WorldWideScience

Sample records for chronic passive exposure

  1. Active and Passive Smoking, Chronic Disease and Poverty in China ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Active and Passive Smoking, Chronic Disease and Poverty in China. The globalization ... The impending burden of tobacco-related chronic disease will be significant in a population of 1.3 billion. ... Center for Health Statistics and Information.

  2. The chronic exposure case

    International Nuclear Information System (INIS)

    Barescut, Jean-Claude

    2006-01-01

    will not have the same effect if it is added to one set of cofactors or to another one. This is critical in order to perform a global risk management. There are some signs that the management of radioactive risk is at a turn today. ICRP is about to issue new recommendations and wishes to include biota protection. Some dissident scientists are emitting reserves concerning risk evaluation and lastly, the non nuclear world is rapidly evolving toward a more cautious control (REACH European directive) of chemicals suspected to impact man or environmental health. The paper has the following contents: Some technical points to address; Chronic versus acute exposure; Long versus short life radionuclides; Homogeneity versus inhomogeneity; Combined stresses; How to tackle the problem; What extent of the dose concept; Contribution of epidemiology; Contribution of molecular and fundamental biology of low level systems; Ecological point a view; In situ and laboratory radioecology; IRSN researches; A few deviations to linearity; A real population effect; Effect of 241 Am on daphnia magna. The examples given above are only a part of researches currently done at the IRSN. Many other researches, either in ENVIRHOM or closely related fields, are ongoing: performance of central nervous system, intestinal transfer, experiments on soil aging, in situ experiments on Chernobyl contaminated soils, experiments with other radionuclides (Se, Tc, Co, etc). This review is based upon the ENVIRHOM research program supported by the Institute for Radioprotection and Nuclear Safety

  3. Evaluation of exposure to carbon monoxide associated with passive smoking

    International Nuclear Information System (INIS)

    Jo, W.-K.; Oh, J.-W.; Dong, J.-I.

    2004-01-01

    The current study measured breath carbon monoxide (CO) concentrations prior to and at prescribed time intervals after exposure to passive smoking under controlled conditions, along with the air CO concentration in the exposure room during the exposure periods. The postexposure breath CO levels were 1.4-2.7 times higher than the background breath CO levels after 30 min of exposure, yet only slightly higher after 10 min of exposure, thereby confirming that exposure to CO from passive smoking causes a significant body burden of CO. The air CO concentration gradually increased during the burning of a cigarette(s), regardless of the exposure duration, whereas it slightly decreased after burning. However, the pattern of breath CO decay was similar for the two different types of exposure (during and after a cigarette(s)) in each subject. The decrease in the postexposure alveolar CO concentrations was slow even in the early phase of the decay curves, indicating a monocompartment uptake and elimination model for the human body. The half-lives (78-277 min) estimated in the present study were comparable to those reported in previous studies associated with CO exposure from active smoking or other activities. The current study also evaluated the CO exposure of visitors and workers at three different types of recreation facility (bars, Internet cafes, and billiard halls) typically associated with passive smoking. The results confirmed that passive smoking is the major contributor to the CO exposure of nonsmoking visitors in a recreation environment. In addition, workplace exposure to CO from passive smoking was found to be the most important contributor to the daily CO exposure of nonsmoking recreation workers

  4. Passive exposure to nicotine from e-cigarettes.

    Science.gov (United States)

    Gallart-Mateu, D; Elbal, L; Armenta, S; de la Guardia, M

    2016-05-15

    A procedure based on the use of ion mobility spectrometry (IMS), after liquid-liquid microextraction (LLME), has been successfully employed for the determination of passive exposure to nicotine from cigarette and e-cigarette smoking. Nicotine has been determined in exhaled breath and oral fluids of both, active and passive smokers. The aforementioned studies, made in closed environments, evidenced that the exhaled breath after conventional blend cigarette smoke provides nicotine levels of the order of 220 ng per puff, in the case of experienced smokers, being exhaled only 32 ng in the case of e-cigarettes. On the other hand, the nicotine amount in oral fluids of passive vapers was between 8 and 14 µg L(-1) lower than the average value of 38±14 µg L(-1) found for passive smokers of rolling tobacco and clearly lower than the 79±36 µg L(-1) obtained from passive smokers of classical yellow blend. This study was also placed in the frame of the verification of the e-cigarettes composition. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Chronic toxicity of selected polycyclic aromatic hydrocarbons to algae and crustaceans using passive dosing.

    Science.gov (United States)

    Bragin, Gail E; Parkerton, Thomas F; Redman, Aaron D; Letinksi, Daniel J; Butler, Josh D; Paumen, Miriam Leon; Sutherland, Cary A; Knarr, Tricia M; Comber, Mike; den Haan, Klaas

    2016-12-01

    Because of the large number of possible aromatic hydrocarbon structures, predictive toxicity models are needed to support substance hazard and risk assessments. Calibration and evaluation of such models requires toxicity data with well-defined exposures. The present study has applied a passive dosing method to generate reliable chronic effects data for 8 polycyclic aromatic hydrocarbons (PAHs) on the green algae Pseudokirchneriella subcapitata and the crustacean Ceriodaphnia dubia. The observed toxicity of these substances on algal growth rate and neonate production were then compared with available literature toxicity data for these species, as well as target lipid model and chemical activity-based model predictions. The use of passive dosing provided well-controlled exposures that yielded more consistent data sets than attained by past literature studies. Results from the present study, which were designed to exclude the complicating influence of ultraviolet light, were found to be well described by both target lipid model and chemical activity effect models. The present study also found that the lack of chronic effects for high molecular weight PAHs was consistent with the limited chemical activity that could be achieved for these compounds in the aqueous test media. Findings from this analysis highlight that variability in past literature toxicity data for PAHs may be complicated by both poorly controlled exposures and photochemical processes that can modulate both exposure and toxicity. Environ Toxicol Chem 2016;35:2948-2957. © 2016 SETAC. © 2016 SETAC.

  6. Occupational Exposures and Chronic Airflow Limitation

    Directory of Open Access Journals (Sweden)

    Helen Dimich-Ward

    1996-01-01

    Full Text Available The recent literature was reviewed to evaluate whether chronic airflow limitation is associated with occupational exposures to dusts. Only those studies that controlled for the effects of smoking were included. There is compelling evidence that exposure to inorganic dusts, such as from coal and hardrock mining or asbestos, are associated with the development of chronic airflow limitation, independently of pneumoconiosis. Nonsmoking gold miners are particularly at high risk of airflow obstruction and emphysema. Findings from studies of organic dusts, such as exposures to wood, cotton, grain or other agricultural dusts, or to mixed dust exposures, were less consistent but tended to show positive dose-response associations. In the majority of studies, no statistical interaction was shown between dust exposures and smoking; however, the effects of the dust exposures were often more pronounced. An occupational history should be considered, in addition to a smoking history, as an integral part of an investigation of chronic airflow limitation in a patient.

  7. Anhedonia but not passive floating is an indicator of depressive-like behavior in two chronic stress paradigms.

    Science.gov (United States)

    Stepanichev, Mikhail Yu; Tishkina, Anna O; Novikova, Margarita R; Levshina, Irina P; Freiman, Sofiya V; Onufriev, Mikhail V; Levchenko, Olga A; Lazareva, Natalia A; Gulyaeva, Natalia V

    2016-01-01

    Depression is the most common form of mental disability in the world. Depressive episodes may be precipitated by severe acute stressful events or by mild chronic stressors. Studies on the mechanisms of depression require both appropriate experimental models (most of them based on the exposure of animals to chronic stressors), and appropriate tests for assessment of depressive states. In this study male Wistar rats were exposed to two different chronic stress paradigms: an eight-week chronic unpredictable mild stress or a two-week combined chronic stress. The behavioral effects of stress were evaluated using sucrose preference, forced swim and open field tests. After the exposure to chronic unpredictable mild stress, anhedonia was developed, activity in the open field increased, while no changes in the duration of passive floating could be detected. After chronic combined stress, anhedonia was also evident, whereas behavior in the open field and forced swim test did not change. The levels of corticosterone in the blood and brain structures involved in stress-response did not differ from control in both experiments. The absence of significant changes in corticosterone levels and passive floating may be indicative of the adaptation of animals to chronic stress. Anhedonia appears to be a more sensitive indicator of depressive-like behavioral effects of chronic stress as compared to behavior in the forced swim or open field tests.

  8. Passive Heat Exposure Alters Perception and Executive Function

    Directory of Open Access Journals (Sweden)

    Rachel A. Malcolm

    2018-05-01

    Full Text Available Findings regarding the influence of passive heat exposure on cognitive function remain equivocal due to a number of methodological issues including variation in the domains of cognition examined. In a randomized crossover design, forty-one male participants completed a battery of cognitive function tests [Visual Search, Stroop, Corsi Blocks and Rapid Visual Information Processing (RVIP tests] prior to and following 1 h of passive rest in either hot (39.6 ± 0.4°C, 50.8 ± 2.3% Rh or moderate (21.2 ± 1.8°C, 41.9 ± 11.4% Rh conditions. Subjective feelings of heat exposure, arousal and feeling were assessed alongside physiological measures including core temperature, skin temperature and heart rate, at baseline and throughout the protocol. Response times were slower in the hot trial on the simple (main effect of trial, P < 0.001 and complex (main effect of trial, P < 0.001 levels of the Stroop test (Hot: 872 ± 198 ms; Moderate: 834 ± 177 ms and the simple level of the visual search test (Hot: 354 ± 54 ms; Moderate: 331 ± 47 ms (main effect of trial, P < 0.001. Participants demonstrated superior accuracy on the simple level of the Visual Search test in the hot trial (Hot: 98.5 ± 3.1%; Moderate: 97.4 ± 3.6% (main effect of trial, P = 0.035. Participants also demonstrated an improvement in accuracy on the complex level of the visual search test following 1 h passive heat exposure (Pre: 96.8 ± 5.9%; Post: 98.1 ± 3.1%, whilst a decrement was seen across the trial in the moderate condition (Pre: 97.7 ± 3.5; Post: 97.0 ± 5.1% (time*trial interaction, P = 0.029. No differences in performance were observed on the RVIP or Corsi Blocks tests (all P > 0.05. Subjective feelings of thermal sensation and felt arousal were higher, feeling was lower in the hot trial, whilst skin temperature, core temperature and heart rate were higher (main effects of trial, all P < 0.001. The findings of the present study suggest that response times for perception

  9. Lung functions at school age and chronic exposure to outdoor and indoor air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Neuberger, M; Kundi, M; Wiesenberger, W [Vienna Univ. (Austria). Dept. of Preventive Medicine

    1996-12-31

    Early signs of lung function impairment have been found correlated with annual concentrations of outdoor air pollutants and with passive smoking. To investigate the combined effects of both indicators of chronic exposure to air pollution pulmonary functions in all elementary and high school children of an Austrian town was examined for 5 years. (author)

  10. Lung functions at school age and chronic exposure to outdoor and indoor air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Neuberger, M.; Kundi, M.; Wiesenberger, W. [Vienna Univ. (Austria). Dept. of Preventive Medicine

    1995-12-31

    Early signs of lung function impairment have been found correlated with annual concentrations of outdoor air pollutants and with passive smoking. To investigate the combined effects of both indicators of chronic exposure to air pollution pulmonary functions in all elementary and high school children of an Austrian town was examined for 5 years. (author)

  11. Health Effects of Chronic Arsenic Exposure

    Directory of Open Access Journals (Sweden)

    Young-Seoub Hong

    2014-09-01

    Full Text Available Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.

  12. Brick mortar exposure and chronic lymphocytic leukemia.

    Science.gov (United States)

    Markovic-Denic, L; Jankovic, S; Marinkovic, J; Radovanovic, Z

    1995-01-01

    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL.

  13. Brick mortar exposure and chronic lymphocytic leukemia

    International Nuclear Information System (INIS)

    Markovic-Denic, Lj.; Jankovic, S.; Marinkovic, J.; Radovanovic, Z.

    1995-01-01

    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author)

  14. Brick mortar exposure and chronic lymphocytic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Markovic-Denic, Lj; Jankovic, S [Institute of Epidemiology, Faculty of Medicine, Belgrade (Yugoslavia); Marinkovic, J [Institute of Social Medicine, Statistics and Healt Research, Faculty of Medicine, Belgrade (Yugoslavia); Radovanovic, Z [Department of Community Medicine and Behavioural Sciences, Faculty of Medicine, 13110 Safat (Kuwait)

    1996-12-31

    A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence, (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL. (author) 1 tab., 30 refs.

  15. [Interventions on the exposure of non-smoking pregnant women to passive smoking].

    Science.gov (United States)

    Yao, Ting-ting; Chen, Xue-yun; Hu, De-wei; Mao, Zheng-zhong

    2008-09-01

    To investigate the extent of exposure of non-smoking pregnant women to passive smoking; to undertake interventions on the knowledge, attitudes and behaviors of those women toward passive smoking; and to evaluate the effectiveness of the interventions. A total of 128 non-smoking pregnant women participated in the survey. Their knowledge, attitudes and behaviors towards passive smoking were measured by a self-administered questionnaire. A sixteen-week intervention was undertaken. The knowledge and attitudes of the non-smoking pregnant women towards passive smoking improved significantly, as well as their attempts to avoid exposure to the passive smoking brought by their smoking husbands or other family members. Telephone counseling, booklets and doctors' advices were the most acceptable approaches of health education. The comprehensive interventions are effective for improving the knowledge, attitudes and behaviors of non-smoking women toward passive smoking.

  16. Active and realistic passive marijuana exposure tested by three immunoassays and GC/MS in urine

    Energy Technology Data Exchange (ETDEWEB)

    Mule, S.J.; Lomax, P.; Gross, S.J.

    1988-05-01

    Human urine samples obtained before and after active and passive exposure to marijuana were analyzed by immune kits (Roche, Amersham, and Syva) and gas chromatography/mass spectrometry (GC/MS). Seven of eight subjects were positive for the entire five-day test period with one immune kit. The latter correlated with GC/MS in 98% of the samples. Passive inhalation experiments under conditions likely to reflect realistic exposure resulted consistently in less than 10 ng/mL of cannabinoids. The 10-100-ng/mL cannabinoid concentration range essential for detection of occasional and moderate marijuana users is thus unaffected by realistic passive inhalation.

  17. Active and realistic passive marijuana exposure tested by three immunoassays and GC/MS in urine

    International Nuclear Information System (INIS)

    Mule, S.J.; Lomax, P.; Gross, S.J.

    1988-01-01

    Human urine samples obtained before and after active and passive exposure to marijuana were analyzed by immune kits (Roche, Amersham, and Syva) and gas chromatography/mass spectrometry (GC/MS). Seven of eight subjects were positive for the entire five-day test period with one immune kit. The latter correlated with GC/MS in 98% of the samples. Passive inhalation experiments under conditions likely to reflect realistic exposure resulted consistently in less than 10 ng/mL of cannabinoids. The 10-100-ng/mL cannabinoid concentration range essential for detection of occasional and moderate marijuana users is thus unaffected by realistic passive inhalation

  18. Measurement of passive ankle stiffness in subjects with chronic hemiparesis using a novel ankle robot

    Science.gov (United States)

    Roy, Anindo; Bever, Christopher T.; Forrester, Larry W.; Macko, Richard F.; Hogan, Neville

    2011-01-01

    Our objective in this study was to assess passive mechanical stiffness in the ankle of chronic hemiparetic stroke survivors and to compare it with those of healthy young and older (age-matched) individuals. Given the importance of the ankle during locomotion, an accurate estimate of passive ankle stiffness would be valuable for locomotor rehabilitation, potentially providing a measure of recovery and a quantitative basis to design treatment protocols. Using a novel ankle robot, we characterized passive ankle stiffness both in sagittal and in frontal planes by applying perturbations to the ankle joint over the entire range of motion with subjects in a relaxed state. We found that passive stiffness of the affected ankle joint was significantly higher in chronic stroke survivors than in healthy adults of a similar cohort, both in the sagittal as well as frontal plane of movement, in three out of four directions tested with indistinguishable stiffness values in plantarflexion direction. Our findings are comparable to the literature, thus indicating its plausibility, and, to our knowledge, report for the first time passive stiffness in the frontal plane for persons with chronic stroke and older healthy adults. PMID:21346215

  19. Cannabinoids in oral fluid following passive exposure to marijuana smoke

    NARCIS (Netherlands)

    Moore, Christine; Coulter, Cynthia; Uges, Donald; Tuyay, James; van der Linde, Susanne; van Leeuwen, Arthur; Garnier, Margaux; Orbita, Jonathan

    2011-01-01

    The concentration of tetrahydrocannabinol (THC) and its main metabolite 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) as well as cannabinol (CBN), and cannabidiol (CBD) were measured in oral fluid following realistic exposure to marijuana in a Dutch coffee-shop. Ten healthy

  20. Exposure to passive smoking and rheumatoid arthritis risk: results from the Swedish EIRA study.

    Science.gov (United States)

    Hedström, Anna Karin; Klareskog, Lars; Alfredsson, Lars

    2018-07-01

    Smoking has consistently been associated with increased risk of developing rheumatoid arthritis (RA). The aim of this study was to estimate the influence of passive smoking on the risk of developing anti-cyclic citrullinated peptide antibodies (ACPA)-positive and ACPA-negative RA. A population-based case-control study using incident cases of RA was performed in Sweden, and the study population in this report was restricted to include never-smokers (589 cases, 1764 controls). The incidence of RA among never-smokers who had been exposed to passive smoking was compared with that of never-smokers who had never been exposed, by calculating the OR with a 95% CI employing logistic regression. No association was observed between exposure to passive smoking and RA risk (OR 1.0, 95% CI 0.8 to 1.2 for ACPA-positive RA, and OR 0.9, 95% CI 0.7 to 1.2, for ACPA-negative RA). No suggestion of a trend between duration of passive smoking and RA risk was observed. No association was observed between exposure to passive smoking and RA risk, which may be explained by a threshold below which no association between smoke exposure and RA occurs. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

    International Nuclear Information System (INIS)

    Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang; Huang, Changjiang; Yang, Dongren

    2016-01-01

    Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

  2. Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Huang, Changjiang, E-mail: cjhuang5711@163.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Yang, Dongren, E-mail: yangdongren@yahoo.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China)

    2016-07-15

    Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

  3. Passive monitoring techniques for evaluating atmospheric ozone and nitrogen exposure and deposition to California ecosystems

    Science.gov (United States)

    Mark E. Fenn; Andrzej Bytnerowicz; Susan L. Schilling

    2018-01-01

    Measuring the exposure of ecosystems to ecologically relevant pollutants is needed for evaluating ecosystem effects and to identify regions and resources at risk. In California, ozone (O3) and nitrogen (N) pollutants are of greatest concern for ecological effects. "Passive" monitoring methods have been developed to obtain spatially...

  4. Passive cannabis smoke exposure and oral fluid testing. II. Two studies of extreme cannabis smoke exposure in a motor vehicle.

    Science.gov (United States)

    Niedbala, R Sam; Kardos, Keith W; Fritch, Dean F; Kunsman, Kenneth P; Blum, Kristen A; Newland, Gregory A; Waga, Joe; Kurtz, Lisa; Bronsgeest, Matth; Cone, Edward J

    2005-10-01

    Two studies were conducted to determine if extreme passive exposure to cannabis smoke in a motor vehicle would produce positive results for delta-tetrahydrocannabinol (THC) in oral fluid. Passive exposure to cannabis smoke in an unventilated room has been shown to produce a transient appearance of THC in oral fluid for up to 30 min. However, it is well known that such factors as room size and extent of smoke exposure can affect results. Questions have also been raised concerning the effects of tobacco when mixed with marijuana and THC content. We conducted two passive cannabis studies under severe passive smoke exposure conditions in an unventilated eight-passenger van. Four passive subjects sat alongside four active cannabis smokers who each smoked a single cannabis cigarette containing either 5.4%, 39.5 mg THC (Study 1) or 10.4%, 83.2 mg THC (Study 2). The cigarettes in Study 1 contained tobacco mixed with cannabis; cigarettes in Study 2 contained only cannabis. Oral fluid specimens were collected from passive and active subjects with the Intercept Oral Specimen Collection Device for 1 h after smoking cessation while inside the van (Study 1) and up to 72 h (passive) or 8 h (active) outside the van. Additionally in Study 1, Intercept collectors were exposed to smoke in the van to assess environmental contamination during collection procedures. For Study 2, all oral fluid collections were outside the van following smoking cessation to minimize environmental contamination. Oral samples were analyzed with the Cannabinoids Intercept MICRO-PLATE EIA and quantitatively by gas chromatography-tandem mass spectrometry (GC-MS-MS). THC concentrations were adjusted for dilution (x 3). The screening and confirmation cutoff concentrations for THC in neat oral fluid were 3 ng/mL and 1.5 ng/mL, respectively. The limits of detection (LOD) and quantitation (LOQ) for THC in the GC-MS-MS assay were 0.3 and 0.75 ng/mL, respectively. Urine specimens were collected, screened (EMIT, 50

  5. Radiation effects after low dose chronic long-term exposure

    International Nuclear Information System (INIS)

    Fliedner, T.M.; Friesecke, I.

    1997-01-01

    This document approaches the radiation effects after low dose chronic long-term exposure, presenting examples occurred, the pathophysiologic mechanisms for cell system tolerance in elevated radiation fields, and the diagnostic and therapeutic possibilities

  6. Exposure to active and passive smoking among Greek pregnant women

    Directory of Open Access Journals (Sweden)

    Victoria G. Vivilaki

    2016-04-01

    Of 300 women recruited to the study 48 % reported tobacco use during the first trimester of pregnancy. Amongst participants who were tobacco users, 83.3 % reported making an attempt to quit but less than half (45.1 % were successful. Among women who continued to smoke during pregnancy the majority (55.8 % reported that they felt unable to quit, and 9.3 % reported that they considered smoking cessation was not an important health issue for them. Participants who continued to smoke during pregnancy were more likely to report fetal (χ2 = 11.41; df = 5; p < 0.05 and newborn complications (χ2 = 6.41; df = 2; p < 0.05, including preterm birth and low birth weight. Participants who reported that their partners were smokers were more likely to smoke throughout their pregnancy (χ2 = 14.62; df = 1; p < 0.001. High rates of second-hand smoke exposure were reported among both smoking and non-smoking women. Pregnant smokers had significantly higher levels of postnatal depressive and anxiety symptomatology, as measured using the EPDS, than non-smokers.

  7. A Comparison of Active and Passive Virtual Reality Exposure Scenarios to Elicit Social Anxiety

    Directory of Open Access Journals (Sweden)

    Yoones A. Sekhavat

    2017-06-01

    Full Text Available Social phobia is an anxiety disorder that results in an excessive and unreasonable fear of social situations. As a safe and controlled tool, Virtual Reality Exposure Therapy (VRET has been used to treat anxiety disorders and phobias. This paper aims to study whether VRET with active scenarios can challenge a person more than passive scenarios. By comparing participants who were exposed to active and passive scenarios in VRET, we show that active scenarios are more effective than passive scenarios to elicit social anxiety in healthy participants. We focus on eliciting social anxiety and creating the sense of presence as two parameters enhancing the efficacy of VRET scenarios.

  8. Passive exposures of children to volatile trihalomethanes during domestic cleaning activities of their parents

    Energy Technology Data Exchange (ETDEWEB)

    Andra, Syam S. [Water and Health Laboratory, Cyprus International Institute for Environmental and Public Health in association with Harvard School of Public Health, Cyprus University of Technology, Limassol (Cyprus); Harvard-Cyprus Program, Department of Environmental Health, Harvard School of Public Health, Boston, MA (United States); Charisiadis, Pantelis [Water and Health Laboratory, Cyprus International Institute for Environmental and Public Health in association with Harvard School of Public Health, Cyprus University of Technology, Limassol (Cyprus); Karakitsios, Spyros; Sarigiannis, Denis A. [Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, University Campus, Bldg. D, Rm 318, 54124 Thessaloniki (Greece); Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas, 57001 Thessaloniki-Thermi (Greece); Makris, Konstantinos C., E-mail: konstantinos.makris@cut.ac.cy [Water and Health Laboratory, Cyprus International Institute for Environmental and Public Health in association with Harvard School of Public Health, Cyprus University of Technology, Limassol (Cyprus)

    2015-01-15

    Domestic cleaning has been proposed as a determinant of trihalomethanes (THMs) exposure in adult females. We hypothesized that parental housekeeping activities could influence children's passive exposures to THMs from their mere physical presence during domestic cleaning. In a recent cross-sectional study (n=382) in Cyprus [41 children (<18y) and 341 adults (≥18y)], we identified 29 children who met the study's inclusion criteria. Linear regression models were applied to understand the association between children sociodemographic variables, their individual practices influencing ingestion and noningestion exposures to ΣTHMs, and their urinary THMs levels. Among the children-specific variables, age alone showed a statistically significant inverse association with their creatinine-adjusted urinary ΣTHMs (r{sub S}=−0.59, p<0.001). A positive correlation was observed between urinary ΣTHMs (ng g{sup −1}) of children and matched-mothers (r{sub S}=0.52, p=0.014), but this was not the case for their matched-fathers (r{sub S}=0.39, p=0.112). Time spent daily by the matched-mothers for domestic mopping, toilet and other cleaning activities using chlorine-based cleaning products was associated with their children's urinary THMs levels (r{sub S}=0.56, p=0.007). This trend was not observed between children and their matched-fathers urinary ΣTHMs levels, because of minimum amount of time spent by the latter in performing domestic cleaning. The proportion of variance of creatinine-unadjusted and adjusted urinary ΣTHMs levels in children that was explained by the matched-mothers covariates was 76% and 74% (p<0.001), respectively. A physiologically-based pharmacokinetic model adequately predicted urinary chloroform excretion estimates, being consistent with the corresponding measured levels. Our findings highlighted the influence of mothers' domestic cleaning activities towards enhancing passive THMs exposures of their children. The duration of such

  9. Passive exposures of children to volatile trihalomethanes during domestic cleaning activities of their parents

    International Nuclear Information System (INIS)

    Andra, Syam S.; Charisiadis, Pantelis; Karakitsios, Spyros; Sarigiannis, Denis A.; Makris, Konstantinos C.

    2015-01-01

    Domestic cleaning has been proposed as a determinant of trihalomethanes (THMs) exposure in adult females. We hypothesized that parental housekeeping activities could influence children's passive exposures to THMs from their mere physical presence during domestic cleaning. In a recent cross-sectional study (n=382) in Cyprus [41 children (<18y) and 341 adults (≥18y)], we identified 29 children who met the study's inclusion criteria. Linear regression models were applied to understand the association between children sociodemographic variables, their individual practices influencing ingestion and noningestion exposures to ΣTHMs, and their urinary THMs levels. Among the children-specific variables, age alone showed a statistically significant inverse association with their creatinine-adjusted urinary ΣTHMs (r S =−0.59, p<0.001). A positive correlation was observed between urinary ΣTHMs (ng g −1 ) of children and matched-mothers (r S =0.52, p=0.014), but this was not the case for their matched-fathers (r S =0.39, p=0.112). Time spent daily by the matched-mothers for domestic mopping, toilet and other cleaning activities using chlorine-based cleaning products was associated with their children's urinary THMs levels (r S =0.56, p=0.007). This trend was not observed between children and their matched-fathers urinary ΣTHMs levels, because of minimum amount of time spent by the latter in performing domestic cleaning. The proportion of variance of creatinine-unadjusted and adjusted urinary ΣTHMs levels in children that was explained by the matched-mothers covariates was 76% and 74% (p<0.001), respectively. A physiologically-based pharmacokinetic model adequately predicted urinary chloroform excretion estimates, being consistent with the corresponding measured levels. Our findings highlighted the influence of mothers' domestic cleaning activities towards enhancing passive THMs exposures of their children. The duration of such activities could be

  10. Brief postnatal exposure to phenobarbital impairs passive avoidance learning and sensorimotor gating in rats.

    Science.gov (United States)

    Gutherz, Samuel B; Kulick, Catherine V; Soper, Colin; Kondratyev, Alexei; Gale, Karen; Forcelli, Patrick A

    2014-08-01

    Phenobarbital is the most commonly utilized drug for the treatment of neonatal seizures. However, mounting preclinical evidence suggests that even brief exposure to phenobarbital in the neonatal period can induce neuronal apoptosis, alterations in synaptic development, and long-lasting changes in behavioral functions. In the present report, we treated neonatal rat pups with phenobarbital and evaluated behavior in adulthood. Pups were treated initially with a loading dose (80 mg/kg) on postnatal day (P)7 and with a lower dose (40 mg/kg) on P8 and P9. We examined sensorimotor gating (prepulse inhibition), passive avoidance, and conditioned place preference for cocaine when the animals reached adulthood. Consistent with our previous reports, we found that three days of neonatal exposure to phenobarbital significantly impaired prepulse inhibition compared with vehicle-exposed control animals. Using a step-though passive avoidance paradigm, we found that animals exposed to phenobarbital as neonates and tested as adults showed significant deficits in passive avoidance retention compared with matched controls, indicating impairment in associative memory and/or recall. Finally, we examined place preference conditioning in response to cocaine. Phenobarbital exposure did not alter the normal conditioned place preference associated with cocaine exposure. Our findings expand the profile of behavioral toxicity induced by phenobarbital. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Brief postnatal exposure to phenobarbital impairs passive-avoidance learning and sensorimotor gating in rats

    Science.gov (United States)

    Gutherz, Samuel B.; Kulick, Catherine V.; Soper, Colin; Kondratyev, Alexei; Gale, Karen; Forcelli, Patrick A.

    2014-01-01

    Phenobarbital is the most commonly utilized drug for the treatment of neonatal seizures. However, mounting preclinical evidence suggests that even brief exposure to phenobarbital in the neonatal period can induce neuronal apoptosis, alterations in synaptic development, and long-lasting changes in behavioral functions. In the present report, we treated neonatal rat pups with phenobarbital and evaluated behavior in adulthood. Pups were treated initially with a loading dose (80mg/kg) on postnatal day (P)7 and with a lower dose (40 mg/kg) on P8 and P9. We examined sensorimotor gating (prepulse inhibition), passive avoidance, and conditioned place preference to cocaine when the animals reached adulthood. Consistent with our previous reports, we found that three days of neonatal exposure to phenobarbital significantly impaired prepulse inhibition as compared to vehicle-exposed control animals. Using a step-though passive avoidance paradigm, we found that animals exposed to phenobarbital as neonates and tested as adults showed significant deficits in passive avoidance retention as compared to matched controls, indicating impairment in associative memory and/or recall. Finally, we examined place preference conditioning in response to cocaine. Phenobarbital exposure did not alter the normal conditioned place preference associated with cocaine exposure. Our findings expand the profile of behavioral toxicity induced by phenobarbital. PMID:25112558

  12. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap...

  13. Chronic Rumex Patientia Seed Feeding Improves Passive Avoidance Learning and Memory in Streptozotocin-Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Tourandokht Baluchnejadmojarad

    2010-08-01

    Full Text Available A B S T R A C T Introduction: Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Due to anti-diabetic and antioxidant activity of Rumex patientia (RP, this research study was conducted to evaluate the efficacy of chronic Rumex patientia feeding on alleviation of learning and memory disturbance in streptozotocindiabetic rats. Methods: Male Wistar rats were divided into control, diabetic, RP-treatedcontrol and -diabetic groups. For induction of diabetes, streptozotcin (STZ was administered at a dose of 60 mg/Kg. Meanwhile, RP-treated groups received RP seed powder mixed with standard pelleted food at a weight ratio of 6% for 4 weeks. For evaluation of learning and memory, initial latency (IL and step-through latency (STL were determined at the end of study using passive avoidance test. Results: It was found out that regarding initial latency, there was no significant difference among the groups. In addition, diabetic rats developed a significant impairment in retention and recall in passive avoidance test (p<0.01, as it is evident by a lower STL. Furthermore, RP treatment of diabetic rats did produce a significant improvement in retention and recall (p<0.05. Discussion: Taken together, chronic RP feeding could improve retention and recall capability in passive avoidance test in STZ-diabetic rats

  14. Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India

    Directory of Open Access Journals (Sweden)

    P A Mahesh

    2013-01-01

    Full Text Available Background & objectives: Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. Methods: A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. Results: A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. Interpretation & conclusions: The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

  15. Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India.

    Science.gov (United States)

    Mahesh, P A; Jayaraj, B S; Prabhakar, A K; Chaya, S K; Vijaysimha, R

    2013-01-01

    Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

  16. Passive dosing of triclosan in multi-generation tests with copepods - Stable exposure concentrations and effects at the low µg l-1 range

    DEFF Research Database (Denmark)

    Ribbenstedt, Anton; Mustajärvi, Lukas; Breitholtz, Magnus

    2017-01-01

    to test the applicability of passive dosing to maintain stable concentrations of the organochlorine bacteriocide triclosan in the water phase during a 6-week multi-generation population development test with the harpacticoid copepod Nitocra spinipes. Triclosan was loaded into silicone (1000 mg), which...... was used as passive dosing phase in the exposure vials. The distribution ratio for triclosan between silicone and water (Dsilicone-water ) was 10466 ± 1927. A population development test was conducted at three concentration levels of triclosan that were measured to be 3-5 µg L(-1) , 7-11 µg L(-1) and 16...... exerted on juvenile development. Progressively lower development index values in the populations exposed to increasing triclosan concentrations suggest developmental retardation. Our results further stress the need for chronic exposure during ecotoxicity testing in chemical risk assessment as even...

  17. Children's exposure to passive smoking in England since the 1980s: cotinine evidence from population surveys

    Science.gov (United States)

    Jarvis, Martin J; Goddard, Eileen; Higgins, Vanessa; Feyerabend, Colin; Bryant, Andrew; Cook, Derek G

    2000-01-01

    Objective To determine whether children's exposure to passive smoking has changed since the late 1980s. Design Cross sectional surveys of nationally representative samples of secondary school children carried out between 1988 and 1998 by Office for National Statistics. Setting England. Subjects Secondary school children aged 11-15. Main outcome measures Salivary cotinine concentrations in non-smoking children. Results Cotinine concentrations in all non-smoking children almost halved between 1988 and 1998, from a geometric mean of 0.96 (95% confidence interval 0.83 to 1.11) ng/ml in 1988 to 0.52 (0.43 to 0.62) ng/ml in 1998. This reduction was largely due to reductions in exposure in children from non-smoking households and to decreases in the percentage of parents who smoked. Children living with mothers or fathers who smoked experienced little reduction in exposure. Conclusions Exposure to passive smoking among children in England has approximately halved since the late 1980s. This reduction is partly explained by the fall in the percentage of both mothers and fathers who smoke and is also likely to reflect reductions of smoking in public places. However, there is only limited evidence that children from smoking households have experienced a reduction in exposure through parents' avoidance of smoking in their presence. PMID:10926591

  18. Chronic pesticide exposure and consequential keratectasia & corneal neovascularisation.

    Science.gov (United States)

    Sanyal, Shalini; Law, Atrayo; Law, Sujata

    2017-11-01

    Ocular toxicity as a consequence of chronic pesticide exposure is one of the health hazards caused due to extended exposure to pesticides. The cornea, due to its position as the outer ocular layer and its role in protecting the internal layers of the eye; is gravely affected by this xenobiotic insult to the eye, leading to ocular irritation and damage to normal vision. The deleterious effects of chronic pesticide exposure on the various corneal layers and the ocular risks involved therein, were explored by mimicking the on-field scenario. Cytological, histological and flowcytometric parameters were taken into consideration to determine the enhanced risk of corneal neovascularisation and keratectasia, specifically, keratoconus. Chronic exposure to pesticides leads to heightened ocular morbidity wherein there were visible pathophysiological changes to the ocular surface. The cornea was found to be adversely affected with visible protuberance in a cone-like shape, characteristic of keratoconus in a majority of the experimental animals. Further analyses revealed a detrimental impact on all the corneal layers and an amplified expression of inflammation markers such as TNF-α, VCAM-1 and ICAM-1. Additionally, it was found that post pesticide exposure, the corneal surface developed hypoxia, leading to a significant increase of angiogenesis promoting factors and consequential neovascularisation. Apart from ocular toxicity, chronic exposure to pesticides significantly increases the risks of keratectasia and corneal neovascularisation; disorders which lead to diminished vision and if untreated, blindness. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Silicone Wristband Passive Samplers Yield Highly Individualized Pesticide Residue Exposure Profiles.

    Science.gov (United States)

    Aerts, Raf; Joly, Laure; Szternfeld, Philippe; Tsilikas, Khariklia; De Cremer, Koen; Castelain, Philippe; Aerts, Jean-Marie; Van Orshoven, Jos; Somers, Ben; Hendrickx, Marijke; Andjelkovic, Mirjana; Van Nieuwenhuyse, An

    2018-01-02

    Monitoring human exposure to pesticides and pesticide residues (PRs) remains crucial for informing public health policies, despite strict regulation of plant protection product and biocide use. We used 72 low-cost silicone wristbands as noninvasive passive samplers to assess cumulative 5-day exposure of 30 individuals to polar PRs. Ethyl acetate extraction and LC-MS/MS analysis were used for the identification of PRs. Thirty-one PRs were detected of which 15 PRs (48%) were detected only in worn wristbands, not in environmental controls. The PRs included 16 fungicides (52%), 8 insecticides (26%), 2 herbicides (6%), 3 pesticide derivatives (10%), 1 insect repellent (3%), and 1 pesticide synergist (3%). Five detected pesticides were not approved for plant protection use in the EU. Smoking and dietary habits that favor vegetable consumption were associated with higher numbers and higher cumulative concentrations of PRs in wristbands. Wristbands featured unique PR combinations. Our results suggest both environment and diet contributed to PR exposure in our study group. Silicone wristbands could serve as sensitive passive samplers to screen population-wide cumulative dietary and environmental exposure to authorized, unauthorized and banned pesticides.

  20. Chronic bisphenol A exposure alters behaviors of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Wang, Ju; Wang, Xia; Xiong, Can; Liu, Jian; Hu, Bing; Zheng, Lei

    2015-01-01

    The adult zebrafish (Danio rerio) were exposed to treated-effluent concentration of bisphenol A (BPA) or 17β-estradiol (E2) for 6 months to evaluate their effects on behavioral characteristics: motor behavior, aggression, group preference, novel tank test and light/dark preference. E2 exposure evidently dampened fish locomotor activity, while BPA exposure had no marked effect. Interestingly, BPA-exposed fish reduced their aggressive behavior compared with control or E2. Both BPA and E2 exposure induced a significant decrease in group preference, as well as a weaker adaptability to new environment, exhibiting lower latency to reach the top, more entries to the top, longer time spent in the top, fewer frequent freezing, and fewer erratic movements. Furthermore, the circadian rhythmicity of light/dark preference was altered by either BPA or E2 exposure. Our results suggest that chronic exposure of treated-effluent concentration BPA or E2 induced various behavioral anomalies in adult fish and enhanced ecological risk to wildlife. - Highlights: • BPA exposure induces various adult behavioral anomalies. • BPA exposure decreases social interaction and environmental adaptation of zebrafish. • BPA exposure increases ecological risk to wildlife. - Chronic bisphenol A exposure alters zebrafish behaviors.

  1. Passive accessory joint mobilization in the multimodal management of chronic dysesthesia following thalamic stroke.

    Science.gov (United States)

    Griffin, Kristina; O'Hearn, Michael; Franck, Carla C; Courtney, Carol A

    2018-03-20

    Case Report. Stroke is the most common cause of long-term disability. Dysesthesia, an unpleasant sensory disturbance, is common following thalamic stroke and evidence-based interventions for this impairment are limited. The purpose of this case report was to describe a decrease in dysesthesia following manual therapy intervention in a patient with history of right lacunar thalamic stroke. A 66-year-old female presented with tingling and dysesthesia in left hemisensory distribution including left trunk and upper/lower extremities, limiting function. Decreased left shoulder active range of motion, positive sensory symptoms but no sensory loss in light touch was found. She denied pain and moderate shoulder muscular weakness was demonstrated. Laterality testing revealed right/left limb discrimination deficits and neglect-like symptoms were reported. Passive accessory joint motion assessment of glenohumeral and thoracic spine revealed hypomobility and provoked dysesthesia. Interventions included passive oscillatory joint mobilization of glenohumeral joint, thoracic spine, ribs and shoulder strengthening. After six sessions, shoulder function, active range of motion, strength improved and dysesthesia decreased. Global Rating of Change Scale was +5 and QuickDASH score decreased from 45% to 22% disability. Laterality testing was unchanged. Manual therapy may be a beneficial intervention in management of thalamic stroke-related dysesthesia. Implications for Rehabilitation While pain is common following thalamic stroke, patients may present with chronic paresthesia or dysesthesia, often in a hemisensory distribution. Passive movement may promote inhibition of hyperexcitable cortical pathways, which may diminish aberrant sensations. Passive oscillatory manual therapy may be an effective way to treat sensory disturbances such as paresthesias or dysesthesia.

  2. Impact of chronic and acute pesticide exposures on periphyton communities

    Energy Technology Data Exchange (ETDEWEB)

    Tlili, Ahmed, E-mail: ahmed.tlili@cemagref.fr [CEMAGREF, UR MAEP, 3 quai Chauveau CP 69336 Lyon Cedex 09 (France); Montuelle, Bernard, E-mail: bernard.montuelle@cemagref.fr [CEMAGREF, UR MAEP, 3 quai Chauveau CP 69336 Lyon Cedex 09 (France); INRA UMR CARRTEL, Laboratoire de Microbiologie Aquatique, BP 511, 74203, Thonon Cedex (France); Berard, Annette, E-mail: annette.berard@avignon.inra.fr [INRA UMR EMMAH 1114, Domaine Saint-Paul-Site Agroparc 84914 Avignon Cedex 9 (France); Bouchez, Agnes, E-mail: agnes.bouchez@thonon.inra.fr [INRA UMR CARRTEL, Laboratoire de Microbiologie Aquatique, BP 511, 74203, Thonon Cedex (France)

    2011-05-01

    Aquatic ecosystems face variable exposure to pesticides, especially during floodings which are associated with short bursts of high contaminant concentrations that influence biological systems. A study was undertaken to highlight the impact of the herbicide diuron applied in mixture with the fungicide tebuconazole on natural periphyton during flooding events. Periphyton were grown in two series of two lotic outdoor mesocosms: one series was non-contaminated while the other was exposed to chronic contamination. After 4 weeks, one channel of each series was exposed to three successive pulses, with each pulse followed by one week of recovery. Impacts on periphyton were assessed by using Denaturing Gel Gradient Electrophoresis to characterize eukaryotic community structure. At a functional scale, photosynthetic efficiency was quantified during each pulse, and the induced tolerance to diuron was estimated by performing short-term inhibition tests based on photosynthetic efficiency. Moreover, pesticide concentrations in the water column and periphyton matrix were measured. Diuron was adsorbed in the periphyton during each pulse and desorbed 13 h after pulse end. The different pulses affected the eukaryotic community structures of the control biofilms, but not of the chronically exposed ones. During the first pulse, photosynthetic efficiency was correlated with pesticide concentration in the water phase, and there was no difference between periphyton from chronically contaminated channels and control channels. However, during the second and third pulses, the photosynthetic efficiency of periphyton chronically exposed to pesticides appeared to be less impacted by the acute pulsed exposure of pesticide. These changes were consistent with the acquisition of induced tolerance to diuron since only after the third pulse that periphyton from chronic channel became tolerant to diuron. Our experimental study indicates that the effects of pulsed acute exposures to pesticides on

  3. Impact of chronic and acute pesticide exposures on periphyton communities

    International Nuclear Information System (INIS)

    Tlili, Ahmed; Montuelle, Bernard; Berard, Annette; Bouchez, Agnes

    2011-01-01

    Aquatic ecosystems face variable exposure to pesticides, especially during floodings which are associated with short bursts of high contaminant concentrations that influence biological systems. A study was undertaken to highlight the impact of the herbicide diuron applied in mixture with the fungicide tebuconazole on natural periphyton during flooding events. Periphyton were grown in two series of two lotic outdoor mesocosms: one series was non-contaminated while the other was exposed to chronic contamination. After 4 weeks, one channel of each series was exposed to three successive pulses, with each pulse followed by one week of recovery. Impacts on periphyton were assessed by using Denaturing Gel Gradient Electrophoresis to characterize eukaryotic community structure. At a functional scale, photosynthetic efficiency was quantified during each pulse, and the induced tolerance to diuron was estimated by performing short-term inhibition tests based on photosynthetic efficiency. Moreover, pesticide concentrations in the water column and periphyton matrix were measured. Diuron was adsorbed in the periphyton during each pulse and desorbed 13 h after pulse end. The different pulses affected the eukaryotic community structures of the control biofilms, but not of the chronically exposed ones. During the first pulse, photosynthetic efficiency was correlated with pesticide concentration in the water phase, and there was no difference between periphyton from chronically contaminated channels and control channels. However, during the second and third pulses, the photosynthetic efficiency of periphyton chronically exposed to pesticides appeared to be less impacted by the acute pulsed exposure of pesticide. These changes were consistent with the acquisition of induced tolerance to diuron since only after the third pulse that periphyton from chronic channel became tolerant to diuron. Our experimental study indicates that the effects of pulsed acute exposures to pesticides on

  4. Polyneuropathy caused by chronic exposure to trichloroethylene

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Y.; Iwata, M.; Hisanaga, M.; Ono, Y.; Shibata, E.; Huang, J.; Takegami, T.; Okamoto, S.; Koike, Y.

    1986-01-01

    A 51-year-old woman had been exposed to a high concentration of trichloroethylene for about 12 years. She had been employed in a factory where metal screws and washers for automobiles were manufactured. She had been engaged in dipping baskets of the screws and washers into an open bath of trichloroethylene. She first experienced symptoms of dizziness and headaches after degreasing the screws and washers. She also experienced sleepiness and fatigability, as well as paresthesia in the feet, hands and around the mouth. The muscle strength and tendon reflexes of the extremities were weakened: coordination was slightly clumsy and slow; and her gait was lightly paretic. Air samples were analyzed by gas chromatography and concentrations in the breathing zone of the worker were very high (579 and 792 ppm). It can be concluded from this investigation that peripheral nerve impairment is one of the important signs in chronic trichloroethylene poisoning. 15 references, 2 figures, 1 table.

  5. Resolving uncertainty in the spatial relationships between passive benzene exposure and risk of non-Hodgkin lymphoma.

    Science.gov (United States)

    Switchenko, Jeffrey M; Bulka, Catherine; Ward, Kevin; Koff, Jean L; Bayakly, A Rana; Ryan, P Barry; Waller, Lance A; Flowers, Christopher R

    2016-04-01

    Benzene is a known occupational carcinogen associated with increased risk of hematologic cancers, but the relationships between quantity of passive benzene exposure through residential proximity to toxic release sites, duration of exposure, lag time from exposure to cancer development, and lymphoma risk remain unclear. We collected release data through the Environmental Protection Agency's Toxics Release Inventory (TRI) from 1989 to 2003, which included location of benzene release sites, years when release occurred, and amount of release. We also collected data on incident cases of non-Hodgkin lymphoma (NHL) from the Georgia Comprehensive Cancer Registry (GCCR) for the years 1999-2008. We constructed distance-decay surrogate exposure metrics and Poisson and negative binomial regression models of NHL incidence to quantify associations between passive exposure to benzene and NHL risk and examined the impact of amount, duration of exposure, and lag time on cancer development. Akaike's information criteria (AIC) were used to determine the scaling factors for benzene dispersion and exposure periods that best predicted NHL risk. Using a range of scaling factors and exposure periods, we found that increased levels of passive benzene exposure were associated with higher risk of NHL. The best fitting model, with a scaling factor of 4 kilometers (km) and exposure period of 1989-1993, showed that higher exposure levels were associated with increased NHL risk (Level 4 (1.1-160kilograms (kg)) vs. Level 1: risk ratio 1.56 [1.44-1.68], Level 5 (>160kg) vs. Level 1: 1.60 [1.48-1.74]). Higher levels of passive benzene exposure are associated with increased NHL risk across various lag periods. Additional epidemiological studies are needed to refine these models and better quantify the expected total passive benzene exposure in areas surrounding release sites. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Contact highs and urinary cannabinoid excretion after passive exposure to marijuana smoke.

    Science.gov (United States)

    Cone, E J; Johnson, R E

    1986-09-01

    Five healthy men were passively exposed under pre- and postplacebo controlled conditions to sidestream smoke from four and 16 standard marijuana cigarettes (2.8% delta-9-tetrahydrocannabinol [delta-9-THC]) for 1 hour each day for 6 consecutive days. Subjective effects produced by the 16-cigarette exposure conditions were similar to those observed after active smoking of one 2.8% delta-9-THC marijuana cigarette. Effects after the four-cigarette condition were less pronounced. Concurrent physiologic measurements showed no clear trends or effects of smoke exposure for either condition. Daily mean plasma levels of delta-9-THC ranged from 2.4 to 7.4 ng/ml with an individual high of 18.8 ng/ml for the 16-cigarette condition. With the use of EMIT cannabinoid assays with 20 ng/ml (EMIT 20) and 100 ng/ml (EMIT 100) cutoffs, urines positive per subject under the four- and 16-cigarette passive exposure conditions were 4.6 +/- 2.2 and 35.2 +/- 3.8, respectively, for the EMIT 20 and 0.0 and 1.0 +/- 0.8, respectively, for the EMIT 100 assay. From the results of these studies, caution is clearly indicated for individuals who might be substantially exposed to heavy marijuana cigarette smoke environments and for those interpreting marijuana screening data.

  7. Fetal contamination with cadmium following chronic exposure of rat ...

    African Journals Online (AJOL)

    Fetal contamination with cadmium following chronic exposure of rat dams during gestation. ... African Journal of Applied Zoology and Environmental Biology ... It was concluded that cadmium, contrary to previous reports, can pass through the placenta in appreciable quantity to contaminate the fetus to possibly cause fetal ...

  8. The effect of passive exposure to tobacco smoke on perioperative respiratory complications and the duration of recovery.

    Science.gov (United States)

    Simsek, Esen; Karaman, Yucel; Gonullu, Mustafa; Tekgul, Zeki; Cakmak, Meltem

    2016-01-01

    The incidence of perioperative respiratory complications and postoperative care unit recovery time investigated in patients with passive tobacco smoke exposure according to the degree of exposure. Total 270 patients ranging in age from 18 to 60 years with the ASA physical status I or II exposed and not exposed to passive tobacco smoke received general anesthesia for various elective surgical operations evaluated for the study. Patients divided into two groups as exposed and non-exposed to passive tobacco smoke, those exposed to passive smoke are also divided into two groups according to the degree of exposure. Patients taken to the postoperative care unit (PACU) at the end of the operation and monitorized until Modified Aldrete's Scores became 9 and more. Respiratory complications evaluated and recorded in intraoperative and postoperative period. A total of 251 patients were enrolled; 63 (25.1%) patients had airway complications, 11 (4.4%) had complications intraoperatively and 52 (20.7%) patients had complications postoperatively. There has been found significant relation with passive tobacco smoke exposure and high incidences of perioperative and postoperative respiratory complications. The risk of cough, desaturation and hypersecretion complications were found to be increased depending on the degree of exposure. There was significant relation between the degree of passive smoke exposure and the duration of PACU stay. Passive tobacco smoke exposed general anesthesia receiving patients also regarding to the degree of exposure having high rates of perioperative respiratory complications and prolongation of PACU stays when compared with unexposed patients. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  9. [The effect of passive exposure to tobacco smoke on perioperative respiratory complications and the duration of recovery].

    Science.gov (United States)

    Simsek, Esen; Karaman, Yucel; Gonullu, Mustafa; Tekgul, Zeki; Cakmak, Meltem

    2016-01-01

    The incidence of perioperative respiratory complications and postoperative care unit recovery time investigated in patients with passive tobacco smoke exposure according to the degree of exposure. Total 270 patients ranging in age from 18 to 60 years with the ASA physical status I or II exposed and not exposed to passive tobacco smoke received general anesthesia for various elective surgical operations evaluated for the study. Patients divided into two groups as exposed and non-exposed to passive tobacco smoke, those exposed to passive smoke are also divided into two groups according to the degree of exposure. Patients taken to the postoperative care unit (PACU) at the end of the operation and monitorized until Modified Aldrete's Scores became 9 and more. Respiratory complications evaluated and recorded in intraoperative and postoperative period. A total of 251 patients were enrolled; 63 (25.1%) patients had airway complications, 11 (4.4%) had complications intraoperatively and 52 (20.7%) patients had complications postoperatively. There has been found significant relation with passive tobacco smoke exposure and high incidences of perioperative and postoperative respiratory complications. The risk of cough, desaturation and hypersecretion complications were found to be increased depending on the degree of exposure. There was significant relation between the degree of passive smoke exposure and the duration of PACU stay. Passive tobacco smoke exposed general anesthesia receiving patients also regarding to the degree of exposure having high rates of perioperative respiratory complications and prolongation of PACU stays when compared with unexposed patients. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  10. Absorption of nicotine and carbon monoxide from passive smoking under natural conditions of exposure.

    Science.gov (United States)

    Jarvis, M J; Russell, M A; Feyerabend, C

    1983-01-01

    Seven non-smokers were exposed to tobacco smoke under natural conditions for two hours in a public house. Measures of nicotine and cotinine in plasma, saliva, and urine and expired air carbon monoxide all showed reliable increases. The concentrations of carbon monoxide and nicotine after exposure averaged 15.7% and 7.5% respectively of the values found in heavy smokers. Although the increase in expired air carbon monoxide of 5.9 ppm was similar to increases in smokers after a single cigarette, the amount of nicotine absorbed was between a tenth and a third of the amount taken in from one cigarette. Since this represented a relatively extreme acute natural exposure, any health risks of passive smoking probably depend less on quantitative factors than on qualitative differences between sidestream and mainstream smoke. PMID:6648864

  11. Enhancement of exposure to radon progeny as a consequence of passive smoking

    International Nuclear Information System (INIS)

    Moghissi, A.A.; Seiler, M.C.

    1989-01-01

    Among indoor air pollutants, radon and tobacco smoke take dominant positions. Because radon decay products have a relatively short residence time in air, the extent of the equilibrium between radon and its daughter products is linearly proportional to the carcinogenic risk, at least at low exposure levels. The relevant factor is the equilibrium factor F. This paper discusses the enhancement of radon exposure as a result of the presence of particulate matter originating from tobacco smoke. The presence of tobacco smoke provides a mechanism for radon progeny to be attached to inhalable particles and to remain in indoor air for a prolonged time. The results of our study indicate a significant increase in F as a consequence of passive smoking. These modeling efforts are consistent with the experimental data reported previously

  12. Does chronic exposure to mobile phones affect cognition?

    Science.gov (United States)

    Mohan, Mamta; Khaliq, Farah; Panwar, Aprajita; Vaney, Neelam

    2016-01-01

    Summary Mobile phones form an integral part of our modern lifestyle. Following the drastic rise in mobile phone use in recent years, it has become important to study its potential public health impact. Amongst the various mobile phone health hazards, the most alarming is the possible effect on the brain. The aim of the present study was to explore whether chronic exposure to mobile phones affects cognition. Ninety subjects aged 17–25 years with normal hearing were recruited for the study and divided into three groups according to their duration of mobile phone use. No significant differences in N100, P200, N200, P300 latencies or N2-P300 amplitude were observed. Our results suggest that chronic mobile phone exposure does not have detrimental effects on cognition. PMID:27027894

  13. Welding fume exposure and chronic obstructive pulmonary disease in welders.

    Science.gov (United States)

    Koh, D-H; Kim, J-I; Kim, K-H; Yoo, S-W

    2015-01-01

    Occupational exposure is estimated to contribute 15% to the burden of chronic obstructive pulmonary disease (COPD). Welding fumes are suspected to accelerate the decline of lung function and development of COPD. To examine the relationship between welding fume exposure and COPD in Korean shipyard welders. The study involved a group of male welders working at two shipyards who underwent an annual health examination in 2010. Subjects completed a questionnaire about smoking habits and occupational history and a pulmonary function test (PFT) was carried out with strict quality control measures. Welding fume exposure concentrations were estimated using 884 measurements taken between 2002 and 2009 in one of the shipyards. Multiple linear and logistic regression was employed to evaluate the association between cumulative fume exposure and lung function parameters, controlling for age, height and cigarette smoking. Two hundred and forty subjects participated, with a mean age of 48 and mean work duration of 15 years. The mean cumulative fume exposure was 7.7mg/m(3). The prevalence of COPD was 15%. FEV1 and FVC showed non-significant negative correlations with cumulative fume exposure. Odds ratios of COPD were significantly elevated for the middle (3.9; 95% CI 1.4-13.3) and high exposure groups (3.8; 95% CI 1.03-16.2) compared with the low fume exposure group. Our findings support an association between welding fume exposure and increased risk of COPD. Further prospective study is needed to investigate whether this is a causal relationship. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Chronic obstructive pulmonary disease and occupational exposure to silica.

    Science.gov (United States)

    Rushton, Lesley

    2007-01-01

    Prolonged exposure to high levels of silica has long been known to cause silicosis This paper evaluates the evidence for an increased risk of chronic obstructive pulmonary disease (COPD) in occupations and industries in which exposure to crystalline silica is the primary exposure, with a focus on the magnitude of risks and levels of exposure causing disabling health effects. The literature suggests consistently elevated risks of developing COPD associated with silica exposure in several occupations, including the construction industry; tunneling; cement industry; brick manufacturing; pottery and ceramic work; silica sand, granite and diatomaceous earth industries; gold mining; and iron and steel founding, with risk estimates being high in some, even after taking into account the effect of confounders like smoking. Average dust levels vary from about 0.5 mg.m3 to over 10 mg.m3 and average silica levels from 0.04 to over 5 mg.m3, often well above occupational standards. Factors influencing the variation from industry to industry in risks associated with exposure to silica-containing dusts include (a) the presence of other minerals in the dust, particularly when associated with clay minerals; (b) the size of the particles and percentage of quartz; (c) the physicochemical characteristics, such as whether the dust is freshly fractured. Longitudinal studies suggest that loss of lung function occurs with exposure to silica dust at concentrations of between 0.1 and 0.2 mg.m3, and that the effect of cumulative silica dust exposure on airflow obstruction is independent of silicosis. Nevertheless, a disabling loss of lung function in the absence of silicosis would not occur until between 30 and 40 years exposure.

  15. Surface passivity largely governs the bioaccessibility of nickel-based powder particles at human exposure conditions.

    Science.gov (United States)

    Hedberg, Yolanda S; Herting, Gunilla; Latvala, Siiri; Elihn, Karine; Karlsson, Hanna L; Odnevall Wallinder, Inger

    2016-11-01

    The European chemical framework REACH requires that hazards and risks posed by chemicals, including alloys and metals, are identified and proven safe for humans and the environment. Therefore, differences in bioaccessibility in terms of released metals in synthetic biological fluids (different pH (1.5-7.4) and composition) that are relevant for different human exposure routes (inhalation, ingestion, and dermal contact) have been assessed for powder particles of an alloy containing high levels of nickel (Inconel 718, 57 wt% nickel). This powder is compared with the bioaccessibility of two nickel-containing stainless steel powders (AISI 316L, 10-12% nickel) and with powders representing their main pure alloy constituents: two nickel metal powders (100% nickel), two iron metal powders and two chromium metal powders. X-ray photoelectron spectroscopy, microscopy, light scattering, and nitrogen absorption were employed for the particle and surface oxide characterization. Atomic absorption spectroscopy was used to quantify released amounts of metals in solution. Cytotoxicity (Alamar blue assay) and DNA damage (comet assay) of the Inconel powder were assessed following exposure of the human lung cell line A549, as well as its ability to generate reactive oxygen species (DCFH-DA assay). Despite its high nickel content, the Inconel alloy powder did not release any significant amounts of metals and did not induce any toxic response. It is concluded, that this is related to the high surface passivity of the Inconel powder governed by its chromium-rich surface oxide. Read-across from the pure metal constituents is hence not recommended either for this or any other passive alloy. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  16. Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhenhua [Department of Anatomy, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China 230032 (China); Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Zhang, Zhuo; Shi, Xianglin [Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States)

    2016-10-01

    Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

  17. Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

    International Nuclear Information System (INIS)

    Ren, Zhenhua; Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A.; Ke, Zun-ji; Zhang, Zhuo; Shi, Xianglin; Luo, Jia

    2016-01-01

    Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

  18. The passive control of air pollution exposure in Dublin, Ireland: a combined measurement and modelling case study.

    Science.gov (United States)

    Gallagher, J; Gill, L W; McNabola, A

    2013-08-01

    This study investigates the potential real world application of passive control systems to reduce personal pollutant exposure in an urban street canyon in Dublin, Ireland. The implementation of parked cars and/or low boundary walls as a passive control system has been shown to minimise personal exposure to pollutants on footpaths in previous investigations. However, previous research has been limited to generic numerical modelling studies. This study combines real-time traffic data, meteorological conditions and pollution concentrations, in a real world urban street canyon before and after the implementation of a passive control system. Using a combination of field measurements and numerical modelling this study assessed the potential impact of passive controls on personal exposure to nitric oxide (NO) concentrations in the street canyon in winter conditions. A calibrated numerical model of the urban street canyon was developed, taking into account the variability in traffic and meteorological conditions. The modelling system combined the computational fluid dynamic (CFD) simulations and a semi-empirical equation, and demonstrated a good agreement with measured field data collected in the street canyon. The results indicated that lane distribution, fleet composition and vehicular turbulence all affected pollutant dispersion, in addition to the canyon geometry and local meteorological conditions. The introduction of passive controls displayed mixed results for improvements in air quality on the footpaths for different wind and traffic conditions. Parked cars demonstrated the most comprehensive passive control system with average improvements in air quality of up to 15% on the footpaths. This study highlights the potential of passive controls in a real street canyon to increase dispersion and improve air quality at street level. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Effects in Plant Populations Resulting from Chronic Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Geras' kin, Stanislav A.; Volkova, Polina Yu.; Vasiliyev, Denis V.; Dikareva, Nina S.; Oudalova, Alla A. [Russian Institute of Agricultural Radiology and Agroecology, 249032, Obninsk (Russian Federation)

    2014-07-01

    Human industrial activities have left behind a legacy of ecosystems strongly impacted by a wide range of contaminants, including radionuclides. Phyto-toxic effects of acute impact are well known, but the consequences of long-term chronic exposure to low pollutant concentrations is neither well understood nor adequately included in risk assessments. To understand effects of real-world contaminant exposure properly we must pay attention to what is actually going on in the field. However, for many wildlife groups and endpoints, there are no, or very few, studies that link accumulation, chronic exposure and biological effects in natural settings. To fill the gaps, results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hair-grass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate effects of long-term chronic exposure to radionuclides are discussed. Because each impacted site developed in its own way due to a unique history of events, the experience from one case study is rarely directly applicable to another situation. In spite of high heterogeneity in response, we have detected several general patterns. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic alterations and genetic diversity. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage were accompanied by decrease in reproductive ability. In less contaminated sites, because of the scarcity of data available, it is impossible to establish exactly the relationship between cytogenetic effects and reproductive ability. Radioactive contamination of the plants

  20. Chronic exposure to environmental levels of tribromophenol impairs zebrafish reproduction

    International Nuclear Information System (INIS)

    Deng Jun; Liu Chunsheng; Yu Liqin; Zhou Bingsheng

    2010-01-01

    Tribromophenol (2,4,6-TBP) is ubiquitously found in aquatic environments and biota. In this study, we exposed zebrafish embryos (F 0 ; 2'''' days post-fertilization, dpf) to environmental concentration (0.3 μg/L) and a higher concentration (3.0 μg/L) of TBP and assessed the impact of chronic exposure (120 dpf) on reproduction. TBP exposure did not cause a significant increase in the malformation and reduction in the survival in the F 0 -generation fish. After TBP exposure, the plasma testosterone and estradiol levels significantly increased in males and decreased in females. The transcription of steroidogenic genes (3β-HSD, 17β-HSD, CYP17, CYP19A, CYP19B) was significantly upregulated in the brain and testes in males and downregulated in the brain and ovary in females. TBP exposure significantly downregulated and upregulated the expression of VTG in the liver of female and male fish, respectively. Meanwhile, TBP exposure altered the sex ratio toward a male-dominant state. The F 1 -generation larvae exhibited increased malformation, reduced survival, and retarded growth, suggesting that TBP in the aquatic environment has significant adverse effects on fish population.

  1. Exposure to Outdoor Air Pollution and Chronic Bronchitis in Adults: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    P Salameh

    2012-08-01

    Full Text Available Background: Although Lebanon is a highly polluted country, so far no study has specifically been designed to assess the association between outdoor air pollution and chronic bronchitis in this country. Objective: To assess the association between exposure to outdoor air pollution and chronic bronchitis in Lebanon. Methods: A pilot case-control study was conducted in two tertiary care hospitals. Cases consisted of patients diagnosed with chronic bronchitis by a pulmonologist and those epidemiologically confirmed. Controls included individuals free of any respiratory signs or symptoms. After obtaining informed consent, a standardized questionnaire was administered. Results: Bivariate, stratified (over smoking status and gender and multivariate analyses revealed that passive smoking at home (ORa: 2.56, 95% CI: 1.73–3.80 and at work (ORa: 1.89, 95% CI: 1.13–3.17; older age (ORa: 1.75, 95% CI: 1.55–2.39; lower education (ORa: 1.44, 95% CI: 1.21–1.72; living close to a busy road (ORa: 1.95, 95% CI: 1.31– 2.89 and to a local power plant (ORa: 1.62, 95% CI: 1.07–2.45; and heating home by hot air conditioning (ORa: 1.85, 95% CI: 1.00–3.43 were moderately associated with chronic bronchitis; an inverse association was found with heating home electrically (ORa: 0.58, 95% CI: 0.39–0.85. A positive dose-effect relationship was observed in those living close to a busy road and to a local diesel exhaust source. Conclusion: Chronic bronchitis is associated with outdoor air pollution.

  2. Factors Associated with Exposure to Passive Smoking among 12-18 year-old Students in Athens and Thessaloniki, Greece

    Directory of Open Access Journals (Sweden)

    Andreas S Lappas

    2015-11-01

    Passive-smoking exposure is prevalent among the student population in Greece, despite the New Anti-Smoking Legislation that came into effect in July 2009. Our findings indicate that enforcement of the law and additional public health initiatives must be implemented.

  3. Effect of uranium chronic exposure on the moult in crayfish

    International Nuclear Information System (INIS)

    Simon, O.; Camilleri, V.; Garnier-Laplace, J.

    2004-01-01

    Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

  4. Effect of uranium chronic exposure on the moult in crayfish

    Energy Technology Data Exchange (ETDEWEB)

    Simon, O.; Camilleri, V.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

  5. The passive control of air pollution exposure in Dublin, Ireland: A combined measurement and modelling case study

    International Nuclear Information System (INIS)

    Gallagher, J.; Gill, L.W.; McNabola, A.

    2013-01-01

    This study investigates the potential real world application of passive control systems to reduce personal pollutant exposure in an urban street canyon in Dublin, Ireland. The implementation of parked cars and/or low boundary walls as a passive control system has been shown to minimise personal exposure to pollutants on footpaths in previous investigations. However, previous research has been limited to generic numerical modelling studies. This study combines real-time traffic data, meteorological conditions and pollution concentrations, in a real world urban street canyon before and after the implementation of a passive control system. Using a combination of field measurements and numerical modelling this study assessed the potential impact of passive controls on personal exposure to nitric oxide (NO) concentrations in the street canyon in winter conditions. A calibrated numerical model of the urban street canyon was developed, taking into account the variability in traffic and meteorological conditions. The modelling system combined the computational fluid dynamic (CFD) simulations and a semi-empirical equation, and demonstrated a good agreement with measured field data collected in the street canyon. The results indicated that lane distribution, fleet composition and vehicular turbulence all affected pollutant dispersion, in addition to the canyon geometry and local meteorological conditions. The introduction of passive controls displayed mixed results for improvements in air quality on the footpaths for different wind and traffic conditions. Parked cars demonstrated the most comprehensive passive control system with average improvements in air quality of up to 15% on the footpaths. This study highlights the potential of passive controls in a real street canyon to increase dispersion and improve air quality at street level. - Highlights: • Parked cars and LBWs were assessed as passive controls in an urban street canyon. • The calibrated model combined CFD

  6. The passive control of air pollution exposure in Dublin, Ireland: A combined measurement and modelling case study

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, J., E-mail: j.gallagher@bangor.ac.uk [School of Energy, Natural Resources and Geography, Bangor University (United Kingdom); Gill, L.W.; McNabola, A. [Dept. of Civil, Structural and Environmental Engineering, Trinity College Dublin (Ireland)

    2013-08-01

    This study investigates the potential real world application of passive control systems to reduce personal pollutant exposure in an urban street canyon in Dublin, Ireland. The implementation of parked cars and/or low boundary walls as a passive control system has been shown to minimise personal exposure to pollutants on footpaths in previous investigations. However, previous research has been limited to generic numerical modelling studies. This study combines real-time traffic data, meteorological conditions and pollution concentrations, in a real world urban street canyon before and after the implementation of a passive control system. Using a combination of field measurements and numerical modelling this study assessed the potential impact of passive controls on personal exposure to nitric oxide (NO) concentrations in the street canyon in winter conditions. A calibrated numerical model of the urban street canyon was developed, taking into account the variability in traffic and meteorological conditions. The modelling system combined the computational fluid dynamic (CFD) simulations and a semi-empirical equation, and demonstrated a good agreement with measured field data collected in the street canyon. The results indicated that lane distribution, fleet composition and vehicular turbulence all affected pollutant dispersion, in addition to the canyon geometry and local meteorological conditions. The introduction of passive controls displayed mixed results for improvements in air quality on the footpaths for different wind and traffic conditions. Parked cars demonstrated the most comprehensive passive control system with average improvements in air quality of up to 15% on the footpaths. This study highlights the potential of passive controls in a real street canyon to increase dispersion and improve air quality at street level. - Highlights: • Parked cars and LBWs were assessed as passive controls in an urban street canyon. • The calibrated model combined CFD

  7. Effects of chronic radiation exposure on the reproduction of dogs

    International Nuclear Information System (INIS)

    Shifrine, M.; Kawakami, T.G.; Rasmussen, C.

    1984-01-01

    During studies on radiation leukemogenesis 7 dogs were exposed to 4.4 R/day starting at 150 days of age. Three of these dogs were females. To determine whether the exposure to chronic irradiation affected their reproductive capacity the three bitches were bred. Two of the bitches did not conceive, and one of these died shortly thereafter from myeloproliferative disease (MPD) which could have been a factor. The third bitch whelped 7 pups, one of which died shortly after birth, and the other 6 are healthy 2 months after birth. 1 table

  8. The effect of chronic exposure to fatty acids

    DEFF Research Database (Denmark)

    Xiao, J.; Gregersen, S.; Kruhøffer, Mogens

    2001-01-01

    Fatty acids affect insulin secretion of pancreatic beta-cells. Investigating gene expression profiles may help to characterize the underlying mechanism. INS-1 cells were cultured with palmitate (0, 50, and 200 microM) for up to 44 d. Insulin secretion and expressions of 8740 genes were studied. We...... 44, respectively. Genes involved in fatty acid oxidation were up-regulated, whereas those involved in glycolysis were down-regulated with 200 microM palmitate. A suppression of insulin receptor and insulin receptor substate-2 gene expression was found on d 44 in cells cultured at 200 microM palmitate....... In conclusion, chronic exposure to low palmitate alters insulin secretion as well as gene expression. The number of genes that changed expression was palmitate dose and exposure time dependent. Randle's fatty acid-glucose cycle seems to be operative on the gene transcription level. A modification of expression...

  9. MBST-exposure opportunities as a monotherapy of chronic dorsalgia

    Directory of Open Access Journals (Sweden)

    Levchenko КК

    2017-09-01

    Full Text Available The aim: to analyze the clinical effect of MBST-exposure monotherapy, a magnetic resonance method, on the pain syndrome caused by degenerative dystrophic changes of vertebral column structures. Material and Methods. 132 patients both male and female with cervical and lumbar dorsopathy were enrolled into the study. Treatment course included 9 sessions of 60 min. daily. MRI-results of corresponding spine regions and visual analogue pain intensity scale were used as assessment tools for treatment efficiency before, immediately after, 3, 6 and 12 months after MBST-treatment. Results. The objective results of structural transformation of pathological formations in vertebral motional segments correlated with significant decrease of pain syndrome at all stages of control tests. Conclusion. MBST-exposure is an effective method of non-invasive, notouch monotherapy for patients with chronic dorsalgia caused by degenerative dorsopathy.

  10. Impacts of chronic sublethal exposure to clothianidin on winter honeybees.

    Science.gov (United States)

    Alkassab, Abdulrahim T; Kirchner, Wolfgang H

    2016-07-01

    A wide application of systemic pesticides and detection of their residues in bee-collected pollen and nectar at sublethal concentrations led to the emergence of concerns about bees' chronic exposure and possible sublethal effects on insect pollinators. Therefore, special attention was given to reducing unintentional intoxications under field conditions. The sensitivity of winter bees throughout their long lifespan to residual exposure of pesticides is not well known, since most previous studies only looked at the effects on summer bees. Here, we performed various laboratory bioassays to assess the effects of clothianidin on the survival and behavior of winter bees. Oral lethal and sublethal doses were administered throughout 12-day. The obtained LD50 values at 48, 72, 96 h and 10 days were 26.9, 18.0, 15.1 and 9.5 ng/bee, respectively. Concentrations <20 µg/kg were found to be sublethal. Oral exposure to sublethal doses was carried out for 12-day and, the behavioral functions were tested on the respective 13th day. Although slight reductions in the responses at the concentrations 10 and 15 µg/kg were observed, all tested sublethal concentrations had showed non-significant effects on the sucrose responsiveness, habitation of the proboscis extension reflex and olfactory learning performance. Nevertheless, chronic exposure to 15 µg/kg affected the specificity of the early long-term memory (24 h). Since the tested concentrations were in the range of field-relevant concentrations, our results strongly suggest that related-effects on winter and summer bees' sensitivity should also be studied under realistic conditions.

  11. Passive Smoke Exposure and Its Effects on Cognition, Sleep, and Health Outcomes in Overweight and Obese Children.

    Science.gov (United States)

    Davis, Catherine L; Tingen, Martha S; Jia, Jenny; Sherman, Forrest; Williams, Celestine F; Bhavsar, Kruti; Wood, Nancy; Kobleur, Jessica; Waller, Jennifer L

    2016-04-01

    Passive smoke exposure (PSE) may be a risk factor for childhood overweight and obesity and is associated with worse neurocognitive development, cognition, and sleep in children. The purpose of the study is to examine the effects of PSE on adiposity, cognition, and sleep in overweight and obese children using an objective measure of PSE. Overweight or obese children (n = 222) aged 7-11 (9.4 ± 1.1 years; 58% black; 58% female; 85% obese) were recruited from schools near Augusta, Georgia, over the course of the school year from 2003-2006 for a clinical trial, with data analyzed in 2009-2010. Passive smoke exposure was measured with plasma cotinine. Health, cognitive, and sleep measures and parent report of smoke exposure were obtained. Overweight and obese children with PSE had greater overall and central adiposity than nonexposed overweight and obese children (p prevent adverse health outcomes related to tobacco use and obesity.

  12. The relationship between amygdala activation and passive exposure time to an aversive cue during a continuous performance task.

    Directory of Open Access Journals (Sweden)

    Irina A Strigo

    2010-11-01

    Full Text Available The allocation of attention modulates negative emotional processing in the amygdala. However, the role of passive exposure time to emotional signals in the modulation of amygdala activity during active task performance has not been examined. In two functional Magnetic Resonance Imaging (fMRI experiments conducted in two different groups of healthy human subjects, we examined activation in the amygdala due to cued anticipation of painful stimuli while subjects performed a simple continuous performance task (CPT with either a fixed or a parametrically varied trial duration. In the first experiment (N = 16, engagement in the CPT during a task with fixed trial duration produced the expected attenuation of amygdala activation, but close analysis suggested that the attenuation occurred during the period of active engagement in CPT, and that amygdala activity increased proportionately during the remainder of each trial, when subjects were passively exposed to the pain cue. In the second experiment (N = 12, the duration of each trial was parametrically varied, and we found that amygdala activation was linearly related to the time of passive exposure to the anticipatory cue. We suggest that amygdala activation during negative anticipatory processing depends directly on the passive exposure time to the negative cue.

  13. Human Physiological Responses to Acute and Chronic Cold Exposure

    Science.gov (United States)

    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.

  14. A population-based exposure assessment methodology for carbon monoxide: Development of a carbon monoxide passive sampler and occupational dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael G. [Univ. of California, Berkeley, CA (United States)

    1997-09-01

    Two devices, an occupational carbon monoxide (CO) dosimeter (LOCD), and an indoor air quality (IAQ) passive sampler were developed for use in population-based CO exposure assessment studies. CO exposure is a serious public health problem in the U.S., causing both morbidity and mortality (lifetime mortality risk approximately 10{sup -4}). Sparse data from population-based CO exposure assessments indicate that approximately 10% of the U.S. population is exposed to CO above the national ambient air quality standard. No CO exposure measurement technology is presently available for affordable population-based CO exposure assessment studies. The LOCD and IAQ Passive Sampler were tested in the laboratory and field. The palladium-molybdenum based CO sensor was designed into a compact diffusion tube sampler that can be worn. Time-weighted-average (TWA) CO exposure of the device is quantified by a simple spectrophotometric measurement. The LOCD and IAQ Passive Sampler were tested over an exposure range of 40 to 700 ppm-hours and 200 to 4200 ppm-hours, respectively. Both devices were capable of measuring precisely (relative standard deviation <20%), with low bias (<10%). The LOCD was screened for interferences by temperature, humidity, and organic and inorganic gases. Temperature effects were small in the range of 10°C to 30°C. Humidity effects were low between 20% and 90% RH. Ethylene (200 ppm) caused a positive interference and nitric oxide (50 ppm) caused a negative response without the presence of CO but not with CO.

  15. Chronic Kidney Disease and Exposure to Nephrotoxic Metals

    Science.gov (United States)

    Orr, Sarah E.; Bridges, Christy C.

    2017-01-01

    Chronic kidney disease (CKD) is a common progressive disease that is typically characterized by the permanent loss of functional nephrons. As injured nephrons become sclerotic and die, the remaining healthy nephrons undergo numerous structural, molecular, and functional changes in an attempt to compensate for the loss of diseased nephrons. These compensatory changes enable the kidney to maintain fluid and solute homeostasis until approximately 75% of nephrons are lost. As CKD continues to progress, glomerular filtration rate decreases, and remaining nephrons are unable to effectively eliminate metabolic wastes and environmental toxicants from the body. This inability may enhance mortality and/or morbidity of an individual. Environmental toxicants of particular concern are arsenic, cadmium, lead, and mercury. Since these metals are present throughout the environment and exposure to one or more of these metals is unavoidable, it is important that the way in which these metals are handled by target organs in normal and disease states is understood completely. PMID:28498320

  16. Enclosure design for flock-level, chronic exposure of birds to air contaminant mixtures.

    Science.gov (United States)

    North, Michelle A; Kinniburgh, David W; Smits, Judit E G

    2018-05-01

    The objective of this study was to design an enclosure suitable for studying the ecotoxicological effects of vehicle emissions on groups of wild birds without compromising welfare. Two, adjacent enclosures sheltered from sunlight, wind and rain, were bird-proofed and wrapped with thick polyethylene sheeting. Emissions were directed into the treatment enclosure from the exhaust of a light-duty gasoline truck, using flexible, heat-proof pipe, with joins sealed to prevent leakage. During active exposure, the engine was idled for 5 h/day, 6 days/week for 4 weeks. Fans maintained positive pressure (controls) and negative pressure (treatment), preventing cross-contamination of enclosures and protecting investigators. Four sets of passive, badge-type samplers were distributed across each enclosure, measuring nitrogen dioxide, sulfur dioxide and volatile organic compounds (NO 2 , SO 2 and VOCs, respectively), and were complemented by active monitors measuring VOCs and particulate matter (2.5 µm diameter, PM 2.5 ). We found that the concentrations of NO 2 , SO 2 and PM 2.5 were not different between treatment and control enclosures. Volatile organic compounds (e.g. benzene, toluene, ethylbenzene and xylenes) were approximately six times higher in the treatment enclosure than control (13.23 and 2.13 µg m -1 , respectively). In conclusion, this represents a successful, practical design for studying the effects of sub-chronic to chronic exposure to realistic mixtures of vehicle exhaust contaminants, in groups of birds. Recommended modifications for future research include a chassis dynamometer (vehicle treadmill), to better replicate driving conditions including acceleration and deceleration.

  17. Monte Carlo and analytical model predictions of leakage neutron exposures from passively scattered proton therapy

    International Nuclear Information System (INIS)

    Pérez-Andújar, Angélica; Zhang, Rui; Newhauser, Wayne

    2013-01-01

    Purpose: Stray neutron radiation is of concern after radiation therapy, especially in children, because of the high risk it might carry for secondary cancers. Several previous studies predicted the stray neutron exposure from proton therapy, mostly using Monte Carlo simulations. Promising attempts to develop analytical models have also been reported, but these were limited to only a few proton beam energies. The purpose of this study was to develop an analytical model to predict leakage neutron equivalent dose from passively scattered proton beams in the 100-250-MeV interval.Methods: To develop and validate the analytical model, the authors used values of equivalent dose per therapeutic absorbed dose (H/D) predicted with Monte Carlo simulations. The authors also characterized the behavior of the mean neutron radiation-weighting factor, w R , as a function of depth in a water phantom and distance from the beam central axis.Results: The simulated and analytical predictions agreed well. On average, the percentage difference between the analytical model and the Monte Carlo simulations was 10% for the energies and positions studied. The authors found that w R was highest at the shallowest depth and decreased with depth until around 10 cm, where it started to increase slowly with depth. This was consistent among all energies.Conclusion: Simple analytical methods are promising alternatives to complex and slow Monte Carlo simulations to predict H/D values. The authors' results also provide improved understanding of the behavior of w R which strongly depends on depth, but is nearly independent of lateral distance from the beam central axis

  18. Safety assessment of chronic oral exposure to iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Chamorro, Susana; Vaquero, María Pilar; Brenes, Agustín; Gutiérrez, Lucía; Salas, Gorka; Luengo, Yurena; Verdoy, Dolores; José Teran, Francisco

    2015-01-01

    Iron oxide nanoparticles with engineered physical and biochemical properties are finding a rapidly increasing number of biomedical applications. However, a wide variety of safety concerns, especially those related to oral exposure, still need to be addressed for iron oxide nanoparticles in order to reach clinical practice. Here, we report on the effects of chronic oral exposure to low doses of γ-Fe 2 O 3 nanoparticles in growing chickens. Animal observation, weight, and diet intake reveal no adverse signs, symptoms, or mortality. No nanoparticle accumulation was observed in liver, spleen, and duodenum, with feces as the main excretion route. Liver iron level and duodenal villi morphology reflect the bioavailability of the iron released from the partial transformation of γ-Fe 2 O 3 nanoparticles in the acid gastric environment. Duodenal gene expression studies related to the absorption of iron from γ-Fe 2 O 3 nanoparticles indicate the enhancement of a ferric over ferrous pathway supporting the role of mucins. Our findings reveal that oral administration of iron oxide nanoparticles is a safe route for drug delivery at low nanoparticle doses. (paper)

  19. Prepubertal gynecomastia and chronic lavender exposure: report of three cases.

    Science.gov (United States)

    Diaz, Alejandro; Luque, Laura; Badar, Zain; Kornic, Steve; Danon, Marco

    2016-01-01

    Prepubertal gynecomastia is a rare condition characterized by the growth of breast tissue in males as a consequence of early exposure to sexual hormones. When this condition is present, pathological sources of testosterone/estrogen production, such as adrenal or gonadal tumors must be searched for. A few reports have described an association between gynecomastia and substances that produce stimulation of the estrogen receptor, such as lavender and tea tree oil. Here we describe the cases of three boys who presented with prepubertal gynecomastia and were chronically exposed to lavender. Two of these boys were exposed to a cologne, named agua de violetas, used by Hispanic communities in the US, and in their countries of origin. We studied a sample of the cologne used by one of the patients. Analysis of the chemical composition of the agua de violetas cologne was performed using high-performance liquid chromatography as well as off-line mass spectrometric detection. All these, combined with the physical appearance and the smell, determined that the cologne had lavender as an ingredient. Exposure to estrogenic substances, such as lavender, should be explored in children presenting with prepubertal gynecomastia/thelarche.

  20. CHRONIC DIETARY EXPOSURE WITH INTERMITTENT SPIKE DOSES OF CHLORPYRIFOS FAILS TO ALTER FLASH OR PATTERN REVERSAL EVOKED POTENTIALS IN RATS.

    Science.gov (United States)

    Human exposure to pesticides is often characterized by chronic low level exposure with intermittent spiked higher exposures. Visual disturbances are often reported following exposure to xenobiotics, and cholinesterase-inhibiting compounds have been reported to alter visual functi...

  1. Chronic obstructive pulmonary disease (COPD and occupational exposures

    Directory of Open Access Journals (Sweden)

    Zeni Elena

    2006-06-01

    Full Text Available Abstract Chronic obstructive pulmonary disease (COPD is one of the leading causes of morbidity and mortality in both industrialized and developing countries. Cigarette smoking is the major risk factor for COPD. However, relevant information from the literature published within the last years, either on general population samples or on workplaces, indicate that about 15% of all cases of COPD is work-related. Specific settings and agents are quoted which have been indicated or confirmed as linked to COPD. Coal miners, hard-rock miners, tunnel workers, concrete-manufacturing workers, nonmining industrial workers have been shown to be at highest risk for developing COPD. Further evidence that occupational agents are capable of inducing COPD comes from experimental studies, particularly in animal models. In conclusion, occupational exposure to dusts, chemicals, gases should be considered an established, or supported by good evidence, risk factor for developing COPD. The implications of this substantial occupational contribution to COPD must be considered in research planning, in public policy decision-making, and in clinical practice.

  2. Chronic particulate exposure, mortality and cardiovascular outcomes in the nurses health study

    Science.gov (United States)

    Adverse health effects of exposures to acute air pollution have been well studied. Fewer studies have examined effects of chronic exposure. Previous studies used exposure estimates for narrow time periods and were limited by the geographic distribution of pollution monitors. This...

  3. Late health effects of chronic radiation exposure of bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Yarmoshenko, Ilia V.; Malinovsky, Georgy P.; Konshina, Lidia G.; Zhukovsky, Michael V. [Institute of Industrial Ecology UB RAS, 620219, 20, Sophy Kovalevskoy St., Ekaterinburg (Russian Federation); Tuzankina, Irina A. [Institute of Immunology and Physiology UB RAS, 620049, 106, Pervomayskaya St., Ekaterinburg (Russian Federation)

    2014-07-01

    infectious etiology, which are unexpected due to low doses absorbed in those organs and tissues. To analyze the unexpected results recent findings on strong attributability of stomach, liver and cervix cancers to bacterial and viral infections was taken into account. According to IARC, stomach cancer relative risk associated with helicobacter pillory is 5.6, liver cancer relative risks associated with HBV and HCV are 23 and 17 respectively, cervix cancer relative risk associated with HPV is >100. At the same time association of lung cancer, colon cancer and some other common malignancies with infections is either not established or of low significance. To explain observed effects we suggested that excess mortality due to cancer and non-cancer diseases of infectious etiology is associated with radiation exposure of bone marrow due to Sr-90. Irradiation of hematopoietic stem cells and progenitor cells damages hematopoiesis and suppresses the immune response. Secondary immune deficiency induced by chronic radiation increases susceptibility to the bacterial and viral infections. Such late effect of radiation exposure can be considered within the concept of deterministic tissue reactions. (Under support of UB RAS project 12-P-2-1033). (authors)

  4. Growth of fullerene on Ag and hydrogen-passivated Si substrates: Effect of electron beam exposure on growth modes

    International Nuclear Information System (INIS)

    Rundhe, M.V.; Dev, B.N.

    2008-01-01

    We have used Auger electron spectroscopy (AES) to investigate the effect of electron beam exposure on growth modes of fullerene (C 60 ) on substrates like Ag and hydrogen-passivated Si(1 1 1). The electron beam comprises of 3.4 keV electrons, which are used in the AES study. To investigate the effect, Auger signal (AS) vs. deposition time (t) measurements were conducted in a sequential mode, i.e., alternating deposition of C 60 and analysis using the electron beam. Duration of AES data collection after each deposition was the duration of exposure to electron beam in this experiment. For the growth study of C 60 on Ag, three AS-t plots were recorded for three different durations of exposure to electron beam. Changes in the AS-t plot, depending on the duration of exposure to the electron beam, reflect the electron beam-induced damage. Electron beam-induced damages of C 60 produce carbon materials of different densities and consequently transmission coefficient (α) of Auger electron through this material changes. In order to fit the AES (AS vs. t) data a model has been used which simultaneously provides the growth mode and the transmission coefficient. Observation of an increasing transmission coefficient with the increasing duration of exposure to the electron beam from α=0.34 to 0.60 indicates the change of the nature of the carbon material due to the partial damage of C 60

  5. Comparison of active and passive methods for radon exhalation from a high-exposure building material

    International Nuclear Information System (INIS)

    Abbasi, A.; Mirekhtiary, F.

    2013-01-01

    The radon exhalation rates and radon concentrations in granite stones used in Iran were measured by means of a high-resolution high purity Germanium gamma-spectroscopy system (passive method) and an AlphaGUARD model PQ 2000 (active method). For standard rooms (4.0 x 35.0 m area x 32.8 height) where ground and walls have been covered by granite stones, the radon concentration and the radon exhalation rate by two methods were calculated. The activity concentrations of 226 Ra in the selected granite samples ranged from 3.8 to 94.2 Bq kg -1 . The radon exhalation rate from the calculation of the 226 Ra activity concentration was obtained. The radon exhalation rates were 1.31-7.86 Bq m -2 h -1 . The direction measurements using an AlphaGUARD were from 218 to 1306 Bq m -3 with a mean of 625 Bq m -3 . Also, the exhalation rates measured by the passive and active methods were compared and the results of this study were the same, with the active method being 22% higher than the passive method. (authors)

  6. The effect of synchronized running activity with chronic stress on passive avoidance learning and body weight in rats

    Directory of Open Access Journals (Sweden)

    Maryam Radahmadi

    2013-01-01

    Results: Our results showed that: (1 Exercise under no stress provides beneficial effects on memory acquisition and retention time compared to Control group; especially retention time had significantly (P < 0.05 increased in exercised group. (2 Chronic stress with and without synchronized exercise significantly (P < 0.01, P < 0.05, respectively impaired acquisition and retention time. (3 Body weight differences were significantly (P < 0.01, P < 0.001 and P < 0.001 lower than Control group in exercise, stress and synchronized exercise with stress groups, respectively. (4 Adverse effects of restraint stress (psychical stress were probably greater than physical activity effects on learning, memory and weight loss. Conclusions: The data confirmed that synchronized exercise with stress had not significantly protective role in improvement of passive avoidance acquisition and retention time; hence it did not significantly improve learning and memory deficit in stressed rats; whereas exercise alone could improve memory deficit in rats.

  7. Residual insufficiency of hematopoiesis after acute or chronic exposure to gamma radiation or neutrons

    International Nuclear Information System (INIS)

    Wangenheim, K.H. v.; Peterson, H.P.; Feinendegen, L.E.

    1983-01-01

    Recovery of the stem cell quality is possible after acute exposure to 500 rad γ radiation up to a period of 6 months. Beyond this data, a significant residual damage remains. The same applies to quantitative stem cell recovery. Chronic γ exposure leads to less radiation damage than acute exposure. After a total accumulation of 500 rad, the proliferation factors after chronic exposure were, on an average 20% higher than after acute radiation exposure. 6 MeV neutron exposure reduced the stem cell quality and stem cell count much more efficiently than γ exposure. The relative biological effect of neutrons is at least 2.5 times as high as the γ effect, both for the stem cell count and the stem cell quality. (orig.) [de

  8. Temperature modulates phototrophic periphyton response to chronic copper exposure

    International Nuclear Information System (INIS)

    Lambert, Anne Sophie; Dabrin, Aymeric; Morin, Soizic; Gahou, Josiane; Foulquier, Arnaud; Coquery, Marina; Pesce, Stéphane

    2016-01-01

    Streams located in vineyard areas are highly prone to metal pollution. In a context of global change, aquatic systems are generally subjected to multi-stress conditions due to multiple chemical and/or physical pressures. Among various environmental factors that modulate the ecological effects of toxicants, special attention should be paid to climate change, which is driving an increase in extreme climate events such as sharp temperature rises. In lotic ecosystems, periphyton ensures key ecological functions such as primary production and nutrient cycling. However, although the effects of metals on microbial communities are relatively well known, there is scant data on possible interactions between temperature increase and metal pollution. Here we led a study to evaluate the influence of temperature on the response of phototrophic periphyton to copper (Cu) exposure. Winter communities, collected in a 8 °C river water, were subjected for six weeks to four thermal conditions in microcosms in presence or not of Cu (nominal concentration of 15 μg L"−"1). At the initial river temperature (8 °C), our results confirmed the chronic impact of Cu on periphyton, both in terms of structure (biomass, distribution of algal groups, diatomic composition) and function (photosynthetic efficiency). At higher temperatures (13, 18 and 23 °C), Cu effects were modulated. Indeed, temperature increase reduced Cu effects on algal biomass, algal class proportions, diatom assemblage composition and photosynthetic efficiency. This reduction of Cu effects on periphyton may be related to lower bioaccumulation of Cu and/or to selection of more Cu-tolerant species at higher temperatures. - Highlights: • At in situ temperature, Cu impacted structure and activity of phototrophic biofilms. • Cu effects were reduced with increasing temperature (from +5 °C to +15 °C). • The decrease in Cu effects may be related to lower Cu bioaccumulation in biofilms. • Changes in diatom

  9. Occupational exposure and risk of chronic obstructive pulmonary disease: a systematic review and meta-analysis.

    Science.gov (United States)

    Alif, Sheikh M; Dharmage, Shyamali C; Bowatte, Gayan; Karahalios, Amalia; Benke, Geza; Dennekamp, Martine; Mehta, Amar J; Miedinger, David; Künzli, Nino; Probst-Hensch, Nicole; Matheson, Melanie C

    2016-08-01

    Due to contradictory literature we have performed a systematic review and meta-analyse of population-based studies that have used Job Exposure Matrices to assess occupational exposure and risk of Chronic Obstructive Pulmonary Disease (COPD). Two researchers independently searched databases for published articles using predefined inclusion criteria. Study quality was assessed, and results pooled for COPD and chronic bronchitis for exposure to biological dust, mineral dust, and gases/fumes using a fixed and random effect model. Five studies met predetermined inclusion criteria. The meta-analysis showed low exposure to mineral dust, and high exposure to gases/fumes were associated with an increased risk of COPD. We also found significantly increased the risk of chronic bronchitis for low and high exposure to biological dust and mineral dust. Expert commentary: The relationship between occupational exposure assessed by the JEM and the risk of COPD and chronic bronchitis shows significant association with occupational exposure. However, the heterogeneity of the meta-analyses suggests more wide population-based studies with older age groups and longitudinal phenotype assessment of COPD to clarify the role of occupational exposure to COPD risk.

  10. Reproductive impairment in the zebrafish, Danio rerio, upon chronic exposure to 1,2,3-trichlorobenzene.

    NARCIS (Netherlands)

    Roex, E.W.M.; Giovannangelo, M.E.C.A.; van Gestel, C.A.M.

    2001-01-01

    Most organic pollutants are supposed to act via the mechanism of nonpolar narcosis upon acute exposure. Because the chronic effects of these compounds are still relatively unknown, in this study a chronic toxicity experiment was performed with zebrafish, Danio rerio, exposed to 1, 2,

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  13. Can Massive but Passive Exposure to Faces Contribute to Face Recognition Abilities?

    Science.gov (United States)

    Yovel, Galit; Halsband, Keren; Pelleg, Michel; Farkash, Naomi; Gal, Bracha; Goshen-Gottstein, Yonatan

    2012-01-01

    Recent studies have suggested that individuation of other-race faces is more crucial for enhancing recognition performance than exposure that involves categorization of these faces to an identity-irrelevant criterion. These findings were primarily based on laboratory training protocols that dissociated exposure and individuation by using…

  14. Effects of prenatal exposure to chronic mild stress and toluene in rats

    DEFF Research Database (Denmark)

    Hougaard, K. S.; Andersen, Maud Bering; Hansen, A. M.

    2005-01-01

    The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated in fe...

  15. Ocular effects of chronic exposure to welding light on calabar welders

    African Journals Online (AJOL)

    It was generally observed that welders in Calabar, Nigeria did not always wear their protective goggles during welding. Since chronic exposure to welding light can impair vision this study was done to assess the effect of exposure to welding light on ocular function of welders in Calabar, Nigeria. There were 195 subjects ...

  16. ASSESSMENT OF CHLORPYRIFOS EXPOSURE BY PASSIVE DOSIMETRY AND BIOMONITORING IN PESTICIDE WORKERS

    Science.gov (United States)

    Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the U.S. Environmental Protection Agency (EPA) has the authority to regulate the use of pesticides to prevent unreasonable adverse human health effects associated with pesticide exposure. Accordingly, the EPA...

  17. Smoking habits, exposure to passive smoking and attitudes to a non-smoking policy among hospital staff.

    Science.gov (United States)

    Zanetti, F; Gambi, A; Bergamaschi, A; Gentilini, F; De Luca, G; Monti, C; Stampi, S

    1998-01-01

    A survey was carried out into the smoking habits and exposure to passive smoking among health staff in the hospitals of Faenza, Forli and Rimini (Emilia-Romagna, Northern Italy), 2453 subjects answered anonymously a 41 question questionnaire. 53% of the subjects were professionals nurses, 16% doctors, 15% maintenance staff, 10% ancillary staff, 1% non-medical graduates, 2% were administrators and 3% were assigned to the category ¿other'. Of the subjects answering the questionnaire 39% were smokers, 19% ex-smokers and 42% non smokers. The highest number of smokers was found among women (41%) compared to men (37%) and among ancillary staff (48%) compared to nurses (41%) and doctors (31%). The males were mostly heavy smokers (> or = 20 cigarettes/d) and smoked strong cigarettes (> or = 12 mg/cig condensate content). The females were mostly light smokers (< 10 cigarettes/d) and smoked light cigarettes (1-6 mg/cig condensate content). A high percentage of subjects (87%) smoked at work especially in areas reserved for staff. 43% and 26% of shift workers and non-shift workers tended not to modify their habit when on morning or afternoon shifts. During night shifts the majority of them increased their tobacco consumption. Around 87% of hospital employees stated they were exposed to passive smoking inside the hospital especially in cooking areas, at information desks and corridors. Nurses, ancillaries and maintenance staff were those most exposed and for a greater number of hours per day compared to doctors. Almost all subjects were aware of the harm caused by passive smoking. 56% of smokers, 65% of ex-smokers and 72% of non smokers said they were willing to participate in future campaigns to limit smoking in their hospitals.

  18. Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

    OpenAIRE

    Balmes John; Eisner Mark D; Katz Patricia P; Trupin Laura; Yelin Edward H; Blanc Paul D

    2005-01-01

    Abstract Background Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Methods Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing...

  19. Using equilibrium passive dosing to maintain stable exposure concentrations of triclosan in a 6-week toxicity test

    DEFF Research Database (Denmark)

    Sobek, A.; Ribbenstedt, A.; Mustajärvi, L.

    2015-01-01

    toxicity tests. Yet, the European Commission’s criteria for chemicals’ risk assessments aim at protecting higher levels in the environment. To achieve protection of populations and ecosystems, reliable long-term ecotoxicologial tests are needed. In this study, we used equilibrium passive dosing to maintain...... stable exposure concentrations of triclosan (log Kow 4.8) in a 6-week multigeneration test with the benthic copepod Nitocra spinipes. The tests were performed in 10 mL vials casted with 1000 mg of silicone (DC 1-2577). Based on a previous pilot study, three triclosan concentrations were selected...... and tested (15 μg L-1; 30 μg L-1; 60 μg L-1) as well as a control (no triclosan). At test beginning, each vial contained 12 individuals consisting of 3 individuals from four different life stages. The test includes feeding with phytoplankton three times a week, which can lead to declining freely dissolved...

  20. Chronic exposure to organophosphate (OP) pesticides and neuropsychological functioning in farm workers: a review.

    Science.gov (United States)

    Muñoz-Quezada, María Teresa; Lucero, Boris Andrés; Iglesias, Verónica Paz; Muñoz, María Pía; Cornejo, Claudia Alejandra; Achu, Eduardo; Baumert, Brittney; Hanchey, Arianna; Concha, Carlos; Brito, Ana María; Villalobos, Marcos

    2016-01-01

    Previous studies have demonstrated that acute poisoning from exposure to organophosphate (OP) pesticides in agricultural workers causes adverse health effects. However, neuropsychological and cognitive effects of chronic occupational exposure to OP pesticides remain controversial. To identify, evaluate, and systematize existing evidence regarding chronic exposure to OP pesticides and neuropsychological effects in farmworkers. Using the PubMed search engine, a systematic review process was implemented and replicated according to the PRISMA statement. Eligibility criteria included workers over 18 years of age exposed to OP pesticides as well as assessment of neuropsychological and cognitive functioning. Search terms were in English and Spanish languages and included organophosphate and workers. Of the search results, 33 of 1,256 articles meet eligibility criteria. Twenty-four studies found an association between chronic occupational exposure to OP pesticides and low neuropsychological performance in workers. We classified nine of the studies to have study design limitations. Studies indicated occupational exposure to OP pesticides is linked to difficulties in executive functions, psychomotor speed, verbal, memory, attention, processing speed, visual-spatial functioning, and coordination. Nine studies find no relationship between OP pesticides exposure and neuropsychological performance. Overall, evidence suggests an association between chronic occupational exposure to OP pesticides and neuropsychological effects. However, there is no consensus about the specific cognitive skills affected.

  1. Occupational exposure to electromagnetic fields and chronic diseases

    OpenAIRE

    Håkansson, Niclas

    2003-01-01

    This thesis consider two exposures from the electromagnetic spectrum extremely low-frequency magnetic fields (ELF MF) and ultraviolet (UV) radiation. ELF MF are the lowest and UV radiation ranges among the highest frequencies of non-ionizing radiation. The exposure prevalence of these fields is high in the general population. Most people are exposed daily to either or both types and potential health effects are of great concern. The aim of the thesis was to study occupationa...

  2. Comparison of late effects of single x-ray exposure, chronic tritiated water ingestion, and chronic cesium-137 gamma exposure in mice

    International Nuclear Information System (INIS)

    Carsten, A.L.; Cronkite, E.P.

    1979-01-01

    There is concern over the possible late effects resulting from chronic exposure to tritiated water, a primary by-product of power reactors. We are comparing the genetic and somatic effects of tritiated water ingestion to acute x-ray or chronic cesium-137 gamma-ray exposures. Eight week old mice were maintaned on tritiated water in concentrations of 0.3, 1.0, and 3.0 μCi/ml. Identical animals received cesium-137 gamma exposures equivalent to that from the tritiated water. At 4 week intervals, animals were sacrificed and the hematopoietic stem cell content and cellularity of the bone marrow determined. For comparison of acute and chronic effects, one group of mice received a single whole-body x-ray exposure of 525 rads. The x-irradiated animals showed an immediate sharp decrease in marrow cellularity followed by gradual return to normal levels, with a lifelong reduction in number of marrow stem cells. Animals exposed to the two higher concentrations of tritiated water showed only slight reductions in marrow cellularity, with a lifelong reduction in hematopoietic stem cells in the bone marrow. Comparison of the external gamma exposures to chronic tritiated water ingestion indicates similar patterns. Maintenance of normal cellularity with a reduced number of stem cells in x-rayed animals was shown by tritiated thymidine cytocide to be due to the reduction in number of stem cells in the resting G/sub O/ stage. At this time it is not possible to determine whether there is a significant difference in relative biological effectiveness of tritiated water compared to cesium-137 gamma rays; however, indications are that they are similar

  3. Electrostatic Dust Cloth: A Passive Screening Method to Assess Occupational Exposure to Organic Dust in Bakeries

    Directory of Open Access Journals (Sweden)

    Carla Viegas

    2018-02-01

    Full Text Available Organic dust is widespread in the environment including occupational settings, such as bakeries. Recently, a new collection device—the electrostatic dust cloth (EDC—has been described for the assessment of occupational exposures. The aim of this study was to investigate the suitability of EDC for identifying the distribution patterns and exposure concentrations of particulate matter and microbial contaminants such as fungi and bacteria in bakeries. Twelve bakeries were selected, and dust was allowed to settle for 13 to 16 days on EDCs (a total of 33 samples. Particle counts and size distribution (0.3 µm, 0.5 µm, 1 µm, 2.5 µm, 5 µm and 10 µm were measured with direct-reading equipment. Higher EDC mass was significantly correlated (p values < 0.05 with higher fungal load on dichloran glycerol (DG18 and with particle size distribution in the 0.3 µm, 0.5 µm, 1.0 µm and 10.0 µm range. Fungal levels on malt extract agar (MEA ranged from 0 to 2886 CFU/m2 EDC in the warehouse setting, 0 to 500 CFU/m2 EDC in the production setting, and 0 to 3135 CFU/m2 EDC in the store. Penicillium sp. (42.56% was the most frequent fungi. Total bacterial load ranged from 0 to 18,859 CFU/m2 EDC in the warehouse, 0 to 71,656 CFU/m2 EDC in production, and 0 to 21,746 CFU/m2 EDC in the store. EDC assessment provided a longer-term integrated sample of organic dust, useful for identifying critical worksites in which particulate matter and bio-burden exposures are elevated. These findings suggest that EDC can be applied as a screening method for particulate matter-exposure assessment and as a complementary method to quantify exposures in occupational environments.

  4. Focus on Chronic Exposure for Deriving Drinking Water Guidance Underestimates Potential Risk to Infants

    Directory of Open Access Journals (Sweden)

    Helen Goeden

    2018-03-01

    Full Text Available In 2007, the Minnesota Department of Health (MDH developed new risk assessment methods for deriving human health-based water guidance (HBG that incorporated the assessment of multiple exposure durations and life stages. The methodology is based on US Environmental Protection Agency recommendations for protecting children’s health (US EPA 2002. Over the last 10 years, the MDH has derived multiple duration (e.g., short-term, subchronic, and chronic water guidance for over 60 chemicals. This effort involved derivation of multiple duration reference doses (RfDs and selection of corresponding water intake rates (e.g., infant, child, and lifetime. As expected, RfDs typically decreased with increasing exposure duration. However, the corresponding HBG frequently did not decrease with increasing duration. For more than half of the chemicals, the shorter duration HBG was lower than chronic HBG value. Conventional wisdom has been that chronic-based values will be the most conservative and will therefore be protective of less than chronic exposures. However, the MDH’s experience highlights the importance of evaluating short-term exposures. For many chemicals, elevated intake rates early in life, coupled with short-term RfDs, resulted in the lowest HBG. Drinking water criteria based on chronic assessments may not be protective of short-term exposures in highly exposed populations such as formula-fed infants.

  5. Cerebellar atrophy related to chronic exposure to toluene: case report

    Directory of Open Access Journals (Sweden)

    Benito Pereira Damasceno

    1994-03-01

    Full Text Available A 31-year-old woman presented slowly progressing ataxia and neurasthenic symptoms after 14-year occupational exposure to low concentration toluene vapour. Examination disclosed only cerebellar signs. Cognitive functions were normal except moderate visuo-spatial and constructive deficit CT imaging showed severe pancerebellar atrophy without pathological signs in other brain structures. Two years after she was removed from workplace, CT imaging and ataxia showed no worsening, while visuo-constructive function improved. The authors warn against possible neurotoxic risk associated with this kind of exposure.

  6. Association between lifetime exposure to passive smoking and risk of breast cancer subtypes defined by hormone receptor status among non-smoking Caucasian women.

    Directory of Open Access Journals (Sweden)

    Loreta Strumylaite

    Full Text Available Tobacco smoking is inconsistently associated with breast cancer. Although some studies suggest that breast cancer risk is related to passive smoking, little is known about the association with breast cancer by tumor hormone receptor status. We aimed to explore the association between lifetime passive smoking and risk of breast cancer subtypes defined by estrogen receptor and progesterone receptor status among non-smoking Caucasian women. A hospital-based case-control study was performed in 585 cases and 1170 controls aged 28-90 years. Information on lifetime passive smoking and other factors was collected via a self-administered questionnaire. Logistic regression was used for analyses restricted to the 449 cases and 930 controls who had never smoked actively. All statistical tests were two-sided. Adjusted odds ratio of breast cancer was 1.01 (95% confidence interval (CI: 0.72-1.41 in women who experienced exposure to passive smoking at work, 1.88 (95% CI: 1.38-2.55 in women who had exposure at home, and 2.80 (95% CI: 1.84-4.25 in women who were exposed at home and at work, all compared with never exposed regularly. Increased risk was associated with longer exposure: women exposed ≤ 20 years and > 20 years had 1.27 (95% CI: 0.97-1.66 and 2.64 (95% CI: 1.87-3.74 times higher risk of breast cancer compared with never exposed (Ptrend 0.05. There was evidence of interaction between passive smoking intensity and menopausal status in both overall group (P = 0.02 and hormone receptor-positive breast cancer group (P < 0.05. In Caucasian women, lifetime exposure to passive smoking is associated with the risk of breast cancer independent of tumor hormone receptor status with the strongest association in postmenopausal women.

  7. Effect of Chronic Dietary Copper Exposure on Haematology and ...

    African Journals Online (AJOL)

    Michael Horsfall

    ... of common carp and establish a threshold for dietary copper toxicity in the ... temperature 27.4 ± 0.420C and left unfed in the first 2 .... dependent effects of dietary copper exposure on .... mechanisms of acclimation to metals in freshwater fish.

  8. Computational estimation of decline in sweating in the elderly from measured body temperatures and sweating for passive heat exposure

    International Nuclear Information System (INIS)

    Hirata, Akimasa; Nomura, Tomoki; Laakso, Ilkka

    2012-01-01

    Several studies reported the difference in heat tolerance between younger and older adults, which may be attributable to the decline in the sweating rate. One of the studies suggested a hypothesis that the dominant factor causing the decline in sweating was the decline in thermal sensitivity due to a weaker signal from the periphery to the regulatory centres. However, no quantitative investigation of the skin temperature threshold for activating the sweating has been conducted in previous studies. In this study, we developed a computational code to simulate the time evolution of the temperature variation and sweating in realistic human models under heat exposure, in part by comparing the computational results with measured data from younger and older adults. Based on our computational results, the difference in the threshold temperatures for activating the thermophysiological response, especially for sweating, is examined between older and younger adults. The threshold for activating sweating in older individuals was found to be about 1.5 °C higher than that in younger individuals. However, our computation did not suggest that it was possible to evaluate the central alteration with ageing by comparing the computation with the measurements for passive heat exposure, since the sweating rate is marginally affected by core temperature elevation at least for the scenarios considered here. The computational technique developed herein is useful for understanding the thermophysiological response of older individuals from measured data. (note)

  9. Chronic Toxic Metal Exposure and Cardiovascular Disease: Mechanisms of Risk and Emerging Role of Chelation Therapy.

    Science.gov (United States)

    Aneni, Ehimen C; Escolar, Esteban; Lamas, Gervasio A

    2016-12-01

    Over the last few decades, there has been a growing body of epidemiologic evidence linking chronic toxic metal exposure to cardiovascular disease-related morbidity and mortality. The recent and unexpectedly positive findings from a randomized, double-blind, multicenter trial of metal chelation for the secondary prevention of atherosclerotic cardiovascular disease (Trial to Assess Chelation Therapy (TACT)) have focused the discussion on the role of chronic exposure to toxic metals in the development and propagation of cardiovascular disease and the role of toxic metal chelation therapy in the secondary prevention of cardiovascular disease. This review summarizes the most recent evidence linking chronic toxic metal exposure to cardiovascular disease and examines the findings of TACT.

  10. Particulate matter air pollution exposure: role in the development and exacerbation of chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Sean H Ling

    2009-06-01

    Full Text Available Sean H Ling, Stephan F van EedenJames Hogg iCAPTURE Centre for Pulmonary and Cardiovascular Research and Heart and Lung Institute, University of British Columbia, Vancouver, British Columbia, CanadaAbstract: Due to the rapid urbanization of the world population, a better understanding of the detrimental effects of exposure to urban air pollution on chronic lung disease is necessary. Strong epidemiological evidence suggests that exposure to particulate matter (PM air pollution causes exacerbations of pre-existing lung conditions, such as, chronic obstructive pulmonary disease (COPD resulting in increased morbidity and mortality. However, little is known whether a chronic, low-grade exposure to ambient PM can cause the development and progression of COPD. The deposition of PM in the respiratory tract depends predominantly on the size of the particles, with larger particles deposited in the upper and larger airways and smaller particles penetrating deep into the alveolar spaces. Ineffective clearance of this PM from the airways could cause particle retention in lung tissues, resulting in a chronic, low-grade inflammatory response that may be pathogenetically important in both the exacerbation, as well as, the progression of lung disease. This review focuses on the adverse effects of exposure to ambient PM air pollution on the exacerbation, progression, and development of COPD.Keywords: chronic obstructive pulmonary disease, particulate matter, air pollution, alveolar macrophage

  11. Chronic Exposure to Subtherapeutic Antibiotics Aggravates Ischemic Stroke Outcome in Mice

    Directory of Open Access Journals (Sweden)

    Xiao-Hui Dong

    2017-10-01

    Full Text Available Subtherapeutic antibiotics have been widely used in agriculture since the 1950s, which can be accumulated in human body through various approaches and may have long-term consequences. However, there is limited information about the link between chronic subtherapeutic antibiotic exposure and the outcome of ischemic brain injury. Here we showed that long-term treatment with subtherapeutic chlortetracycline, penicillin or vancomycin, which were widely used in agriculture approved by US Food and Drug Administration (FDA, could impair EPC functions, reduce ischemic brain angiogenesis and aggravate cerebral ischemic injury and long-term stroke outcomes in mice. In addition, transplantated EPCs from chronic antibiotic-treated mice showed a lower therapeutic effect on cerebral ischemic injury reduction and local angiogenesis promotion compared to those from control mice, and EPCs from the donor animals could integrate into the recipient ischemic brain in mice. Furthermore, transplanted EPCs might exert paracrine effects on cerebral ischemic injury reduction in mice, which could be impaired by chronic antibiotic exposure. In conclusion, chronic subtherapeutic antibiotic exposure aggravated cerebral ischemic injury in mice, which might be partly attributed to the impairment of both EPC-mediated angiogenesis and EPCs' paracrine effects. These findings reveal a previously unrecognized impact of chronic subtherapeutic antibiotic exposure on ischemic injury.

  12. Occupational exposures and chronic obstructive pulmonary disease (COPD): comparison of a COPD-specific job exposure matrix and expert-evaluated occupational exposures.

    Science.gov (United States)

    Kurth, Laura; Doney, Brent; Weinmann, Sheila

    2017-03-01

    To compare the occupational exposure levels assigned by our National Institute for Occupational Safety and Health chronic obstructive pulmonary disease-specific job exposure matrix (NIOSH COPD JEM) and by expert evaluation of detailed occupational information for various jobs held by members of an integrated health plan in the Northwest USA. We analysed data from a prior study examining COPD and occupational exposures. Jobs were assigned exposure levels using 2 methods: (1) the COPD JEM and (2) expert evaluation. Agreement (Cohen's κ coefficients), sensitivity and specificity were calculated to compare exposure levels assigned by the 2 methods for 8 exposure categories. κ indicated slight to moderate agreement (0.19-0.51) between the 2 methods and was highest for organic dust and overall exposure. Sensitivity of the matrix ranged from 33.9% to 68.5% and was highest for sensitisers, diesel exhaust and overall exposure. Specificity ranged from 74.7% to 97.1% and was highest for fumes, organic dust and mineral dust. This COPD JEM was compared with exposures assigned by experts and offers a generalisable approach to assigning occupational exposure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  13. Cytogenetic studies in workers with chronic occupational radiation exposure

    International Nuclear Information System (INIS)

    Grynszpan, D.

    1989-01-01

    The technique of chromosomal aberration detection on peripheral lymphocytes blood samples from monazite industry workers was used to study the cytogenetic effect of low chronic radiation doses. Cells from 51 workers and 21 controls were analysed. Cytogenetic data from individuals from different working areas were statistically compared among themselves and with the control group. The possible correlations between chromosomal aberration frequencies and cumulative external dose and working time were investigated. The influence of smoking was also tested. The link to the wives spontaneous abortions was analysed. Our results indicate possible biological effects on this sample of workers. (author)

  14. Chronic ethanol exposure inhibits distraction osteogenesis in a mouse model: Role of the TNF signaling axis

    International Nuclear Information System (INIS)

    Wahl, Elizabeth C.; Aronson, James; Liu, Lichu; Liu, Zhendong; Perrien, Daniel S.; Skinner, Robert A.; Badger, Thomas M.; Ronis, Martin J.J.; Lumpkin, Charles K.

    2007-01-01

    Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine that modulates osteoblastogenesis. In addition, the demonstrated inhibitory effects of chronic ethanol exposure on direct bone formation in rats are hypothetically mediated by TNF-α signaling. The effects in mice are unreported. Therefore, we hypothesized that in mice (1) administration of a soluble TNF receptor 1 derivative (sTNF-R1) would protect direct bone formation during chronic ethanol exposure, and (2) administration of recombinant mouse TNF-α (rmTNF-α) to ethanol naive mice would inhibit direct bone formation. We utilized a unique model of limb lengthening (distraction osteogenesis, DO) combined with liquid diets to measure chronic ethanol's effects on direct bone formation. Chronic ethanol exposure resulted in increased marrow TNF, IL-1, and CYP 2E1 RNA levels in ethanol-treated vs. control mice, while no significant weight differences were noted. Systemic administration of sTNF-R1 during DO (8.0 mg/kg/2 days) to chronic ethanol-exposed mice resulted in enhanced direct bone formation as measured radiologically and histologically. Systemic rmTNF-α (10 μg/kg/day) administration decreased direct bone formation measures, while no significant weight differences were noted. We conclude that chronic ethanol-associated inhibition of direct bone formation is mediated to a significant extent by the TNF signaling axis in a mouse model

  15. Early changes of lymphocyte RNA and serum immunoglobulins following chronic exposure to benzene

    Energy Technology Data Exchange (ETDEWEB)

    Chircu, V.; Ionescu, M.; Zgoan

    Hematologic and immunochemical investigations carried out in 270 workers with chronic exposure to benzene demonstrated changes of the nucleologram and of the area of lymphocyte nucleoli as well as disorders of the humoral immune response revealed by radial immunodiffusion. The numerical rise of bi- and polynucleolated cells, of cells with irregular macronucleoli as well as an enlargement of the nucleolar area are assumed to reflect an increase of the endolymphocytic amounts of RNA. An increased capacity of immunoglobulin formation, particularly of IgM, was also observed. All these changes are considered as early signs of an enhanced immune reactivity following chronic exposure to benzene.

  16. Influence of chronic x-ray exposure on adrenal glucocorticoid function and adrenocorticocyte membrane potential

    International Nuclear Information System (INIS)

    Gorban', Je.M.; Topol'nikova, N.V.

    1998-01-01

    The peculiarities of adrenal glucocorticoid function and membrane potential (MP) of zona fasciculata adrenocorticocyte (ACC) in rats after chronic x-ray exposure was studied. The changes of adrenal glucocorticoid function caused by chronic x-ray exposure within a relatively small period of irradiation (1.5 months) are obscure and manifest themselves only at physiological load. With the prolongation of the period (8 and 15 months), more considerable inhibition of the adrenal glucocorticoid function and disturbances in the membrane mechanisms of ACC MP level regulation are revealed

  17. Impairment induced by chronic occupational cadmium exposure during brazing process

    International Nuclear Information System (INIS)

    Anwar, S.M.; Aly, M.M.

    2002-01-01

    Cadmium (CD) is considered a metal of the 20 th century to which all inhabitants of develop societies are exposed. Long-term occupational and environmental exposure to CD often results in renal dysfunction as the kidney is considered the critical target organ. The aim of this work was to evalutate both resporatory and renal manifestations induced by occupational exposure to CD compounds during brazing process, and suggesting a protocol for prevention and control for CD- induced health effects. This study was conducted on 20 males occupationally exposed workers. They are divided into two groups: Group-1 included (10) exposed smokers and group-2 included (10) exposed non-smokers. Results of both groups were compared with those of 10 healthy age and sex matched non-smokers. All subjects were subjected to detailed history taking and laboratory investigations including blood and urinary CD, liver profile (SGOT, SGPT and alkline phosphates), kindey function tests (blood urea, creatinine and urinary beta 2 - microglobulin). The level of Cd in the atmosphere of the work plase air was also assessed to detect the degree of exposure as it was about 6 times greater than thesave level (1 mu /m 3 ). (1) This study demonstrated elevation levels of blood CD, urea, creatinine and urinary CD and beta 2 -microglobulin for both exposed worker groups than the controls. In additions no appreciable were noted for liver function tests, although the levels fell within normal range

  18. Effects of prenatal exposure to chronic mild stress and toluene in rats

    DEFF Research Database (Denmark)

    Hougaard, Karin; Andersen, Maibritt B; Hansen, Ase M

    2005-01-01

    The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated...... in female offspring of pregnant rats (Mol:WIST) exposed to chronic mild stress (CMS) during gestational days (GD) 9-20, or 1500 ppm toluene, 6 h/day during gestational days 7-20, or a combination of the two. Prenatal CMS was associated with decreased thymic weight and increased auditory startle response....... The corticosterone response to restraint seemed modified by prenatal exposure to toluene. Lactational body weight was decreased in offsprings subjected to CMS, primarily due to effects in the combined exposure group. Cognitive function was investigated in the Morris water maze, and some indications of improved...

  19. Segmental hair testing to disclose chronic exposure to psychoactive drugs.

    Science.gov (United States)

    Marchei, Emilia; Palmi, Ilaria; Pichini, Simona; Pacifici, Roberta; Anton Airaldi, Ileana-Rita; Costa Orvay, Juan Antonio; García Serra, Joan; Bonet Serra, Bartolomé; García-Algar, Óscar

    2016-06-15

    This study presents the case of a 4-year-old healthy child admitted to the paediatric ward for suspected accidental intoxication due to ingestion of narcoleptic drugs (methylphenidate, sertraline and quetiapine), taken on a regular basis by his 8-year-old brother affected by Asperger syndrome.Intoxication can be objectively assessed by measurements of drugs and metabolites in biological matrices with short-term (blood and urine) or long-term (hair) detection windows. At the hospital, the child's blood and urine were analysed by immunoassay (confirmed by liquid chromatography-mass spectrometry), and sertraline and quetiapine and their metabolites were identified. The suspicion that the mother administered drugs chronically prompted the analysis of six, consecutive 2-cm segments of the child's hair, using ultra-high performance liquid chromatography-tandem mass spectrometry, thereby accounting for ingestion over the previous 12 months. Quetiapine was found in the first four segments with a mean concentration of 1.00 ng/mg ± 0.94 ng/mg hair while sertraline and its metabolite, desmethyl-sertraline, were found in all segments with a mean concentration of 2.65 ± 0.94 ng/mg and 1.50 ± 0.94 ng/mg hair, respectively. Hair analyses were negative for methylphenidate and its metabolite (ritalinic acid). Biological matrices testing for psychoactive drugs disclosed both acute and chronic intoxication with quetiapine and sertraline administered by the mother.

  20. Cigarettes vs. e-cigarettes: Passive exposure at home measured by means of airborne marker and biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Ballbè, Montse [Tobacco Control Unit, Cancer Prevention and Control Program, Institut Català d' Oncologia, L’Hospitalet de Llobregat, Barcelona (Spain); Catalan Network of Smoke-free Hospitals, L' Hospitalet de Llobregat, Barcelona (Spain); Cancer Prevention and Control Group, Institut d' Investigació Biomèdica de Bellvitge – IDIBELL, L’Hospitalet de Llobregat, Barcelona (Spain); Addictions Unit, Institute of Neurosciences, Hospital Clínic de Barcelona – IDIBAPS, Barcelona (Spain); Department of Clinical Sciences, Universitat de Barcelona, Barcelona (Spain); Martínez-Sánchez, Jose M., E-mail: jmmartinez@iconcologia.net [Tobacco Control Unit, Cancer Prevention and Control Program, Institut Català d' Oncologia, L’Hospitalet de Llobregat, Barcelona (Spain); Cancer Prevention and Control Group, Institut d' Investigació Biomèdica de Bellvitge – IDIBELL, L’Hospitalet de Llobregat, Barcelona (Spain); Biostatistics Unit, Department of Basic Sciences, Universitat Internacional de Catalunya, Sant Cugat del Vallès, Barcelona (Spain); Sureda, Xisca; Fu, Marcela [Tobacco Control Unit, Cancer Prevention and Control Program, Institut Català d' Oncologia, L’Hospitalet de Llobregat, Barcelona (Spain); Cancer Prevention and Control Group, Institut d' Investigació Biomèdica de Bellvitge – IDIBELL, L’Hospitalet de Llobregat, Barcelona (Spain); Department of Clinical Sciences, Universitat de Barcelona, Barcelona (Spain); and others

    2014-11-15

    Background: There is scarce evidence about passive exposure to the vapour released or exhaled from electronic cigarettes (e-cigarettes) under real conditions. The aim of this study is to characterise passive exposure to nicotine from e-cigarettes' vapour and conventional cigarettes' smoke at home among non-smokers under real-use conditions. Methods: We conducted an observational study with 54 non-smoker volunteers from different homes: 25 living at home with conventional smokers, 5 living with nicotine e-cigarette users, and 24 from control homes (not using conventional cigarettes neither e-cigarettes). We measured airborne nicotine at home and biomarkers (cotinine in saliva and urine). We calculated geometric mean (GM) and geometric standard deviations (GSD). We also performed ANOVA and Student's t tests for the log-transformed data. We used Bonferroni-corrected t-tests to control the family error rate for multiple comparisons at 5%. Results: The GMs of airborne nicotine were 0.74 μg/m{sup 3} (GSD=4.05) in the smokers’ homes, 0.13 μg/m{sup 3} (GSD=2.4) in the e-cigarettes users’ homes, and 0.02 μg/m{sup 3} (GSD=3.51) in the control homes. The GMs of salivary cotinine were 0.38 ng/ml (GSD=2.34) in the smokers’ homes, 0.19 ng/ml (GSD=2.17) in the e-cigarettes users’ homes, and 0.07 ng/ml (GSD=1.79) in the control homes. Salivary cotinine concentrations of the non-smokers exposed to e-cigarette's vapour at home (all exposed ≥2 h/day) were statistically significant different that those found in non-smokers exposed to second-hand smoke ≥2 h/day and in non-smokers from control homes. Conclusions: The airborne markers were statistically higher in conventional cigarette homes than in e-cigarettes homes (5.7 times higher). However, concentrations of both biomarkers among non-smokers exposed to conventional cigarettes and e-cigarettes’ vapour were statistically similar (only 2 and 1.4 times higher, respectively). The levels of airborne

  1. Cigarettes vs. e-cigarettes: Passive exposure at home measured by means of airborne marker and biomarkers

    International Nuclear Information System (INIS)

    Ballbè, Montse; Martínez-Sánchez, Jose M.; Sureda, Xisca; Fu, Marcela

    2014-01-01

    Background: There is scarce evidence about passive exposure to the vapour released or exhaled from electronic cigarettes (e-cigarettes) under real conditions. The aim of this study is to characterise passive exposure to nicotine from e-cigarettes' vapour and conventional cigarettes' smoke at home among non-smokers under real-use conditions. Methods: We conducted an observational study with 54 non-smoker volunteers from different homes: 25 living at home with conventional smokers, 5 living with nicotine e-cigarette users, and 24 from control homes (not using conventional cigarettes neither e-cigarettes). We measured airborne nicotine at home and biomarkers (cotinine in saliva and urine). We calculated geometric mean (GM) and geometric standard deviations (GSD). We also performed ANOVA and Student's t tests for the log-transformed data. We used Bonferroni-corrected t-tests to control the family error rate for multiple comparisons at 5%. Results: The GMs of airborne nicotine were 0.74 μg/m 3 (GSD=4.05) in the smokers’ homes, 0.13 μg/m 3 (GSD=2.4) in the e-cigarettes users’ homes, and 0.02 μg/m 3 (GSD=3.51) in the control homes. The GMs of salivary cotinine were 0.38 ng/ml (GSD=2.34) in the smokers’ homes, 0.19 ng/ml (GSD=2.17) in the e-cigarettes users’ homes, and 0.07 ng/ml (GSD=1.79) in the control homes. Salivary cotinine concentrations of the non-smokers exposed to e-cigarette's vapour at home (all exposed ≥2 h/day) were statistically significant different that those found in non-smokers exposed to second-hand smoke ≥2 h/day and in non-smokers from control homes. Conclusions: The airborne markers were statistically higher in conventional cigarette homes than in e-cigarettes homes (5.7 times higher). However, concentrations of both biomarkers among non-smokers exposed to conventional cigarettes and e-cigarettes’ vapour were statistically similar (only 2 and 1.4 times higher, respectively). The levels of airborne nicotine and

  2. Chronic obstructive pulmonary disease and long-term exposure to traffic-related air pollution: a cohort study

    DEFF Research Database (Denmark)

    Andersen, Zorana J; Hvidberg, Martin; Jensen, Steen S

    2011-01-01

    Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood.......Short-term exposure to air pollution has been associated with exacerbation of chronic obstructive pulmonary disease (COPD), whereas the role of long-term exposures on the development of COPD is not yet fully understood....

  3. The Effects of Passive Cigarette Smoke Exposure on the Survival of the Reverse Sural Fasciocutaneous Flap.

    Science.gov (United States)

    Sadagatullah, Abdul Nawfar; Halim, Ahmad Sukari; Bathusha, Mohd Shakir; Ramachandran, Anantha Kumar

    2017-12-01

    Background  The possibility of a person who had undergone surgery to be exposed to the ill effects of cigarette smoke is high, more so if the person lives with a smoker. With increasing popularity of reverse sural fasciocutaneous flaps, a surgeon may have to manage a person who lives with a smoker or is exposed to cigarette smoke. A clear understanding of the effects of exposure to cigarette smoke on reverse sural fasciocutaneous flaps is necessary. This study was performed to establish a clearer understanding of the effects of smoking on reverse sural fasciocutaneous flaps and evidence for preoperative patient counseling about smoking and smoke exposure. Objective  The study investigated effects of exposure to cigarette smoke on the survival of the reverse sural fasciocutaneous flap. Methods  This was an experimental observational study conducted at the Laboratory for Animal Research Unit in the Health Campus of Universiti Sains Malaysia. Twelve adult White New Zealand rabbits ( Oryctolagus cuniculus ) were divided into two groups of six. All 12 rabbits had a 2.5- × 2.5-cm reverse sural fasciocutaneous flap raised on both its hind limbs. The group exposed to cigarette smoke underwent 4 weeks of smoke exposure for 2 hours daily prior to surgery. This was then continued until analysis of the results. The control group had no intervention. All flaps were analyzed on the seventh postoperative day, after tracing on transparent plastic sheets with the necrotic area marked followed by 2D planimetry done on a grid paper. The flaps were assessed on the total flap area and survival area percentage. It was recorded as mean ± SD. The presence or absence of infection and hematoma was also noted. Results  Twelve flaps were analyzed in each group. Total mean flap area and survival area percentage of the control group were 120.33 ± 31.03 mm 2 and 80.12 ± 15.75%, respectively, whereas in the cigarette smoke-exposed group, it was 121.83 ± 17.93 mm 2

  4. Passive exposure to electronic cigarette (e-cigarette) use increases desire for combustible and e-cigarettes in young adult smokers.

    Science.gov (United States)

    King, Andrea C; Smith, Lia J; McNamara, Patrick J; Matthews, Alicia K; Fridberg, Daniel J

    2015-09-01

    Passive exposure to combustible cigarette use has been shown to act as a cue to increase smoking urge. Given the resemblance of e-cigarettes and other electronic nicotine delivery systems (ENDS) to combustible cigarettes, we examined whether these devices could also act as a cue to increase smoking desire and urges in those passively exposed. Young adult daily smokers (age 18-35 years; N=60) completed subjective ratings before and after exposure to a study confederate drinking bottled water (control cue) and then smoking either a combustible or e-cigarette (active cue). Smoking desire and urge ratings were measured with visual analogue scale items for desire for a regular and an e-cigarette and the Brief Questionnaire of Smoking Urges. Passive exposure to both the e-cigarette and combustible cigarette cue significantly increased observers' ratings of desire and urge to smoke a regular cigarette (all ps<0.05). Exposure to the e-cigarette cue but not the regular cigarette cue also increased desire to smoke an e-cigarette (p<0.01). The results provide the first evidence in a controlled setting that electronic cigarette exposure may evoke smoking urges in young adult daily smokers. With replication, these findings may have relevance for ENDS regulation and policy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. Chronic intermittent ethanol exposure in early adolescent and adult male rats: effects on tolerance, social behavior, and ethanol intake.

    Science.gov (United States)

    Broadwater, Margaret; Varlinskaya, Elena I; Spear, Linda P

    2011-08-01

    Given the prevalence of alcohol use in adolescence, it is important to understand the consequences of chronic ethanol exposure during this critical period in development. The purpose of this study was to assess possible age-related differences in susceptibility to tolerance development to ethanol-induced sedation and withdrawal-related anxiety, as well as voluntary ethanol intake after chronic exposure to relatively high doses of ethanol during adolescence or adulthood. Juvenile/adolescent and adult male Sprague-Dawley rats were assigned to one of five 10-day exposure conditions: chronic ethanol (4 g/kg every 48 hours), chronic saline (equivalent volume every 24 hours), chronic saline/acutely challenged with ethanol (4 g/kg on day 10), nonmanipulated/acutely challenged with ethanol (4 g/kg on day 10), or nonmanipulated. For assessment of tolerance development, duration of the loss of righting reflex (LORR) and blood ethanol concentrations (BECs) upon regaining of righting reflex (RORR) were tested on the first and last ethanol exposure days in the chronic ethanol group, with both saline and nonmanipulated animals likewise challenged on the last exposure day. Withdrawal-induced anxiety was indexed in a social interaction test 24 hours after the last ethanol exposure, with ethanol-naïve chronic saline and nonmanipulated animals serving as controls. Voluntary intake was assessed 48 hours after the chronic exposure period in chronic ethanol, chronic saline and nonmanipulated animals using an 8-day 2 bottle choice, limited-access ethanol intake procedure. In general, adolescent animals showed shorter durations of LORR and higher BECs upon RORR than adults on the first and last ethanol exposure days, regardless of chronic exposure condition. Adults, but not adolescents, developed chronic tolerance to the sedative effects of ethanol, tolerance that appeared to be metabolic in nature. Social deficits were observed after chronic ethanol in both adolescents and adults

  6. Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Balmes John

    2005-05-01

    Full Text Available Abstract Background Exposure to environmental tobacco smoke (ETS, which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Methods Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. Results Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21. The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84. The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. Conclusion ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure.

  7. 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.

    Science.gov (United States)

    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)

  8. Chronic exposure to low frequency noise at moderate levels causes impaired balance in mice.

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    Haruka Tamura

    Full Text Available We are routinely exposed to low frequency noise (LFN; below 0.5 kHz at moderate levels of 60-70 dB sound pressure level (SPL generated from various sources in occupational and daily environments. LFN has been reported to affect balance in humans. However, there is limited information about the influence of chronic exposure to LFN at moderate levels for balance. In this study, we investigated whether chronic exposure to LFN at a moderate level of 70 dB SPL affects the vestibule, which is one of the organs responsible for balance in mice. Wild-type ICR mice were exposed for 1 month to LFN (0.1 kHz and high frequency noise (HFN; 16 kHz at 70 dB SPL at a distance of approximately 10-20 cm. Behavior analyses including rotarod, beam-crossing and footprint analyses showed impairments of balance in LFN-exposed mice but not in non-exposed mice or HFN-exposed mice. Immunohistochemical analysis showed a decreased number of vestibular hair cells and increased levels of oxidative stress in LFN-exposed mice compared to those in non-exposed mice. Our results suggest that chronic exposure to LFN at moderate levels causes impaired balance involving morphological impairments of the vestibule with enhanced levels of oxidative stress. Thus, the results of this study indicate the importance of considering the risk of chronic exposure to LFN at a moderate level for imbalance.

  9. Chronic 14-day exposure to insecticides or methylmercury modulates neuronal activity in primary rat cortical cultures

    NARCIS (Netherlands)

    Dingemans, Milou; Schütte, Marijke G; Wiersma, Daphne M M; de Groot, Aart; van Kleef, Gina; Wijnolts, Fiona; Westerink, Remco

    2016-01-01

    There is an increasing demand for in vitro test systems to detect neurotoxicity for use in chemical risk assessment. In this study, we evaluated the applicability of rat primary cortical cultures grown on multi-well micro-electrode arrays (mwMEAs) to detect effects of chronic 14-day exposure to

  10. Prolonged Exposure Treatment of Chronic PTSD in Juvenile Sex Offenders: Promising Results from Two Case Studies

    Science.gov (United States)

    Hunter, John A.

    2010-01-01

    Prolonged exposure (PE) was used to treat chronic PTSD secondary to severe developmental trauma in two adolescent male sex offenders referred for residential sex offender treatment. Both youth were treatment resistant prior to initiation of PE and showed evidence of long-standing irritability and depression/anxiety. Clinical observation and…

  11. Chronic radiation exposure as an ecological factor: Hypermethylation and genetic differentiation in irradiated Scots pine populations

    International Nuclear Information System (INIS)

    Volkova, P.Yu.; Geras'kin, S.A.; Horemans, N.; Makarenko, E.S.; Saenen, E.; Duarte, G.T.; Nauts, R.; Bondarenko, V.S.; Jacobs, G.; Voorspoels, S.; Kudin, M.

    2018-01-01

    Genetic and epigenetic changes were investigated in chronically irradiated Scots pine (Pinus sylvestris L.) populations from territories that were heavily contaminated by radionuclides as result of the Chernobyl Nuclear Power Plant accident. In comparison to the reference site, the genetic diversity revealed by electrophoretic mobility of AFLPs was found to be significantly higher at the radioactively contaminated areas. In addition, the genome of pine trees was significantly hypermethylated at 4 of the 7 affected sites. - Highlights: • Chronic radiation exposure changes the genetic structure of plant populations. • Genomes of irradiated pines are hypermethylated. • The level of hypermethylation does not depend on annual dose. - These results indicate that even relatively low levels of chronic radiation exposure can influence on the genetic characteristics and the methylation status of natural pine populations and that it should be considered as an important ecological factor reflecting the anthropogenic impact on ecosystems.

  12. No effect of low-level chronic neonicotinoid exposure on bumblebee learning and fecundity

    Directory of Open Access Journals (Sweden)

    Saija Piiroinen

    2016-03-01

    Full Text Available In recent years, many pollinators have declined in abundance and diversity worldwide, presenting a potential threat to agricultural productivity, biodiversity and the functioning of natural ecosystems. One of the most debated factors proposed to be contributing to pollinator declines is exposure to pesticides, particularly neonicotinoids, a widely used class of systemic insecticide. Also, newly emerging parasites and diseases, thought to be spread via contact with managed honeybees, may pose threats to other pollinators such as bumblebees. Compared to honeybees, bumblebees could be particularly vulnerable to the effects of stressors due to their smaller and more short-lived colonies. Here, we studied the effect of field-realistic, chronic clothianidin exposure and inoculation with the parasite Nosema ceranae on survival, fecundity, sugar water collection and learning using queenless Bombus terrestris audax microcolonies in the laboratory. Chronic exposure to 1 ppb clothianidin had no significant effects on the traits studied. Interestingly, pesticide exposure in combination with additional stress caused by harnessing bees for Proboscis Extension Response (PER learning assays, led to an increase in mortality. In contrast to previous findings, the bees did not become infected by N. ceranae after experimental inoculation with the parasite spores, suggesting variability in host resistance or parasite virulence. However, this treatment induced a slight, short-term reduction in sugar water collection, potentially through stimulation of the immune system of the bees. Our results suggest that chronic exposure to 1 ppb clothianidin does not have adverse effects on bumblebee fecundity or learning ability.

  13. Pesticide exposures and chronic kidney disease of unknown etiology: an epidemiologic review.

    Science.gov (United States)

    Valcke, Mathieu; Levasseur, Marie-Eve; Soares da Silva, Agnes; Wesseling, Catharina

    2017-05-23

    The main causes of chronic kidney disease (CKD) globally are diabetes and hypertension but epidemics of chronic kidney disease of unknown etiology (CKDu) occur in Central America, Sri Lanka, India and beyond. Althoug also being observed in women, CKDu concentrates among men in agricultural sectors. Therefore, suspicions fell initially on pesticide exposure, but currently chronic heat stress and dehydration are considered key etiologic factors. Responding to persistent community and scientific concerns about the role of pesticides, we performed a systematic review of epidemiologic studies that addressed associations between any indicator of pesticide exposure and any outcome measure of CKD. Of the 21 analytical studies we identified, seven were categorized as with low, ten with medium and four with relatively high explanation value. Thirteen (62%) studies reported one or more positive associations, but four had a low explanation value and three presented equivocal results. The main limitations of both positive and negative studies were unspecific and unquantified exposure measurement ('pesticides'), the cross-sectional nature of most studies, confounding and selection bias. The four studies with stronger designs and better exposure assessment (from Sri Lanka, India and USA) all showed exposure-responses or clear associations, but for different pesticides in each study, and three of these studies were conducted in areas without CKDu epidemics. No study investigated interactions between pesticides and other concommittant exposures in agricultural occupations, in particular heat stress and dehydration. In conclusion, existing studies provide scarce evidence for an association between pesticides and regional CKDu epidemics but, given the poor pesticide exposure assessment in the majority, a role of nephrotoxic agrochemicals cannot be conclusively discarded. Future research should procure assessment of lifetime exposures to relevant specific pesticides and enough power

  14. The Role of Musk in Relieving the Neurodegenerative Changes Induced After Exposure to Chronic Stress.

    Science.gov (United States)

    Abd El Wahab, Manal Galal; Ali, Soad Shaker; Ayuob, Nasra Naeim

    2018-06-01

    This study aimed to evaluate the effect induced by musk on Alzheimer's disease-such as neurodegenerative changes in mice exposed to chronic unpredictable mild stress (CUMS). Forty male Swiss albino mice were divided into 4 groups (n = 10); control, CUMS, CUMS + fluoxetine, CUMS + musk. At the end of the experiment, behavior of the mice was assessed. Serum corticosterone level, hippocampal protein level of the glucocorticoid receptors, and brain-derived neurotropic factor were also assessed. Hippocampus was histopathologically examined. Musk improved depressive status induced after exposure to CUMS as evidenced by the forced swimming and open field tests and improved the short-term memory as evidenced by the elevated plus maze test. Musk reduced both corticosterone levels and the hippocampal neurodegenerative changes observed after exposure to CUMS. These improvements were comparable to those induced by fluoxetine. Musk alleviated the memory impairment and neurodegenerative changes induced after exposure to the chronic stress.

  15. Injury of the blood-testies barrier after low-dose-rate chronic radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Young Hoon; Bae Min Ji; Lee, Chang Geun; Yang, Kwang Mo; Jur, Kyu; Kim, Jong Sun [Dongnam Institute of Radiological and Medical Science, Busan (Korea, Republic of)

    2014-04-15

    The systemic effect of radiation increases in proportionally with the dose and dose rate. Little is known concerning the relationships between harmful effects and accumulated dose, which is derived from continuous low-dose rate radiation exposure. Recent our studies show that low-dose-rate chronic radiation exposure (3.49 mGy/h) causes adverse effects in the testis at a dose of 2 Gy (6 mGy/h). However, the mechanism of the low-dose-rate 2 Gy irradiation induced testicular injury remains unclear. The present results indicate that low-dose rate chronic radiation might affect the BTB permeability, possibly by decreasing levels of ZO-1, Occludin-1, and NPC-2. Furthermore, our results suggest that there is a risk of male infertility through BTB impairment even with low-dose-rate radiation if exposure is continuous.

  16. Association between pre- and perinatal exposures and Tourette syndrome or chronic tic disorder in the ALSPAC cohort.

    Science.gov (United States)

    Mathews, Carol A; Scharf, Jeremiah M; Miller, Laura L; Macdonald-Wallis, Corrie; Lawlor, Debbie A; Ben-Shlomo, Yoav

    2014-01-01

    Tourette syndrome and chronic tic disorder are heritable but aetiologically complex. Although environment plays a role in their development, existing studies of non-genetic risk factors are inconsistent. To examine the association between pre- and perinatal exposures and Tourette syndrome/chronic tic disorder in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective longitudinal pre-birth cohort. Relationships between exposures and Tourette syndrome/chronic tic disorder were examined in 6090 children using logistic regression. Maternal alcohol and cannabis use, inadequate maternal weight gain and parity were associated with Tourette syndrome or Tourette syndrome/chronic tic disorder. Other previously reported exposures, including birth weight and prenatal maternal smoking, were not associated with Tourette syndrome/chronic tic disorder. This study supports previously reported relationships between Tourette syndrome/chronic tic disorder and prenatal alcohol exposure, and identifies additional previously unexplored potential prenatal risk factors.

  17. Association between pre- and perinatal exposures and Tourette syndrome or chronic tic disorder in the ALSPAC cohort†

    Science.gov (United States)

    Mathews, Carol A.; Scharf, Jeremiah M.; Miller, Laura L.; Macdonald-Wallis, Corrie; Lawlor, Debbie A.; Ben-Shlomo, Yoav

    2014-01-01

    Background Tourette syndrome and chronic tic disorder are heritable but aetiologically complex. Although environment plays a role in their development, existing studies of non-genetic risk factors are inconsistent. Aims To examine the association between pre- and perinatal exposures and Tourette syndrome/chronic tic disorder in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective longitudinal pre-birth cohort. Method Relationships between exposures and Tourette syndrome/chronic tic disorder were examined in 6090 children using logistic regression. Results Maternal alcohol and cannabis use, inadequate maternal weight gain and parity were associated with Tourette syndrome or Tourette syndrome/chronic tic disorder. Other previously reported exposures, including birth weight and prenatal maternal smoking, were not associated with Tourette syndrome/chronic tic disorder. Conclusions This study supports previously reported relationships between Tourette syndrome/chronic tic disorder and prenatal alcohol exposure, and identifies additional previously unexplored potential prenatal risk factors. PMID:24262815

  18. Inflammation mediators in employees in chronic exposure to neurotoxicants

    Directory of Open Access Journals (Sweden)

    Galina Bodienkova

    2014-08-01

    Full Text Available Objectives: The aim of this work is to perform comparative estimation of cytokines levels in chlorinated hydrocarbons and metallic mercury exposure in employees in the dynamics of neurologic disorders formation. Material and Methods: The contents of cytokines IL-1β, IL-2, IL-4, IL-6, TNF-α, INF-γ were determined in blood sera using the method of hardphasic immunoferment analysis. The significance of different average values was assessed using the parametric and non-parametric criteria - Student (in normal distribution and Mann-Whitney tests taking into account the Bonferonni correction (non-difference from normal distribution. Results: It was shown that, a number of inflammation mediators with the dominance, depending on the expositional toxicant and expression of neurological deficiency, take part in the neurointoxication development. Healthy employees show pro-inflammatory responses with different expression degree, which dominate in the immune regulation processes regardless of the expositional factors (metallic mercury vapors and chlorinated hydrocarbons. Conclusions: The production intensity and interconnection between the pro- and anti-inflammatory cytokines may change in the occupational injuries of the nervous system development process. The decrease in the serum concentrations of cytokines along with the increase of clinical manifestation severity may prove dysregulation of the immune system, which promotes maintaining of pathological process and progradient process of neurointoxication. The most obvious is the imbalance of cytokines in the employees exposed to metallic mercury (in all the examined groups that increases neurointoxication in the distant period.

  19. Chronic prenatal lead exposure impairs long-term memory in day old chicks.

    Science.gov (United States)

    Zhong, Zhaoming; Zhang, Chunxiao; Rizak, Joshua D; Cui, Yonghua; Xu, Shiqing; Che, Yi

    2010-05-26

    Environmental exposure to lead during developmental stages has been established as a potential cause of intellectual deficits. The high susceptibility of rapidly developing fetal and infant brains to external factors suggests that impairment of later cognitive functions may arise from relatively minor prenatal exposure to environmental lead levels. In this study, we used the one-trial passive avoidance learning paradigm with day old chicks to evaluate memory function and memory consolidation in response to prenatal lead exposure. Lead acetate (5.5mg/kg, 11mg/kg, 16.5mg/kg) was administered daily from E9 to E16 via direct injection into the airspace in chick eggs. Higher doses of lead acetate (11mg/kg, 16.5mg/kg) administration had significant effects on the hatching success (23.4 and 17, respectively) and hatch weight ( approximately 10% decrease) of chicks when compared to equivalent treatments of sodium acetate (11mg/kg, 16.5mg/kg) (plong-term memory after 120min following training in the one-trial passive avoidance learning task (pmemory processes. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

    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

  1. Glucose administration attenuates spatial memory deficits induced by chronic low-power-density microwave exposure.

    Science.gov (United States)

    Lu, Yonghui; Xu, Shangcheng; He, Mindi; Chen, Chunhai; Zhang, Lei; Liu, Chuan; Chu, Fang; Yu, Zhengping; Zhou, Zhou; Zhong, Min

    2012-07-16

    Extensive evidence indicates that glucose administration attenuates memory deficits in rodents and humans, and cognitive impairment has been associated with reduced glucose metabolism and uptake in certain brain regions including the hippocampus. In the present study, we investigated whether glucose treatment attenuated memory deficits caused by chronic low-power-density microwave (MW) exposure, and the effect of MW exposure on hippocampal glucose uptake. We exposed Wistar rats to 2.45 GHz pulsed MW irradiation at a power density of 1 mW/cm(2) for 3 h/day, for up to 30 days. MW exposure induced spatial learning and memory impairments in rats. Hippocampal glucose uptake was also reduced by MW exposure in the absence or presence of insulin, but the levels of blood glucose and insulin were not affected. However, these spatial memory deficits were reversed by systemic glucose treatment. Our results indicate that glucose administration attenuates the spatial memory deficits induced by chronic low-power-density MW exposure, and reduced hippocampal glucose uptake may be associated with cognitive impairment caused by MW exposure. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Bilateral Vestibular Dysfunction Associated With Chronic Exposure to Military Jet Propellant Type-Eight Jet Fuel

    Directory of Open Access Journals (Sweden)

    Terry D. Fife

    2018-05-01

    Full Text Available We describe three patients diagnosed with bilateral vestibular dysfunction associated with the jet propellant type-eight (JP-8 fuel exposure. Chronic exposure to aromatic and aliphatic hydrocarbons, which are the main constituents of JP-8 military aircraft jet fuel, occurred over 3–5 years’ duration while working on or near the flight line. Exposure to toxic hydrocarbons was substantiated by the presence of JP-8 metabolite n-hexane in the blood of one of the cases. The presenting symptoms were dizziness, headache, fatigue, and imbalance. Rotational chair testing confirmed bilateral vestibular dysfunction in all the three patients. Vestibular function improved over time once the exposure was removed. Bilateral vestibular dysfunction has been associated with hydrocarbon exposure in humans, but only recently has emphasis been placed specifically on the detrimental effects of JP-8 jet fuel and its numerous hydrocarbon constituents. Data are limited on the mechanism of JP-8-induced vestibular dysfunction or ototoxicity. Early recognition of JP-8 toxicity risk, cessation of exposure, and customized vestibular therapy offer the best chance for improved balance. Bilateral vestibular impairment is under-recognized in those chronically exposed to all forms of jet fuel.

  3. DNA methylation and histone deacetylation regulating insulin sensitivity due to chronic cold exposure.

    Science.gov (United States)

    Wang, Xiaoqing; Wang, Lai; Sun, Yizheng; Li, Ruiping; Deng, Jinbo; Deng, Jiexin

    2017-02-01

    In this study, we investigated the causal relationship between chronic cold exposure and insulin resistance and the mechanisms of how DNA methylation and histone deacetylation regulate cold-reduced insulin resistance. 46 adult male mice from postnatal day 90-180 were randomly assigned to control group and cold-exposure group. Mice in cold-exposure group were placed at temperature from -1 to 4 °C for 30 days to mimic chronic cold environment. Then, fasting blood glucose, blood insulin level and insulin resistance index were measured with enzymatic methods. Immunofluorescent labeling was carried out to visualize the insulin receptor substrate 2 (IRS2), Obese receptor (Ob-R, a leptin receptor), voltage-dependent anion channel protein 1 (VDAC1), cytochrome C (cytC), 5-methylcytosine (5-mC) positive cells in hippocampal CA1 area. Furthermore, the expressions of some proteins mentioned above were detected with Western blot. The results showed: ① Chronic cold exposure could reduce the insulin resistance index (P cold-exposure group than in control group with both immunohistochemical staining and Western blot (P cold exposure increased DNA methylation and histone deacetylation in the pyramidal cells of CA1 area and led to an increase in the expression of histone deacetylase 1 (HDAC1) and DNA methylation relative enzymes (P cold exposure can improve insulin sensitivity, with the involvement of DNA methylation, histone deacetylation and the regulation of mitochondrial energy metabolism. These epigenetic modifications probably form the basic mechanism of cold-reduced insulin resistance. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Heavy metal uranium affects the brain cholinergic system in rat following sub-chronic and chronic exposure

    International Nuclear Information System (INIS)

    Bensoussan, Helene; Grancolas, Line; Dhieux-Lestaevel, Bernadette; Delissen, Olivia; Vacher, Claire-Marie; Dublineau, Isabelle; Voisin, Philippe; Gourmelon, Patrick; Taouis, Mohammed; Lestaevel, Philippe

    2009-01-01

    Uranium is a heavy metal naturally present in the environment that may be chronically ingested by the population. Previous studies have shown that uranium is present in the brain and alters behaviour, notably locomotor activity, sensorimotor ability, sleep/wake cycle and the memory process, but also metabolism of neurotransmitters. The cholinergic system mediates many cognitive systems, including those disturbed after chronic exposure to uranium i.e., spatial memory, sleep/wake cycle and locomotor activity. The objective of this study was to assess whether these disorders follow uranium-induced alteration of the cholinergic system. In comparison with 40 control rats, 40 rats drank 40 mg/L uranyl nitrate for 1.5 or 9 months. Cortex and hippocampus were removed and gene expression and protein level were analysed to determine potential changes in cholinergic receptors and acetylcholine levels. The expression of genes showed various alterations in the two brain areas after short- and long-term exposure. Nevertheless, protein levels of the choline acetyltransferase enzyme (ChAT), the vesicular transporter of acetylcholine (VAChT) and the nicotinic receptor β2 sub-unit (nAChRβ2) were unmodified in all cases of the experiment and muscarinic receptor type 1 (m1AChR) protein level was disturbed only after 9 months of exposure in the cortex (-30%). Acetylcholine levels were unchanged in the hippocampus after 1.5 and 9 months, but were decreased in the cortex after 1.5 months only (-22%). Acetylcholinesterase (AChE) activity was also unchanged in the hippocampus but decreased in the cortex after 1.5 and 9 months (-16% and -18%, respectively). Taken together, these data indicate that the cholinergic system is a target of uranium exposure in a structure-dependent and time-dependent manner. These cholinergic alterations could participate in behavioural impairments.

  5. Hair analysis following chronic smoked-drugs-of-abuse exposure in adults and their toddler: a case report

    OpenAIRE

    Papaseit, Esther; Joya, Xavier; Velasco, Marta; Civit, Ester; Mota, Pau; Bertran, Marta; Vall, Oriol; Garcia-Algar, Oscar

    2011-01-01

    Abstract Introduction Over the past two decades, the study of chronic cocaine and crack cocaine exposure in the pediatric population has been focused on the potential adverse effects, especially in the prenatal period and early childhood. Non-invasive biological matrices have become an essential tool for the assessment of a long-term history of drug of abuse exposure. Case report We analyze the significance of different biomarker values in hair after chronic crack exposure in a two-year-old C...

  6. The Neurological Significance of Abnormal Natural Killer Cell Activity in Chronic Toxigenic Mold Exposures

    Directory of Open Access Journals (Sweden)

    Ebere Anyanwu

    2003-01-01

    Full Text Available Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological significance of abnormal natural killer cell (NKC activity in chronic toxigenic mold exposure. A comprehensive review of the literature was carried out to evaluate and assess the conditions under which the immune system could be dysfunctionally interfered with leading to abnormal NKC activity and the involvement of mycotoxins in these processes. The functions, mechanism, the factors that influence NKC activities, and the roles of mycotoxins in NKCs were cited wherever necessary. The major presentations are headache, general debilitating pains, nose bleeding, fevers with body temperatures up to 40�C (104�F, cough, memory loss, depression, mood swings, sleep disturbances, anxiety, chronic fatigue, vertigo/dizziness, and in some cases, seizures. Although sleep is commonly considered a restorative process that is important for the proper functioning of the immune system, it could be disturbed by mycotoxins. Most likely, mycotoxins exert some rigorous effects on the circadian rhythmic processes resulting in sleep deprivation to which an acute and transient increase in NKC activity is observed. Depression, psychological stress, tissue injuries, malignancies, carcinogenesis, chronic fatigue syndrome, and experimental allergic encephalomyelitis could be induced at very low physiological concentrations by mycotoxin-induced NKC activity. In the light of this review, it is concluded that chronic exposures to toxigenic mold could lead to abnormal NKC activity with a wide

  7. Analysis of chronic radiation exposure at small doses

    International Nuclear Information System (INIS)

    Krestinina, L.Y.

    2000-01-01

    The purpose of the study was to analyze the late effects of radiation exposure among residents of settlements located on the territory of the East-Urals Radiation Trace (EURT) in the Southern Urals. In 1957 an explosion occurred at the depot of radioactive waste in the Southern Urals. An area of 23000 km 2 was contaminated, with contamination density of over 0.1 Ci/m 2 for 90 Sr. There were 217 populated ares on that territory with total population about 270000. The residents of 22 villages with contamination density of over 4 Ci/km 2 for 90 Sr were evacuated. The times of evacuation differed from 7 to 670 days since the accident, depending on the level of contamination. In 1988-1993 an individualized registry was created at the Urals Research Center for Radiation Medicine (URCRM) which included information on the residents of 22 evacuated villages and a proportion of unevacuated residents of the EURT area. Currently, the registry contains data on 30000 residents. Of that number 17000 persons were born before, and 12000 after the accident (including about 9000 offspring of exposed residents evacuated from the EURT, and about 3000 persons who were born after the accident and have been living permanently in the EURT area). Over the 35-year period since the accident the residents have received mean effective doses ranging from 23 to 530 mSv. The mean effective doses received by permanent residents range from 5 to 60 mSv. The cohort of people exposed on the EURT territory was identified based on the information contained in the registry. If a person happened to be in the EURT area at the time of the accident, he/she was considered to be eligible for inclusion in the cohort. Over the 35-year period (from 1957 through 1992) 29.5% of 17872 residents died, and 35% of the original cohort were lost to follow-up for different reasons. To enable an analysis a control group was established which included residents of villages located outside, but close enough, to the EURT area

  8. Reaction of fresh water zooplankton community to chronic radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Osipov, D.; Pryakhin, E. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation); Ivanov, I. [FSUE Mayak PA (Russian Federation)

    2014-07-01

    The characteristic features of ecological community as a whole and cenosis of zooplankton organisms as part of it determine the intensity of the processes of self-purification of water and the formation of a particular body of water. Identifying features of the structure and composition of the zooplankton community of aquatic ecosystems exposed to different levels of radiation exposure, it is necessary to identify patterns of changes in zooplankton and hydro-biocenosis as a whole. Industrial reservoirs, the storage of liquid low-level radioactive waste 'Mayak' for decades, have high radiation load. A large range of levels of radioactive contamination (total volume beta-activity in water varies from 2.2x10{sup 3} to 2.3x10{sup 7} Bq/l, total volume alpha-activity - from 2.6x10{sup -1} to 3.1x10{sup 3} Bq/l) provides a unique opportunity to study ecosystems in a number of reservoirs with increasing impact of radiation factor. We studied five reservoirs that were used as the storage of low-and intermediate-level liquid radioactive waste pond and one comparison water body. In parallel with zooplankton sampling water samples were collected for hydro-chemical analysis. 41 indicators were analysed in order to assess the water chemistry. To determine the content of radionuclides in the various components of the ecosystem samples were collected from water, bottom sediments and plankton. Sampling of zooplankton for the quantitative analysis was performed using the method of weighted average auto bathometer. Apshteyn's plankton net of the surface horizon was used for qualitative analysis of the species composition of zooplankton. Software package ERICA Assessment Tool 2012 was used for the calculation of the absorbed dose rate. Species diversity and biomass of zooplankton, the share of rotifers in the number of species, abundance and biomass decrease with the increase of the absorbed dose rate and salinity. The number of species in a sample decreases with the

  9. Investigation of rare chronic lipoid pneumonia associated with occupational exposure to paraffin aerosol.

    Science.gov (United States)

    Han, Chenghong; Liu, Lihai; Du, Shiping; Mei, Jianhua; Huang, Ling; Chen, Min; Lei, Yongliang; Qian, Junwen; Luo, Jianyong; Zhang, Meibian

    2016-09-30

    Occupational exposure to paraffin is an infrequent cause of lipoid pneumonia (LP) and related data are scare. We investigated the possible relationship between three rare cases of chronic LP and occupational exposure to paraffin aerosol in an iron foundry. The three cases of LP and their workplaces were investigated using data from field investigations, air monitoring, pulmonary radiological examinations, cell staining, and lung biopsies. The patients had long-term occupational exposure to paraffin. X-ray diffraction testing revealed that the raw material from the workshop was paraffin crystal. The air concentrations of paraffin aerosol in workplaces were significantly higher than outdoor background levels. Small diffuse and miliary shadows with unclear edges were observed throughout the whole lungs via radiography. Computed tomography revealed diffuse punctate nodules and a high density of stripe-like shadows in both lungs (ground-glass opacity in a lower lobe, and a mass-like lesion and high translucent area near the bottom of the lung). Lipid-laden macrophages were found in the sputum and bronchial lavage. A broadened alveolar septum and local focal fibrosis were also discovered via lung biopsy. The inflammatory reaction in the lung tissues appeared to resolve over time. These three rare cases of chronic LP in workers during molding and repair processes were associated with occupational paraffin aerosol exposure. Therefore, primary prevention is essential for molding or repairing workers in the iron foundry, and a differential diagnosis of occupational chronic LP (vs. pneumoconiosis) should be considered when treating these workers.

  10. Mitochondrial ROS induced by chronic ethanol exposure promote hyper-activation of the NLRP3 inflammasome

    Directory of Open Access Journals (Sweden)

    Laura R. Hoyt

    2017-08-01

    Full Text Available Alcohol use disorders are common both in the United States and globally, and are associated with a variety of co-morbid, inflammation-linked diseases. The pathogenesis of many of these ailments are driven by the activation of the NLRP3 inflammasome, a multi-protein intracellular pattern recognition receptor complex that facilitates the cleavage and secretion of the pro-inflammatory cytokines IL-1β and IL-18. We hypothesized that protracted exposure of leukocytes to ethanol would amplify inflammasome activation, which would help to implicate mechanisms involved in diseases associated with both alcoholism and aberrant NLRP3 inflammasome activation. Here we show that long-term ethanol exposure of human peripheral blood mononuclear cells and a mouse macrophage cell line (J774 amplifies IL-1β secretion following stimulation with NLRP3 agonists, but not with AIM2 or NLRP1b agonists. The augmented NRLP3 activation was mediated by increases in iNOS expression and NO production, in conjunction with increases in mitochondrial membrane depolarization, oxygen consumption rate, and ROS generation in J774 cells chronically exposed to ethanol (CE cells, effects that could be inhibited by the iNOS inhibitor SEITU, the NO scavenger carboxy-PTIO, and the mitochondrial ROS scavenger MitoQ. Chronic ethanol exposure did not alter K+ efflux or Zn2+ homeostasis in CE cells, although it did result in a lower intracellular concentration of NAD+. Prolonged administration of acetaldehyde, the product of alcohol dehydrogenase (ADH mediated metabolism of ethanol, mimicked chronic ethanol exposure, whereas ADH inhibition prevented ethanol-induced IL-1β hypersecretion. Together, these results indicate that increases in iNOS and mitochondrial ROS production are critical for chronic ethanol-induced IL-1β hypersecretion, and that protracted exposure to the products of ethanol metabolism are probable mediators of NLRP3 inflammasome hyperactivation. Keywords: Inflammasome, IL

  11. A safe strategy to decrease fetal lead exposure in a woman with chronic intoxication.

    Science.gov (United States)

    Leiba, Adi; Hu, Howard; Zheng, Amin; Kales, Stefanos N

    2010-08-01

    During pregnancy skeletal lead is mobilized by maternal bone turnover and can threaten fetal development. The exact strategy suggested to women of childbearing age, who were chronically exposed to lead, and, thus, have high bone lead burden, is not well established. We describe 4 years of follow-up of a 29-year-old woman with chronic lead intoxication. We (a) advised her to delay conception until 'toxicological clearance', (b) treated her with multiple courses of lead chelator, DMSA, and (c) prescribed oral calcium. Patient had low blood lead and protoporphyrin level during pregnancy until delivery. Delaying conception, lead chelation, and calcium supplementation can decrease fetal exposure.

  12. TOWARDS RELIABLE AND COST-EFFECTIVE OZONE EXPOSURE ASSESSMENT: PARAMETER EVALUATION AND MODEL VALIDATION USING THE HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    Accurate assessment of chronic human exposure to atmospheric criteria pollutants, such as ozone, is critical for understanding human health risks associated with living in environments with elevated ambient pollutant concentrations. In this study, we analyzed a data set from a...

  13. Perinatal exposure to genistein, a soy phytoestrogen, improves spatial learning and memory but impairs passive avoidance learning and memory in offspring.

    Science.gov (United States)

    Kohara, Yumi; Kuwahara, Rika; Kawaguchi, Shinichiro; Jojima, Takeshi; Yamashita, Kimihiro

    2014-05-10

    This study investigated the effects of perinatal genistein (GEN) exposure on the central nervous system of rat offspring. Pregnant dams orally received GEN (1 or 10 mg/kg/day) or vehicle (1 ml/kg/day) from gestation day 10 to postnatal day 14. In order to assess the effects of GEN on rat offspring, we used a battery of behavioral tests, including the open-field, elevated plus-maze, MAZE and step-through passive avoidance tests. MAZE test is an appetite-motivation test, and we used this mainly for assessing spatial learning and memory. In the MAZE test, GEN groups exhibited shorter latency from start to goal than the vehicle-treated group in both sexes. On the other hand, performances in the step-through passive avoidance test were non-monotonically inhibited by GEN in both sexes, and a significant difference was observed in low dose of the GEN-treated group compared to the vehicle-treated group in female rats. Furthermore, we found that perinatal exposure to GEN did not significantly alter locomotor activity or emotionality as assessed by the open-field and elevated-plus maze tests. These results suggest that perinatal exposure to GEN improved spatial learning and memory of rat offspring, but impaired their passive avoidance learning and memory. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. 38 CFR 3.316 - Claims based on chronic effects of exposure to mustard gas and Lewisite.

    Science.gov (United States)

    2010-07-01

    ... effects of exposure to mustard gas and Lewisite. 3.316 Section 3.316 Pensions, Bonuses, and Veterans... Compensation Ratings and Evaluations; Service Connection § 3.316 Claims based on chronic effects of exposure to mustard gas and Lewisite. (a) Except as provided in paragraph (b) of this section, exposure to the...

  15. Occupational exposures are associated with worse morbidity in patients with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Paulin, Laura M; Diette, Gregory B; Blanc, Paul D; Putcha, Nirupama; Eisner, Mark D; Kanner, Richard E; Belli, Andrew J; Christenson, Stephanie; Tashkin, Donald P; Han, MeiLan; Barr, R Graham; Hansel, Nadia N

    2015-03-01

    Links between occupational exposures and morbidity in individuals with established chronic obstructive pulmonary disease (COPD) remain unclear. To determine the impact of occupational exposures on COPD morbidity. A job exposure matrix (JEM) determined occupational exposure likelihood based on longest job in current/former smokers (n = 1,075) recruited as part of the Subpopulations and Intermediate Outcomes in COPD Study, of whom 721 had established COPD. Bivariate and multivariate linear regression models estimated the association of occupational exposure with COPD, and among those with established disease, the occupational exposure associations with 6-minute-walk distance (6MWD), the Modified Medical Research Council Dyspnea Scale (mMRC), the COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), 12-item Short-Form Physical Component (SF-12), and COPD exacerbations requiring health care utilization, adjusting for demographics, current smoking status, and cumulative pack-years. An intermediate/high risk of occupational exposure by JEM was found in 38% of participants. In multivariate analysis, those with job exposures had higher odds of COPD (odds ratio, 1.44; 95% confidence interval, 1.04-1.97). Among those with COPD, job exposures were associated with shorter 6MWDs (-26.0 m; P = 0.006); worse scores for mMRC (0.23; P = 0.004), CAT (1.8; P = 0.003), SGRQ (4.5; P = 0.003), and SF-12 Physical (-3.3; P Accounting for smoking, occupational exposure was associated with COPD risk and, for those with established disease, shorter walk distance, greater breathlessness, worse quality of life, and increased exacerbation risk. Clinicians should obtain occupational histories from patients with COPD because work-related exposures may influence disease burden.

  16. Non-smoking Chronic Obstructive Pulmonary Disease Attributed to Occupational Exposure to Silica Dust.

    Science.gov (United States)

    Tsuchiya, Kazuo; Toyoshima, Mikio; Kamiya, Yosuke; Nakamura, Yutaro; Baba, Satoshi; Suda, Takafumi

    2017-01-01

    An 85-year-old, never-smoking man presented with exertional dyspnea. He had been exposed to silica dust in the work place. Chest computed tomography revealed bronchial wall thickening without emphysema. A pulmonary function test showed airflow obstruction without impaired gas transfer. Airway hyperresponsiveness and reversibility were not evident. A transbronchial lung biopsy showed findings suggestive of mineral dust exposure, such as fibrosis and slight pigmentation of bronchioles. He was diagnosed with non-smoking chronic obstructive pulmonary disease (COPD) due to occupational exposure to silica dust. His symptoms were improved using an inhaled long-acting bronchodilator. The clinical characteristics of non-smoking COPD are discussed in this report.

  17. Hematological and biochemical effects of chronic CO exposure on the Japanese quail

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, J.J.; McGrath, J.J.

    1975-01-01

    Japanese Quail were exposed to a concentration of 300 to 350 ppm CO to maintain an equilibrium carboxyhemoglobin concentration of 30% for a period of 4 weeks. Compared to a control group of birds maintained in an identical chamber, the CO-exposed quail demonstrated increases in hematocrit ratio and hemoglobin concentration. At the end of the exposure period, the CO-exposed quail had significantly larger plasma glucose concentrations than the control birds. Cardiac and skeletal muscle carbohydrate stores were not affected by chronic CO exposure.

  18. Chronic ionizing radiation exposure as a tumor promoter in mouse skin

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Trivedi, A.

    1992-01-01

    We have tested a chronic exposure to 90 Y beta-radiation as a tumor promoter in mouse skin previously exposed to a chemical tumor initiator. Three different tests of radiation as a stage I tumor promoter, in skin subsequently given chemical stage II promotion, all indicated that the beta-radiation acted as a weak stage I skin tumor promoter. It showed no action as either a stage II or complete tumor promoter. (author)

  19. Chronic prenatal ethanol exposure increases adiposity and disrupts pancreatic morphology in adult guinea pig offspring

    OpenAIRE

    Dobson, C C; Mongillo, D L; Brien, D C; Stepita, R; Poklewska-Koziell, M; Winterborn, A; Holloway, A C; Brien, J F; Reynolds, J N

    2012-01-01

    Background: Ethanol consumption during pregnancy can lead to a range of adverse developmental outcomes in children, termed fetal alcohol spectrum disorder (FASD). Central nervous system injury is a debilitating and widely studied manifestation of chronic prenatal ethanol exposure (CPEE). However, CPEE can also cause structural and functional deficits in metabolic pathways in offspring. Objectives and Methods: This study tested the hypothesis that CPEE increases whole-body adiposity and disrup...

  20. Chronic low dose radiation exposure and oxidative stress in radiation workers

    International Nuclear Information System (INIS)

    Ali, S.S.; Bhatt, M.B.; Kulkarni, MM.; Rajan, R.; Singh, B.B.; Venkataraman, G.

    1996-01-01

    Free radicals have been implicated in the pathogenesis of several human diseases. In this study free radical stress due to low dose chronic radiation exposures of radiation workers was examined as a possible atherogenic risk factor. Data on lipid profiles, lipid peroxidation and reduced glutathione content in blood indicated an absence of correlation with radiation doses up to 125 mSv. (author). 13 refs., 1 fig

  1. Using plutonium excretion data to predict dose from chronic and acute exposures

    International Nuclear Information System (INIS)

    Krahenbuhl, M.P.; Wilde, J.L.; Slaughter, D.M.

    2000-01-01

    Using fission track analysis (FTA) in conjunction with a composite theoretical model of the transport of plutonium (Pu) in the human body creates a new opportunity to estimate the exposure and dose to the general population due to plutonium in the environment. For the purposes of this study, data derived from FTA performed at the University of Utah's Center for Excellence in Nuclear Technology, Engineering and Research (CENTER) has been used to predict doses for two populations. Both population groups have no known history of plutonium exposures. Therefore, two exposure scenarios (acute and chronic) were assumed to provide boundaries for dose estimates. Dose predictions focus on equivalent dose to lung, liver, and skeletal systems and range from 0.01 mSv to 560 mSv as a function of organ, sample collection interval and exposure type. Additionally, these reconstructions demonstrate the sensitivity of dose calculations to time of sample collection and duration of exposure. As anticipated for a class Y particle, the predicted average equivalent tissue dose to the lungs represents the highest dose to the evaluated compartments. Furthermore, the data imply that the general population receives a dose one order of magnitude lower than a radiation worker with no history of exposure for the equivalent exposure scenario. (author)

  2. Mast Cells Limit the Exacerbation of Chronic Allergic Contact Dermatitis in Response to Repeated Allergen Exposure.

    Science.gov (United States)

    Gimenez-Rivera, Vladimir-Andrey; Siebenhaar, Frank; Zimmermann, Carolin; Siiskonen, Hanna; Metz, Martin; Maurer, Marcus

    2016-12-01

    Allergic contact dermatitis is a chronic T cell-driven inflammatory skin disease that is caused by repeated exposure to contact allergens. Based on murine studies of acute contact hypersensitivity, mast cells (MCs) are believed to play a role in its pathogenesis. The role of MCs in chronic allergic contact dermatitis has not been investigated, in part because of the lack of murine models for chronic contact hypersensitivity. We developed and used a chronic contact hypersensitivity model in wild-type and MC-deficient mice and assessed skin inflammatory responses to identify and characterize the role of MCs in chronic allergic contact dermatitis. Ear swelling chronic contact hypersensitivity responses increased markedly, up to 4-fold, in MC-deficient Kit W-sh/W-sh (Sash) and MCPT5-Cre + iDTR + mice compared with wild-type mice. Local engraftment with MCs protected Sash mice from exacerbated ear swelling after repeated oxazolone challenge. Chronic contact hypersensitivity skin of Sash mice exhibited elevated levels of IFN-γ, IL-17α, and IL-23, as well as increased accumulation of Ag-specific IFN-γ-producing CD8 + tissue-resident memory T (T RM ) cells. The CD8 + T cell mitogen IL-15, which was increased in oxazolone-challenged skin of Sash mice during the accumulation of cutaneous T RM cells, was efficiently degraded by MCs in vitro. MCs protect from the exacerbated allergic skin inflammation induced by repeated allergen challenge, at least in part, via effects on CD8 + T RM cells. MCs may notably influence the course of chronic allergic contact dermatitis. A better understanding of their role and the underlying mechanisms may lead to better approaches for the treatment of this common, disabling, and costly condition. Copyright © 2016 by The American Association of Immunologists, Inc.

  3. Acetaminophen induces xenobiotic-metabolizing enzymes in rat: Impact of a uranium chronic exposure.

    Science.gov (United States)

    Rouas, Caroline; Souidi, Maâmar; Grandcolas, Line; Grison, Stephane; Baudelin, Cedric; Gourmelon, Patrick; Pallardy, Marc; Gueguen, Yann

    2009-11-01

    The extensive use of uranium in civilian and military applications increases the risk of human chronic exposure. Uranium is a slightly radioactive heavy metal with a predominantly chemical toxicity, especially in kidney but also in liver. Few studies have previously shown some effects of uranium on xenobiotic-metabolizing enzymes (XME) that might disturb drug pharmacokinetic. The aim of this study was to determine whether a chronic (9 months) non-nephrotoxic low dose exposure to depleted uranium (DU, 1mg/rat/day) could modify the liver XME, using a single non-hepatotoxic acetaminophen (APAP) treatment (50mg/kg). Most of XME analysed were induced by APAP treatment at the gene expression level but at the protein level only CYP3A2 was significantly increased 3h after APAP treatment in DU-exposed rats whereas it remained at a basal level in unexposed rats. In conclusion, these results showed that a chronic non-nephrotoxic DU exposure specially modify CYP3A2 after a single therapeutic APAP treatment. Copyright © 2009 Elsevier B.V. All rights reserved.

  4. Incorporation and distribution of tritium in rats after chronic exposure to various tritiated compounds

    International Nuclear Information System (INIS)

    Takeda, H.

    1991-01-01

    Rats were chronically exposed to tritiated water ( 3 HHO) and several tritiated organic compounds ([ 3 H]leucine, [ 3 H]lysine, [ 3 H]glucose, [ 3 H]glucosamine, [ 3 H]thymidine and [ 3 H]uridine) dissolved in their drinking water. An analysis of tritium in wet and dry tissues of rats at the end of 22 days' chronic exposure showed that the chemical form of the ingested tritium was more important for tritium uptake in dry tissues than in wet tissues. The highest concentrations of OBT (organically bound tritium) were found in rats exposed to tritiated amino acids ([sup (3)/H]lysine and [ 3 H]leucine), 4-9 times higher than those in rats exposed to 3 HHO. The next highest concentrations were found in rats exposed to [ 3 H]uridine., The result of radiation dose estimations at the end of chronic exposure showed the contribution of OBT to total dose rate was higher in the tissues of rats exposed to tritiated organic compounds than that after exposure to 3 HHO. The differences between total dose rates from 3 HHO and those from tritiated organic compounds were within a factor of 2. (author)

  5. Developmental sub-chronic exposure to chlorpyrifos reduces anxiety-related behavior in zebrafish larvae

    Science.gov (United States)

    Richendrfer, Holly; Pelkowski, Sean D.; Colwill, Ruth M.; Créton, Robbert

    2013-01-01

    Neurobehavioral disorders such as anxiety, autism, and attention deficit hyperactivity disorders are typically influenced by genetic and environmental factors. Although several genetic risk factors have been identified in recent years, little is known about the environmental factors that either cause neurobehavioral disorders or contribute to their progression in genetically predisposed individuals. One environmental factor that has raised concerns is chlorpyrifos, an organophosphate pesticide that is widely used in agriculture and is found ubiquitously in the environment. In the present study, we examined the effects of sub-chronic chlorpyrifos exposure on anxiety-related behavior during development using zebrafish larvae. We found that sub-chronic exposure to 0.01 or 0.1 μM chlorpyrifos during development induces specific behavioral defects in 7-day-old zebrafish larvae. The larvae displayed decreases in swim speed and thigmotaxis, yet no changes in avoidance behavior were seen. Exposure to 0.001 μM chlorpyrifos did not affect swimming, thigmotaxis, or avoidance behavior and exposure to 1 μM chlorpyrifos induced behavioral defects, but also induced defects in larval morphology. Since thigmotaxis, a preference for the edge, is an anxiety-related behavior in zebrafish larvae, we propose that sub-chronic chlorpyrifos exposure interferes with the development of anxiety-related behaviors. The results of this study provide a good starting point for examination of the molecular, cellular, developmental, and neural mechanisms that are affected by environmentally relevant concentrations of organophosphate pesticides. A more detailed understanding of these mechanisms is important for the development of predictive models and refined health policies to prevent toxicant-induced neurobehavioral disorders. PMID:22579535

  6. Effects of chronic exposure to clothianidin on the earthworm Lumbricus terrestris.

    Science.gov (United States)

    Basley, Kate; Goulson, Dave

    2017-01-01

    Although neonicotinoids are targeted at insects, their predominant use as a seed dressing and their long persistence in soils mean that non-target soil organisms such as earthworms are likely to be chronically exposed to them. Chronic exposure may pose risks that are not evaluated in most toxicity tests. We experimentally tested the effect of field-realistic concentrations of a commonly used neonicotinoid, clothianidin, on mortality, weight gain, and food consumption to assess the impacts of chronic exposure over four months on fitness of L. terrestris individuals. We undertook three separate experiments, each with different exposure routes: treated soil only (experiment A), treated food and soil combined (experiment B) and treated food only (experiment C). Mortality was negatively affected by exposure from treated soil only with greatest mortality observed in the groups exposed to the two highest concentrations (20 ppb and 100 ppb), but no clear effect on mortality was found in the other two experiments. When clothianidin was present in the food, an anti-feedant effect was present in months one and two which subsequently disappeared; if this occurs in the field, it could result in reduced rates of decomposition of treated crop foliage. We found no significant effects of any treatment on worm body mass. We cannot rule out stronger adverse effects if worms come into close proximity to treated seeds, or if other aspects of fitness were examined. Overall, our data suggest that field-realistic exposure to clothianidin has a significant but temporary effect on food consumption and can have weak but significant impacts on mortality of L. terrestris.

  7. Effects of chronic exposure to clothianidin on the earthworm Lumbricus terrestris

    Directory of Open Access Journals (Sweden)

    Kate Basley

    2017-04-01

    Full Text Available Although neonicotinoids are targeted at insects, their predominant use as a seed dressing and their long persistence in soils mean that non-target soil organisms such as earthworms are likely to be chronically exposed to them. Chronic exposure may pose risks that are not evaluated in most toxicity tests. We experimentally tested the effect of field-realistic concentrations of a commonly used neonicotinoid, clothianidin, on mortality, weight gain, and food consumption to assess the impacts of chronic exposure over four months on fitness of L. terrestris individuals. We undertook three separate experiments, each with different exposure routes: treated soil only (experiment A, treated food and soil combined (experiment B and treated food only (experiment C. Mortality was negatively affected by exposure from treated soil only with greatest mortality observed in the groups exposed to the two highest concentrations (20 ppb and 100 ppb, but no clear effect on mortality was found in the other two experiments. When clothianidin was present in the food, an anti-feedant effect was present in months one and two which subsequently disappeared; if this occurs in the field, it could result in reduced rates of decomposition of treated crop foliage. We found no significant effects of any treatment on worm body mass. We cannot rule out stronger adverse effects if worms come into close proximity to treated seeds, or if other aspects of fitness were examined. Overall, our data suggest that field-realistic exposure to clothianidin has a significant but temporary effect on food consumption and can have weak but significant impacts on mortality of L. terrestris.

  8. Role of oxidative stress in liver and kidney in uranium toxicity after chronic exposure

    International Nuclear Information System (INIS)

    Poisson - Moreau-De-Lizoreux, C.

    2013-01-01

    Uranium is a radioactive heavy metal found in the environment. Due to its natural presence and to civil and militaries activities, general population can be exposed to U throughout drinking water or contaminated food. The pro/anti-oxidative system is a defense system which is often implicated in case of acute exposure to U. The aim of this thesis is to study the role of the pro/anti-oxidative system after chronic exposure to U in the liver and the kidney. After chronic exposure of rats to different U concentrations, this radionuclide accumulated in the organs in proportion to U intake; until 6 μg.g -1 of kidney tissues. U is localized in nucleus of the proximal tubular cells of the kidney. No nephrotoxicity was described even for the higher U level in drinking water and a reinforcement of the pro/anti-oxidative system with an increase in glutathione is observed. The study of U internal contamination in Nrf2 deficient mice, a cytoprotective transcription factor involved in the anti-oxidative defense has been realized. U accumulate more in Nrf2 mice than in WT mice but the biologic effects of U on the pro/anti-oxidative system did not seem to implicate Nrf2. At the cell level, a correlation between U distribution in HepG2 cells and the biological effects on this system is observed after U exposure at low concentrations. Soluble distribution of U is observed in cell nucleus. The apparition of U precipitates is correlated to the establishment of the adaptive mechanisms overtime which are overwhelmed and lead to a cellular toxicity at higher U level. In conclusion, these results suggest that the reinforcement of pro/anti-oxidative system could be an adaptive mechanism after chronic exposure at low U concentration. (author) [fr

  9. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris)

    Science.gov (United States)

    Moffat, Christopher; Pacheco, Joao Goncalves; Sharp, Sheila; Samson, Andrew J.; Bollan, Karen A.; Huang, Jeffrey; Buckland, Stephen T.; Connolly, Christopher N.

    2015-01-01

    The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombus terrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2 days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization in neurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies.—Moffat, C., Pacheco, J. G., Sharp, S., Samson, A. J., Bollan, K. A., Huang, J., Buckland, S. T., Connolly, C. N. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris). PMID:25634958

  10. Chronic ethanol exposure produces time- and brain region-dependent changes in gene coexpression networks.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Osterndorff-Kahanek

    Full Text Available Repeated ethanol exposure and withdrawal in mice increases voluntary drinking and represents an animal model of physical dependence. We examined time- and brain region-dependent changes in gene coexpression networks in amygdala (AMY, nucleus accumbens (NAC, prefrontal cortex (PFC, and liver after four weekly cycles of chronic intermittent ethanol (CIE vapor exposure in C57BL/6J mice. Microarrays were used to compare gene expression profiles at 0-, 8-, and 120-hours following the last ethanol exposure. Each brain region exhibited a large number of differentially expressed genes (2,000-3,000 at the 0- and 8-hour time points, but fewer changes were detected at the 120-hour time point (400-600. Within each region, there was little gene overlap across time (~20%. All brain regions were significantly enriched with differentially expressed immune-related genes at the 8-hour time point. Weighted gene correlation network analysis identified modules that were highly enriched with differentially expressed genes at the 0- and 8-hour time points with virtually no enrichment at 120 hours. Modules enriched for both ethanol-responsive and cell-specific genes were identified in each brain region. These results indicate that chronic alcohol exposure causes global 'rewiring' of coexpression systems involving glial and immune signaling as well as neuronal genes.

  11. Does chronic occupational exposure to volatile anesthetic agents influence the rate of neutrophil apoptosis?

    LENUS (Irish Health Repository)

    Goto, Y

    2012-02-03

    PURPOSE: The purpose of this preliminary investigation was to determine whether the rate of neutrophil apoptosis in health care workers is influenced by exposure to volatile anesthetic agents. METHODS: Percentage neutrophil apoptosis (Annexin-V FITC assay) was measured in health care workers (n = 20) and unexposed volunteers (n = 10). For the health care workers, time weighted personal exposure monitoring to N2O, sevoflurane and isoflurane was carried out. RESULTS: The sevoflurane and isoflurane concentrations to which health care workers were exposed were less than recommended levels in all 20 cases. Percent apoptosis was less at 24 (but not at one and 12) hr culture in health care workers [50.5 (9.7)%; P = 0.008] than in unexposed volunteers [57.3 (5.1)%]. CONCLUSION: Inhibition of neutrophil apoptosis at 24 hr culture was demonstrated in health care workers chronically exposed to volatile anesthetic agents. Exposure was well below recommended levels in the both scavenged and unscavenged work areas in which the study was carried out. Further study is required to assess the effect of greater degrees of chronic exposure to volatile anesthetic agents on neutrophil apoptosis.

  12. Occupational exposures and chronic kidney disease: Possible associations with endotoxin and ultrafine particles.

    Science.gov (United States)

    Sponholtz, Todd R; Sandler, Dale P; Parks, Christine G; Applebaum, Katie M

    2016-01-01

    Chronic kidney disease (CKD) carries a high public health burden yet there is limited research on occupational factors, which are examined in this retrospective case-control study. Newly diagnosed cases of CKD (n = 547) and controls (n = 508) from North Carolina provided detailed work histories in telephone interviews. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). There was heterogeneity in the association of CKD and agricultural work, with crop production associated with increased risk and work with livestock associated with decreased risk. Work with cutting/cooling/lubricating oils was associated with a reduced risk. CKD risk was increased for working in dusty conditions. CKD risk was reduced in subjects with occupational exposures previously reported to involve endotoxin exposure. Further, exposure to dusty conditions was consistently associated with increased risk of glomerulonephritis across industry, suggesting that research on CKD and ultrafine particulates is needed. © 2015 Wiley Periodicals, Inc.

  13. PASSIVE CAVITATION DETECTION DURING PULSED HIFU EXPOSURES OF EX VIVO TISSUES AND IN VIVO MOUSE PANCREATIC TUMORS

    Science.gov (United States)

    Li, Tong; Chen, Hong; Khokhlova, Tatiana; Wang, Yak-Nam; Kreider, Wayne; He, Xuemei; Hwang, Joo Ha

    2014-01-01

    Pulsed high-intensity focused ultrasound (pHIFU) has been demonstrated to enhance vascular permeability, disrupt tumor barriers and enhance drug penetration into tumor tissue through acoustic cavitation. Monitoring of cavitation activity during pHIFU treatments and knowing the ultrasound pressure levels sufficient to reliably induce cavitation in a given tissue are therefore very important. Here, three metrics of cavitation activity induced by pHIFU and evaluated by confocal passive cavitation detection were introduced: cavitation probability, cavitation persistence and the level of the broadband acoustic emissions. These metrics were used to characterize cavitation activity in several ex vivo tissue types (bovine tongue and liver and porcine adipose tissue and kidney) and gel phantoms (polyacrylamide and agarose) at varying peak-rarefactional focal pressures (1–12 MPa) during the following pHIFU protocol: frequency 1.1 MHz, pulse duration 1 ms, pulse repetition frequency 1 Hz. To evaluate the relevance of the measurements in ex vivo tissue, cavitation metrics were also investigated and compared in the ex vivo and in vivo murine pancreatic tumors that develop spontaneously in transgenic KPC mice and closely recapitulate human disease in their morphology. The cavitation threshold, defined at 50 % cavitation probability, was found to vary broadly among the investigated tissues (within 2.5–10 MPa), depending mostly on the water-lipid ratio that characterizes the tissue composition. Cavitation persistence and the intensity of broadband emissions depended both on tissue structure and lipid concentration. Both the cavitation threshold and broadband noise emission level were similar between ex vivo and in vivo pancreatic tumor tissue. The largest difference between in vivo and ex vivo settings was found in the pattern of cavitation occurrence throughout pHIFU exposure: it was sporadic in vivo, but ex vivo it decreased rapidly and stopped over the first few pulses

  14. Passive cavitation detection during pulsed HIFU exposures of ex vivo tissues and in vivo mouse pancreatic tumors.

    Science.gov (United States)

    Li, Tong; Chen, Hong; Khokhlova, Tatiana; Wang, Yak-Nam; Kreider, Wayne; He, Xuemei; Hwang, Joo Ha

    2014-07-01

    Pulsed high-intensity focused ultrasound (pHIFU) has been shown to enhance vascular permeability, disrupt tumor barriers and enhance drug penetration into tumor tissue through acoustic cavitation. Monitoring of cavitation activity during pHIFU treatments and knowing the ultrasound pressure levels sufficient to reliably induce cavitation in a given tissue are therefore very important. Here, three metrics of cavitation activity induced by pHIFU and evaluated by confocal passive cavitation detection were introduced: cavitation probability, cavitation persistence and the level of the broadband acoustic emissions. These metrics were used to characterize cavitation activity in several ex vivo tissue types (bovine tongue and liver and porcine adipose tissue and kidney) and gel phantoms (polyacrylamide and agarose) at varying peak-rare factional focal pressures (1-12 MPa) during the following pHIFU protocol: frequency 1.1 MHz, pulse duration 1 ms and pulse repetition frequency 1 Hz. To evaluate the relevance of the measurements in ex vivo tissue, cavitation metrics were also investigated and compared in the ex vivo and in vivo murine pancreatic tumors that develop spontaneously in transgenic KrasLSL.G12 D/+; p53 R172 H/+; PdxCretg/+ (KPC) mice and closely re-capitulate human disease in their morphology. The cavitation threshold, defined at 50% cavitation probability, was found to vary broadly among the investigated tissues (within 2.5-10 MPa), depending mostly on the water-lipid ratio that characterizes the tissue composition. Cavitation persistence and the intensity of broadband emissions depended both on tissue structure and lipid concentration. Both the cavitation threshold and broadband noise emission level were similar between ex vivo and in vivo pancreatic tumor tissue. The largest difference between in vivo and ex vivo settings was found in the pattern of cavitation occurrence throughout pHIFU exposure: it was sporadic in vivo, but it decreased rapidly and stopped

  15. Chronic lead exposure induces cochlear oxidative stress and potentiates noise-induced hearing loss.

    Science.gov (United States)

    Jamesdaniel, Samson; Rosati, Rita; Westrick, Judy; Ruden, Douglas M

    2018-08-01

    Acquired hearing loss is caused by complex interactions of multiple environmental risk factors, such as elevated levels of lead and noise, which are prevalent in urban communities. This study delineates the mechanism underlying lead-induced auditory dysfunction and its potential interaction with noise exposure. Young-adult C57BL/6 mice were exposed to: 1) control conditions; 2) 2 mM lead acetate in drinking water for 28 days; 3) 90 dB broadband noise 2 h/day for two weeks; and 4) both lead and noise. Blood lead levels were measured by inductively coupled plasma mass spectrometry analysis (ICP-MS) lead-induced cochlear oxidative stress signaling was assessed using targeted gene arrays, and the hearing thresholds were assessed by recording auditory brainstem responses. Chronic lead exposure downregulated cochlear Sod1, Gpx1, and Gstk1, which encode critical antioxidant enzymes, and upregulated ApoE, Hspa1a, Ercc2, Prnp, Ccl5, and Sqstm1, which are indicative of cellular apoptosis. Isolated exposure to lead or noise induced 8-12 dB and 11-25 dB shifts in hearing thresholds, respectively. Combined exposure induced 18-30 dB shifts, which was significantly higher than that observed with isolated exposures. This study suggests that chronic exposure to lead induces cochlear oxidative stress and potentiates noise-induced hearing impairment, possibly through parallel pathways. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Chronic caffeine exposure attenuates blast-induced memory deficit in mice.

    Science.gov (United States)

    Ning, Ya-Lei; Yang, Nan; Chen, Xing; Zhao, Zi-Ai; Zhang, Xiu-Zhu; Chen, Xing-Yun; Li, Ping; Zhao, Yan; Zhou, Yuan-Guo

    2015-01-01

    To investigate the effects of three different ways of chronic caffeine administration on blast- induced memory dysfunction and to explore the underlying mechanisms. Adult male C57BL/6 mice were used and randomly divided into five groups: control: without blast exposure, con-water: administrated with water continuously before and after blast-induced traumatic brain injury (bTBI), con-caffeine: administrated with caffeine continuously for 1 month before and after bTBI, pre-caffeine: chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI, post-caffeine: chronically administrated with caffeine after bTBI. After being subjected to moderate intensity of blast injury, mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1, 4, and 8 weeks post-blast injury. Neurological deficit scoring, glutamate concentration, proinflammatory cytokines production, and neuropathological changes at 24 h, 1, 4, and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages. Adenosine A1 receptor expression was detected using qPCR. All of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit, which is correlated with the neuroprotective effects against excitotoxicity, inflammation, astrogliosis and neuronal loss at different stages of injury. Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI; pre-bTBI and post-bTBI treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively. Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption. Since caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get, the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

  17. Chronic cyanidin-3-glucoside administration improves short-term spatial recognition memory but not passive avoidance learning and memory in streptozotocin-diabetic rats.

    Science.gov (United States)

    Nasri, Sima; Roghani, Mehrdad; Baluchnejadmojarad, Tourandokht; Balvardi, Mahboubeh; Rabani, Tahereh

    2012-08-01

    This research study was conducted to evaluate the efficacy of chronic cyanidin-3-glucoside (C3G) on alleviation of learning and memory deficits in diabetic rats as a result of the observed antidiabetic and antioxidant activity of C3G. Male Wistar rats were divided into control, diabetic, C3G-treated-control and -diabetic groups. The C3G was administered i.p. at a dose of 10 mg/kg on alternate days for eight weeks. For evaluation of learning and memory, initial latency (IL) and step-through latency (STL) were determined at the end of study using passive avoidance test. Meanwhile, spatial recognition memory was assessed as alternation in the Y-maze task. Oxidative stress markers in brain tissue were also measured. It was found that the alternation score of the diabetic rats was lower than that of control (p chronic C3G could improve short-term spatial recognition memory disturbance in the Y-maze test but not retention and recall capability in passive avoidance test in STZ-diabetic rats. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Acute but not chronic ethanol exposure impairs retinol oxidation in the small and large intestine of the rat

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Ellendt, K.; Lindros, K.

    2005-01-01

    BACKGROUND AND AIM: Ethanol has been shown to inhibit retinol oxidation at the level of alcohol dehydrogenase in liver and colon but not previously in the small intestine. In the present study we investigated how chronic alcohol feeding and acute ethanol exposure affects retinol dehydrogenase...... higher, respectively). While chronic alcohol feeding did not affect these parameters, acute ethanol exposure reduced V(max) and V(max)/K(m) dose-dependently (p

  19. Diffuse parenchymal lung disease in a case of chronic arsenic exposure

    Directory of Open Access Journals (Sweden)

    Somnath Bhattacharya

    2016-01-01

    Full Text Available A 42-year-old housewife, the resident of rural part of West Bengal, presented with gradually progressive exertional dyspnea associated with a dry cough for last 3 years clinical features were suggestive of diffuse parenchymal lung disease (DPLD. Her chest X-ray posteroanterior view and high resolution computed tomography scan of the thorax showed bilateral patchy ground glass opacities and reticulonodular pattern. Search for the etiology revealed classical skin findings of chronic arsenic exposure in the form of generalized darkening and thickening of skin and keratotic lesions over the palms and soles and classical raindrop pigmentation over leg which was present for last 7 years subsequently her bronchoalveolar lavage fluid, hair, nail, and drinking water showed significant amount of arsenic contamination. By exclusion of all known causes of DPLD, we concluded that it was a case of DPLD due to chronic arsenic exposure. To the best of our knowledge, only few case report of DPLD in chronic arsenicosis has been reported till date.

  20. Early histological and functional effects of chronic copper exposure in rat liver.

    Science.gov (United States)

    Cisternas, Felipe A; Tapia, Gladys; Arredondo, Miguel; Cartier-Ugarte, Denise; Romanque, Pamela; Sierralta, Walter D; Vial, María T; Videla, Luis A; Araya, Magdalena

    2005-10-01

    Cu is an essential trace element capable of producing toxic effects in animals and man when ingested acutely or chronically in excess. Although chronic Cu exposure is increasingly recognized as a public health issue, its early effects remain largely unknown. We approached the significance of a moderate chronic Cu load in young rats to correlate early hepatic histopathological changes with functional alterations of liver cells. For this purpose, supplementation with 1,200 ppm of Cu in rat food for 16 weeks was chosen. In these conditions, Cu load elicited a significant decrease in growth curves. There were mild light microscopy alterations in Cu-treated rats, although increasing intracellular Cu storage was correlated with longer Cu exposure both by histological and biochemical measurements. Ultrastructural alterations included lysosomal inclusions as well as mitochondrial and nuclear changes. Liver perfusion studies revealed higher rates of basal O(2) consumption and colloidal carbon-induced O(2) uptake in Cu-treated rats, with enhanced carbon-induced O(2)/carbon uptake ratios and NF-kappaB DNA binding activity. These changes were time-dependent and returned to control values after 12 or 16 weeks. It is concluded that subchronic Cu loading in young rats induces early hepatic morphological changes, with enhancement in Küpffer cell-dependent respiratory burst activity and NF-kappaB DNA binding, cellular responses that may prevent or alleviate the hepatotoxicity of the metal.

  1. Effects of chronic occupational exposure to anaesthetic gases on the rate of neutrophil apoptosis among anaesthetists.

    LENUS (Irish Health Repository)

    Tyther, R

    2012-02-03

    BACKGROUND AND OBJECTIVE: Volatile anaesthetic agents are known to influence neutrophil function. The aim was to determine the effect of chronic occupational exposure to volatile anaesthetic agents on the rate of neutrophil apoptosis among anaesthetists. To test this hypothesis, we compared the rate of neutrophil apoptosis in anaesthetists who had been chronically exposed to volatile anaesthetic agents with that in unexposed volunteers. METHODS: Venous blood (20 mL) was withdrawn from 24 ASA I-II volunteers, from which neutrophils were isolated, and maintained in culture. At 1, 12 and 24 h in culture, the percentage of neutrophil apoptosis was assessed by dual staining with annexin V-FITC and propidium iodide. RESULTS: At 1 h (but not at 12 and 24 h) in culture, the rate of neutrophil apoptosis was significantly less in the anaesthetists--13.8 (12.9%) versus 34.4 (12.1%) (P = 0.001). CONCLUSIONS: Chronic occupational exposure to volatile anaesthetic agents may inhibit neutrophil apoptosis. This may have implications for anaesthetists and similarly exposed healthcare workers in terms of the adequacy of their inflammatory response.

  2. Striatal proteomic analysis suggests that first L-dopa dose equates to chronic exposure.

    Directory of Open Access Journals (Sweden)

    Birger Scholz

    Full Text Available L-3,4-dihydroxypheylalanine (L-dopa-induced dyskinesia represent a debilitating complication of therapy for Parkinson's disease (PD that result from a progressive sensitization through repeated L-dopa exposures. The MPTP macaque model was used to study the proteome in dopamine-depleted striatum with and without subsequent acute and chronic L-dopa treatment using two-dimensional difference in-gel electrophoresis (2D-DIGE and mass spectrometry. The present data suggest that the dopamine-depleted striatum is so sensitive to de novo L-dopa treatment that the first ever administration alone would be able (i to induce rapid post-translational modification-based proteomic changes that are specific to this first exposure and (ii, possibly, lead to irreversible protein level changes that would be not further modified by chronic L-dopa treatment. The apparent equivalence between first and chronic L-dopa administration suggests that priming would be the direct consequence of dopamine loss, the first L-dopa administrations only exacerbating the sensitization process but not inducing it.

  3. Chronic corticosterone exposure reduces hippocampal glycogen level and induces depression-like behavior in mice.

    Science.gov (United States)

    Zhang, Hui-yu; Zhao, Yu-nan; Wang, Zhong-li; Huang, Yu-fang

    2015-01-01

    Long-term exposure to stress or high glucocorticoid levels leads to depression-like behavior in rodents; however, the cause remains unknown. Increasing evidence shows that astrocytes, the most abundant cells in the central nervous system (CNS), are important to the nervous system. Astrocytes nourish and protect the neurons, and serve as glycogen repositories for the brain. The metabolic process of glycogen, which is closely linked to neuronal activity, can supply sufficient energy substrates for neurons. The research team probed into the effects of chronic corticosterone (CORT) exposure on the glycogen level of astrocytes in the hippocampal tissues of male C57BL/6N mice in this study. The results showed that chronic CORT injection reduced hippocampal neurofilament light protein (NF-L) and synaptophysin (SYP) levels, induced depression-like behavior in male mice, reduced hippocampal glycogen level and glycogen synthase activity, and increased glycogen phosphorylase activity. The results suggested that the reduction of the hippocampal glycogen level may be the mechanism by which chronic CORT treatment damages hippocampal neurons and induces depression-like behavior in male mice.

  4. The role of environmental tobacco exposure and Helicobacter pylori infection in the risk of chronic tonsillitis in children

    Directory of Open Access Journals (Sweden)

    Chen Li’e

    Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Helicobacter pylori (H. pylori is a chronic infectious pathogen with high prevalence. This study investigated the interaction between environmental tobacco exposure and H. pylori infection on the incidence of chronic tonsillitis in Chinese children. DESIGN AND SETTING: Cross-sectional study performed in an outpatient clinic in China. METHODS: Pediatric patients with chronic tonsillitis were enrolled. H. pylori infection was determined according to the presence of H. pylori CagA IgG antibodies. Serum cotinine levels and environmental tobacco smoke (ETS exposure were determined for all participants. RESULTS: There was no significant difference in H. pylori infection between the children with chronic tonsillitis and children free of disease, but there was a significant difference in ETS between the two groups (P = 0.011. We next studied the association between ETS and chronic tonsillitis based on H. pylori infection status. In the patients with H. pylori infection, there was a significant difference in ETS distribution between the chronic tonsillitis and control groups (P = 0.022. Taking the participants without ETS as the reference, multivariate logistic regression analysis showed that those with high ETS had higher susceptibility to chronic tonsillitis (adjusted OR = 2.33; 95% CI: 1.67-3.25; adjusted P < 0.001. However, among those without H. pylori infection, ETS did not predispose towards chronic tonsillitis. CONCLUSION: Our findings suggest that tobacco exposure should be a putative mediator risk factor to chronic tonsillitis among children with H. pylori infection.

  5. Chronic exposure to zinc oxide nanoparticles increases ischemic-reperfusion injuries in isolated rat hearts

    Energy Technology Data Exchange (ETDEWEB)

    Milivojević, Tamara; Drobne, Damjana; Romih, Tea; Mali, Lilijana Bizjak [University of Ljubljana, Department of Biology, Biotechnical Faculty (Slovenia); Marin, Irena; Lunder, Mojca; Drevenšek, Gorazd, E-mail: gorazd.drevensek@mf.uni-lj.si [University of Ljubljana, Institute of Pharmacology and Experimental Toxicology, Faculty of Medicine (Slovenia)

    2016-10-15

    The use of zinc oxide nanoparticles (ZnO NPs) in numerous products is increasing, although possible negative implications of their long-term consumption are not known yet. Our aim was to evaluate the chronic, 6-week oral exposure to two different concentrations of ZnO NPs on isolated rat hearts exposed to ischemic-reperfusion injury and on small intestine morphology. Wistar rats of both sexes (n = 18) were randomly divided into three groups: (1) 4 mg/kg ZnO NPs, (2) 40 mg/kg ZnO NPs, and (3) control. After 6 weeks of treatment, the hearts were isolated, the left ventricular pressure (LVP), the coronary flow (CF), the duration of arrhythmias and the lactate dehydrogenase release rate (LDH) were measured. A histological investigation of the small intestine was performed. Chronic exposure to ZnO NPs acted cardiotoxic dose-dependently. ZnO NPs in dosage 40 mg/kg maximally decreased LVP (3.3-fold) and CF (2.5-fold) and increased the duration of ventricular tachycardia (all P < 0.01) compared to control, whereas ZnO NPs in dosage 4 mg/kg acted less cardiotoxic. Goblet cells in the small intestine epithelium of rats, treated with 40 mg ZnO NPs/kg, were enlarged, swollen and numerous, the intestinal epithelium width was increased. Unexpectedly, ZnO NPs in both dosages significantly decreased LDH. A 6-week oral exposure to ZnO NPs dose-dependently increased heart injuries and caused irritation of the intestinal mucosa. A prolonged exposure to ZnO NPs might cause functional damage to the heart even with exposures to the recommended daily doses, which should be tested in future studies.

  6. The impairment of learning and memory and synaptic loss in mouse after chronic nitrite exposure.

    Science.gov (United States)

    Chen, Yongfang; Cui, Zhanjun; Wang, Lai; Liu, Hongliang; Fan, Wenjuan; Deng, Jinbo; Deng, Jiexin

    2016-12-01

    The objective of this study is to understand the impairment of learning and memory in mouse after chronic nitrite exposure. The animal model of nitrite exposure in mouse was created with the daily intubation of nitrite in adult healthy male mice for 3 months. Furthermore, the mouse's learning and memory abilities were tested with Morris water maze, and the expression of Synaptophysin and γ-Synuclein was visualized with immunocytochemistry and Western blot. Our results showed that nitrite exposure significantly prolonged the escape latency period (ELP) and decreased the values of the frequency across platform (FAP) as well as the accumulative time in target quadrant (ATITQ) compared to control, in dose-dependent manner. In addition, after nitrite exposure, synaptophysin (SYN) positive buttons in the visual cortex was reduced, in contrast the increase of γ-synuclein positive cells. The results above were supported by Western blot as well. We conclude that nitrite exposure could lead to a decline in mice's learning and memory. The overexpression of γ-synuclein contributed to the synaptic loss, which is most likely the cause of learning and memory impairment. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1720-1730, 2016. © 2015 Wiley Periodicals, Inc.

  7. Effects of chronic carbon monoxide exposure on fetal growth and development in mice

    Directory of Open Access Journals (Sweden)

    Venditti Carolina C

    2011-12-01

    Full Text Available Abstract Background Carbon monoxide (CO is produced endogenously, and can also be acquired from many exogenous sources: ie. cigarette smoking, automobile exhaust. Although toxic at high levels, low level production or exposure lends to normal physiologic functions: smooth muscle cell relaxation, control of vascular tone, platelet aggregation, anti- inflammatory and anti-apoptotic events. In pregnancy, it is unclear at what level maternal CO exposure becomes toxic to the fetus. In this study, we hypothesized that CO would be embryotoxic, and we sought to determine at what level of chronic CO exposure in pregnancy embryo/fetotoxic effects are observed. Methods Pregnant CD1 mice were exposed to continuous levels of CO (0 to 400 ppm from conception to gestation day 17. The effect on fetal/placental growth and development, and fetal/maternal CO concentrations were determined. Results Maternal and fetal CO blood concentrations ranged from 1.12- 15.6 percent carboxyhemoglobin (%COHb and 1.0- 28.6%COHb, respectively. No significant difference was observed in placental histological morphology or in placental mass with any CO exposure. At 400 ppm CO vs. control, decreased litter size and fetal mass (p Conclusions Exposure to levels at or below 300 ppm CO throughout pregnancy has little demonstrable effect on fetal growth and development in the mouse.

  8. Chronic exposure to trichloroethene causes early onset of SLE-like disease in female MRL +/+ mice

    International Nuclear Information System (INIS)

    Cai Ping; Koenig, Rolf; Boor, Paul J.; Kondraganti, Shakuntala; Kaphalia, Bhupendra S.; Khan, M. Firoze; Ansari, G.A.S.

    2008-01-01

    Trichloroethene (TCE) exacerbates the development of autoimmune responses in autoimmune-prone MRL +/+ mice. Although TCE-mediated autoimmune responses are associated with an increase in serum immunoglobulins and autoantibodies, the underlying mechanism of autoimmunity is not known. To determine the progression of TCE-mediated immunotoxicity, female MRL +/+ mice were chronically exposed to TCE through the drinking water (0.5 mg/ml of TCE) for various periods of time. Serum concentrations of antinuclear antibodies increased after 36 and 48 weeks of TCE exposure. Histopathological analyses showed lymphocyte infiltration in the livers of MRL +/+ mice exposed to TCE for 36 or 48 weeks. Lymphocyte infiltration was also apparent in the pancreas, lungs, and kidneys of mice exposed to TCE for 48 weeks. Immunoglobulin deposits in kidney glomeruli were found after 48 weeks of exposure to TCE. Our results suggest that chronic exposure to TCE promotes inflammation in the liver, pancreas, lungs, and kidneys, which may lead to SLE-like disease in MRL +/+ mice

  9. Chronic prenatal caffeine exposure impairs novel object recognition and radial arm maze behaviors in adult rats.

    Science.gov (United States)

    Soellner, Deborah E; Grandys, Theresa; Nuñez, Joseph L

    2009-12-14

    In this report, we demonstrate that chronic prenatal exposure to a moderate dose of caffeine disrupts novel object recognition and radial arm maze behaviors in adult male and female rats. Pregnant dams were administered either tap water or 75 mg/L caffeinated tap water throughout gestation. Oral self-administration in the drinking water led to an approximate maternal intake of 10mg/kg/day, equivalent to 2-3 cups of coffee/day in humans based on a metabolic body weight conversion. In adulthood, the offspring underwent testing on novel object recognition, radial arm maze, and Morris water maze tasks. Prenatal caffeine exposure was found to impair 24-h memory retention in the novel object recognition task and impair both working and reference memory in the radial arm maze. However, prenatal caffeine exposure did not alter Morris water maze performance in either a simple water maze procedure or in an advanced water maze procedure that included reversal and working memory paradigms. These findings demonstrate that chronic oral intake of caffeine throughout gestation can alter adult cognitive behaviors in rats.

  10. Chronic Exposure to Particulate Nickel Induces Neoplastic Transformation in Human Lung Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Amie L. Holmes

    2013-11-01

    Full Text Available Nickel is a well-known human lung carcinogen with the particulate form being the most potent; however, the carcinogenic mechanism remains largely unknown. Few studies have investigated the genotoxicity and carcinogenicity of nickel in its target cell, human bronchial epithelial cells. Thus, the goal of this study was to investigate the effects of particulate nickel in human lung epithelial cells. We found that nickel subsulfide induced concentration- and time-dependent increases in both cytotoxicity and genotoxicity in human lung epithelial cells (BEP2D. Chronic exposure to nickel subsulfide readily induced cellular transformation, inducing 2.55, 2.9 and 2.35 foci per dish after exposure to 1, 2.5 and 5 μg/cm2 nickel subsulfide, respectively. Sixty-one, 100 and 70 percent of the foci isolated from 1, 2.5, and 5 μg/cm2 nickel subsulfide treatments formed colonies in soft agar and the degree of soft agar colony growth increased in a concentration-dependent manner. Thus, chronic exposure to particulate nickel induces genotoxicity and cellular transformation in human lung epithelial cells.

  11. Behavioural responses of Acroneuria lycoria (Ins. Plecopt. ) Larvae to acute and chronic acid exposure

    Energy Technology Data Exchange (ETDEWEB)

    McNichol, R.E.; Scherer, E.

    1987-01-01

    This study was designed to investigate the responses of a perlid stonefly, Acroneuria lycorias (Newman), to acute and chronic acid exposure. Larvae of this species are common in streams and rivers impacted by acidic precipitation. It is also a suggested standard toxicity test species, which in previous studies has proven to be very sensitive to some toxicants. The effects of acute and chronic acid exposure on the locomotor activity, microdistribution, and drift behaviour of the stonefly larvae were studied in laboratory streams. When subjected to a reduction in pH from 8.1 to 2.5 over an 8-h period, larvae showed little behavioural response down to pH 4.2. As the pH fell to 3.0, head-rubbing activity appeared and increased in frequency. At pH 3.0 and below, larvae showed increased gill-ventilatory movements and locomotor activity. Most larvae died within 14 h of exposure to pH 2.5; however, they did not abandon their preferred refuges before death. Larvae exposed to 5 pH levels between 4.5 and 8.2 for 30-50 d displayed no significant changes in locomotor activity, drift behaviour or microdistribution when compared to control animals. Results indicate that later instar larvae of this species are relatively acid tolerant. 29 refs 4 figs 1 tab

  12. Effects of chronic alternating cadmium exposure on the episodic secretion of prolactin in male rats

    Energy Technology Data Exchange (ETDEWEB)

    Esquifino, A.I. [Madrid Univ. (Spain). Facultad de Medicina Complutense; Marquez, N.; Alvarez-Demanuel, E.; Lafuente, A. [Vigo Univ., Orense (Spain). Lab. de Toxicologia

    1998-07-01

    Cadmium increases or decreases prolactin secretion depending on the dose and duration of the exposure to the metal. However, whether there are cadmium effects on the episodic prolactin secretion is less well known. This study was undertaken to address whether chronic alternating exposure to two different doses of cadmium affects the episodic pattern of prolactin and to what extent the effects of cadmium are age-dependent. Male rats were treated s.c. with cadmium chloride (0.5 or 1.0 mg/kg) from day 30 to 60, or from day 60 to 90 of age, with alteration of the doses every 4 days, starting with the smaller dose. Controls received vehicle every 4 days. The last dose of cadmium was given 48 h prior to the pulsatility study. Prolactin secretion in the 4 experimental groups studied was episodic and changed significantly after cadmium exposure. Cadmium administration from day 30 to 60 of life significantly decreased the mean half-life of prolactin. On the other hand, when administered from day 60 to 90 cadmium significantly decreased the mean as well as serum prolactin levels and the absolute amplitude of the prolactin pulses, their duration, the relative amplitude or the mean half-life of the hormone. The frequency of prolactin peaks was not changed by cadmium administration. The results indicate that low intermittent doses of cadmium chronically administered change the episodic secretion pattern of prolactin in rats. The effects of cadmium on prolactin secretion were age dependent. (orig.)

  13. Active or passive exposure to tobacco smoking and allergic rhinitis, allergic dermatitis, and food allergy in adults and children: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Jurgita Saulyte

    2014-03-01

    Full Text Available Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS or passive exposure to secondhand smoke and allergic conditions.We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR or relative risk (RR estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children. We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR, allergic rhinitis was not associated with active smoking (pooled RR, 1.02 [95% CI 0.92-1.15], but was associated with passive smoking (pooled RR 1.10 [95% CI 1.06-1.15]. Allergic dermatitis was associated with both active (pooled RR, 1.21 [95% CI 1.14-1.29] and passive smoking (pooled RR, 1.07 [95% CI 1.03-1.12]. In children and adolescent, allergic rhinitis was associated with active (pooled RR, 1.40 (95% CI 1.24-1.59 and passive smoking (pooled RR, 1.09 [95% CI 1.04-1.14]. Allergic dermatitis was associated with active (pooled RR, 1.36 [95% CI 1.17-1.46] and passive smoking (pooled RR, 1.06 [95% CI 1.01-1.11]. Food allergy was associated with SHS (1

  14. Persistent modification of Nav1.9 following chronic exposure to insecticides and pyridostigmine bromide

    International Nuclear Information System (INIS)

    Nutter, Thomas J.; Cooper, Brian Y.

    2014-01-01

    Many veterans of the 1991 Gulf War (GW) returned from that conflict with a widespread chronic pain affecting deep tissues. Recently, we have shown that a 60 day exposure to the insecticides permethrin, chlorpyrifos, and pyridostigmine bromide (NTPB) had little influence on nociceptor action potential forming Na v 1.8, but increased K v 7 mediated inhibitory currents 8 weeks after treatment. Using the same exposure regimen, we used whole cell patch methods to examine whether the influences of NTPB could be observed on Na v 1.9 expressed in muscle and vascular nociceptors. During a 60 day exposure to NTPB, rats exhibited lowered muscle pain thresholds and increased rest periods, but these measures subsequently returned to normal levels. Eight and 12 weeks after treatments ceased, DRG neurons were excised from the sensory ganglia. Whole cell patch studies revealed little change in voltage dependent activation and deactivation of Na v 1.9, but significant increases in the amplitude of Na v 1.9 were observed 8 weeks after exposure. Cellular studies, at the 8 week delay, revealed that NTPB also significantly prolonged action potential duration and afterhyperpolarization (22 °C). Acute application of permethrin (10 μM) also increased the amplitude of Na v 1.9 in skin, muscle and vascular nociceptors. In conclusion, chronic exposure to Gulf War agents produced long term changes in the amplitude of Na v 1.9 expressed in muscle and vascular nociceptors. The reported increases in K v 7 amplitude may have been an adaptive response to increased Na v 1.9, and effectively suppressed behavioral pain measures in the post treatment period. Factors that alter the balance between Na v 1.9 and K v 7 could release spontaneous discharge and produce chronic deep tissue pain. - Highlights: • Rats were treated 60 days with permethrin, chlorpyrifos and pyridostigmine bromide. • 8 weeks after treatments, Nav1.9 activation and deactivation were unchanged. • The amplitude and

  15. [The consequences of passive smoking in adults].

    Science.gov (United States)

    Trédaniel, J; Savinelli, F; Vignot, S; Bousquet, G; Le Maignan, C; Misset, J-L

    2006-04-01

    Passive smoking is the involuntary inhalation by a non-smoker of smoke generated in his neighbourhood by one or more smokers. The effect of this exposure is already generally recognised in children. In adults the induction of chronic obstructive lung disease has not been demonstrated. This is no longer the case for ischaemic heart disease and lung cancer where the effect of passive exposure of non-smokers to cigarette smoke is recognised. The biological plausibility together with the concordance of results obtained over successive years, as well as the large numbers of patients included in the studies, lead to a confident conclusion that the risks in adult non-smokers are increased by the order of 25%. There is no evidence that bias affects the conclusions reached and the World Health Organisation has recently classified passive smoking as being carcinogenic in man. As a result of these data prevention of passive exposure to cigarette smoke should be part of a larger framework of smoking prevention, especially among the young.

  16. Renal effects of chronic exposure to organic solvents. A clinical controlled trial

    Energy Technology Data Exchange (ETDEWEB)

    Krusell, L.; Nielsen, H.K.; Baelum, J.; Lundqvist, G.; Omland, O.; Vaeth, M.; Husted, S.E.; Mogensen, C.E.; Geday, E.

    1985-01-01

    Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin. This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers.

  17. Renal effects of chronic exposure to organic solvents. A clinical controlled trial

    DEFF Research Database (Denmark)

    Krusell, Lars Romer; Nielsen, H K; Bælum, Jesper

    1985-01-01

    Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age......-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin....... This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers....

  18. Optimizing the use of on-street car parking system as a passive control of air pollution exposure in street canyons by large eddy simulation

    Science.gov (United States)

    Gallagher, J.; Gill, L. W.; McNabola, A.

    2011-03-01

    An investigation was carried out to establish the effectiveness of parked cars in urban street canyons as passive controls on pedestrian pollutant exposure. A numerical model of a generic street canyon was developed using a large eddy simulation (LES) model to compare personal exposure on the footpath with and without the presence of parked cars. Three configurations of car parking systems were investigated (parallel, perpendicular and 45° parking) in addition to the influence of wind speed, wind direction and car parking occupancy. A tracer gas (CO 2) was used as a representative pollutant from vehicular sources within the street canyon models. The results indicated that parked cars may act as a temporary baffle plate between traffic emissions and pedestrians on the footpath. Reductions in exposure of up to 35% and 49% were attained on the leeward and windward footpaths in perpendicular wind conditions, with parallel winds allowing up to 33% pollutant reduction on both footpaths for parallel parking. The perpendicular and 45° car parking configurations investigated proved less successful as passive controls on air pollution exposure and an increase in pollutant concentration occurred in some models. An investigation of parking space occupancy rates was carried out for parallel parked cars. The fraction of parked cars influenced the level of reduction of pollutants on the footpaths with steady reductions in perpendicular winds, yet reductions were only evident for occupancy rates greater than approximately 45% in parallel wind conditions. One negative impact associated with the parked cars study was the increase of pollutant levels on the roadway as the parked cars acted as a baffle wall, which trapped pollutants in the road. The paper underlines the potential of on-street car parking for reducing the personal exposure of pollutants by pedestrians and the optimum parking layout to achieve maximum health protection.

  19. Impact of passive smoking, cooking with solid fuel exposure, and MBL/MASP-2 gene polymorphism upon susceptibility to tuberculosis

    Directory of Open Access Journals (Sweden)

    Mengshi Chen

    2014-12-01

    Conclusions: Passive smoking, cooking with solid fuel, and polymorphisms of MBL (rs7096206 and MASP-2 (rs6695096 genes were associated with susceptibility to TB in non-smokers, and there were gene–environment interactions among them. Further studies are needed to explore details of the mechanisms of association.

  20. Chronic exposure to graphene-based nanomaterials induces behavioral deficits and neural damage in Caenorhabditis elegans.

    Science.gov (United States)

    Li, Ping; Xu, Tiantian; Wu, Siyu; Lei, Lili; He, Defu

    2017-10-01

    Nanomaterials of graphene and its derivatives have been widely applied in recent years, but whose impacts on the environment and health are still not well understood. In the present study, the potential adverse effects of graphite (G), graphite oxide nanoplatelets (GO) and graphene quantum dots (GQDs) on the motor nervous system were investigated using nematode Caenorhabditis elegans as the assay system. After being characterized using TEM, SEM, XPS and PLE, three nanomaterials were chronically exposed to C. elegans for 6 days. In total, 50-100 mg l -1 GO caused a significant reduction in the survival rate, but G and GDDs showed low lethality on nematodes. After chronic exposure of sub-lethal dosages, three nanomaterials were observed to distribute primarily in the pharynx and intestine; but GQDs were widespread in nematode body. Three graphene-based nanomaterials resulted in significant declines in locomotor frequency of body bending, head thrashing and pharynx pumping. In addition, mean speed, bending angle-frequency and wavelength of the crawling movement were significantly reduced after exposure. Using transgenic nematodes, we found high concentrations of graphene-based nanomaterials induced down-expression of dat-1::GFP and eat-4::GFP, but no significant changes in unc-47::GFP. This indicates that graphene-based nanomaterials can lead to damages in the dopaminergic and glutamatergic neurons. The present data suggest that chronic exposure of graphene-based nanomaterials may cause neurotoxicity risks of inducing behavioral deficits and neural damage. These findings provide useful information to understand the toxicity and safe application of graphene-based nanomaterials. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Chronic Ethanol Exposure Effects on Vitamin D Levels among Subjects with Alcohol Use Disorder

    Directory of Open Access Journals (Sweden)

    Olalekan Ogunsakin

    2016-01-01

    Full Text Available Vitamin D has been previously recognized to play important roles in human immune system and function. In the pulmonary system, vitamin D regulates the function of antimicrobial peptides, especially cathelicidin/LL-37. Human cathelicidin/LL-37 is a bactericidal, bacteriostatic, and antiviral endogenous peptide with protective immune functions. Chronic exposure to excessive alcohol has the potential to reduce levels of vitamin D (inactive vitamin D [25(OHD 3 ] and active vitamin D [1, 25(OH 2 D 3 ] and leads to downregulation of cathelicidin/LL-37. Alcohol-mediated reduction of LL-37 may be partly responsible for increased incidence of more frequent and severe respiratory infections among subjects with alcohol use disorder (AUD. The objective of this study was to investigate the mechanisms by which alcohol exerts its influence on vitamin D metabolism. In addition, the aim was to establish associations between chronic alcohol exposures, levels of pulmonary vitamin D, and cathelicidin/LL-37 using broncho-alveolar lavage fluid samples of subjects with AUD and healthy controls. Findings from the experiment showed that levels of inactive vitamin D (25(OHD 3 , active vitamin D (1, 25(OH 2 D 3 , cathelicidin/LL-37, and CYP27B1 proteins were significantly reduced ( P < 0.05 when compared with the matched healthy control group. However, CYP2E1 was elevated in all the samples examined. Chronic exposure to alcohol has the potential to reduce the levels of pulmonary vitamin D and results in subsequent downregulation of the antimicrobial peptide, LL-37, in the human pulmonary system.

  2. Reduced gene expression levels after chronic exposure to high concentrations of air pollutants

    Czech Academy of Sciences Publication Activity Database

    Rössner ml., Pavel; Tulupová, Elena; Rössnerová, Andrea; Líbalová, Helena; Hoňková, Kateřina; Gmuender, H.; Pastorková, Anna; Švecová, Vlasta; Topinka, Jan; Šrám, Radim

    2015-01-01

    Roč. 780, oct (2015), s. 60-70 ISSN 0027-5107 R&D Projects: GA MŽP(CZ) SP/1B3/8/08; GA MŠk(CZ) LO1508; GA ČR GA13-13458S; GA MŠk 2B08005 Institutional support: RVO:68378041 Keywords : chronic exposure * air pollution * gene expression profiles * human health * particulate matter * polycyclic aromatic hydrocarbons Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.581, year: 2015

  3. Early and late radiation response of human skin following chronic exposure of the hands

    International Nuclear Information System (INIS)

    Lenz, U.; Arndt, D.; Thormann, T.

    1979-01-01

    Clinical examinations on 45 radiation workers with chronical low-level exposures to their hands revealed that accumulated doses in the range of 15 to 30 Sv (1500 to 3000 rem) may already produce macroscopically unconspicuous early alterations of the vessel system within the corium as well as epidermal hyperplasia. Therefore, the annual permissible dose equivalent of 0.75 Sv (75 rem) recommended by ICRP for the skin of the extremities appears unjustifiably high and should be reduced to 0.30 Sv (30 rem), the limit valid for the remaining areas of skin. (author)

  4. Sub-chronic lung inflammation after airway exposures to Bacillus thuringiensis biopesticides in mice

    Directory of Open Access Journals (Sweden)

    Barfod Kenneth K

    2010-09-01

    exposures to commercial Bt based biopesticides can induce sub-chronic lung inflammation in mice, which may be the first step in the development of chronic lung diseases. Inhalation of Bt aerosols does not induce airway irritation, which could explain why workers may be less inclined to use a filter mask during the application process, and are thereby less protected from exposure to Bt spores.

  5. Changes in lymphocytes size under chronic exposure of the organism to factors of radiation and chemical origin

    International Nuclear Information System (INIS)

    Ivanov, V.V.

    1990-01-01

    Results of the analysis of changes in peripheral blood lymphocytes size under chronic exposure to external gamma radiation and pesticide chlorofoz in combination and separately are presented. It has been found out that under exposure of animals to radiation or the pesticide it is small and big lymphocytes respectively which most significantly suffer quantitatively. Under the joint radiational-chemical exposure of the organism the number of both types of cells is reduced simultaneously

  6. Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, S., E-mail: up201208875@fc.up.pt [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Antunes, S.C. [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Correia, A.T. [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Faculdade de Ciências da Saúde da Universidade Fernando Pessoa (FCS-UFP), Rua Carlos da Maia, 296, 4200–150, Porto (Portugal); Nunes, B. [Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810–193 Aveiro (Portugal); Departamento de Biologia, Universidade de Aveiro, Campus de Santiago, 3810–193 Aveiro (Portugal)

    2016-03-01

    Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by

  7. Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Rodrigues, S.; Antunes, S.C.; Correia, A.T.; Nunes, B.

    2016-01-01

    Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by

  8. Modeling accumulations of particles in lung during chronic inhalation exposures that lead to impaired clearance

    International Nuclear Information System (INIS)

    Wolff, R.K.; Griffith, W.C. Jr.; Cuddihy, R.G.; Snipes, M.B.; Henderson, R.F.; Mauderly, J.L.; McClellan, R.O.

    1989-01-01

    Chronic inhalation of insoluble particles of low toxicity that produce substantial lung burdens of particles, or inhalation of particles that are highly toxic to the lung, can impair clearance. This report describes model calculations of accumulations in lung of inhaled low-toxicity diesel exhaust soot and high-toxicity Ga2O3 particles. Lung burdens of diesel soot were measured periodically during a 24-mo exposure to inhaled diesel exhaust at soot concentrations of 0, 0.35, 3.5, and 7 mg m-3, 7 h d-1, 5 d wk-1. Lung burdens of Ga2O3 were measured for 1 y after a 4-wk exposure to 23 mg Ga2O3 m-3, 2 h d-1, 5 d wk-1. Lung burdens of Ga2O3 were measured for 1 y both studies using inhaled radiolabeled tracer particles. Simulation models fit the observed lung burdens of diesel soot in rats exposed to the 3.5- and 7-mg m-3 concentrations of soot only if it was assumed that clearance remained normal for several months, then virtually stopped. Impaired clearance from high-toxicity particles occurred early after accumulations of a low burden, but that from low-toxicity particles was evident only after months of exposure, when high burdens had accumulated in lung. The impairment in clearances of Ga2O3 particles and radiolabeled tracers was similar, but the impairment in clearance of diesel soot and radiolabeled tracers differed in magnitude. This might have been related to differences in particle size and composition between the tracers and diesel soot. Particle clearance impairment should be considered both in the design of chronic exposures of laboratory animals to inhaled particles and in extrapolating the results to people

  9. Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Saima Naz and Muhammad Javed

    2013-07-01

    Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

  10. Passive control potentials of trees and on-street parked cars in reduction of air pollution exposure in urban street canyons

    International Nuclear Information System (INIS)

    Abhijith, K.V.; Gokhale, Sharad

    2015-01-01

    This study investigates the passive-control-potentials of trees and on-street parked cars on pedestrian exposure to air pollutants in a street canyon using three-dimensional CFD. Since, according to some studies trees deteriorate air quality and cars parked roadside improve it, the combine as well as separate effects of trees and on-street parked cars have been examined. For this, different tree canopy layouts and parking configurations have been developed and pedestrian exposure for each has been analysed. The results showed, for example, tree crown with high porosity and low-stand density in combination with parallel or perpendicular car parking reduced the pedestrian exposure considerably. - Highlights: • Trees and on-street parked cars can manipulate pollutant levels in street canyons. • Low stand density trees with 0° or 90° car parking reduce pedestrian exposure. • Trees with medium crown, high porosity, low stand density reduce pollutant levels. - This study investigated the combination of trees and on-street parked cars to manipulate pollutant levels in urban street canyons to reduce pedestrian exposure

  11. Autophagy deficiency in macrophages enhances NLRP3 inflammasome activity and chronic lung disease following silica exposure

    International Nuclear Information System (INIS)

    Jessop, Forrest; Hamilton, Raymond F.; Rhoderick, Joseph F.; Shaw, Pamela K.; Holian, Andrij

    2016-01-01

    Autophagy is an important metabolic mechanism that can promote cellular survival following injury. The specific contribution of autophagy to silica-induced inflammation and disease is not known. The objective of these studies was to determine the effects of silica exposure on the autophagic pathway in macrophages, as well as the general contribution of autophagy in macrophages to inflammation and disease. Silica exposure enhanced autophagic activity in vitro in Bone Marrow derived Macrophages and in vivo in Alveolar Macrophages isolated from silica-exposed mice. Impairment of autophagy in myeloid cells in vivo using Atg5 fl/fl LysM-Cre + mice resulted in enhanced cytotoxicity and inflammation after silica exposure compared to littermate controls, including elevated IL-18 and the alarmin HMGB1 in the whole lavage fluid. Autophagy deficiency caused some spontaneous inflammation and disease. Greater silica-induced acute inflammation in Atg5 fl/fl LysM-Cre + mice correlated with increased fibrosis and chronic lung disease. These studies demonstrate a critical role for autophagy in suppressing silica-induced cytotoxicity and inflammation in disease development. Furthermore, this data highlights the importance of basal autophagy in macrophages and other myeloid cells in maintaining lung homeostasis. - Highlights: • Silica exposure increases autophagy in macrophages. • Autophagy deficient mice have enhanced inflammation and silicosis. • Autophagy deficiency in macrophages results in greater silica-induced cytotoxicity. • Autophagy deficiency in macrophages increases extracellular IL-18 and HMGB1.

  12. Chronic oral exposure to the aldehyde pollutant acrolein induces dilated cardiomyopathy

    Science.gov (United States)

    Ismahil, Mohamed Ameen; Hamid, Tariq; Haberzettl, Petra; Gu, Yan; Chandrasekar, Bysani; Srivastava, Sanjay; Bhatnagar, Aruni

    2011-01-01

    Environmental triggers of dilated cardiomyopathy are poorly understood. Acute exposure to acrolein, a ubiquitous aldehyde pollutant, impairs cardiac function and cardioprotective responses in mice. Here, we tested the hypothesis that chronic oral exposure to acrolein induces inflammation and cardiomyopathy. C57BL/6 mice were gavage-fed acrolein (1 mg/kg) or water (vehicle) daily for 48 days. The dose was chosen based on estimates of human daily unsaturated aldehyde consumption. Compared with vehicle-fed mice, acrolein-fed mice exhibited significant (P acrolein adduct formation indicative of physical translocation of ingested acrolein to the heart. Acrolein also induced myocyte hypertrophy (∼2.2-fold increased myocyte area, P acrolein-exposed hearts, along with upregulated gene expression of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β. Long-term oral exposure to acrolein, at an amount within the range of human unsaturated aldehyde intake, induces a phenotype of dilated cardiomyopathy in the mouse. Human exposure to acrolein may have analogous effects and raise consideration of an environmental, aldehyde-mediated basis for heart failure. PMID:21908791

  13. Passive heat exposure induced by hot water leg immersion increased oxyhemoglobin in pre-frontal cortex to preserve oxygenation and did not contribute to impaired cognitive functioning

    Science.gov (United States)

    Wijayanto, Titis; Toramoto, Sayo; Tochihara, Yutaka

    2013-07-01

    This study investigated the effects of passive heat exposure on pre-frontal cortex oxygenation and cognitive functioning, specifically to examine whether the change in pre-frontal cortex oxygenation coincided with cognitive functioning during heat exposure. Eleven male students who participated in this study immersed their lower legs to the knees in three different water temperatures, 38 °C, 40 °C, and 42 °C water in an air temperature of 28 º C and 50 % relative humidity for 60 min. After 45 min of leg immersion they performed cognitive functioning tasks assessing their short-term memory while immersing their lower legs. There were higher rectal temperature ( P 0.05). No statistical difference in cognitive functioning among the three conditions was observed with a higher increase of oxyhemoglobin during the cognitive functioning in the 42 °C condition for the left ( P = 0.05) and right ( P thermally comfortable.

  14. Chronic intermittent ethanol exposure during adolescence: effects on social behavior and ethanol sensitivity in adulthood.

    Science.gov (United States)

    Varlinskaya, Elena I; Truxell, Eric; Spear, Linda P

    2014-08-01

    This study assessed long-lasting consequences of repeated ethanol exposure during two different periods of adolescence on 1) baseline levels of social investigation, play fighting, and social preference and 2) sensitivity to the social consequences of acute ethanol challenge. Adult male and female Sprague-Dawley rats were tested 25 days after repeated exposure to ethanol (3.5 g/kg intragastrically [i.g.], every other day for a total of 11 exposures) in a modified social interaction test. Early-mid adolescent intermittent exposure (e-AIE) occurred between postnatal days (P) 25 and 45, whereas late adolescent intermittent exposure (l-AIE) was conducted between P45 and P65. Significant decreases in social investigation and social preference were evident in adult male rats, but not their female counterparts following e-AIE, whereas neither males nor females demonstrated these alterations following l-AIE. In contrast, both e-AIE and l-AIE produced alterations in sensitivity to acute ethanol challenge in males tested 25 days after adolescent exposure. Ethanol-induced facilitation of social investigation and play fighting, reminiscent of that normally seen during adolescence, was evident in adult males after e-AIE, whereas control males showed an age-typical inhibition of social behavior. Males after l-AIE were found to be insensitive to the socially suppressing effects of acute ethanol challenge, suggesting the development of chronic tolerance in these animals. In contrast, females showed little evidence for alterations in sensitivity to acute ethanol challenge following either early or late AIE. The results of the present study demonstrate a particular vulnerability of young adolescent males to long-lasting detrimental effects of repeated ethanol. Retention of adolescent-typical sensitivity to the socially facilitating effects of ethanol could potentially make ethanol especially appealing to these males, therefore promoting relatively high levels of ethanol intake later

  15. PASSIVE CAVITATION DETECTION DURING PULSED HIFU EXPOSURES OF EX VIVO TISSUES AND IN VIVO MOUSE PANCREATIC TUMORS

    OpenAIRE

    Li, Tong; Chen, Hong; Khokhlova, Tatiana; Wang, Yak-Nam; Kreider, Wayne; He, Xuemei; Hwang, Joo Ha

    2014-01-01

    Pulsed high-intensity focused ultrasound (pHIFU) has been demonstrated to enhance vascular permeability, disrupt tumor barriers and enhance drug penetration into tumor tissue through acoustic cavitation. Monitoring of cavitation activity during pHIFU treatments and knowing the ultrasound pressure levels sufficient to reliably induce cavitation in a given tissue are therefore very important. Here, three metrics of cavitation activity induced by pHIFU and evaluated by confocal passive cavitatio...

  16. Toxicity assessment of sodium fluoride in Drosophila melanogaster after chronic sub-lethal exposure.

    Science.gov (United States)

    Dutta, Moumita; Rajak, Prem; Khatun, Salma; Roy, Sumedha

    2017-01-01

    Sodium fluoride (NaF), one of the most frequently used fluoride compound is composed of Na + and F - . Apart from its use in water fluoridation, NaF also acts as a major component for different dental products like toothpastes, gels and mouth rinses etc. The present study was carried out to explore the toxic impact of chronic NaF exposure on a non-target organism, Drosophila melanogaster. The larvae exposed to different concentrations of NaF through food showed a significant increase in HSP70 expression both qualitatively and quantitatively. The altered tail length and tail intensity in Comet assay validate the increased DNA damage in treated larvae. The activity of AChE, oxidative stress marker enzymes, phase I and phase II detoxifying enzymes were found to be significantly inhibited in the treated larvae when compared to control though there was no evidence of dose dependent change in each case. The alterations in the mentioned parameters can be due to increased body Fluoride ion (F - ) concentration since the analysis with ion electrode analyzer revealed that F - concentration increased significantly with NaF treatment. Hence, the results suggest that D. melanogaster manifest prominent toxic response when subjected to chronic exposure to sub-lethal NaF concentrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. [Behavioral-cognitive disorders due to chronic exposure to industrial and environmental toxic substances].

    Science.gov (United States)

    Mangone, Carlos A; Genovese, Osvaldo; Abel, Carlos

    2006-01-01

    A review of neurotoxics is made, given the low tendency to investigate for chronic exposure to environmental and industrial potential central nervous system toxic substances (heavy metals, insecticides, organic solvents and carbon monoxide) in the history of a patient consulting for behavioral - cognitive complains, and considering the potential overturn of the disease if a correct diagnosis and early treatment is made. to determine the onset of the cognitive - behavioral features, presentation pattern, diagnosis and treatment of such neurotoxics (NT). systematized search in Cochrane and Medline reviews, Embase and Lilacs. chronic exposure to neurotoxics can produce personality changes (sleeping problems, excitation, depression, delusions and hallucinations) as well as cognitive problems (memory, learning, language and cognitive reaction problems). NT may cause changes in the neuron morphology and its sub cellular structures, affecting its normal biochemistry and physiology (proteins and neurotransmitters synthesis). The clinical history, diagnosis and treatment of each neurotoxic are discussed. The NT must be taken in consideration among the possible different etiologies when a patient with a bizarre behavioral cognitive syndrome is examined.

  18. Altered social cognition in male BDNF heterozygous mice and following chronic methamphetamine exposure.

    Science.gov (United States)

    Manning, Elizabeth E; van den Buuse, Maarten

    2016-05-15

    Growing clinical evidence suggests that persistent psychosis which occurs in methamphetamine users is closely related to schizophrenia. However, preclinical studies in animal models have focussed on psychosis-related behaviours following methamphetamine, and less work has been done to assess endophenotypes relevant to other deficits observed in schizophrenia. Altered social behaviour is a feature of both the negative symptoms and cognitive deficits in schizophrenia, and significantly impacts patient functioning. We recently found that brain-derived neurotrophic factor (BDNF) heterozygous mice show disrupted sensitization to methamphetamine, supporting other work suggesting an important role of this neurotrophin in the pathophysiology of psychosis and the neuronal response to stimulant drugs. In the current study, we assessed social and cognitive behaviours in methamphetamine-treated BDNF heterozygous mice and wildtype littermate controls. Following chronic methamphetamine exposure male wildtype mice showed a 50% reduction in social novelty preference. Vehicle-treated male BDNF heterozygous mice showed a similar impairment in social novelty preference, with a trend for no further disruption by methamphetamine exposure. Female mice were unaffected in this task, and no groups showed any changes in sociability or short-term spatial memory. These findings suggest that chronic methamphetamine alters behaviour relevant to disruption of social cognition in schizophrenia, supporting other studies which demonstrate a close resemblance between persistent methamphetamine psychosis and schizophrenia. Together these findings suggest that dynamic regulation of BDNF signalling is necessary to mediate the effects of methamphetamine on behaviours relevant to schizophrenia. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Sub-chronic exposure to paraoxon neither induces nor exacerbates diabetes mellitus in Wistar rat.

    Science.gov (United States)

    Nurulain, Syed M; Petroianu, Georg; Shafiullah, Mohamed; Kalász, Huba; Oz, Murat; Saeed, Tariq; Adem, Abdu; Adeghate, Ernest

    2013-10-01

    There is an increasing belief that organophosphorus compounds (OPCs) impair glucose homeostasis and cause hyperglycemia and diabetes mellitus. The present study was undertaken to investigate the putative diabetogenic effect of sub-lethal and sub-chronic exposure to paraoxon (POX), an extremely hazardous OPC used in pesticides. The effect of paraoxon on streptozotocin-induced diabetic rats was also examined. Each rat was injected with 100 nmol of POX 5 days per week for 6 weeks. Blood glucose levels and red blood cell acetylcholinesterase activity were measured weekly. Biochemical analysis and morphological studies were performed at the end of the experiment. The results revealed that POX neither induces nor exacerbates diabetes mellitus in experimental rats. Liver and kidney/body weight ratios revealed statistically insignificant differences when compared with controls. Biochemical analysis of urine samples showed a small but not significant increase in protein level in all groups. Urine bilirubin was significantly higher in the diabetes + POX group when compared with the control group. The number of blood cells in urine was significantly higher in the POX-treated group compared with the control group. Hyperglycemia was noted in the diabetes and diabetes + POX groups, but neither in the saline control nor in POX-treated normal rats. Electron microscopy of POX-treated pancreas did not show any morphological changes in beta cells. These results suggest that POX does not cause diabetes mellitus at sub-lethal sub-chronic exposure. Copyright © 2012 John Wiley & Sons, Ltd.

  20. Regulation of ex vivo tyrosine hydroxylase (TH) activity is not altered by chronic lead (Pb) exposure

    International Nuclear Information System (INIS)

    Lasley, S.M.; Green, M.C.

    1991-01-01

    Previous studies have suggested that chronic Pb exposure results in impaired regulation of CNS dopamine (DA) synthesis in rats. The present study was designed to directly assess TH activity in exposed animals compared to controls, employing a pharmacological model that assesses the functional status of dopaminergic synthesis-modulating autoreceptors. At birth dams received 0.2% Pb acetate in drinking water. Offspring were weaned to and maintained on the same solution until termination at 60 or 120 days. Rats were given saline or a DA agonist (EMD 23448 or CGS 15855A) 45 min before sacrifice followed 15 min later by gamma-butyrolactone (GBL). Regional TH activity was measured by a modification of the tritium release method. DA content was determined by liquid chromatography. The ability of EMD 23448 to prevent the GBL-induced increase in DA content was significantly diminished in caudate-putamen (C-P) of exposed rats compared to controls, similar to previous observations. However, an analogous effect of Pb on TH activity in this drug model was not observed using CGS 15855A in rats either 60 or 120 days of age. These findings suggest that chronic Pb exposure has no effect on autoreceptor-mediated regulation of TH in DA neurons when TH activity is measured ex vivo

  1. Chronic intermittent exposure to ayahuasca during aging does not affect memory in mice

    Directory of Open Access Journals (Sweden)

    N.F. Correa-Netto

    Full Text Available The Quechua term ayahuasca refers to a beverage obtained from decoctions of the liana Banisteriopsis caapi with leaves of Psychotria viridis. The ritualistic use of ayahuasca is becoming a global phenomenon, with some individuals using this beverage throughout life, including in old age. Cognitive impairment is a common manifestation during aging. There are conflicting reports on the ability of some ayahuasca compounds to exert neuroprotective or neurotoxic effects that could improve or impair learning and memory. Animal models provide a relevant and accessible means of investigating the behavioral effects of ayahuasca without the environmental conditions associated with the ritualistic use of the beverage. In this study, we investigated the influence of chronic ayahuasca exposure throughout aging on the spatial reference and habituation memories of mice. Twenty-eight male c57bl/6 mice (6 months old received ayahuasca or water (1.5 mL/kg, orally twice a week for 12 months and were tested in the Morris water maze (MWM, open field and elevated plus maze (EPM tasks before and after treatment. During aging, there was significant impairment in the evocation (but not acquisition of spatial reference memory and in habituation to the open field. There was also a decrease in locomotor activity in the open field and EPM tests, whereas the anxiety parameters were unaltered. Ayahuasca treatment did not alter any of these parameters associated with aging. These findings indicate that chronic exposure to ayahuasca during aging did not affect memory in mice.

  2. Chronic intermittent exposure to ayahuasca during aging does not affect memory in mice.

    Science.gov (United States)

    Correa-Netto, N F; Coelho, L S; Galfano, G S; Nishide, F; Tamura, F; Shimizu, M K; Santos, J G; Linardi, A

    2017-06-05

    The Quechua term ayahuasca refers to a beverage obtained from decoctions of the liana Banisteriopsis caapi with leaves of Psychotria viridis. The ritualistic use of ayahuasca is becoming a global phenomenon, with some individuals using this beverage throughout life, including in old age. Cognitive impairment is a common manifestation during aging. There are conflicting reports on the ability of some ayahuasca compounds to exert neuroprotective or neurotoxic effects that could improve or impair learning and memory. Animal models provide a relevant and accessible means of investigating the behavioral effects of ayahuasca without the environmental conditions associated with the ritualistic use of the beverage. In this study, we investigated the influence of chronic ayahuasca exposure throughout aging on the spatial reference and habituation memories of mice. Twenty-eight male c57bl/6 mice (6 months old) received ayahuasca or water (1.5 mL/kg, orally) twice a week for 12 months and were tested in the Morris water maze (MWM), open field and elevated plus maze (EPM) tasks before and after treatment. During aging, there was significant impairment in the evocation (but not acquisition) of spatial reference memory and in habituation to the open field. There was also a decrease in locomotor activity in the open field and EPM tests, whereas the anxiety parameters were unaltered. Ayahuasca treatment did not alter any of these parameters associated with aging. These findings indicate that chronic exposure to ayahuasca during aging did not affect memory in mice.

  3. Development of Toxicological Risk Assessment Models for Acute and Chronic Exposure to Pollutants

    Directory of Open Access Journals (Sweden)

    Elke S. Reichwaldt

    2016-08-01

    Full Text Available Alert level frameworks advise agencies on a sequence of monitoring and management actions, and are implemented so as to reduce the risk of the public coming into contact with hazardous substances. Their effectiveness relies on the detection of the hazard, but with many systems not receiving any regular monitoring, pollution events often go undetected. We developed toxicological risk assessment models for acute and chronic exposure to pollutants that incorporate the probabilities that the public will come into contact with undetected pollution events, to identify the level of risk a system poses in regards to the pollutant. As a proof of concept, we successfully demonstrated that the models could be applied to determine probabilities of acute and chronic illness types related to recreational activities in waterbodies containing cyanotoxins. Using the acute model, we identified lakes that present a ‘high’ risk to develop Day Away From Work illness, and lakes that present a ‘low’ or ‘medium’ risk to develop First Aid Cases when used for swimming. The developed risk models succeeded in categorising lakes according to their risk level to the public in an objective way. Modelling by how much the probability of public exposure has to decrease to lower the risks to acceptable levels will enable authorities to identify suitable control measures and monitoring strategies. We suggest broadening the application of these models to other contaminants.

  4. Chronic Oral Capsaicin Exposure During Development Leads to Adult Rats with Reduced Taste Bud Volumes.

    Science.gov (United States)

    Omelian, Jacquelyn M; Samson, Kaeli K; Sollars, Suzanne I

    2016-09-01

    Cross-sensory interaction between gustatory and trigeminal nerves occurs in the anterior tongue. Surgical manipulations have demonstrated that the strength of this relationship varies across development. Capsaicin is a neurotoxin that affects fibers of the somatosensory lingual nerve surrounding taste buds, but not fibers of the gustatory chorda tympani nerve which synapse with taste receptor cells. Since capsaicin is commonly consumed by many species, including humans, experimental use of this neurotoxin provides a naturalistic perturbation of the lingual trigeminal system. Neonatal or adults rats consumed oral capsaicin for 40 days and we examined the cross-sensory effect on the morphology of taste buds across development. Rats received moderate doses of oral capsaicin, with chronic treatments occurring either before or after taste system maturation. Tongue morphology was examined either 2 or 50 days after treatment cessation. Edema, which has been previously suggested as a cause of changes in capsaicin-related gustatory function, was also assessed. Reductions in taste bud volume occurred 50 days, but not 2 days post-treatment for rats treated as neonates. Adult rats at either time post-treatment were unaffected. Edema was not found to occur with the 5 ppm concentration of capsaicin we used. Results further elucidate the cooperative relationship between these discrete sensory systems and highlight the developmentally mediated aspect of this interaction. Chronic exposure to even moderate levels of noxious stimuli during development has the ability to impact the orosensory environment, and these changes may not be evident until long after exposure has ceased.

  5. Chronic exposure of zinc oxide nanoparticles causes deviant phenotype in Drosophila melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Anand, Avnika Singh; Prasad, Dipti N.; Singh, Shashi Bala; Kohli, Ekta, E-mail: ektakohli@hotmail.com

    2017-04-05

    Zinc oxide nanoparticles (ZnO NPs) are commonly used nanomaterials (NMs) with versatile applications from high-end technologies to household products. This pervasive utilisation has brought human in the close interface with nanoparticles (NPs), hence questioning their safety prior to usage is a must. In this study, we have assessed the effects of chronic exposure to ZnO NPs (<50 nm) on the model organism Drosophila melanogaster. Potential toxic effects were studied by evaluating longevity, climbing ability, oxidative stress and DNA fragmentation. Ensuing exposure, the F0 (parent), F1, F2, F3 and F4 generation flies were screened for the aberrant phenotype. Flies exposed to ZnO NPs showed distinctive phenotypic changes, like deformed segmented thorax and single or deformed wing, which were transmitted to the offspring’s in subsequent generations. The unique abnormal phenotype is evident of chronic toxicity induced by ZnO NPs, although appalling, it strongly emphasize the importance to understand NPs toxicity for safer use.

  6. Persistence of DNA damage following exposure of human bladder cells to chronic monomethylarsonous acid

    International Nuclear Information System (INIS)

    Wnek, S.M.; Medeiros, M.K.; Eblin, K.E.; Gandolfi, A.J.

    2009-01-01

    Malignant transformation was demonstrated in UROtsa cells following 52-weeks of exposure to 50 nM monomethylarsonous acid (MMA III ); the result was the malignantly transformed cell line, URO-MSC. URO-MSC cells were used to study the induction of DNA damage and the alteration of DNA repair enzymes in both the presence of MMA III [URO-MSC(+)] and after subsequent removal of MMA III [URO-MSC(-)] following chronic, low-level exposure. In the presence of MMA III , URO-MSC(+) cells demonstrated a sustained increase in DNA damage following 12-weeks of exposure; in particular, a significant increase in DNA single-strand breaks at 12-weeks of exposure consistently elevated through 52 weeks. The persistence of DNA damage in URO-MSC cells was assessed after a 2-week removal of MMA III . URO-MSC(-) cells demonstrated a decrease in DNA damage compared to URO-MSC(+); however, DNA damage in URO-MSC(-) remained significantly elevated when compared to untreated UROtsa and increased in a time-dependent manner. Reactive oxygen species (ROS) were demonstrated to be a critical component in the generation of DNA damage determined through the incubation of ROS scavengers with URO-MSC cells. Poly (ADP-ribose) polymerase (PARP) is a key repair enzyme in DNA single-strand break repair. URO-MSC(+) resulted in a slight increase in PARP activity after 36-weeks of MMA III exposure, suggesting the presence of MMA III is inhibiting the increase in PARP activity. In support, PARP activity in URO-MSC(-) increased significantly, coinciding with a subsequent decrease in DNA damage demonstrated in URO-MSC(-) compared to URO-MSC(+). These data demonstrate that chronic, low-level exposure of UROtsa cells to 50 nM MMA III results in: the induction of DNA damage that remains elevated upon removal of MMA III ; increased levels of ROS that play a role in MMA III induced-DNA damage; and decreased PARP activity in the presence of MMA III .

  7. Passive safety; Passive Sicherheit

    Energy Technology Data Exchange (ETDEWEB)

    Rueckert, J. [Skoda Auto a.s., Mlada Boleslav (Czech Republic). Interieurentwicklung und Versuche; Hau, M. [Skoda Auto a.s., Mlada Boleslav (Czech Republic). Koordination der Fahrzeugsicherung

    2004-05-01

    The specifications for passive safety are partly based on the legal requirements for all export markets combined with the strict internal standards of Volkswagen Group. The Euro NCAP tests and their precisely defined testing methods using the new point assessment are very important. (orig.)

  8. Neurobehavioral impairments, generation of oxidative stress and release of pro-apoptotic factors after chronic exposure to sulphur mustard in mouse brain

    International Nuclear Information System (INIS)

    Sharma, Deep Raj; Sunkaria, Aditya; Bal, Amanjit; Bhutia, Yangchen D.; Vijayaraghavan, R.; Flora, S.J.S.; Gill, Kiran Dip

    2009-01-01

    Recent global events have focused attention on the potential threat of international and domestic chemical terrorism, as well as the possibility of chemical warfare proliferation. Sulphur mustard (SM) is one of the potent chemical warfare agents (CWA), which initiates a cascade of events that converge on the redox mechanisms common to brain injury. The present study was designed to examine the effects of chronic SM exposure on neurobehavioral impairments, mitochondrial oxidative stress in male Swiss Albino mice and its role in inducing apoptotic neuronal cell death. The animals were divided into four groups (control, low, medium and high dose) of 5 animals each. Exposure to SM was given percutaneously daily for 12 weeks. The results demonstrated impairment in neurobehavioral indices viz. rota rod, passive avoidance and water maze tests in a dose dependent manner. There was a significant increase in lipid peroxidation and protein carbonyl content whereas, decrease in the activity of manganese superoxide dismutase (MnSOD), glutathione reductase and glutathione peroxidase suggesting impaired antioxidant defense system. Immunoblotting of cytochrome c, Bcl-2, Bax and activation of caspase-3 suggest induction of apoptosis in a dose dependent manner. Finally, increased p53 expression suggests that it may target the mitochondrial pathway for inducing apoptosis in response to DNA damage signals. In conclusion, chronic SM exposure may have the potential to generate oxidative stress which may trigger the release of cytochrome c as well as caspase-3 activation in neurons leading to cell death by apoptosis in a dose dependent manner which may in the end be responsible for the disruption of cognitive functions in mice.

  9. Health effect of chronic exposure to carbon disulfide (CS 2 on women employed in viscose industry

    Directory of Open Access Journals (Sweden)

    Krzysztof Sieja

    2018-05-01

    Full Text Available Many women are exposed to carbon disulfide (CS 2 hazards at work every day. Working with CS 2 may cause some women to experience abnormalities in their reproductive health. Until now obtained data is generally concentrated on the health effects of CS 2 observed in the viscose industry. To date, CS 2 has not been studied precisely for its potential to have damaging effects on female reproductive system, especially the frequency of menstrual disturbances and the course of menopause. The aim of the study was to sum up female reproductive health hazards amongst women chronically exposed to CS 2 in their workplace in the viscose industry. In order to study the effect of CS 2 in the contemporary viscose industry, exposure measurements should be collected in prospective or cross-sectional studies. In conclusion, reproductive health hazards for women chronically exposed to CS 2 in the workplace in the viscose industry are the following: 1 menstrual disorders essentially are more frequent than in the case of the healthy women, 2 for women chronically exposed to CS 2 the average menopausal age is statistically earlier, as compared to healthy women, 3 complex disturbances in neurohormonal system for women exposed to CS 2 , resulting from toxic influences of CS 2 , which cause the secretion of estrogens and progesterone in ovaries and dehydroepiandrosterone sulfate in the adrenal gland to diminish. Med Pr 2018;69(3:329–335

  10. Effects of Chronic Exposure to Sodium Arsenate on Kidney of Rats

    Directory of Open Access Journals (Sweden)

    Namdar Yousofvand

    2015-09-01

    Full Text Available Background: In the present study, histopathological effects of chronic exposure to sodium arsenate in drinkable water were studied on a quantity of organs of rat. Methods: Rats were divided into two groups, group I; served as control group, were main-tained on deionized drinkable water for 2 months, and group II; the study group were given 60 g/ml of sodium arsenate in deionized drinkable water for 2 months. Blood and urine samples from two groups of animals were collected under anesthesia and the animals were sacrificed under deep anesthesia (a-chloralose, 100 mg/kg, I.P. Their kidney, liver, aorta, and heart were dissected out and cleaned of surrounding connective tissue. The organs were kept in formaldehyde (10% for histopathologic examination. Serum and urine samples from two groups were collected and analyzed for arsenic level. Total quantity of arsenic in serum and urine of animal was measured through graphic furnace atomic absorption spectrometry (GF-AAS. Results:Examination with light microscopy did not show any visible structural changes in the aorta, myocardium, and liver of chronic arsenic treated animals.However, a significant effect was observed in the kidneys of chronic arsenic treated rats showing distinct changes in proxi-mal tubular cells. There was high concentration of arsenic in serum and urine of arsenic ex-posed animals (group II significantly (P<0.001. Conclusion:Swollen tubular cells in histopathologic study of kidney may suggest toxic effects of arsenic in the body.

  11. Effect of chronic exposure to aspartame on oxidative stress in the brain of albino rats.

    Science.gov (United States)

    Iyyaswamy, Ashok; Rathinasamy, Sheeladevi

    2012-09-01

    This study was aimed at investigating the chronic effect of the artificial sweetener aspartame on oxidative stress in brain regions of Wistar strain albino rats. Many controversial reports are available on the use of aspartame as it releases methanol as one of its metabolite during metabolism. The present study proposed to investigate whether chronic aspartame (75 mg/kg) administration could release methanol and induce oxidative stress in the rat brain. To mimic the human methanol metabolism, methotrexate (MTX)-treated rats were included to study the aspartame effects. Wistar strain male albino rats were administered with aspartame orally and studied along with controls and MTX-treated controls. The blood methanol level was estimated, the animal was sacrificed and the free radical changes were observed in brain discrete regions by assessing the scavenging enzymes, reduced glutathione, lipid peroxidation (LPO) and protein thiol levels. It was observed that there was a significant increase in LPO levels, superoxide dismutase (SOD) activity, GPx levels and CAT activity with a significant decrease in GSH and protein thiol. Moreover, the increases in some of these enzymes were region specific. Chronic exposure of aspartame resulted in detectable methanol in blood. Methanol per se and its metabolites may be responsible for the generation of oxidative stress in brain regions.

  12. Expression of blood serum proteins and lymphocyte differentiation clusters after chronic occupational exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rybkina, Valentina L.; Azizova, Tamara V.; Adamova, Galina V.; Teplyakova, Olga V.; Osovets, Sergey V.; Bannikova, Maria V. [Southern Urals Biophysics Institute, Ozyorsk, Chelyabinsk Region (Russian Federation); Scherthan, Harry; Meineke, Viktor; Doerr, Harald [University of Ulm, Bundeswehr Institute of Radiobiology, Munich (Germany); Zurochka, Alexander V. [Immunology Institute, Yekaterinburg (Russian Federation)

    2014-11-15

    This study aimed to assess effects of chronic occupational exposure on immune status in Mayak workers chronically exposed to ionizing radiation (IR). The study cohort consists of 77 workers occupationally exposed to external gamma-rays at total dose from 0.5 to 3.0 Gy (14 individuals) and workers with combined exposure (external gamma-rays at total dose range 0.7-5.1 Gy and internal alpha-radiation from incorporated plutonium with a body burden of 0.3-16.4 kBq). The control group consists of 43 age- and sex-matched individuals who never were exposed to IR, never involved in any cleanup operations following radiation accidents and never resided at contaminated areas. Enzyme-linked immunoassay and flow cytometry were used to determine the relative concentration of lymphocytes and proteins. The concentrations of T-lymphocytes, interleukin-8 and immunoglobulins G were decreased in external gamma-exposed workers relative to control. Relative concentrations of NKT-lymphocytes, concentrations of transforming growth factor-β, interferon gamma, immunoglobulins A, immunoglobulins M and matrix proteinase-9 were higher in this group as compared with control. Relative concentrations of T-lymphocytes and concentration of interleukin-8 were decreased, while both the relative and absolute concentration of natural killers, concentration of immunoglobulins A and M and matrix proteinase-9 were increased in workers with combined exposure as compared to control. An inverse linear relation was revealed between absolute concentration of T-lymphocytes, relative and absolute concentration of T-helpers cells, concentration of interferon gamma and total absorbed dose from external gamma-rays in exposed workers. For workers with incorporated plutonium, there was an inverse linear relation of absolute concentration of T-helpers as well as direct linear relation of relative concentration of NKT-lymphocytes to total absorbed red bone marrow dose from internal alpha-radiation. In all, chronic

  13. Expression of blood serum proteins and lymphocyte differentiation clusters after chronic occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Rybkina, Valentina L.; Azizova, Tamara V.; Adamova, Galina V.; Teplyakova, Olga V.; Osovets, Sergey V.; Bannikova, Maria V.; Scherthan, Harry; Meineke, Viktor; Doerr, Harald; Zurochka, Alexander V.

    2014-01-01

    This study aimed to assess effects of chronic occupational exposure on immune status in Mayak workers chronically exposed to ionizing radiation (IR). The study cohort consists of 77 workers occupationally exposed to external gamma-rays at total dose from 0.5 to 3.0 Gy (14 individuals) and workers with combined exposure (external gamma-rays at total dose range 0.7-5.1 Gy and internal alpha-radiation from incorporated plutonium with a body burden of 0.3-16.4 kBq). The control group consists of 43 age- and sex-matched individuals who never were exposed to IR, never involved in any cleanup operations following radiation accidents and never resided at contaminated areas. Enzyme-linked immunoassay and flow cytometry were used to determine the relative concentration of lymphocytes and proteins. The concentrations of T-lymphocytes, interleukin-8 and immunoglobulins G were decreased in external gamma-exposed workers relative to control. Relative concentrations of NKT-lymphocytes, concentrations of transforming growth factor-β, interferon gamma, immunoglobulins A, immunoglobulins M and matrix proteinase-9 were higher in this group as compared with control. Relative concentrations of T-lymphocytes and concentration of interleukin-8 were decreased, while both the relative and absolute concentration of natural killers, concentration of immunoglobulins A and M and matrix proteinase-9 were increased in workers with combined exposure as compared to control. An inverse linear relation was revealed between absolute concentration of T-lymphocytes, relative and absolute concentration of T-helpers cells, concentration of interferon gamma and total absorbed dose from external gamma-rays in exposed workers. For workers with incorporated plutonium, there was an inverse linear relation of absolute concentration of T-helpers as well as direct linear relation of relative concentration of NKT-lymphocytes to total absorbed red bone marrow dose from internal alpha-radiation. In all, chronic

  14. Acute vs chronic exposure to high fat diet leads to distinct regulation of PKA.

    Science.gov (United States)

    London, Edra; Nesterova, Maria; Stratakis, Constantine A

    2017-07-01

    The cAMP-dependent protein kinase (PKA) is an essential regulator of lipid and glucose metabolism that plays a critical role in energy homeostasis. The impact of diet on PKA signaling has not been defined, although perturbations in individual PKA subunits are associated with changes in adiposity, physical activity and energy intake in mice and humans. We hypothesized that a high fat diet (HFD) would elicit peripheral and central alterations in the PKA system that would differ depending on length of exposure to HFD; these differences could protect against or promote diet-induced obesity (DIO). 12-week-old C57Bl/6J mice were randomly assigned to a regular diet or HFD and weighed weekly throughout the feeding studies (4 days, 14 weeks; respectively), and during killing. PKA activity and subunit expression were measured in liver, gonadal adipose tissue (AT) and brain. Acute HFD-feeding suppressed basal hepatic PKA activity. In contrast, hepatic and hypothalamic PKA activities were significantly increased after chronic HFD-feeding. Changes in AT were more subtle, and overall, altered PKA regulation in response to chronic HFD exposure was more profound in female mice. The suppression of hepatic PKA activity after 4 day HFD-feeding was indicative of a protective peripheral effect against obesity in the context of overnutrition. In response to chronic HFD-feeding, and with the development of DIO, dysregulated hepatic and hypothalamic PKA signaling was a signature of obesity that is likely to promote further metabolic dysfunction in mice. © 2017 Society for Endocrinology.

  15. Changes in the α4β2* nicotinic acetylcholine system during chronic controlled alcohol exposure in nonhuman primates.

    Science.gov (United States)

    Hillmer, Ansel T; Tudorascu, Dana L; Wooten, Dustin W; Lao, Patrick J; Barnhart, Todd E; Ahlers, Elizabeth O; Resch, Leslie M; Larson, Julie A; Converse, Alexander K; Moore, Colleen F; Schneider, Mary L; Christian, Bradley T

    2014-05-01

    The precise nature of modifications to the nicotinic acetylcholine receptor (nAChR) system in response to chronic ethanol exposure is poorly understood. The present work used PET imaging to assay α4β2* nAChR binding levels of eight rhesus monkeys before and during controlled chronic ethanol intake. [(18)F]Nifene PET scans were conducted prior to alcohol exposure, and then again after at least 8 months controlled ethanol exposure, including 6 months at 1.5 g/kg/day following a dose escalation period. Receptor binding levels were quantified with binding potentials (BPND) using the cerebellum as a reference region. Alcohol self-administration was assessed as average daily alcohol intake during a 2 month free drinking period immediately following controlled alcohol. Significant decreases in α4β2* nAChR binding were observed in both frontal and insular cortex in response to chronic ethanol exposure. During chronic alcohol exposure, BPND in the lateral geniculate region correlated positively with the amount of alcohol consumed during free drinking. The observed decreases in nAChR availability following chronic alcohol consumption suggest alterations to this receptor system in response to repeated alcohol administration, making this an important target for further study in alcohol abuse and alcohol and nicotine codependence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Metallothionein (MT) response after chronic palladium exposure in the zebra mussel, Dreissena polymorpha

    International Nuclear Information System (INIS)

    Frank, Sabrina N.; Singer, Christoph; Sures, Bernd

    2008-01-01

    The effects of different exposure concentrations of palladium (Pd) on relative metallothionein (MT) response and bioaccumulation were investigated in zebra mussels (Dreissena polymorpha). The mussels were exposed to 0.05, 5, 50, and 500 μg/L Pd 2+ for 10 weeks under controlled temperature and fasting conditions. Relative MT contents were assessed by a modified Ag-saturation method, which allows to discriminate between MT bound to Pd (Pd-MT) and MT bound to unidentified metals (Ag-MT). Determination of metal contents resulted from atomic absorption spectrometry following a microwave digestion. For unexposed mussels and mussels exposed to 0.05 μg/L Pd no metal accumulation could be detected. All other exposure concentrations resulted in detectable Pd accumulation in mussels with final tissue concentrations of 96 μg/g (500 μg/L), 45 μg/g (50 μg/L), and 9 μg/g (5 μg/L). Compared with initial levels Pd-MT concentrations at the end of the exposure period were 600 (500 μg/L), 160 (50 μg/L), and 27 (5 μg/L) times higher. These results show that an increase in MTs in D. polymorpha already occurs at relatively low aqueous Pd concentrations indicating that there is the need for detoxification of Pd in the mussel. Furthermore, correlations between Ag-MT and Pd accumulation indicate that higher exposure concentrations are associated with adverse effects on the mussels. Thus, harmful effects of chronic Pd exposure of organisms even in lowest concentrations cannot be excluded in the environment

  17. Chronic subhepatotoxic exposure to arsenic enhances hepatic injury caused by high fat diet in mice

    International Nuclear Information System (INIS)

    Tan, Min; Schmidt, Robin H.; Beier, Juliane I.; Watson, Walter H.; Zhong, Hai; States, J. Christopher; Arteel, Gavin E.

    2011-01-01

    Arsenic is a ubiquitous contaminant in drinking water. Whereas arsenic can be directly hepatotoxic, the concentrations/doses required are generally higher than present in the US water supply. However, physiological/biochemical changes that are alone pathologically inert can enhance the hepatotoxic response to a subsequent stimulus. Such a ‘2-hit’ paradigm is best exemplified in chronic fatty liver diseases. Here, the hypothesis that low arsenic exposure sensitizes liver to hepatotoxicity in a mouse model of non-alcoholic fatty liver disease was tested. Accordingly, male C57Bl/6J mice were exposed to low fat diet (LFD; 13% calories as fat) or high fat diet (HFD; 42% calories as fat) and tap water or arsenic (4.9 ppm as sodium arsenite) for ten weeks. Biochemical and histologic indices of liver damage were determined. High fat diet (± arsenic) significantly increased body weight gain in mice compared with low-fat controls. HFD significantly increased liver to body weight ratios; this variable was unaffected by arsenic exposure. HFD caused steatohepatitis, as indicated by histological assessment and by increases in plasma ALT and AST. Although arsenic exposure had no effect on indices of liver damage in LFD-fed animals, it significantly increased the liver damage caused by HFD. This effect of arsenic correlated with enhanced inflammation and fibrin extracellular matrix (ECM) deposition. These data indicate that subhepatotoxic arsenic exposure enhances the toxicity of HFD. These results also suggest that arsenic exposure might be a risk factor for the development of fatty liver disease in human populations. -- Highlights: ► Characterizes a mouse model of arsenic enhanced NAFLD. ► Arsenic synergistically enhances experimental fatty liver disease at concentrations that cause no overt hepatotoxicity alone. ► This effect is associated with increased inflammation.

  18. Decision-making about chronic radiation exposure to the public. New recommendations from the ICRP

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, A.J. [Division of Radiation and Waste Safety, International Atomic Energy Agency, Vienna (Austria)

    2000-05-01

    The paper discusses decision-making in situations of chronic exposure within the framework of a forthcoming related ICRP report on the subject which has been produced by an ICRP Task Group chaired by the author. This ICRP report will provide guidance on the application of the ICRP System of Radiological Protection to prolonged exposure situations afflicting members of the public. It will address the general application of the System to the control of prolonged exposures resulting from practices and to the undertaking of interventions in prolonged exposure situations, and will provide recommendations on generic reference levels for such interventions. It will also consider some specific situations and will discuss a number of issues that have been of concern, namely: natural radiation sources that may give rise to high doses; the restoration and rehabilitation of sites where human activities involving radioactive substances have been carried out; the return to 'normality' following an accident that has released radioactive substances to the environment; and the global marketing of commodities for public consumption that contain relatively high levels of radioactive substances. Annexes will provide some examples of prolonged exposure situations and will discuss the radiological protection quantities, radiation-induced health effects and aspects of the System of Radiological Protection relevant to prolonged exposure. The quantitative recommendations for prolonged exposures provided in the report will be as follows: generic reference levels for intervention, in terms of existing annual doses, of < or approx. 100 mSv, above which intervention is almost always justifiable (situations for which the annual dose threshold for deterministic effects in relevant organs is exceeded will almost always require intervention), and of < or approx.10 mSv, below which intervention is not likely to be justifiable (and above which it may be necessary); intervention exemption

  19. Limb regeneration and molting processes under chronic methoprene exposure in the mud fiddler crab, Uca pugnax.

    Science.gov (United States)

    Stueckle, Todd A; Likens, Jason; Foran, Christy M

    2008-04-01

    Insect growth regulator application for wetland mosquito control remains controversial due to the potential for disruption of normal development and growth processes in non-target crustaceans and beneficial arthropods, e.g. Apis mellifera. Concerns include slow-release methoprene formulations and its environmental breakdown products which mimic an endogenous crustacean hormone and retinoids, respectively. Our primary objective was to evaluate the effect that a chronic methoprene exposure would have on male and female Uca pugnax limb regeneration and molting. After single limb autonomy, limb growth and molt stage were monitored every two days while eyestalk ablation was used to induce proecdysis. Dorsal carapace was collected 6 days post-molt to determine protein and chitin content. In post-molt crabs, methoprene-exposed individuals displayed lower percent gain in body weight. Male crabs lost more weight per body volume than females, took significantly longer to proceed through proecdysis than females exposed to 0.1 microg/L methoprene and exhibited significantly elevated frequency for abnormal limb formation at 1.0 microg/L while females displayed no such trend. Methoprene did not significantly alter extractable exoskeleton protein or chitin content. However, variable water-soluble protein expression increased with exposure at 1.0 microg/L (1 ppb) which contributed to overall variability in total protein content. Our findings suggest that adult male U. pugnax possess greater sensitivity to chronic methoprene exposure during limb regeneration and molting, potentially affecting their post-molt fitness. Furthermore, methoprene has the potential to impact post-molt biomass and exocuticle quality.

  20. Microfluidic gradient device for studying mesothelial cell migration and the effect of chronic carbon nanotube exposure

    International Nuclear Information System (INIS)

    Zhang, Hanyuan; Sun, Jianbo; Li, Xiang; Liu, Yuxin; Lohcharoenkal, Warangkana; Rojanasakul, Yon; Wang, Liying; Wu, Nianqiang

    2015-01-01

    Cell migration is one of the crucial steps in many physiological and pathological processes, including cancer development. Our recent studies have shown that carbon nanotubes (CNTs), similarly to asbestos, can induce accelerated cell growth and invasiveness that contribute to their mesothelioma pathogenicity. Malignant mesothelioma is a very aggressive tumor that develops from cells of the mesothelium, and is most commonly caused by exposure to asbestos. CNTs have a similar structure and mode of exposure to asbestos. This has raised a concern regarding the potential carcinogenicity of CNTs, especially in the pleural area which is a key target for asbestos-related diseases. In this paper, a static microfluidic gradient device was applied to study the migration of human pleural mesothelial cells which had been through a long-term exposure (4 months) to subcytotoxic concentration (0.02 µg cm −2 ) of single-walled CNTs (SWCNTs). Multiple migration signatures of these cells were investigated using the microfluidic gradient device for the first time. During the migration study, we observed that cell morphologies changed from flattened shapes to spindle shapes prior to their migration after their sensing of the chemical gradient. The migration of chronically SWCNT-exposed mesothelial cells was evaluated under different fetal bovine serum (FBS) concentration gradients, and the migration speeds and number of migrating cells were extracted and compared. The results showed that chronically SWCNT-exposed mesothelial cells are more sensitive to the gradient compared to non-SWCNT-exposed cells. The method described here allows simultaneous detection of cell morphology and migration under chemical gradient conditions, and also allows for real-time monitoring of cell motility that resembles in vivo cell migration. This platform would be much needed for supporting the development of more physiologically relevant cell models for better assessment and characterization of the

  1. Microfluidic gradient device for studying mesothelial cell migration and the effect of chronic carbon nanotube exposure

    Science.gov (United States)

    Zhang, Hanyuan; Lohcharoenkal, Warangkana; Sun, Jianbo; Li, Xiang; Wang, Liying; Wu, Nianqiang; Rojanasakul, Yon; Liu, Yuxin

    2015-07-01

    Cell migration is one of the crucial steps in many physiological and pathological processes, including cancer development. Our recent studies have shown that carbon nanotubes (CNTs), similarly to asbestos, can induce accelerated cell growth and invasiveness that contribute to their mesothelioma pathogenicity. Malignant mesothelioma is a very aggressive tumor that develops from cells of the mesothelium, and is most commonly caused by exposure to asbestos. CNTs have a similar structure and mode of exposure to asbestos. This has raised a concern regarding the potential carcinogenicity of CNTs, especially in the pleural area which is a key target for asbestos-related diseases. In this paper, a static microfluidic gradient device was applied to study the migration of human pleural mesothelial cells which had been through a long-term exposure (4 months) to subcytotoxic concentration (0.02 µg cm-2) of single-walled CNTs (SWCNTs). Multiple migration signatures of these cells were investigated using the microfluidic gradient device for the first time. During the migration study, we observed that cell morphologies changed from flattened shapes to spindle shapes prior to their migration after their sensing of the chemical gradient. The migration of chronically SWCNT-exposed mesothelial cells was evaluated under different fetal bovine serum (FBS) concentration gradients, and the migration speeds and number of migrating cells were extracted and compared. The results showed that chronically SWCNT-exposed mesothelial cells are more sensitive to the gradient compared to non-SWCNT-exposed cells. The method described here allows simultaneous detection of cell morphology and migration under chemical gradient conditions, and also allows for real-time monitoring of cell motility that resembles in vivo cell migration. This platform would be much needed for supporting the development of more physiologically relevant cell models for better assessment and characterization of the

  2. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    Science.gov (United States)

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  3. Effects of chronic ammonia exposure on ammonia metabolism and excretion in marine medaka Oryzias melastigma.

    Science.gov (United States)

    Gao, Na; Zhu, Limei; Guo, Zhiqiang; Yi, Meisheng; Zhang, Li

    2017-06-01

    Ammonia is highly toxic to aquatic organisms, but whether ammonia excretion or ammonia metabolism to less toxic compounds is the major strategy for detoxification in marine fish against chronic ammonia exposure is unclear to date. In this study, we investigated the metabolism and excretion of ammonia in marine medaka Oryzias melastigma during chronic ammonia exposure. The fish were exposed to 0, 0.1, 0.3, 0.6, and 1.1 mmol l -1  NH 4 Cl spiked seawater for 8 weeks. Exposure of 0.3-1.1 mmol l -1  NH 4 Cl had deleterious effects on the fish, including significant reductions in growth, feed intake, and total protein content. However, the fish could take strategies to detoxify ammonia. The tissue ammonia (T Amm ) in the 0.3-1.1 mmol l -1  NH 4 Cl treatments was significantly higher than those in the 0 and 0.1 mmol l -1  NH 4 Cl treatments after 2 weeks of exposure, but it recovered with prolonged exposure time, ultimately reaching the control level after 8 weeks. The amino acid catabolic rate decreased to reduce the gross ammonia production with the increasing ambient ammonia concentration. The concentrations of most metabolites remained constant in the 0-0.6 mmol l -1  NH 4 Cl treatments, whereas 5 amino acids and 3 energy metabolism-related metabolites decreased in the 1.1 mmol l -1  NH 4 Cl treatment. J Amm steadily increased in ambient ammonia from 0 to 0.6 mmol l -1 and slightly decreased when the ambient ammonia concentration increased to 1.1 mmol l -1 . Overall, marine medaka cope with sublethal ammonia environment by regulating the tissue T Amm via reducing the ammonia production and increasing ammonia excretion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees

    Science.gov (United States)

    2016-01-01

    Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasite Nosema ceranae slightly impaired learning in honeybees, but no interactive effects were observed. Nosema did not infect bumblebees (3% infection success). Nevertheless, Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. PMID:27053744

  5. Chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees.

    Science.gov (United States)

    Piiroinen, Saija; Goulson, Dave

    2016-04-13

    Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasite Nosema ceranae slightly impaired learning in honeybees, but no interactive effects were observed. Nosema did not infect bumblebees (3% infection success). Nevertheless, Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. © 2016 The Author(s).

  6. Oral exposure to dibutyl phthalate exacerbates chronic lymphocytic thyroiditis through oxidative stress in female Wistar rats.

    Science.gov (United States)

    Wu, Yang; Li, Jinquan; Yan, Biao; Zhu, Yuqing; Liu, Xudong; Chen, Mingqing; Li, Dai; Lee, Ching-Chang; Yang, Xu; Ma, Ping

    2017-11-13

    Chronic lymphocytic thyroiditis (CLT) is a common autoimmune disorder. The possible pathogenic role and mechanism of dibutyl phthalate (DBP) in CLT is still controversial. Experiments were conducted after 35-days of oral exposure to the three concentrations of DBP or saline, and three immunizations with thyroglobulin (TG). Healthy female Wistar rats were randomly divided into ten exposure groups (n = 8 each): (A) saline control, (B) 0.5 mg/kg/d DBP, (C) 5 mg/kg/d DBP, (D) 50 mg/kg/d DBP, (E) TG-immunized group, (F) TG- combined with 0.5 mg/kg/d DBP, (G) TG- combined with 5 mg/kg/d DBP, (H) TG- combined with 50 mg/kg/d DBP, (I) TG- combined with 50 mg/kg/d DBP plus 100 mg/kg/d vitamin C; (J) 100 mg/kg/d vitamin C. We showed that oral exposure DBP can aggravate CLT in rats. This deterioration was concomitant with increased thyroid auto antibodies, Th1/Th2 imbalance and Th17 immune response, activated pro-inflammatory and apoptosis pathways, and increased thyroid dysfunction in rats. Our results also suggested that DBP could promote oxidative damage. The study also found that vitamin C reduced the levels of oxidative stress and alleviated CLT. In short, the study showed that DBP exacerbated CLT through oxidative stress.

  7. Effects of chronic exposure to electromagnetic waves on the auditory system.

    Science.gov (United States)

    Özgür, Abdulkadir; Tümkaya, Levent; Terzi, Suat; Kalkan, Yıldıray; Erdivanlı, Özlem Çelebi; Dursun, Engin

    2015-08-01

    The results support that chronic electromagnetic field exposure may cause damage by leading to neuronal degeneration of the auditory system. Numerous researches have been done about the risks of exposure to the electromagnetic fields that occur during the use of these devices, especially the effects on hearing. The aim of this study is to evaluate the effects of the electromagnetic waves emitted by the mobile phones through the electrophysiological and histological methods. Twelve adult Wistar albino rats were included in the study. The rats were divided into two groups of six rats. The study group was exposed to the electromagnetic waves over a period of 30 days. The control group was not given any exposure to the electromagnetic fields. After the completion of the electromagnetic wave application, the auditory brainstem responses of both groups were recorded under anesthesia. The degeneration of cochlear nuclei was graded by two different histologists, both of whom were blinded to group information. The histopathologic and immunohistochemical analysis showed neuronal degeneration signs, such as increased vacuolization in the cochlear nucleus, pyknotic cell appearance, and edema in the group exposed to the electromagnetic fields compared to the control group. The average latency of wave in the ABR was similar in both groups (p > 0.05).

  8. The Effect of Chronic Methamphetamine Exposure on the Hippocampal and Olfactory Bulb Neuroproteomes of Rats.

    Directory of Open Access Journals (Sweden)

    Rui Zhu

    Full Text Available Nowadays, drug abuse and addiction are serious public health problems in the USA. Methamphetamine (METH is one of the most abused drugs and is known to cause brain damage after repeated exposure. In this paper, we conducted a neuroproteomic study to evaluate METH-induced brain protein dynamics, following a two-week chronic regimen of an escalating dose of METH exposure. Proteins were extracted from rat brain hippocampal and olfactory bulb tissues and subjected to liquid chromatography-mass spectrometry (LC-MS/MS analysis. Both shotgun and targeted proteomic analysis were performed. Protein quantification was initially based on comparing the spectral counts between METH exposed animals and their control counterparts. Quantitative differences were further confirmed through multiple reaction monitoring (MRM LC-MS/MS experiments. According to the quantitative results, the expression of 18 proteins (11 in the hippocampus and 7 in the olfactory bulb underwent a significant alteration as a result of exposing rats to METH. 13 of these proteins were up-regulated after METH exposure while 5 were down-regulated. The altered proteins belonging to different structural and functional families were involved in processes such as cell death, inflammation, oxidation, and apoptosis.

  9. The Association between Toxic Exposures and Chronic Multisymptom Illness in Veterans of the Wars of Iraq and Afghanistan

    Science.gov (United States)

    DeBeer, Bryann B.; Davidson, Dena; Meyer, Eric C.; Kimbrel, Nathan A.; Gulliver, Suzy B.; Morissette, Sandra B.

    2017-01-01

    Objective The purpose of this study was to determine if post-9/11 veterans deployed to the Iraq and Afghanistan conflicts experienced toxic exposures and whether they are related to symptoms of Chronic Multisymptom Illness (CMI). Methods Data from 224 post-9/11 veterans who self-reported exposure to hazards in theater were analyzed using hierarchical regression. Results Of the sample, 97.2% endorsed experiencing one or more potentially toxic exposure. In a regression model, toxic exposures and CMI symptoms were significantly associated above and beyond covariates. Follow-up analyses revealed that pesticide exposures, but not smoke inhalation was associated with CMI symptoms. Conclusions These findings suggest that toxic exposures were common among military personnel deployed to the most recent conflicts, and appear to be associated with CMI symptoms. Additional research on the impact of toxic exposures on returning Iraq and Afghanistan Veterans’ health is needed. PMID:28045798

  10. The basal kinetic parameters of glycogen synthase in human myotube cultures are not affected by chronic high insulin exposure

    DEFF Research Database (Denmark)

    Gaster, M; Schrøder, H D; Handberg, A

    2001-01-01

    results show that chronic exposure of human myotubes to high insulin with or without high glucose did not affect the basal kinetic parameters but abolished the reactivity of GS to acute insulin stimulation. We suggest that insulin induced insulin resistance of GS is caused by a failure of acute insulin......There is no consensus regarding the results from in vivo and in vitro studies on the impact of chronic high insulin and/or high glucose exposure on acute insulin stimulation of glycogen synthase (GS) kinetic parameters in human skeletal muscle. The aim of this study was to evaluate the kinetic...... parameters of glycogen synthase activity in human myotube cultures at conditions of chronic high insulin combined or not with high glucose exposure, before and after a subsequent acute insulin stimulation. Acute insulin stimulation significantly increased the fractional activity (FV(0.1)) of GS, increased...

  11. Kalrn promoter usage and isoform expression respond to chronic cocaine exposure

    Directory of Open Access Journals (Sweden)

    Ma Xin-Ming

    2011-02-01

    Full Text Available Abstract Background The long-term effects of cocaine on behavior are accompanied by structural changes in excitatory glutamatergic synapses onto the medium spiny neurons of the striatum. The Kalrn gene encodes several functionally distinct isoforms; these multidomain guanine nucleotide exchange factors (GEFs contain additional domains known to interact with phosphatidylinositides as well as with a number of different proteins. Through their activation of Rho proteins and their interactions with other proteins, the different Kalirin isoforms affect cytoskeletal organization. Chronic exposure of adult male rodents to cocaine increases levels of Kalirin 7 in the striatum. When exposed chronically to cocaine, mice lacking Kalirin 7, the major adult isoform, fail to show an increase in dendritic spine density in the nucleus accumbens, show diminished place preference for cocaine, and exhibit increased locomotor activity in response to cocaine. Results The use of alternate promoters and 3'-terminal exons of the mouse Kalrn gene were investigated using real-time quantitative polymerase chain reaction. While the two most distal full-length Kalrn promoters are used equally in the prefrontal cortex, the more proximal of these promoters accounts for most of the transcripts expressed in the nucleus accumbens. The 3'-terminal exon unique to the Kalirin 7 isoform accounts for a greater percentage of the Kalrn transcripts in prefrontal cortex than in nucleus accumbens. Western blot analyses confirmed these differences. Chronic cocaine treatment increases usage of the promoter encoding the Δ-Kalirin isoforms but does not alter full-length Kalirin promoter usage. Usage of the 3'-terminal exon unique to Kalirin 7 increases following chronic cocaine exposure. Conclusions Kalrn promoter and 3'-terminal exon utilization are region-specific. In the nucleus accumbens, cocaine-mediated alterations in promoter usage and 3'-terminal exon usage favor expression of

  12. Chronic Organic Solvent Exposure Changes Visual Tracking in Men and Women

    Directory of Open Access Journals (Sweden)

    Ana R. de Oliveira

    2017-11-01

    Full Text Available Organic solvents can change CNS sensory and motor function. Eye-movement analyses can be important tools when investigating the neurotoxic changes that result from chronic organic solvent exposure. The current research measured the eye-movement patterns of men and women with and without histories of chronic organic solvent exposure. A total of 44 volunteers between 18 and 41 years old participated in this study; 22 were men (11 exposed and 11 controls, and 22 were women (11 exposed and 11 controls. Eye movement was evaluated using a 250-Hz High-Speed Video Eye Tracker Toolbox (Cambridge Research Systems via an image of a maze. Specific body indices of exposed and non-exposed men and women were measured with an Inbody 720 to determine whether the differences in eye-movement patterns were associated with body composition. The data were analyzed using IBM SPSS Statistics version 20.0.0. The results indicated that exposed adults showed significantly more fixations (t = 3.82; p = 0.001; r = 0.51 and longer fixations (t = 4.27; p = 0.001, r = 0.54 than their non-exposed counterparts. Comparisons within men (e.g., exposed and non-exposed showed significant differences in the number of fixations (t = 2.21; p = 0.04; r = 0.20 and duration of fixations (t = 3.29; p = 0.001; r = 0.35. The same was true for exposed vs. non-exposed women, who showed significant differences in the number of fixations (t = 3.10; p = 0.001; r = 0.32 and fixation durations (t = 2.76; p = 0.01; r = 0.28. However, the results did not show significant differences between exposed women and men in the number and duration of fixations. No correlations were found between eye-movement pattern and body composition measures (p > 0.05. These results suggest that chronic organic solvent exposure affects eye movements, regardless of sex and body composition, and that eye tracking contributes to the investigation of the visual information processing disorders acquired by workers exposed to

  13. Chronic Organic Solvent Exposure Changes Visual Tracking in Men and Women.

    Science.gov (United States)

    de Oliveira, Ana R; Campos Neto, Armindo de Arruda; Bezerra de Medeiros, Paloma C; de Andrade, Michael J O; Dos Santos, Natanael A

    2017-01-01

    Organic solvents can change CNS sensory and motor function. Eye-movement analyses can be important tools when investigating the neurotoxic changes that result from chronic organic solvent exposure. The current research measured the eye-movement patterns of men and women with and without histories of chronic organic solvent exposure. A total of 44 volunteers between 18 and 41 years old participated in this study; 22 were men (11 exposed and 11 controls), and 22 were women (11 exposed and 11 controls). Eye movement was evaluated using a 250-Hz High-Speed Video Eye Tracker Toolbox (Cambridge Research Systems) via an image of a maze. Specific body indices of exposed and non-exposed men and women were measured with an Inbody 720 to determine whether the differences in eye-movement patterns were associated with body composition. The data were analyzed using IBM SPSS Statistics version 20.0.0. The results indicated that exposed adults showed significantly more fixations ( t = 3.82; p = 0.001; r = 0.51) and longer fixations ( t = 4.27; p = 0.001, r = 0.54) than their non-exposed counterparts. Comparisons within men (e.g., exposed and non-exposed) showed significant differences in the number of fixations ( t = 2.21; p = 0.04; r = 0.20) and duration of fixations ( t = 3.29; p = 0.001; r = 0.35). The same was true for exposed vs. non-exposed women, who showed significant differences in the number of fixations ( t = 3.10; p = 0.001; r = 0.32) and fixation durations ( t = 2.76; p = 0.01; r = 0.28). However, the results did not show significant differences between exposed women and men in the number and duration of fixations. No correlations were found between eye-movement pattern and body composition measures ( p > 0.05). These results suggest that chronic organic solvent exposure affects eye movements, regardless of sex and body composition, and that eye tracking contributes to the investigation of the visual information processing disorders acquired by workers exposed to

  14. Chronic exposure to microcystin-LR affected mitochondrial DNA maintenance and caused pathological changes of lung tissue in mice

    International Nuclear Information System (INIS)

    Li, Xinxiu; Xu, Lizhi; Zhou, Wei; Zhao, Qingya; Wang, Yaping

    2016-01-01

    Microcystin-LR (MC-LR), an important variant of cyanotoxin family, was frequently encountered in the contaminated aquatic environment and taken as a potent hepatotoxin. However, a little was known on the association between the long-term MC-LR exposure and lung damage. In this study, we investigated the changes of the pulmonary histopathology, mitochondrial DNA (mtDNA) integrity and the expression of mtDNA encoded genes in the mice with chronic exposed to MC-LR at different concentrations (1, 5, 10, 20 and 40 μg/L) for 12 months. Our results showed that the long-term and persistent exposure to MC-LR disturbed the balance of redox system, influenced mtDNA stability, changed the expression of mitochondrial genes in the lung cells. Notably, MC-LR exposure influenced the level of inflammatory cytokines and resulted in thickening of the alveolar septa. In conclusion, chronic exposure to MC-LR affected mtDNA maintenance, and caused lung impairment in mice. - Highlights: • A simulated natural exposure to MC-LR caused the lung pathological changes. • The chronic exposure disturbed the redox system balance of lung tissue cells. • The chronic exposure impaired the mtDNA stability and mitochondria function. • The lung was one of the vulnerable organs to MC-LR exposure in mice. - Long-term exposure to MC-LR in drinking water disturbed the balance of redox system, affected mitochondrial DNA maintenance and caused lung impairment in mice.

  15. The Longitudinal Effects of Chronic Mediated Exposure to Political Violence on Ideological Beliefs About Political Conflicts Among Youths.

    Science.gov (United States)

    Gvirsman, Shira Dvir; Huesmann, L Rowell; Dubow, Eric F; Landau, Simha F; Boxer, Paul; Shikaki, Khalil

    This study examines the effects of chronic (i.e., repeated and cumulative) mediated exposure to political violence on ideological beliefs regarding political conflict. It centers on these effects on young viewers, from preadolescents to adolescents. Ideological beliefs refers here to support of war, perception of threat to one's nation, and normative beliefs concerning aggression toward the out-group. A longitudinal study was conducted on a sample of Israeli and Palestinian youths who experience the Israeli-Palestinian conflict firsthand ( N = 1,207). Two alternative hypotheses were tested: that chronic exposure via the media increases support for war and aggression and elevates feeling of threat, or that chronic exposure via the media strengthens preexisting beliefs. Results demonstrated that higher levels of exposure were longitudinally related to stronger support for war. Regarding normative beliefs about aggression and threat to one's nation, mediated exposure reinforced initial beliefs, rendering the youths more extreme in their attitudes. These results mostly support the conceptualization of the relation between media violence and behaviors as "reciprocally determined" or "reinforcing spirals." The results are also discussed in light of the differences found between the effect of exposure to political violence firsthand and exposure via the media.

  16. Effects of duration of stay in temperate area on thermoregulatory responses to passive heat exposure in tropical south-east Asian males residing in Japan

    Directory of Open Access Journals (Sweden)

    Wijayanto Titis

    2012-09-01

    Full Text Available Abstract Background In this study, we investigated the effects of duration of stay in a temperate area on the thermoregulatory responses to passive heat exposure of residents from tropical areas, particularly to clarify whether they would lose their heat tolerance during passive heat exposure through residence in a temperate country, Japan. Methods We enrolled 12 males (mean ± SE age 25.7 ± 1.3 years from south-east Asian countries who had resided in Japan for a mean of 24.5 ± 5.04 months, and 12 Japanese males (age 24.1 ± 0.9 years. Passive heat exposure was induced through leg immersion in hot water (42°C for 60 minutes under conditions of 28°C air temperature and 50% relative humidity. Results Compared with the Japanese group, the tropical group displayed a higher pre-exposure rectal temperature (P P = 0.03. Additionally, the tropical group showed a tendency towards a lower total sweat rate (P = 0.06 and lower local sweat rate on the forehead (P = 0.07. The tropical group also had a significantly longer sweating onset time on the upper back (P = 0.04 compared with the Japanese groups. The tropical group who stayed in Japan for > 23 months sweated earlier on the forehead and upper back than those who stayed in Japan P P = 0.03 for the forehead and upper back, respectively. There was a positive correlation between duration of stay in Japan and total sweat rate (r = 0.58, P r = −0.73, P = 0.01 and on the upper back (r = −0.66, P = 0.02. Other physiological indices measured in this study did not show any difference between the subjects in the tropical group who had lived in Japan for a shorter time and those who had lived there for a longer time. Conclusions We conclude that the nature of heat acclimatization of the sweating responses to passive heat exposure that are acquired from long-term heat acclimatization is decayed by a stay in a temperate area, as shown

  17. Chronic bronchiolitis in non-human primates after prolonged ozone exposure

    International Nuclear Information System (INIS)

    Eustis, S.L.

    1979-01-01

    Bonnet monkeys (Macaca radiata) were exposed to 0.0, 0.5, and 0.8 ppM ozone for 7, 28, or 90 consecutive d, eight h per d. Changes in the lung evoked by prolonged oxidant exposure were evaluated by light microscopy, scanning electron microscopy, transmission electron microscopy, autoradiography, and morphometry. Morphological changes were principally characterized as a low-grade chronic respiratory bronchiolitis. Proximal generations of respiratory bronchioles were the most consistently affected region of the pulmonary acinus. Major features of the bronchiolitis were intraluminal accumulations of macrophages and hypertrophy and hyperplasia of cuboidal bronchiolar epithelial cells. The degree of inflammation was greatest at the 0.8 ppM ozone concentration at each exposure period. The number of inflammatory cells observed at 90 d, however, was about one-half that observed at 7 d. Tritiated thymidine labeling and differential cell counts of respiratory bronchiolar epithelium demonstrated a proliferative response and an increase in the proportion of cubiodal bronchiolar cells which presumably function as the progenitor cell during cell renewal and repair of the epithelium. The labeling index remained elevated above control values through 90 d of ozone exposure despite a reduction below 7 d values at both 28 and 90 d. The epithelial hyperplasia persisted through 90 d at a level similar to but slightly above that present at 7 d. Since cell differentials remained shifted at 28 and 90 d, it appears that persistent ozone exposure delayed maturation and transformation of cubiodal bronchiolar cells to their mature phenotype

  18. Impact of chronic neonicotinoid exposure on honeybee colony performance and queen supersedure.

    Directory of Open Access Journals (Sweden)

    Christoph Sandrock

    Full Text Available BACKGROUND: Honeybees provide economically and ecologically vital pollination services to crops and wild plants. During the last decade elevated colony losses have been documented in Europe and North America. Despite growing consensus on the involvement of multiple causal factors, the underlying interactions impacting on honeybee health and colony failure are not fully resolved. Parasites and pathogens are among the main candidates, but sublethal exposure to widespread agricultural pesticides may also affect bees. METHODOLOGY/PRINCIPAL FINDINGS: To investigate effects of sublethal dietary neonicotinoid exposure on honeybee colony performance, a fully crossed experimental design was implemented using 24 colonies, including sister-queens from two different strains, and experimental in-hive pollen feeding with or without environmentally relevant concentrations of thiamethoxam and clothianidin. Honeybee colonies chronically exposed to both neonicotinoids over two brood cycles exhibited decreased performance in the short-term resulting in declining numbers of adult bees (-28% and brood (-13%, as well as a reduction in honey production (-29% and pollen collections (-19%, but colonies recovered in the medium-term and overwintered successfully. However, significantly decelerated growth of neonicotinoid-exposed colonies during the following spring was associated with queen failure, revealing previously undocumented long-term impacts of neonicotinoids: queen supersedure was observed for 60% of the neonicotinoid-exposed colonies within a one year period, but not for control colonies. Linked to this, neonicotinoid exposure was significantly associated with a reduced propensity to swarm during the next spring. Both short-term and long-term effects of neonicotinoids on colony performance were significantly influenced by the honeybees' genetic background. CONCLUSIONS/SIGNIFICANCE: Sublethal neonicotinoid exposure did not provoke increased winter losses. Yet

  19. Long-term consequences of chronic fluoxetine exposure on the expression of myelination-related genes in the rat hippocampus

    Science.gov (United States)

    Kroeze, Y; Peeters, D; Boulle, F; van den Hove, D L A; van Bokhoven, H; Zhou, H; Homberg, J R

    2015-01-01

    The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we studied the long-term consequences (40 days after treatment) of chronic fluoxetine exposure on genome-wide gene expression. During the treatment period, we measured body weight; and 1 week after treatment, cessation behavior in an SSRI-sensitive anxiety test was assessed. Gene expression was assessed in hippocampal tissue of adult rats using transcriptome analysis and several differentially expressed genes were validated in independent samples. Gene ontology analysis showed that upregulated genes induced by chronic fluoxetine exposure were significantly enriched for genes involved in myelination. We also investigated the expression of myelination-related genes in adult rats exposed to fluoxetine at early life and found two myelination-related genes (Transferrin (Tf) and Ciliary neurotrophic factor (Cntf)) that were downregulated by chronic fluoxetine exposure. Cntf, a neurotrophic factor involved in myelination, showed regulation in opposite direction in the adult versus neonatally fluoxetine-exposed groups. Expression of myelination-related genes correlated negatively with anxiety-like behavior in both adult and neonatally fluoxetine-exposed rats. In conclusion, our data reveal that chronic fluoxetine exposure causes on the long-term changes in expression of genes involved in myelination, a process that shapes brain connectivity and contributes to symptoms of psychiatric disorders. PMID:26393488

  20. Comparison of air pollution exposures in active vs. passive travel modes in European cities: A quantitative review.

    Science.gov (United States)

    de Nazelle, Audrey; Bode, Olivier; Orjuela, Juan Pablo

    2017-02-01

    Transport microenvironments tend to have higher air pollutant concentrations than other settings most people encounter in their daily lives. The choice of travel modes may affect significantly individuals' exposures; however such considerations are typically not accounted for in exposure assessment used in environmental health studies. In particular, with increasing interest in the promotion of active travel, health impact studies that attempt to estimate potential adverse consequences of potential increased pollutant inhalation during walking or cycling have emerged. Such studies require a quantification of relative exposures in travel modes. The literature on air pollution exposures in travel microenvironments in Europe was reviewed. Studies which measured various travel modes including at least walking or cycling in a simultaneous or quasi-simultaneous design were selected. Data from these studies were harmonized to allow for a quantitative synthesis of the estimates. Ranges of ratios and 95% confidence interval (CI) of air pollution exposure between modes and between background and transportation modes were estimated. Ten studies measuring fine particulate matter (PM 2.5 ), black carbon (BC), ultrafine particles (UFP), and/or carbon monoxide (CO) in the walk, bicycle, car and/or bus modes were included in the analysis. Only three reported on CO and BC and results should be interpreted with caution. Pedestrians were shown to be the most consistently least exposed of all across studies, with the bus, bicycle and car modes on average 1.3 to 1.5 times higher for PM 2.5 ; 1.1 to 1.7 times higher for UFP; and 1.3 to 2.9 times higher for CO; however the 95% CI included 1 for the UFP walk to bus ratio. Only for BC were pedestrians more exposed than bus users on average (bus to walk ratio 0.8), but remained less exposed than those on bicycles or in cars. Car users tended to be the most exposed (from 2.9 times higher than pedestrians for BC down to similar exposures to

  1. Pathogenic mechanisms in chronic obstructive pulmonary disease due to biomass smoke exposure.

    Science.gov (United States)

    Silva, Rafael; Oyarzún, Manuel; Olloquequi, Jordi

    2015-06-01

    Chronic obstructive pulmonary disease (COPD) mortality and morbidity have increased significantly worldwide in recent decades. Although cigarette smoke is still considered the main risk factor for the development of the disease, estimates suggest that between 25% and 33% of COPD patients are non-smokers. Among the factors that may increase the risk of developing COPD, biomass smoke has been proposed as one of the most important, affecting especially women and children in developing countries. Despite the epidemiological evidence linking exposure to biomass smoke with adverse health effects, the specific cellular and molecular mechanisms by which this pollutant can be harmful for the respiratory and cardiovascular systems remain unclear. In this article we review the main pathogenic mechanisms proposed to date that make biomass smoke one of the major risk factors for COPD. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  2. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida.

    Science.gov (United States)

    Jager, Tjalling; Crommentuijn, Trudie; van Gestel, Cornelis A M; Kooijman, Sebastiaan A L M

    2007-01-01

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level.

  3. Impacts of species introductions on the health of fish communities receiving chronic radionuclide exposures

    International Nuclear Information System (INIS)

    Yankovich, T.L.; Casselman, J.M.; Cornett, R.J.J.

    2006-01-01

    A study was conducted to evaluate the potential impacts of a northern pike introduction on the health of a fish community receiving chronic radionuclide exposure, primarily from 90 Sr. Overall, although significant changes occurred in the community composition and the health of fish populations following the pike introduction, these were not linked to radionuclide dose to fishes. This finding was further supported by assessing the health of forage fishes, which did not significantly change in the pre-versus post-pike fish communities and were comparable in condition to forage fishes inhabiting lakes with background radionuclide levels. Application of such resilient species as 'baseline organisms' can provide a useful tool in the routine monitoring of ecosystems affected by multiple stressors. (author)

  4. Lead elimination by ICRF 158 in rats after chronic lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Witting, U; Hultsch, E

    1981-02-01

    Lead elimination by ICRF 158, a lipophilic derivative of ethylene-diaminetetra-acetate (EDTA), was investigated in rats after chronic lead exposure. The animals had received a lead concentration of 550 ppm in their drinking water for 140 days. Subsequent treatment with ICRF 158 for 30 days led to increased mobilization and elimination of incorporated lead, and the lead-induced inhibition of hemosynthesis was removed. ICR 158 produced no renal damage in excess to lead-induced tubular nephrosis. Separate toxicity tests in mice demonstrated that is less toxic than CaNa/sub 2/EDTA. ICRF 158 does not form stable complexes with lead ions in vitro. The mechanism of action of this lipophilic EDTA derivative is compared to that of its hydrophilic correspondent, the chelating agent CaNa/sub 2/EDTA.

  5. Immune homeostasis disturbances in different generations of rats at chronic exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Mel'nikov, O.F.; Sambur, M.B.; Timchenko, S.V.; Rozenfel'd, L.G.; Yindik, V.M.; Zayats, T.A.

    1994-01-01

    The aim of the work was to study immune homeostasis disturbance in six generations of rats which were kept under the conditions of chronic exposure to small doses of low-intensity radiation resembling those after the accident at Chernobyl Atomic Power Station. The controls included the animals from Kiev vivarium. Leukopenia and lymphopenia of different stage, decrease of the absolute number of immunocompetent cell having Fc receptor to lg G, inhibition of their functional activity, increase of mastocytelike lymphocytes in the peripheral blood, stable suppression of natural cytotoxic cells activity has been found out in the rats of the experimental groups examined at the age 3, 6, 9 and 12 months. The revealed disturbances of cell immunity indices and nonspecific resistance factors depended on the age of the animals and their generation to greater extend in the young rats of F 1 -F 2 generation

  6. Chronic zinc exposure decreases the surface expression of NR2A-containing NMDA receptors in cultured hippocampal neurons.

    Directory of Open Access Journals (Sweden)

    Jia Zhu

    Full Text Available Zinc distributes widely in the central nervous system, especially in the hippocampus, amygdala and cortex. The dynamic balance of zinc is critical for neuronal functions. Zinc modulates the activity of N-methyl-D-aspartate receptors (NMDARs through the direct inhibition and various intracellular signaling pathways. Abnormal NMDAR activities have been implicated in the aetiology of many brain diseases. Sustained zinc accumulation in the extracellular fluid is known to link to pathological conditions. However, the mechanism linking this chronic zinc exposure and NMDAR dysfunction is poorly understood.We reported that chronic zinc exposure reduced the numbers of NR1 and NR2A clusters in cultured hippocampal pyramidal neurons. Whole-cell and synaptic NR2A-mediated currents also decreased. By contrast, zinc did not affect NR2B, suggesting that chronic zinc exposure specifically influences NR2A-containg NMDARs. Surface biotinylation indicated that zinc exposure attenuated the membrane expression of NR1 and NR2A, which might arise from to the dissociation of the NR2A-PSD-95-Src complex.Chronic zinc exposure perturbs the interaction of NR2A to PSD-95 and causes the disorder of NMDARs in hippocampal neurons, suggesting a novel action of zinc distinct from its acute effects on NMDAR activity.

  7. Murine pulmonary responses after sub-chronic exposure to aluminum oxide-based nanowhiskers

    Directory of Open Access Journals (Sweden)

    Adamcakova-Dodd Andrea

    2012-06-01

    Full Text Available Abstract Background Aluminum oxide-based nanowhiskers (AO nanowhiskers have been used in manufacturing processes as catalyst supports, flame retardants, adsorbents, or in ceramic, metal and plastic composite materials. They are classified as high aspect ratio nanomaterials. Our aim was to assess in vivo toxicity of inhaled AO nanowhisker aerosols. Methods Primary dimensions of AO nanowhiskers specified by manufacturer were 2–4 nm x 2800 nm. The aluminum content found in this nanomaterial was 30% [mixed phase material containing Al(OH3 and AlOOH]. Male mice (C57Bl/6 J were exposed to AO nanowhiskers for 4 hrs/day, 5 days/wk for 2 or 4 wks in a dynamic whole body exposure chamber. The whiskers were aerosolized with an acoustical dry aerosol generator that included a grounded metal elutriator and a venturi aspirator to enhance deagglomeration. Average concentration of aerosol in the chamber was 3.3 ± 0.6 mg/m3 and the mobility diameter was 150 ± 1.6 nm. Both groups of mice (2 or 4 wks exposure were necropsied immediately after the last exposure. Aluminum content in the lung, heart, liver, and spleen was determined. Pulmonary toxicity assessment was performed by evaluation of bronchoalveolar lavage (BAL fluid (enumeration of total and differential cells, total protein, activity of lactate dehydrogenase [LDH] and cytokines, blood (total and differential cell counts, lung histopathology and pulmonary mechanics. Results Following exposure, mean Al content of lungs was 0.25, 8.10 and 15.37 μg/g lung (dry wt respectively for sham, 2 wk and 4 wk exposure groups. The number of total cells and macrophages in BAL fluid was 2-times higher in animals exposed for 2 wks and 6-times higher in mice exposed for 4 wks, compared to shams (p p  Conclusions Sub-chronic inhalation exposures to aluminum-oxide based nanowhiskers induced increased lung macrophages, but no inflammatory or toxic responses were observed.

  8. Chronic ultraviolet exposure-induced p53 gene alterations in sencar mouse skin carcinogenesis model

    International Nuclear Information System (INIS)

    Tong, Ying; Smith, M.A.; Tucker, S.B.

    1997-01-01

    Alterations of the tumor suppressor gene p53 have been found in ultraviolet radiation (UVR) related human skin cancers and in UVR-induced murine skin tumors. However, links between p53 gene alterations and the stages of carcinogenesis induced by UVR have not been clearly defined. We established a chronic UVR exposure-induced Sencar mouse skin carcinogenesis model to determine the frequency of p53 gene alterations in different stages of carcinogenesis, including UV-exposed skin, papillomas, squamous-cell carcinomas (SCCs), and malignant spindle-cell tumors (SCTs). A high incidence of SCCs and SCTs were found in this model. Positive p53 nuclear staining was found in 10137 (27%) of SCCs and 12124 (50%) of SCTs, but was not detected in normal skin or papillomas. DNA was isolated from 40 paraffin-embedded normal skin, UV-exposed skin, and tumor sections. The p53 gene (exons 5 and 6) was amplified from the sections by using nested polymerase chain reaction (PCR). Subsequent single-strand conformation polymorphism (SSCP) assay and sequencing analysis revealed one point mutation in exon 6 (coden 193, C → A transition) from a UV-exposed skin sample, and seven point mutations in exon 5 (codens 146, 158, 150, 165, and 161, three C → T, two C → A, one C → G, and one A → T transition, respectively) from four SCTs, two SCCs and one UV-exposed skin sample. These experimental results demonstrate that alterations in the p53 gene are frequent events in chronic UV exposure-induced SCCs and later stage SCTs in Sencar mouse skin. 40 refs., 5 figs., 1 tab

  9. Sub-chronic lead exposure produces β1-adrenoceptor downregulation decreasing arterial pressure reactivity in rats.

    Science.gov (United States)

    Toscano, Cindy Medici; Simões, Maylla Ronacher; Alonso, Maria Jesus; Salaices, Mercedes; Vassallo, Dalton Valentim; Fioresi, Mirian

    2017-07-01

    Lead is considered a causative factor for hypertension and other cardiovascular diseases. To investigate the effects of sub-chronic lead exposure on blood pressure reactivity and cardiac β 1 -adrenoceptor activity and to evaluate whether the effects found in vitro are similar to those found in vivo. Male Wistar rats were randomly distributed into two groups: control rats (Ct) and rats administered drinking water containing 100ppm lead (Pb) for 30days. Blood pressure in the Pb rats increased starting from the first week of treatment until the end of the study [systolic blood pressure, Ct: 122±4 vs. Pb: 143±3mmHg; diastolic blood pressure, Ct: 63±4 vs. Pb: 84±4mmHg]. The heart rate was also increased (Ct: 299±11 vs. Pb: 365±11bpm), but the pressure reactivity to phenylephrine was decreased. Losartan and hexamethonium exhibited a greater reduction in blood pressure of Pb rats than in the Ct rats. Isoproterenol increased the left ventricular systolic and end-diastolic pressure, and heart rate only in Ct rats, suggesting that lead induced β 1 -adrenoceptor downregulation. Indomethacin reduced the blood pressure and heart rate in the Pb rats, suggesting the involvement of cyclooxygenase-derived products (which are associated with reduced nitric oxide bioavailability) in this process. These findings offer further evidence that the effects of sub-chronic lead exposure in vitro can be reproduced in vivo-even at low concentrations-thus triggering mechanisms for the development of hypertension. Therefore, lead should be considered an environmental risk factor for cardiovascular disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Chronic exposure to dim artificial light at night decreases fecundity and adult survival in Drosophila melanogaster.

    Science.gov (United States)

    McLay, L K; Green, M P; Jones, T M

    2017-07-01

    The presence of artificial light at night is expanding in geographical range and increasing in intensity to such an extent that species living in urban environments may never experience natural darkness. The negative ecological consequences of artificial night lighting have been identified in several key life history traits across multiple taxa (albeit with a strong vertebrate focus); comparable data for invertebrates is lacking. In this study, we explored the effect of chronic exposure to different night-time lighting intensities on growth, reproduction and survival in Drosophila melanogaster. We reared three generations of flies under identical daytime light conditions (2600lx) and one of four ecologically relevant ALAN treatments (0, 1, 10 or 100lx), then explored variation in oviposition, number of eggs produced, juvenile growth and survival and adult survival. We found that, in the presence of light at night (1, 10 and 100lx treatments), the probability of a female commencing oviposition and the number of eggs laid was significantly reduced. This did not translate into differences at the juvenile phase: juvenile development times and the probability of eclosing as an adult were comparable across all treatments. However, we demonstrate for the first time a direct link between chronic exposure to light at night (greater than 1lx) and adult survival. Our data highlight that ALAN has the capacity to cause dramatic shifts in multiple life history traits at both the individual and population level. Such shifts are likely to be species-specific, however a more in depth understanding of the broad-scale impact of ALAN and the relevant mechanisms driving biological change is urgently required as we move into an increasing brightly lit future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Effect of head-only sub-chronic GSM exposure on spatial memory of rats

    International Nuclear Information System (INIS)

    Ammari, Mohamed; Brillaud, Elsa; Lecomte, Anthony; Sakly, Mohsen; Abdelmelek, Hafedh; Seze, Rene de; Faculte des Sciences de Bizerte, Jarzouna

    2008-01-01

    Full text: Introduction: Low power electromagnetic fields (EMF) are suspected to produce deficit memory in rats. The study of Dubreuil et al (2003) showed that a short-term (10-15 days) exposure 'head-only' to GSM 900 MHz radio frequencies does not produce a deficit memory in adult rats. The aim of our experiment was to determine if head-only sub-chronic exposure (2 months) of rats to GSM signal for 45 min at a SAR = 1.5 W/Kg and for 15 min at 6 W/Kg induce deficit in spatial memory of rats in radial maze test. Materials and methods: Exposure system: Animals were placed in Plexiglas rockets with an individual loop antenna placed above the rat's head. Four animals were exposed at the time. Loop antennas were connected to a generator and emitted a GSM signal (900 MHz, pulsed at 217 Hz, 1/8 duty factor) 5 days / week for 8 weeks. Experimental group: 30 Sprague-Dawley male rats were randomly assigned to 5 different groups: a) 6 rats exposed 15 min at SAR = 6 W/Kg; b) 6 rats exposed 45 min at SAR = 1.5 W/g; c) 6 rats sham controls (3 for 5 min and 3 for 45 min, SAR = 0 W/Kg); d) 6 rats without any treatment and manipulation (cage control); e) 6 rats were injected (i.p) S.B.H 0.1 mg/Kg (Sigma Aldrich) as positive control group. Behavioural procedure: The radial maze protocol consists of two consecutive phases: the training task (10 days) and the test task (8 days). In the first phase, rats were trained to visit the 8 arms of the maze without returning to an arm already visited. In the second phase (8 days), a 45-min intra-trial delay was introduced after four visited arms. After the intra-delay, the rat was placed in the maze to finish the test task, which is visiting four other arms he had not visited. During the training task, exposure took place before the behavioural task. During the test task, exposure or sham-exposure took place during the intra-delay. Results and discussion: In all experiments, performance of exposed rats (1.5 and 6 W/Kg) was compared with that of

  12. The promise and challenge of virtual gaming technologies for chronic pain: the case of graded exposure for low back pain.

    Science.gov (United States)

    Trost, Zina; Zielke, Marjorie; Guck, Adam; Nowlin, Liza; Zakhidov, Djanhangir; France, Christopher R; Keefe, Francis

    2015-01-01

    Virtual reality (VR) technologies have been successfully applied to acute pain interventions and recent reviews have suggested their potential utility in chronic pain. The current review highlights the specific relevance of VR interactive gaming technologies for pain-specific intervention, including their current use across a variety of physical conditions. Using the example of graded-exposure treatment for pain-related fear and disability in chronic low back pain, we discuss ways that VR gaming can be harnessed to optimize existing chronic pain therapies and examine the potential limitations of traditional VR interfaces in the context of chronic pain. We conclude by discussing directions for future research on VR-mediated applications in chronic pain.

  13. Chronic respiratory aeroallergen exposure in mice induces epithelial-mesenchymal transition in the large airways.

    Directory of Open Access Journals (Sweden)

    Jill R Johnson

    Full Text Available Chronic allergic asthma is characterized by Th2-polarized inflammation and leads to airway remodeling and fibrosis but the mechanisms involved are not clear. To determine whether epithelial-mesenchymal transition contributes to airway remodeling in asthma, we induced allergic airway inflammation in mice by intranasal administration of house dust mite (HDM extract for up to 15 consecutive weeks. We report that respiratory exposure to HDM led to significant airway inflammation and thickening of the smooth muscle layer in the wall of the large airways. Transforming growth factor beta-1 (TGF-β1 levels increased in mouse airways while epithelial cells lost expression of E-cadherin and occludin and gained expression of the mesenchymal proteins vimentin, alpha-smooth muscle actin (α-SMA and pro-collagen I. We also observed increased expression and nuclear translocation of Snail1, a transcriptional repressor of E-cadherin and a potent inducer of EMT, in the airway epithelial cells of HDM-exposed mice. Furthermore, fate-mapping studies revealed migration of airway epithelial cells into the sub-epithelial regions of the airway wall. These results show the contribution of EMT to airway remodeling in chronic asthma-like inflammation and suggest that Th2-polarized airway inflammation can trigger invasion of epithelial cells into the subepithelial regions of the airway wall where they contribute to fibrosis, demonstrating a previously unknown plasticity of the airway epithelium in allergic airway disease.

  14. Behavioral and Physiological Responses to Nicotine Patch Administration Among Nonsmokers Based on Acute and Chronic Secondhand Tobacco Smoke Exposure.

    Science.gov (United States)

    Okoli, Chizimuzo; Kodet, Jonathan; Robertson, Heather

    2016-01-01

    Despite the large amount that is known about the physical health effects of secondhand tobacco smoke (SHS) exposure, little is known about the behavioral health effects. Nicotine, the principle psychoactive substance in SHS, elicits subjective mood and physiological responses in nonsmokers. However, no studies have examined the subjective mood or physiological responses to nicotine in nonsmokers while accounting for prior chronic or acute SHS exposure. A 7-mg nicotine patch was administered to 17 adult nonsmokers for 2 hr. Main outcome measures obtained at ½ hr, 1 hr, and 2 hr were subjective behavioral drug effects (based on eleven 10-cm Visual Analog Scales [VASs]) and the physiological measures of heart rate, blood pressure, and serum nicotine levels. Analysis of outcome data was based on participants' chronic (using hair nicotine) or acute (using saliva cotinine) SHS exposure. Greater chronic SHS exposure was negatively associated with pleasurable responses to nicotine administration ("drug feels good" score at 2-hr time point, Spearman's ρ = -.65, p < .004), whereas greater acute SHS exposure was associated with positive responses ("like feeling of drug" score at 2-hr time point, Spearman's ρ = .63, p < .01). There were no associations between chronic or acute exposure and physiological changes in response to nicotine administration. The findings of this study may be useful in providing preliminary empirical data for future explorations of the mechanism whereby SHS exposure can influence behavioral outcomes in nonsmokers. Such studies can inform future interventions to reduce the physical and behavioral health risks associated with SHS exposure. © The Author(s) 2015.

  15. Effects of chronic aluminum exposure on learning and memory and brain-derived nerve growth factor in rats

    Institute of Scientific and Technical Information of China (English)

    潘宝龙

    2013-01-01

    Objective To investigate the effects of chronic aluminum exposure on the learning and memory abilities and brain-derived nerve growth factor (BDNF) in SpragueDawley (SD) rats.Methods Thirty-two male SD rats were randomly and equally divided into 4 groups:control group and high-,middle-,and low-dose exposure groups.The rats in high-,middle-,and low-dose expo-

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

    Science.gov (United States)

    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.

  17. Effects of depleted uranium chronic exposure on detoxification systems in vivo and in vitro

    International Nuclear Information System (INIS)

    Rouas, C.

    2010-01-01

    Uranium (U) is a heavy metal naturally presents in the environment. The aim of this work is to study effects of a U exposure on organs involved in the detoxification: the kidney and the liver (and notably the xenobiotics metabolizing enzymes (XME)). In order to mimic population chronic exposure, rats were contaminated during 9 months through the drinking water (40 mg/L). In vivo results show that U, in our experimental conditions, does not induce neither nephrotoxicity nor sensitivity to increase a renal toxicity induced by gentamicin. In the liver, U provokes impairments on the XME gene expression, particularly CYP3A. Nevertheless, paracetamole metabolism is modified only if it is administrated at a hepatotoxic dose. The in vitro results suggest an indirect effect of uranium on the XME, probably dependant of body adaptation mechanisms. Besides, in vitro studies were underline cytotoxic properties of U as well as the localisation of its soluble and/or participated forms in cytoplasmic and nuclear compartment. (author)

  18. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida

    Energy Technology Data Exchange (ETDEWEB)

    Jager, Tjalling [Department of Theoretical Biology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands)]. E-mail: tjalling@bio.vu.nl; Crommentuijn, Trudie [Ministry of Spatial Planning, Housing and the Environment (VROM), Rijnstraat 8, P.O. Box 30945, 2500 GX, The Hague (Netherlands); Gestel, Cornelis A.M. van [Department of Animal Ecology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands); Kooijman, Sebastiaan A.L.M. [Department of Theoretical Biology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands)

    2007-01-15

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level. - Exposure to chlorpyrifos in food affects reproduction in springtails according to two distinct toxic mechanisms.

  19. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida

    International Nuclear Information System (INIS)

    Jager, Tjalling; Crommentuijn, Trudie; Gestel, Cornelis A.M. van; Kooijman, Sebastiaan A.L.M.

    2007-01-01

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level. - Exposure to chlorpyrifos in food affects reproduction in springtails according to two distinct toxic mechanisms

  20. Nuclear toxicology file: ecological consequences of a chronic exposure to uranium

    International Nuclear Information System (INIS)

    Adam, Ch.; Alonzo, F.; Bonzom, J.M.; Gilbin, R.; Garnier-Laplace, J.; Simon, O.

    2008-01-01

    This article presents the thought process and the current developments, based on the experimental acquisition of the answers of the alive organisms to the chronic low dose exposures of natural uranium in fresh water, to identify the consequences of this exposure on the populations composing the ecosystems. The results acquired on the zebra fish (Danio rerio) show an impact on the first steps of development. We note a delay of hatching upon 40 % from 20 μg/l of uranium. This delay comes along with a decrease of the size and with a reduction of the growth of larvas as well as with an increase of their mortality for higher uranium concentration. For adults exposed to uranium a decrease of reproduction success is observed from a concentration of 20μg/l. The consequences in term of fertility (total number of laid roes) are drastic, with a reduction of a factor 2 and 60, for the organisms exposed respectively to 20 and 250 μg/l of uranium. A study was also made on several generations (populations of benthic invertebrates), it suggests an adaptation (genetic selection) but created a bigger fragility to a new environment even identical to their environment of origin with notably a decrease of the reproduction. (N.C.)

  1. Effects of long-term chronic exposure to radionuclides in plant populations

    International Nuclear Information System (INIS)

    Geras'kin, S.; Evseeva, T.; Oudalova, A.

    2013-01-01

    The results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hairgrass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate the effects of long-term chronic exposure to radionuclides are discussed. Plant populations growing in areas with relatively low levels of pollution are characterized by an increased level of both cytogenetic disturbances and genetic diversity. Although ionizing radiation causes primary damage at the molecular level, there are emergent effects at the level of populations, non-predictable from the knowledge of elementary mechanisms of cellular effects formation. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage could be accompanied by a decrease in reproductive capacity. However, in less contaminated sites, because of the scarcity of data available, a steady relationship between cytogenetic effects and reproductive capacity was not revealed. Under radioactive contamination of the plant's environment, a population's resistance to exposure may increase. However, there are radioecological situations where an enhanced radioresistance has not evolved or has not persisted

  2. Chronic obstructive pulmonary disease symptom effects of long-term cumulative exposure to ambient levels of total suspended particulates and sulfur dioxide in California Seventh-Day Adventist residents

    Energy Technology Data Exchange (ETDEWEB)

    Euler, G.L.; Abbey, D.E.; Magie, A.R.; Hodgkin, J.E.

    1987-07-01

    Risk of chronic obstructive pulmonary disease symptoms due to long-term exposure to ambient levels of total suspended particulates (TSP) and sulfur dioxide (SO/sub 2/) symptoms was ascertained using the National Heart, Lung, and Blood Institute (NHLBI) respiratory symptoms questionnaire on 7445 Seventh-Day Adventists. They were non-smokers, at least 25 yr of age, and had lived 11 yr or more in areas ranging from high to low photochemical air pollution in California. Participant cumulative exposures to each pollutant in excess of four thresholds were estimated using monthly residence zip code histories and interpolated dosages from state air monitoring stations. These pollutant thresholds were entered individually and in combination in multiple logistic regression analyses with eight covariables including passive smoking. Statistically significant associations with chronic symptoms were seen for: SO/sub 2/ exposure above 4 pphm (104 mcg/m3), (p = .03), relative risk 1.18 for 500 hr/yr of exposure; and for total suspended particulates (TSP) above 200 mcg/m3, (p less than .00001), relative risk of 1.22 for 750 hr/yr.

  3. Variable effects of chronic intermittent ethanol exposure on ethanol drinking in a genetically diverse mouse cohort.

    Science.gov (United States)

    Lopez, Marcelo F; Miles, Michael F; Williams, Robert W; Becker, Howard C

    2017-02-01

    The BXD family of mice were generated by crossing and inbreeding ethanol-preferring C57BL/6J and ethanol-avoiding DBA/2J strains that differ greatly in genome sequence and other behaviors. This study evaluated variations in the level of voluntary ethanol intake in a cohort of 42 BXD strains and both progenitor strains using a model of alcohol dependence and relapse drinking. A total of 119 BXDs (85 males, 34 females) (n ∼ 4 per genotype; 1/genotype/sex/group) were evaluated along with males from both progenitor strains (n = 14-15/genotype). Mice were evaluated for intake using limited access (2 h/day) 2-bottle (15% v/v ethanol vs. water) model for 6 weeks (baseline intake). Each animal received 4 weekly cycles of chronic intermittent ethanol (CIE) vapor exposure (CIE group) or air control exposure (CTL group) (16 h/day × 4 days) interleaved by 5-day drinking test cycles. Blood ethanol concentrations (BEC) ranged from 150 to 300 mg/dl across genotypes. Baseline intake varied greatly among cases-from ∼0.8 to ∼2.9 g/kg. As expected, CIE exposure induced a significant increase in ethanol drinking in C57BL/6J relative to baseline as well as air controls that remained relatively stable over the four test cycles. In contrast, DBA/2J cases did not show a significant increase in consumption. Heritability of variation in baseline consumption, calculated from C57BL/6J and DBA/2J strains is about 54% but this increases following treatment to 60-80%. As expected from the marked difference between progenitors, ethanol intake and level of escalation varied greatly among BXDs after exposure (∼-1.3 to 2.6 g/kg). Interestingly, the magnitude and direction of changes in ethanol intake did not relate to BEC values of the preceding CIE exposure cycle. Overall, these data indicate significant variation in consumption and even escalation, much of it under genetic control, following repeated CIE treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Deer carcass decomposition and potential scavenger exposure to chronic wasting disease

    Science.gov (United States)

    Jennelle, C.S.; Samuel, M.D.; Nolden, C.A.; Berkley, E.A.

    2009-01-01

    Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy afflicting the Cervidae family in North America, causing neurodegeneration and ultimately death. Although there are no reports of natural cross-species transmission of CWD to noncervids, infected deer carcasses pose a potential risk of CWD exposure for other animals. We placed 40 disease-free white-tailed deer (Odocoileus virginianus) carcasses and 10 gut piles in the CWD-affected area of Wisconsin (USA) from September to April in 2003 through 2005. We used photos from remotely operated cameras to characterize scavenger visitation and relative activity. To evaluate factors driving the rate of carcass removal (decomposition), we used KaplanMeier survival analysis and a generalized linear mixed model. We recorded 14 species of scavenging mammals (6 visiting species) and 14 species of scavenging birds (8 visiting species). Prominent scavengers included American crows (Corvus brachyrhynchos), raccoons (Procyon lotor), and Virginia opossums (Didelphis virginiana). We found no evidence that deer consumed conspecific remains, although they visited gut piles more often than carcasses relative to temporal availability in the environment. Domestic dogs, cats, and cows either scavenged or visited carcass sites, which could lead to human exposure to CWD. Deer carcasses persisted for 18 days to 101 days depending on the season and year, whereas gut piles lasted for 3 days. Habitat did not influence carcass decomposition, but mammalian and avian scavenger activity and higher temperatures were positively associated with faster removal. Infected deer carcasses or gut piles can serve as potential sources of CWD prions to a variety of scavengers. In areas where surveillance for CWD exposure is practical, management agencies should consider strategies for testing primary scavengers of deer carcass material.

  5. Chronic exposure to low-levels of lead in the rat: biochemical and behavioural changes

    International Nuclear Information System (INIS)

    Rossouw, J.

    1987-01-01

    The prevalence of lead in the environment is a cause of continuing toxicology concern and there have been numerous human and animal studies to examine more thoroughly the possible consequences of exposure to this ecotoxicant. Because lead is highly toxic to the developing central nervous system, increasing concern over the rise in the lead content in the environment has been expressed. These concerns seem appropriate since more recent clinical studies have shown that prolonged exposure of children to so called 'subclinical' concentrations of lead may be associated with behavioural disorders, learning disabilities and mental retardation. Moreover, animal studies have shown that chronic perinatal low-level lead exposure elicits alterations in both learned and spontaneous behavioural patterns in the absence of typical outward signs of lead-induced neurological toxicity. No study however could relate behavioural changes to specific alterations in neurochemisty. The aim of this study was therefore to expose rats, in different stages of their development, to low-levels of lead in order to induce behavioural disorders and correlate latter with possible neurochemical changes. In accordance with the general aims of the study, the structuring of the thesis is as follows: (a) a discussion of the neurotransmitters in the brain in order to describe the different systems which have been investigated; (b) a review of appropriate literature regarding the kinetics, toxodynamics and neurotoxicity of lead and (c) a summary of the methods employed in the study. The following results are presented: (d) the effects of lead treatment on physical development of the rats; (e) the induction of behavioural supersensitivity and (f) the effects lead has on central receptors

  6. Cell cycle pathway dysregulation in human keratinocytes during chronic exposure to low arsenite.

    Science.gov (United States)

    Al-Eryani, Laila; Waigel, Sabine; Jala, Venkatakrishna; Jenkins, Samantha F; States, J Christopher

    2017-09-15

    Arsenic is naturally prevalent in the earth's crust and widely distributed in air and water. Chronic low arsenic exposure is associated with several cancers in vivo, including skin cancer, and with transformation in vitro of cell lines including immortalized human keratinocytes (HaCaT). Arsenic also is associated with cell cycle dysregulation at different exposure levels in multiple cell lines. In this work, we analyzed gene expression in HaCaT cells to gain an understanding of gene expression changes contributing to transformation at an early time point. HaCaT cells were exposed to 0 or 100nM NaAsO 2 for 7weeks. Total RNA was purified and analyzed by microarray hybridization. Differential expression with fold change≥|1.5| and p-value≤0.05 was determined using Partek Genomic Suite™ and pathway and network analyses using MetaCore™ software (FDR≤0.05). Cell cycle analysis was performed using flow cytometry. 644 mRNAs were differentially expressed. Cell cycle/cell cycle regulation pathways predominated in the list of dysregulated pathways. Genes involved in replication origin licensing were enriched in the network. Cell cycle assay analysis showed an increase in G2/M compartment in arsenite-exposed cells. Arsenite exposure induced differential gene expression indicating dysregulation of cell cycle control, which was confirmed by cell cycle analysis. The results suggest that cell cycle dysregulation is an early event in transformation manifested in cells unable to transit G2/M efficiently. Further study at later time points will reveal additional changes in gene expression related to transformation processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Effects of chronic exposure to ionising radiation in the Pacific oyster Crassostrea gigas

    Energy Technology Data Exchange (ETDEWEB)

    Fievet, B.; Devos, A.; Voiseux, C.; Leconte-Pradines, C. [Institut de Radioprotection et de Surete' Nucleaire (France); Dallas, L.; Jha, A. [University of Plymouth (United Kingdom)

    2014-07-01

    The Cotentin peninsula (Normandy, France) hosts nuclear industry facilities which operate with controlled discharges of radionuclides in the marine environment. Compared to natural radioactivity, the increase by artificial radionuclides is small but constant. As a consequence, marine species are chronically exposed to low additional doses of ionizing radiation (IR). The effects of chronic exposure to radionuclides were investigated in early stages of development of the Japanese oyster Crassostrea gigas. On the basis of literature, mollusks are expected to be particularly resistant to acute IR (UNSCEAR, 1996. Sources and effects of ionizing radiation. Report to the General Assembly, with Scientific Annex. 86 p). Two different chronic exposure conditions consisted in external ({sup 137}Cs) and internal ({sup 241}Am) irradiation for two weeks. Biological endpoints were analyzed in parallel at both the integrated (growth) and molecular (target stress gene expression) levels. To identify potential biological targets of IR, oysters were first exposed to very high dose rates and radionuclide activities with the perspective to reduce the levels and to derive dose-response curves. Although the initial exposure levels ({sup 137}Cs 30 000 μGy.h{sup -1}; {sup 241}Am 57 000 Bq.L{sup -1}) were many orders of magnitude higher than those encountered in the natural environment, no significant change in the measured parameters was observed. This result was surprising because data from the literature showed that exposure of mussel Mytilus edulis to {sup 3}H at lower doses rates (10-100 μGy.h{sup -1}) induced DNA damage in hemocytes (Jha et al., 2005. Impact of low doses of tritium on the marine mussel, Mytilus edulis: Genotoxic effects and tissue-specific bioconcentration. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 586, 47-57). To understand this apparent discrepancy between those two filtering bivalves, a new experiment was performed to compare the response

  8. The Effect of Chronic Oral Administration of Withania Somnifera Root on Learning and Memory in Diabetic Rats Using Passive Avoidance Test

    Directory of Open Access Journals (Sweden)

    M. Roghani

    2006-07-01

    Full Text Available Introduction & Objective: Diabetes mellitus (especially type I is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the potential anti-diabetic effect of the medicinal plant Withania somnifera (ashwagandha and the augmenting effect of its consumption on the memory and mental health, this study was conducted to evaluate the effect of chronic oral administration of ashwagandha root on learning and memory in diabetic rats using passive avoidance test. Materials & Methods: For this purpose, male Wistar diabetic rats were randomly divided into control, ashwagandha-treated control, diabetic, and ashwagandha-treated diabetic groups. Ashwagandha treatment continued for 1 to 2 months. For induction of diabetes, streptozotocin was injected i.p. at a single dose of 60 mg/kg. Serum glucose level was determined before the study and at 4th and 8th weeks after the experiment. In addition, for evaluation of learning and memory, initial latency (IL and step-through latency (STL were determined after 1 and 2 months using passive avoidance test. Results: It was found that one- and two-month administration of ashwagandha root at a weight ratio of 1/15 has not any significant hypoglycemic effect in treated control and diabetic groups. Furthermore, there was a significant increase (p<0.05 in IL in diabetic and ashwagandha-treated diabetic groups after two months compared to control group. In this respect, there was no significant difference between diabetic and ashwagandha-treated diabetic groups. In addition, STL significantly increased in ashwagandha-treated control group after 1 (p<0.01 and 2 (p<0.05 month in comparison to control group. On the other hand, STL significantly decreased (p<0.05 in diabetic group and significantly increased (p<0.05 in ashwagandha-treated diabetic group as compared to control group after two months. Conclusion: In summary, chronic oral administration of

  9. The Effect of Chronic Hypercapnia on Oxygen Affinity and 2, 3 Diphosphoglycerate as Related to Submarine Exposure

    Science.gov (United States)

    The relationship between oxygen affinity and 2,3 diphosphoglycerate (2,3 DPG) in the red cell has been studied in chronic hypercapnia induced by...initial values after seven days of exposure. Both oxygen half-saturation pressure (P50) and the level of 2,3 DPG of the red cells followed the time

  10. Chronic exposure of the oligochaete Lumbriculus variegatus to Polycyclic Aromatic Compounds (PACs): Bioavailability and effects on reproduction

    NARCIS (Netherlands)

    León Paumen, M.; Stol, P.; ter Laak, T.L.; Kraak, M.H.S.; van Gestel, C.A.M.; Admiraal, W.

    2008-01-01

    This study aimed to monitor PAC availability to the oligochaete Lumbriculus variegatus during 28 days of exposure to spiked sediments, in order to obtain reliable chronic effect concentrations for reproduction. Sediment toxicity tests were performed using three pairs of PAC isomers: two homocyclic

  11. Chronic exposure of the oligochaete Lumbriculus variegatus to polycyclic aromatic compounds (PACs): bioavailability and effects on reproduction.

    NARCIS (Netherlands)

    Leon Paumen, M.; Stol, P.; ter Laak, T.L.; Kraak, M.H.S.; van Gestel, C.A.M.; Admiraal, W.

    2008-01-01

    This study aimed to monitor PAC availability to the oligochaete Lumbriculus variegatus during 28 days of exposure to spiked sediments, in order to obtain reliable chronic effect concentrations for reproduction. Sediment toxicity tests were performed using three pairs of PAC isomers: two homocyclic

  12. Concentrations of delta9-tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in blood and urine after passive exposure to Cannabis smoke in a coffee shop.

    Science.gov (United States)

    Röhrich, J; Schimmel, I; Zörntlein, S; Becker, J; Drobnik, S; Kaufmann, T; Kuntz, V; Urban, R

    2010-05-01

    Cannabinoid concentrations in blood and urine after passive exposure to cannabis smoke under real-life conditions were investigated in this study. Eight healthy volunteers were exposed to cannabis smoke for 3 h in a well-attended coffee shop in Maastricht, Netherlands. An initial blood and urine sample was taken from each volunteer before exposure. Blood samples were taken 1.5, 3.5, 6, and 14 h after start of initial exposure, and urine samples were taken after 3.5, 6, 14, 36, 60, and 84 h. The samples were subjected to immunoassay screening for cannabinoids and analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol (THC), 11-nor-hydroxy-Delta(9)-tetrahydrocannabinol (THC-OH), and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH). It could be demonstrated that all volunteers absorbed THC. However, the detected concentrations were rather small. None of the urine samples produced immunoassay results above the cutoff concentration of 25 ng/mL. THC-COOH concentrations up to 5.0 and 7.8 ng/mL before and after hydrolysis, respectively, were found in the quantitative GC-MS analysis of urine. THC could be detected in trace amounts close to the detection limit of the used method in the first two blood samples after initial exposure (1.5 and 3.5 h). In the 6 h blood samples, THC was not detectable anymore. THC-COOH could be detected after 1.5 h and was still found in 3 out of 8 blood samples after 14 h in concentrations between 0.5 and 1.0 ng/mL.

  13. Assessment of inhalation and ingestion doses from exposure to radon gas using passive and active detecting techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, A. H.; Jafaar, M. S. [Universiti Sains Malaysia, 11800 USM, Penang (Malaysia)

    2011-07-01

    The aim of this study was to assess an environmental hazard of radon exhalation rate from the samples of soil and drinking water in selected locations in Iraqi Kurdistan, passive (CR-39NTDs) and active (RAD7) detecting techniques has been employed. Long and short term measurements of emitted radon concentrations were estimated for 124 houses. High and lower radon concentration in soil samples was in the cities of Hajyawa and Er. Tyrawa, respectively. Moreover, for drinking water, high and low radon concentration was in the cities of Similan and Kelak, respectively. A comparison between our results with that mentioned in international reports had been done. Average annual dose equivalent to the bronchial epithelium, stomach and whole body in the cities of Kelak and Similan are estimated, and it was varied from 0.04{+-}0.01 mSv to 0.547{+-}0.018 mSv, (2.832{+-}0.22)x10{sup -5} to (11.972{+-}2.09)x10{sup -5} mSv, and (0.056 {+-}0.01) x10{sup -5} to (0.239{+-}0.01)x10{sup -5} mSv, respectively. This indicated that the effects of dissolved radon on the bronchial epithelium are much than on the stomach and whole body. (authors)

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

    Science.gov (United States)

    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.

  15. Chronic ethanol exposure downregulates hepatic expression of pregnane X receptor and P450 3A11 in female ICR mice

    International Nuclear Information System (INIS)

    Wang Jianping; Xu Dexiang; Sun Meifang; Chen Yuanhua; Wang Hua; Wei Wei

    2005-01-01

    Pregnane X receptor (PXR) is a nuclear receptor that regulates cytochrome P450 3A (CYP3A) gene transcription in a ligand-dependent manner. Ethanol has been reported to be either an inducer or an inhibitor of CYP3A expression. In this study, we investigated the effects of chronic ethanol exposure on PXR and P450 3A11 gene expression in mouse liver. Female ICR mice were administered by gavage with different doses (1000, 2000 and 4000 mg/kg) of ethanol for up to 5 weeks. Hepatic PXR and P450 3A11 mRNA levels were measured using RT-PCR. Erythromycin N-demethylase (ERND) activity was used as an indicator of CYP3A protein expression. Results showed that chronic ethanol exposure markedly decreased hepatic PXR and P450 3A11 mRNA levels. Consistent with downregulation of P450 3A11 mRNA, chronic ethanol exposure significantly decreased ERND activity in a dose-dependent manner. Additional experiment showed that chronic ethanol exposure significantly increased plasma endotoxin level and hepatic CD14 and TLR-4 mRNA expression, all of which were blocked by elimination of Gram-negative bacteria and endotoxin with antibiotics. Correspondingly, pretreatment with antibiotics reversed the downregulation of PXR and P450 3A11 mRNA expression and ERND activity in mouse liver. Furthermore, the downregulation of hepatic PXR and P450 3A11 mRNA expression was significantly attenuated in mice pretreated with GdCl 3 , a selective Kupffer cell toxicant. GdCl 3 pretreatment also significantly attenuated chronically ethanol-induced decrease in ERND activity. These results indicated that activation of Kupffer cells by gut-derived endotoxin contributes to downregulation of hepatic PXR and P450 3A11 expression during chronic alcohol intoxication

  16. Heavy Chronic Ethanol Exposure From Adolescence to Adulthood Induces Cerebellar Neuronal Loss and Motor Function Damage in Female Rats

    Directory of Open Access Journals (Sweden)

    Fernando B. R. da Silva

    2018-05-01

    Full Text Available Over the last years, heavy ethanol consumption by teenagers/younger adults has increased considerably among females. However, few studies have addressed the long-term impact on brain structures’ morphology and function of chronic exposure to high ethanol doses from adolescence to adulthood in females. In line with this idea, in the current study we investigated whether heavy chronic ethanol exposure during adolescence to adulthood may induce motor impairments and morphological and cellular alterations in the cerebellum of female rats. Adolescent female Wistar rats (35 days old were treated with distilled water or ethanol (6.5 g/kg/day, 22.5% w/v during 55 days by gavage. At 90 days of age, motor function of animals was assessed using open field (OF, pole, beam walking and rotarod tests. Following completion of behavioral tests, morphological and immunohistochemical analyses of the cerebellum were performed. Chronic ethanol exposure impaired significantly motor performance of female rats, inducing spontaneous locomotor activity deficits, bradykinesia, incoordination and motor learning disruption. Moreover, histological analysis revealed that ethanol exposure induced atrophy and neuronal loss in the cerebellum. These findings indicate that heavy ethanol exposure during adolescence is associated with long-lasting cerebellar degeneration and motor impairments in female rats.

  17. Chronic exposure to low concentrations of lead induces metabolic disorder and dysbiosis of the gut microbiota in mice.

    Science.gov (United States)

    Xia, Jizhou; Jin, Cuiyuan; Pan, Zihong; Sun, Liwei; Fu, Zhengwei; Jin, Yuanxiang

    2018-08-01

    Lead (Pb) is one of the most prevalent toxic, nonessential heavy metals that can contaminate food and water. In this study, effects of chronic exposure to low concentrations of Pb on metabolism and gut microbiota were evaluated in mice. It was observed that exposure of mice to 0.1mg/L Pb, supplied via drinking water, for 15weeks increased hepatic TG and TCH levels. The levels of some key genes related to lipid metabolism in the liver increased significantly in Pb-treated mice. For the gut microbiota, at the phylum level, the relative abundance of Firmicutes and Bacteroidetes changed obviously in the feces and the cecal contents of mice exposed to 0.1mg/L Pb for 15weeks. In addition, 16s rRNA gene sequencing further discovered that Pb exposure affected the structure and richness of the gut microbiota. Moreover, a 1 H NMR metabolic analysis unambiguously identified 31 metabolites, and 15 metabolites were noticeably altered in 0.1mg/L Pb-treated mice. Taken together, the data indicate that chronic Pb exposure induces dysbiosis of the gut microbiota and metabolic disorder in mice. Chronic Pb exposure induces metabolic disorder, dysbiosis of the gut microbiota and hepatic lipid metabolism disorder in mice. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Persistent effects of prior chronic exposure to corticosterone on reward-related learning and motivation in rodents.

    Science.gov (United States)

    Olausson, Peter; Kiraly, Drew D; Gourley, Shannon L; Taylor, Jane R

    2013-02-01

    Repeated or prolonged exposure to stress has profound effects on a wide spectrum of behavioral and neurobiological processes and has been associated with the pathophysiology of depression. The multifaceted nature of this disorder includes despair, anhedonia, diminished motivation, and disrupted cognition, and it has been proposed that depression is also associated with reduced reward-motivated learning. We have previously reported that prior chronic corticosterone exposure to mice produces a lasting depressive-like state that can be reversed by chronic antidepressant treatment. In the present study, we tested the effects of prior chronic exposure to corticosterone (50 μg/ml) administered to rats or to mice in drinking water for 14 days followed by dose-tapering over 9 days. The exposure to corticosterone produced lasting deficits in the acquisition of reward-related learning tested on a food-motivated instrumental task conducted 10-20 days after the last day of full dose corticosterone exposure. Rats exposed to corticosterone also displayed reduced responding on a progressive ratio schedule of reinforcement when tested on day 21 after exposure. Amitriptyline (200 mg/ml in drinking water) exposure for 14 days to mice produced the opposite effect, enhancing food-motivated instrumental acquisition and performance. Repeated treatment with amitriptyline (5 mg/kg, intraperitoneally; bid) subsequent to corticosterone exposure also prevented the corticosterone-induced deficits in rats. These results are consistent with aberrant reward-related learning and motivational processes in depressive states and provide new evidence that stress-induced neuroadaptive alterations in cortico-limbic-striatal brain circuits involved in learning and motivation may play a critical role in aspects of mood disorders.

  19. Dust exposure and chronic respiratory symptoms among coffee curing workers in Kilimanjaro: a cross sectional study.

    Science.gov (United States)

    Sakwari, Gloria; Bråtveit, Magne; Mamuya, Simon H D; Moen, Bente E

    2011-11-24

    Coffee processing causes organic dust exposure which may lead to development of respiratory symptoms. Previous studies have mainly focused on workers involved in roasting coffee in importing countries. This study was carried out to determine total dust exposure and respiratory health of workers in Tanzanian primary coffee-processing factories. A cross sectional study was conducted among 79 workers in two coffee factories, and among 73 control workers in a beverage factory. Personal samples of total dust (n = 45 from the coffee factories and n = 19 from the control factory) were collected throughout the working shift from the breathing zone of the workers. A questionnaire with modified questions from the American Thoracic Society questionnaire was used to assess chronic respiratory symptoms. Differences between groups were tested by using independent t-tests and Chi square tests. Poisson Regression Model was used to estimate prevalence ratio, adjusting for age, smoking, presence of previous lung diseases and years worked in dusty factories. All participants were male. The coffee workers had a mean age of 40 years and were older than the controls (31 years). Personal total dust exposure in the coffee factories were significantly higher than in the control factory (geometric mean (GM) 1.23 mg/m3, geometric standard deviation (GSD) (0.8) vs. 0.21(2.4) mg/m3). Coffee workers had significantly higher prevalence than controls for cough with sputum (23% vs. 10%; Prevalence ratio (PR); 2.5, 95% CI 1.0-5.9) and chest tightness (27% vs. 13%; PR; 2.4, 95% CI 1.1-5.2). The prevalence of morning cough, cough with and without sputum for 4 days or more in a week was also higher among coffee workers than among controls. However, these differences were not statistically significant. Workers exposed to coffee dust reported more respiratory symptoms than did the controls. This might relate to their exposure to coffee dust. Interventions for reduction of dust levels and provision of

  20. Tissue-specific Bio-accumulation of Metals in Fish during Chronic Waterborne and Dietary Exposures

    Directory of Open Access Journals (Sweden)

    M. Javed

    2012-10-01

    Full Text Available Juvenile (120-day three fish species viz. Catla catla, Labeo rohita and Cirrhina mrigala were exposed to chronic sub-lethal concentrations (1/3rd of LC50/LD50 of waterborne and dietary copper (Cu, cadmium (Cd, zinc (Zn, nickel (Ni and cobalt (Co, separately, in glass aquaria under constant water temperature (29oC, pH (7.5 and hardness (225 mgL-1 for 12 weeks. Waterborne and dietary exposures caused significantly variable accumulation of metals in three fish species that followed Zn>Ni>Cd>Co>Cu. Fish liver showed significantly higher tendency to accumulate Cu (69.64±25.35 µg g-1, Cd (68.93±21.65 µg g-1, Zn (91.46±29.53 µg g-1, Ni (74.64±18.61 µg g-1 and Co (22.65±20.56 µg g-1, followed by that of kidney and gills, with significant differences while muscle and bones exhibited significantly least tendency to accumulate all metals. Labeo rohita (31.63±2.43 µg g-1 and C. mrigala (31.43±13.70 µg g-1 exhibited significantly higher ability to amass metals than that of C. catla (27.96±10.28 µg g-1. Waterborne exposure caused significantly higher accumulation of metals in fish liver (72.69±27.91 µg g-1, followed by that in kidney, gills, skin, muscle, fins and bones with the average concentrations of 45.14±18.70, 39.47±21.13, 30.81±12.64, 22.65±17.34, 22.23±11.74 and 12.14±6.25 µg g-1, respectively. Dietary exposure resulted into significant escalation of metals in fish liver (58.23±32.44 µg g-1 while it was lowest in bones. Waterborne exposure caused significantly higher accumulation of all metals in fish body than that of dietary treatments.

  1. The effect of shorter exposure versus prolonged exposure on treatment outcome in Tourette syndrome and chronic tic disorders - an open trial.

    Science.gov (United States)

    van de Griendt, Jolande M T M; van Dijk, Maarten K; Verdellen, Cara W J; Verbraak, Marc J P M

    2018-01-11

    Exposure and response prevention has shown to be an effective strategy and is considered a first-line intervention in the behavioural treatment of tic disorders. Prior research demonstrated significant tic reduction after 12 two hour sessions. In this open trial, the question is addressed whether, relative to these prolonged sessions, exposure sessions of shorter duration yield differential outcome for patients with tic disorders. A total of 29 patients diagnosed with Tourette syndrome (TS) or chronic tic disorder were treated with shorter exposure sessions (1 h), and these data were compared to the data from a study about prolonged exposure (2 h, n = 21). Outcome was measured by the Yale Global Tic Severity Scale (YGTSS). Results suggest that after taking the difference in illness duration between the two groups into account, the effectiveness of shorter exposure sessions is not inferior to that of prolonged exposure. Results suggest that treatment with shorter exposure might be more efficient and more patients can be reached. Future research is needed to gain more insight into the mechanisms underlying the efficacy of behavioural treatments for tics.

  2. Review of the chronic exposure pathways models in MACCS [MELCOR Accident Consequence Code System] and several other well-known probabilistic risk assessment models

    International Nuclear Information System (INIS)

    Tveten, U.

    1990-06-01

    The purpose of this report is to document the results of the work performed by the author in connection with the following task, performed for US Nuclear Regulatory Commission, (USNRC) Office of Nuclear Regulatory Research, Division of Systems Research: MACCS Chronic Exposure Pathway Models: Review the chronic exposure pathway models implemented in the MELCOR Accident Consequence Code System (MACCS) and compare those models to the chronic exposure pathway models implemented in similar codes developed in countries that are members of the OECD. The chronic exposures concerned are via: the terrestrial food pathways, the water pathways, the long-term groundshine pathway, and the inhalation of resuspended radionuclides pathway. The USNRC has indicated during discussions of the task that the major effort should be spent on the terrestrial food pathways. There is one chapter for each of the categories of chronic exposure pathways listed above

  3. A motivational interviewing intervention to PREvent PAssive Smoke Exposure (PREPASE) in children with a high risk of asthma: design of a randomised controlled trial.

    Science.gov (United States)

    Hutchinson, Sasha G; Mesters, Ilse; van Breukelen, Gerard; Muris, Jean Wm; Feron, Frans Jm; Hammond, S Katharine; van Schayck, Constant P; Dompeling, Edward

    2013-02-27

    Especially children at risk for asthma are sensitive to the detrimental health effects of passive smoke (PS) exposure, like respiratory complaints and allergic sensitisation. Therefore, effective prevention of PS exposure in this group of vulnerable children is important. Based on previous studies, we hypothesized that an effective intervention program to prevent PS exposure in children is possible by means of a motivational interviewing tailored program with repeated contacts focussing on awareness, knowledge, beliefs (pros/cons), perceived barriers and needs of parents, in combination with feedback about urine cotinine levels of the children. The aim of the PREPASE study is to test the effectiveness of such an intervention program towards eliminating or reducing of PS exposure in children at risk for asthma. This article describes the protocol of the PREPASE study. The study is a one-year follow-up randomized controlled trial. Families with children (0-13 years of age) having an asthma predisposition who experience PS exposure at home are randomized into an intervention group receiving an intervention or a control group receiving care as usual. The intervention is given by trained research assistants. The intervention starts one month after a baseline measurement and takes place once per month for an hour during six home based counselling sessions. The primary outcome measure is the percentage of families curtailing PS exposure in children (parental report verified with the urine cotinine concentrations of the children) after 6 months. The secondary outcome measures include: household nicotine level, the child's lung function, airway inflammation and oxidative stress, presence of wheezing and questionnaires on respiratory symptoms, and quality of life. A process evaluation is included. Most of the measurements take place every 3 months (baseline and after 3, 6, 9 and 12 months of study). The PREPASE study incorporates successful elements of previous interventions

  4. A Chronic Longitudinal Characterization of Neurobehavioral and Neuropathological Cognitive Impairment in a Mouse Model of Gulf War Agent Exposure

    Science.gov (United States)

    Zakirova, Zuchra; Crynen, Gogce; Hassan, Samira; Abdullah, Laila; Horne, Lauren; Mathura, Venkatarajan; Crawford, Fiona; Ait-Ghezala, Ghania

    2016-01-01

    Gulf War Illness (GWI) is a chronic multisymptom illness with a central nervous system component that includes memory impairment as well as neurological and musculoskeletal deficits. Previous studies have shown that in the First Persian Gulf War conflict (1990–1991) exposure to Gulf War (GW) agents, such as pyridostigmine bromide (PB) and permethrin (PER), were key contributors to the etiology of GWI. For this study, we used our previously established mouse model of GW agent exposure (10 days PB+PER) and undertook an extensive lifelong neurobehavioral characterization of the mice from 11 days to 22.5 months post exposure in order to address the persistence and chronicity of effects suffered by the current GWI patient population, 24 years post-exposure. Mice were evaluated using a battery of neurobehavioral testing paradigms, including Open Field Test (OFT), Elevated Plus Maze (EPM), Three Chamber Testing, Radial Arm Water Maze (RAWM), and Barnes Maze (BM) Test. We also carried out neuropathological analyses at 22.5 months post exposure to GW agents after the final behavioral testing. Our results demonstrate that PB+PER exposed mice exhibit neurobehavioral deficits beginning at the 13 months post exposure time point and continuing trends through the 22.5 month post exposure time point. Furthermore, neuropathological changes, including an increase in GFAP staining in the cerebral cortices of exposed mice, were noted 22.5 months post exposure. Thus, the persistent neuroinflammation evident in our model presents a platform with which to identify novel biological pathways, correlating with emergent outcomes that may be amenable to therapeutic targeting. Furthermore, in this work we confirmed our previous findings that GW agent exposure causes neuropathological changes, and have presented novel data which demonstrate increased disinhibition, and lack of social preference in PB+PER exposed mice at 13 months after exposure. We also extended upon our previous work to

  5. Canines as sentinel species for assessing chronic exposures to air pollutants: part 1. Respiratory pathology.

    Science.gov (United States)

    Calderón-Garcidueñas, L; Mora-Tiscareño, A; Fordham, L A; Chung, C J; García, R; Osnaya, N; Hernández, J; Acuña, H; Gambling, T M; Villarreal-Calderón, A; Carson, J; Koren, H S; Devlin, R B

    2001-06-01

    A complex mixture of air pollutants is present in the ambient air in urban areas. People, animals, and vegetation are chronically and sequentially exposed to outdoor pollutants. The objective of this first of 2 studies is to evaluate by light and electron microscopy the lungs of Mexico City dogs and compare the results to those of 3 less polluted cities in MEXICO: One hundred fifty-two clinically healthy stray mongrel dogs (91 males/61 females), including 43 dogs from 3 less polluted cities, and 109 from southwest and northeast metropolitian Mexico City (SWMMC, NEMMC) were studied. Lungs of dogs living in Mexico City and Cuernavaca exhibited patchy chronic mononuclear cell infiltrates along with macrophages loaded with particulate matter (PM) surrounding the bronchiolar walls and extending into adjacent vascular structures; bronchiolar epithelial and smooth muscle hyperplasia, peribronchiolar fibrosis, microthrombi, and capillary and venule polymorphonuclear leukocytes (PMN) margination. Ultrafine PM was seen in alveolar type I and II cells, endothelial cells, interstitial macrophages (Mtheta), and intravascular Mtheta-like cells. Bronchoalveolar lavage showed significant numbers of alveolar macrophages undergoing proliferation. Exposure to complex mixtures of pollutants-predominantly particulate matter and ozone-is causing lung structural changes induced by the sustained inflammatory process and resulting in airway and vascular remodeling and altered repair. Cytokines released from both, circulating inflammatory and resident lung cells in response to endothelial and epithelial injury may be playing a role in the pathology described here. Deep concern exists for the potential of an increasing rise in lung diseases in child populations exposed to Mexico City's environment.

  6. Reproductive effects of the psychoactive beverage ayahuasca in male Wistar rats after chronic exposure

    Directory of Open Access Journals (Sweden)

    Alana de Fátima Andrade Santos

    Full Text Available Abstract Ayahuasca is a psychoactive beverage used ancestrally by indigenous Amazonian tribes and, more recently, by Christian religions in Brazil and other countries. This study aimed to investigate the reproductive effects of this beverage in male Wistar rats after chronic exposure. The rats were treated by gavage every other day for 70 days at 0 (control, 1×, 2×, 4× and 8× the dose used in a religious ritual (12 animals per group, and animals euthanized on the 71st day. Compared to controls, there was a significant decrease in food consumption and body weight gain in rats from the 4× and 8× groups, and a significant increase in the brain and stomach relative weight at the 8× group. There was a significant increase in total serum testosterone, and a decrease in spermatic transit time and spermatic reserves in the epididymis caudae in the 4× group, but not in the highest dose group. No significant changes were found in the other reproductive endpoints (spermatozoid motility and morphology, total spermatozoid count and daily sperm production, and histology of testis and epididymis. This study identified a no-observed-adverse-effect-level for chronic and reproductive effects of ayahuasca in male Wistar rats at 2× the ritualistic dose, which corresponds in this study to 0.62 mg/kg bw N, N-dimethyltryptamine, 6.6 mg/kg bw harmine and 0.52 mg/kg bw harmaline. A potential toxic effect of ayahuasca in male rats was observed at the 4× dose, with a non-monotonic dose–response. Studies investigating the role of ayahuasca components in regulating testosterone levels are needed to better understand this action.

  7. The effects of estrogens on learning in rats with chronic brain cholinergic deficiency in a Morris water test. Identification of the "passive swimming" component.

    Science.gov (United States)

    Mukhina, T V; Lermontova, N N; Van'kin, G I; Oettel, M; P'chev, V K; Bachurin, S O

    2004-03-01

    Chronic decreases in brain cholinergic functions due to intraventricular administration of the neurotoxin AF64A were accompanied by increases in the latent period of locating an invisible platform during training of rats in a Morris water test, as compared with control sham-operated animals. Recordings of the animals' movement trajectories using a video camera along with an original computer program (Behavioral Vision) showed that administration of 17beta-estradiol and its synthetic analog J-861 (0.2 mg/kg p.o. daily for seven days before and 10 days after single intraventricular injections of AF64A) improved learning. The directivity of platform search trajectories was assessed quantitatively using a new parameter--trajectory straightness. Introduction of the "passive swimming" parameter allowed periods of immobility in water to be identified within the total latent period in animals after administration of AF64A; 17beta-estradiol but not J-861 "eliminated" these periods. The new parameters (especially trajectory straightness) allowed the ability to learn to be discriminated from decreases in mobility, including mobility losses due to study agents, in the Morris water test.

  8. Chronic repeated exposure to weather-related stimuli elicits few symptoms of chronic stress in captive molting and non-molting European starlings (Sturnus vulgaris).

    Science.gov (United States)

    de Bruijn, Robert; Reed, J Michael; Romero, L Michael

    2017-10-01

    Repeated exposure to acute stressors causes dramatic changes in an animal's stress physiology and the cumulative effects are often called chronic stress. Recently we showed that short-term exposure to weather-related stimuli, such as temperature change, artificial precipitation, and food restriction, cause acute responses in captive European starlings (Sturnus vulgaris). Here, we examined the effect of repeated exposure to weather-related stressors on heart rate and corticosterone (CORT) of captive non-molting and molting European starlings. Four times every day for 3 weeks, birds were exposed to either 30 min of a subtle (3°C) decrease in temperature, a short bout of simulated rain, or 2 hr of food removal. The order and time of presentation were randomly assigned on each day. We found no differences in heart rate or heart rate variability. Furthermore, there were no changes in baseline CORT levels, CORT negative feedback efficacy, or maximal adrenal capacity. Mass increased across the experimental period only in molting birds. CORT responses to restraint were decreased in both groups following treatment, suggesting the birds had downregulated their responses to acute stress. Molting birds showed evidence of suppression of the HPA axis compared with non-molting birds, which is consistent with previous research. Overall, our data show that repeated exposure to weather-related stressors does not elicit most of the symptoms normally associated with chronic stress. © 2018 Wiley Periodicals, Inc.

  9. Gene expression in skin tumors induced in hairless mice by chronic exposure to ultraviolet B irradiation

    International Nuclear Information System (INIS)

    Sato, Hiromi; Tanaka, Misao; Kobayashi, Shizuko; Suzuki, Junko S.; Ogiso, Manabu; Tohyama, Chiharu

    1997-01-01

    We investigated the expressions of c-Ha-ras, c-jun, c-fos, c-myc genes and p53 protein in the development of skin tumours induced by chronic exposure to UVB without a photosensitizer using hairless mice. When mice were exposed to UVB at a dose of 2 kJ/m 2 three times a week, increased c-Ha-ras and c-myc transcripts were detected after only 5 weeks of exposure, while no tumour appeared on the exposed skin. The increase in gene expression continued until 25 weeks, when tumours, identified pathologically as mainly squamous cell carcinomas (SCC), developed in the dorsal skin. In these SCC, overexpression of c-fos mRNA was also observed along with the increases in c-Ha-ras and c-myc. A single dose of UVB (2 kJ/m 2 ) applied to the backs of hairless mice transiently induced overexpression of the early event genes c-fos, c-jun and c-myc, but not c-Ha-ras, in the exposed area of skin. Accumulation of p53 protein was determined by Western blotting analysis of immunohistochemistry using monoclonal antibodies PAb 240 or 246, which recognize mutant or wide type, respectively. In the SCC, a mutant p53 protein accumulated in the cytoplasm and nucleus. After single-dose irradiation, the increased wild-type p53 protein was observed in the nuclei of epidermal cells. The present results suggest that overexpression of the c-fos, c-myc and c-Ha-ras genes, and the mutational changes in p53 protein might be associated with skin photocarcinogenesis. Moreover, overexpression of the c-Ha-ras and c-myc genes might be an early event in the development of UVB-induced skin tumors in mice. (author)

  10. Damage to the testes of a marine fish, the plaice (Pleuronectes platessa), induced by chronic exposure to low dose rate radiation

    International Nuclear Information System (INIS)

    Knowles, J.F.

    1999-01-01

    Although most authorised disposals of liquid radioactive waste are to the sea, effects of chronic radiation exposure on reproductive endpoints in a marine fish have not so far been investigated. For this reason we have carried out a series of experiments into effects of chronic radiation exposure on plaice, a commercially important marine food species which spends much of its life in contact with sea bed sediments where exposure from radioactive contaminants have been shown to be highest

  11. HIGH-Resolution CT in Chronic Pulmonary Changes after Mustard Gas Exposure

    International Nuclear Information System (INIS)

    Bagheri, M.H.; Mostafavi, S.H.

    2003-01-01

    Purpose: To identify the findings of high-resolution CT (HRCT) of the lung in patients with previous sulfur mustard gas exposure, and to correlate these findings with clinical and chest X-ray (CXR) results. Material and Methods: 50 consecutive patients were studied prospectively. The clinical data were recorded. Standard p.a. CXR and HRCT of the lung and spirometry were performed. The findings of CXR, HRCT and clinical and spirometry results were scored between 0 and 3 according to the severity of the findings. Results: HRCT abnormality was detected in all 50 patients (100%), while CXR was abnormal in 40 patients (80%). The most common HRCT findings was airway abnormalities (bronchial wall thickening in 100% of cases). Other important findings were suggestive of interstitial lung disease (ILD) (80%), bronchiectasis (26%), and emphysema (24%). A statistically significant correlation was found between the severity of clinical presentation and that of the HCTR scores in patients with bronchiectasis, bronchitis and ILD (p< 0.05), but not with severity scores of HRCT in patients with emphysema. No significant correlation was found between severity scores of CXR findings. HRCT evidence of bronchial wall thickening and with a lower frequency ILD were present despite normal CXR in 20% of the patients. Conclusion: The results of this study suggest that bronchial wall thickening, ILD and emphysema are common chronic pulmonary sequelae of sulfur mustard injury. HRCT of the chest should be considered as the imaging modality of choice in chemical war injury

  12. HIGH-Resolution CT in Chronic Pulmonary Changes after Mustard Gas Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, M.H.; Mostafavi, S.H. [Shiraz Univ. of Medical Siences (Iran, Islamic Republic of). Dept. of Radiology; Hosseini, S.K. [Shiraz Univ. of Medical Siences (Iran, Islamic Republic of). Dept. of Internal Medicine; Alavi, S.A. [Medical Center for Chemical Warfare Victims Foundation, Shiraz (Iran, Islamic Republic of)

    2003-05-01

    Purpose: To identify the findings of high-resolution CT (HRCT) of the lung in patients with previous sulfur mustard gas exposure, and to correlate these findings with clinical and chest X-ray (CXR) results. Material and Methods: 50 consecutive patients were studied prospectively. The clinical data were recorded. Standard p.a. CXR and HRCT of the lung and spirometry were performed. The findings of CXR, HRCT and clinical and spirometry results were scored between 0 and 3 according to the severity of the findings. Results: HRCT abnormality was detected in all 50 patients (100%), while CXR was abnormal in 40 patients (80%). The most common HRCT findings was airway abnormalities (bronchial wall thickening in 100% of cases). Other important findings were suggestive of interstitial lung disease (ILD) (80%), bronchiectasis (26%), and emphysema (24%). A statistically significant correlation was found between the severity of clinical presentation and that of the HCTR scores in patients with bronchiectasis, bronchitis and ILD (p< 0.05), but not with severity scores of HRCT in patients with emphysema. No significant correlation was found between severity scores of CXR findings. HRCT evidence of bronchial wall thickening and with a lower frequency ILD were present despite normal CXR in 20% of the patients. Conclusion: The results of this study suggest that bronchial wall thickening, ILD and emphysema are common chronic pulmonary sequelae of sulfur mustard injury. HRCT of the chest should be considered as the imaging modality of choice in chemical war injury.

  13. Modelling the propagation of effects of chronic exposure to ionising radiation from individuals to populations

    Energy Technology Data Exchange (ETDEWEB)

    Alonzo, F. [Laboratory of Environmental Modelling, DEI/SECRE/LME, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache, Building 159, BP3, 13115 St-Paul-lez-Durance Cedex (France); Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)], E-mail: frederic.alonzo@irsn.fr; Hertel-Aas, T. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Gilek, M. [School of Life Sciences, Soedertoern University College, 14189 Huddinge (Sweden); Gilbin, R. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Oughton, D.H. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Garnier-Laplace, J. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)

    2008-09-15

    This study evaluated the potential effect of ionising radiation on population growth using simple population models and parameter values derived from chronic exposure experiments in two invertebrate species with contrasting life-history strategies. In the earthworm Eisenia fetida, models predicted increasing delay in population growth with increasing gamma dose rate (up to 0.6 generation times at 11 mGy h{sup -1}). Population extinction was predicted at 43 mGy h{sup -1}. In the microcrustacean Daphnia magna, models predicted increasing delay in population growth with increasing alpha dose rate (up to 0.8 generation times at 15.0 mGy h{sup -1}), only after two successive generations were exposed. The study examined population effects of changes in different individual endpoints (including survival, number of offspring produced and time to first reproduction). Models showed that the two species did not respond equally to equivalent levels of change, the fast growing daphnids being more susceptible to reduction in fecundity or delay in reproduction than the slow growing earthworms. This suggested that susceptibility of a population to ionising radiation cannot be considered independent of the species' life history.

  14. Chronic alcohol exposure disrupts top-down control over basal ganglia action selection to produce habits.

    Science.gov (United States)

    Renteria, Rafael; Baltz, Emily T; Gremel, Christina M

    2018-01-15

    Addiction involves a predominance of habitual control mediated through action selection processes in dorsal striatum. Research has largely focused on neural mechanisms mediating a proposed progression from ventral to dorsal lateral striatal control in addiction. However, over reliance on habit striatal processes may also arise from reduced cortical input to striatum, thereby disrupting executive control over action selection. Here, we identify novel mechanisms through which chronic intermittent ethanol exposure and withdrawal (CIE) disrupts top-down control over goal-directed action selection processes to produce habits. We find CIE results in decreased excitability of orbital frontal cortex (OFC) excitatory circuits supporting goal-directed control, and, strikingly, selectively reduces OFC output to the direct output pathway in dorsal medial striatum. Increasing the activity of OFC circuits restores goal-directed control in CIE-exposed mice. Our findings show habitual control in alcohol dependence can arise through disrupted communication between top-down, goal-directed processes onto basal ganglia pathways controlling action selection.

  15. Chronic scream sound exposure alters memory and monoamine levels in female rat brain.

    Science.gov (United States)

    Hu, Lili; Zhao, Xiaoge; Yang, Juan; Wang, Lumin; Yang, Yang; Song, Tusheng; Huang, Chen

    2014-10-01

    Chronic scream sound alters the cognitive performance of male rats and their brain monoamine levels, these stress-induced alterations are sexually dimorphic. To determine the effects of sound stress on female rats, we examined their serum corticosterone levels and their adrenal, splenic, and thymic weights, their cognitive performance and the levels of monoamine neurotransmitters and their metabolites in the brain. Adult female Sprague-Dawley rats, with and without exposure to scream sound (4h/day for 21 day) were tested for spatial learning and memory using a Morris water maze. Stress decreased serum corticosterone levels, as well as splenic and adrenal weight. It also impaired spatial memory but did not affect the learning ability. Monoamines and metabolites were measured in the prefrontal cortex (PFC), striatum, hypothalamus, and hippocampus. The dopamine (DA) levels in the PFC decreased but the homovanillic acid/DA ratio increased. The decreased DA and the increased 5-hydroxyindoleacetic acid (5-HIAA) levels were observed in the striatum. Only the 5-HIAA level increased in the hypothalamus. In the hippocampus, stress did not affect the levels of monoamines and metabolites. The results suggest that scream sound stress influences most physiologic parameters, memory, and the levels of monoamine neurotransmitter and their metabolites in female rats. Copyright © 2014. Published by Elsevier Inc.

  16. Chronic natural arsenic exposure affecting histoarchitecture of gonads in Black Bengal goats (Capra aegagrushircus

    Directory of Open Access Journals (Sweden)

    Md. Abdul Wares

    2015-06-01

    Full Text Available Arsenic is a major water pollutant that may cause serious health hazard (e.g., infertility in human and animal. We evaluated the changes in histoarchitecture of testes and ovaries of adult Black Bengal goats (n=10 reared in arsenic affected areas in Bangladesh. Grossly, we found insignificant variations among the testes and ovaries, but histological evaluation revealed an extensive alteration in morphology of both testes and ovaries in the arsenic affected goats. In testes, the thickening of tunica albugenia and trabeculae, widening of intertubular space between seminiferous tubules, and narrowing in diameter of seminiferous tubules were observed. In ovaries of arsenic affected goats, significant decrease in number of primary follicles and antral follicles were observed. The diameters of secondary and antral follicles were significantly reduced. The granulosa layer of antral follicles showed marked thickening. The findings indicate that chronic arsenic exposure alters the histoarchitecture of both male and female gonads in Black Bengal goat, and thereby may affect their reproductive performance.

  17. Drunk bugs: Chronic vapour alcohol exposure induces marked changes in the gut microbiome in mice.

    Science.gov (United States)

    Peterson, Veronica L; Jury, Nicholas J; Cabrera-Rubio, Raúl; Draper, Lorraine A; Crispie, Fiona; Cotter, Paul D; Dinan, Timothy G; Holmes, Andrew; Cryan, John F

    2017-04-14

    The gut microbiota includes a community of bacteria that play an integral part in host health and biological processes. Pronounced and repeated findings have linked gut microbiome to stress, anxiety, and depression. Currently, however, there remains only a limited set of studies focusing on microbiota change in substance abuse, including alcohol use disorder. To date, no studies have investigated the impact of vapour alcohol administration on the gut microbiome. For research on gut microbiota and addiction to proceed, an understanding of how route of drug administration affects gut microbiota must first be established. Animal models of alcohol abuse have proven valuable for elucidating the biological processes involved in addiction and alcohol-related diseases. This is the first study to investigate the effect of vapour route of ethanol administration on gut microbiota in mice. Adult male C57BL/6J mice were exposed to 4 weeks of chronic intermittent vapourized ethanol (CIE, N=10) or air (Control, N=9). Faecal samples were collected at the end of exposure followed by 16S sequencing and bioinformatic analysis. Robust separation between CIE and Control was seen in the microbiome, as assessed by alpha (pgut microbiota in mice. Significant increases in genus Alistipes (pgut-brain axis and align with previous research showing similar microbiota alterations in inflammatory states during alcoholic hepatitis and psychological stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Airway Epithelial Barrier Dysfunction in Chronic Obstructive Pulmonary Disease: Role of Cigarette Smoke Exposure.

    Science.gov (United States)

    Aghapour, Mahyar; Raee, Pourya; Moghaddam, Seyed Javad; Hiemstra, Pieter S; Heijink, Irene H

    2018-02-01

    The epithelial lining of the airway forms the first barrier against environmental insults, such as inhaled cigarette smoke, which is the primary risk factor for the development of chronic obstructive pulmonary disease (COPD). The barrier is formed by airway epithelial junctions, which are interconnected structures that restrict permeability to inhaled pathogens and environmental stressors. Destruction of the epithelial barrier not only exposes subepithelial layers to hazardous agents in the inspired air, but also alters the normal function of epithelial cells, which may eventually contribute to the development of COPD. Of note, disruption of epithelial junctions may lead to modulation of signaling pathways involved in differentiation, repair, and proinflammatory responses. Epithelial barrier dysfunction may be particularly relevant in COPD, where repeated injury by cigarette smoke exposure, pathogens, inflammatory mediators, and impaired epithelial regeneration may compromise the barrier function. In the current review, we discuss recent advances in understanding the mechanisms of barrier dysfunction in COPD, as well as the molecular mechanisms that underlie the impaired repair response of the injured epithelium in COPD and its inability to redifferentiate into a functionally intact epithelium.

  19. Chronic prenatal ethanol exposure increases adiposity and disrupts pancreatic morphology in adult guinea pig offspring.

    Science.gov (United States)

    Dobson, C C; Mongillo, D L; Brien, D C; Stepita, R; Poklewska-Koziell, M; Winterborn, A; Holloway, A C; Brien, J F; Reynolds, J N

    2012-12-17

    Ethanol consumption during pregnancy can lead to a range of adverse developmental outcomes in children, termed fetal alcohol spectrum disorder (FASD). Central nervous system injury is a debilitating and widely studied manifestation of chronic prenatal ethanol exposure (CPEE). However, CPEE can also cause structural and functional deficits in metabolic pathways in offspring. This study tested the hypothesis that CPEE increases whole-body adiposity and disrupts pancreatic structure in guinea pig offspring. Pregnant guinea pigs received ethanol (4 g kg(-1) maternal body weight per day) or isocaloric-sucrose/pair-feeding (control) for 5 days per week throughout gestation. Male and female CPEE offspring demonstrated growth restriction at birth, followed by a rapid period of catch-up growth before weaning (postnatal day (PD) 1-7). Whole-body magnetic resonance imaging (MRI) in young adult offspring (PD100-140) revealed increased visceral and subcutaneous adiposity produced by CPEE. At the time of killing (PD150-200), CPEE offspring also had increased pancreatic adipocyte area and decreased β-cell insulin-like immunopositive area, suggesting reduced insulin production and/or secretion from pancreatic islets. CPEE causes increased adiposity and pancreatic dysmorphology in offspring, which may signify increased risk for the development of metabolic syndrome and type 2 diabetes mellitus.

  20. Changes of medullary hemopoiesis produced by chronic exposure to tritium oxide and external γ-radiation

    International Nuclear Information System (INIS)

    Murzina, L.D.; Muksinova, K.N.

    1982-01-01

    A comparative study of a chronic effect of tritium oxide ( 3 HOH) and external γ-radiation by 137 Cs on medullary hemopoiesis was conducted in experiments on Wistar rats. 3 HOH was administered for 3mos., 37x10 4 Bk per lg per of body mass daily (the absorbed dose 10.8 Gy), external irradiation was given in correlated values of dose rates and integral doses. Bone marrow depopulation was 1.9 times as deeper in rats exposed to 3 HOH as compared to that in irradiated rats. This difference is caused by early and stable inhibition of erythropoiesis with the administration of the radionuclide. The integral index showing the injuring effect of tritium on erythropoiesis was 4 times as high as compared to that of external γ-irradiation by 137 Cs. The time course of value of the proliferative pool of bone marrow granulocytes with the exposure to 2 types of radiation was monotypic. Differences in maturing and functioning granulocytic pools were marked in early time of the experiment

  1. Subclinical decelerations during developing hypotension in preterm fetal sheep after acute on chronic lipopolysaccharide exposure

    Science.gov (United States)

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

    2015-01-01

    Subclinical (shallow) heart rate decelerations occur during neonatal sepsis, but there is limited information on their relationship with hypotension or whether they occur before birth. We examined whether subclinical decelerations, a fall in fetal heart rate (FHR) that remained above 100 bpm, were associated with hypotension in preterm fetal sheep exposed to lipopolysaccharide (LPS). Chronically-instrumented fetal sheep at 0.7 gestation received continuous low-dose LPS infusions (n = 15, 100 ng/kg over 24 h, followed by 250 ng/kg/24 h for 96 h) or saline (n = 8). Boluses of 1 μg LPS or saline were given at 48 and 72 h. FHR variability (FHRV) was calculated, and sample asymmetry was used to assess the severity and frequency of decelerations. Low-dose LPS infusion did not affect FHR. After the first LPS bolus, 7 fetuses remained normotensive, while 8 developed hypotension (a fall in mean arterial blood pressure of ≥5 mmHg). Developing hypotension was associated with subclinical decelerations, with a corresponding increase in sample asymmetry and FHRV (p < 0.05). The second LPS bolus was associated with similar but attenuated changes in FHR and blood pressure (p < 0.05). In conclusion, subclinical decelerations are not consistently seen during prenatal exposure to LPS, but may be a useful marker of developing inflammation-related hypotension before birth. PMID:26537688

  2. Metamorphosis of two amphibian species after chronic cadmium exposure in outdoor aquatic mesocosms

    Science.gov (United States)

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2005-01-01

    Amphibian larvae at contaminated sites may experience an alteration of metamorphic traits and survival compared to amphibians in uncontaminated conditions. Effects of chronic cadmium (Cd) exposure on the metamorphosis of American toads (Bufo americanus) and southern leopard frogs (Rana sphenocephala) were determined. The two species were reared separately from shortly after hatching through metamorphosis in outdoor mesocosms (1,325-L polyethylene cattle tanks) that simulated natural ponds and enhanced environmental realism relative to the laboratory. Both species exhibited a decrease in survival with increasing initial nominal aqueous Cd concentration. Cadmium treatment did not influence mass at metamorphosis for either species when survival was included as a covariate, but increased the age at metamorphosis for the American toads. The whole body Cd content of metamorphs increased with aqueous Cd treatment level for both species, and the American toads tended to possess more elevated residues. Cadmium quickly partitioned out of the water column and accumulated in and altered the abundance of the tadpoles' diet. Cadmium-contaminated sites may produce fewer metamorphs, and those that survive will metamorphose later and contain Cd. Interspecific differences in the response variables illustrate the importance of testing multiple species when assessing risk.

  3. Ways of pharmacological prophylaxis of stochastic and deterministic effects of chronical radiation exposure

    International Nuclear Information System (INIS)

    Kirillova, E.N.; Muksinova, K.N.; Revina, V.; Smirnov, D.; Sokolnikov, M.; Lukyanova, T.

    1996-01-01

    The prophylactics of late effects of exposure is the actual medico-social problem, because now there are large groups of persons who were exposed during occupational contact and living on territories contaminated by radionuclides. Most probable consequences of external and internal chronic influence of radiation may be the increase of malignant tumour frequency, the development of secondary myelo- and immuno-depressions, the earlier forming of sclerous and destructive processes, and the acceleration of senescence. The role of damages in immune system was not yet understood in pathogenesis of the late effects of radiation, but there are evidences that the decreasing of the immunologic supervision in period of forming the consequences of radiation influence enables to realize the cancerogenic effect of radiation. The purposes of this investigation are to decrease the frequency or to prevent the development of radiation consequences dangerous for health and life by using the method of modification of radiogenic damages in hemopoietic and immune systems by applying the pharmacological preparations with immunomodulating effects. The investigation tasks include: the study of modifying influence of pharmacological substances with different mechanisms of effect: myelopid (immunomodulating, and regulatory), β-carotin, Calendula officinalis (immunomodulating, and antioxidant), lipamid (detoxicating); the separate or complex applications of these substances; and the development of the optimum medico-prophylactic schemes. The advantages of these indicated preparations in comparison with the known (T-activin, thymogen, cytokines, etc.) are the absence of contraindications and the possibility to use per os. (author)

  4. Effects of acute or chronic ethanol exposure during adolescence on behavioral inhibition and efficiency in a modified water maze task.

    Directory of Open Access Journals (Sweden)

    Shawn K Acheson

    Full Text Available Ethanol is well known to adversely affect frontal executive functioning, which continues to develop throughout adolescence and into young adulthood. This is also a developmental window in which ethanol is misused by a significant number of adolescents. We examined the effects of acute and chronic ethanol exposure during adolescence on behavioral inhibition and efficiency using a modified water maze task. During acquisition, rats were trained to find a stable visible platform onto which they could escape. During the test phase, the stable platform was converted to a visible floating platform (providing no escape and a new hidden platform was added in the opposite quadrant. The hidden platform was the only means of escape during the test phase. In experiment 1, adolescent animals received ethanol (1.0 g/kg 30 min before each session during the test phase. In experiment 2, adolescent animals received chronic intermittent ethanol (5.0 g/kg for 16 days (PND30 To PND46 prior to any training in the maze. At PND72, training was initiated in the same modified water maze task. Results from experiment 1 indicated that acute ethanol promoted behavioral disinhibition and inefficiency. Experiment 2 showed that chronic intermittent ethanol during adolescence appeared to have no lasting effect on behavioral disinhibition or new spatial learning during adulthood. However, chronic ethanol did promote behavioral inefficiency. In summary, results indicate that ethanol-induced promotion of perseverative behavior may contribute to the many adverse behavioral sequelae of alcohol intoxication in adolescents and young adults. Moreover, the long-term effect of adolescent chronic ethanol exposure on behavioral efficiency is similar to that observed after chronic exposure in humans.

  5. Chronic Δ⁸-THC Exposure Differently Affects Histone Modifications in the Adolescent and Adult Rat Brain.

    Science.gov (United States)

    Prini, Pamela; Penna, Federica; Sciuccati, Emanuele; Alberio, Tiziana; Rubino, Tiziana

    2017-10-04

    Adolescence represents a vulnerable period for the psychiatric consequences of delta9-tetrahydrocannabinol (Δ⁸-THC) exposure, however, the molecular underpinnings of this vulnerability remain to be established. Histone modifications are emerging as important epigenetic mechanisms involved in the etiopathogenesis of psychiatric diseases, thus, we investigated the impact of chronic Δ⁸-THC exposure on histone modifications in different brain areas of female rats. We checked histone modifications associated to both transcriptional repression (H3K9 di- and tri-methylation, H3K27 tri-methylation) and activation (H3K9 and H3K14 acetylation) after adolescent and adult chronic Δ⁸-THC exposure in the hippocampus, nucleus accumbens, and amygdala. Chronic exposure to increasing doses of Δ⁸-THC for 11 days affected histone modifications in a region- and age-specific manner. The primary effect in the adolescent brain was represented by changes leading to transcriptional repression, whereas the one observed after adult treatment led to transcriptional activation. Moreover, only in the adolescent brain, the primary effect was followed by a homeostatic response to counterbalance the Δ⁸-THC-induced repressive effect, except in the amygdala. The presence of a more complex response in the adolescent brain may be part of the mechanisms that make the adolescent brain vulnerable to Δ⁸-THC adverse effects.

  6. Chronic exposure to chlorophenol related compounds in the pesticide production workplace and lung cancer: a meta-analysis.

    Science.gov (United States)

    Zendehdel, Rezvan; Tayefeh-Rahimian, Raana; Kabir, Ali

    2014-01-01

    Chlorophenols (CPs) and related phenoxyacetic acids (PAs) are pesticide groups contaminated with highly toxic 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) during production. PAs and CPs exposure is associated with risk of cancer, but the situation regarding lung cancer has not been clearly defined. We proposed a meta-analysis of published researches to evaluate relationship between chronic exposure to PAs and CPs in pesticide production workplaces and the risk of lung cancer. After searching PubMed, Scopus, Scholar Google, Web of Sciences until August 2013, the association between chronic PAs and CPs exposure in production workplace and lung cancer was studied in 15 cohort studies. The standardized mortality rate (SMR) and 95% confidence intervals (CI) were collected from the papers. We used random or fixed-effects models, Egger test, funnel plot and meta regression in our analysis. Five papers with six reports were included in the final analysis. The standardized mortality rate for lung cancer from the random model was 1.18 (95% CI: 1.03-1.35, p=0.014) with moderate heterogeneity. Publication bias was not found for included studies in meta-analysis (p=0.9). Our findings has strengthen the evidence of lung cancer from chronic exposure to chlorophenol related compounds (PAs, CPs).

  7. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn Exposure on Sea Cucumbers (Apostichopus japonicus

    Directory of Open Access Journals (Sweden)

    Li Li

    2016-01-01

    Full Text Available Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus exposed to heavy metals. Acute toxicity values (96 h LC50 were 2.697, 0.133, and 1.574 mg L−1 for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR decreased. The OCRs in all groups were significantly different than control (P muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained.

  8. Chronic arsenic exposure and its adverse health effects in Taiwan: A paradigm for management of a global environmental problem

    Directory of Open Access Journals (Sweden)

    Cheng-Che Lan

    2011-09-01

    Full Text Available It was estimated that, nearly 100 million people are at risk for drinking arsenic (As-contaminated drinking water. Although the WHO guideline recommends that levels of As in drinking water should not exceed 10 μm/L, it was estimated that more than 30 million people drink As-containing water at levels more than 50 μm/L in Bangladesh and India alone. Therefore, the adverse health effects resulting from chronic As exposure pose a global threat. In Taiwan, studies focusing on the health effects resulting from chronic As exposure through contaminated drinking water have been ongoing for more than 50 years. During the past half century, it was recognized that the impact of high As exposure on human health is much more complicated than originally anticipated. Chronic As exposure resulted in infamous blackfoot disease, which is unique to As endemic areas in Taiwan, and various diseases including cancers and non-cancers. Although the potential-biological outcomes have been well-documented, the pathomechanisms leading from As exposure to occurrence and development of the diseases remain largely unclear. One of the major obstacles that hindered further understanding regarding the adverse health effect resulting from chronic As exposure is documentation of cumulative As exposure from the distant past, which remains difficult as the present technologies mostly document relatively recent As exposure. Furthermore, the susceptibility to As exposure appears to differ between different ethnic groups and individuals and is modified by lifestyle factors including smoking habits and nutrition status. No consensus data has yet been reached even after comparing the study results obtained from different parts of the world focusing on associations between human As toxicity and genetic polymorphisms in terms of cellular detoxification enzymes, tumor suppressor proteins, and DNA repair pathway. With the availability of the new powerful “OMIC” technologies, it may

  9. Cadmium accumulation and elimination in tissues of juvenile olive flounder, Paralichthys olivaceus after sub-chronic cadmium exposure

    International Nuclear Information System (INIS)

    Kim, Seong-Gil; Jee, Jung-Hoon; Kang, Ju-Chan

    2004-01-01

    Cd accumulation and elimination in tissue of olive flounder. - Experiments were carried out to investigate the accumulation and elimination of cadmium (Cd) in tissues (gill, intestine, kidney, liver and muscle) of juvenile olive flounder, Paralichthys olivaceus, exposed to sub-chronic concentrations (0, 10, 50, 100 μg l -1 ) of Cd. Cd exposure resulted in an increased Cd accumulation in tissues of flounder with exposure periods and concentration, and Cd accumulation in gill and liver increased linearly with the exposure time. At 20 days of Cd exposure, the order of Cd accumulation in organs was gill > intestine > liver > kidney > muscle and after 30 days of exposure, those were intestine > gill > liver > kidney > muscle. An inverse relationship was observed between the accumulation factor (AF) and the exposure level, but AF showed an increase with exposure time. During the depuration periods, Cd concentration in the gill, intestine and liver decreased immediately following the end of the exposure periods. No significant difference was found Cd in concentration in the kidney and muscle during depuration periods. The order of Cd elimination rate in organs were decreased intestine > liver > gill during depuration periods

  10. The broad scope of health effects from chronic arsenic exposure: update on a worldwide public health problem.

    Science.gov (United States)

    Naujokas, Marisa F; Anderson, Beth; Ahsan, Habibul; Aposhian, H Vasken; Graziano, Joseph H; Thompson, Claudia; Suk, William A

    2013-03-01

    Concerns for arsenic exposure are not limited to toxic waste sites and massive poisoning events. Chronic exposure continues to be a major public health problem worldwide, affecting hundreds of millions of persons. We reviewed recent information on worldwide concerns for arsenic exposures and public health to heighten awareness of the current scope of arsenic exposure and health outcomes and the importance of reducing exposure, particularly during pregnancy and early life. We synthesized the large body of current research pertaining to arsenic exposure and health outcomes with an emphasis on recent publications. Locations of high arsenic exposure via drinking water span from Bangladesh, Chile, and Taiwan to the United States. The U.S. Environmental Protection Agency maximum contaminant level (MCL) in drinking water is 10 µg/L; however, concentrations of > 3,000 µg/L have been found in wells in the United States. In addition, exposure through diet is of growing concern. Knowledge of the scope of arsenic-associated health effects has broadened; arsenic leaves essentially no bodily system untouched. Arsenic is a known carcinogen associated with skin, lung, bladder, kidney, and liver cancer. Dermatological, developmental, neurological, respiratory, cardiovascular, immunological, and endocrine effects are also evident. Most remarkably, early-life exposure may be related to increased risks for several types of cancer and other diseases during adulthood. These data call for heightened awareness of arsenic-related pathologies in broader contexts than previously perceived. Testing foods and drinking water for arsenic, including individual private wells, should be a top priority to reduce exposure, particularly for pregnant women and children, given the potential for life-long effects of developmental exposure.

  11. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    International Nuclear Information System (INIS)

    Elsa Brillaud; Aleksandra Piotrowski; Anthony Lecomte; Franck Robidel; Rene de Seze

    2006-01-01

    Radio frequencies are suspected to produce health effects. Concerning the mobile phone technology, according to position during use (close to the head), possible effects of radio frequencies on the central nervous system have to be evaluated. Previous works showed contradictory results, possibly due to experimental design diversity. In the framework of R.A.M.P. 2001 project, we evaluated possible effect of a 900 MHz GSM exposure on the central nervous system of rat at a structural, a functional and a behavioral level after acute or sub-chronic exposures. Rats were exposed using a loop antenna system to different S.A.R. levels and durations, according to results of the French C.O.M.O.B.I.O. 2001 project. A functional effect was found (modification of the cerebral activity and increase of the glia surface) after an acute exposure, even at a low level of brain averaged S.A.R. (1.5 W/kg). No cumulative effect was observed after a sub-chronic exposure (same amplitude of the effect). No structural or behavioral consequence was noted. We do not conclude on the neurotoxicity of the 900 MHz GSM exposure on the rat brain. Our results do not indicate any health risk. (authors)

  12. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    Energy Technology Data Exchange (ETDEWEB)

    Elsa Brillaud; Aleksandra Piotrowski; Anthony Lecomte; Franck Robidel; Rene de Seze [Toxicology Unit, INERIS, Verneuil en Halatte (France)

    2006-07-01

    Radio frequencies are suspected to produce health effects. Concerning the mobile phone technology, according to position during use (close to the head), possible effects of radio frequencies on the central nervous system have to be evaluated. Previous works showed contradictory results, possibly due to experimental design diversity. In the framework of R.A.M.P. 2001 project, we evaluated possible effect of a 900 MHz GSM exposure on the central nervous system of rat at a structural, a functional and a behavioral level after acute or sub-chronic exposures. Rats were exposed using a loop antenna system to different S.A.R. levels and durations, according to results of the French C.O.M.O.B.I.O. 2001 project. A functional effect was found (modification of the cerebral activity and increase of the glia surface) after an acute exposure, even at a low level of brain averaged S.A.R. (1.5 W/kg). No cumulative effect was observed after a sub-chronic exposure (same amplitude of the effect). No structural or behavioral consequence was noted. We do not conclude on the neurotoxicity of the 900 MHz GSM exposure on the rat brain. Our results do not indicate any health risk. (authors)

  13. Association between type 2 diabetes and chronic arsenic exposure in drinking water: a cross sectional study in Bangladesh.

    Science.gov (United States)

    Islam, Rafiqul; Khan, Ismail; Hassan, Sheikh Nazmul; McEvoy, Mark; D'Este, Catherine; Attia, John; Peel, Roseanne; Sultana, Munira; Akter, Shahnaz; Milton, Abul Hasnat

    2012-06-07

    Chronic exposure to high level of inorganic arsenic in drinking water has been associated with Type 2 Diabetes (T2D). Most research has been ecological in nature and has focused on high levels of arsenic exposure with few studies directly measuring arsenic levels in drinking water as an index of arsenic exposure. The effect of low to moderate levels of arsenic exposure on diabetes risk is largely unknown thus our study is adding further knowledge over previous works. This cross sectional study was conducted in 1004 consenting women and men from 1682 eligible participants yielding a participation rate of 60%. These participants are aged >30 years and were living in Bangladesh and had continuously consumed arsenic-contaminated drinking water for at least 6 months. T2D cases were diagnosed using glucometer following the new diagnostic criteria (Fasting Blood Glucose > 126 mg/dl) from the WHO guideline (WHO 2006), or a self-reported physician diagnosis of type 2 diabetes. Association between T2D and chronic arsenic exposure was estimated by multiple logistic regression with adjustment for age, sex, education, Body Mass Index (BMI) and family history of T2D. A total of 1004 individuals participated in the study. The prevalence of T2D was 9% (95% CI 7-11%). After adjustment for diabetes risk factors, an increased risk of type 2 diabetes was observed for arsenic exposure over 50 μg/L with those in the highest category having almost double the risk of type 2 diabetes (OR=1.9 ; 95% CI 1.1-3.5). For most levels of arsenic exposure, the risk estimates are higher with longer exposure; a dose-response pattern was also observed. These findings suggest an association between chronic arsenic exposure through drinking water and T2D. Risks are generally higher with longer duration of arsenic exposure. The risk of T2D is highest among those who were exposed to the highest concentration of arsenic for more than 10 years.

  14. Quantitative modeling of responses to chronic ionizing radiation exposure using targeted and non-targeted effects.

    Directory of Open Access Journals (Sweden)

    Igor Shuryak

    Full Text Available The biological effects of chronic ionizing radiation exposure can be difficult to study, but important to understand in order to protect the health of occupationally-exposed persons and victims of radiological accidents or malicious events. They include targeted effects (TE caused by ionizations within/close to nuclear DNA, and non-targeted effects (NTE caused by damage to other cell structures and/or activation of stress-signaling pathways in distant cells. Data on radiation damage in animal populations exposed over multiple generations to wide ranges of dose rates after the Chernobyl nuclear-power-plant accident are very useful for enhancing our understanding of these processes. We used a mechanistically-motivated mathematical model which includes TE and NTE to analyze a large published data set on chromosomal aberrations in pond snail (Lymnaea stagnalis embryos collected over 16 years from water bodies contaminated by Chernobyl fallout, and from control locations. The fraction of embryo cells with aberrations increased dramatically (>10-fold and non-linearly over a dose rate range of 0.03-420 μGy/h (0.00026-3.7 Gy/year. NTE were very important for describing the non-linearity of this radiation response: the TE-only model (without NTE performed dramatically worse than the TE+NTE model. NTE were predicted to reach ½ of maximal intensity at 2.5 μGy/h (0.022 Gy/year and to contribute >90% to the radiation response slope at dose rates <11 μGy/h (0.1 Gy/year. Internally-incorporated 90Sr was possibly more effective per unit dose than other radionuclides. The radiation response shape for chromosomal aberrations in snail embryos was consistent with data for a different endpoint: the fraction of young amoebocytes in adult snail haemolymph. Therefore, radiation may affect different snail life stages by similar mechanisms. The importance of NTE in our model-based analysis suggests that the search for modulators of NTE-related signaling pathways

  15. Prospective assessment of chronic multisymptom illness reporting possibly associated with open-air burn pit smoke exposure in Iraq.

    Science.gov (United States)

    Powell, Teresa M; Smith, Tyler C; Jacobson, Isabel G; Boyko, Edward J; Hooper, Tomoko I; Gackstetter, Gary D; Phillips, Christopher J; Smith, Besa

    2012-06-01

    To investigate the relationship between chronic multisymptom illness (CMI) and possible exposure to an open-air burn pit at three selected bases among those deployed to operations in Iraq and Afghanistan. Chronic multisymptom illness (reporting at least one symptom in at least two of the following symptom constructs: general fatigue; mood and cognition problems; and musculoskeletal discomfort) was assessed, differentiating by potential burn pit exposure, among deployers who completed 2004 and 2007 Millennium Cohort questionnaires. More than 21,000 Cohort participants were deployed in support of the current operations, including more than 3000 participants with at least one deployment within a 3-mile radius of a documented burn pit. After adjusting for covariates, no elevated risk of CMI was observed among those exposed. There was no increase in CMI symptom reporting in those deployed to three selected bases with documented burn pits compared with other deployers.

  16. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    Energy Technology Data Exchange (ETDEWEB)

    Kovalchuk, O.; Kovalchuk, I.; Hohn, B. [Friedrich Miescher Institute, P.O. Box 2543, CH-4002 Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research, Shkolnaya Str. 6, 255620 Chernobyl (Ukraine); Barylyak, I.; Karachov, I. [Ukrainian Scientific Genetics Center, Popudrenko Str. 50, 253660 Kiev (Ukraine); Titov, V. [Ivano-Frankivsk State Medical Academy, Galitska Str.2, 284000 Ivano-Frankivsk (Ukraine)

    2000-04-03

    Ionizing radiation (IR) is a known mutagen responsible for causing DNA strand breaks in all living organisms. Strand breaks thus created can be repaired by different mechanisms, including homologous recombination (HR), one of the key mechanisms maintaining genome stability [A. Britt, DNA damage and repair in plants, Annu. Rev. Plant. Phys. Plant Mol. Biol., 45 (1996) 75-100; H. Puchta, B. Hohn, From centiMorgans to basepairs: homologous recombination in plants, Trends Plant Sci., 1 (1996) 340-348.]. Acute or chronic exposure to IR may have different influences on the genome integrity. Although in a radioactively contaminated environment plants are mostly exposed to chronic pollution, evaluation of both kinds of influences is important. Estimation of the frequency of HR in the exposed plants may serve as an indication of genome stability. We used previously generated Arabidopsis thaliana and Nicotiana tabacum plants, transgenic for non-active versions of the {beta}-glucoronidase gene (uidA) [P. Swoboda, S. Gal, B. Hohn, H. Puchta, Intrachromosomal homologous recombination in whole plants, EMBO J., 13 (1994) 484-489; H. Puchta, P. Swoboda, B. Hohn, Induction of homologous DNA recombination in whole plants, Plant, 7 (1995) 203-210.] serving as a recombination substrate, to study the influence of acute and chronic exposure to IR on the level of HR as example of genome stability in plants. Exposure of seeds and seedlings to 0.1 to 10.0 Gy 60Co resulted in increased HR frequency, although the effect was more pronounced in seedlings. For the study of the influence of chronic exposure to IR, plants were grown on two chemically different types of soils, each artificially contaminated with equal amounts of 137Cs. We observed a strong and significant correlation between the frequency of HR in plants, the radioactivity of the soil samples and the doses of radiation absorbed by plants (in all cases r0.9, n=6, P<0.05). In addition, we noted that plants grown in soils with

  17. Employee's perceived exposure to environmental tobacco smoke, passive smoking risk beliefs and attitudes towards smoking: a case study in a university setting.

    Science.gov (United States)

    Duaso, M J; De Irala, J; Canga, N

    2006-02-01

    Despite the growing literature on workplace smoking policies, few studies have focused on the implementation of such policies in university settings. Smoking in the workplace is still very common in many countries, including Spain. While the law is about to change and more non-smoking policies are to be implemented, it is not clear what kind of restrictions Spanish workers would find acceptable. This study investigated perceived exposure to environmental tobacco smoke (ETS), passive smoking risks beliefs and attitudes towards smoking at the University of Navarra (Spain). A questionnaire was sent by E-mail to 641 randomly selected employees and a response rate of 70.4% was obtained. The survey results suggest that 27.3% of the university employees were smokers and 26.6% were exposed to ETS on a daily basis. The majority of respondents (81.7%) supported a restrictive non-smoking policy. Acceptance among active smokers was significantly lower (59.2 versus 89.3%). Smoking prohibition with the provision of smoking areas was the most favored option (46.9%). Results suggest that employees are ready to restrict smoking in the university, but there was not enough support for a total ban. Employers considering adopting a ban on smoking should be encouraged to conduct a similar survey to identify potential barriers to policy implementation.

  18. Some characteristics of the Atomic Energy Organization of Iran (AEOI) passive radon diffusion dosimeter for indoor exposure determination of public in Iran

    International Nuclear Information System (INIS)

    Sohrabi, M.; Solaymanian, A.R.

    1989-01-01

    A Passive Radon diffusion dosimeter (PRDD) was developed at the Radiation Protection Department of the Atomic Energy Organization of Iran (AEOI) for large scale radon level measurements in Iran. It consists of a plastic cup with a polycarbonate alpha detector in the middle, a plastic top cover with an opening holding a fiberglass filter and a hard aluminium mesh for protection and support. A new design of our multi-chamber system was used for multiple foil etching. The effects of pre-etching and ECE times, chamber volume, filter diameter and foil position inside the chamber were investigated. The optimized geometries include 9.5 cm height, 269 cm 3 volume and 2-3 cm filter diameter with the polycarbonate foil mounted in the middle. A sensitivity of 0.05+-0.007 tracks cm -2 /Bq.m -3 day or 1.96+-0.28 tracks cm -2 /pCi.1 -1 day was obtained at optimized conditions. The characteristics of the dosimeter as well as some preliminary results of indoor radon level measurements for determination of public exposure in 250 houses in different cities of Iran including Tehran, Ramsar, Babolsar and Gonabad are presented. The highest radon levels were found in high natural areas of Ramsar

  19. Neutralisation of interleukin-13 in mice prevents airway pathology caused by chronic exposure to house dust mite.

    Directory of Open Access Journals (Sweden)

    Kate L Tomlinson

    Full Text Available BACKGROUND: Repeated exposure to inhaled allergen can cause airway inflammation, remodeling and dysfunction that manifests as the symptoms of allergic asthma. We have investigated the role of the cytokine interleukin-13 (IL-13 in the generation and persistence of airway cellular inflammation, bronchial remodeling and deterioration in airway function in a model of allergic asthma caused by chronic exposure to the aeroallergen House Dust Mite (HDM. METHODOLOGY/PRINCIPAL FINDINGS: Mice were exposed to HDM via the intranasal route for 4 consecutive days per week for up to 8 consecutive weeks. Mice were treated either prophylactically or therapeutically with a potent neutralising anti-IL-13 monoclonal antibody (mAb administered subcutaneously (s.c.. Airway cellular inflammation was assessed by flow cytometry, peribronchial collagen deposition by histocytochemistry and airway hyperreactivity (AHR by invasive measurement of lung resistance (R(L and dynamic compliance (C(dyn. Both prophylactic and therapeutic treatment with an anti-IL-13 mAb significantly inhibited (P<0.05 the generation and maintenance of chronic HDM-induced airway cellular inflammation, peribronchial collagen deposition, epithelial goblet cell upregulation. AHR to inhaled methacholine was reversed by prophylactic but not therapeutic treatment with anti-IL-13 mAb. Both prophylactic and therapeutic treatment with anti-IL-13 mAb significantly reversed (P<0.05 the increase in baseline R(L and the decrease in baseline C(dyn caused by chronic exposure to inhaled HDM. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that in a model of allergic lung disease driven by chronic exposure to a clinically relevant aeroallergen, IL-13 plays a significant role in the generation and persistence of airway inflammation, remodeling and dysfunction.

  20. Concomitant stress potentiates the preference for, and consumption of, ethanol induced by chronic pre-exposure to ethanol

    OpenAIRE

    G. Morais-Silva; J. Fernandes-Santos; D. Moreira-Silva; M.T. Marin

    2016-01-01

    Ethanol abuse is linked to several acute and chronic injuries that can lead to health problems. Ethanol addiction is one of the most severe diseases linked to the abuse of this drug. Symptoms of ethanol addiction include compulsive substance intake and withdrawal syndrome. Stress exposure has an important role in addictive behavior for many drugs of abuse (including ethanol), but the consequences of stress and ethanol in the organism when these factors are concomitant results in a complex int...

  1. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Person, Rachel J.; Olive Ngalame, Ntube N.; Makia, Ngome L.; Bell, Matthew W.; Waalkes, Michael P.; Tokar, Erik J., E-mail: tokare@niehs.nih.gov

    2015-07-01

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  2. Chronic Nicotine Exposure In Vivo and In Vitro Inhibits Vitamin B1 (Thiamin Uptake by Pancreatic Acinar Cells.

    Directory of Open Access Journals (Sweden)

    Padmanabhan Srinivasan

    Full Text Available Thiamin (vitamin B1, a member of the water-soluble family of vitamins, is essential for normal cellular functions; its deficiency results in oxidative stress and mitochondrial dysfunction. Pancreatic acinar cells (PAC obtain thiamin from the circulation using a specific carrier-mediated process mediated by both thiamin transporters -1 and -2 (THTR-1 and THTR-2; encoded by the SLC19A2 and SLC19A3 genes, respectively. The aim of the current study was to examine the effect of chronic exposure of mouse PAC in vivo and human PAC in vitro to nicotine (a major component of cigarette smoke that has been implicated in pancreatic diseases on thiamin uptake and to delineate the mechanism involved. The results showed that chronic exposure of mice to nicotine significantly inhibits thiamin uptake in murine PAC, and that this inhibition is associated with a marked decrease in expression of THTR-1 and THTR-2 at the protein, mRNA and hnRNAs level. Furthermore, expression of the important thiamin-metabolizing enzyme, thiamin pyrophosphokinase (TPKase, was significantly reduced in PAC of mice exposed to nicotine. Similarly, chronic exposure of cultured human PAC to nicotine (0.5 μM, 48 h significantly inhibited thiamin uptake, which was also associated with a decrease in expression of THTR-1 and THTR-2 proteins and mRNAs. This study demonstrates that chronic exposure of PAC to nicotine impairs the physiology and the molecular biology of the thiamin uptake process. Furthermore, the study suggests that the effect is, in part, mediated through transcriptional mechanism(s affecting the SLC19A2 and SLC19A3 genes.

  3. Chronic CO2 exposure markedly increases the incidence of cataracts in juvenile Atlantic cod Gadus morhua L

    DEFF Research Database (Denmark)

    Moran, Damian; Tubbs, Lincoln; Støttrup, Josianne G.

    2012-01-01

    A study was undertaken to test the affect of chronic exposure to elevated dissolved carbon dioxide on juvenile Atlantic cod. The CO2 treatment concentrations were designated as low (1–2mgL−1, 1000μatm), medium (8mgL−1, 3500μatm) and high (18mgL−1, 8500μatm), and the fish were reared at 10°C and 2...

  4. Graded Exposure for Chronic Low Back Pain in Older Adults: A Pilot Study.

    Science.gov (United States)

    Leonhardt, Corinna; Kuss, Katrin; Becker, Annette; Basler, Heinz-Dieter; de Jong, Jeroen; Flatau, Brigitta; Laekeman, Marjan; Mattenklodt, Peter; Schuler, Matthias; Vlaeyen, Johan; Quint, Sabine

    Fear-avoidance beliefs in older adults with chronic low back pain (CLBP) can lead to disability. Graded exposure-based active physical therapy could be an option to enhance physical ability in older patients with CLBP. The purpose of this study was to develop a standardized graded exposure treatment according to the fear-avoidance model of musculoskeletal pain for older patients with CLBP and to examine its effectiveness and feasibility in the German health care system. The study represents a phase I/phase II trial of a complex intervention. Taking a first step into the hierarchy of growing empirical evidence, a prospective 1-factor observational study was conducted with repeated measurements 1 week before and within 2 weeks after the intervention. Three physical therapists, who completed an introductory workshop, provided the treatment in the form of individual therapies. Sixteen participants 65 years or older with CLBP and perceived physical limitations were recruited. Four patient-reported outcome measures and semistructured interviews were conducted. The primary outcome was physical ability measured with the Hanover Functional Ability Questionnaire. Secondary outcomes were the numerical pain rating scale, and an age-specific and adapted 11-item short-form of the Patient Anxiety Symptom Scale, the KVS-D 65+, which quantified catastrophizing and avoidance beliefs. Fear of falling was measured with the Falls Efficacy Scale-International. For the analysis, Wilcoxon signed-rank test for paired samples and an α level of .05 were chosen. For the qualitative evaluation, semistructured interviews were conducted with the patients and physical therapists explored indicators of feasibility such as demands, acceptability, satisfaction, adaptation needs, and implementation. For content analysis, codes were primarily derived deductively and complemented by inductively derived new themes. A significant increase in physical ability after the treatment was observed with an

  5. Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

    Directory of Open Access Journals (Sweden)

    Chien-Yuan Huang

    Full Text Available Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD and identify the related factors.We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD.Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99, female gender (AOR = 1.74, 95%CI: 1.20-2.53, hypertension (AOR = 1.68, 95%CI: 1.17-2.42, high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61, high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20, and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year were independent predictors of CKD.A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

  6. Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

    Science.gov (United States)

    Huang, Chien-Yuan; Wu, Cheng-Long; Wu, Jin-Shang; Chang, Jung-Wei; Cheng, Ya-Yun; Kuo, Yau-Chang; Yang, Yi-Ching; Lee, Ching-Chang; Guo, How-Ran

    2016-01-01

    Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD) and identify the related factors. We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR) ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD. Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99), female gender (AOR = 1.74, 95%CI: 1.20-2.53), hypertension (AOR = 1.68, 95%CI: 1.17-2.42), high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61), high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20), and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year) were independent predictors of CKD. A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

  7. Cytogenetic damage at low doses and the problem of bioindication of chronic low level radiation exposure

    International Nuclear Information System (INIS)

    Geras'kin, S.A.; Dikarev, V.G.; Nesterov, E.B.; Vasiliev, D.V.; Dikareva, N.S.

    2000-01-01

    The analysis undertaken by us of the experimentally observed cellular responses to low dose irradiation has shown that the relationship between the yield of induced cytogenetic damage and radiation dose within low dose range is non-linear and universal in character. Because of the relationship between the yield of cytogenetic damage and dose within low dose range is non-linear, the aberration frequency cannot be used in biological dosimetry in the most important in terms of practical application case. The cytogenetic damage frequency cannot be used in biological dosimetry also because of the probability of synergistic and antagonistic interaction effects of the different nature factors simultaneously acting on test-object in real conditions is high within low dose (concentration) range. In our experimental study of the regularities in the yield of structural mutations in conditions of combined influence of ionizing radiation, heavy metals and pesticides it was found that synergistic and antagonistic effects are mainly induced in conditions of combined action of low exposure injuring agents. Experiments on agricultural plants were carried out in 1986-1989 at the 30-km zone around Chernobyl NPP. It was shown that chronic low dose exposure could cause an inheritable destabilization of genetic structures expressing in increase of cytogenetic damage and yield karyotypic variability in offspring's of irradiated organisms. Obviously exactly this circumstance is the reason of the phenomenon found in our researches of significant time delay of cytogenetic damage reduction rate from radioactive pollution reduction rate from time past from the accident moment. Research of cytogenetic damage of reproductive (seeds) and vegetative (needles) plant organs of the Pinus sylvestris tree micropopulations growing in contrast by radioactive pollution level sites of the 30-km ChNPP zone and also in the vicinity of the industrial plant > for processing and temporary storage of

  8. PROVANN: Model System for Chronic Exposure of Larval and Adult Fish to Releases from Offshore Petroleum Platforms

    International Nuclear Information System (INIS)

    Reed, M.; Rye, H.; Melbye, A.; Johnsen, S.

    1996-01-01

    Produced water from offshore oil and gas production platforms contains a variety of hydrocarbons, heavy metals, and production chemicals. Vertical and horizontal mixing generally brings concentrations in discharge plumes below level associated with acute effects within 500 or 1000 m of the source. Chronic effects outside this region remain a potential problem. The purpose of PROVANN, the system of models described in this paper, is to assess the potential for chronic effects from produced water. The preliminary focus is on potential bioaccumulation and boimagnification of produced water constituents in the marine food web. Other possible types of chronic effects, such as reduced fecundity, or pheromone response interference, can also be assessed to the extent that such effects may be correlated with exposure. PROVANN simulates 3-dimensional transport, dilution, and degradation of chemicals released into the water, from one or more simultaneous sources. 8 refs., 10 figs., 3 tabs

  9. Passive Education

    Science.gov (United States)

    Bojesen, Emile

    2018-01-01

    This paper does not present an advocacy of a passive education as opposed to an active education nor does it propose that passive education is in any way 'better' or more important than active education. Through readings of Maurice Blanchot, Jacques Derrida and B.S. Johnson, and gentle critiques of Jacques Rancière and John Dewey, passive…

  10. Chronic exposure to dopamine agonists affects the integrity of striatal D2 receptors in Parkinson's patients

    Directory of Open Access Journals (Sweden)

    Marios Politis

    2017-01-01

    Full Text Available We aimed to investigate the integrity and clinical relevance of striatal dopamine receptor type-2 (D2R availability in Parkinson's disease (PD patients. We studied 68 PD patients, spanning from early to advanced disease stages, and 12 healthy controls. All participants received one [11C]raclopride PET scan in an OFF medication condition for quantification of striatal D2R availability in vivo. Parametric images of [11C]raclopride non-displaceable binding potential were generated from the dynamic [11C]raclopride scans using implementation of the simplified reference tissue model with cerebellum as the reference tissue. PET data were interrogated for correlations with clinical data related to disease burden and dopaminergic treatment. PD patients showed a mean 16.7% decrease in caudate D2R and a mean 3.5% increase in putaminal D2R availability compared to healthy controls. Lower caudate [11C]raclopride BPND correlated with longer PD duration. PD patients on dopamine agonist treatment had 9.2% reduced D2R availability in the caudate and 12.8% in the putamen compared to PD patients who never received treatment with dopamine agonists. Higher amounts of lifetime dopamine agonist therapy correlated with reduced D2Rs availability in both caudate and putamen. No associations between striatal D2R availability and levodopa treatment and dyskinesias were found. In advancing PD the caudate and putamen D2R availability are differentially affected. Chronic exposure to treatment with dopamine agonists, but no levodopa, suppresses striatal D2R availability, which may have relevance to output signaling to frontal lobes and the occurrence of executive deficits, but not dyskinesias.

  11. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season

  12. Effect of chronic pesticide exposure in farm workers of a Mexico community.

    Science.gov (United States)

    Payán-Rentería, Rolando; Garibay-Chávez, Guadalupe; Rangel-Ascencio, Raul; Preciado-Martínez, Veronica; Muñoz-Islas, Laura; Beltrán-Miranda, Claudia; Mena-Munguía, Salvador; Jave-Suárez, Luis; Feria-Velasco, Alfredo; De Celis, Ruth

    2012-01-01

    Pesticides are frequently used substances worldwide, even when the use of some of them is forbidden due to the recognized adverse effect they have on the health of not only the people who apply the pesticides, but also of those that consume the contaminated products. The objectives of this study were to know the health issues of farm workers chronically exposed to pesticides, to evaluate possible damage at genetic level, as well as to explore some hepatic, renal, and hematological alterations. A transversal comparative study was performed between 2 groups, one composed of 25 farm workers engaged in pesticide spraying, and a control group of 21 workers not exposed to pesticides; both groups belonged to the Nextipac community in Jalisco, Mexico. Each member of both groups underwent a full medical history. Blood samples were taken from all farm workers in order to obtain a complete blood count and chemistry, clinical chemistry, lipid profile, liver and kidney function tests, erythrocyte cholinesterase quantification, lipid peroxidation profile, and free DNA fragment quantification. For the information analysis, central tendency and dispersion measurements were registered. In order to know the differences between groups, a cluster multivariate method was used, as well as prevalence reasons. The most used pesticides were mainly organophosphates, triazines and organochlorine compounds. The exposed group showed acute poisoning (20% of the cases) and diverse alterations of the digestive, neurological, respiratory, circulatory, dermatological, renal, and reproductive system probably associated to pesticide exposure. More importantly, they presented free DNA fragments in plasma (90.8 vs 49.05 ng/mL) as well as a higher level of lipid peroxidation (41.85 vs. 31.91 nmol/mL) in comparison with those data from unexposed farm workers. These results suggest that there exist health hazards for those farm workers exposed to pesticides, at organic and cellular levels.

  13. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C; Johnson, J.D; Rollstin, J.A; Shiver, A.W; Sprung, J.L

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, water ingestion dose, milk growing-season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meet, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of I-131 at which disposal of crops will be initiated due to accidents that occur during the growing season. Reducing the uncertainty in the preceding variables was found to substantially reduce the uncertainty in the

  14. Reproductive toxicity in rats after chronic oral exposure to low dose of depleted uranium

    International Nuclear Information System (INIS)

    Li Rong; Ai Guoping; Xu Hui; Su Yongping; Cheng Tianmin; Leng Yanbing

    2007-01-01

    Objective: To study the reproductive toxicity in rats induced by low dose of depleted uranium (DU). Methods: Male and female rats(F 0 generation) were exposed to DU in food at doses of 0, 0.4, 4 and 40 mg·kg -1 ·d -1 for 160 days, respectively. Then the activities of enzymes in testis and sexual hormone contents in serum were detected. Mature male rats were mated with female rats exposed to the same doses for 14 days. Pregnant rate and normal labor rate in F 0 rats were detected, as well as the survival rate and weight of F 1 rats within 21 d after birth. Results: No adverse effects of DU on fertility were evident at any dose in F 0 rats. Compared with control group, the rate of pregnancy, normal labor, survival of offspring birth and offspring nurture in F 1 generation of high-dose group reduced to 40.0%, 33.3%, 33.3%, and 33.3%, respectively. The sexual hormone contents in F 0 generation exposed increased, but those in Fl rats decreased significantly. The activities of lactate dehydrogenase-X (LDH-X) decreased in F 1 rats exposed to high-dose of DU, and those of sorbitol dehydrogenase (SDH), LDH and Na + -K + -ATPase decreased in F 1 rats exposed to DU. Conclusions: Reproduction function, growth and development of F 0 rats are not obviously affected after chronic oral exposure to DU, while the toxicity effects in F 1 generation was observed at any dose. (authors)

  15. Effect of low and chronic radiation exposure to human population: Kollam study

    International Nuclear Information System (INIS)

    Ghosh, Anu; Kumar, Vinay

    2018-01-01

    Understanding the cellular and biological processes with low-level chronic radiation provides a rational basis for limits of exposure for occupational workers and general public. There are several high level natural radiation areas (HLNRA) of the world where human population is continuously exposed to natural radiation higher than the global average of 2.4 mGy/y. These areas provide unique opportunities to conduct studies which can provide better understanding of radiation effects and underlying mechanisms. The ∼55 km long monazite bearing belt of Kerala on the south-west coast of India is one such area. Over the last few decades, Bhabha Atomic Research Centre (BARC) has conducted extensive research on the human population residing in these areas to understand effects of low dose at the organismal, cellular and molecular levels. More recently, high resolution quantitative proteomic analysis of PBMCs using iTRAQ based LC-MS/MS identified differential expression of 1570 proteins in HLNRA individuals relative to individuals from the adjoining Normal Level Natural Radiation Areas (NLNRA). Almost 215 biological processes were distinctly altered in HLNRA samples, which included several pro-survival stress activated protein kinases and DNA repair networks. Many of the changes seen at the proteomics level were confirmed at the gene level using microarray expression data. This suggests an enhanced level of basal repair mechanisms in HLNRA individuals. The scientific program at BARC thus, focuses on fundamental scientific understanding of the mechanisms cells use to sense, repair and adapt to low dose radiation. Implications of these cellular processes for low dose radiation risk estimation will be discussed. (author)

  16. Short-term exposure to enriched environment rescues chronic stress-induced impaired hippocampal synaptic plasticity, anxiety, and memory deficits.

    Science.gov (United States)

    Bhagya, Venkanna Rao; Srikumar, Bettadapura N; Veena, Jayagopalan; Shankaranarayana Rao, Byrathnahalli S

    2017-08-01

    Exposure to prolonged stress results in structural and functional alterations in the hippocampus including reduced long-term potentiation (LTP), neurogenesis, spatial learning and working memory impairments, and enhanced anxiety-like behavior. On the other hand, enriched environment (EE) has beneficial effects on hippocampal structure and function, such as improved memory, increased hippocampal neurogenesis, and progressive synaptic plasticity. It is unclear whether exposure to short-term EE for 10 days can overcome restraint stress-induced cognitive deficits and impaired hippocampal plasticity. Consequently, the present study explored the beneficial effects of short-term EE on chronic stress-induced impaired LTP, working memory, and anxiety-like behavior. Male Wistar rats were subjected to chronic restraint stress (6 hr/day) over a period of 21 days, and then they were exposed to EE (6 hr/day) for 10 days. Restraint stress reduced hippocampal CA1-LTP, increased anxiety-like symptoms in elevated plus maze, and impaired working memory in T-maze task. Remarkably, EE facilitated hippocampal LTP, improved working memory performance, and completely overcame the effect of chronic stress on anxiety behavior. In conclusion, exposure to EE can bring out positive effects on synaptic plasticity in the hippocampus and thereby elicit its beneficial effects on cognitive functions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Chronic intermittent ethanol exposure and withdrawal leads to adaptations in nucleus accumbens core postsynaptic density proteome and dendritic spines.

    Science.gov (United States)

    Uys, Joachim D; McGuier, Natalie S; Gass, Justin T; Griffin, William C; Ball, Lauren E; Mulholland, Patrick J

    2016-05-01

    Alcohol use disorder is a chronic relapsing brain disease characterized by the loss of ability to control alcohol (ethanol) intake despite knowledge of detrimental health or personal consequences. Clinical and pre-clinical models provide strong evidence for chronic ethanol-associated alterations in glutamatergic signaling and impaired synaptic plasticity in the nucleus accumbens (NAc). However, the neural mechanisms that contribute to aberrant glutamatergic signaling in ethanol-dependent individuals in this critical brain structure remain unknown. Using an unbiased proteomic approach, we investigated the effects of chronic intermittent ethanol (CIE) exposure on neuroadaptations in postsynaptic density (PSD)-enriched proteins in the NAc of ethanol-dependent mice. Compared with controls, CIE exposure significantly changed expression levels of 50 proteins in the PSD-enriched fraction. Systems biology and functional annotation analyses demonstrated that the dysregulated proteins are expressed at tetrapartite synapses and critically regulate cellular morphology. To confirm this latter finding, the density and morphology of dendritic spines were examined in the NAc core of ethanol-dependent mice. We found that CIE exposure and withdrawal differentially altered dendrite diameter and dendritic spine density and morphology. Through the use of quantitative proteomics and functional annotation, these series of experiments demonstrate that ethanol dependence produces neuroadaptations in proteins that modify dendritic spine morphology. In addition, these studies identified novel PSD-related proteins that contribute to the neurobiological mechanisms of ethanol dependence that drive maladaptive structural plasticity of NAc neurons. © 2015 Society for the Study of Addiction.

  18. Yohimbine reinstates extinguished 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) seeking in rats with prior exposure to chronic yohimbine.

    Science.gov (United States)

    Ball, Kevin T; Jarsocrak, Hanna; Hyacinthe, Johanna; Lambert, Justina; Lockowitz, James; Schrock, Jordan

    2015-11-01

    Although exposure to acute stress has been shown to reinstate extinguished responding for a wide variety of drugs, no studies have investigated stress-induced reinstatement in animals with a history of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) self-administration. Thus, rats were trained to press a lever for MDMA (0.50 mg/kg/infusion) in daily sessions, and lever pressing was subsequently extinguished in the absence of MDMA and conditioned cues (light and tone). We then tested the ability of acute yohimbine (2.0 mg/kg), a pharmacological stressor, to reinstate lever-pressing under extinction conditions. Additionally, to model chronic stress, some rats were injected daily with yohimbine (5.0 mg/kg × 10 days) prior to reinstatement tests. To assess dopaminergic involvement, chronic yohimbine injections were combined with injections of SCH-23390 (0.0 or 10.0 μg/kg), a dopamine D1-like receptor antagonist. In a separate experiment, rats with a history of food self-administration were treated and tested in the same way. Results showed that acute yohimbine injections reinstated extinguished MDMA and food seeking, but only in rats with a history of chronic yohimbine exposure. Co-administration of SCH-23390 with chronic yohimbine injections prevented the potentiation of subsequent food seeking, but not MDMA seeking. These results suggest that abstinent MDMA users who also are exposed to chronic stress may be at increased risk for future relapse, and also that the effects of chronic stress on relapse may be mediated by different mechanisms depending on one's drug use history. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Can chronic exposure to imidacloprid, clothianidin, and thiamethoxam mixtures exert greater than additive toxicity in Chironomus dilutus?

    Science.gov (United States)

    Maloney, E M; Morrissey, C A; Headley, J V; Peru, K M; Liber, K

    2018-07-30

    Widespread agricultural use of neonicotinoid insecticides has resulted in frequent detection of mixtures of these compounds in global surface waters. Recent evidence suggests that neonicotinoid mixtures can elicit synergistic toxicity in aquatic insects under acute exposure conditions, however this has not been validated for longer exposures more commonly encountered in the environment. Therefore, we aimed to characterize the chronic (28-day) toxicity of imidacloprid, clothianidin, and thiamethoxam mixtures under different doses and mixture ratios to determine if the assumption of synergistic toxicity would hold under more environmentally realistic exposure settings. The sensitive aquatic insect Chironomus dilutus was used as a representative test species, and successful emergence was used as a chronic endpoint. Applying the MIXTOX modeling approach, predictive parametric models were fitted using single-compound toxicity data and statistically compared to observed toxicity in subsequent mixture tests. Imidacloprid-clothianidin, clothianidin-thiamethoxam and imidacloprid-clothianidin-thiamethoxam mixtures did not significantly deviate from concentration-additive toxicity. However, the cumulative toxicity of the imidacloprid-thiamethoxam mixture deviated from the concentration-additive reference model, displaying dose-ratio dependent synergism and resulting in up to a 10% greater reduction in emergence from that predicted by concentration addition. Furthermore, exposure to select neonicotinoid mixtures above 1.0 toxic unit tended to shift sex-ratios toward more male-dominated populations. Results indicate that, similar to acute exposures, the general assumption of joint additivity cannot adequately describe chronic cumulative toxicity of all neonicotinoid mixtures. Indeed, our observations of weak synergism and sex-ratio shifts elicited by some mixture combinations should be considered in water quality guideline development and environmental risk assessment practices

  20. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    International Nuclear Information System (INIS)

    Liu, Qing; Rise, Matthew L.; Spitsbergen, Jan M.; Hori, Tiago S.; Mieritz, Mark; Geis, Steven; McGraw, Joseph E.; Goetz, Giles; Larson, Jeremy; Hutz, Reinhold J.; Carvan, Michael J.

    2013-01-01

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  1. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qing [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States); Rise, Matthew L. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Spitsbergen, Jan M. [Department of Microbiology, Oregon State University, 220 Nash Hall, Corvallis, OR 97331 (United States); Hori, Tiago S. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Mieritz, Mark; Geis, Steven [Wisconsin State Laboratory of Hygiene, 465 Henry Mall, Madison, WI 53706 (United States); McGraw, Joseph E. [School of Pharmacy, Concordia University Wisconsin, 12800 North Lake Shore Drive, Mequon, WI 53097 (United States); Goetz, Giles [School of Aquatic and Fishery Sciences, University of Washington, 1122 Northeast Boat Street, Seattle, WA 98195 (United States); Larson, Jeremy; Hutz, Reinhold J. [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); Carvan, Michael J., E-mail: carvanmj@uwm.edu [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States)

    2013-09-15

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  2. 5-lipoxygenase activation is involved in the mechanisms of chronic hepatic injury in a rat model of chronic aluminum overload exposure

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Shaoshan [Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016 (China); He, Qin [Department of Heptobiliary Surgery, 1st Affiliated Hospital, Chongqing Medical University, Chongqing 400016 (China); Wang, Hong; Hu, Xinyue; Luo, Ying; Yang, Yang; Kuang, Shengnan; Tian, Xiaoyan; Ma, Jie [Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016 (China); Yang, Junqing, E-mail: 1139627371@qq.com [Department of Pharmacology, Chongqing Medical University, Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016 (China)

    2016-08-15

    We previously confirmed that rats overloaded with aluminum exhibited hepatic function damage and increased susceptibility to hepatic inflammation. However, the mechanism of liver toxicity by chronic aluminum overload is poorly understood. In this study, we investigated changes in the 5-lipoxygenase (5-LO) signaling pathway and its effect on liver injury in aluminum-overloaded rats. A rat hepatic injury model of chronic aluminum injury was established via the intragastric administration of aluminum gluconate (Al{sup 3+} 200 mg/kg per day, 5 days a week for 20 weeks). The 5-LO inhibitor, caffeic acid (10 and 30 mg/kg), was intragastrically administered 1 h after aluminum administration. Hematoxylin and eosin staining was used to visualize pathological changes in rat liver tissue. A series of biochemical indicators were measured with biochemistry assay or ELISAs. Immunochemistry and RT-PCR methods were used to detect 5-LO protein and mRNA expression in the liver, respectively. Caffeic acid administration protected livers against histopathological injury, decreased plasma ALT, AST, and ALP levels, decreased TNF-α, IL-6, IL-1β and LTs levels, increased the reactive oxygen species content, and down-regulated the mRNA and protein expressions of 5-LO in aluminum overloaded rats. Our results indicate that 5-lipoxygenase activation is mechanistically involved in chronic hepatic injury in a rat model of chronic aluminum overload exposure and that the 5-LO signaling pathway, which associated with inflammation and oxidative stress, is a potential therapeutic target for chronic non-infection liver diseases. - Highlights: • 5-LO signaling contributes to mechanisms of hepatotoxicity of aluminum overload. • Oxidative and inflammatory reaction involve in chonic aluminum hepatotoxicity. • 5-LO inhibitor has a protective effect on aluminum-overload liver injury. • 5-LO signaling is a potential therapeutic target for non-infection liver diseases.

  3. PARAMETER EVALUATION AND MODEL VALIDATION OF OZONE EXPOSURE ASSESSMENT USING HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    To examine factors influencing long-term ozone exposures by children living in urban communities, we analyzed longitudinal data on personal, indoor, and outdoor ozone concentrations as well as related housing and other questionnaire information collected in the one-year-long Harv...

  4. Chronic Exposure to Deoxynivalenol Has No Influence on the Oral Bioavailability of Fumonisin B1 in Broiler Chickens

    Science.gov (United States)

    Antonissen, Gunther; Devreese, Mathias; Van Immerseel, Filip; De Baere, Siegrid; Hessenberger, Sabine; Martel, An; Croubels, Siska

    2015-01-01

    Both deoxynivalenol (DON) and fumonisin B1 (FB1) are common contaminants of feed. Fumonisins (FBs) in general have a very limited oral bioavailability in healthy animals. Previous studies have demonstrated that chronic exposure to DON impairs the intestinal barrier function and integrity, by affecting the intestinal surface area and function of the tight junctions. This might influence the oral bioavailability of FB1, and possibly lead to altered toxicity of this mycotoxin. A toxicokinetic study was performed with two groups of 6 broiler chickens, which were all administered an oral bolus of 2.5 mg FBs/kg BW after three-week exposure to either uncontaminated feed (group 1) or feed contaminated with 3.12 mg DON/kg feed (group 2). No significant differences in toxicokinetic parameters of FB1 could be demonstrated between the groups. Also, no increased or decreased body exposure to FB1 was observed, since the relative oral bioavailability of FB1 after chronic DON exposure was 92.2%. PMID:25690690

  5. Occupational exposure to respirable crystalline silica and chronic non-malignant renal disease: systematic review and meta-analysis.

    Science.gov (United States)

    Möhner, Matthias; Pohrt, Anne; Gellissen, Johannes

    2017-10-01

    While occupational exposure to respirable silica is known to lead to lung disease, most notably silicosis, its association with chronic kidney disease is unclear. This review explores the association between occupational exposure to respirable silica and chronic non-malignant renal disease such as glomerulonephritis. The evidence has been collected and compiled. Possible sources of bias are thoroughly discussed. Cohort studies with silica exposure and case-control studies of renal disease were searched in PubMed until January 2015. Two authors independently abstracted data; any disagreement was resolved by consulting a third reviewer. A meta-analysis was performed to evaluate the association to silica exposure. A total of 23 cohort and four case-control studies were included in the analysis. The meta-analysis of cohort studies yielded elevated overall SMRs for renal disease. Some studies, however, included dose-response analyses, most of which did not show a positive trend. The approaches and results of the case-control studies were very heterogeneous. While the studies of cohorts exposed to silica found elevated SMRs for renal disease, no clear evidence of a dose-response relationship emerged. The elevated risk may be attributed to diagnostic and methodological issues. In order to permit a reliable estimation of a possible causal link, exposed cohorts should be monitored for renal disease, as the information from mortality studies is hardly reliable in this field.

  6. Work-Related Noise Exposure in a Cohort of Patients with Chronic Tinnitus: Analysis of Demographic and Audiological Characteristics

    Directory of Open Access Journals (Sweden)

    Massimo Ralli

    2017-09-01

    Full Text Available Work-related noise exposure is one of the major factors contributing to the development of adult-onset hearing loss and tinnitus. The aim of this study was to analyze, in patients with chronic tinnitus and long-term occupational noise exposure, (A characteristics of hearing loss, tinnitus, comorbidities, demographic characteristics and a history of work-related noise exposure and (B differences among individuals employed in occupations with high and low risk of developing work-related noise-induced hearing loss (NIHL. One hundred thirty six patients with chronic tinnitus and at least a 10 year-long working history were divided into two groups based on the risk of their profession to induce NIHL. Individuals employed in jobs at high risk for NIHL were mostly males and exhibited a poorer hearing threshold, more evident in the left ear. Tinnitus was mostly bilateral; the next largest presentation was left-sided; patients described their tinnitus as buzzing or high-pitched. Correlation between age, length of tinnitus and worse hearing was found. Patients with a higher degree of hearing impairment were mostly males and were more likely to have a family history of hearing loss and at least one cardiovascular comorbidity. Our study shows some differences in individuals with tinnitus and a history of a profession associated with increased exposure to NIHL compared to those without such a history.

  7. Work-Related Noise Exposure in a Cohort of Patients with Chronic Tinnitus: Analysis of Demographic and Audiological Characteristics.

    Science.gov (United States)

    Ralli, Massimo; Balla, Maria Paola; Greco, Antonio; Altissimi, Giancarlo; Ricci, Pasquale; Turchetta, Rosaria; de Virgilio, Armando; de Vincentiis, Marco; Ricci, Serafino; Cianfrone, Giancarlo

    2017-09-08

    Work-related noise exposure is one of the major factors contributing to the development of adult-onset hearing loss and tinnitus. The aim of this study was to analyze, in patients with chronic tinnitus and long-term occupational noise exposure, (A) characteristics of hearing loss, tinnitus, comorbidities, demographic characteristics and a history of work-related noise exposure and (B) differences among individuals employed in occupations with high and low risk of developing work-related noise-induced hearing loss (NIHL). One hundred thirty six patients with chronic tinnitus and at least a 10 year-long working history were divided into two groups based on the risk of their profession to induce NIHL. Individuals employed in jobs at high risk for NIHL were mostly males and exhibited a poorer hearing threshold, more evident in the left ear. Tinnitus was mostly bilateral; the next largest presentation was left-sided; patients described their tinnitus as buzzing or high-pitched. Correlation between age, length of tinnitus and worse hearing was found. Patients with a higher degree of hearing impairment were mostly males and were more likely to have a family history of hearing loss and at least one cardiovascular comorbidity. Our study shows some differences in individuals with tinnitus and a history of a profession associated with increased exposure to NIHL compared to those without such a history.

  8. Novel Pharmacological Approaches for Treatment of Neurotoxicity Induced by Chronic Exposure to Depleted Uranium

    National Research Council Canada - National Science Library

    Lasley, Stephen M

    2008-01-01

    .... This hypothesis is consistent with previous observations ensuing from chronic intramuscular DU pellet implants in rats, and is based on the anticipation that specific pharmacological agents will...

  9. Traumatic Exposure History as a Risk Factor for Chronic Pain in Adult Patients with Sickle Cell Disease.

    Science.gov (United States)

    Works, Teresa; Jones, Sasia; Grady, James; Andemariam, Biree

    2016-02-01

    This article describes the impact of the integration of a licensed clinical social worker (LCSW) with expertise in behavioral health on identification of risk factors for chronic pain in a cohort of adults with sickle cell disease. Authors conducted a retrospective chart review of all visits to the adult sickle cell center during the first six months of LCSW integration. Demographics, clinical history, and LCSW notes were reviewed. Overall, 71 patients were introduced to the LCSW; 55 percent of them had chronic pain. Patients with chronic pain were older, used opioids daily, took hydroxyurea, reported higher daily pain scores, and underwent more acute care visits and hospitalizations for pain with longer stays. Fifty-eight (81 percent) patients requested concrete social work services such as transportation and housing. Thirty-two patients (55 percent) expressed a desire for mental health counseling while receiving concrete services. Twenty-two (69 percent) of these patients self-disclosed at least one traumatic experience. In fact, a statistically significant relationship between chronic pain and a history of trauma was identified (p = 0.001). Results suggest that sickle cell patients should receive clinical social work services to assess for traumatic exposures that may influence chronic pain.

  10. Chronic myelogenous leukemia (CML)

    Science.gov (United States)

    CML; Chronic myeloid leukemia; Chronic granulocytic leukemia; Leukemia - chronic granulocytic ... nuclear disaster. It takes many years to develop leukemia from radiation exposure. Most people treated for cancer ...

  11. How do macro-level contexts and policies affect the employment chances of chronically ill and disabled people? Part II: The impact of active and passive labor market policies

    DEFF Research Database (Denmark)

    Holland, Paula; Nylén, Lotta; Thielen, Karsten

    2011-01-01

    level for men and women in Canada, Denmark, Norway, Sweden, and the United Kingdom, countries with advanced social welfare systems and universal health care but with varying types of active and passive labor market policies. People with chronic illness were found to fare better in employment terms...... in the Nordic countries than in Canada or the United Kingdom. Their employment chances also varied by educational level and country. The employment impact of having both chronic illness and low education was not just additive but synergistic. This amplification was strongest for British men and women, Norwegian...... men, and Danish women. Hypotheses on the disincentive effects of tighter employment regulation or more generous welfare benefits were not supported. The hypothesis that greater investments in active labor market policies may improve the employment of chronically ill people was partially supported...

  12. Effects of sub-chronic exposure to SO{sub 2} on lipid and carbohydrate metabolism in rats

    Energy Technology Data Exchange (ETDEWEB)

    Lovati, M.R. [Institute of Pharmacological Sciences, Milan (Italy); Manzoni, C. [Institute of Pharmacological Sciences, Milan (Italy); Daldossi, M. [Institute of Pharmacological Sciences, Milan (Italy); Spolti, S. [Institute of Pharmacological Sciences, Milan (Italy); Sirtori, C.R. [Institute of Pharmacological Sciences, Milan (Italy)

    1996-01-01

    Sulfur dioxide (SO{sub 2}) is a ubiquitous air pollutant, present in low concentrations in the urban air, and in higher concentrations in the working environment. While toxicological reports on SO{sub 2} have extensively dealt with the pulmonary system, essentially no data are available on the effects of chronic exposure to this pollutant on intermediary metabolism, although some biochemical changes in lipid metabolism have been detected. The present investigation was aimed at evaluating the effects of sub-chronic exposure to SO{sub 2} on concentrations of serum lipids/lipoproteins and on glucose metabolism, in animal models of hypercholesterolemia and diabetes. A specially designed controlinert atmosphere chamber was used, where male Sprague-Dawley rats fed on either standard or cholesterol enriched (HC) diets, as well as streptozotocin diabetics, were exposed to SO{sub 2} at 5 and 10 ppm, 24 h per day for 14 days. In rats, both on a standard diet and on a HC regimen, SO{sub 2} exposure determined a significant dose-dependent increase in plasma triglycerides, up to +363% in the 10 ppm HC exposed animals. This same gas concentration significantly reduced HDL cholesterol levels. In contrast, exposure of diabetic animals to 10 ppm SO{sub 2} resulted in a fall (-41%) of plasma and liver triglycerides and in a concomitant increase (+62%) of plasma HDL cholesterol. This discrepancy could apparently be related to diverging effects of SO{sub 2} exposure on plasma insulin levels in the different animal groups. Kinetic analyses of triglyceride synthesis carried out in rats on a standard diet revealed, in exposed animals, a significant reduction in the secretory rate, in spite of the concomitant hypertriglyceridemia. These findings suggest that SO{sub 2} exposure can markedly modify major lipid and glycemic indices, also indicating a differential response in normo/hyperlipidemic versus diabetic animals. (orig.)

  13. Impact of antigenic exposures and role of molecular blood grouping in enhancing transfusion safety in chronically transfused thalassemics.

    Science.gov (United States)

    Makroo, Raj Nath; Agrawal, Soma; Bhatia, Aakanksha; Chowdhry, Mohit; Thakur, Uday Kumar

    2016-01-01

    Red cell alloimmunization is an acknowledged complication of blood transfusion. Current transfusion practices for thalassemia do not cater to this risk. Serological phenotyping is usually not reliable in these cases unless performed before the first transfusion. Under such circumstances, molecular blood grouping is an effective alternative. To perform molecular blood group genotyping in chronically transfused thalassemia patients and assess the risk of antigenic exposure and incidence of alloimmunization with current transfusion protocols. Molecular blood group genotyping was performed for 47 chronically transfused thalassemia patients. Their 1-year transfusion records were retrieved to assess the antigenic exposure and the frequency thereof. Of 47 patients, 6 were already alloimmunized (3 with anti-E and 3 with anti-K) and were receiving the corresponding antigen negative units. We observed that random selection of ABO and Rh D matched units resulted in 57.7% ±8.26% chance of Rh and Kell phenotype matching also. Forty-four patients had received one or more antigenic exposures at least once. The 6 already alloimmunized patients were further exposed to antigens other than the ones they were immunized to. During the study period, only one patient developed an alloantibody, anti-E with exposure to antigens C (92%) and/or E (32%) at each transfusion. Several factors apart from mere antigen exposure may influence the development of alloimmunization as most of our patients received antigenic exposures but not alloimmunized. Our data provide an impetus for future large-scale studies to understand the development of alloimmunization in such patients.

  14. Impact of antigenic exposures and role of molecular blood grouping in enhancing transfusion safety in chronically transfused thalassemics

    Directory of Open Access Journals (Sweden)

    Raj Nath Makroo

    2016-01-01

    Full Text Available Background: Red cell alloimmunization is an acknowledged complication of blood transfusion. Current transfusion practices for thalassemia do not cater to this risk. Serological phenotyping is usually not reliable in these cases unless performed before the first transfusion. Under such circumstances, molecular blood grouping is an effective alternative. Aim: To perform molecular blood group genotyping in chronically transfused thalassemia patients and assess the risk of antigenic exposure and incidence of alloimmunization with current transfusion protocols. Materials and Methods: Molecular blood group genotyping was performed for 47 chronically transfused thalassemia patients. Their 1-year transfusion records were retrieved to assess the antigenic exposure and the frequency thereof. Results: Of 47 patients, 6 were already alloimmunized (3 with anti-E and 3 with anti-K and were receiving the corresponding antigen negative units. We observed that random selection of ABO and Rh D matched units resulted in 57.7% ±8.26% chance of Rh and Kell phenotype matching also. Forty-four patients had received one or more antigenic exposures at least once. The 6 already alloimmunized patients were further exposed to antigens other than the ones they were immunized to. During the study period, only one patient developed an alloantibody, anti-E with exposure to antigens C (92% and/or E (32% at each transfusion. Conclusion: Several factors apart from mere antigen exposure may influence the development of alloimmunization as most of our patients received antigenic exposures but not alloimmunized. Our data provide an impetus for future large-scale studies to understand the development of alloimmunization in such patients.

  15. The independent role of prenatal and postnatal exposure to active and passive smoking on the development of early wheeze in children

    DEFF Research Database (Denmark)

    Vardavas, C. I.; Hohmann, C; Patelarou, Evridiki

    2016-01-01

    Maternal smoking during pregnancy increases childhood asthma risk, but health effects in children of nonsmoking mothers passively exposed to tobacco smoke during pregnancy are unclear. We examined the association of maternal passive smoking during pregnancy and wheeze in children aged ≤2 years. I...

  16. NEUROCHEMICAL EFFECTS OF CHRONIC DIETARY AND REPEATED HIGH-LEVEL ACUTE EXPOSURE TO CHLORPYRIFOS IN RATS.

    Science.gov (United States)

    Lots of information is available surrounding the acute toxicity of anticholinesterase pesticides, but these have been very few detailed studies on the chronic effects of these pesticides. Humans are exposed on a chronic basis and some humans believe that have been affected advers...

  17. Aflatoxin exposure may contribute to chronic hepatomegaly in Kenyan school children

    DEFF Research Database (Denmark)

    Gong, Yun Yun; Wilson, Shona; Mwatha, Joseph K

    2012-01-01

    Presentation with a firm type of chronic hepatomegaly of multifactorial etiology is common among school-age children in sub-Saharan Africa.......Presentation with a firm type of chronic hepatomegaly of multifactorial etiology is common among school-age children in sub-Saharan Africa....

  18. Hair analysis following chronic smoked-drugs-of-abuse exposure in adults and their toddler: a case report

    Directory of Open Access Journals (Sweden)

    Papaseit Esther

    2011-12-01

    Full Text Available Abstract Introduction Over the past two decades, the study of chronic cocaine and crack cocaine exposure in the pediatric population has been focused on the potential adverse effects, especially in the prenatal period and early childhood. Non-invasive biological matrices have become an essential tool for the assessment of a long-term history of drug of abuse exposure. Case report We analyze the significance of different biomarker values in hair after chronic crack exposure in a two-year-old Caucasian girl and her parents, who are self-reported crack smokers. The level of benzoylecgonine, the principal metabolite of cocaine, was determined in segmented hair samples (0 cm to 3 cm from the scalp, and > 3 cm from the scalp following washing to exclude external contamination. Benzoylecgonine was detectable in high concentrations in the child's hair, at 1.9 ng/mg and 7.04 ng/mg, respectively. Benzoylecgonine was also present in the maternal and paternal hair samples at 7.88 ng/mg and 6.39 ng/mg, and 13.06 ng/mg and 12.97 ng/mg, respectively. Conclusion Based on the data from this case and from previously published poisoning cases, as well as on the experience of our research group, we conclude that, using similar matrices for the study of chronic drug exposure, children present with a higher cocaine concentration in hair and they experience more serious deleterious acute effects, probably due to a different and slower cocaine metabolism. Consequently, children must be not exposed to secondhand crack smoke under any circumstance.

  19. Chronic cat allergen exposure induces a TH2 cell-dependent IgG4 response related to low sensitization.

    Science.gov (United States)

    Renand, Amedee; Archila, Luis D; McGinty, John; Wambre, Erik; Robinson, David; Hales, Belinda J; Thomas, Wayne R; Kwok, William W

    2015-12-01

    In human subjects, allergen tolerance has been observed after high-dose allergen exposure or after completed allergen immunotherapy, which is related to the accumulation of anti-inflammatory IgG4. However, the specific T-cell response that leads to IgG4 induction during chronic allergen exposure remains poorly understood. We sought to evaluate the relationship between cat allergen-specific T-cell frequency, cat allergen-specific IgE and IgG4 titers, and clinical status in adults with cat allergy with and without cat ownership and the cellular mechanism by which IgG4 is produced. Fel d 1-, Fel d 4-, Fel d 7-, and Fel d 8-specific T-cell responses were characterized by CD154 expression after antigen stimulation. In allergic subjects without cat ownership, the frequency of cat allergen (Fel d 1 and Fel d 4)-specific TH2 (sTH2) cells correlates with higher IgE levels and is linked to asthma. Paradoxically, we observed that subjects with cat allergy and chronic cat exposure maintain a high frequency of sTH2 cells, which correlates with higher IgG4 levels and low sensitization. B cells from allergic, but not nonallergic subjects, are able to produce IgG4 after cognate interactions with sTH2 clones and Fel d 1 peptide or the Fel d 1 recombinant protein. These experiments suggest that (1) allergen-experienced B cells with the capacity to produce IgG4 are present in allergic subjects and (2) cat allergen exposure induces an IgG4 response in a TH2 cell-dependent manner. Thus IgG4 accumulation could be mediated by chronic activation of the TH2 response, which in turn drives desensitization. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. All rights reserved.

  20. Acute and chronic effects from pulse exposure of D. magna to silver and copper oxide nanoparticles

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Lützhøft, Hans-Christian Holten; Rasmussen, Rose

    2016-01-01

    Aquatic toxicity testing of nanoparticles (NPs) is challenged by their dynamic behavior in test suspensions. The resulting difficulties in controlling and characterizing exposure concentrations are detrimental to the generation of concentration-response data needed for hazard identification of NPs...... is an environmentally relevant exposure scenario for NPs, which for AgNPs and CuONPs enables more stable exposures and cause acute immobility of D. magna comparable to continuous 24 h exposures. Pulse exposure is likely relevant and applicable for other toxic and dissolving metal NPs, but this requires further research....

  1. How do macro-level contexts and policies affect the employment chances of chronically ill and disabled people? Part II: The impact of active and passive labor market policies.

    Science.gov (United States)

    Holland, Paula; Nylén, Lotta; Thielen, Karsten; van der Wel, Kjetil A; Chen, Wen-Hao; Barr, Ben; Burström, Bo; Diderichsen, Finn; Andersen, Per Kragh; Dahl, Espen; Uppal, Sharanjit; Clayton, Stephen; Whitehead, Margaret

    2011-01-01

    The authors investigate three hypotheses on the influence of labor market deregulation, decommodification, and investment in active labor market policies on the employment of chronically ill and disabled people. The study explores the interaction between employment, chronic illness, and educational level for men and women in Canada, Denmark, Norway, Sweden, and the United Kingdom, countries with advanced social welfare systems and universal health care but with varying types of active and passive labor market policies. People with chronic illness were found to fare better in employment terms in the Nordic countries than in Canada or the United Kingdom. Their employment chances also varied by educational level and country. The employment impact of having both chronic illness and low education was not just additive but synergistic. This amplification was strongest for British men and women, Norwegian men, and Danish women. Hypotheses on the disincentive effects of tighter employment regulation or more generous welfare benefits were not supported. The hypothesis that greater investments in active labor market policies may improve the employment of chronically ill people was partially supported. Attention must be paid to the differential impact of macro-level policies on the labor market participation of chronically ill and disabled people with low education, a group facing multiple barriers to gaining employment.

  2. Neurophysiological Effects of Chronic Indoor Environmental Toxic Mold Exposure on Children

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2003-01-01

    Full Text Available The phenomenon of building-related diseases is attracting much research interest in recent years because of the extent to which it affects people with compromised immune systems, especially children. In this study, we reported the neurological findings in children who attended our Center because of chronic exposure to toxic molds. Clinical neurological and neurobehavioral questionnaires were administered with the cooperation of the children�s parents. The children then underwent a series of neurophysiological tests including electroencephalogram (EEG, brainstem evoked potential (BAEP, visual evoked potential (VEP, and somatosensory evoked potential (SSEP. The results showed high levels of abnormalities in the analysis of the subjective responses derived from the questionnaires. The EEG examination was abnormal in seven out of ten of the patients compared to the controls with only one in ten with episodes of bihemispheric sharp activity. In all the patients, there was frontotemporal theta wave ativity that seemed to indicate diffuse changes characteristic of metabolic encephalopathies. Also, there was highly marked 1 to 3 Hz delta activity that was asymmetrical in the right hemisphere of the brain in three out of ten patients. The waveforms of BAEP showed abnormalities in 90% of the patients with both 15’ and 31’ check sizes compared to none in the controls. There were significant delays in waveform V in a majority of the patients representing dysfunctional cognitive process and conductive hearing loss in both ears. VEP showed clear abnormalities in four in ten of the patients with P100 amplitudes and latencies decreased bilaterally. In all the patients, there was slowing of conduction in the right tibial at an average of 36.9 ms and there was significant decrease in amplitude of response at the proximal stimulation site. Sensory latencies obtained in the median, ulnar, and sural nerves bilaterally showed abnormalities in five out of ten

  3. Exposure and genetics increase risk of beryllium sensitisation and chronic beryllium disease in the nuclear weapons industry.

    Science.gov (United States)

    Van Dyke, Michael V; Martyny, John W; Mroz, Margaret M; Silveira, Lori J; Strand, Matt; Cragle, Donna L; Tankersley, William G; Wells, Susan M; Newman, Lee S; Maier, Lisa A

    2011-11-01

    Beryllium sensitisation (BeS) and chronic beryllium disease (CBD) are caused by exposure to beryllium with susceptibility affected by at least one well-studied genetic host factor, a glutamic acid residue at position 69 (E69) of the HLA-DPβ chain (DPβE69). However, the nature of the relationship between exposure and carriage of the DPβE69 genotype has not been well studied. The goal of this study was to determine the relationship between DPβE69 and exposure in BeS and CBD. Current and former workers (n=181) from a US nuclear weapons production facility, the Y-12 National Security Complex (Oak Ridge, Tennessee, USA), were enrolled in a case-control study including 35 individuals with BeS and 19 with CBD. HLA-DPB1 genotypes were determined by PCR-SSP. Beryllium exposures were assessed through worker interviews and industrial hygiene assessment of work tasks. After removing the confounding effect of potential beryllium exposure at another facility, multivariate models showed a sixfold (OR 6.06, 95% CI 1.96 to 18.7) increased odds for BeS and CBD combined among DPβE69 carriers and a fourfold (OR 3.98, 95% CI 1.43 to 11.0) increased odds for those exposed over an assigned lifetime-weighted average exposure of 0.1 μg/m(3). Those with both risk factors had higher increased odds (OR 24.1, 95% CI 4.77 to 122). DPβE69 carriage and high exposure to beryllium appear to contribute individually to the development of BeS and CBD. Among workers at a beryllium-using facility, the magnitude of risk associated with either elevated beryllium exposure or carriage of DPβE69 alone appears to be similar.

  4. Neuropsychological effects of chronic low-dose exposure to polychlorinated biphenyls (PCBs: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Klett Martin

    2005-10-01

    Full Text Available Abstract Background Exposure to indoor air of private or public buildings contaminated with polychlorinated biphenyls (PCBs has raised health concerns in long-term users. This exploratory neuropsychological group study investigated the potential adverse effects of chronic low-dose exposure to specific air-borne low chlorinated PCBs on well-being and behavioral measures in adult humans. Methods Thirty employees exposed to indoor air contaminated with PCBs from elastic sealants in a school building were compared to 30 non-exposed controls matched for education and age, controlling for gender (age range 37–61 years. PCB exposure was verified by external exposure data and biological monitoring (PCB 28, 101, 138, 153, 180. Subjective complaints, learning and memory, executive function, and visual-spatial function was assessed by standardized neuropsychological testing. Since exposure status depended on the use of contaminated rooms, an objectively exposed subgroup (N = 16; PCB 28 = 0.20 μg/l; weighted exposure duration 17.9 ± 7 years was identified and compared with 16 paired controls. Results Blood analyses indicated a moderate exposure effect size (d relative to expected background exposure for total PCB (4.45 ± 2.44 μg/l; d = 0.4. A significant exposure effect was found for the low chlorinated PCBs 28 (0.28 ± 0.25 μg/l; d = 1.5 and 101 (0.07 ± 0.09 μg/l; d = 0.7. Although no neuropsychological effects exceeded the adjusted significance level, estimation statistics showed elevated effect sizes for several variables. The objectively exposed subgroup showed a trend towards increased subjective attentional and emotional complaints (tiredness and slowing of practical activities, emotional state as well as attenuated attentional performance (response shifting and alertness in a cued reaction task. Conclusion Chronic inhalation of low chlorinated PCBs that involved elevated blood levels was associated with a subtle attenuation of emotional well

  5. How Does Chronic Cigarette Smoke Exposure Affect Human Skin? A Global Proteomics Study in Primary Human Keratinocytes.

    Science.gov (United States)

    Rajagopalan, Pavithra; Nanjappa, Vishalakshi; Raja, Remya; Jain, Ankit P; Mangalaparthi, Kiran K; Sathe, Gajanan J; Babu, Niraj; Patel, Krishna; Cavusoglu, Nükhet; Soeur, Jeremie; Pandey, Akhilesh; Roy, Nita; Breton, Lionel; Chatterjee, Aditi; Misra, Namita; Gowda, Harsha

    2016-11-01

    Cigarette smoking has been associated with multiple negative effects on human skin. Long-term physiological effects of cigarette smoke are through chronic and not acute exposure. Molecular alterations due to chronic exposure to cigarette smoke remain unclear. Primary human skin keratinocytes chronically exposed to cigarette smoke condensate (CSC) showed a decreased wound-healing capacity with an increased expression of NRF2 and MMP9. Using quantitative proteomics, we identified 4728 proteins, of which 105 proteins were overexpressed (≥2-fold) and 41 proteins were downregulated (≤2-fold) in primary skin keratinocytes chronically exposed to CSC. We observed an alteration in the expression of several proteins involved in maintenance of epithelial barrier integrity, including keratin 80 (5.3 fold, p value 2.5 × 10 -7 ), cystatin A (3.6-fold, p value 3.2 × 10 -3 ), and periplakin (2.4-fold, p value 1.2 × 10 -8 ). Increased expression of proteins associated with skin hydration, including caspase 14 (2.2-fold, p value 4.7 × 10 -2 ) and filaggrin (3.6-fold, p value 5.4 × 10 -7 ), was also observed. In addition, we report differential expression of several proteins, including adipogenesis regulatory factor (2.5-fold, p value 1.3 × 10 -3 ) and histone H1.0 (2.5-fold, p value 6.3 × 10 -3 ) that have not been reported earlier. Bioinformatics analyses demonstrated that proteins differentially expressed in response to CSC are largely related to oxidative stress, maintenance of skin integrity, and anti-inflammatory responses. Importantly, treatment with vitamin E, a widely used antioxidant, could partially rescue adverse effects of CSC exposure in primary skin keratinocytes. The utility of antioxidant-based new dermatological formulations in delaying or preventing skin aging and oxidative damages caused by chronic cigarette smoke exposure warrants further clinical investigations and multi-omics research.

  6. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    International Nuclear Information System (INIS)

    Stueckle, Todd A.; Lu, Yongju; Davis, Mary E.; Wang, Liying; Jiang, Bing-Hua; Holaskova, Ida; Schafer, Rosana; Barnett, John B.; Rojanasakul, Yon

    2012-01-01

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As 2 O 3

  7. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Stueckle, Todd A., E-mail: tstueckle@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Lu, Yongju, E-mail: yongju6@hotmail.com [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Davis, Mary E., E-mail: mdavis@wvu.edu [Department of Physiology, West Virginia University, Morgantown, WV 26506 (United States); Wang, Liying, E-mail: lmw6@cdc.gov [Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Jiang, Bing-Hua, E-mail: bhjiang@jefferson.edu [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Holaskova, Ida, E-mail: iholaskova@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Schafer, Rosana, E-mail: rschafer@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Barnett, John B., E-mail: jbarnett@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Rojanasakul, Yon, E-mail: yrojan@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States)

    2012-06-01

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As{sub 2}O

  8. Reliability and minimal detectable change of a modified passive neck flexion test in patients with chronic nonspecific neck pain and asymptomatic subjects.

    Science.gov (United States)

    López-de-Uralde-Villanueva, Ibai; Acuyo-Osorio, Mario; Prieto-Aldana, María; La Touche, Roy

    2017-04-01

    The Passive Neck Flexion Test (PNFT) can diagnose meningitis and potential spinal disorders. Little evidence is available concerning the use of a modified version of the PNFT (mPNFT) in patients with chronic nonspecific neck pain (CNSNP). To assess the reliability of the mPNFT in subjects with and without CNSNP. The secondary objective was to assess the differences in the symptoms provoked by the mPNFT between these two populations. We used repeated measures concordance design for the main objective and cross-sectional design for the secondary objective. A total of 30 asymptomatic subjects and 34 patients with CNSNP were recruited. The following measures were recorded: the range of motion at the onset of symptoms (OS-mPNFT), the range of motion at the submaximal pain (SP-mPNFT), and evoked pain intensity on the mPNFT (VAS-mPNFT). Good to excellent reliability was observed for OS-mPNFT and SP-mPNFT in the asymptomatic group (intra-examiner reliability: 0.95-0.97; inter-examiner reliability: 0.86-0.90; intra-examiner test-retest reliability: 0.84-0.87). In the CNSNP group, a good to excellent reliability was obtained for the OS-mPNFT (intra-examiner reliability: 0.89-0.96; inter-examiner reliability: 0.83-0.86; intra-examiner test-retest reliability: 0.83-0.85) and the SP-PNFT (intra-examiner reliability: 0.94-0.98; inter-examiner reliability: 0.80-0.82; intra-examiner test-retest reliability: 0.88-0.91). The CNSNP group showed statistically significant differences in OS-mPNFT (t = 4.92; P reliable tool regardless of the examiner and the time factor. Patients with CNSNP have a decrease range of motion and more pain than asymptomatic subjects in the mPNFT. This exceeds the minimal detectable changes for OS-mPNFT and VAS-mPNFT. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The impact of exposure to radio frequency electromagnetic fields on chronic well-being in young people--a cross-sectional study based on personal dosimetry.

    Science.gov (United States)

    Heinrich, Sabine; Thomas, Silke; Heumann, Christian; von Kries, Rüdiger; Radon, Katja

    2011-01-01

    A possible influence of radio frequency electromagnetic field (RF EMF) exposure on health outcomes was investigated in various studies. The main problem of previous studies was exposure assessment. The aim of our study was the investigation of a possible association between RF EMF and chronic well-being in young persons using personal dosimetry. 3022 children and adolescents were randomly selected from the population registries of four Bavarian cities in Germany (participation 52%). Personal interview data on chronic symptoms, socio-demographic characteristics and potential confounders were collected. A 24-h radio frequency exposure profile was generated using a personal dosimeter. Exposure levels over waking hours were expressed as mean percentage of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference level. Half of the children and nearly every adolescent owned a mobile phone which was used only for short durations per day. Measured exposure was far below the current ICNIRP reference levels. The most reported chronic symptom in children and adolescents was fatigue. No statistically significant association between measured exposure and chronic symptoms was observed. Our results do not indicate an association between measured exposure to RF EMF and chronic well-being in children and adolescents. Prospective studies investigating potential long-term effects of RF EMF are necessary to confirm our results. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Prozac in the water: Chronic fluoxetine exposure and predation risk interact to shape behaviors in an estuarine crab.

    Science.gov (United States)

    Peters, Joseph R; Granek, Elise F; de Rivera, Catherine E; Rollins, Matthew

    2017-11-01

    Predators exert considerable top-down pressure on ecosystems by directly consuming prey or indirectly influencing their foraging behaviors and habitat use. Prey is, therefore, forced to balance predation risk with resource reward. A growing list of anthropogenic stressors such as rising temperatures and ocean acidification has been shown to influence prey risk behaviors and subsequently alter important ecosystem processes. Yet, limited attention has been paid to the effects of chronic pharmaceutical exposure on risk behavior or as an ecological stressor, despite widespread detection and persistence of these contaminants in aquatic environments. In the laboratory, we simulated estuarine conditions of the shore crab, Hemigrapsus oregonensis, and investigated whether chronic exposure (60 days) to field-detected concentrations (0, 3, and 30 ng/L) of the antidepressant fluoxetine affected diurnal and nocturnal risk behaviors in the presence of a predator, Cancer productus . We found that exposure to fluoxetine influenced both diurnal and nocturnal prey risk behaviors by increasing foraging and locomotor activity in the presence of predators, particularly during the day when these crabs normally stay hidden. Crabs exposed to fluoxetine were also more aggressive, with a higher frequency of agonistic interactions and increased mortality due to conflicts with conspecifics. These results suggest that exposure to field-detected concentrations of fluoxetine may alter the trade-off between resource acquisition and predation risk among crabs in estuaries. This fills an important data gap, highlighting how intra- and interspecific behaviors are altered by exposure to field concentrations of pharmaceuticals; such data more explicitly identify potential ecological impacts of emerging contaminants on aquatic ecosystems and can aid water quality management.

  11. Total arsenic concentrations in toenails quantified by two techniques provide a useful biomarker of chronic arsenic exposure in drinking water

    International Nuclear Information System (INIS)

    Adair, Blakely M.; Hudgens, Edward E.; Schmitt, Michael T.; Calderon, Rebecca L.; Thomas, David J.

    2006-01-01

    Accurate quantitation of any contaminant of interest is critical for exposure assessment and metabolism studies that support risk assessment. A preliminary step in an arsenic exposure assessment study in Nevada quantified total arsenic (TAs) concentrations in tissues as biomarkers of exposure. Participants in this study (n=95) were at least 45 years old, had lived in the area for more than 20 years, and were exposed to a wide range of arsenic concentrations in drinking water (3-2100ppb). Concentrations of TAs in blood, urine, and toenails determined by hydride generation-atomic fluorescence spectrometry (HG-AFS) ranged from below detection to 0.03, 0.76, and 12ppm, respectively; TAs in blood rarely exceeded the limit of detection. For comparison, TAs in toenails determined by neutron activation analysis (NAA) ranged from below detection to 16ppm. Significant (P 2 =0.3557 HG-AFS, adjusted r 2 =0.3922 NAA); TAs concentrations in urine were not described by drinking water As (adjusted r 2 =0.0170, P=0.1369). Analyses of TAs in toenails by HGAFS and NAA yielded highly concordant estimates (r=0.7977, P<0.0001). These results suggest that toenails are a better biomarker of chronic As exposure than urine in the current study, because the sequestration of As in toenails provides an integration of exposure over time that does not occur in urine

  12. Impact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)

    International Nuclear Information System (INIS)

    Faucher, Karine; Fichet, Denis; Miramand, Pierre; Lagardere, Jean-Paul

    2008-01-01

    The effect of chronic exposure to a low concentration (0.5 μg l -1 ) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4 h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium accumulation in gills and scales decreased significantly and fish escape behaviour had recovered. This study presents a new concept in ecotoxicology: using behavioural change to reveal the effects of pollution levels, scarcely detectable by currently used techniques (physiological responses). - Cadmium exposure involved a significant bioaccumulation in fish scales, slight damage to the lateral line system and a significant decrease in fish escape behaviour

  13. Impact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)

    Energy Technology Data Exchange (ETDEWEB)

    Faucher, Karine [Centre de Recherche sur les Ecosystemes Littoraux Anthropises, UMR 6217, CNRS-Ifremer-ULR, B.P. 5, 17137 L' Houmeau (France)], E-mail: kfaucher@ifremer.fr; Fichet, Denis; Miramand, Pierre [Centre de Recherche sur les Ecosystemes Littoraux Anthropises, UMR 6217, CNRS-Ifremer-ULR, Avenue Michel Crepeau, 17042 La Rochelle (France); Lagardere, Jean-Paul [Centre de Recherche sur les Ecosystemes Littoraux Anthropises, UMR 6217, CNRS-Ifremer-ULR, B.P. 5, 17137 L' Houmeau (France)

    2008-01-15

    The effect of chronic exposure to a low concentration (0.5 {mu}g l{sup -1}) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4 h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium accumulation in gills and scales decreased significantly and fish escape behaviour had recovered. This study presents a new concept in ecotoxicology: using behavioural change to reveal the effects of pollution levels, scarcely detectable by currently used techniques (physiological responses). - Cadmium exposure involved a significant bioaccumulation in fish scales, slight damage to the lateral line system and a significant decrease in fish escape behaviour.

  14. The effects of gestational and chronic atrazine exposure on motor behaviors and striatal dopamine in male Sprague-Dawley rats

    International Nuclear Information System (INIS)

    Walters, Jennifer L.; Lansdell, Theresa A.; Lookingland, Keith J.; Baker, Lisa E.

    2015-01-01

    This study sought to investigate the effects of environmentally relevant gestational followed by continued chronic exposure to the herbicide, atrazine, on motor function, cognition, and neurochemical indices of nigrostriatal dopamine (DA) activity in male rats. Dams were treated with 100 μg/kg atrazine, 10 mg/kg atrazine, or vehicle on gestational day 1 through postnatal day 21. Upon weaning, male offspring continued daily vehicle or atrazine gavage treatments for an additional six months. Subjects were tested in a series of behavioral assays, and 24 h after the last treatment, tissue samples from the striatum were analyzed for DA and 3,4-dihydroxyphenylacetic acid (DOPAC). At 10 mg/kg, this herbicide was found to produce modest disruptions in motor functioning, and at both dose levels it significantly lowered striatal DA and DOPAC concentrations. These results suggest that exposures to atrazine have the potential to disrupt nigrostriatal DA neurons and behaviors associated with motor functioning. - Highlights: • Male rats received gestational and chronic exposure to ATZ (10 mg/kg and 100 μg/kg). • ATZ altered locomotor activity and impaired motor coordination. • ATZ lowered striatal DA and DOPAC concentrations. • ATZ produced a potential anxiogenic effect. • ATZ did not impair performance in learning and memory assessments.

  15. Chronic exposure of adult, postnatal and in utero rat models to low-dose 137Cesium: impact on circulating biomarkers

    International Nuclear Information System (INIS)

    Manens, Line; Grison, Stéphane; Bertho, Jean-Marc; Lestaevel, Philippe; Guéguen, Yann; Benderitter, Marc; Aigueperse, Jocelyne; Souidi, Maâmar

    2016-01-01

    The presence of 137 Cesium ( 137 Cs) in the environment after nuclear accidents at Chernobyl and more recently Fukushima Daiichi raises many health issues for the surrounding populations chronically exposed through the food chain. To mimic different exposure situations, we set up a male rat model of exposure by chronic ingestion of a 137 Cs concentration likely to be ingested daily by residents of contaminated areas (6500 Bq.l −1 ) and tested contaminations lasting 9 months for adult, neonatal and fetal rats. We tested plasma and serum biochemistry to identify disturbances in general indicators (lipids, proteins, carbohydrates and electrolytes) and in biomarkers of thyroid, heart, brain, bone, kidney, liver and testis functions. Analysis of the general indicators showed increased levels of cholesterol (+26%), HDL cholesterol (+31%), phospholipids B (+15%) and phosphorus (+100%) in the postnatal group only. Thyroid, heart, brain, bone and kidney functions showed no blood changes in any model. The liver function evaluation showed changes in total bilirubin (+67%) and alkaline phosphatase (–11%) levels, but only for the rats exposed to 137 Cs intake in adulthood. Large changes in 17β-estradiol (–69%) and corticosterone (+36%) levels affected steroidogenesis, but only in the adult model. This study showed that response profiles differed according to age at exposure: lipid metabolism was most radiosensitive in the postnatal model, and steroid hormone metabolism was most radiosensitive in rats exposed in adulthood. There was no evidence of deleterious effects suggesting a potential impact on fertility or procreation.

  16. The effects of gestational and chronic atrazine exposure on motor behaviors and striatal dopamine in male Sprague-Dawley rats

    Energy Technology Data Exchange (ETDEWEB)

    Walters, Jennifer L., E-mail: Jennifer.l.walters@wmich.edu [Western Michigan University, Department of Psychology, 1903 W Michigan Ave, Kalamazoo, MI 49008-5439 (United States); Lansdell, Theresa A., E-mail: lansdel1@msu.edu [Michigan State University, Department of Pharmacology and Toxicology, 1355 Bogue Street, East Lansing, MI 48824 (United States); Lookingland, Keith J., E-mail: lookingl@msu.edu [Michigan State University, Department of Pharmacology and Toxicology, 1355 Bogue Street, East Lansing, MI 48824 (United States); Baker, Lisa E., E-mail: lisa.baker@wmich.edu [Western Michigan University, Department of Psychology, 1903 W Michigan Ave, Kalamazoo, MI 49008-5439 (United States)

    2015-12-01

    This study sought to investigate the effects of environmentally relevant gestational followed by continued chronic exposure to the herbicide, atrazine, on motor function, cognition, and neurochemical indices of nigrostriatal dopamine (DA) activity in male rats. Dams were treated with 100 μg/kg atrazine, 10 mg/kg atrazine, or vehicle on gestational day 1 through postnatal day 21. Upon weaning, male offspring continued daily vehicle or atrazine gavage treatments for an additional six months. Subjects were tested in a series of behavioral assays, and 24 h after the last treatment, tissue samples from the striatum were analyzed for DA and 3,4-dihydroxyphenylacetic acid (DOPAC). At 10 mg/kg, this herbicide was found to produce modest disruptions in motor functioning, and at both dose levels it significantly lowered striatal DA and DOPAC concentrations. These results suggest that exposures to atrazine have the potential to disrupt nigrostriatal DA neurons and behaviors associated with motor functioning. - Highlights: • Male rats received gestational and chronic exposure to ATZ (10 mg/kg and 100 μg/kg). • ATZ altered locomotor activity and impaired motor coordination. • ATZ lowered striatal DA and DOPAC concentrations. • ATZ produced a potential anxiogenic effect. • ATZ did not impair performance in learning and memory assessments.

  17. Chronic copper exposure and fatty acid composition of the amphipod Dikerogammarus villosus: Results from a field study

    Energy Technology Data Exchange (ETDEWEB)

    Maazouzi, Chafik [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: maazouzi@univ-metz.fr; Masson, Gerard [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: masson1@univ-metz.fr; Izquierdo, Maria Soledad [Grupo de Investigacion en Acuicultura, ULPGC and ICCM, P.O. Box 56, 35200 Telde, Las Palmas de Gran Canaria (Spain)], E-mail: mizquierdo@dbio.ulpgc.es; Pihan, Jean-Claude [Universite de Metz, Laboratoire Interactions Ecotoxicologie Biodiversite Ecosystemes (LIEBE), CNRS UMR 7146, Avenue General Delestraint, 57070 Metz (France)], E-mail: pihan@univ-metz.fr

    2008-11-15

    Field study allows assessment of long-term effects on fatty acid (FA) composition of organisms under chronic exposure to metals. One expected effect of copper is peroxidation of lipids and essentially polyunsaturated fatty acids (PUFA). FA analysis was established for the amphipod Dikerogammarus villosus subjected to different degrees of copper exposure (4-40 {mu}g Cu L{sup -1}). A previous study in our team showed that this species regulates its body Cu concentration (106-135 mg Cu kg{sup -1} dry weight). Despite the high capacity of bioaccumulation, the absence of a correlation between copper concentration in D. villosus and water prevents its use as bioindicator of copper pollution. Both sexes from the most polluted site showed the lowest total FA content, but the highest PUFA percent, mainly of the long-chained variety (C20-C22). Mechanisms leading to the prevention of lipid peroxidation in this species were discussed (metallothioneins and intracellular granules) and proposed with support from literature data. - Under chronic copper exposure, Dikerogammarus villosus loses in total fatty acids content but increases its essential {omega}3 and {omega}6 PUFA percent.

  18. Chronic stress exposure may affect the brain's response to high calorie food cues and predispose to obesogenic eating habits.

    Science.gov (United States)

    Tryon, Matthew S; Carter, Cameron S; Decant, Rashel; Laugero, Kevin D

    2013-08-15

    Exaggerated reactivity to food cues involving calorically-dense foods may significantly contribute to food consumption beyond caloric need. Chronic stress, which can induce palatable "comfort" food consumption, may trigger or reinforce neural pathways leading to stronger reactions to highly rewarding foods. We implemented functional magnetic resonance imaging (fMRI) to assess whether chronic stress influences activation in reward, motivation and executive brain regions in response to pictures of high calorie and low calorie foods in thirty women. On separate lab visits, we also assessed food intake from a snack food buffet and circulating cortisol. In women reporting higher chronic stress (HCS), pictures of high calorie foods elicited exaggerated activity in regions of the brain involving reward, motivation, and habitual decision-making. In response to pictures of high calorie food, higher chronic stress was also associated with significant deactivation in frontal regions (BA10; BA46) linked to strategic planning and emotional control. In functional connectivity analysis, HCS strengthened connectivity between amygdala and the putamen, while LCS enhanced connectivity between amygdala and the anterior cingulate and anterior prefrontal cortex (BA10). A hypocortisolemic signature and more consumption of high calorie foods from the snack buffet were observed in the HCS group. These results suggest that persistent stress exposure may alter the brain's response to food in ways that predispose individuals to poor eating habits which, if sustained, may increase risk for obesity. © 2013.

  19. Neuropeptide Y stimulation as primary target for preventive measures of maladaptative cardiovascular reactions in occupational chronic stress exposure.

    Science.gov (United States)

    Ciumaşu-Rîmbu, Mălina; Popa, Livia; Vulpoi, Carmen

    2012-01-01

    Chronic stress may produce a decrease in central NPY expression and subjects exposed to it may prove hypersensitivity to a novel stressor with dysfunctions in the NPY system and cardiovascular maladaptation to stress, even hypertension. Upregulation of NPY expression may contribute to successful behavioral adaptation to stress by reducing cardiovascular tone and suppressing anxious behaviors. Adaptogens, a new class of metabolic regulators stimulate NPY expression and release. The aim of this study is to increase tolerance and adaptation to stress of hypersensitive to novel stressor, occupational chronic stress exposed subjects with cardiovascular maladaptation to mild new stressor using adaptogens as part of prevention protocol. 40 military personnel with known cardiostressor reactional mode and occupational chronic stress exposure were exposed to mild novel stressor: occupational medicine routine evaluation and clinically assessed for maladaptative cardiovascular response prior and before application of 30 day prevention protocol. Employees were randomly split in two groups, one receiving standard prevention protocol (lifestyle counseling) plus adaptogens in multiple dose administration, twice daily and the other receiving only standard prevention protocol. We found significant statistic differences in all cardiovascular parameters in adaptogen group and only in diastolic blood pressure in control group. Adaptogens could be an important factor in successful prevention protocols of chronic occupational stress dysfunctions involving NPY systems.

  20. Chronic corticosterone exposure persistently elevates the expression of memory-related genes in the lateral amygdala and enhances the consolidation of a Pavlovian fear memory.

    Directory of Open Access Journals (Sweden)

    Melissa S Monsey

    Full Text Available Chronic exposure to stress has been widely implicated in the development of anxiety disorders, yet relatively little is known about the long-term effects of chronic stress on amygdala-dependent memory formation. Here, we examined the effects of a history of chronic exposure to the stress-associated adrenal steroid corticosterone (CORT on the consolidation of a fear memory and the expression of memory-related immediate early genes (IEGs in the lateral nucleus of the amygdala (LA. Rats received chronic exposure to CORT (50 μg/ml in their drinking water for 2 weeks and were then titrated off the CORT for an additional 6 days followed by a 2 week 'wash-out' period consisting of access to plain water. Rats were then either sacrificed to examine the expression of memory-related IEG expression in the LA or given auditory Pavlovian fear conditioning. We show that chronic exposure to CORT leads to a persistent elevation in the expression of the IEGs Arc/Arg3.1 and Egr-1 in the LA. Further, we show that rats with a history of chronic CORT exposure exhibit enhanced consolidation of a fear memory; short-term memory (STM is not affected, while long-term memory (LTM is significantly enhanced. Treatment with the selective serotonin reuptake inhibitor (SSRI fluoxetine following the chronic CORT exposure period was observed to effectively reverse both the persistent CORT-related increases in memory-related IEG expression in the LA and the CORT-related enhancement in fear memory consolidation. Our findings suggest that chronic exposure to CORT can regulate memory-related IEG expression and fear memory consolidation processes in the LA in a long-lasting manner and that treatment with fluoxetine can reverse these effects.

  1. Chronic corticosterone exposure persistently elevates the expression of memory-related genes in the lateral amygdala and enhances the consolidation of a Pavlovian fear memory.

    Science.gov (United States)

    Monsey, Melissa S; Boyle, Lara M; Zhang, Melinda L; Nguyen, Caroline P; Kronman, Hope G; Ota, Kristie T; Duman, Ronald S; Taylor, Jane R; Schafe, Glenn E

    2014-01-01

    Chronic exposure to stress has been widely implicated in the development of anxiety disorders, yet relatively little is known about the long-term effects of chronic stress on amygdala-dependent memory formation. Here, we examined the effects of a history of chronic exposure to the stress-associated adrenal steroid corticosterone (CORT) on the consolidation of a fear memory and the expression of memory-related immediate early genes (IEGs) in the lateral nucleus of the amygdala (LA). Rats received chronic exposure to CORT (50 μg/ml) in their drinking water for 2 weeks and were then titrated off the CORT for an additional 6 days followed by a 2 week 'wash-out' period consisting of access to plain water. Rats were then either sacrificed to examine the expression of memory-related IEG expression in the LA or given auditory Pavlovian fear conditioning. We show that chronic exposure to CORT leads to a persistent elevation in the expression of the IEGs Arc/Arg3.1 and Egr-1 in the LA. Further, we show that rats with a history of chronic CORT exposure exhibit enhanced consolidation of a fear memory; short-term memory (STM) is not affected, while long-term memory (LTM) is significantly enhanced. Treatment with the selective serotonin reuptake inhibitor (SSRI) fluoxetine following the chronic CORT exposure period was observed to effectively reverse both the persistent CORT-related increases in memory-related IEG expression in the LA and the CORT-related enhancement in fear memory consolidation. Our findings suggest that chronic exposure to CORT can regulate memory-related IEG expression and fear memory consolidation processes in the LA in a long-lasting manner and that treatment with fluoxetine can reverse these effects.

  2. Persistent modification of Na{sub v}1.9 following chronic exposure to insecticides and pyridostigmine bromide

    Energy Technology Data Exchange (ETDEWEB)

    Nutter, Thomas J., E-mail: tnutter@dental.ufl.edu; Cooper, Brian Y., E-mail: bcooper@dental.ufl.edu

    2014-06-15

    Many veterans of the 1991 Gulf War (GW) returned from that conflict with a widespread chronic pain affecting deep tissues. Recently, we have shown that a 60 day exposure to the insecticides permethrin, chlorpyrifos, and pyridostigmine bromide (NTPB) had little influence on nociceptor action potential forming Na{sub v}1.8, but increased K{sub v}7 mediated inhibitory currents 8 weeks after treatment. Using the same exposure regimen, we used whole cell patch methods to examine whether the influences of NTPB could be observed on Na{sub v}1.9 expressed in muscle and vascular nociceptors. During a 60 day exposure to NTPB, rats exhibited lowered muscle pain thresholds and increased rest periods, but these measures subsequently returned to normal levels. Eight and 12 weeks after treatments ceased, DRG neurons were excised from the sensory ganglia. Whole cell patch studies revealed little change in voltage dependent activation and deactivation of Na{sub v}1.9, but significant increases in the amplitude of Na{sub v}1.9 were observed 8 weeks after exposure. Cellular studies, at the 8 week delay, revealed that NTPB also significantly prolonged action potential duration and afterhyperpolarization (22 °C). Acute application of permethrin (10 μM) also increased the amplitude of Na{sub v}1.9 in skin, muscle and vascular nociceptors. In conclusion, chronic exposure to Gulf War agents produced long term changes in the amplitude of Na{sub v}1.9 expressed in muscle and vascular nociceptors. The reported increases in K{sub v}7 amplitude may have been an adaptive response to increased Na{sub v}1.9, and effectively suppressed behavioral pain measures in the post treatment period. Factors that alter the balance between Na{sub v}1.9 and K{sub v}7 could release spontaneous discharge and produce chronic deep tissue pain. - Highlights: • Rats were treated 60 days with permethrin, chlorpyrifos and pyridostigmine bromide. • 8 weeks after treatments, Nav1.9 activation and deactivation were

  3. MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

    Energy Technology Data Exchange (ETDEWEB)

    Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Aguado, Andrea [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Zhenyukh, Olha; Briones, Ana María [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Alonso, María Jesús [Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón (Spain); Vassallo, Dalton Valentim [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Health Science Center of Vitória-EMESCAM, Vitória, ES CEP 29045-402 (Brazil); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain)

    2015-03-01

    Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

  4. Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats

    Data.gov (United States)

    U.S. Environmental Protection Agency — Pulmonary effects to ozone with rats that have chronically exercised or have been continuously sedentary. Also includes body composition of both groups throughout...

  5. Effects on body size and composition of chronic exposure to altered gravity. [centrifuging stress in mammals

    Science.gov (United States)

    Pitts, G. C.

    1977-01-01

    The effects of chronic centrifugation on body composition and growth of rats, mice, monkeys, and man are studied. The benefits of exercise and restraint during acceleration are investigated. Physiological regulation and energy balance are also discussed.

  6. Chronic exposure of ecosystems and public to elements in trace contributions

    International Nuclear Information System (INIS)

    2004-01-01

    The needs in radiation protection come towards the question of chronic contaminations by trace elements or radioactive compounds. The chronicity induces to take into account a whole of redistribution mechanisms more important than the only ways of the most direct transfer. In the case of environment, that is going to become one of the way of public contamination is a target to protect, the important work is to link the contamination situation to eventual consequences on the ecosystems situation. (N.C.)

  7. Exposure to nitrogen dioxide and chronic obstructive pulmonary disease (COPD) in adults: a systematic review and meta-analysis.

    Science.gov (United States)

    Zhang, Zili; Wang, Jian; Lu, Wenju

    2018-05-01

    Exposure to nitrogen dioxide (NO 2 ) has long been linked to elevated mortality and morbidity from epidemiological evidences. However, questions remain unclear whether NO 2 acts directly on human health or being an indicator of other ambient pollutants. In this study, random-effect meta-analyses were performed on examining exposure to nitrogen oxide (NO x ) and its association with chronic obstructive pulmonary disease (COPD). The overall relative risk (RR) of COPD risk related to a 10 μg/m 3 increase in NO 2 exposure increased by 2.0%. The pooled effect on prevalence was 17% with an increase of 10 μg/m 3 in NO 2 concentration, and 1.3% on hospital admissions, and 2.6% on mortality. The RR of COPD cases related to NO 2 long-term exposure was 2.5 and 1.4% in short-term exposure. The COPD effect related with a 10 μg/m 3 increase in exposure to a general outdoor-sourced NO 2 was 1.7 and 17.8% to exposure to an exclusively traffic-sourced NO 2 ; importantly, we did observe the effect of NO 2 on COPD mortality with a large majority in lag0. Long-term traffic exerted more severe impairments on COPD prevalence than long-term or short-term outdoor effect; long-term mortality effect on COPD was serious in single model from this meta-analysis. Overall, our study reported consistent evidence of the potential positive association between NO 2 and COPD risk.

  8. Alterations in prostacyclin and thromboxane formation by chronic cigarette smoke exposure: temporal relationships and whole smoke vs. gas phase

    Energy Technology Data Exchange (ETDEWEB)

    Lubawy, W.C.; Culpepper, B.T.; Valentovic, M.A.

    1986-04-01

    Chronic cigarette smoke exposure in vivo causes decreased conversion of (/sup 14/C)arachidonic acid (AA) to prostacyclin (PGI2) by isolated aortic tissue and increased conversion to thromboxane (TXA2) by isolated platelets from rats. Alterations in the PGI2/TXA2 balance may be part of the mechanism through which smoking increases the risk of cardiovascular disease. To study the influence of smoke exposure duration on this response, male rats were exposed daily to 10 puffs of freshly generated cigarette smoke. Animals were killed after 1, 4, 14, 28 and 57 days of smoke exposure and 3, 7, 14 and 28 days after cessation of the 57-day of smoke-exposure regimen. Elevated carboxyhemoglobin levels during the smoke-exposure sessions verified smoke (gas phase) inhalation. Statistically significant alterations in prostacyclin synthesis preceded those of thromboxane. A decrease of 20-25% (P less than 0.05) in PGI2 production from (/sup 14/C)AA in isolated aortic tissue was found beginning 28 days after smoke was initiated and quickly rebounded when smoke exposure was terminated. Increased production of TXA2 from (/sup 14/C)AA by isolated platelets became statistically significant (P less than 0.05) on the 57th day and returned to normal 7-14 days after cessation of smoke exposure. To determine the effect of gas phase constituents on the PGI2/TXA2 balance a second series of experiments divided male and female Sprague-Dawley rats into sham, whole smoke and gas phase groups. Gas phase was produced by passing whole smoke through a Cambridge filter to remove particulate matter. Per cent COHb averaged 1.4 for sham, 7.8 for whole smoke and 9.4 for gas phase groups.

  9. Impact of Particulate Matter Exposure and Surrounding "Greenness" on Chronic Absenteeism in Massachusetts Public Schools.

    Science.gov (United States)

    MacNaughton, Piers; Eitland, Erika; Kloog, Itai; Schwartz, Joel; Allen, Joseph

    2017-02-20

    Chronic absenteeism is associated with poorer academic performance and higher attrition in kindergarten to 12th grade (K-12) schools. In prior research, students who were chronically absent generally had fewer employment opportunities and worse health after graduation. We examined the impact that environmental factors surrounding schools have on chronic absenteeism. We estimated the greenness (Normalized Difference Vegetation Index (NDVI)) and fine particulate matter air pollution (PM 2.5 ) within 250 m and 1000 m respectively of each public school in Massachusetts during the 2012-2013 academic year using satellite-based data. We modeled chronic absenteeism rates in the same year as a function of PM 2.5 and NDVI, controlling for race and household income. Among the 1772 public schools in Massachusetts, a 0.15 increase in NDVI during the academic year was associated with a 2.6% ( p value absenteeism rates, and a 1 μg/m³ increase in PM 2.5 during the academic year was associated with a 1.58% ( p value absenteeism rates. Based on these percentage changes in chronic absenteeism, a 0.15 increase in NDVI and 1 μg/m³ increase in PM 2.5 correspond to 25,837 fewer students and 15,852 more students chronically absent each year in Massachusetts respectively. These environmental impacts on absenteeism reinforce the need to protect green spaces and reduce air pollution around schools.

  10. Induction of chronic kidney failure in a long-term peritoneal exposure model in the rat: effects on functional and structural peritoneal alterations

    NARCIS (Netherlands)

    Vrtovsnik, François; Coester, Annemieke M.; Lopes-Barreto, Deirisa; de Waart, Dirk R.; van der Wal, Allard C.; Struijk, Dirk G.; Krediet, Raymond T.; Zweers, Machteld M.

    2010-01-01

    A long-term peritoneal exposure model has been developed in Wistar rats. Chronic daily exposure to 3.86% glucose based, lactate buffered, conventional dialysis solutions is possible for up to 20 weeks and induces morphological abnormalities similar to those in long-term peritoneal dialysis (PD)

  11. MRI characterization of structural mouse brain changes in response to chronic exposure to the glufosinate ammonium herbicide.

    Science.gov (United States)

    Meme, Sandra; Calas, André-Guilhem; Montécot, Céline; Richard, Oliver; Gautier, Hélène; Gefflaut, Thierry; Doan, Bich Thuy; Même, William; Pichon, Jacques; Beloeil, Jean-Claude

    2009-10-01

    Glufosinate ammonium (GLA) is the active component of herbicides widely used in agriculture, truck farming, or public domains. GLA acts by inhibiting the plant glutamine synthetase (GlnS). It also inhibits mammalian GlnS in vitro and ex vivo. In the central nervous system this enzyme is exclusively localized in glial cells. Whereas acute neurotoxic effects of GLA are well documented, long-term effects during chronic exposure at low doses remain largely undisclosed. In the present work, C57BL/6J mice were treated intraperitoneally with 2.5, 5, and 10 mg/kg of GLA three times a week during 10 weeks. Cerebral magnetic resonance imaging (MRI) experiments were performed at high field (9.4 T) and the images were analyzed with four texture analysis (TA) methods. TA highlighted structural changes in seven brain structures after chronic GLA treatments. Changes are dose dependent and can be seen at a dose as low as 2.5 mg/kg for two areas, namely hippocampus and somatosensorial cortex. Glial fibrillary acidic protein (GFAP) expression in the same seven brain structures and GlnS activity in the hippocampus and cortex areas were also studied. The number of GFAP-positive cells is modified in six out of the seven areas examined. GlnS activity was significantly increased in the hippocampus but not in the cortex. These results indicate some kind of suffering at the cerebral level after chronic GLA treatment. Changes in TA were compared with the modification of the number of GFAP-positive astrocytes in the studied brain areas after GLA treatment. We show that the noninvasive MRI-TA is a sensitive method and we suggest that it would be a very helpful tool that can efficiently contribute to the detection of cerebral alterations in vivo during chronic exposure to xenobiotics.

  12. Concomitant stress potentiates the preference for, and consumption of, ethanol induced by chronic pre-exposure to ethanol

    Directory of Open Access Journals (Sweden)

    G. Morais-Silva

    2016-01-01

    Full Text Available Ethanol abuse is linked to several acute and chronic injuries that can lead to health problems. Ethanol addiction is one of the most severe diseases linked to the abuse of this drug. Symptoms of ethanol addiction include compulsive substance intake and withdrawal syndrome. Stress exposure has an important role in addictive behavior for many drugs of abuse (including ethanol, but the consequences of stress and ethanol in the organism when these factors are concomitant results in a complex interaction. We investigated the effects of concomitant, chronic administration of ethanol and stress exposure on the withdrawal and consumption of, as well as the preference for, ethanol in mice. Male Swiss mice (30–35 g, 8-10 per group were exposed to an ethanol liquid diet as the only source of food for 15 days. In the final 5 days, they were exposed to forced swimming stress. Twelve hours after removal of the ethanol liquid diet, animals were evaluated for ethanol withdrawal by measuring anxiety-related behaviors and locomotor activity. Twenty-four hours after evaluation of ethanol withdrawal, they were evaluated for voluntary consumption of ethanol in a “three-bottle choice” paradigm. Mice exposed to chronic consumption of ethanol had decreased locomotor activity during withdrawal. Contrary to our expectations, a concomitant forced swimming stress did not aggravate ethanol withdrawal. Nevertheless, simultaneous ethanol administration and stress exposure increased voluntary consumption of ethanol, mainly solutions containing high concentrations of ethanol. These results showed that stressful situations during ethanol intake may aggravate specific addiction-related behaviors.

  13. The effect of chronic ozone exposure on the activation of endoplasmic reticulum stress and apoptosis in rat hippocampus

    Directory of Open Access Journals (Sweden)

    Erika Rodríguez-Martínez

    2016-10-01

    Full Text Available The chronic exposure to low doses of ozone, like in environmental pollution, leads to a state of oxidative stress, which has been proposed to contribute to neurodegenerative disorders, including Alzheimer's disease. It induces an increase of calcium in the endoplasmic reticulum (ER, which produces ER stress. On the other hand, different studies show that, in diseases such as Alzheimer’s, there exist disturbances in protein folding where ER plays an important role. The objective of this study was to evaluate the state of chronic oxidative stress on ER stress and its relationship with apoptotic death in the hippocampus of rats exposed to low doses of ozone. We used 108 male Wistar rats randomly divided into five groups. The groups received one of the following treatments: 1 Control (air, 2 Ozone (O3 7 days, 3 O3 15 days, 4 O3 30 days, 5 O3 60 days, and 6 O3 90 days. Two hours after each treatment, the animals were sacrificed and the hippocampus was extracted. Afterwards, the tissue was processed for western blot and immunohistochemistry using the following antibodies: ATF6, GRP8 and caspase 12. It was also performed TUNEL assay and electronic microscopy. Our results show an increase in ATF6, GRP78 and caspase 12 as well as ER ultrastructural alterations and an increase of TUNEL positive cells after 60 and 90 days of exposure to ozone. With the obtained results, we can conclude that oxidative stress induced by chronic exposure to low doses of ozone leads to ER stress. ER stress activates ATF6 inducing the increase of GRP78 in the cytoplasm, which leads to the increase in the nuclear translocation of ATF6. Finally, the translocation creates a vicious cycle that, together with the activation of the cascade for apoptotic cell death, contributes to the maintenance of ER stress. These events potentially contribute in the neurodegeneration processes in diseases like Alzheimer’s Disease.

  14. Concomitant stress potentiates the preference for, and consumption of, ethanol induced by chronic pre-exposure to ethanol.

    Science.gov (United States)

    Morais-Silva, G; Fernandes-Santos, J; Moreira-Silva, D; Marin, M T

    2016-01-01

    Ethanol abuse is linked to several acute and chronic injuries that can lead to health problems. Ethanol addiction is one of the most severe diseases linked to the abuse of this drug. Symptoms of ethanol addiction include compulsive substance intake and withdrawal syndrome. Stress exposure has an important role in addictive behavior for many drugs of abuse (including ethanol), but the consequences of stress and ethanol in the organism when these factors are concomitant results in a complex interaction. We investigated the effects of concomitant, chronic administration of ethanol and stress exposure on the withdrawal and consumption of, as well as the preference for, ethanol in mice. Male Swiss mice (30-35 g, 8-10 per group) were exposed to an ethanol liquid diet as the only source of food for 15 days. In the final 5 days, they were exposed to forced swimming stress. Twelve hours after removal of the ethanol liquid diet, animals were evaluated for ethanol withdrawal by measuring anxiety-related behaviors and locomotor activity. Twenty-four hours after evaluation of ethanol withdrawal, they were evaluated for voluntary consumption of ethanol in a "three-bottle choice" paradigm. Mice exposed to chronic consumption of ethanol had decreased locomotor activity during withdrawal. Contrary to our expectations, a concomitant forced swimming stress did not aggravate ethanol withdrawal. Nevertheless, simultaneous ethanol administration and stress exposure increased voluntary consumption of ethanol, mainly solutions containing high concentrations of ethanol. These results showed that stressful situations during ethanol intake may aggravate specific addiction-related behaviors.

  15. Chronic alcohol exposure disrupts CB1 regulation of GABAergic transmission in the rat basolateral amygdala

    DEFF Research Database (Denmark)

    Varodayan, Florence P.; Bajo, Michal; Soni, Neeraj

    2017-01-01

    in BLA pyramidal neurons of rats exposed to 2–3 weeks intermittent ethanol. In the naïve rat BLA, the CB1 agonist WIN 55,212-2 (WIN) decreased GABA release, and this effect was prevented by the CB1 antagonist AM251. AM251 alone increased GABA release via a mechanism requiring postsynaptic calcium-dependent......1 influence on BLA GABAergic transmission that is dysregulated by chronic ethanol exposure and, thus, may contribute to the alcohol-dependent state....

  16. Effects of acute and chronic exposure to lead on the behavior of the pond snail Helisoma trivolvis

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, V.T.; Copeland, J. [Georgia Southern Univ., Statesboro, GA (United States)

    1997-09-01

    The behavior of aquatic invertebrates may be useful as an indicator for the presence of toxicants in both freshwater and marine environments. The pond snail Helisoma trivolvis, the red ram`s horn, was exposed to low levels of lead (0.05 ppm). Chronic exposure significantly reduced the number of head movements but had no affect on radula movement or antenna twitches. Acute exposure resulted in curling of the foot that lasted 0.5 to 14.0 minutes. Electrochemical analysis of lead levels within treated snails indicated a higher concentration of lead in the tissue than that in the treated environment. Organ analysis of the digestive gland, 1 salivary gland, reproductive organs and the cerebral ganglion is currently being studied.

  17. Effects of chronic produced water exposure on the expression of some immune-related genes of juvenile Atlantic cod

    International Nuclear Information System (INIS)

    Perez Casanova, J.; Hamoutene, D.; Samuelson, S.; Burt, K.; King, T.; Lee, K.

    2010-01-01

    This study assessed the impacts of exposure to processed water produced by offshore oil operators on immune-related genes of juvenile Atlantic cod exposed to processed water for a period of 22 weeks. The study investigated the influence of processed water concentrations on growth parameters; food consumption; plasma cortisol; respiratory burst activity (RB); and mRNA expression. The study showed that the RB of circulating leukocytes was significantly elevated. Significant up-regulation of the mRNA expression of microglobulin, immunoglobulin light chain, and interleukins was observed in some fish. The down-regulation of the interferon stimulated gene was also observed. The study indicated that chronic exposure to significant amounts of processed water causes modulations of the immune system of juvenile Atlantic cod.

  18. Impact of water-accommodated fractions of crude oil on Atlantic cod, Gadus morhua following chronic exposure

    International Nuclear Information System (INIS)

    Khan, R.

    2010-01-01

    This study examined the long-term effects of hydrocarbon exposure on the gonadal development of fish. Mature Atlantic cod (Gadus morhua) were exposed to low concentrations of water accommodated fractions (WAFs) of polycyclic aromatic hydrocarbons (PAHs) in an ambient flowthrough seawater system. Some PAH-exposed cod groups were depurated afterwards for 38 to 287 days. Mortality was rare, and external lesions occurred only in the PAH-exposed groups. The gonado-somatic index revealed that gonadal development was disrupted in both sexes and spawning and spermiation was delayed in the 33 depurated PAH-groups. The findings indicate that chronic exposure to WAFs in the water column may have an adverse effect on reproduction in Atlantic cod.

  19. Effects of chronic produced water exposure on the expression of some immune-related genes of juvenile Atlantic cod

    Energy Technology Data Exchange (ETDEWEB)

    Perez Casanova, J.; Hamoutene, D.; Samuelson, S.; Burt, K.; King, T. [Fisheries and Oceans Canada, St. John' s, NL (Canada); Lee, K. [Fisheries and Oceans Canada, Dartmouth, NS (Canada)

    2010-07-01

    This study assessed the impacts of exposure to processed water produced by offshore oil operators on immune-related genes of juvenile Atlantic cod exposed to processed water for a period of 22 weeks. The study investigated the influence of processed water concentrations on growth parameters; food consumption; plasma cortisol; respiratory burst activity (RB); and mRNA expression. The study showed that the RB of circulating leukocytes was significantly elevated. Significant up-regulation of the mRNA expression of microglobulin, immunoglobulin light chain, and interleukins was observed in some fish. The down-regulation of the interferon stimulated gene was also observed. The study indicated that chronic exposure to significant amounts of processed water causes modulations of the immune system of juvenile Atlantic cod.

  20. The risk of chronic traumatic brain injury in professional boxing: change in exposure variables over the past century.

    Science.gov (United States)

    Clausen, H; McCrory, P; Anderson, V

    2005-09-01

    To determine if boxing exposure has changed over time and hence if current professional boxers are at the same risk of developing chronic traumatic brain injury (CTBI) as historical controls. Literature review of published studies and analysis of data of active professional boxers. Professional boxers in the United Kingdom and Australia. Boxing history and participation in sparring and professional bouts. Since the 1930s, the average duration of a professional boxer's career has dropped from 19 years to five years, and the mean number of career bouts has reduced from 336 to 13. This is despite no significant decline in participation rates from 1931 until 2002. The incidence of boxing related CTBI will diminish in the current era of professional boxing because of the reduction in exposure to repetitive head trauma and increasing medical monitoring of boxers, with preparticipation medical and neuroimaging assessments resulting in the detection of early and potentially pre-symptomatic cases of CTBI.

  1. Studies of adaptive response and mutation induction in MCF-10A cells following exposure to chronic or acute ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Manesh, Sara Shakeri; Sangsuwan, Traimate; Wojcik, Andrzej; Haghdoost, Siamak, E-mail: Siamak.haghdoost@su.se

    2015-10-15

    Highlights: • 50 mGy at 1.4 mGy/h induces adaptive response in MCF-10A at mutation level. • Low dose rate γ-radiation does not induce adaptive response at survival level. • Overall, a dose rate effect is absent at the level of mutation in MCF-10A cells. - Abstract: A phenomenon in which exposure to a low adapting dose of radiation makes cells more resistant to the effects of a subsequent high dose exposure is termed radio-adaptive response. Adaptive response could hypothetically reduce the risk of late adverse effects of chronic or acute radiation exposures in humans. Understanding the underlying mechanisms of such responses is of relevance for radiation protection as well as for the clinical applications of radiation in medicine. However, due to the variability of responses depending on the model system and radiation condition, there is a need to further study under what conditions adaptive response can be induced. In this study, we analyzed if there is a dose rate dependence for the adapting dose, assuming that the adapting dose induces DNA response/repair pathways that are dose rate dependent. MCF-10A cells were exposed to a 50 mGy adapting dose administered acutely (0.40 Gy/min) or chronically (1.4 mGy/h or 4.1 mGy/h) and then irradiated by high acute challenging doses. The endpoints of study include clonogenic cell survival and mutation frequency at X-linked hprt locus. In another series of experiment, cells were exposed to 100 mGy and 1 Gy at different dose rates (acutely and chronically) and then the mutation frequencies were studied. Adaptive response was absent at the level of clonogenic survival. The mutation frequencies were significantly decreased in the cells pre-exposed to 50 mGy at 1.4 mGy/h followed by 1 Gy acute exposure as challenging dose. Importantly, at single dose exposures (1 Gy or 100 mGy), no differences at the level of mutation were found comparing different dose rates.

  2. Effects of in vivo chronic exposure to pendimethalin on EROD activity and antioxidant defenses in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Danion, Morgane; Le Floch, Stéphane; Lamour, François; Quentel, Claire

    2014-01-01

    Pendimethalin, an herbicide active substance frequently used in terrestrial systems, has detected in European aquatic ecosystems. Reliable indicators still need to be found in order to properly assess the impact of pesticides in fish. After an in vivo chronic exposure to pendimethalin, the detoxification process and the antioxidant defense system were assessed in 120 adult rainbow trout, Oncorhynchus mykiss. Four nominal exposure conditions were tested: control (C), 500 ng L(-1) (P500), 800 ng L(-1) (P800) and the commercial formulation Prowl(®) at 500 ng L(-1) (Pw500). Fish samples were made after a 28 day exposure period (D28) and after a fifteen day recovery period in clean fresh water (D43). At D28, ethoxyresorufin-O-deethylase (EROD) activity was not activated in liver in spite of the pendimethalin uptake in fish. At D43, EROD activity in fish exposed to the commercial product was lower than in control fish, which may be explained by the high presence of herbicide in fish (613±163 ng g bile(-1)). Furthermore, antioxidant defense responses were set up by trout in gills and liver following chronic exposure to 800 ng L(-1) of pendimethalin concentration. While the glutathione content (GSH) decreased in gills, it increased in liver associated with higher activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD). These disturbances could lead to reactive oxygen species production and oxidative stress in the vital organs in fish. After fifteen days in clean water, while the SOD activity was restored, the GSH content and GPx activity were still significantly disturbed in fish exposed to pendimethalin in comparison with control. These significant differences between treatments in antioxidant defenses parameters measured, attesting to the irreversibility of the effects. © 2013 Published by Elsevier Inc.

  3. Evaluation of the effects of chronic biomass fuel smoke exposure on peripheral endothelial functions: an observational study.

    Science.gov (United States)

    Buturak, Ali; Genç, Ahmet; Ulus, Ozden Sıla; Duygu, Egemen; Okmen, Arda Sanlı; Uyarel, Hüseyin

    2011-09-01

    To evaluate the effect of chronic biomass fuel (BMF) smoke exposure on peripheral endothelial functions. Forty-seven healthy subjects who have been exposed to BMF smoke since birth (mean age 31.6±6.8 years, 21 male) were enrolled in the present cross-sectional observational study. The control group consisted of 32 healthy subjects (mean age 27.9±4.4 years, 11 male). The carotid intima media thickness (CIMT), flow associated dilatation (FAD %) and endothelium independent vasodilatation (GTN %) were assessed in all subjects. The carotid CIMT was defined as the distance between the leading edge of the lumen-intima and the media-adventitia interfaces. FAD % was defined as the percentage change in the internal diameter of the brachial artery during reactive hyperemia related to the baseline. GTN % was defined as the change in diameter in response to the application of 400 µg of glyceril trinitrate relative to the baseline scan at the end of the fourth minute. Statistical analysis was performed using Student's t-test, Chi-square test and Spearman rank order correlation analysis. The average exposure time of the subjects to biomass fuel smoke was 31.7±6.6 years. They have been exposed to dung inhalation products meanly 8.3±1.8 months in a year seasonally. The average daily exposure time was 15.7±3.3 hours. CIMT values of the two groups were not statistically different from each other (0.47±0.09 vs. 0.49±0.06 mm, p=0.138). However, a markedly reduced FAD % was determined in the study group (5.06±4.95 vs. 10.7±4.64, pinhalation products. Therefore, chronic BMF smoke exposure may be a risk factor for the development of endothelial dysfunction.

  4. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Directory of Open Access Journals (Sweden)

    Dhananjay R Namjoshi

    Full Text Available Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE, a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS. How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI.

  5. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Science.gov (United States)

    Namjoshi, Dhananjay R; Cheng, Wai Hang; Carr, Michael; Martens, Kris M; Zareyan, Shahab; Wilkinson, Anna; McInnes, Kurt A; Cripton, Peter A; Wellington, Cheryl L

    2016-01-01

    Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE), a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS). How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI) induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration) platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone) from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI) behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI.

  6. Using a Ventilation Controller to Optimize Residential Passive Ventilation For Energy and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-01

    One way to reduce the energy impact of providing residential ventilation is to use passive and hybrid systems. However, these passive and hybrid (sometimes called mixed-mode) systems must still meet chronic and acute health standards for ventilation. This study uses a computer simulation approach to examine the energy and indoor air quality (IAQ) implications of passive and hybrid ventilation systems, in 16 California climate zones. Both uncontrolled and flow controlled passive stacks are assessed. A new hybrid ventilation system is outlined that uses an intelligent ventilation controller to minimise energy use, while ensuring chronic and acute IAQ standards are met. ASHRAE Standard 62.2-2010 – the United States standard for residential ventilation - is used as the chronic standard, and exposure limits for PM2.5, formaldehyde and NO2 are used as the acute standards.The results show that controlled passive ventilation and hybrid ventilation can be used in homes to provide equivalent IAQ to continuous mechanical ventilation, for less use of energy.

  7. Influence of Regularity of Exposure to Chronic Stress on the Pattern of Habituation of Pituitary-Adrenal Hormones, Prolactin and Glucose.

    Science.gov (United States)

    Martí; Armario

    1997-05-01

    The effect of regularity of exposure to two different chronic stressors (noise or immobilization (IMO)) on the pattern of habituation of pituitary-adrenal (PA) hormones, prolactin and glucose was evaluated in adult male rats. Animals were chronically subjected to either regular or irregular time schedule of noise (30 min/day) or IMO (2 h/day) for two weeks. The day after the last stress session the rats were killed without stress or after having been subjected to 30 min of the homotypic stressor. Whereas regular noise did not affect food intake, body weight gain or adrenal weight, irregular noise decreased body weight gain and induced a moderate adrenal hypertrophy. In addition, previous daily exposure to regular but not to irregular noise reduced both prolactin and corticosterone responses to acute noise. In contrast, glucose response to acute noise was reduced after both regular and irregular exposure to chronic noise. Either regular or irregular exposure to chronic IMO decreased food intake and body weight and increased adrenal weight to the same extent. Likewise, no influence of regularity of exposure to chronic IMO on corticosterone and prolactin responses to acute IMO was observed. However, habituation of the ACTH response to acute IMO was observed in rats subjected to chronic regular IMO, but not in rats subjected to chronic irregular IMO. Finally, acute IMO-induced hyperglycemia diminished to the same extent after regular and irregular IMO. From these results we can conclude that: first, the process of habituation of the PA axis to chronic stress is greatly dependent upon factors such as regularity of exposure to the stressor and stressor intensity, and second, the influence of regularity on the pattern of habituation to a repeated stressor is dependent on the physiological variable we are dealing with.

  8. Evaluation of the effect of chronic exposure to 137Cesium on sleep-wake cycle in rats

    International Nuclear Information System (INIS)

    Lestaevel, Philippe; Dhieux, Bernadette; Tourlonias, Elie; Houpert, Pascale; Paquet, Francois; Voisin, Philippe; Aigueperse, Jocelyne; Gourmelon, Patrick

    2006-01-01

    Since the Chernobyl accident, the most significant problem for the population living in the contaminated areas is chronic exposure by ingestion of radionuclides, notably 137 Cs, a radioactive isotope of cesium. It can be found in the whole body, including the central nervous system. The present study aimed to assess the effect of 137 Cs on the central nervous system and notably on open-field activity and the electroencephalographic pattern. Rats were exposed up to 90 days to drinking water contaminated with 137 Cs at a dosage of 400 Bq kg -1 , which is similar to that ingested by the population living in contaminated territories. At this level of exposure, no significant effect was observed on open-field activity. On the other hand, at 30 days exposure, 137 Cs decreased the number of episodes of wakefulness and slow wave sleep and increased the mean duration of these stages. At 90 days exposure, the power of 0.5-4 Hz band of 137 Cs-exposed rats was increased in comparison with controls. These electrophysiological changes may be due to a regional 137 Cs accumulation in the brain stem. In conclusion, the neurocognitive effects of 137 Cs need further evaluation and central disorders of population living in contaminated territories must be considered

  9. Evaluation of the genotoxic effects of chronic low-dose ionizing radiation exposure on nuclear medicine workers

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Ali [Department of Nuclear Medicine, Faculty of Medicine, Medical School, Ataturk University, Erzurum (Turkey)], E-mail: alibabam2001@yahoo.com; Tatar, Abdulgani; Oztas, Sitki [Department of Genetics, Faculty of Medicine, Ataturk University, 25240 Erzurum (Turkey); Seven, Bedri; Varoglu, Erhan [Department of Nuclear Medicine, Faculty of Medicine, Medical School, Ataturk University, Erzurum (Turkey); Yesilyurt, Ahmet [Department of Genetics, Faculty of Medicine, Ataturk University, 25240 Erzurum (Turkey); Ayan, Arif Kursad [Department of Nuclear Medicine, Faculty of Medicine, Medical School, Ataturk University, Erzurum (Turkey)

    2009-07-15

    Introduction: Nuclear medicine workers are occupationally exposed to chronic ionizing radiation. It is known that ionizing radiation may have damaging effects on chromosomes. In the present study, we investigated the genotoxic effects of ionizing radiation on nuclear medicine workers. We used two different indicators of genotoxicity methods: sister chromatid exchange (SCE) and micronucleus (MN). Methods: The present research was carried out using 21 nuclear medicine workers (11 females and 10 males) during two periods: during normal working conditions and after a 1-month vacation. The radiation dose varied from 1.20 to 48.56 mSv, which accumulated during the occupational exposure time between two vacations. Peripheral blood samples were taken from each subject for two distinct lymphocyte cultures (SCE and MN) in each period. Results: In nearly all subjects, SCE values increased significantly during radiation exposure compared to the postvacation period (P<.05). Similarly, MN frequencies in most of the subjects increased significantly during radiation exposure compared to the postvacation period (P<.05). Conclusions: This study revealed that both SCE and MN frequencies in most of the subjects were significantly higher during exposure to ionizing radiation than after a 1-month vacation period. However, this genotoxic effect was reversible in most of the subjects.

  10. Transcriptome Profiling of the Lungs Reveals Molecular Clock Genes Expression Changes after Chronic Exposure to Ambient Air Particles

    Directory of Open Access Journals (Sweden)

    Pengcheng Song

    2017-01-01

    Full Text Available The symptoms of asthma, breathlessness, insomnia, etc. all have relevance to pulmonary rhythmic disturbances. Epidemiology and toxicology studies have demonstrated that exposure to ambient air particles can result in pulmonary dysfunction. However, there are no data directly supporting a link between air pollution and circadian rhythm disorder. In the present study, we found that breathing highly polluted air resulted in changes of the molecular clock genes expression in lung by transcriptome profiling analyses in a rodent model. Compared to those exposed to filtered air, in both pregnant and offspring rats in the unfiltered group, key clock genes (Per1, Per2, Per3, Rev-erbα and Dbp expression level decreased and Bmal1 expression level increased. In both rat dams and their offspring, after continuous exposure to unfiltered air, we observed significant histologic evidence for both perivascular and peribronchial inflammation, increased tissue and systemic oxidative stress in the lungs. Our results suggest that chronic exposure to particulate matter can induce alterations of clock genes expression, which could be another important pathway for explaining the feedbacks of ambient particle exposure in addition to oxidative stress and inflammation.

  11. Evaluation of the genotoxic effects of chronic low-dose ionizing radiation exposure on nuclear medicine workers

    International Nuclear Information System (INIS)

    Sahin, Ali; Tatar, Abdulgani; Oztas, Sitki; Seven, Bedri; Varoglu, Erhan; Yesilyurt, Ahmet; Ayan, Arif Kursad

    2009-01-01

    Introduction: Nuclear medicine workers are occupationally exposed to chronic ionizing radiation. It is known that ionizing radiation may have damaging effects on chromosomes. In the present study, we investigated the genotoxic effects of ionizing radiation on nuclear medicine workers. We used two different indicators of genotoxicity methods: sister chromatid exchange (SCE) and micronucleus (MN). Methods: The present research was carried out using 21 nuclear medicine workers (11 females and 10 males) during two periods: during normal working conditions and after a 1-month vacation. The radiation dose varied from 1.20 to 48.56 mSv, which accumulated during the occupational exposure time between two vacations. Peripheral blood samples were taken from each subject for two distinct lymphocyte cultures (SCE and MN) in each period. Results: In nearly all subjects, SCE values increased significantly during radiation exposure compared to the postvacation period (P<.05). Similarly, MN frequencies in most of the subjects increased significantly during radiation exposure compared to the postvacation period (P<.05). Conclusions: This study revealed that both SCE and MN frequencies in most of the subjects were significantly higher during exposure to ionizing radiation than after a 1-month vacation period. However, this genotoxic effect was reversible in most of the subjects.

  12. Short-term respiratory effects of 0. 12 ppm ozone exposure in volunteers with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Linn, W.S.; Fischer, D.A.; Medway, D.A.; Anzar, U.T.; Spier, C.E.; Valencia, L.M.; Venet, T.G.; Hackney, J.D.

    1982-06-01

    Twenty-five volunteers with chronic obstructive pulmonary disease of mild to moderately severe degree underwent 1-h exposures to 0.12 ppm ozone (O/sub 2/) in purified air with intermittent mild exercise. Their responses were assessed in terms of forced expiratory performance, ear oximetry, and reported symptoms. Control studied consisted of similar exposures to purified air alone. Control studies were separated from O/sub 2/ exposures by 1 month, and the order was randomized. All studies took place in a controlled-environment chamber, and were preceded by approximately 1 h of rest in a purified-air environment. No significant disturbances in forced expiratory performance or symptoms attributable to O/sub 2/ exposure were found. A slight but significant tendency to decreased arterial hemoglobin oxygen saturation (SaO/sub 2/) during exercise in O/sub 2/ was observed. The decrement in SaO/sub 2/ with O/sub 2/ relative to clean air (mean 1.3%) was near the limit of resolution of the ear oximeter test and was detected by signal averaging, thus its physiologic or clinical significance is uncertain.

  13. Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats.

    Science.gov (United States)

    Domingues, Alexandre; Barbisan, Luis Fernando; Martins, Priscila Raquel; Spinardi-Barbisan, Ana Lúcia Tozzi

    2011-05-01

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substitute urea herbicide widely used on agricultural crops with potential mutagenic, teratogenic, reproductive and carcinogenic effects. Nonetheless, its toxic potential on the immune system needs a detailed assessment. Thus, in order to evaluate the adverse effect of this herbicide on lymphohematopoietic organs and macrophage activity, male Wistar rats were orally treated with Diuron at 125, 1250 and 2500 ppm for 14, 28 or 90 days. General signs of toxicity were observed in Diuron-treated groups (1250 and 2500 ppm), including reduced food intake and body weight gain, as well as higher relative weights for spleen, kidneys and liver (28 and 90-day toxicity studies) and elevated serum levels of ALT, albumin, total protein, creatinine and urea (28-day toxicity study). Diuron exposure caused a severe depletion of splenic white pulp compartments and cellularity, followed by a decreased number of CD4(+) T lymphocytes, increased extramedullary hematopoiesis and deposition of hemosiderin in red pulp. Despite alteration in macrophage spreading, the macrophagic activity was not significantly affected by the herbicide. Under these experimental conditions, the results suggest that Diuron exerts systemic and target-organ toxicity, mainly at higher concentration. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Chronic ethanol exposure increases voluntary home cage intake in adult male, but not female, Long-Evans rats.

    Science.gov (United States)

    Morales, Melissa; McGinnis, Molly M; McCool, Brian A

    2015-12-01

    The current experiment examined the effects of 10 days of chronic intermittent ethanol (CIE) exposure on anxiety-like behavior and home cage ethanol intake using a 20% intermittent access (M, W, F) paradigm in male and female Long-Evans rats. Withdrawal from alcohol dependence contributes to relapse in humans and increases in anxiety-like behavior and voluntary ethanol consumption in preclinical models. Our laboratory has shown that 10 days of CIE exposure produces both behavioral and neurophysiological alterations associated with withdrawal in male rats; however, we have yet to examine the effects of this exposure regime on ethanol intake in females. During baseline, females consumed more ethanol than males but, unlike males, did not show escalations in intake. Rats were then exposed to CIE and were again given intermittent access to 20% ethanol. CIE males increased their intake compared to baseline, whereas air-exposed males did not. Ethanol intake in females was unaffected by CIE exposure. Notably, both sexes expressed significantly elevated withdrawal-associated anxiety-like behavior in the plus maze. Finally, rats were injected with the cannabinoid CB1 receptor antagonist, SR141716A (0, 1, 3, 10mg/kg, i.p.) which reduced ethanol intake in both sexes. However, females appear to be more sensitive to lower doses of this CB1 receptor antagonist. Our results show that females consume more ethanol than males; however, they did not escalate their intake using the intermittent access paradigm. Unlike males, CIE exposure had no effect on drinking in females. It is possible that females may be less sensitive than males to ethanol-induced increases in drinking after a short CIE exposure. Lastly, our results demonstrate that males and females may have different pharmacological sensitivities to CB1 receptor blockade on ethanol intake, at least under the current conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    Energy Technology Data Exchange (ETDEWEB)

    Korsten, M.A.; Rosman, A.S.; Fishbein, S.; Shlein, R.D.; Goldberg, H.E.; Biener, A. (Gastrointestinal Section, Veterans Affairs Medical Center, Bronx, New York (USA))

    1991-06-01

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency.

  16. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    International Nuclear Information System (INIS)

    Korsten, M.A.; Rosman, A.S.; Fishbein, S.; Shlein, R.D.; Goldberg, H.E.; Biener, A.

    1991-01-01

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency

  17. Spatial variations in estimated chronic exposure to traffic-related air pollution in working populations: A simulation

    Directory of Open Access Journals (Sweden)

    Cloutier-Fisher Denise

    2008-07-01

    Full Text Available Abstract Background Chronic exposure to traffic-related air pollution is associated with a variety of health impacts in adults and recent studies show that exposure varies spatially, with some residents in a community more exposed than others. A spatial exposure simulation model (SESM which incorporates six microenvironments (home indoor, work indoor, other indoor, outdoor, in-vehicle to work and in-vehicle other is described and used to explore spatial variability in estimates of exposure to traffic-related nitrogen dioxide (not including indoor sources for working people. The study models spatial variability in estimated exposure aggregated at the census tracts level for 382 census tracts in the Greater Vancouver Regional District of British Columbia, Canada. Summary statistics relating to the distributions of the estimated exposures are compared visually through mapping. Observed variations are explored through analyses of model inputs. Results Two sources of spatial variability in exposure to traffic-related nitrogen dioxide were identified. Median estimates of total exposure ranged from 8 μg/m3 to 35 μg/m3 of annual average hourly NO2 for workers in different census tracts in the study area. Exposure estimates are highest where ambient pollution levels are highest. This reflects the regional gradient of pollution in the study area and the relatively high percentage of time spent at home locations. However, for workers within the same census tract, variations were observed in the partial exposure estimates associated with time spent outside the residential census tract. Simulation modeling shows that some workers may have exposures 1.3 times higher than other workers residing in the same census tract because of time spent away from the residential census tract, and that time spent in work census tracts contributes most to the differences in exposure. Exposure estimates associated with the activity of commuting by vehicle to work were

  18. Chronic occupational exposure to hexavalent chromium causes DNA damage in electroplating workers.

    Science.gov (United States)

    Zhang, Xu-Hui; Zhang, Xuan; Wang, Xu-Chu; Jin, Li-Fen; Yang, Zhang-Ping; Jiang, Cai-Xia; Chen, Qing; Ren, Xiao-Bin; Cao, Jian-Zhong; Wang, Qiang; Zhu, Yi-Min

    2011-04-12

    Occupational exposure to chromium compounds may result in adverse health effects. This study aims to investigate whether low-level hexavalent chromium (Cr(VI)) exposure can cause DNA damage in electroplating workers. 157 electroplating workers and 93 control subjects with no history of occupational exposure to chromium were recruited in Hangzhou, China. Chromium levels in erythrocytes were determined by graphite furnace atomic absorption spectrophotometer. DNA damage in peripheral lymphocytes was evaluated with the alkaline comet assay by three parameters: Olive tail moment, tail length and percent of DNA in the comet tail (tail DNA%). Urinary 8-OHdG levels were measured by ELISA. Chromium concentration in erythrocytes was about two times higher in electroplating workers (median: 4.41 μg/L) than that in control subjects (1.54 μg/L, P electroplating workers. Low-level occupational chromium exposure induced DNA damage.

  19. Chronic inorganic mercury exposure induces sex-specific changes in central TNFα expression: Importance in autism?

    OpenAIRE

    Curtis, J. Thomas; Chen, Yue; Buck, Daniel J.; Davis, Randall L.

    2011-01-01

    Mercury is neurotoxic and increasing evidence suggests that environmental exposure to mercury may contribute to neuropathologies including Alzheimer's disease and autism spectrum disorders. Mercury is known to disrupt immunocompetence in the periphery, however, little is known about the effects of mercury on neuroimmune signaling. Mercury-induced effects on central immune function are potentially very important given that mercury exposure and neuroinflammation both are implicated in certain n...

  20. Chronic exposure to sublethal hexavalent chromium affects organ histopathology and serum cortisol profile of a teleost, Channa punctatus (Bloch)

    International Nuclear Information System (INIS)

    Mishra, Ashish K.; Mohanty, Banalata

    2009-01-01

    Effects of chronic exposures (one and two months) to sublethal doses of hexavalent chromium (2 and 4 mg/L potassium dichromate) on organ histopathology and serum cortisol profile were investigated and their overall impact on growth and behavior of a teleost fish, Channa punctatus was elucidated. Histopathological lesions were distinct in the vital organs gill, kidney and liver. The gill lamellae became lifted, fused, and showed oedema. Hyperplasia and hypertrophy of lamellar epithelial cells were distinct with desquamation. Hypertrophy of epithelial cells of renal tubules and reduction in tubular lumens were observed in the trunk kidney. The atrophy of the head kidney interrenal cells and decreased serum cortisol level indicated exhaustion of interrenal activity. Hepatocyte vacuolization and shrinkage, nuclear pyknosis and increase of sinusoidal spaces were observed in the liver. Abnormal behavioral patterns and reduced growth rate were also noticed in the exposed fish. The chronic<