokers. The dissemination of inaccurate information by anti-smoking groups to the public in support of smoking bans is unfortunate because it may harm the tobacco control movement by undermining its credibility, reputation, and effectiveness. Disseminating inaccurate information also represents a violation of basic ethical principles that are a core value of public health practice that cannot and should not be sacrificed, even for a noble end such as protecting nonsmokers from secondhand smoke exposure. How the tobacco control movement responds to this crisis of credibility will go a long way towards determining the future effectiveness of the movement and its ability to continue to save lives and protect the public's health. PMID:17927828

Assessment of environmental public exposure from a hypothetical nuclear accident for Unit-1 Bushehr nuclear power plant.

PubMed

Sohrabi, M; Ghasemi, M; Amrollahi, R; Khamooshi, C; Parsouzi, Z

2013-05-01

Unit-1 of the Bushehr nuclear power plant (BNPP-1) is a VVER-type reactor with 1,000-MWe power constructed near Bushehr city at the coast of the Persian Gulf, Iran. The reactor has been recently operational to near its full power. The radiological impact of nuclear power plant (NPP) accidents is of public concern, and the assessment of radiological consequences of any hypothetical nuclear accident on public exposure is vital. The hypothetical accident scenario considered in this paper is a design-basis accident, that is, a primary coolant leakage to the secondary circuit. This scenario was selected in order to compare and verify the results obtained in the present paper with those reported in the Final Safety Analysis Report (FSAR 2007) of the BNPP-1 and to develop a well-proven methodology that can be used to study other and more severe hypothetical accident scenarios for this reactor. In the present study, the version 2.01 of the PC COSYMA code was applied. In the early phase of the accidental releases, effective doses (from external and internal exposures) as well as individual and collective doses (due to the late phase of accidental releases) were evaluated. The surrounding area of the BNPP-1 within a radius of 80 km was subdivided into seven concentric rings and 16 sectors, and distribution of population and agricultural products was calculated for this grid. The results show that during the first year following the modeled hypothetical accident, the effective doses do not exceed the limit of 5 mSv, for the considered distances from the BNPP-1. The results obtained in this study are in good agreement with those in the FSAR-2007 report. The agreement obtained is in light of many inherent uncertainties and variables existing in the two modeling procedures applied and proves that the methodology applied here can also be used to model other severe hypothetical accident scenarios of the BNPP-1 such as a small and large break in the reactor coolant system as well

Social identity influences stress appraisals and cardiovascular reactions to acute stress exposure.

PubMed

Gallagher, Stephen; Meaney, Sarah; Muldoon, Orla T

2014-09-01

This study tested a recent theoretical development in stress research to see whether group membership influenced cardiovascular reactions following exposure to acute stress. Participants (N = 104) were exposed to a message in which a maths test was described as stressful or challenging by an ingroup member (a student) or outgroup member (a stress disorder sufferer). Systolic blood pressure and diastolic blood pressure(DBP) and heart rate (HR) were monitored throughout a standard reactivity study. As expected, a significant interaction was found; relative to those who were told that the task was challenging, ingroup members reported more stress and had higher DBP and HR reactivity when told by an ingroup member that the maths task was stressful; task information did not have the same effect for outgroup members. These results indicate that informational support is not constant but varies as a function of group membership. Finally, this recent development in stress research may prove useful for those interested in investigating the interactions between social, psychological and physiological processes underlying health disparities. What is already known on this subject? Stress is a common risk factor for hypertension and coronary heart disease. Social support has been found to reduce cardiovascular reactions to acute psychological stress. The influence of social support on stress varies as a consequence of social identity. What does this study add? The social group that one belongs to influences how one appraises and responds to stress. Social identity provides a useful framework for understanding how social processes are associated with health disparities. © 2013 The British Psychological Society.

In Vitro Dermal Safety Assessment of Silver Nanowires after Acute Exposure: Tissue vs. Cell Models

PubMed Central

Grichine, Alexei; Rachidi, Walid; Charlet, Laurent

2018-01-01

Silver nanowires (AgNW) are attractive materials that are anticipated to be incorporated into numerous consumer products such as textiles, touchscreen display, and medical devices that could be in direct contact with skin. There are very few studies on the cellular toxicity of AgNW and no studies that have specifically evaluated the potential toxicity from dermal exposure. To address this question, we investigated the dermal toxicity after acute exposure of polymer-coated AgNW with two sizes using two models, human primary keratinocytes and human reconstructed epidermis. In keratinocytes, AgNW are rapidly and massively internalized inside cells leading to dose-dependent cytotoxicity that was not due to Ag+ release. Analysing our data with different dose metrics, we propose that the number of NW is the most appropriate dose-metric for studies of AgNW toxicity. In reconstructed epidermis, the results of a standard in vitro skin irritation assay classified AgNW as non-irritant to skin and we found no evidence of penetration into the deeper layer of the epidermis. The findings show that healthy and intact epidermis provides an effective barrier for AgNW, although the study does not address potential transport through follicles or injured skin. The combined cell and tissue model approach used here is likely to provide an important methodology for assessing the risks for skin exposure to AgNW from consumer products. PMID:29641466

In Vitro Dermal Safety Assessment of Silver Nanowires after Acute Exposure: Tissue vs. Cell Models.

PubMed

Lehmann, Sylvia G; Gilbert, Benjamin; Maffeis, Thierry Gg; Grichine, Alexei; Pignot-Paintrand, Isabelle; Clavaguera, Simon; Rachidi, Walid; Seve, Michel; Charlet, Laurent

2018-04-11

Silver nanowires (AgNW) are attractive materials that are anticipated to be incorporated into numerous consumer products such as textiles, touchscreen display, and medical devices that could be in direct contact with skin. There are very few studies on the cellular toxicity of AgNW and no studies that have specifically evaluated the potential toxicity from dermal exposure. To address this question, we investigated the dermal toxicity after acute exposure of polymer-coated AgNW with two sizes using two models, human primary keratinocytes and human reconstructed epidermis. In keratinocytes, AgNW are rapidly and massively internalized inside cells leading to dose-dependent cytotoxicity that was not due to Ag⁺ release. Analysing our data with different dose metrics, we propose that the number of NW is the most appropriate dose-metric for studies of AgNW toxicity. In reconstructed epidermis, the results of a standard in vitro skin irritation assay classified AgNW as non-irritant to skin and we found no evidence of penetration into the deeper layer of the epidermis. The findings show that healthy and intact epidermis provides an effective barrier for AgNW, although the study does not address potential transport through follicles or injured skin. The combined cell and tissue model approach used here is likely to provide an important methodology for assessing the risks for skin exposure to AgNW from consumer products.

Predictive acute toxicity tests with pesticides.

PubMed

Brown, V K

1983-01-01

By definition pesticides are biocidal products and this implies a probability that pesticides may be acutely toxic to species other than the designated target species. The ways in which pesticides are manufactured, formulated, packaged, distributed and used necessitates a potential for the exposure of non-target species although the technology exists to minimize adventitious exposure. The occurrence of deliberate exposure of non-target species due to the misuse of pesticides is known to happen. The array of predictive acute toxicity tests carried out on pesticides and involving the use of laboratory animals can be justified as providing data on which hazard assessment can be based. This paper addresses the justification and rationale of this statement.

Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

PubMed Central

Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

1997-01-01

OBJECTIVES: Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. METHODS: A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. RESULTS: Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. CONCLUSIONS: Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours. PMID:9155782

Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

PubMed

Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

1997-03-01

Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours.

Extensive review of fish embryo acute toxicities for the prediction of GHS acute systemic toxicity categories.

PubMed

Scholz, Stefan; Ortmann, Julia; Klüver, Nils; Léonard, Marc

2014-08-01

Distribution and marketing of chemicals require appropriate labelling of health, physical and environmental hazards according to the United Nations global harmonisation system (GHS). Labelling for (human) acute toxicity categories is based on experimental findings usually obtained by oral, dermal or inhalative exposure of rodents. There is a strong societal demand for replacing animal experiments conducted for safety assessment of chemicals. Fish embryos are considered as alternative to animal testing and are proposed as predictive model both for environmental and human health effects. Therefore, we tested whether LC50s of the fish embryo acute toxicity test would allow effectively predicting of acute mammalian toxicity categories. A database of published fish embryo LC50 containing 641 compounds was established. For these compounds corresponding rat oral LD50 were identified resulting in 364 compounds for which both fish embryo LC50 and rat LD50 was available. Only a weak correlation of fish embryo LC50 and rat oral LD50 was obtained. Fish embryos were also not able to effectively predict GHS oral acute toxicity categories. We concluded that due to fundamental exposure protocol differences (single oral dose versus water-borne exposure) a reverse dosimetry approach is needed to explore the predictive capacity of fish embryos. Copyright © 2014 Elsevier Inc. All rights reserved.

Mortality among workers monitored for radiation exposure at the French nuclear fuel company.

PubMed

Metz-Flamant, C; Rogel, A; Caër, S; Samson, E; Laurier, D; Acker, A; Tirmarche, M

2009-01-01

A cohort of 9,285 nuclear workers employed at the French company AREVA NC specializing in the nuclear fuel cycle was established. Vital status, causes of death, employment characteristics and annual exposure to ionizing radiation were reconstructed for each individual over the time period 1977-2004. Standardized mortality ratios (SMRs) were computed using national mortality rates as an external reference. Tests for trends in mortality with duration of employment and cumulative external dose were performed. The all-cause and all-cancer mortality was significantly lower than expected from the French population. No significant excess among cancer sites studied was observed. Significant positive trends with cumulative dose were observed for colon and liver cancer and for respiratory diseases. Isolated significant trends should be carefully interpreted and considered in line with the large number of trend tests performed.

Gene expression changes in female zebrafish (Danio rerio) brain in response to acute exposure to methylmercury

USGS Publications Warehouse

Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

2011-01-01

Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 h) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5(mu or u)g MeHg/g. Gene expression changes in the brain were examined using a 22,000-feature zebrafish microarray. At a significance level of pexposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and will investigate responsive genes as potential biomarkers of MeHg exposure.

The genomic transcriptional response of female fathead minnows (Pimephales promelas) to an acute exposure to the androgen, 17β-trenbolone

USGS Publications Warehouse

Dorts, Jennifer; Richter, Catherine A.; Wright-Osment, Maureen K.; Ellersieck, Mark R.; Carter, Barbara J.; Tillitt, Donald E.

2009-01-01

We investigated the genomic transcriptional response of female fathead minnows (Pimephales promelas) to an acute (4 days) exposure to 0.1 or 1.0 ??g/L of 17??-trenbolone (TB), the active metabolite of an anabolic androgenic steroid used as a growth promoter in cattle and a contaminant of concern in aquatic systems. Our objectives were to investigate the gene expression profile induced by TB, define biomarkers of exposure to TB, and increase our understanding of the mechanisms of adverse effects of TB on fish reproduction. In female gonad tissue, microarray analysis using a 22 K oligonucleotide microarray (EcoArray Inc., Gainesville, FL) showed 99 significantly upregulated genes and 741 significantly downregulated genes in response to 1 ??g TB/L. In particular, hydroxysteroid (17??) dehydrogenase 12a (hsd17b12a), zona pellucida glycoprotein 2.2 (zp2.2), and protein inhibitor of activated STAT, 2 (pias2) were all downregulated in gonad. Q-PCR measurements in a larger sample set were consistent with the microarray results in the direction and magnitude of these changes in gene expression. However, several novel potential biomarkers were verified by Q-PCR in the same samples, but could not be validated in independent samples. In liver, Q-PCR measurements showed a significant decrease in vitellogenin 1 (vtg1) mRNA expression. In brain, cytochrome P450, family 19, subfamily A, polypeptide 1b (cyp19a1b, previously known as aromatase B) transcript levels were significantly reduced following TB exposure. Our study provides a candidate gene involved in mediating the action of TB, hsd17b12a, and two potential biomarkers sensitive to acute TB exposure, hepatic vtg1 and brain cyp19a1b.

Sex and genetic differences in the effects of acute diesel exhaust exposure on inflammation and oxidative stress in mouse brain.

PubMed

Cole, Toby B; Coburn, Jacki; Dao, Khoi; Roqué, Pam; Chang, Yu-Chi; Kalia, Vrinda; Guilarte, Tomas R; Dziedzic, Jennifer; Costa, Lucio G

2016-12-30

In addition to increased morbidity and mortality caused by respiratory and cardiovascular diseases, air pollution may also contribute to central nervous system (CNS) diseases. Traffic-related air pollution is a major contributor to global air pollution, and diesel exhaust (DE) is its most important component. DE contains more than 40 toxic air pollutants and is a major constituent of ambient particulate matter (PM), particularly of ultrafine-PM. Limited information suggests that exposure to DE may cause oxidative stress and neuroinflammation in the CNS. We hypothesized that males may be more susceptible than females to DE neurotoxicity, because of a lower level of expression of paraoxonase 2 (PON2), an intracellular anti-oxidant and anti-inflammatory enzyme. Acute exposure of C57BL/6 mice to DE (250-300μg/m 3 for 6h) caused significant increases in lipid peroxidation and of pro-inflammatory cytokines (IL-1α, IL-1β, IL-3, IL-6, TNF-α) in various brain regions (particularly olfactory bulb and hippocampus). In a number of cases the observed effects were more pronounced in male than in female mice. DE exposure also caused microglia activation, as measured by increased Iba1 (ionized calcium-binding adapter molecule 1) expression, and of TSPO (translocator protein) binding. Mice heterozygotes for the modifier subunit of glutamate cysteine ligase (the limiting enzyme in glutathione biosynthesis; Gclm +/- mice) appeared to be significantly more susceptible to DE-induced neuroinflammation than wild type mice. These findings indicate that acute exposure to DE causes neuroinflammation and oxidative stress in brain, and suggest that sex and genetic background may play important roles in modulating susceptibility to DE neurotoxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

CATEGORICAL REGRESSION ANALYSIS OF ACUTE INHALATION TOXICITY DATA FOR HYDROGEN SULFIDE

EPA Science Inventory

Categorical regression is one of the tools offered by the U.S. EPA for derivation of acute reference exposures (AREs), which are dose-response assessments for acute exposures to inhaled chemicals. Categorical regression is used as a meta-analytical technique to calculate probabi...

Early Exposure to Recommended Calorie Delivery in the Intensive Care Unit Is Associated With Increased Mortality in Patients With Acute Respiratory Distress Syndrome.

PubMed

Peterson, Sarah J; Lateef, Omar B; Freels, Sally; McKeever, Liam; Fantuzzi, Giamila; Braunschweig, Carol A

2017-06-01

The Intensive Nutrition in Acute Lung Injury: Clinical Trial (INTACT), designed to evaluate outcomes of calorie delivery from acute respiratory distress syndrome (ARDS) diagnosis through hospital discharge, was stopped due to higher mortality in the intervention group. Post hoc analysis found timing and dose of calorie delivery influenced mortality. The objective of this retrospective cohort study was to determine if early vs late calorie exposure changed the hazard of death among a larger sample of patients with ARDS. Adult patients who met the eligibility criteria for INTACT but did not participate were included. Daily calorie delivery was collected from the date INTACT eligibility was determined to extubation or death. Cox proportional hazards regression was used to model the relationship between hazard of hospital death with average calorie exposure received over increasing study days and after day 7. A total of 298 patients were included; overall mortality was 33%. Among patients who remained intubated at 1 week (n = 202), higher kcal/kg received from intensive care unit (ICU) days 1-6 increased hazards of subsequent death on days 7+ (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.06); kcal/kg received after ICU day 7 decreased the hazards of death on day 7+ (HR, 0.53; 95% CI, 0.33-0.84). Higher calorie exposure between ICU days 1 and 7 was associated with higher subsequent hazard of mortality, and provision of high-calorie exposure after day 8 decreased the hazards of death.

Radiological protection from radioactive waste management in existing exposure situations resulting from a nuclear accident.

PubMed

Sugiyama, Daisuke; Hattori, Takatoshi

2013-01-01

In environmental remediation after nuclear accidents, radioactive wastes have to be appropriately managed in existing exposure situations with contamination resulting from the emission of radionuclides by such accidents. In this paper, a framework of radiation protection from radioactive waste management in existing exposure situations for application to the practical and reasonable waste management in contaminated areas, referring to related ICRP recommendations was proposed. In the proposed concept, intermediate reference levels for waste management are adopted gradually according to the progress of the reduction in the existing ambient dose in the environment on the basis of the principles of justification and optimisation by taking into account the practicability of the management of radioactive waste and environmental remediation. It is essential to include the participation of relevant stakeholders living in existing exposure situations in the selection of reference levels for the existing ambient dose and waste management.

Radiological protection from radioactive waste management in existing exposure situations resulting from a nuclear accident

PubMed Central

Sugiyama, Daisuke; Hattori, Takatoshi

2013-01-01

In environmental remediation after nuclear accidents, radioactive wastes have to be appropriately managed in existing exposure situations with contamination resulting from the emission of radionuclides by such accidents. In this paper, a framework of radiation protection from radioactive waste management in existing exposure situations for application to the practical and reasonable waste management in contaminated areas, referring to related ICRP recommendations was proposed. In the proposed concept, intermediate reference levels for waste management are adopted gradually according to the progress of the reduction in the existing ambient dose in the environment on the basis of the principles of justification and optimisation by taking into account the practicability of the management of radioactive waste and environmental remediation. It is essential to include the participation of relevant stakeholders living in existing exposure situations in the selection of reference levels for the existing ambient dose and waste management. PMID:22719047

An enriched stable-isotope approach to determine the gill-zinc binding properties of juvenile rainbow trout (Oncorhynchus mykiss) during acute zinc exposures in hard and soft waters

USGS Publications Warehouse

Todd, A.S.; Brinkman, S.; Wolf, R.E.; Lamothe, P.J.; Smith, K.S.; Ranville, J.F.

2009-01-01

The objective of the present study was to employ an enriched stable-isotope approach to characterize Zn uptake in the gills of rainbow trout (Oncorhynchus mykiss) during acute Zn exposures in hard water (???140 mg/L as CaCO 3) and soft water (???30 mg/L as CaCO3). Juvenile rainbow trout were acclimated to the test hardnesses and then exposed for up to 72 h in static exposures to a range of Zn concentrations in hard water (0-1,000 ??g/L) and soft water (0-250 ??g/L). To facilitate detection of new gill Zn from endogenous gill Zn, the exposure media was significantly enriched with 67Zn stable isotope (89.60% vs 4.1% natural abundance). Additionally, acute Zn toxicity thresholds (96-h median lethal concentration [LC50]) were determined experimentally through traditional, flow-through toxicity tests in hard water (580 ??g/L) and soft water (110 ??g/L). Following short-term (???3 h) exposures, significant differences in gill accumulation of Zn between hard and soft water treatments were observed at the three common concentrations (75, 150, and 250 ??g/L), with soft water gills accumulating more Zn than hard water gills. Short-term gill Zn accumulation at hard and soft water LC50s (45-min median lethal accumulation) was similar (0.27 and 0.20 ??g/g wet wt, respectively). Finally, comparison of experimental gill Zn accumulation, with accumulation predicted by the biotic ligand model, demonstrated that model output reflected short-term (<1 h) experimental gill Zn accumulation and predicted observed differences in accumulation between hard and soft water rainbow trout gills. Our results indicate that measurable differences exist in short-term gill Zn accumulation following acclimation and exposure in different water hardnesses and that short-term Zn accumulation appears to be predictive of Zn acute toxicity thresholds (96-h LC50s). ?? 2009 SETAC.

Acute diesel exhaust particle exposure increases viral titre and inflammation associated with existing influenza infection, but does not exacerbate deficits in lung function

PubMed Central

Larcombe, Alexander N.; Foong, Rachel E.; Boylen, Catherine E.; Zosky, Graeme R.

2012-01-01

Please cite this paper as: Larcombe et al. (2012) Acute diesel exhaust particle exposure increases viral titre and inflammation associated with existing influenza infection, but does not exacerbate deficits in lung function. Influenza and Other Respiratory Viruses DOI:10.1111/irv.12012. Background  Exposure to diesel exhaust particles (DEP) is thought to exacerbate many pre‐existing respiratory diseases, including asthma, bronchitis and chronic obstructive pulmonary disease, however, there is a paucity of data on whether DEP exacerbates illness due to respiratory viral infection. Objectives  To assess the physiological consequences of an acute DEP exposure during the peak of influenza‐induced illness. Methods  We exposed adult female BALB/c mice to 100 μg DEP (or control) 3·75 days after infection with 104·5 plaque forming units of influenza A/Mem71 (or control). Six hours, 24 hours and 7 days after DEP exposure we measured thoracic gas volume and lung function at functional residual capacity. Bronchoalveolar lavage fluid was taken for analyses of cellular inflammation and cytokines, and whole lungs were taken for measurement of viral titre. Results  Influenza infection resulted in significantly increased inflammation, cytokine influx and impairment to lung function. DEP exposure alone resulted in less inflammation and cytokine influx, and no impairment to lung function. Mice infected with influenza and exposed to DEP had higher viral titres and neutrophilia compared with infected mice, yet they did not have more impaired lung mechanics than mice infected with influenza alone. Conclusions  A single dose of DEP is not sufficient to physiologically exacerbate pre‐existing respiratory disease caused by influenza infection in mice. PMID:22994877

Acute hydrogen peroxide (H2O2) exposure does not cause oxidative stress in late-copepodite stage of Calanus finmarchicus.

PubMed

Hansen, Bjørn Henrik; Hallmann, Anna; Altin, Dag; Jenssen, Bjørn Munro; Ciesielski, Tomasz M

2017-01-01

Use of hydrogen peroxide (H 2 O 2 ) for removal of salmon lice in the aquaculture industry has created concern that non-target organisms might be affected during treatment scenarios. The aim of the present study was to examine the potential for H 2 O 2 to produce oxidative stress and reduce survival in one of the most abundant zooplankton species in Norwegian coastal areas, the copepod Calanus finmarchicus. Copepods were subjected to two 96-hr tests: (1) acute toxicity test where mortality was determined and (2) treated copepods were exposed to concentrations below the No Observed Effect Concentration (0.75 mg/L) H 2 O 2 and analyzed for antioxidant enzyme activities, as well as levels of glutathione (GSH) and malondialdehyde (MDA). Compared to available and comparable LC 50 values from the literature, our results suggest that C. finmarchicus is highly sensitive to H 2 O 2 . However, 96-hr exposure of C. finmarchicus to 0.75 mg H 2 O 2 /L did not significantly affect the antioxidant systems even though the concentration is just below the level where mortality is expected. Data suggest that aqueous H 2 O 2 exposure did not cause cellular accumulation with associated oxidative stress, but rather produced acute effects on copepod surface (carapace). Further investigation is required to ensure that aqueous exposure during H 2 O 2 treatment in salmon fish farms does not exert adverse effects on local non-target crustacean species and populations. In particular, studies on copepod developmental stages with a more permeable carapace are warranted.

Modeling the acute health effects of astronauts from exposure to large solar particle events.

PubMed

Hu, Shaowen; Kim, Myung-Hee Y; McClellan, Gene E; Cucinotta, Francis A

2009-04-01

Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed.

Acute, but not Chronic, Exposure to Arsenic Provokes Glucose Intolerance in Rats: Possible Roles for Oxidative Stress and the Adrenergic Pathway.

PubMed

Rezaei, Mohsen; Khodayar, Mohammd Javad; Seydi, Enayatollah; Soheila, Alboghobeish; Parsi, Isa Kazemzadeh

2017-06-01

Health problems due to heavy metals have become a worldwide concern. Along with its carcinogenicity, arsenic exposure results in impairment of glucose metabolism and insulin secretion as well as altered gene expression and signal transduction. However, the exact mechanism behind the behaviour of arsenic on glucose homeostasis and insulin secretion has not yet been fully understood. Fasting blood sugar and glucose tolerance tests were evaluated. In this study, we demonstrated that arsenic, when acutely administered, induced glucose intolerance in rats, although its chronic oral exposure did not provoke any glucose intolerance or hyperglycemia in rats. The protective activity of N-acetylcysteine, carvedilol and propranolol in male rats exposed to arsenic were also assessed, and N-acetylcysteine, particularly at 40 and 80 mg/kg, prevented the glucose intolerance induced in rats by arsenic. The present study showed that acute, but not chronic, contact with arsenic generates significant changes in the normal glucose tolerance pattern that may be due fundamentally to overproduction of reactive oxygen species and oxidative stress and is preventable by using N-acetylcysteine, a thiol-containing antioxidant. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

Pregnancy outcomes after paternal radiofrequency field exposure aboard fast patrol boats.

PubMed

Baste, Valborg; Moen, Bente E; Oftedal, Gunnhild; Strand, Leif Age; Bjørge, Line; Mild, Kjell Hansson

2012-04-01

To investigate adverse reproductive outcomes among male employees in the Royal Norwegian Navy exposed to radiofrequency electromagnetic fields aboard fast patrol boats. Cohort study of Royal Norwegian Navy servicemen linked to the Medical Birth Registry of Norway, including singleton offspring born between 1967 and 2008 (n = 37,920). Exposure during the last 3 months before conception (acute) and exposure more than 3 months before conception (nonacute) were analyzed. Perinatal mortality and preeclampsia increased after service aboard fast patrol boats during an acute period and also after increased estimated radiofrequency exposure during an acute period, compared with service aboard other vessels. No associations were found between nonacute exposure and any of the reproductive outcomes. Paternal work aboard fast patrol boats during an acute period was associated with perinatal mortality and preeclampsia, but the cause is not clear.

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

PubMed

Srivastava, Ritesh K; Traylor, Amie M; Li, Changzhao; Feng, Wenguang; Guo, Lingling; Antony, Veena B; Schoeb, Trenton R; Agarwal, Anupam; Athar, Mohammad

2018-06-01

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-H 2 A.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 BCL 2 . 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.

Stress response in rat brain after different durations of noise exposure.

PubMed

Samson, James; Sheeladevi, Rathinasamy; Ravindran, Rajan; Senthilvelan, Manohar

2007-01-01

The alteration in the levels of plasma corticosterone, brain norepinephrine (NE), and expression of brain heat shock proteins (Hsp70) after different durations of noise exposure (acute, 1 day; sub-acute, 15 days; chronic, 30 days) has been studied to analyze their role in combating time-dependent stress effects of noise. Broadband white noise (100dB) exposure to male Wistar albino rats significantly increased the levels of plasma corticosterone and NE in all three durations of noise exposure. The sustained increase observed in their levels in the chronic group suggests that animals are not getting adapted to noise even after 30 days of exposure. The important role of Hsp70 in combating noise induced stress is evident from the significant increase in its expression after chronic exposure, while there was a reciprocal decrease in the NE and corticosterone when compared with their levels after acute and sub-acute noise exposure. This clearly indicates that the time-dependent stress response to noise exposure is a complex mechanism involving highly interconnected systems such as hypothalamo-pituitary-adrenal (HPA) axis, heat shock proteins and may have serious implications in vital organs, particularly in the brain when there is a prolonged noise exposure.

Pre- and Postnatal Parental Smoking and Acute Otitis Media in Early Childhood

PubMed Central

Håberg, Siri E.; Bentdal, Yngvild E.; London, Stephanie J.; Kværner, Kari J.; Nystad, Wenche; Nafstad, Per

2010-01-01

Aim To explore associations between acute otitis media in early childhood and prenatal and postnatal tobacco smoke exposure. Methods Subjects were 32,077 children born 2000 – 2005 in the Norwegian Mother and Child Study with questionnaire data on tobacco smoke exposure and acute otitis media up to 18 months of age. Multivariate regression models were used to obtain adjusted relative risks for acute otitis media. Results Acute otitis media was slightly more common in children exposed to parental smoking. The incidence from 0–6 months was 4.7% in unexposed children, and 6.0% in children exposed both pre-and postnatally. After adjusting for postnatal exposure and covariates, the relative risk for acute otitis media 0–6 months when exposed to maternal smoking in pregnancy was 1.34, 95% confidence interval: 1.06–1.69. Maternal smoking in pregnancy was associated with acute otitis media up to 12 months of age. Compared to non-exposed children, there was a slightly increased risk of recurrent acute otitis media for children exposed both pre- and postnatally with a relative risk of 1.24, 95% confidence interval: 1.01–1.52,. Conclusion Even in a cohort with relatively low exposure levels of parental smoking, maternal smoking in pregnancy was associated with an increased risk of acute otitis media in early childhood. PMID:19764924

Parental Exposure to Workplace Carcinogens and the Risk of Development of Acute Leukemia in Infants. Case-Control Study.

PubMed

Pérez-Saldivar, María Luisa; Fajardo-Gutiérrez, Arturo; Sierra-Ramírez, José Alfredo; Núñez-Villegas, Nancy; Pérez-Lorenzana, Héctor; Dorantes-Acosta, Elisa María; Román-Zepeda, Pedro Francisco; Rodríguez-Zepeda, María Del Carmen; González-Ulivarri, Juana Esther; López-Santiago, Norma; Martínez-Silva, Sofía Irene; Paredes-Aguilera, Rogelio; Velázquez-Aviña, Martha Margarita; Flores-Lujano, Janet; Jiménez-Hernández, Elva; Núñez-Enríquez, Juan Carlos; Bekker-Méndez, Vilma Carolina; Mejía-Aranguré, Juan Manuel

2016-11-01

Occupational exposure of parents to carcinogens is of great interest in the etiology of leukemias. Evidence of the impact of such exposure on infants or small children is scarce. Here we estimated whether occupational exposure of parents to carcinogens could be a risk factor for leukemias in their children. Cases of acute leukemia (AL) in infants ≤24 months old diagnosed in Mexico City (1998-2013) were included in a population-based, case-control study. Each of the 195 cases was matched with at least one healthy child (n = 369). For each of four exposure windows studied, the degree of exposure to carcinogens was determined for both parents by using a validated occupational exposure index. An unconditional logistic regression was carried out. Odds ratios (OR) and the 95% confidence intervals (CI) of the overall occupational exposure for parents during the four exposure windows indicated no association with risk of AL in their children. Pre-conception, the OR by the father 0.77 (0.49-1.21), by the mother 1.03 (0.50-2.11); during pregnancy, father 0.66 (0.38-1.15), mother 1.79 (0.46-6.90); during breastfeeding, father 0.75 (0.43-1.30), mother 0.96 (0.21-4.30); and after birth, father 0.74 (0.45-1.22), mother 0.90 (0.24-3.32). The statistical power of the sample size to identify an OR ≥2 and an exposure of ≥10% among controls was 78%. These data support the idea that parents' occupational exposure during any of the periods studied was not a risk factor contributing to the etiology of AL in infants ≤24 months of age. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

Utilizing Telehealth to Support Treatment of Acute Stress Disorder in a Theater of War: Prolonged Exposure via Clinical Videoconferencing.

PubMed

Pelton, Dan; Wangelin, Bethany; Tuerk, Peter

2015-05-01

Posttraumatic stress disorder (PTSD) and acute stress disorder are prevalent mental health diagnoses associated with the military operations in Iraq and Afghanistan and are especially significant in service members returning from combat. Prolonged exposure (PE) therapy is a highly effective behavioral treatment for these symptoms, and providing this treatment as soon as possible, even in the midst of a soldier's combat deployment, has strong potential benefits. In the current case study, telehealth technology was used to support the delivery of PE therapy to treat a service member diagnosed with acute stress disorder in a war zone. PE was conducted face-to-face on the relatively secure Forward Operating Base for the first half of therapy and via clinical videoconferencing (CV) to the service member's remote combat outpost during the later stages of therapy. The service member exhibited marked improvements in symptoms over 10 sessions. Results are consistent with previous empirical findings and highlight the potential benefits of using telehealth to deliver evidenced-based treatment for traumatic stress disorders in a war zone. This case study provides a preliminary working model for delivering PE in a combat environment using multiple delivery systems. Benefits and clinical utility of CV-delivered exposure therapy are discussed, particularly for providers pending future operational deployments (e.g., including members of the military, independent government agencies, and first responders) and for those treating patients in remote locations.

Quantitative structure-activity relationship modeling of rat acute toxicity by oral exposure.

PubMed

Zhu, Hao; Martin, Todd M; Ye, Lin; Sedykh, Alexander; Young, Douglas M; Tropsha, Alexander

2009-12-01

Few quantitative structure-activity relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity end points. In this study, a comprehensive data set of 7385 compounds with their most conservative lethal dose (LD(50)) values has been compiled. A combinatorial QSAR approach has been employed to develop robust and predictive models of acute toxicity in rats caused by oral exposure to chemicals. To enable fair comparison between the predictive power of models generated in this study versus a commercial toxicity predictor, TOPKAT (Toxicity Prediction by Komputer Assisted Technology), a modeling subset of the entire data set was selected that included all 3472 compounds used in TOPKAT's training set. The remaining 3913 compounds, which were not present in the TOPKAT training set, were used as the external validation set. QSAR models of five different types were developed for the modeling set. The prediction accuracy for the external validation set was estimated by determination coefficient R(2) of linear regression between actual and predicted LD(50) values. The use of the applicability domain threshold implemented in most models generally improved the external prediction accuracy but expectedly led to the decrease in chemical space coverage; depending on the applicability domain threshold, R(2) ranged from 0.24 to 0.70. Ultimately, several consensus models were developed by averaging the predicted LD(50) for every compound using all five models. The consensus models afforded higher prediction accuracy for the external validation data set with the higher coverage as compared to individual constituent models. The validated consensus LD(50) models developed in this study can be used as reliable computational predictors of in vivo acute toxicity.

An outbreak of acute delirium from exposure to the synthetic cannabinoid AB-CHMINACA.

PubMed

Tyndall, Joseph A; Gerona, Roy; De Portu, Giuliano; Trecki, Jordan; Elie, Marie-Carmelle; Lucas, Judith; Slish, John; Rand, Kenneth; Bazydlo, Lindsay; Holder, Martina; Ryan, Matthew F; Myers, Paul; Iovine, Nicole; Plourde, Michelle; Weeks, Emily; Hanley, James R; Endres, Greg; St Germaine, Danielle; Dobrowolski, Paul J; Schwartz, Michael

2015-01-01

Synthetic cannabinoid containing products are a public health threat as reflected by a number of outbreaks of serious adverse health effects over the past 4 years. The designer drug epidemic is characterized by the rapid turnover of synthetic cannabinoid compounds on the market which creates a challenge in identifying the particular etiology of an outbreak, confirming exposure in cases, and providing current information to law enforcement. Between 28 May 2014 and 8 June 2014, 35 patients were evaluated and treated at the University of Florida Health Medical Center in Gainesville following reported exposure to a synthetic cannabinoid containing product obtained from a common source. Patients demonstrated acute delirium (24) and seizures (14), and five required ventilator support and ICU-level care; none died. The presence of N-[(1S)-1-(aminocarbonyl)-2-methylpropyl]-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (AB-CHMINACA), or one of its predicted metabolites was confirmed in 15 of 21 cases. A rapid public health response and aggressive public messaging prevented further morbidity, identified the source, and led to law enforcement seizure of the implicated product. The significance of this outbreak lies as much in the rapid occurrence of unpredictable, life-threatening adverse health effects from a newly identified synthetic cannabinoid compound as it does in the multidisciplinary investigation and novel partnership between local public health, the laboratory, and the chemical industry, resulting in termination of the outbreak. A coordinated response and collaboration between law enforcement, the local public health, emergency medical services and Health Center staff, were all key interventions in preventing a more substantial public health outbreak resulting from use of a novel synthetic cannabinoid compound. Real time collaborations between toxicology laboratories, suppliers of analytical standards and the public health system may be useful in the face of

Acute lung injury following inhalation exposure to nerve agent VX in guinea pigs.

PubMed

Wright, Benjamin S; Rezk, Peter E; Graham, Jacob R; Steele, Keith E; Gordon, Richard K; Sciuto, Alfred M; Nambiar, Madhusoodana P

2006-05-01

A microinstillation technique of inhalation exposure was utilized to assess lung injury following chemical warfare nerve agent VX [methylphosphonothioic acid S-(2-[bis(1-methylethyl)amino]ethyl) O-ethyl ester] exposure in guinea pigs. Animals were anesthetized using Telazol-meditomidine, gently intubated, and VX was aerosolized using a microcatheter placed 2 cm above the bifurcation of the trachea. Different doses (50.4 microg/m3, 70.4 micro g/m(m3), 90.4 microg/m(m3)) of VX were administered at 40 pulses/min for 5 min. Dosing of VX was calculated by the volume of aerosol produced per 200 pulses and diluting the agent accordingly. Although the survival rate of animals exposed to different doses of VX was similar to the controls, nearly a 20% weight reduction was observed in exposed animals. After 24 h of recovery, the animals were euthanized and bronchoalveolar lavage (BAL) was performed with oxygen free saline. BAL was centrifuged and separated into BAL fluid (BALF) and BAL cells (BALC) and analyzed for indication of lung injury. The edema by dry/wet weight ratio of the accessory lobe increased 11% in VX-treated animals. BAL cell number was increased in VX-treated animals compared to controls, independent of dosage. Trypan blue viability assay indicated an increase in BAL cell death in 70.4 microg/m(m3) and 90.4 microg/m(m3) VX-exposed animals. Differential cell counting of BALC indicated a decrease in macrophage/monocytes in VX-exposed animals. The total amount of BAL protein increased gradually with the exposed dose of VX and was highest in animals exposed to 90.4 microg/m(m3), indicating that this dose of VX caused lung injury that persisted at 24 h. In addition, histopathology results also suggest that inhalation exposure to VX induces acute lung injury.

Effects of acute tryptophan depletion on affective processing in first-degree relatives of depressive patients and controls after exposure to uncontrollable stress.

PubMed

Firk, Christine; Markus, C Rob

2008-08-01

Individuals with a family history of depression may be more likely to develop depression due to an innate vulnerability of their serotonergic system. However, even though serotonergic vulnerability may constitute a risk factor in the development of depression, it does not seem to be sufficient to cause a depressive episode. Based on previous data, it is suggested that stress may be a mediating factor. This study examined the role of serotonin (5-HT) in stress coping in individuals with or without a family history of depression. Nineteen healthy first-degree relatives of depressive patients (FH+) and 19 healthy controls without a family history of depression (FH-) were tested in a double-blind placebo-controlled design for affective processing under acute stress exposure, following acute tryptophan depletion (ATD) or placebo. Significant negative effects were found of stress on affective processing in FH- and FH+. In addition, FH- responded slower to positive words after stress only following ATD, whereas FH+ responded marginally slower under stress already after placebo and before stress following ATD. Acute stress exposure reduces positive affective bias; supporting the role of stress as an important predecessor in the development of depression. Furthermore, FH+ may be more susceptible than FH- to the negative effects of stress as well as to the negative effects of ATD. The results support the assumption that the 5-HT system is involved in stress resilience and may be more vulnerable in first-degree relatives of depression.

IL-6, a central acute-phase mediator, as an early biomarker for exposure to zinc-based metal fumes.

PubMed

Baumann, R; Joraslafsky, S; Markert, A; Rack, I; Davatgarbenam, S; Kossack, V; Gerhards, B; Kraus, T; Brand, P; Gube, M

2016-12-12

-γ), cell counts] and the lung function parameters did not show any significant changes after exposure. Consistent with its role of the mediation of the acute-phase response, systemic increases of IL-6 after welding fume exposure peak at 10h before the increases of the acute-phase reactants CRP and SAA at 29h. IL-6 may represent a highly sensitive and early biomarker for the exposure to metal fumes containing zinc and copper. As IL-6, CRP and SAA are independent, strong risk markers for future cardiovascular diseases, these data may particularly be important for long-term welders with respect to their cardiovascular health. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mild MPP+ exposure impairs autophagic degradation through a novel lysosomal acidity-independent mechanism.

PubMed

Miyara, Masatsugu; Kotake, Yaichiro; Tokunaga, Wataru; Sanoh, Seigo; Ohta, Shigeru

2016-10-01

Parkinson's disease (PD) is the second most common neurodegenerative disorder, but its underlying cause remains unknown. Although recent studies using PD-related neurotoxin MPP + suggest autophagy involvement in the pathogenesis of PD, the effect of MPP + on autophagic processes under mild exposure, which mimics the slow progressive nature of PD, remains largely unclear. We examined the effect of mild MPP + exposure (10 and 200 μM for 48 h), which induces a more slowly developing cell death, on autophagic processes and the mechanistic differences with acute MPP + toxicity (2.5 and 5 mM for 24 h). In SH-SY5Y cells, mild MPP + exposure predominantly inhibited autophagosome degradation, whereas acute MPP + exposure inhibited both autophagosome degradation and basal autophagy. Mild MPP + exposure reduced lysosomal hydrolase cathepsin D activity without changing lysosomal acidity, whereas acute exposure decreased lysosomal density. Lysosome biogenesis enhancers trehalose and rapamycin partially alleviated mild MPP + exposure induced impaired autophagosome degradation and cell death, but did not prevent the pathogenic response to acute MPP + exposure, suggesting irreversible lysosomal damage. We demonstrated impaired autophagic degradation by MPP + exposure and mechanistic differences between mild and acute MPP + toxicities. Mild MPP + toxicity impaired autophagosome degradation through novel lysosomal acidity-independent mechanisms. Sustained mild lysosomal damage may contribute to PD. We examined the effects of MPP + on autophagic processes under mild exposure, which mimics the slow progressive nature of Parkinson's disease, in SH-SY5Y cells. This study demonstrated impaired autophagic degradation through a reduction in lysosomal cathepsin D activity without altering lysosomal acidity by mild MPP + exposure. Mechanistic differences between acute and mild MPP + toxicity were also observed. Sustained mild damage of lysosome may be an underlying cause of Parkinson