WorldWideScience

Sample records for acute dietary exposure

  1. Probabilistic acute dietary exposure assessments to captan and tolylfluanid using several European food consumption and pesticide concentration databases

    Boon, Polly E.; Svensson, Kettil; Moussavian, Shahnaz; van der Voet, Hilko; Petersen, Annette; Ruprich, Jiri; Debegnach, Francesca; de Boer, Waldo J.; van Donkersgoed, Gerda; Brera, Carlo; van Klaveren, Jacob D.; Busk, Leif

    2009-01-01

    Probabilistic dietary acute exposure assessments of captan and tolylfluanid were performed for the populations of the Czech Republic, Denmark, Italy, the Netherlands and Sweden. The basis for these assessments was national databases for food consumption and pesticide concentration data harmonised...... at the level of raw agricultural commodity. Data were obtained from national food consumption surveys and national monitoring programmes and organised in an electronic platform of databases connected to probabilistic software. The exposure assessments were conducted by linking national food...... consumption data either (1) to national pesticide concentration data or (2) to a pooled database containing all national pesticide concentration data. We show that with this tool national exposure assessments can be performed in a harmonised way and that pesticide concentrations of other countries can be...

  2. Probabilistic assessment of the cumulative dietary acute exposure of the population of Denmark to organophosphorus and carbamate pesticides

    Jensen, Bodil Hamborg; Petersen, Annette; Christensen, Tue

    2009-01-01

    Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables...... and cereals. The probabilistic approach was used in the assessments. Residue data obtained from the Danish monitoring programme carried out in the period 2004-2007, which included 6704 samples of fruit, vegetables and cereals, were used in the calculations. Food consumption data were obtained from...... the nationwide dietary survey conducted in 2000-2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos...

  3. Dietary exposures to selected metals and pesticides.

    MacIntosh, D L; Spengler, J D; Ozkaynak, H; Tsai, L; Ryan, P B

    1996-01-01

    Average daily dietary exposures to 11 contaminants were estimated for approximately 120,000 U.S. adults by combining data on annual diet, as measured by a food frequency questionnaire, with contaminant residue data for table-ready foods that were collected as part of the annual U.S. Food and Drug Administration Total Diet Study. The contaminants included in the analysis were four heavy metals (arsenic, cadmium, lead, mercury), three organophosphate pesticides (chlorpyrifos, diazinon, malathio...

  4. Lead dietary exposure in the European population

    European Food Safety Authority

    2012-07-01

    Full Text Available

    Lead is a natural environmental contaminant, but its use in the past in water pipes, paint and petrol increased its general presence. Food is the major source of human exposure to lead. Lead accumulates in the body and most seriously affects the developing central nervous system in young children. There is no recommended tolerable intake level as there is no evidence of thresholds for a number of critical health effects. Legislative measures have been gradually introduced to reduce exposure by removing lead from paint, food cans, water pipes and petrol. The current study examined 144,206 analytical results for lead in food collected during a nine-year period. More than half of the foods tested had levels of lead at less than detection or quantification limits. The mean lead levels varied between 0.3 µg/kg for infant follow-on formulae to 4,300 µg/kg for dietetic products with an overall median across all categories of 21.4 µg/kg. Food lead levels decreased by about 23 % between 2003 and 2010, although this should be interpreted cautiously. Mean lifetime dietary exposure was estimated at 0.68 µg/kg b.w. per day in the European population based on middle bound mean lead occurrence. Exposure was highest for toddlers and other children with 1.32 and 1.03 µg/kg b.w. per day, respectively, while the two infant surveys ranged between 0.83 and 0.91 µg/kg b.w. per day. Adult exposure was estimated at 0.50 µg/kg b.w. per day. The elderly and very elderly population groups had similar profiles to the adult age group, while adolescents had slightly higher estimated dietary exposure. Important food category contributors include bread and rolls (8.5 %, tea (6.2 %, tap water (6.1 %, potatoes and potato products (4.9 %, fermented milk products (4.2% and beer and beer-like beverages (4.1 %, although this will vary between age groups and surveys.

  5. Dietary Exposure to Benzyl Butyl Phthalate in China

    ZHANG Lei; JIANG Ding Guo; SUI Hai Xia; WU Ping Gu; LIU Ai Dong; YANG Da Jin; LIU Zhao Ping; SONG Yan; LI Ning

    2016-01-01

    ObjectiveBenzyl butyl phthalate (BBP) is a plasticizer used in food contact materials. Dietary exposure to BBP might lead to reproduction and developmental damages to human. The present paper was aimed to assess the health risk of BBP dietary exposure in Chinese population. MethodsThe BBP contents were detected in 7409 food samples from 25 foodcategories by gas chromatography-mass spectrometry operated in selected ion monitoring (SIM) mode. The dietary exposures of BBP in different age and sex groups were estimated by combining the content data with food consumption data derived from 2002 China National Nutrient and Health Survey, and evaluated according to the tolerable daily intake (TDI) of BBP established by European Food safety Agency. ResultsIt was found that BBP was undetectable in most samples and the highest level was 1.69 mg/kg detected in a vegetable oil sample. The average dietary exposure of BBP in people aged≥2 years was 1.03 μg/kgbw perday and the highest average exposure was found in 2-6 years old children (1.98 μg/kg bw perday). The BBP exposure in 7-12 months old children excessed 10% of tolerable daily intake (TDI) in worst scenario. ConclusionThe health risk of BBP dietary exposure in Chinese population is low and, considering BBP alone, there is no safety concern.

  6. Dietary exposure to inorganic arsenic in the European population

    European Food Safety Authority

    2014-03-01

    Full Text Available Arsenic is a ubiquitous metalloid present at low concentrations in rocks, soil and natural ground water. A total of 103 773 food samples (including drinking water were used to calculate dietary exposure to inorganic arsenic (iAs. Of these, 101 020 were based on total arsenic (tAs and 2 753 on iAs. Among the reported results on tAs, 66.1 % were below the limit of detection or quantification (left-censored; for the reported data on iAs the percentage of left-censored data was 41.9 %. Most of the data (92.5 % reported as tAs were converted to iAs using different approaches before calculating dietary exposure to iAs. The EFSA Comprehensive European Food Consumption Database was used to estimate chronic dietary exposure to iAs using 28 surveys from 17 European countries. According to the scenarios used for the treatment of left-censored data, mean dietary exposure among infants, toddlers and other children ranged from 0.20 to 1.37 μg/kg b.w. per day, while the 95th percentile dietary exposure estimates ranged from 0.36 to 2.09 μg/kg b.w. per day. Mean dietary exposure among the adult population (including adults, elderly and very elderly ranged from 0.09 to 0.38 μg/kg b.w. per day, and 95th percentile dietary exposure estimates ranged from 0.14 to 0.64 μg/kg b.w. per day. For all the age classes except infants and toddlers, the main contributor to dietary exposure to iAs was the food group ‘Grain-based processed products (non rice-based’, in particular, wheat bread and rolls. Other food groups that were important contributors to iAs exposure were rice, milk and dairy products (main contributor in infants and toddlers, and drinking water. The most important sources of uncertainty in the present assessment are related to the heterogeneity of the food consumption data, the conversion of tAs into iAs and to the treatment of the left-censored data.

  7. Estimating risk from acute exposures- new concepts

    Risk from acute exposures at different ages is calculated by the ICRP-60 methodology using Indian and Swedish-ICRP baseline data. The results demonstrate a considerably lower significance for exposures at higher ages. For acute exposures in the age range 0-45 years, more than half the fatality probability and more than one fourth the person-years of life lost are expressed above age 65 years. The Indian values of these parameters are a factor of 2 to 3 lower than those for the Swedish-ICRP values. The results are compared with those obtained by the Biological Effects of Ionizing Radiation (BEIR V) method. (author). 4 refs., 1 tab., 1 fig

  8. In Vivo Nanodetoxication for Acute Uranium Exposure

    Luis Guzmán

    2015-06-01

    Full Text Available Accidental exposure to uranium is a matter of concern, as U(VI is nephrotoxic in both human and animal models, and its toxicity is associated to chemical toxicity instead of radioactivity. We synthesized different PAMAM G4 and G5 derivatives in order to prove their interaction with uranium and their effect on the viability of red blood cells in vitro. Furthermore, we prove the effectiveness of the selected dendrimers in an animal model of acute uranium intoxication. The dendrimer PAMAM G4-Lys-Fmoc-Cbz demonstrated the ability to chelate the uranyl ion in vivo, improving the biochemical and histopathologic features caused by acute intoxication with uranium.

  9. Formation of acrylamide in potato products and its dietary exposure

    Mestdagh, Frédéric

    2007-01-01

    Acrylamide is formed during baking and frying of potato and cereal foodstuffs and is considered as a suspected human carcinogen. Potatoes are particularly susceptible to the formation of this process contaminant. Due to their frequent consumption, these products moreover contribute significantly to the dietary acrylamide exposure. Therefore, this study focuses on these foodstuffs. The Maillard reaction plays a key role in the formation of acrylamide. This reaction also contributes to the plea...

  10. Mathematical modeling of human dietary exposure to polychlorinated biphenyls

    Adamov, J.; Vojinovic-Miloradov, M.; Jovetic, S.; Buzarov, D. [Univ. of Novi Sad, Chemistry Dept. (Czechoslovakia)

    2004-09-15

    In this paper a mathematical model for human dietary exposure to polychlorinated biphenyls is postulated, based on the calculation of human exposure factors to PCBs via different members of the terrestrial food chain. On the basis of postulated model and experimental values for the atmospheric and soil concentration of PCBs it is possible to calculate the average daily exposure of a human organism to these ubiquitous environmental toxicants, which represent a constant threat to human health due to various chronic, developmental and genetic effects. Proposed model is the contribution to the development of exposure analysis, which is a part of a complex process of risk assessment, which gains its importance in the current situation of rapid development of industry and technology and the existence of innumerable anthropogenic hazardous chemicals.

  11. Burden of disease of dietary exposure to acrylamide in Denmark

    Jakobsen, Lea Sletting; Granby, Kit; Knudsen, Vibeke Kildegaard;

    2016-01-01

    Acrylamide (AA) is a process-contaminant that potentially increases the risk of developing cancer in humans. AA is formed during heat treatment of starchy foods and detected in a wide range of commonly consumed products. Increased focus on risk ranking and prioritization of major causes of disease...... makes it relevant to estimate the impact that exposure to chemical contaminants and other hazards in food have on health. In this study, we estimated the burden of disease (BoD) caused by dietary exposure to AA, using disability adjusted life years (DALY) as health metric.We applied an exposure...... due to exposure to AA through foods, as estimated by the most conservative approach.This result should be used to inform risk management decisions and for comparison with BoD of other food-borne hazards for prioritizing policies. However, our study shows that careful evaluation of methodological...

  12. Cumulative dietary exposure of the population of Denmark to pesticides

    Jensen, Bodil Hamborg; Petersen, Annette; Nielsen, Elsa;

    2015-01-01

    We used the Hazard Index (HI) method to carry out a cumulative risk assessment after chronic dietary exposure to all monitored pesticides in fruit, vegetables and cereals for various consumer groups in Denmark. Residue data for all the pesticides were obtained from the Danish monitoring programme...... that included processing factors and set non-detects to ½ LOR, but limited the correction (Model 3), gave the most realistic exposure estimate. With Model 3 the HI was calculated to be 0.44 for children and 0.18 for adults, indicating that there is no risk of adverse health effects following chronic...... cumulative exposure to the pesticides found in fruit, vegetables and cereals on the Danish market. The HI was below 1 even for consumers who eat more than 550 g of fruit and vegetables per day, corresponding to 1/3 of the population. Choosing Danish-produced commodities whenever possible could reduce the HI...

  13. Associations of dietary indices with biomarkers of dietary exposure and cardiovascular status among adolescents in Germany

    Truthmann Julia

    2012-10-01

    Full Text Available Abstract Background Adolescence is an important life stage for the development of dietary preferences and health behaviour. Longitudinal studies indicated that cardiovascular status in adolescence predicts cardiovascular risk marker values in adulthood. Several diet quality indices for adolescents have been developed in the past, but literature concerning associations between indices and biomarkers of dietary exposure and cardiovascular status is rather sparse. Hence, the aim of this study was to analyse associations of dietary indices with biomarkers of dietary exposure and cardiovascular status. Methods For the present analysis, data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS 2003–2006 were used. The analysis included 5,198 adolescents, aged 12 to 17 years. The Healthy Food Diversity Index (HFD, the Healthy Nutrition Score for Kids and Youth (HuSKY, the Indicator Food Index (IFI and a simple fruit/vegetable intake index were derived from food frequency questionnaire information to indicate a healthy diet. Adjusted mean values for homocysteine, uric acid, CRP, total cholesterol, HDL-C, ferritin, HbA1c, folate, vitamin B12 and BMI were calculated using complex-samples general linear models for quintiles of the different indices. Furthermore, the agreement in ranking between the different indices was calculated by weighted kappa. All statistical analyses were conducted for boys and girls separately, and were adjusted for potential confounders. Results Folate was positively associated with the HFD, the HuSKY, and fruit/vegetable intake for both boys and girls and with IFI for boys. Among girls, positive associations were seen between vitamin B12 and the IFI and between diastolic blood pressure and the IFI as well as fruit/vegetable intake. A negative association was found between homocysteine and the HFD, the HuSKY, and the IFI for both boys and girls and with fruit/vegetable intake for boys

  14. A protective effect of dietary calcium against acute waterborne cadmium uptake in rainbow trout

    The present study examined the interactions between elevated dietary calcium (as ionic Ca2+ in the form of CaCl2·2H2O) and acute waterborne Cd exposure (50 μg/l as CdNO3 for 3 h) on whole body uptake and internal distribution of newly accumulated Cd, Ca2+, and Na+ in juvenile rainbow trout (Oncorhynchus mykiss). Fish were fed with three diets 20 (control), 30 and 60 mg Ca2+/g food: for 7 days before fluxes were measured with radiotracers over a 3 h period. The two elevated Ca2+ diets reduced the whole body uptake of both Ca2+ and Cd by >50% and similarly reduced the internalization of both newly accumulated metals in most tissues, effects which reflect the shared branchial uptake route for Ca2+ and Cd. As the Ca2+ concentrations of the fluid phases of the stomach and intestinal contents were greatly elevated by the experimental diets, increased gastrointestinal Ca2+ uptake likely caused the down-regulation of the branchial Ca2+ (and Cd) uptake pathway. Waterborne Na+ uptake and internal distribution were not affected. While plasma Ca2+ surged after the first two feedings of the 60 mg Ca2+/g diet, internal homeostasis was quickly restored. Total Ca2+, Na+, and Cl- levels in tissues were not affected by diets. While dietary Ca2+ protected against waterborne Cd uptake, it did not protect against the relative inhibition of waterborne Ca2+ uptake caused by waterborne Cd. Acute exposure to 50 μg/l Cd reduced the uptake and internalization of newly accumulated Ca2+ (but not Na+) by 70% or more, regardless of diet. Since elevated dietary Ca2+ reduces waterborne Cd uptake, fish eating a Ca2+-rich invertebrate diet may be more protected against waterborne Cd toxicity in a field situation

  15. Probabilistic assessment of the cumulative dietary exposure of the population of Denmark to endocrine disrupting pesticides

    Jensen, Bodil Hamborg; Petersen, Annette; Christiansen, Sofie; Boberg, Julie; Petersen, Marta Axelstad; Herrmann, Susan Strange; Poulsen, Mette Erecius; Hass, Ulla

    2013-01-01

    The four pesticides epoxiconazole, prochloraz, procymidone and tebuconazole, are commonly used pesticides, all suspected of acting as endocrine disrupters. In the present study, we assessed the acute cumulative dietary exposure to the women of child bearing age and the general population of Denmark...... studies. Prochloraz was used as the index compound. All four pesticides increased nipple retention in male offspring, and epoxiconazole, prochloraz, and tebuconazole also increased the gestation period in pregnant rat dams. For women of childbearing age, the high-end cumulative exposure (99.9th percentile...... to these pesticides from the intake of fruit and vegetables. The assessment was carried out using the probabilistic approach combined with the relative potency factor (RPF) approach. Residue data for prochloraz, procymidone, and tebuconazole were obtained from the Danish monitoring programme 2006...

  16. Burden of disease of dietary exposure to acrylamide in Denmark.

    Jakobsen, Lea Sletting; Granby, Kit; Knudsen, Vibeke Kildegaard; Nauta, Maarten; Pires, Sara Monteiro; Poulsen, Morten

    2016-04-01

    Acrylamide (AA) is a process-contaminant that potentially increases the risk of developing cancer in humans. AA is formed during heat treatment of starchy foods and detected in a wide range of commonly consumed products. Increased focus on risk ranking and prioritization of major causes of disease makes it relevant to estimate the impact that exposure to chemical contaminants and other hazards in food have on health. In this study, we estimated the burden of disease (BoD) caused by dietary exposure to AA, using disability adjusted life years (DALY) as health metric. We applied an exposure-based approach and proposed a model of three components: an exposure, health-outcome, and DALY-module. We estimated BoD using two approaches for estimating cancer risk based on toxicological data and two approaches for estimating DALY. In Denmark, 1.8 healthy life years per 100.000 inhabitants are lost each year due to exposure to AA through foods, as estimated by the most conservative approach. This result should be used to inform risk management decisions and for comparison with BoD of other food-borne hazards for prioritizing policies. However, our study shows that careful evaluation of methodological choices and assumptions used in BoD studies is necessary before use in policy making. PMID:26845613

  17. The food metabolome: a window over dietary exposure.

    Scalbert, Augustin; Brennan, Lorraine; Manach, Claudine; Andres-Lacueva, Cristina; Dragsted, Lars O; Draper, John; Rappaport, Stephen M; van der Hooft, Justin J J; Wishart, David S

    2014-06-01

    The food metabolome is defined as the part of the human metabolome directly derived from the digestion and biotransformation of foods and their constituents. With >25,000 compounds known in various foods, the food metabolome is extremely complex, with a composition varying widely according to the diet. By its very nature it represents a considerable and still largely unexploited source of novel dietary biomarkers that could be used to measure dietary exposures with a high level of detail and precision. Most dietary biomarkers currently have been identified on the basis of our knowledge of food compositions by using hypothesis-driven approaches. However, the rapid development of metabolomics resulting from the development of highly sensitive modern analytic instruments, the availability of metabolite databases, and progress in (bio)informatics has made agnostic approaches more attractive as shown by the recent identification of novel biomarkers of intakes for fruit, vegetables, beverages, meats, or complex diets. Moreover, examples also show how the scrutiny of the food metabolome can lead to the discovery of bioactive molecules and dietary factors associated with diseases. However, researchers still face hurdles, which slow progress and need to be resolved to bring this emerging field of research to maturity. These limits were discussed during the First International Workshop on the Food Metabolome held in Glasgow. Key recommendations made during the workshop included more coordination of efforts; development of new databases, software tools, and chemical libraries for the food metabolome; and shared repositories of metabolomic data. Once achieved, major progress can be expected toward a better understanding of the complex interactions between diet and human health. PMID:24760973

  18. Assessment on Dietary Melamine Exposure from Tainted Infant Formula

    XU-DONG JIA; NING LI; ZHU-TIAN WANG; YUN-FENG ZHAO; YONG-NING WU; WEI-XING YAN

    2009-01-01

    Objective To estimate the dietary melamine exposure in Chinese infants and young children from the consumption of melamine adulterated Sanlu infant formula. Methods Four age groups of infants and young children (3, 6, 12, and 24 months) were chosen as the assessed subjects and the maximum amount of infant formula consumption was estimated based on the recommended usage level in the package insert of Sanlu infant formula and other brands. Melamine was analyzed in 111 Sanlu infant formula samples collected from the markets in Beijing and Gansu province using the LC-MS-MS with a limit of quantification of 0.05 mg/kg. Four levels of melamine concentration were chosen to estimate the dietary intakes, including the mean, median, 90th percentile, and maximum. Results The infants of 3 months had the highest intake of melamine, and with the increase of the age (month), the intake decreased. Based on the median melamine concentration (1 000 mg/kg) as an example, the melamine intakes for the infants of 3, 6, 12, and 24 months were 23.4, 21.4, 15.0, and 8.6 mg/kg bw/d, respectively. Conclusion Dietary melamine intakes from tainted Sanlu infant formula significantly exceeded the TDI level (0.2 mg/kg bw/d) recommended by the WHO Expert Meeting in 2008. However, the present assessment has some limitations including the poor representative samples, the varied melamine concentrations in the adulterated Sanlu infant formula, and other brand infant formula possibly consumed by these infants.

  19. Probabilistic assessment of the cumulative dietary exposure of the population of Denmark to endocrine disrupting pesticides.

    Jensen, Bodil Hamborg; Petersen, Annette; Christiansen, Sofie; Boberg, Julie; Axelstad, Marta; Herrmann, Susan S; Poulsen, Mette Erecius; Hass, Ulla

    2013-05-01

    The four pesticides epoxiconazole, prochloraz, procymidone and tebuconazole, are commonly used pesticides, all suspected of acting as endocrine disrupters. In the present study, we assessed the acute cumulative dietary exposure to the women of child bearing age and the general population of Denmark to these pesticides from the intake of fruit and vegetables. The assessment was carried out using the probabilistic approach combined with the relative potency factor (RPF) approach. Residue data for prochloraz, procymidone, and tebuconazole were obtained from the Danish monitoring programme 2006-2009, while residue data for epoxiconazole were obtained from the Swedish monitoring programme carried out in the period 2007-2009. Food consumption data were obtained from the Danish nationwide dietary survey conducted in 2000-2002. Relative potency factors for the four pesticides were obtained from rat studies. Prochloraz was used as the index compound. All four pesticides increased nipple retention in male offspring, and epoxiconazole, prochloraz, and tebuconazole also increased the gestation period in pregnant rat dams. For women of childbearing age, the high-end cumulative exposure (99.9th percentile) was calculated to 9% of the Adjusted Reference Value (ARV) for the effect on nipple retention and to 1% of the ARV for the effect on increased gestation period. PMID:23333574

  20. Cumulative dietary exposure to a selected group of pesticides of the triazole group in different European countries according to the EFSA guidance on probabilistic modelling

    Boon, Polly E.; van Donkersgoed, Gerda; Christodoulou, Despo;

    2015-01-01

    exposures obtained with the pessimistic model run. In this model run, animal commodities including cattle milk and different meat types, entered in the exposure calculations at the level of the maximum residue limit (MRL), contributed most to the exposure. We conclude that application of the optimistic......The practicality was examined of performing a cumulative dietary exposure assessment according to the requirements of the EFSA guidance on probabilistic modelling. For this the acute and chronic cumulative exposure to triazole pesticides was estimated using national food consumption and monitoring...

  1. Are Dietary Restraint Scales Valid Measures of Acute Dietary Restriction? Unobtrusive Observational Data Suggest Not

    Stice, Eric; Fisher, Melissa; Lowe, Michael R.

    2004-01-01

    The finding that dietary restraint scales predict onset of bulimic pathology has been interpreted as suggesting that dieting causes this eating disturbance, despite the dearth of evidence that these scales are valid measures of dietary restriction. The authors conducted 4 studies that tested whether dietary restraint scales were inversely…

  2. Dietary nitrate supplementation in COPD: An acute, double-blind, randomized, placebo-controlled, crossover trial.

    Kerley, Conor P

    2014-12-19

    The acute consumption of dietary nitrate has been shown to improve exercise capacity in athletes, healthy adults and subjects with peripheral vascular disease. Many COPD patients have reduced exercise capacity. We hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in COPD subjects.

  3. Cumulative dietary exposure to a selected group of pesticides of the triazole group in different European countries according to the EFSA guidance on probabilistic modelling.

    Boon, Polly E; van Donkersgoed, Gerda; Christodoulou, Despo; Crépet, Amélie; D'Addezio, Laura; Desvignes, Virginie; Ericsson, Bengt-Göran; Galimberti, Francesco; Ioannou-Kakouri, Eleni; Jensen, Bodil Hamborg; Rehurkova, Irena; Rety, Josselin; Ruprich, Jiri; Sand, Salomon; Stephenson, Claire; Strömberg, Anita; Turrini, Aida; van der Voet, Hilko; Ziegler, Popi; Hamey, Paul; van Klaveren, Jacob D

    2015-05-01

    The practicality was examined of performing a cumulative dietary exposure assessment according to the requirements of the EFSA guidance on probabilistic modelling. For this the acute and chronic cumulative exposure to triazole pesticides was estimated using national food consumption and monitoring data of eight European countries. Both the acute and chronic cumulative dietary exposures were calculated according to two model runs (optimistic and pessimistic) as recommended in the EFSA guidance. The exposures obtained with these model runs differed substantially for all countries, with the highest exposures obtained with the pessimistic model run. In this model run, animal commodities including cattle milk and different meat types, entered in the exposure calculations at the level of the maximum residue limit (MRL), contributed most to the exposure. We conclude that application of the optimistic model run on a routine basis for cumulative assessments is feasible. The pessimistic model run is laborious and the exposure results could be too far from reality. More experience with this approach is needed to stimulate the discussion of the feasibility of all the requirements, especially the inclusion of MRLs of animal commodities which seem to result in unrealistic conclusions regarding their contribution to the dietary exposure. PMID:25125392

  4. Chromosome aberrations and environmental exposures in acute leukemia

    Lindquist, Ragnhild Rosengren

    2009-01-01

    The aims of this thesis are to evaluate the role of environmental exposures, especially professional exposure to organic solvents and petroleum products in the etiology of acute leukemia and to investigate if there is a correlation between the exposure to a specific leukemogen factor and a clonal chromosome aberration of the leukemic cells. Papers I and II present results of a case-control study of environmental exposures, in all occupations during life-time, medical treatm...

  5. Prioritization of pesticides based on daily dietary exposure potential as determined from the SHEDS model

    A major pathway for exposure to many pesticides is through diet. The objectives were to rank pesticides by comparing their calculated daily dietary exposure as determined by EPA's Stochastic Human Exposure and Dose Simulation (SHEDS) to single pesticides for different age groups ...

  6. Dietary Exposure Assessment of Danish Consumers to Dithiocarbamate Residues in Food: a Comparison of the Deterministic and Probabilistic Approach

    Jensen, Bodil Hamborg; Andersen, Jens Hinge; Petersen, Annette;

    2008-01-01

    Probabilistic and deterministic estimates of the acute and chronic exposure of the Danish populations to dithiocarbamate residues were performed. The Monte Carlo Risk Assessment programme (MCRA 4.0) was used for the probabilistic risk assessment. Food consumption data were obtained from the...... nationwide dietary survey conducted in 2000-02. Residue data for 5721 samples from the monitoring programme conducted in the period 1998-2003 were used for dithiocarbamates, which had been determined as carbon disulphide. Contributions from 26 commodities were included in the calculations. Using the...

  7. Acute dietary nitrate supplementation does not augment submaximal forearm exercise hyperemia in healthy young men

    Kim, Jin-Kwang; Moore, David J.; Maurer, David G.; Kim-Shapiro, Daniel B.; Basu, Swati; Flanagan, Michael P.; Skulas-Ray, Ann C.; Kris-Etherton, Penny; Proctor, David N.

    2014-01-01

    Despite the popularity of dietary nitrate supplementation and the growing evidence base of its potential ergogenic and vascular health benefits, there is no direct information about its effects on exercising limb blood flow in humans. We hypothesized that acute dietary nitrate supplementation from beetroot juice would augment the increases in forearm blood flow, as well as the progressive dilation of the brachial artery, during graded handgrip exercise in healthy young men. In a randomized, d...

  8. Acute dietary nitrate supplementation enhances compensatory vasodilation during hypoxic exercise in older adults

    Casey, Darren P.; Treichler, David P; Ganger, Charles T.; Schneider, Aaron C.; Ueda, Kenichi

    2014-01-01

    We have previously demonstrated that aging reduces the compensatory vasodilator response during hypoxic exercise due to blunted nitric oxide (NO) signaling. Recent evidence suggests that NO bioavailability can be augmented by dietary nitrate through the nitrate-nitrite pathway. Thus we tested the hypothesis that acute dietary nitrate supplementation increases the compensatory vasodilator response to hypoxic exercise, particularly in older adults. Thirteen young (25 ± 1 yr) and 12 older (64 ± ...

  9. Social, dietary and clinical correlates of oedema in children with severe acute malnutrition

    Rytter, Maren Johanne Heilskov; Namusoke, Hanifa; Babirekere-Iriso, Esther;

    2015-01-01

    BACKGROUND: Severe acute malnutrition is a serious public health problem, and a challenge to clinicians. Why some children with malnutrition develop oedema (kwashiorkor) is not well understood. The objective of this study was to investigate socio-demographic, dietary and clinical correlates of oe...... have HIV infection and had fewer symptoms of other infections. Dietary diversity was lower in households of children who presented with oedema. Future research may confirm whether a causal relationship exists between these factors and nutritional oedema....

  10. Poor adherence to dietary guidelines among adult survivors of childhood acute lymphoblastic leukemia

    Robien, Kim; Ness, Kirsten K.; Klesges, Lisa M.; Baker, K. Scott; Gurney, James G.

    2008-01-01

    Recent studies indicate that survivors of childhood acute lymphocytic leukemia (ALL) are at increased risk of obesity and cardiovascular disease, conditions that healthy dietary patterns may help ameliorate or prevent. To evaluate the usual dietary intake of adult survivors of childhood ALL, food frequency questionnaire data were collected from 72 participants, and compared with the 2007 WCRF/AICR Cancer Prevention recommendations, the DASH diet, and the 2005 USDA Food Guide. Mean daily energ...

  11. Exposure assessment of adult intake of bisphenol A (BPA) with emphasis on canned food dietary exposures.

    Lorber, Matthew; Schecter, Arnold; Paepke, Olaf; Shropshire, William; Christensen, Krista; Birnbaum, Linda

    2015-04-01

    Bisphenol A (BPA) is a high-volume, synthetic compound found in epoxy resins and plastics used in food packaging. Food is believed to be a major source of BPA intake. In this study, we measured the concentration of BPA in convenience samplings of foodstuffs purchased in Dallas, Texas. Sampling entailed collection of 204 samples of fresh, frozen, and canned foods in two rounds in 2010. BPA was positive in 73% of the canned food samples, while it was found in only 7% of non-canned foods at low concentrations. The results of this food sampling program were used to calculate adult dietary intakes of BPA. A pathway approach combined food intakes, a "canned fraction" parameter which described what portion of total intake of that food came from canned products, and measured food concentrations. Dietary intakes were calculated as 12.6 ng/kg-day, of which 12.4 ng/kg-day was from canned foods. Canned vegetable intakes alone were 11.9 ng/kg-day. This dietary intake was compared to total intakes of BPA estimated from urine measurements of the National Health and Nutrition Examination Survey (NHANES). Total adult central tendency intakes ranged from 30 to 70 ng/kg-day for NHANES cycles between 2005 and 2010. Three possibilities were explored to explain the difference between these two approaches for intake estimation. Not all foods which may have been canned, particularly canned beverages such as soft drinks, were sampled in our food sampling program. Second, non-food pathways of exposure may be important for adults, including thermal paper exposures, and dust and air exposures. Finally, our canned food concentrations may not be adequately representative of canned foods in the United States; they were found to be generally lower compared to canned food concentrations measured in six other worldwide food surveys including three in North America. Our finding that canned food concentrations greatly exceeded non-canned concentrations was consistent with other studies, and

  12. Dietary BMAA Exposure in an Amyotrophic Lateral Sclerosis Cluster from Southern France

    Masseret, Estelle; Banack, Sandra; Boumédiène, Farid; Abadie, Eric; Brient, Luc; Pernet, Fabrice; Juntas-Morales, Raoul; Pageot, Nicolas; Metcalf, James; Cox, Paul; Camu, William; ,

    2013-01-01

    Background Dietary exposure to the cyanotoxin BMAA is suspected to be the cause of amyotrophic lateral sclerosis in the Western Pacific Islands. In Europe and North America, this toxin has been identified in the marine environment of amyotrophic lateral sclerosis clusters but, to date, only few dietary exposures have been described. Objectives We aimed at identifying cluster(s) of amyotrophic lateral sclerosis in the Hérault district, a coastal district from Southern France, and t...

  13. Metabolic impacts of high dietary exposure to persistent organic pollutants in mice

    Ibrahim, Mohammad Madani; Fjære, Even; Lock, Erik-Jan;

    2012-01-01

    Persistent organic pollutants (POPs) have been linked to metabolic diseases. Yet, the effects of high exposure to dietary POPs remain unclear. We therefore investigated whether elevated exposure to POPs provided by whale meat supplementation could contribute to insulin resistance. C57BL/6J mice w...... significant body burden of POPs. This indicates complex interactions between organic pollutants and nutrition in the development of metabolic disorders.......Persistent organic pollutants (POPs) have been linked to metabolic diseases. Yet, the effects of high exposure to dietary POPs remain unclear. We therefore investigated whether elevated exposure to POPs provided by whale meat supplementation could contribute to insulin resistance. C57BL/6J mice...

  14. A dietary-wide association study (DWAS of environmental metal exposure in US children and adults.

    Matthew A Davis

    Full Text Available A growing body of evidence suggests that exposure to toxic metals occurs through diet but few studies have comprehensively examined dietary sources of exposure in US populations.Our goal was to perform a novel dietary-wide association study (DWAS to identify specific dietary sources of lead, cadmium, mercury, and arsenic exposure in US children and adults.We combined data from the National Health and Nutrition Examination Survey with data from the US Department of Agriculture's Food Intakes Converted to Retail Commodities Database to examine associations between 49 different foods and environmental metal exposure. Using blood and urinary biomarkers for lead, cadmium, mercury, and arsenic, we compared sources of dietary exposure among children to that of adults.Diet accounted for more of the variation in mercury and arsenic than lead and cadmium. For instance we estimate 4.5% of the variation of mercury among children and 10.5% among adults is explained by diet. We identified a previously unrecognized association between rice consumption and mercury in a US study population--adjusted for other dietary sources such as seafood, an increase of 10 g/day of rice consumption was associated with a 4.8% (95% CI: 3.6, 5.2 increase in blood mercury concentration. Associations between diet and metal exposure were similar among children and adults, and we recapitulated other known dietary sources of exposure.Utilizing this combination of data sources, this approach has the potential to identify and monitor dietary sources of metal exposure in the US population.

  15. Development of a standard acute dietary toxicity test for the silkworm (Bombyx mori L.)

    Sun, X.; Valk, H.; Jiang, H.; Wang, X.; Yuan, S.; Zhang, Y.; Roessink, I.; Gao, X.

    2012-01-01

    Larvae of the silkworm (Bombyx mod L.) may be exposed to pesticide residues on the leaves of their food plant, the mulberry tree (Morus spp.), which can lead to adverse effects on silk production. A new acute dietary toxicity test method was evaluated as the basis for pesticide risk assessment. A se

  16. 76 FR 72404 - Pesticides: Availability of Pesticide Registration Notice Regarding the Non-Dietary Exposure Task...

    2011-11-23

    ... AGENCY Pesticides: Availability of Pesticide Registration Notice Regarding the Non-Dietary Exposure Task... registration, the Agency evaluates the potential risks to people from exposure to the pesticide in and around... the availability of a Pesticide Registration Notice (PR Notice) regarding the data development...

  17. Male Reproduction and Pesticides. Work related and dietary exposure

    Larsen, Solveig B.; Bonde, Jens Peter; Juhler, René K.;

    We found no difference in semen quality and male fecundity between traditional and organic farmers. Pesticide use by Danish farmers did not influence the different semen parameters Ø a spraying season. The dietary pesticide intake in the study group did not entail a risk of measurable reduced semen...

  18. Food Packaging and Bisphenol A and Bis(2-Ethyhexyl) Phthalate Exposure: Findings from a Dietary Intervention

    Rudel, Ruthann A.; Gray, Janet M.; Engel, Connie L.; Rawsthorne, Teresa W.; Dodson, Robin E.; Ackerman, Janet M.; Rizzo, Jeanne; Nudelman, Janet L.; Brody, Julia Green

    2011-01-01

    Background: Bisphenol A (BPA) and bis(2-ethylhexyl) phthalate (DEHP) are high-production-volume chemicals used in plastics and resins for food packaging. They have been associated with endocrine disruption in animals and in some human studies. Human exposure sources have been estimated, but the relative contribution of dietary exposure to total intake has not been studied empirically. Objectives: To evaluate the contribution of food packaging to exposure, we measured urinary BPA and phthalate...

  19. Dietary patterns among the Metro Atlanta Cohort: implications for population-based longitudinal dietary pesticide exposure and risk assessment.

    Riederer, Anne M; Pearson, Melanie A; Lu, Chensheng

    2011-01-01

    Characterizing dietary consumption patterns is critical to dietary pesticide exposure assessment. We compared consumption patterns between adults (age 18-60) in the Metro Atlanta Cohort (MAC), a longitudinal study of pesticide exposure among Atlanta residents, and US National Health and Nutrition Examination Survey (NHANES) adults. We focused on foods commonly eaten by US adults and foods likely to contain certain pesticide residues. MAC participants provided consumption data for 6 days per month for 1 year using a web-based data collection tool. We defined "percent eaters" as the percent of participants who reported eating a particular food in 24 h. We computed the NHANES weighted percent eaters and 95% confidence limits (CLs) using the 24-h dietary recall data. We calculated the MAC percent eaters for each sampling day and the percent of days this number fell below, within, or above the NHANES 95% CLs. We also re-sampled the MAC percent eaters across sampling days to find whether the resulting distribution resembled the NHANES estimate, and used the Kruskal-Wallis test to evaluate whether season affected the number of MAC eaters of a particular food on a given sampling day. In general, across all sampling days, a greater proportion of MAC participants reported eating banana, broccoli, cream, grapes, lettuce, onion, peach, pear, peas, strawberries, string beans, and tomatoes than the national estimate, whereas the proportion of apple, spinach, ketchup and white bread/roll eaters was similar, and the proportion of milk drinkers was lower. Season predicted the number of MAC peach and strawberry eaters but not other foods. The data show how a higher proportion of Atlanta adults may eat certain foods (e.g., peaches in summer or strawberries in spring) than the national average depending on season or other factors. An exposure assessment that ignored this difference could underestimate dietary pesticide intakes. PMID:20354565

  20. VISUAL SYSTEM DYSFUNCTION FOLLOWING ACUTE TRIMETHYLTIN EXPOSURE IN RATS

    Trimethyltin (TMT) has been shown to produce damage in the limbic system and several other brain areas. To date, damage to sensory systems has not been reported. The present study investigated the integrity of the visual system following acute exposure to TMT. Rats were chronical...

  1. Biomarkers of Acute Respiratory Allergen Exposure: Screening For Sensitization Potential

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

  2. PREDICTORS OF INDIVIDUAL DIFFERENCES IN ACUTE RESPONSE TO OZONE EXPOSURE

    The purposes of this study were to identify personal characteristics which predict individual differences in acute response to ozone exposure and to develop a predictive model for decrements in FEV1 as a function of ozone concentration and individual predictors. esponse and predi...

  3. Health Impacts from Acute Radiation Exposure

    Strom, Daniel J.

    2003-09-30

    Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

  4. Explanation of nurse standard of external exposure acute radiation sickness

    National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

  5. Acute behavioural dysfunctions following exposure to γ-rays

    Exposure to ionizing radiations (IR) has been reported to have many ill effects. These are manifested immediately after exposure and may persist or develop long after the incident. The severity and manifestation is dependent on the absorbed dose and type of the IR. These have been reported extensively in human subjects; especially among the victims of the accidental exposure and radiotherapy patients. Additionally, there have been a plethora of studies in animal models which support these findings, and are being used to test radio-mitigative or radio-protective strategies. The vulnerability of neuronal tissue to IR is well known, however the acute dose-dependent behavioural consequences have yet to be understood. Thus, our laboratory has been trying to decipher the dose-dependent behavioural dysfunctions which have occurred 24-72 hours post IR exposure and possible radio-protective strategies. We are utilizing mouse models of studying the behavioural processes, in a test battery conceptualized to study the affective and cognitive skills as well as motor skills of the animals. Additionally, we have observed cellular damage to different areas of the brain and subsequent correlations to behavioural dysfunctions. This has being carried out by using single cell gel electrophoresis (SCGE) and Diffusion Tensor Imaging (DTI). The findings show that after exposure to sub-lethal γ-rays, there are significant changes that occur in all the behavioural parameters. The most sensitive area has been found to be the Hippocampus as visualized by DTI and the SCGE. Consequently, short term and long term memory functions have been shown to be disrupted within 24-72 hours of exposure. Acute dysfunctions of affective functions have also been demonstrated to materialise within 24 hours post exposure. Unexpectedly, the behavioural dysfunctions were seen to be dose independent. Thus, this study provides a foundation to help decipher the acute behavioural manifestations of IR exposure

  6. Low-level arsenic exposure: Nutritional and dietary predictors in first-grade Uruguayan children.

    Kordas, Katarzyna; Queirolo, Elena I; Mañay, Nelly; Peregalli, Fabiana; Hsiao, Pao Ying; Lu, Ying; Vahter, Marie

    2016-05-01

    Arsenic exposure in children is a public health concern but is understudied in relation to the predictors, and effects of low-level exposure. We examined the extent and dietary predictors of exposure to inorganic arsenic in 5-8 year old children from Montevideo, Uruguay. Children were recruited at school; 357 were enrolled, 328 collected morning urine samples, and 317 had two 24-h dietary recalls. Urinary arsenic metabolites, i.e. inorganic arsenic (iAs), methylarsonic acid (MMA), and dimethylarsinic acid (DMA), were measured using high-performance liquid chromatography with hydride generation and inductively coupled plasma mass spectrometry (HPLC-HG-ICP-MS), and the sum concentration (U-As) used for exposure assessment. Proportions of arsenic metabolites (%iAs, %MMA and %DMA) in urine were modelled in OLS regressions as functions of food groups, dietary patterns, nutrient intake, and nutritional status. Exposure to arsenic was low (median U-As: 9.9µg/L) and household water (water As: median 0.45µg/L) was not a major contributor to exposure. Children with higher consumption of rice had higher U-As but lower %iAs, %MMA, and higher %DMA. Children with higher meat consumption had lower %iAs and higher %DMA. Higher scores on "nutrient dense" dietary pattern were related to lower %iAs and %MMA, and higher %DMA. Higher intake of dietary folate was associated with lower %MMA and higher %DMA. Overweight children had lower %MMA and higher %DMA than normal-weight children. In summary, rice was an important predictor of exposure to inorganic arsenic and DMA. Higher meat and folate consumption, diet rich in green leafy and red-orange vegetables and eggs, and higher BMI contributed to higher arsenic methylation capacity. PMID:26828624

  7. Acute differential effects of dietary protein quality on postprandial lipemia in obese non-diabetic subjects

    Holmer-Jensen, Jens; Mortensen, Lene S; Astrup, Arne;

    2013-01-01

    Non-fasting triglyceridemia is much closer associated to cardiovascular risk compared to fasting triglyceridemia. We hypothesized that there would be acute differential effects of four common dietary proteins (cod protein, whey isolate, gluten, and casein) on postprandial lipemia in obese non......-diabetic subjects. To test the hypothesis we conducted a randomized, acute clinical intervention study with crossover design. We supplemented a fat rich mixed meal with one of four dietary proteins i.e. cod protein, whey protein, gluten or casein. Eleven obese non-diabetic subjects (age: 40-68, body mass index: 30.......3-42.0 kg/m(2)) participated and blood samples were drawn in the 8-h postprandial period. Supplementation of a fat rich mixed meal with whey protein caused lower postprandial lipemia (P = .048) compared to supplementation with cod protein and gluten. This was primarily due to lower triglyceride...

  8. Acute effects of dietary constituents on motor skill and cognitive performance in athletes.

    Baker, Lindsay B; Nuccio, Ryan P; Jeukendrup, Asker E

    2014-12-01

    Performance in many sports is at least partially dependent on motor control, coordination, decision-making, and other cognitive tasks. This review summarizes available evidence about the ingestion of selected nutrients or isolated compounds (dietary constituents) and potential acute effects on motor skill and/or cognitive performance in athletes. Dietary constituents discussed include branched-chain amino acids, caffeine, carbohydrate, cocoa flavanols, Gingko biloba, ginseng, guarana, Rhodiola rosea, sage, L-theanine, theobromine, and tyrosine. Although this is not an exhaustive list, these are perhaps the most researched dietary constituents. Caffeine and carbohydrate have the greatest number of published reports supporting their ability to enhance acute motor skill and cognitive performance in athletes. At this time, there is insufficient published evidence to substantiate the use of any other dietary constituents to benefit sports-related motor skill or cognitive performance. The optimal dose and timing of caffeine and carbohydrate intake promoting enhanced motor skill and cognitive performance remain to be identified. Valid, reliable, and sensitive batteries of motor skills and cognitive tests should be developed for use in future efficacy studies. PMID:25400063

  9. Dietary exposure to persistent organic pollutants and metals among Inuit and Chukchi in Russian Arctic Chukotka

    Dudarev, Alexey A.

    2012-01-01

    Objectives. The general aim was to assess dietary exposure to selected persistent organic pollutants (POPs) and metals among Eskimo (Inuit) and Chukchi of the Chukotka Peninsula of the Russian Arctic, and to establish recommendations for exposure risk reduction. Study design. A cross-sectional evaluation of nutritional patterns of coastal and inland indigenous peoples of the Chukotka Autonomous Okrug (in 2001-2003); assessment of the levels of persistent toxic substances (PTSs) in traditional...

  10. Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

    Castellani, John W; Young, Andrew J

    2016-04-01

    Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration. PMID:26924539

  11. Human solvent exposure. Factors influencing the pharmacokinetics and acute toxicity

    Bælum, Jesper

    1991-01-01

    symptoms. The pharmacokinetics of toluene is complex and there is a large individual variation in the excretion of the metabolites. This variation can only to a limited extend be related to known variables. Intake of alcohol during exposure inhibits the metabolism of toluene and increases the internal dose...... exposed to mixtures of solvents experience an increased frequency of work related irritative and neurological symptoms although the exposure has been far below the occupational exposure limits. A series of controlled human exposure studies was carried out. Different groups of persons were exposed to the...... most frequent solvent, toluene. Toluene in alveolar air and the urinary excretion of the metabolites were measured and the acute effects of toluene were assessed by the performance in a series of test of the perceptual and psychomotor functions as well as a standardized registration of annoyance and...

  12. Toxicity levels to humans during acute exposure to hydrogen fluoride

    A literature review was conducted of the acute toxicity of hydrogen fluoride (HF) with emphasis on the effects of inhalation of gaseous HF. The data and findings of the relevant references were summarized under four categories: animal studies, controlled human studies, community exposure and industrial exposure. These were critically reviewed and then lethal concentration-time relationships were developed for humans, corresponding to LCsub(LO), LCsub(10) and LCsub(50) levels. The effects of age, health and other physiological variables on the sensitivity to HF were discussed, as well as antagonistic and synergistic effects with other substances

  13. Acute pulmonary alveolar proteinosis due to exposure to cotton dust

    Thind Gurcharan

    2009-01-01

    Full Text Available Secondary pulmonary alveolar proteinosis (PAP is rare but may occur in association with malignancy, certain infections, and exposure to inorganic or organic dust and some toxic fumes. This case report describes the second recorded case of PAP due to exposure to cotton dust. A 24-year-old man developed PAP after working as a spinner for eight years without respiratory protection. He was admitted as an emergency patient with very severe dyspnea for four months and cough for several years. Chest X-ray showed bilateral diffuse alveolar consolidation. He died 16 days later, and a diagnosis of acute pulmonary alveolar proteinosis was made at autopsy. The histopathology demonstrated alveoli and respiratory bronchioles filled with characteristic periodic acid Schiff-positive material, which also revealed birefringent bodies of cotton dust under polarized light. Secondary PAP can be fatal and present with acute respiratory failure. The occupational history and characteristic pathology can alert clinicians to the diagnosis.

  14. The role of dietary habits in human internal exposure

    The diversity of the dietary habits of the inhabitants living in the areas contaminated with long-lived radionuclides is an important factor for finding out the ways and specific features of internal dose formation of the population. The diet and structure of food consumption of different contingents of the population in several regions subjected to the radioactive accidents were studied. Using the specially developed questionnaire, we surveyed in Russia over 3000 inhabitants of the Bryansk region, and found out their food rations before the Chernobyl accident and during different time periods after it. In the Urals, we surveyed 102 inhabitants of the village Muslyumovo located on the bank of the Techa river that was contaminated as a result of releases of products of processing nuclear fuel and also more than 136 people residing in the area of the East Ural Radioactive Trace. In the North of the European part of Russia we investigated 310 local inhabitants including 114 reindeer herders. In Kazakhstan, we polled over 114 residents of the Semipalatinsk nuclear test site area, including 23 herdsmen and members of their families. The dietary habits of all investigated groups of the population strongly differ both due to climatic conditions and national and confessional traditions. Besides that, they are strongly influenced by the sources of the contamination of local food products that also differ both by radionuclide composition and by the time period elapsed since contamination of the considered areas. On the basis of the obtained results, we calculated the internal doses for the population of mentioned regions, which are in good coincidence with the data of direct measurements of radionuclides content in human body. We have determined, which products have the leading role in internal dose formation during different time periods after depositions

  15. ACUTE PRENATAL EXPOSURE TO ETHANOL AND SOCIAL BEHAVIOR: EFFECT OF AGE, SEX, AND TIMING OF EXPOSURE

    Mooney, Sandra M.; Varlinskaya, Elena I.

    2010-01-01

    During development of the central nervous system, neurons pass through critical periods of vulnerability to environmental factors. Exposure to ethanol during gastrulation or during neuronal generation results in a permanent reduction in the number of neurons in trigeminal-associated cranial nerve nuclei. Normal functioning of the trigeminal system is required for social behavior, the present study examined the effects of acute prenatal exposure to ethanol on social interactions across ontogen...

  16. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Dörr Harald; Meineke Viktor

    2011-01-01

    Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the ab...

  17. Acute differential effects of milk-derived dietary proteins on postprandial lipaemia in obese non-diabetic subjects

    Holmer-Jensen, J; Hartvigsen, M L; Mortensen, L S; Astrup, A; de Vrese, M; Holst, J J; Thomsen, C; Hermansen, Kjeld

    2012-01-01

    Postprandial lipaemia is an established risk factor for atherosclerosis. To investigate the acute effect of four milk-derived dietary proteins (alpha-lactalbumin, whey isolate, caseinoglycomacropeptide and whey hydrolysate) on postprandial lipaemia, we have conducted a randomized, acute, single-b...

  18. Reducing prenatal phthalate exposure through maternal dietary changes: results from a pilot study

    Barrett, Emily S.; Velez, Marissa; Qiu, Xing; Chen, Shaw-Ree

    2016-01-01

    Objectives Diet is a major source of exposure to certain phthalates, a class of environmental chemicals associated with endocrine disruption in animal models and humans. Several studies have attempted to lower phthalate exposure through carefully designed dietary interventions, with inconsistent results. We conducted a dietary intervention pilot study with the objective to lower phthalate exposure in low-income pregnant women, a particularly vulnerable population. Methods Ten pregnant women consumed a provided diet consisting of mostly fresh, organic foods for three days. We collected urine samples before, during, and after the intervention and conducted semi-structured interviews to assess the feasibility and acceptability of the intervention. We used repeated measures ANOVA and paired t-tests to assess differences in urinary phthalate metabolite concentrations across the study, focusing on the metabolites of di-2-ethylhexyl phthalate (DEHP), a phthalate of particular interest, and their molar sum (∑DEHP). Results Phthalate metabolite concentrations did not change appreciably during the intervention period. We observed no significant difference in ∑DEHP metabolite concentrations across the three time periods (F=0.21; adjusted p-value=0.65), and no reduction during the intervention as compared to baseline (t=−1.07, adjusted p-value=0.51). Results of interviews indicated that participants were not motivated to make dietary changes to potentially reduce chemical exposures outside of the study. Conclusions Despite the small sample size, our results suggest that promoting dietary changes to lower phthalate exposure may not be an effective public health measure. Reducing the use of phthalates in food processing and packaging may be a better solution to lowering exposure on a population level. PMID:25652062

  19. Chromosomal abnormalities and environmental exposures in acute nonlymphocytic leukemia

    Chromosomal abnormalities are present in bone marrow of approximately 50% of newly diagnostic acute nonlymphatic leukemia (ANLL) patients, but their etiologic significance, if any, is unclear. The frequency of environmental exposures, gathered by questionnaire from patients or relatives, was compared in 127 newly diagnosed ANLL patients with marrow abnormalities (AA) and 109 ANLL patients with cytogenetically normal marrow. These represented 73% of de novo patients treated at M. D. Anderson Hospital between 1976 and 1983. AA patients were more likely than NN patients to: report cytotoxic treatment for prior medical conditions, smoke cigarettes, drink alcoholic beverages, and work at occupations with possible exposure to mutagens. No statistically significant associations between aneuploidy and use of other tobacco, avocational exposure to chemicals or exposure to animals were present. Associations between specific abnormalities and prior cytotoxic therapy (deletion of chromosome 7), smoking (extra chromosome 8, inversion chromosome 16), and occupation at the time of diagnosis (translocation between chromosomes 8 and 21) were noted. No association between occupational exposure to benzene or ionizing radiation and the 6 most common chromosomal abnormalities in ANLL patients were noted, although these agents are known to be leukemogenic. Problems with interpreting the above associations, including the high nonresponse rate, a high proportion of surrogate respondents, and the large number of significance tests that were performed, are discussed. These results are consistent with those from previously reported series, and suggest that tumor-specific markers may be present for some exposures in this disease

  20. Influence of dietary vitamin E on susceptibility to ozone exposure

    Calabrese, E.J.; Victor, J.; Stoddard, M.A.

    1985-03-01

    It is widely reported that vitamin E intake may markedly reduce the occurrence of ozone-induced respiratory tract damage. Considerably less data are available concerning whether vitamin E nutritional status may affect the occurrence of ozone-induced systemic alterations such as the blood cell changes. The present study is designed to extend this previous research by evaluating the extent to which vitamin E supplementation in humans over a four week period would affect the in vitro erythrocyte susceptibility to hydrogen peroxide (H/sub 2/O/sub 2/) which is formed in whole blood following ozone exposure.

  1. Lung oxidative response after acute coal dust exposure

    Coal dust exposure can induce an acute alveolar and interstitial inflammation that can lead to chronic pulmonary diseases. The objective of this study was to describe the acute and later effects of acute coal dust exposure in lung parenchyma and the involvement of reactive oxygen species in coal dust effects. Forty-eight male Wistar rats (200-250 mg) were separated into four groups: 48 h, 7 days, 30 days, and 60 days after coal dust instillation. Gross mineral coal dust (3 mg/0.5 mL saline) was administered directly in the lungs of the treatment group by intratracheal instillation. Control animals received only saline solution (0.5 mL). Lipid peroxidation was determined by the quantity of thiobarbituric acid-reactive species (TBARS), oxidative damage to protein was obtained by the determination of carbonyl groups, the total radical-trapping antioxidant parameter (TRAP) was estimated by luminol chemoluminescence emission, catalase activity was measured by the rate of decrease in hydrogen peroxide, and superoxide dismutase activity was assayed by the inhibition of adrenaline autooxidation. Histological evaluation of coal dust-treated rats demonstrated an inflammatory infiltration after 48 h of the exposure. Initially, this was a cellular infiltration suggestive of lymphocyte infiltration with lymphoid hyperplasia that remained until 7 days after induction. This initial response was followed by a chronic inflammatory infiltration characterized by aggregates of macrophages 30 days after induction. This inflammatory response tended to resolve 60 days after induction, being similar to that of control animals. During both the acute and chronic phases of lung inflammation we observed a decrease in the TRAP in the lung of coal dust-exposed animals compared to that in control animals. We also observed an activation of superoxide dismutase 60 days after coal dust exposition. TBARS were increased 60 days after coal dust exposure and protein carbonyl groups increased at all

  2. Harmonisation of food categorisation systems for dietary exposure assessments among European children

    De Neve, Melissa; Sioen, Isabelle; Boon, Polly;

    2010-01-01

    Within the European project called EXPOCHI (Individual Food Consumption Data and Exposure Assessment Studies for Children), 14 different European individual food consumption databases of children were used to conduct harmonised dietary exposure assessments for lead, chromium, selenium and food...... colours. For this, two food categorisation systems were developed to classify the food consumption data in such a way that these could be linked to occurrence data of the considered compounds. One system served for the exposure calculations of lead, chromium and selenium. The second system was developed...... for the exposure assessment of food colours. The food categories defined for the lead, chromium and selenium exposure calculations were used as a basis for the food colour categorisation, with adaptations to optimise the linkage with the food colour occurrence data. With this work, an initial impetus...

  3. Human semen quality in relation to dietary pesticide exposure and organic diet

    Juhler, R. K.; Larsen, S. B.; Meyer, Otto A.; Jensen, N. D.; Spanò, M.; Givercman, A.; Bonde, J. P.

    1999-01-01

    The objective of the study was to corroborate or refute the hypothesis that farmers having a high intake of organic grown commodities have a high semen quality due to their expected lower level of dietary pesticides intake. Food frequency data and semen were collected from 256 farmers (171 tradit...... estimated dietary intake of 40 pesticides did not entail a risk of impaired semen quality, but precautions should be taken when generalizing this negative result to populations with a higher dietary exposure level or an intake of other groups of pesticides.......The objective of the study was to corroborate or refute the hypothesis that farmers having a high intake of organic grown commodities have a high semen quality due to their expected lower level of dietary pesticides intake. Food frequency data and semen were collected from 256 farmers (171...... mean intake of single commodities, such as rice, potato, and pork meat. The current individual dietary intake of 40 pesticides was estimated using food frequencies and generalized serving size data in combination with data on pesticide concentrations in food commodities as obtained from the National...

  4. Endocrine responses in the rhesus monkey during acute cold exposure

    Lotz, W.G.; Saxton, J.L. (Naval Aerospace Medical Research Lab., Pensacola, FL (United States))

    1991-03-11

    The authors studied five young male rhesus monkeys (Macaca mulatta), 3.4 to 6.7 kg, to determine the relationship between fluid balance hormones and urine production during acute, dry cold exposure. Each monkey served as its own control in duplicate experimental sessions at 6C or 26C. A 6-h experimental session consisted of 120 min equilibration at 26C, 120 min experimental exposure, and 120 min recovery at 26C. Urinary and venous catheters were inserted on the morning of a session. Rectal (Tre) and skin temperatures were monitored continuously. Blood samples were taken at 0, 30, 60 and 120 min of exposure, and at 60 min postexposure. Plasma was analyzed for arginine vasopressin (AVP), atrial natriuretic factor (ANF), plasma renin activity (PRA), plasma aldosterone (PA), and osmolality. Urine samples were analyzed for osmolality, electrolytes, and creatinine. Mean Tre was 1.6C lower after 120 min at 6C than at 26C. Urine volume and osmolality were not altered by cold exposure, as they are in humans and rats. Vasopressin and PA increased sharply, with mean plasma levels in monkeys exposed to cold more than threefold and tenfold, respectively, the levels in monkeys exposed at 26C. In contrast, ANF, PRA, and plasma osmolality were not significantly changed by cold exposure. The absence of a cold-induced diuresis in the monkey may be related to the marked increase in plasma AVP level.

  5. Dietary patterns and their association with acute coronary heart disease: Lessons from the REGARDS Study

    Al Suwaidi, Jassim

    2015-01-01

    Shikany et al used data from 17,418 participants in the REGARDS study, a national, population-based, longitudinal study of white and black adults aged ≥ 45 years, enrolled between 2003–2007. They examined 536 acute coronary heart disease events at follow-up (median 5.8 years) in relation to five dietary patterns (Convenience, Plant-based, Sweets, Southern, and Alcohol and Salad). After adjustment for baseline variables, the highest consumers of the Southern pattern experienced a 56% higher ha...

  6. Chronic exposure to dietary selenomethionine increases gonadal steroidogenesis in female rainbow trout

    Wiseman, Steve, E-mail: steve.wiseman@usask.ca [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Thomas, Jith K.; Higley, Eric; Hursky, Olesya [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Pietrock, Michael [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Raine, Jason C. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Giesy, John P. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); School of Biological Sciences, University of Hong Kong, Hong Kong (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 (United States); State Key Laboratory of Pollution Control and Resource Reuse and School of the Environment, Nanjing University, Nanjing (China); Janz, David M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Hecker, Markus [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5C8 (Canada)

    2011-10-15

    Selenomethionine (Se-Met) is the major dietary form of selenium (Se). Detrimental effects have been associated with exposure to elevated dietary selenium. Previous studies have demonstrated effects of Se on the endocrine system, in particular effects on cortisol and thyroid hormones. However, no information is available regarding effects of Se on sex steroid hormones. In the present study, effects of dietary exposure to an environmentally relevant concentration (4.54 mg/kg wet weight (ww)) of Se-Met for 126 days on concentrations of sex steroid hormones in blood plasma of female rainbow trout were determined. Furthermore, the molecular basis for effects of Se-Met on plasma sex steroid hormone concentrations was investigated. Concentrations of androstenedione (A), estrone (E1), and estradiol (E2) were 39.5-, 3.8-, and 12.7-fold greater in plasma of treated females than the untreated controls, respectively. Testosterone (T) was detected only in plasma of treated females. The greater E2 concentration stimulated greater transcript abundance of vitellogenin (vtg) and zona-radiata protein (zrp). Female rainbow trout exposed to Se-Met had greater transcript abundance of key steroidogenic proteins and enzymes, including peripheral benzodiazepine receptor (pbr), cytochrome P450 side-chain cleavage (P450scc), and 3{beta}-hydroxysteroid dehydrogenase (3{beta}-hsd). Exposure to Se-Met did not affect transcript abundance of luteinizing hormone (lh) or follicle stimulating hormone (fsh). Similarly, there was no change in transcript abundance of luteinizing hormone receptor (lhr) or follicle stimulating hormone receptor (fshr). Long-term exposure to dietary Se-Met has the potential to stimulate vitellogenesis in female rainbow trout by directly stimulating ovarian tissue steroidogenesis. This is the first study to report effects of Se on sex steroid hormone production in fish.

  7. Effects of Dietary Exposure to Zearalenone (ZEN) on Carp (Cyprinus carpio L.)

    Constanze Pietsch; Susanne Kersten; Hana Valenta; Sven Dänicke; Carsten Schulz; Patricia Burkhardt-Holm; Ranka Junge

    2015-01-01

    The mycotoxin zearalenone (ZEN) is frequently contaminating animal feeds including feed used in aquaculture. In the present study, the effects of dietary exposure to ZEN on carp (Cyprinus carpio L.) were investigated. ZEN at three different concentrations (low dose: 332 µg kg−1, medium dose: 621 µg kg−1 and high dose: 797 µg kg−1 final feed, respectively) was administered to juvenile carp for four weeks. Additional groups received the mycotoxin for the same time period but were fed with the u...

  8. Oxidative stress and immunologic responses following a dietary exposure to PAHs in Mya arenaria

    Gauthier-Clerc Sophie; Fournier Michel; Pellerin Jocelyne; Pichaud Nicolas; Rioux Pascal; Pelletier Émilien

    2008-01-01

    Abstract Background The aim of this research was to investigate oxidative stress and immune responses following a dietary polycyclic aromatic hydrocarbon (PAH) exposure in a marine bioindicator organism, the soft shell clam, Mya arenaria. Immune parameters in hemolymph (haemocyte number, efficiency of phagocytosis and haemocyte activity) and assessment of oxidative stress using catalase (CAT) activity and levels of malondialdehyde (MDA) performed on the digestive gland were estimated as bioma...

  9. Histopathologic alterations associated with global gene expression due to chronic dietary TCDD exposure in juvenile zebrafish.

    Qing Liu

    Full Text Available The goal of this project was to investigate the effects and possible developmental disease implication of chronic dietary TCDD exposure on global gene expression anchored to histopathologic analysis in juvenile zebrafish by functional genomic, histopathologic and analytic chemistry methods. Specifically, juvenile zebrafish were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb, and fish were sampled following 0, 7, 14, 28 and 42 d after initiation of the exposure. TCDD accumulated in a dose- and time-dependent manner and 100 ppb TCDD caused TCDD accumulation in female (15.49 ppb and male (18.04 ppb fish at 28 d post exposure. Dietary TCDD caused multiple lesions in liver, kidney, intestine and ovary of zebrafish and functional dysregulation such as depletion of glycogen in liver, retrobulbar edema, degeneration of nasal neurosensory epithelium, underdevelopment of intestine, and diminution in the fraction of ovarian follicles containing vitellogenic oocytes. Importantly, lesions in nasal epithelium and evidence of endocrine disruption based on alternatively spliced vasa transcripts are two novel and significant results of this study. Microarray gene expression analysis comparing vehicle control to dietary TCDD revealed dysregulated genes involved in pathways associated with cardiac necrosis/cell death, cardiac fibrosis, renal necrosis/cell death and liver necrosis/cell death. These baseline toxicological effects provide evidence for the potential mechanisms of developmental dysfunctions induced by TCDD and vasa as a biomarker for ovarian developmental disruption.

  10. Acute skin lesions due to localized ''hot particle'' radiation exposures

    Purpose of the studies was to determine incidence and severity of lesions resulting from localized deposition of dose to the skin from small (2 at 70μm depth) from isotopes having max beta particle energies from about 0.3-3 MeV. Incidence of erythema and scabs (indicating ulceration) were scored routinely for up to 71 days post-irradiation. Responses followed normal probability distributions, and thus, no true threshold could be defined. Ten and 50% incidence rates were deduced using probit analyses. Lowest dose producing 10% incidence was about 1 Gy for exposures to Yb-175 (0.5 MeV max energy) beta particles. Severity of lesions was estimated using diameters and persistence. From preliminary considerations of probability of induction, size, and persistence of acute lesions, a special limit for hot particle exposures in the range of 5-50 Gy may be reasonable, with an action level between about 1 Gy and the limit

  11. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Dörr Harald

    2011-11-01

    Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  12. Impact of dietary exposure to food contaminants on the risk of Parkinson's disease

    Petersen, Maria Skaalum; Halling, Jónrit; Bech, Sára;

    2008-01-01

    , pesticides and metals also suggested an increased risk for PD. Current serum concentrations of summation operator PCB and related contaminants suggested slightly increased ORs, although only beta-hexachlorocyclohexane (beta-HCH) was statistically significant. Increased intake of whale meat and blubber...... in adult life was significantly associated with PD, thus suggesting a positive association between previous exposure to marine food contaminants and development of PD....... were examined in this case-control study in the Faroe Islands. Blood and hair samples were collected and a questionnaire recorded lifetime information on residence, dietary habits, smoking history, and occupational exposure to solvents, pesticides, and metals. Both unconditional and conditional...

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

    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

  14. Relationships between children's exposure to ethnic produce and their dietary behaviors.

    Chen, Qiong; Goto, Keiko; Wolff, Cindy; Zhao, Yanling

    2015-04-01

    The current study examined relationships between children's ethnic produce exposure and healthy dietary practices among Latino, Hmong and non-Hispanic white children. One hundred Latino, 100 Hmong, and 92 non-Hispanic white parents of children ages 5-8 years old in northern California completed a cross-sectional survey. Children's exposure to ethnic produce from Hmong and Latino cultures, overall fruit and vegetable consumption, and fast food and ethnic restaurant use were measured. The Kruskal-Wallis and Mann-Whitney tests were used to compare variables across different ethnic groups. Spearman's correlation was used to assess the relationship between variables. Children's overall ethnic produce exposure, as well as exposure to produce from other cultures, was significantly correlated with overall fruit and vegetable consumption. There was a marginal (p = 0.053) negative association between ethnic produce exposure and fast food restaurant use among Latino children. These findings suggest that promoting ethnic produce is an effective strategy for enhancing healthy dietary practices among children. PMID:24817576

  15. An assessment of dietary exposure to glyphosate using refined deterministic and probabilistic methods.

    Stephenson, C L; Harris, C A

    2016-09-01

    Glyphosate is a herbicide used to control broad-leaved weeds. Some uses of glyphosate in crop production can lead to residues of the active substance and related metabolites in food. This paper uses data on residue levels, processing information and consumption patterns, to assess theoretical lifetime dietary exposure to glyphosate. Initial estimates were made assuming exposure to the highest permitted residue levels in foods. These intakes were then refined using median residue levels from trials, processing information, and monitoring data to achieve a more realistic estimate of exposure. Estimates were made using deterministic and probabilistic methods. Exposures were compared to the acceptable daily intake (ADI)-the amount of a substance that can be consumed daily without an appreciable health risk. Refined deterministic intakes for all consumers were at or below 2.1% of the ADI. Variations were due to cultural differences in consumption patterns and the level of aggregation of the dietary information in calculation models, which allows refinements for processing. Probabilistic exposure estimates ranged from 0.03% to 0.90% of the ADI, depending on whether optimistic or pessimistic assumptions were made in the calculations. Additional refinements would be possible if further data on processing and from residues monitoring programmes were available. PMID:27371367

  16. Assessing infant exposure to persistent organic pollutants via dietary intake in Australia.

    Toms, Leisa-Maree Leontjew; Hearn, Laurence; Mueller, Jochen F; Harden, Fiona A

    2016-01-01

    Persistent organic pollutants (POPs) including polybrominated diphenyl ethers (PBDEs); organochlorine pesticides (OCPs); and polychlorinated biphenyls (PCBs) persist in the environment, bioaccumulate, and pose a risk of causing adverse human health effects. Typically, exposure assessments undertaken by modeling existing intake data underestimate the concentrations of these chemicals in infants. This study aimed to determine concentrations of POPs in infant foods, assess exposure via dietary intake and compare this to historical exposure. Fruit purees, meat and vegetables, dairy desserts, cereals and jelly foods (n = 33) purchased in 2013 in Brisbane, Australia were analyzed. For OCPs and PCBs, concentrations ranged up to 95 pg/g fw and for PBDEs up to 32 pg/g fw with most analytes below the limit of detection. Daily intake is dependent on type and quantity of foods consumed. Consumption of a 140 g meal would result in intake ranging from 0 to 4.2 ng/day, 4.4 ng/day and 13.3 ng/day, for OCPs, PBDEs and PCBs, respectively. PBDEs were detected in 3/33 samples, OCPs in 9/33 samples and PCBs in 13/33 samples. Results from this study indicate exposure for infants via dietary (in contrast to dust and breast milk) intake in Australia contribute only a minor component to total exposure. PMID:26710981

  17. Pattern of mercury allocation into egg components is independent of dietary exposure in Gentoo penguins.

    Brasso, Rebecka L; Abel, Stephanie; Polito, Michael J

    2012-04-01

    Avian eggs have become one of the most common means of evaluating mercury contamination in aquatic and marine environments and can serve as reliable indicators of dietary mercury exposure. We investigated patterns of mercury deposition into the major components of penguin eggs (shell, membrane, albumen, and yolk) using the Gentoo penguin (Pygoscelis papua) as a model species. Eggs were collected from both wild and captive populations of Gentoo penguins to compare the allocation of mercury into individual egg components of birds feeding at disparate trophic positions as inferred by stable isotope analysis. Mercury concentrations in captive penguins were an order of magnitude higher than in wild birds, presumably because the former were fed only fish at a higher trophic position relative to wild penguins that fed on a diet of 72-93% krill (Euphausia spp.). Similar to previous studies, we found the majority of total egg mercury sequestered in the albumen (92%) followed by the yolk (6.7%) with the lowest amounts in the shell (0.9%) and membrane (0.4%). Regardless of dietary exposure, mercury concentrations in yolk and membrane, and to a lesser degree shell, increased with increasing albumen mercury (used as a proxy for whole-egg mercury), indicating that any component, in the absence of others, may be suitable for monitoring changes in dietary mercury. Because accessibility of egg tissues in the wild varies, the establishment of consistent relationships among egg components will facilitate comparisons with any other study using eggs to assess dietary exposure to mercury. PMID:22002784

  18. THERMOREGULATION IN THE RAT DURING CHRONIC, DIETARY EXPOSURE TO CHLORPYRIFOS, AN ORGANOPHOSPHATE INSECTICIDE.

    Administration of chlorpyrifos (CHP) at a dose of 25 to 80 mg/kg (p.o.) To rats results in hypothermia followed by a fever lasting for several days. To understand if chronic, low level exposure to CHP affects thermoregulation in a comparable manner to acute administration, male L...

  19. Acute dietary nitrate supplementation does not augment submaximal forearm exercise hyperemia in healthy young men.

    Kim, Jin-Kwang; Moore, David J; Maurer, David G; Kim-Shapiro, Daniel B; Basu, Swati; Flanagan, Michael P; Skulas-Ray, Ann C; Kris-Etherton, Penny; Proctor, David N

    2015-02-01

    Despite the popularity of dietary nitrate supplementation and the growing evidence base of its potential ergogenic and vascular health benefits, there is no direct information about its effects on exercising limb blood flow in humans. We hypothesized that acute dietary nitrate supplementation from beetroot juice would augment the increases in forearm blood flow, as well as the progressive dilation of the brachial artery, during graded handgrip exercise in healthy young men. In a randomized, double-blind, placebo-controlled crossover study, 12 young (22 ± 2 years) healthy men consumed a beetroot juice (140 mL Beet-It Sport, James White Juice Company) that provided 12.9 mmol (0.8 g) of nitrate or placebo (nitrate-depleted Beet-It Sport) on 2 study visits. At 3 h postconsumption, brachial artery diameter, flow, and blood velocity were measured (Doppler ultrasound) at rest and during 6 exercise intensities. Nitrate supplementation raised plasma nitrate (19.5-fold) and nitrite (1.6-fold) concentrations, and lowered resting arterial pulse wave velocity (PWV) versus placebo (all p < 0.05), indicating absorption, conversion, and a biological effect of this supplement. The supplement-associated lowering of PWV was also negatively correlated with plasma nitrite (r = -0.72, p = 0.0127). Despite these systemic effects, nitrate supplementation had no effect on brachial artery diameter, flow, or shear rates at rest (all p ≥ 0.28) or during any exercise workload (all p ≥ 0.18). These findings suggest that acute dietary nitrate supplementation favorably modifies arterial PWV, but does not augment blood flow or brachial artery vasodilation during nonfatiguing forearm exercise in healthy young men. PMID:25536008

  20. Dietary exposure to 5-hydroxymethylfurfural from Norwegian food and correlations with urine metabolites of short-term exposure.

    Husøy, T; Haugen, M; Murkovic, M; Jöbstl, D; Stølen, L H; Bjellaas, T; Rønningborg, C; Glatt, H; Alexander, J

    2008-12-01

    5-Hydroxymethylfurfural (HMF) is formed in carbohydrate-rich food during acid-catalysed dehydration and in the Maillard reaction from reducing sugars. HMF is found in mg quantities per kg in various foods. HMF is mainly metabolised to 5-hydroxymethyl-2-furoic acid (HMFA), but unknown quantities of the mutagenic 5-sulphoxymethylfurfural (SMF) may also be formed, making HMF potentially hazardous to humans. We determined the HMF content in Norwegian food items and estimated the dietary intake of HMF in 53 volunteers by means of 24h dietary recall. The estimated intakes of HMF were correlated with urinary excretion of HMFA. Coffee, prunes, dark beer, canned peaches and raisins had the highest levels of HMF. The 95th percentile of the estimated daily dietary intake of HMF and the 24h urinary excretion of HMFA were 27.6 and 28.6mg, respectively. Coffee, dried fruit, honey and alcohol were identified as independent determinants of urinary HMFA excretion. Most participants had lower estimated HMF intake than the amount of HMFA excreted in urine. In spite of this there was a significant correlation (r=0.57, PHMF intake and urinary HMFA. Further studies are needed to reveal alternative sources for HMF exposure. PMID:18929614

  1. Estimation of dietary exposure to acrylamide of Polish teenagers from an urban environment.

    Wyka, Joanna; Tajner-Czopek, Agnieszka; Broniecka, Anna; Piotrowska, Ewa; Bronkowska, Monika; Biernat, Jadwiga

    2015-01-01

    The aim of this study was to evaluate the dietary exposure to acrylamide (AA) in a group of teenagers (n = 261) from an urban environment. The intake of AA from food was estimated based on a 7-day food record diary (consecutive days). The food rations obtained (n = 1827) were used to calculate the amounts of the consumed food products, which were the main sources of AA. In the case of girls, the estimated dietary intake of AA per kg body weight (BW) amounted to 0.09 µg/kg BW/day (50th percentile), 0.32 µg/kg BW/day (75th percentile) and 1.04 µg/kg BW/day (95th percentile), and among boys it was 0.13, 0.41, and 1.18 µg/kg BW/day, respectively. The main sources of AA exposure were French fries, potato crisps, corn flakes, bread and salty sticks. The lowest values for margin of exposure (MOE) were calculated for the P95th percentiles of exposure, and ranged from 152 to 173. PMID:25445510

  2. Acute effects of acrolein in human volunteers during controlled exposure

    Dwivedi, Aishwarya M.; Johanson, Gunnar; Lorentzen, Johnny C.; Palmberg, Lena; Sjögren, Bengt; Ernstgård, Lena

    2015-01-01

    Abstract Context: Acrolein is a reactive aldehyde mainly formed by combustion. The critical effect is considered to be irritation of the eyes and airways; however, the scarce data available make it difficult to assess effect levels. Objective: The aim of the study was to determine thresholds for acute irritation for acrolein. Methods: Nine healthy volunteers of each sex were exposed at six occasions for 2 h at rest to: clean air, 15 ppm ethyl acetate (EA), and 0.05 ppm and 0.1 ppm acrolein with and without EA (15 ppm) to mask the potential influence of odor. Symptoms related to irritation and central nervous system effects were rated on 100-mm Visual Analogue Scales. Results: The ratings of eye irritation were slightly but significantly increased during exposure to acrolein in a dose-dependent manner (p acrolein alone but not during any of the other five exposure conditions. Conclusion: Based on subjective ratings, the present study showed minor eye irritation by exposure to 0.1 ppm acrolein. PMID:26635308

  3. Assessing dietary exposure to cadmium in a metal recycling community in Vietnam: Age and gender aspects

    This study estimates the dietary exposure to cadmium (Cd), and associated potential health risks, for individuals living and working in a metal recycling community (n = 132) in Vietnam in comparison to an agricultural (reference) community (n = 130). Individual-level exposure to Cd was estimated through analysis of staple foodstuffs combined with information from a food frequency questionnaire. Individual-level exposure estimates were compared with published ‘safe’ doses to derive a Hazard Quotient (HQ) for each member of the study population. Looking at the populations as a whole, there were no significant differences in the diets of the two villages. However, significantly more rice was consumed by working age adults (18–60 years) in the recycling village compared to the reference village (p 3), while 20% of adult participants from the reference village had an HQ > 1. We found an elevated health risk from dietary exposure to Cd in the metal recycling village compared to the reference community. WHO standard of 0.4 mg Cd/kg rice may not be protective where people consume large amounts of rice/have relatively low body weight. - Highlights: ► First individual-level risk assessment of cadmium in recycling villages of Vietnam. ► Dietary analysis undertaken for a recycling community and an agricultural community. ► No significant differences were found between the diets of the two populations. ► 87% of people in the recycling community had elevated health risk. ► WHO standard (0.4 mg Cd/kg rice) may not be protective for rice-based cultures.

  4. Dietary exposure to mycotoxins of the Hong Kong adult population from a Total Diet Study.

    Yau, Arthur Tin-Chung; Chen, Melva Yung-Yung; Lam, Chi-Ho; Ho, Yuk-Yin; Xiao, Ying; Chung, Stephen Wai-Cheung

    2016-06-01

    Dietary exposure of Hong Kong adults to mycotoxins and their metabolites including aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FNs), deoxynivalenol (DON), acetyldeoxynivalenols (AcDONs) and zearalenone (ZEA) was estimated using the Total Diet Study (TDS) approach to assess the associated health risk to the local people. Sixty commonly consumed food items, collected in four seasons, were sampled and prepared as consumed. These mycotoxins were primarily found at low levels. The highest mean levels (upper bound) were: AFs, 1.50 µg kg(-)(1) in legumes, nuts and seed; OTA, 0.22 µg kg(-)(1) in sugars and confectionery; FNs, 9.76 µg kg(-)(1) in cereals and their products; DON and AcDONs, 33.1 µg kg(-)(1) in cereals and their products; and ZEA, 53.8 µg kg(-)(1) in fats and oils. The estimated dietary exposures of Hong Kong adults to the mycotoxins analysed were well below the respective health-based guidance values, where available. For AFs, the upper-bound exposure for high consumers is 0.0049 µg kg bw(-)(1) day(-)(1), which was estimated to contribute to about 7.7 (mycotoxins were: ochratoxin A, 3.6-9.2%; fumonisins, 0.04-8.5%; deoxynivalenol and acetyldeoxynivalenols, 21.7-28.2%; and zearalenone 3.3-34.5%. The findings indicate that dietary exposures to all the mycotoxins analysed in this study were unlikely to pose an unacceptable health risk to the Hong Kong population. PMID:27144988

  5. Self-reported acute health symptoms and exposure to companion animals

    Background: In order to understand the etiological burden of disease associated with acute health symptoms (e.g. gastrointestinal [GI], respiratory, dermatological), it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar ...

  6. Acute symptoms during non-inhalation exposure to combinations of toluene, trichloroethylene, and n-hexane

    Bælum, Jesper

    1999-01-01

    To study the acute effect of exposure to a mixture of three commonly used solvents in humans using a route of exposure not involving the nose and lungs, in this case a gastrointestinal application....

  7. A systematic review on food lead concentration and dietary lead exposure in China

    Jin Yingliang; Liu Pei; Wu Yongning; Min Jie; Wang Cannan; Sun Jinfang; Zhang Yafei

    2014-01-01

    Background By synthesizing results from primary studies,systematic review can provide empirical information of concerned problems.This study aimed to review the available surveillance data from studies reporting the contamination surveillance of food lead in China.Methods Relevant studies were identified by systematically searching Chinese Biological Medicine Database and China National Knowledge Infrastructure using the key term of "lead" for surveillance data published in Chinese between 2006 and 2012.To avoid potential selection bias,all articles were evaluated by two independent reviewers,and the disagreements were resolved by discussion or the third author was asked to arbitrate.Results Among 269 identified publications on surveillance data of lead in food,43 articles met the defined inclusion criteria.The food samples were divided into 11 groups (cereal grains and pulses,fish,eggs,vegetables,meat,edible fungi,milk and dairy products,fruits,offal,tea and preserved egg).Surveillance data of publications were reviewed to calculate the weighted mean and rate exceeding maximum levels.Our results indicated that the highest lead concentration was 1.937 mg/kg in tea.The total pementage of samples exceeding the maximum levels was 5.57%.Dietary exposure to lead was assessed by combining the weighted mean concentration of surveillance data with national consumption data in 2002.In this review,dietary intake of lead was 1.232 μg/kg b.w./day.Conclusion Further control measures should be taken to reduce exposure to lead,from both dietary and non-dietary sources.

  8. Dose-response relationships of acute exposure to sulfur dioxide

    Acute toxicity effects of sulphur dioxide are reviewed, and the derivation of a dose-lethality curve (presented as LC50 vs. time) for human exposure to sulphur dioxide is attempted for periods ranging from ten seconds to two hours. As an aid to assessment of the hazards involved in operating heavy water manufacturing facilities, the fact that sulphur dioxide would be produced by the combustion of hydrogen sulphide was briefly considered in an appendix. It is suggested that sulphuric acid, a much more toxic substance than sulphur dioxide, may also be formed in such an event. It is concluded, therefore, that an overall hazard evaluation may have to address the contributory effects of sulphuric acid. (author)

  9. Dietary phthalate exposure in pregnant women and the impact of consumer practices.

    Serrano, Samantha E; Karr, Catherine J; Seixas, Noah S; Nguyen, Ruby H N; Barrett, Emily S; Janssen, Sarah; Redmon, Bruce; Swan, Shanna H; Sathyanarayana, Sheela

    2014-06-01

    Phthalates are ubiquitous endocrine-disrupting chemicals that are contaminants in food and contribute to significant dietary exposures. We examined associations between reported consumption of specific foods and beverages and first trimester urinary phthalate metabolite concentrations in 656 pregnant women within a multicenter cohort study, The Infant Development and Environment Study (TIDES), using multivariate regression analysis. We also examined whether reported use of ecofriendly and chemical-free products was associated with lower phthalate biomarker levels in comparison to not following such practices. Consumption of one additional serving of dairy per week was associated with decreases of 1% in the sum of di-2-ethylhexyl phthalate (DEHP) metabolite levels (95% CI: -2.0, -0.2). Further, participants who reported sometimes eating homegrown food had monoisobutyl phthalate (MiBP) levels that were 16.6% lower (95% CI: -29.5, -1.3) in comparison to participants in the rarely/never category. In contrast to rarely/never eating frozen fruits and vegetables, participants who reported sometimes following this practice had monobenzyl phthalate (MBzP) levels that were 21% higher (95% CI: 3.3, 41.7) than rarely/ever respondents. Future study on prenatal dietary phthalate exposure and the role of consumer product choices in reducing such exposure is needed. PMID:24927036

  10. Dietary Phthalate Exposure in Pregnant Women and the Impact of Consumer Practices

    Serrano, Samantha E.; Karr, Catherine J.; Seixas, Noah S.; Nguyen, Ruby H. N.; Barrett, Emily S.; Janssen, Sarah; Redmon, Bruce; Swan, Shanna H.; Sathyanarayana, Sheela

    2014-01-01

    Phthalates are ubiquitous endocrine-disrupting chemicals that are contaminants in food and contribute to significant dietary exposures. We examined associations between reported consumption of specific foods and beverages and first trimester urinary phthalate metabolite concentrations in 656 pregnant women within a multicenter cohort study, The Infant Development and Environment Study (TIDES), using multivariate regression analysis. We also examined whether reported use of ecofriendly and chemical-free products was associated with lower phthalate biomarker levels in comparison to not following such practices. Consumption of one additional serving of dairy per week was associated with decreases of 1% in the sum of di-2-ethylhexyl phthalate (DEHP) metabolite levels (95% CI: −2.0, −0.2). Further, participants who reported sometimes eating homegrown food had monoisobutyl phthalate (MiBP) levels that were 16.6% lower (95% CI: −29.5, −1.3) in comparison to participants in the rarely/never category. In contrast to rarely/never eating frozen fruits and vegetables, participants who reported sometimes following this practice had monobenzyl phthalate (MBzP) levels that were 21% higher (95% CI: 3.3, 41.7) than rarely/ever respondents. Future study on prenatal dietary phthalate exposure and the role of consumer product choices in reducing such exposure is needed. PMID:24927036

  11. Dietary Phthalate Exposure in Pregnant Women and the Impact of Consumer Practices

    Samantha E. Serrano

    2014-06-01

    Full Text Available Phthalates are ubiquitous endocrine-disrupting chemicals that are contaminants in food and contribute to significant dietary exposures. We examined associations between reported consumption of specific foods and beverages and first trimester urinary phthalate metabolite concentrations in 656 pregnant women within a multicenter cohort study, The Infant Development and Environment Study (TIDES, using multivariate regression analysis. We also examined whether reported use of ecofriendly and chemical-free products was associated with lower phthalate biomarker levels in comparison to not following such practices. Consumption of one additional serving of dairy per week was associated with decreases of 1% in the sum of di-2-ethylhexyl phthalate (DEHP metabolite levels (95% CI: −2.0, −0.2. Further, participants who reported sometimes eating homegrown food had monoisobutyl phthalate (MiBP levels that were 16.6% lower (95% CI: −29.5, −1.3 in comparison to participants in the rarely/never category. In contrast to rarely/never eating frozen fruits and vegetables, participants who reported sometimes following this practice had monobenzyl phthalate (MBzP levels that were 21% higher (95% CI: 3.3, 41.7 than rarely/ever respondents. Future study on prenatal dietary phthalate exposure and the role of consumer product choices in reducing such exposure is needed.

  12. Relation between dietary acrylamide exposure and biomarkers of internal dose in Canadian teenagers.

    Brisson, Benjamin; Ayotte, Pierre; Normandin, Louise; Gaudreau, Éric; Bienvenu, Jean-François; Fennell, Timothy R; Blanchet, Carole; Phaneuf, Denise; Lapointe, Caroline; Bonvalot, Yvette; Gagné, Michelle; Courteau, Marilène; Snyder, Rodney W; Bouchard, Michèle

    2014-01-01

    Acrylamide (AA) is a probable human carcinogen found in several foods. Little information is available regarding exposure of adolescents, a subgroup potentially consuming more AA-rich foods. We investigated the relationship between dietary AA intake and levels of biomarkers of exposure (urinary metabolites and hemoglobin adducts) in 195 non-smoking teenagers of Montreal Island aged 10-17 years. Dietary habits and personal characteristics were documented by questionnaire. AA and its metabolites were quantified in 12-h urine collections by LC-MS/MS. Hemoglobin adducts from 165 blood samples were also analyzed by LC-MS/MS. Most prevalent urinary metabolites were NACP and NACP-S, with respective geometric mean concentrations of 31.2 and 14.2 μmol/mol creatinine. Geometric mean concentrations of AAVal and GAVal (hemoglobin adducts of AA and glycidamide (GA) with N-terminal valine residues) were 45.4 and 45.6 pmol/g globin, respectively. AA intake during the 2 days before urine collection was a significant predictor of NACP+NACP-S urinary concentrations (P<0.0001). AA intakes during the month before blood collection (P<0.0001) and passive smoking (P<0.05) were associated with adduct levels. Levels of hemoglobin adducts were above biomonitoring equivalent values corresponding to a 1 × 10(-4) excess cancer risk, which may indicate the need to reduce AA exposure in the population. PMID:23756700

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

    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.

  14. High Dietary Iron and Radiation Exposure Increase Biomarkers of Oxidative Stress in Blood and Liver of Rats

    Morgan, Jennifer L. L.; Theriot, Corey A.; Wu, Honglu; Smith, Scott M.; Zwart, Sara R.

    2012-01-01

    Radiation exposure and increased iron (Fe) status independently cause oxidative damage that can result in protein, lipid, and DNA oxidation. During space flight astronauts are exposed to both increased radiation and increased Fe stores. Increased body Fe results from a decrease in red blood cell mass and the typically high Fe content of the food system. In this study we investigated the combined effects of radiation exposure (0.375 Gy of Cs-137 every other day for 16 days for a total of 3 Gy) and high dietary Fe (650 mg Fe/kg diet compared to 45 mg Fe/kg for controls) in Sprague-Dawley rats (n=8/group). Liver and serum Fe were significantly increased in the high dietary Fe groups. Likewise, radiation treatment increased serum ferritin and Fe concentrations. These data indicate that total body Fe stores increase with both radiation exposure and excess dietary Fe. Hematocrit decreased in the group exposed to radiation, providing a possible mechanism for the shift in Fe indices after radiation exposure. Markers of oxidative stress were also affected by both radiation and high dietary Fe, evidenced by increased liver glutathione peroxidase (GPX) and serum catalase as well as decreased serum GPX. We thus found preliminary indications of synergistic effects of radiation exposure and increased dietary Fe, warranting further study. This study was funded by the NASA Human Research Project.

  15. Considerations when using longitudinal cohort studies to assess dietary exposure to inorganic arsenic and chronic health outcomes.

    Scrafford, Carolyn G; Barraj, Leila M; Tsuji, Joyce S

    2016-07-01

    Dietary arsenic exposure and chronic health outcomes are of interest, due in part to increased awareness and data available on inorganic arsenic levels in some foods. Recent concerns regarding levels of inorganic arsenic, the primary form of arsenic of human health concern, in foods are based on extrapolation from adverse health effects observed at high levels of inorganic arsenic exposure; the potential for the occurrence of these health effects from lower levels of dietary inorganic arsenic exposure has not been established. In this review, longitudinal cohort studies are evaluated for their utility in estimating dietary inorganic arsenic exposure and quantifying statistically reliable associations with health outcomes. The primary limiting factor in longitudinal studies is incomplete data on inorganic arsenic levels in foods combined with the aggregation of consumption of foods with varying arsenic levels into a single category, resulting in exposure misclassification. Longitudinal cohort studies could provide some evidence to evaluate associations of dietary patterns related to inorganic arsenic exposure with risk of arsenic-related diseases. However, currently available data from longitudinal cohort studies limit causal analyses regarding the association between inorganic arsenic exposure and health outcomes. Any conclusions should therefore be viewed with knowledge of the analytical and methodological limitations. PMID:27155067

  16. Repeated exposure to conditioned fear stress increases anxiety and delays sleep recovery following exposure to an acute traumatic stressor

    Benjamin N Greenwood

    2014-10-01

    Full Text Available Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep-wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by humans, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to either no, mild (10, or severe (100 acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced REM and NREM sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep / wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep / wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders.

  17. Risk Assessment on Dietary Exposure to Aflatoxin B1 in Post-Harvest Peanuts in the Yangtze River Ecological Region

    Xiaoxia Ding; Linxia Wu; Peiwu Li; Zhaowei Zhang; Haiyan Zhou; Yizhen Bai; Xiaomei Chen; Jun Jiang

    2015-01-01

    Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecol...

  18. Dietary BMAA exposure in an amyotrophic lateral sclerosis cluster from southern France.

    Estelle Masseret

    Full Text Available BACKGROUND: Dietary exposure to the cyanotoxin BMAA is suspected to be the cause of amyotrophic lateral sclerosis in the Western Pacific Islands. In Europe and North America, this toxin has been identified in the marine environment of amyotrophic lateral sclerosis clusters but, to date, only few dietary exposures have been described. OBJECTIVES: We aimed at identifying cluster(s of amyotrophic lateral sclerosis in the Hérault district, a coastal district from Southern France, and to search, in the identified area(s, for the existence of a potential dietary source of BMAA. METHODS: A spatio-temporal cluster analysis was performed in the district, considering all incident amyotrophic lateral sclerosis cases identified from 1994 to 2009 by our expert center. We investigated the cluster area with serial collections of oysters and mussels that were subsequently analyzed blind for BMAA concentrations. RESULTS: We found one significant amyotrophic lateral sclerosis cluster (p = 0.0024, surrounding the Thau lagoon, the most important area of shellfish production and consumption along the French Mediterranean coast. BMAA was identified in mussels (1.8 µg/g to 6.0 µg/g and oysters (0.6 µg/g to 1.6 µg/g. The highest concentrations of BMAA were measured during summer when the highest picocyanobacteria abundances were recorded. CONCLUSIONS: While it is not possible to ascertain a direct link between shellfish consumption and the existence of this ALS cluster, these results add new data to the potential association of BMAA with sporadic amyotrophic lateral sclerosis, one of the most severe neurodegenerative disorder.

  19. Dietary exposure to an environmental toxin triggers neurofibrillary tangles and amyloid deposits in the brain.

    Cox, Paul Alan; Davis, David A; Mash, Deborah C; Metcalf, James S; Banack, Sandra Anne

    2016-01-27

    Neurofibrillary tangles (NFT) and β-amyloid plaques are the neurological hallmarks of both Alzheimer's disease and an unusual paralytic illness suffered by Chamorro villagers on the Pacific island of Guam. Many Chamorros with the disease suffer dementia, and in some villages one-quarter of the adults perished from the disease. Like Alzheimer's, the causal factors of Guamanian amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC) are poorly understood. In replicated experiments, we found that chronic dietary exposure to a cyanobacterial toxin present in the traditional Chamorro diet, β-N-methylamino-l-alanine (BMAA), triggers the formation of both NFT and β-amyloid deposits similar in structure and density to those found in brain tissues of Chamorros who died with ALS/PDC. Vervets (Chlorocebus sabaeus) fed for 140 days with BMAA-dosed fruit developed NFT and sparse β-amyloid deposits in the brain. Co-administration of the dietary amino acid l-serine with l-BMAA significantly reduced the density of NFT. These findings indicate that while chronic exposure to the environmental toxin BMAA can trigger neurodegeneration in vulnerable individuals, increasing the amount of l-serine in the diet can reduce the risk. PMID:26791617

  20. Effects of Dietary Exposure to Zearalenone (ZEN on Carp (Cyprinus carpio L.

    Constanze Pietsch

    2015-08-01

    Full Text Available The mycotoxin zearalenone (ZEN is frequently contaminating animal feeds including feed used in aquaculture. In the present study, the effects of dietary exposure to ZEN on carp (Cyprinus carpio L. were investigated. ZEN at three different concentrations (low dose: 332 µg kg−1, medium dose: 621 µg kg−1 and high dose: 797 µg kg−1 final feed, respectively was administered to juvenile carp for four weeks. Additional groups received the mycotoxin for the same time period but were fed with the uncontaminated diet for two more weeks to examine the reversibility of the ZEN effects. No effects on growth were observed during the feeding trial, but effects on haematological parameters occurred. In addition, an influence on white blood cell counts was noted whereby granulocytes and monocytes were affected in fish treated with the medium and high dose ZEN diet. In muscle samples, marginal ZEN and α-zearalenol (α-ZEL concentrations were detected. Furthermore, the genotoxic potential of ZEN was confirmed by analysing formation of micronuclei in erythrocytes. In contrast to previous reports on other fish species, estrogenic effects measured as vitellogenin concentrations in serum samples were not increased by dietary exposure to ZEN. This is probably due to the fact that ZEN is rapidly metabolized in carp.

  1. Hormone Use in Food Animal Production: Assessing Potential Dietary Exposures and Breast Cancer Risk.

    Nachman, Keeve E; Smith, Tyler J S

    2015-03-01

    In recent years, increasing attention has been paid to the role of hormones in breast cancer etiology, following reports that heightened levels of endogenous hormones and exposure to exogenous hormones and other endocrine-disrupting chemicals through food and the environment are associated with increased breast cancer risk. Seven hormone drugs (testosterone propionate, trenbolone acetate, estradiol, zeranol, progesterone, melengestrol acetate, and bovine somatotropin) are approved by the U.S. Food and Drug Administration for use in food animals. There is concern that these drugs or their biologically active metabolites may accumulate in edible tissues, potentially increasing the risk of exposure for consumers. To date, the potential for human exposure to residues of these compounds in animal products, as well as the risks that may result from this exposure, is poorly understood. In this paper, we discuss the existing scientific evidence examining the toxicological significance of exposure to hormones used in food animal production in relation to breast cancer risk. Through a discussion of U.S. federal regulatory programs and the primary literature, we interpret the state of surveillance for residues of hormone drugs in animal products and discuss trends in meat consumption in relation to the potential for hormone exposure. Given the lack of chronic bioassays of oral toxicity of the seven hormone compounds in the public literature and the limitations of existing residue surveillance programs, it is not currently possible to provide a quantitative characterization of risks that result from the use of hormonal drugs in food animal production, complicating our understanding of the role of dietary hormone exposure in the population burden of breast cancer. PMID:26231238

  2. Accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.) following dietary exposure

    Methylmercury is known to bioaccumulate and biomagnify up the marine food chain. Fish from high levels of the marine food chain may contain relatively high concentrations of mercury, and most (>70%) of the mercury found in muscle is methylmercury. In aquaculture, marine protein (mainly fishmeal) is the dominant source of methylmercury, and this raises some concern with regards to fish welfare and consumer safety. A dietary exposure study, including a depuration period, was carried out in order to study the accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.), and to estimate the transfer of methylmercury from feed to fish. Fish were sampled throughout a three month exposure period and a three month depuration period. Muscle samples were fractionated into a protein and a lipid fraction by lipid extraction using methanol and chloroform. Mercury and methylmercury were determined by inductively coupled plasma mass spectrometry (ICPMS) and gas chromatography-inductively coupled plasma mass spectrometry (GC-ICPMS), respectively. A continuous accumulation of methylmercury, after a lag period of 10 days, was observed in muscle tissue during the three months exposure to methylmercury (0.95+/-0.03μg Hg/g feed, n=6). After three months, the final concentration in muscle was 0.38+/-0.04μg Hg/gww (n=6), where methylmercury constituted 90-95% of the mercury present. The elimination of methylmercury from muscle was slow and incomplete (within the three months of depuration) with an estimated elimination half-life (t1/2) of 377 days. The transfer of methylmercury from feed to Atlantic cod, described by the estimated absorption efficiency, was 38%. In muscle more than 99% of the mercury was found in the protein fraction. These results suggest that Atlantic cod readily takes up dietary methylmercury, which is efficiently accumulated into muscle, where it is incorporated into larger peptides or proteins. Comparable results were found for Atlantic salmon

  3. Assessing dietary exposure to cadmium in a metal recycling community in Vietnam: Age and gender aspects

    Minh, Ngo Duc [Vietnamese Academy of Agriculture Sciences, Soils and Fertilizers Research Institute (SFRI), Tu Liem, Hanoi (Viet Nam); Hough, Rupert Lloyd, E-mail: rupert.hough@hutton.ac.uk [The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH (United Kingdom); Thuy, Le Thi [Vietnamese Academy of Agriculture Science, Institute of Agricultural Environment (IAE), Tu Liem, Hanoi (Viet Nam); Nyberg, Ylva [Department of Crop Production Ecology, PO Box 7043, Swedish University of Agricultural Sciences (SLU), SE-750 07 Uppsala (Sweden); Mai, Le Bach [National Institute of Nutrition, 48b Tang Bat Ho, Hoan Kiem, Hanoi (Viet Nam); Vinh, Nguyen Cong [Vietnamese Academy of Agriculture Sciences, Soils and Fertilizers Research Institute (SFRI), Tu Liem, Hanoi (Viet Nam); Khai, Nguyen Manh [Faculty of Environmental Sciences, Ha Noi University of Science (HUS-VNU), 334 Nguyen Trai, Thanh Xuan, Ha Noi (Viet Nam); Oeborn, Ingrid [Department of Crop Production Ecology, PO Box 7043, Swedish University of Agricultural Sciences (SLU), SE-750 07 Uppsala (Sweden)

    2012-02-01

    This study estimates the dietary exposure to cadmium (Cd), and associated potential health risks, for individuals living and working in a metal recycling community (n = 132) in Vietnam in comparison to an agricultural (reference) community (n = 130). Individual-level exposure to Cd was estimated through analysis of staple foodstuffs combined with information from a food frequency questionnaire. Individual-level exposure estimates were compared with published 'safe' doses to derive a Hazard Quotient (HQ) for each member of the study population. Looking at the populations as a whole, there were no significant differences in the diets of the two villages. However, significantly more rice was consumed by working age adults (18-60 years) in the recycling village compared to the reference village (p < 0.001). Rice was the main staple food with individuals consuming 461 {+-} 162 g/d, followed by water spinach (103 {+-} 51 kg/d). Concentrations of Cd in the studied foodstuffs were elevated in the metal recycling village. Values of HQ exceeded unity for 87% of adult participants of the metal recycling community (39% had a HQ > 3), while 20% of adult participants from the reference village had an HQ > 1. We found an elevated health risk from dietary exposure to Cd in the metal recycling village compared to the reference community. WHO standard of 0.4 mg Cd/kg rice may not be protective where people consume large amounts of rice/have relatively low body weight. - Highlights: Black-Right-Pointing-Pointer First individual-level risk assessment of cadmium in recycling villages of Vietnam. Black-Right-Pointing-Pointer Dietary analysis undertaken for a recycling community and an agricultural community. Black-Right-Pointing-Pointer No significant differences were found between the diets of the two populations. Black-Right-Pointing-Pointer 87% of people in the recycling community had elevated health risk. Black-Right-Pointing-Pointer WHO standard (0.4 mg Cd/kg rice) may

  4. The effect of dietary vitamin A on NO2 exposure on the hamster lung

    The effect of dietary vitamin A and NO2 exposure on the hamster lung was evaluated by histopathology, electron microscopy, and thymidine uptake studies. Hamsters were maintained on deficient (0 micrograms), adequate (100 micrograms), and high (200 micrograms) dose levels of vitamin A while being exposed repeatedly to 10 ppm of NO2 for 5 hours once a week over an 8-week period. Hamsters of the deficient group exhibited clinical and morphologic changes characteristic of vitamin A deficiency. Animals maintained on adequate and high dose levels of vitamin A were not affected by vitamin A deficiency. Hypertrophy and hyperplasia of the epithelial cells of the terminal bronchiolar alveolar region of lungs of adequately and highly dosed animals were greater than those observed in the deficient animals, when NO2 exposure was given. However, the extent of the lesions observed in all three groups was less than that seen in normal hamsters given a single, 5-hour NO2 exposure. Ultrastructural changes observed in vitamin A-deficient hamsters exposed to NO2 were hypertrophy and hyperplasia of bronchiolar epithelial cells, diffuse loss of cilia, membrane damage, and mitochondrial damage manifested by calcium deposition. Tritiated thymidine uptake studies of lungs of animals exposed repeatedly revealed a rather erratic cell renewal pattern following NO2 exposure in comparison to the group of animals exposed singly

  5. Dietary antioxidants and the biochemical response to oxidant inhalation. II. Influence of dietary selenium on the biochemical effects of ozone exposure in mouse lung

    Elsayed, N.M.; Hacker, A.D.; Kuehn, K.; Mustafa, M.G.; Schrauzer, G.N.

    1983-12-01

    The influence of dietary selenium (Se) on the pulmonary biochemical response to ozone (O/sub 3/) exposure was examined. For 11 weeks, weanling female strain A/St mice were fed a test diet containing Se either at 0 ppm (-Se) or 1 ppm (+Se). Each diet contained 55 ppm vitamin E (vit E). Mice from each dietary group were exposed to 0.8 +/- 0.05 ppm (1568 +/- 98 micrograms/m3) O/sub 3/ continuously for 5 days. After O/sub 3/ exposure, they were killed along with a matched number of unexposed controls, and their lungs were analyzed for various biochemical parameters. The Se contents of lung tissue and whole blood were determined, and the levels were seven- to eightfold higher in +Se mice than in -Se mice, reflecting the Se intake of the animals. In unexposed control mice, Se deficiency caused a decline in glutathione peroxidase (GP) activity relative to +Se group. After O/sub 3/ exposure, the GP activity in the -Se group was associated with a lack of stimulation of glutathione reductase (GR) activity and the pentose phosphate cycle (PPC) as assessed by measuring glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities. In contrast, the +Se group after O/sub 3/ exposure exhibited increases in all four enzyme activities. Other parameters, e.g., lung weight, total lung protein, DNA and nonprotein sulfhydryl contents, and O/sub 2/ consumption, were not affected by dietary Se in the presence or absence of O/sub 3/ exposure. The data indicate that dietary Se alters the GP activity, which in turn influences the GR and PPC activities in the lung evidently through a reduced demand for NADPH. The level of vit E in the lung was found to be twofold higher in the -Se group than in the +Se group, suggesting a compensatory relationship between Se and vit E in the lung. With O3 exposure, both Se and vit E contents further increased in the lungs of each dietary group.

  6. Dietary acrylamide exposure in male F344 rats: Dataset of systemic oxidative stress and inflammation markers.

    Jin, Xiaolei; Coughlan, Melanie; Roberts, Jennifer; Mehta, Rekha; Raju, Jayadev

    2016-06-01

    We previously reported that dietary acrylamide, at doses (10 and 50 mg/kg diet) known to cause rodent tumors, lowered serum total high density lipoprotein and total testosterone, increased serum lipase, and lowered lymphocytes levels together with other hematological parameters in male F344 rats exposed for 10 weeks (doi: 10.1016/j.etap.2014.11.009 [1]). Here we present data related to the role of food-borne acrylamide exposure (at 0, 5, 10 and 50 mg/kg diet) in the presence of low (7% wt/wt) or high (23.9% wt/wt) dietary fat on serum and urinary markers of oxidative stress and inflammation in F344 rats. Briefly, urine and serum samples were collected from the experimental animals a day prior to or at the time of necropsy, respectively and processed for enzyme-linked immunosorbent assay estimations of biochemical markers. Urine samples were analyzed for 8-hydroxydeoxyguanosine and isoprostane, and serum samples for total antioxidant capacity, paraoxonase 1 activity, c-reactive protein, homocysteine, oxidized low-density lipoprotein, intercellular adhesion molecule-1, thromboxin 2, and Nε-(carboxymethyl)lysine. PMID:27014731

  7. Dietary PCDD/PCDF exposure estimates for the U.S. population

    South, P.; S. Kathleen Egan; Troxell, T.; P. Michael Bolger [U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park (United States)

    2004-09-15

    Dioxin-like compounds (DLCs) are a group of environmental contaminants whose primary route of human exposure occurs via the consumption of fatty foods of animal origin. Since the mid-1990s, the U.S. Food and Drug Administration (FDA) has tested specific foods with the goal of describing and reducing DLC exposure. In 1999, FDA's dioxin monitoring program began analyzing foods collected under its Total Diet Study (TDS). Conducted annually since 1961, the TDS is FDA's ongoing market basket survey designed to monitor the U.S. food supply for levels of toxic chemical contaminants (pesticide residues, industrial chemicals and toxic elements) and nutritional elements. This paper reports on dietary exposure estimates for DLCs, specifically polychlorinated dibenzo-pdioxin (PCDD) and polychlorinated dibenzofuran (PCDF), calculated from results of PCDD/PCDF analyses of TDS samples from 2001 and 2002 and food consumption data collected in USDA's 1994-96, 1998 Continuing Survey of Food Intakes by Individuals (CSFII).

  8. Effects of dietary exposure of polycyclic musk HHCB on the metamorphosis of Xenopus laevis.

    Pablos, María Victoria; Jiménez, María Ángeles; San Segundo, Laura; Martini, Federica; Beltrán, Eulalia; Fernández, Carlos

    2016-06-01

    The compound 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-[γ]-2-benzopyrane (HHCB; galaxolide, Chemical Abstracts Service number 1222-05-5) is a synthetic musk used extensively as a fragrance in many consumer products and classified as an emerging pollutant. The ecotoxicological information available for HHCB addresses exposure via water, but this compound is frequently adsorbed into particulate matter. The goal of the present study was to assess the effects of dietary exposure to several environmentally relevant HHCB concentrations adsorbed in food during Xenopus laevis metamorphosis. The authors sought to determine if such exposure to this synthetic musk resulted in histological changes in the thyroid gland in conjunction with changes in development (staging, timing to metamorphosis), body weight, and length. Developmental acceleration on day 14, together with hypertrophy of the thyroid follicular epithelium in tadpoles, suggested a possible agonistic effect of HHCB, which would have been compensated after metamorphosis by regulatory mechanisms to maintain homeostasis. Further research into the potential thyroid-related mechanisms of action of HHCB should be conducted. Environ Toxicol Chem 2016;35:1428-1435. © 2015 SETAC. PMID:26472276

  9. DEVELOPMENT OF ARSENIC SPECIATION METHODOLOGY FOR DETERMINING BACKGROUND EXPOSURE LEVELS OF INORGANIC ARSENIC IN DIETARY SAMPLES AND APPLICATION TO IN VITRO BIOACCESSIBILITY STUDIES

    Ingestion of arsenic is the primary route of exposure for most people, with dietary intake and drinking water as the primary sources of that exposure. Traditionally, measurements of arsenic dietary intake are based on food consumption data coupled with total arsenic data from a ...

  10. Design, development and validation of software for modelling dietary exposure to food chemicals and nutrients.

    McNamara, C; Naddy, B; Rohan, D; Sexton, J

    2003-10-01

    The Monte Carlo computational system for stochastic modelling of dietary exposure to food chemicals and nutrients is presented. This system was developed through a European Commission-funded research project. It is accessible as a Web-based application service. The system allows and supports very significant complexity in the data sets used as the model input, but provides a simple, general purpose, linear kernel for model evaluation. Specific features of the system include the ability to enter (arbitrarily) complex mathematical or probabilistic expressions at each and every input data field, automatic bootstrapping on subjects and on subject food intake diaries, and custom kernels to apply brand information such as market share and loyalty to the calculation of food and chemical intake. PMID:14555354

  11. Acute Dietary Nitrate Supplementation and Exercise Performance in COPD: A Double-Blind, Placebo-Controlled, Randomised Controlled Pilot Study

    Curtis, Katrina J.; O'Brien, Katie A; Tanner, Rebecca J; Polkey, Juliet I.; Minnion, Magdalena; Feelisch, Martin; Polkey, Michael I; Edwards, Lindsay M.; Hopkinson, Nicholas S

    2015-01-01

    Background: Dietary nitrate supplementation can enhance exercise performance in healthy people, but it is not clear if it is beneficial in COPD. We investigated the hypotheses that acute nitrate dosing would improve exercise performance and reduce the oxygen cost of submaximal exercise in people with COPD. Methods: We performed a double-blind, placebo-controlled, cross-over single dose study. Subjects were randomised to consume either nitrate-rich beetroot juice (containing 12.9mmoles nit...

  12. Acute Exposure from RADON-222 and Aerosols in Drinking Water

    Bernhardt, George Paul, IV

    Radon-222 in water is released when the water is aerated, such as during showering. As a result, a temporary burst of radon-222 can appear as a short term, or acute, exposure. This study looked at homes with radon-222 concentrations in water from 800 picocuries per liter (pCi/l) to 53,000 pCi/l to determine the buildup of radon gas in a bathroom during showering. Samples from the tap and drain, compared to determine the percentage of radon-222 released, showed that between 58% and 88% of radon-222 in the water was released. The resultant radon-222 increase in air, measured with a flow-through detector, ranged from 2 pCi/l to 114 pCi/l in bathrooms due to a 10 to 15 minute shower with water flow rates ranging from 3 l/min to 6 l/min. Significantly, these rates did not fall rapidly but stayed approximately the same for up to 15 minutes after the water flow ceased. In examining exposures, the true danger is in the radon-222 progeny rather than the radon itself. The progeny can be inhaled and deposited in the tracheobronchial passages in the lung. Filter samples of bathroom air measured in a portable alpha spectrometer showed an increase in radon-222 progeny, notably polonium-218 and -214, in the air after showering. These increases were gradual and were on the order of 0.5 pCi/l at the highest level. Tap samples measured in a portable liquid scintillator showed that the progeny are present in the water but are not in true secular equilibrium with the radon-222 in the water. Therefore, the radon-222 does not have to decay to produce progeny since the progeny are already present in the water. A two stage sampler was used to examine the percentage of radiation available in aerosols smaller than 7 microns. Repeated trials showed that up to 85% of the radiation available in the aerosols is contained in the smaller, more respirable particles.

  13. Effect of Acute Dietary Nitrate Consumption on Oxygen Consumption During Submaximal Exercise in Hypobaric Hypoxia.

    Carriker, Colin R; Mermier, Christine M; Van Dusseldorp, Trisha A; Johnson, Kelly E; Beltz, Nicholas M; Vaughan, Roger A; McCormick, James J; Cole, Nathan H; Witt, Christopher C; Gibson, Ann L

    2016-08-01

    Reduced partial pressure of oxygen impairs exercise performance at altitude. Acute nitrate supplementation, at sea level, may reduce oxygen cost during submaximal exercise in hypobaric hypoxia. Therefore, we investigated the metabolic response during exercise at altitude following acute nitrate consumption. Ten well-trained (61.0 ± 7.4 ml/kg/min) males (age 28 ± 7 yr) completed 3 experimental trials (T1, T2, T3). T1 included baseline demographics, a maximal aerobic capacity test (VO2max) and five submaximal intensity cycling determination bouts at an elevation of 1600 m. A 4-day dietary washout, minimizing consumption of nitrate-rich foods, preceded T2 and T3. In a randomized, double-blind, placebo-controlled, crossover fashion, subjects consumed either a nitrate-depleted beetroot juice (PL) or ~12.8 mmol nitrate rich (NR) beverage 2.5 hr before T2 and T3. Exercise at 3500 m (T2 and T3) via hypobaric hypoxia consisted of a 5-min warm-up (25% of normobaric VO2max) and four 5-min cycling bouts (40, 50, 60, 70% of normobaric VO2max) each separated by a 4-min rest period. Cycling RPM and watts for each submaximal bout during T2 and T3 were determined during T1. Preexercise plasma nitrite was elevated following NR consumption compared with PL (1.4 ± 1.2 and 0.7 ± 0.3 uM respectively; p exercise at 3500 m does not reduce oxygen cost but may reduce blood lactate accumulation at lower intensity workloads. PMID:26630309

  14. Hexabromocyclododecane (HBCD) in the Korean food basket and estimation of dietary exposure.

    Barghi, Mandana; Shin, Eun-Su; Son, Min-Hui; Choi, Sung-Deuk; Pyo, Heesoo; Chang, Yoon-Seok

    2016-06-01

    1,2,5,6,9,10-hexabromocyclododecane (HBCD) is a brominated flame retardant that is used worldwide in expanded and extruded polystyrene foam and simultaneously emitted to the environment. HBCD can easily accumulate in animals and humans and cause neurotoxicity, thyroid hormone disruption, and reproductive disorders. Therefore, it is essential to monitor the HBCD concentrations in foods and estimate the human exposure through the diet. In this study a total of 521 food samples from eight food categories were sampled and analyzed for their HBCD content. Based on consumption data, the average dietary intake of the general Korean population and specific subgroups was calculated. The highest levels of HBCD were found in fish and shellfish (0.47 ng g(-1) ww), and this was attributed to natural exposure to the contaminated marine environments and the HBCD bioaccumulation. In addition, the use of expanded polystyrene buoys in aquaculture was also found to be a potential source of HBCD in bivalves. The high solubility of α-HBCD in water and the persistence of this diastereomer compared to β- and γ-HBCD in biological tissues, led to higher accumulation of α-HBCD in animal-based foods. In contrast, the diastereomeric selectivity and lower metabolic capacity in plants compared with animals led to the predominance of γ-HBCD in plant-based foods. The dietary intake of HBCD was estimated to be 0.82 ng kg(-1) bw d(-1) in the general population and 2.89 ng kg(-1) bw d(-1) in children up to 5 years of age. The high HBCD intake in children was found to be a result of their lower body weight and their high consumption of milk and homemade Korean baby foods that usually contain fish. PMID:26924755

  15. Steroids in marine aquaculture farms surrounding Hailing Island, South China: occurrence, bioconcentration, and human dietary exposure.

    Liu, Shan; Chen, Hui; Xu, Xiang-Rong; Liu, Shuang-Shuang; Sun, Kai-Feng; Zhao, Jian-Liang; Ying, Guang-Guo

    2015-01-01

    The occurrence, bioconcentration, and human dietary exposure via seafood consumption of 24 steroids were investigated by rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS) in six typical marine aquaculture farms surrounding Hailing Island, South China. Ten, 9, 10, 15 of 24 steroids were detected at concentrations ranging from testosterone) to 40 ng/L (prednisolone), from 0.1 (4-androstene-3,17-dione) to 2.4 ng/g (progesterone), from 0.3 ng/g (testosterone) to 21.4 ng/g (epi-androsterone), and from testosterone) to 560 ng/g (cortisol) (wet weight) in the water, sediment, feed and biota samples, respectively. Synthetic steroids (androsta-1,4-diene-3,17-dione, 17α-boldenone, 17β-boldenone, 17β-trenbolone, prednisolone, norgestrel) were detected in the feed samples, clearly demonstrating the illegal use of steroids in the feed. The field bioconcentration factors (BCFs) of steroids calculated in different aquatic organisms ranged from 93.8 to 4000. The estimated daily intakes (EDIs) of androgens, glucocorticoids, and progestagens via consumption of seafood (i.e., shrimps, crabs, mollusks, and fish) for different age groups were in the range of 33.4-134, 2061-8566, and 40.4-155 ng/d for children (2-5 years), youth (6-18 years), and adults (>18 years), respectively. Even though no significant risk from dietary exposure arises from individual steroid, elevated risk to humans can result from the occurrence of multiple steroids in the seafood raised in the aquaculture farms, especially for the sensitive populations, such as pregnant women and children. PMID:25268569

  16. Dietary exposure to persistent organic pollutants and metals among Inuit and Chukchi in Russian Arctic Chukotka

    Alexey A. Dudarev

    2012-07-01

    Full Text Available Objectives. The general aim was to assess dietary exposure to selected persistent organic pollutants (POPs and metals among Eskimo (Inuit and Chukchi of the Chukotka Peninsula of the Russian Arctic, and to establish recommendations for exposure risk reduction. Study design. A cross-sectional evaluation of nutritional patterns of coastal and inland indigenous peoples of the Chukotka Autonomous Okrug (in 2001–2003; assessment of the levels of persistent toxic substances (PTSs in traditional foods and their comparison to Russian food safety limits; the identification of local sources of food contamination; and the recommendation and implementation of risk management measures. Methods. Community-based dietary survey of self reported food frequencies (453 persons, chemical analyses (POPs and metals of local foods and indoor matters (397 samples, substantiation of recommendations for daily (weekly, monthly intakes of traditional food. Results. POPs in traditional food items are generally below the Russian food safety limits except marine mammal fat, while Hg and Cd are high mainly in mammal viscera. Lead is relatively low in tissues of all animals studied. For the Chukotka coastal communities, seals constitute the principal source of the whole suite of PTSs considered. Consumption restrictions are recommended for marine and freshwater fish, some wild meats (waterfowl and seal, fats (whale and seal, liver (most animals and kidney (reindeer, walrus and seal. Evidence is presented that contamination of foodstuffs may be significantly increased during storing/processing/cooking of food due to indoor and outdoor environmental conditions. Conclusions. Based on the analytical findings and the local PTSs sources identified, guidelines on food safety are suggested, as well as measures to reduce food contamination and domestic and local sources. Important and urgent remedial actions are recommended to minimize PTSs environmental and domestic contamination

  17. Long term exposure to ambient air pollution and incidence of acute coronary events

    Cesaroni, Giulia; Forastiere, Francesco; Stafoggia, Massimo;

    2014-01-01

    To study the effect of long term exposure to airborne pollutants on the incidence of acute coronary events in 11 cohorts participating in the European Study of Cohorts for Air Pollution Effects (ESCAPE)....

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

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

  19. Dietary predictors of young children’s exposures to chlorpyrifos, permethrin, and 2,4-D using urinary biomonitoring

    Few data exist on the association between dietary habits and urinary biomarker concentrations of pesticides in children. The objective was to examined the association between the weekly intake frequency of 65 food items and urinary biomarkers of exposure to chlorpyrifos (3,5,6-tr...

  20. Continuous positive airway pressure increases haemoglobin O2 saturation after acute but not prolonged altitude exposure.

    p. Agostoni, Caldara G, Bussotti M, Revera M, Valentini M, Gregorini F, Faini A, Lombardi C, Bilo G, Giuliano A, Veglia F, Savia G, P.A. Modesti, Mancia G, Parati G

    2010-01-01

    Abstract: It is unknown whether subclinical high-altitude pulmonary oedema reduces spontaneously after prolonged altitude exposure. Continuous positive airway pressure (CPAP) removes extravascular lung fluids and improves haemoglobin oxygen saturation in acute cardiogenic oedema. We evaluated the presence of pulmonary extravascular fluid increase by assessing CPAP effects on haemoglobin oxygen saturation under acute and prolonged altitude exposure. We applied 7 cm H2O CPAP for 30 min to he...

  1. Brewing complications: the effect of acute ethanol exposure on wound healing

    Radek, Katherine A.; Ranzer, Matthew J.; DiPietro, Luisa A.

    2009-01-01

    Ethanol consumption is linked to a higher incidence of traumatic wounds and increases the risk for morbidity and mortality following surgical or traumatic injury. One of the most profound effects of acute ethanol exposure on wound healing occurs during the inflammatory response, and altered cytokine production is a primary component. Acute ethanol exposure also impairs the proliferative response during healing, causing delays in epithelial coverage, collagen synthesis, and blood vessel regrow...

  2. Acute leukaemia after exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid.

    Timonen, T T; Palva, I P

    1980-01-01

    Acute leukaemia is known to develop in many cases of benzene-induced pancytopenia [1]. This is a report of the development of acute leukaemia in a patient who had apparently recovered from pancytopenia after chronic exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid. PMID:6769284

  3. Energetic cost of dietary exposure to polychlorinated biphenyls (PCBS) for white-footed mice, Peromyscus leucopus

    Voltura, M.B.; French, J.B.

    1998-01-01

    Contaminant exposure is an environmental factor often overlooked in ecological studies. Yet exposure to toxicants is likely to be metabolically expensive, and result in a trade-off between energy spent to detoxify an excrete contaminants, and energy allocated to growth or reproduction. To quantify the energetic cost of PCB exposure, we fed mice diets containing 0, 0.1, 10 and 25 ppm PCBs (mg PCBs/kg food). After 6 wks, there were no differences in food intake or body mass related to the level of dietary PCBs. We continued to feed mice the PCB diets for one year, and then measured food intake and resting metabolic rate. After one year, all mice had gained mass, but mice on the 25 ppm diet were significantly heavier than mice in the other groups. Mice on the 25 ppm diet also showed an increase in both food intake (p=0.06) and metabolic rate (p=0.01), after correction for differences in body mass. Food intake averaged 4.1 g/d for mice on the 25 ppm diet, compared to 3.7 gld for control mice. Oxygen consumption at 30°C averaged 40.1 ml O2/h for mice on the 25 ppm diet, compared to 36.6 ml O2/h for control mice. These results show that for white-footed mice, there is an energetic cost to contaminant exposure that when combined with other environmental stresses, will influence patterns of energy acquisition and allocation.

  4. Dietary mercury exposure to endangered California Clapper Rails in San Francisco Bay

    Casazza, Michael L.; Ricca, Mark A.; Overton, Cory T.; Takekawa, John Y.; Merritt, Angela M.; Ackerman, Joshua T.

    2015-01-01

    California Clapper Rails (Rallus longirostris obsoletus) are an endangered waterbird that forage in tidal-marsh habitats that pose risks from mercury exposure. We analyzed total mercury (Hg) in six macro-invertebrate and one fish species representing Clapper Rail diets from four tidal-marshes in San Francisco Bay, California. Mercury concentrations among individual taxa ranged from lowest at Colma Creek (mean range: 0.09–0.2 μg/g dw) to highest at Cogswell (0.2–0.7), Laumeister (0.2–0.9) and Arrowhead Marshes (0.3–1.9). These spatial patterns for Hg matched patterns reported previously in Clapper Rail blood from the same four marshes. Over 25% of eastern mudsnails (Ilyanassa obsolete) and staghorn sculpin (Leptocottus armatus) exceeded dietary Hg concentrations (ww) often associated with avian reproductive impairment. Our results indicate that Hg concentrations vary considerably among tidal-marshes and diet taxa, and Hg concentrations of prey may provide an appropriate proxy for relative exposure risk for Clapper Rails.

  5. A novel approach reveals that zinc oxide nanoparticles are bioavailable and toxic after dietary exposures.

    Croteau, Marie-Noële; Dybowska, Agnieszka D; Luoma, Samuel N; Valsami-Jones, Eugenia

    2011-03-01

    If engineered nanomaterials are released into the environment, some are likely to end up associated with the food of animals due to aggregation and sorption processes. However, few studies have considered dietary exposure of nanomaterials. Here we show that zinc (Zn) from isotopically modified (67)ZnO particles is efficiently assimilated by freshwater snails when ingested with food. The (67)Zn from nano-sized (67)ZnO appears as bioavailable as (67)Zn internalized by diatoms. Apparent agglomeration of the zinc oxide (ZnO) particles did not reduce bioavailability, nor preclude toxicity. In the diet, ZnO nanoparticles damage digestion: snails ate less, defecated less and inefficiently processed the ingested food when exposed to high concentrations of ZnO. It was not clear whether the toxicity was due to the high Zn dose achieved with nanoparticles or to the ZnO nanoparticles themselves. Further study of exposure from nanoparticles in food would greatly benefit assessment of ecological and human health risks. PMID:21417690

  6. A novel approach reveals that zinc oxide nanoparticles are bioavailable and toxic after dietary exposures

    Croteau, M.-N.; Dybowska, A.D.; Luoma, S.N.; Valsami-Jones, E.

    2011-01-01

    If engineered nanomaterials are released into the environment, some are likely to end up associated with the food of animals due to aggregation and sorption processes. However, few studies have considered dietary exposure of nanomaterials. Here we show that zinc (Zn) from isotopically modified 67ZnO particles is efficiently assimilated by freshwater snails when ingested with food. The 67Zn from nano-sized 67ZnO appears as bioavailable as 67Zn internalized by diatoms. Apparent agglomeration of the zinc oxide (ZnO) particles did not reduce bioavailability, nor preclude toxicity. In the diet, ZnO nanoparticles damage digestion: snails ate less, defecated less and inefficiently processed the ingested food when exposed to high concentrations of ZnO. It was not clear whether the toxicity was due to the high Zn dose achieved with nanoparticles or to the ZnO nanoparticles themselves. Further study of exposure from nanoparticles in food would greatly benefit assessment of ecological and human health risks. ?? 2011 Informa UK, Ltd.

  7. Modelling the effects of ionizing radiation on survival of animal population: acute versus chronic exposure.

    Kryshev, A I; Sazykina, T G

    2015-03-01

    The objective of the present paper was application of a model, which was originally developed to simulate chronic ionizing radiation effects in a generic isolated population, to the case of acute exposure, and comparison of the dynamic features of radiation effects on the population survival in cases of acute and chronic exposure. Two modes of exposure were considered: acute exposure (2-35 Gy) and chronic lifetime exposure with the same integrated dose. Calculations were made for a generic mice population; however, the model can be applied for other animals with proper selection of parameter values. In case of acute exposure, in the range 2-11 Gy, the population response was in two phases. During a first phase, there was a depletion in population survival; the second phase was a recovery period due to reparation of damage and biosynthesis of new biomass. Model predictions indicate that a generic mice population, living in ideal conditions, has the potential for recovery (within a mouse lifetime period) from acute exposure with dose up to 10-11 Gy, i.e., the population may recover from doses above an LD50 (6.2 Gy). Following acute doses above 14 Gy, however, the mice population went to extinction without recovery. In contrast, under chronic lifetime exposures (500 days), radiation had little effect on population survival up to integrated doses of 14-15 Gy, so the survival of a population subjected to chronic exposure was much better compared with that after an acute exposure with the same dose. Due to the effect of "wasted radiation", the integrated dose of chronic exposure could be about two times higher than acute dose, producing the same effect on survival. It is concluded that the developed generic population model including the repair of radiation damage can be applied both to acute and chronic modes of exposure; results of calculations for generic mice population are in qualitative agreement with published data on radiation effects in mice. PMID

  8. Cardiovascular Risk Factors in Normolipidemic Acute Myocardial Infarct Patients on Admission – Do Dietary Fruits and Vegetables Offer Any Benefits?

    Arun Kumar

    2010-10-01

    Full Text Available Background: Myocardial Infarction (MI is a leading cause of death in India. Whether dietary vitamins could reduce risk of cardiovascular disease among Indians is still not clear and very few studies have addressed the association between dietary vitamin acting as an antioxidant or pro-oxidant and its effect on risk reduction or aggravation in normolipidemic AMI patients. Objective: The goal of the current study was to address the association between dietary vitamin and cardiovascular risk in normolipidemic acute myocardial infarct patients compared with healthy controls. Design: Dietary intake of vitamins was assessed by 131 food frequency questionnaire items in both AMI patients and age/sex-matched controls. The associated changes in risk factors due to antioxidant vitamins intake was also assessed in normolipidemic acute myocardial patients and was compared with controls. Results: Dietary intake of vitamin A, B1, B2, B3 was significantly higher in AMI patients compared to healthy controls but the intake of vitamin C was significantly higher in controls compared to AMI patients. Even though the vitamins intake was higher in patients, the associated cardiovascular risk factors were not reduced compared to controls. The total cholesterol, LDL-c, TAG were significantly higher (p<0.001 in AMI patients except HDL-c which was significantly higher (p<0.001 in controls. The endogenous antioxidants were found to be significantly lowered in patients compared to controls in spite of higher vitamin intake. Similarly the enzymatic antioxidants were also significantly lowered in patients. The mean serum Lipoprotein (a malondialdehyde (MDA and conjugated diene (CD levels in patients were significantly elevated compared with controls. The levels of caeruloplasmin, C-reactive protein, fibrinogen, ischemia-modified albumin were significantly higher but arylesterase activities were lowered in patients. Conclusion: Diets rich in vegetables and fruits do not seem

  9. In vitro and in vivo models of acute alcohol exposure

    Angela Dolganiuc; Gyongyi Szabo

    2009-01-01

    Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse,and identifies their suitability for biomedical research.

  10. Statement on a refined dietary exposure assessment of erythritol (E 968) taking into account additional data provided

    EFSA Panel on Food Additives and Nutrient Sources added to food (ANS)

    2013-01-01

    Following a request by the European Commission, the Scientific Panel on Food Additives and Nutrient Sources added to Foods (ANS) carried out an assessment of the dietary exposure to erythritol and concluded on the safety of the proposed use in beverages at a maximum use level of 2.5 %, taking into account additional exposure data provided to the Panel. Anticipated exposure to erythritol from its use as food additive including soft-drinks containing a mean concentration of 2.5 % erythritol wou...

  11. Bioaccumulation of PCBs in Arctic seabirds: influence of dietary exposure and congener biotransformation

    Four seabird species and their prey (zooplankton or fish) were collected in the Barents Sea to determine how dietary exposure, cytochrome P450 (CYP) enzyme activities and sex influenced their hepatic PCB concentrations and accumulation patterns. Five males and five females from each seabird species (little auk (Alle alle), Bruennich's guillemot (Uria lomvia), black guillemot (Cepphus grylle) and black-legged kittiwake (Rissa tridactyla)) were analysed. PCB concentrations could not be explained directly by carbon source (δ13C) or trophic position (δ15N), but by a combination of dietary parameters (δ13C, δ15N, migratory pattern, age) and contaminant metabolism. Contrary to previous studies, the PCB pattern differed among seabirds, with a higher proportion of persistent congeners (% of PCB-153, RPCB-153) in black-legged kittiwake than in auks. The PCB pattern also differed among auks, with little auk as the most efficient biotransformer (highest RPCB-153 values of persistent congeners). Based on high RPCB-153 values, Bruennich's guillemot poorly metabolised ortho-meta-unsubstituted congeners, whereas black guillemot poorly metabolised meta-para unsubstituted congeners. Species-specific differences in PCB biotransformation were confirmed by metabolic indices, where PCB patterns in seabirds were adjusted for PCB pattern in prey. The relative contribution of ortho-meta-unsubstituted congeners to ΣPCBsdecreased with increasing EROD activity. There were no differences in PCB concentrations, PCB patterns or cytochrome P450 enzyme activities between males and females. CYP P450 activities (CYP1A- and CYP2B/3A-like: EROD and testosterone 6β-hydroxylation, respectively) were low and did not correlate with concentrations of non- or mono-ortho Cl-substituted PCBs (NO- and MO-PCBs), or with total toxic equivalent concentrations (TEQs) for dioxin-like effects of NO- and MO-PCBs. - Contaminant patterns is linked to phylogeny and species-specific differences in enzyme systems

  12. Calcium-dependent behavioural responses to acute copper exposure in Oncorhynchus mykiss

    Poulsen, S.B.; Svendsen, Jon Christian; Aarestrup, Kim;

    2014-01-01

    Using rainbow trout Oncorhynchus mykiss, the present study demonstrated that: (1) calcium (Ca) increased the range of copper (Cu) concentrations that O. mykiss avoided; (2) Ca conserved the maintenance of pre-exposure swimming activity during inescapable acute (10 min) Cu exposure. Data showed th...

  13. Oxidative stress and immunologic responses following a dietary exposure to PAHs in Mya arenaria

    Gauthier-Clerc Sophie

    2008-12-01

    Full Text Available Abstract Background The aim of this research was to investigate oxidative stress and immune responses following a dietary polycyclic aromatic hydrocarbon (PAH exposure in a marine bioindicator organism, the soft shell clam, Mya arenaria. Immune parameters in hemolymph (haemocyte number, efficiency of phagocytosis and haemocyte activity and assessment of oxidative stress using catalase (CAT activity and levels of malondialdehyde (MDA performed on the digestive gland were estimated as biomarkers in clams fed in mesocosm with PAH contaminated phytoplankton. MDA levels and CAT activities were also measured in situ in organisms sampled in a control site (Metis Beach, Québec, Canada as well as organisms sampled in a site receiving domestic effluents (Pointe-au-Père, Québec, Canada, to assess effects of abiotic variables related to seasonal variations and mixed contamination on the selected parameters. Results Results on immune parameters suggest that the PAHs may interfere with the maturation and/or differentiation processes of haemocytes. MDA results showed that lipid peroxidation did not occur following the exposure. The levels of CAT activity corresponded to weak antioxidant activity (no significant differences. Recovery was noted for all the immune endpoints at the end of the experiment. Conclusion Results suggest that immune parameters are early biomarkers that can efficiently detect a physiological change during a short term exposure to low concentrations of PAHs. The in situ survey (in the natural environment suggested that clams from the Pointe-au-Père site did not show any oxidative stress as well as the clams contaminated in mesocosm, probably due to the low concentrations of PAHs used for this study. MDA levels increased however in organisms from Metis Beach, a response probably related to domestic effluents or parasitism.

  14. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    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

  15. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    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

  16. Dose related acute irritant symptom responses to occupational exposure to sodium borate dusts.

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

    1992-01-01

    A repeated measurement design was employed in the study of acute symptoms of eye and respiratory tract irritation resulting from occupational exposure to sodium borate dusts. The symptom assessment of the 79 exposed and 27 unexposed subjects comprised interviews before the shift began and then at regular hourly intervals for the next six hours of the shift, four days in a row. Exposures were monitored concurrently with a personal real time aerosol monitor. Two different exposure profiles, a d...

  17. Dietary exposure to cadmium, lead and nickel among students from the south-east region of Poland

    Zbigniew Marzec

    2014-11-01

    Full Text Available Dietary intake of cadmium, lead and nickel was determined among students from three universities in Lublin to assess the levels of exposure to these contaminants compared to PTWI and TDI values. The study was performed in 2006–2010 and involved 850 daily food rations of students from the south–east region of Poland. The technique of 24-hour dietary recall and diet duplicates was used. Cadmium, lead and nickel complexes with ammonium-pyrrolidindithiocarbamate were formed and extracted to the organic phase with 4-methylpentan-2-one – MIBK in which their content was measured by flame atomic absorption spectrometry. The highest intake of the elements studied was observed in 2008. The data show that in none of the cases, the level of intake reached 70 % of PTWI/TDI values and thus the risk of developing diseases related to high exposure to these toxic metals absorbed from foodstuffs was low. The parameters of methods were checked during determinations by adding standard solutions to the samples before mineralization and by using two reference materials: Total diet ARC/CL HDP and Bovine muscle RM NIST 8414. The dietary exposure to lead and cadmium has significantly decreased in recent years whereas the exposures to nickel remain on stable levels.

  18. Patterns of gene expression in carp liver after exposure to a mixture of waterborne and dietary cadmium using a custom-made microarray

    Gene expression changes in carp liver tissue were studied after acute (3 and 24 h) and subchronic (7 and 28 days) exposure to a mixture of waterborne (9, 105 and 480 μg/l) and dietary (9.5, 122 and 144 μg/g) cadmium, using a custom-made microarray. Suppression subtractive hybridization-PCR (SSH-PCR) was applied to isolate a set of 643 liver genes, involved in multiple biological pathways, such as energy metabolism (e.g. glucokinase), immune response (e.g. complement C3) and stress and detoxification (e.g. cytochrome P450 2F2, glutathione-S-transferase pi). These genes were subsequently spotted on glass-slides for the construction of a custom-made microarray. Resulting microarray hybridizations indicated a highly dynamic response to cadmium exposure. At low exposure concentrations (9 μg/l through water and 9.5 μg/g dry weight through food) mostly energy-related genes (e.g. glucokinase, elastase) were influenced, while a general stress response was obvious through induction of several stress-related genes, including hemopexin and cytochrome P450 2F2, at high cadmium concentrations. In addition, fish exposed to the highest cadmium concentrations showed liver damage after 7 days of exposure, as measured by elevated alanine transaminase activity in plasma and increased liver water content (wet-to-dry weight ratio). Moreover, decreased hematocrit and growth were found at the end of the experiment. Altogether this study clearly demonstrated the importance of varying exposure conditions for the characterization of the molecular impact of cadmium and showed that microarray results can provide important information, required to unravel the molecular events and responses related to cadmium exposure

  19. Effects of soil and dietary exposures to Ag nanoparticles and AgNO3 in the terrestrial isopod Porcellionides pruinosus

    The effects of Ag-NPs and AgNO3 on the isopod Porcellionides pruinosus were determined upon soil and dietary exposures. Isopods avoided Ag in soil, with EC50 values of ∼16.0 and 14.0 mg Ag/kg for Ag-NPs and AgNO3, respectively. Feeding inhibition tests in soil showed EC50s for effects on consumption ratio of 127 and 56.7 mg Ag/kg, respectively. Although similar EC50s for effects on biomass were observed for nanoparticulate and ionic Ag (114 and 120 mg Ag/kg dry soil, respectively), at higher concentrations greater biomass loss was found for AgNO3. Upon dietary exposure, AgNO3 was more toxic, with EC50 for effects on biomass change being >1500 and 233 mg Ag/kg for Ag-NPs and AgNO3, respectively. The difference in toxicity between Ag-NPs and AgNO3 could not be explained from Ag body concentrations. This suggests that the relation between toxicity and bioavailability of Ag-NPs differs from that of ionic Ag in soils. - Highlights: • Avoidance response of isopods exposed to Ag-NPs and AgNO3 via soil was similar. • Soil exposure to both Ag forms affected food consumption and isopod biomass. • Isopod feeding activity was also affected upon dietary exposure to both Ag forms. • Overall, AgNO3 was more toxic than Ag-NPs for both soil and dietary exposures. • Avoidance response was the most sensitive endpoint for both Ag forms. - Ag-NPs and AgNO3 equally affected isopod avoidance behavior, while AgNO3 generally caused greater toxicity in the feeding inhibition tests

  20. Occupational exposure to solvents and acute myeloid leukemia

    Talibov, Madar; Lehtinen-Jacks, Susanna; Martinsen, Jan Ivar;

    2014-01-01

    660 controls matched by year of birth, sex, and country. Occupational records were linked with Nordic Occupational Cancer Study job exposure matrix (JEM) to estimate quantitative values for 26 occupational exposure factors. Hazard ratios (HR) with 95% confidence intervals (95% CI) were estimated by...... for an excess risk in the groups of workers exposed to toluene, trichloroethylene and ARHC....

  1. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    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...

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

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

    2007-01-01

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

  3. Dietary exposure to essential and potentially toxic elements for the population of Hanoi, Vietnam

    Marcussen, H.; Jensen, Bodil Hamborg; Petersen, Annette;

    2013-01-01

    need to build more knowledge so that authorities can give dietary recommendations. The aim of this study was to determine the total dietary intake of essential and potentially toxic elements and to assess the nutritional quality and food safety risks of the average Hanoi diet. 22 foods or food groups......Knowledge of the dietary intake of essential and toxic elements in fast-developing Southeast Asian countries such as Vietnam is limited. Iron and Zn deficiency in Asia is a well-known problem and is partly due to rice constituting a major part of the diet. Dietary habits are changing and there is a...... average Hanoi dietary intake of essential elements to required intakes shows that the Hanoi diet is sufficient in most elements. However, the diet may be insufficient in Ca, Cr, Fe, K and possibly Zn for which dietary diversification of biofortification might provide solutions....

  4. Acute phase proteins in cattle after exposure to complex stress

    Lomborg, S. R.; Nielsen, L. R.; Heegaard, Peter M. H.;

    2008-01-01

    Abstract Stressors such as weaning, mixing and transportation have been shown to lead to increased blood concentrations of acute phase proteins (APP), including serum amyloid A (SAA) and haptoglobin, in calves. This study was therefore undertaken to assess whether SAA and haptoglobin levels in bl...

  5. Commuters’ air pollution exposure and acute health effects

    Zuurbier, M.M.M.

    2011-01-01

    People spend a substantial proportion of their time in traffic. In Europe, the average daily time in traffic is one to one and a half hour. Because of high in-traffic exposures and because most of the journeys are made during rush hours, the one to one and a half hour in traffic contributes disproportionately to total daily exposure to traffic related air pollution. So far a limited number of studies compared particulate matter exposures of different groups of commuters. There is limited evid...

  6. Reliable estimation of dietary exposure to furan from coffee: An automatic vending machine as a case study

    Mesías, Marta; Morales, F. J.

    2014-01-01

    Worldwide Food Safety Agencies have classified furan as carcinogenic and cytotoxic due to its effects in animal studies, and it has been associated with harmful effects to human health. It has been pointed out that coffee consumption is the major contributor to dietary furan exposure for adults. However, furan is highly volatile and its losses due to volatilization in the cup during the time expend to consume the coffee brew should be taken into account for a realistic estimation of the level...

  7. Acute pulmonary alveolar proteinosis due to exposure to cotton dust

    Thind Gurcharan

    2009-01-01

    Secondary pulmonary alveolar proteinosis (PAP) is rare but may occur in association with malignancy, certain infections, and exposure to inorganic or organic dust and some toxic fumes. This case report describes the second recorded case of PAP due to exposure to cotton dust. A 24-year-old man developed PAP after working as a spinner for eight years without respiratory protection. He was admitted as an emergency patient with very severe dyspnea for four months and cough for several years. Ches...

  8. Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

    The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 μg kg-1 were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 μg kg-1) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic α-tocopherol content) remained unchanged. Branchial Na+, K+-ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na+, K+-ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 μg kg-1). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 μg kg-1

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

    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.

  10. Bioaccumulation of PCBs in Arctic seabirds: influence of dietary exposure and congener biotransformation

    Borga, Katrine [Norwegian Polar Institute, N-9296 Tromsoe (Norway)]. E-mail: katrine.borga@npolar.no; Wolkers, Hans [Norwegian Polar Institute, N-9296 Tromsoe (Norway); Skaare, Janneche U. [National Veterinary Institute, P.O. Box 8156 Dep., N-0033 Oslo (Norway); Norwegian School of Veterinary Science, P.O. Box 8146 Dep., N-0033 Oslo (Norway); Hop, Haakon [Norwegian Polar Institute, N-9296 Tromsoe (Norway); Muir, Derek C.G. [National Water Research Institute, Environment Canada, Burlington, ON, L7R 4A6 (Canada); Gabrielsen, Geir W. [Norwegian Polar Institute, N-9296 Tromsoe (Norway)

    2005-04-01

    Four seabird species and their prey (zooplankton or fish) were collected in the Barents Sea to determine how dietary exposure, cytochrome P450 (CYP) enzyme activities and sex influenced their hepatic PCB concentrations and accumulation patterns. Five males and five females from each seabird species (little auk (Alle alle), Bruennich's guillemot (Uria lomvia), black guillemot (Cepphus grylle) and black-legged kittiwake (Rissa tridactyla)) were analysed. PCB concentrations could not be explained directly by carbon source ({delta}{sup 13}C) or trophic position ({delta}{sup 15}N), but by a combination of dietary parameters ({delta}{sup 13}C, {delta}{sup 15}N, migratory pattern, age) and contaminant metabolism. Contrary to previous studies, the PCB pattern differed among seabirds, with a higher proportion of persistent congeners (% of PCB-153, R{sub PCB-153}) in black-legged kittiwake than in auks. The PCB pattern also differed among auks, with little auk as the most efficient biotransformer (highest R{sub PCB-153} values of persistent congeners). Based on high R{sub PCB-153} values, Bruennich's guillemot poorly metabolised ortho-meta-unsubstituted congeners, whereas black guillemot poorly metabolised meta-para unsubstituted congeners. Species-specific differences in PCB biotransformation were confirmed by metabolic indices, where PCB patterns in seabirds were adjusted for PCB pattern in prey. The relative contribution of ortho-meta-unsubstituted congeners to {sigma}PCBsdecreased with increasing EROD activity. There were no differences in PCB concentrations, PCB patterns or cytochrome P450 enzyme activities between males and females. CYP P450 activities (CYP1A- and CYP2B/3A-like: EROD and testosterone 6{beta}-hydroxylation, respectively) were low and did not correlate with concentrations of non- or mono-ortho Cl-substituted PCBs (NO- and MO-PCBs), or with total toxic equivalent concentrations (TEQs) for dioxin-like effects of NO- and MO-PCBs. - Contaminant

  11. Dietary exposure to ergot alkaloids decreases contractility of bovine mesenteric vasculature.

    Egert, A M; Kim, D H; Schrick, F N; Harmon, D L; Klotz, J L

    2014-04-01

    vasoactive in the bovine midgut, and steers exposed to E+ had diminished contractility to some ergot alkaloids in small intestinal vasculature. The findings of this study suggest that dietary exposure to ergot alkaloids has the potential to alter nutrient absorption from the midgut by decreasing blood flow to and from the midgut due to vasoconstriction. PMID:24492572

  12. Acute profound thrombocytopenia with second exposure to eptifibatide associated with a strong antibody reaction

    ATTAYA, SHARIFF; KANTHI, YOGENDRA; ASTER, RICHARD; MCCRAE, KEITH

    2015-01-01

    We present a case of eptifibatide-induced acute profound thrombocytopenia in a 64-year-old male receiving eptifibatide for the second time during percutaneous coronary intervention. Although rare, short and self-limited episodes of acute and profound thrombocytopenia have been associated with eptifibatide exposure. The thrombocytopenia is thought to be immune mediated, and assays are available to test for eptifibatide-induced platelet antibodies. PMID:19172524

  13. Acute profound thrombocytopenia with second exposure to eptifibatide associated with a strong antibody reaction

    ATTAYA, SHARIFF; Kanthi, Yogendra; Aster, Richard; McCrae, Keith

    2009-01-01

    We present a case of eptifibatide-induced acute profound thrombocytopenia in a 64-year-old male receiving eptifibatide for the second time during percutaneous coronary intervention. Although rare, short and self-limited episodes of acute and profound thrombocytopenia have been associated with eptifibatide exposure. The thrombocytopenia is thought to be immune mediated, and assays are available to test for eptifibatide-induced platelet antibodies.

  14. Individualised dietary counselling for nutritionally at-risk older patients following discharge from acute hospital to home

    Munk, T; Tolstrup, U; Beck, A M;

    2016-01-01

    ) (MD = 1.01 kg, 95% CI = 0.08-1.95, P = 0.03). Meta-analyses revealed no significant effect on physical function assessed using hand grip strength, and similarly on mortality. Narrative summation of effects on physical function using other instruments revealed inconsistent effects. Meta-analyses were......BACKGROUND: Many older patients are undernourished after hospitalisation. Undernutrition impacts negatively on physical function and the ability of older patients to perform activities of daily living at home after discharge from acute hospital. The present study aimed to evaluate the evidence for...... an effect of individualised dietary counselling following discharge from acute hospital to home on physical function, and, second, on readmissions, mortality, nutritional status, nutritional intake and quality of life (QoL), in nutritionally at-risk older patients. METHODS: A systematic review of...

  15. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli

    Elizabeth Brooke Riley

    2015-08-01

    Full Text Available Psychostimulants have many effects on visual function, from adverse, following acute and prenatal exposure to therapeutic, on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF and dark (DF flashes elicited similar responses in the optic tectum neuropil (TOn, while the dorsal telencephalon (dTe responded only to LF. Acute cocaine (0.5 μM reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals, responses to LF are more complex, involving dTe (homologous to the cerebral cortex, and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that prenatal cocaine exposure modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by prenatal cocaine exposure may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological

  16. Perfluoroalkyl acids and their precursors in Swedish food: The relative importance of direct and indirect dietary exposure

    We analyzed food market basket samples obtained in Sweden from 1999, 2005, and 2010 for perfluoroalkyl acids (PFAAs) and a range of precursor compounds. Perfluorooctane sulfonic acid (PFOS) precursors were detected in all food year pools with the highest concentrations in 1999. Six polyfluoroalkyl phosphate diesters (diPAPs, 4:2/6:2, 6:2/6:2, 6:2/8:2, 8:2/8:2, 6:2/10:2, and 10:2/10:2) were detected in the year pools with the highest ∑diPAP concentrations in 1999 and 2005. All precursors were predominantly found in meat, fish, and/or eggs based on analysis of individual food groups from 1999. Based on year pools, PFOS precursors contributed between 4 and 1% as an indirect source to total dietary PFOS intakes between 1999 and 2010. Perfluorohexanoic acid (PFHxA) exposure originated entirely from diPAPs, whereas for perfluorooctanoic acid (PFOA) and perfluorodecanoic acid (PFDA), diPAPs contributed between 1 and 19% to total exposure. The lowest precursor contributions were generally seen in food samples from 2010. - Highlights: • Three PFOS precursors and six diPAPs were detected in food pools. • Precursor concentrations were highest in 1999 and 2005 food pools, and lowest in 2010. • The relative importance of precursors to total PFOS dietary intake was <4%. • The relative importance of diPAPs as an indirect dietary source of PFCAs was chain length dependent. - The relative contribution of precursors to PFOS dietary intakes is small, whereas the contribution of diPAPs to PFCA dietary intakes varies with the PFCA chain length

  17. Protective effect of dietary antioxidants and plant extracts on acute inflammation and hepatotoxicity in vitro

    El-Saadany, Mohamed Abdel Meged Marawan

    2009-01-01

    Dietary antioxidants are believed to play an important role in the prevention and treatment of a variety of diseases associated with oxidative stress. Although there is a wide range of dietary antioxidants, the bulk of the research to date has been focused on the nutrient antioxidants vitamin C, E, and carotenoids. Certain relatively uncommon antioxidants such as lipoic acid (LA), and phenolic compounds such as (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), a...

  18. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    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......-water after contamination will not die as a result of Se toxicity and can safely be used for human consumption....

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

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

    2015-06-01

    The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. PMID:25896419

  20. Effect of acute dietary nitrate intake on maximal knee extensor speed and power in healthy men and women.

    Coggan, Andrew R; Leibowitz, Joshua L; Kadkhodayan, Ana; Thomas, Deepak P; Ramamurthy, Sujata; Spearie, Catherine Anderson; Waller, Suzanne; Farmer, Marsha; Peterson, Linda R

    2015-08-01

    Nitric oxide (NO) has been demonstrated to enhance the maximal shortening velocity and maximal power of rodent muscle. Dietary nitrate (NO3(-)) intake has been demonstrated to increase NO bioavailability in humans. We therefore hypothesized that acute dietary NO3(-) intake (in the form of a concentrated beetroot juice (BRJ) supplement) would improve muscle speed and power in humans. To test this hypothesis, healthy men and women (n = 12; age = 22-50 y) were studied using a randomized, double-blind, placebo-controlled crossover design. After an overnight fast, subjects ingested 140 mL of BRJ either containing or devoid of 11.2 mmol of NO3(-). After 2 h, knee extensor contractile function was assessed using a Biodex 4 isokinetic dynamometer. Breath NO levels were also measured periodically using a Niox Mino analyzer as a biomarker of whole-body NO production. No significant changes in breath NO were observed in the placebo trial, whereas breath NO rose by 61% (P < 0.001; effect size = 1.19) after dietary NO3(-) intake. This was accompanied by a 4% (P < 0.01; effect size = 0.74) increase in peak knee extensor power at the highest angular velocity tested (i.e., 6.28 rad/s). Calculated maximal knee extensor power was therefore greater (i.e., 7.90 ± 0.59 vs. 7.44 ± 0.53 W/kg; P < 0.05; effect size = 0.63) after dietary NO3(-) intake, as was the calculated maximal velocity (i.e., 14.5 ± 0.9 vs. 13.1 ± 0.8 rad/s; P < 0.05; effect size = 0.67). No differences in muscle function were observed during 50 consecutive knee extensions performed at 3.14 rad/s. We conclude that acute dietary NO3(-) intake increases whole-body NO production and muscle speed and power in healthy men and women. PMID:25199856

  1. Cinnamon intake alleviates the combined effects of dietary-induced insulin resistance and acute stress on brain mitochondria.

    Couturier, Karine; Hininger, Isabelle; Poulet, Laurent; Anderson, Richard A; Roussel, Anne-Marie; Canini, Frédéric; Batandier, Cécile

    2016-02-01

    Insulin resistance (IR), which is a leading cause of the metabolic syndrome, results in early brain function alterations which may alter brain mitochondrial functioning. Previously, we demonstrated that rats fed a control diet and submitted to an acute restraint stress exhibited a delayed mitochondrial permeability transition pore (mPTP) opening. In this study, we evaluated the combined effects of dietary and emotional stressors as found in western way of life. We studied, in rats submitted or not to an acute stress, the effects of diet-induced IR on brain mitochondria, using a high fat/high fructose diet (HF(2)), as an IR inducer, with addition or not of cinnamon as an insulin sensitizer. We measured Ca(2+) retention capacity, respiration, ROS production, enzymatic activities and cell signaling activation. Under stress, HF(2) diet dramatically decreased the amount of Ca(2+) required to open the mPTP (13%) suggesting an adverse effect on mitochondrial survival. Cinnamon added to the diet corrected this negative effect and resulted in a partial recovery (30%). The effects related to cinnamon addition to the diet could be due to its antioxidant properties or to the observed modulation of PI3K-AKT-GSK3β and MAPK-P38 pathways or to a combination of both. These data suggest a protective effect of cinnamon on brain mitochondria against the negative impact of an HF(2) diet. Cinnamon could be beneficial to counteract deleterious dietary effects in stressed conditions. PMID:26878796

  2. Commuters’ air pollution exposure and acute health effects

    Zuurbier, M.M.M.

    2011-01-01

    People spend a substantial proportion of their time in traffic. In Europe, the average daily time in traffic is one to one and a half hour. Because of high in-traffic exposures and because most of the journeys are made during rush hours, the one to one and a half hour in traffic contributes dispropo

  3. Cumulative Exposure to Prior Collective Trauma and Acute Stress Responses to the Boston Marathon Bombings

    Garfin, DR; Holman, EA; Silver, RC

    2015-01-01

    © The Author(s) 2015 The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metrop...

  4. Working memory performance after acute exposure to the cold pressor stress in healthy volunteers

    Duncko, Roman; Johnson, Linda; Merikangas, Kathleen; Grillon, Christian

    2009-01-01

    Effects of acute stress exposure on learning and memory have been frequently studied in both animals and humans. However, only a few studies have focused specifically on working memory performance and the available data are equivocal. The present study examined working memory performance during the Sternberg item recognition task after exposure to a predominantly adrenergic stressor. Twenty four healthy subjects were randomly assigned to a stress group or a control group. The stress group was...

  5. Dietary supplementation of mannan-oligosaccharide enhances neonatal immune responses in chickens during natural exposure to Eimeria spp

    Nava Gerardo M

    2009-03-01

    Full Text Available Abstract Background Control and eradication of intestinal infections caused by protozoa are important biomedical challenges worldwide. Prophylactic control of coccidiosis has been achieved with the use of anticoccidial drugs; however, the increase in anticoccidial resistance has raised concerns about the need for new alternatives for the control of coccidial infections. In fact, new strategies are needed to induce potent protective immune responses in neonatal individuals. Methods The effects of a dietary supplementation of mannan-oligosaccharide (yeast cell wall; YCW on the local, humoral and cell-mediated immune responses, and intestinal replication of coccidia were evaluated in a neonatal animal model during natural exposure to Eimeria spp. A total of 840 one-day-old chicks were distributed among four dietary regimens: A Control diet (no YCW plus anticoccidial vaccine; B Control diet plus coccidiostat; C YCW diet plus anticoccidial vaccination; and D YCW diet plus coccidiostat. Weight gain, feed consumption and immunological parameters were examined within the first seven weeks of life. Results Dietary supplementation of 0.05% of YCW increased local mucosal IgA secretions, humoral and cell-mediated immune responses, and reduced parasite excretion in feces. Conclusion Dietary supplementation of yeast cell wall in neonatal animals can enhance the immune response against coccidial infections. The present study reveals the potential of YCW as adjuvant for modulating mucosal immune responses.

  6. Cement dust exposure and acute lung function: A cross shift study

    Moen Bente E

    2010-04-01

    Full Text Available Abstract Background Few studies have been carried out on acute effects of cement dust exposure. This study is conducted to investigate the associations between current "total" dust exposure and acute respiratory symptoms and respiratory function among cement factory workers. Methods A combined cross-sectional and cross-shift study was conducted in Dire Dawa cement factory in Ethiopia. 40 exposed production workers from the crusher and packing sections and 20 controls from the guards were included. Personal "total" dust was measured in the workers' breathing zone and peak expiratory flow (PEF was measured for all selected workers before and after the shift. When the day shift ended, the acute respiratory symptoms experienced were scored and recorded on a five-point Likert scale using a modified respiratory symptom score questionnaire. Results The highest geometric mean dust exposure was found in the crusher section (38.6 mg/m3 followed by the packing section (18.5 mg/m3 and the guards (0.4 mg/m3. The highest prevalence of respiratory symptoms for the high exposed workers was stuffy nose (85% followed by shortness of breath (47% and "sneezing" (45%. PEF decreased significantly across the shift in the high exposed group. Multiple linear regression showed a significant negative association between the percentage cross-shift change in PEF and total dust exposure. The number of years of work in high-exposure sections and current smoking were also associated with cross-shift decrease in PEF. Conclusions Total cement dust exposure was related to acute respiratory symptoms and acute ventilatory effects. Implementing measures to control dust and providing adequate personal respiratory protective equipment for the production workers are highly recommended.

  7. Risk of dietary exposure to aflatoxins and fumonisins in infants less than 6 months of age in Rombo, Northern Tanzania.

    Magoha, Happy; Kimanya, Martin; De Meulenaer, Bruno; Roberfroid, Dominique; Lachat, Carl; Kolsteren, Patrick

    2016-07-01

    Infants less than 6 months of age receiving foods other than breast milk are at a high risk of exposure to mycotoxins. We surveyed food intake and estimated the risk of exposures to aflatoxin and fumonisin mycotoxins for infants less than 6 months of age in Northern Tanzania. A total of 143 infants were progressively recruited and three follow-up visits were made at 1, 3 and 5 months of age. A 24-h dietary recall technique was used to estimate flour intake of infants who had been introduced to maize foods. Aflatoxins and fumonisins in the flours were analysed using high-performance liquid chromatography technique. Exposure to aflatoxins or fumonisins was estimated using the deterministic approach. By the age of 3 months, 98 infants had started taking food; 67 of them, maize flours at levels ranging from 0.57 to 37.50 g per infant per day (average 8 g per infant per day). Fifty-eight per cent of 67 maize flour samples contained detectable aflatoxins (range 0.33-69.47 μg kg(-1) ; median 6 μg kg(-1) ) and 31% contained detectable fumonisins (range 48-1224 μg kg(-1) ; median 124 μg kg(-1) ). For infants who consumed contaminated flours, aflatoxin exposure ranged from 0.14 to 120 ng kg(-1) body weight (BW) per day (all above the health concern level of 0.017 ng kg(-1) BW per day as recommended by the European Food Safety Agency) and fumonisin exposure ranged from 0.005 to 0.88 μg kg(-1) BW per day. Insignificant association was observed between exposure to fumonisins or aflatoxins and stunting or underweight. Reducing aflatoxin and fumonisin contamination of maize and dietary diversification can prevent infants and the public, in general, from exposure to the toxins. PMID:25422038

  8. The bioaccumulation and effects of selenium in the oligochaete Lumbriculus variegatus via dissolved and dietary exposure routes.

    Xie, Lingtian; Wu, Xing; Chen, Hongxing; Luo, Yongju; Guo, Zhongbao; Mu, Jingli; Blankson, Emmanuel R; Dong, Wu; Klerks, Paul L

    2016-09-01

    Aquatic organisms take up selenium from solution and from their diets. Many questions remain regarding the relative importance of selenium accumulation from these sources and resulting effects in benthic invertebrates. The present study addressed the toxicity and accumulation of Se via dissolved and dietary exposures to three different Se species, in the freshwater oligochaete Lumbriculus variegatus. Worms were exposed to 20μg/g dry weight of selenite (Se(IV)), selenate (Se(VI)), or seleno-l-methionine (Se-Met) in their diet (sediment) or to 15μg/L dissolved Se in water-only exposures. While the dissolved and sediment Se levels differed greatly, such levels may co-occur at a Se-contaminated site. Se accumulation, worm population growth, lipid peroxidation (as TBARS), and Na(+)/K(+)-ATPase activity were quantified at the end of the 2-week exposure. The sediment Se-Met exposure caused 100% mortality, while worm densities were reduced by the other exposures except the Se(VI) one. Se bioaccumulation was generally higher for the sediment-Se exposure than the dissolved-Se ones, and was higher for Se(IV) than Se(VI) in the dissolved-Se exposure but not the sediment-Se one. The Se accumulation was highest for Se-Met. The oligochaetes that accumulated Se had higher levels of lipid peroxidation and reduced Na(+)/K(+)-ATPase activity. The present study's findings of differences in Se accumulation and toxicity for the three Se species, with effects generally but not exclusively a function of Se body burdens, underscore the need for research on these issues in invertebrates. Moreover, the results imply that the dietary uptake route is the predominant one for Se accumulation in L. variegatus. PMID:27450235

  9. The effects of acute radiation exposure on the serum components

    The blood samples were collected from the experimental animals 24 hrs after irradiation of gamma doses upto 80 Gy. Native PAGE showed a decreasing trend in gamma globulin fraction of serum from the irradiated group compared to control, while SDS PAGE indicated an enhanced tendency in protein of molecular weight 30,000 to 40,000. Serum albumin slightly decreased with radiation doses as a result of decrease in total protein amount. Radiation exposure had little or no effects on such lipid related components as phospholipid, triglyceride, and cholesterol, respectively. Among others, glutamic pyryvic transaminase (GPT) showed a drastic decrease in its amount 24 hrs after radiation exposure, which can be applied to the health care program for radiation workers. (Author)

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

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

  11. Dietary exposure to endocrine disrupting chemicals in metropolitan population from China: a risk assessment based on probabilistic approach.

    He, Dongliang; Ye, Xiaolei; Xiao, Yonghua; Zhao, Nana; Long, Jia; Zhang, Piwei; Fan, Ying; Ding, Shibin; Jin, Xin; Tian, Chong; Xu, Shunqing; Ying, Chenjiang

    2015-11-01

    The intake of contaminated foods is an important exposure pathway for endocrine disrupting chemicals (EDCs). However, data on the occurrence of EDCs in foodstuffs are sporadic and the resultant risk of co-exposure is rarely concerned. In this study, 450 food samples representing 7 food categories (mainly raw and fresh food), collected from three geographic cities in China, were analyzed for eight EDCs using high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Besides estrone (E1), other EDCs including diethylstilbestrol (DES), nonylphenol (NP), bisphenol A (BPA), octylphenol (OP), 17β-estradiol (E2), 17α-ethinylestradiol (EE2), and estriol (E3) were ubiquitous in food. Dose-dependent relationships were found between NP and EE2 (r=0.196, plocal food consumption, dietary EDCs exposure was estimated using the Monte Carlo Risk Assessment (MCRA) system. The 50th and 95th percentile exposure of any EDCs isomer were far below the tolerable daily intake (TDI) value identically. However, the sum of 17β-estradiol equivalents (∑EEQs) exposure in population was considerably larger than the value of exposure to E2, which implied the underlying resultant risk of multiple EDCs in food should be concern. In conclusion, co-exposure via food consumption should be considered rather than individual EDCs during health risk evaluation. PMID:26025473

  12. Acute Lung Injury Due To Carbon Monoxide Exposure

    Uzkeser M et al.

    2012-10-01

    Full Text Available A 20-year-old woman, who was found unconscious in the bed by the morning, was brought to emergency department. Her carboxyhemoglobin level was 20.2%. The portable chest X-ray showed bilaterally alveolar and interstitial infiltration. Initial pO 2 /FIO 2 ratio was calculated as 119 mmHg. Acute lung injury due to carbon monoxide intoxication was considered. She was intubated and mechanical ventilation was applied. In the second day of hospitalization, a clear improvement was observed on the chest X-ray. She was discharged without any complication on the seventh day of hospitalization. Early diagnosis and treatment may prevent progression of ARDS and progression of permanent damage, and may lead to complete recovery.

  13. Effects of dietary cadmium exposure on tissue-specific cadmium accumulation, iron status and expression of iron-handling and stress-inducible genes in rainbow trout: Influence of elevated dietary iron

    Kwong, Raymond W.M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Andres, Jose A. [Department of Biology, University of Saskatchewan, Saskatoon, SK, S7N 5E2 (Canada); Niyogi, Som, E-mail: som.niyogi@usask.ca [Department of Biology, University of Saskatchewan, Saskatoon, SK, S7N 5E2 (Canada)

    2011-03-15

    Recent evidences suggest that dietary cadmium (Cd) uptake likely occurs via the dietary iron (Fe) uptake pathway in freshwater fish, at least in part. The present study investigated the interactive effects of dietary Cd and Fe in juvenile rainbow trout (Oncorhynchus mykiss). Fish were treated for four weeks with four different diets: normal Fe, high Fe, normal Fe plus Cd, and high Fe plus Cd. Physiological parameters, tissue-specific Fe and Cd level, plasma Fe status, and tissue-specific mRNA expression of transferrin, metallothioneins (MT-A and MT-B) and heat shock proteins 70 (HSP70a and HSP70b) were analyzed. Exposure to dietary Cd increased Cd burden in the following order: intestine > kidney > stomach > liver > gill > carcass. Interestingly, high dietary Fe reduced Cd accumulation in the stomach and intestine as well as in the wholebody of fish. Dietary Cd increased hepatic transferrin mRNA expression and total Fe binding capacity in the plasma, indicating the effect of Cd on Fe handling in fish. The mRNA expression of MTs and HSP70s was also increased in various tissues following dietary Cd exposure, however the response profile of different MT and HSP70 genes was not consistent among different tissues. In general, MT-A was more responsive to Cd exposure in the intestine and liver, whereas MT-B was more responsive in the kidney. Similarly, HSP70a expression was more sensitive to Cd exposure than HSP70b, particularly in the intestine. Interestingly, high Fe diet suppressed Cd-induced induction of transferrin, MT and HSP70 genes in various tissues. Overall, our study suggests that elevated dietary Fe can reduce Cd accumulation and ameliorate Cd-induced stress responses in freshwater fish.

  14. Quantifying children's aggregate (dietary and residential) exposure and dose to permethrin: application and evaluation of EPA's probabilistic SHEDS-Multimedia model.

    Zartarian, Valerie; Xue, Jianping; Glen, Graham; Smith, Luther; Tulve, Nicolle; Tornero-Velez, Rogelio

    2012-01-01

    Reliable, evaluated human exposure and dose models are important for understanding the health risks from chemicals. A case study focusing on permethrin was conducted because of this insecticide's widespread use and potential health effects. SHEDS-Multimedia was applied to estimate US population permethrin exposures for 3- to 5-year-old children from residential, dietary, and combined exposure routes, using available dietary consumption data, food residue data, residential concentrations, and exposure factors. Sensitivity and uncertainty analyses were conducted to identify key factors, pathways, and research needs. Model evaluation was conducted using duplicate diet data and biomonitoring data from multiple field studies, and comparison to other models. Key exposure variables were consumption of spinach, lettuce, and cabbage; surface-to-skin transfer efficiency; hand mouthing frequency; fraction of hand mouthed; saliva removal efficiency; fraction of house treated; and usage frequency. For children in households using residential permethrin, the non-dietary exposure route was most important, and when all households were included, dietary exposure dominated. SHEDS-Multimedia model estimates compared well to real-world measurements data; this exposure assessment tool can enhance human health risk assessments and inform children's health research. The case study provides insights into children's aggregate exposures to permethrin and lays the foundation for a future cumulative pyrethroid pesticides risk assessment. PMID:22434114

  15. Effects of Parental Dietary Exposure to GMRice TT51 on the Male Reproductive System of Rat Off spring

    WANG Er Hui; YU Zhou; JIA Xu Dong; ZHANG Wen Zhong; andXU Hai Bin

    2016-01-01

    ObjectiveTo evaluatethehealth effects of parental dietary exposure to GM rice TT51 on the male reproductive system of rat offspring. MethodsRice-based diets, containing 60% ordinary grocery rice, MingHui63, or TT51 by weight, were given to parental rats (15 males/30 females each group) for 70 days prior mating and throughout pregnancy and lactation. After weaning, eightmale offspringratswere randomly selected at each group and fed with dietscorrespondent to their parents’ for 70 days. The effects of exposure to TT51 on male reproductive system of offspring rats were assessed through sperm parameters, testicular function enzyme activities, serumhormones (FSH, LH, and testosterone levels), testis histopathological examination, and the relativeexpression levels of selected genes along the hypothalamic-pituitary-testicular (HPT) axis. ResultsNo significant differences were observed in body weight, food intake, organ/body weights, serum hormone, sperm parameters, testis function enzyme ACP, LDH, and SDH activities, testis histopathological changes, and relative mRNA expression levels of GnRH-R, FSH-R, LH-R, and AR along the HPT axis. ConclusionThe resultsof this studydemonstrate that parental dietary exposure to TT51 reveals no significant differences on the reproductive system of male offspring rats compared with MingHui63 and control.

  16. Hepatic and renal trace element concentrations in American alligators (Alligator mississippiensis) following chronic dietary exposure to coal fly ash contaminated prey.

    Tuberville, Tracey D; Scott, David E; Metts, Brian S; Finger, John W; Hamilton, Matthew T

    2016-07-01

    Little is known about the propensity of crocodilians to bioaccumulate trace elements as a result of chronic dietary exposure. We exposed 36 juvenile alligators (Alligator mississippiensis) to one of four dietary treatments that varied in the relative frequency of meals containing prey from coal combustion waste (CCW)-contaminated habitats vs. prey from uncontaminated sites, and evaluated tissue residues and growth rates after 12 mo and 25 mo of exposure. Hepatic and renal concentrations of arsenic (As), cadmium (Cd) and selenium (Se) varied significantly among dietary treatment groups in a dose-dependent manner and were higher in kidneys than in livers. Exposure period did not affect Se or As levels but Cd levels were significantly higher after 25 mo than 12 mo of exposure. Kidney As and Se levels were negatively correlated with body size but neither growth rates nor body condition varied significantly among dietary treatment groups. Our study is among the first to experimentally examine bioaccumulation of trace element contaminants in crocodilians as a result of chronic dietary exposure. A combination of field surveys and laboratory experiments will be required to understand the effects of different exposure scenarios on tissue residues, and ultimately link these concentrations with effects on individual health. PMID:27149145

  17. Influence of dietary patterns on the risk of acute myocardial infarction in China population: the INTERHEART China study

    GUO Jin; LI Wei; WANG Yang; CHEN Tao; Koon Teo; LIU Li-sheng

    2013-01-01

    Background Some dietary patterns are risk factors for acute myocardial infarction (AMI).Chinese traditional food and habits vary from other cultures.The present study determined whether different dietary patterns were associated with AMI in Chinese people.Methods We conducted a case-control study.There were 1312 cases of first AMI and 2235 control subjects who did not have previous angina,diabetes mellitus,hypertension or stroke.Controls were matched to cases on age and gender.Diet was measured with a validated,19 item food frequency questionnaire.We identified three major dietary patterns using factor analysis:vitamin and microelement pattern (high intake of vegetables,fruits and tofu),carbohydrate pattern (high in grain),and fat and protein pattern (high in meat,fish,eggs and fried foods).Results After adjusting for all risk factors,the vitamin and microelement pattern was inversely associated with AMI risk (global P value,0.0001).Compared with the first quartile,the adjusted ORs of AMI were 0.81 (95% CI:0.66-1.00) for the second quartile,0.67 (95% CI:0.54-0.82) for the third,and 0.70 (95% CI:0.56-0.88) for the fourth.Several dietary frequencies (serves per week) including vegetables,fruits and tofu were closely associated with decrease of AMI risk.Carbohydrate pattern showed weak relationship with AMI.We observed a U-shaped association between frequencies of fat and protein pattern and AMI risk.Excessive fat intake increased the AMI risk.The adjusted OR of AMI associated with the higher level of green vegetables was 0.37 (95% CI:0.24-0.57) in women and 0.65 (95% CI:0.51-0.82) in men (P value for heterogeneity,0.0140).Conclusions Unhealthy dietary intake can increase the AMI risk.Improving intake of vegetables,fruits and tofu have the potential to partially prevent the rising epidemic of cardiovascular disease in China.

  18. Ochratoxin A Dietary Exposure of Ten Population Groups in the Czech Republic: Comparison with Data over the World

    Vladimir Ostry

    2015-09-01

    Full Text Available Ochratoxin A is a nephrotoxic and renal carcinogenic mycotoxin and is a common contaminant of various food commodities. Eighty six kinds of foodstuffs (1032 food samples were collected in 2011–2013. High-performance liquid chromatography with fluorescence detection was used for ochratoxin A determination. Limit of quantification of the method varied between 0.01–0.2 μg/kg depending on the food matrices. The most exposed population is children aged 4–6 years old. Globally for this group, the maximum ochratoxin A dietary exposure for “average consumer” was estimated at 3.3 ng/kg bw/day (lower bound, considering the analytical values below the limit of quantification as 0 and 3.9 ng/kg bw/day (middle bound, considering the analytical values below the limit of quantification as 1/2 limit of quantification. Important sources of exposure for this latter group include grain-based products, confectionery, meat products and fruit juice. The dietary intake for “high consumers” in the group 4–6 years old was estimated from grains and grain-based products at 19.8 ng/kg bw/day (middle bound, from tea at 12.0 ng/kg bw/day (middle bound and from confectionery at 6.5 ng/kg bw/day (middle bound. For men aged 18–59 years old beer was the main contributor with an intake of 2.60 ng/kg bw/day (“high consumers”, middle bound. Tea and grain-based products were identified to be the main contributors for dietary exposure in women aged 18–59 years old. Coffee and wine were identified as a higher contributor of the OTA intake in the population group of women aged 18–59 years old compared to the other population groups.

  19. Ochratoxin A Dietary Exposure of Ten Population Groups in the Czech Republic: Comparison with Data over the World.

    Ostry, Vladimir; Malir, Frantisek; Dofkova, Marcela; Skarkova, Jarmila; Pfohl-Leszkowicz, Annie; Ruprich, Jiri

    2015-09-01

    Ochratoxin A is a nephrotoxic and renal carcinogenic mycotoxin and is a common contaminant of various food commodities. Eighty six kinds of foodstuffs (1032 food samples) were collected in 2011-2013. High-performance liquid chromatography with fluorescence detection was used for ochratoxin A determination. Limit of quantification of the method varied between 0.01-0.2 μg/kg depending on the food matrices. The most exposed population is children aged 4-6 years old. Globally for this group, the maximum ochratoxin A dietary exposure for "average consumer" was estimated at 3.3 ng/kg bw/day (lower bound, considering the analytical values below the limit of quantification as 0) and 3.9 ng/kg bw/day (middle bound, considering the analytical values below the limit of quantification as 1/2 limit of quantification). Important sources of exposure for this latter group include grain-based products, confectionery, meat products and fruit juice. The dietary intake for "high consumers" in the group 4-6 years old was estimated from grains and grain-based products at 19.8 ng/kg bw/day (middle bound), from tea at 12.0 ng/kg bw/day (middle bound) and from confectionery at 6.5 ng/kg bw/day (middle bound). For men aged 18-59 years old beer was the main contributor with an intake of 2.60 ng/kg bw/day ("high consumers", middle bound). Tea and grain-based products were identified to be the main contributors for dietary exposure in women aged 18-59 years old. Coffee and wine were identified as a higher contributor of the OTA intake in the population group of women aged 18-59 years old compared to the other population groups. PMID:26378578

  20. Exploration of different methods to assess dietary acrylamide exposure in pregnant women participating in the Norwegian Mother and Child Cohort Study (MoBa)

    Brantsaeter, A.L.; Haugen, M.; Mul, de A.; Bjellaas, T.; Becher, G.; Klaveren, van J.D.; Alexander, J.; Meltzer, H.M.

    2008-01-01

    We assessed dietary exposure to acrylamide in 119 pregnant Norwegian women. The aim of the study was to explore three different methods for estimation of long-term intake of acrylamide and whether it is possible by a food frequency questionnaire (FFQ) to identify pregnant women with high exposure to

  1. Chronic dietary mercury exposure causes oxidative stress, brain lesions, and altered behaviour in Atlantic salmon (Salmo salar) parr

    Berntssen, Marc H.G.; Aatland, Aase; Handy, Richard D

    2003-10-08

    Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal based diets supplemented with mercuric chloride (0, 10, or 100 mg Hg kg{sup -1} DW) or methylmercury chloride (0, 5, or 10 mg Hg kg{sup -1} DW) to assess the effects of inorganic (Hg) and organic dietary mercury on brain lipid peroxidation and neurotoxicity. Lipid peroxidative products, endogenous anti oxidant enzymes, brain histopathology, and overall behaviour were measured. Methylmercury accumulated significantly in the brain of fish fed 5 or 10 mg kg{sup -1} by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg{sup -1} exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg{sup -1} methylmercury had a significant increase (2-fold) in the antioxidant enzyme super oxide dismutase (SOD) in the brain. At dietary levels of 10 mg kg{sup -1} methylmercury, a significant increase (7-fold) was observed in lipid peroxidative products (thiobarbituric acid reactive substances, TBARS) and a subsequently decrease (1.5-fold) in anti oxidant enzyme activity (SOD and glutathione peroxidase, GSH-Px). Fish fed 10 mg kg{sup -1} methylmercury also had pathological damage (vacoulation and necrosis), significantly reduced neural enzyme activity (5-fold reduced monoamine oxidase, MAO, activity), and reduced overall post-feeding activity behaviour. Pathological injury started in the brain stem and became more widespread in other areas of the brain at higher exposure levels. Fish fed 100 mg Hg kg{sup -1} inorganic mercury had significant reduced neural MAO activity and pathological changes (astrocyte proliferation) in the brain, however, neural SOD and GSH-Px enzyme activity, lipid peroxidative products (TBARS), and post feeding behaviour did not differ from controls. Compared with other organs, the brain is particular susceptible for dietary methylmercury induced lipid peroxidative stress at relative low

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

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

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

    Shannahan, Jonathan H. [Curriculum in Toxicology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599 (United States); Alzate, Oscar [Systems Proteomics Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599 (United States); Winnik, Witold M.; Andrews, Debora [Proteomics Core, Research Core Unit, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Schladweiler, Mette C. [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Ghio, Andrew J. [Clinical Research Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Chapel Hill, NC 27599 (United States); Gavett, Stephen H. [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Kodavanti, Urmila P., E-mail: Kodavanti.Urmila@epa.gov [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States)

    2012-04-15

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

  4. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice.

    Tallarida, Christopher S; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-11-27

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this question using C57BL/6 mice. Mice pretreated with cocaine (15mg/kg×14 days) and then challenged with cocaine (15mg/kg) after 30 days of cocaine absence displayed sensitization of locomotor activity. For combination experiments, CTX injected during the 30 days of cocaine absence attenuated behavioral sensitization produced by cocaine challenge. In the case in which CTX was injected together with cocaine for 14 days, development of behavioral sensitization to cocaine challenge was also reduced. CTX attenuated the increase in locomotor activity produced by acute cocaine exposure; however, its efficacy was dependent on the dose of cocaine as inhibition was detected against 30mg/kg, but not 15mg/kg, of cocaine. These results from mice indicate that CTX attenuates locomotor activity produced by acute and repeated cocaine exposure and counters cocaine's locomotor activating properties in a paradigm in which the antibiotic is injected during the period of forced cocaine absence that follows repeated cocaine exposure. PMID:24120434

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

    Laloy, J., E-mail: julie.laloy@unamur.be [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Lozano, O. [University of Namur (UNamur), Research Centre in Physics of Matter and Radiation (PMR), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium); Alpan, L.; Masereel, B. [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Toussaint, O. [University of Namur (UNamur), Laboratory of Cellular Biochemistry and Biology (URBC), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium); Dogné, J. M. [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Lucas, S. [University of Namur (UNamur), Research Centre in Physics of Matter and Radiation (PMR), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium)

    2015-08-15

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

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

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

  7. Human semen quality in relation to dietary pesticide exposure and organic diet

    Juhler, R. K.; Larsen, S. B.; Meyer, Otto A.;

    1999-01-01

    The objective of the study was to corroborate or refute the hypothesis that farmers having a high intake of organic grown commodities have a high semen quality due to their expected lower level of dietary pesticides intake. Food frequency data and semen were collected from 256 farmers (171...... mean intake of single commodities, such as rice, potato, and pork meat. The current individual dietary intake of 40 pesticides was estimated using food frequencies and generalized serving size data in combination with data on pesticide concentrations in food commodities as obtained from the National...... Danish Food Monitoring Program. The estimated pesticide intake was significantly lower among farmers of group H, but for all three groups of farmers the average dietary intake of 40 pesticides was at or below 1% of the acceptable daily intake (ADI) except for the dithiocarbamates (max = 0.21 mu g/kg day...

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

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

  9. Effects of Acute Exposures to Carbon Dioxide Upon Cognitive Functions

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

    2016-01-01

    Large quantities of carbon dioxide (CO2) originate from human metabolism and typically, within spacecraft, remain about 10-fold higher in concentration than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the International Space Station (ISS) that associates CO2 levels with reports of headaches by crewmembers. Additionally, there is concern that CO2 may contribute to vision impairment and intracranial pressure that has been observed in some crewmembers. Consequently, flight rules have been employed to control the level of CO2 below 4 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. However, the flight rule imposed limit, which places additional demands upon resources and current technology, still exceeds the lower bound of the threshold range for reportable headaches (2 - 5 mm Hg). Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached. The causes of the headaches may elicit other subtle adverse effects that occur at CO2 levels well below that for headaches. The concern that CO2 may have effects at levels below the threshold for headaches appears to be substantiated in unexpected findings that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. If findings of the earlier study are confirmed in crew-like subjects, our findings would provide additional evidence that CO2 may need to be

  10. Dietary and inhalation exposure to polycyclic aromatic hydrocarbons and urinary excretion of monohydroxy metabolites – A controlled case study in Beijing, China

    Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs. Highlights: • The dependence of urinary OHPAHs on PAH intake was explored. • Consumption of lamb kabob resulted in large increase of most urinary OHPAHs. • Gender differences in PAH metabolism was observed. • Urinary metabolites of PHE and PYR can be used as biomarkers for dietary PAH intake. • Urinary 3-BaA may serve as the indicator for the inhalation exposure to BaPeq. -- Severe exposure to PAHs via dietary and inhalation pathways indicated by the intake of parent PAHs as well as the urinary excretion of OHPAHs, was observed for students in Beijing

  11. exposure of growing and adult captive cheetahs (Acinony Jubatus) to dietary isoflavones: twenty years later

    Bell, K.M.; Rutherfurd, S.M.; Hendriks, W.H.

    2010-01-01

    Dietary isoflavones are associated with oestrogenic and anti-oestrogenic effects, and have been linked to infertility in cheetahs. This study aimed to determine the isoflavone content of commercially prepared diets consumed by captive cheetahs. Sixteen international zoological facilities provided di

  12. Biomarkers of Dietary Exposure Are Associated with Lower Risk of Breast Fibroadenomas in Chinese Women

    Dijkstra, S.C.; Lampe, J.W.; Ray, R.M.; Brown, R.; Wu, C.Y.; Li, W.J.; Chen, C.; King, I.B.; Gao, D.L.; Hu, Y.W.; Shannon, J.; Wahala, K.; Thomas, D.B.

    2010-01-01

    Fibroadenomas are the most common benign breast condition among women and account for up to 50% of all breast biopsies being performed. Although considered a benign condition, fibroadenomas utilize substantial resources for management and treatment to rule out potential malignancies. Dietary factors

  13. Accumulation and effects of Cr(VI) in Japanese medaka (Oryzias latipes) during chronic dissolved and dietary exposures.

    Chen, Hongxing; Mu, Lei; Cao, Jinling; Mu, Jingli; Klerks, Paul L; Luo, Yongju; Guo, Zhongbao; Xie, Lingtian

    2016-07-01

    Chromium (Cr) is an essential metal and a nutritional supplement for both human and agricultural uses. It is also a pollutant from a variety of industrial uses. These uses can lead to elevated Cr levels in aquatic environments, where it can enter and affect aquatic organisms. Its accumulation and subsequent effects in fish have received relatively little attention, especially for chronic exposure. In the present study, Japanese medaka were chronically exposed to dissolved or dietary Cr(VI) for 3 months. Cr accumulation in liver, gills, intestine, and brain was evaluated. Effects on the antioxidant system, nervous system (acetylcholinesterase, AChE), digestive system (α-glucosidase, α-Glu), and tissue histology (liver and gills) were also assessed. Cr accumulation was observed in the intestine and liver of fish exposed to Cr-contaminated brine shrimp. However, chronic dissolved Cr exposure led to significant Cr accumulation in all organs tested. Analysis of the subcellular distribution of Cr in medaka livers revealed that 37% of the Cr was present in the heat stable protein fraction. The dissolved Cr exposure had pronounced effects on the antioxidant system in the liver, with an elevated ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and decreases in GSH and glutathione S-transferase (GST). The α-Glu activity in the intestine was significantly inhibited. In addition, Cr exposure caused histopathological alterations in the gills and liver. In general, the effects of dietary Cr were relatively minor, possible due to the much lower accumulation in the fish. Our results imply that Japanese medaka accumulate Cr mainly via uptake of dissolved Cr(VI). PMID:27162070

  14. Characterisation of cochlear inflammation in mice following acute and chronic noise exposure.

    Tan, Winston J T; Thorne, Peter R; Vlajkovic, Srdjan M

    2016-08-01

    Oxidative stress has been established as the key mechanism of the cochlear damage underlying noise-induced hearing loss, however, emerging evidence suggests that cochlear inflammation may also be a major contributor. This study aimed to improve our understanding of the cochlear inflammatory response associated with acute and chronic noise exposure. C57BL/6 mice were exposed to acute traumatic noise (100 dBSPL, 8-16 kHz for 24 h) and their cochleae collected at various intervals thereafter, up to 7 days. Using quantitative RT-PCR and immunohistochemistry, changes in expression levels of proinflammatory cytokines (TNF-α, IL-1β), chemokines (CCL2) and cell adhesion molecules (ICAM-1) were studied. All gene transcripts displayed similar dynamics of expression, with an early upregulation at 6 h post-exposure, followed by a second peak at 7 days. ICAM-1 immunoexpression increased significantly in the inferior region of the spiral ligament, peaking 24 h post-exposure. The early expression of proinflammatory mediators likely mediates the recruitment and extravasation of inflammatory cells into the noise-exposed cochlea. The occurrence of the latter expression peak is not clear, but it may be associated with reparative processes initiated in response to cochlear damage. Chronic exposure to moderate noise (90 dBSPL, 8-16 kHz, 2 h/day, up to 4 weeks) also elicited an inflammatory response, reaching a maximum after 2 weeks, suggesting that cochlear damage and hearing loss associated with chronic environmental noise exposure may be linked to inflammatory processes in the cochlea. This study thus provides further insight into the dynamics of the cochlear inflammatory response induced by exposure to acute and chronic noise. PMID:27109494

  15. Growth and reproductive effects from dietary exposure to Aroclor 1268 in mink (Neovison vison), a surrogate model for marine mammals.

    Folland, William R; Newsted, John L; Fitzgerald, Scott D; Fuchsman, Phyllis C; Bradley, Patrick W; Kern, John; Kannan, Kurunthachalam; Remington, Richard E; Zwiernik, Matthew J

    2016-03-01

    Polychlorinated biphenyls (PCBs) from the commercial mixture Aroclor 1268 were historically released into the Turtle-Brunswick River estuary (southeastern Georgia, USA) from industrial operations. Sum PCBs (ΣPCBs) in blubber samples from Turtle-Brunswick River estuary bottlenose dolphins (Tursiops truncatus) have been reported at concentrations more than 10-fold higher than those observed in dolphins from adjacent regional estuaries. Given that toxicity data specific to Aroclor 1268 and applicable to marine mammals are limited, predicting the toxic effects of Aroclor 1268 in dolphins is uncertain, particularly because of its unique congener profile and associated physiochemical characteristics compared with other PCB mixtures. American mink (Neovison vison) were chosen as a surrogate model for cetaceans to develop marine mammalian PCB toxicity benchmarks. Mink are a suitable surrogate species for cetaceans in toxicity studies because of similarities in diet and taxonomic class, and a characteristic sensitivity to PCBs provides a potential safety factor when using mink toxicology data for cross-species extrapolations. Effects of dietary exposure to Aroclor 1268 on reproduction, growth, and mortality in mink were compared with both a negative control and a positive control (3,3',4,4',5-pentachlorobiphenyl, PCB 126). Aroclor 1268 dietary ΣPCB concentrations ranged from 1.8 µg/g feed wet weight to 29 µg/g feed wet weight. Whelp success was unaffected by Aroclor 1268 exposure at any level. Treatment mean litter size, kit growth, and kit survival were adversely affected relative to the negative control at dietary ΣPCB concentrations of 10.6 µg/g feed wet weight and greater. PMID:26313468

  16. Dietary Exposure of Fathead Minnows to the Explosives TNT and RDX and to the Pesticide DDT using Contaminated Invertebrates

    Guilherme R. Lotufo

    2005-08-01

    Full Text Available Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT, a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas. Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario.

  17. Dietary exposure of the red-crowned crane (Grus japonensis) to total and methyl mercury in Zhalong Wetland, northeastern China.

    Luo, Jinming; Ye, Yajie; Wang, Yongjie

    2014-06-01

    To determine the dietary exposure of the migratory red-crowned crane to mercury (Hg), this study analyzed the concentrations of total mercury (T-Hg) and methyl mercury (MeHg) in its prey, i.e., reeds and three aquatic animal families (Perccottus glenni Dybowski, Cybister japonicus Sharp, and Viviparidae) in northeastern China. Results indicated that the Hg concentration in Zhalong Wetland was elevated through the food chain, and the prey of the red-crowned crane contained measurable levels of T-Hg and MeHg. In prey tissues, MeHg was the main form of the Hg element and accounted for 61% of total Hg concentration in Viviparidae, 58% in C. japonicus Sharp, and 85% in P. glenni Dybowski. The highest T-Hg and MeHg concentrations ranged from 1.66 to 3.89 ppm and from 1.12 to 2.67 ppm, respectively, and they were detected in the feathers of the red-crowned cranes. The lowest T-Hg concentration was determined in the excretions of wild red-crowned cranes at 0.21 ppm; furthermore, the content of MeHg was below the detection limit. In Zhalong Wetland, the level of dietary exposure of the population of red-crowned cranes to Hg is below the threshold of Hg toxicity. Moreover, eggshells are suitable indicators of Hg risk levels to the red-crowned crane. PMID:24793423

  18. Toxicity levels to humans during acute exposure to hydrogen fluoride - An update

    In March 1993, the Atomic Energy Control Board (AECB) commissioned and update of a 1984 review on the acute toxicity of hydrogen fluoride (HF). The study places particular emphasis on the effects of inhalation of gaseous HF and is divided into two main parts: a literature review and a lethal concentration (LC) estimation. The literature review summarizes data under four categories: animal studies, controlled human studies, community exposure, and industrial exposure. Data in these areas were critically reviewed for their relevance to lethal concentrations at LCLO, LC10 and LC50 levels that were derived in the 1984 report. In the last ten years, only one relevant animal study has been published. No new controlled human studies were found but a community exposure incident was reported. There were three new industrial/accidental exposures reported since 1984. Evaluation of new data does not change the lethal concentration estimates made in the 1984 report, but does indicate the absence of appropriate models to estimate the lethality of irritant and corrosive gases. In the last 10 years, much literature on the evaluation of major hazards has been published and suggests that such assessments are of growing political, economic and social importance. Numerous articles have been published on the acute toxicity of HF from skin contact and chronic toxicity from repeated airborne exposure. These publications offer important insights into the nature of HF toxicity. Several avenues of investigative research are suggested. (author). 55 refs., 4 tabs

  19. High precision liquid chromatography analysis of dopaminergic and serotoninergic responses to acute alcohol exposure in zebrafish

    Chatterjee, Diptendu; Gerlai, Robert

    2009-01-01

    Zebrafish is gaining popularity in behavioral neuroscience in general and in alcohol research in particular. Alcohol is known to affect numerous molecular mechanisms depending on dose and administration regimen. Prominent among these mechanisms are several neurotransmitter systems. Here we analyze the responses of the dopaminergic and serotoninergic neurotransmitter systems of zebrafish to acute alcohol treatment (1 h long exposure of adult fish to 0.00%, 0.25%, 0.50%, or 1.00% ethyl alcohol)...

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

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

    2015-01-01

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

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

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

    2016-05-01

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

  2. Chronic dietary exposure to pesticide residues and associated risk in the French ELFE cohort of pregnant women.

    de Gavelle, Erwan; de Lauzon-Guillain, Blandine; Charles, Marie-Aline; Chevrier, Cécile; Hulin, Marion; Sirot, Véronique; Merlo, Mathilde; Nougadère, Alexandre

    2016-01-01

    Dietary exposure to pesticide residues may present a risk to public health, especially for sensitive populations such as pregnant women. To characterize this risk, this study assessed chronic dietary exposure to pesticide residues based on the French ELFE cohort. A self-administered food frequency questionnaire (FFQ) about the last three months of pregnancy filled in by pregnant women in 2011 was used in combination with occurrence data from French Total Diet Studies completed by the results of national monitoring programs on pesticide residues in food. The dietary intake of pesticides (μg/kg of body weight/day) was estimated for 14,099 pregnant women with a complete FFQ, for 317 substances under two occurrence scenarios to handle left-censored data: a lower-bound scenario (LB), where undetected results were set to zero, and an upper-bound scenario (UB), where undetected results were set to the detection limit if the substance was expected to be found in food and zero if it was not. The risk was assessed for 284 substances with a toxicological reference value (TRV) and a good coverage level of the diet potentially contributing to pesticide intake. The cumulative risk was also assessed for seven effects on nervous and thyroid systems using the hazard index and the Cumulative Assessment Groups defined by EFSA. Substances with the highest exposure levels under the LB scenario were, in decreasing order, imazalil, piperonyl butoxide, chlorpropham, thiabendazole, iprodione and propargite. Under the LB scenario, only for lindane did women have a statistically significant probability of exceeding the TRV (2.4%). Under the UB scenario, risk could not be excluded for nine other substances. A better management of left-censored data and more sensitive analyses of the main food contributors might help to refine the UB exposure and risk assessments. A statistically significant cumulative risk was found for neurochemical effects related to high intake levels of three

  3. Acute oral intake of a higenamine-based dietary supplement increases circulating free fatty acids and energy expenditure in human subjects

    Lee, Sang-Rok; Schriefer, JohnHenry M; Trint A. Gunnels; Harvey, Innocence C; Bloomer, Richard J

    2013-01-01

    Background Higenamine, also known as norcoclaurine, is an herbal constituent thought to act as a beta-2 adrenergic receptor agonist—possibly stimulating lipolysis. It was the purpose of this study to determine the impact of a higenamine-based dietary supplement on plasma free fatty acids and energy expenditure following acute oral ingestion. Methods Sixteen healthy subjects (8 men; 26.1 ± 2.5 yrs; 8 women 22.4 ± 3.1 yrs) ingested a dietary supplement containing a combination of higenamine, ca...

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

    Maylla Ronacher Simões

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

  5. Chemosensory effects during acute exposure to N-methyl-2-pyrrolidone (NMP).

    van Thriel, Christoph; Blaszkewicz, Meinolf; Schäper, Michael; Juran, Stephanie A; Kleinbeck, Stefan; Kiesswetter, Ernst; Wrbitzky, Renate; Stache, Jürgen; Golka, Klaus; Bader, Michael

    2007-12-10

    Organic solvents are still essential in many industrial applications. To improve safety and health in the working environment lower occupational thresholds limits have been established and less toxic substitutes were introduced. N-Methyl-2-pyrrolidone (NMP) is a versatile solvent that is used as a substitute for dichloromethane in paint strippers. Due to conflicting results, there is a debate whether NMP causes irritations of the upper airways/eyes or not. In a human experimental study we examined the chemosensory effects of NMP under controlled conditions. Fifteen healthy males were investigated in a cross-over study. NMP vapor concentrations were 10, 40 and 80 mg/m(3) for 2 x 4h with an exposure-free lunch break of 30 min. To maximize chemosensory effects a peak exposure scenario (25mg/m(3) baseline, 160 mg/m(3) peaks 4 x 15 min, time-weighted average: 72 mg/m(3)) was tested. The four different conditions were conducted with and without moderate physical workload. Chemosensory effects were measured physiologically by anterior rhinomanometry, eye blink rate and breathing frequency. Subjectively, ratings of acute health symptoms and intensity of olfactory and trigeminal sensations were collected repeatedly throughout the exposures. All physiological variables were unaffected by the different NMP concentrations and even the peak exposures were non-effective on these measures. Olfactory mediated health symptoms increased dose-dependently. For these symptoms a strong adaptation was observable, especially during the first 4h of the exposures. Other acute symptoms were not significantly affected. Comparable to the symptoms, only olfactory sensations increased dose-dependently. Trigeminal sensations (e.g. eye and nose irritations) were evaluated as being barely detectable during the different exposures, only during 160 mg/m(3) exposure peak weak and transient eye irritation were reported. The results clearly suggest that NMP concentrations of up to 160 mg/m(3) caused no

  6. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution.

    Ashley P Pettit

    Full Text Available Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46-70 years were taken on a 1.5 hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics.

  7. Comparative sensitivity of three populations of the cladoceran Moinodaphnia macleayi to acute and chronic uranium exposure.

    Semaan, M; Holdway, D A; van Dam, R A

    2001-10-01

    Assessment of differences in the response of three different populations of the tropical cladoceran Moinodaphnia macleayi to uranium exposure was evaluated. The populations tested included a laboratory stock (maintained for 10 years), a wild population collected from Bowerbird Billabong (an uncontaminated environment), and a population collected from Djalkmara Billabong (a relatively contaminated environment with elevated levels of uranium), located on the Ranger uranium mine site, Jabiru East, NT, Australia. Chronic and acute toxicity of uranium was determined for all three populations. The no-observed-effect-concentration (NOEC; reproduction) and lowest observed-effect-concentration (LOEC; reproduction) for uranium ranged between 8-31 micrograms L-1 and 20-49 micrograms L-1, respectively, for all three populations. The 48 h EC50 (immobilization-lethality) for uranium ranged between 160-390 micrograms L-1 for all three populations. There was little difference in the response of the three populations of M. macleayi to acute and chronic uranium exposure, although the response of the laboratory population to chronic uranium exposure appeared more variable than the "wild" populations. There was no apparent tolerance in the population of M. macleayi obtained from Djalkmara Billabong when exposed to elevated levels of uranium. M. macleayi was significantly more sensitive to uranium exposure than other species previously tested. It was concluded that the sensitivity of the laboratory population (to uranium) is still representative of natural M. macleayi populations. PMID:11594022

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

    Mehinto, Alvine C., E-mail: alvinam@sccwrp.org [Southern California Coastal Water Research Project, Costa Mesa, CA 92626 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Prucha, Melinda S. [Department of Human Genetics, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Colli-Dula, Reyna C.; Kroll, Kevin J.; Lavelle, Candice M.; Barber, David S. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Vulpe, Christopher D. [Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720 (United States); Denslow, Nancy D. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States)

    2014-07-01

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

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

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

  10. Effect of Alcohol Administration on Blood Sugar of Normal and Alcohol Habituated Rates during Acute Cold Exposure

    K. K. Srivastava

    1968-10-01

    Full Text Available Thermoregulatory failure of alcohol administered fasted rates has been studied under acute cold stress. Twentyfour hour fasted rates developed acute hypoglycemia on being given a single oral dose of ethanol (1.3g/kg body weight during a two hour exposure at -20 degree calcius. Alcohol habituated rates, under similar conditions, more or less maintained their blood sugar concentration.

  11. Acute exposure to a 60 Hz magnetic field increases DNA strand breaks in rat brain cells

    Lai, H.; Singh, N.P. [Univ. of Washington, Seattle, WA (United States)

    1997-05-01

    Acute exposure of rats to a 60 Hz magnetic field caused a dose-dependent increase in DNA strand breaks in brain cells of the animals (assayed by a microgel electrophoresis method at 4 h postexposure). An increase in single-strand DNA breaks was observed after exposure to magnetic fields of 0.1, 0.25, and 0.5 mT, whereas an increase in double-strand DNA breaks was observed at 0.25 and 0.5 mT. Because DNA strand breaks may affect cellular functions, lead to carcinogenesis and cell death, and be related to onset of neurodegenerative diseases, the data may have important implications for the possible health effects of exposure to 60 Hz magnetic fields.

  12. Acute myocardial infarction associated with dietary supplements containing 1,3-dimethylamylamine and Citrus aurantium.

    Smith, Triston B; Staub, Brian A; Natarajan, Gayathri M; Lasorda, David M; Poornima, Indu G

    2014-02-01

    We describe the case of a previously healthy 22-year-old man who presented with anginal chest pain and was diagnosed with a non-ST-elevation myocardial infarction. For 3 weeks, he had been ingesting the dietary supplements Jack3d® (principal ingredient, 1,3-dimethylamylamine) and Phenorex™ (principal ingredient, Citrus aurantium) daily, before undertaking physical activity. Coronary angiograms revealed a proximal left anterior descending coronary artery thrombus with distal embolization. A combined medical regimen led to resolution of the thrombus. Three months later, the patient was asymptomatic with no evidence of ischemia. The primary ingredients in the sympathomimetic supplements taken by our patient are controversial in the medical community and have been individually associated with adverse cardiac events. There are no safety data on their simultaneous use. We discuss other reports of adverse effects associated with these supplements and recommend that the relevant safety guidelines be revised. PMID:24512406

  13. Risk Assessment on Dietary Exposure to Aflatoxin B1 in Post-Harvest Peanuts in the Yangtze River Ecological Region

    Xiaoxia Ding

    2015-10-01

    Full Text Available Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R2 of multiple regression reflected by the aflatoxin B1 content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B1 contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B1 intake from peanuts at the mean peanut consumption level was 0.777–0.790 and 0.343–0.349 ng/(kg·d for children aged 2–6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year respectively, generally less than China’s current liver cancer incidence of 24.6 cases/(100,000 persons·year. In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B1 contamination risk assessment in order to protect peanut consumers’ safety and boost international trade.

  14. Risk Assessment on Dietary Exposure to Aflatoxin B₁ in Post-Harvest Peanuts in the Yangtze River Ecological Region.

    Ding, Xiaoxia; Wu, Linxia; Li, Peiwu; Zhang, Zhaowei; Zhou, Haiyan; Bai, Yizhen; Chen, Xiaomei; Jiang, Jun

    2015-10-01

    Based on the 2983 peanut samples from 122 counties in six provinces of China's Yangtze River ecological region collected between 2009-2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods. Average climatic conditions in the Yangtze River ecological region were calculated based on the data from 118 weather stations via the Thiessen polygon method. The survey results found that the aflatoxin contamination of peanuts was significantly high in 2013. The determination coefficient (R²) of multiple regression reflected by the aflatoxin B₁ content with average precipitation and mean temperature in different periods showed that climatic conditions one month before harvest had the strongest impact on aflatoxin B₁ contamination, and that Hunan and Jiangxi provinces were greatly influenced. The simulated mean aflatoxin B₁ intake from peanuts at the mean peanut consumption level was 0.777-0.790 and 0.343-0.349 ng/(kg·d) for children aged 2-6 and standard adults respectively. Moreover, the evaluated cancer risks were 0.024 and 0.011/(100,000 persons·year) respectively, generally less than China's current liver cancer incidence of 24.6 cases/(100,000 persons·year). In general, the dietary risk caused by peanut production and harvest was low. Further studies would focus on the impacts of peanut circulation and storage on aflatoxin B₁ contamination risk assessment in order to protect peanut consumers' safety and boost international trade. PMID:26501322

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

    Gemma Monyarch

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

  16. Acute systemic exposure to silver-based nanoparticles induces hepatotoxicity and NLRP3-dependent inflammation.

    Ramadi, Khalil B; Mohamed, Yassir A; Al-Sbiei, Ashraf; Almarzooqi, Saeeda; Bashir, Ghada; Al Dhanhani, Aisha; Sarawathiamma, Dhanya; Qadri, Shahnaz; Yasin, Javed; Nemmar, Abderrahim; Fernandez-Cabezudo, Maria J; Haik, Yousef; Al-Ramadi, Basel K

    2016-10-01

    Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1-20 mg/kg), on the early acute (4-24 h post-exposure) and late phase response (96 h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2 mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24 h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24 h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP. PMID:26956548

  17. Macronutrient composition determines accumulation of persistent organic pollutants from dietary exposure in adipose tissue of mice

    Myrmel, Lene Secher; Fjære, Even; Midtbø, Lisa Kolden;

    2016-01-01

    Accumulation of persistent organic pollutants (POPs) has been linked to adipose tissue expansion. As different nutrients modulate adipose tissue development, we investigated the influence of dietary composition on POP accumulation, obesity development and related disorders. Lifespan was determined...... in mice fed fish-oil-based high fat diets during a long-term feeding trial and accumulation of POPs was measured after 3, 6 and 18months of feeding. Further, we performed dose-response experiments using four abundant POPs found in marine sources, PCB-153, PCB-138, PCB-118 and pp'-DDE as single...

  18. Effects of exposure time and dietary ochratoxin A level on broiler performance

    Nedeljković-Trailović Jelena; Jovanović N.; Sinovec Zlatan J.

    2004-01-01

    The present study was designed to examine the harmful effects of low level ochratoxin A (OTA) for different period and different dietary OTA levels for same period of ingestion as well as to assess the resting period necessary to revoke any adverse effects of OTA. The trial was performed on 72 day-old chickens with 12 broilers in each group. The experimental groups were offered feed contaminated with 0.5 ppm OA during 7, 14 or 21 days in the first evaluation, and feed contaminated with 0.5, 1...

  19. Statement on a refined dietary exposure assessment of erythritol (E 968 taking into account additional data provided

    EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS

    2013-03-01

    Full Text Available Following a request by the European Commission, the Scientific Panel on Food Additives and Nutrient Sources added to Foods (ANS carried out an assessment of the dietary exposure to erythritol and concluded on the safety of the proposed use in beverages at a maximum use level of 2.5 %, taking into account additional exposure data provided to the Panel. Anticipated exposure to erythritol from its use as food additive including soft-drinks containing a mean concentration of 2.5 % erythritol would be in the range of 0.004-0.04 g/kg bw/day for toddlers, 0-0.05 g/kg bw/day for children, 0-0.08 g/kg bw/day for adolescents, 0-0.14 g/kg bw/day for adults, and 0-0.01 g/kg bw/day for the elderly. At high level, exposure estimates would be in the range of 0.29-0.48 g/kg bw/day (toddlers, 0.13-0.76 g/kg bw/day (children, 0.04-0.50 g/kg bw/day (adolescents, 0.05-0.43 g/kg bw/day (adults, and 0.01-0.25 g/kg bw/day (the elderly. The main categories contributing to the exposure to erythritol were table-top sweeteners and soft drinks for all age groups except toddlers where soft drinks were the only main contributor. The Panel concluded that based on the new data provided on use levels of erythritol in foods and on the basis of the extension of the authorisation for the use of erythritol to soft drinks at a use level of 2.5 % the Margin of Safety of 1.54 is too low to protect children adequately.

  20. Effects of mother's dietary exposure to acesulfame-K in Pregnancy or lactation on the adult offspring's sweet preference.

    Zhang, Gen-Hua; Chen, Meng-Ling; Liu, Si-Si; Zhan, Yue-Hua; Quan, Ying; Qin, Yu-Mei; Deng, Shao-Ping

    2011-11-01

    This study investigates whether mother's exposure to the artificial sweetener acesulfame-K (AK) during pregnancy or lactation affected her adult offspring's sweet preference. It was found that mother's dietary exposure to AK in pregnancy or lactation decreased the preference thresholds for AK and sucrose solutions in the adult offspring, whereas the preference pattern and the most preferred concentration for AK or sucrose solution were unchanged. Furthermore, the preference scores in the exposure groups were increased significantly when compared with the control group at a range of concentrations for AK or sucrose solution. The existence of AK and its dynamic changes within 24 h in amniotic fluid during pregnancy or in mother's milk during lactation after a single oral infusion of AK solution were revealed by the methods of reversed-phase high-performance liquid chromatography and mass spectrometry. Our data suggest that AK can be ingested by the prenatal or postnatal mice through their mother's amniotic fluid or breast milk, producing a long-dated function on the adult's sweet preference. PMID:21653241

  1. Dietary exposure assessment of pregnant women to bisphenol-A from cans and microwave containers in Southern Spain.

    Mariscal-Arcas, M; Rivas, A; Granada, A; Monteagudo, C; Murcia, M A; Olea-Serrano, F

    2009-02-01

    Bisphenol-A (BPA), material for polycarbonate and epoxy resin synthesis, has been detected in canned food, among other food containers. In mammal studies, BPA transferred from mother to fetus, caused abnormality of reproductive organs, and advanced female puberty. BPA from canned food and microwave containers was analyzed using high performance liquid chromatography and gas chromatography-mass spectrometry. Population was cohort of mother-son pairs established at Granada University Hospital. Frequency of food consumption (including canned food) was studied with a semi-quantitative questionnaire. The most frequently consumed products were fish and juice cans, consumed 1-3 times/week by 34.7% and 22.3% of the study population, respectively. The women made little use of polymer microwave containers, 52.8% never using them and 45.9% using them BPA was 1.1(0.839) microgram/day. No relationship was found between BPA exposure and maternal socio-demographic variables or newborn characteristics. This study offers the first estimate of BPA dietary intake by pregnant women in Southern Spain. The consumption of canned foods and drinks by these women means that their exposure was lower than EFSA estimates for the European population. Nevertheless it remains of concern, given the proven undesirable effects of low-level exposure and higher susceptibility of pregnant women. PMID:19121362

  2. Dietary exposure to trace elements and radionuclides: the methodology of the Italian total diet study 2012-2014

    Marilena D'Amato

    2013-09-01

    Full Text Available This article presents the methodology of the Italian Total Diet Study 2012-2014 aimed at assessing the dietary exposure of the general Italian population to selected non-essential trace elements (Al, inorganic As, Cd, Pb, methyl-Hg, inorganic Hg, U and radionuclides (40K, 134Cs, 137Cs, 90Sr. The establishment of the TDS food list, the design of the sampling plan, and details about the collection of food samples, their standardized culinary treatment, pooling into analytical samples and subsequent sample treatment are described. Analytical techniques and quality assurance are discussed, with emphasis on the need for speciation data and for minimizing the percentage of left-censored data so as to reduce uncertainties in exposure assessment. Finally the methodology for estimating the exposure of the general population and of population subgroups according to age (children, teenagers, adults, and the elderly and gender, both at the national level and for each of the four main geographical areas of Italy, is presented.

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

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

    2016-06-01

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

  4. Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity

    Bert J. M. van de Heijning

    2015-07-01

    Full Text Available Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control. A 50%–75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed.

  5. Possibilities for exposure reduction in computed tomography examination of acute chest pain

    Electrocardiogram-gated (ECG) computed tomography (CT) investigations can be accompanied by high amounts of radiation exposure. This is particularly true for the investigation of patients with unclear and acute chest pain. The common approach in patients with acute chest pain is standard spiral CT of the chest. The chest pain or triple-rule-out CT protocol is a relatively new ECG-gated protocol of the entire chest. This article reviews and discusses different techniques for the CT investigation of patients with acute chest pain. By applying the appropriate scan technique, the radiation exposure for an ECG-gated protocol must not necessarily be higher than a standard chest CT scan Aortic pathologies are far better depicted by ECG-gated scan protocols and depending on the heart rate coronary artery disease can also be detected at the same time. The use of ECG-triggered scans will not support the diagnostics of the pulmonary arteries. However, in unspecific chest pain an ECG-triggered scan protocol can provide information on the differential diagnosis. (orig.)

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

    Reichwaldt, Elke S; Stone, Daniel; Barrington, Dani J; Sinang, Som C; Ghadouani, Anas

    2016-01-01

    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. PMID:27589798

  7. Associations between Chronic Community Noise Exposure and Blood Pressure at Rest and during Acute Noise and Non-Noise Stressors among Urban School Children in India

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

    2010-01-01

    The present study builds on prior research that has examined the association between children’s chronic exposure to community noise and resting blood pressure and blood pressure dysregulation during exposure to acute stressors. A novel contribution of the study is that it examines how chronic noise exposure relates to blood pressure responses during exposure to both noise and non-noise acute stressors. The acute noise stressor was recorded street noise and the non-noise stressor was mental ar...

  8. Discovery of Food Exposure Markers in Urine and Evaluation of Dietary Compliance by Untargeted LC-MS Metabolomics

    Andersen, Maj-Britt Schmidt

    . Biomarkers measured in biological samples are objective measures and therefore advantageous to determine what a person has consumed. Unfortunately, only few well evidenced biomarkers are commonly applied in nutrition studies. Therefore, there is a need to find new biomarkers, in particular for intake of...... individual foods. In this thesis, untargeted metabolomics, a relatively new method within nutrition research, has been applied to find new potential food exposure markers in urine for intake of a range of foods. In addition, it has been investigated, if it is possible to distinguish two dietary patterns, a...... New Nordic Diet (NND) and an Average Danish Diet (ADD), in urine samples from a controlled intervention study. Data from three studies are included in the thesis: A cross-over meal study with nine different meals, a range of small meal studies with individual foods and a six month parallel...

  9. Nasopharyngeal carcinoma in Malaysian Chinese: salted fish and other dietary exposures.

    Armstrong, R W; Imrey, P B; Lye, M S; Armstrong, M J; Yu, M C; Sani, S

    1998-07-17

    We interviewed 282 histologically confirmed cases of nasopharyngeal carcinoma (NPC) in Chinese residents of Selangor and the Federal Territory, Malaysia, and an equal number of Chinese age-, sex-, and length-of-residence-matched controls sampled from the general population. Consumption of 55 dietary items during childhood, and 5 years pre-diagnosis of NPC, was analyzed by univariate and multivariate methods. Four salted preserved foods (fish, leafy vegetables, egg and root), fresh pork/beef organ meats and beer and liquor consumption exhibited strong positive associations, and 4 vegetable/fruit combinations strong negative associations with NPC. Factor analysis and multivariable modeling using estimated factor scores strongly supported separate effects on NPC of vegetables/fruits, salted preserved foods, pork/beef organ meats and beer/liquor consumption. Multivariable modeling associated NPC most clearly with high consumption of salted fish, salted eggs, pork/beef liver and beer and low consumption of Chinese flowering cabbage, oranges/tangerines and shrimp. A strong residual association of social class with NPC remained after adjustment for diet, which is consistent with a substantial role for non-dietary environmental factors. PMID:9650558

  10. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus)

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    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...

  11. The use of a sweetener substitution method to predict dietary exposures for the intense sweetener rebaudioside A.

    Renwick, A G

    2008-07-01

    There are more published dietary exposure data for intense sweeteners than for any other group of food additives. Data are available for countries with different patterns of sweetener approvals and also for population groups with high potential intakes, such as children and diabetic subjects. These data provide a secure basis for predicting the potential intakes of a novel intense sweetener by adjustment of the reported intakes of different sweeteners in mg/kg body weight by their relative sweetness intensities. This approach allows the possibility that a novel sweetener attains the same pattern and extent of use as the existing sweeteners. The intakes by high consumers of other sweeteners allows for possible brand loyalty to the novel sweetener. Using this method, the estimated dietary exposures for rebaudioside A in average and high consumers are predicted to be 1.3 and 3.4mg/kg body weight per day for the general population, 2.1 and 5.0mg/kg body weight per day for children and 3.4 and 4.5mg/kg body weight per day for children with diabetes. The temporary ADI defined by the JECFA for steviol glycosides [JECFA, 2005. Steviol glycosides. In: 63rd Meeting of the Joint FAO/WHO Expert Committee on Food Additives. World Health Organization (WHO), Geneva, Switzerland, WHO Technical Report Series 928, pp. 34-39] was set at 0-2mg/kg body weight (expressed as steviol equivalents); after correction for the difference in molecular weights, these estimated intakes of rebaudioside A are equivalent to daily steviol intakes of less than 2mg/kg. In consequence, this analysis shows that the intakes of rebaudioside A would not exceed the JECFA temporary ADI set for steviol glycosides. PMID:18547702

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

    Respiratory toxicity and lung injury following inhalation exposure to chemical warfare nerve agent soman was examined in guinea pigs without therapeutics to improve survival. A microinstillation inhalation exposure technique that aerosolizes the agent in the trachea was used to administer soman to anesthetized age and weight matched male guinea pigs. Animals were exposed to 280, 561, 841, and 1121 mg/m3 concentrations of soman for 4 min. Survival data showed that all saline controls and animals exposed to 280 and 561 mg/m3 soman survived, while animals exposed to 841, and 1121 mg/m3 resulted in 38% and 13% survival, respectively. The microinstillation inhalation exposure LCt50 for soman determined by probit analysis was 827.2 mg/m3. A majority of the animals that died at 1121 mg/m3 developed seizures and died within 15-30 min post-exposure. There was a dose-dependent decrease in pulse rate and blood oxygen saturation of animals exposed to soman at 5-6.5 min post-exposure. Body weight loss increased with the dose of soman exposure. Bronchoalveolar lavage (BAL) fluid and blood acetylcholinesterase and butyrylcholinesterase activity was inhibited dose-dependently in soman treated groups at 24 h. BAL cells showed a dose-dependent increase in cell death and total cell counts following soman exposure. Edema by wet/dry weight ratio of the accessory lung lobe and trachea was increased slightly in soman exposed animals. An increase in total bronchoalveolar lavage fluid protein was observed in soman exposed animals at all doses. Differential cell counts of BAL and blood showed an increase in total lymphocyte counts and percentage of neutrophils. These results indicate that microinstillation inhalation exposure to soman causes respiratory toxicity and acute lung injury in guinea pigs.

  13. Sleep quality changes in insomniacs and non-insomniacs after acute altitude exposure and its relationship with acute mountain sickness

    Tang XG

    2014-07-01

    Full Text Available Xu-gang Tang,1 Ji-hang Zhang,1 Xu-bin Gao,1 Qian-ning Li,2 Jia-bei Li,1 Jie Yu1 Jun Qin,1 Lan Huang11Institute of Cardiovascular Diseases, 2Department of Neurology, Xinqiao Hospital, Third Military Medical University, Chongqing, People’s Republic of ChinaObjective: We aimed to observe the changes in subjective sleep quality among insomniacs and non-insomniacs after acute ascending to 3,700 m and its possible relationship with acute mountain sickness (AMS. Methods: A total of 600 adult men were recruited. Subjects’ subjective sleep quality was evaluated by the Athens Insomnia Scale. AMS was assessed using the Lake Louise scoring system. Arterial oxygen saturation was measured. Results: Despite insomnia resolution in only a few subjects, the prevalence of insomnia among insomniacs remained stable at 90% after rapid ascent to 3,700 m. However, among non-insomniacs, the prevalence of insomnia sharply increased to 32.13% in the first day of altitude exposure and progressively reduced to 4.26% by the 60th day of altitude stay. Moreover, the prevalences of insomnia symptoms decreased more markedly from day 1 to day 60 at 3,700 m among non-insomniacs than among insomniacs. At 3,700 m, the prevalence of AMS among insomniacs was 79.01%, 60.49%, and 32.10% on the first, third, and seventh days, respectively, which was significantly higher than that among non-insomniacs. Multivariate regression revealed that elevated Athens Insomnia Scale scores are an independent risk factor for AMS (adjusted odds ratio 1.388, 95% confidence interval: 1.314–1.464, P<0.001, whereas high arterial oxygen saturation and long duration of altitude exposure are protective factors against AMS. Conclusion: Our results suggest that the effect of high-altitude exposure on subjective sleep quality is more marked, but disappears more quickly, among non-insomniacs than among insomniacs, whereas AMS is especially common among insomniacs. Moreover, poor subjective sleep

  14. Association of bisphenol A exposure with dietary quality indices in Spanish schoolchildren.

    Rivas, Ana; Monteagudo, Celia; Heras-Gonzalez, Leticia; Mariscal-Arcas, Miguel; Lorenzo-Tovar, Maria Luisa; Olea-Serrano, Fátima

    2016-08-01

    Young children, whose growth and development are highly dependent on the endocrine system, are particularly vulnerable to endocrine disruptor exposure. The main objectives of this study were to measure BPA migration levels from cans, fruit juice bottles/packs, and microwave containers used for food/drinks consumed by a sample of 6- to 8-year old schoolchildren in Spain and to estimate the relationship between their resulting BPA exposure and diet quality index scores (Mediterranean Diet Score and Breakfast Quality Index). The mean BPA concentration was 11.8 ng/mL for vegetable cans, 22.1 ng/mL for pulse cans, 3.6 ng/mL for juice bottles/packs, and 1.2 ng/mL for microwave containers. Results revealed a significant association between the Mediterranean Diet Score and low BPA exposure of the children. BPA exposure below the median level was significantly associated with a higher score in both the first-grade (P = 0.030) and second-grade (p = 0.0001) groups. However, no association was found between BPA exposure and the Breakfast Quality Index. In conclusion, children with a stronger adherence to a Mediterranean-like diet appear to be less exposed to BPA migrating from food packaging and microwave containers. Further research is warranted on the inadvertent exposure of children to endocrinedisrupting chemicals from these sources. PMID:27208728

  15. Medical management of severe local radiation injury after acute X-ray exposure

    Medical management during acute period in a case of severe local radiation injury after acute X-ray exposure includes 3 stages. During the fist stage patient got conservative treatment according to the common pathogenetic mechanisms of LRI (dis aggregating therapy, stimulation of regeneration, dis intoxication therapy, antibiotic therapy, pain relief therapy, Local anti-burn therapy-specific non-adhesive bandage with antiseptic and anti-burn medicaments); estimation of severity, deepness and area of injury by clinical picture and dates of instrumental methods of examining; defining necessity and volume of surgical treatment; preparing arrangements for surgical treatment. This stage ends with forming of demarcation line of a very hard severity of a Local Radiation Injure. The second stage includes necrectomy of the area of a very hard severity with microsurgical plastic by re vascularized flap and auto dermoplastic. The third stage - adaptation of re vascularized flap and total epithelization of injured area. (author)

  16. Acute Exposure to Crystalline Silica Reduces Macrophage Activation in Response to Bacterial Lipoproteins.

    Beamer, Gillian L; Seaver, Benjamin P; Jessop, Forrest; Shepherd, David M; Beamer, Celine A

    2016-01-01

    Numerous studies have examined the relationship between alveolar macrophages (AMs) and crystalline silica (SiO2) using in vitro and in vivo immunotoxicity models; however, exactly how exposure to SiO2 alters the functionality of AM and the potential consequences for immunity to respiratory pathogens remains largely unknown. Because recognition and clearance of inhaled particulates and microbes are largely mediated by pattern recognition receptors (PRRs) on the surface of AM, we hypothesized that exposure to SiO2 limits the ability of AM to respond to bacterial challenge by altering PRR expression. Alveolar and bone marrow-derived macrophages downregulate TLR2 expression following acute SiO2 exposure (e.g., 4 h). Interestingly, these responses were dependent on interactions between SiO2 and the class A scavenger receptor CD204, but not MARCO. Furthermore, SiO2 exposure decreased uptake of fluorescently labeled Pam2CSK4 and Pam3CSK4, resulting in reduced secretion of IL-1β, but not IL-6. Collectively, our data suggest that SiO2 exposure alters AM phenotype, which in turn affects their ability to uptake and respond to bacterial lipoproteins. PMID:26913035

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

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

    2011-01-01

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

  18. Proteomic analysis of matrix of dental biofilm formed under dietary carbohydrate exposure.

    Moi, G P; Cury, J A; Dombroski, T C D; Pauletti, B A; Paes Leme, A F

    2012-01-01

    To evaluate whether protein changes in extracellular matrix of dental biofilm are a unique property of sucrose, this in situ study was conducted using as active control glucose and fructose, the sucrose monosaccharide constituents. Proteins were analyzed by two-dimensional electrophoresis followed by LC-MS/MS after trypsin digestion. Absence or lower abundance of calcium-binding proteins and higher abundance of prolactin-induced proteins were found in biofilm formed in the presence of sucrose or its monosaccharide constituents compared with water, the negative control group. The data suggest that besides sucrose, other dietary carbohydrates may also provoke a change in the protein profile of extracellular matrix of dental biofilm formed. PMID:22614073

  19. Reproductive performance of Bracon hebetor females following acute exposure to sulphur dioxide in air

    Petters, R.M.; Mettus, R.V.

    1982-02-01

    Bracon hebetor females were exposed to 3 ppm SO/sub 2/ for 3 h and 5 h and their reproductive performance was assayed for 20 days. Lifespan of the treated females and their egg production were not different from those of control wasps. Also, egg hatchability, an important indicator of fertility, was not consistently affected. These results indicate Bracon reproductive performance, a sensitive toxicological assay system, to be resistant to acute SO/sub 2/ exposure. Putative SO/sub 2/ effects on parasitic wasp populations in nature are therefore probably not due to interference with female fecundity and fertility.

  20. Rhabdomyolysis, acute kidney injury and transverse myelitis due to naive heroin exposure

    Ankur Gupta

    2011-01-01

    Full Text Available Heroin exposure can cause various complications like seizures, stroke, spongiform encephalopathy, transverse myelopathy, plexopathy, compartment syndrome, rhabdomyolysis and renal failure due to various mechanisms. We report here a young male who smoked heroin for the first time and developed transverse myelitis, rhabdomyolysis and acute kidney injury requiring dialysis. His renal recovery was complete by four weeks, while neurological improvement occurred 8 to 12 weeks later. This case suggests a common pathogenic mechanism of heroin intoxication involving multiple systems of the body.

  1. The Role of Dietary Management in the Reoccurrence of Acute Pancreatitis%饮食管理在急性胰腺炎复发中的作用

    杨绪兰; 张树荣; 罗莉; 余友敏; 赵小晶

    2015-01-01

    Objective To explore the impact of dietary management on the reoccurrence in discharged patients with acute pancreati-tis. Methods Dietary management was performed to 489 cases with acute pancreatitis, who were divided into 2 groups:research group including 281 cases obeying dietary management after discharge and control group including 208 cases disobeying dietary management after discharge;the reoccurrence of acute pancreatitis in the 2 groups was comparatively analyzed. Results The reoccurrence in research group was 8.9%, much lower than that in control group (15.4%), there existed a statistical difference between the 2 groups (P<0.05);out of the cases of reoccurrence in control group, 22 cases (68.8%) had improper diet before reoccurrence. Conclusions Dietary manage-ment by professional nutritionist in cases with acute pancreatitis after discharge can reduce the reoccurrence, which may be even lower in cases obeying dietary management.%目的:探讨急性胰腺炎患者出院后饮食管理对急性胰腺炎复发的影响。方法对489例急性胰腺炎患者进行营养管理,将患者按其出院后是否遵从饮食管理分为两组:研究组281例,为出院后遵从饮食管理者;对照组208例,为出院后不遵从饮食管理者。比较两组急性胰腺炎患者的复发情况。结果研究组急性胰腺炎患者复发率为8.9%,对照组为15.4%,两组比较P<0.05,研究组显著低于对照组;对照组复发患者中,22例(68.8%)复发前有不当饮食。结论专业营养师对出院的急性胰腺炎患者进行饮食管理可减少本病的复发,对饮食管理依从性较好者复发率更低。

  2. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus).

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    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. PMID:27382568

  3. Toxicokinetics of chloral hydrate in ad libitum-fed, dietary-controlled, and calorically restricted male B6C3F1 mice following short-term exposure

    Chloral hydrate is widely used as a sedative in pediatric medicine and is a by-product of water chlorination and a metabolic intermediate in the biotransformation of trichloroethylene. Chloral hydrate and its major metabolite, trichloroacetic acid, induce liver tumors in B6C3F1 mice, a strain that can exhibit high rates of background liver tumor incidence, which is associated with increased body weight. This report describes the influence of diet and body weight on the acute toxicity, hepatic enzyme response, and toxickinetics of chloral hydrate as part of a larger study investigating the carcinogenicity of chloral hydrate in ad libitum-fed and dietary controlled mice. Dietary control involves moderate food restriction to maintain the test animals at an idealized body weight. Mice were dosed with chloral hydrate at 0, 50, 100, 250, 500, and 1000 mg/kg daily, 5 days/week, by aqueous gavage for 2 weekly dosing cycles. Three diet groups were used: ad libitum, dietary control, and 40% caloric restriction. Both dietary control and caloric restriction slightly reduced acute toxicity of high doses of chloral hydrate and potentiated the induction of hepatic enzymes associated with peroxisome proliferation. Chloral hydrate toxicokinetics were investigated using blood samples obtained by sequential tail clipping and a microscale gas chromatography technique. It was rapidly cleared from serum within 3 h of dosing. Trichloroacetate was the major metabolite in serum in all three diet groups. Although the area under the curve values for serum trichloroacetate were slightly greater in the dietary controlled and calorically restricted groups than in the ad libitum-fed groups, this increase did not appear to completely account for the potentiation of hepatic enzyme induction by dietary restriction

  4. Dietary acrylamide exposure among Finnish adults and children: The potential effect of reduction measures

    Hirvonen, Tero; Jestoi, Marika; Tapanainen, Heli; Valsta, Liisa; Virtanen, Suvi M; Sinkko, Harri; Kronberg-Kippilä, Carina; Kontto, Jukka; Virtamo, Jarmo; Simell, Olli; Peltonen, Kimmo

    2011-01-01

    Abstract A deterministic exposure assessment using the Nusser method that adjusts for within-subject variation and for nuisance effects among Finnish children and adults was carried out. The food consumption data covered 2,038 adults (25?74 years old) and 1,514 children of one, three, and six years of age, with the data on foods? acrylamide content obtained from published Finnish studies. We found that acrylamide exposure was highest among the three-year-old children (median: 1.01 ...

  5. Genome-wide gene expression profiling of acute metal exposures in male zebrafish

    Christine E. Baer

    2014-12-01

    Full Text Available To capture global responses to metal poisoning and mechanistic insights into metal toxicity, gene expression changes were evaluated in whole adult male zebrafish following acute 24 h high dose exposure to three metals with known human health risks. Male adult zebrafish were exposed to nickel chloride, cobalt chloride or sodium dichromate at concentrations corresponding to their respective 96 h LC20, LC40 and LC60 (i.e. 96 h concentrations at which 20%, 40% and 60% lethality is expected, respectively. Histopathology was performed on a subset of metal-exposed zebrafish to phenotypically anchor transcriptional changes associated with each metal exposure. Here we describe in detail the contents and quality controls for the gene expression and other data associated with the study published by Hussainzada and colleagues in BMC Pharmacology and Toxicology (Hussainzada et al., 2014 with the data uploaded to Gene Expression Omnibus (accession number GSE50648.

  6. Acute Inhalation Exposure to Titanium Ethanolate as a Possible Cause of Metal Fume Fever

    M Ahmadimanesh

    2014-04-01

    Full Text Available Occupational inhalation exposure to noxious agents is not uncommon. Herein, we present a 26-year-old male student who had accidental acute inhalation exposure to a large quantity of titanium ethanolate and hydrogen chloride in chemistry lab. He was referred to the emergency department of our hospital with low-grade fever, dyspnea, headache, fatigue and myalgia. After 24 hrs of symptomatic treatment (oxygen therapy and acetaminophen, the fever was subsided and the patient discharged home in a good clinical condition. The presented symptoms could be interpreted as a form of metal fume fever. It can therefore be concluded that organo-metallic compound of titanium metal may have the potential to produce metal fume fever in human.

  7. Parental Whole Life Cycle Exposure to Dietary Methylmercury in Zebrafish (Danio rerio) Affects the Behavior of Offspring.

    Mora-Zamorano, Francisco X; Klingler, Rebekah; Murphy, Cheryl A; Basu, Niladri; Head, Jessica; Carvan, Michael J

    2016-05-01

    Methylmercury (MeHg) is an established neurotoxicant of concern to fish-eating organisms. While most studies have focused on the fish consumers, much less is known about the effects of MeHg on the fish themselves, especially following exposures to chronic and environmentally relevant scenarios. Here we evaluated the behavioral effects of developmental MeHg insult by exposing parental generations of zebrafish to an environmentally realistic MeHg dietary concentration (1 ppm) and two higher concentrations (3 and 10 ppm) throughout their whole life span. Upon reaching adulthood, their offspring were analyzed through a series of behavioral tests, including the visual-motor response (VMR) assay, analysis of spontaneous swimming and evaluation of foraging efficiency. The VMR assay identified decreased locomotor output in the 6 day postfertilization (dpf) offspring of fish exposed to 3 and 10 ppm MeHg. However, in a second test 7 dpf fish revealed an increase in locomotor activity in all MeHg exposures tested. Increases in locomotion continued to be observed until 16 dpf, which coincided with increased foraging efficiency. These results suggest an association between MeHg and hyperactivity, and imply that fish chronically exposed to MeHg in the wild may be vulnerable to predation. PMID:27023211

  8. Harmonisation of food consumption data format for dietary exposure assessments of chemicals analysed in raw agricultural commodities.

    Boon, Polly E; Ruprich, Jiri; Petersen, Annette; Moussavian, Shahnaz; Debegnach, Francesca; van Klaveren, Jacob D

    2009-12-01

    In this paper, we present an approach to format national food consumption data at raw agricultural commodity (RAC) level. In this way, the data is both formatted in a harmonised way given the comparability of RACs between countries, and suitable to assess the dietary exposure to chemicals analysed in RACs at a European level. In this approach, consumption data needs to be converted to edible part of RAC (e-RAC) level using a RAC conversion database. To subsequently use this data in exposure assessments, both e-RACs and RACs analysed in chemical control programmes should be classified via a uniform system. Furthermore, chemical concentrations in RACs may need to be converted to e-RAC level using processing factors. To illustrate the use of this approach, we describe how the Dutch RAC conversion database was used to convert consumption data of four national consumption surveys to e-RAC level, and the use of the FAO/WHO Codex Classification system of Foods and Animal Feeds to harmonise the classification. We demonstrate that this approach works well for pesticides and glycoalkaloids, and is an essential step forward in the harmonisation of risk assessment procedures within Europe when addressing chemicals analysed in RACs by all national food control systems. PMID:19682531

  9. Dietary exposure of Brazilian consumers to dithiocarbamate pesticides : a probabilistic approach

    Caldas, E.D.; Tressou, J.; Boon, P.E.

    2006-01-01

    A probabilistic estimation of the exposure of the Brazilian population to the dithiocarbamate pesticides was performed using the Monte Carlo Risk Assessment program (MCRA 3.5). Residue data, as CS(2), for 3821 samples were obtained from the Brazilian national monitoring program on pesticide residues

  10. Dietary nucleotide and nucleoside exposure in infancy and atopic dermatitis, recurrent wheeze, and allergic sensitization

    Timmermans, M.J.C.; Dagnelie, P.C.; Theunisz, E.H.; Ewalds, D.; Thijs, C.; Mommers, M.; Arts, I.C.

    2015-01-01

    We hypothesized that early life exposure to nucleotides and nucleosides lowers the risk of recurrent wheeze, atopic dermatitis, and allergic sensitization among n = 429 children. Concentrations in breast milk were established by high-performance liquid chromatography; concentrations in formula milks

  11. High-Throughput Dietary Exposure Predictions for Chemical Migrants from Food Packaging Materials

    United States Environmental Protection Agency researchers have developed a Stochastic Human Exposure and Dose Simulation High -Throughput (SHEDS-HT) model for use in prioritization of chemicals under the ExpoCast program. In this research, new methods were implemented in SHEDS-HT...

  12. Assessment of dietary background exposure of the Irish adult population to dioxins and PCBs particularly taking into account additional exposure due to the 2008 Irish dioxin food contamination incident

    Tlustos, Christina L. T.

    2014-01-01

    Irish monitoring data on PCDD/Fs, DL-PCBs and Marker PCBs were collated and combined with Irish Adult Food Consumption Data, to estimate dietary background exposure of Irish adults to dioxins and PCBs. Furthermore, all available information on the 2008 Irish pork dioxin food contamination incident was collated and analysed with a view to evaluate any potential impact the incident may have had on general dioxin and PCB background exposure levels estimated for the adult population in Ireland. T...

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

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

    2015-08-01

    Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. PMID:24194397

  14. Modulation of pulmonary defense mechanisms by acute exposures to nitrogen dioxide

    The effect of acute exposures to NO2 on the antibacterial defenses of the murine lung was assessed following inhalation challenges with Staphylococcus aureus, Proteus mirabilis, and Pasteurella pneumotropica. With S. aureus pulmonary antibacterial defenses were suppressed at NO2 levels of 4.0 ppm and greater. Exposure to 10.0 ppm enhanced the intrapulmonary killing of P. mirabilis which correlated with an increase in the phagocytic cell populations lavaged from the lungs; at 20.0 ppm bactericidal activity against P. mirabilis was impaired. Pulmonary antibacterial defenses against P. pneumotropica were impaired at 10.0 ppm which correlated with a decrease in the retrieved phagocytic lung cell population. Reversing the order of treatment (ie., NO2 exposure prior to bacterial challenge) raised the threshold concentration for NO2-induced impairment of intrapulmonary bacterial killing. With S. aureus the effect was not observed at 5.0 ppm but at 10.0 ppm and with P. mirabilis not at 20.0 ppm but at 30.0 ppm intrapulmonary killing was enhanced. Exposures up to 20.0 ppm of NO2 did not effect the physical translocation mechanisms of the lung as quantitated by declines in pulmonary radiotracer activity following aerogenic challenge with 32P-labeled staphylococci

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

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

    2016-01-01

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

  16. Age dependent values of dietary intake for assessing human exposures to environmental pollutants

    Detailed information concerning human food consumption patterns necessary for relating pollutant body burdens to environmental contamination levels was compiled to be used in lieu of site-specific data for calculating health impacts arising from the ingestion of food containing various levels of such pollutants as radionuclides, toxic heavy metals, insecticides and many others. This paper examines available data on human food consumption rates and estimates dietary intake rates by individuals of various ages. Ingestion parameters include intake rates of water and other beverages, milk, vegetables, fruits, meat, poultry, grain and fish. Information was analyzed from documented surveys of individuals within households and from interviews and personal communications. Although average intake rates are often the only data reported in the literature, ranges as well as averages are included in this paper whenever possible. Various results are tabulated including per capita food consumption in 1955 and 1965 and changes in per capita consumption as well as changes by urbanization. Details of milk consumption are presented by selected sex-age groups. Solid food intake is given by age group. Market basket quantities of foods consumed daily are also tabulated. (author)

  17. Assessment of dietary exposure to trace metals in Baffin Inuit food.

    Chan, H. M.; Kim, C.; Khoday, K; Receveur, O.; Kuhnlein, H V

    1995-01-01

    Chronic metal toxicity is a concern in the Canadian Arctic because of the findings of high metal levels in wildlife animals and the fact that traditional food constitutes a major component of the diet of indigenous peoples. We examined exposure to trace metals through traditional food resources for Inuit living in the community of Qikiqtarjuaq on Baffin Island in the eastern Arctic. Mercury, cadmium, and lead were determined in local food resources as normally prepared and eaten. Elevated con...

  18. Estimated Dietary Exposure to Mycotoxins after Taking into Account the Cooking of Staple Foods in Japan

    Shiro Saito

    2013-05-01

    Full Text Available Mycotoxins are commonly present in cereal grains and are not completely destroyed during their cooking and processing. When mycotoxins contaminate staple foods, the risk for exposure becomes serious. In East Asia, including Japan, rice is consumed as a staple food, and with the increasingly Westernized lifestyle, the consumption of wheat has increased. The mycotoxins commonly associated with rice and wheat are total aflatoxin (AFL and ochratoxin A (OTA, respectively. This study examined the retention of AFL and OTA during the cooking of rice and pasta. AFL was retained at 83%–89% the initial level after the cooking of steamed rice. In pasta noodles, more than 60% of the OTA was retained. These results show that AFL and OTA are relatively stable during the cooking process, suggesting that a major reduction in the exposure to these mycotoxins cannot be expected to occur by cooking rice and pasta. The estimated exposure assessment at the high consumer level (95th percentile and the mycotoxin contamination level determined by taking into account these reductions in the present study should be useful for the establishment of practical regulations for mycotoxins in staple foods.

  19. Effects of maternal dietary exposure to cadmium during pregnancy on mammary cancer risk among female offspring

    Jennifer Davis

    2013-01-01

    Full Text Available Background: Since heavy metal cadmium is an endocrine disrupting chemical, we investigated whether maternal exposure to cadmium during the pregnancy alters mammary tumorigenesis among female offspring. Methods: From gestation day 10 to day 19, pregnant rat dams were fed modified American Institute of Nutrition (AIN93G diet containing 39% energy from fat (baseline diet, or the baseline diet containing moderate (75 μg/kg of feed or high (150 μg/kg cadmium levels. Some dams were injected with 10 μg 17β-estradiol (E2 daily between gestation days 10 and 19. Results: Rats exposed to a moderate cadmium dose in utero were heavier and exhibited accelerated puberty onset. Both moderate and high cadmium dose led to increased circulating testosterone levels and reduced the expression of androgen receptor in the mammary gland. The moderate cadmium dose mimicked the effects of in utero E2 exposure on mammary gland morphology and increased both the number of terminal end buds and pre-malignant hyperplastic alveolar nodules (HANs, but in contrast to the E2, it did not increase 7, 12-dimethylbenz (a anthracene-induced mammary tumorigenesis. Conclusions: The effects of in utero cadmium exposure were dependent on the dose given to pregnant dams: Moderate, but not high, cadmium dose mimicked some of the effects seen in the in utero E2 exposed rats, such as increased HANs in the mammary gland.

  20. Acute Dietary Nitrate Supplementation and Exercise Performance in COPD: A Double-Blind, Placebo-Controlled, Randomised Controlled Pilot Study

    Curtis, Katrina J.; O’Brien, Katie A.; Tanner, Rebecca J.; Polkey, Juliet I.; Minnion, Magdalena; Feelisch, Martin; Polkey, Michael I.; Edwards, Lindsay M.; Hopkinson, Nicholas S.

    2015-01-01

    Background Dietary nitrate supplementation can enhance exercise performance in healthy people, but it is not clear if it is beneficial in COPD. We investigated the hypotheses that acute nitrate dosing would improve exercise performance and reduce the oxygen cost of submaximal exercise in people with COPD. Methods We performed a double-blind, placebo-controlled, cross-over single dose study. Subjects were randomised to consume either nitrate-rich beetroot juice (containing 12.9mmoles nitrate) or placebo (nitrate-depleted beetroot juice) 3 hours prior to endurance cycle ergometry, performed at 70% of maximal workload assessed by a prior incremental exercise test. After a minimum washout period of 7 days the protocol was repeated with the crossover beverage. Results 21 subjects successfully completed the study (age 68±7years; BMI 25.2±5.5kg/m2; FEV1 percentage predicted 50.1±21.6%; peak VO2 18.0±5.9ml/min/kg). Resting diastolic blood pressure fell significantly with nitrate supplementation compared to placebo (-7±8mmHg nitrate vs. -1±8mmHg placebo; p = 0.008). Median endurance time did not differ significantly; nitrate 5.65 (3.90–10.40) minutes vs. placebo 6.40 (4.01–9.67) minutes (p = 0.50). However, isotime oxygen consumption (VO2) was lower following nitrate supplementation (16.6±6.0ml/min/kg nitrate vs. 17.2±6.0ml/min/kg placebo; p = 0.043), and consequently nitrate supplementation caused a significant lowering of the amplitude of the VO2-percentage isotime curve. Conclusions Acute administration of oral nitrate did not enhance endurance exercise performance; however the observation that beetroot juice caused reduced oxygen consumption at isotime suggests that further investigation of this treatment approach is warranted, perhaps targeting a more hypoxic phenotype. Trial Registration ISRCTN Registry ISRCTN66099139 PMID:26698120

  1. Acute Dietary Nitrate Supplementation and Exercise Performance in COPD: A Double-Blind, Placebo-Controlled, Randomised Controlled Pilot Study.

    Katrina J Curtis

    Full Text Available Dietary nitrate supplementation can enhance exercise performance in healthy people, but it is not clear if it is beneficial in COPD. We investigated the hypotheses that acute nitrate dosing would improve exercise performance and reduce the oxygen cost of submaximal exercise in people with COPD.We performed a double-blind, placebo-controlled, cross-over single dose study. Subjects were randomised to consume either nitrate-rich beetroot juice (containing 12.9 mmoles nitrate or placebo (nitrate-depleted beetroot juice 3 hours prior to endurance cycle ergometry, performed at 70% of maximal workload assessed by a prior incremental exercise test. After a minimum washout period of 7 days the protocol was repeated with the crossover beverage.21 subjects successfully completed the study (age 68 ± 7 years; BMI 25.2 ± 5.5 kg/m2; FEV1 percentage predicted 50.1 ± 21.6%; peak VO2 18.0 ± 5.9 ml/min/kg. Resting diastolic blood pressure fell significantly with nitrate supplementation compared to placebo (-7 ± 8 mmHg nitrate vs. -1 ± 8 mmHg placebo; p = 0.008. Median endurance time did not differ significantly; nitrate 5.65 (3.90-10.40 minutes vs. placebo 6.40 (4.01-9.67 minutes (p = 0.50. However, isotime oxygen consumption (VO2 was lower following nitrate supplementation (16.6 ± 6.0 ml/min/kg nitrate vs. 17.2 ± 6.0 ml/min/kg placebo; p = 0.043, and consequently nitrate supplementation caused a significant lowering of the amplitude of the VO2-percentage isotime curve.Acute administration of oral nitrate did not enhance endurance exercise performance; however the observation that beetroot juice caused reduced oxygen consumption at isotime suggests that further investigation of this treatment approach is warranted, perhaps targeting a more hypoxic phenotype.ISRCTN Registry ISRCTN66099139.

  2. Adverse health effects due to arsenic exposure: Modification by dietary supplementation of jaggery in mice

    Populations of villages of eastern India and Bangladesh and many other parts of the world are exposed to arsenic mainly through drinking water. Due to non-availability of safe drinking water they are compelled to depend on arsenic-contaminated water. Generally, poverty level is high in those areas and situation is compounded by the lack of proper nutrition. The hypothesis that the deleterious health effects of arsenic can be prevented by modification of dietary factors with the availability of an affordable and indigenous functional food jaggery (sugarcane juice) has been tested in the present study. Jaggery contains polyphenols, vitamin C, carotene and other biologically active components. Arsenic as sodium-m-arsenite at low (0.05 ppm) and high (5 ppm) doses was orally administered to Swiss male albino mice, alone and in combination with jaggery feeding (250 mg/mice), consecutively for 180 days. The serum levels of total antioxidant, glutathione peroxidase and glutathione reductase were substantially reduced in arsenic-exposed groups, while supplementation of jaggery enhanced their levels in combined treatment groups. The serum levels of interleukin-1β, interleukin-6 and TNF-α were significantly increased in arsenic-exposed groups, while in the arsenic-exposed and jaggery supplemented groups their levels were normal. The comet assay in bone marrow cells showed the genotoxic effects of arsenic, whereas combination with jaggery feeding lessened the DNA damage. Histopathologically, the lung of arsenic-exposed mice showed the necrosis and degenerative changes in bronchiolar epithelium with emphysema and thickening of alveolar septa which was effectively antagonized by jaggery feeding. These results demonstrate that jaggery, a natural functional food, effectively antagonizes many of the adverse effects of arsenic.

  3. In vivo proliferation of bone marrow stem cells of mice after combined long-term exposure to gamma radiation and acute exposure to X rays

    The aim of this paper was to ascertain whether a long-term exposure to gamma radiation at low dose rates, comparable to the professional permissible dose, can modify the response of bone marrow stem cells to single acute irradiation. The study was carried out by the method of exogenous spleen colonization. Continuous exposure to Co60 gamma rays was applied at dose rates of 0,223 mGy x h-1 and 1,25 mGy x h-1. The duration of exposure was 30-105 days, accumulated doses within this time were 0.16-0,56 Gy respectively. After the exposure was completed the mice were subjected to acute X-rays irradiation at the doses of 0,5-4,0 Gy. It was found the bone marrow stem cells, capable to form clones in the spleens, respond to the dose effect as well as at very low its values. The effect estimated by changed responsiveness to acute irradiation depends to accumulated dose only. The higher is the accumulated dose during long-term irradiation the greater is diminishing of repopulating ability of bone marrow cells after following acute irradiation. 4 refs., 3 figs., 1 tab. (author)

  4. Acute and long-term effects of exposure to sodium monofluoroacetate (1080 in sheep

    S. R. Gooneratne

    2008-08-01

    Full Text Available Acute and long-term effects of a single, relative lyhigh oral dose (0.25a nd 0.30 mg/kg of sodium monofluoroacetate (1080 on the survival and productivity of sheep were evaluated to establish a better understanding of 1080 poisoning and identify more specific changes diagnostic of toxicosis. In survivors, clinical signs of acute 1080 toxicosis such as salivation and lethar gywere generally very mild. Fasted animals were more prone to 1080 toxicity. In animals that died, more severe signs, including tachypnoea, dyspnoea, and tremors occurred for 15-20 min prior to death. 1080 concentrations were highest in the blood> heart> skeletal muscle> liver. 1080 could not be detected in any of these organs of the animals that survived. Serum citratec oncentratione were elevated for 4 days after dosing. No clinical or biochemical abnormalities were found in any animal after 4 days. Histopathological lesions were most marked in the heart and lung with inflammation, necrosis, and scattered foci of fibrous tissue in the myocardium, pulmonary oedema and inflammation of the lung. No adverse longterm effects on general health or reproductive performance were observed in any sheep that survived the first 4 days following exposure to 1080. The most reliable diagnostic in dicators of 1080 exposure in sheep were measurement of its residues in blood, skeletal muscle and ruminal contents, increased serum citratec oncentratione; l evated heart rate,and characteristic electrocardiograpchh anges(up to 4 days after exposure. Death from 1080 is most likely to occur within 96 h, and animals that survived this period appeared normal.

  5. Dietary exposure to the PCB mixture aroclor 1254 may compromise osmoregulation by altering central vasopressin release

    Coburn, C.G. [Environmental Toxicology, Univ. of California at Riverside, CA (United States); Gillard, E.; Curras-Collazo, M. [Cell Biology and Neuroscience, Univ. of California at Riverside, CA (United States)

    2004-09-15

    Despite the importance of systemic osmoregulation, the potential deleterious effects of persistent organochlorines, such as polychlorinated biphenyls (PCBs), on body fluid regulation has not been thoroughly investigated. In an effort to ameliorate this deficit, the current study explores the toxic effects of PCBs on osmoregulation, and in particular, on the activity of the magnocellular neuroendocrine cell (MNC) system of the hypothalamus. MNCs of the supraoptic nucleus (SON) release oxytocin (OXY) and vasopressin (VP) from terminals in the neurohypophysis in response to dehydration. The latter is released to effect water conservation in response to dehydration via its action upon the kidney and through extra-renal actions. MNCs also secrete VP from their cell bodies and dendrites locally i.e., into the extracellular space of the SON. Although it has been shown that both intranuclear and systemic release rise in response to dehydration the physiological significance of intranuclear release has not been fully elucidated. We chose to use voluntary ingestion as the route of PCB exposure since it is more reflective of natural exposure compared to ip injection. One unexpected observation that resulted from pilot studies using ip injection of PCBs was the deleterious effects of the vehicle (corn oil) resulting in pooling of lipid within the abdominal cavity, mottling of the liver, fatty liver and general discoloration of all abdominal viscera at time of sacrifice. Therefore, all work described in this series of experiments have employed voluntary ingestion of the toxin. Work described in this paper suggests that PCBs in concentrations reflecting realistic lifetime exposure levels may negatively impact homeostatic mechanisms responsible for body water balance by altering somatodendritic (intranuclear) VP secretion in response to dehydration in vivo. The downstream consequences of such influence is currently under investigation, and preliminary evidence suggests that the

  6. Internal exposure to the population of coastal Karnataka of South India from dietary intake

    Systematic studies on radiation levels and radionuclide distribution in the environment of coastal Karnatak, located on the south west coast of India, was initiated to provide baseline data on background radiation levels for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region. The paper presents the concentration of the prominent natural and artificial radionuclides in vegetarian and non-vegetarian composite diet samples of the region. The internal exposures to the population of the region were estimated from the concentration of prominent radionuclides in total diet. The results are discussed in the light of literature values reported for other environments. (Author)

  7. Parental dietary seleno-L-methionine exposure and resultant offspring developmental toxicity.

    Chernick, Melissa; Ware, Megan; Albright, Elizabeth; Kwok, Kevin W H; Dong, Wu; Zheng, Na; Hinton, David E

    2016-01-01

    Selenium (Se) leaches into water from agricultural soils and from storage sites for coal fly ash. Se toxicity causes population and community level effects in fishes and birds. We used the laboratory aquarium model fish, Japanese medaka (Oryzias latipes), an asynchronous breeder, to determine aspects of uptake in adults and resultant developmental toxicity in their offspring. The superior imaging properties of the model enabled detailed descriptions of phenotypic alterations not commonly reported in the existing Se literature. Adult males and females in treatment groups were exposed, separately and together, to a dry diet spiked with 0, 12.5, 25, or 50 μg/g (dry weight) seleno-L-methionine (SeMet) for 6 days, and their embryo progeny collected for 5 days, maintained under controlled conditions and observed daily for hatchability, mortality and/or developmental toxicity. Sites of alteration included: craniofacial, pericardium and abdomen (Pc/Ab), notochord, gall bladder, spleen, blood, and swim bladder. Next, adult tissue Se concentrations (liver, skeletal muscle, ovary and testis) were determined and compared in treatment groups of bred and unbred individuals. No significant difference was found across treatment groups at the various SeMet concentrations; and, subsequent analysis compared exposed vs. control in each of the treatment groups at 10 dpf. Increased embryo mortality was observed in all treatment groups, compared to controls, and embryos had a decreased hatching rate when both parents were exposed. Exposure resulted in significantly more total altered phenotypes than controls. When altered phenotypes following exposure of both parents were higher than maternal only exposure, a male role was suggested. The comparisons between treatment groups revealed that particular types of phenotypic change may be driven by the sex of the exposed parent. Additionally, breeding reduced Se concentrations in some adult tissues, specifically the liver of exposed females

  8. Improvement of cold resistance and performance of broilers by acute cold exposure during late embryogenesis.

    Shinder, D; Ruzal, M; Giloh, M; Druyan, S; Piestun, Y; Yahav, S

    2011-03-01

    The aim of this study was to fine-tune previous acute cold exposure treatments of broiler embryos during late embryogenesis to improve lifelong cold resistance and performance. Six hundred Cobb hatching eggs were incubated under standard conditions and then exposed to 3 treatments: control; cold treatment in which embryos were exposed to 15°C for 30 min on d 18 and 19 of incubation (30 × 2); and cold treatment similar to 30 × 2 but with 60-min exposures (60 × 2). Egg shell temperature (T(egg)) and heart rate (HR) were monitored pre- and posttreatment. Upon hatching, hatchability, body weight, and body temperature were recorded. From 14 to 35 d of age, three quarters of the chickens in each treatment were raised under ascites-inducing conditions (AIC) and the remaining birds were raised under standard brooding conditions (SBC). The T(egg) and HR decreased significantly in response to increased exposure time on d 18 of incubation. On d 19 of incubation, before the second cold exposure, the 30 × 2 group showed greater T(egg) and HR than the controls, and during the second exposure they maintained these parameters better than the 60 × 2 embryos. No treatment effect on hatchability was observed. At 35 d of age ascites incidence among 30 × 2 chickens under AIC was significantly less than that among the controls (P ascites incidence and improved growth rate under either SBC or AIC. These results may be related to a prenatal epigenetic adaptation of the thermoregulatory and cardiovascular systems to low ambient temperature. PMID:21325235

  9. DOSE-RELATED GENE EXPRESSION CHANGES IN FOREBRAIN FOLLOWING ACUTE, LOW-LEVEL CHLORPYRIFOS EXPOSURE IN NEONATAL RATS

    Ray, Anamika; Liu, Jing; Ayoubi, Patricia; Pope, Carey

    2010-01-01

    Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 hr following acute CPF exposure in seven day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following e...

  10. Dietary saturated and monounsaturated fats protect against acute acetaminophen hepatotoxicity by altering fatty acid composition of liver microsomal membrane in rats

    Shim Eugene

    2011-10-01

    Full Text Available Abstract Background Dietary polyunsaturated fats increase liver injury in response to ethanol feeding. We evaluated the effect of dietary corn oil (CO, olive oil (OO, and beef tallow (BT on fatty acid composition of liver microsomal membrane and acute acetaminophen hepatotoxicity. Methods Male Sprague-Dawley rats were fed 15% (wt/wt CO, OO or BT for 6 weeks. After treatment with acetaminophen (600 mg/kg, samples of plasma and liver were taken for analyses of the fatty acid composition and toxicity. Results Treatment with acetaminophen significantly elevated levels of plasma GOT and GPT as well as hepatic TBARS but reduced hepatic GSH levels in CO compared to OO and BT groups. Acetaminophen significantly induced protein expression of cytochrome P450 2E1 in the CO group. In comparison with the CO diet, lower levels of linoleic acid, higher levels of oleic acids and therefore much lower ratios of linoleic to oleic acid were detected in rats fed OO and BT diets. Conclusions Dietary OO and BT produces similar liver microsomal fatty acid composition and may account for less severe liver injury after acetaminophen treatment compared to animals fed diets with CO rich in linoleic acid. These findings imply that types of dietary fat may be important in the nutritional management of drug-induced hepatotoxicity.

  11. Quantitative risk assessment on the dietary exposure of Finnish children and adults to nitrite.

    Suomi, Johanna; Ranta, Jukka; Tuominen, Pirkko; Putkonen, Tiina; Bäckman, Christina; Ovaskainen, Marja-Leena; Virtanen, Suvi M; Savela, Kirsti

    2016-01-01

    Nitrite intake from the consumption of cured meat and tap water was estimated for Finnish children of 1, 3 and 6 years as well as Finnish adults of 25-74 years. Nitrite content in the foods was measured by capillary electrophoresis, and was then used together with individual food consumption data from the FINDIET 2007 and DIPP studies in a stochastic exposure assessment by a Monte Carlo Risk Assessment (MCRA) program. Nitrite intake from additive sources and tap water was assessed, and more than every 10th child between the ages 3 and 6 years was estimated to have a nitrite intake exceeding the acceptable daily intake (ADI) of nitrite. The high exposure levels were caused by frequent consumption of large portions of sausages, up to 350 g day(-1) or 750 g in 3 days, among the children. Median nitrite intake from cured meat was 0.016, 0.040, 0.033 and 0.005 mg kg(-1) body weight day(-1) for children of 1, 3 and 6 years and adults, respectively. Bayesian estimation was employed to determine safe consumption levels of sausages and cold cuts for children, and these results gave rise to new national food consumption advice. PMID:26609554

  12. Effects of dietary PCB exposure on reproduction in the white-footed mouse (Peromyscus leucopus)

    Voltura, M.B.; French, J.B.

    2007-01-01

    Studies of the impact of environmental contaminants on reproduction have typically focused on effects on fertility and subsequent reproductive failure. Contaminants may also impact reproductive output or other aspects of life history through effects on resource acquisition or allocation. We fed successfully breeding female white-footed mice (Peromyscus leucopus) diets containing polychlorinated biphenyls (2:1 Aroclor 1242:1254) at levels of 0 (n = 10), 10 (n = 12), and 25 (n = 10) ppm (mg polychlorinated biphenyls [PCBs]/kg food). After 4 months on the diets, female mice were bred with male mice maintained on control food. There was no effect of PCB exposure on litter size at birth or weaning, although fewer female mice on the 25-ppm diet gave birth. There was no effect of PCB dose on maternal metabolic rate at peak lactation or on total food (dry matter) intake during lactation. Female mice on the 10-ppm diet, however, consumed more food per pup during lactation and weaned larger pups, although these differences disappeared after 4 weeks of age. We conclude that although moderate-term exposure to PCBs did decrease the number of litters produced for high-dose female mice, it did not change litter size, pup growth rate, or energetic measures for those female mice that did successfully reproduce.

  13. Dietary exposure of Brazilian consumers to dithiocarbamate pesticides--a probabilistic approach.

    Caldas, E D; Tressou, J; Boon, P E

    2006-09-01

    A probabilistic estimation of the exposure of the Brazilian population to the dithiocarbamate pesticides was performed using the Monte Carlo Risk Assessment program (MCRA 3.5). Residue data, as CS2, for 3821 samples were obtained from the Brazilian national monitoring program on pesticide residues and from the monitoring program conducted in the Distrito Federal on rice, beans and nine fruits and vegetables. Food consumption data were obtained from a Brazilian household budget survey conducted between 2002 and 2003. Processing factors for washing, peeling or cooking were applied to the residues found in the crops. Daily intakes at the highest percentiles for the general population reached a maximum of 2.0 microg CS2/kg body weight per day (upper band of the 95% confidence interval at P99.99). Tomato, rice, apple and lettuce were the commodities which contributed most to the intake. Based on the registered uses and the toxicological profile of dithiocarbamates, the risk from exposure was evaluated assuming that all residues came from the use of ethylene-bis-dithiocarbamate (EBDC) or that a fraction of it came from the use of propineb. For this last scenario, a cumulative risk assessment was conducted. In the first scenario, the highest intake reached up to 11.9% EBDC ADI for the general population and up to 31.1% ADI for children. When 30% of the residues were considered as coming from propineb use, the values were 15.2% and 39.7% ADI, respectively. PMID:16777311

  14. Monitoring of perchlorate in diverse foods and its estimated dietary exposure for Korea populations.

    Lee, Ji-Woo; Oh, Sung-Hee; Oh, Jeong-Eun

    2012-12-01

    The perchlorate concentrations in various Korean food samples were monitored, and 663 samples belonging to 39 kinds of food were analyzed. The analysis results revealed that dairy products contain the highest average concentration of 6.34 μg/kg and high detection frequency of over 85%. Fruit and vegetables showed the next highest perchlorate concentration with an average of 6.17 μg/kg. Especially, with its average concentration of 39.9 μg/kg, spinach showed the highest perchlorate level among all target food samples studied. Tomato was followed by spinach, which showed a high perchlorate average concentration of 19.8 μg/kg, and over 7 μg/kg was detected in ham and sausage (avg. 7.31 μg/kg) and in instant noodles (avg. 7.58 μg/kg). Less than 2 μg/kg was detected in fishes, meats and beverages. The exposure dose of perchlorate in Korean by food intake was calculated on the basis of the analyzed perchlorate levels in this study. The daily perchlorate dose to which Korean adults are exposed is 0.04 μg/kg bw/day, which is lower than the RfD (0.7 μg/kg bw/day) value suggested by US NAS. This result indicates that Korean people's current exposure to perchlorate from domestic food consumption is evaluated as safe. PMID:23116718

  15. Acute pergolide exposure stiffens engineered valve interstitial cell tissues and reduces contractility in vitro.

    Capulli, Andrew K; MacQueen, Luke A; O'Connor, Blakely B; Dauth, Stephanie; Parker, Kevin Kit

    2016-01-01

    Medications based on ergoline-derived dopamine and serotonin agonists are associated with off-target toxicities that include valvular heart disease (VHD). Reports of drug-induced VHD resulted in the withdrawal of appetite suppressants containing fenfluramine and phentermine from the US market in 1997 and pergolide, a Parkinson's disease medication, in 2007. Recent evidence suggests that serotonin receptor activity affected by these medications modulates cardiac valve interstitial cell activation and subsequent valvular remodeling, which can lead to cardiac valve fibrosis and dysfunction similar to that seen in carcinoid heart disease. Failure to identify these risks prior to market and continued use of similar drugs reaffirm the need to improve preclinical evaluation of drug-induced VHD. Here, we present two complimentary assays to measure stiffness and contractile stresses generated by engineered valvular tissues in vitro. As a case study, we measured the effects of acute (24 h) pergolide exposure to engineered porcine aortic valve interstitial cell (AVIC) tissues. Pergolide exposure led to increased tissue stiffness, but it decreased both basal and active contractile tone stresses generated by AVIC tissues. Pergolide exposure also disrupted AVIC tissue organization (i.e., tissue anisotropy), suggesting that the mechanical properties and contractile functionality of these tissues are governed by their ability to maintain their structure. We expect further use of these assays to identify off-target drug effects that alter the phenotypic balance of AVICs, disrupt their ability to maintain mechanical homeostasis, and lead to VHD. PMID:27174867

  16. Effects of long-term ozone exposure and dietary vitamin E in rats

    Sato, S.; Shimura, S.; Hirose, T.; Maeda, S.; Kawakami, M.; Takishima, T.; Kimura, S.

    1980-02-01

    Rats fed on a vitamin E-deficient diet (E-depleted group) and a vitamin E-supplemented diet (E-supplemented group) were exposed to 0.3 ppm ozone for three hours daily, five days a week for seven months. Then animals from each group were sacrificed, and electron microscopic studies on the lung and biochemical examinations on the lung and liver were performed. The defensive effect of vitamin E on ozone toxicity induced by long-term exposure to ozone was not made clear by the morphological or biochemical examination of the lung. However, biochemical findings in liver of rats exposed to ozone suggested the possibility that vitamin E deficiency permits the damaging effects of lipid peroxidation on biological membranes. (JMT)

  17. Total and inorganic arsenic in dietary supplements based on herbs, other botanicals and algae—a possible contributor to inorganic arsenic exposure

    Hedegaard, Rikke Susanne Vingborg; Rokkjær, Inge; Sloth, Jens Jørgen

    2013-01-01

    The content of total and inorganic arsenic was determined in 16 dietary supplements based on herbs, other botanicals and algae purchased on the Danish market. The dietary supplements originated from various regions, including Asia, Europe and USA. The contents of total and inorganic arsenic...... was determined by inductively coupled plasma mass spectrometry (ICP-MS) and anion exchange HPLC-ICP-MS, respectively, were in the range of 0.58 to 5.0 mgkg−1 and 0.03 to 3.2 mg kg−1, respectively, with a ratio between inorganic arsenic and total arsenic ranging between 5 and 100 %. Consumption of the recommended...... dose of the individual dietary supplement would lead to an exposure to inorganic arsenic within the range of 0.07 to 13 μg day−1. Such exposure from dietary supplements would in worst case constitute 62.4 % of the range of benchmark dose lower confidence limit values (BMDL01 at 0.3 to 8 μg kg bw−1 kg−1...

  18. Effects of Pubertal Exposure to Dietary Soy on Estrogen Receptor Activity in the Breast of Cynomolgus Macaques.

    Dewi, Fitriya N; Wood, Charles E; Willson, Cynthia J; Register, Thomas C; Lees, Cynthia J; Howard, Timothy D; Huang, Zhiqing; Murphy, Susan K; Tooze, Janet A; Chou, Jeff W; Miller, Lance D; Cline, J Mark

    2016-05-01

    Endogenous estrogens influence mammary gland development during puberty and breast cancer risk during adulthood. Early-life exposure to dietary or environmental estrogens may alter estrogen-mediated processes. Soy foods contain phytoestrogenic isoflavones (IF), which have mixed estrogen agonist/antagonist properties. Here, we evaluated mammary gland responses over time in pubertal female cynomolgus macaques fed diets containing either casein/lactalbumin (n = 12) or soy protein containing a human-equivalent dose of 120 mg IF/day (n = 17) for approximately 4.5 years spanning menarche. We assessed estrogen receptor (ER) expression and activity, promoter methylation of ERs and their downstream targets, and markers of estrogen metabolism. Expression of ERα and classical ERα response genes (TFF1, PGR, and GREB1) decreased with maturity, independent of diet. A significant inverse correlation was observed between TFF1 mRNA and methylation of CpG sites within the TFF1 promoter. Soy effects included lower ERβ expression before menarche and lower mRNA for ERα and GREB1 after menarche. Expression of GATA-3, an epithelial differentiation marker that regulates ERα-mediated transcription, was elevated before menarche and decreased after menarche in soy-fed animals. Soy did not significantly alter expression of other ER activity markers, estrogen-metabolizing enzymes, or promoter methylation for ERs or ER-regulated genes. Our results demonstrate greater ER expression and activity during the pubertal transition, supporting the idea that this life stage is a critical window for phenotypic modulation by estrogenic compounds. Pubertal soy exposure decreases mammary ERα expression after menarche and exerts subtle effects on receptor activity and mammary gland differentiation. Cancer Prev Res; 9(5); 385-95. ©2016 AACR. PMID:27006379

  19. Dietary and Household Sources of Prenatal Exposure to Polybrominated Diphenyl Ethers (PBDEs) in the INMA Birth Cohort (Spain).

    Costa, Olga; Lopez-Espinosa, Maria-Jose; Vizcaino, Esther; Murcia, Mario; Iñiguez, Carmen; Navarrete-Muñoz, Eva M; Grimalt, Joan O; Tardon, Adonina; Ballester, Ferran; Fernandez-Somoano, Ana

    2016-06-01

    This study looked at predictors of exposure to polybrominated diphenyl ethers (PBDEs) with a focus on dietary and household-level factors. Concentrations of BDE-47, -99, -153, and -209 and their sum (∑PBDEs) were measured in cord serum. Spanish women (n = 541) completed two semiquantitative food frequency questionnaires during the first and third trimesters of pregnancy. The daily mean intake (grams) of eggs, dairy products, meat, cereals and pasta, vegetables and pulses, fruits, shellfish and cephalopods, and fish, and the weekly mean intake (servings) of lean, large oily, other oily, and other fish from both questionnaires were averaged. Information on house size, curtains and carpets at home, mattress type, housekeeping frequency, and television use was also collected later in gestation. Multivariate censored regression was used to assess the association between PBDE concentration (log2 transformed) and potential predictors. BDE-47, -99, -209 and ∑PBDE concentrations increased by 13.6%(95% CI:0.0, 29.0%), 21.1%(2.3, 43.5%), 21.7%(0.4, 47.5%) and 11.5%(2.2, 21.7%), respectively, per interquartile range increment in daily intake of shellfish and cephalopods. Fish intake was associated with BDE-99 (20.8%[1.7, 43.4%]). When fish was disaggregated by types, BDE-99 and ∑PBDEs increased by 13.8%(4.0, 24.7%) and 5.7%(0.8, 10.8%), respectively, per 1-serving/week increment in large oily fish intake. BDE-153 was associated with higher housekeeping frequency (35.9%[0.4, 83.9%]) and BDE-209 with foam mattress use (48.9%[5.8, 109.7%]). In conclusion, seafood consumption, higher housekeeping frequency, and foam mattress were associated with prenatal PBDE exposure. PMID:27123793

  20. Great horned owl (Bubo virginianus) dietary exposure to PCDD/DF in the Tittabawassee River floodplain in Midland, Michigan, USA.

    Coefield, Sarah J; Zwiernik, Matthew J; Fredricks, Timothy B; Seston, Rita M; Nadeau, Michael W; Tazelaar, Dustin L; Moore, Jeremy N; Kay, Denise P; Roark, Shaun A; Giesy, John P

    2010-10-01

    Soils and sediments in the floodplain of the Tittabawassee River downstream of Midland, Michigan, USA contain elevated concentrations of polychlorinated dibenzofurans (PCDF) and polychlorinated dibenzo-p-dioxins (PCDD). As a long-lived, resident top predator, the great horned owl (Bubo virginianus; GHO) has the potential to be exposed to bioaccumulative compounds such as PCDD/DF. Site-specific components of the GHO diet were collected along 115 km of the Tittabawassee, Pine, Chippewa, and Saginaw Rivers during 2005 and 2006. The site-specific GHO biomass-based diet was dominated by cottontail rabbits (Sylvilagus floridanus) and muskrats (Ondatra zibethicus). Incidental soil ingestion and cottontail rabbits were the primary contributors of PCDD/DF to the GHO diet. The great horned owl daily dietary exposure estimates were greater in the study area (SA) (3.3 to 5.0 ng 2,3,7,8-TCDD equivalents (TEQ(WHO-avian))/kg body wt/d) than the reference area (RA) (0.07 ng TEQ(WHO-Avian)/kg body wt/d). Hazard quotients (HQs) based on central tendency estimates of the average daily dose and no-observable-adverse effect level (NOAEL) for the screech owl and uncertainty factors were <1.0 for both the RA and the SA. Hazard quotients based on upper end estimates of the average daily dose and NOAEL were <1.0 in the RA and up to 3.4 in the SA. PMID:20872700

  1. Antibiotics in typical marine aquaculture farms surrounding Hailing Island, South China: Occurrence, bioaccumulation and human dietary exposure

    Highlights: • Thirty-seven antibiotics were systematically investigated in typical marine aquaculture farms. • Enrofloxacin was widely detected in the feed samples (16.6–31.8 ng/g). • ETM-H2O in the adult shrimp samples may pose a potential risk to human safety. • TMP was bioaccumulative in fish muscles. • Antibiotics were weakly bioaccumulated in mollusks. - Abstract: The occurrence, bioaccumulation, and human dietary exposure via seafood consumption of 37 antibiotics in six typical marine aquaculture farms surrounding Hailing Island, South China were investigated in this study. Sulfamethoxazole, salinomycin and trimethoprim were widely detected in the water samples (0.4–36.9 ng/L), while oxytetracycline was the predominant antibiotic in the water samples of shrimp larvae pond. Enrofloxacin was widely detected in the feed samples (16.6–31.8 ng/g) and erythromycin–H2O was the most frequently detected antibiotic in the sediment samples (0.8–4.8 ng/g). Erythromycin–H2O was the dominant antibiotic in the adult Fenneropenaeus penicillatus with concentrations ranging from 2498 to 15,090 ng/g. In addition, trimethoprim was found to be bioaccumulative in young Lutjanus russelli with a median bioaccumulation factor of 6488 L/kg. Based on daily intake estimation, the erythromycin–H2O in adult F. penicillatus presented a potential risk to human safety

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

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

    2016-10-01

    The present study aimed to assess specific cognitive processes (cognitive control and time perception) and hemodynamic correlates using functional near-infrared spectroscopy (fNIRS) during acute and prolonged high-altitude exposure. Eleven male subjects were transported via helicopter and dropped at 14 272 ft (4 350 meters) of altitude where they stayed for 4 days. Cognitive tasks, involving a conflict task and temporal bisection task, were performed at sea level the week before ascending to high altitude, the day of arrival (D0), the second (D2) and fourth (D4) day at high altitude. Cortical hemodynamic changes in the prefrontal cortex (PFC) area were monitored with fNIRS at rest and during the conflict task. Results showed that high altitude impacts information processing in terms of speed and accuracy. In the early hours of exposure (D0), participants displayed slower reaction times (RT) and decision errors were twice as high. While error rate for simple spontaneous responses remained twice that at sea level, the slow-down of RT was not detectable after 2 days at high-altitude. The larger fNIRS responses from D0 to D2 suggest that higher prefrontal activity partially counteracted cognitive performance decrements. Cognitive control, assessed through the build-up of a top-down response suppression mechanism, the early automatic response activation and the post-error adjustment were not impacted by hypoxia. However, during prolonged hypoxic exposure the temporal judgments were underestimated suggesting a slowdown of the internal clock. A decrease in cortical arousal level induced by hypoxia could consistently explain both the slowdown of the internal clock and the persistence of a higher number of errors after several days of exposure. PMID:27262217

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

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

    2016-01-01

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

  4. Oral exposure to Phytomonas serpens attenuates thrombocytopenia and leukopenia during acute infection with Trypanosoma cruzi.

    da Silva, Rosiane V; Malvezi, Aparecida D; Augusto, Leonardo da Silva; Kian, Danielle; Tatakihara, Vera Lúcia H; Yamauchi, Lucy M; Yamada-Ogatta, Sueli F; Rizzo, Luiz V; Schenkman, Sergio; Pinge-Filho, Phileno

    2013-01-01

    Mice infected with Trypanosoma cruzi, the agent of Chagas disease, rapidly develop anemia and thrombocytopenia. These effects are partially promoted by the parasite trans-sialidase (TS), which is shed in the blood and depletes sialic acid from the platelets, inducing accelerated platelet clearance and causing thrombocytopenia during the acute phase of disease. Here, we demonstrate that oral immunization of C57BL/6 mice with Phytomonas serpens, a phytoflagellate parasite that shares common antigens with T. cruzi but has no TS activity, reduces parasite burden and prevents thrombocytopenia and leukopenia. Immunization also reduces platelet loss after intraperitoneal injection of TS. In addition, passive transfer of immune sera raised in mice against P. serpens prevented platelet clearance. Thus, oral exposure to P. serpens attenuates the progression of thrombocytopenia induced by TS from T. cruzi. These findings are not only important for the understanding of the pathogenesis of T. cruzi infection but also for developing novel approaches of intervention in Chagas disease. PMID:23844182

  5. Acute crack cocaine exposure induces genetic damage in multiple organs of rats.

    Moretti, Eduardo Gregolin; Yujra, Veronica Quispe; Claudio, Samuel Rangel; Silva, Marcelo Jose Dias; Vilegas, Wagner; Pereira, Camilo Dias Seabra; de Oliveira, Flavia; Ribeiro, Daniel Araki

    2016-04-01

    Crack cocaine is a very toxic product derived from cocaine. The aim of this study was to evaluate genetic damage in multiple organs of rats following acute exposure to crack cocaine. A total of 20 Wistar rats were distributed into four groups (n = 5), as follows: 0, 4.5, 9, and 18 mg/kg body weight (b.w.) of crack cocaine administered by intraperitoneal route (i.p.). All animals were killed 24 h after intraperitoneal (i.p.) injection. The results showed that crack cocaine increased the number of micronucleated cells in bone marrow cells exposed to 18 mg/kg crack cocaine (p crack cocaine at 9 and 18 mg/kg (p crack cocaine is able to induce genomic damage in multiple organs of Wistar rats. PMID:26825523

  6. Acute low-intensity microwave exposure increases DNA single-strand breaks in rat brain cells

    Lai, H.; Singh, N.P. [Univ. of Washington, Seattle, WA (United States)

    1995-08-01

    Levels of DNA single-strand break were assayed in brain cells from rats acutely exposed to low-intensity 2,450 MHz microwaves using an alkaline microgel electrophoresis method. Immediately after 2 h of exposure to pulsed (2 {mu}s width, 500 pulses/s) microwaves, no significant effect was observed, whereas a dose rate-dependent [0.6 and 1.2 W/kg whole body specific absorption rate (SAR)] increase in DNA single-strand breaks was found in brain cells of rats at 4 h postexposure. Furthermore, in rats exposed for 2 h to continuous-wave 2,450 MHz microwaves (SAR 1.2 W/kg), increases in brain cell DNA single-strand breaks were observed immediately as well as at 4 h postexposure.

  7. Extracellular Norepinephrine, Norepinephrine Receptor and Transporter Protein and mRNA Levels Are Differentially Altered in the Developing Rat Brain Due to Dietary Iron Deficiency and Manganese Exposure

    Anderson, Joel G.; Fordahl, Steven C.; Cooney, Paula T.; Weaver, Tara L.; Colyer, Christa L.; Erikson, Keith M.

    2009-01-01

    Manganese (Mn) is an essential trace element, but overexposure is characterized by Parkinson’s like symptoms in extreme cases. Previous studies have shown Mn accumulation is exacerbated by dietary iron deficiency (ID) and disturbances in norepinephrine (NE) have been reported. Because behaviors associated with Mn neurotoxicity are complex, the goal of this study was to examine the effects of Mn exposure and ID-associated Mn accumulation on NE uptake in synaptosomes, extracellular NE concentra...

  8. Dietary Exposure of Nigerians to Mutagens and Estrogen-Like Chemicals

    Iyekhoetin Matthew Omoruyi

    2014-08-01

    Full Text Available Food and drinking water are poorly delineated sources of human exposure to chemical food mutagens and endocrine-disrupting chemicals. In this study, we investigated the presence of mutagens and chemicals exhibiting estrogenic activity in the daily diet of Nigerians, using in vitro assays. Commercially processed foods or snacks and various brands of pure water sachets were extracted by solid-phase extraction and liquid-liquid extraction, respectively. Mutagenicity was determined by the conventional Ames test and two complementary assays on two strains of Salmonella (TA 100 and TA 98, while the estrogenic activity was assessed by a yeast bioluminescent assay, using two recombinant yeast strains (Saccharomyces cerevisiae BMAEREluc/ERα and S. cerevisiae BMA64/luc. A third of the food varieties investigated (chin-chin, hamburger, suya and bean cake were mutagenic in all three assays, either in the presence or absence of S9 mix. Of the packed water samples, five out of the sixteen investigated (31%, were found to be estrogenic, with estradiol and bisphenol A equivalents ranging from 0.79 to 44.0 ng/L and 124.2 to 1,000.8 ng/L, respectively. Hence, although the current situation in Nigeria does not appear to be substantially worse than, e.g., in Europe, regular monitoring is warranted in the future.

  9. Caffeine improves performance in double poling during acute exposure to 2,000-m altitude.

    Stadheim, H K; Nossum, E M; Olsen, R; Spencer, M; Jensen, J

    2015-12-15

    There is limited research on the physiological effects of caffeine (CAF) ingestion on exercise performance during acute hypoxia. The aim of the present study was therefore to test the effect of placebo (PLA) and CAF (4.5 mg/kg) on double poling (DP) performance during acute hypoxia. Thirteen male subelite cross-country skiers (V̇o2max 72.6 ± 5.68 ml·kg(-1)·min(-1)) were included. Performance was assessed as 1) an 8-km cross-country DP time-trial (C-PT), and 2) time until task failure at a set workload equal to ∼90% of DP V̇o2max. Testing was carried out in a hypobaric chamber, at 800 mbar (Pio2: ∼125 mmHg) corresponding to ∼2,000 m above sea level in a randomized double-blinded, placebo-controlled, cross-over design. CAF improved time to task failure from 6.10 ± 1.40 to 7.22 ± 1.30 min (P exercise subjects reported lower pain in arms and rate of perceived exertion (RPE) following CAF ingestion. Throughout C-PTs similar RPE and pain was shown between treatments. However, higher heart rate was observed during the CAF 8 km (187 ± 7 vs. 185 ± 7; P < 0.05) and 90% C-PT (185 ± 7 vs. 181 ± 9) associated with increased ventilation, blood lactate, glucose, adrenaline, decreased pH, and bicarbonate. The present study demonstrates for the first time that CAF ingestion improves DP time to task failure although not consistently time trial performance during acute exposure to altitude. Mechanisms underpinning improvements seem related to reduced pain RPE and increased heart rate during CAF C-PTs. PMID:26494444

  10. Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

    Belén Feriche

    Full Text Available When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17 in conditions of normoxia (N1 and hypobaric hypoxia (HH and G2 (n = 11 in conditions of normoxia (N2 and normobaric hypoxia (NH. Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax was recorded as the highest P(mean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max (∼ 3% and maximal strength (1 RM (∼ 6% in G1 attributable to the climb to altitude (P<0.05. We also observed a stimulating effect of natural hypoxia on P(mean and P(peak in the middle-high part of the curve (≥ 60 kg; P<0.01 and a 7.8% mean increase in barbell displacement velocity (P<0.001. No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1 RM, movement velocity and power during the execution of a force-velocity curve in bench press.

  11. Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch-Góngora, Juan G; Galilea, Pedro A; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest P(mean) obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max) (∼ 3%) and maximal strength (1 RM) (∼ 6%) in G1 attributable to the climb to altitude (P<0.05). We also observed a stimulating effect of natural hypoxia on P(mean) and P(peak) in the middle-high part of the curve (≥ 60 kg; P<0.01) and a 7.8% mean increase in barbell displacement velocity (P<0.001). No changes in any of the variables examined were observed in G2. According to these data, we can state that acute exposure to natural moderate altitude as opposed to simulated normobaric hypoxia leads to gains in 1 RM, movement velocity and power during the execution of a force-velocity curve in bench press. PMID:25474104

  12. Effects of Acutely Intermittent Hypoxic Exposure on Running Economy and Physical Performance in Basketball Players.

    Kilding, Andrew E; Dobson, Bryan P; Ikeda, Erika

    2016-07-01

    Kilding, AE, Dobson, BP, and Ikeda, E. Effects of acutely intermittent hypoxic exposure on running economy and physical performance in basketball players. J Strength Cond Res 30(7): 2033-2042, 2016-The aim of this study was to determine the effect of short duration intermittent hypoxic exposure (IHE) on physical performance in basketball players. Using a single-blind placebo-controlled group design, 14 trained basketball players were subjected to 15 days of passive short duration IHE (n = 7), or normoxic control (CON, n = 7), using a biofeedback nitrogen dilution device. A range of physiological, performance, and hematological variables were measured at baseline, and 10 days after IHE. After intervention, the IHE group, relative to the CON group, exhibited improvements in the Yo-Yo intermittent recovery level 1 (+4.8 ± 1.6%; effect size [ES]: 1.0 ± 0.4) and repeated high-intensity exercise test performance (-3.5 ± 1.6%; ES: -0.4 ± 0.2). Changes in hematological parameters were minimal, although soluble transferrin receptor increased after IHE (+9.2 ± 10.1%; ES: 0.3 ± 0.3). Running economy at 11 km·h (-9.0 ± 9.7%; ES: -0.7 ± 0.7) and 13 km·h was improved (-8.2 ± 6.9%; ES: -0.7 ± 0.5), but changes to V[Combining Dot Above]O2peak, HRpeak, and lactate were unclear. In summary, acutely IHE resulted in worthwhile changes in physical performance tests among competitive basketball players. However, physiological measures explaining the performance enhancement were in most part unclear. PMID:26677826

  13. Acute exposure to lead increases myocardial contractility independent of hypertension development

    We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na+,K+-ATPase and myosin Ca2+-ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na+,K+-ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension

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

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

  15. Effects of acute exposure to magnetic field on ionic composition of frog sciatic nerve

    Objective: To evaluate the possible interaction between magnetic field and cadmium on ionic composition of frog sciatic nerve. Design: The combined effect of magnetic field and cadmium (1.5mg/kg; in lymphatic sac) were studied in frog sciatic nerves (Rana Esculenta). Sciatic nerve samples were extracted, weighed and mixed in bidistilled water in order to analyze by inductively coupled plasma (ICP) ionic composition. Setting: Frogs (Rana Esculenta) were reared in swimming-pool (Faculte des Sciences de Bizerte, Tunisia). Frogs were cared for under the Tunisian Code of Practice for the Care and Use of Animals for Scientific purpose and the Experimental Protocols were approved by the Ethics Committee. Subjects: Treated and control groups (n=6) weighing 50-100g at the time of experiments were housed in the same condition three weeks before the beginning of the experiments. Results: Acute exposure to magnetic field increased significantly the calcium (+298%, p<0.05) and iron (+50%, p<0.05) contents of frog sciatic nerve, whereas magnesium and copper contents remained unchanged. The association between magnetic field and cadmium, induced marked increase of calcium (+360%, p<0.05), whereas magnesium content remained stable. Conclusions: Magnetic field exposure alters the ionic composition in the frog sciatic nerve, especially calcium and iron. Magnetic field magnifies the effect of cadmium on calcium homeostasis. (author)

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

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

    2007-01-01

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

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

    R.S. Oliveira

    2006-12-01

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

  18. Modeling the acute health effects of astronauts from exposure to large solar particle events.

    Hu, Shaowen; Kim, Myung-Hee Y; McClellan, Gene E; Cucinotta, Francis A

    2009-04-01

    Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed. PMID:19276707

  19. Modifications of the input currents on VTA dopamine neurons following acute versus chronic cocaine exposure.

    Michaeli, Avner; Matzner, Henry; Poltyrev, Tatyana; Yaka, Rami

    2012-03-01

    Excitatory synapses on dopamine (DA) neurons in the ventral tegmental area (VTA) are modulated following exposure to various addictive drugs, including cocaine. Previously we have shown that cocaine affects GABA(A) receptor (GABA(A)R)-mediated neurotransmission in VTA DA neurons. This finding led us to reexamine the modulation of the excitatory synapse on these neurons in response to cocaine exposure, while the activity of GABA(A)R is uninterrupted. Using rat brain slices, evoked post synaptic currents (ePSC) were monitored and inhibitors of NMDA receptor (NMDAR) and AMPA receptor (AMPAR) were gradually added to inhibitors-free bath solution. Modifications in the efficacy of the excitatory synapses were evaluated by comparing AMPAR-mediated and NMDAR-mediated currents (AMPA/NMDA ratio). The lack of GABA(A)R inhibitors enabled us to examine parallel changes in the relation between GABA(A)R-mediated and NMDAR-mediated currents (GABA(A)/NMDA ratio). First, we found that AMPA/NMDA ratio measured under complete availability of GABA(A)R, is significantly higher than the ratio measured under GABA(A)R blockade. In addition, GABA(A)/NMDA ratio, but not AMPA/NMDA ratio, is augmented a few hours following in vitro acute cocaine exposure. When measured 24 h after in vivo single cocaine injection, no change in GABA(A)/NMDA ratio was observed, however, the AMPA/NMDA ratio was found to be significantly higher. Finally, a decrease in both ratios was detected in rats repeatedly injected with cocaine. Taken together, these results lead to a better understanding of the means by which cocaine modifies synaptic inputs on VTA DA neurons. The parallel changes in GABA(A)/NMDA ratio may suggest an interaction between inhibitory and excitatory neural systems. PMID:22197515

  20. [Exposure to tobacco smoke and type of acute respiratory infections in children].

    Bielska, Dorota; Trofimiuk, Emil; Ołdak, Elzbieta; Cylwik, Bogdan; Chlabicz, Sławomir

    2010-01-01

    Respiratory diseases are the most common cause of the child and family practice physicians are one of the main reasons for referral to a specialist clinic and hospital pediatric wards. The severity of respiratory disease in adolescence influenced by various factors, endo- and exogenous. Some of them, especially environmental factors can be eliminated or reduced and thus reduce the risk of developing this disease. The most common source of pollutants in dwellings is tobacco smoke. The aim of this study was to assess exposure to tobacco smoke in three years old children of attending local kindergartens in Białystok and its influence on the type of recovery from acute respiratory infections by the respondents. The study included 313 children from among the 1,200 who attend the local 51-kindergartens in Bialystok. Information on the structure of tobacco use in three-years-old-children's families and respiratory illnesses among random children were obtained, based on anonymous questionnaires completed by their carers. Exposure to tobacco smoke was based on questionnaires and serum cotinine in relation to creatinine in the urine of patients (K/K). In the 150 families surveyed children found 210 smoking people. Every day smoked 37.3% of fathers and 23.6% of mothers. Of the children surveyed--34% of the houses which where there was a prohibition on tobacco use, 35% of the houses which were smoked in enclosed areas, in 31% of homes have not been established no-smoking rules. Children who during the six-month period to attend kindergarten gone lower respiratory tract infection had mean K/K (59.57 ng/mg) higher than the ones that were healthy and underwent upper respiratory tract infection. Used by the parents of the children tested in part to reduce the exposure to tobacco smoke in the home environment was ineffective and did not influence the decrease in the incidence of lower respiratory tract. PMID:21360910

  1. Complex study of the physiological role of cadmium. IV. Effects of prolonged dietary exposure of broiler chickens to cadmium.

    Bokori, J; Fekete, S; Glávits, R; Kádár, I; Koncz, J; Kövári, L

    1996-01-01

    A 274-day long cadmium (Cd) feeding trial was carried out with broiler cockerel chickens. The diet of the control group (Cd-0, n = 6) contained no added Cd, whereas to the diet of group Cd-25 and group Cd-75 (n = 10 each) 25 ppm and 75 ppm Cd was added, respectively, in the form of CdSO4. The chickens were subjected to examinations described in detail earlier (Bokori et al., 1995b). In addition, the relative mass of five different organs (heart, liver, testis, spleen and brain), expressed as % of the body mass, was also determined. The clinical, gross and histopathological examinations and the assay of organs for mineral element content led to the following main findings. The feeding of diets containing 25 or 75 ppm Cd for more than 9 months did not cause signs indicative of acute Cd toxicosis or mortality in either group. The body mass gain of group Cd-75 chickens markedly decreased. Prolonged Cd exposure of the cockerels increased the relative mass of the liver and heart and markedly decreased that of the testes. The change in mass was proportional to the Cd load. The Cd-fed chickens developed focal pathological fatty infiltration of the liver, histiocytic infiltration of the jejunal mucosa and focal lympho-histiocytic interstitial infiltration and fibrosis of the kidney, which supports the view that prolonged Cd exposure leads to the development of subacute-chronic tissue changes in the kidney. The Cd content of the organs increased by one to three orders of magnitude, in direct proportion to the Cd load. The Cd content of most organs was 2 to 3 times as high as the value reported for broilers exposed to a similar Cd load lasting for 68 days (Bokori et al., 1995b). This indicates that the degree of Cd accumulation is markedly influenced by the duration of the Cd exposure. The highest Cd content was demonstrated in the kidney (724 mg/kg of dry matter). The Cd exposure markedly lowered the Zn, Mo and B content of the bones and the Ni content of the myocardium

  2. Long-chain perfluoroalkyl carboxylic acids in Pacific cods from coastal areas in northern Japan: A major source of human dietary exposure

    This study investigates perfluoroalkyl carboxylic acids (PFCAs) contamination of edible fish muscle from Japanese coastal waters. The concentrations of PFCAs with 8–14 carbon atoms (C8–C14) in Pacific cods in Hokkaido, Japan were 51 (median: pg/g-wet weight) for C8, 93 for C9, 99 for C10, 746 for C11, 416 for C12, 404 for C13, and 93 for C14. The levels of C9–C14 PFCAs in fish were strongly correlated to each other, but not to C8 and the other chlorinated persistent organic pollutants, indicating that C9–C14 PFCAs have a different emission source and/or bioaccumulation mechanism. The relative ratios between estimated PFCAs intake through fish consumption and the reported total dietary exposure of PFCAs were less than 1 for C8 to C9, but were more than 1 for C10 to C14. This result strongly suggests that fish consumption is a significant source of human dietary exposure to C10–C14 PFCAs. - Highlights: • Perfluoroalkyl carboxylic acids were detected in edible cod fish from Japanese coastal waters. • The levels of long-chain PFCAs in fish were independent from those of C8 and other POPs. • Long chain PFCAs intake through fish and the reported total dietary exposure were comparable. • Sea fish such as Pacific cod may be a significant human dietary source of long-chain PFCAs. - Sea fish are a significant source of long-chain perfluoroalkyl carboxylic acids for the Japanese population

  3. Acute and chronic ethanol exposure differentially regulate CB1 receptor function at glutamatergic synapses in the rat basolateral amygdala.

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

    2016-09-01

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

  4. Analysis, distribution, and dietary exposure of glyoxal and methylglyoxal in cookies and their relationship with other heat-induced contaminants.

    Arribas-Lorenzo, Gema; Morales, Francisco J

    2010-03-10

    Thermal processing of food leads to the formation of dicarbonyls such as glyoxal (GO) and methylglyoxal (MGO), which are potentially harmful because they are precursors of advanced glycation end products (AGEs). GO and MGO formation was examined during the baking process of cookies as cookies are a widely distributed food commodity in Western diets. GO and MGO were chromatographically analyzed after employment of an improved method of derivatization with orthophenylenediamine to produce stable quinoxaline derivatives. Sample extraction, cleanup, and chromatographic conditions were evaluated to provide an in-house validated procedure for GO and MGO analysis in cookies. Quantification limits were set at 1.5 and 2 mg/kg for GO and MGO, respectively, with an average recovery of 103% and a calculated precision lower than 7%. Studies were carried out both on laboratory-scale cookies under controlled conditions and on commercial samples as well. GO and MGO values in commercial cookies ranged from 4.8 to 26.0 mg/kg and from 3.7 to 81.4 mg/kg, respectively. Commercial cookies made from ammonium bicarbonate and fructose showed the highest levels of MGO. Dicarbonyls were rapidly formed on the upper side of the cookie regardless of the shape or thickness of the samples, confirming there was a surface effect. Under controlled baking conditions, the formations of GO and MGO were linearly correlated with baking time. MGO formation was related with acrylamide, a heat-processing contaminant, in commercial cookies, but this relationship was not observed for 5-hydroxymethylfurfural. Dietary exposure of the Spanish population to GO and MGO from cookies was estimated to be 213 and 216 microg/person/day, respectively. PMID:20131787

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

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

    2015-09-01

    Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system. PMID:26356390

  6. Development of short, acute exposure hazard estimates: a tool for assessing the effects of chemical spills in aquatic environments.

    Bejarano, Adriana C; Farr, James K

    2013-08-01

    Management decisions aimed at protecting aquatic resources following accidental chemical spills into rivers and coastal estuaries require estimates of toxic thresholds derived from realistic spill conditions: acute pulse exposures of short duration (h), information which often is unavailable. Most existing toxicity data (median lethal concentration or median effective concentration) come from tests performed under constant exposure concentrations and exposure durations in the 24-h to 96-h range, conditions not typical of most chemical spills. Short-exposure hazard concentration estimates were derived for selected chemicals using empirical toxicity data. Chemical-specific 5th percentile hazard concentrations (HC5) of species sensitivity distributions (SSD) from individual exposure durations (6-96 h) were derived via bootstrap resampling and were plotted against their original exposure durations to estimate HC5s and 95% confidence intervals (CIs) at shorter exposures (1, 2, and 4 h). This approach allowed the development of short-exposure HC5s for 12 chemicals. Model verification showed agreement between observed and estimated short-exposure HC5s (r(2) adjusted = 0.95, p overprotective, these were derived from environmentally realistic exposure durations, providing risk-assessors with a tool to manage field decisions. Environ Toxicol Chem 2013;32:1918-1927. © 2013 SETAC. PMID:23625642

  7. Persistence of Breakage in Specific Chromosome Bands 6 Years after Acute Exposure to Oil

    Francés, Alexandra; Hildur, Kristin; Barberà, Joan Albert; Rodríguez-Trigo, Gema; Zock, Jan-Paul; Giraldo, Jesús; Monyarch, Gemma; Rodriguez-Rodriguez, Emma; de Castro Reis, Fernanda; Souto, Ana; Gómez, Federico P.; Pozo-Rodríguez, Francisco; Templado, Cristina; Fuster, Carme

    2016-01-01

    analyses were performed in 47 exposed individuals. A total of 251 breakpoints in exposed individuals) were identified, showing a non-uniform distribution in the human ideogram. Ten chromosome bands were found to be especially prone to breakage through both statistical methods. By comparing these bands with those observed in certain exposed individuals who had already participated the previous study, it was found in both studies that four bands (2q21, 3q27, 5q31 and 17p11.2) are particularly sensitive to breakage. Additionally, the dysfunction in DNA repair mechanisms was not significantly higher in oil-exposed individuals than in non-exposed individuals. Limitations The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the high number of individuals who participated occasionally in clean-up tasks. Conclusion Our findings show the existence of at least four target bands (2q21, 3q27, 5q31 and 17p11.2) with a greater propensity to break over time after an acute exposure to oil. The breaks in these bands, which are commonly involved in hematological cancer, may explain the increase of cancer risk reported in chronically benzene-exposed individuals. In addition, a more efficiency of the DNA repair mechanisms has been detected six years after in fishermen who were highly exposed to the oil spill. To date, only this study, performed by our group on the previous and present genotoxic effects, has analyzed the chromosomal regions affected by breakage after an acute oil exposure. PMID:27479010

  8. Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

    Kennedy, Ann; Cengel, Keith

    2012-07-01

    A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

  9. Secondhand smoke, dietary fruit intake, road traffic exposures, and the prevalence of asthma: a cross-sectional study in young children.

    Lewis, S A; Antoniak, M; Venn, A J; Davies, L; Goodwin, A; Salfield, N; Britton, J; Fogarty, A W

    2005-03-01

    The authors have investigated the independent effects of exposure to secondhand smoke, road vehicle traffic, and dietary fruit intake in a cross-sectional study of asthma in young children. They surveyed all children aged 4-6 years in 235 schools in the East Midlands and East of England regions of the United Kingdom in 2003. Data on respiratory symptoms, diagnoses and treatment, smoking in the home, and dietary fruit intake were collected by parental questionnaire. A geographic information system was used to map postcodes and determine the distance of the home from the nearest main road. Responses were obtained from 11,562 children. Wheeze in the past year and physician-diagnosed asthma were reported by 14.1% and 18.2%, respectively. Both of these outcomes were more common in children who lived with a smoker, and the prevalence of asthma increased with the number of smokers in the home. Asthma prevalence was not associated with proximity of the home to a main road or with dietary fruit intake. The authors conclude that, of the potential risk factors considered in this study, preventing secondhand smoke exposure may be the most effective way of preventing asthma. PMID:15718476

  10. Genotoxic Evaluation of Mikania laevigata Extract on DNA Damage Caused by Acute Coal Dust Exposure

    Freitas, T.P.; Heuser, V.D.; Tavares, P.; Leffa, D.D.; da Silva, G.A.; Citadini-Zanette, V.; Romao, P.R.T.; Pinho, R.A.; Streck, E.L.; Andrade,V.M. [University of Extremo Catarinense, Criciuma, SC (Brazil)

    2009-06-15

    We report data on the possible antigenotoxic activity of Mikania laevigata extract (MLE) after acute intratracheal instillation of coal dust using the comet assay in peripheral blood, bone marrow, and liver cells and the micronucleus test in peripheral blood of Wistar rats. The animals were pretreated for 2 weeks with saline solution (groups 1 and 2) or MLE (100 mg/kg) (groups 3 and 4). On day 15, the animals were anesthetized with ketamine (80 mg/kg) and xylazine (20 mg/kg), and gross mineral coal dust (3 mg/0.3 mL saline) (groups 2 and 4) or saline solution (0.3 mL) (groups 1 and 3) was administered directly in the lung by intratracheal administration. Fifteen days after coal dust or saline instillation, the animals were sacrificed, and the femur, liver, and peripheral blood were removed. The results showed a general increase in the DNA damage values at 8 hours for all treatment groups, probably related to surgical procedures that had stressed the animals. Also, liver cells from rats treated with coal dust, pretreated or not with MLE, showed statistically higher comet assay values compared to the control group at 14 days after exposure. These results could be expected because the liver metabolizes a variety of organic compounds to more polar by-products. On the other hand, the micronucleus assay results did not show significant differences among groups. Therefore, our data do not support the antimutagenic activity of M. laevigata as a modulator of DNA damage after acute coal dust instillation.

  11. Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress

    Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003–2010 National Health and Nutrition Examination Survey to quantify diet's role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. - Highlights: • Cadmium may cause chronic disease through oxidative stress or inflammation. • We developed a score to quantify dietary antioxidant and anti-inflammatory intake. • Cadmium was associated with markers of oxidative stress and inflammation. • Antioxidant and anti-inflammatory intake mitigated the effects of cadmium exposure. • Dietary interventions may be effective against chronic cadmium toxicity

  12. Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress

    Colacino, Justin A.; Arthur, Anna E.; Ferguson, Kelly K.; Rozek, Laura S., E-mail: rozekl@umich.edu

    2014-05-01

    Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003–2010 National Health and Nutrition Examination Survey to quantify diet's role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. - Highlights: • Cadmium may cause chronic disease through oxidative stress or inflammation. • We developed a score to quantify dietary antioxidant and anti-inflammatory intake. • Cadmium was associated with markers of oxidative stress and inflammation. • Antioxidant and anti-inflammatory intake mitigated the effects of cadmium exposure. • Dietary interventions may be effective against chronic cadmium toxicity.

  13. Effect of prior dietary exposure to cow’s milk protein on antigen-specific and nonspecific cellular proliferation in mice

    Pedersen, Susanne Brix; Magyar, O.H.; Barkholt, Vibeke;

    2005-01-01

    -casein peptides was further assessed on cells from mice bred on a cows'-milk-free diet. Regarding the dietary effect, we found that prior oral intake of cows' milk proteins affected cell proliferation induced by culturing with cows' milk proteins in vitro, as spleen cells from mice fed a milk-containing diet...... showed a significantly greater proliferative response than did cells from mice bred on a cows'-milk-free diet. Studies of immune enhancing potentials of beta-casein peptides showed that some peptides stimulate proliferation of immune cells nonspecifically. In conclusion, these findings stress the...... cell donors. Focusing on the immunostimulatory potential of cows' milk proteins and peptides, we studied the impact of prior dietary exposure to cows' milk on proliferation of murine immune cells upon ex vivo stimulation with bovine milk proteins. Nonspecific proliferation induced by beta...

  14. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn Exposure on Sea Cucumbers (Apostichopus japonicus

    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.

  15. From pure compounds to complex exposure: Effects of dietary cadmium and lignans on estrogen, epidermal growth factor receptor, and mitogen activated protein kinase signaling in vivo.

    Ali, Imran; Hurmerinta, Teija; Nurmi, Tarja; Berglund, Marika; Rüegg, Joelle; Poutanen, Matti; Halldin, Krister; Mäkelä, Sari; Damdimopoulou, Pauliina

    2016-06-24

    Exposure to environmental endocrine active compounds correlates with altered susceptibility to disease in human populations. Chemical risk assessment is single compound based, although exposure often takes place as heterogeneous mixtures of man-made and natural substances within complex matrices like diet. Here we studied whether the effects of cadmium and enterolactone on endocrine endpoints in dietary exposure can be predicted based on pure compound effects. Ovariectomized estrogen reporter ERE-luciferase (ERE-luc) mice were maintained on diets that intrinsically contain increasing concentrations of cadmium and enterolactone precursors for three and 21 days. The activation of the ERE-luc, epidermal growth factor receptor (EGFR), mitogen activated protein kinase (MAPK)-ERK1/2, and classical estrogen responses were measured. Interactions between the diets and endogenous hormone were evaluated by challenging the animals with 17β-estradiol. Compared to animals on basal purified diet, mice consuming experimental diets were exposed to significantly higher levels of cadmium and enterolactone, yet the exposure remained comparable to typical human dietary intake. Surprisingly, we could not detect effects on endpoints regulated by pure enterolactone, such as ERE-luc activation. However, cadmium accumulation in the liver was accompanied with activation of EGFR and MAPK-ERK1/2 in line with our earlier CdCl2 studies. Further, attenuation of 17β-estradiol-induced ERE-luc response in liver by experimental diets was observed. Our findings indicate that the exposure context can have substantial effects on the activity of endocrine active compounds in vivo. Thus, whenever possible, a context that mimics human exposure should be tested along with pure compounds. PMID:27108949

  16. Acute and chronic ethanol exposure differentially affect induction of hippocampal LTP.

    Fujii, Satoshi; Yamazaki, Yoshihiko; Sugihara, Toshimichi; Wakabayashi, Ichiro

    2008-05-23

    Using hippocampal slices, we found that chronic ethanol consumption by rats induces tolerance to the impairing effects of acute ethanol treatment on induction of long-term potentiation (LTP) in CA1 neurons. In hippocampal slices from pair-fed control rats, stable LTP was induced by tetanic stimulation consisting of 25 or more pulses at 100 Hz, but not by tetanic stimulation of 15 pulses at 100 Hz, and LTP induction was blocked if the tetanus was delivered in the presence of 8.6 mM ethanol, 1 microM muscimol, a gamma-aminobutyric acid (GABA) A receptor agonist, or 2.5 microM dl-2-amino-5-phosphonovaleric acid (AP5), an N-methyl-d-aspartate (NMDA) receptor antagonist. In hippocampal slices from rats chronically fed a liquid diet containing ethanol, a tetanus consisting of 15 pulses at 100 Hz did induce stable LTP, indicating a decrease in the stimulation threshold for inducing LTP. Application of ethanol, muscimol, or AP5 did not affect LTP induction in these cells, suggesting that the effects of chronic ethanol exposure on LTP induction are mediated by a reduction in GABAergic inhibition or an increase in NMDA receptor activity in hippocampal CA1 neurons. PMID:18423576

  17. Acute, whole-body microwave exposure and testicular function of rats

    Lebovitz, R.M.; Johnson, L.

    1987-01-01

    Male Sprague-Dawley rats were exposed for 8 h to continuous-wave microwave radiation (MWR, 1.3 Ghz) at a mean specific absorbed dose rate of 9 mW/g. MWR exposure and sham-irradiation took place in unidirectionally energized cylindrical waveguide sections, within which the animals were essentially unrestrained. The MWR treatment in this setting was determined to yield an elevation of deep rectal temperature to 4.5 degrees C. The animals were taken for analysis at 6.5, 13, 26, and 52 days following treatment, which corresponded to .5, 1, 2, and 4 cycles of the seminiferous epithelium. Net mass of testes, epididymides, and seminal vesicles; daily sperm production (DSP) per testis and per gram of testis; and the number of epididymal sperm were determined. The levels of circulating follicle-stimulating hormone (FSH) and leutinizing hormone (LH) were derived via radioimmunoassay of plasma samples taken at the time of sacrifice. Despite the evident acute thermogenesis of the MWR at 9 mW/g, no substantial decrement in testicular function was found. We conclude that, in the unrestrained rat, whole body irradiation at 9 mW/g, while sufficient to induce evident hyperthermia, is not a sufficient condition for disruption of any of these key measures of testicular function.

  18. Acute, whole-body microwave exposure and testicular function of rats

    Male Sprague-Dawley rats were exposed for 8 h to continuous-wave microwave radiation (MWR, 1.3 Ghz) at a mean specific absorbed dose rate of 9 mW/g. MWR exposure and sham-irradiation took place in unidirectionally energized cylindrical waveguide sections, within which the animals were essentially unrestrained. The MWR treatment in this setting was determined to yield an elevation of deep rectal temperature to 4.5 degrees C. The animals were taken for analysis at 6.5, 13, 26, and 52 days following treatment, which corresponded to .5, 1, 2, and 4 cycles of the seminiferous epithelium. Net mass of testes, epididymides, and seminal vesicles; daily sperm production (DSP) per testis and per gram of testis; and the number of epididymal sperm were determined. The levels of circulating follicle-stimulating hormone (FSH) and leutinizing hormone (LH) were derived via radioimmunoassay of plasma samples taken at the time of sacrifice. Despite the evident acute thermogenesis of the MWR at 9 mW/g, no substantial decrement in testicular function was found. We conclude that, in the unrestrained rat, whole body irradiation at 9 mW/g, while sufficient to induce evident hyperthermia, is not a sufficient condition for disruption of any of these key measures of testicular function

  19. Sleep quality changes in insomniacs and non-insomniacs after acute altitude exposure and its relationship with acute mountain sickness

    Tang XG; Zhang JH; Gao XB; Li QN; Li JB; Yu J; Qin J; Huang L

    2014-01-01

    Xu-gang Tang,1 Ji-hang Zhang,1 Xu-bin Gao,1 Qian-ning Li,2 Jia-bei Li,1 Jie Yu1 Jun Qin,1 Lan Huang11Institute of Cardiovascular Diseases, 2Department of Neurology, Xinqiao Hospital, Third Military Medical University, Chongqing, People’s Republic of ChinaObjective: We aimed to observe the changes in subjective sleep quality among insomniacs and non-insomniacs after acute ascending to 3,700 m and its possible relationship with acute mountain sickness (A...

  20. Risk assessment of non-dietary exposure to polycyclic aromatic hydrocarbons (PAHs) via house PM2.5, TSP and dust and the implications from human hair

    Wang, Wei; Huang, Min-juan; Chan, Chuen-Yu; Cheung, Kwai Chung; Wong, Ming Hung

    2013-07-01

    To evaluate the cancer risk due to non-dietary PAHs exposure in home environment (inhalation and ingestion), exposure to fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) of PM2.5, total suspend particles (TSP) and dust in homes at two urban centers of Pearl River Delta were assessed. House PM2.5 bound PAHs in Guangzhou (GZ) ranged from 10.0 to 61.9 ng m-3 and 0.72 to 8.15 ng m-3 in Hong Kong (HK). PAH profiles found in PM2.5, TSP and dust were different than that in hair (dominated by Nap and Phe). Pyr and Flu in house dust significantly correlated with that in hair (r = 0.69; 0.55, p houses of GZ (10-5-10-4) were significantly higher than those of HK (10-6-10-5), which were also significantly higher than the cancer risks associated with house dust intake (10-7-10-5) in GZ. PAHs exposure via non-dietary route (PM2.5 and dust) was found to be 1-3 times higher than fish consumption for children and contributed to 52-76% of total PAHs intake for children and 24-50% for adults in GZ.

  1. Acute chlorine gas exposure produces transient inflammation and a progressive alteration in surfactant composition with accompanying mechanical dysfunction

    Acute Cl2 exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl2 inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60 ppm-hour Cl2 dose, and were euthanized 3, 24 and 48 h later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24 h, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24 h. Cl2 exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO3− or NO2−. Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl2 exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48 h, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl2 inhalation. - Highlights: • Effect of 60 ppm*hr Cl2 gas on lung inflammation and mechanical function examined. • Pulmonary inflammation is transient and minor. • Alterations in surfactant homeostasis and pulmonary mechanics

  2. Critical comparison of intravenous injection of TiO2 nanoparticles with waterborne and dietary exposures concludes minimal environmentally-relevant toxicity in juvenile rainbow trout Oncorhynchus mykiss

    A critical comparison of studies that have investigated tissue accumulation and toxicity of TiO2-NPs in fish is necessary to resolve inconsistencies. The present study used identical TiO2-NPs, toxicological endpoints, and fish (juvenile rainbow trout Oncorhynchus mykiss) as previous studies that investigated waterborne and dietary toxicity of TiO2-NPs, and conducted a critical comparison of results after intravenous caudal-vein injection of 50 μg of TiO2-NPs and bulk TiO2. Injected TiO2-NPs accumulated only in kidney (94% of measured Ti) and to a lesser extent in spleen; and injected bulk TiO2 was found only in kidney. No toxicity of TiO2 was observed in kidney, spleen, or other tissues. Critical comparison of these data with previous studies indicates that dietary and waterborne exposures to TiO2-NPs do not lead to Ti accumulation in internal tissues, and previous reports of minor toxicity are inconsistent or attributable to respiratory distress resulting from gill occlusion during waterborne exposure. -- Highlights: •Critical comparison of TiO2-NP toxicity studies in rainbow trout. •No evidence of TiO2-NP absorption in internal tissues. •Conclude minimal environmentally relevant toxicity of TiO2-NPs in rainbow trout. -- Critical evaluation of directly comparable investigations of TiO2-NP toxicity by waterborne, dietary, and intravenous injection exposures conclude minimal toxicity in juvenile rainbow trout

  3. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    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)

  4. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    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)

  5. Dietary salt loading and ion-poor water exposure provide insight into the molecular physiology of the rainbow trout gill epithelium tight junction complex.

    Kolosov, Dennis; Kelly, Scott P

    2016-08-01

    This study utilized dietary salt loading and ion-poor water (IPW) exposure of rainbow trout (Oncorhynchus mykiss) to further understand the role of fish gill epithelium tight junction (TJ) physiology in salt and water balance. Gill morphology, biochemistry and molecular physiology were examined, with an emphasis on genes encoding TJ proteins. Fish were either fed a control or salt-enriched diet (~10 % NaCl) for 4 weeks prior to IPW exposure for 24 h. Serum [Na(+)], [Cl(-)] and muscle moisture content were unaltered by salt feeding, but changed in response to IPW irrespective of diet. Dietary salt loading altered the morphology (reduced Na(+)-K(+)-ATPase-immunoreactive cell numbers and surface exposure of mitochondrion-rich cells), biochemistry (decreased vacuolar-type H(+)-ATPase activity) and molecular physiology (decreased nkaα1a and cftrII mRNA abundance) of the gill in a manner indicative of reduced active ion uptake activity. But in control fish and not salt-fed fish, gill mRNA abundance of nkaα1c increased and nbc decreased after IPW exposure. Genes encoding TJ proteins were typically either responsive to salt feeding or IPW, but select genes responded to combined experimental treatment (e.g. IPW responsive but only if fish were salt-fed). Therefore, using salt feeding and IPW exposure, new insights into what factors influence gill TJ proteins and the role that specific TJ proteins might play in regulating the barrier properties of the gill epithelium have been acquired. In particular, evidence suggests that TJ proteins in the gill epithelium, or the regulatory networks that control them, respond independently to external or internal stimuli. PMID:27083431

  6. Modelling the Role of Dietary Habits and Eating Behaviours on the Development of Acute Coronary Syndrome or Stroke: Aims, Design, and Validation Properties of a Case-Control Study

    Christina-Maria Kastorini

    2011-01-01

    Full Text Available In this paper the methodology and procedures of a case-control study that will be developed for assessing the role of dietary habits and eating behaviours on the development of acute coronary syndrome and stroke is presented. Based on statistical power calculations, 1000 participants will be enrolled; of them, 250 will be consecutive patients with a first acute coronary event, 250 consecutive patients with a first ischaemic stroke, and 500 population-based healthy subjects (controls, age and sex matched to the cases. Socio-demographic, clinical, dietary, psychological, and other lifestyle characteristics will be measured. Dietary habits and eating behaviours will be evaluated with a special questionnaire that has been developed for the study.

  7. Dietary exposure to perfluoroalkyl acids of specific French adult sub-populations: High seafood consumers, high freshwater fish consumers and pregnant women

    Yamada, A., E-mail: ami.s.yamada@gmail.com [Risk Assessment Directorate, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 27-31 avenue du Général Leclerc, Maisons-Alfort 94701 (France); Bemrah, N., E-mail: nawel.bemrah@anses.fr [Risk Assessment Directorate, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 27-31 avenue du Général Leclerc, Maisons-Alfort 94701 (France); Veyrand, B., E-mail: bruno.veyrand@oniris-nantes.fr [LUNAM Université, Oniris, Laboratoire d' Etude des Résidus et Contaminants dans les Aliments (LABERCA), USC INRA 1329, Nantes 44307 (France); Pollono, C., E-mail: charles.pollono@oniris-nantes.fr [LUNAM Université, Oniris, Laboratoire d' Etude des Résidus et Contaminants dans les Aliments (LABERCA), USC INRA 1329, Nantes 44307 (France); Merlo, M., E-mail: mathilde.merlo@anses.fr [Risk Assessment Directorate, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 27-31 avenue du Général Leclerc, Maisons-Alfort 94701 (France); Desvignes, V., E-mail: virginie.desvignes@anses.fr [Risk Assessment Directorate, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 27-31 avenue du Général Leclerc, Maisons-Alfort 94701 (France); Sirot, V., E-mail: sirotv@gmail.com [Risk Assessment Directorate, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 27-31 avenue du Général Leclerc, Maisons-Alfort 94701 (France); and others

    2014-09-01

    Perfluoroalkyl acids (PFAAs) are globally found in various media, including food and especially fishery products. In the present study, the dietary exposure to 15 perfluoroalkyl acids was assessed for 3 French adult populations, namely high seafood consumers, high freshwater fish consumers, and pregnant women. Purified food extracts were analysed by LC–MS/MS and PFBA, PFPA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFTrDA, PFTeDA, PFBS, PFHxS, PFHpS, PFOS and PFDS were monitored and quantified according to the isotope dilution principle. Under lower bound (LB) hypothesis (i.e. contamination values < LOD considered as 0), high freshwater fish consumers appear as the most exposed to PFOS (7.5 ng.kg{sup −1} bw.d{sup −1}), PFUnA (1.3 ng.kg{sup −1} bw.d{sup −1}), PFDA (0.4 ng.kg{sup −1} bw.d{sup −1}) and PFHpS (0.03 ng.kg{sup −1} bw.d{sup −1}) while high seafood consumers appear as the most exposed to PFOA (1.2 ng.kg{sup −1} bw.d{sup −1}), PFNA (0.2 ng.kg{sup −1} bw.d{sup −1}) and PFHxS (0.06 ng.kg{sup −1} bw.d{sup −1}). For all considered populations, the major exposure contributors are fish, seafood and water under LB hypothesis, while dairy products, bread and crispbread are the main contributors under upper bound (UB) hypothesis. Besides this food exposure assessment, further studies are needed to assess the more global PFAA exposure, taking into account indoor and outdoor air, dust and cutaneous contact, which could be other important contributors for this particular class of chemicals. - Highlights: • The dietary exposure was estimated for 15 perfluoroalkyl acids. • Despite the overestimation, the FFQ remains useful to evaluate the whole diet. • The high fish consumers are the most dietary exposed population. • Fishery products are the main exposure contributors under LB hypothesis.

  8. Dietary exposure to perfluoroalkyl acids of specific French adult sub-populations: High seafood consumers, high freshwater fish consumers and pregnant women

    Perfluoroalkyl acids (PFAAs) are globally found in various media, including food and especially fishery products. In the present study, the dietary exposure to 15 perfluoroalkyl acids was assessed for 3 French adult populations, namely high seafood consumers, high freshwater fish consumers, and pregnant women. Purified food extracts were analysed by LC–MS/MS and PFBA, PFPA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFTrDA, PFTeDA, PFBS, PFHxS, PFHpS, PFOS and PFDS were monitored and quantified according to the isotope dilution principle. Under lower bound (LB) hypothesis (i.e. contamination values < LOD considered as 0), high freshwater fish consumers appear as the most exposed to PFOS (7.5 ng.kg−1 bw.d−1), PFUnA (1.3 ng.kg−1 bw.d−1), PFDA (0.4 ng.kg−1 bw.d−1) and PFHpS (0.03 ng.kg−1 bw.d−1) while high seafood consumers appear as the most exposed to PFOA (1.2 ng.kg−1 bw.d−1), PFNA (0.2 ng.kg−1 bw.d−1) and PFHxS (0.06 ng.kg−1 bw.d−1). For all considered populations, the major exposure contributors are fish, seafood and water under LB hypothesis, while dairy products, bread and crispbread are the main contributors under upper bound (UB) hypothesis. Besides this food exposure assessment, further studies are needed to assess the more global PFAA exposure, taking into account indoor and outdoor air, dust and cutaneous contact, which could be other important contributors for this particular class of chemicals. - Highlights: • The dietary exposure was estimated for 15 perfluoroalkyl acids. • Despite the overestimation, the FFQ remains useful to evaluate the whole diet. • The high fish consumers are the most dietary exposed population. • Fishery products are the main exposure contributors under LB hypothesis

  9. The Influence of Age of Onset and Acute Anabolic Steroid Exposure on Cognitive Performance, Impulsivity, and Aggression in Men

    Hildebrandt, Tom; Langenbucher, James W.; Flores, Adrianne; Harty, Seth; Berlin, Heather A.

    2014-01-01

    A growing translational literature suggests that adolescent exposure to anabolic-androgenic steroids (AASs) leads to increased aggression and impulsivity. However, little is known about the cognitive effects of AASs among AAS users or the differences between adolescent and adult onset users. This study provides a test of the effects of acute naturalistic AAS use and age of onset (adolescent vs. adult) on measures of inhibitory control, planning and attention, and decision makin...

  10. Acute exposure to stress improves performance in trace eyeblink conditioning and spatial learning tasks in healthy men

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

    2007-01-01

    The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure, participants completed a trace eyeblink conditioning task followed by a virtual navigation Morris water task (VNMWT). Hypothalamic-pituitary-adreno...

  11. Changes of pathological and physiological indicators affecting drug metabolism in rats after acute exposure to high altitude

    Li, Wenbin; Wang, Rong; Xie, Hua; ZHANG, JUANHONG; Jia, Zhengping

    2014-01-01

    High altitude environments cause the human body to undergo a series of pathological, physiological and biochemical changes, which have a certain effect on drug pharmacokinetics. The objective of the present study was to observe changes in factors affecting pharmacokinetics in rats following acute exposure to high altitude and return to low altitude. A total of 21 male Wistar rats were randomly assigned to three groups. The rats in group A were maintained at low altitude in Shanghai, 55 m abov...

  12. Quantification of Optic Disc Edema during Exposure to High Altitude Shows No Correlation to Acute Mountain Sickness

    Willmann, Gabriel, 1977-; Fischer, M. Dominik; Schatz, Andreas; Schommer, Kai; Messias, Andre; Zrenner, Eberhart; Bartz-Schmidt, Karl U.; Gekeler, Florian

    2011-01-01

    Background The study aimed to quantify changes of the optic nerve head (ONH) during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS). This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. Methodology/Principal Findings A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3®) was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 ...

  13. Exposure Medium: Key in Identifying Free Ag+ as the Exclusive Species of Silver Nanoparticles with Acute Toxicity to Daphnia magna

    Shen, Mo-Hai; Zhou, Xiao-Xia; Yang, Xiao-Ya; Chao, Jing-Bo; Liu, Rui; Liu, Jing-Fu

    2015-04-01

    It is still not very clear what roles the various Ag species play in the toxicity of silver nanoparticles (AgNPs). In this study, we found that traditional exposure media result in uncontrollable but consistent physicochemical transformation of AgNPs, causing artifacts in determination of median lethal concentration (LC50) and hindering the identification of Ag species responsible for the acute toxicity of AgNPs to Daphnia magna. This obstacle was overcome by using 8 h exposure in 0.1 mmol L-1 NaNO3 medium, in which we measured the 8-h LC50 of seven AgNPs with different sizes and coatings, and determined the concentrations of various Ag species. The LC50 as free Ag+ of the seven AgNPs (0.37-0.44 μg L-1) agreed very well with that of AgNO3 (0.40 μg L-1), and showed the lowest value compared to that as total Ag, total Ag+, and dissolved Ag, demonstrating free Ag+ is exclusively responsible for the acute toxicity of AgNPs to D. magna, while other Ag species in AgNPs have no contribution to the acute toxicity. Our results demonstrated the great importance of developing appropriate exposure media for evaluating risk of nanomaterials.

  14. Age-related differences in pulmonary effects of acute and subchronic episodic ozone exposures in Brown Norway rats.

    Snow, Samantha J; Gordon, Christopher J; Bass, Virginia L; Schladweiler, Mette C; Ledbetter, Allen D; Jarema, Kimberly A; Phillips, Pamela M; Johnstone, Andrew F; Kodavanti, Urmila P

    2016-06-01

    Ozone (O3) is known to induce adverse pulmonary and systemic health effects. Importantly, children and older persons are considered at-risk populations for O3-induced dysfunction, yet the mechanisms accounting for the age-related pulmonary responses to O3 are uncertain. In this study, we examined age-related susceptibility to O3 using 1 mo (adolescent), 4 mo (young adult), 12 mo (adult) and 24 mo (senescent) male Brown Norway rats exposed to filtered air or O3 (0.25 and 1.00 ppm), 6 h/day, two days/week for 1 week (acute) or 13 weeks (subchronic). Ventilatory function, assessed by whole-body plethysmography, and bronchoalveolar lavage fluid (BALF) biomarkers of injury and inflammation were used to examine O3-induced pulmonary effects. Relaxation time declined in all ages following the weekly exposures; however, this effect persisted only in the 24 mo rats following a five days recovery, demonstrating an inability to induce adaptation commonly seen with repeated O3 exposures. PenH was increased in all groups with an augmented response in the 4 mo rats following the subchronic O3 exposures. O3 led to increased breathing frequency and minute volume in the 1 and 4 mo animals. Markers of pulmonary permeability were increased in all age groups. Elevations in BALF γ-glutamyl transferase activity and lung inflammation following an acute O3 exposure were noted in only the 1 and 4 mo rats, which likely received an increased effective O3 dose. These data demonstrate that adolescent and young adult animals are more susceptible to changes in ventilation and pulmonary injury/inflammation caused by acute and episodic O3 exposure. PMID:27097751

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

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

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

    Marchini, T.; Magnani, N.D. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Paz, M.L. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Vanasco, V. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Tasat, D. [CESyMA, Facultad de Ciencia Tecnología, Universidad Nacional de General San Martín, Martín de Irigoyen 3100, 1650 San Martín, Buenos Aires (Argentina); González Maglio, D.H. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); and others

    2014-01-15

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

  17. Repeated Exposure to Conditioned Fear Stress Increases Anxiety and Delays Sleep Recovery Following Exposure to an Acute Traumatic Stressor

    Greenwood, Benjamin N.; Thompson, Robert S.; Opp, Mark R.; Fleshner, Monika

    2014-01-01

    Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep–wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the develo...

  18. High Resolution ECG for Evaluation of QT Interval Variability during Exposure to Acute Hypoxia

    Zupet, P.; Finderle, Z.; Schlegel, Todd T.; Starc, V.

    2010-01-01

    Ventricular repolarization instability as quantified by the index of QT interval variability (QTVI) is one of the best predictors for risk of malignant ventricular arrhythmias and sudden cardiac death. Because it is difficult to appropriately monitor early signs of organ dysfunction at high altitude, we investigated whether high resolution advanced ECG (HR-ECG) analysis might be helpful as a non-invasive and easy-to-use tool for evaluating the risk of cardiac arrhythmias during exposure to acute hypoxia. 19 non-acclimatized healthy trained alpinists (age 37, 8 plus or minus 4,7 years) participated in the study. Five-minute high-resolution 12-lead electrocardiograms (ECGs) were recorded (Cardiosoft) in each subject at rest in the supine position breathing room air and then after breathing 12.5% oxygen for 30 min. For beat-to-beat RR and QT variability, the program of Starc was utilized to derive standard time domain measures such as root mean square of the successive interval difference (rMSSD) of RRV and QTV, the corrected QT interval (QTc) and the QTVI in lead II. Changes were evaluated with paired-samples t-test with p-values less than 0.05 considered statistically significant. As expected, the RR interval and its variability both decreased with increasing altitude, with p = 0.000 and p = 0.005, respectively. Significant increases were found in both the rMSSDQT and the QTVI in lead II, with p = 0.002 and p = 0.003, respectively. There was no change in QTc interval length (p = non significant). QT variability parameters may be useful for evaluating changes in ventricular repolarization caused by hypoxia. These changes might be driven by increases in sympathetic nervous system activity at ventricular level.

  19. Micronucleus assay in human lymphocytes as a bio dosimeter of in vivo acute and chronic exposures

    To assess the persistence over time of micronuclei (MN) in lymphocytes of cancer patients after radiotherapy and, consequently, to verify the suitability of MN test as a dosimeter for monitoring in vivo ionizing radiation damage, the cytokinesis-blocked MN assay was applied in peripheral blood lymphocytes of cervix and head and neck cancer patients (n = 34). The evaluation of data suggests that: 1) MN frequency increases linearly with the equivalent total-body absorbed dose (R2 = 0,9; P=0,015); 2) The distribution of the MN yields deviates significantly from Poisson with the increase of equivalent total-body dose (σ2/y = 1,14 mean value); 3) The comparison of spontaneous MN frequencies in healthy subjects with those in cancer patients, prior to radiotherapy, shows significant differences (p<0,01); and 4) It is observed a general decline in MN frequencies with time after radiotherapy, with considerable variations between patients. The kinetics of elimination of MN seems to follow a two-term exponential function, with a short and a long term. Patients with the highest equivalent total-body dose (total tumoral dose: 60-80 Gy) initially tend to have the fastest decline. At 6-18 months of follow-up time 11 of the 17 patients, evaluated 2-480 months post-treatment, showed higher frequencies of MN than their respective levels before radiation therapy, indicating persistence of radiation induced cytogenetic damage. Further studies modeling changes in chromosome aberrations with acute and chronic exposures should provide perspectives on biological dosimetry in accident situations in which there is a blood sampling delay and on biological monitoring of human populations exposed to ionizing radiation. (author)

  20. Acute Liver Failure Caused by ‘Fat Burners’ and Dietary Supplements: A Case Report and Literature Review

    Radha Krishna, Y; Mittal, V.; GREWAL P; Fiel, MI; SCHIANO, T.

    2011-01-01

    Globally, people are struggling with obesity. Many effective, non-conventional methods of weight reduction, such as herbal and natural dietary supplements, are increasingly being sought. Fat burners are believed to raise metabolism, burn more calories and hasten fat loss. Despite patient perceptions that herbal remedies are free of adverse effects, some supplements are associated with severe hepatotoxicity. The present report describes a young healthy woman who presented with fulminant hepati...

  1. Genotype and toxicity relationships among Hyalella azteca: I. Acute exposure to metals or low pH

    Duan, Y.; Guttman, S.I.; Oris, J.T.; Bailer, A.J.

    2000-05-01

    Comparative genotype and toxin interactions at three polymorphic enzyme loci were examined in a laboratory population of amphipods (Hyalella azteca) during acute exposure to cadmium, zinc, copper, lead, or low pH. Significant toxin-genotype interactions were observed using logistic regression to model mortality in ten of 15 analyses. Both stressor-specific and nonspecific modes of selection were observed. In general, low pH selected for different genotypes than those selected by metals, especially zinc. Different modes of selection were also observed when amphipods were exposed to different metals. These results suggest that exposure to low pH would significantly reduce the ability of H. azteca to survive subsequent contamination by metals; exposure to stressors in the reverse order would also compromise a population's chance of survival. A genetic distance analysis showed that the magnitude of genetic differentiation consistently increased among survivors compared with that of the initial populations. These increases in genetic divergence estimates suggest that acute exposure to metals or low pH may have an evolutionarily significant impact on the species. They also suggest that both genotype frequency and genetic distance measures (based on allozyme data) may be used as bioindicators for environmental monitoring programs. Validation of such bioindicators requires an understanding of the population's genetic background, genetic structure, and history.

  2. Assessment of dietary exposure to bisphenol A in the French population with a special focus on risk characterisation for pregnant French women.

    Bemrah, Nawel; Jean, Julien; Rivière, Gilles; Sanaa, Moez; Leconte, Stéphane; Bachelot, Morgane; Deceuninck, Yoann; Bizec, Bruno Le; Dauchy, Xavier; Roudot, Alain-Claude; Camel, Valérie; Grob, Konrad; Feidt, Cyril; Picard-Hagen, Nicole; Badot, Pierre-Marie; Foures, Franck; Leblanc, Jean-Charles

    2014-10-01

    Bisphenol A (BPA) is used in a wide variety of products and objects for consumers use (digital media such as CD's and DVD's, sport equipment, food and beverage containers, medical equipment). Here, we demonstrate the ubiquitous presence of this contaminant in foods with a background level of contamination of less than 5 μg/kg in 85% of the 1498 analysed samples. High levels of contamination (up to 400 μg/kg) were found in some foods of animal origin. We used a probabilistic approach to calculate dietary exposure from French individual consumption data for infants under 36 months, children and adolescents from 3 to 17 years, adults over 18 years and pregnant women. The estimated average dietary exposure ranged from 0.12 to 0.14 μg/kg body weight per day (bw/d) for infants, from 0.05 to 0.06 μg/kg bw/d for children and adolescents, from 0.038 to 0.040 μg/kg bw/d for adults and from 0.05 to 0.06 μg/kg bw/d for pregnant women. The main sources of exposure were canned foods (50% of the total exposure), products of animal origin (20%) and 30% as a background level. Based on the toxicological values set by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) for pregnant women, the risk was non negligible. Thus, we simulated scenarios to study the influence of cans and/or food of animal origin on the BPA-related risk for this specific population. PMID:25014159

  3. Assessment of dietary exposure to flavouring substances via consumption of flavoured teas. Part II: transfer rates of linalool and linalyl esters into Earl Grey tea infusions.

    Orth, Anne-Marie; Poplacean, Iulia; Fastowski, Oxana; Engel, Karl-Heinz

    2014-01-01

    The assessment of dietary exposure via the consumption of flavoured foods is a key element of the safety evaluation of flavouring substances. Linalyl acetate and linalool are the major flavouring substances in Earl Grey teas; the objective of this study was to determine their transfer rates from the tea leaves into the tea beverage upon preparation of a hot water infusion. Spiking experiments revealed a transfer rate of 66% for linalool. In contrast, the transfer rate for linalyl acetate was only 1.9%; in turn, the hydrolysis product linalool (17.0%) and a spectrum (19.9%) of degradation and rearrangement products (monoterpene alcohols, esters and hydrocarbons) were present in the tea beverage. The transfer rates were shown to be proportional to the length of the infusion. The impact of the hot water treatment on the enantiomeric compositions of linalyl acetate and linalool was determined, and structure-dependent experiments were performed by variation of the acyl and the alcohol moiety of the monoterpene ester. Comparative dietary exposure assessments demonstrated the need to take correction factors based on the experimentally determined transfer rates into account. Based on tea consumption data from the UK National Diet and Nutrition Survey (2000/2001), the exposure to linalyl acetate ranges from 0.2 mg day(-1) (average) to 1.8 mg day(-1) (high). The corresponding values for linalool are 4.2 mg day(-1) (average) and 46.6 mg day(-1) (high). The exposure of linalool via consumption of the tea beverage is approximately 26 times higher than that of linalyl acetate, although in the flavoured tea leaves the median content of linalyl acetate is approximately 1.8 times higher than that of linalool. PMID:24237351

  4. PSA-Based Screening Outcomes, Dietary Heterocyclic Amine Exposure, and Prostate Cancer Risk in African Americans: Annual Report (Year 1 of 3)

    Bogen, K T

    2006-01-18

    Prostate cancer (PC) is the second leading cause of male U.S. cancer deaths, with African-Americans having the highest rate of PC mortality worldwide, as well as more abnormal results from screening tests that correlate with current or eventual PC. A 3-year prospective clinic-based study is studying the performance of current (PSA and DRE) vs. (% free PSA) clinical biomarkers of PC risk in 400 African-American men 50 to 70 years of age who undergo PC screening in Oakland, CA (East Bay San Francisco area), as well as possible association of PC screening results for these men with their dietary exposures to the cancer-causing heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) that forms when meat is cooked. This study expands an ongoing NIH-funded study (by the same research team) to add a new %-free-PSA test, results of which will be compared with PSA/DRE results and PhIP exposures estimated by dietary interviews. For 392 men studied under the NIH protocol, an odds ratio (95% CL) of 32 (3.2, 720) for highly elevated PSA ({ge}20 ng/mL) was observed in the highest 15% vs. the lower 50% of estimated daily PhIP intakes. Approximately 100 additional men have completed participation in the expanded NIH/DOD-supported study. This study will help define the potential value of improved screening and dietary/behavioral intervention to reduce PC risk, namely, prevention of PhIP intake by avoiding overcooked meats.

  5. Sensitivity of a green alga to atrazine is not enhanced by previous acute exposure

    Exposure to atrazine in small lotic systems can be episodic, with short-term pulses (peaks) followed by lower, decreasing concentrations. Algae and macrophytes recover rapidly from pulsed exposure to atrazine, but reported observations of population response to subsequent exposures are minimal and inconclusive. Consequently, the sensitivity of Pseudokirchneriella subcapitata to atrazine following a pulsed exposure was assessed. Exposure concentrations reflected amplifications of those observed in streams from highly vulnerable watersheds in regions of intense use. Initial pulsed atrazine exposure at 0, 150 or 300 μg/L for 24-h was followed by 72-h exposure to 0, 5, 10, 25, or 50 μg/L. Measured responses were cell density, growth rate, chlorophyll-a, and maximum quantum yield of photosystem II. Algal recovery was rapid and prior pulsed exposure to atrazine did not significantly affect subsequent sensitivity (EC10s, EC25s) for any endpoint, indicating no changes in tolerance at the population level for this species. -- Highlights: •Exposures in aquatic ecosystems to many herbicides are episodic. •Pulsed exposure to atrazine does not increase sensitivity of Pseudokirchneriella subcapitata in subsequent exposures. •Recovery of algal growth from a pulsed exposure to atrazine occurs within 24 h. -- A pulsed exposure to atrazine does not influence subsequent response to a second, reduced range of exposures in an alga. Recovery in all endpoints is rapid

  6. Large-scale analysis of acute ethanol exposure in zebrafish development: a critical time window and resilience.

    Shaukat Ali

    Full Text Available BACKGROUND: In humans, ethanol exposure during pregnancy causes a spectrum of developmental defects (fetal alcohol syndrome or FAS. Individuals vary in phenotypic expression. Zebrafish embryos develop FAS-like features after ethanol exposure. In this study, we ask whether stage-specific effects of ethanol can be identified in the zebrafish, and if so, whether they allow the pinpointing of sensitive developmental mechanisms. We have therefore conducted the first large-scale (>1500 embryos analysis of acute, stage-specific drug effects on zebrafish development, with a large panel of readouts. METHODOLOGY/PRINCIPAL FINDINGS: Zebrafish embryos were raised in 96-well plates. Range-finding indicated that 10% ethanol for 1 h was suitable for an acute exposure regime. High-resolution magic-angle spinning proton magnetic resonance spectroscopy showed that this produced a transient pulse of 0.86% concentration of ethanol in the embryo within the chorion. Survivors at 5 days postfertilisation were analysed. Phenotypes ranged from normal (resilient to severely malformed. Ethanol exposure at early stages caused high mortality (≥88%. At later stages of exposure, mortality declined and malformations developed. Pharyngeal arch hypoplasia and behavioral impairment were most common after prim-6 and prim-16 exposure. By contrast, microphthalmia and growth retardation were stage-independent. CONCLUSIONS: Our findings show that some ethanol effects are strongly stage-dependent. The phenotypes mimic key aspects of FAS including craniofacial abnormality, microphthalmia, growth retardation and behavioral impairment. We also identify a critical time window (prim-6 and prim-16 for ethanol sensitivity. Finally, our identification of a wide phenotypic spectrum is reminiscent of human FAS, and may provide a useful model for studying disease resilience.

  7. Comparative response of dogs and monkeys to sublethal acute and continuous low dose-rate gamma-ray exposure

    Monkeys (Macaca mulatta) and dogs (beagle) were given thirteen 100-rad gamma-ray doses at 28-day intervals. The comparative response (injury and recovery) of the hematopoietic system of the two species was observed at 7-day intervals during the exposure regime. At 84 days after the thirteenth gamma-ray dose, the 1300-rad conditioned and control dogs and monkeys were challenged continuously with 35 R/day until death to determine the amount of radiation-induced injury remaining in conditioned animals as a reduction in mean survival time. Dogs (50 percent) and monkeys (8 percent) died from injury incurred during the conditioning exposures. Thus, the comparative response of dogs and monkeys to dose protraction by acute dose fractionation was similar to what might be expected from a single acute dose. Mean survival times for nonconditioned dogs and monkeys during continuous exposure at 35 R/day were the same (approximately 1400 h). Thus, hematopoietic response of the two species by this method of dose protraction was not significantly different. Mean survival times of conditioned dogs and monkeys during the continuous 35 R/day gamma-ray challenge exposure were greater than for their control counterparts. Thus, the long-term radiation-induced injury was not measurable by this method. Conditioning doses of more than four times the acute LD50-30 in dogs and approximately two times that of monkeys served only to increase both mean survival time and variance in a gamma-ray stress environment with a dose rate of 35 R/day

  8. Dietary biomarkers: advances, limitations and future directions

    Hedrick Valisa E; Dietrich Andrea M; Estabrooks Paul A; Savla Jyoti; Serrano Elena; Davy Brenda M

    2012-01-01

    Abstract The subjective nature of self-reported dietary intake assessment methods presents numerous challenges to obtaining accurate dietary intake and nutritional status. This limitation can be overcome by the use of dietary biomarkers, which are able to objectively assess dietary consumption (or exposure) without the bias of self-reported dietary intake errors. The need for dietary biomarkers was addressed by the Institute of Medicine, who recognized the lack of nutritional biomarkers as a ...

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

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

  10. An incident study about acute and chronic human exposure to uranium by high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS).

    Krystek, Petra; Ritsema, Rob

    2009-01-01

    From the year 2003 to 2005 around 1700 Dutch soldiers made a part of the international stabilisation force in Iraq. An incident happened as a group of four Dutch soldiers found a 30mm bullet identified as containing depleted uranium (DU). The main pathway of the acute exposure is via inhalation of small uranium containing particles, e.g. from a bullet during its explosion. To develop a method for acute exposure investigations were carried out about finding an efficient and suitable way to sample nasal mucus as medium of inhalation. Generally, in human exposure studies with regard to natural uranium (NU) or DU, urine is the matrix for analysis. Uranium concentrations in urine are based on daily ingestion depending on the composition of drinking water and food. A second possibility is the acute exposure to uranium after an incident, either through inhalation or impact. Nevertheless, the results deliver only interpretations in respect to chronic/long-term exposure. For the acute exposure procedures like sniffling out into cleansing tissues and rinsing the nose were tested with real-life samples from four soldiers involved in an incident with possibly acute exposure to uranium. For the quantification of uranium high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) was applied. PMID:18187363

  11. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    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

  12. Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

    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 β-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 different

  13. Epithelial ovarian cancer and exposure to dietary nitrate and nitrite in the NIH-AARP Diet and Health Study

    Aschebrook-Kilfoy, Briseis; Ward, Mary H.; Gierach, Gretchen L; Schatzkin, Arthur; Hollenbeck, Albert R; Sinha, Rashmi; Cross, Amanda J

    2012-01-01

    Ovarian cancer is a leading cause of cancer death among women in the United States and it has the highest mortality rate of all gynecologic cancers. Internationally, there is a five-fold variation in incidence and mortality of ovarian cancer, which suggests a role for environmental factors, including diet. Nitrate and nitrite are found in various food items and they are precursors of N-nitroso compounds, which are known carcinogens in animal models. We evaluated dietary nitrate and nitrite in...

  14. Dietary cysteine is used more efficiently by children with severe acute malnutrition with edema compared with those without edema

    Children with edematous severe acute malnutrition (SAM) produce less cysteine than do their nonedematous counterparts. They also have marked glutathione (GSH) depletion, hair loss, skin erosion, gut mucosal atrophy, and depletion of mucins. Because GSH, skin, hair, mucosal, and mucin proteins are ri...

  15. Food selection, growth and physiology in relation to dietary sodium chloride content in rainbow trout (Oncorhynchus mykiss) under chronic waterborne Cu exposure.

    Niyogi, S; Kamunde, C N; Wood, C M

    2006-05-01

    Waterborne Cu is toxic to Na(+) and Cl(-) regulation in freshwater fish, and Cu is taken up, at least in part, via the Na(+)-transport pathway in the gills. Therefore, we hypothesized that freshwater fish may mitigate the toxic effects of waterborne Cu by selecting a NaCl-enriched diet over a normal diet. We tested this hypothesis in juvenile rainbow trout (Oncorhynchus mykiss) by offering them the choice between NaCl-enriched (1.9 mmol g(-1)Na(+)) and normal (0.2 mmol g(-1)Na(+)) diets under a chronic waterborne Cu exposure of 55 microg L(-1) for a period of 28 days. Contrary to expectation, trout exhibited a preference for NaCl-enriched diet under control conditions, while exposure to chronic waterborne Cu severely disrupted their normal feeding pattern with an accompanying loss of preference for the NaCl-enriched diet. Waterborne Cu exposure also severely affected appetite and growth. Both appetite and growth gradually recovered with time, but remained significantly impaired relative to Cu-unexposed fish until the end of the exposure. Waterborne Cu exposure also significantly increased Cu accumulations in target organs (gill, liver, and gut), plasma and whole body. However, Cu accumulation decreased substantially towards the end of the exposure in target organs and whole body as well as in plasma in Cu-exposed fish with dietary choice relative to Cu-exposed fish with normal diet. These adjustments were concurrent with the gradual recovery of appetite, which also led to increased ingestion of the NaCl-enriched diet. Interestingly, this elevated dietary uptake of NaCl produced significant stimulation of Na(+) efflux in Cu-exposed fish. Subsequently, it also led to significant elevation of Na(+) levels in target organs and whole body, and restored the decrease of plasma Na(+) and Cl(-) levels in Cu-exposed fish. The NaCl supplemented diet appeared to be beneficial in compensating Na(+) and Cl(-) losses from the body induced by waterborne Cu. Overall, these results

  16. Rapidly Progressing Severe Cutaneous Adverse Reaction With Acute Kidney Injury After Drug Exposure: An Uncommon Presentation.

    Rodgers, Bradley K; Kumar, Avinash B

    2016-01-01

    Toxic epidermal necrolysis syndrome (TEN) is a rare severe cutaneous adverse drug reaction that involves skin and mucous membranes. We describe a case of TEN presenting with stage III acute kidney injury, rhabdomyolysis, and acute respiratory failure likely triggered by allopurinol for recently diagnosed gout. Prompt diagnosis, multidisciplinary management, including aggressive resuscitation, cardiorespiratory support, intravenous immunoglobulin therapy, and daily wound care resulted in a positive outcome despite a predicted mortality greater than 60%. Although allopurinol is a known triggering agent, TEN presenting with rhabdomyolysis and acute kidney injury is rare. PMID:24832386

  17. Risk Analysis of Acute Or Chronic Exposure to Arsenic of the Inhabitants in a District of Buenos Aires, Argentina

    Cristina Vázquez

    2016-09-01

    Full Text Available The arsenic occurrence in the water constitutes a serious world health concern due to its toxicity. Depending on the intensity and duration of exposure, this element can be acutely lethal or may have a wide range of health effects in humans and animals. In Argentina, the origin of arsenic is mainly natural, and related to different geological processes. The Argentinean concern about arsenic and its influence on human health dates back to the previous century. The disease ascribed to arsenic contamination was called ‘chronic regional endemic hydroarsenism’. It is produced by the consumption of water with high levels of this element. In our study, we focused in La Matanza district, a very populated site in the Buenos Aires Province. An increasing concern of the inhabitants of the area regarding health problems was detected. In order to establish a full view of arsenic exposure in the area, several matrices and targets were analyzed. As matrices, water and soil samples were analyzed. As targets, canine and human hair was studied. The aim of this study was to investigate acute and chronically exposure to arsenic of La Matanza inhabitants.

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

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

    2016-01-01

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

  19. Effect of repetitive acute cold exposures during the last phase of broiler embryogenesis on cold resistance through the life span.

    Shinder, D; Rusal, M; Giloh, M; Yahav, S

    2009-03-01

    The time just before hatch is critical, because the embryo shifts toward internal and external pipping. This study aimed to determine the beneficial effect of repeated acute reductions of the incubation temperature during the last phase of broiler embryogenesis on posthatch cold tolerance and on the development of ascites syndrome. Fertile eggs were incubated at 37.8 degrees C and 56% RH. At 18 and 19 d of incubation, 3 treatments were conducted, comprising 2 or 3 exposures to 15 degrees C for 30 or 60 min each. During these cold exposures, egg temperature was measured by infrared thermography to determine sensible heat loss from the eggs. At hatch, BW and body temperature were measured. At 3 and 14 d of age, chicks were challenged by cold exposure to 10 degrees C for 3 h. From 14 d of age onward, three-quarters of the chicks were raised under ascites-inducing conditions (AIC) and the others were raised under regular conditions. The sensible heat loss from the eggs was 512 +/- 66 cal and 718 +/- 126 cal for 30 and 60 min of cold exposure, respectively. No effect of treatment on hatchability was observed, but body temperature and BW were greater to significantly greater in the treated chicks. Cold challenges at 3 and 14 d of age revealed a relative thermoregulatory advantage of embryos exposed to cold for 60 min. Under AIC, fewer treated chickens than controls developed ascites. At 38 d of age, BW and relative breast muscle weight were numerically to significantly greater in the treated chicks than in the control chicks when both were raised under regular conditions, whereas no differences were observed among the chicks raised under AIC. Repeated brief acute cold exposures during the last phase of embryogenesis appeared to improve the ability of growing broilers to withstand low ambient temperatures during their life span. Moreover, chickens treated during embryogenesis improved their performance under regular growth conditions. PMID:19211536

  20. The effects of acute waterborne exposure to sublethal concentrations of molybdenum on the stress response in rainbow trout, Oncorhynchus mykiss.

    Chelsea D Ricketts

    Full Text Available To determine if molybdenum (Mo is a chemical stressor, fingerling and juvenile rainbow trout (Oncorhynchus mykiss were exposed to waterborne sodium molybdate (0, 2, 20, or 1,000 mg l-1 of Mo and components of the physiological (plasma cortisol, blood glucose, and hematocrit and cellular (heat shock protein [hsp] 72, hsp73, and hsp90 in the liver, gills, heart, and erythrocytes and metallothionein [MT] in the liver and gills stress responses were measured prior to initiation of exposure and at 8, 24, and 96 h. During the acute exposure, plasma cortisol, blood glucose, and hematocrit levels remained unchanged in all treatments. Heat shock protein 72 was not induced as a result of exposure and there were no detectable changes in total hsp70 (72 and 73, hsp90, and MT levels in any of the tissues relative to controls. Both fingerling and juvenile fish responded with similar lack of apparent sensitivity to Mo exposure. These experiments demonstrate that exposure to waterborne Mo of up to 1,000 mg l(-1 did not activate a physiological or cellular stress response in fish. Information from this study suggests that Mo water quality guidelines for the protection of aquatic life are highly protective of freshwater fish, namely rainbow trout.

  1. Acute chlorine gas exposure produces transient inflammation and a progressive alteration in surfactant composition with accompanying mechanical dysfunction

    Massa, Christopher B.; Scott, Pamela; Abramova, Elena; Gardner, Carol; Laskin, Debra L.; Gow, Andrew J., E-mail: Gow@rci.rutgers.edu

    2014-07-01

    Acute Cl{sub 2} exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl{sub 2} inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60 ppm-hour Cl{sub 2} dose, and were euthanized 3, 24 and 48 h later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24 h, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24 h. Cl{sub 2} exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO{sub 3}{sup −} or NO{sub 2}{sup −}. Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl{sub 2} exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48 h, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl{sub 2} inhalation. - Highlights: • Effect of 60 ppm*hr Cl{sub 2} gas on lung inflammation and mechanical function examined. • Pulmonary inflammation is transient and minor.

  2. Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan.

    Tasmin, Saira; Ueda, Kayo; Stickley, Andrew; Yasumoto, Shinya; Phung, Vera Ling Hui; Oishi, Mizuki; Yasukouchi, Shusuke; Uehara, Yamato; Michikawa, Takehiro; Nitta, Hiroshi

    2016-10-01

    Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7μg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10μg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in 3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being. PMID:27235903

  3. Acute stress, depression, and anxiety symptoms among English and Spanish speaking children with recent trauma exposure

    Barber, Beth A.; Kohl, Krista L.; Kassam-Adams, Nancy; Gold, Jeffrey I.

    2014-01-01

    A growing literature suggests the clinical importance of acute stress disorder (ASD) symptoms in youth following potentially traumatic events. A multisite sample of English and Spanish speaking children and adolescents (N=479) between the ages of 8 to 17, along with their caregivers completed interviews and self-report questionnaires between 2 days and one month following the event. The results indicate that children with greater total acute stress symptoms reported greater depressive (r = .4...

  4. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    Ana ePalomino

    2014-03-01

    Full Text Available Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression (CB1 receptors and enzymes that produce (DAGLα/β and NAPE-PLD and degrade (MAGL and FAAH eCB were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system (glutamate synthesizing enzymes LGA and KGA, mGluR3/5 metabotropic receptors, and NR1/2A/2B/2C-NMDA and GluR1/2/3/4-AMPA ionotropic receptor subunits and the gene expression of tyrosine hydroxylase (TH, the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-AG production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and glutamate systems. Repeated cocaine results in normalization of glutamate receptor expression, although sustained changes in eCB is observed. We suggest that cocaine-induced alterations to cerebellar eCB should be considered when analyzing the adaptations imposed by psychostimulants that

  5. The implications of re-analysing radiation-induced leukaemia in atomic bomb survivors: risks for acute and chronic exposures are different

    Implications of risk estimates, as required for practical radiation protection purposes, were explored through a preliminary re-analysis of leukaemia in the Japanese atomic bomb survivors using a biologically based cancer model. The calculations for the risks posed for contracting leukaemia pointed to important differences between low-dose-rate ('chronic') and high-dose-rate ('acute') exposures. For example, the risks caused by long-term ('chronic') exposures are calculated to be substantially lower than those for 'acute' exposures. In view of these model predictions the results of epidemiological studies are discussed. (author)

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

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

    2016-07-01

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

  7. Effects of acute millimeter wave exposure on the expression of substance P and c-fos in rat spinal cord

    Yan-wen ZHANG; Yao, Quan; Shang-cheng XU; Yu, Zheng-Ping; Guang-bin ZHANG

    2013-01-01

    Objective  To observe the expression changes in substance P (SP) and c-fos in rat spinal cord after acute millimeter-wave (MMW) exposure, and explore the mechanism of thermal hyperalgesia at the spinal level. Methods  The back skin of SD rats was exposed to 35 GHz MMW (40W/cm2) for 0s (control group), 30s, 1min, or 3min. The corresponding segment of the spinal cord was taken at 0min, 5min, 10min, 1h and 3h after MMW irradiation for total RNA and protein extraction. The expressions of SP and c...

  8. Augmented Pulmonary Responses to Acute Ozone Exposure in Obese Mice: Roles of TNFR2 and IL-13

    Williams, Alison Suzanne; Mathews, Joel Andrew; Kasahara, David Itiro; Chen, Lucas; Wurmbrand, Allison Patricia; Si, Huiqing; Shore, Stephanie Ann

    2013-01-01

    Background: Acute ozone (O3) exposure results in greater inflammation and airway hyperresponsiveness (AHR) in obese versus lean mice. Objectives: We examined the hypothesis that these augmented responses to O3 are the result of greater signaling through tumor necrosis factor receptor 2 (TNFR2) and/or interleukin (IL)-13. Methods: We exposed lean wild-type (WT) and TNFR2-deficient (TNFR2–/–) mice, and obese Cpefat and TNFR2-deficient Cpefat mice (Cpefat/TNFR2–/–), to O3 (2 ppm for 3 hr) either...

  9. Augmented Pulmonary Responses to Acute Ozone Exposure in Obese Mice: Roles of TNFR2 and IL-13

    Williams, Alison Suzanne; Mathews, Joel Andrew; Kasahara, David Itiro; Chen, Lucas; Wurmbrand, Allison Patricia; Si, Huiqing; Shore, Stephanie Ann

    2013-01-01

    Background: Acute ozone (O3) exposure results in greater inflammation and airway hyperresponsiveness (AHR) in obese versus lean mice. Objectives: We examined the hypothesis that these augmented responses to O3 are the result of greater signaling through tumor necrosis factor receptor 2 (TNFR2) and/or interleukin (IL)-13. Methods: We exposed lean wild-type (WT) and TNFR2-deficient (TNFR2–/– ) mice, and obese Cpefat and TNFR2-deficient Cpefat mice (Cpefat /TNFR2–/– ), to O3 (2 ppm for 3 hr) eit...

  10. Left Ventricular Function during Acute High-Altitude Exposure in a Large Group of Healthy Young Chinese Men

    Rao, Mingyue; Li, Jiabei; Qin, Jun; Zhang, Jihang; Gao, Xubin; Yu, Shiyong; Yu, Jie; Chen, Guozhu; Xu, Baida; Li, Huijie; Rao, Rongsheng; Huang, Lan; JIN, JUN

    2015-01-01

    Objective The purpose of this study was to observe left ventricular function during acute high-altitude exposure in a large group of healthy young males. Methods A prospective trial was conducted in Szechwan and Tibet from June to August, 2012. By Doppler echocardiography, left ventricular function was examined in 139 healthy young Chinese men at sea level; within 24 hours after arrival in Lhasa, Tibet, at 3700 m; and on day 7 following an ascent to Yangbajing at 4400 m after 7 days of acclim...

  11. Acute and sublethal effects of sequential exposure to the pesticide azinphos-methyl on juvenile earthworms (Eisenia andrei).

    Jordaan, Martine S; Reinecke, Sophié A; Reinecke, Adriaan J

    2012-04-01

    The use of organophosphate pesticides is an integral part of commercial farming activities and these substances have been implicated as a major source of environmental contamination and may impact on a range of non-target fauna. The extent to which soil dwelling non-target organisms are affected by exposure to the organophosphate azinphos-methyl was investigated through monitoring selected biomarker responses and life cycle effects under laboratory conditions in the earthworm Eisenia andrei. Standard acute toxicity tests were conducted followed by a sequential exposure regime experiment, in order to assess the effects of multiple pesticide applications on biomarker (cholinesterase activity and neutral red retention time), life-cycle (growth and reproduction) and behaviour (avoidance and burrowing activity) responses. The present study indicates that the time between exposure events was a more important variable than concentration and that a longer interval between exposures may mitigate the effects of pesticide exposure provided that the exposure concentration is low. Additionally, it was shown that E. andrei was unable to avoid the presence of azinphos-methyl in soil, even at concentrations as high as 50% of the LC(50) value, indicating that the presence of azinphos-methyl in the soil pose a realistic threat to earthworms and other soil dwelling organisms. The ChE inhibition test showed a high percentage inhibition of the enzyme in all exposure groups that survived and NRR times of exposed organisms were lower than that of the controls. The present study yielded important results that contribute to the understanding of biological impacts of pesticide pollution on the environment. Extrapolating these results can aid in optimising pesticide application regimes to mitigate the environmental effects thereof and thus ensuring sustained soil biodiversity in agricultural areas. PMID:22086221

  12. Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

    Poulsen, Sarah S.; Saber, Anne T.; Mortensen, Alicja; Szarek, Jozef; Wu, Dongmei; Williams, Andrew; Andersen, Ole; Nicklas R. Jacobsen; Yauk, Carole L.; Wallin, Hakan; Halappanavar, Sabina; Vogel, Ulla Birgitte

    2015-01-01

    Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and pla...

  13. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice

    Tallarida, Christopher S.; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-01-01

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this questio...

  14. Acute cardiovascular effects of exposure to air pollution: components, vascular mechanisms and protecting the public

    Langrish, Jeremy Patrick

    2012-01-01

    Exposure to air pollution, particularly fine and ultrafine particulate matter derived from combustion sources, has been consistently associated with increased cardiovascular morbidity and mortality. Recent controlled exposure studies demonstrate that short-term exposure to diesel exhaust, which can contribute up to 40% of urban particulate air pollution, results in impaired vascular endothelial and fibrinolytic function in healthy volunteers, and increased exercise-induced m...

  15. Evaluation of dietary exposure to minerals, trace elements and heavy metals from the muscle tissue of the lionfish Pterois volitans (Linnaeus 1758).

    Hoo Fung, Leslie A; Antoine, Johann M R; Grant, Charles N; Buddo, Dayne St A

    2013-10-01

    Twenty-five samples of Pterois volitans caught in Jamaican waters were analyzed for 25 essential, non-essential and toxic elements using Graphite Furnace Atomic Absorption Spectrophotometry (GF-AAS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Instrumental Neutron Activation Analysis (INAA). The mean values for calcium (355 mg/kg), copper (107 μg/kg), iron (0.81 mg/kg), potassium (3481 mg/kg), magnesium (322 mg/kg), manganese (0.04 mg/kg), selenium (0.47 mg/kg), sodium (700 mg/kg) and zinc (4.46 mg/kg) were used to estimate dietary intake. The percentage contribution to provisional tolerable weekly intake for a 70 kg male and a 65 kg female were also estimated for the toxic elements arsenic (1.28% M, 1.38% F), cadmium (0.26% M. 0.28% F), mercury (3.85% M, 4.15% F) and lead (0.17% M, 0.18% F). To further assess the risk of mercury toxicity and the role of mitigation provided by selenium, selenium-mercury molar ratios were calculated for all samples. All samples were shown to have a molar excess of selenium. In addition the suggested selenium health benefit value was calculated, and was positive for all samples. It was concluded that P. volitans appears to contribute modestly to mineral and trace element nutrition, while not being a significant contributor to dietary exposure of toxic elements. PMID:23891700

  16. Growth and biochemical responses of juvenile cod to acute and chronic exposure to production water from the Hibernia oil rig

    Burridge, L.; Lyons, M.; Blair, T.; Haya, K.; Lee, K. [Fisheries and Oceans Canada, Dartmouth, NS (Canada). Maritimes Region, Ocean Sciences Division

    2007-07-01

    A study was conducted in which the chemical characteristics of production water collected from the Hibernia oil production platform in June, 2006 were determined. Bioassays were also performed on juvenile cod in order to determine acute responses after 48 hour exposure to concentrations of production water ranging from 0.06 to 5 per cent. Of the 70 juvenile cod that were exposed continuously for 45 days to 0.05 per cent Hibernia production water, 8 were sacrificed and liver, gill muscle and plasma was collected for biochemical analysis at day 3, 14, 28 and 45 during the exposure. Length and weight data were also collected to compare growth rates of exposed fish with unexposed fish. Results did not reveal any difference in growth rate in cod exposed for 45 days to Hibernia production water compared to those held in untreated water under the same conditions. Tissues for mixed function oxygenase (MFO) induction are undergoing analysis.

  17. Growth and biochemical responses of juvenile cod to acute and chronic exposure to production water from the Hibernia oil rig

    A study was conducted in which the chemical characteristics of production water collected from the Hibernia oil production platform in June, 2006 were determined. Bioassays were also performed on juvenile cod in order to determine acute responses after 48 hour exposure to concentrations of production water ranging from 0.06 to 5 per cent. Of the 70 juvenile cod that were exposed continuously for 45 days to 0.05 per cent Hibernia production water, 8 were sacrificed and liver, gill muscle and plasma was collected for biochemical analysis at day 3, 14, 28 and 45 during the exposure. Length and weight data were also collected to compare growth rates of exposed fish with unexposed fish. Results did not reveal any difference in growth rate in cod exposed for 45 days to Hibernia production water compared to those held in untreated water under the same conditions. Tissues for mixed function oxygenase (MFO) induction are undergoing analysis

  18. The combined impact of plant-derived dietary ingredients and acute stress on the intestinal arachidonic acid cascade in Atlantic salmon (Salmo salar).

    Oxley, Anthony; Jolly, Cecile; Eide, Torunn; Jordal, Ann-Elise O; Svardal, Asbjørn; Olsen, Rolf-Erik

    2010-03-01

    A study was conducted to assess the effect of substituting high levels of dietary fish oil (FO) and fishmeal (FM) for vegetable oil (VO) and plant protein (PP) on the intestinal arachidonic acid (AA) cascade in the carnivorous fish species Atlantic salmon. Four diets were fed to salmon over a period of 12 months, including a control FMFO diet, with varying replacements of plant-derived ingredients: 80 % PP and 35 % VO; 40 % PP and 70 % VO; 80 % PP and 70 %VO. Subsequently, fish were examined pre- (0 h) and post- (1 h) acute stress for blood parameters and intestinal bioactive lipidic mediators of inflammation (prostaglandins). Plasma cortisol responses were greatest in the FMFO group, while 80 % PP and 70 % VO fish exhibited increased plasma chloride concentrations. The n-3:n-6 PUFA ratio in intestinal glycerophospholipids from 70 % VO groups significantly decreased in both proximal and distal regions due to elevated levels of 18 : 2n-6 and the elongation/desaturation products 20 : 2n-6 and 20 : 3n-6. Increases in n-6 PUFA were not concomitant with increased AA, although the AA:EPA ratio did vary significantly. The 40 % PP and 70 % VO diet produced the highest intestinal AA:EPA ratio proximally, which coincided with a trend in elevated levels of PGF2alpha, PGE2 and 6-keto-PGF1alpha in response to stress. PGE2 predominated over PGF2alpha and 6-keto-PGF1alpha (stable metabolite of PGI2) with comparable concentrations in both intestinal regions. Cyclo-oxygenase-2 (COX-2) mRNA expression was an order of magnitude higher in distal intestine, compared with proximal, and was significantly up-regulated following stress. Furthermore, the 80 % PP and 70 % VO diet significantly amplified proximal COX-2 induction post-stress. Results demonstrate that high replacements with plant-derived dietary ingredients can enhance COX-2 induction and synthesis of pro-inflammatory eicosanoids in the intestine of salmon in response to acute physiological stress. PMID:19943982

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

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

    2016-09-01

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

  20. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna.

    Sarapultseva, Elena I; Dubrova, Yuri E

    2016-10-01

    The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000mGy of acute γ-rays. Exposure to 1000 and 10,000mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F0 and F1Daphnia gradually declined with the dose of parental exposure and significantly decreased at dose of 100mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F0Daphnia exposed to 1000 and 10,000mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F2 total fertility was compromised only among progeny of parents that received the highest dose of 10,000mGy. We propose that the decreased fertility observed among the F2 progeny of parents exposed to 10,000mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F2 progeny of irradiated F0Daphnia exposed to the lower doses of acute γ-rays. PMID:27288911

  1. Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans via fish consumption and dioxin-like activity in fish determined by H4IIE-luc bioassay

    Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) via fish consumption in two major electronic (e) waste sites: Guiyu (GY), Guangdong Province and Taizhou (TZ), Zhejiang Province, and dioxin-like activity in fish determined by H4IIE-luc bioassay. In the present study, all fish were below EU's maximum allowable concentration in muscle of fish (4 pg WHO-TEQ/g wet wt), except crucian (4.28 pg WHO-TEQ/g wet wt) and silver carps (7.49 pg WHO-TEQ/g wet wt) collected from GY rivers. Moreover, the residual concentration in bighead carp collected from GY (2.15 pg WHO-TEQ/g wet wt) was close to the EU's action level (3 pg WHO-TEQ/g wet wt) which gives “early warning” to the competent authorities and operators to take measures to eliminate contamination. In addition, results indicated that the maximum human intake of PCDD/Fs via freshwater fish consumption in GY was 4.31 pg WHO-TEQ/kg bw/day, which exceeds the higher end of the tolerable daily intake recommended by the WHO, EC-SCF and JECFA (1–4, 2 and 2.3 pg WHO-TEQ/kg bw/day respectively). Furthermore, H4IIE-luc cell bioassay provides a very sensitive and cost-efficient screening tool for assessing the overall dioxin-like toxicity in the study, and is therefore valuable for high-throughput environmental monitoring studies. - Highlights: ► Freshwater fish are contaminated by PCDD/F at 2 e-waste sites in China. ► Guiyu residents are exposed to unsafe levels of PCDD/Fs through dietary exposure. ► H4IIE-luc cell bioassay provides a very sensitive screening tool for PCDD/Fs

  2. Acid-labile protein-adducted heterocyclic aromatic amines in human blood are not viable biomarkers of dietary exposure: A systematic study.

    Cooper, Kevin M; Brennan, Sarah F; Woodside, Jayne V; Cantwell, Marie; Guo, Xiaoxiao; Mooney, Mark; Elliott, Christopher T; Cuskelly, Geraldine J

    2016-05-01

    Heterocyclic aromatic amines (HCA) are carcinogenic mutagens formed during cooking of protein-rich foods. HCA residues adducted to blood proteins have been postulated as biomarkers of HCA exposure. However, the viability of quantifying HCAs following hydrolytic release from adducts in vivo and correlation with dietary intake are unproven. To definitively assess the potential of labile HCA-protein adducts as biomarkers, a highly sensitive UPLC-MS/MS method was validated for four major HCAs: 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) and 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx). Limits of detection were 1-5 pg/ml plasma and recoveries 91-115%. Efficacy of hydrolysis was demonstrated by HCA-protein adducts synthesised in vitro. Plasma and 7-day food diaries were collected from 122 fasting adults consuming their habitual diets. Estimated HCA intakes ranged from 0 to 2.5 mg/day. An extensive range of hydrolysis conditions was examined for release of adducted HCAs in plasma. HCA was detected in only one sample (PhIP, 9.7 pg/ml), demonstrating conclusively for the first time that acid-labile HCA adducts do not reflect dietary HCA intake and are present at such low concentrations that they are not feasible biomarkers of exposure. Identification of biomarkers remains important. The search should concentrate on stabilised HCA-peptide markers and use of untargeted proteomic and metabolomic approaches. PMID:26993956

  3. Dietary Supplementation with Olive Oil or Fish Oil and Vascular Effects of Concentrated Ambient Particulate Matter Exposure in Human Volunteers

    Background: Exposure to ambient particulate matter (PM) induces endothelial dysfunction, a risk factor for cardiovascular disease. Olive oil (OO) and fish oil (FO) supplements have beneficial effects on endothelial function. Objective: In this study we evaluated the efficacy of...

  4. Oxidative stress related to chlorpyrifos exposure in rainbow trout: Acute and medium term effects on genetic biomarkers.

    Benedetto, A; Brizio, P; Squadrone, S; Scanzio, T; Righetti, M; Gasco, L; Prearo, M; Abete, M C

    2016-05-01

    Organophosphates (OPs) are derivatives of phosphoric acid widely used in agriculture as pesticides. Chlorpyrifos (CPF) is an OP that is extremely toxic to aquatic organisms. Rainbow trout (Oncorhynchus mykiss) is considered as a sentinel model species for ecotoxicology assessment in freshwater ecosystems. An exposure study was carried out on rainbow trout to investigate genetic responses to CPF-induced oxidative stress by Real-Time PCR, and to determine the accumulation dynamics of CPF and toxic metabolite chlorpyrifos-oxon (CPF-ox) in edible parts, by HPLC-MS/MS. Among the genes considered to be related to oxidative stress, a significant increase in HSP70 mRNA levels was observed in liver samples up to 14days after CPF exposure (0.05mg/L). CPF concentrations in muscle samples reach mean values of 285.25ng/g within 96hours of exposure, while CPF-ox concentrations were always under the limit of quantification (LOQ) of the applied method. Our findings lead us to consider HSP70 as a suitable genetic marker in rainbow trout for acute and medium-term monitoring of CPF exposure, complementary to analytical determinations. PMID:27017883

  5. Contributing Factors for Acute Illness/Injury from Childhood Pesticide Exposure in North Carolina, USA, 2007–2013

    Nirmalla Barros

    2016-02-01

    Full Text Available Between 2007 and 2013, there were 685 events with evidence of a relationship between pesticide exposure and acute illness/injury among persons less than 18 years old in North Carolina (United States. Median age of children affected was 4.3 years (range: 0.2–17.9. Distribution by gender was similar across all age groups. One fatality and four high severity events were observed. The greatest proportion (42% of events had ocular exposures, followed by dermal (25% and inhalation (18% exposures. When more than one route of exposure occurred, dermal and ocular routes were the most common (46%. Almost all events took place indoors and 32 events involved contact with pets. Insecticides (53% and insect repellants (31% were the most frequent agents contributing to these events. Manual application of pesticides contributed to the greatest number of events (25%, while application through a pressurized can and use of a trigger pump were involved in 21% and 15% of events, respectively. Additional contributors were due to inappropriate storage of pesticides and improper use of the pesticide. These contributing factors can be removed or minimized if pesticides are stored outside the residence or out of the reach of children and pets, and adequate ventilation is ensured whenever pesticides are applied.

  6. Modulation of pulmonary defense mechanisms by acute exposures to nitrogen dioxide. [Staphylococcus aureus; Proteus mirabilis; Pasteurella pneumotropica

    Jakab, G.J.

    1987-02-01

    The effect of acute exposures to NO/sub 2/ on the antibacterial defenses of the murine lung was assessed following inhalation challenges with Staphylococcus aureus, Proteus mirabilis, and Pasteurella pneumotropica. With S. aureus pulmonary antibacterial defenses were suppressed at NO/sub 2/ levels of 4.0 ppm and greater. Exposure to 10.0 ppm enhanced the intrapulmonary killing of P. mirabilis which correlated with an increase in the phagocytic cell populations lavaged from the lungs; at 20.0 ppm bactericidal activity against P. mirabilis was impaired. Pulmonary antibacterial defenses against P. pneumotropica were impaired at 10.0 ppm which correlated with a decrease in the retrieved phagocytic lung cell population. Reversing the order of treatment (ie., NO/sub 2/ exposure prior to bacterial challenge) raised the threshold concentration for NO/sub 2/-induced impairment of intrapulmonary bacterial killing. With S. aureus the effect was not observed at 5.0 ppm but at 10.0 ppm and with P. mirabilis not at 20.0 ppm but at 30.0 ppm intrapulmonary killing was enhanced. Exposures up to 20.0 ppm of NO/sub 2/ did not effect the physical translocation mechanisms of the lung as quantitated by declines in pulmonary radiotracer activity following aerogenic challenge with /sup 32/P-labeled staphylococci.

  7. Enhanced biosynthesis of quercetin occurs as A photoprotective measure in Lycopersicon esculentum mill. under Acute UV-B exposure

    Abhilasha Shourie

    2014-06-01

    Full Text Available Lycopersicon esculentum respond to UV-B by enhanced synthesis of flavonoid quercetin, a strong antioxidant that helps the plants to well acclimatize to UV-B stress. Three weeks old plants of L. esculentum were subjected to acute UV-B irradiation for 20, 40 and 60 minutes daily until 28 days and analyzed for the morphological and biochemical changes. UV-B exposure for 40 and 60 minutes considerably affected the growth and biomass of L. esculentum. The leaves were deformed, developed chlorosis and abscised early as compared to the unexposed plants. Biomass declined by 35% and total chlorophyll decreased by 24.7% due to disintegration of chloroplasts. Enhancement was seen in the content of carotenoids, anthocyanins and total flavonoids by 15, 33.3 and 22.8%, respectively, which was attributed to the photoprotective role of these compounds as potential quenchers of excess excitation energy. Quercetin content decreased on UV-B exposure to 20 and 40 min, and thereafter increased significantly by 5.19% on 60 min of exposure. This pattern probably indicated that the over-expression of genes involved in its biosynthesis such as phenylalanine ammonia lyase (PAL, chalcone synthase (CHS, flavanone 3-hydroxylase (F3H and dihydroflavonol 4-reductase (DFR occurred only after certain threshold exposure (60 min, which could be the strategy for developing tolerance against UV-B stress in L. esculentum.

  8. Early growth rates and their relationships to mortalities of five breeds of chickens following exposure to acute gamma radiation stress

    Growth and mortality responses were recorded for 541 chicks, representing five different breeds of chickens, following acute exposures to gamma radiation stress at two days of age. Although there were no statistically significant differences in the LD50/30 of the five breeds studied, Cobb broilers showed the highest (1580R) and White Leghorn bantams the lowest (980R) levels, respectively. Other breeds studied included the standard White Leghorn, Athens Randombreds and a strain of feral bantam. Growth rates of body weights were proportionately more depressed by radiation stress than were body sizes, as measured by the lengths of the culmen, tarsus, middle toe and longest primary wing feather of all 32 day-old survivors. Among these structures, the length of the culmen seemed to be the least affected by radiation stress in all of the breeds studied. Feral bantams were able to tolerate the greatest depression in weight gain before exhibiting mortality at exposures below their LD50/30' while Cobb broilers tolerated the greatest depression of weight gain at higher exposure levels. There was a suggestion that those characteristics which were strongly selected for in the course of a particular breed's development were those which experienced the greatest proportional depressions following exposure to gamma radiation stress

  9. Acute effect of copper exposure on serum biochemical characteristics of common carp (Cyprinus carpio L.

    Melika Ghelichpour

    2014-07-01

    Full Text Available Effects of ambient copper was investigated on serum stress markers, sodium and enzyme levels in Common carp (Cyprinus carpio L. over a 14-d exposure period. Fish were exposed to 0, 25 and 100 μg L-1 copper (as copper sulfate and blood was sampled at 0, 3, 7 and 14 d after exposure. Serum profile was significantly affected by copper concentration, sampling time and their interaction. Increase in serum levels of cortisol, glucose, alanine aminotransferase and aspartate aminotransferase and decrease in serum sodium levels were observed in both copper-exposed groups, 3 d after copper exposure, which lasted until the end of the experiment. It is concluded that copper exposure causes stress response and sodium loss in common carp. Likewise alanine aminotransferase and aspartate aminotransferase increase after exposure which might be as results of either tissue damage or stress.

  10. Dietary exposure to volatile and non-volatile N-nitrosamines from processed meat products in Denmark.

    Herrmann, S S; Duedahl-Olesen, L; Christensen, T; Olesen, P T; Granby, K

    2015-06-01

    Recent epidemiological studies show a positive association between cancer incidence and high intake of processed meat. N-nitrosamines (NAs) in these products have been suggested as one potential causative factor. Most volatile NAs (VNAs) are classified as probable human carcinogens, whereas the carcinogenicity for the majority of the non-volatile NA (NVNA) remains to be elucidated. Danish adults (15-75 years) and children (4-6 years) consume 20 g and 16 g of processed meat per day (95th percentile), respectively. The consumption is primarily accounted for by sausages, salami, pork flank (spiced and boiled) and ham. This consumption results in an exposure to NVNA of 33 and 90 ng kg bw(-1) day(-1) for adults and children, respectively. The exposure to VNA is significantly lower amounting to 0.34 and 1.1 ng kg bw(-1) day(-1) for adults and children, respectively. Based on a BMDL10 of 29 µg kg bw(-1) day(-1) a MOE value ≥17,000 was derived for the exposure to NA known to be carcinogenic (VNA including NSAR), indicating an exposure of low concern. The exposure to the NVNA is substantially higher and if found to be of toxicological significance the exposure may be of concern. PMID:25792266

  11. The effects of acute stress exposure on neural correlates of Pavlovian conditioning with monetary gains and losses

    Andrea H Lewis

    2014-05-01

    Full Text Available Pavlovian conditioning involves the association of an inherently neutral stimulus with an appetitive or aversive outcome, such that the neutral stimulus itself acquires reinforcing properties. Across species, this type of learning has been shown to involve subcortical brain regions such as the striatum and the amygdala. It is less clear, however, how the neural circuitry involved in the acquisition of Pavlovian contingencies in humans is affected by acute stress. In the current study, we investigate the effect of acute stress exposure on Pavlovian conditioning using monetary reinforcers. Participants underwent a partial reinforcement conditioning procedure in which neutral stimuli were paired with high and low magnitude monetary gains and losses. A between-subjects design was used, such that half of the participants were exposed to cold stress while the remaining participants were exposed to a no stress control procedure. Cortisol measurements and subjective ratings were used as measures of stress. We observed an interaction between stress, valence and magnitude in the ventral striatum, with the peak in the putamen. More specifically, the stress group exhibited an increased sensitivity to magnitude in the gain domain. This effect was driven by those participants who experienced a larger increase in circulating cortisol levels in response to the stress manipulation. Taken together, these results suggest that acute stress can lead to individual differences in circulating cortisol levels which influence brain regions involved in associative learning such as the ventral striatum.

  12. Acute and chronic effects of pulse exposure of Daphnia magna to dimethoate and pirimicarb.

    Andersen, Tobias Henrik; Tjørnhøj, Rikke; Wollenberger, Leah; Slothuus, Tina; Baun, Anders

    2006-05-01

    Short-term (Daphnia magna exposed to pulses of 0.5 to 8 h in duration. During a 21-d postexposure observation period, the following parameters were monitored: Mortality, mobility, day for first offspring, animal size, weight of offspring and adults, and number of offspring produced. In general, animals exposed to a single pulse of dimethoate or pirimicarb regained mobility after 24 to 48 h in clean media. Animals exposed to repeated pulses of dimethoate did not recover mobility during a 48-h postexposure observation period, and mortality was significantly increased. Animals exposed to two pulses of pirimicarb showed less recovery of mobility compared with those exposed to one pulse. Exposure of D. magna to 30 mg/L of dimethoate or 100 microg/L of pirimicarb for 2 to 6 h resulted in a significant reduction in the number of offspring and in the average weight of offspring. The average body length was reduced after pulse exposure to 30 mg/L of dimethoate for 3 h or 70 microg/L of pirimicarb for 4 h, and these exposure concentrations caused a delay in the day for first offspring at exposure durations of 2 to 6 h. The most important new findings in the present study are that short-term (<4 h) pulse exposure of neonates to acetylcholinesterase-inhibiting pesticides caused reproductive damage in D. magna and that repeated-pulse exposure significantly increased mortality in animals that apparently had recovered after a single-pulse exposure. PMID:16704047

  13. Dietary Assessment

    The Epidemiology and Genomics Research Program's goals in Dietary Assessment are to increase the precision of dietary intake estimates by improving self-report of dietary intake and the analytic procedures for processing reported information.

  14. The combined effect of lead exposure and high or low dietary calcium on health and immunocompetence in the zebra finch (Taeniopygia guttata)

    The widespread contamination by lead and the acidification of the environment ask for a better understanding of the effects of the interaction between lead and calcium on various aspects of health, including disease defense, in wildlife. Here, we investigated the effects of chronic exposure to sublethal levels of lead, combined with high or low dietary calcium, on health and several components of immunity in male and female zebra finches (Taeniopygia guttata). Thirty individuals of each sex were randomly assigned to three groups: a control group, a group exposed to lead with an additional calcium source (i.e. grit) and a group exposed to lead without access to an extra calcium source. Lead was administered as lead acetate via the drinking water (20 ppm) for 38 consecutive days. Exposure to lead increased significantly the concentrations of lead in kidney and bone in individuals of the experimental groups. Furthermore, the lack of a calcium supplement significantly enhanced the uptake of lead. Lead did not affect health indices such as hematocrit, spleen mass and body mass, nor the adrenal stress response. Cell-mediated immune responsiveness, assessed by a delayed-type hypersensitivity response to phytohaemagglutinin, was also not affected by lead exposure. On the other hand, lead exposure did significantly suppress the secondary humoral immune response towards sheep red blood cells in females, but only when the additional calcium source was not available. This effect was not found in males, suggesting sexual differences in susceptibility of humoral immunity to lead treatment in zebra finches. - Male and female finches may respond to lead differently

  15. Dietary intake rates during infancy and childhood: a data base for estimating human exposure to environmental pollutants

    A data base of food consumption rates for infants and children up to 14 years of age has been compiled for the purpose of evaluating the potential health hazard from ingestion of food containing various forms of environmental pollutants, e.g., radionuclides, heavy metals, and others. The analysis is based on a nutritional survey conducted in the city of Dortmund, FRG. The survey comprises data for 114 infants and 176 children. Within the framework of the study the data are discussed in terms of time-averaged daily consumption rates by individuals for various food categories, i.e., milk and milk products, meat, fish, cereals, vegetables, fruit, drinks, and related subgroups. Descriptive statistics of dietary intake rates by individuals have been tabulated for several age groups. (author)

  16. Effects of a dietary intervention on acute gastrointestinal side effects and other aspects of health-related quality of life: A randomized controlled trial in prostate cancer patients undergoing radiotherapy

    Purpose: To study the effect of a dietary intervention on acute gastrointestinal side effects and other aspects of health-related quality of life (HRQOL) in prostate cancer patients referred to radiotherapy. Materials and methods: A total of 130 patients were randomly assigned to one of two groups: an intervention group (IG, n = 64), instructed to reduce their intake of insoluble dietary fibres and lactose, a standard care group (SC, n = 66), instructed to continue their normal diet. Gastrointestinal side effects and other aspects of HRQOL were evaluated from baseline up to 2 months after completed radiotherapy, using the EORTC QLQ-C30 and QLQ-PR25 and the study-specific Gastrointestinal Side Effects Questionnaire (GISEQ). A scale indicating adherence to dietary instructions was developed from a Food Frequency Questionnaire (FFQ), with lower scores representing better compliance. Descriptive and inferential statistical analyses were conducted. Results: There was an interaction effect between randomization and time in the FFQ Scores (p < 0.001), indicating that both groups followed their assigned dietary instructions. The dietary intervention had no effect on gastrointestinal side effects or other aspects of HRQOL. During radiotherapy, the percentage of patients with bowel symptoms and bloated abdomen was lower in IG compared to SC, but the between-group differences were not statistically significant. During radiotherapy, the percentage of patients with bowel symptoms, urinary symptoms, pain, fatigue and diminished physical and role functioning increased in both groups. Conclusions: The dietary intervention had no effect on gastrointestinal side effects or other aspects of HRQOL. The tendency towards lower prevalence of bowel symptoms in IG may indicate some positive effect of the dietary intervention, but methodological refinements, clearer results and longer follow-up are needed before the value of diet change can be established with certainty.

  17. Acute Phase Response, Inflammation and Metabolic Syndrome Biomarkers of Libby Asbestos Exposure

    Background: Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. Objective: We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help ...

  18. Acute Phase Response and Metabolic Syndrome Biomarkers of Libby Asbestos Exposure

    Identification of biomarkers assists in the disease diagnosis and environmental health risk assessment. Exposure to Libby amphibole (LA) has been associated with increased cardiovascular mortality. We hypothesized that rats exposed to LA would present a unique serum proteomic pro...

  19. Clinical and pathological manifestations of cardiovascular disease in rat models: the influence of acute ozone exposure

    This paper shows that rat models of cardiovascular diseases have differential degrees of underlying pathologies at a young age. Rodent models of cardiovascular diseases (CVD) and metabolic disorders are used for examining susceptibility variations to environmental exposures. How...

  20. Functional Alterations in the Dorsal Raphe Nucleus Following Acute and Chronic Ethanol Exposure

    Lowery-Gionta, Emily G; Marcinkiewcz, Catherine A.; Kash, Thomas L.

    2014-01-01

    Alcoholism is a pervasive disorder perpetuated in part to relieve negative mood states like anxiety experienced during alcohol withdrawal. Emerging evidence demonstrates a role for the serotonin-rich dorsal raphe (DR) in anxiety following ethanol withdrawal. The current study examined the effects of chronic ethanol vapor exposure on the DR using slice electrophysiology in male DBA2/J mice. We found that chronic ethanol exposure resulted in deficits in social approach indicative of increased a...

  1. Effect of chromium (VI) exposure on antioxidant defense status and trace element homeostasis in acute experiment in rat.

    Kotyzová, Dana; Hodková, Anna; Bludovská, Monika; Eybl, Vladislav

    2015-11-01

    Occupational exposure to hexavalent chromium (Cr(VI)) compounds is of concern in many Cr-related industries and their surrounding environment. Cr(VI) is a proven toxin and carcinogen. The Cr(VI) compounds are easily absorbed, can diffuse across cell membranes, and have strong oxidative potential. Despite intensive studies of Cr(VI) pro-oxidative effects, limited data exist on the influence of Cr(VI) on selenoenzymes thioredoxin reductase (TrxR) and glutathione peroxidase (GPx)-important components of antioxidant defense system. This study investigates the effect of Cr(VI) exposure on antioxidant defense status, with focus on these selenoenzymes, and on trace element homeostasis in an acute experiment in rat. Male Wistar rats (130-140g) were assigned to two groups of 8 animals: I. control; and II. Cr(VI) treated. The animals in Cr(VI) group were administered a single dose of K2Cr2O7 (20 mg /kg, intraperitoneally (ip)). The control group received saline solution. After 24 h, the animals were sacrificed and the liver and kidneys were examined for lipid peroxidation (LP; thiobarbituric acid reactive substances (TBARS) concentration), the level of reduced glutathione (GSH) and the activities of GPx-1, TrxR-1, and glutathione reductase (GR). Samples of tissues were also used to estimate Cr accumulation and alterations in zinc, copper, and iron levels. The acute Cr(VI) exposure caused an increase in both hepatic and renal LP (by 70%, p effect of Cr(VI) was found on TrxR-1 activity in both the liver and the kidneys. The ability of Cr(VI) to cause TrxR inhibition could contribute to its cytotoxic effects. Further investigation of oxidative responses in different in vivo models may enable the development of strategies to protect against Cr(VI) oxidative damage. PMID:23625905

  2. Effects of acute or chronic ethanol exposure during adolescence on behavioral inhibition and efficiency in a modified water maze task.

    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.

  3. Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches

    Fabian Herzog

    2014-08-01

    Full Text Available In the emerging market of nano-sized products, silver nanoparticles (Ag NPs are widely used due to their antimicrobial properties. Human interaction with Ag NPs can occur through the lung, skin, gastrointestinal tract, and bloodstream. However, the inhalation of Ag NP aerosols is a primary concern. To study the possible effects of inhaled Ag NPs, an in vitro triple cell co-culture model of the human alveolar/airway barrier (A549 epithelial cells, human peripheral blood monocyte derived dendritic and macrophage cells together with an air–liquid interface cell exposure (ALICE system was used in order to reflect a real-life exposure scenario. Cells were exposed at the air–liquid interface (ALI to 0.03, 0.3, and 3 µg Ag/cm2 of Ag NPs (diameter 100 nm; coated with polyvinylpyrrolidone: PVP. Ag NPs were found to be highly aggregated within ALI exposed cells with no impairment of cell morphology. Furthermore, a significant increase in release of cytotoxic (LDH, oxidative stress (SOD-1, HMOX-1 or pro-inflammatory markers (TNF-α, IL-8 was absent. As a comparison, cells were exposed to Ag NPs in submerged conditions to 10, 20, and 30 µg Ag/mL. The deposited dose per surface area was estimated by using a dosimetry model (ISDD to directly compare submerged vs ALI exposure concentrations after 4 and 24 h. Unlike ALI exposures, the two highest concentrations under submerged conditions promoted a cytotoxic and pro-inflammatory response after 24 h. Interestingly, when cell cultures were co-incubated with lipopolysaccharide (LPS, no synergistic inflammatory effects were observed. By using two different exposure scenarios it has been shown that the ALI as well as the suspension conditions for the lower concentrations after 4 h, reflecting real-life concentrations of an acute 24 h exposure, did not induce any adverse effects in a complex 3D model mimicking the human alveolar/airway barrier. However, the highest concentrations used in the ALI setup, as well

  4. The acute and sub-chronic exposures of goldfish to naphthenic acids induce different host defense responses.

    Hagen, Mariel O; Garcia-Garcia, Erick; Oladiran, Ayoola; Karpman, Matthew; Mitchell, Scott; El-Din, Mohamed Gamal; Martin, Jonathan W; Belosevic, Miodrag

    2012-03-01

    Naphthenic acids (NAs) are believed to be the major toxic component in oil sands process-affected water (OSPW) produced by the oil sands mining industry in Northern Alberta, Canada. We recently reported that oral exposure to NAs alters mammalian immune responses, but the effect of OSPW or NAs on the immune mechanisms of aquatic organisms has not been fully elucidated. We analyzed the effects of acute and sub-chronic NAs exposures on goldfish immune responses by measuring the expression of three pro-inflammatory cytokine genes, antimicrobial functions of macrophages, and host defense after challenge with a protozoan pathogen (Trypanosoma carassii). One week after NAs exposure, fish exhibited increased expression of pro-inflammatory cytokines (IFNγ, IL-1β1, TNF-α2) in the gills, kidney and spleen. Primary macrophages from fish exposed to NAs for one week, exhibited increased production of nitric oxide and reactive oxygen intermediates. Goldfish exposed for one week to 20 mg/L NAs were more resistant to infection by T. carassii. In contrast, sub-chronic exposure of goldfish (12 weeks) to NAs resulted in decreased expression of pro-inflammatory cytokines in the gills, kidney and spleen. The sub-chronic exposure to NAs reduced the ability of goldfish to control the T. carassii infection, exemplified by a drastic increase in fish mortality and increased blood parasite loads. This is the first report analyzing the effects of OSPW contaminants on the immune system of aquatic vertebrates. We believe that the bioassays depicted in this work will be valuable tools for analyzing the efficacy of OSPW remediation techniques and assessment of diverse environmental pollutants. PMID:22227375

  5. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

    Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

    2016-05-01

    A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony. PMID:26802564

  6. Histopathological and biochemical changes in rat thyroid following acute exposure to hexavalent chromium

    Mahmood, Tariq; Zia Quresh, Irfan; Javed Iqbal, Muhammad

    2010-01-01

    Chromium in hexavalent form is highly toxic and a known carcinogen, although its effects on thyroid structure and function are relatively unexplored. Workers in an industrial environment can be, at times, exposed to this form of chromium. The present study was, therefore, designed using laboratory rats as a model system to investigate the effect on thyroid structure and function following two acute intraperitoneal doses of 30 mg/kg b.w. potassium dichromate administere...

  7. Acute and chronic exposure in mussel (aulacomya ater) and clam (semelle solida) with Cs137

    Two of the most common Peruvian benthonic molluscs, have been shown to be effective concentrators of Cesium-137 and have also proven useful as indicators of that radionuclide in their natural environment, according with results in this paper. However the clam is a better indicator, when determining environmental acute release of Cesium-137 due to reactor accidents, nuclear tests, accidents in nuclear ships, submarines and radioactive material transport, and the mussel for a continuous monitoring of environmental radio contaminant levels. (author). 11 refs

  8. Acute ethanol exposure increases the susceptibility of the donor hearts to ischemia/reperfusion injury after transplantation in rats.

    Shiliang Li

    Full Text Available BACKGROUND: Many donor organs come from youths involved in alcohol-related accidental death. The use of cardiac allografts for transplantation from donors after acute poisoning is still under discussion while acute ethanol intoxication is associated with myocardial functional and morphological changes. The aims of this work were 1 to evaluate in rats the time-course cardiac effects of acute ethanol-exposure and 2 to explore how its abuse by donors might affect recipients in cardiac pump function after transplantation. METHODS: Rats received saline or ethanol (3.45 g/kg, ip. We evaluated both the mechanical and electrical aspects of cardiac function 1 h, 6 h or 24 h after injection. Plasma cardiac troponin-T and glucose-levels were measured and histological examination of the myocardium was performed. In addition, heart transplantation was performed, in which donors received ethanol 6 h or 24 h prior to explantation. Graft function was measured 1 h or 24 h after transplantation. Myocardial TBARS-concentration was measured; mRNA and protein expression was assessed by quantitative real-time PCR and Western blot, respectively. RESULTS: Ethanol administration resulted in decreased load-dependent (-34 ± 9% and load-independent (-33 ± 12% contractility parameters, LV end-diastolic pressure and elevated blood glucose levels at 1 h, which were reversed to the level of controls after 6 h and 24 h. In contrast to systolic dysfunction, active relaxation and passive stiffness are slowly recovered or sustained during 24 h. Moreover, troponin-T-levels were increased at 1 h, 6 h and 24 h after ethanol injection. ST-segment elevation (+47 ± 10%, elongated QT-interval (+38 ± 4%, enlarged cardiomyocyte, DNA-strand breaks, increased both mRNA and protein levels of superoxide dismutase-1, glutathione peroxydase-4, cytochrome-c-oxidase and metalloproteinase-9 were observed 24 h following ethanol-exposure. After heart transplantation, decreased myocardial

  9. Dose-related gene expression changes in forebrain following acute, low-level chlorpyrifos exposure in neonatal rats

    Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 h following acute CPF exposure in 7-day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following either one of the four CPF dosages studied (546, 505, 522, and 3,066 genes with 0.1, 0.5, 1.0 and 2.0 mg/kg CPF). Genes were grouped according to dose-related expression patterns using K-means clustering while gene networks and canonical pathways were evaluated using Ingenuity Pathway Analysis (registered) . Twenty clusters were identified and differential expression of selected genes was verified by RT-PCR. The four largest clusters (each containing from 276 to 905 genes) constituted over 50% of all differentially expressed genes and exhibited up-regulation following exposure to the highest dosage (2 mg/kg CPF). The total number of gene networks affected by CPF also rose sharply with the highest dosage of CPF (18, 16, 18 and 50 with 0.1, 0.5, 1 and 2 mg/kg CPF). Forebrain cholinesterase (ChE) activity was significantly reduced (26%) only in the highest dosage group. Based on magnitude of dose-related changes in differentially expressed genes, relative numbers of gene clusters and signaling networks affected, and forebrain ChE inhibition only at 2 mg/kg CPF, we focused subsequent analyses on this treatment group. Six canonical pathways were identified that were significantly affected by 2 mg/kg CPF (MAPK, oxidative stress, NFΚB, mitochondrial dysfunction, arylhydrocarbon receptor and adrenergic receptor signaling). Evaluation of different cellular functions of the differentially expressed genes suggested changes related to olfactory receptors, cell adhesion/migration, synapse

  10. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    Palomino, Ana; Pavón, Francisco-Javier; Blanco-Calvo, Eduardo; Serrano, Antonia; Arrabal, Sergio; Rivera, Patricia; Alén, Francisco; Vargas, Antonio; Bilbao, Ainhoa; Rubio, Leticia; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid receptor type 1 receptors and enzymes that produce [diacylglycerol lipase alpha/beta (DAGLα/β) and N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD)] and degrade [monoacylglycerol lipase (MAGL) and fatty acid amino hydrolase (FAAH)] eCB} were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system [glutamate synthesizing enzymes liver-type glutaminase isoform (LGA) and kidney-type glutaminase isoform (KGA), metabotropic glutamatergic receptor (mGluR3/5), NMDA-ionotropic glutamatergic receptor (NR1/2A/2B/2C) and AMPA-ionotropic receptor subunits (GluR1/2/3/4)] and the gene expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-arachidonylglycerol (2-AG) production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and

  11. Acute short-term dim light exposure can lower muscle strength endurance

    Arnold G. Nelson; Joke Kokkonen; Megan Mickenberg

    2015-01-01

    Background:Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light (i.e., 1 h) would have similar influence upon muscular endurance. Therefore this study compared the number of weighted knee extension lifts that could be done after spending 1 h in either dim or bright light. Methods:Participants (5 women, 11 men, college students 19-26 years) performed knee extension lifts to exhaustion with a load approximating 40%of their body weight. The lifts to exhaustion were measured immediately following 1 h of exposure to each of the following three con-ditions:dark (DL), room light (RL), and room light plus 5 mg melatonin (RLM). A minimum of 48 h separated each condition, and all par-ticipants started the exposures in a rested fed condition. Results:Average (±SD) number of knee extension lifts for RL (62.0 ± 22.0) was significantly ( p<0.05) greater than DL (51.4 ± 14.7) and RLM (57.8 ± 22.9). The number of RLM knee extension lifts was not significantly different from DL. Exposure to 1 h of dim light immediately prior to activity can result in a reduction in thigh muscle endurance. The decline in performance to short-term dim light exposure was similar to that found following longer-term exposure. Conclusion: It appears that light intensity can influence muscle endurance, however, at this time this effect cannot be directly related to endogenous melatonin production.

  12. Effect of acute ozone exposure on the proteinase-antiproteinase balance in the rat lung

    Lung disease may result from a persisting proteinase excess or a depletion of antiproteinase in pulmonary parenchyma. We investigated the in vivo effect of a 48-hr exposure to ozone at 0.5, 1.0, or 1.5 ppm on proteinase and antiproteinase activity of rat lungs. Elastase inhibitory capacities of serum, lung tissue, and airway washings were measured as indicators of antielastase activity. Trypsin inhibitory capacity was measured using an esterolytic procedure. Proteinase was measured as radioactive release from a 14C-globin substrate. The 48-hr exposures to O3 at levels up to 1 ppm produced concentration-dependent decreases of 35-80% of antiproteinase activities in serum and in lung tissue. However, exposure to 1.5 ppm O3 resulted in no decrease in antiproteinase activities. Acid proteinase activities (pH 4.2) were increased 65-120% by exposure to 1 or 1.5 ppm O3, which correlated with inflammatory cells noted histologically. At 1.5 ppm O3, pulmonary edema and hemorrhage were noted in histologic sections. These changes led to a flooding of the alveoli with up to 40 times normal protein levels and a greater than fivefold increase in airway antiproteinase. These data suggest that serum and soluble lung tissue antiproteinase activity decreased upon exposure to low levels of ozone. However, if O3 exposure is high enough to produce pulmonary hemorrhage, antiproteinase may increase following serum exudation. These changes may be important in the development of ozone-induced lung diseases, especially emphysema

  13. Neonatal Exposure to Parathion Alters Lipid Metabolism in Adulthood: Interactions with Dietary Fat Intake and Implications for Neurodevelopmental Deficits

    Lassiter, T. Leon; Ryde, Ian T.; Levin, Edward D.; Seidler, Frederic J; Slotkin, Theodore A.

    2010-01-01

    Organophosphates are developmental neurotoxicants but recent evidence also points to metabolic dysfunction. We determined whether neonatal parathion exposure in rats has long-term effects on regulation of adipokines and lipid peroxidation. We also assessed the interaction of these effects with increased fat intake. Rats were given parathion on postnatal days 1–4 using doses (0.1 or 0.2 mg/kg/day) that straddle the threshold for barely detectable cholinesterase inhibition and the first signs o...

  14. Improved analytical methods for perfluoroalkyl acids (PFAAs) and their precursors – a focus on human dietary exposure

    Ullah, Shahid

    2013-01-01

    Per- and polyfluoroalkyl substances are a large group of global environmental contaminants. They can be divided into two sub-groups, 1) perfluoroalkyl acids (PFAAs) and 2) so called precursors, i.e. compounds that can potentially be transformed to form PFAAs. PFAAs are today ubiquitous in wildlife and humans. Food and drinking water are assumed to be the dominant human exposure pathways for PFAAs. The main aim of this doctoral thesis was to develop highly sensitive and fully validated analyti...

  15. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures

  16. Altered Hippocampal Lipid Profile Following Acute Postnatal Exposure to Di(2-Ethylhexyl Phthalate in Rats

    Catherine A. Smith

    2015-10-01

    Full Text Available Slight changes in the abundance of certain lipid species in the brain may drastically alter normal neurodevelopment via membrane stability, cell signalling, and cell survival. Previous findings have demonstrated that postnatal exposure to di (2-ethylhexyl phthalate (DEHP disrupts normal axonal and neural development in the hippocampus. The goal of the current study was to determine whether postnatal exposure to DEHP alters the lipid profile in the hippocampus during postnatal development. Systemic treatment with 10 mg/kg DEHP during postnatal development led to elevated levels of phosphatidylcholine and sphingomyelin in the hippocampus of female rats. There was no effect of DEHP exposure on the overall abundance of phosphatidylcholine or sphingomyelin in male rats or of lysophosphatidylcholine in male or female rats. Individual analyses of each identified lipid species revealed 10 phosphatidylcholine and six sphingomyelin lipids in DEHP-treated females and a single lysophosphatidylcholine in DEHP-treated males with a two-fold or higher increase in relative abundance. Our results are congruent with previous work that found that postnatal exposure to DEHP had a near-selective detrimental effect on hippocampal development in males but not females. Together, results suggest a neuroprotective effect of these elevated lipid species in females.

  17. Renal effects of acute exposure to toluene. A controlled clinical trial

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

    1985-01-01

    Urinary excretion rates of beta 2-microglobulin and albumin were measured in 43 male printing trade workers and 43 age-matched male controls before and during exposure to toluene, 382 mg/m3, for 6 1/2 hours in a climate chamber. There were no significant changes in renal excretion rates of albumi...

  18. Electrocardiographic and autonomic effects of acute particulate matter (PM) exposure in a rat model of cardiomyopathy

    Human exposure to ambient PM from fossil-fuel emissions is linked to cardiovascular disease and death. This association strengthens in people with preexisting cardiac disease--especially heart failure (HF). Cardiomyopathy is the most common cause of heart failure. The mechanisms ...

  19. Combined exposure to simulated microgravity and acute or chronic radiation reduces neuronal network integrity and cell survival

    Benotmane, Rafi

    During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. This study aimed at assessing the effect of these combined conditions on neuronal network density, cell morphology and survival, using well-connected mouse cortical neuron cultures. To this end, neurons were exposed to acute low and high doses of low LET (X-rays) radiation or to chronic low dose-rate of high LET neutron irradiation (Californium-252), under the simulated microgravity generated by the Random Positioning Machine (RPM, Dutch space). High content image analysis of cortical neurons positive for the neuronal marker βIII-tubulin unveiled a reduced neuronal network integrity and connectivity, and an altered cell morphology after exposure to acute/chronic radiation or to simulated microgravity. Additionally, in both conditions, a defect in DNA-repair efficiency was revealed by an increased number of γH2AX-positive foci, as well as an increased number of Annexin V-positive apoptotic neurons. Of interest, when combining both simulated space conditions, we noted a synergistic effect on neuronal network density, neuronal morphology, cell survival and DNA repair. Furthermore, these observations are in agreement with preliminary gene expression data, revealing modulations in cytoskeletal and apoptosis-related genes after exposure to simulated microgravity. In conclusion, the observed in vitro changes in neuronal network integrity and cell survival induced by space simulated conditions provide us with mechanistic understanding to evaluate health risks and the development of countermeasures to prevent neurological disorders in astronauts over long-term space travels. Acknowledgements: This work is supported partly by the EU-FP7 projects CEREBRAD (n° 295552)

  20. Longitudinal tracking of cytokines after acute exposure to tuberculosis: association of distinct cytokine patterns with protection and disease development.

    Hussain, Rabia; Talat, Najeeha; Shahid, Firdaus; Dawood, Ghaffar

    2007-12-01

    Household contacts (HCs) of patients with tuberculosis (TB) are at higher risk of infection as well as the development of active disease. Longitudinal tracking of antigen-specific cytokines after acute exposure may significantly advance our understanding of the dynamic changes in cytokine patterns associated with disease establishment. To achieve this objective, we carried out a prospective cohort study with healthy HCs after exposure to TB. The patterns of cytokines (gamma interferon [IFN-gamma] and interleukin 10 [IL-10]) in response to mycobacterial antigens (culture filtrate [CF] proteins) and nonspecific mitogens (phytohemagglutinin [PHA] and lipopolysaccharide [LPS]) were assessed at 0, 6, 12, and 24 months after exposure. Seven of 109 (6.4%) HCs developed active disease. Six of the seven individuals were females, and active disease developed between 12 and 15 months after exposure in 5/20 families. The most significant findings were the exponential increases ( approximately 1,000-fold) in both the CF protein- and the PHA- or LPS-induced IFN-gamma/IL-10 ratio in healthy HCs (n = 26), which peaked at 12 months, compared to the levels in HCs who developed disease (n = 7), in whom relatively flat responses were observed during the 24-month period. Linear trends for 0 to 12 and 0 to 24 months for the CF protein-induced IFN-gamma/IL-10 ratio showed significant differences between the two groups, as determined by the use of the Mantel extension test for chi(2) analysis (odds ratio = 0.45; 95% confidence interval = 0.295 to 0.685; P = 0.0002). Our results strongly suggest that the magnitude of the IFN-gamma/IL-10 ratio at 12 months after exposure may be a critical determinant in the resolution of infection. These studies provide new insights into the cytokine responses associated with disease establishment or the resolution of infection after natural exposure to TB and have implications for TB control programs as well vaccine efficacy studies. PMID:17928427

  1. DNA adduct formation and oxidative stress in colon and liver of Big Blue rats after dietary exposure to diesel particles

    Dybdahl, Marianne; Risom, Lotte; Møller, Peter;

    2003-01-01

    in liver accompanied by enhanced vitamin C levels. In plasma, we found no significant effects on oxidative damage to proteins and lipids, antioxidant enzymes or vitamin C levels. Our data indicate that gastrointestinal exposure to DEP induces DNA adducts and oxidative stress resulting in DNA strand breaks...... on oxidative DNA damage (8-oxodG) in colon or liver DNA or in the urine. However, the mRNA expression of OGG1, encoding an enzyme involved in repair of 8-oxodG, was increased by DEP in both liver and colon. DNA adduct levels measured by 32P-post-labelling were elevated in colon and liver, and the expression...

  2. Induction of genomic instability after an acute whole-body exposure of mice to 56Fe ions

    Rithidech, Kanokporn; Supanpaiboon, Wisa; Whorton, Elbert

    Different types of galactic cosmic rays (GCR) are present in space and have large mass and energy (HZE particles). Among these, stripped 56 Fe ions are of major concern. Although HZE particles are approximately 1% of GCR, their contribution to health risk could be significant because of (1) their high linear energy transfer (LET) resulting in a larger amount of energy being deposited in the hit cells, and (2) the lack of information on the effectiveness of these particles in cancer induction. To better protect astronauts in space environments, it is essential that we improve our understanding of the 56 Fe-ion-induced damage associated with the increased risk of late occurring diseases (such as cancer). It has been well established that acute myeloid leukemia (AML) is one of the major malignancies associated with exposure to ionizing radiation in both human beings and in mice. It is therefore one of the most important cancers related to space flights. For these reasons, it is important to investigate 56 Fe ion-induced damage in in vivo systems, especially in those cells that are known to be at risk for health problems associated with radiation, such as hematopoietic cells, the known target cell for radiation-induced leukemia. Since in vivo studies of humans are not possible, animal studies are critically important. It has been widely suggested that elevation of delayed chromosomal damage (normally known as genomic instability) is associated with cancer risk. We therefore determined dose-response relationships for the frequencies of micronuclei (MN) in mouse blood erythrocytes as a measure of both initial radiation damage and the induction of genomic instability. The frequencies of MN were measured in mature normochromatic-erythrocytes (MN-NCEs) and immature polychromatic-erythrocytes (MN-PCEs). These measurements were made as a function of radiation dose, radiation quality, time after irradiation and the genetic background of exposed mice. Blood samples were

  3. Acute Exposure to Di(2-Ethylhexyl) Phthalate in Adulthood Causes Adverse Reproductive Outcomes Later in Life and Accelerates Reproductive Aging in Female Mice.

    Hannon, Patrick R; Niermann, Sarah; Flaws, Jodi A

    2016-03-01

    Humans are ubiquitously exposed to di(2-ethylhexyl) phthalate (DEHP), which is an environmental toxicant incorporated in consumer products. Studies have shown that DEHP targets the ovary to disrupt essential processes required for reproductive and nonreproductive health. Specifically, 10-day exposure to DEHP accelerates primordial follicle recruitment and disrupts estrous cyclicity in adult mice. However, it is unknown if these effects on folliculogenesis and cyclicity following acute DEHP exposure can have permanent effects on reproductive outcomes. Further, the premature depletion of primordial follicles can cause early reproductive senescence, and it is unknown if acute DEHP exposure accelerates reproductive aging. This study tested the hypothesis that acute DEHP exposure causes infertility, disrupts estrous cyclicity, alters hormone levels, and depletes follicle numbers by inducing atresia later in life, leading to accelerated reproductive aging. Adult CD-1 mice were orally dosed with vehicle or DEHP (20 μg/kg/day-500 mg/kg/day) daily for 10 days, and reproductive outcomes were assessed at 6 and 9 months postdosing. Acute DEHP exposure significantly altered estrous cyclicity compared to controls at 6 and 9 months postdosing by increasing the percentage of days the mice were in estrus and metestrus/diestrus, respectively. DEHP also significantly decreased inhibin B levels compared to controls at 9 months postdosing. Further, DEHP significantly increased the BAX/BCL2 ratio in primordial follicles leading to a significant decrease in primordial and total follicle numbers compared to controls at 9 months postdosing. Collectively, the adverse effects present following acute DEHP exposure persist later in life and are consistent with accelerated reproductive aging. PMID:26678702

  4. Effect of continuous exposure to apomorphine and acute exposure to fluphenazine-N-mustard on dopaminergic behavior and radioligand binding in supersensitive mice

    Winkler, J.D.

    1987-01-01

    Mice with unilateral, 6-hydroxydopamine-induced lesions of the corpus striatum were exposed to continuous infusion of apomorphine via a subcutaneously implanted osmotic pump. The turning response of these mice when challenged with an acute injection of apomorphine was significantly reduced at one day after chronic implantation and was totally absent at two and four days after implantation. This effect of continuous exposure to apomorphine was found to be concentration- and time-dependent as well as reversible when the implant was removed. Mice tolerant to apomorphine were cross-tolerant to the rotational effects of the D{sub 1} dopaminergic agonist SKF 38393 and the D{sub 2} dopaminergic agonist Ly 171555, but not to amphetamine. Continuous exposure to apomorphine resulted in a decrease in the binding of ({sup 3}H)spiroperidol (D{sub 2} sites) by 44%, whereas the binding of ({sup 3}H)SCH 23390 (D{sub 1} sites) was not affected. Fluphenazine-N-mustard (FNM) has been shown to bind irreversibly to dopaminergic sites. Experiments using varying doses of FNM demonstrated that FNM inhibited Ly 171555-induced rotational behavior at doses ten fold lower than those required to block rotations induced by SKF 38393. In vitro, FNM inhibited the specific binding of ({sup 3}H) spiroperidol at concentrations ten fold lower than those required to inhibit the binding of ({sup 3}H)Sch23390. In vivo, FNM inhibited the binding of ({sup 3}H) spiroperidol measured ex vivo, but did not inhibit the binding of ({sup 3}H) Sch 23390, even when given in doses as high as 100 mg/kg. These studies indicate that FNM was approximately ten times more potent at inhibiting D{sub 2} than D{sub 1} mediated behavior and at displacing D{sub 2} versus D{sub 1} ligands, suggesting that FNM may be useful for studying and differentiating D{sub 2} and D{sub 1} mediated events.

  5. Diarrheal Diseases - Acute and Chronic

    ... and drinking contaminated or raw foods and beverages. Screening/Diagnosis Most episodes of acute diarrhea resolve quickly without antibiotic therapy and with simple dietary modifications. See a ...

  6. Excretion of N-mononitrosopiperazine after low level exposure to piperazine in air: effects of dietary nitrate and ascorbate

    Bellander, T.; Osterdahl, B.G.; Hagmar, L.

    1988-04-01

    The secondary amine piperazine may be nitrosated in vivo, following oral intake or occupational exposure by inhalation. The suspected carcinogen N-mononitrosopiperazine could be formed in the human stomach, and in part excreted in the urine. In this study, 0.4 microgram N-mononitrosopiperazine, determined by gas chromatography-Thermal Energy Analysis, was observed in the urine in one of four volunteers, at an experimental exposure by inhalation of 0.3 mg piperazine/m3. The intake of spinach and beetroot caused an increased nitrosation of piperazine, and up to 1.7 microgram N-mononitrosopiperazine was excreted in the urine in the four individuals. This excretion indicates that about 5% of the absorbed piperazine dose was converted to N-mononitrosopiperazine. With the same nitrate-rich diet, but with the addition of citrus fruits and fresh vegetables, the highest excretion was 0.6 microgram N-mononitrosopiperazine. The excretion was significantly correlated with the ratio between the maximum level of nitrite in saliva and the ascorbate level in plasma. There was also a significant interindividual variation. N,N'-Dinitrosopiperazine was not found in any sample of urine.

  7. Dietary exposure to volatile and non-volatile N-nitrosamines from processed meat products in Denmark

    Herrmann, Susan Strange; Duedahl-Olesen, Lene; Christensen, Tue;

    2015-01-01

    carcinogenicity for the majority of the non-volatile NA (NVNA) remains to be elucidated. Danish adults (15–75 years) and children (4–6 years) consume 20 g and 16 g of processed meat per day (95th percentile), respectively. The consumption is primarily accounted for by sausages, salami, pork flank (spiced and......Recent epidemiological studies show a positive association between cancer incidence and high intake of processed meat. N-nitrosamines (NAs) in these products have been suggested as one potential causative factor. Most volatile NAs (VNAs) are classified as probable human carcinogens, whereas the...... boiled) and ham. This consumption results in an exposure to NVNA of 33 and 90 ng kg bw−1 day−1 for adults and children, respectively. The exposure to VNA is significantly lower amounting to 0.34 and 1.1 ng kg bw−1 day−1 for adults and children, respectively. Based on a BMDL10 of 29 µg kg bw−1 day−1 a MOE...

  8. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    Fabrikant, J.I.

    1981-05-01

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures. (ACR)

  9. Arsenic (As Contamination in Different Food and Dietary Samples from Several Districts of Bangladesh and Arsenic (As Detection, Mitigation and Toxicity Measurement and impact of Dietary Arsenic Exposure on Human Health

    M A Awal

    2010-10-01

    Full Text Available Objective: To determine the level of arsenic concentration in vegetables and other food categories in three selected areas of Pabna district and to estimate quantitatively the dietary arsenic exposure in one of the arsenic contaminated areas of Bangladesh.Materials and Methods: The study was conducted in CharRuppur, Char mirkamari and Lakshmikunda village of IshwardiUpzila in Pabna district. Ishwardi (Town consists of 12 wardsand 37 mahallas. Arsenic was detected in the ADM Lab,Department of Pharmacology, Bangladesh Agricultural University, Mymensingh with Hydride Generation Atomic Absorption Spectrophotometer (HG-AAS; PG-990, PG Instruments Ltd. UK. Arsenic was detected by forming AsH3 at below pH 1.0 after the reaction of As with a solution of sodiumborohydride (NaBH4, sodium hydroxide (NaOH, M=40,000g/mol, and 10% HCl. In this test, standard was maintained asAsV ranging from 0 to 12.5 μg/L.Results: A total of 120 vegetable samples, 15 rice samples and15 fish samples were collected from five different markets ofthree different villages of Pabna district and were tested forarsenic concentration. Findings demonstrated that the mean concentration of As in leafy vegetables (0.52 μg g-1 was significantly higher compared to those found in fruity (0.422μg g-1 and root & tuber vegetables (0.486 μg g-1.Conclusion: Underground Contaminated water was the major source for the As contamination of various products in Pabna.The arsenic levels were found higher among the leafy vegetables samples in comparison to fruit and root & tuber vegetables. Further studies will be conducted to search the genetic risk factors of arsenic toxicity in the population of the mostly affected people.

  10. Assessment of human health hazards associated with the dietary exposure to organic and inorganic contaminants through the consumption of fishery products in Spain.

    Rodríguez-Hernández, Ángel; Camacho, María; Henríquez-Hernández, Luis A; Boada, Luis D; Ruiz-Suárez, Norberto; Valerón, Pilar F; Almeida González, Maira; Zaccaroni, Annalisa; Zumbado, Manuel; Luzardo, Octavio P

    2016-07-01

    In this work we have evaluated the potential carcinogenic and acutely toxic risks associated to the exposure to highly prevalent organic and inorganic contaminants through the consumption of fishery products by the Spanish population. The concentrations of 8 organochlorine pesticides (OCPs), 18 polychlorinated biphenils (PCBs), 7 polycyclic aromatic hydrocarbons (expressed as benzo[a]pyrene toxic equivalents (B[a]Peq)), and three inorganic toxic elements [arsenic (As), cadmium (Cd), and mercury (Hg)] were determined in 93 samples of the most consumed species of white fish, blue fish, cephalopods and seafood species, which were acquired directly in markets and supermarkets in the Canary Islands, Spain. The chemical concentration data were combined with the pattern of consumption of these foodstuffs in order to calculate the daily intake of these contaminants, and on this basis the risk quotients for carcinogenicity and acute toxicity were determined for Spanish adults and children. Our results showed that the daily intake of OCPs, PCBs and B[a]Peq, which is associated to blue fish consumption was the highest within the fish group. The estimated intake of pollutants can be considered low or very low for the individual contaminants, when compared to reference values, except in the case of HCB and As. All the estimated intakes were below the reported Tolerable Daily Intakes. Considering the additive effects of multiple contaminants, the risk of acute toxic effects can also be considered as low or very low. However, our results reflect that the current consumption of white fish in adults and children, and also the blue fish in the case of adults, poses a moderate carcinogenic risk to Spanish consumers, mainly related to their concentrations of As. The conclusions of this research may be useful for the design of appropriate risk communication campaigns. PMID:27060748

  11. Acute and sub-lethal exposure to copper oxide nanoparticles causes oxidative stress and teratogenicity in zebrafish embryos.

    Ganesan, Santhanamari; Anaimalai Thirumurthi, Naveenkumar; Raghunath, Azhwar; Vijayakumar, Savitha; Perumal, Ekambaram

    2016-04-01

    Nano-copper oxides are a versatile inorganic material. As a result of their versatility, the immense applications and usage end up in the environment causing a concern for the lifespan of various beings. The ambiguities surround globally on the toxic effects of copper oxide nanoparticles (CuO-NPs). Hence, the present study endeavored to study the sub-lethal acute exposure effects on the developing zebrafish embryos. The 48 hpf LC50 value was about 64 ppm. Therefore, we have chosen the sub-lethal dose of 40 and 60 ppm for the study. Accumulation of CuO-NPs was evidenced from the SEM-EDS and AAS analyzes. The alterations in the AChE and Na(+)/K(+)-ATPase activities disrupted the development process. An increment in the levels of oxidants with a concomitant decrease in the antioxidant enzymes confirmed the induction of oxidative stress. Oxidative stress triggered apoptosis in the exposed embryos. Developmental anomalies were observed with CuO-NPs exposure in addition to oxidative stress in the developing embryos. Decreased heart rate and hatching delay hindered the normal developmental processes. Our work has offered valuable data on the connection between oxidative stress and teratogenicity leading to lethality caused by CuO-NPs. A further molecular mechanism unraveling the uncharted connection between oxidative stress and teratogenicity will aid in the safe use of CuO-NPs. PMID:26493272

  12. Study on the therapeutic effect of cytokine on acute radiation syndrome induced by 60Co γ ray exposure

    Objective: To examine the therapeutic effect of combined administration of rhIL-11 and rhG-CSF on acute radiation syndrome induced by 60Coγ ray exposure in beagles. Methods: Sixteen beagles were randomly divided into the control (n=5), symptomatic treatment group (n=5) and cytokine treatment group (n=6). All the beagles in the three groups were exposed to the whole-body irradiation of 60Co γ ray at a dose of 4.5 Gy. The animals in the second group accepted active symptomatic treatment. The animals in the cytokine treatment group were sub-cutaneously administered rhIL -11 and rhG -CSF besides active symptomatic treatment. Hemogram of peripheral blood, pristine apoptosis and necrosis ratio of nucleated cells, the content of IL-2 and IFN-γ in plasma and formation of bone marrow were used to evaluate the therapeutic effect. Results: In the cytokine treatment group, the animal' survival rate 45 days after exposure was increased and hemogram of peripheral blood was improved significantly. The rate of pristine apoptosis and necrosis of nucleated cell declined obviously. Early, the content of both IL-2 and IFN-γ in plasma was up significantly, then the content of IL-2 rapidly descended, but that of IFN-γ was relatively stable. Conclusion: The combined administration of rhIL-11 and rhG-CSF significantly improved the recovery of hematopoietic and immunological function. (authors)

  13. Use of a custom RT-PCR array to analyze toxicity pathways at different life stages in Brown Norway Rat Brain following acute Toluene exposure.

    To investigate the contribution of different life stages on response to toxicants, we utilized a custom designed RT-PCR array to examine the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.65 or 1.0 glkg) in the brains of ma1e Brown Norwa...

  14. Intermittent Exposure to Social Defeat and Open-field Test in Rats : Acute and Long-term Effects on ECG, Body Temperature and Physical Activity

    Sgoifo, Andrea; Pozzato, Chiara; Meerlo, Peter; Costoli, Tania; Manghi, Massimo; Stilli, Donatella; Olivetti, Giorgio; Musso, Ezio

    2002-01-01

    This study investigated the effects of exposure to an intermittent homotypic stressor on: (i) habituation of acute autonomic responsivity (i.e. cardiac sympathovagal balance and susceptibility to arrhythmias), and (ii) circadian rhythmicity of heart rate, body temperature, and physical activity. Aft

  15. Integrated risk analysis for acute and chronic exposure to toxic chemicals

    Gurjar, B.R.; Mohan, Manju

    2003-10-01

    The traditional practice to assess and evaluate different types of risk in isolation to each other are liable to give erroneous results. Integrated risk assessment is an answer to overcome this problem. This paper presents the cumulative or integrated assessment of acute risk posed by accidental release of hazardous chemical (e.g. chlorine) and chronic risk induced by toxic chemicals (e.g. cadmium, chromium and nickel) present in the ambient environment. The present study has been carried out in a most simplified way to demonstrate and appreciate the broader context of integrated risk analysis (IRA). It has been observed that the inclusion of background risk factors (BRF) in individual risk factors (IRF) related to an industry may significantly alter the siting and planning strategies of that industry.

  16. DNA strand breaks, acute phase response and inflammation following pulmonary exposure by instillation to the diesel exhaust particle NIST1650b in mice

    Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T.;

    2015-01-01

    the alkaline comet assay as DNA strand breaks in BAL cells, lung and liver tissue. The pulmonary acute phase response was analysed by Saa3 mRNA levels by real-time quantitative polymerase chain reaction. Instillation of DEP induced a strong neutrophil influx 1 and 3 days, but not 28 days post......We investigated the inflammatory response, acute phase response and genotoxic effect of diesel exhaust particles (DEPs, NIST1650b) following a single intratracheal instillation. C57BL/6J BomTac mice received 18, 54 or 162 µg/mouse and were killed 1, 3 and 28 days post-exposure. Vehicle controls and...... inflammation but long-lasting pulmonary acute phase response as well as genotoxicity in lung tissue 28 days post-exposure. The observed long-term pulmonary genotoxicity by DEP was less than the previously observed genotoxicity for CB using identical experimental set-up....

  17. Harmonisation of food consumption data format for dietary exposure assessments of chemicals analysed in raw agricultural commodities

    Boon, Polly E.; Ruprich, Jiri; Petersen, Annette;

    2009-01-01

    in RACs at a European level. In this approach, consumption data needs to be converted to edible part of RAC (e-RAC) level using a RAC conversion database. To subsequently use this data in exposure assessments, both e-RACs and RACs analysed in chemical control programmes should be classified via a...... uniform system. Furthermore, chemical concentrations in RACs may need to be converted to e-RAC level using processing factors. To illustrate the use of this approach, we describe how the Dutch RAC conversion database was used to convert consumption data of four national consumption surveys to e-RAC level......, and the use of the FAO/WHO Codex Classification system of Foods and Animal Feeds to harmonise the classification. We demonstrate that this approach works well for pesticides and glycoalkaloids, and is an essential step forward in the harmonisation of risk assessment procedures within Europe when...

  18. Transcriptional response of rat frontal cortex following acute In Vivo exposure to the pyrethroid insecticides permethrin and deltamethrin

    Tornero-Velez Rogelio

    2008-11-01

    Full Text Available Abstract Background Pyrethroids are neurotoxic pesticides that interact with membrane bound ion channels in neurons and disrupt nerve function. The purpose of this study was to characterize and explore changes in gene expression that occur in the rat frontal cortex, an area of CNS affected by pyrethroids, following an acute low-dose exposure. Results Rats were acutely exposed to either deltamethrin (0.3 – 3 mg/kg or permethrin (1 – 100 mg/kg followed by collection of cortical tissue at 6 hours. The doses used range from those that cause minimal signs of intoxication at the behavioral level to doses well below apparent no effect levels in the whole animal. A statistical framework based on parallel linear (SAM and isotonic regression (PIR methods identified 95 and 53 probe sets as dose-responsive. The PIR analysis was most sensitive for detecting transcripts with changes in expression at the NOAEL dose. A sub-set of genes (Camk1g, Ddc, Gpd3, c-fos and Egr1 was then confirmed by qRT-PCR and examined in a time course study. Changes in mRNA levels were typically less than 3-fold in magnitude across all components of the study. The responses observed are consistent with pyrethroids producing increased neuronal excitation in the cortex following a low-dose in vivo exposure. In addition, Significance Analysis of Function and Expression (SAFE identified significantly enriched gene categories common for both pyrethroids, including some relating to branching morphogenesis. Exposure of primary cortical cell cultures to both compounds resulted in an increase (~25% in the number of neurite branch points, supporting the results of the SAFE analysis. Conclusion In the present study, pyrethroids induced changes in gene expression in the frontal cortex near the threshold for decreases in ambulatory motor activity in vivo. The penalized regression methods performed similarly in detecting dose-dependent changes in gene transcription. Finally, SAFE analysis of

  19. Concentrations of polybrominated diphenyl ethers (PBDEs) in central air-conditioner filter dust and relevance of non-dietary exposure in occupational indoor environments in Greece

    Polybrominated Diphenyl Ethers (PBDEs) are ubiquitous in the indoor environment owing to their use in consumer products and various studies around the world have found higher concentrations indoors than outdoors. Central air conditioner (A/C) systems have been widely used in many workplaces, therefore, studying of PBDEs in central A/C filter dust is useful to better understand the occurrences and health implications of PBDEs in indoor environments. The present study examined the occurrence of PBDEs in central A/C filter dust collected from various workplaces (n = 20) in Thessaloniki, Greece. The sum concentrations of 21 target congeners (∑21PBDE) in A/C dust ranged between 84 and 4062 ng g−1 with a median value of 1092 ng g−1, while BDE-209 was found to be the most abundant BDE congener. The daily intake via dust ingestion of PBDEs estimated for the employees of the occupational settings ranged from 3 to 45 ng day−1 (median 12 ng day−1). - Highlights: • PBDEs were investigated in dust of A/C filters in occupational settings in Thessaloniki, Greece. • BDE-209 was found to be the most abundant BDE congener. • High levels of PBDEs were found in a newspaper building, internet cafes and electronic shops. • PBDEs were attributable to the extensive presence and/or usage of electronic devices. • Exposure of employees to PBDEs via indoor dust ingestion was estimated at 12 ng day−1. - PBDEs were for the first time measured in dust from central A/C filters in workplaces of Greece and their concentrations were used to estimate the non-dietary human exposure

  20. Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

    Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

  1. Examination of Single-Walled Carbon Nanotubes Uptake and Toxicity from Dietary Exposure: Tracking Movement and Impacts in the Gastrointestinal System

    Joseph H. Bisesi

    2015-06-01

    Full Text Available Previous studies indicate that exposure of fish to pristine single-walled carbon nanotubes (SWCNTs by oral gavage, causes no overt toxicity, and no appreciable absorption has been observed. However, in the environment, SWCNTs are likely to be present in dietary sources, which may result in differential impacts on uptake and biological effects. Additionally, the potential of these materials to sorb nutrients (proteins, carbohydrates, and lipids while present in the gastrointestinal (GI tract may lead to nutrient depletion conditions that impact processes such as growth and reproduction. To test this phenomenon, fathead minnows were fed a commercial diet either with or without SWCNTs for 96 h. Tracking and quantification of SWCNTs using near-infrared fluorescence (NIRF imaging during feeding studies showed the presence of food does not facilitate transport of SWCNTs across the intestinal epithelia. Targeting genes shown to be responsive to nutrient depletion (peptide transporters, peptide hormones, and lipases indicated that pept2, a peptide transporter, and cck, a peptide hormone, showed differential mRNA expression by 96 h, a response that may be indicative of nutrient limitation. The results of the current study increase our understanding of the movement of SWCNTs through the GI tract, while the changes in nutrient processing genes highlight a novel mechanism of sublethal toxicity in aquatic organisms.

  2. Mitochondrial damage: An important mechanism of ambient PM2.5 exposure-induced acute heart injury in rats

    Highlights: • PM2.5 induces heart mitochondrial morphological damage of rats. • Mitochondrial fission/fusion gene expression is important regulation mechanism. • Proinflammatoy cytokine level changes are accompanied with mitochondrial damage. • Alterations in oxidative stress and calcium homeostasis are focused on. - Abstract: Epidemiological studies suggested that ambient fine particulate matter (PM2.5) exposure was associated with cardiovascular disease. However, the underlying mechanism, especially the mitochondrial damage mechanism, of PM2.5-induced heart acute injury is still unclear. In this study, the alterations of mitochondrial morphology and mitochondrial fission/fusion gene expression, oxidative stress, calcium homeostasis and inflammation in hearts of rats exposed to PM2.5 with different dosages (0.375, 1.5, 6.0 and 24.0 mg/kg body weight) were investigated. The results indicated that the PM2.5 exposure induced pathological changes and ultra-structural damage in hearts such as mitochondrial swell and cristae disorder. Furthermore, PM2.5 exposure significantly increased specific mitochondrial fission/fusion gene (Fis1, Mfn1, Mfn2, Drp1 and OPA1) expression in rat hearts. These changes were accompanied by decreases of activities of superoxide dismutase (SOD), Na+K+-ATPase and Ca2+-ATPase and increases of levels of malondialdehyde (MDA), inducible nitric oxide synthase (iNOS) and nitric oxide (NO) as well as levels of pro-inflammatory mediators including TNF-α, IL-6 and IL-1β in rat hearts. The results implicate that mitochondrial damage, oxidative stress, cellular homeostasis imbalance and inflammation are potentially important mechanisms for the PM2.5-induced heart injury, and may have relations with cardiovascular disease

  3. Comparison of two pre-exposure treatment regimens in acute organophosphate (paraoxon) poisoning in rats: Tiapride vs. pyridostigmine

    Recently, the FDA approved the medical use of oral pyridostigmine as prophylactic treatment of possible nerve agent exposure: the concept is to block the cholinesterase transitorily using the carbamate (pyridostigmine) in order to deny access to the active site of the enzyme to the irreversible inhibitor (nerve agent) on subsequent exposure. We have shown previously that tiapride is in vitro a weak inhibitor of acetylcholinesterase and that in rats administration of tiapride before the organophosphate paraoxon significantly decreases mortality. The purpose of the present study was to compare tiapride- and pyridostigmine-based pretreatment strategies, either alone or in combination with pralidoxime reactivation, by using a prospective, non-blinded study in a rat model of acute high-dose paraoxon exposure. Groups 1-6 received 1 μMol paraoxon (∼ LD75) groups 2-6 received in addition: G2 50 μMol tiapride 30 min before paraoxon; G3 50 μMol tiapride 30 min before paraoxon and 50 μMol pralidoxime 1 min after paraoxon; G4 1 μMol pyridostigmine 30 min before paraoxon; G5 1 μMol pyridostigmine 30 min before paraoxon and 50 μMol pralidoxime 1 min after paraoxon; G6 50 μMol pralidoxime 1 min after paraoxon; Mortality data were compared using Kaplan-Meier plots and logrank tests. Mortality is statistically significantly influenced by all treatment strategies. Tiapride pretreatment followed by pralidoxime treatment (G3) is aux par with pyridostigmine pretreatment followed by pralidoxime treatment (G5). Tiapride pretreatment only (G2) is inferior to pyridostigmine pretreatment only (G4). The best results are achieved with pyridostigmine pretreatment only or pralidoxime treatment only (G4 and G6)

  4. Acute respiratory effects in the potato processing industry due to a bioaerosol exposure.

    Hollander, A; Heederik, D.; Kauffman, H.

    1994-01-01

    The relation between bioaerosol exposure in the potato starch industry and work related respiratory symptoms is described. One group of workers was exposed to high dust concentrations (geometric mean up to 56.0 mg/m3) with low endotoxin and antigen concentrations (geometric mean up to 12.6 ng/m3 and 90 relative antigen units (RAU) per m3). A second group was exposed to low dust concentrations (geometric mean up to 3.9 mg/m3), but the endotoxin and antigen concentrations were high (geometric m...

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

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

    2014-02-01

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

  6. Intercomparison of model predictions of tritium concentrations in soil and foods following acute airborne HTO exposure

    This paper describes the results of a model intercomparision exercise for predicting tritium transport through foodchains. Modellers were asked to assume that farmland was exposed for one hour to an average concentration in air of 104 MBq tritium m-3. They were given the initial soil moisture content and 30 days of hourly averaged historical weather and asked to predict HTO and OBT concentrations in foods at selected times up to 30 days later when crops were assumed to be harvested. Two fumigations were postulated, one at 10.00 h (i.e., in day-light), and the other at 24.00 h (i.e., in darkness).Predicted environmental media concentrations after the daytime exposure agreed within an order of magnitude in most cases. Important sources of differences were variations in choices of numerical values for transport parameters. The different depths of soil layers used in the models appeared to make important contributions to differences in predictions for the given scenario. Following the night-time exposure, however, greater differences in predicted concentrations appeared. These arose largely because of different ways key processes were assumed to be affected by darkness. Uptake of HTO by vegetation and the rate it is converted to OBT were prominent amongst these processes. Further research, experimental data and modelling intercomparisons are required to resolve some of these issues. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

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

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

    2013-09-01

    Millions of people witnessed early, repeated television coverage of the September 11 (9/11), 2001, terrorist attacks and were subsequently exposed to graphic media images of the Iraq War. In the present study, we examined psychological- and physical-health impacts of exposure to these collective traumas. A U.S. national sample (N = 2,189) completed Web-based surveys 1 to 3 weeks after 9/11; a subsample (n = 1,322) also completed surveys at the initiation of the Iraq War. These surveys measured media exposure and acute stress responses. Posttraumatic stress symptoms related to 9/11 and physician-diagnosed health ailments were assessed annually for 3 years. Early 9/11- and Iraq War-related television exposure and frequency of exposure to war images predicted increased posttraumatic stress symptoms 2 to 3 years after 9/11. Exposure to 4 or more hr daily of early 9/11-related television and cumulative acute stress predicted increased incidence of health ailments 2 to 3 years later. These findings suggest that exposure to graphic media images may result in physical and psychological effects previously assumed to require direct trauma exposure. PMID:23907546

  8. 厦门市居民食品塑化剂暴露风险评估%Exposure risk assessment of plasticizer in dietary food in Xiamen

    庄群瑛; 杨月; 苏艳华; 吕婵雯; 王素梅; 喻欢; 秦梦婷; 李燕妮; 赵本华

    2014-01-01

    )均小于美国环境保护署提出的经口摄入参考剂量(RfD)(800、100、20 μg· kg-1·d-1),风险指数分别为0.02%、4.20%、90.50%.水产品为DEP膳食暴露的首要来源,暴露量和贡献率分别为0.18 μg·kg-1·d-1、94.74%.蔬菜类为DBP和DEHP的主要暴露来源,暴露量和贡献率分别为1.48 μg·kg-1·d-1、35.24%和6.07 μg· kg-1·d-1、33.54%.结论 厦门市居民膳食整体处于安全水平,存在一定程度的DEHP暴露风险.%Objective To understand the dietary consumption of residents in Xiamen and the content of phthalic acid esters (PAEs) in food,and to assess the plasticizer exposure risk of diet in Xiamen.Methods The survey was conducted by stratified cluster random sampling method in Xiamen from September to October in 2010.According to the Xiamen administrative division,six neighborhood communities were selected as sampling units,then 25 families were randomly chosen from each sampling units.From the above 150 families,the permanent residents over the age of six were permitted to our study.The survey included 495 residents totally.These participants' information,such as basic personal information,physical activity levels,meal frequency and the average consumption of 33 kinds of food in 13 categories were collected using questionnaires.Thirteen categories included cereal and tubers,beans,vegetables,fungi and algae,fruits,dairy products,meat,seafood,eggs,snacks,beverages,cooking oil and spices.The height and weight of residents were measured and the average daily dietary intake was calculated.Thirty-three kinds of food in 13 categories were collected in supermarkets in Xiamen.According to the annual sales ranking,the top three-five brands of each kinds of food were selected and numbered,then two or three brands were chosen by random number table method from them; three completely individual packed samples in the same batch of each brand were detected; 243 samples were included in our study.100-500 g solid

  9. Urinary and dietary analysis of 18,470 bangladeshis reveal a correlation of rice consumption with arsenic exposure and toxicity.

    Stephanie Melkonian

    Full Text Available BACKGROUND: We utilized data from the Health Effects of Arsenic Longitudinal Study (HEALS in Araihazar, Bangladesh, to evaluate the association of steamed rice consumption with urinary total arsenic concentration and arsenical skin lesions in the overall study cohort (N=18,470 and in a subset with available urinary arsenic metabolite data (N=4,517. METHODS: General linear models with standardized beta coefficients were used to estimate associations between steamed rice consumption and urinary total arsenic concentration and urinary arsenic metabolites. Logistic regression models were used to estimate prevalence odds ratios (ORs and their 95% confidence intervals (CIs for the associations between rice intake and prevalent skin lesions at baseline. Discrete time hazard models were used to estimate discrete time (HRs ratios and their 95% CIs for the associations between rice intake and incident skin lesions. RESULTS: Steamed rice consumption was positively associated with creatinine-adjusted urinary total arsenic (β=0.041, 95% CI: 0.032-0.051 and urinary total arsenic with statistical adjustment for creatinine in the model (β=0.043, 95% CI: 0.032-0.053. Additionally, we observed a significant trend in skin lesion prevalence (P-trend=0.007 and a moderate trend in skin lesion incidence (P-trend=0.07 associated with increased intake of steamed rice. CONCLUSIONS: This study suggests that rice intake may be a source of arsenic exposure beyond drinking water.

  10. Multiple biomarkers responses in juvenile rainbow trout, Oncorhynchus mykiss, after acute exposure to a fungicide propiconazole.

    Li, Zhi-Hua; Zlabek, Vladimir; Velisek, Josef; Grabic, Roman; Machova, Jana; Kolarova, Jitka; Li, Ping; Randak, Tomas

    2013-03-01

    In this study, the toxic effects of propiconazole (PCZ), a triazole fungicide present in aquatic environment, were studied in juvenile rainbow trout, Oncorhynchus mykiss, by acute toxicity test with the concentration of 5.04 mg/L (96 h LC50). Morphological indices, hematological parameters, liver xenobiotic-metabolizing response, and tissue antioxidant status were evaluated. Compared with the control group, fish exposed to PCZ showed significantly higher Leuko, PCV, MCHC, and hepatic EROD, and significantly lower MCV. CF and HSI were not significantly different among groups. SOD, CAT, GPx, and GR activities increased significantly in liver of experimental groups, but decreased significantly in gill. In general, antioxidant enzyme activity in intestine was less evident than in liver. Oxidative stress indices (levels of LPO and CP) were significantly higher in gill. Additionally, through chemometrics of all parameters measured in this study, two groups with 67.29% of total accumulated variance were distinguished. In short, the physiological and biochemical responses in different tissues of fish indicated that PCZ-induced the stressful environmental conditions. But according to PCZ residual status in the natural environment, more long-term experiments at lower concentrations will be necessary in the future. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013. PMID:21384499

  11. Epigenetic and phenotypic changes result from a continuous pre and post natal dietary exposure to phytoestrogens in an experimental population of mice

    Sabat Pablo

    2008-09-01

    Full Text Available Abstract Background Developmental effects of exposure to endocrine disruptors can influence adult characters in mammals, but could also have evolutionary consequences. The aim of this study was to simulate an environmental exposure of an experimental population of mice to high amounts of nutritional phytoestrogens and to evaluate parameters of relevance for evolutionary change in the offspring. The effect of a continuous pre- and post-natal exposure to high levels of dietary isoflavones was evaluated on sexual maturity, morphometric parameters and DNA methylation status in mice. Adult mice male/female couples were fed ad libitum either with control diet (standard laboratory chow or ISF diet (control diet plus a soy isoflavone extract at 2% (w/w that contained the phytoestrogens genistein and daidzein. In the offspring we measured: i the onset of vaginal opening (sexual maturation in females, ii weight and size in all pups at 7, 14, 21 and 42 days post-natal (dpn and iii DNA methylation patterns in skeletal α-actin (Acta1, estrogen receptor-α and c-fos in adults (42 dpn. Results Vaginal opening was advanced in female pups in the ISF group, from 31.6 ± 0.75 dpn to 25.7 ± 0.48. No differences in size or weight at ages 7, 14 or 21 dpn were detected between experimental groups. Nevertheless, at age 42 dpn reduced size and weight were observed in ISF pups, in addition to suppression of normal gender differences in weight seen in the control group (males heavier that females. Also, natural differences seen in DNA methylation at Acta1 promoter in the offspring originated in the control group were suppressed in the ISF group. Acta1 is known to be developmentally regulated and related to morphomotric features. Conclusion This study demonstrates in mammals that individuals from a population subjected to a high consumption of isoflavones can show alterations in characters that may be of importance from an evolutionary perspective, such as epigenetic and

  12. Early biochemical biomarkers for zinc in silver catfish (Rhamdia quelen) after acute exposure.

    Leitemperger, Jossiele; Menezes, Charlene; Santi, Adriana; Murussi, Camila; Lópes, Thais; Costa, Maiara; Nogueira, Lygia Sega; Loro, Vania Lucia

    2016-06-01

    Contamination of aquatic ecosystems by metals causes various biochemical changes in aquatic organisms, and fish are recognized as indicators of environmental quality. Silver catfish were exposed to six concentrations of zinc (Zn): 1.0, 2.5, 5.0, 7.5, 10.0 and 12.5 mg/L for 96 h to determine the mean lethal concentration (LC50). The value obtained was 8.07 mg/L. In a second experiment, fish were exposed to concentrations of 1.0 or 5.0 mg/L Zn and a control for 96 h. Afterward, the tissues were collected for biochemical analysis. Lipid peroxidation, as indicated by thiobarbituric acid-reactive substance (TBARS), decreased in the liver and brain for all Zn concentrations tested, while in the gills TBARS levels increased at 1.0 mg/L and declined at 5.0 mg/L. Zn increased protein carbonyls in the muscle of silver catfish and decreased it in the other tissues. The enzyme superoxide dismutase increased in both exposed groups. However, catalase did not change. Glutathione S-transferase decreased in the liver and increased in the gills (1.0 mg/L), muscle (5.0 mg/L) and brain (1.0 and 5.0 mg/L). Nonprotein thiols changed only in brain and muscle tissue. Zn exposure inhibited acetylcholinesterase (AChE) activity in the brain at both concentrations tested, but did not change it in muscle. Exposure to Zn inhibited the activity of Na(+)/K(+)-ATPase in the gills and intestine at both concentrations tested. Our results demonstrate that Zn alters biochemical parameters in silver catfish and that some parameters such as AChE and Na(+)/K(+)-ATPase could be considered as early biomarkers of waterborne Zn toxicity. PMID:26744269

  13. Atrazine in sub-acute exposure results in sperm DNA disintegrity and nuclear immaturity in rats

    Rajab-Ali Sadrkhanloo

    2012-03-01

    Full Text Available This study was designed to evaluate the detrimental effect of atrazine (ATR on germinal epitheliums (GE cytoplasmic carbohydrate (CH and unsaturated fatty acids (UFA ratio and to clarify the effect of ATR on serum levels of FSH, LH, testosterone and inhibin-B (INH-B. The impact of ATR exposure on total antioxidant capacity (TAC, sperm DNA packing and integrity were also investigated. Seventy two Wistar rats were used. The rats in control group received vehicle and the animals in test groups received 100, 200 and 300 mg kg-1 BW of ATR orally on daily bases for 12, 24 and 48 days. In ATR-received groups the spermatogenesis cell were presented with dense reactive sites for lipidophilic staining associated with faint cytoplasmic CH accumulation. Dissociated germinal epithelium, negative tubular and repopulation indexes were manifested. The serum levels of testosterone, FSH, LH and INH-B decreased by 85% after 48 days exposure to high dose of ATR. TAC was reduced in a time- and dose-dependent manner. The sperm DNA damage was marked in animals which exposed to high dose of ATR (72.50 ± 2.25% and the percentage of nuclear immature sperm increased up to 83.40 ± 0.89%. In conclusion, ATR not only induced its detrimental effect on the endocrine function of the testes and pituitary gland but also affected the cytoplasmic CH ratio and consequently leads to inadequate energy supplement in spermatogenesis cells. Therefore the imbalanced oxidative stress occurs in testicular tissue, which in turn enhances the sperm DNA disintegrity and nuclear immaturity.

  14. 上海市居民膳食中铅镉暴露水平评估%Assessment on the dietary exposure of lead and cadmium in Shanghai residents

    刘弘; 吴春峰; 陆屹; 方亚敏; 高围溦; 邢之慧; 陆冬磊

    2011-01-01

    Objective To obtain the basic data of lead and cadmium exposure from food for Shanghai residents, and to estimate the health risk of dietary lead and cadmium contamination in Shanghai. Methods A method recommended by WHO on the dietary exposure assessment of chemicals in food was applied. Surveillance on the content of lead and cadmium in food combined with a survey on dietary nutrients intake of Shanghai residents was conducted. Results The average dietary lead and cadmium exposure of Shanghai residents per week were estimated to be 0.006 2 mg/kg BW and 0.002 5 mg/kg BW, accounted for 24.77% and 35.06% of provisional tolerable weekly intake ( PTWI), respectively.The dietary lead and cadmium exposure per week of top consumers ( the food consumption was higher than the upper 90th percentile) were estimated to be 0.012 3 and 0.004 8 mg/kg Bw, accounted for 49.08% and 68.09% of PTWI.Conclusion The level of dietary cadmium exposure in Shanghai residents was higher than that of dietary lead exposure.Although both dietary lead and cadmium exposure level in Shanghai residents is usually lower than PTWI, cutting it down is necessary.%目的 了解上海市居民膳食中铅、镉暴露的基础数据,评估上海市市售食品中铅、镉污染的危险性.方法 对上海市市售食品中铅、镉含量进行监测,并结合上海市居民膳食营养素摄入量调查,应用WHO推荐的食品中化学污染物膳食暴露评估方法,对上海市居民膳食中铅、镉暴露水平进行评估.结果 上海市居民平均每周膳食中铅、镉暴露量分别为0.006 2、0.002 5 mg/kg BW,占暂定每周可耐受摄入量(PTWI)的24.77%、35.06%.高端消费人群(食物消费量第90百分位数)每周膳食中铅、镉暴露量分别为0.012 3和0.0048 mg/kg BW,占PTWI的49.08%、68.09%.结论 上海市居民膳食中镉暴露水平高于铅暴露水平,正常情况下均低于PTWI,但仍有进一步降低的必要.

  15. Transient cell function disruption by low dose acute exposure of ionizing radiation

    Incubation of BMG-1 cells with thallium chloride (201Tl) in the range of diagnostic dose did not show a smooth uptake curve and appeared to have an unsuspected deviation in initial phase. In the present study this unexpected phenomenon was explored, using commonly used radionuclides (viz., 201Tl and 131I). Comparison was made with technetium-99m pertechnetate (99mTcO4) and technetium-99m labeled methoxyisobutylisonitrile (99mTc-MIBI) that are known to show conventional 2 phase graph representing inflow and outflow segments. Serial in vitro, ex-vivo and in vivo gamma scintigraphy as well as NMR spectroscopy experiments were conducted to corroborate the results. BMG-1 cells demonstrated a four-phase uptake pattern with 201Tl as compared to a conventional biphasic pattern with 99mTc-MIBI. Flow cytometry data however did not reveal any 201Tl induced cell injury. Further, mice tissue extracts injected with 201Tl also showed a transient depression in its uptake. Scintigraphy experiments in rabbits administered with diagnostic dose of 201Tl and 131I confirmed the in vitro and ex vivo findings. Further, proton NMR spectroscopy showed decrease in the level of choline at 3 h and 24 h in 201Tl treated animals as compared to control. Phosphoethanolamine peak firstly decreased at 3 h but reached normal level at 24 h time point. No significant change was observed in the level of betaine. This transient reduction in internalization of 201Tl and 131I may represent a hitherto unknown acute effect of low dose radiation, i.e., transient depression in Na+-K+ ATPase pump activity without any apparent evidence of cell damage, representing a transient cell membrane dysfunction. The phenomenon may present a mechanistical explanation of 'thyroid stunning' at cellular level and suggest that it may be more universal in nature than suspected till now. (author)

  16. Acute exposure of mice to high-dose ultrafine carbon black decreases susceptibility to pneumococcal pneumonia

    Gordon Stephen

    2010-10-01

    Full Text Available Abstract Background Epidemiological studies suggest that inhalation of carbonaceous particulate matter from biomass combustion increases susceptibility to bacterial pneumonia. In vitro studies report that phagocytosis of carbon black by alveolar macrophages (AM impairs killing of Streptococcus pneumoniae. We have previously reported high levels of black carbon in AM from biomass smoke-exposed children and adults. We therefore aimed to use a mouse model to test the hypothesis that high levels of carbon loading of AM in vivo increases susceptibility to pneumococcal pneumonia. Methods Female outbred mice were treated with either intranasal phosphate buffered saline (PBS or ultrafine carbon black (UF-CB in PBS; 500 μg on day 1 and day 4, and then infected with S. pneumoniae strain D39 on day 5. Survival was assessed over 72 h. The effect of UF-CB on AM carbon loading, airway inflammation, and a urinary marker of pulmonary oxidative stress was assessed in uninfected animals. Results Instillation of UF-CB in mice resulted a pattern of AM carbon loading similar to that of biomass-smoke exposed humans. In uninfected animals, UF-CB treated animals had increased urinary 8-oxodG (P = 0.055, and an increased airway neutrophil differential count (P . pneumoniae, whereas morbidity and mortality after infection was reduced in UF-CB treated animals (median survival 48 h vs. 30 h, P . pneumoniae colony forming unit counts, and lower airway levels of keratinocyte-derived chemokine/growth-related oncogene (KC/GRO, and interferon gamma. Conclusion Acute high level loading of AM with ultrafine carbon black particles per se does not increase the susceptibility of mice to pneumococcal infection in vivo.

  17. Follow-up of delayed health consequences of acute radiation exposure. Lessons to be learned from their medical management

    While the use of radioactive materials around the world offers a wide range of benefits in medicine, industry and research, safety precautions are essential to limit the exposure of persons to harmful radiation. When the quantity of radioactive material employed is substantial, as when radioactive sources are used for radiotherapy in medicine or for industrial radiography, extreme care is necessary to prevent accidents that may lead to severe health consequences for the individuals involved. Despite the fact that the precautions to be taken are clearly established, accidents with radiation sources continue to occur, albeit infrequently. The IAEA, as part of its 'Safety of Radiation Sources' and 'Emergency Response' subprogrammes, follows up severe accidents of this kind. In so doing, the IAEA attempts to document both the circumstances leading to the accident and the subsequent medical treatment in order to define the lessons to be learned from these events. The overall objective is to provide information that will be of benefit to organizations with responsibilities for radiation protection, the safety of radiation sources and the medical management of radiation accidents. The International Atomic Energy Agency has issued a number of publications on radiation accidents which have occurred in the past 15 years, reporting on the causes, radiation safety aspects and medical management of those affected particularly in the acute phase following an accident. These reports cover the accidents in Chernobyl, Ukraine (the Republic of the former Soviet Union) and Goiania (Brazil), and those in El Salvador, Vietnam, Belarus, Israel, Estonia, Costa Rica, Georgia, Russian Federation, Turkey, Peru and Panama. In 1998 the IAEA published three Safety Reports, co-sponsored by the World Health Organization, aimed at disseminating medical information on the recognition and treatment of radiation injuries, planning the medical response to radiation accidents and occupational health

  18. Induction of characteristic hepatocyte proliferative lesion with dietary exposure of Wistar Hannover rats to tocotrienol for 1 year

    Tocotrienol is an antioxidant which has found commercial application as a food additive and health supplement all over the world. Since there have been no reports regarding toxicological effects of long-term exposure, we performed a 52-week chronic study using Wistar Hannover rats of both sexes given the compound at doses of 0, 0.08, 0.4 or 2% in powdered basal diet. Since 6 animals in the 2% male group died of hemorrhage of several organs by week 50, the maximum dose level was changed to 1% in both sexes for the last 2 weeks. Decrease of body weight gain was observed in the 2% males from week 5 and females from week 10, this persisting to the end of the study. With the high dose, prolongation of prothrombin time and increase of serum ALT in males, and increase of serum ALP in both sexes were observed with statistical significance. In male and female rats receiving 0.4% or less, there were no toxicological changes in any of the parameters examined. At necropsy, multiple cyst-like nodules on the liver surface were macroscopically pronounced in both sexes receiving 2%. On histopathological examination, hepatocellular nodules were evident with distortion of hepatic cords and compression of the surrounding tissue, almost all including areas of spongiosis hepatis. The constituent hepatocytes were immunohistochemically stained with proliferation cell nuclear antigen at high rates. Nevertheless, they did not exhibit overt atypia and the basic lobular architecture remained intact. Additionally, they were consistently negative for glutathione S-transferase placental form (GST-P). Accordingly, we propose the newly categorized but previously used name 'nodular hepatocellular hyperplasia', which may not necessarily have a neoplastic or regenerative nature. However, quantitative GST-P analysis of the liver sections overall showed numbers of GST-P foci in the high dose females to be significantly elevated as compared to the control value. Based on the present data demonstrating

  19. An integrated functional genomic study of acute phenobarbital exposure in the rat

    Dow Jacky

    2010-01-01

    Full Text Available Abstract Background Non-genotoxic carcinogens are notoriously difficult to identify as they do not damage DNA directly and have diverse modes of action, necessitating long term in vivo studies. The early effects of the classic rodent non-genotoxic hepatocarcinogen phenobarbital have been investigated in the Fisher rat using a combination of metabolomics and transcriptomics, to investige early stage mechanistic changes that are predictive of longer term pathology. Results Liver and blood plasma were profiled across 14 days, and multivariate statistics used to identify perturbed pathways. Both metabolomics and transcriptomics detected changes in the liver which were dose dependent, even after one day of exposure. Integration of the two datasets associated perturbations with specific pathways. Hepatic glycogen was decreased due to a decrease in synthesis, and plasma triglycerides were decreased due to an increase in fatty acid uptake by the liver. Hepatic succinate was increased and this was associated with increased heme biosynthesis. Glutathione synthesis was also increased, presumably in response to oxidative stress. Liquid Chromatography Mass Spectrometry demonstrated a remodeling of lipid species, possibly resulting from proliferation of the smooth endoplasmic reticulum. Conclusions The data fusion of metabolomic and transcriptomic changes proved to be a highly sensitive approach for monitoring early stage changes in altered hepatic metabolism, oxidative stress and cytochrome P450 induction simultaneously. This approach is particularly useful in interpreting changes in metabolites such as succinate which are hubs of metabolism.

  20. Sampling strategies for estimating acute and chronic exposures of pesticides in streams

    Crawford, Charles G.

    2004-01-01

    The Food Quality Protection Act of 1996 requires that human exposure to pesticides through drinking water be considered when establishing pesticide tolerances in food. Several systematic and seasonally weighted systematic sampling strategies for estimating pesticide concentrations in surface water were evaluated through Monte Carlo simulation, using intensive datasets from four sites in northwestern Ohio. The number of samples for the strategies ranged from 4 to 120 per year. Sampling strategies with a minimal sampling frequency outside the growing season can be used for estimating time weighted mean and percentile concentrations of pesticides with little loss of accuracy and precision, compared to strategies with the same sampling frequency year round. Less frequent sampling strategies can be used at large sites. A sampling frequency of 10 times monthly during the pesticide runoff period at a 90 km 2 basin and four times monthly at a 16,400 km2 basin provided estimates of the time weighted mean, 90th, 95th, and 99th percentile concentrations that fell within 50 percent of the true value virtually all of the time. By taking into account basin size and the periodic nature of pesticide runoff, costs of obtaining estimates of time weighted mean and percentile pesticide concentrations can be minimized.

  1. An Exploratory Study on the Development of an Animal Model of Acute Pancreatitis Following Nicotine Exposure

    Chowdhury P

    2003-09-01

    Full Text Available Abstract Cigarette smoking is known to be a major risk factor for pancreatic cancer and pancreatitis is believed to be a predisposed condition for pancreatic cancer. As of this date, there is no established experimental animal model to conduct detailed studies on these two deadly diseases. Our aim is to establish a rodent model by which we can systematically study the pathogenesis of pancreatitis and pancreatic cancer. Methods Adult Male Sprague Dawley rats were exposed to graded doses of nicotine by various routes for periods of three to 16 weeks. Blood samples were measured for hormonal and metabolic parameters. The pancreas was evaluated for histopathological changes and its function was assessed in isolated pancreatic acini upon stimulation with cholecystokinin (CCK or carbachol (Cch. The pancreatic tissue was evaluated further for oncogene expression. Results Body weight, food and fluid intakes, plasma glucose and insulin levels were significantly reduced in animals with nicotine exposure when compared to control. However, CCK and gastrin levels in the blood were significantly elevated. Pancreatic function was decreased significantly with no alteration in CCK receptor binding. Pancreatic histology revealed vacuolation, swelling, cellular pyknosis and karyorrhexis. Mutant oncogene, H-ras, was overexpressed in nicotine-treated pancreatic tissue. Summary and conclusion The results suggest that alterations in metabolic, hormonal and pathologic parameters following nicotine-treatment appear consistent with diagnostic criteria of human pancreatitis. It is proposed that rats could be considered as a potential animal model to study the pathogenesis of pancreatitis.

  2. Confirmation of childhood acute lymphoblastic leukemia variants, ARID5B and IKZF1, and interaction with parental environmental exposures.

    Tiffany-Jane Evans

    Full Text Available Genome wide association studies (GWAS have established association of ARID5B and IKZF1 variants with childhood acute lymphoblastic leukemia (ALL. Epidemiological studies suggest that environmental factors alone appear to make a relatively minor contribution to disease risk. The polygenic nature of childhood ALL predisposition together with the timing of environmental triggers may hold vital clues for disease etiology. This study presents results from an Australian GWAS of childhood ALL cases (n = 358 and population controls (n = 1192. Furthermore, we utilised family trio (n = 204 genotypes to extend our investigation to gene-environment interaction of significant loci with parental exposures before conception, and child's sex and age. Thirteen SNPs achieved genome wide significance in the population based case/control analysis; ten annotated to ARID5B and three to IKZF1. The most significant SNPs in these regions were ARID5B rs4245595 (OR 1.63, CI 1.38-1.93, P = 2.13×10(-9, and IKZF1 rs1110701 (OR 1.69, CI 1.42-2.02, p = 7.26×10(-9. There was evidence of gene-environment interaction for risk genotype at IKZF1, whereby an apparently stronger genetic effect was observed if the mother took folic acid or if the father did not smoke prior to pregnancy (respective interaction P-values: 0.04, 0.05. There were no interactions of risk genotypes with age or sex (P-values >0.2. Our results evidence that interaction of genetic variants and environmental exposures may further alter risk of childhood ALL however, investigation in a larger population is required. If interaction of folic acid supplementation and IKZF1 variants holds, it may be useful to quantify folate levels prior to initiating use of folic acid supplements.

  3. Infantile 4-tert-octylphenol exposure transiently inhibits rat ovarian steroidogenesis and steroidogenic acute regulatory protein (StAR) expression

    Phenolic compounds, such as 4-tert-octylphenol (OP), have been shown to interfere with rat ovarian steroidogenesis. However, little is known about steroidogenic effects of infantile OP exposure on immature ovary. The aim of the present study was to investigate the effects of infantile OP exposure on plasma FSH, LH, estradiol, and progesterone levels in 14-day-old female rats. The effect on ovarian steroidogenic acute regulatory protein (StAR) and FSH receptor (FSHr) expression was analyzed by Western blotting. Ex vivo analysis was carried out for follicular estradiol, progesterone, testosterone, and cAMP production. Sprague-Dawley rats were given OP (0, 10, 50, or 100 mg/kg) subcutaneously on postnatal days 6, 8, 10, and 12. On postnatal day 14, plasma FSH was decreased and progesterone increased significantly at a dose of 100 mg OP/kg. In addition, the highest OP dose advanced the time of vaginal opening in puberty. OP had no effect on infantile LH and estradiol levels or ovarian FSHr content. Ovarian StAR protein content and ex vivo hormone and cAMP production were decreased at all OP doses compared to controls. However, hormone levels recovered independent on FSH and even increased above the control level during a prolonged culture. On postnatal day 35, no statistically significant differences were seen between control and OP-exposed animals in plasma FSH, LH, estradiol, and progesterone levels, or in ovarian StAR protein content. The results indicate that the effect of OP on the infantile ovary is reversible, while more permanent effects in the hypothalamus and pituitary, as described earlier, are involved in the reduction of circulating FSH levels and premature vaginal opening

  4. Point-of-care procalcitonin test to reduce antibiotic exposure in patients hospitalized with acute exacerbation of COPD

    Corti, Caspar; Fally, Markus; Fabricius-Bjerre, Andreas; Mortensen, Katrine; Jensen, Birgitte Nybo; Andreassen, Helle F; Porsbjerg, Celeste; Knudsen, Jenny Dahl; Jensen, Jens-Ulrik

    2016-01-01

    Background This study was conducted to investigate whether point-of-care (POC) procalcitonin (PCT) measurement can reduce redundant antibiotic treatment in patients hospitalized with acute exacerbation of COPD (AECOPD). Methods One-hundred and twenty adult patients admitted with AECOPD were enrolled in this open-label randomized trial. Patients were allocated to either the POC PCT-guided intervention arm (n=62) or the control arm, in which antibiotic therapy followed local guidelines (n=58). Results The median duration of antibiotic exposure was 3.5 (interquartile range [IQR] 0–10) days in the PCT-arm vs 8.5 (IQR 1–11) days in the control arm (P=0.0169, Wilcoxon) for the intention-to-treat population. The proportion of patients using antibiotics for ≥5 days within the 28-day follow-up was 41.9% (PCT-arm) vs 67.2% (P=0.006, Fisher’s exact) in the intention-to-treat population. For the per-protocol population, the proportions were 21.1% (PCT-arm) vs 73.9% (P<0.00001, Fisher’s exact). Within 28-day follow-up, one patient died in the PCT-arm and two died in the control arm. A composite harm end point consisting of death, rehospitalization, or intensive care unit admission, all within 28 days, showed no apparent difference. Conclusion Our study shows that the implementation of a POC PCT-guided algorithm can be used to substantially reduce antibiotic exposure in patients hospitalized with AECOPD, with no apparent harm. PMID:27382274

  5. Acute effects of tetracycline exposure in the freshwater fish Gambusia holbrooki: antioxidant effects, neurotoxicity and histological alterations.

    Nunes, B; Antunes, S C; Gomes, R; Campos, J C; Braga, M R; Ramos, A S; Correia, A T

    2015-02-01

    A large body of evidence was compiled in the recent decades showing a noteworthy increase in the detection of pharmaceutical drugs in aquatic ecosystems. Due to its ubiquitous presence, chemical nature, and practical purpose, this type of contaminant can exert toxic effects in nontarget organisms. Exposure to pharmaceutical drugs can result in adaptive alterations, such as changes in tissues, or in key homeostatic mechanisms, such as antioxidant mechanisms, biochemical/physiological pathways, and cellular damage. These alterations can be monitored to determine the impact of these compounds on exposed aquatic organisms. Among pharmaceutical drugs in the environment, antibiotics are particularly important because they include a variety of substances widely used in medical and veterinary practice, livestock production, and aquaculture. This wide use constitutes a decisive factor contributing for their frequent detection in the aquatic environment. Tetracyclines are the individual antibiotic subclass with the second highest frequency of detection in environmental matrices. The characterization of the potential ecotoxicological effects of tetracycline is a much-required task; to attain this objective, the present study assessed the acute toxic effects of tetracycline in the freshwater fish species Gambusia holbrooki by the determination of histological changes in the gills and liver, changes in antioxidant defense [glutathione S-transferase (GST), catalase (CAT), and lipoperoxidative damage] as well as potential neurotoxicity (acetylcholinesterase activity). The obtained results suggest the existence of a cause-and-effect relationship between the exposure to tetracycline and histological alterations (more specifically in gills) and enzymatic activity (particularly the enzyme CAT in liver and GST in gills) indicating that this compound can exert a pro-oxidative activity. PMID:25475590

  6. CHRONIC DIETARY EXPOSURE WITH INTERMITTENT SPIKE DOSES OF CHLORPYRIFOS FALLS TO ALTER SOMATOSENSORY EVOKED POTENTIALS, COMPOUND NERVE ACTION POTENTIALS, OR NERVE CONDUCTION VELOCITY IN RATS.

    Human exposure to pesticides is often characterized by chronic low level exposure with intermittent spiked higher exposures. Cholinergic transmission is involved in sensory modulation in the cortex and cerebellum, and therefore may be altered following chlorpyrifos (CPF) exposure...

  7. Metallothionein blocks oxidative DNA damage induced by acute inorganic arsenic exposure

    We studied how protein metallothionein (MT) impacts arsenic-induced oxidative DNA damage (ODD) using cells that poorly express MT (MT-I/II double knockout embryonic cells; called MT-null cells) and wild-type (WT) MT competent cells. Arsenic (as NaAsO2) was less cytolethal over 24 h in WT cells (LC50 = 11.0 ± 1.3 μM; mean ± SEM) than in MT-null cells (LC50 = 5.6 ± 1.2 μM). ODD was measured by the immuno-spin trapping method. Arsenic (1 or 5 μM; 24 h) induced much less ODD in WT cells (121% and 141% of control, respectively) than in MT-null cells (202% and 260%). In WT cells arsenic caused concentration-dependent increases in MT expression (transcript and protein), and in the metal-responsive transcription factor-1 (MTF-1), which is required to induce the MT gene. In contrast, basal MT levels were not detectable in MT-null cells and unaltered by arsenic exposure. Transfection of MT-I gene into the MT-null cells markedly reduced arsenic-induced ODD levels. The transport genes, Abcc1 and Abcc2 were increased by arsenic in WT cells but either showed no or very limited increases in MT-null cells. Arsenic caused increases in oxidant stress defense genes HO-1 and GSTα2 in both WT and MT-null cells, but to much higher levels in WT cells. WT cells appear more adept at activating metal transport systems and oxidant response genes, although the role of MT in these responses is unclear. Overall, MT protects against arsenic-induced ODD in MT competent cells by potential sequestration of scavenging oxidant radicals and/or arsenic. - Highlights: • Metallothionein blocks arsenic toxicity. • Metallothionein reduces arsenic-induced DNA damage. • Metallothionein may bind arsenic or radicals produced by arsenic

  8. Characterization of seizures induced by acute exposure to an organophosphate herbicide, glufosinate-ammonium.

    Calas, André-Guilhem; Perche, Olivier; Richard, Olivier; Perche, Astrid; Pâris, Arnaud; Lauga, Fabien; Herzine, Ameziane; Palomo, Jennifer; Ardourel, Marie-Yvonne; Menuet, Arnaud; Mortaud, Stéphane; Pichon, Jacques; Montécot-Dubourg, Céline

    2016-05-01

    Glufosinate-ammonium (GLA), the active component of a widely used herbicide, induces convulsions in rodents and humans. In mouse, intraperitoneal treatment with 75 mg/kg GLA generates repetitive tonic-clonic seizures associated with 100% mortality within 72 h after treatment. In this context, we characterized GLA-induced seizures, their histological consequences and the effectiveness of diazepam treatment. Epileptic discharges on electroencephalographic recordings appeared simultaneously in the hippocampus and the cerebral cortex. Diazepam treatment at 6 h immediately stopped the seizures and prevented animal death. However, intermittent seizures were recorded on electroencephalogram from 6 h after diazepam treatment until 24 h, but had disappeared after 15 days. In our model, neuronal activation (c-Fos immunohistochemistry) was observed 6 h after GLA exposure in the dentate gyrus, CA1, CA3, amygdala, piriform and entorhinal cortices, indicating the activation of the limbic system. In these structures, Fluoro-Jade C and Cresyl violet staining did not show neuronal suffering. However, astroglial activation was clearly observed at 24 h and 15 days after GLA treatment in the amygdala, piriform and entorhinal cortices by PCR quantitative, western blot and immunohistochemistry. Concomitantly, glutamine synthetase mRNA expression (PCR quantitative), protein expression (western blot) and enzymatic activity were upregulated. In conclusion, our study suggests that GLA-induced seizures: (a) involved limbic structures and (b) induced astrocytosis without neuronal degeneration as an evidence of a reactive astrocyte beneficial effect for neuronal protection. PMID:27031874

  9. Acute pulmonary inflammation induced by exposure of the airways to staphylococcal enterotoxin type B in rats

    Staphylocococcus aureus is a gram-positive bacterium that produces several enterotoxins, which are responsible for most part of pathological conditions associated to staphylococcal infections, including lung inflammation. This study aimed to investigate the underlying inflammatory mechanisms involved in leukocyte recruitment in rats exposed to staphylococcal enterotoxin B (SEB). Rats were anesthetized with pentobarbital sodium and intratracheally injected with either SEB or sterile phosphate-buffered saline (PBS, 0.4 ml). Airways exposition to SEB (7.5-250 ng/trachea) caused a dose- and time-dependent neutrophil accumulation in BAL fluid, the maximal effects of which were observed at 4 h post-SEB exposure (250 ng/trachea). Eosinophils were virtually absent in BAL fluid, whereas mononuclear cell counts increased only at 24 h post-SEB. Significant elevations of granulocytes in bone marrow (mature and immature forms) and peripheral blood have also been detected. In BAL fluid, marked elevations in the levels of lipid mediators (LTB4 and PGE2) and cytokines (TNF-α, IL-6 and IL-10) were observed after SEB instillation. The SEB-induced neutrophil accumulation in BAL fluid was reduced by pretreatment with dexamethasone (0.5 mg/kg), the COX-2 inhibitor celecoxib (3 mg/kg), the selective iNOS inhibitor compound 1400 W (5 mg/kg) and the lipoxygenase inhibitor AA-861 (200 μg/kg). In separate experiments carried out with rat isolated peripheral neutrophils, SEB failed to induce neutrophil adhesion to serum-coated plates and chemotaxis. In conclusion, rat airways exposition to SEB causes a neutrophil-dependent lung inflammation at 4 h as result of the release of proinflammatory (NO, PGE2, LTB4, TNF-α, IL-6) and anti-inflammatory mediators (IL-10)

  10. Urinary Metabolites of the Dietary Carcinogen PhIP are Predictive of Colon DNA Adducts After a Low Dose Exposure in Humans

    Epidemiologic evidence indicates that exposure to heterocyclic amines (HAs) in the diet is an important risk factor for the development of colon cancer. Well-done cooked meats contain significant levels of HAs which have been shown to cause cancer in laboratory animals. To better understand the mechanisms of HA bioactivation in humans, the most mass abundant HA, 2-amino-l-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), was used to assess the relationship between PhIP metabolism and DNA adduct formation. Ten human volunteers were administered a dietary relevant dose of [14C]PhIP 48-72 h prior to surgery to remove colon tumors. Urine was collected for 24 h after dosing for metabolite analysis, and DNA was extracted from colon tissue and analyzed by accelerator mass spectrometry for DNA adducts. All ten subjects were phenotyped for CYP1A2, NAT2, and SULT1A1 enzyme activity. Twelve PhIP metabolites were detected in the urine samples. The most abundant metabolite in all volunteers was N-hydroxy-PhIP-N2-glucuronide. Metabolite levels varied significantly between the volunteers. Interindividual differences in colon DNA adducts levels were observed between each individual. The data showed that individuals with a rapid CYP1A2 phenotype and high levels of urinary N-hydroxy-PhIP-N2-glucuronide, had the lowest level of colon PhIP-DNA adducts. This suggests that glucuronidation plays a significant role in detoxifying N-hydroxy-PhIP. The levels of urinary N-hydroxy-PhIP-N2-glucuronide were negatively correlated to colon DNA adduct levels. Although it is difficult to make definite conclusions from a small data set, the results from this pilot study have encouraged further investigations using a much larger study group

  11. Urinary Metabolites of the Dietary Carcinogen PhIP are Predictive of Colon DNA Adducts After a Low Dose Exposure in Humans

    Malfatti, M; Dingley, K; Nowell, S; Ubick, E; Mulakken, N; Nelson, D; Lang, N; Felton, J; Turteltaub, K

    2006-04-28

    Epidemiologic evidence indicates that exposure to heterocyclic amines (HAs) in the diet is an important risk factor for the development of colon cancer. Well-done cooked meats contain significant levels of HAs which have been shown to cause cancer in laboratory animals. To better understand the mechanisms of HA bioactivation in humans, the most mass abundant HA, 2-amino-l-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), was used to assess the relationship between PhIP metabolism and DNA adduct formation. Ten human volunteers were administered a dietary relevant dose of [{sup 14}C]PhIP 48-72 h prior to surgery to remove colon tumors. Urine was collected for 24 h after dosing for metabolite analysis, and DNA was extracted from colon tissue and analyzed by accelerator mass spectrometry for DNA adducts. All ten subjects were phenotyped for CYP1A2, NAT2, and SULT1A1 enzyme activity. Twelve PhIP metabolites were detected in the urine samples. The most abundant metabolite in all volunteers was N-hydroxy-PhIP-N{sup 2}-glucuronide. Metabolite levels varied significantly between the volunteers. Interindividual differences in colon DNA adducts levels were observed between each individual. The data showed that individuals with a rapid CYP1A2 phenotype and high levels of urinary N-hydroxy-PhIP-N{sup 2}-glucuronide, had the lowest level of colon PhIP-DNA adducts. This suggests that glucuronidation plays a significant role in detoxifying N-hydroxy-PhIP. The levels of urinary N-hydroxy-PhIP-N{sup 2}-glucuronide were negatively correlated to colon DNA adduct levels. Although it is difficult to make definite conclusions from a small data set, the results from this pilot study have encouraged further investigations using a much larger study group.

  12. Implications for wildlife and humans of dietary exposure to lead from fragments of lead rifle bullets in deer shot in the UK

    Lead poisoning caused by ingested spent lead shotgun pellets has long been known to be a cause of unnecessary mortality in waterfowl and has led to legislation limiting its use in many countries. Recent evidence has shown that the problem extends to terrestrial ecosystems and to fragmented rifle bullets eaten by scavengers as well as shotgun pellets. Dietary exposure of human consumers to lead from spent ammunition in game meat also poses potential risks to human health. To assess the degree of fragmentation of lead bullets used to kill wild deer, twelve deer were shot in the thorax using copper-jacketed lead-cored bullets, as part of planned deer management operations. The thoracic region of the eviscerated carcasses and the abdominal viscera of each deer were X-rayed. An average of 356 metal fragments was visible on radiographs of the carcass and 180 fragments in the viscera. The weight of fragments was estimated by reference to an X-rayed scale of fragments of known weight. The average total weight of metal fragments, likely to be mostly lead, was estimated to be 1.2 g for the carcass and 0.2 g for the viscera. The total estimated weight of fragments in the entire carcass was estimated to be 17% of the weight of the bullet. Most fragments were small in size, with those in the viscera being smaller than those in the carcass. Metal fragments in the viscera were sufficiently small that at least 80% of the metallic bullet-derived lead in the viscera would be expected to be ingested by scavenging birds, such as buzzards and eagles, which feed on them.

  13. Metallothionein blocks oxidative DNA damage induced by acute inorganic arsenic exposure

    Qu, Wei, E-mail: qu@niehs.nih.gov; Waalkes, Michael P.

    2015-02-01

    We studied how protein metallothionein (MT) impacts arsenic-induced oxidative DNA damage (ODD) using cells that poorly express MT (MT-I/II double knockout embryonic cells; called MT-null cells) and wild-type (WT) MT competent cells. Arsenic (as NaAsO{sub 2}) was less cytolethal over 24 h in WT cells (LC{sub 50} = 11.0 ± 1.3 μM; mean ± SEM) than in MT-null cells (LC{sub 50} = 5.6 ± 1.2 μM). ODD was measured by the immuno-spin trapping method. Arsenic (1 or 5 μM; 24 h) induced much less ODD in WT cells (121% and 141% of control, respectively) than in MT-null cells (202% and 260%). In WT cells arsenic caused concentration-dependent increases in MT expression (transcript and protein), and in the metal-responsive transcription factor-1 (MTF-1), which is required to induce the MT gene. In contrast, basal MT levels were not detectable in MT-null cells and unaltered by arsenic exposure. Transfection of MT-I gene into the MT-null cells markedly reduced arsenic-induced ODD levels. The transport genes, Abcc1 and Abcc2 were increased by arsenic in WT cells but either showed no or very limited increases in MT-null cells. Arsenic caused increases in oxidant stress defense genes HO-1 and GSTα2 in both WT and MT-null cells, but to much higher levels in WT cells. WT cells appear more adept at activating metal transport systems and oxidant response genes, although the role of MT in these responses is unclear. Overall, MT protects against arsenic-induced ODD in MT competent cells by potential sequestration of scavenging oxidant radicals and/or arsenic. - Highlights: • Metallothionein blocks arsenic toxicity. • Metallothionein reduces arsenic-induced DNA damage. • Metallothionein may bind arsenic or radicals produced by arsenic.

  14. Effects of Exposure to Carbon Dioxide and Bioeffluents on Perceived Air Quality, Self-assessed Acute Health Symptoms and Cognitive Performance

    Zhang, Xiaojing; Wargocki, Pawel; Lian, Zhiwei;

    2016-01-01

    quality, increased the intensity of reported headache, fatigue, sleepiness and difficulty in thinking clearly, and reduced speed of addition, the response time in a redirection task and the number of correct links made in the cue-utilisation test. This suggests that moderate concentrations of bioeffluents...... ratings, physiological responses and cognitive performance were measured. No statistically significant effects on perceived air quality, acute health symptoms or cognitive performance were seen during exposures when CO2 was added. Exposures to bioeffluents with CO2 at 3,000 ppm reduced perceived air...

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

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

    2010-01-01

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

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

    Madden, Jill A. [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Hoyer, Patricia B. [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Devine, Patrick J. [INRS—Institut Armand-Frappier Research Centre, University of Quebec, Laval, QC H7V 1B7 (Canada); Keating, Aileen F., E-mail: akeating@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States)

    2014-05-01

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

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

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKTThr308 protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  18. Risk factors for high-altitude headache upon acute high-altitude exposure at 3700 m in young Chinese men: a cohort study

    Bian, Shi-Zhu; Zhang, Ji-Hang; Xu-bin GAO; Li, Ming; Yu, Jie; Liu, Xi; Dong, Jun-Qing; Chen, Guo-Zhu; Huang, Lan

    2013-01-01

    Background This prospective and observational study aimed to identify demographic, physiological and psychological risk factors associated with high-altitude headache (HAH) upon acute high-altitude exposure. Methods Eight hundred fifty subjects ascended by plane to 3700 m above Chengdu (500 m) over a period of two hours. Structured Case Report Form (CRF) questionnaires were used to record demographic information, physiological examinations, psychological scale, and symptoms including headache...

  19. Hemodynamic characteristics of high-altitude headache following acute high altitude exposure at 3700 m in young Chinese men

    Bian, Shi-Zhu; JIN, JUN; Li, Qian-Ning; Yu, Jie; Tang, Cai-Fa; Rao, Rong-Sheng; Yu, Shi-Yong; Zhao, Xiao-Hui; Qin, Jun; Huang, Lan

    2015-01-01

    Background This study aimed to identify the systemic and cerebral hemodynamic characteristics and their roles in high-altitude headache (HAH) among young Chinese men following acute exposure. Methods The subjects (n = 385) were recruited in June and July of 2012. They completed case report form questionnaires, as well as heart rate (HR), blood pressure, echocardiogram and transcranial Doppler examinations at 3700 m following a two-hour plane flight. A subgroup of 129 participants was examined...

  20. Analysis of the effects of exposure to acute hypoxia on oxidative lesions and tumour progression in a transgenic mouse breast cancer model

    Tumour hypoxia is known to be a poor prognostic indicator, predictive of increased risk of metastatic disease and reduced survival. Genomic instability has been proposed as one of the potential mechanisms for hypoxic tumour progression. Both of these features are commonly found in many cancer types, but their relationship and association with tumour progression has not been examined in the same model. To address this issue, we determined the effects of 6 week in vivo acute hypoxic exposure on the levels of mutagenic lipid peroxidation product, malondialdehyde, and 8-oxo-7,8-dihydro-2'-deoxyguanosine DNA (8-oxo-dG) lesions in the transgenic polyomavirus middle T (PyMT) breast cancer mouse model. We observed significantly increased plasma lipid peroxidation and 8-oxo-dG lesion levels in the hypoxia-exposed mice. Consumption of malondialdehyde also induced a significant increase in the PyMT tumour DNA lesion levels, however, these increases did not translate into enhanced tumour progression. We further showed that the in vivo exposure to acute hypoxia induced accumulation of F4/80 positive tumour-associated macrophages (TAMs), demonstrating a relationship between hypoxia and macrophages in an experimental model. These data suggest that although exposure to acute hypoxia causes an increase in 8-oxo-dG lesions and TAMs in the PyMT tumours, these increases do not translate into significant changes in tumour progression at the primary or metastatic levels in this strong viral oncogene-driven breast cancer model

  1. Reactive oxygen species produced by NADPH oxidase and mitochondrial dysfunction in lung after an acute exposure to Residual Oil Fly Ashes

    Reactive O2 species production triggered by particulate matter (PM) exposure is able to initiate oxidative damage mechanisms, which are postulated as responsible for increased morbidity along with the aggravation of respiratory diseases. The aim of this work was to quantitatively analyse the major sources of reactive O2 species involved in lung O2 metabolism after an acute exposure to Residual Oil Fly Ashes (ROFAs). Mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight), and lung samples were analysed 1 h after instillation. Tissue O2 consumption and NADPH oxidase (Nox) activity were evaluated in tissue homogenates. Mitochondrial respiration, respiratory chain complexes activity, H2O2 and ATP production rates, mitochondrial membrane potential and oxidative damage markers were assessed in isolated mitochondria. ROFA exposure was found to be associated with 61% increased tissue O2 consumption, a 30% increase in Nox activity, a 33% increased state 3 mitochondrial O2 consumption and a mitochondrial complex II activity increased by 25%. During mitochondrial active respiration, mitochondrial depolarization and a 53% decreased ATP production rate were observed. Neither changes in H2O2 production rate, nor oxidative damage in isolated mitochondria were observed after the instillation. After an acute ROFA exposure, increased tissue O2 consumption may account for an augmented Nox activity, causing an increased O2·− production. The mitochondrial function modifications found may prevent oxidative damage within the organelle. These findings provide new insights to the understanding of the mechanisms involving reactive O2 species production in the lung triggered by ROFA exposure. - Highlights: • Exposure to ROFA alters the oxidative metabolism in mice lung. • The augmented Nox activity contributes to the high tissue O2 consumption. • Exposure to ROFA produces alterations in mitochondrial function. • ΔΨm decrease in state 3 may be responsible

  2. Effects of acute psychosocial stress exposure on endocrine and affective reactivity in college students differing in the 5-HTTLPR genotype and trait neuroticism.

    Verschoor, Ellen; Markus, C Rob

    2011-07-01

    Enhanced stress vulnerability has been implicated in the pathogenesis of affective disorders. Although both genetic (5-HTTLPR) and cognitive (neuroticism) factors are known to increase stress vulnerability, no experimental study has investigated the interaction between these two factors on psychobiological reactivity following acute stress exposure. This study used a balanced experimental design to examine the interaction between the 5-HTTLPR genotype and trait neuroticism in neuroendocrine and affective stress responses. From a large group of 771 students, 48 carriers of the short/short (S/S) allele and 48 carriers of the long/long (L/L) allele with the lowest and the highest neuroticism scores (77 females, 19 males; mean age ± SD: 20.6 ± 2 years) were selected and exposed to an acute psychosocial stressor. Mood was assessed before and after the stressor, and salivary cortisol concentrations were measured before and at 20, 30, and 60 min after stressor onset. Acute stress increased salivary cortisol concentration regardless of either 5-HTTLPR genotype or neuroticism, but it caused a less profound negative mood change in L/L compared to S/S-allele carriers with the lowest neuroticism scores. The 5-HTTLPR genotype influences affective reactivity to acute stress conditional upon neuroticism, improving resilience to acute stress in L/L-allele carriers if they do not already possess high cognitive-affective (neuroticism) vulnerability. PMID:21438771

  3. ANTI-HYPOXIA AND ANTI-OXIDATION EFFECTS OF AMINOPHYLLINE ON HUMAN WITH ACUTE HIGH-ALTITUDE EXPOSURE

    Bo Yang; Guang-yi Wang; Bin Chen; Rong-bin Qin; Si Lang Zha Xi; Lian Chen

    2007-01-01

    Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high-altitude exposure.Methods Totally 100 young male army members newly recruited from Sichuan province (400 meters above sea level) were enrolled. They were randomly divided into two groups; 50 in aminophylline group (A group) and 50 in control group (C group). A group and C group orally took aminophylline and placebo respectively for 10 days, 7 days before entering Lhasa (3 658 meters above sea level) by air and 3 days after it Several parameters were measured at three time points: before drug taken, 7 days after drug taken, and 3 days after ascending high altitude. These parameters included serum levels of nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT), hydrogen dioxide (H2O2), lactic acid (LA), as well as arterial oxygen saturation (SO2) , arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Statistical analysis was conducted to compare the difference between two groups with Stata 7.0 software system.Results There were no statistical differences between groups in hypoxia and oxidation indicators before and after drug taken in plain area. Three days after ascending high altitude, the serum levels of SOD, CAT, H2O2, LA, PaCO2 increased in both groups, yet to a much larger degree in C group than A group (P < 0.01); and NO, SO2, PaO2 decreased more markedly in C group (P < 0.05 for NO, P < 0.0001 for SO2 and PaO2).Conclusion Aminophylline has significant anti-hypoxia and anti-oxidation effects at high altitude.

  4. Acute exposure to Catha edulis depresses contractility and induces myocardial infarction in spontaneously contracting, isolated rabbit's heart.

    Al-Hashem, Fahaid H; Dallak, Mohammad A; Nwoye, Luke O; Bin-Jaliah, Ismaeel M; Al-Amri, Hasan S; Rezk, Mahmoud H; Sakr, Hussein F; Shatoor, Abdullah S; Al-Khateeb, Mahmoud

    2012-01-01

    Khat chewing is a recreational habit known to pose major socio-economic and medical problems in countries of Southern Arabia and the Horn of Africa. Among other adverse health effects, khat chewing has been associated with an increased risk of myocardial infarction (MI) in heavy consumers. This study was carried out to examine the direct effects of Catha edulis extract on contractility of spontaneously contracting, isolated rabbit heart and to investigate its mechanism of action. Isolated six rabbit's hearts attached to a Langendorff apparatus were perfused with extract at a constant flow rate and continuously bubbled with a 95% O2/5% CO2 gas mixture. Each heart served as its own control, as responses were recorded before and after administration of C. edulis extract. Varying concentrations of extract (50, 100 and 250 mg/ml) were loaded in the perfusate, their effects recorded and effluent fluid collected for assay of cardiac enzymes. Histological examination of the cardiac tissue was performed at the end of perfusion with 250 mg/ml extract. This study revealed that acute exposure to C. edulis extract exerted negative inotropic and chronotropic effects on isolated hearts. The extract also had a vasoconstrictor effect on coronary vessels, independent of α1 adrenergic receptor stimulation. Histological examination of hearts perfused with 250 mg/ml C. edulis extract revealed the presence of histological changes unique to myocardial infarction, a finding consistent with observed increased levels of cardiac enzymes in perfusates. Thus, we have demonstrated experimentally a direct cardiac depressant- and MI inducing effects of C. edulis extract. These results are consistent with the earlier reported deleterious effects of khat on cardiovascular function among khat chewers. PMID:23961167

  5. Influence of long-term exposure to dietary cadmium on growth, maturation and reproduction of goldfish (subspecies: Prussian carp Carassius auratus gibelio B.)

    Szczerbik, P. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland)]. E-mail: rzbienia@kinga.cyf-kr.edu.pl; Mikolajczyk, T. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland); Sokolowska-Mikolajczyk, M. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland); Socha, M. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland); Chyb, J. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland); Epler, P. [Department of Ichthyobiology and Fisheries, University of Agriculture, 30-199 Cracow-Mydlniki, ul. Spiczakowa 6 (Poland)

    2006-05-01

    The influence of long-term exposure of goldfish to dietary cadmium (Cd) on its accumulation in tissues, growth, ovarian development, luteinizing hormone (LH) secretion and a response to hormonal stimulation of spawning were evaluated. The study was conducted on four groups of females for the period of 3 years, from the age of 10 weeks to second spawning. Four doses of Cd were applied in the feed: 0 (control group), 0.1, 1 and 10 mg Cd g{sup -1} of feed (wet weight). The highest dose of Cd (10 mg g{sup -1}) inhibited growth and caused several behavioural effects. In contrast, lower dose of Cd (1 mg g{sup -1}) stimulated fish growth. The doses of Cd from 0.1 to 1 mg Cd g{sup -1} did not influence ovarian development. The gonado-somatic index (GSI) and histological analysis of ovaries showed no differences in ovarian development between the control group and the groups receiving these doses of Cd. However, in the group receiving the highest Cd dose, GSI decreased. This was associated with persistent, long-lasting elevation of plasma LH levels. Ovulation did not occur in this group. Injections of salmon GnRH-analogue (sGnRHa) alone or with domperidone (a dopamine receptor antagonist) in sexually mature fish caused an increase of LH levels in all groups, although in the group fed with the highest Cd dose the effect was weaker than in the other groups. After the first spawning season, a negative effect of lower Cd doses (0.1 and 1 mg Cd g{sup -1}) on ovarian recrudescence (rebuilding of ovaries) and on the response to the consecutive hormonal stimulation of spawning was observed (lower number of ovulating females). There was a significantly higher content of Cd in the livers of fish than in their muscles. The results of hormonal stimulation of spawning and histological analysis of ovaries suggest that in goldfish cadmium acts mainly at the level of ovary rather than on the pituitary gland. We suppose that in the natural environment cadmium present in the feed can play an

  6. Influence of long-term exposure to dietary cadmium on growth, maturation and reproduction of goldfish (subspecies: Prussian carp Carassius auratus gibelio B.)

    The influence of long-term exposure of goldfish to dietary cadmium (Cd) on its accumulation in tissues, growth, ovarian development, luteinizing hormone (LH) secretion and a response to hormonal stimulation of spawning were evaluated. The study was conducted on four groups of females for the period of 3 years, from the age of 10 weeks to second spawning. Four doses of Cd were applied in the feed: 0 (control group), 0.1, 1 and 10 mg Cd g-1 of feed (wet weight). The highest dose of Cd (10 mg g-1) inhibited growth and caused several behavioural effects. In contrast, lower dose of Cd (1 mg g-1) stimulated fish growth. The doses of Cd from 0.1 to 1 mg Cd g-1 did not influence ovarian development. The gonado-somatic index (GSI) and histological analysis of ovaries showed no differences in ovarian development between the control group and the groups receiving these doses of Cd. However, in the group receiving the highest Cd dose, GSI decreased. This was associated with persistent, long-lasting elevation of plasma LH levels. Ovulation did not occur in this group. Injections of salmon GnRH-analogue (sGnRHa) alone or with domperidone (a dopamine receptor antagonist) in sexually mature fish caused an increase of LH levels in all groups, although in the group fed with the highest Cd dose the effect was weaker than in the other groups. After the first spawning season, a negative effect of lower Cd doses (0.1 and 1 mg Cd g-1) on ovarian recrudescence (rebuilding of ovaries) and on the response to the consecutive hormonal stimulation of spawning was observed (lower number of ovulating females). There was a significantly higher content of Cd in the livers of fish than in their muscles. The results of hormonal stimulation of spawning and histological analysis of ovaries suggest that in goldfish cadmium acts mainly at the level of ovary rather than on the pituitary gland. We suppose that in the natural environment cadmium present in the feed can play an important role in the

  7. 广东省居民主要膳食镉暴露风险的初步评估%Preliminary risk assessment on the dietary exposure of Cd in Guangdong residents

    王桂安; 杨杏芬; 梁春穗; 黄琼; 闻剑; 胡曙光; 李海; 戴昌芳; 王立斌; 张永慧

    2012-01-01

    目的 分析主要食物中镉含量水平,对广东省居民通过膳食途径暴露镉的健康风险进行初步的评估.方法 2009年在全省21地市采集15类食物共2 200份,用石墨炉原子吸收光谱法测定食物中镉的含量,结合居民膳食消费数据,比照镉的暂定每月耐受摄入量(PTMI)及安全限值(MOS)初步评估广东省居民主要食物的镉暴露风险.结果 15类食物中紫菜中镉含量最高,为1 830.0 μg/kg.城乡居民通过大米、蔬菜类、鱼虾类、动物内脏类四类食物每月膳食镉暴露量分别为1 314.6和1 394.3 μg.大米对城市和农村居民膳食镉的贡献率最高,分别为50.1%和64.9%,且以粤北地区最高.结论 主要食品对居民膳食镉的平均贡献水平未超过PTMI值,MOS值大于1,居民膳食镉暴露水平总体上安全.由于我国南方地区居民大米的消费量大及其对居民膳食镉贡献率最高,有必要加强大米可能的镉污染问题研究,并从源头上预防污染.%Objective To analyze the cadmium level of main food, and preliminarily assess the risk of dietary cadmium exposure of people in Guangdong province. Methods In 2009, 2 200 samples of 15 food groups were collected from 21 cities of the province. Cadmium contents in food were determined by using graphite furnace atomic absorption method and then the cadmium exposure from main food was estimated by combining the concentration of cadmium in foods with food consumption data. The health risk was assessed by comparing the cadmium exposure with provisional tolerable monthly intake (PTMI) and the margins of safety (MOS) of cadmium. Results The concentration of cadmium in seaweed was 1830 μg/kg, which was the highest among the 15 food groups being tested. Rice, vegetable, fish, shrimp and animal offal contributed totally 1 314. 6 and 1 394. 3μg cadmium exposure per month in urban and rural residents respectively. Rice, as a most important contributor, contributed 50. 1% and 64

  8. Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

    Poulsen, Sarah S.; Saber, Anne T.; Mortensen, Alicja;

    2015-01-01

    has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18,54 or 162 mu...... g/mouse of small, entangled (CNTsmall, 0.8 +/- 0.1 pm long) or large, thick MWCNTs (CNTLarge, 4 +/- 0.4 mu m long). Liver tissues and plasma were harvested 1,3 and 28 days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess...... hepatic effects. The two MWCNTs induced similar systemic responses despite their different physicochemical properties. APR proteins SAA3 and haptoglobin, plasma total cholesterol and low-density/very low-density lipoprotein were significantly increased following exposure to either MWCNTs. Plasma SAA3...

  9. Production of DNA Double Strand Breaks in Human Cells due to Acute Exposure to Tritiated Water (HTO)

    significant increase in H2AX phosphorylation in primary human fibroblasts. Thus, immunostaining of D3-H2AX may represent a sensitive biomarker of exposure. The scientific literature contains practically no information about the effect of acute exposure from HTO on the integrity of the DNA, and the present work presents some preliminary results on this subject. The investigation on the formation of the Double Strand Breaks was done by the detection of the phosphorylated histone, D3H2AX. For this research we used Human malignant osteoblast MG-63 cells, and normal peripheral blood lymphocytes

  10. Dietary Fiber

    Fiber is a substance in plants. Dietary fiber is the kind you eat. It's a type of carbohydrate. You may also see it listed on a food label as soluble fiber or insoluble fiber. Both types have important health benefits. Good sources of dietary fiber include Whole grains Nuts ...

  11. Association between exposure to radiofrequency electromagnetic fields assessed by dosimetry and acute symptoms in children and adolescents: a population based cross-sectional study

    Radon Katja

    2010-11-01

    Full Text Available Abstract Background The increase in numbers of mobile phone users was accompanied by some concern that exposure to radiofrequency electromagnetic fields (RF EMF might adversely affect acute health especially in children and adolescents. The authors investigated this potential association using personal dosimeters. Methods A 24-hour exposure profile of 1484 children and 1508 adolescents was generated in a population-based cross-sectional study in Germany between 2006 and 2008 (participation 52%. Personal interview data on socio-demographic characteristics, self-reported exposure and potential confounders were collected. Acute symptoms were assessed twice during the study day using a symptom diary. Results Only few of the large number of investigated associations were found to be statistically significant. At noon, adolescents with a measured exposure in the highest quartile during morning hours reported a statistically significant higher intensity of headache (Odd Ratio: 1.50; 95% confidence interval: 1.03, 2.19. At bedtime, adolescents with a measured exposure in the highest quartile during afternoon hours reported a statistically significant higher intensity of irritation in the evening (4th quartile 1.79; 1.23, 2.61, while children reported a statistically significant higher intensity of concentration problems (4th quartile 1.55; 1.02, 2.33. Conclusions We observed few statistically significant results which are not consistent over the two time points. Furthermore, when the 10% of the participants with the highest exposure are taken into consideration the significant results of the main analysis could not be confirmed. Based on the pattern of these results, we assume that the few observed significant associations are not causal but rather occurred by chance.

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

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

    2015-01-01

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

  13. A systematic review of the effect of dietary exposure that could be achieved through normal dietary intake on learning and performance of school-aged children of relevance to UK schools

    Ells, Louisa J.; Hillier, Frances C; Shucksmith, Janet; Crawley, Helen; Harbige, Laurence; Shield, Julian; Wiggins, Andy; Summerbell, Carolyn D

    2008-01-01

    The aim of the present review was to perform a systematic in-depth review of the best evidence from controlled trial studies that have investigated the effects of nutrition, diet and dietary change on learning, education and performance in school-aged children (4-18 years) from the UK and other developed countries. The twenty-nine studies identified for the review examined the effects of breakfast consumption, sugar intake, fish oil and vitamin supplementation and 'good diets'. In summary, th...

  14. Near-term and late biological effects of acute and low-dose-rate continuous gamma-ray exposure in dogs and monkeys

    Monkeys (Macaca mulatta) and dogs (beagle) were given thirteen 100-rad gamma-ray doses at 28-day intervals. The comparative response (inury and recovery) of the hematopoietic system of the two species was observed at 7-day intervals during the exposure regime. At 84 days after the thirteenth gamma-ray dose, the 1300-rad conditioned and control dogs and monkeys were challenged continuously with gamma rays at 35 r/day until death to determine the amount of radiation-induced injry remaining in conditioned animals as a reduction in mean survival time. Dogs (50%) and monkeys (8%) died from injury incurred during conditioning exposures. Thus, the comparative response (in terms of lethality) of dogs and monkeys to dose protraction by acute dose fractionation was similar to what we would expect from a single acute dose. The mean survival times for nonconditioned dogs and monkeys during continuous exposure at 35 R/day were the same (approx. 1400 h). Thus, the hematopoietic response of the two species by this method of dose protraction was not significantly different. Mean survival times of conditioned dogs and monkeys during the continuous 35-R/day gamma-ray challenge exposure were greater (significant in dogs but not in monkeys) than for their control counterparts. Thus, long-term radiation-induced injury was not measurable by this method. Conditioning doses of more than 4 times the acute LD5030 in dogs and approximately 2 times that in monkeys served only to increase both mean survival time and variance in a gamma-ray stress environment with a dose rate of 35 Rat/day

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

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

    2014-03-01

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

  16. Analysis and dietary exposure assessment of the benzoic acid and sodium benzoate of biscuits%饼干中苯甲酸及其钠盐含量分析及其膳食暴露评估

    朱加虹; 王小骊; 袁玉伟; 张玉; 胡桂仙; 董秀金

    2012-01-01

    对市场中210个饼干样品进行苯甲酸及其钠盐含量用HPLC方法进行测定,并对检测数据采用膳食暴露评估方法,评估城市居民的膳食风险。结果显示,婴儿(6-12个月)膳食暴露量为12.25-31.62μg/kgbw·d,其97.5/99百分位值的膳食暴露量为73.99-195.62μg/kgbw·d,建议婴儿(6-12个月)少量食用或食用不含苯甲酸的婴儿饼干。对于1-3岁的幼儿其膳食暴露量为10.25-13.25μg/kgbw·d,在97.5/99百分位值的膳食暴露量为105.24-139.10μg/kgbw·d,食用此类食品的风险是可以接受的。对于3岁以上人群食用此类食品的风险比1-3岁幼儿更小,风险程度更低。另外,饼干中威化和酥性类饼干中苯甲酸的残留水平相对于其他类饼干含量略高,而发酵和韧性类的饼干中苯甲酸的含量相稍低:同时显示江苏产的产品质量相对较好。%The content of benzoic acid and its sodium of 210 biscuits samples in the market was determined by HPLC method, and according the test data, using dietary exposure assessment methods to assess dietary risk urban residents. The results showed that infants (6-12 months) dietary exposure round 12.25-31.62 μg/kg bw· d, the 97.5/99 percentile dietary exposure round 73.99-195.62 μg/kg bw·d, recommends that infants (6 to 12 months) eating a small amount of such biscuits or eating edible acid-free baby biscuits. For children aged 1 to 3, its dietary exposure is round 10.25-13.25 μg/kg bw'd, the 97.5/99 percentile dietary exposure round 105.24-139.10 μg/kg bw·d, consumption of such food risk is acceptable. For people over 3 years old the risk of eating these foods is smaller than children aged 1 to 3, lower level of risk. In addition, wafer biscuit and crisp crackers in the level of benzoic acid residue content relative to other types of biscuits is slightly higher, and fermented and tenacity in the biscuit category with lower

  17. Episodic ozone exposure in adult and Senescent Brown Norway rats: Acute and delayed cardiovascular and thermoregulatory responses

    Setting exposure standards for environmental pollutants may consider the aged as a susceptible population but the few published studies assessing susceptibility of the aged to air pollutants are inconsistent. Episodic ozone (O(3)) is more reflective of potential exposures occurri...

  18. Changes in cholesterol homeostasis and acute phase response link pulmonary exposure to multi-walled carbon nanotubes to risk of cardiovascular disease

    Adverse lung effects following pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) are well documented in rodents. However, systemic effects are less understood. Epidemiological studies have shown increased cardiovascular disease risk after pulmonary exposure to airborne particles, which has led to concerns that inhalation exposure to MWCNTs might pose similar risks. We analyzed parameters related to cardiovascular disease, including plasma acute phase response (APR) proteins and plasma lipids, in female C57BL/6 mice exposed to a single intratracheal instillation of 0, 18, 54 or 162 μg/mouse of small, entangled (CNTSmall, 0.8 ± 0.1 μm long) or large, thick MWCNTs (CNTLarge, 4 ± 0.4 μm long). Liver tissues and plasma were harvested 1, 3 and 28 days post-exposure. In addition, global hepatic gene expression, hepatic cholesterol content and liver histology were used to assess hepatic effects.