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Sample records for long-term tamoxifen exposure

  1. Long-Term Data from 20 Trials Confirm Tamoxifen's Long-Lasting Benefit

    Science.gov (United States)

    Women with estrogen receptor-positive breast cancer who received about 5 years of adjuvant tamoxifen had a lower risk of recurrence in the 15 years after treatment than women who did not receive tamoxifen.

  2. Long-term effects of prenatal progesterone exposure

    DEFF Research Database (Denmark)

    Vedel, Cathrine; Larsen, Helle; Holmskov, Anni

    2016-01-01

    children from 498 pregnancies. PREDICT is a placebo-controlled randomized trial examining progesterone for prevention of preterm delivery in unselected twin pregnancies. Medical histories of the children were reviewed, and neurophysiological development was evaluated by the parent-completed Ages and Stages...... between the groups in number or length of admissions, and we found no overall differences in rates of diagnoses. However, the odds ratio for a diagnosis related to the heart was 1.66 (95%CI 0.80;3.37) in favor of placebo among all children, 2.29 (1.02;5.12) in dichorionic twins, and 8.19 (1......) centile) was decreased in the progesterone group (OR 0.34 (0.14;0.86)). CONCLUSIONS: Second and third trimester exposure to progesterone does not seem to have long-term harmful effects on children, but future studies should focus on cardiac disease in the offspring. CLINICAL TRIAL REGISTRATION: Eudra...

  3. Long-term effects of prenatal exposure to perfluoroalkyl substances on female reproduction

    DEFF Research Database (Denmark)

    Kristensen, Susanne Lund; Ramlau-Hansen, Cecilia; Ernst, Erik

    2013-01-01

    Does prenatal exposure to perfluoroalkyl substances (PFASs) have long-term effects on female reproductive function?.......Does prenatal exposure to perfluoroalkyl substances (PFASs) have long-term effects on female reproductive function?....

  4. Effects of long-term exposure to air pollution on natural-cause mortality

    DEFF Research Database (Denmark)

    Beelen, Rob; Raaschou-Nielsen, Ole; Stafoggia, Massimo

    2013-01-01

    Few studies on long-term exposure to air pollution and mortality have been reported from Europe. Within the multicentre European Study of Cohorts for Air Pollution Effects (ESCAPE), we aimed to investigate the association between natural-cause mortality and long-term exposure to several air...

  5. Adverse Effects of Long Term Exposure to Road Traffic Noise

    NARCIS (Netherlands)

    Y. de Kluizenaar (Yvonne)

    2015-01-01

    markdownabstract__Abstract__ Road traffic is a prominent source of environmental noise exposure in urbanized areas. Because of its common presence, traffic is a source of exposure that is not easy to avoid. As a consequence, it is affecting a substantial proportion of residents in their homes, and

  6. Beta-interferon, retinoids and tamoxifen in metastatic breast cancer: long-term follow-up of a phase II study.

    Science.gov (United States)

    Recchia, Francesco; Sica, Gigliola; Candeloro, Giampiero; Necozione, Stefano; Bisegna, Roberta; Bratta, Massimo; Rea, Silvio

    2009-04-01

    Based on a series of in vitro data, including the additive and/or synergistic antiproliferative effect of interferon and tamoxifen on breast cancer cell lines, and on clinical reports, we designed a pilot phase II study to test the activity and toxicity of simultaneous administration of beta-interferon (beta-IFN), retinoids (R) and tamoxifen (TAM) as a salvage therapy in a group of patients with metastatic breast cancer (MBC). Herein we describe the outcome of this cohort of patients after a median follow-up of 150 months. Sixty-five stage IV breast cancer patients, 13 pre-treated with hormones, 38 with chemotherapy and 15 with both, received, as a salvage therapy, TAM, beta-IFN and R. Among 65 evaluable patients, 36 achieved a clinical response (55.5%) (95% c.i. 42-67.7%). Toxicity was moderate and mainly hepatic. Median progression-free and overall survival, which did not show any statistically significant difference in patients with different estrogen and progesterone receptor content, were 43 months and 47.9 months, respectively. In conclusion, the study shows that long-term treatment with TAM, beta-IFN and R in MBC is feasible, has moderate toxicity and seems to give a long-term benefit, irrespective of the receptorial status.

  7. Seismic Performance of Dry Casks Storage for Long- Term Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Ibarra, Luis [Univ. of Utah, Salt Lake City, UT (United States); Sanders, David [Univ. of Nevada, Reno, NV (United States); Yang, Haori [Oregon State Univ., Corvallis, OR (United States); Pantelides, Chris [Univ. of Utah, Salt Lake City, UT (United States)

    2016-12-30

    The main goal of this study is to evaluate the long-term seismic performance of freestanding and anchored Dry Storage Casks (DSCs) using experimental tests on a shaking table, as well as comprehensive numerical evaluations that include the cask-pad-soil system. The study focuses on the dynamic performance of vertical DSCs, which can be designed as free-standing structures resting on a reinforced concrete foundation pad, or casks anchored to a foundation pad. The spent nuclear fuel (SNF) at nuclear power plants (NPPs) is initially stored in fuel-storage pools to control the fuel temperature. After several years, the fuel assemblies are transferred to DSCs at sites contiguous to the plant, known as Interim Spent Fuel Storage Installations (ISFSIs). The regulations for these storage systems (10 CFR 72) ensure adequate passive heat removal and radiation shielding during normal operations, off-normal events, and accident scenarios. The integrity of the DSCs is important, even if the overpack does not breach, because eventually the spent fuel-rods need to be shipped either to a reprocessing plant or a repository. DSCs have been considered as a temporary storage solution, and usually are licensed for 20 years, although they can be relicensed for operating periods of up to 60 years. In recent years, DSCs have been reevaluated as a potential mid-term solution, in which the operating period may be extended for up to 300 years. At the same time, recent seismic events have underlined the significant risks DSCs are exposed. The consideration of DCSs for storing spent fuel for hundreds of years has created new challenges. In the case of seismic hazard, longer-term operating periods not only lead to larger horizontal accelerations, but also increase the relative effect of vertical accelerations that usually are disregarded for smaller seismic events. These larger seismic demands could lead to casks sliding and tipping over, impacting the concrete pad or adjacent casks. The casks

  8. Tamoxifen

    Science.gov (United States)

    Tamoxifen is also used sometimes to induce ovulation (egg production) in women who do not produce eggs but wish to become pregnant. Tamoxifen is also ... as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant ...

  9. Personality and long term exposure to organic solvents

    Energy Technology Data Exchange (ETDEWEB)

    Lindstroem, K.; Martelin, T.

    1980-01-01

    Personality, especially emotional reactions of two solvent exposed groups and a nonexposed reference group were described by means of 20 formal, content and check-list type of Rorschach variables. Another objective of the study was to explore the suitability and psychological meaning of other types of Rorschach variables than those applied earlier in the field of behavioral toxicology. The factor analyses grouped the applied variables into factors of Productivity, Ego Strength, Control of Emotionality, Defensive Introversion and Aggressiveness. One solvent group, a patient groups (N.53), was characterized by a high number of Organic signs and a low Genetic Level, indicating possible psychoorganic deterioration. The other solvent group, styrene exposed but subjectively healthy (N.98), was characterized by few emotional reactions, low Anxiety and a low number of Neurotic Signs. the long duration of exposure of the solvent patient group (mean 10.2 +/- 8.7 years) was related to variables of the Productivity factor, a finding that indicates a possible better adjustment of those exposed for a longer time. The duration of exposure of the styrene exposed group (mean 4.9 +/- 3.2 years) revealed a very slight relation to personality variables, but the mean urinary mandelic acid concentration, indicating the level of styrene exposure, correlated with increased emotional reactions. For the most part definite causal conclusions could not be drawn because of the cross-sectional design of the study.

  10. Long-Term Exposure to High Corticosterone Levels Inducing a Decrease of Adenylate Kinase 1 Activity

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yu'nan; SHEN Jia; SU Hui; HUANG Yufang; XING Dongming; DU Lijun

    2009-01-01

    Corticosterone, a principal glucocorticoid synthesized in the rodent adrenal cortex, can be cumula-tively toxic to hippocampal neurons, the cause of which is not known. The present study determined whether the cytosol adenylate kinase (AK) system was involved in the neuronal damage induced by long-term exposure to high corticosterone levels. We investigated the effects of long-term exposure to high corticosterone levels on AK1 activity, AK1 mRNA expression, and energy levels in cultured hippocampal neurons. The results show that long-term exposure to high corticosterone levels induces a reduction of the cultured hippocampal neuron viability, significantly reduces energy levels, and causes a time-dependant re-duction of the AK1 activity. These findings indicate that changes in the AK system might be the mechanism underlying neuronal damage induced by long-term exposure to high corticosterone levels.

  11. Effects of long term exposure to hydrogen fluoride on grapevines

    Energy Technology Data Exchange (ETDEWEB)

    Murray, F.

    1984-01-01

    Grapevines Vitis vinifera L. Shiraz were exposed to hydrogen fluoride in open-top chambers for 189 days at mean atmospheric fluoride concentrations of 0.27, 0.17 or 0.07 ..mu..g HFm/sup -3/. Grapevines growing under ambient conditions outside the chambers were exposed to a mean atmospheric fluoride concentration of 0.08 ..mu..g HFm/sup -3/. The maximum leaf fluoride concentrations associated with these treatments were 62, 27, 9 and 15 ..mu..g Fg/sup -1/, respectively. Foliar necrosis was first observed on grapevines exposed to 0.27 and 0.17 ..mu..g HFm/sup -3/ after 83 and 99 days, respectively. Exposure to fluoride increased the fluoride content of berries and peduncles, and reduced leaf chlorophyll a and total chlorophyll concentration at both mid-season and harvest. Exposure to 0.17 ..mu..g HF m/sup -3/ was associated with higher total acid content of grapes than other treatments. Fluoride had no significant effect on bunch weight, number of bunches, grape yield, grape water or potential alcohol content, leaf chlorophyll b or leaf protein concentration. The high accumulation of fluoride in peduncles, but low fluoride accumulation in berries, suggests that the peduncle acts to block the translocation of fluoride from sites of uptake to the fruit. 42 references, 1 figure, 5 tables.

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

    DEFF Research Database (Denmark)

    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).......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)....

  13. Diabetes Incidence and Long-Term Exposure to Air Pollution: A cohort study

    DEFF Research Database (Denmark)

    Andersen, Zorana Jovanovic; Raaschou-Nielsen, Ole; Ketzel, Matthias

    2012-01-01

    Animal and cross-sectional epidemiological studies suggest a link between air pollution and diabetes, whereas the limited prospective data show mixed results. We studied the association between long-term exposure to traffic-related air pollution and incidence of diabetes.......Animal and cross-sectional epidemiological studies suggest a link between air pollution and diabetes, whereas the limited prospective data show mixed results. We studied the association between long-term exposure to traffic-related air pollution and incidence of diabetes....

  14. Long-term particulate matter exposure and mortality: a review of European epidemiological studies

    Directory of Open Access Journals (Sweden)

    Boffetta Paolo

    2009-12-01

    Full Text Available Abstract Background Several studies considered the relation between long-term exposure to particulate matter (PM and total mortality, as well as mortality from cardiovascular and respiratory diseases. Our aim was to provide a comprehensive review of European epidemiological studies on the issue. Methods We searched the Medline database for epidemiological studies on air pollution and health outcomes published between January 2002 and December 2007. We also examined the reference lists of individual papers and reviews. Two independent reviewers classified the studies according to type of air pollutant, duration of exposure and health outcome considered. Among European investigations that examined long-term PM exposure we found 4 cohort studies (considering total and cardiopulmonary mortality, 1 case-control study (considering mortality from myocardial infarction, and 4 ecologic studies (2 studies considering total and cardiopulmonary mortality and 2 studies focused on cardiovascular mortality. Results Measurement indicators of PM exposure used in European studies, including PM10, PM2.5, total suspended particulate and black smoke, were heterogeneous. This notwithstanding, in all analytic studies total mortality was directly associated with long-term exposure to PM. The excesses in mortality were mainly due to cardiovascular and respiratory causes. Three out of 4 ecologic studies found significant direct associations between PM indexes and mortality. Conclusion European studies on long-term exposure to PM indicate a direct association with mortality, particularly from cardiovascular and respiratory diseases.

  15. Recent and long-term occupational noise exposure and salivary cortisol level

    DEFF Research Database (Denmark)

    Stokholm, Zara Ann; Hansen, Åse Marie; Grynderup, Matias Brødsgaard

    2014-01-01

    -term occupational noise exposure and cortisol level measured off work to assess a possible sustained HPA-axis effect. We included 501 industrial, finance, and service workers who were followed for 24h during work, leisure, and sleep. Ambient occupational noise exposure levels were recorded every 5s by personal...... and estimated the noise level at the ear. Salivary cortisol concentration was measured at 20.00h, the following day at awakening, and 30min after awakening on average 5, 14 and 14.5h after finishing work. The mean ambient noise exposure level was 79.9dB(A) [range: 55.0-98.9] and the mean estimated level...... observed no statistically significant exposure response relation between recent, or long-term ambient occupational noise exposure level and any cortisol parameter off work. This was neither the case for recent noise level at the ear. To conclude, neither recent nor long-term occupational noise exposure...

  16. Numerical simulation of gender differences in a long-term microgravity exposure

    Science.gov (United States)

    Perez-Poch, Antoni

    The objective of this work is to analyse and simulate gender differences when individuals are exposed to long-term microgravity. Risk probability of a health impairment which may put in jeopardy a long-term mission is also evaluated. Computer simulations are becoming a promising research line of work, as physiological models become more and more sophisticated and reliable. Technological advances in state-of-the-art hardware technology and software allow nowadays for better and more accurate simulations of complex phenomena, such as the response of the human cardiovascular system to long-term exposure to microgravity. Experimental data for long-term missions are difficult to achieve and reproduce, therefore the predictions of computer simulations are of a major importance in this field. Our approach is based on a previous model developed and implemented in our laboratory (NELME: Numerical Evaluation of Long-term Microgravity Effects). The software simulates the behaviour of the cardiovascular system and different human organs, has a modular architecture, and allows to introduce perturbations such as physical exercise or countermeasures. The implementation is based on a complex electricallike model of this control system, using inexpensive software development frameworks, and has been tested and validated with the available experimental data. Gender differences have been implemented for this specific work, as an adjustment of a number of parameters that are included in the model. Women versus men physiological differences have been therefore taken into account, based upon estimations from the physiology bibliography. A number of simulations have been carried out for long-term exposure to microgravity. Gravity varying from Earth-based to zero, and time exposure are the two main variables involved in the construction of results, including responses to patterns of physical aerobical exercise, and also thermal stress simulating an extra-vehicular activity. Results show

  17. Comments on "Results of a Long-Term Low-Level Microwave Exposure of Rats"

    NARCIS (Netherlands)

    van Rongen, Eric; van Rhoon, Gerard C.; Aleman, Andre; Kelfkens, Gert; Kromhout, Hans; van Leeuwen, Flora E.; Savelkoul, Huub F. J.; Wadman, Wytse J.; van de Weerdt, Rik D. H. J.; Zwamborn, A. Peter M.

    2011-01-01

    In a recent publication in this TRANSACTIONS, Adang et al. concluded that long-term exposure to RF electromagnetic fields may have effects on survival and on blood parameters in rats. The Electromagnetic Fields Committee of the Health Council of The Netherlands disputes this conclusion.

  18. Comments on results of a long-term low-level microwave exposure of rats

    NARCIS (Netherlands)

    Rongen, E. van; Rhoon, G.C. van; Aleman, A.; Kelfkens, G.; Kromhout, H.; Leeuwen, F.E. van; Savelkoul, H.F.J.; Wadman, W.J.; Weerdt, R.D.H.J. van de; Zwamborn, A.P.M.

    2011-01-01

    In a recent publication in this Transactions, Adang concluded that long-term exposure to RF electromagnetic fields may have effects on survival and on blood parameters in rats. The Electromagnetic Fields Committee of the Health Council of The Netherlands disputes this conclusion.

  19. Long-term exposure to air pollution and vascular damage in young adults

    NARCIS (Netherlands)

    Lenters, V.C.; Uiterwaal, C.S.P.M.; Beelen, R.M.J.; Bots, M.L.; Fischer, P.; Brunekreef, B.; Hoek, G.

    2010-01-01

    BACKGROUND: Long-term exposure to ambient air pollution has recently been linked to atherosclerosis and cardiovascular events. There are, however, very limited data in healthy young people. We examined the association between air pollutants and indicators of vascular damage in a cohort of young

  20. Comments on "results of a long-term low-level microwave exposure of rats'

    NARCIS (Netherlands)

    Rongen, E.; Rhoon, van G.C.; Aleman, A.; Kelfkens, G.; Kromhout, H.; Leeuwen, van F.E.; Savelkoul, H.F.J.

    2011-01-01

    In a recent publication in this Transactions, Adang et al. concluded that long-term exposure to RF electromagnetic fields may have effects on survival and on blood parameters in rats. The Electromagnetic Fields Committee of the Health Council of The Netherlands disputes this conclusion

  1. Long-term exposure to road traffic noise and incident diabetes

    DEFF Research Database (Denmark)

    Sørensen, Mette; Andersen, Zorana Jovanovic; Nordsborg, Rikke B

    2013-01-01

    Road traffic noise at normal urban levels can lead to stress and sleep disturbances. Both excess of stress hormones and reduction in sleep quality and duration may lead to higher risk for type 2 diabetes.Objective: We investigated whether long-term exposure to residential road traffic noise...

  2. Comments on "results of a long-term low-level microwave exposure of rats'

    NARCIS (Netherlands)

    Rongen, E.; Rhoon, van G.C.; Aleman, A.; Kelfkens, G.; Kromhout, H.; Leeuwen, van F.E.; Savelkoul, H.F.J.

    2011-01-01

    In a recent publication in this Transactions, Adang et al. concluded that long-term exposure to RF electromagnetic fields may have effects on survival and on blood parameters in rats. The Electromagnetic Fields Committee of the Health Council of The Netherlands disputes this conclusion

  3. The Long-Term Economic Impact of in Utero and Postnatal Exposure to Malaria

    Science.gov (United States)

    Barreca, Alan I.

    2010-01-01

    I use an instrumental-variables identification strategy and historical data from the United States to estimate the long-term economic impact of in utero and postnatal exposure to malaria. My research design matches adults in the 1960 Decennial Census to the malaria death rate in their respective state and year of birth. To address potential…

  4. The Long-Term Economic Impact of in Utero and Postnatal Exposure to Malaria

    Science.gov (United States)

    Barreca, Alan I.

    2010-01-01

    I use an instrumental-variables identification strategy and historical data from the United States to estimate the long-term economic impact of in utero and postnatal exposure to malaria. My research design matches adults in the 1960 Decennial Census to the malaria death rate in their respective state and year of birth. To address potential…

  5. Long-term exposure to road traffic noise and myocardial infarction.

    Science.gov (United States)

    Selander, Jenny; Nilsson, Mats E; Bluhm, Gösta; Rosenlund, Mats; Lindqvist, Magnus; Nise, Gun; Pershagen, Göran

    2009-03-01

    An association has been reported between long-term exposure to road traffic noise and the risk of myocardial infarction (MI), but the evidence is limited and inconclusive. No previous study has simultaneously analyzed the role of exposure to noise and air pollution from road traffic in the risk of MI. A population-based case-control study on MI was conducted 1992-1994 in Stockholm County. Participants answered a questionnaire and underwent a physical examination. Residential exposure to noise and air pollution from road traffic between 1970 and 1992-1994 was assessed for 3666 participants (1571 cases of MI and 2095 controls), based on residential history combined with information on traffic intensity and distance to nearby roads. Information was also obtained on factors potentially affecting the relationship between noise exposure and MI, such as noise annoyance. The correlation between long-term individual exposure to noise and air pollution from traffic was high (r = 0.6). The adjusted odds ratio for MI associated with long-term road traffic noise exposure of 50 dBA or higher was 1.12 (95% confidence interval = 0.95-1.33). In a subsample, defined by excluding persons with hearing loss or exposure to noise from other sources, the corresponding odds ratio was 1.38 (1.11-1.71), with a positive exposure-response trend. No strong effect modification was apparent by sex or cardiovascular risk factors, including air pollution from road traffic. The results lend some support to the hypothesis that long-term exposure to road traffic noise increases the risk for MI.

  6. Bacterial bioluminescence response to long-term exposure to reverse osmosis treated effluents from dye industries.

    Science.gov (United States)

    Ravindran, J; Manikandan, B; Shirodkar, P V; Francis, K X; Mani Murali, R; Vethamony, P

    2014-10-01

    The bacterial bioluminescence assay is one of the novel means for toxicity detection. The bioluminescence response of 2 marine bioluminescent bacteria was tested upon their long-term exposure to 9 different reverse osmosis (RO) rejects with varying chemical composition sampled from various dye industries. Bioluminescent bacteria were cultured in the RO reject samples, at different concentrations, and their growth rate and luminescence was measured for 24 h. The RO reject samples caused sublethal effects upon exposure and retarded the growth of bacteria, confirming their toxic nature. Further, continuation of the exposure showed that the initial luminescence, though reduced, recovered and increased beyond the control cultures irrespective of cell density, and finally decreased once again. The present study emphasizes the need of evolving a long-term exposure assay and shows that the method followed in this study is suitable to evaluate the toxicants that exert delayed toxicity, using lower concentrations of toxicants as well as coloured samples.

  7. Long-Term Exposure to Traffic-Related Air Pollution and Risk of Incident Atrial Fibrillation

    DEFF Research Database (Denmark)

    Monrad, Maria; Sajadieh, Ahmad; Christensen, Jeppe Schultz

    2017-01-01

    of first-ever hospital admission for atrial fibrillation from enrolment to end of follow-up in 2011. For all cohort members, exposure to traffic-related air pollution assessed as nitrogen dioxide (NO2) and nitrogen oxides (NOx) was estimated at all present and historical residential addresses from 1984...... to 2011 using a validated dispersion model. We used Cox proportional hazard model to estimate associations between long-term residential exposure to NO2 and NOx and risk of atrial fibrillation, after adjustment for lifestyle and socioeconomic position. RESULTS: A 10 µg/m(3) higher 10-years' time......-weighted mean exposure to NO2 preceding diagnosis was associated with an 8% higher risk of atrial fibrillation (incidence rate ratio: 1.08; 95% confidence interval: 1.01-1.14) in adjusted analysis. Though weaker, similar results were obtained for long-term residential exposure to NOx. We found no clear...

  8. Masculinization and reproductive effects in western mosquitofish (Gambusia affinis) after long-term exposure to androstenedione.

    Science.gov (United States)

    Hou, Li-Ping; Yang, Yang; Shu, Hu; Ying, Guang-Guo; Zhao, Jian-Liang; Fang, Gui-Zhen; Xin, Li; Shi, Wen-Jun; Yao, Li; Cheng, Xue-Mei

    2017-09-12

    Androstenedione (AED) is a naturally occurring steroid hormone. It is metabolized to potent androgens, which may induce androgenic effects in fish. However, little is known whether and how the androgens interfere with the fish gonadal development and reproduction. This study aimed at demonstrating the effects of long-term AED exposure on reproduction and development in mosquitofish (Gambusia affinis). The growth, development and several morphological endpoints, including the segment number and length of anal fin, histological changes of gonads and liver, were evaluated in mosquitofish during development from fertilized embryo to adulthood (180 days) after exposure of AED at environmentally relevant concentrations. We found that the growth (length, body weight and condition factor) of fish was negatively correlated with AED concentration in females, but not in males. The significant elongation of the ray and increment of segment numbers in the anal fin, were detected in all mosquitofish after exposure. Moreover, AED exposure (0.4gµ/L) caused damages in gonads and reduced the number of pregnant females. These findings indicate that AED has adverse effects on the growth and development of the western mosquitofish after long-term exposure (180d). Long-term exposure (180d) to AED, including environmentally relevant concentration (0.4µg/L and 4µg/L), induced masculinization in female mosquitofish under the experimental conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Stroke and Long-Term Exposure to Outdoor Air Pollution From Nitrogen Dioxide A Cohort Study

    DEFF Research Database (Denmark)

    Andersen, Zorana Jovanovic; Kristiansen, Luise Cederkvist; Andersen, Klaus K.

    2012-01-01

    Background and Purpose-Years of exposure to tobacco smoke substantially increase the risk for stroke. Whether long-term exposure to outdoor air pollution can lead to stroke is not yet established. We examined the association between long-term exposure to traffic-related air pollution and incident...... to traffic-related air pollution may contribute to the development of ischemic but not hemorrhagic stroke, especially severe ischemic strokes leading to death within 30 days....... and fatal stroke in a prospective cohort study.Methods-We followed 57 053 participants of the Danish Diet, Cancer and Health cohort in the Hospital Discharge Register for the first-ever hospital admission for stroke (incident stroke) between baseline (1993-1997) and 2006 and defined fatal strokes as death...

  10. Effects of Long-term Exposure to Hydrogen Sulfide on Human Red Blood Cells

    Directory of Open Access Journals (Sweden)

    A Saeedi

    2015-01-01

    Full Text Available Background: Hydrogen sulfide (H2S exhibits both physiological and toxicological roles in the biological systems. Acute exposure to high levels of H2S is life threatening while long-term exposure to ambient levels of H2S elicits human health effects. Objective: To study the harmful effects of long-term exposure to low levels of H2S on human blood cells. Methods: 110 adult workers from Iran who were occupationally exposed to 0–90 ppb H2S for 1–30 years were studied. The participants aged between 18 and 60 years and were exposed directly or indirectly to sulfur compounds (exposed group. The origin of H2S was natural gas processing plants. A control group consisting of 110 males who were not in contact with H2S was also studied. For all participants, hematological profile including total hemoglobin and red blood cell count and sulfhemoglobin, methemoglobin levels were measured. Results: Among all parameters evaluated in this study the mean methemoglobin and sulfhemoglobin levels were significantly higher among workers who were exposed to sulfur compounds than the control group. Major differences throughout the study period for sulfhemoglobinemia among exposed groups were observed. Conclusion: Long-term exposure to even low levels of H2S in workplaces may have potential harmful effects on human health.

  11. Effects of long-term high temperature exposure on the microstructure of Haynes alloy 230

    Energy Technology Data Exchange (ETDEWEB)

    Veverkova, J.; Strang, A.; Atkinson, H.V. [Leicester Univ. (United Kingdom). Dept. of Engineering; Marchant, G.R. [Siemens Industrial Turbomachinery Ltd., Lincoln (United Kingdom)

    2010-07-01

    Haynes Alloy 230 was specifically designed to have excellent long-term thermal stability and resistance to the precipitation of damaging phases. This paper describes in detail studies on the effects of long-term high temperature exposure on the hardness, microstructural changes and tensile properties of thermally exposed samples of Haynes Alloy 230. The samples from the 2mm thick sheet material have been investigated using X-Ray diffraction and advanced electron microscopy techniques (FEGSEM, TEM etc.). The evolution of the precipitating phases was monitored across a wide range of temperatures (from 500 C to 1170 C) and durations (from 24 hours up to 30000 hours) and several key phases have been identified. In addition to the primary W-rich carbide and the precipitation of Cr-rich M{sub 23}C{sub 6}, a new brittle phase/carbide was observed within the microstructure at the highest exposure temperatures (above 930 C). (orig.)

  12. Early Life Fructose Exposure and Its Implications for Long-Term Cardiometabolic Health in Offspring

    Directory of Open Access Journals (Sweden)

    Jia Zheng

    2016-11-01

    Full Text Available It has become increasingly clear that maternal nutrition can strongly influence the susceptibility of adult offspring to cardiometabolic disease. For decades, it has been thought that excessive intake of fructose, such as sugar-sweetened beverages and foods, has been linked to increased risk of obesity, type 2 diabetes, and cardiovascular disease in various populations. These deleterious effects of excess fructose consumption in adults are well researched, but limited data are available on the long-term effects of high fructose exposure during gestation, lactation, and infancy. This review aims to examine the evidence linking early life fructose exposure during critical periods of development and its implications for long-term cardiometabolic health in offspring.

  13. Susceptibility Factors Relevant for the Association Between Long-Term Air Pollution Exposure and Incident Asthma.

    Science.gov (United States)

    Burte, Emilie; Nadif, Rachel; Jacquemin, Bénédicte

    2016-03-01

    In this review, we identified 15 studies in children and 10 studies in adults that assessed the association between long-term exposure to air pollution and incident asthma and that conducted stratified analyses to explore potential susceptibility factors. Overall, adult never-/former smokers seem to be at higher risk of incident asthma due to air pollution. Children without atopy and children from low socioeconomic status families also seem to be at higher risk of incident asthma due to air pollution. While interaction between air pollution and genes involved in the response to oxidative stress pathways have been explored, results are somewhat inconsistent and in need of replication. To evaluate interactions, large sample sizes are necessary, and much more research, including data pooling from existing studies, is needed to further explore susceptibility factors for asthma incidence due to long-term air pollution exposure.

  14. Natural Cause Mortality and Long-Term Exposure to Particle Components

    DEFF Research Database (Denmark)

    Beelen, Rob; Hoek, Gerard; Raaschou-Nielsen, Ole

    2015-01-01

    BACKGROUND: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. OBJECTIVES: Our aim was to study the association between natural...... of the associations between mortality and air pollution were conducted using Cox proportional hazards models using a common protocol followed by meta-analysis. RESULTS: The total study population consisted of 291,816 participants, of which 25,466 died from a natural cause during follow-up (average time of follow...... was reduced. CONCLUSIONS: Long-term exposure to PM2.5 sulfur was associated with natural cause mortality. This association was robust to adjustment for other pollutants and PM2.5....

  15. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008.

    Science.gov (United States)

    Li, Chaoyang; Balluz, Lina S; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R

    2016-02-01

    Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P life expectancy in males (95% CI: -0.30 to -0.19) and 0.21 year in females (95% CI: -0.25 to -0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy.

  16. Realistic pesticide exposure through water and food amplifies long-term effects in a Limnephilid caddisfly.

    Science.gov (United States)

    Rasmussen, Jes Jessen; Reiber, Lena; Holmstrup, Martin; Liess, Matthias

    2017-02-15

    Pesticides are increasingly recognized as relevant stressors in stream ecosystems. Stream biota is exposed to pesticides with low water solubility, e.g. pyrethroid insecticides, via water, habitat, and food. However, long-term effects of simultaneous exposure pathways are unknown. In this context, we conducted a microcosm experiment with the caddisfly Anabolia nervosa exposing the larvae to the pyrethroid insecticide esfenvalerate (EFV) at 0.1 and 1.0μgL(-1) via (i) water, (ii) food or a (iii) combination of water and food. Combined exposure through water and food significantly reduced emergence by 60% and significantly postponed emergence timing at the highest EFV level, whereas none of the single-phase exposures showed significant effects. Moreover, our study revealed that successfully emerged females from the highest biphasic treatment level were characterised by altered composition of storage lipids indicative of reduced energy reserves. Consequently, a realistic test scenario that represents simultaneous exposure of organisms and their food may reveal substantially increased long term effects of pyrethroids when compared with current ecological risk assessment applying only single phase exposure. We recommend that relevant concurrent exposure routes of pesticides should be considered in order to derive realistic regulatory acceptable concentrations of pesticides. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Long-term exposure to elemental constituents of particulate matter and cardiovascular mortality in 19 European cohorts

    DEFF Research Database (Denmark)

    Wang, Meng; Beelen, Rob; Stafoggia, Massimo

    2014-01-01

    Associations between long-term exposure to ambient particulate matter (PM) and cardiovascular (CVD) mortality have been widely recognized. However, health effects of long-term exposure to constituents of PM on total CVD mortality have been explored in a single study only....

  18. Long-term exposure to elemental constituents of particulate matter and cardiovascular mortality in 19 European cohorts

    DEFF Research Database (Denmark)

    Wang, Meng; Beelen, Rob; Stafoggia, Massimo

    2014-01-01

    Associations between long-term exposure to ambient particulate matter (PM) and cardiovascular (CVD) mortality have been widely recognized. However, health effects of long-term exposure to constituents of PM on total CVD mortality have been explored in a single study only....

  19. Long-term air pollution exposure and cardio- respiratory mortality: a review

    Science.gov (United States)

    2013-01-01

    Current day concentrations of ambient air pollution have been associated with a range of adverse health effects, particularly mortality and morbidity due to cardiovascular and respiratory diseases. In this review, we summarize the evidence from epidemiological studies on long-term exposure to fine and coarse particles, nitrogen dioxide (NO2) and elemental carbon on mortality from all-causes, cardiovascular disease and respiratory disease. We also summarize the findings on potentially susceptible subgroups across studies. We identified studies through a search in the databases Medline and Scopus and previous reviews until January 2013 and performed a meta-analysis if more than five studies were available for the same exposure metric. There is a significant number of new studies on long-term air pollution exposure, covering a wider geographic area, including Asia. These recent studies support associations found in previous cohort studies on PM2.5. The pooled effect estimate expressed as excess risk per 10 μg/m3 increase in PM2.5 exposure was 6% (95% CI 4, 8%) for all-cause and 11% (95% CI 5, 16%) for cardiovascular mortality. Long-term exposure to PM2.5 was more associated with mortality from cardiovascular disease (particularly ischemic heart disease) than from non-malignant respiratory diseases (pooled estimate 3% (95% CI −6, 13%)). Significant heterogeneity in PM2.5 effect estimates was found across studies, likely related to differences in particle composition, infiltration of particles indoors, population characteristics and methodological differences in exposure assessment and confounder control. All-cause mortality was significantly associated with elemental carbon (pooled estimate per 1 μg/m3 6% (95% CI 5, 7%)) and NO2 (pooled estimate per 10 μg/m3 5% (95% CI 3, 8%)), both markers of combustion sources. There was little evidence for an association between long term coarse particulate matter exposure and mortality, possibly due to the small number of

  20. Long-term exposure to auto exhaust and other pollutant mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, T.E.; Moorman, W.J.; Yang, Y.; Stara, J.F.

    1974-08-01

    Research report:beagles were exposed 16 hr daily for 61 months to raw and photochemically reacted auto exhaust, nitrogen oxides, and sulfur, alone and in combination. exposure to nitrogen oxides reduced diffusion capacity and peak expiratory flow. raw exhaust and raw exhaust plus sulfur oxides produced pulmonary hyperinflation. irradiated auto exhaust also impaired ventilatory distribution. lung volumes, compliances, and maximal breathing capacity were not impaired by the experimental atmospheres. such chronic pulmonary changes resulting from long-term, low-level exposure to ubiquitous urban air pollutants denote potential, serious health hazards. (l diagram, 16 references, 3 tables)

  1. Long-term human exposure to lead from different media and intake pathways

    DEFF Research Database (Denmark)

    Pizzol, Massimo; Thomsen, Marianne; Andersen, Mikael Skou

    2010-01-01

    , and predicting the resulting internal body exposure levels and effects that occur under long-term exposure conditions. In this paper, a modeling approach is used to meet these challenges with reference to Danish exposure conditions. Levels of lead content in various media have been coupled with data for lead......Lead (Pb) is well known as an environmental pollutant: it can accumulate in various media, so actual lead exposure reflects both historical and present contaminations. Two main challenges then emerge: obtaining updated information to gain an overall picture of the sources of exposure......–internalconcentration relationships for the direct linkage between lead in environmental media and resultingconcentrations of lead in blood are then presented....

  2. Evaluation of effects of long term exposure on lethal toxicity with mammals.

    Science.gov (United States)

    Verma, Vibha; Yu, Qiming J; Connell, Des W

    2014-02-01

    The relationship between exposure time (LT50) and lethal exposure concentration (LC50) has been evaluated over relatively long exposure times using a novel parameter, Normal Life Expectancy (NLT), as a long term toxicity point. The model equation, ln(LT50) = aLC50(ν) + b, where a, b and ν are constants, was evaluated by plotting lnLT50 against LC50 using available toxicity data based on inhalation exposure from 7 species of mammals. With each specific toxicant a single consistent relationship was observed for all mammals with ν always mammals and then be extended to estimate toxicity at any exposure time with other mammals. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  3. Long-term pulmonary complications of chemical weapons exposure in former poison gas factory workers.

    Science.gov (United States)

    Nishimura, Yoshifumi; Iwamoto, Hiroshi; Ishikawa, Nobuhisa; Hattori, Noboru; Horimasu, Yasushi; Ohshimo, Shinichiro; Fujitaka, Kazunori; Kondo, Keiichi; Hamada, Hironobu; Awai, Kazuo; Kohno, Nobuoki

    2016-07-01

    Sulfur mustard (SM) and lewisite are vesicant chemical warfare agents that can cause skin blistering and chronic lung complications. During 1929-1945, a Japanese factory produced poisonous gases, which included SM, lewisite and other chemical weapons. The aim of this study was to investigate the chest computed tomography (CT) findings among long-term survivors who worked at this factory. During 2009-2012, we evaluated chest CT findings from 346 long-term survivors who worked at the poison gas factory. Skin lesions were used as an indicator of significant exposure to vesicant agents. Among the 346 individuals, 53 (15%) individuals experienced skin lesions while working at the factory, and chest CT revealed abnormal findings in 179 individuals (52%). Emphysema was the most common CT finding and was observed in 75 individuals (22%), while honeycombing was observed in 8 individuals (2%). Emphysema and honeycombing were more prevalent among individuals with skin lesions, compared to individuals without skin lesions. Multivariate analyses revealed significant associations between the presence of emphysema and skin lesions (p = 0.008). Among individuals who never smoked, individuals with skin lesions (n = 26) exhibited a significantly higher rate of emphysema, compared to individuals without skin lesions (n = 200) (35% versus 7%, respectively; p factory, a history of skin lesions was associated with the presence of emphysema, even among never smokers, which suggests that emphysema might be a long-term complication of exposure to chemical warfare agents.

  4. Early Life Exposure to Fructose and Offspring Phenotype: Implications for Long Term Metabolic Homeostasis

    Directory of Open Access Journals (Sweden)

    Deborah M. Sloboda

    2014-01-01

    Full Text Available The consumption of artificially sweetened processed foods, particularly high in fructose or high fructose corn syrup, has increased significantly in the past few decades. As such, interest into the long term outcomes of consuming high levels of fructose has increased significantly, particularly when the exposure is early in life. Epidemiological and experimental evidence has linked fructose consumption to the metabolic syndrome and associated comorbidities—implicating fructose as a potential factor in the obesity epidemic. Yet, despite the widespread consumption of fructose-containing foods and beverages and the rising incidence of maternal obesity, little attention has been paid to the possible adverse effects of maternal fructose consumption on the developing fetus and long term effects on offspring. In this paper we review studies investigating the effects of fructose intake on metabolic outcomes in both mother and offspring using human and experimental studies.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  6. An investigation of moving bed biofilm reactor nitrification during long-term exposure to cold temperatures.

    Science.gov (United States)

    Hoang, Valerie; Delatolla, Robert; Laflamme, Edith; Gadbois, Alain

    2014-01-01

    Biological treatment is the most common and economical means of ammonia removal in wastewater; however, nitrification rates can become completely impeded at cold temperatures. Attached growth processes and, specifically, moving bed biofilm reactors (MBBRs) have shown promise with respect to low-temperature nitrification. In this study, two laboratory MBBRs were used to investigate MBBR nitrification rates at 20, 5, and 1 degree C. Furthermore, the solids detached by the MBBR reactors were investigated and Arrhenius temperature correction models used to predict nitrification rates after long-term low-temperature exposure was evaluated. The nitrification rate at 5 degrees C was 66 +/- 3.9% and 64 +/- 3.7% compared to the rate measured at 20 degrees C for reactors 1 and 2, respectively. The nitrification rates at 1 degree C over a 4-month exposure period compared to the rate at 20 degrees C were 18.7 +/- 5.5% and 15.7 +/- 4.7% for the two reactors. The quantity of solids detached from the MBBR biocarriers was low and the mass of biofilm per carrier did not vary significantly at 20 degrees C compared to that after long-term exposure at 1 degree C. Lastly, a temperature correction model based on exposure time to cold temperatures showed a strong correlation to the calculated ammonia removal rates relative to 20 degrees C following a gradual acclimatization period to cold temperatures.

  7. Assessing the risk of chronic lung injury attributable to long-term ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Whitfield, R.G. (Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.); Wallsten, T.S. (North Carolina Univ., Chapel Hill, NC (United States). L.L. Thurstone Psychometric Lab.); Winkler, R.L. (Duke Univ., Durham, NC (United States). Fuqua School of Business); Richmond, H.M. (Environmental Protection Agency, Research Triangle Park, NC (United States). O

    1991-07-01

    The research described here is part of a larger risk assessment project sponsored by the US Environmental Protection Agency. The purpose of this research is to characterize scientific judgment regarding the risk of chronic lung injury to children aged 8 through 16 and adult outdoor workers due to long-term ozone exposure in areas with patterns of exposure similar to those found in southern California and the Northeast. The qualitative and quantitative judgments resulting from the work will not be used in the ongoing review of the ozone primary ambient air quality standard. They will instead be used to inform policymakers and the public about the possible health implications of long-term exposure to ozone. Our measure of injury is the incidence of mild or moderate lesions in the centriacinar region of the lung. The probabilities over population response rates were elicited from six health experts actively researching ozone-induced lung injury. We describe our approach and present the results in the form of judgmental probability distributions and associated qualitative comments over the population response rates for formation of lesions induced by exposure to ozone. 19 refs., 15 figs., 1 tab.

  8. Response of Simulated Drinking Water Biofilm Mechanical and Structural Properties to Long-Term Disinfectant Exposure.

    Science.gov (United States)

    Shen, Yun; Huang, Conghui; Monroy, Guillermo L; Janjaroen, Dao; Derlon, Nicolas; Lin, Jie; Espinosa-Marzal, Rosa; Morgenroth, Eberhard; Boppart, Stephen A; Ashbolt, Nicholas J; Liu, Wen-Tso; Nguyen, Thanh H

    2016-02-16

    Mechanical and structural properties of biofilms influence the accumulation and release of pathogens in drinking water distribution systems (DWDS). Thus, understanding how long-term residual disinfectants exposure affects biofilm mechanical and structural properties is a necessary aspect for pathogen risk assessment and control. In this study, elastic modulus and structure of groundwater biofilms was monitored by atomic force microscopy (AFM) and optical coherence tomography (OCT) during three months of exposure to monochloramine or free chlorine. After the first month of disinfectant exposure, the mean stiffness of monochloramine- or free-chlorine-treated biofilms was 4 to 9 times higher than those before treatment. Meanwhile, the biofilm thickness decreased from 120 ± 8 μm to 93 ± 6-107 ± 11 μm. The increased surface stiffness and decreased biofilm thickness within the first month of disinfectant exposure was presumably due to the consumption of biomass. However, by the second to third month during disinfectant exposure, the biofilm mean stiffness showed a 2- to 4-fold decrease, and the biofilm thickness increased to 110 ± 7-129 ± 8 μm, suggesting that the biofilms adapted to disinfectant exposure. After three months of the disinfectant exposure process, the disinfected biofilms showed 2-5 times higher mean stiffness (as determined by AFM) and 6-13-fold higher ratios of protein over polysaccharide, as determined by differential staining and confocal laser scanning microscopy (CLSM), than the nondisinfected groundwater biofilms. However, the disinfected biofilms and nondisinfected biofilms showed statistically similar thicknesses (t test, p > 0.05), suggesting that long-term disinfection may not significantly remove net biomass. This study showed how biofilm mechanical and structural properties vary in response to a complex DWDS environment, which will contribute to further research on the risk assessment and control of biofilm-associated-pathogens in DWDS.

  9. In utero and early life arsenic exposure in relation to long-term health and disease

    Energy Technology Data Exchange (ETDEWEB)

    Farzan, Shohreh F.; Karagas, Margaret R. [Children' s Environmental Health and Disease Prevention Research Center at Dartmouth, Hanover, NH 03755 (United States); Section of Biostatistics and Epidemiology, Department of Community and Family Medicine and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756 (United States); Chen, Yu, E-mail: yu.chen@nyumc.org [Department of Population Health, New York University School of Medicine, New York, NY 10016 (United States)

    2013-10-15

    Background: There is a growing body of evidence that prenatal and early childhood exposure to arsenic from drinking water can have serious long-term health implications. Objectives: Our goal was to understand the potential long-term health and disease risks associated with in utero and early life exposure to arsenic, as well as to examine parallels between findings from epidemiological studies with those from experimental animal models. Methods: We examined the current literature and identified relevant studies through PubMed by using combinations of the search terms “arsenic”, “in utero”, “transplacental”, “prenatal” and “fetal”. Discussion: Ecological studies have indicated associations between in utero and/or early life exposure to arsenic at high levels and increases in mortality from cancer, cardiovascular disease and respiratory disease. Additional data from epidemiologic studies suggest intermediate effects in early life that are related to risk of these and other outcomes in adulthood. Experimental animal studies largely support studies in humans, with strong evidence of transplacental carcinogenesis, atherosclerosis and respiratory disease, as well as insight into potential underlying mechanisms of arsenic's health effects. Conclusions: As millions worldwide are exposed to arsenic and evidence continues to support a role for in utero arsenic exposure in the development of a range of later life diseases, there is a need for more prospective studies examining arsenic's relation to early indicators of disease and at lower exposure levels. - Highlights: • We review in utero and early-life As exposure impacts on lifelong disease risks. • Evidence indicates that early-life As increases risks of lung disease, cancer and CVD. • Animal work largely parallels human studies and may lead to new research directions. • Prospective studies and individual exposure assessments with biomarkers are needed. • Assessing intermediary

  10. Long-Term Cognitive and Neuropsychiatric Consequences of Repetitive Concussion and Head-Impact Exposure.

    Science.gov (United States)

    McAllister, Thomas; McCrea, Michael

    2017-03-01

    Initially, interest in sport-related concussion arose from the premise that the study of athletes engaged in sports associated with high rates of concussion could provide insight into the mechanisms, phenomenology, and recovery from mild traumatic brain injury. Over the last decade, concerns have focused on the possibility that, for some athletes, repetitive concussions may raise the long-term risk for cognitive decline, neurobehavioral changes, and neurodegenerative disease. First conceptualized as a discrete event with variable recovery trajectories, concussion is now viewed by some as a trigger of neurobiological events that may influence neurobehavioral function over the course of the life span. Furthermore, advances in technology now permit us to gain a detailed understanding of the frequency and intensity of repetitive head impacts associated with contact sports (eg, football, ice hockey). Helmet-based sensors can be used to characterize the kinematic features of concussive impacts, as well as the profiles of typical head-impact exposures experienced by athletes in routine sport participation. Many large-magnitude impacts are not associated with diagnosed concussions, whereas many diagnosed concussions are associated with more modest impacts. Therefore, a full understanding of this topic requires attention to not only the effects of repetitive concussions but also overall exposure to repetitive head impacts. This article is a review of the current state of the science on the long-term neurocognitive and neurobehavioral effects of repetitive concussion and head-impact exposure in contact sports.

  11. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Pope III, C.A.; Burnett, R.T.; Thun, M.J.; Calle, E.E.; Krewski, D.; Ito, K.; Thurston, G.D. [Brigham Young University, Provo, UT (United States)

    2003-03-06

    A study was conducted to the relationship between long-term exposure to fine particulate air pollution and all-cause, lung cancer, and cardiopulmonary mortality. Vital status and cause of death data were collected by the American Cancer Society as part of the Cancer Prevention II study, an ongoing prospective mortality study, which enrolled approximately 1.2 million adults in 1982. Participants completed a questionnaire detailing individual risk factor data (age, sex, race, weight, height, smoking history, education, marital status, diet, alcohol consumption, and occupational exposures). The risk factor data for approximately 500 000 adults were linked with air pollution data for metropolitan areas throughout the United States and combined with vital status and cause of death data through December 31, 1998. Fine particulate and sulfur oxide-related pollution were found to be associated with all-cause, lung cancer, and cardiopulmonary mortality. Each 10-{mu}g/m{sup 3} elevation in fine particulate air pollution was associated with approximately a 4%, 6%, and 8% increased risk of all-cause, cardiopulmonary, and lung cancer mortality, respectively. Measures of coarse particle fraction and total suspended particles were not consistently associated with mortality. It was concluded that long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopulmonary and lung cancer mortality. 31 refs., 5 figs., 2 tabs.

  12. Mitochondrial proteomic alterations caused by long-term low-dose copper exposure in mouse cortex.

    Science.gov (United States)

    Lin, Xuemei; Wei, Gang; Huang, Zhijun; Qu, Zhongsen; Huang, Xinfeng; Xu, Hua; Liu, Jianjun; Zhuang, Zhixiong; Yang, Xifei

    2016-11-30

    Mitochondrial dysfunction is involved in neurotoxicity caused by exposure of various chemicals such as copper. However, the effects of long-term low-dose copper exposure on mitochondrial proteome remain unclear. In this study, we found the treatment of copper (0.13ppm copper sulfate in drinking water) for 12 months caused abnormal expression of a total of 13 mitochondrial proteins (7 up-regulated and 6 down-regulated) as revealed by two-dimensional electrophoresis coupled with mass spectrometry in mouse cortex. Protein functional analysis revealed that these differentially expressed proteins mainly included apoptosis-associated proteins, axon guidance-associated proteins, axonogenesis-associated proteins and mitochondrial respiratory chain complex. Among these differentially expressed mitochondrial proteins, GRP75 (75kDa glucose-regulated protein) and GRP78 (78kDa glucose-regulated protein) were found to be significantly down-regulated as confirmed by Western-blot analysis. The down-regulation of GRP75 was shown to promote apoptosis. The down-regulation of GRP78/BiP could up-regulate endoplasmic reticulum (ER) stress mediators and thus cause apoptosis. Our study suggested that these differentially expressed mitochondrial proteins such as GRP75 and GRP78 could be involved in neurotoxicity caused by long-term low-dose copper exposure and serve as potential molecular targets for the treatment of copper neurotoxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Long-Term Exposure to Ambient Air Pollution and Incidence of Cerebrovascular Events

    DEFF Research Database (Denmark)

    Stafoggia, Massimo; Cesaroni, Giulia; Peters, Annette

    2014-01-01

    BACKGROUND: Few studies have investigated effects of air pollution on the incidence of cerebrovascular events. OBJECTIVES: We assessed the association between long-term exposure to multiple air pollutants and the incidence of stroke in European cohorts. METHODS: Data from 11 cohorts were collected...... and occurrence of a first stroke was evaluated. Individual air pollution exposures were predicted from land-use regression models developed within the "European Study of Cohorts for Air Pollution Effects" (ESCAPE). The exposures were: PM2.5 (particulate matter [PM] below 2.5 µm in diameter), coarse PM (PM...... found suggestive evidence of an association between fine particles and incidence of cerebrovascular events in Europe, even at lower concentrations than set by the current air quality limit value....

  14. Long-Term Exposure to Low-Level Arsenic in Drinking Water and Diabetes Incidence

    DEFF Research Database (Denmark)

    Bräuner, Elvira V; Nordsborg, Rikke B; Andersen, Zorana Jovanovic

    2014-01-01

    BACKGROUND: Established causes of diabetes do not fully explain the epidemic. High level arsenic exposure has been implicated in diabetes risk but the effect of low-level arsenic exposure in drinking water remains unclear. OBJECTIVE: To determine if long-term exposure to low-level arsenic...... in drinking water in Denmark is associated with increased risk of diabetes using a large prospective cohort. METHODS: During 1993-1997 we recruited 57,053 persons. We followed each cohort member for diabetes occurrence from enrollment until 31 December 2006. We traced and geocoded residential addresses......, and 3,035 (5.8%) cases of diabetes based on a stricter definition. The adjusted incidence rate ratio's per 1 µg/L increment in arsenic levels in drinking water were (IRR = 1.03; 95% CI: 1.01, 1.06) and (IRR = 1.02; 95% CI: 0.99, 1.05) for all and strict diabetes cases, respectively. CONCLUSIONS: Long...

  15. Long-term differential changes in mouse intestinal metabolomics after γ and heavy ion radiation exposure.

    Directory of Open Access Journals (Sweden)

    Amrita K Cheema

    Full Text Available Tissue consequences of radiation exposure are dependent on radiation quality and high linear energy transfer (high-LET radiation, such as heavy ions in space is known to deposit higher energy in tissues and cause greater damage than low-LET γ radiation. While radiation exposure has been linked to intestinal pathologies, there are very few studies on long-term effects of radiation, fewer involved a therapeutically relevant γ radiation dose, and none explored persistent tissue metabolomic alterations after heavy ion space radiation exposure. Using a metabolomics approach, we report long-term metabolomic markers of radiation injury and perturbation of signaling pathways linked to metabolic alterations in mice after heavy ion or γ radiation exposure. Intestinal tissues (C57BL/6J, female, 6 to 8 wks were analyzed using ultra performance liquid chromatography coupled with electrospray quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS two months after 2 Gy γ radiation and results were compared to an equitoxic ⁵⁶Fe (1.6 Gy radiation dose. The biological relevance of the metabolites was determined using Ingenuity Pathway Analysis, immunoblots, and immunohistochemistry. Metabolic profile analysis showed radiation-type-dependent spatial separation of the groups. Decreased adenine and guanosine and increased inosine and uridine suggested perturbed nucleotide metabolism. While both the radiation types affected amino acid metabolism, the ⁵⁶Fe radiation preferentially altered dipeptide metabolism. Furthermore, ⁵⁶Fe radiation caused upregulation of 'prostanoid biosynthesis' and 'eicosanoid signaling', which are interlinked events related to cellular inflammation and have implications for nutrient absorption and inflammatory bowel disease during space missions and after radiotherapy. In conclusion, our data showed for the first time that metabolomics can not only be used to distinguish between heavy ion and γ radiation exposures, but

  16. Immune status of the nuclear plant workers in the long-term period after occupational exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kirillova, E.N.; Drugova, E.D.; Rybkina, V.L.; Muksinova, K.N. [Southern Ural Biophysic Institute, Ozyorsk (Russian Federation)

    2006-07-01

    Long-term clinical and epidemiological studies carried out in Russia have revealed a reliable linkage of onco-pathology with radiation exposure to the personnel of 'Mayak' Production Association (PA). At present most of the 'Mayak' veterans exposed to radiation during the first years of professional activity and accidents have reached the age of manifestation deleterious effects f chronic radiation exposure, including malignant neoplasms. According to the data published in a number of papers, immune and natural leukocyte resistance abnormalities have been observing for a long time after occupational exposure in doses significantly exceeding the limiting dose (dose limit DL). Long term studies were performed using large experimental material, we demonstrated stable immune abnormalities in animals of different species in the late period after exposure to high doses of chronic radiation. Incomplete recovery was revealed predominantly in T-system and also in the compartment of poly-potent and committed lymphatic precursors. The observed abnormalities, caused by residual radiation damage of blood-forming and immune systems, can be realized both directly and indirectly via formation of deterministic and/or somato-stochastic radiation effects. In this connection, studying of dependence of the frequency and character of immune abnormalities on the exposure level will enable to provide prediction of long-term consequences of chronic radiation, develop a survey program to form groups of risk of immunological deficiency, and design a scheme of timely prophylaxis and treatment techniques. The aim of present study was assessment of the immune status in the nuclear enterprise workers in the long-term period after occupational exposure and determination of dependence of the frequency of immune abnormalities on the accumulated radiation dose. The sample groups studied were form mainly of currently retired 'Mayak' workers, whose occupational activity

  17. Long-term exposure to gaseous air pollutants and cardio-respiratory mortality in Brisbane, Australia

    Directory of Open Access Journals (Sweden)

    Xiao Yu Wang

    2009-05-01

    Full Text Available This study examines the association of long-term exposure to gaseous air pollution with cardio-respiratory mortality in Brisbane, Australia, in the period 1996-2004. The pollutant concentrations were estimated using geographical information system (GIS techniques at the statistical local area (SLA level. The generalized estimating equations model was used to investigate the impact of nitrogen dioxide (NO2, ozone (O3 and sulphur dioxide (SO2 on mortality due to cardio-respiratory disease after adjusting for a range of potential confounders. An increase of 4.7% (95% confidence interval = 0.7-8.9% in cardio-respiratory mortality for 1 part per billion (ppb increment in annual average concentration of SO2 was estimated. However, there was no significant association between long-term exposures to NO2 or O3 and death due to cardio-respiratory disease. The results indicate that the annual average concentration of SO2 is associated with cardio-respiratory mortality at the SLA level and this association appears to vary with the geographical area.

  18. Behaviour of damselfly larvae (Enallagma cyathigerum) (Insecta, Odonata) after long-term exposure to PFOS

    Energy Technology Data Exchange (ETDEWEB)

    Gossum, Hans van [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: hans.vangossum@ua.ac.be; Bots, Jessica [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: jessica.bots@ua.ac.be; Snijkers, Tom [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: tom.snijkers@gmail.com; Meyer, Johan [Research group of Ecophysiology, Biochemistry and Toxicology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: izak.meyer@ua.ac.be; Van Wassenbergh, Sam [Laboratory for Functional Morphology, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp (Belgium)], E-mail: sam.vanwassenbergh@ua.ac.be; De Coen, Wim [Research group of Ecophysiology, Biochemistry and Toxicology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: wim.decoen@ua.ac.be; De Bruyn, Luc [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels (Belgium)], E-mail: luc.debruyn@ua.ac.be

    2009-04-15

    Perfluorooctane sulfonic acid (PFOS) is a persistent and ubiquitous environmental contaminant that has been detected in organisms worldwide. Here, we evaluate whether long-term (1 and 4 months) exposure to PFOS contamination affects the behavioural performance of freshwater larvae of the damselfly Enallagma cyathigerum (Insecta: Odonata). Our results show reduced behavioural performance with increasing PFOS concentration. In 1 month exposed larvae, no observed effect concentrations (NOECs) were 100 {mu}g/L for general activity. In 4 months exposed larvae, NOECs were 10 {mu}g/L, for each behavioural trait, except swimming acceleration of male larvae where the NOEC was 100 {mu}g/L. When faced with PFOS concentrations above the NOEC, E. cyathigerum larvae were less active, less capable to escape a simulated predator attack and less efficient in foraging. Together, our results show that damselfly larvae suffer reduced survival-related behavioural performance. - Long-term laboratory exposure to perfluorooctane sulfonic acid decreases behavioural performance of damselfly larvae (Insecta: Odonata)

  19. Exposure to disturbing noise and risk of long-term sickness absence among office workers:

    DEFF Research Database (Denmark)

    Clausen, Thomas; Kristiansen, Jesper; Vinsløv Hansen, Jørgen

    2013-01-01

    Purpose To investigate the association between selfreported exposure to disturbing noise and risk of long-term sickness absence (LTSA) for more than two consecutive weeks among office workers. Methods LTSA was measured using register data that were linked to survey data from 2,883 office workers...... aged 18–59 who were surveyed in 2005 on exposure to disturbing noise. The risk of LTSA was investigated using Cox proportional hazards model. Results Of the study population, 4.4 % had LTSA in the 1-year follow-up period. Compared to office workers who were ‘rarely or never’ exposed to disturbing noise...... at work, office workers who reported being ‘frequently’ exposed to disturbing noise had a significantly increased estimated risk of LTSA when adjusting for age, gender, smoking status, and managerial position (HR = 1.90; 95 % CI, 1.12–3.22). After additional adjustment for psychosocial work conditions...

  20. Microstructural degradation of boiler tube steels under long term exposure to high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Salonen, J.; Auerkari, P. [VTT Manufacturing Technology, Espoo (Finland)

    1996-12-31

    Thermal microstructural degradation was investigated by isothermal annealing of samples from boiler tube steels St 35.8, 15 Mo 3, 13 CrMo 44, 10 CrMo 9 10 and X20 CrMoV 12 1 in the temperature range 600-780 deg C for up to 2 000 h. Optical and scanning electron microscopy and hardness testing were used for characterising the micro structural changes and their time-temperature dependence. The results suggest a simple and consistent time-temperature dependence for all investigated materials, expected to apply also to long term service beyond the annealing time range of the present work. This would allow assessment of the in-service thermal exposure from the observed microstructure. A collection of micro graphs has been prepared for this purpose, to aid in classifying and evaluating the observed microstructural state in terms of isothermal exposure to high temperature. (orig.) (6 refs.)

  1. Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

    Science.gov (United States)

    Nevalainen, Liisa; Rantala, Marttiina V.; Luoto, Tomi P.; Ojala, Antti E. K.; Rautio, Milla

    2016-07-01

    Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective pigmentation throughout the past centuries, elucidate the adaptive responses of zooplankton to long-term variations in UV exposure, and estimate the potential of fossil zooplankton pigments in reconstructing aquatic UV regimes. The spectroscopic absorbance measurements of fossil Daphnia ephippia under UV (280-400 nm) and visible light (400-700 nm) spectral ranges indicated that melanin (absorbance maxima at UV wavebands 280-350 nm) and carotenoids (absorbance maxima at 400-450 nm) pigments were preserved in the ephippia in both sediment cores. Downcore measurements of the most important UV-protective pigment melanin (absorbance measured at 305 and 340 nm) showed marked long-term variations in the degree of melanisation. These variations likely represented long-term trends in aquatic UV exposure and were positively related with solar radiation intensity. The corresponding trends in melanisation and solar activity were disrupted at the turn of the 20th century in R1, but remained as strong in Fugledammen. The reversed trends in the R1 core were simultaneous with a significant aquatic community reorganization taking place in the lake, suggesting that recent environmental changes, likely related to climate warming had a local effect on pigmentation strategies. This time horizon is also

  2. Impact of Long-term Exposure to Air Particulate Matter on Life Expectancy and Survival Rate of Shanghai Residents

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To evaluate the impact of long-term air particulate matter exposure on the life expectancy and survival rate of Shanghai residents. Methods Epidemiology - based exposureresponse function was used for the calculation of attributable deaths to air particulate matter in Shanghai, and the effect of long-term exposure to particulate matter on life expectancy and survival rate was estimated using the life table of Shanghai residents in 1999. Results It was shown that in 1999, the long-term air particulate matter exposure caused 1.34-1.69 years reduction of life expectancy and a decrease of survival rate for each age group of Shanghai residents. Conclusion The effect of long-term exposure to air particulate matter on life expectancy is substantial in Shanghai.

  3. Hedging Long-Term Exposures of a Well-Diversified Portfolio with Short-Term Stock Index Futures Contracts

    National Research Council Canada - National Science Library

    Liu, Yufang; Zhang, Wei-Guo; Chen, Rongda; Fu, Junhui

    2014-01-01

      It is difficult for passive portfolio strategy to manage the long-term exposure of a well-diversified portfolio because stock index futures contracts have a finite life limited by their maturity...

  4. Effects of long-term electromagnetic field exposure on spatial learning and memory in rats.

    Science.gov (United States)

    Hao, Dongmei; Yang, Lei; Chen, Su; Tong, Jun; Tian, Yonghao; Su, Benhang; Wu, Shuicai; Zeng, Yanjun

    2013-02-01

    With the development of communications industry, mobile phone plays an important role in daily life. Whether or not the electromagnetic radiation emitted by mobile phone causes any adverse effects on brain function has become of a great concern. This paper investigated the effect of electromagnetic field on spatial learning and memory in rats. 32 trained Wistar rats were divided into two groups: exposure group and control group. The exposure group was exposed to 916 MHz, 10w/m2 mobile phone electromagnetic field (EMF) 6 h a day, 5 days a week, 10 weeks. The completion time, number of total errors and the neuron discharge signals were recorded while the rats were searching for food in an eight-arm radial maze at every weekend. The neuron signals of one exposed rat and one control rat in the maze were obtained by the implanted microelectrode arrays in their hippocampal regions. It can be seen that during the weeks 4-5 of the experiment, the average completion time and error rate of the exposure group were longer and larger than that of control group (p exposure, and the rats can adapt to long-term EMF exposure.

  5. Long-term exposure to incense smoke alters metabolism in Wistar albino rats.

    Science.gov (United States)

    Alokail, Majed S; Al-Daghri, Nasser M; Alarifi, Saud A; Draz, Hossam M; Hussain, Tajamul; Yakout, Sobhy M

    2011-03-01

    The burning of incense is an important source of indoor air pollution in Asia. We assessed the effect of long-term exposure to incense smoke on the body weight and levels of circulating glucose, triglycerides, total cholesterol, HDL-cholesterol, insulin, adiponectin and leptin in Wistar albino rats. Two groups of rats were used. First group (n = 12) was exposed daily to incense smoke for 4 months at the rate of 4 g day(-1) in the exposure chamber. Another group of rats (n = 12), was used as non-exposed control. Blood samples were collected from all animals after 4, 8, 12 and 16 weeks of exposure. Serum glucose, triglycerides, total cholesterol and HDL-cholesterol, LDL-cholesterol insulin, adiponectin and leptin were measured. Our results showed that incense smoke exposure was associated with decreased weight gain and the adverse metabolic changes of increased triglycerides and decreased HDL-cholesterol concentrations. Exposure to incense was also associated with a transient increase of leptin levels. Taken together, these data suggest that incense smoke influences metabolism adversely in rats. The effect of incense smoke on human health and the underlying mechanisms need to be studied further.

  6. Exposure of mouse to high gravitation forces induces long-term potentiation in the hippocampus.

    Directory of Open Access Journals (Sweden)

    Ishii M

    2004-06-01

    Full Text Available The central nervous system is highly plastic and has been shown to undergo both transient and chronic adaptive changes in response to environmental influences. The purpose of this study was to investigate the effect of hypergravic field on long-term potentiation (LTP in the mouse hippocampus. Exposure of mice to 4G fields for 48 h had no effect on input-output coupling during extracellular stimulation of Schaffer collaterals and paired pulse facilitation, suggesting that the hypergravic exposure had no detrimental effect on basal neurotransmission in the hippocampus. However, the exposure to 4G fields for 48 h significantly induced LTP compared with the control mouse hippocampus. In contrast, no significant changes of late-phase LTP (L-LTP were found in the hippocampi of mice exposed to the hypergravic field. Exposure of mice to 4G fields for 48 h enhanced AMPA receptor phosphorylation but not cyclic AMP-responsive element binding protein (CREB phosphorylation. These results suggest that exposure to hyperdynamic fields influences the synaptic plasticity in the hippocampus.

  7. Abiotic dechlorination in rock matrices impacted by long-term exposure to TCE.

    Science.gov (United States)

    Schaefer, Charles E; Towne, Rachael M; Lippincott, David R; Lacombe, Pierre J; Bishop, Michael E; Dong, Hailiang

    2015-01-01

    Field and laboratory tests were performed to evaluate the abiotic reaction of trichloroethene (TCE) in sedimentary rock matrices. Hydraulically conductive fractures, and the rock directly adjacent to the hydraulically conductive fractures, within a historically contaminated TCE bedrock aquifer were used as the basis for this study. These results were compared to previous work using rock that had not been exposed to TCE (Schaefer et al., 2013) to assess the impact of long-term TCE exposure on the abiotic dechlorination reaction, as the longevity of these reactions after long-term exposure to TCE was hitherto unknown. Results showed that potential abiotic TCE degradation products, including ethane, ethene, and acetylene, were present in the conductive fractures. Using minimally disturbed slices of rock core at and near the fracture faces, laboratory testing on the rocks confirmed that abiotic dechlorination reactions between the rock matrix and TCE were occurring. Abiotic daughter products measured in the laboratory under controlled conditions were consistent with those measured in the conductive fractures, except that propane also was observed as a daughter product. TCE degradation measured in the laboratory was well described by a first order rate constant through the 118-d study. Observed bulk first-order TCE degradation rate constants within the rock matrix were 1.3×10(-8) s(-1). These results clearly show that abiotic dechlorination of TCE is occurring within the rock matrix, despite decades of exposure to TCE. Furthermore, these observed rates of TCE dechlorination are expected to have a substantial impact on TCE migration and uptake/release from rock matrices.

  8. Long-term Effects of Multiple Glucocorticoid Exposures in Neonatal Mice

    Directory of Open Access Journals (Sweden)

    Susan E. Maloney

    2011-12-01

    Full Text Available Glucocorticoids (GCs such as dexamethasone (DEX or betamethasone are repeatedly administered for up to a month to prematurely born infants as a treatment for chronic lung dysfunction. Results of clinical trials have shown that the use of GCs in these infants induces long-term deficits in neuromotor function and cognition. We have previously shown that a single exposure to clinically relevant doses of DEX or other GCs in the mouse during a period corresponding to the human perinatal period produces a dramatic increase in apoptotic cell death of neural progenitor cells in the developing cerebellum. To provide a model approximating more chronic clinical dosing regimens, we evaluated possible behavioral effects resulting from repeated exposures to DEX and subsequent GC-induced neuronal loss where neonatal mouse pups were injected with 3.0 mg/kg DEX or saline on postnatal days 7, 9, and 11 (DEX3 treatment. Adult, DEX3-treated mice exhibited long-term, possibly permanent, neuromotor deficits on a complex activity wheel task, which requires higher-order motor co-ordination skills. DEX3 mice exhibited impaired performance on this task relative to saline controls in each of two independent studies involving separate cohorts of mice. Histopathology studies utilizing stereological neuronal counts conducted in behaviorally-tested mice showed that the DEX3 treatment resulted in a significant decrease in the number of neurons in the internal granule layer (IGL of the cerebellum, although the number of neurons in the Purkinje cell layer were unchanged. The results suggest that multiple neonatal DEX exposures can produce chronic deficits in fine motor co-ordination that are associated with cerebellar IGL neuronal loss.

  9. UV exposure modulates hemidesmosome plasticity, contributing to long-term pigmentation in human skin

    Science.gov (United States)

    Coelho, Sergio G.; Valencia, Julio C.; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Miller, Sharon A.; Beer, Janusz Z.; Zhang, Guofeng; Tuma, Pamela L.; Hearing, Vincent J.

    2014-01-01

    Human skin color, i.e. pigmentation, differs widely among individuals as do their responses to various types of ultraviolet radiation (UV) and their risks of skin cancer. In some individuals UV-induced pigmentation persists for months to years in a phenomenon termed long-lasting pigmentation (LLP). It is unclear whether LLP is an indicator of potential risk for skin cancer. LLP seems to have similar features to other forms of hyperpigmentation, e.g. solar lentigines or age spots, which are clinical markers of photodamage and risk factors for precancerous lesions. To investigate what UV-induced molecular changes may persist in individuals with LLP, clinical specimens from non-sunburn-inducing repeated UV exposures (UVA, UVB or UVA+UVB) at 4 months post-exposure (short-term LLP) were evaluated by microarray analysis and dataset mining. Validated targets were further evaluated in clinical specimens from 6 healthy individuals (3 LLP+ and 3 LLP-) followed for more than 9 months (long-term LLP) who initially received a single sunburn-inducing UVA+UVB exposure. The results support a UV-induced hyperpigmentation model in which basal keratinocytes have an impaired ability to remove melanin that leads to a compensatory mechanism by neighboring keratinocytes with increased proliferative capacity to maintain skin homeostasis. The attenuated expression of SOX7 and other hemidesmosomal components (integrin α6β4 and plectin) leads to increased melanosome uptake by keratinocytes and points to a spatial regulation within the epidermis. The reduced density of hemidesmosomes provides supporting evidence for plasticity at the epidermal-dermal junction. Altered hemidesmosome plasticity, and the sustained nature of LLP, may be mediated by the role of SOX7 in basal keratinocytes. The long-term sustained subtle changes detected are modest, but sufficient to create dramatic visual differences in skin color. These results suggest that the hyperpigmentation phenomenon leading to increased

  10. Early exposure to volatile anesthetics impairs long-term associative learning and recognition memory.

    Directory of Open Access Journals (Sweden)

    Bradley H Lee

    Full Text Available BACKGROUND: Anesthetic exposure early in life affects neural development and long-term cognitive function, but our understanding of the types of memory that are altered is incomplete. Specific cognitive tests in rodents that isolate different memory processes provide a useful approach for gaining insight into this issue. METHODS: Postnatal day 7 (P7 rats were exposed to either desflurane or isoflurane at 1 Minimum Alveolar Concentration for 4 h. Acute neuronal death was assessed 12 h later in the thalamus, CA1-3 regions of hippocampus, and dentate gyrus. In separate behavioral experiments, beginning at P48, subjects were evaluated in a series of object recognition tests relying on associative learning, as well as social recognition. RESULTS: Exposure to either anesthetic led to a significant increase in neuroapoptosis in each brain region. The extent of neuronal death did not differ between groups. Subjects were unaffected in simple tasks of novel object and object-location recognition. However, anesthetized animals from both groups were impaired in allocentric object-location memory and a more complex task requiring subjects to associate an object with its location and contextual setting. Isoflurane exposure led to additional impairment in object-context association and social memory. CONCLUSION: Isoflurane and desflurane exposure during development result in deficits in tasks relying on associative learning and recognition memory. Isoflurane may potentially cause worse impairment than desflurane.

  11. Neonatal exposure to novelty enhances long-term potentiation in CA1 of the rat hippocampus.

    Science.gov (United States)

    Tang, Akaysha C; Zou, Bende

    2002-01-01

    Exposing rats to an enriched environment over an extended period of time has been shown to enhance hippocampal long-term potentiation (LTP). Whether such prolonged exposure to environmental manipulation is necessary for LTP enhancement and whether the environmentally induced enhancement can persist long after the cessation of the environmental manipulation remain unknown. Using a novelty exposure procedure modified from the method of neonatal handling, we exposed neonatal rats to a non-home environment for 3 min/day during the first 3 weeks of life. We examined the LTP of both population spikes and excitatory postsynaptic potentials (EPSPs), in vitro, in the CA1 of the hippocampus during adulthood (7-8 and 13-14 months of age). We found that both the LTP of population spikes and the LTP of EPSPs were enhanced among animals who experienced neonatal novelty exposure. These results demonstrate that effective environmental enhancement of LTP can be achieved by as brief and as transient a manipulation as a 3-min/day exposure over the first 3 weeks of life. The resulting enhancement can outlast the environmental manipulation by at least 1 year.

  12. Cognitive impairment in rats after long-term exposure to GSM-900 mobile phone radiation.

    Science.gov (United States)

    Nittby, Henrietta; Grafström, Gustav; Tian, Dong Ping; Malmgren, Lars; Brun, Arne; Persson, Bertil R R; Salford, Leif G; Eberhardt, Jacob

    2008-04-01

    Considering the frequent use of mobile phones, we have directed attention to possible implications on cognitive functions. In this study we investigated in a rat model the long-term effects of protracted exposure to Global System for Mobile Communication-900 MHz (GSM-900) radiation. Out of a total of 56 rats, 32 were exposed for 2 h each week for 55 weeks to radio-frequency electromagnetic radiation at different SAR levels (0.6 and 60 mW/kg at the initiation of the experimental period) emitted by a (GSM-900) test phone. Sixteen animals were sham exposed and eight animals were cage controls, which never left the animal house. After this protracted exposure, GSM-900 exposed rats were compared to sham exposed controls. Effects on exploratory behaviour were evaluated in the open-field test, in which no difference was seen. Effects on cognitive functions were evaluated in the episodic-like memory test. In our study, GSM exposed rats had impaired memory for objects and their temporal order of presentation, compared to sham exposed controls (P = 0.02). Detecting the place in which an object was presented was not affected by GSM exposure. Our results suggest significantly reduced memory functions in rats after GSM microwave exposure (P = 0.02).

  13. Microstructure Stability of Inconel 740H Alloy After Long Term Exposure at 750℃

    Directory of Open Access Journals (Sweden)

    DANG Ying-ying

    2016-09-01

    Full Text Available Unstressed exposure tests of Inconel 740H alloy tube were carried out at 750℃ for 500-3000h. The microstructure evolution and microhardness were studied by means of thermodynamic simulation, OM, FEG-SEM and microhardness testing. The results show that the tube is qualified if both chemical composition and tensile properties of the as-received alloy meet the corresponding requirements of ASME. After long term exposure, the main precipitates are γ' and M23C6, and no η and σ phase. With the prolonging of exposure time, the coarsening of γ' becomes faster and the law of relationship between the radius of γ' and time accords with LSW Ostwald ripening law; meanwhile, the change in size of M23C6 is not so obvious. During the whole process, microhardness increases firstly and then decreases, but the fluctuation is slight. The changes of microstructure and hardness indicate that, after long time exposure, the domestic Inconel 740H has good stability and can be used for further carrying out the investigation on the mechanical property of creep-rupture.

  14. Long-term electromagnetic exposure of developing neuronal networks: A flexible experimental setup.

    Science.gov (United States)

    Oster, Stefan; Daus, Andreas W; Erbes, Christian; Goldhammer, Michael; Bochtler, Ulrich; Thielemann, Christiane

    2016-05-01

    Neuronal networks in vitro are considered one of the most promising targets of research to assess potential electromagnetic field induced effects on neuronal functionality. A few exposure studies revealed there is currently no evidence of any adverse health effects caused by weak electromagnetic fields. Nevertheless, some published results are inconsistent. Particularly, doubts have been raised regarding possible athermal biological effects in the young brain during neuronal development. Therefore, we developed and characterized a flexible experimental setup based on a transverse electromagnetic waveguide, allowing controlled, reproducible exposure of developing neuronal networks in vitro. Measurement of S-parameters confirmed very good performance of the Stripline in the band of 800-1000 MHz. Simulations suggested a flexible positioning of cell culture dishes throughout a large exposure area, as specific absorption rate values were quite independent of their position (361.7 ± 11.4 mW/kg) at 1 W, 900 MHz. During exposure, thermal drift inside cellular medium did not exceed 0.1 K. Embryonic rat cortical neurons were cultivated on microelectrode array chips to non-invasively assess electrophysiological properties of electrogenic networks. Measurements were taken for several weeks, which attest to the experimental setup being a reliable system for long-term studies on developing neuronal tissue.

  15. Stevioside counteracts the alpha-cell hypersecretion caused by long-term palmitate exposure

    DEFF Research Database (Denmark)

    Hong, J; Chen, L; Jeppesen, P B;

    2006-01-01

    Long-term exposure to fatty acids impairs beta-cell function in type 2 diabetes, but little is known about the chronic effects of fatty acids on alpha-cells. We therefore studied the prolonged impact of palmitate on alpha-cell function and on the expression of genes related to fuel metabolism. We......-activated receptor-gamma, and stearoyl-CoA desaturase gene expressions in the presence of palmitate (Pacids leads to a hypersecretion of glucagon and an accumulation of TG content in clonal alpha-TC1-6 cells. Stevioside was able to counteract the alpha......-cell hypersecretion caused by palmitate and enhanced the expression of genes involved in fatty acid metabolism. This indicates that stevioside may be a promising antidiabetic agent in treatment of type 2 diabetes....

  16. Long-term exposure of mice to nucleoside analogues disrupts mitochondrial DNA maintenance in cortical neurons.

    Directory of Open Access Journals (Sweden)

    Yulin Zhang

    Full Text Available Nucleoside analogue reverse transcriptase inhibitor (NRTI, an integral component of highly active antiretroviral therapy (HAART, was widely used to inhibit HIV replication. Long-term exposure to NRTIs can result in mitochondrial toxicity which manifests as lipoatrophy, lactic acidosis, cardiomyopathy and myopathy, as well as polyneuropathy. But the cerebral neurotoxicity of NRTIs is still not well known partly due to the restriction of blood-brain barrier (BBB and the complex microenvironment of the central nervous system (CNS. In this study, the Balb/c mice were administered 50 mg/kg stavudine (D4T, 100 mg/kg zidovudine (AZT, 50 mg/kg lamivudine (3TC or 50 mg/kg didanosine (DDI per day by intraperitoneal injection, five days per week for one or four months, and primary cortical neurons were cultured and exposed to 25 µM D4T, 50 µM AZT, 25 µM 3TC or 25 µM DDI for seven days. Then, single neuron was captured from mouse cerebral cortical tissues by laser capture microdissection. Mitochondrial DNA (mtDNA levels of the primary cultured cortical neurons, and captured neurons or glial cells, and the tissues of brains and livers and muscles were analyzed by relative quantitative real-time PCR. The data showed that mtDNA did not lose in both NRTIs exposed cultured neurons and one month NRTIs treated mouse brains. In four months NRTIs treated mice, brain mtDNA levels remained unchanged even if the mtDNA levels of liver (except for 3TC and muscle significantly decreased. However, mtDNA deletion was significantly higher in the captured neurons from mtDNA unchanged brains. These results suggest that long-term exposure to NRTIs can result in mtDNA deletion in mouse cortical neurons.

  17. Anastrozole versus tamoxifen as adjuvant therapy for Japanese postmenopausal patients with hormone-responsive breast cancer: efficacy results of long-term follow-up data from the N-SAS BC 03 trial.

    Science.gov (United States)

    Aihara, Tomohiko; Yokota, Isao; Hozumi, Yasuo; Aogi, Kenjiro; Iwata, Hiroji; Tamura, Motoshi; Fukuuchi, Atsushi; Makino, Haruhiko; Kim, Ryungsa; Andoh, Masashi; Tsugawa, Koichiro; Ohno, Shinji; Yamaguchi, Takuhiro; Ohashi, Yasuo; Watanabe, Toru; Takatsuka, Yuichi; Mukai, Hirofumi

    2014-11-01

    Aromatase inhibitors are superior to tamoxifen as adjuvant therapy in postmenopausal patients with hormone-responsive breast cancer. We report the follow-up efficacy results from the N-SAS BC 03 trial (UMIN CTRID: C000000056) where anastrozole was compared with tamoxifen as adjuvant therapy in postmenopausal Japanese patients with hormone-responsive early breast cancer. The full analysis set contained 696 patients (anastrozole arm, n = 345; tamoxifen arm, n = 351). The log-rank test was used to compare the two groups in terms of disease-free survival (DFS) and relapse-free survival (RFS); Kaplan-Meier estimates were calculated. The treatment effects were estimated by Cox's proportional hazards model. To examine time-varying effect of hazard ratios, we estimated time-varying hazard ratios at time t [HR(t)] using data from time t up to 12 months. After a median follow-up of 98.5 months, hazard ratios (95% CIs) were 0.90 (0.65-1.24; log-rank p = 0.526) for DFS and 0.83 (0.56-1.23; log-rank p = 0.344) for RFS. Hazard ratios (95% CIs) for DFS and RFS up to 36 months were 0.69 (0.40-1.17) and 0.54 (0.27-1.06) and those after 36 months were 1.06 (0.70-1.59) and 1.05 (0.64-1.73), respectively. Time-varying hazard ratios for both DFS and RFS showed that hazard ratios were initially in favor of anastrozole and approached 1.0 at around 36 months. Superior efficacy of anastrozole to tamoxifen suggested by the initial analysis was not confirmed in the present analysis after a long-term follow-up period. Advantage of anastrozole was the greatest immediately after switching from tamoxifen and then decreased thereafter.

  18. Self-reported noise exposure as a risk factor for long-term sickness absence

    DEFF Research Database (Denmark)

    Clausen, Thomas; Christensen, Karl Bang; Lund, Thomas;

    2009-01-01

    -quarter and three-quarters of their time at work had an increased risk of 43% (CI: 10-85%) for sickness absence of two weeks or longer compared to men that reported never to be exposed to loud noise. Men that reported to be little/rarely exposed to loud noise had an increased risk of 37% (CI: 7-76%). Men...... that reported to be exposed to loud noise more than three-quarters of their time at work did not have an increased risk of sickness absence. This latter result might be due a healthy worker effect and/or more frequent use of hearing protection in this group. Along with evidence from previous studies......Self-reported noise exposure is on the rise in Denmark. Little is known, however, about the social consequences, including sickness absence, of noise exposure. The aim of this paper was to investigate the association between self-reported noise exposure and long-term sickness absence...

  19. Adaptations of the vestibular system to short and long-term exposures to altered gravity

    Science.gov (United States)

    Bruce, L.

    Long-term space flight creates unique environmental conditions to which the vestibular system must adapt for optimal survival. We are studying two aspects of this vestibular adaptation: (1) How does long-term exposure to microgravity and hypergravity affect the development of vestibular afferents? (2) How does short- term exposure to extremely rapid changes in gravity, such as those that occur during launch and landing, affect the vestibular system. During space flight the gravistatic receptors in the otolith organs are effectively unloaded. In hypergravity conditions they are overloaded. However, the angular acceleration receptors of the semicircular canals receive relatively normal stimulation in both micro- and hypergravity.Rat embryos exposed to microgravity from gestation day 10 (prior to vestibular function) until gestation day 20 (vestibular system is somewhat functional) showed that afferents from the posterior vertical canal projecting to the medial vestibular nucleus developed similarly in microgravity, hypergravity, and in controls . However, afferents from the saccule showed delayed development in microgravity as compared to development in hypergravity and in controls. Cerebellar plasticity is crucial for modification of sensory-motor control and learning. Thus we explored the possibility that strong vestibular stimuli would modify cerebellar motor control (i.e., eye movement, postural control, gut motility) by altering the morphology of cerebellar Purkinje cells. To study the effects of short-term exposures to strong vestibular stimuli we focused on structural changes in the vestibulo-cerebellum that are caused by strong vestibular stimuli. Adult mice were exposed to various combinations of constant and/or rapidly changing angular and linear accelerations for 8.5 min (the time length of shuttle launch). Our data shows that these stimuli cause intense excitation of cerebellar Purkinje cells, inducing up-regulation of clathrin-mediated endocytosis

  20. Long-term exposure to residential traffic noise and changes in body weight and waist circumference

    DEFF Research Database (Denmark)

    Christensen, Jeppe S; Raaschou-Nielsen, Ole; Tjønneland, Anne

    2015-01-01

    exposure to traffic noise was calculated for all participants' present and historical addresses using the Nordic prediction method. The associations between traffic noise and changes in adiposity measures after a mean follow-up of 5.3 years were analyzed by linear and logistic regression with adjustments...... circumference. For example, time-weighted mean exposure 5-years preceding follow-up was associated with a yearly weight gain of 15.4g (95% confidence interval (CI): 2.14; 28.7) and a yearly increase in waist circumference of 0.22mm (95% CI: 0.018; 0.43) per 10dB. Similarly, in Poisson regression models we found......: We aimed to investigate the association between long-term residential traffic noise and changes in adiposity. MATERIALS AND METHODS: The study was based on 39,720 middle-aged Danish men and women from a cohort, with information on weight and waist circumference at two points in time. Residential...

  1. Assessment of Effects of the Long-Term Exposure of Agricultural Crops to Carbon Nanotubes.

    Science.gov (United States)

    Lahiani, Mohamed H; Nima, Zeid A; Villagarcia, Hector; Biris, Alexandru S; Khodakovskaya, Mariya V

    2017-09-06

    Carbon-based nanoparticles (CBNs) are nanomaterials that have been shown to be plant growth regulators. Here, we investigated the effects of long-term exposure to multi-walled carbon nanotubes (MWCNTs) on the growth of three important crops (barley, soybean, and corn). The tested species were cultivated in hydroponics supplemented with 50 μg/mL MWCNTs. After 20 weeks of continuous exposure to the nanomaterials, no significant toxic effects on plant development were observed. Several positive phenotypical changes were recorded, in addition to the enhancement of photosynthesis in MWCNT-exposed crops. Raman spectroscopy with point-by-point mapping proved that the MWCNTs in the hydroponic solution moved into all tested species and were distributed in analyzed organs (leaves, stems, roots, and seeds). Our results confirmed the significant potential of CBN in plant agriculture. However, the documented presence of MWCNTs in different organs of all exposed crops highlighted the importance of detailed risk assessment of nanocontaminated plants moving into the food chain.

  2. Long-term noise exposure and the risk for type 2 diabetes: a meta-analysis.

    Science.gov (United States)

    Dzhambov, Angel Mario

    2015-01-01

    Diabetes mellitus is one of the leading causes for disability and mortality in modern societies. Apart from personal factors its incidence might be influenced by environmental risks such as air pollution and noise. This paper reports a systematic review and meta-analysis on the risk for type 2 diabetes due to long-term noise exposure. Electronic searches in MEDLINE, EMBASE and the Internet yielded 9 relevant studies (5 for residential and 4 for occupational exposure). They were checked against a predefined list of safeguards against bias producing individual quality scores, which were then fed to MetaXL to conduct a quality effects meta-analysis. People exposed at their homes to roughly L(den) > 60 dB had 22% higher risk (95% confidence interval [CI]: 1.09-1.37) for type 2 diabetes in comparison to those exposed to L(den) risk (95% CI: 1.05-1.35) for L(den) = 60-70 dB versus L(den) risk (relative risk [RR] = 0.91, 95% CI: 0.78-1.06) for 85 dB. There was no heterogeneity in the two groups (I² = 0.00). The results should be interpreted with caution due to methodological discrepancies across the studies; however, they are indicative of the close links that noise pollution might have not only to cardiovascular diseases but to endocrine dysfunction as well.

  3. Long-term noise exposure and the risk for type 2 diabetes: A meta-analysis

    Directory of Open Access Journals (Sweden)

    Angel Mario Dzhambov

    2015-01-01

    Full Text Available Diabetes mellitus is one of the leading causes for disability and mortality in modern societies. Apart from personal factors its incidence might be influenced by environmental risks such as air pollution and noise. This paper reports a systematic review and meta-analysis on the risk for type 2 diabetes due to long-term noise exposure. Electronic searches in MEDLINE, EMBASE and the Internet yielded 9 relevant studies (5 for residential and 4 for occupational exposure. They were checked against a predefined list of safeguards against bias producing individual quality scores, which were then fed to MetaXL to conduct a quality effects meta-analysis. People exposed at their homes to roughly L den > 60 dB had 22% higher risk (95% confidence interval [CI]: 1.09-1.37 for type 2 diabetes in comparison to those exposed to L den 85 dB. There was no heterogeneity in the two groups (I2 = 0.00. The results should be interpreted with caution due to methodological discrepancies across the studies; however, they are indicative of the close links that noise pollution might have not only to cardiovascular diseases but to endocrine dysfunction as well.

  4. Viability of barley seeds after long-term exposure to outer side of international space station

    Science.gov (United States)

    Sugimoto, Manabu; Ishii, Makoto; Mori, Izumi C.; Elena, Shagimardanova; Gusev, Oleg A.; Kihara, Makoto; Hoki, Takehiro; Sychev, Vladimir N.; Levinskikh, Margarita A.; Novikova, Natalia D.; Grigoriev, Anatoly I.

    2011-09-01

    Barley seeds were exposed to outer space for 13 months in a vented metal container without a climate control system to assess the risk of physiological and genetic mutation during long-term storage in space. The space-stored seeds (S0 generation), with an 82% germination rate in 50 seeds, lost about 20% of their weight after the exposure. The germinated seeds showed normal growth, heading, and ripening. The harvested seeds (S1 generation) also germinated and reproduced (S2 generation) as did the ground-stored seeds. The culm length, ear length, number of seed, grain weight, and fertility of the plants from the space-stored seeds were not significantly different from those of the ground-stored seeds in each of the S0 and S1 generation. Furthermore, the S1 and S2 space-stored seeds respectively showed similar β-glucan content to those of the ground-stored seeds. Amplified fragment length polymorphism analysis with 16 primer combinations showed no specific fragment that appears or disappears significantly in the DNA isolated from the barley grown from the space-stored seeds. Though these data are derived from nine S0 space-stored seeds in a single exposure experiment, the results demonstrate the preservation of barley seeds in outer space for 13 months without phenotypic or genotypic changes and with healthy and vigorous growth in space.

  5. Long-Term Flexural Behaviors of GFRP Reinforced Concrete Beams Exposed to Accelerated Aging Exposure Conditions

    Directory of Open Access Journals (Sweden)

    Yeonho Park

    2014-06-01

    Full Text Available This study investigates the impact of accelerated aging conditions on the long-term flexural behavior and ductility of reinforced concrete (RC members with glass fiber-reinforced polymer (GFRP bars (RC-GFRP specimen and steel bars (RC-steel specimen. A total of thirty six specimens were designed with different amounts of reinforcement with three types of reinforcing bars (i.e., helically wrapped GFRP, sand-coated surface GFRP and steel. Eighteen specimens were subjected to sustained loads and accelerated aging conditions (i.e., 47 °C and 80% relative humidity in a chamber. The flexural behavior of specimens under 300-day exposure was compared to that of the companion specimens without experiencing accelerated aging conditions. Results indicate that the accelerated aging conditions reduced flexural capacity in not only RC-steel, but also RC-GFRP specimens, with different rates of reduction. Different types of GFRP reinforcement exhibited different rates of degradation of the flexural capacity when embedded in concrete under the same exposure conditions. Several existing models were compared with experimental results for predicting the deflection and deformability index for specimens. Bischoff and Gross’s model exhibited an excellent prediction of the time-dependent deflections. Except for the deformability index proposed by Jaeger, there was no general trend related to the aging duration. This study recommends the need for further investigation on the prediction of the deformability index.

  6. Effects of long-term cold exposure on contractile muscles of rats.

    Science.gov (United States)

    Nomura, Takeshi; Kawano, Fuminori; Kang, Myung Sun; Lee, Jun Hak; Han, Eun Young; Kim, Chang Keun; Sato, Yuzo; Ohira, Yoshinobu

    2002-02-01

    The effects of 20-week cold exposure on contractile properties of soleus and extensor digitorum longus (EDL) muscles and plasma hormone levels were studied in rats. Twenty male Wistar rats (5 week old) were randomly divided into 2 groups (n = 10 each): cage-control and cold-exposed. The rats in the cold-exposed group were immersed in shoulder-deep water (approximately 18 degrees C) for 1 h/d, 5 d/week, for 20 weeks. The temperature and humidity of the animal room with 12:12 h light-dark cycle were maintained at approximately 23 degrees C and 55%, respectively. The rats were pair-fed powdered diets. The electromyogram activities in soleus and EDL were elevated by cold exposure. The body weight and absolute soleus wet weight of the cold-exposed group were significantly less than controls at the end of experiment. The one-half relaxation time and contraction time of EDL were significantly longer in the cold-exposed group than in the control group. The rate of twitch tension development, normalized by the maximum twitch tension, in EDL of the cold-exposed group was less than in the control group. Further, the fatigue resistance of EDL, but not of soleus, in response to train stimulation at 10 Hz was improved by cold exposure. The plasma levels of thyroid hormones, 3,5,3'-triiodothyronine and thyroxine, were significantly greater in cold-exposed group. Similar changes were also seen in the plasma catecholamine levels in the cold-exposed group (p > 0.05). It is suggested that long-term cold exposure causes a shift of the contractile properties of fast-twitch EDL muscle toward the slow-twitch type. The results also indicated that the characteristics of muscles responded more strongly to an increased activity level than to the elevation of plasma hormones.

  7. Nitrifying moving bed biofilm reactor (MBBR) biofilm and biomass response to long term exposure to 1 °C.

    Science.gov (United States)

    Hoang, V; Delatolla, R; Abujamel, T; Mottawea, W; Gadbois, A; Laflamme, E; Stintzi, A

    2014-02-01

    This study aims to investigate moving bed biofilm reactor (MBBR) nitrification rates, nitrifying biofilm morphology, biomass viability as well as bacterial community shifts during long-term exposure to 1 °C. Long-term exposure to 1 °C is the key operational condition for potential ammonia removal upgrade units to numerous northern region treatment systems. The average laboratory MBBR ammonia removal rate after long-term exposure to 1 °C was measured to be 18 ± 5.1% as compared to the average removal rate at 20 °C. Biofilm morphology and specifically the thickness along with biomass viability at various depths in the biofilm were investigated using variable pressure electron scanning microscope (VPSEM) imaging and confocal laser scanning microscope (CLSM) imaging in combination with viability live/dead staining. The biofilm thickness along with the number of viable cells showed significant increases after long-term exposure to 1 °C. Hence, this study observed nitrifying bacteria with higher activities at warm temperatures and a slightly greater quantity of nitrifying bacteria with lower activities at cold temperatures in nitrifying MBBR biofilms. Using DNA sequencing analysis, Nitrosomonas and Nitrosospira (ammonia oxidizers) as well as Nitrospira (nitrite oxidizer) were identified and no population shift was observed between 20 °C and after long-term exposure to 1 °C.

  8. Comparison of different exposute assessment methods to estimate the long-term dietary exposure to dioxins and ochratoxin A

    NARCIS (Netherlands)

    Boon, P.E.; Bonthuis, M.; Voet, van der H.; Klaveren, van J.D.

    2011-01-01

    Long-term exposures to dioxins (PCCD/F and dioxin-like PCBs) and ochratoxin A were calculated using food consumption data of the European concise database combined with concentration data of the Netherlands (NL) using a deterministic approach. To refine these assessments, exposures were also calcula

  9. Long-term personal exposure to traffic-related air pollution among school children, a validation study.

    NARCIS (Netherlands)

    Roosbroeck, Sofie van; Wichmann, Janine; Janssen, Nicole A H; Hoek, Gerard; Wijnen, Joop H van; Lebret, Erik; Brunekreef, Bert

    2006-01-01

    Several recent studies suggest an association between long-term exposure to traffic-related air pollution and health. Most studies use indicators of exposure such as outdoor air pollution or traffic density on the street of residence. Little information is available about the validity of these measu

  10. Long term, continuous exposure to panobinostat induces terminal differentiation and long term survival in the TH-MYCN neuroblastoma mouse model.

    Science.gov (United States)

    Waldeck, Kelly; Cullinane, Carleen; Ardley, Kerry; Shortt, Jake; Martin, Ben; Tothill, Richard W; Li, Jason; Johnstone, Ricky W; McArthur, Grant A; Hicks, Rodney J; Wood, Paul J

    2016-07-01

    Neuroblastoma is the most common extra-cranial malignancy in childhood and accounts for ∼15% of childhood cancer deaths. Amplification of MYCN in neuroblastoma is associated with aggressive disease and predicts for poor prognosis. Novel therapeutic approaches are therefore essential to improving patient outcomes in this setting. The histone deacetylases are known to interact with N-Myc and regulate numerous cellular processes via epigenetic modulation, including differentiation. In this study, we used the TH-MYCN mouse model of neuroblastoma to investigate the antitumor activity of the pan-HDAC inhibitor, panobinostat. In particular we sought to explore the impact of long term, continuous panobinostat exposure on the epigenetically driven differentiation process. Continuous treatment of tumor bearing TH-MYCN transgenic mice with panobinostat for nine weeks led to a significant improvement in survival as compared with mice treated with panobinostat for a three-week period. Panobinostat induced rapid tumor regression with no regrowth observed following a nine-week treatment period. Initial tumor response was associated with apoptosis mediated via upregulation of BMF and BIM. The process of terminal differentiation of neuroblastoma into benign ganglioneuroma, with a characteristic increase in S100 expression and reduction of N-Myc expression, occurred following prolonged exposure to the drug. RNA-sequencing analysis of tumors from treated animals confirmed significant upregulation of gene pathways associated with apoptosis and differentiation. Together our data demonstrate the potential of panobinostat as a novel therapeutic strategy for high-risk neuroblastoma patients.

  11. Toxicological Effects of Caco-2 Cells Following Short-Term and Long-Term Exposure to Ag Nanoparticles

    Science.gov (United States)

    Chen, Ni; Song, Zheng-Mei; Tang, Huan; Xi, Wen-Song; Cao, Aoneng; Liu, Yuanfang; Wang, Haifang

    2016-01-01

    Extensive utilization increases the exposure of humans to Ag nanoparticles (NPs) via the oral pathway. To comprehensively address the action of Ag NPs to the gastrointestinal systems in real situations, i.e., the long-term low-dose exposure, we evaluated and compared the toxicity of three Ag NPs (20–30 nm with different surface coatings) to the human intestine cell Caco-2 after 1-day and 21-day exposures, using various biological assays. In both the short- and long-term exposures, the variety of surface coating predominated the toxicity of Ag NPs in a descending order of citrate-coated Ag NP (Ag-CIT), bare Ag NP (Ag-B), and poly (N-vinyl-2-pyrrolidone)-coated Ag NP (Ag-PVP). The short-term exposure induced cell growth inhibition and death. The cell viability loss appeared after cells were exposed to 0.7 μg/mL Ag-CIT, 0.9 μg/mL Ag-B or >1.0 μg/mL Ag-PVP for 24 h. The short-term and higher-dose exposure also induced reactive oxygen species (ROS) generation, mitochondrial damage, cell membrane leakage, apoptosis, and inflammation (IL-8 level). The long-term exposure only inhibited the cell proliferation. After 21-day exposure to 0.4 μg/mL Ag-CIT, the cell viability dropped to less than 50%, while cells exposed to 0.5 μg/mL Ag-PVP remained normal as the control. Generally, 0.3 μg/mL is the non-toxic dose for the long-term exposure of Caco-2 cells to Ag NPs in this study. However, cells presented inflammation after exposure to Ag NPs with the non-toxic dose in the long-term exposure. PMID:27338357

  12. Toxicological Effects of Caco-2 Cells Following Short-Term and Long-Term Exposure to Ag Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ni Chen

    2016-06-01

    Full Text Available Extensive utilization increases the exposure of humans to Ag nanoparticles (NPs via the oral pathway. To comprehensively address the action of Ag NPs to the gastrointestinal systems in real situations, i.e., the long-term low-dose exposure, we evaluated and compared the toxicity of three Ag NPs (20–30 nm with different surface coatings to the human intestine cell Caco-2 after 1-day and 21-day exposures, using various biological assays. In both the short- and long-term exposures, the variety of surface coating predominated the toxicity of Ag NPs in a descending order of citrate-coated Ag NP (Ag-CIT, bare Ag NP (Ag-B, and poly (N-vinyl-2-pyrrolidone-coated Ag NP (Ag-PVP. The short-term exposure induced cell growth inhibition and death. The cell viability loss appeared after cells were exposed to 0.7 μg/mL Ag-CIT, 0.9 μg/mL Ag-B or >1.0 μg/mL Ag-PVP for 24 h. The short-term and higher-dose exposure also induced reactive oxygen species (ROS generation, mitochondrial damage, cell membrane leakage, apoptosis, and inflammation (IL-8 level. The long-term exposure only inhibited the cell proliferation. After 21-day exposure to 0.4 μg/mL Ag-CIT, the cell viability dropped to less than 50%, while cells exposed to 0.5 μg/mL Ag-PVP remained normal as the control. Generally, 0.3 μg/mL is the non-toxic dose for the long-term exposure of Caco-2 cells to Ag NPs in this study. However, cells presented inflammation after exposure to Ag NPs with the non-toxic dose in the long-term exposure.

  13. Effects of intermittent binge alcohol exposure on long-term motor function in young rats.

    Science.gov (United States)

    Forbes, Ashley; Cooze, Jared; Malone, Craig; French, Vanessa; Weber, John T

    2013-03-01

    Ethanol has well described acute effects on motor function, and chronic alcoholism can damage the cerebellum, which is associated with motor coordination, as well as motor learning. Binge drinking is common among preadolescents and adolescents, and this type of ethanol exposure may lead to long-term nervous system damage. In the current study, we analyzed the effects of periadolsecent/adolescent ethanol exposure on motor function in both male and female Sprague-Dawley rats. To simulate binge drinking, animals received an intraperitoneal injection of 25% (v/v) ethanol (3 g/kg) on postnatal days (PND) 25, 26, 29, 30, 33, 34, 37 and 38. On PND 42 and PND 61 animals were tested on their ability to traverse both square and round beams. There were no significant differences in the time to traverse the beams, or the amount of foot slips, between treated and untreated animals. On PND 48 and PND 62, animals were tested using a horizontal ladder walking apparatus. On PND 48 there were no differences in the ability of treated and untreated animals to traverse the ladder. On PND 62, there were no differences in the time to traverse the ladder, but ethanol treated animals had more foot slips than controls. On PND 43, we conducted footprint analysis of control and treated animals, which included measurements of stride length, paw overlap, and angle of foot placement. There was a significant difference in the angle of foot placement between treated and control animals, and this finding was significant for both male and female animals. There was also a significant overall difference in paw overlap between treatment groups. Although this effect was manifested in male animals there was no significant difference in females. These findings suggest that adolescent ethanol exposure can produce long-lasting effects on motor coordination, and that overall, effects are similar in males and females. In a second set of experiments, male rats received i.p. ethanol (3 g/kg) for 7 days (P31

  14. Hedging Long-Term Exposures of a Well-Diversified Portfolio with Short-Term Stock Index Futures Contracts

    Directory of Open Access Journals (Sweden)

    Yufang Liu

    2014-01-01

    Full Text Available It is difficult for passive portfolio strategy to manage the long-term exposure of a well-diversified portfolio because stock index futures contracts have a finite life limited by their maturity. In this paper, we investigate the problem of the rollover hedge strategy for the long-term exposure of a well-diversified portfolio. First, we consider the rollover hedge strategy for the well-diversified portfolio when the portfolio is not adjusted during the period. In order to obtain the optimal solution of the proposed model, the auxiliary models are constructed using the equivalent transformation technique. Moreover, dynamic programming is employed to derive the optimal positions of stock index futures contracts for the long-term exposure of the well-diversified portfolio. In addition, we extend the result to the case of the rollover hedge strategy with transaction costs and derive the optimal number of stock index futures contracts.

  15. Quantitative imaging of arsenic and its species in goat following long term oral exposure.

    Science.gov (United States)

    Patra, Pabitra Hriday; Bandyopadhyay, Samiran; Kumar, Rakesh; Datta, Bakul Kumar; Maji, Chinmoy; Biswas, Suman; Dash, Jeevan Ranjan; Sar, Tapas Kumar; Sarkar, Samar; Manna, Sanjib K; Chakraborty, Animesh Kumar; Mandal, Tapan Kumar

    2012-06-01

    Severity of arsenic toxicity was reported to vary depending on its species. The present study reflects the status of different species of arsenic in goat following long-term exposure of arsenic leading to hepatic damage. The experiment was conducted with six black Bengal goats, which were administered with sodium arsenite orally at a dose rate of 2 mgkg(-1) daily for 84 days. Faeces, urine, hair and blood samples were collected from those animals at 14 days interval. Excretion of total arsenic was reduced from 56 days onwards through both faeces and urine indicating higher accumulation of arsenic in body. The speciation study revealed that urinary arsenic was mainly of organic type, whereas hair accumulated almost equal proportion of arsenite, arsenate and organo arsenicals. Goats excreted high proportion of organo arsenicals through faeces possibly due to hepatobiliary secretion of organo arsenic into the gut. Significantly elevated serum alanine aminotransferase and aspartate aminotransferase activities (pgoat. The study thus alluded that the toxicity of arsenic would aggravate if the animals were exposed for long time as the hepatotoxicity progressed resulting in decreased methylation and formation of organo arsenicals and decreased excretions through urine. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Perception of affordances during long-term exposure to weightlessness in the International Space station.

    Science.gov (United States)

    Bourrelly, Aurore; McIntyre, Joseph; Luyat, Marion

    2015-09-01

    On Earth, visual eye height (VEH)--the distance from the observer's line of gaze to the ground in the visual scene--constitutes an effective cue in perceiving affordance such as the passability through apertures, based on the assumption that one's feet are on the ground. In the present study, we questioned whether an observer continues to use VEH to estimate the width of apertures during long-term exposure to weightlessness, where contact with the floor is not required. Ten astronauts were tested in preflight, inflight in the International Space Station, and postflight sessions. They were asked to adjust the opening of a virtual doorway displayed on a laptop device until it was perceived to be just wide enough to pass through (i.e., the critical aperture). We manipulated VEH by raising and lowering the level of the floor in the visual scene. We observed an effect of VEH manipulation on the critical aperture. When VEH decreased, the critical aperture decreased too, suggesting that widths relative to the body were perceived to be larger when VEH was smaller. There was no overall significant session effect, but the analysis of between-subjects variability revealed two participant profile groups. The effect of weightlessness was different for these two groups even though the VEH strategy remained operational during spaceflight. This study shows that the VEH strategy appears to be very robust and can be used, if necessary, in inappropriate circumstances such as free-floating, perhaps promoted by the nature of the visual scene.

  17. Long-term air pollution exposure and diabetes in a population-based Swiss cohort.

    Science.gov (United States)

    Eze, Ikenna C; Schaffner, Emmanuel; Fischer, Evelyn; Schikowski, Tamara; Adam, Martin; Imboden, Medea; Tsai, Ming; Carballo, David; von Eckardstein, Arnold; Künzli, Nino; Schindler, Christian; Probst-Hensch, Nicole

    2014-09-01

    Air pollution is an important risk factor for global burden of disease. There has been recent interest in its possible role in the etiology of diabetes mellitus. Experimental evidence is suggestive, but epidemiological evidence is limited and mixed. We therefore explored the association between air pollution and prevalent diabetes, in a population-based Swiss cohort. We did cross-sectional analyses of 6392 participants of the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults [SAPALDIA], aged between 29 and 73 years. We used estimates of average individual home outdoor PM10 [particulate matter pollutant model. There was some indication that beta blockers mitigated the effect of PM10. The associations remained stable across different sensitivity analyses. Our study adds to the evidence that long term air pollution exposure is associated with diabetes mellitus. PM10 appears to be a useful marker of aspects of air pollution relevant for diabetes. This association can be observed at concentrations below air quality guidelines.

  18. Histological examination of the rat after long-term exposure to subtoxic automotive exhaust gas.

    Science.gov (United States)

    Roggendorf, W; Neumann, H; Thron, H L; Schneider, H; Sarasa-Corral, J L

    1981-07-01

    Regarding the potential impact of traffic-born air pollutants on public health, in recent years attention has increasingly been focused on the possible effects on the cardiovascular system. In order to investigate this problem further, the influence of long-term exhaust gas exposure on rats has been studied. One hundred Wistar rats of either sex were exposed 5 X 8 h/week up to 28 months to an atmosphere polluted by the emissions of an idling Otto engine, CO concentrations held constant at 90 ppm. A second group (50 rats) was exposed to 250 ppm for 6 months. Blood parameters and body weight were controlled. Specimens of CNS, heart, vessels, kidney etc. were investigated light microscopically. Focal necroses of the myocardium with inflammatory reactions as well as interstitial fibrosis were found in the heart muscle of the 90 ppm group. In the 250 ppm group endothelial proliferations, edema of the intima and deposits of proteoglycanes in the media were observed. We conclude that subtoxic concentrations of CO which only lead to slight morphologic changes may aggravate preexisting lesions caused by high risk conditions, e.g., hypertension or hypercholesteremia.

  19. Performance of multilayer optical coatings under long-term 532nm laser exposure

    Science.gov (United States)

    Poulios, D.; Konoplev, O.; Chiragh, F.; Vasilyev, A.; Stephen, M.; Strickler, K.

    2013-11-01

    The effects of long-term exposure to high intensity 532 nm radiation on various dielectric-coated optics are studied. To investigate potential photodarkening effects on optical surfaces, an accelerated life test platform was constructed where optics were exposed to 532 nm radiation from a short-pulse, high repetition rate fiber amplifier at total doses up to 1 trillion shots. The first run of trillion-shot tests were conducted on e-beam deposited and ion beam sputtering (IBS) coated high reflecting mirrors with onsurface intensities ranging from 1.0-1.4 GW/cm2. It was found that the e-beam coated mirrors failed catastrophically at less than 150 billion shots, while the IBS coated mirror was able to complete the trillionshot test with no measurable loss of reflectivity. Profiling the IBS mirror surface with a high-resolution white light interferometer post-irradiation revealed a ~10 nm high photocontamination deposit at the irradiation site that closely matched the intensity profile of the laser spot. Trillion-shot surface exposure tests were also conducted at multiple surface sites of an LBO frequency doubling crystal at ~1.5 GW/cm2 at multiple surface sites. The transmitted power and on-surface beam size were monitored throughout the tests, and periodic measurements of the beam quality and waist location of the transmitted light were also made using an M2 meter. No changes in transmitted power or M2 were observed in any of the tests, but 3D surface profiling revealed laser-induced contamination deposits at each site tested.

  20. Self-reported Occupational Skin Exposure and Risk of Physician-certified Long-term Sick Leave

    DEFF Research Database (Denmark)

    Alfonso, Jose Hernan; Tynes, Tore; Thyssen, Jacob P;

    2016-01-01

    Little is known about the contribution of occupational skin exposure as a risk factor for physician-certified long-term sick leave in the general working population of Norway. This study drew a cohort (n = 12,255; response at baseline 69.9%) randomly from the general population of Norway. Occupat......Little is known about the contribution of occupational skin exposure as a risk factor for physician-certified long-term sick leave in the general working population of Norway. This study drew a cohort (n = 12,255; response at baseline 69.9%) randomly from the general population of Norway...

  1. Biological effects of long-term exposure to low dose-rate radiation -- Comparisons of WAM model and LQ model

    CERN Document Server

    Wada, Takahiro; Nakamura, Issei; Tsunoyama, Yuichi; Nakajima, Hiroo; Bando, Masako

    2015-01-01

    Newly proposed Whack-A-Mole (WAM) model which is to be used to estimate the biological effects of artificial radiations is compared with conventionally used Linear-Quadratic model. Basic properties of WAM model are discussed emphasizing on the dose-rate dependence. By adopting the parameters that are determined to fit the mega mouse experiments, biological effects of long-term exposure to extremely low dose-rate radiation are discussed. In WAM model, the effects of the long-term exposure show a saturation property, which makes a clear distinction from the LNT hypothesis which predicts a linear increase of the effects with time.

  2. Long-Term CO2 Exposure Experiments - Geochemical Effects on Brine-Saturated Reservoir Sandstone

    Science.gov (United States)

    Fischer, Sebastian; Zemke, Kornelia; Liebscher, Axel; Wandrey, Maren

    2010-05-01

    The injection of CO2 into deep saline aquifers is the most promising strategy for the reduction of CO2 emissions to the atmosphere via long-term geological storage. The study is part of the CO2SINK project conducted at Ketzin, situated 40 km west of Berlin. There, food grade CO2 has been pumped into the Upper Triassic Stuttgart Formation since June 2008. The main objective of the experimental program is to investigate the effects of long-term CO2 exposure on the physico-chemical properties of the reservoir rock. To achieve this goal, core samples from observation well Ktzi 202 have been saturated with synthetic brine and exposed to CO2 in high quality steel autoclaves at simulated reservoir P-T-conditions of 5.5 MPa and 40 ° C. The synthetic brine had a composition representative of the formation fluid (Förster et al., 2006) of 172.8 g/l NaCl, 8.0 g/l MgCl2×2H2O, 4.8 g/l CaCl2×2H2O and 0.6 g/l KCl. After 15 months, the first set of CO2-exposed samples was removed from the pressure vessels. Thin sections, XRD, SEM as well as EMP data were used to determine the mineralogical features of the reservoir rocks before and after the experiments. Additionally, NMR relaxation and MP was performed to measure poroperm and pore size distribution values of the twin samples. The analyzed samples are fine- to medium grained, moderately well- to well sorted and weakly consolidated sandstones. Quartz and plagioclase are the major components, while K-feldspar, hematite, white & dark mica, chlorite and illite are present in minor and varying amounts. Cements are composed of analcime, dolomite and anhydrite. Some samples show mm- to cm-scale cross-beddings. The laminae comprise lighter, quartz- and feldspar-dominated layers and dark-brownish layers with notably less quartz and feldspars. The results are consistent with those of Blaschke et al. (2008). The plagioclase composition indicates preferred dissolution of the Ca-component and a trend toward albite-rich phases or even pure

  3. A long-term rock uplift rate for eastern Crete from exposure dating of marine terraces

    Science.gov (United States)

    Strobl, M.; Hetzel, R.; Ivy-Ochs, S.; Alfimov, V.; Kubik, P. W.; Fassoulas, C.; Palumbo, L.

    2009-04-01

    The island of Crete in the forearc of the Hellenic subduction zone has a rugged topography with a relief exceeding 2 km. Rock uplift rates of 2-4 mm/a were estimated previously from raised Late Holocene shorelines (Lambeck, 1995) but may not be representative on longer timescales, because earthquakes with up to 9 m of coseismic uplift have recently affected Crete (Stiros, 2001). Here we use marine terraces near Kato Zakros to quantify the long-term rock uplift rate for eastern Crete. Our field investigations and topographic profiles document a flight of at least 15 marine bedrock terraces carved into limestone bedrock. Age constraints for the terraces were obtained by 36Cl exposure dating of bedrock samples and 10Be dating of sandstone cobbles found on some terraces. Our results suggest that the terraces T4 and T5 at elevations of 68 and 76 m, respectively, formed during sea level highstands associated with marine isotope stage 5e, i.e. ~125 ka ago. Correlating the other terraces (T1 to T11) to a sea-level curve for the Red Sea (Siddall et al., 2003) indicates an uplift rate of 0.5-0.6 mm/a during the last 400 ka; significantly lower than previous estimates based on the elevation of Late Holocene shorelines. References Lambeck, K. (1995), Late Pleistocene and Holocene sea-level change in Greece and SW Turkey - a separation of eustatic, isostatic and tectonic contributions. Geophys. J. Int. 122, 1022-1044. Siddall, M., Rohling, E.J., Almogi-Labin, A., Hemleben, C., Meischner, D., Schmelzer, I., and Smeed, D.A. (2003), Sea-level fluctuations during the last glacial cycle. Nature, 423, 853-858. Stiros, S.C. (2001), The AD 365 Crete earthquake and possible seismic clustering during the fourth to sixth centuries AD in the Eastern Mediterranean: a review of historical and archaeological data. J. Struct. Geol., 23, 545-562.

  4. Change of Exposure Response over Time and Long-Term Risk of Silicosis among a Cohort of Chinese Pottery Workers

    Directory of Open Access Journals (Sweden)

    Yuewei Liu

    2011-07-01

    Full Text Available An analysis was conducted on a cohort of Chinese pottery workers to estimate the exposure-response relationship between respirable crystalline silica dust exposure and the incidence of radiographically diagnosed silicosis, and to estimate the long-term risk of developing silicosis until the age of 65. The cohort comprised 3,250 employees with a median follow-up duration of around 37 years. Incident cases of silicosis were identified via silicosis registries (Chinese X-ray stage I, similar to International Labor Organisation classification scheme profusion category 1/1. Individual exposure to respirable crystalline silica dust was estimated based on over 100,000 historical dust measurements. The association between dust exposure, incidence and long-time risk of silicosis was quantified by Poisson regression analysis adjusted for age and smoking. The risk of silicosis depended not only on the cumulative respirable crystalline silica dust exposures, but also on the time-dependent respirable crystalline silica dust exposure pattern (long-term average concentration, highest annual concentration ever experienced and time since first exposure. A long-term “excess” risk of silicosis of approximately 1.5/1,000 was estimated among workers with all annual respirable crystalline silica dust concentration estimates less than 0.1 mg/m3, using the German measurement strategy. This study indicates the importance of proper consideration of exposure information in risk quantification in epidemiological studies.

  5. Long-term exposure to PGE2 causes homologous desensitization of receptor-mediated activation of protein kinase A.

    Science.gov (United States)

    Malty, Ramy Habashy; Hudmon, Andy; Fehrenbacher, Jill C; Vasko, Michael R

    2016-07-11

    Acute exposure to prostaglandin E2 (PGE2) activates EP receptors in sensory neurons which triggers the cAMP-dependent protein kinase A (PKA) signaling cascade resulting in enhanced excitability of the neurons. With long-term exposure to PGE2, however, the activation of PKA does not appear to mediate persistent PGE2-induced sensitization. Consequently, we examined whether homologous desensitization of PGE2-mediated PKA activation occurs after long-term exposure of isolated sensory neurons to the eicosanoid. Sensory neuronal cultures were harvested from the dorsal root ganglia of adult male Sprague-Dawley rats. The cultures were pretreated with vehicle or PGE2 and used to examine signaling mechanisms mediating acute versus persistent sensitization by exposure to the eicosanoid using enhanced capsaicin-evoked release of immunoreactive calcitonin gene-related peptide (iCGRP) as an endpoint. Neuronal cultures chronically exposed to vehicle or PGE2 also were used to study the ability of the eicosanoid and other agonists to activate PKA and whether long-term exposure to the prostanoid alters expression of EP receptor subtypes. Acute exposure to 1 μM PGE2 augments the capsaicin-evoked release of iCGRP, and this effect is blocked by the PKA inhibitor H-89. After 5 days of exposure to 1 μM PGE2, administration of the eicosanoid still augments evoked release of iCGRP, but the effect is not attenuated by inhibition of PKA or by inhibition of PI3 kinases. The sensitizing actions of PGE2 after acute and long-term exposure were attenuated by EP2, EP3, and EP4 receptor antagonists, but not by an EP1 antagonist. Exposing neuronal cultures to 1 μM PGE2 for 12 h to 5 days blocks the ability of PGE2 to activate PKA. The offset of the desensitization occurs within 24 h of removal of PGE2 from the cultures. Long-term exposure to PGE2 also results in desensitization of the ability of a selective EP4 receptor agonist, L902688 to activate PKA, but does not alter the ability of

  6. Toxic effects caused by a long-term exposure of Danio rerio to TiO2 nanoparticles.

    Directory of Open Access Journals (Sweden)

    Roberta Pecoraro

    2015-11-01

    In conclusion, the current study confirmed only a slight cytotoxicity of TiO2 NPs on zebrafish adults after a long-term exposure, however, further and wider studies are required to establish their effects on other organs and to evaluate the severity of their toxicity.

  7. Effects of long-term exposure to traffic-related air pollution on mortality and lung cancer

    NARCIS (Netherlands)

    Beelen, R.M.J.

    2008-01-01

    We assessed the association between long-term exposure to air pollution and cause-specific mortality and lung cancer incidence using data from an ongoing cohort study: the Netherlands Cohort Study on Diet and Cancer (NLCS). The NLCS study was initiated in September 1986 with the enrollment of 120,85

  8. Effects of long-term exposure to traffic-related air pollution on mortality and lung cancer

    NARCIS (Netherlands)

    Beelen, R.M.J.

    2008-01-01

    We assessed the association between long-term exposure to air pollution and cause-specific mortality and lung cancer incidence using data from an ongoing cohort study: the Netherlands Cohort Study on Diet and Cancer (NLCS). The NLCS study was initiated in September 1986 with the enrollment of

  9. Association Between Satellite-based Estimates of Long-term PM2.5 Exposure and Coronary Artery Disease

    Science.gov (United States)

    Background: Epidemiological studies have identified associations between long-term PM2.5 exposure and cardiovascular events, though most have relied on concentrations from central-site air quality monitors. Methods: We utilized a cohort of 5679 patients who had undergone cardiac ...

  10. Long-term Exposure to Particulate Matter Constituents and the Incidence of Coronary Events in 11 European Cohorts

    DEFF Research Database (Denmark)

    Wolf, Kathrin; Stafoggia, Massimo; Cesaroni, Giulia;

    2015-01-01

    BACKGROUND: Long-term exposure to particulate matter (PM) has been associated with increased cardiovascular morbidity and mortality but little is known about the role of the chemical composition of PM. This study examined the association of residential long-term exposure to PM components with inc......BACKGROUND: Long-term exposure to particulate matter (PM) has been associated with increased cardiovascular morbidity and mortality but little is known about the role of the chemical composition of PM. This study examined the association of residential long-term exposure to PM components...... (PM2.5), and a priori selected constituents (copper, iron, nickel, potassium, silicon, sulfur, vanadium, and zinc) were estimated with land-use regression models. We used Cox proportional hazard models adjusted for a common set of confounders to estimate cohort-specific component effects...... with and without including PM mass, and random effects meta-analyses to pool cohort-specific results. RESULTS: A 100 ng/m³ increase in PM10 K and a 50 ng/m³ increase in PM2.5 K were associated with a 6% (hazard ratio and 95% confidence interval: 1.06 [1.01, 1.12]) and 18% (1.18 [1.06, 1.32]) increase in coronary...

  11. Association Between Satellite-based Estimates of Long-term PM2.5 Exposure and Coronary Artery Disease

    Science.gov (United States)

    Background: Epidemiological studies have identified associations between long-term PM2.5 exposure and cardiovascular events, though most have relied on concentrations from central-site air quality monitors. Methods: We utilized a cohort of 5679 patients who had undergone cardiac ...

  12. [Long-term effect of environmental cadmium exposure on human body's mineral metabolic balance].

    Science.gov (United States)

    Ling, H T; Huang, R; Liang, X X; Li, Z X; Wang, J; Tan, J B; Wu, S X; Wang, P; Chen, Z H; Huang, Q; Lyu, Y J; Jiang, Q; Yang, X F; Wu, Y N

    2016-04-01

    To investigate the effect of long-term exposure to environmental cadmium on eight mineral element's metabolic balance of human body. To choose a high cadmium area polluted by smelting and mining north of Guangdong province and a cadmium-free area with a similar economic level, and living and eating habit of residents as a contrast from April 2011 to August 2012. Stratified random sampling and clustered sampling method were adopted to choose the non-occupationally cadmium-exposed respondents who have lived in local area for more than 15 years, older than 40 years, having local rice and vegetable as the main dietary source, with simple and relatively stable diet, and without diabetes, kidney disease, thyroid disease, liver disease or other history of chronic disease. This study included 298 respondents, of whom 155 were in cadmium exposure group and 143 in control group. Questionnaires was used to acquire their health status and their morning urine samples were collected. Electrolytically coupled plasma mass spectrometry (ICP-MS) was used to test the concentrations of sodium(Na), magnesium (Mg), phosphorus (P), potassium (K), calcium (Ca), copper (Cu), zinc (Zn) and iodine (I). The Mann-Whitney U test method was used to compare the differences of concentrations of urinary cadmium, Na, Mg, P, K, Ca, Cu, Zn, I, and the ratio of Na to K (Na/K), Ca to P (Ca/P) between exposed group and control group.χ(2) test was used to compare the abnormal rate of urinary cadmium between exposed group and control group. Pearson correlation and multiple regression method were used to investigate the relationship between urinary cadmium levels, gender, age, smoking, passive smoking, and minerals. The urinary cadmium level P50 (P25-P75) in exposed group was 5.45 (2.62-10.68) μg/g·cr, which was higher than that of the control group, which was 1.69 (1.22-2.36) μg/g·cr (Z=-10.49,Phuman body.

  13. Long-term exposure to arsenic affects head kidney and impairs humoral immune responses of Clarias batrachus

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Debabrata [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Datta, Soma [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Bhattacharya, Shelley [Environmental Toxicology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India); Mazumder, Shibnath [Immunobiology Laboratory, School of Life Sciences, Visva-Bharati University, Santiniketan 731235 (India)]. E-mail: shibnath1@yahoo.co.in

    2007-02-15

    The present study was aimed at determining the effects of long-term arsenic exposure on the head kidney (HK) and ensuing humoral immune responses in Clarias batrachus L. Long-term exposure (150 days) to non-lethal concentrations of arsenic (42.42 {mu}M) resulted in significant time-dependent alterations in HK cell number eventually affecting the HK somatic index. Prolonged exposure to arsenic also suppressed HK-B cell proliferation and led to significant reduction in serum immunoglobulin levels and antigen-specific serum bacterial agglutinin titers. A decline in the number of antigen-specific plaque-forming cells with duration of arsenic exposure was noted in the HK. Enzyme linked immunosorbent assays further revealed that arsenic exposure inhibited the release of 'IL-4 like factors' from HK-T cells. Histological studies documented time-dependent changes in the structure and cellular composition of HK characterized by extensive lymphocytopenia, decrease in melano-macrophage population and hemosiderin accumulation. From exposure-challenge studies with Aeromonas hydrophila it was evident that pathogens could efficiently disseminate and colonize distant host tissues in the exposed fish. Moreover, the ability to decrease the pathogen load was also significantly reduced in the arsenic-exposed fish. Thus long-term exposure to non-lethal concentrations of arsenic affects HK and interferes with the humoral immune system of C. batrachus rendering them immunocompromised and susceptible to pathogenic challenge.

  14. Long-term effect of early-life stress from earthquake exposure on working memory in adulthood

    OpenAIRE

    Li, Na; Wang, Yumei; Zhao, Xiaochuan; Gao, Yuanyuan; Song, Mei; Yu, Lulu; Wang, Lan; Li, Ning; Chen, Qianqian; Li, Yunpeng; Cai,Jiajia; Wang, Xueyi

    2015-01-01

    Objective The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood. Methods A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3–12 months, n=274), prenatal exposure (n=269), and no exposure (born at least 1 year after the earthquake, n=364). The prenatal group was further d...

  15. Long-term effect of maternal xylitol exposure on their children's caries prevalence

    DEFF Research Database (Denmark)

    Thorild, I; Lindau, B; Twetman, S

    2012-01-01

    Aim: To evaluate the long-term outcome of a motherchild project in which mothers (n=173) with high counts of salivary mutans streptococci were randomly assigned to daily chewing gums containing xylitol (A), chlorhexidine/ xylitol/sorbitol (B), or sodium fluoride/xylitol/sorbitol (C) for one year...

  16. Docosahexaenoic Acid Rescues Synaptogenesis Impairment and Long-Term Memory Deficits Caused by Postnatal Multiple Sevoflurane Exposures

    Directory of Open Access Journals (Sweden)

    Guorong Tao

    2016-01-01

    Full Text Available Sevoflurane exposures were demonstrated to induce neurotoxicity in the developing brain in both human and animal studies. However, there is no effective approach to reverse it. The present study aimed to evaluate the feasibility of utilizing docosahexaenoic acid (DHA to prevent sevoflurane-induced neurotoxicity. P6 (postnatal 6 days mice were administrated DHA after exposure to 3% sevoflurane for two hours daily in three consecutive days. Molecular expressions of synaptic makers (PSD95, synaptophysin and synaptic morphological changes were investigated by Western blot analysis and transmission electron microscopy, respectively. Meanwhile, Morris water maze test was used to assess spatial memory of mice at P31 (postnatal 31 days. DHA restored sevoflurane-induced decreased level of PSD95 and synaptophysin expressions and increased PSD areas and also improved long-term spatial memory. These results suggest that DHA could rescue synaptogenesis impairment and long-term memory deficits in postnatal caused by multiple sevoflurane exposures.

  17. Long-Term Exposure to Ambient Air Pollution and Subclinical Cerebrovascular Disease in NOMAS (the Northern Manhattan Study).

    Science.gov (United States)

    Kulick, Erin R; Wellenius, Gregory A; Kaufman, Joel D; DeRosa, Janet T; Kinney, Patrick L; Cheung, Ying Kuen; Wright, Clinton B; Sacco, Ralph L; Elkind, Mitchell S

    2017-07-01

    Long-term exposure to ambient air pollution is associated with higher risk of cardiovascular disease and stroke. We hypothesized that long-term exposure to air pollution would be associated with magnetic resonance imaging markers of subclinical cerebrovascular disease. Participants were 1075 stroke-free individuals aged ≥50 years drawn from the magnetic resonance imaging subcohort of the Northern Manhattan Study who had lived at the same residence for at least 2 years before magnetic resonance imaging. Cross-sectional associations between ambient air pollution and subclinical cerebrovascular disease were analyzed. We found an association between distance to roadway, a proxy for residential exposure to traffic pollution, and white matter hyperintensity volume; however, after adjusting for risk factors, this relationship was no longer present. All other associations between pollutant measures and white matter hyperintensity volume were null. There was no clear association between exposure to air pollutants and subclinical brain infarcts or total cerebral brain volume. We found no evidence that long-term exposure to ambient air pollution is independently associated with subclinical cerebrovascular disease in an urban population-based cohort. © 2017 American Heart Association, Inc.

  18. Sevoflurane exposure during the neonatal period induces long-term memory impairment but not autism-like behaviors.

    Science.gov (United States)

    Chung, Woosuk; Park, Saegeun; Hong, Jiso; Park, Sangil; Lee, Soomin; Heo, Junyoung; Kim, Daesoo; Ko, Youngkwon

    2015-10-01

    To examine whether neonatal exposure to sevoflurane induces autism-like behaviors in mice. There are continuing reports regarding the potential negative effects of anesthesia on the developing brain. Recently, several studies suggest that neurotoxicity caused by anesthesia may lead to neurodevelopmental impairments. However, unlike reports focusing on learning and memory, there are only a few animal studies focusing on neurodevelopmental disorders after general anesthesia. Therefore, we have focused on autism, a representative neurodevelopmental disorder. Neonatal mice (P6-7) were exposed to a titrated dose of sevoflurane for 6 h. Apoptosis was evaluated by assessing the expression level of cleaved (activated) caspase-3. Autism-like behaviors, general activity, anxiety level, and long-term memory were evaluated with multiple behavioral assays. Western blotting confirmed that neonatal exposure to sevoflurane increased the expression level of activated caspase-3, indicative of apoptosis. Mice exposed to sevoflurane also showed impaired long-term memory in fear tests. However, sevoflurane-exposed mice did not exhibit autism-like features in all of the following assays: social interaction (three-chamber test, caged social interaction), social communication (ultrasonic vocalization test), or repetitive behavior (self-grooming test, digging). There were also no differences in general activity (open field test, home cage activity) and anxiety (open field test, light-dark box) after sevoflurane exposure. Our results confirm previous studies that neonatal sevoflurane exposure causes neurodegeneration and long-term memory impairment in mice. However, sevoflurane did not induce autism-like features. Our study suggests that mice are more vulnerable to long-term memory deficits than autism-like behaviors after exposure to sevoflurane. © 2015 John Wiley & Sons Ltd.

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

    Science.gov (United States)

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

    2015-09-22

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

  20. Long-Term Exposure to Traffic-Related Air Pollution and Risk of Incident Atrial Fibrillation

    DEFF Research Database (Denmark)

    Monrad, Maria; Sajadieh, Ahmad; Christensen, Jeppe Schultz

    2016-01-01

    BACKGROUND: Atrial fibrillation is the most common sustained arrhythmia and associated with cardiovascular morbidity and mortality. The few studies conducted on short-term effects of air pollution on episodes of atrial fibrillation indicates a positive association, though not consistently....... OBJECTIVES: The aim of this study was to evaluate the long-term impact of traffic-related air pollution on incidence of atrial fibrillation in the general population. METHODS: In the Danish Diet, Cancer, and Health cohort of 57,053 people aged 50-64 years at enrolment in 1993-1997, we identified 2,700 cases...... tendencies regarding effect modification of the association between NO2 and atrial fibrillation by sex, smoking, hypertension or myocardial infarction. CONCLUSION: We found long-term residential traffic-related air pollution to be associated with higher risk of atrial fibrillation. Accordingly, the present...

  1. Long term effect of monosodium glutamate in liver of albino mice after neo-natal exposure.

    Science.gov (United States)

    Bhattacharya, T; Bhakta, A; Ghosh, S K

    2011-03-01

    Mono Sodium Glutamate (MSG) is a naturally occurring excitatory neurotransmitter. It is extensively used as a food additive and flavoring agent for its UMAMI taste. Simultaneously it is being implicated for varied pathological condition like obesity, gonadal dysfunction, learning difficulty etc. It produces oxygen derived free radicals and metabolized in liver. Neonate mice are sensitive and suffer from adverse effects. Present work was undertaken to study the long term effects on histology of liver following MSG injection in neonates. The changes in the liver parenchyma of 75 days old mice showed variable changes. Areas around central vein were most affected. The liver cords were disrupted, dilated sinusoids, prominent Kupffer cells with accumulation of particulate matter.There were inflammatory cells around central vein. The hepatocyte cell membrane were disrupted, cytoplasm vacuolated, nucleus were pyknotic. Even the normal looking cells showed depletion of PAS +ve material in the cytoplasm.The long term effect on histology showed moderate and patchy hepatocellular damage.

  2. Peripheral blood and bone marrow cell status of white rats with long-term lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sudakova, A.I.; Shevchenko, Z.H.T.; Nosova, L.I.

    Blood test and bone marrow examination in experiments with albino rats weighing 100-110 g subjected to long-term lead influence (1% lead acetate per os) showed availability of reticulocytosis with thrombocytopenia (on the 62d day) and thrombocytosis on the 92d day of the experiment) in peripheral blood. Reduction of the bone marrow neutrophil index and leuko-erythroblastic ration due to an increase of an erythroblastic radicle was recorded in the bone marrow.

  3. Long-term trend of thyroid cancer risk among Japanese atomic-bomb survivors: 60 years after exposure.

    Science.gov (United States)

    Furukawa, Kyoji; Preston, Dale; Funamoto, Sachiyo; Yonehara, Shuji; Ito, Masahiro; Tokuoka, Shoji; Sugiyama, Hiromi; Soda, Midori; Ozasa, Kotaro; Mabuchi, Kiyohiko

    2013-03-01

    Thyroid cancer risk following exposure to ionizing radiation in childhood and adolescence is a topic of public concern. To characterize the long-term temporal trend and age-at-exposure variation in the radiation-induced risk of thyroid cancer, we analyzed thyroid cancer incidence data for the period from 1958 through 2005 among 105,401 members of the Life Span Study cohort of Japanese atomic-bomb survivors. During the follow-up period, 371 thyroid cancer cases (excluding those with microcarcinoma with a diameter 50 years after exposure. Copyright © 2012 UICC.

  4. A 20-year follow-up study on the effects of long-term exposure to thorium dust

    Institute of Scientific and Technical Information of China (English)

    陈兴安; 程永娥; 肖慧娟; 冯国栋; 邓芸辉; 冯志良; 陈莲; 韩轩茂; 杨英杰; 董智华; 甄荣

    2003-01-01

    Objective The purpose of this study is to investigate the possible effects of long-term exposure to dust containing thorium and thoron progeny dust-exposed miners. Methods A negative, high voltage, exhaled thoron progeny measurement system was used to estimate the miners' thorium lung burden. Results The highest thorium lung burden of 638 miners was 11.11 Bq. The incidence of stage 0+ pneumoconiosis was higher among dust-exposed miners. Lung cancer mortality of the dust-exposed miners was significantly higher than that of controls (P<0.005). Conclusion There is a difference in cancer rates between those who have long-term exposure to dust containing thorium (in which carcinogenic ThO2 and SiO2 exist) and thoron progeny and those who have not.

  5. Long-term Exposure to Ambient Air Pollution and Serum Leptin in Older Adults: Results from the MOBILIZE Boston Study

    Science.gov (United States)

    Wang, Yi; Eliot, Melissa N.; Kuchel, George A.; Schwartz, Joel; Coull, Brent A.; Mittleman, Murray A.; Lipsitz, Lewis A.; Wellenius, Gregory A.

    2014-01-01

    Objective Long-term exposure to traffic-related air pollution has been linked to increased risk of obesity and diabetes and may be associated with higher serum levels of the adipokine leptin, but this hypothesis has not been previously evaluated in humans. Methods In a cohort of older adults, we estimated the association between serum leptin concentrations and two markers of long-term exposure to traffic pollution, adjusting for participant characteristics, temporal trends, socioeconomic factors, and medical history. Results An interquartile range increase (0.11 µg/m3) in annual mean residential black carbon was associated with 12% (95% CI: 3%, 22%) higher leptin levels. Leptin levels were not associated with residential distance to major roadway. Conculsions If confirmed, these findings support the emerging evidence suggesting that certain sources of traffic pollution may be associated with adverse cardiometabolic effects. PMID:25192230

  6. Long-term ambient air pollution exposure and risk of high blood pressure among citizens in Nis, Serbia.

    Science.gov (United States)

    Stanković, Aleksandra; Nikolić, Maja

    2016-01-01

    Epidemiological studies suggest that long-term exposure to air pollution increases the risk for high blood pressure (BP). The aim of our study is to evaluate any effects in BP in citizens exposed to long-term ambient air pollution. The subjects are 1136 citizens, aged 18-70 years, living for more than 5 years in the same home in the areas with a different level of air pollution. The air concentrations of black smoke and sulfur dioxide were determined in the period from 2001 to 2011. We measured systolic and diastolic BP and heart rate. Multivariate methods were used in the analysis. Alcohol consumption had the greatest influence on the incidence of hypertension as a risk factor (RR: 3.461; 95% CI: 1.72-6.93) and age had the least (RR: 1.23; 95% CI: 1.183-1.92). Exposure to air pollution increases risk for developing hypertension 2.5 times (95% CI: 1.46-4.49). Physical activity has proved to be statistically significant protective factor for the development of hypertension. Long-term exposure to low levels of main air pollutants is significantly associated with elevated risk of hypertension.

  7. Long term/low dose formalin exposure to small-scale recirculation aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg; Nielsen, Jeppe L.

    2010-01-01

    Repetitive long term formalin application at low dose was investigated to determine the effect on formaldehyde removal rate, biofilter nitrification and the microbial composition in small-scale recirculation aquaculture biofilters. Six pilot-scale recirculation aquaculture systems holding rainbow...... Nitrobacter sp. was not detected. The relative abundances of AOB and NOB in the untreated system were generally higher compared to the system exposed to formalin. Low dose formalin in recirculated aquaculture systems proved to be a possible treatment strategy, as the effect on nitrification was minimal. Since...

  8. The long-term effects of prenatal nicotine exposure on response inhibition: an fMRI study of young adults.

    Science.gov (United States)

    Longo, Carmelinda A; Fried, Peter A; Cameron, Ian; Smith, Andra M

    2013-01-01

    The long-term effects of prenatal nicotine exposure on response inhibition were investigated in young adults using functional magnetic resonance imaging (fMRI). Participants were members of the Ottawa Prenatal Prospective Study, a longitudinal study that collected a unique body of information on participants from infancy to young adulthood, which allowed for the measurement of an unprecedented number of potentially confounding drug exposure variables including: prenatal marijuana and alcohol exposure and current marijuana, nicotine and alcohol use. Twelve young adults with prenatal nicotine exposure and 13 non-exposed controls performed a Go/No-Go task while fMRI blood oxygen level-dependent responses were examined. Despite similar task performance, participants prenatally exposed to nicotine demonstrated significantly greater activity in several regions of the brain that typically subserve response inhibition including the inferior frontal gyrus, the inferior parietal lobe, the thalamus and the basal ganglia. In addition, prenatally exposed participants showed greater activity in relatively large posterior regions of the cerebellum. These results suggest that prenatal nicotine exposure leads to altered neural functioning during response inhibition that continues into adulthood. This alteration is compensated for by recruitment of greater neural resources within regions of the brain that subserve response inhibition and the recruitment of additional brain regions to successfully perform the task. Response inhibition is an important executive functioning skill and impairments can impede functioning in much of everyday life. Thus, awareness of the continued long-term neural physiological effects of prenatal nicotine exposure is critical.

  9. INDUCTION OF CHRONIC KIDNEY FAILURE IN A LONG-TERM PERITONEAL EXPOSURE MODEL IN THE RAT: EFFECTS ON FUNCTIONAL AND STRUCTURAL PERITONEAL ALTERATIONS

    NARCIS (Netherlands)

    F. Vrtovsnik; A. Coester; D. Lopes-Barreto; D.R. de Waart; A. van der Wal; D.G. Struijk; R. Krediet; M. Zweers

    2010-01-01

    Background: A long-term peritoneal exposure model has been developed in Wistar rats. Chronic daily exposure to 3.86% glucose based, lactate buffered, conventional dialysis solutions is possible for up to 20 weeks and induces morphological abnormalities similar to those in long-term peritoneal dialys

  10. Effects of long-term exposure to air pollution on natural-cause mortality : an analysis of 22 European cohorts within the multicentre ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob|info:eu-repo/dai/nl/30483100X; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul; Nieuwenhuijsen, Mark; Vineis, Paolo; Xun, Wei W.; Katsouyanni, Klea; Dimakopoulou, Konstantina; Oudin, Anna; Forsberg, Bertil; Modig, Lars; Havulinna, Aki S.; Lanki, Timo; Turunen, Anu; Oftedal, Bente; Nystad, Wenche; Nafstad, Per; De Faire, Ulf; Pedersen, Nancy L.; Ostenson, Claes-Goeran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Goeran; Eriksen, Kirsten Thorup; Overvad, Kim; Ellermann, Thomas; Eeftens, Marloes|info:eu-repo/dai/nl/315028300; Peeters, Petra H.; Meliefste, Kees; Wang, Meng; Bueno-de-Mesquita, Bas; Sugiri, Dorothea; Kraemer, Ursula; Heinrich, Joachim; de Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Ineichen, Alex; Schaffner, Emmanuel; Probst-Hensch, Nicole; Kuenzli, Nino; Schindler, Christian; Schikowski, Tamara; Adam, Martin; Phuleria, Harish; Vilier, Alice; Clavel-Chapelon, Francoise; Declercq, Christophe; Grioni, Sara; Krogh, Vittorio; Tsai, Ming-Yi; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Tamayo, Ibon; Amiano, Pilar; Dorronsoro, Miren; Katsoulis, Michail; Trichopoulou, Antonia; Brunekreef, Bert|info:eu-repo/dai/nl/067548180; Hoek, Gerard|info:eu-repo/dai/nl/069553475

    2014-01-01

    Background Few studies on long-term exposure to air pollution and mortality have been reported from Europe. Within the multicentre European Study of Cohorts for Air Pollution Effects (ESCAPE), we aimed to investigate the association between natural-cause mortality and long-term exposure to several

  11. Long-term exposure to elemental constituents of particulate matter and cardiovascular mortality in 19 European cohorts : Results from the ESCAPE and TRANSPHORM projects

    NARCIS (Netherlands)

    Wang, Meng; Beelen, Rob; Stafoggia, Massimo; Raaschou-Nielsen, Ole; Andersen, Zorana Jovanovic; Hoffmann, Barbara; Fischer, Paul; Houthuijs, Danny; Nieuwenhuijsen, Mark; Weinmayr, Gudrun; Vineis, Paolo; Xun, Wei W.; Dimakopoulou, Konstantina; Samoli, Evangelia; Laatikainen, Tiina; Lanki, Timo; Turunen, Anu W.; Oftedal, Bente; Schwarze, Per; Aamodt, Geir; Penell, Johanna; De Faire, Ulf; Korek, Michal; Leander, Karin; Pershagen, Goran; Pedersen, Nancy L.; Ostenson, Claes-Goran; Fratiglioni, Laura; Eriksen, Kirsten Thorup; Sorensen, Mette; Tjonneland, Anne; Bueno-de-Mesquita, Bas; Eeftens, Marloes; Bots, Michiel L.; Meliefste, Kees; Kraemer, Ursula; Heinrich, Joachim; Sugiri, Dorothea; Key, Timothy; de Hoogh, Kees; Wolf, Kathrin; Peters, Annette; Cyrys, Josef; Jaensch, Andrea; Concin, Hans; Nagel, Gabriele; Tsai, Ming-Yi; Phuleria, Harish; Ineichen, Alex; Kuenzli, Nino; Probst-Hensch, Nicole; Schaffner, Emmanuel; Vilier, Alice; Clavel-Chapelon, Francoise; Declerq, Christophe; Ricceri, Fulvio; Sacerdote, Carlotta; Marcon, Alessandro; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Katsoulis, Michail; Trichopoulou, Antonia; Keuken, Menno; Jedynska, Aleksandra; Kooter, Ingeborg M.; Kukkonen, Jaakko; Sokhi, Ranjeet S.; Brunekreef, Bert; Katsouyanni, Klea; Hoek, Gerard

    2014-01-01

    Background: Associations between long-term exposure to ambient particulate matter (PM) and cardiovascular (CVD) mortality have been widely recognized. However, health effects of long-term exposure to constituents of PM on total CVD mortality have been explored in a single study only. Aims: The aim o

  12. Effects of long-term exposure to air pollution on natural-cause mortality : an analysis of 22 European cohorts within the multicentre ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul; Nieuwenhuijsen, Mark; Vineis, Paolo; Xun, Wei W.; Katsouyanni, Klea; Dimakopoulou, Konstantina; Oudin, Anna; Forsberg, Bertil; Modig, Lars; Havulinna, Aki S.; Lanki, Timo; Turunen, Anu; Oftedal, Bente; Nystad, Wenche; Nafstad, Per; De Faire, Ulf; Pedersen, Nancy L.; Ostenson, Claes-Goeran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Goeran; Eriksen, Kirsten Thorup; Overvad, Kim; Ellermann, Thomas; Eeftens, Marloes; Peeters, Petra H.; Meliefste, Kees; Wang, Meng; Bueno-de-Mesquita, Bas; Sugiri, Dorothea; Kraemer, Ursula; Heinrich, Joachim; de Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Ineichen, Alex; Schaffner, Emmanuel; Probst-Hensch, Nicole; Kuenzli, Nino; Schindler, Christian; Schikowski, Tamara; Adam, Martin; Phuleria, Harish; Vilier, Alice; Clavel-Chapelon, Francoise; Declercq, Christophe; Grioni, Sara; Krogh, Vittorio; Tsai, Ming-Yi; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Tamayo, Ibon; Amiano, Pilar; Dorronsoro, Miren; Katsoulis, Michail; Trichopoulou, Antonia; Brunekreef, Bert; Hoek, Gerard

    2014-01-01

    Background Few studies on long-term exposure to air pollution and mortality have been reported from Europe. Within the multicentre European Study of Cohorts for Air Pollution Effects (ESCAPE), we aimed to investigate the association between natural-cause mortality and long-term exposure to several a

  13. Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

    OpenAIRE

    2016-01-01

    It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood bi...

  14. Morphological changes in the pineal gland of rats under conditions of long-term exposure to bright light.

    Science.gov (United States)

    Gerasimov, A V; Logvinov, S V; Kostyuchenko, V P

    2010-12-01

    Changes in the diurnal light cycle affect the morphofunctional state of the pineal gland. The volume of the nucleus, Golgi apparatus, and mitochondria in pinealocytes decreases after 45-day exposure to bright light. After 90 days, the degree of nuclear polymorphism increased, the specific volume of the Golgi apparatus returned to normal, the volume of the granular endoplasmic reticulum decreased, while the volume of lysosomes, free ribosomes, and polysomes increased. These changes reflect plasticity of pinealocytes and adaptation of the gland to long-term 24-h light exposure.

  15. 长期服用他莫昔芬致重度脂肪肝%Severe hepatic steatosis caused by long-term use of tamoxifen

    Institute of Scientific and Technical Information of China (English)

    杨杰; 于磊; 邹丹; 鲁憬丽; 王进; 张晓坚

    2016-01-01

    1例51岁女性乳腺癌患者术后服用枸橼酸他莫昔芬(10 mg,2次/d)40个月,停药1、8个月后常规体检提示脂肪肝,停药后约13个月腹部CT检查提示重度脂肪肝。患者肝功能正常,无相关症状出现。为明确诊断行肝穿刺活体组织检查术,组织病理学检查显示约60%肝细胞呈大泡性脂肪变性,约30%肝细胞呈小泡性脂肪变性,证实存在重度脂肪肝。给予多烯磷脂酰胆碱10 ml、还原型谷胱甘肽1.2 g静脉滴注,1次/d。3 d后停用保肝药物。随访18个月,患者腹部超声检查示脂肪肝未进一步发展。%A 51-year-old female patient with breast cancer received tamoxifen citrate(10 mg,twice daily)for 40 months after surgery. Routine physical examinations 1 and 8 months after drug withdrawal showed mild fatty liver. Abdominal CT examination showed severe fatty liver about 13 months after drug withdrawal. The liver function was normal and no related symptoms appeared. Liver biopsy was performed and histopathological examination showed that about 60% liver cells appeared macrovesicular steatosis and approximately 30% liver cells in microvesicular steatosis. severe fatty liver was confirmed. IV in fusion of phosphatidylcholine 10 ml and glutathione 1. 2 g once daily were given. Three days later,the above-mentioned drugs were stopped. At 18 months of follow-up,the abdominal ultrasonography examination showed no further development in the patient's fatty liver.

  16. The long-term effects of the herbicide atrazine on the dopaminergic system following exposure during pubertal development.

    Science.gov (United States)

    Li, Yanshu; Sun, Yan; Yang, Junwei; Wu, Yanping; Yu, Jia; Li, Baixiang

    2014-03-15

    Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is used worldwide as a herbicide, and its presence in the environment has resulted in documented human exposure. Atrazine has been shown to cause dopaminergic neurotoxicity. The juvenile period is particularly vulnerable to environmental agents, but only few studies have investigated the long-term effects of atrazine following exposure during the pubertal development. Therefore, we evaluated the effects of a 41-day exposure to atrazine on the dopaminergic system in rats. Sprague-Dawley rats were treated orally with atrazine at 25 or 50mg/kg bw, daily from postnatal day 22 to 62. The content of dopamine (DA) was examined in striatum samples by HPLC-FL, and the mRNA and protein expression of tyrosine hydroxylase (TH), orphan nuclear hormone (Nurr1), dopamine transporter (DAT) and vesicular monoaminetransporter 2 (VMAT2) were examined in samples of the ventral mid-brain by use of fluorescence PCR and Western-blot analysis when the rats reached the age of one year. Exposure of juvenile rats to the high dose of atrazine led to reduced levels of DA and mRNA of Nurr1 in one-year-old animals. This study shows that the long-term adverse effects of atrazine on the dopaminergic system have a special relevance after juvenile exposure.

  17. Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

    Science.gov (United States)

    Loiola, Rodrigo Azevedo; Dos Anjos, Fabyana Maria; Shimada, Ana Lúcia; Cruz, Wesley Soares; Drewes, Carine Cristiane; Rodrigues, Stephen Fernandes; Cardozo, Karina Helena Morais; Carvalho, Valdemir Melechco; Pinto, Ernani; Farsky, Sandra Helena

    2016-06-01

    It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood biochemical profile. Pancreatic toxicity was measured by inflammatory parameters, cell viability and cycle, free radical generation, and proteomic profile on islets of Langerhans. In vivo PCB126 exposure enhanced the body weight gain, impaired insulin sensitivity, reduced adipose tissue deposit, and elevated serum triglycerides, cholesterol, and insulin levels. Inflammatory parameters in the pancreas and cell morphology, viability and cycle were not altered in islets of Langerhans. Nevertheless, in vivo PCB126 exposure increased free radical generation and modified the expression of proteins related to oxidative stress on islets of Langerhans, which are indicative of early β-cell failure. Data herein obtained show that long-term in vivo PCB126 exposure through intranasal route induced alterations on islets of Langerhans related to early end points of DM2.

  18. Bacterial bioluminescence response to long-term exposure to reverse osmosis treated effluents from dye industries

    Digital Repository Service at National Institute of Oceanography (India)

    Ravindran, J.; Manikandan, B.; Shirodkar, P.V.; Francis, K.X.; ManiMurali, R.; Vethamony, P.

    effects upon exposure and retarded the growth of bacteria, confirming their toxic nature. Further, continuation of the exposure showed that the initial luminescence, though reduced, recovered and increased beyond the control cultures irrespective of cell...

  19. Long-term ethanol exposure decreases the endotoxin-induced hepatic acute phase response in rats

    DEFF Research Database (Denmark)

    Glavind, Emilie; Vilstrup, Hendrik; Grønbaek, Henning

    2017-01-01

    -fed rats showed either no liver histopathological changes or varying degrees of steatosis. Ethanol feeding decreased the spontaneous liver mRNA expression of the prevailing acute phase protein alpha-2-macroglobulin by 30% (Ptumor necrosis factor...... an induced acute phase response is impaired in long-term ethanol-fed rats. METHODS: For six weeks, rats were either fed a Lieber-DeCarli ethanol-containing (36% as calories) liquid diet ad libitum or calorically pair-fed. Then, the rats were injected intraperitoneally with a low-dose of lipopolysaccharide...... (LPS) (0.5 mg/kg) to induce an acute phase response. Two hours after LPS, we measured the plasma concentrations of an array of inflammatory cytokines. Twenty-four hours after LPS, we measured the hepatic mRNA expression and serum concentrations of prominent rat acute phase proteins. RESULTS: Ethanol...

  20. Health effects of long-term exposure to air pollution: An overview of major respiratory and cardiovascular diseases and diabetes

    Directory of Open Access Journals (Sweden)

    Jovanovic-Andersen Zorana

    2012-01-01

    Full Text Available Large number of studies provided convincing evidence for adverse effects of exposure to outdoor air pollution on human health, and served as basis for current USA and EU Air Quality Standards and limit values. Still, new knowledge is emerging, expanding our understanding of vast effects of exposure to air pollution on human health of this ubiquitous exposure affecting millions of people in urban setting. This paper focuses on the studies of health effects of long-term (chronic exposures to air pollution, and includes major chronic and acute diseases in adults and especially elderly, which will present increasing public health burden, due to improving longevity and projected increasing numbers of elderly. The paper gives overview over the most relevant and latest literature presented by different health outcomes: chronic obstructive pulmonary disease, asthma, pneumonia, cardiovascular disease, and diabetes.

  1. Low frequency electromagnetic fields long-term exposure effects on testicular histology, sperm quality and testosterone levels of male rats

    Institute of Scientific and Technical Information of China (English)

    Aminollah Bahaodini; Maryam Owjfard; Amin Tamadon; Seyedeh Marzieh Jafari

    2015-01-01

    Objective:To evaluate the effects of long-term exposure to low frequency EMF on the testicular function and structure.Methods:Fourteen adult male rats were randomly and equally divided into sham and experimental groups. Experimental group was exposed to 1 mT, 50 Hz EMF, continuously for 85 days in a solenoid. Sham group was kept under conditions same as experimental group, without EMF. At the end of the exposure period, weight and size of testes, sperm evaluation (sperm counts, motility and viability), histological testicular sections and serum total testosterone were determined.Results:Long-term exposure to low frequency EMF significantly decreased the diameter of the seminiferous tubules and increased number of seminiferous tubules per unit area of testes. In addition, low frequency EMF significantly reduced sperm motility and testosterone levels. However, it had no effect on the weight and size of testes, sperm concentration, and viability. Conclusion:Prolonged exposure to 50 Hz EMF has an adverse effect on male fertility.

  2. Fatigue of airway obstruction during long-term exposure to allergen aerosol.

    Science.gov (United States)

    Zimmermann, I; Curschmann, P; Kowalski, J; Ulmer, W T

    1977-12-15

    The response to prolonged antigen exposure and the potentiation of airway resistance increase to ACH challenge, after this exposure, were studied on sixteen boxer dogs. One group of animals presented fatigue to A.E. after 3 hours of exposure. This group developed an increased response to ACH aerosol after fatigue to antigen was present. In a second group of dogs, absence of fatigue during prolonged exposure to allergen was observed. A growing tendency of Edyn (as an index of airway resistance) was observed after 5 hours of exposure. The therapeutical influence of bilateral vagus blockade was tested in these last animals. Blockade of nervus vagus released airway obstruction during prolonged allergen exposure and no bronchoconstriction was observed after ACH challenge during blockade.

  3. Evaluation of long-term occupational exposure to styrene vapor on olfactory function.

    Science.gov (United States)

    Dalton, Pamela; Lees, Peter S J; Gould, Michele; Dilks, Daniel; Stefaniak, Aleksandr; Bader, Michael; Ihrig, Andreas; Triebig, Gerhard

    2007-10-01

    The primary sensory neurons of the olfactory system are chronically exposed to the ambient environment and may therefore be susceptible to damage from occupational exposure to many volatile chemicals. To investigate whether occupational exposure to styrene was associated with olfactory impairment, we examined olfactory function in 2 groups: workers in a German reinforced-plastics boat-manufacturing facility having a minimum of 2 years of styrene exposure (15-25 ppm as calculated from urinary metabolite concentrations, with historical exposures up to 85 ppm) and a group of age-matched workers from the same facility with lower styrene exposures. The results were also compared with normative data previously collected from healthy, unexposed individuals. Multiple measures of olfactory function were evaluated using a standardized battery of clinical assessments from the Monell-Jefferson Chemosensory Clinical Research Center that included tests of threshold sensitivity for phenylethyl alcohol (PEA) and odor identification ability. Thresholds for styrene were also obtained as a measure of occupational olfactory adaptation. Styrene exposure history was calculated through the use of past biological monitoring results for urinary metabolites of styrene (mandelic acid [MA], phenylglyoxylic acid [PGA]); current exposure was determined for each individual using passive air sampling for styrene and biological monitoring for styrene urinary metabolites. Current mean effective styrene exposure during the day of olfactory testing for the group of workers who worked directly with styrene resins was 18 ppm styrene (standard deviation [SD] = 14), 371 g/g creatinine MA + PGA (SD = 289) and that of the group of workers with lower exposures was 4.8 ppm (SD = 5.2), 93 g/g creatinine MA+PGA (SD = 100). Historic annual average exposures for all workers were greater by a factor of up to 6x. No differences unequivocally attributable to exposure status were observed between the Exposed and

  4. Metabolic consequences of long-term rapamycin exposure on common marmoset monkeys (Callithrix jacchus).

    Science.gov (United States)

    Ross, Corinna; Salmon, Adam; Strong, Randy; Fernandez, Elizabeth; Javors, Marty; Richardson, Arlan; Tardif, Suzette

    2015-11-01

    Rapamycin has been shown to extend lifespan in rodent models, but the effects on metabolic health and function have been widely debated in both clinical and translational trials. Prior to rapamycin being used as a treatment to extend both lifespan and healthspan in the human population, it is vital to assess the side effects of the treatment on metabolic pathways in animal model systems, including a closely related non-human primate model. In this study, we found that long-term treatment of marmoset monkeys with orally-administered encapsulated rapamycin resulted in no overall effects on body weight and only a small decrease in fat mass over the first few months of treatment. Rapamycin treated subjects showed no overall changes in daily activity counts, blood lipids, or significant changes in glucose metabolism including oral glucose tolerance. Adipose tissue displayed no differences in gene expression of metabolic markers following treatment, while liver tissue exhibited suppressed G6Pase activity with increased PCK and GPI activity. Overall, the marmosets revealed only minor metabolic consequences of chronic treatment with rapamycin and this adds to the growing body of literature that suggests that chronic and/or intermittent rapamycin treatment results in improved health span and metabolic functioning. The marmosets offer an interesting alternative animal model for future intervention testing and translational modeling.

  5. Effect of Genetic Polymorphisms and Long-Term Tobacco Exposure on the Risk of Breast Cancer.

    Science.gov (United States)

    Verde, Zoraida; Santiago, Catalina; Chicharro, Luis Miguel; Reinoso-Barbero, Luis; Tejerina, Alejandro; Bandrés, Fernando; Gómez-Gallego, Félix

    2016-10-14

    Tobacco smoke contains many potentially harmful compounds that may act differently and at different stages in breast cancer development. The focus of this work was to assess the possible role of cigarette smoking (status, dose, duration or age at initiation) and polymorphisms in genes coding for enzymes involved in tobacco carcinogen metabolism (CYP1A1, CYP2A6) or in DNA repair (XRCC1, APEX1, XRCC3 and XPD) in breast cancer development. We designed a case control study with 297 patients, 217 histologically verified breast cancers (141 smokers and 76 non-smokers) and 80 healthy smokers in a cohort of Spanish women. We found an association between smoking status and early age at diagnosis of breast cancer. Among smokers, invasive carcinoma subtype incidence increased with intensity and duration of smoking (all Ptrend < 0.05). When smokers were stratified by smoking duration, we only observed differences in long-term smokers, and the CYP1A1 Ile462Ile genotype was associated with increased risk of breast cancer (OR = 7.12 (1.98-25.59)). Our results support the main effect of CYP1A1 in estrogenic metabolism rather than in tobacco carcinogen activation in breast cancer patients and also confirmed the hypothesis that CYP1A1 Ile462Val, in association with long periods of active smoking, could be a breast cancer risk factor.

  6. Effect of Genetic Polymorphisms and Long-Term Tobacco Exposure on the Risk of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Zoraida Verde

    2016-10-01

    Full Text Available Introduction: Tobacco smoke contains many potentially harmful compounds that may act differently and at different stages in breast cancer development. The focus of this work was to assess the possible role of cigarette smoking (status, dose, duration or age at initiation and polymorphisms in genes coding for enzymes involved in tobacco carcinogen metabolism (CYP1A1, CYP2A6 or in DNA repair (XRCC1, APEX1, XRCC3 and XPD in breast cancer development. Methods: We designed a case control study with 297 patients, 217 histologically verified breast cancers (141 smokers and 76 non-smokers and 80 healthy smokers in a cohort of Spanish women. Results: We found an association between smoking status and early age at diagnosis of breast cancer. Among smokers, invasive carcinoma subtype incidence increased with intensity and duration of smoking (all Ptrend < 0.05. When smokers were stratified by smoking duration, we only observed differences in long-term smokers, and the CYP1A1 Ile462Ile genotype was associated with increased risk of breast cancer (OR = 7.12 (1.98–25.59. Conclusions: Our results support the main effect of CYP1A1 in estrogenic metabolism rather than in tobacco carcinogen activation in breast cancer patients and also confirmed the hypothesis that CYP1A1 Ile462Val, in association with long periods of active smoking, could be a breast cancer risk factor.

  7. Long-term exposure to air pollution and mammographic density in the Danish Diet, Cancer and Health cohort

    DEFF Research Database (Denmark)

    Huynh, Stephanie; von Euler-Chelpin, My; Raaschou-Nielsen, Ole

    2015-01-01

    BACKGROUND: Growing evidence suggests that air pollution may be a risk factor for breast cancer, but the biological mechanism remains unknown. High mammographic density (MD) is one of the strongest predictors and biomarkers of breast cancer risk, but it has yet to be linked to air pollution. We...... pollution increases breast cancer risk, it is not via MD....... investigated the association between long-term exposure to traffic-related air pollution and MD in a prospective cohort of women 50 years and older. METHODS: For the 4,769 women (3,930 postmenopausal) participants in the Danish Diet, Cancer and Health cohort (1993-1997) who attended mammographic screening...

  8. Pulmotoxicological effects caused by long-term titanium dioxide nanoparticles exposure in mice

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Qingqing; Tan, Danning; Ze, Yuguan; Sang, Xuezi [Medical College of Soochow University, Suzhou 215123 (China); Liu, Xiaorun [Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009 (China); Jiangsu Key Laboratory for Biomaterials and Devices, Southeast University, Nanjing 210009 (China); Gui, Suxin; Cheng, Zhe; Cheng, Jie; Hu, Renping; Gao, Guodong; Liu, Gan; Zhu, Min; Zhao, Xiaoyang; Sheng, Lei; Wang, Ling [Medical College of Soochow University, Suzhou 215123 (China); Tang, Meng, E-mail: tm@seu.edu.cn [Key Laboratory of Environmental Medicine and Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009 (China); Jiangsu Key Laboratory for Biomaterials and Devices, Southeast University, Nanjing 210009 (China); Hong, Fashui, E-mail: Hongfsh_cn@sina.com [Medical College of Soochow University, Suzhou 215123 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Exposure to TiO{sub 2} NPs could be significantly accumulated in the lung. Black-Right-Pointing-Pointer Exposure to TiO{sub 2} NPs caused pulmonary injury in mice. Black-Right-Pointing-Pointer Exposure to TiO{sub 2} NP promoted the expression of inflammatory cytokines in the lung. Black-Right-Pointing-Pointer Exposure to TiO{sub 2} NP caused ROS overproduction in the lung. - Abstract: Exposure to titanium dioxide nanoparticles (TiO{sub 2} NPs) has been demonstrated to result in pulmonary inflammation in animals; however, very little is known about the molecular mechanisms of pulmonary injury due to TiO{sub 2} NPs exposure. The aim of this study was to evaluate the oxidative stress and molecular mechanism associated with pulmonary inflammation in chronic lung toxicity caused by the intratracheal instillation of TiO{sub 2} NPs for 90 consecutive days in mice. Our findings suggest that TiO{sub 2} NPs are significantly accumulated in the lung, leading to an obvious increase in lung indices, inflammation and bleeding in the lung. Exposure to TiO{sub 2} NPs significantly increased the accumulation of reactive oxygen species and the level of lipid peroxidation, and decreased antioxidant capacity in the lung. Furthermore, TiO{sub 2} NPs exposure activated nuclear factor-{kappa}B, increased the levels of tumor necrosis factor-{alpha}, cyclooxygenase-2, heme oxygenase-1, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, interleukin-18, interleukin-1{beta}, and CYP1A1 expression. However, TiO{sub 2} NPs exposure decreased NF-{kappa}B-inhibiting factor and heat shock protein 70 expression. Our results suggest that the generation of pulmonary inflammation caused by TiO{sub 2} NPs in mice is closely related to oxidative stress and the expression of inflammatory cytokines.

  9. Brief embryonic strychnine exposure in zebrafish causes long-term adult behavioral impairment with indications of embryonic synaptic changes.

    Science.gov (United States)

    Roy, Nicole M; Arpie, Brianna; Lugo, Joseph; Linney, Elwood; Levin, Edward D; Cerutti, Daniel

    2012-01-01

    Zebrafish provide a powerful model of the impacts of embryonic toxicant exposure on neural development that may result in long-term behavioral dysfunction. In this study, zebrafish embryos were treated with 1.5mM strychnine for short embryonic time windows to induce transient changes in inhibitory neural signaling, and were subsequently raised in untreated water until adulthood. PCR analysis showed indications that strychnine exposure altered expression of some genes related to glycinergic, GABAergic and glutamatergic neuronal synapses during embryonic development. In adulthood, treated fish showed significant changes in swimming speed and tank diving behavior compared to controls. Taken together, these data show that a short embryonic exposure to a neurotoxicant can alter development of neural synapses and lead to changes in adult behavior. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Long-term dietary exposure to lead in young European children: Comparing a pan-European approach with a national exposure assessment

    DEFF Research Database (Denmark)

    Boon, P.E.; Te Biesebeek, J.D.; van Klaveren, J.D.

    2012-01-01

    Long-term dietary exposures to lead in young children were calculated by combining food consumption data of 11 European countries categorised using harmonised broad food categories with occurrence data on lead from different Member States (pan-European approach). The results of the assessment...... in children living in the Netherlands were compared with a long-term lead intake assessment in the same group using Dutch lead concentration data and linking the consumption and concentration data at the highest possible level of detail. Exposures obtained with the pan-European approach were higher than...... the national exposure calculations. For both assessments cereals contributed most to the exposure. The lower dietary exposure in the national study was due to the use of lower lead concentrations and a more optimal linkage of food consumption and concentration data. When a pan-European approach, using...

  11. Long-term exposure to political violence: The particular injury of persistent humiliation.

    Science.gov (United States)

    Barber, Brian K; McNeely, Clea; Olsen, Joseph A; Belli, Robert F; Doty, Samuel Benjamin

    2016-05-01

    This study assessed the association between exposure to political violence over a 25-year period and adult functioning among a population that has experienced protracted and severe political conflict. Instead of aggregating exposure to political violence across time and type of exposure, as is commonly done, the event history calendar pioneered in this study assessed exposure to five forms of political violence annually from 1987 to 2011 in a representative sample of 1788 adults, aged 37 on average, in the occupied Palestinian territories (West Bank, East Jerusalem, and the Gaza Strip). This method allowed for the identification of trajectories of exposure to political violence from childhood to adulthood using latent profile analysis. We then correlated the trajectories of exposure to measures of economic, political, community, family, psychological, and health functioning. As expected, being shot at, having one's home raided, being hit or kicked, being verbally abused, and witnessing someone close being humiliated were all elevated during periods of heightened political conflict (the first intifada (1987-1993) and, less so, the second intifada (2000-2005)). In addition, 12% of women and men reported high and persistent levels of exposure to humiliation (being verbally abused and/or witnessing someone close being humiliated) across the entire 25-year period. These individuals lived predominantly in neighborhoods with a high Israeli military presence. Compared to those who experienced periodic exposure to political violence, persistently humiliated men and women reported significantly lower health, economic, political, and psychological functioning, as well as higher social cohesion and political expression. Relevant literatures are reviewed when concluding that persistent humiliation is a neglected form of political violence that is best represented as a direct (versus structural), acute (versus chronic), macro (versus micro), and high-grade (versus low

  12. Multiple procedures and cumulative individual radiation exposure in interventional cardiology: A long-term retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Weltermann, Birgitta M.; Rock, Thomas; Berndt, Peter; Viehmann, Anja; Reinders, Sabrina; Gesenhues, Stefan [University of Duisburg-Essen, Institute for General Medicine, University Hospital, Essen (Germany); Brix, Gunnar; Schegerer, Alexander [Federal Office for Radiation Protection, Department of Radiation Protection and Health, Neuherberg (Germany)

    2015-09-15

    Various studies address discrepancies between guideline recommendations for coronary angiographies and clinical practice. While the issue of the appropriateness of recurrent angiographies was studied focusing on the role of the cardiologist, little is known about individual patients' histories and the associated radiation exposures. We analyzed all patients with coronary artery disease (CAD) in an academic teaching practice who underwent at least one angiography with or without intervention between 2004 and 2009. All performed angiographies in these patients were analyzed and rated by three physicians for appropriateness levels according to cardiology guidelines. Typical exposure data from the medical literature were used to estimate individual radiation exposure. In the cohort of 147 patients, a total of 441 procedures were analyzed: between 1981 and 2009, three procedures were performed per patient (range 1-19) on average. Appropriateness ratings were 'high/intermediate' in 71 %, 'low/no' in 27.6 % and data were insufficient for ratings in 1.4 %. Procedures with 'low/no' ratings were associated with potentially avoidable exposures of up to 186 mSv for single patients. Using retrospective data, we exemplify the potential benefit of guideline adherence to decrease patients' radiation exposures. (orig.)

  13. Exposure to magnetic fields and long term survival among children having a leukemia; Exposition aux champs magnetiques et survie a long terme chez les enfants ayant une leucemie

    Energy Technology Data Exchange (ETDEWEB)

    Souques, M

    2006-09-15

    A study, the first one, bearing on the survival of children reached by acute lymphoblastic leukemia finds an association between mortality and the highest class of exposure ( over .3 {mu}T). The authors relativize the level of their results because the study has been made on a small number of cases, this illness staying rare. However, the relapse rate is not increased in a significant way for the children of the highest exposure category. (N.C.)

  14. [Interaction between benzene and toluene in long term inhalation exposure in rats (author's transl)].

    Science.gov (United States)

    Gradiski, D; Bonnet, P; Duprat, P; Zissu, D; Magadur, J L; Guenier, J P

    1981-07-01

    Industrial chemicals are seldom used as pure substances; hazards resulting from exposure to mixtures have, however not been solved. Our study deals with chronic inhalation toxicity of a mixture of benzene and toluene; few studies have been completed on this subject. Our results show: - leucopenia with benzene alone, at a concentration of 50 p.p.m., that is not detectable in the presence of toluene; - metabolic variations consisting in: a decrease in the phenol urinary rate versus time with benzene alone; a sharp decrease of this rate from the third month of exposure on, in presence of toluene.

  15. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

    Science.gov (United States)

    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.

  16. Short and long term consequences of larval stage exposure to constantly and ephemerally elevated carbon dioxide for marine bivalve populations

    Directory of Open Access Journals (Sweden)

    C. J. Gobler

    2012-11-01

    Full Text Available While larval bivalves are highly sensitive to ocean acidification, the basis for this sensitivity and the longer term implications of this sensitivity are unclear. Experiments were performed to assess the short term (days and long term (months consequences of larval stage exposure to varying CO2 concentrations for calcifying bivalves. Higher CO2 concentrations depressed both calcification rates assessed using 45Ca uptake and RNA:DNA ratios in Mercenaria mercenaria and Argopecten irradians larvae with RNA:DNA ratios being highly correlated with larval growth rates r2 > 0.9. These findings suggested that high CO2 has a cascading negative physiological impact on bivalve larvae stemming in part from lower calcification rates. Exposure to elevated CO2 during the first four days of larval development significantly depressed A. irradians larval survival rates, while a 10 day exposure later in larval development did not, demonstrating the extreme CO2-sensitivity of bivalve larvae during first days of development. Short- (weeks and long-term (10 month experiments revealed that individuals surviving exposure to high CO2 during larval development grew faster when exposed to normal CO2 as juveniles compared to individuals reared under ambient CO2 as larvae. These increased growth rates could not, however, overcome size differences established during larval development, as size deficits of individuals exposed to even moderate levels of CO2 as larvae were evident even after 10 months of growth under normal CO2 concentrations. This `legacy effect' emphasizes the central role larval stage CO2 exposure can play in shaping the success of modern day bivalve populations.

  17. Determining prenatal, early childhood and cumulative long-term lead exposure using micro-spatial deciduous dentine levels.

    Directory of Open Access Journals (Sweden)

    Manish Arora

    Full Text Available The aim of this study was to assess the validity of micro-spatial dentine lead (Pb levels as a biomarker for accurately estimating exposure timing over the prenatal and early childhood periods and long-term cumulative exposure to Pb. In a prospective pregnancy cohort sub-sample of 85 subjects, we compared dentine Pb levels measured using laser ablation-inductively coupled plasma mass spectrometry with Pb concentrations in maternal blood collected in the second and third trimesters, maternal bone, umbilical cord blood, and childhood serial blood samples collected from the ages of 3 months to ≥6 years. We found that Pb levels (as 208Pb:43Ca in dentine formed at birth were significantly associated with cord blood Pb (Spearman ρ = 0.69; n = 27; p<0.0001. The association of prenatal dentine Pb with maternal patella Pb (Spearman ρ = 0.48; n = 59; p<0.0001 was stronger than that observed for tibia Pb levels (Spearman ρ = 0.35; n = 41; p<0.03. When assessing postnatal exposure, we found that Pb levels in dentine formed at 3 months were significantly associated with Pb concentrations in children's blood collected concurrently (Spearman ρ = 0.64; n = 55; p<0.0001. We also found that mean Pb concentrations in secondary dentine (that is formed from root completion to tooth shedding correlated positively with cumulative blood lead index (Spearman ρ = 0.38; n = 75; p<0.0007. Overall, our results support that micro-spatial measurements of Pb in dentine can be reliably used to reconstruct Pb exposure timing over the prenatal and early childhood periods, and secondary dentine holds the potential to estimate long-term exposure up to the time the tooth is shed.

  18. Long-term correlation of the electrocorticogram as a bioindicator of brain exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, L.A.A.; Nogueira, R.A. [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Departamento de Morfologia e Fisiologia Animal. Lab. de Biofisica Teorico-Experimental e Computacional; Silva, I.M.S.; Fernandes, T.S., E-mail: ran.pe@terra.com.br [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Departamento de Biofisica e Radiobiologia

    2015-10-15

    Understanding the effects of radiation and its possible influence on the nervous system are of great clinical interest. However, there have been few electrophysiological studies on brain activity after exposure to ionizing radiation (IR). A new methodological approach regarding the assessment of the possible effects of IR on brain activity is the use of linear and nonlinear mathematical methods in the analysis of complex time series, such as brain oscillations measured using the electrocorticogram (ECoG). The objective of this study was to use linear and nonlinear mathematical methods as biomarkers of gamma radiation regarding cortical electrical activity. Adult Wistar rats were divided into 3 groups: 1 control and 2 irradiated groups, evaluated at 24 h (IR24) and 90 days (IR90) after exposure to 18 Gy of gamma radiation from a cobalt-60 radiotherapy source. The ECoG was analyzed using power spectrum methods for the calculation of the power of delta, theta, alpha and beta rhythms and by means of the a-exponent of the detrended fluctuation analysis (DFA). Using both mathematical methods it was possible to identify changes in the ECoG, and to identify significant changes in the pattern of the recording at 24 h after irradiation. Some of these changes were persistent at 90 days after exposure to IR. In particular, the theta wave using the two methods showed higher sensitivity than other waves, suggesting that it is a possible biomarker of exposure to IR. (author)

  19. Long-term correlation of the electrocorticogram as a bioindicator of brain exposure to ionizing radiation

    Directory of Open Access Journals (Sweden)

    L.A.A. Aguiar

    2015-01-01

    Full Text Available Understanding the effects of radiation and its possible influence on the nervous system are of great clinical interest. However, there have been few electrophysiological studies on brain activity after exposure to ionizing radiation (IR. A new methodological approach regarding the assessment of the possible effects of IR on brain activity is the use of linear and nonlinear mathematical methods in the analysis of complex time series, such as brain oscillations measured using the electrocorticogram (ECoG. The objective of this study was to use linear and nonlinear mathematical methods as biomarkers of gamma radiation regarding cortical electrical activity. Adult Wistar rats were divided into 3 groups: 1 control and 2 irradiated groups, evaluated at 24 h (IR24 and 90 days (IR90 after exposure to 18 Gy of gamma radiation from a cobalt-60 radiotherapy source. The ECoG was analyzed using power spectrum methods for the calculation of the power of delta, theta, alpha and beta rhythms and by means of the α-exponent of the detrended fluctuation analysis (DFA. Using both mathematical methods it was possible to identify changes in the ECoG, and to identify significant changes in the pattern of the recording at 24 h after irradiation. Some of these changes were persistent at 90 days after exposure to IR. In particular, the theta wave using the two methods showed higher sensitivity than other waves, suggesting that it is a possible biomarker of exposure to IR.

  20. Long-term exposure to a ‘safe’ dose of bisphenol A reduced protein acetylation in adult rat testes

    Science.gov (United States)

    Chen, Zhuo; Zuo, Xuezhi; He, Dongliang; Ding, Shibin; Xu, Fangyi; Yang, Huiqin; Jin, Xin; Fan, Ying; Ying, Li; Tian, Chong; Ying, Chenjiang

    2017-01-01

    Bisphenol A (BPA), a typical environmental endocrine-disrupting chemical, induces epigenetic inheritance. Whether histone acetylation plays a role in these effects of BPA is largely unknown. Here, we investigated histone acetylation in male rats after long-term exposure to a ‘safe’ dose of BPA. Twenty adult male rats received either BPA (50 μg/kg·bw/day) or a vehicle diet for 35 weeks. Decreased protein lysine-acetylation levels at approximately ~17 kDa and ~25 kDa, as well as decreased histone acetylation of H3K9, H3K27 and H4K12, were detected by Western blot analysis of testes from the treated rats compared with controls. Additionally, increased protein expression of deacetylase Sirt1 and reduced binding of Sirt1, together with increased binding of estrogen receptor β (ERβ) to caveolin-1 (Cav-1), a structural protein component of caveolar membranes, were detected in treated rats compared with controls. Moreover, decreased acetylation of Cav-1 was observed in the treated rats for the first time. Our study showed that long-term exposure to a ‘safe’ dose of BPA reduces histone acetylation in the male reproductive system, which may be related to the phenotypic paternal-to-offspring transmission observed in our previous study. The evidence also suggested that these epigenetic effects may be meditated by Sirt1 via competition with ERβ for binding to Cav-1.

  1. Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans.

    Science.gov (United States)

    Shahin-Jafari, Ariyo; Bayat, Mansour; Shahhosseiny, Mohammad Hassan; Tajik, Parviz; Roudbar-Mohammadi, Shahla

    2016-05-01

    Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were exposed at 4 °C to a fixed magnitude of radiation with different time periods of 10, 70, 210, 350 and 490 h. The other 5 tubes were kept far enough from radiation. The samples underwent genomic DNA extraction. PCR amplification of alpha-Int1 gene sequence was done using one set of primers. PCR products were resolved using agarose gel electrophoresis and the nucleotide sequences were determined. All samples showed a clear electrophoretic band around 441 bp and further sequencing revealed the amplified DNA segments are related to alpha-Int1 gene of the yeast. No mutations in the gene were seen in radiation exposed samples. Long-term exposure of the yeast to mobile phone radiation under the above mentioned conditions had no mutagenic effect on alpha-Int1 gene sequence.

  2. Differential effects of long-term exposure to Aroclor 1254 on lipid secretion by primary cultures of adult rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza-Figueroa, T.; Hernandez, A.; Lopez, L. [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (Mexico)

    1992-06-01

    PCBs produce hepatic triglyceride (TG) accumulation (fatty liver) in experimental animals and humans exposed accidentally and occupationally. It has been suggested that this effect could be due to a block in TG secretion. On the other hand, increased levels of plasmatic TG and cholesterol have been described in rats after dietary exposure to Aroclor 1254 (Aro) and other PCBs; hypertriglyceridemia and hypertension have been also described in humans exposed for long periods to low concentrations of PCBs. Since the study of hepatic lipid metabolism and its alteration by toxic chemicals is complicated in the whole animal, short term cultures of adult rat hepatocytes have been used. We have described a system for the long term culture of adult rat hepatocytes which for several weeks maintain differentiated functions, like fatty acid and TG synthesis and their export to the culture medium. In this paper we used this culture system to study the effect of long-term exposure to micromolar concentrations of Aro on the secretion of lipids by cultured hepatocytes. 27 refs., 4 figs., 1 tab.

  3. Oxidative Stress and Genotoxicity of Long-Term Occupational Exposure to Low Levels of BTEX in Gas Station Workers

    Directory of Open Access Journals (Sweden)

    Feng Xiong

    2016-12-01

    Full Text Available Atmospheric benzene, toluene, ethylbenzene, and xylenes (BTEX can lead to multiple health injuries. However, what remains uncertain is the effect of long-term exposure to low levels of BTEX. Thus, we determined the BTEX levels in the air from the refueling and office areas in gas stations. Then we collected workers’ (200 refueling vs. 52 office workers peripheral blood samples to analyze the serum total-superoxide dismutase (T-SOD, glutathione (GSH, malondialdehyde (MDA, and 8-hydroxydeoxyguanosine (8-OHdG levels. DNA damage was analyzed by the comet assay and micronucleus test in buccal epithelial cells. We found that the levels of BTEX in refueling areas were significantly higher than those in office areas (p < 0.001. The serum T-SOD and GSH of refueling workers were significantly lower than those in office workers (p < 0.001. By contrast, the serum MDA and 8-OHdG of refueling workers were significantly higher than those of office workers (p < 0.001, MDA; p = 0.025, 8-OHdG. Furthermore, tail and Olive tail moments in refueling workers were longer (p = 0.004, tail moment; p = 0.001, Olive tail moment, and the micronucleus rate was higher (p < 0.001 than those in office workers. Taken together, long-term exposure to low levels of BTEX may reduce the antioxidant ability and increase the risk of DNA damage in refueling workers of gas stations.

  4. Diethyl phosphates accumulation in rabbits' hair as an indicator of long term exposure to diazinon and chlorpyrifos.

    Science.gov (United States)

    Maravgakis, George; Tzatzarakis, Manolis N; Alegakis, Athanasios K; Stivaktakis, Polychronis D; Tsatsakis, Aristidis M

    2012-05-10

    Long term exposure to organophosphate pesticides can be evaluated by quantitative analysis of their non-specific metabolites in hair matrix. The aim of this study was to determine whether these metabolites can be internally incorporated into the hair of rabbits exposed to diazinon and chlorpyrifos. The influence of dose and dose duration of each pesticide dosage were investigated. Three groups of rabbits were exposed to different dosages of diazinon (3.0 and 6.0mg/kg/day) and chlorpyrifos (18.0mg/kg/day) via drinking water. Hair samples were collected every month and analyzed for diethyl phosphate (DEP) and diethyl thiophosphate (DETP) by gas chromatography-mass spectrometry (GC-MS). The mean concentrations of the low-dose treated group, ranged from 112 to 257pg/mg for DEP and from 295 to 515pg/mg for DETP in hair. The high-dose treated group demonstrated a range of mean concentrations from 142 to 585pg/mg for DEP and from 406 to 988pg/mg for DETP in hair. For the chlorpyrifos treated group, the concentrations ranged from 138 to 1070 for DEP and from 554 to 886pg/mg for DETP. Analysis revealed the incorporation of these metabolites into the rabbit hair in a dosage and dose duration-dependent manner. These data confirms the ability of using hair analysis for diethyl phosphates to assess long-term OP exposure.

  5. Long-Term Exposure to American and European Movies and Television Series Facilitates Caucasian Face Perception in Young Chinese Watchers.

    Science.gov (United States)

    Wang, Yamin; Zhou, Lu

    2016-10-01

    Most young Chinese people now learn about Caucasian individuals via media, especially American and European movies and television series (AEMT). The current study aimed to explore whether long-term exposure to AEMT facilitates Caucasian face perception in young Chinese watchers. Before the experiment, we created Chinese, Caucasian, and generic average faces (generic average face was created from both Chinese and Caucasian faces) and tested participants' ability to identify them. In the experiment, we asked AEMT watchers and Chinese movie and television series (CMT) watchers to complete a facial norm detection task. This task was developed recently to detect norms used in facial perception. The results indicated that AEMT watchers coded Caucasian faces relative to a Caucasian face norm better than they did to a generic face norm, whereas no such difference was found among CMT watchers. All watchers coded Chinese faces by referencing a Chinese norm better than they did relative to a generic norm. The results suggested that long-term exposure to AEMT has the same effect as daily other-race face contact in shaping facial perception.

  6. Long-term exposure to a ‘safe’ dose of bisphenol A reduced protein acetylation in adult rat testes

    Science.gov (United States)

    Chen, Zhuo; Zuo, Xuezhi; He, Dongliang; Ding, Shibin; Xu, Fangyi; Yang, Huiqin; Jin, Xin; Fan, Ying; Ying, Li; Tian, Chong; Ying, Chenjiang

    2017-01-01

    Bisphenol A (BPA), a typical environmental endocrine-disrupting chemical, induces epigenetic inheritance. Whether histone acetylation plays a role in these effects of BPA is largely unknown. Here, we investigated histone acetylation in male rats after long-term exposure to a ‘safe’ dose of BPA. Twenty adult male rats received either BPA (50 μg/kg·bw/day) or a vehicle diet for 35 weeks. Decreased protein lysine-acetylation levels at approximately ~17 kDa and ~25 kDa, as well as decreased histone acetylation of H3K9, H3K27 and H4K12, were detected by Western blot analysis of testes from the treated rats compared with controls. Additionally, increased protein expression of deacetylase Sirt1 and reduced binding of Sirt1, together with increased binding of estrogen receptor β (ERβ) to caveolin-1 (Cav-1), a structural protein component of caveolar membranes, were detected in treated rats compared with controls. Moreover, decreased acetylation of Cav-1 was observed in the treated rats for the first time. Our study showed that long-term exposure to a ‘safe’ dose of BPA reduces histone acetylation in the male reproductive system, which may be related to the phenotypic paternal-to-offspring transmission observed in our previous study. The evidence also suggested that these epigenetic effects may be meditated by Sirt1 via competition with ERβ for binding to Cav-1. PMID:28067316

  7. Impact of long-term thermal exposure on a SiC fiber-reinforced copper matrix composite

    Energy Technology Data Exchange (ETDEWEB)

    Kimmig, S.; Elgeti, S.; You, Jeong-Ha, E-mail: you@ipp.mpg.de

    2013-11-15

    Silicon carbide long fiber-reinforced copper matrix composites offer huge potential as a heat sink material of divertor for applications at temperatures above 300 °C thanks to the beneficial combination of strong ceramic fibers and highly conductive copper. For applications at higher operation temperatures, long term thermal stability is an issue, as thermal exposure may cause a detrimental change in microstructure in terms of chemistry and integrity of the constituents leading to overall deterioration of composite strength. The aim of this study is to investigate the impact of long term thermal exposure at an elevated temperature on a Cu/SiC{sub f} composite material. To this end, composite samples were fabricated and subjected to a heat treatment at 550 °C for 400 h. Extensive tensile tests were conducted for a wide range of fibers volume fractions to evaluate the strength before and after the heat treatment. Acoustic emission was detected in situ during tensile tests for tracking the failure events. Microscopic analysis was carried out to capture the chemical change and damage. It turned out that the applied heat treatment caused significant reduction of strength. Microanalysis revealed that infiltration and diffusion of copper into the fibers via the cracks of the damaged fibers are the direct cause of the embrittlement.

  8. Impact of long-term thermal exposure on a SiC fiber-reinforced copper matrix composite

    Science.gov (United States)

    Kimmig, S.; Elgeti, S.; You, Jeong-Ha

    2013-11-01

    Silicon carbide long fiber-reinforced copper matrix composites offer huge potential as a heat sink material of divertor for applications at temperatures above 300 °C thanks to the beneficial combination of strong ceramic fibers and highly conductive copper. For applications at higher operation temperatures, long term thermal stability is an issue, as thermal exposure may cause a detrimental change in microstructure in terms of chemistry and integrity of the constituents leading to overall deterioration of composite strength. The aim of this study is to investigate the impact of long term thermal exposure at an elevated temperature on a Cu/SiCf composite material. To this end, composite samples were fabricated and subjected to a heat treatment at 550 °C for 400 h. Extensive tensile tests were conducted for a wide range of fibers volume fractions to evaluate the strength before and after the heat treatment. Acoustic emission was detected in situ during tensile tests for tracking the failure events. Microscopic analysis was carried out to capture the chemical change and damage. It turned out that the applied heat treatment caused significant reduction of strength. Microanalysis revealed that infiltration and diffusion of copper into the fibers via the cracks of the damaged fibers are the direct cause of the embrittlement.

  9. Enhancement of hydrogen isotope retention capacity for the impurity deposited tungsten by long-term plasma exposure in LHD

    Energy Technology Data Exchange (ETDEWEB)

    Oya, Yasuhisa, E-mail: syoya@ipc.shizuoka.ac.jp [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka 422-8529 (Japan); Masuzaki, Suguru; Tokitani, Masayuki [National Institute for Fusion Science, Gifu 509-5292 (Japan); Yoshida, Naoaki; Watanabe, Hideo [Kyushu University, Fukuoka 816-8580 (Japan); Yamauchi, Yuji; Hino, Tomoaki [Hokkaido University, Sapporo 060-8628 (Japan); Miyamoto, Mitsutaka [Shimane University, Shimane 690-8504 (Japan); Hatano, Yuji [University of Toyama, Toyama 930-8555 (Japan); Okuno, Kenji [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka 422-8529 (Japan)

    2013-10-15

    Highlights: • The carbon-dominant mixed-material layer was formed on the tungsten surface after 15{sup th} plasma exposure in LHD. • The largest enhancement of deuterium retention was found to be about 21. • The major deuterium desorption temperature was shifted toward higher temperature side. -- Abstract: The stress relieved tungsten samples were placed at three positions, PI (sputtering erosion dominated area), DP (deposition dominated area) and HL (Higher heat load area) during 15th plasma experiment campaign in Large Helical Device (LHD) at National Institute for Fusion Science (NIFS), Japan and were exposed to ∼ 6700 shots of hydrogen plasma in a 15th long-term experiment campaign in LHD. Thereafter, the additional deuterium ion implantation to these tungsten samples was performed to evaluate the change of hydrogen isotope retention capacity in the samples by long-term plasma exposure. It was found that the carbon-dominant mixed-material layer with more than 100 nm thickness was formed on a wide area of the tungsten surface. The thicker mixed-material layer was formed on the DP sample, where the deuterium retention was about 21 times as high as that for pure W. The major desorption temperature of deuterium was shifted toward higher temperature side, which was comparable to the trapping characteristic of carbon or irradiation damages.

  10. Inhibition of anaerobic wastewater treatment after long-term exposure to low levels of CuO nanoparticles.

    Science.gov (United States)

    Otero-González, Lila; Field, Jim A; Sierra-Alvarez, Reyes

    2014-07-01

    CuO nanoparticles (NPs) are released into wastewater due to the widespread use and generation as by-product in various applications (e.g. semiconductor manufacturing). However, information on the behavior and impact of CuO NPs on wastewater treatment processes is very limited. The objective of this study was to evaluate the fate and long-term effect of CuO NPs (average size = 37 nm) on high-rate anaerobic bioreactors. A laboratory-scale upflow anaerobic sludge blanket reactor was operated with a synthetic wastewater containing low concentrations of CuO NPs (1.4 mg Cu L(-1)) and a mixture of volatile fatty acids for 107 days. CuO NPs were largely removed during anaerobic treatment and on the average only 20-32% of the NPs fed to the reactor escaped with the effluent. Scanning electron microscopy and chemical analysis confirmed that CuO NPs were partitioned into the anaerobic sludge. While short-term exposure to CuO NPs (1.4 mg Cu L(-1)) only caused minor inhibition to methanogenesis, extended exposure caused severe toxicity and reduced the acetoclastic methanogenic activity by more than 85%. Moreover, the reactor performance was completely disrupted and the methane production decreased by more than 50%. The study is the first to demonstrate a significant long-term effect of low levels of CuO NPs on methanogenesis.

  11. Comparison of models for estimation of long-term exposure to air pollution in cohort studies

    Science.gov (United States)

    Beverland, I. J.; Robertson, C.; Yap, C.; Heal, M. R.; Cohen, G. R.; Henderson, D. E. J.; Hart, C. L.; Agius, R. M.

    2012-12-01

    This study compared three spatio-temporal models for estimation of exposure to air pollution throughout the central part of Scotland during 1970-79 for approximately 21,600 individuals in 2 closely-related prospective cohort studies. Although 181 black smoke (BS) monitoring sites operated in this region at some point during 1970-79, a substantial amount of BS exposure data was missing at many sites. The three exposure estimation methods were: (i) area-based regression models to impute missing data followed by assignment of exposure by inverse distance weighting of observed BS at nearby monitoring sites (IDWBS); (ii) area-based regression models to impute missing data followed by a spatial regression additive model using four local air quality predictors (LAQP): altitude; distance to the nearest major road; household density within a 250 m buffer zone; and distance to the edge of urban boundary (AMBS); (iii) a multilevel spatio-temporal model using LAQP (MultiBS). The three methods were evaluated using maps of predicted BS, and cross validation using monitored and imputed BS at sites with ≥80% data. The use of LAQP in the AMBS and MultiBS exposure models provided spatial patterns in BS consistent with known sources of BS associated with major roads and the centre of urban areas. Cross-validation analyses demonstrated that the MultiBS model provided more precise predictions (R2 = 60%) of decadal geometric mean BS concentrations at monitoring sites compared with the IDWBS and AMBS models (R2 of 19% and 20%, respectively).

  12. Does respiratory health contribute to the effects of long-term air pollution exposure on cardiovascular mortality?

    Directory of Open Access Journals (Sweden)

    Heinrich Joachim

    2007-03-01

    Full Text Available Abstract Background There is growing epidemiological evidence that short-term and long-term exposure to high levels of air pollution may increase cardiovascular morbidity and mortality. In addition, epidemiological studies have shown an association between air pollution exposure and respiratory health. To what extent the association between cardiovascular mortality and air pollution is driven by the impact of air pollution on respiratory health is unknown. The aim of this study was to investigate whether respiratory health at baseline contributes to the effects of long-term exposure to high levels of air pollution on cardiovascular mortality in a cohort of elderly women. Method We analyzed data from 4750 women, aged 55 at the baseline investigation in the years 1985–1994. 2593 of these women had their lung function tested by spirometry. Respiratory diseases and symptoms were asked by questionnaire. Ambient air pollution exposure was assessed by the concentrations of NO2 and total suspended particles at fixed monitoring sites and by the distance of residency to a major road. A mortality follow-up of these women was conducted between 2001 and 2003. For the statistical analysis, Cox' regression was used. Results Women with impaired lung function or pre-existing respiratory diseases had a higher risk of dying from cardiovascular causes. The impact of impaired lung function declined over time. The risk ratio (RR of women with forced expiratory volume in one second (FEV1 of less than 80% predicted to die from cardiovascular causes was RR = 3.79 (95%CI: 1.64–8.74 at 5 years survival time and RR = 1.35 (95%CI: 0.66–2.77 at 12 years. The association between air pollution levels and cardiovascular death rate was strong and statistically significant. However, this association did only change marginally when including indicators of respiratory health into the regression analysis. Furthermore, no interaction between air pollution and respiratory health

  13. [Alteration of thyroid hormone secretion after long-term exposure to low doses of endocrine disruptor DDT].

    Science.gov (United States)

    Iaglova, N V; Iaglov, V V

    2014-01-01

    Endocrine disruptors are exogenous substances that exhibit hormone-like action and consequently disrupt homeostatic action of endogenous hormones. DDT is the most common disruptor. The objective was to evaluate changes in thyroid hormone secretion after long-term exposure to low doses of DDT. The experiment was performed on male Wistar rats. The rats were given DDT at doses of 1.89±0.86 мg/kg/day and 7.77±0.17 мg/kg/day for 6 and 10 weeks. Dose dependent increase of serum total thyroxine, total triiodthyronine, and thyroid peroxidase was revealed after 6 weeks exposure. After 10 weeks free thyroxine secretion was reduced. Such alterations of the thyroid status are typical for iodine deficient goiter. The data obtained indicate that the main mechanism of DDT action includes disruption of thyroxine secretion by thyrocytes, but not inhibition of deiodinase activity and decrease of blood thyroid binding proteins.

  14. Behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic modules under outdoor long term exposure.

    Science.gov (United States)

    Kichou, Sofiane; Silvestre, Santiago; Nofuentes, Gustavo; Torres-Ramírez, Miguel; Chouder, Aissa; Guasch, Daniel

    2016-06-01

    Four years׳ behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic (PV) modules installed in a relatively dry and sunny inland site with a Continental-Mediterranean climate (in the city of Jaén, Spain) are presented in this article. The shared data contributes to clarify how the Light Induced Degradation (LID) impacts the output power generated by the PV array, especially in the first days of exposure under outdoor conditions. Furthermore, a valuable methodology is provided in this data article permitting the assessment of the degradation rate and the stabilization period of the PV modules. Further discussions and interpretations concerning the data shared in this article can be found in the research paper "Characterization of degradation and evaluation of model parameters of amorphous silicon photovoltaic modules under outdoor long term exposure" (Kichou et al., 2016) [1].

  15. Long-term allergen exposure induces adipose tissue inflammation and circulatory system injury.

    Science.gov (United States)

    Jung, Chien-Cheng; Su, Huey-Jen

    2016-05-01

    The purpose of this study was to study whether allergen exposure can induce inflammation and lower the anti-inflammation levels in serum and in adipose tissues, and further develop cardiovascular injury. Our data showed that heart rate was significantly higher in the OVA-challenged mice compared to control mice. Moreover, there were higher expressions of pro-inflammation genes in the OVA-challenged mice in adipose tissues, and the expressions of anti-inflammation genes were lower. The levels of inflammation mediators were associated in serum and adipose tissues. The level of circulatory injury lactate dehydrogenase was significantly associated with the levels of E-selectin, resistin and adiponectin in the serum. The hematoxylin and eosin and immunohistochemistry stains indicated the OVA-challenged mice had higher levels of inflammation. In summary, the current study demonstrated allergen exposure can cause cardiovascular injury, and inflammatory mediators in adipose tissues play an important role in the pathogenesis of cardiovascular injury.

  16. Adsorption, uptake and distribution of gold nanoparticles in Daphnia magna following long term exposure.

    Science.gov (United States)

    Botha, Tarryn Lee; Boodhia, Kailen; Wepener, Victor

    2016-01-01

    Gold nanoparticles (nAu) have recently been studied and developed within the biological and photothermal therapeutic contexts. The major clinical interest is within the application of novel drug delivery systems. Environmental exposure to nanoparticles can occur in different stages of the lifecycle of the product; from their synthesis, applications, product weathering and their disposal. Freshwater Daphnids, specifically Daphnia magna, have been used since the 1960s as a standard species in acute and chronic aquatic toxicity testing. Visualization of the interactions and uptake of nAu by D. magna was related to reproduction and molting patterns. Exposure to nAu was done using a chronic reproduction test performed for 14 days at six concentrations (0.5mg/L, 2mg/L, 5mg/L, 10mg/L, 15mg/L and 20mg/L). Microscopy was used to determine whether there was any uptake or interaction of nAu with daphnia. However the concentration of nAu in the media and the charge of particles played a role in the uptake and surface adsorption. As exposure concentrations of nAu increased it appeared that the nAu aggregated onto the surface and in the gut of the organisms in higher concentrations. There was no evidence of nAu internalization into the body cavity of the daphnia. Aquatic exposure to nAu resulted in increased adhesion of the particles to the carapace of daphnia, ingestion and uptake into the gut of daphnia and had no significant effect on reproduction and molting patterns. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Effects of 4-ter-Octylphenol on Xenopus tropicalis in a Long Term Exposure

    Science.gov (United States)

    2011-03-17

    tubules of control animals were lined with spermatocysts containing spermatogonia, spermatocytes and spermatids at various stages of spermatogenesis ...sloughing was seen in 1 µg/L and 36 µg/LOP exposed frogs, indicating that OP exposure may be disrupting spermatogenesis , but is not sufficient to reduce...disrupts spermatogenesis in Xenopus laevis frogs. Toxicol.Sci 84, 394-407. Lei, B., Huang, S., Zhou, Y., Wang, D., and Wang, Z., 2009. Levels of six

  18. Long-Term Evolution Electromagnetic Fields Exposure Modulates the Resting State EEG on Alpha and Beta Bands.

    Science.gov (United States)

    Yang, Lei; Chen, Qinghua; Lv, Bin; Wu, Tongning

    2016-04-25

    Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.

  19. Long-term changes in amphetamine-induced reinforcement and aversion in rats following exposure to 56Fe particle

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.

    Exposing rats to heavy particles produces alterations in the functioning of dopaminergic neurons and in the behaviors that depend upon the integrity of the dopaminergic system. Two of these dopamine-dependent behaviors include amphetamine-induced reinforcement, measure using the conditioned place preference procedure, and amphetamine-induced reinforcement, measured using the conditioned place preference procedure, and amphetamine-induced aversion, measured using the conditioned taste aversion. Previous research has shown that exposing rats to 1.0 Gy of 1GeV/n 56Fe particles produced a disruption of an amphetamine-induced taste aversion 3 days following exposure, but produced an apparent enhancement of the aversion 112 days following exposure. The present experiments were designed to provide a further evaluation of these results by examining taste aversion learning 154 days following exposure to 1.0Gy 56Fe particles and to establish the convergent validity of the taste aversion results by looking at the effects of exposure on the establishment of an amphetamine-induced conditioned place preference 3, 7, and 16 weeks following irradiation. The taste aversion results failed to confirm the apparent enhancement of the amphetamine-induced CTA observed in the prior experiment. However, exposure to 56Fe particles prevented the acquisition of amphetamine-induced place preference at all three-time intervals. The results are interpreted as indicating that exposure to heavy particles can produce long-term changes in behavioral functioning.

  20. Histopathological examinations of rat brains after long-term exposure to GSM-900 mobile phone radiation.

    Science.gov (United States)

    Grafström, Gustav; Nittby, Henrietta; Brun, Arne; Malmgren, Lars; Persson, Bertil R R; Salford, Leif G; Eberhardt, Jacob

    2008-11-25

    In order to mimic the real life situation, with often life-long exposure to the electromagnetic fields emitted by mobile phones, we have investigated in a rat model the effects of repeated exposures under a long period to Global System for Mobile Communication-900 MHz (GSM-900) radiation. Out of a total of 56 rats, 32 were exposed once weekly in a 2-h period, for totally 55 weeks, at different average whole-body specific absorption rates (SAR) (of in average 0.6 and 60 mW/kg at the initiation of the experimental period). The animals were exposed in a transverse electromagnetic transmission line chamber (TEM-cell) to radiation emitted by a GSM-900 test phone. Sixteen animals were sham exposed and eight animals were cage controls, which never left the animal house. After behavioural tests, 5-7 weeks after the last exposure, the brains were evaluated for histopathological alterations such as albumin extravasation, dark neurons, lipofuscin aggregation and signs of cytoskeletal and neuritic neuronal changes of the type seen in human ageing. In this study, no significant alteration of any these histopathological parameters was found, when comparing the GSM exposed animals to the sham exposed controls.

  1. Mars Radiation Risk Assessment and Shielding Design for Long-term Exposure to Ionizing Space Radiation

    Science.gov (United States)

    Tripathi, Ram K.; Nealy, John E.

    2007-01-01

    NASA is now focused on the agency's vision for space exploration encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. As a result, there is a focus on long duration space missions. NASA is committed to the safety of the missions and the crew, and there is an overwhelming emphasis on the reliability issues for space missions and the habitat. The cost-effective design of the spacecraft demands a very stringent requirement on the optimization process. Exposure from the hazards of severe space radiation in deep space and/or long duration missions is a critical design constraint and a potential 'show stopper'. Thus, protection from the hazards of severe space radiation is of paramount importance to the agency's vision. It is envisioned to have long duration human presence on the Moon for deep space exploration. The exposures from ionizing radiation - galactic cosmic radiation and solar particle events - and optimized shield design for a swing-by and a long duration Mars mission have been investigated. It is found that the technology of today is inadequate for safe human missions to Mars, and revolutionary technologies need to be developed for long duration and/or deep space missions. The study will provide a guideline for radiation exposure and protection for long duration missions and career astronauts and their safety.

  2. Long-term effect of early-life stress from earthquake exposure on working memory in adulthood.

    Science.gov (United States)

    Li, Na; Wang, Yumei; Zhao, Xiaochuan; Gao, Yuanyuan; Song, Mei; Yu, Lulu; Wang, Lan; Li, Ning; Chen, Qianqian; Li, Yunpeng; Cai, Jiajia; Wang, Xueyi

    2015-01-01

    The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood. A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3-12 months, n=274), prenatal exposure (n=269), and no exposure (born at least 1 year after the earthquake, n=364). The prenatal group was further divided into first, second, and third trimester subgroups based on the timing of exposure during pregnancy. Hopkins Verbal Learning Test-Revised and Brief Visuospatial Memory Test-Revised (BVMT-R) were used to measure the performance of working memory. Unconditional logistic regression analysis was used to analyze the influential factors for impaired working memory. The Hopkins Verbal Learning Test-Revised scores did not show significant difference across the three groups. Compared with no exposure group, the BVMT-R scores were slightly lower in the prenatal exposure group and markedly decreased in the infant exposure group. When the BVMT-R scores were analyzed in three subgroups, the results showed that the subjects whose mothers were exposed to earthquake in the second and third trimesters of pregnancy had significantly lower BVMT-R scores compared with those in the first trimester. Education level and early-life earthquake exposure were identified as independent risk factors for reduced performance of visuospatial memory indicated by lower BVMT-R scores. Infant exposure to earthquake-related stress impairs visuospatial memory in adulthood. Fetuses in the middle and late stages of development are more vulnerable to stress-induced damage that consequently results in impaired visuospatial memory. Education and early-life trauma can also influence the performance of working memory in adulthood.

  3. Long-term exposures to low doses of cobalt nanoparticles induce cell transformation enhanced by oxidative damage.

    Science.gov (United States)

    Annangi, Balasubramanyam; Bach, Jordi; Vales, Gerard; Rubio, Laura; Marcos, Ricard; Hernández, Alba

    2015-03-01

    A weak aspect of the in vitro studies devoted to get information on the toxic, genotoxic and carcinogenic properties of nanomaterials is that they are usually conducted under acute-exposure and high-dose conditions. This makes difficult to extrapolate the results to human beings. To overcome this point, we have evaluated the cell transforming ability of cobalt nanoparticles (CoNPs) after long-term exposures (12 weeks) to sub-toxic doses (0.05 and 0.1 µg/mL). To get further information on whether CoNPs-induced oxidative DNA damage is relevant for CoNPs carcinogenesis, the cell lines selected for the study were the wild-type mouse embryonic fibroblast (MEF Ogg1(+/+)) and its isogenic Ogg1 knockout partner (MEF Ogg1(-)(/)(-)), unable to properly eliminate the 8-OH-dG lesions from DNA. Our initial short-term exposure experiments demonstrate that low doses of CoNPs are able to induce reactive oxygen species (ROS) and that MEF Ogg1(-)(/)(-) cells are more sensitive to CoNPs-induced acute toxicity and oxidative DNA damage. On the other hand, long-term exposures of MEF cells to sub-toxic doses of CoNPs were able to induce cell transformation, as indicated by the observed morphological cell changes, significant increases in the secretion of metalloproteinases (MMPs) and anchorage-independent cell growth ability, all cancer-like phenotypic hallmarks. Interestingly, such changes were significantly dependent on the cell line used, the Ogg1(-)(/)(-) cells being particularly sensitive. Altogether, the data presented here confirms the potential carcinogenic risk of CoNPs and points out the relevance of ROS and Ogg1 genetic background on CoNPs-associated effects.

  4. STROBE-Long-Term Exposure to Ambient Fine Particulate Air Pollution and Hospitalization Due to Peptic Ulcers.

    Science.gov (United States)

    Wong, Chit-Ming; Tsang, Hilda; Lai, Hak-Kan; Thach, Thuan-Quoc; Thomas, G Neil; Chan, King-Pan; Lee, Siu-Yin; Ayres, Jon G; Lam, Tai-Hing; Leung, Wai K

    2016-05-01

    Little is known about the effect of air pollution on the gastrointestinal (GI) system. We investigated the association between long-term exposures to outdoor fine particles (PM2.5) and hospitalization for peptic ulcer diseases (PUDs) in a large cohort of Hong Kong Chinese elderly.A total of 66,820 subjects aged ≥65 years who were enrolled in all 18 Government Elderly Health Service centers of Hong Kong participated in the study voluntarily between 1998 and 2001. They were prospectively followed up for more than 10 years. Annual mean exposures to PM2.5 at residence of individuals were estimated by satellite data through linkage with address details including floor level. All hospital admission records of the subjects up to December 31, 2010 were retrieved from the central database of Hospital Authority. We used Cox regression to estimate the hazard ratio (HR) for PUD hospitalization associated with PM2.5 exposure after adjustment for individual and ecological covariates.A total of 60,273 subjects had completed baseline information including medical, socio-demographic, lifestyle, and anthropometric data at recruitment. During the follow-up period, 1991 (3.3%) subjects had been hospitalized for PUD. The adjusted HR for PUD hospitalization per 10 μg/m of PM2.5 was 1.18 (95% confidence interval: 1.02-1.36, P = 0.02). Further analysis showed that the associations with PM2.5 were significant for gastric ulcers (HR 1.29; 1.09-1.53, P = 0.003) but not for duodenal ulcers (HR 0.98; 0.78 to 1.22, P = 0.81).Long-term exposures to PM2.5 were associated with PUD hospitalization in elder population. The mechanism underlying the PM2.5 in the development of gastric ulcers warrants further research.

  5. Responses of the alga Pseudokirchneriella subcapitata to long-term exposure to metal stress

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Manuela D. [Bioengineering Laboratory, Chemical Engineering Department, ISEP-School of Engineering of Polytechnic Institute of Porto, Porto (Portugal); CEB-Centre of Biological Engineering, University of Minho, Braga (Portugal); Lopes, Ana R. [LEPABE, Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto (Portugal); Soares, Eduardo V., E-mail: evs@isep.ipp.pt [Bioengineering Laboratory, Chemical Engineering Department, ISEP-School of Engineering of Polytechnic Institute of Porto, Porto (Portugal); CEB-Centre of Biological Engineering, University of Minho, Braga (Portugal)

    2015-10-15

    Highlights: • Heavy metals provoke a perturbation of the physiological status of Pseudokirchneriella subcapitata. • Cd(II), Cr(VI) and Cu(II), at high concentrations, cause the loss of membrane integrity. • Cd(II), Cr(VI), Cu(II) and Zn(II) inhibit esterase activity in a dose dependent manner. • Heavy metals affect mitochondrial function and photosynthetic activity. • Fluorescent probes are a useful tool in the identification of toxicity targets of the heavy metals. - Abstract: The green alga Pseudokirchneriella subcapitata has been widely used in ecological risk assessment, usually based on the impact of the toxicants in the alga growth. However, the physiological causes that lead algal growth inhibition are not completely understood. This work aimed to evaluate the biochemical and structural modifications in P. subcapitata after exposure, for 72 h, to three nominal concentrations of Cd(II), Cr(VI), Cu(II) and Zn(II), corresponding approximately to 72 h-EC{sub 10} and 72 h-EC{sub 50} values and a high concentration (above 72 h-EC{sub 90} values). The incubation of algal cells with the highest concentration of Cd(II), Cr(VI) or Cu(II) resulted in a loss of membrane integrity of ~16, 38 and 55%, respectively. For all metals tested, an inhibition of esterase activity, in a dose-dependent manner, was observed. Reduction of chlorophyll a content, decrease of maximum quantum yield of photosystem II and modification of mitochondrial membrane potential was also verified. In conclusion, the exposure of P. subcapitata to metals resulted in a perturbation of the cell physiological status. Principal component analysis revealed that the impairment of esterase activity combined with the reduction of chlorophyll a content were related with the inhibition of growth caused by a prolonged exposure to the heavy metals.

  6. Vibrio anguillarum Is Genetically and Phenotypically Unaffected by Long-Term Continuous Exposure to the Antibacterial Compound Tropodithietic Acid.

    Science.gov (United States)

    Rasmussen, Bastian Barker; Grotkjær, Torben; D'Alvise, Paul W; Yin, Guangliang; Zhang, Faxing; Bunk, Boyke; Spröer, Cathrin; Bentzon-Tilia, Mikkel; Gram, Lone

    2016-08-01

    Minimizing the use of antibiotics in the food production chain is essential for limiting the development and spread of antibiotic-resistant bacteria. One alternative intervention strategy is the use of probiotic bacteria, and bacteria of the marine Roseobacter clade are capable of antagonizing fish-pathogenic vibrios in fish larvae and live feed cultures for fish larvae. The antibacterial compound tropodithietic acid (TDA), an antiporter that disrupts the proton motive force, is key in the antibacterial activity of several roseobacters. Introducing probiotics on a larger scale requires understanding of any potential side effects of long-term exposure of the pathogen to the probionts or any compounds they produce. Here we exposed the fish pathogen Vibrio anguillarum to TDA for several hundred generations in an adaptive evolution experiment. No tolerance or resistance arose during the 90 days of exposure, and whole-genome sequencing of TDA-exposed lineages and clones revealed few mutational changes, compared to lineages grown without TDA. Amino acid-changing mutations were found in two to six different genes per clone; however, no mutations appeared unique to the TDA-exposed lineages or clones. None of the virulence genes of V. anguillarum was affected, and infectivity assays using fish cell lines indicated that the TDA-exposed lineages and clones were less invasive than the wild-type strain. Thus, long-term TDA exposure does not appear to result in TDA resistance and the physiology of V. anguillarum appears unaffected, supporting the application of TDA-producing roseobacters as probiotics in aquaculture. It is important to limit the use of antibiotics in our food production, to reduce the risk of bacteria developing antibiotic resistance. We showed previously that marine bacteria of the Roseobacter clade can prevent or reduce bacterial diseases in fish larvae, acting as probiotics. Roseobacters produce the antimicrobial compound tropodithietic acid (TDA), and we

  7. Evaluating methods for estimating space-time paths of individuals in calculating long-term personal exposure to air pollution

    Science.gov (United States)

    Schmitz, Oliver; Soenario, Ivan; Vaartjes, Ilonca; Strak, Maciek; Hoek, Gerard; Brunekreef, Bert; Dijst, Martin; Karssenberg, Derek

    2016-04-01

    Air pollution is one of the major concerns for human health. Associations between air pollution and health are often calculated using long-term (i.e. years to decades) information on personal exposure for each individual in a cohort. Personal exposure is the air pollution aggregated along the space-time path visited by an individual. As air pollution may vary considerably in space and time, for instance due to motorised traffic, the estimation of the spatio-temporal location of a persons' space-time path is important to identify the personal exposure. However, long term exposure is mostly calculated using the air pollution concentration at the x, y location of someone's home which does not consider that individuals are mobile (commuting, recreation, relocation). This assumption is often made as it is a major challenge to estimate space-time paths for all individuals in large cohorts, mostly because limited information on mobility of individuals is available. We address this issue by evaluating multiple approaches for the calculation of space-time paths, thereby estimating the personal exposure along these space-time paths with hyper resolution air pollution maps at national scale. This allows us to evaluate the effect of the space-time path and resulting personal exposure. Air pollution (e.g. NO2, PM10) was mapped for the entire Netherlands at a resolution of 5×5 m2 using the land use regression models developed in the European Study of Cohorts for Air Pollution Effects (ESCAPE, http://escapeproject.eu/) and the open source software PCRaster (http://www.pcraster.eu). The models use predictor variables like population density, land use, and traffic related data sets, and are able to model spatial variation and within-city variability of annual average concentration values. We approximated space-time paths for all individuals in a cohort using various aggregations, including those representing space-time paths as the outline of a persons' home or associated parcel

  8. Land use regression models as a tool for short, medium and long term exposure to traffic related air pollution.

    Science.gov (United States)

    Dons, Evi; Van Poppel, Martine; Int Panis, Luc; De Prins, Sofie; Berghmans, Patrick; Koppen, Gudrun; Matheeussen, Christine

    2014-04-01

    In the HEAPS (Health Effects of Air Pollution in Antwerp Schools) study the importance of traffic-related air pollution on the school and home location on children's health was assessed. 130 children (aged 6 to 12) from two schools participated in a biomonitoring study measuring oxidative stress, inflammation and cardiovascular markers. Personal exposure of schoolchildren to black carbon (BC) and nitrogen dioxide (NO2) was assessed using both measured and modeled concentrations. Air quality measurements were done in two seasons at approximately 50 locations, including the schools. The land use regression technique was applied to model concentrations at the children's home address and at the schools. In this paper the results of the exposure analysis are given. Concentrations measured at school 2h before the medical examination were used for assessing health effects of short term exposure. Over two seasons, this short term BC exposure ranged from 514 ng/m(3) to 6285 ng/m(3), and for NO2 from 11 μg/m(3) to 36 μg/m(3). An integrated exposure was determined until 10 days before the child's examination, taking into account exposures at home and at school and the time spent in each of these microenvironments. Land use regression estimates were therefore recalculated into daily concentrations by using the temporal trend observed at a fixed monitor of the official air quality network. Concentrations at the children's homes were modeled to estimate long term exposure (from 1457 ng/m(3) to 3874 ng/m(3) for BC; and from 19 μg/m(3) to 51 μg/m(3) for NO2). The land use regression technique proved to be a fast and accurate means for estimating long term and daily BC and NO2 exposure for children living in the Antwerp area. The spatial and temporal resolution was tailored to the needs of the epidemiologists involved in this study. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Long-term consequences of adolescent cannabinoid exposure in adult psychopathology

    Directory of Open Access Journals (Sweden)

    Justine eRenard

    2014-11-01

    Full Text Available Marijuana is the most widely used illicit drug among adolescents and young adults. Unique cognitive, emotional, and social changes occur during this critical period of development from childhood into adulthood. The adolescent brain is in a state of transition and differs from the adult brain with respect to both anatomy (e.g., neuronal connections and morphology and neurochemistry (e.g., dopamine, GABA, and glutamate. These changes are thought to support the emergence of adult cerebral processes and behaviors. The endocannabinoid system plays an important role in development by acting on synaptic plasticity, neuronal cell proliferation, migration, and differentiation. Delta-9-tetrahydrocanabinol (THC, the principal psychoactive component in marijuana, acts as an agonist of the cannabinoid type 1 receptor (CB1R. Thus, over-activation of the endocannabinoid system by chronic exposure to CB1R agonists (e.g. THC, CP-55,940, and WIN55,212-2 during adolescence can dramatically alter brain maturation and cause long-lasting neurobiological changes that ultimately affect the function and behavior of the adult brain. Indeed, emerging evidence from both human and animal studies demonstrates that early-onset marijuana use has long-lasting consequences on cognition; moreover, in humans, this use is associated with a two-fold increase in the risk of developing a psychotic disorder. Here, we review the relationship between cannabinoid exposure during adolescence and the increased risk of neuropsychiatric disorders, focusing on both clinical and animal studies.

  10. Long-term effects of in utero and lactational exposure to butyl paraben in female rats.

    Science.gov (United States)

    Guerra, Marina Trevizan; Sanabria, Marciana; Cagliarani, Stephannie Vieira; Leite, Gabriel Adan Araújo; Borges, Cibele Dos Santos; De Grava Kempinas, Wilma

    2017-03-01

    Parabens are used as preservatives in cosmetic, pharmaceutical, and food industries, and are frequently detected as contaminants in human fluids and tissues. The endocrine disrupting effects of parabens in female rodents include uterotrophic response, steroidogenesis impairment, and ovarian disturbances. The objective of this study was to determine the effects of maternal butyl paraben (BP) exposure on female sexual development. Pregnant Wistar rats were treated subcutaneously with either corn oil or BP at doses of 10, 100, or 200 mg/kg, from gestational day (GD) 12 until GD 20 for female foetal gonad evaluation, and from GD 12 until the end of lactation to evaluate sexual parameters on the female offspring. Immature female rats were also used in the uterotrophic assay to evaluate the possible estrogenic action of parabens. Our results revealed that, in this experimental protocol, BP did not show estrogenic activity at the doses used and did not impair sexual development and fertility capacity in the female rats, but impaired sexual behavior. We conclude that brain sexual development may be more sensitive to BP effects and we speculate that doses higher than 100 mg/kg (the male lowest observed adverse effect level (LOAEL) for rodent reproductive parameters) would be necessary to promote damages in the female reproduction, regarding the same protocol of exposure. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 776-788, 2017.

  11. Long-term effects of early life stress exposure: Role of epigenetic mechanisms.

    Science.gov (United States)

    Silberman, Dafne M; Acosta, Gabriela B; Zorrilla Zubilete, María A

    2016-07-01

    Stress is an adaptive response to demands of the environment and thus essential for survival. Exposure to stress during the first years of life has been shown to have profound effects on the growth and development of an adult individual. There are evidences demonstrating that stressful experiences during gestation or in early life can lead to enhanced susceptibility to mental disorders. Early-life stress triggers hypothalamic-pituitary-adrenocortical (HPA) axis activation and the associated neurochemical reactions following glucocorticoid release are accompanied by a rapid physiological response. An excessive response may affect the developing brain resulting in neurobehavioral and neurochemical changes later in life. This article reviews the data from experimental studies aimed to investigate hormonal, functional, molecular and epigenetic mechanisms involved in the stress response during early-life programming. We think these studies might prove useful for the identification of novel pharmacological targets for more effective treatments of mental disorders.

  12. Early Effects of Long-Term Neurotoxic Lead Exposure in Copper Works Employees

    Directory of Open Access Journals (Sweden)

    Irina Böckelmann

    2011-01-01

    It was found that of the psychometric performance parameters, only the mainly motor performance parameters had a potential for being neurotoxic early indicators. Preferably centrally influenced performance parameters were found to be less suitable early indicators. The lead-exposed subjects exhibited a slowed poststrain resetting behaviour of the vegetative nervous system, which correlated with the individual blood lead level. This was attributed to vagus depression, which had already started in the prevailing situation of exposure and was reflected by diminished cardiac phase duration variability. Our results indicate that it is necessary to more critically choose the lead level standards in the air on the working area. Heart rate variability may be affected even at small lead concentration.

  13. Long term impact of the endocrine disruptor tributyltin on male fertility following a single acute exposure.

    Science.gov (United States)

    Mitra, Sumonto; Srivastava, Ankit; Khandelwal, Shashi

    2017-10-01

    Declining rate of human fertility is a growing concern, where lifestyle and environmental factors play an important role. We recently demonstrated that tributyltin (TBT), an omnipresent endocrine disruptor, affects testicular cells in vitro. In this study, male Wistar rats were gavaged a single dose of 10, 20, and 30 mg/kg TBT-chloride (TBTC) (to mimic accidental exposure in vivo) and sacrificed on day 3 and day 7, respectively. TBT bioavailability was evaluated by estimating total tin content, and essential metal levels were analyzed along with redox molecules (ROS and GSH/GSSG) to understand the effect on physiological conditions. Blood-testicular barrier (BTB) disruption, levels of associated proteins and activity of proteolytic enzymes were evaluated to understand the effect on BTB. Histological analysis of tissue architecture and effect on protein expression of steroidogenic, stress and apoptotic markers were also evaluated. Widespread TBTC pollution can be an eventual threat to male fertility worldwide. © 2017 Wiley Periodicals, Inc.

  14. Circulatory adaptation to long-term high altitude exposure in Aymaras and Caucasians.

    Science.gov (United States)

    Stuber, Thomas; Scherrer, Urs

    2010-01-01

    About 30 million people live above 2500 m in the Andean Mountains of South America. Among them are 5.5 million Aymaras, an ethnic group with its own language, living on the altiplano of Bolivia, Peru, and northern Chile at altitudes of up to 4400 m. In this high altitude region traces of human population go back for more than 2000 years with constant evolutionary pressure on its residents for genetic adaptation to high altitude. Aymaras as the assumed direct descendents of the ancient cultures living in this region were the focus of much research interest during the last decades and several distinctive adaptation patterns to life at high altitude have been described in this ethnic group. The aim of this article was to review the physiology and pathophysiology of circulatory adaptation and maladaptation to longtime altitude exposure in Aymaras and Caucasians.

  15. Modelling long-term trends in lunar exposure to the Earth's plasmasheet

    Directory of Open Access Journals (Sweden)

    M. Hapgood

    2007-10-01

    Full Text Available This paper shows how the exposure of the Moon to the Earth's plasmasheet is subject to decadal variations due to lunar precession. The latter is a key property of the Moon's apparent orbit around the Earth – the nodes of that orbit precess around the ecliptic, completing one revolution every 18.6 years. This precession is responsible for a number of astronomical phenomena, e.g. the year to year drift of solar and lunar eclipse periods. It also controls the ecliptic latitude at which the Moon crosses the magnetotail and thus the number and duration of lunar encounters with the plasmasheet. This paper presents a detailed model of those encounters and applies it to the period 1960 to 2030. This shows that the total lunar exposure to the plasmasheet will vary from 10 h per month at a minimum of the eighteen-year cycle rising to 40 h per month at the maximum. These variations could have a profound impact on the accumulation of charge due plasmasheet electrons impacting the lunar surface. Thus we should expect the level of lunar surface charging to vary over the eighteen-year cycle. The literature contains reports that support this: several observations made during the cycle maximum of 1994–2000 are attributed to bombardment and charging of the lunar surface by plasmasheet electrons. Thus we conclude that lunar surface charging will vary markedly over an eighteen-year cycle driven by lunar precession. It is important to interpret lunar environment measurements in the context of this cycle and to allow for the cycle when designing equipment for deployment on the lunar surface. This is particularly important in respect of developing plans for robotic exploration on the lunar surface during the next cycle maximum of 2012–2019.

  16. Environmental enrichment improves age-related immune system impairment: long-term exposure since adulthood increases life span in mice.

    Science.gov (United States)

    Arranz, Lorena; De Castro, Nuria M; Baeza, Isabel; Maté, Ianire; Viveros, Maria Paz; De la Fuente, Mónica

    2010-08-01

    Age-related changes in immunity have been shown to highly influence morbidity and mortality. The aim of the present work was to study the effects of environmental enrichment (EE) (8-16 weeks) on several functions and oxidative stress parameters of peritoneal leukocytes, previously described as health and longevity markers, in mice at different ages, namely adult (44 +/- 4 weeks), old (69 +/- 4 weeks), and very old (92 +/- 4 weeks). Mortality rates were monitored in control and enriched animals, and effects on survival of long-term exposure to EE until natural death were determined. The results showed that exposure to EE was efficient in improving the function (i.e., macrophage chemotaxis and phagocytosis, lymphocyte chemotaxis and proliferation, natural killer cell activity, interleukin-2 and tumor necrosis factor-alpha levels) and decreasing the oxidative-inflammatory stress (i.e., lowered oxidized glutathione content, xanthine oxidase activity, expression of Toll-like receptors 2 and 4 on CD4 and CD8 cells, and increased reduced glutathione and glutathione peroxidase and catalase activities) of immune cells. These positive effects of EE were especially remarkable in animals at older ages. Importantly, long-term exposure to EE from adult age and until natural death stands out as a useful strategy to extend longevity. Thus, the present work confirms the importance of maintaining active mental and/or physical activity aiming to improve quality of life in terms of immunity, and demonstrates that this active life must be initiated at early stages of the aging process and preserved until death to improve life span.

  17. Long-term health consequences of violence exposure in adolescence: a 26–year prospective study

    Directory of Open Access Journals (Sweden)

    Olofsson Niclas

    2012-06-01

    Full Text Available Abstract Background Violence victimization represents a serious risk factor for health related symptoms, for both men and women. The aim of this study was to evaluate the long-term effects of violence exposure in late adolescence and early adulthood on adult health, physical as well as mental, using a long-term prospective population-based study, with a follow up of 9, 19, and 26 years. Methods The primary data source is a longitudinal panel from one of the longest running social science surveys in the world, the Swedish Level-of-Living surveys (LNU. We analyzed three cohorts, individuals aged 15–19 in 1974 and 1981, and individuals aged 18–19 in 1991 which were followed up 2000. Structured interviews on childhood, family relationships, life-events, living conditions, health history and status, working conditions, behavioral, psychosocial, and demographic variables were repeatedly used in all cohorts. Results Multivariate models of violence exposures in adolescence in the 1974–91 cohorts as predictors of adult health in 2000 are reported for both men and women. Women exposed to violence had raised odds ratios for ill health, measured as heavy illness burden, and poor self rated health, after controlling for possible confounders. No such associations were found for men. Conclusions This study’s findings provide additional empirical support for the importance of policies and practices to identify and prevent violence exposure in adolescence and young adulthood and to supply treatments for adolescence exposed to violence and above all the young women.

  18. Association between Long-Term Exposure to Particulate Matter Air Pollution and Mortality in a South Korean National Cohort: Comparison across Different Exposure Assessment Approaches.

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    Kim, Ok-Jin; Kim, Sun-Young; Kim, Ho

    2017-09-23

    Increasing numbers of cohort studies have reported that long-term exposure to ambient particulate matter is associated with mortality. However, there has been little evidence from Asian countries. We aimed to explore the association between long-term exposure to particulate matter with a diameter ≤10 µm (PM10) and mortality in South Korea, using a nationwide population-based cohort and an improved exposure assessment (EA) incorporating time-varying concentrations and residential addresses (EA1). We also compared the association across different EA approaches. We used information from 275,337 people who underwent health screening from 2002 to 2006 and who had follow-up data for 12 years in the National Health Insurance Service-National Sample Cohort. Individual exposures were computed as 5-year averages using predicted residential district-specific annual-average PM10 concentrations for 2002-2006. We estimated hazard ratios (HRs) of non-accidental and five cause-specific mortalities per 10 µg/m³ increase in PM10 using the Cox proportional hazards model. Then, we compared the association of EA1 with three other approaches based on time-varying concentrations and/or addresses: predictions in each year and addresses at baseline (EA2); predictions at baseline and addresses in each year (EA3); and predictions and addresses at baseline (EA4). We found a marginal association between long-term PM10 and non-accidental mortality. The HRs of five cause-specific mortalities were mostly higher than that of non-accidental mortality, but statistically insignificant. In the comparison between EA approaches, the HRs of EA1 were similar to those of EA2 but higher than EA3 and EA4. Our findings confirmed the association between long-term exposure to PM10 and mortality based on a population-representative cohort in South Korea, and suggested the importance of assessing individual exposure incorporating air pollution changes over time.

  19. Long-term Autophagy and Nrf2 Signaling in the Hippocampi of Developing Mice after Carbon Ion Exposure

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    Ye, Fei; Zhao, Ting; Liu, Xiongxiong; Jin, Xiaodong; Liu, Xinguo; Wang, Tieshan; Li, Qiang

    2015-12-01

    To explore charged particle radiation-induced long-term hippocampus damage, we investigated the expression of autophagy and antioxidant Nrf2 signaling-related proteins in the mouse hippocampus after carbon ion radiation. Heads of immature female Balb/c mice were irradiated with carbon ions of different LETs at various doses. Behavioral tests were performed on the mice after maturation. Acute and chronic expression of LC3-II, p62/SQSTM1, nuclear Nrf2, activated caspase-3 and the Bax/Bcl-2 ratio were measured in the hippocampi. Secondary X-ray insult was adopted to amplify potential damages. Long-term behavioral changes were observed in high-LET carbon ion-irradiated mice. There were no differences in the rates of LC3-II induction and p62/SQSTM1 degradation compared to the control group regardless of whether the mice received the secondary X-ray insult. A high nuclear Nrf2 content and low apoptosis level in hippocampal cells subjected to secondary X-rays were observed for the mice exposed to relatively low-LET carbon ions. Therefore, carbon ion exposure in the immature mouse led to an LET-dependent behavioral change after maturation. Although autophagy was intact, the persistently high nuclear Nrf2 content in the hippocampus might account for the unchanged behavioral pattern in mice exposed to the relatively low-LET carbon ions and the subsequent increased radioresistance of the hippocampus.

  20. Long-term air pollution exposure and living close to busy roads are associated with COPD in women

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    Gehring Ulrike

    2005-12-01

    Full Text Available Abstract Background Lung function and exacerbations of chronic obstructive pulmonary disease (COPD have been associated with short-term exposure to air pollution. However, the effect of long-term exposure to particulate matter from industry and traffic on COPD as defined by lung function has not been evaluated so far. Our study was designed to investigate the influence of long-term exposure to air pollution on respiratory symptoms and pulmonary function in 55-year-old women. We especially focused on COPD as defined by GOLD criteria and additionally compared the effects of air pollution on respiratory symptoms by questionnaire data and by lung function measurements. Methods In consecutive cross sectional studies conducted between 1985–1994, we investigated 4757 women living in the Rhine-Ruhr Basin of Germany. NO2 and PM10 exposure was assessed by measurements done in an 8 km grid, and traffic exposure by distance from the residential address to the nearest major road using Geographic Information System data. Lung function was determined and COPD was defined by using the GOLD criteria. Chronic respiratory symptoms and possible confounders were defined by questionnaire data. Linear and logistic regressions, including random effects were used to account for confounding and clustering on city level. Results The prevalence of COPD (GOLD stages 1–4 was 4.5%. COPD and pulmonary function were strongest affected by PM10 and traffic related exposure. A 7 μg/m3 increase in five year means of PM10 (interquartile range was associated with a 5.1% (95% CI 2.5%–7.7% decrease in FEV1, a 3.7% (95% CI 1.8%–5.5% decrease in FVC and an odds ratio (OR of 1.33 (95% CI 1.03–1.72 for COPD. Women living less than 100 m from a busy road also had a significantly decreased lung function and COPD was 1.79 times more likely (95% CI 1.06–3.02 than for those living farther away. Chronic symptoms as based on questionnaire information showed effects in the same

  1. Long-term exposure to traffic-related air pollution and the risk of coronary heart disease hospitalization and mortality.

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    Gan, Wen Qi; Koehoorn, Mieke; Davies, Hugh W; Demers, Paul A; Tamburic, Lillian; Brauer, Michael

    2011-04-01

    Epidemiologic studies have demonstrated that exposure to road traffic is associated with adverse cardiovascular outcomes. We aimed to identify specific traffic-related air pollutants that are associated with the risk of coronary heart disease (CHD) morbidity and mortality to support evidence-based environmental policy making. This population-based cohort study included a 5-year exposure period and a 4-year follow-up period. All residents 45-85 years of age who resided in Metropolitan Vancouver during the exposure period and without known CHD at baseline were included in this study (n=452,735). Individual exposures to traffic-related air pollutants including black carbon, fine particles [aerodynamic diameter ≤ 2.5 µm (PM(2.5))], nitrogen dioxide (NO(2)), and nitric oxide were estimated at residences of the subjects using land-use regression models and integrating changes in residences during the exposure period. CHD hospitalizations and deaths during the follow-up period were identified from provincial hospitalization and death registration records. An interquartile range elevation in the average concentration of black carbon (0.94 × 10(-5)/m filter absorbance, equivalent to approximately 0.8 µg/m(3) elemental carbon) was associated with a 3% increase in CHD hospitalization (95% confidence interval, 1-5%) and a 6% increase in CHD mortality (3-9%) after adjusting for age, sex, preexisting comorbidity, neighborhood socioeconomic status, and copollutants (PM(2.5) and NO(2)). There were clear linear exposure-response relationships between black carbon and coronary events. Long-term exposure to traffic-related fine particulate air pollution, indicated by black carbon, may partly explain the observed associations between exposure to road traffic and adverse cardiovascular outcomes.

  2. Systemic and local effects of long-term exposure to alkaline drinking water in rats.

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    Merne, M E; Syrjänen, K J; Syrjänen, S M

    2001-08-01

    Alkaline conditions in the oral cavity may be caused by a variety of stimuli, including tobacco products, antacids, alkaline drinking water or bicarbonate toothpaste. The effects of alkaline pH on oral mucosa have not been systematically studied. To assess the systemic (organ) and local (oral mucosal) effects of alkalinity, drinking water supplemented with Ca(OH)2 or NaOH, with pH 11.2 or 12 was administered to rats (n = 36) for 52 weeks. Tissues were subjected to histopathological examination; oral mucosal biopsy samples were also subjected to immunohistochemical (IHC) analyses for pankeratin, CK19, CK5, CK4, PCNA, ICAM-1, CD44, CD68, S-100, HSP 60, HSP70, and HSP90. At completion of the study, animals in the study groups had lower body weights (up to 29% less) than controls despite equal food and water intake, suggesting a systemic response to the alkaline treatment. The lowest body weight was found in rats exposed to water with the highest pH value and starting the experiment when young (6 weeks). No histological changes attributable to alkaline exposure occurred in the oral mucosa or other tissues studied. Alkaline exposure did not affect cell proliferation in the oral epithelium, as shown by the equal expression of PCNA in groups. The up-regulation of HSP70 protein expression in the oral mucosa of rats exposed to alkaline water, especially Ca(OH)2 treated rats, may indicate a protective response. Intercellular adhesion molecule-1 (ICAM-1) positivity was lost in 6/12 rats treated with Ca(OH)2 with pH 11.2, and loss of CD44 expression was seen in 3/6 rats in both study groups exposed to alkaline water with pH 12. The results suggest that the oral mucosa in rats is resistant to the effects of highly alkaline drinking water. However, high alkalinity may have some unknown systemic effects leading to growth retardation, the cause of which remains to be determined.

  3. Long-Term Exposure to Ambient Air Pollution and Metabolic Syndrome in Adults.

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    Ikenna C Eze

    Full Text Available Air pollutants (AP play a role in subclinical inflammation, and are associated with cardiovascular morbidity and mortality. Metabolic syndrome (MetS is inflammatory and precedes cardiovascular morbidity and type 2 diabetes. Thus, a positive association between AP and MetS may be hypothesized. We explored this association, (taking into account, pathway-specific MetS definitions, and its potential modifiers in Swiss adults. We studied 3769 participants of the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults, reporting at least four-hour fasting time before venepuncture. AP exposures were 10-year mean residential PM10 (particulate matter <10μm in diameter and NO2 (nitrogen dioxide. Outcomes included MetS defined by World Health Organization (MetS-W, International Diabetes Federation (MetS-I and Adult Treatment Panel-III (MetS-A using four- and eight-hour fasting time limits. We also explored associations with individual components of MetS. We applied mixed logistic regression models to explore these associations. The prevalence of MetS-W, MetS-I and MetS-A were 10%, 22% and 18% respectively. Odds of MetS-W, MetS-I and MetS-A increased by 72% (51-102%, 31% (11-54% and 18% (4-34% per 10μg/m3 increase in 10-year mean PM10. We observed weaker associations with NO2. Associations were stronger among physically-active, ever-smokers and non-diabetic participants especially with PM10 (p<0.05. Associations remained robust across various sensitivity analyses including ten imputations of missing observations and exclusion of diabetes cases. The observed associations between AP exposure and MetS were sensitive to MetS definitions. Regarding the MetS components, we observed strongest associations with impaired fasting glycemia, and positive but weaker associations with hypertension and waist-circumference-based obesity. Cardio-metabolic effects of AP may be majorly driven by impairment of glucose homeostasis, and to a less

  4. Long-term occupational exposure to organic solvents affects color vision, contrast sensitivity and visual fields.

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    Thiago Leiros Costa

    Full Text Available The purpose of this study was to evaluate the visual outcome of chronic occupational exposure to a mixture of organic solvents by measuring color discrimination, achromatic contrast sensitivity and visual fields in a group of gas station workers. We tested 25 workers (20 males and 25 controls with no history of chronic exposure to solvents (10 males. All participants had normal ophthalmologic exams. Subjects had worked in gas stations on an average of 9.6 ± 6.2 years. Color vision was evaluated with the Lanthony D15d and Cambridge Colour Test (CCT. Visual field assessment consisted of white-on-white 24-2 automatic perimetry (Humphrey II-750i. Contrast sensitivity was measured for sinusoidal gratings of 0.2, 0.5, 1.0, 2.0, 5.0, 10.0 and 20.0 cycles per degree (cpd. Results from both groups were compared using the Mann-Whitney U test. The number of errors in the D15d was higher for workers relative to controls (p<0.01. Their CCT color discrimination thresholds were elevated compared to the control group along the protan, deutan and tritan confusion axes (p<0.01, and their ellipse area and ellipticity were higher (p<0.01. Genetic analysis of subjects with very elevated color discrimination thresholds excluded congenital causes for the visual losses. Automated perimetry thresholds showed elevation in the 9°, 15° and 21° of eccentricity (p<0.01 and in MD and PSD indexes (p<0.01. Contrast sensitivity losses were found for all spatial frequencies measured (p<0.01 except for 0.5 cpd. Significant correlation was found between previous working years and deutan axis thresholds (rho = 0.59; p<0.05, indexes of the Lanthony D15d (rho=0.52; p<0.05, perimetry results in the fovea (rho= -0.51; p<0.05 and at 3, 9 and 15 degrees of eccentricity (rho= -0.46; p<0.05. Extensive and diffuse visual changes were found, suggesting that specific occupational limits should be created.

  5. Long-term neurobehavioral health effects of methyl parathion exposure in children in Mississippi and Ohio.

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    Ruckart, Perri Zeitz; Kakolewski, Kirsten; Bove, Frank J; Kaye, Wendy E

    2004-01-01

    Methyl parathion (MP), an organophosphate pesticide licensed only for agricultural uses, was sprayed illegally for pest control in Mississippi and Ohio residences. To evaluate the association between MP exposure and neurobehavioral development, we assessed children 6 years or younger at the time of the spraying and local comparison groups of unexposed children using the Pediatric Environmental Neurobehavioral Test Battery (PENTB). The PENTB is composed of informant-based procedures (parent interview and questionnaires) and performance-based procedures (neurobehavioral tests for children 4 years or older) that evaluate cognitive, motor, sensory, and affect domains essential to neurobehavioral assessment. Children were classified as exposed or unexposed on the basis of urinary para-nitrophenol levels and environmental wipe samples for MP. Exposed children had more difficulties with tasks involving short-term memory and attention. Additionally, parents of exposed children reported that their children had more behavioral and motor skill problems than did parents of unexposed children. However, these effects were not consistently seen at both sites. There were no differences between exposed and unexposed children in tests for general intelligence, the integration of visual and motor skills, and multistep processing. Our findings suggest that MP might be associated with subtle changes to short-term memory and attention and contribute to problems with motor skills and some behaviors, but the results of the study are not conclusive.

  6. Depression, pain, exposure to stressful life events, and long-term outcomes in temporomandibular disorder patients.

    Science.gov (United States)

    Auerbach, S M; Laskin, D M; Frantsve, L M; Orr, T

    2001-06-01

    This study investigated the role of psychological factors in temporomandibular disorders (TMD). Orofacial pain patients' pretreatment levels of depression, disability caused by pain, and exposure to stressful life events were measured, and differences on these variables between temporomandibular joint (TMJ) disease patients and patients whose pain was of muscular origin (MPD) were evaluated. The use of these variables and patient diagnostic status in predicting response to treatment in a subsample of these patients was also evaluated. Before undergoing treatment, 258 patients were administered the Beck Depression Inventory (BDI), the Pain Disability Index (PDI), and the Social Readjustment Rating Scale (SRRS). Follow-up data on pain disability, current level of pain, depression, and satisfaction with treatment were obtained on 48 of these patients who were contacted at varying intervals after completing treatment. BDI scores obtained at the outset of treatment were significantly elevated and were positively correlated with SRRS and PDI scores. MPD patients had higher SRRS, BDI depression, and PDI pain disability scores than TMJ patients, and differences between the 2 groups in pain disability were greatest in areas that are often sources of interpersonal stress. Among follow-up patients, PDI scores declined after treatment, with MPD patients showing greater decreases than TMJ patients. Independent of patients' diagnostic status, their pretreatment PDI scores were predictive of their pain level at follow-up and were inversely related to their degree of satisfaction with treatment at follow-up; their pretreatment BDI scores were predictive of their depression level at follow-up. The findings are consistent with previous research indicating a link between emotional dysfunction and TMD and are largely supportive of the conclusion that psychological factors play a more pronounced role when pain is of muscular origin. Promising behavioral interventions are available for

  7. Long-term health effects of early life exposure to tetrachloroethylene (PCE)-contaminated drinking water: a retrospective cohort study.

    Science.gov (United States)

    Aschengrau, Ann; Winter, Michael R; Vieira, Veronica M; Webster, Thomas F; Janulewicz, Patricia A; Gallagher, Lisa G; Weinberg, Janice; Ozonoff, David M

    2015-04-12

    While adult exposure to PCE is known to have toxic effects, there is little information on the long-term impact of prenatal and early childhood exposure. We undertook a retrospective cohort study to examine the effects of their early life exposure to PCE-contaminated drinking water. This retrospective cohort study examined whether prenatal and early childhood exposure to PCE-contaminated drinking water influenced the risk of a variety of chronic conditions among adults who were born between 1969 and 1983 in the Cape Cod area of Massachusetts. Eight hundred and thirty-one participants with prenatal and early childhood PCE exposure and 547 unexposed participants were studied. Individuals completed questionnaires to gather information on demographic characteristics, chronic conditions, and other sources of solvent exposure. The location of residences from birth through 1990 were used to estimate PCE exposure with U.S. EPA's water distribution system modeling software (EPANET) modified to incorporate a leaching and transport model. No associations were observed between early life PCE exposure and current occurrence of obesity, diabetes, cardiovascular disease, hypertension, color blindness, near- and far sightedness and dry eyes. In contrast, a 1.8-fold increased risk of cancer (95% CI: 0.8, 4.0) was seen among individuals with any early life exposure. These results were based on 31 participants (23 exposed and 8 unexposed) who reported cancers at a variety of anatomical sites, particularly the cervix. A 1.5-fold increase in the risk of epilepsy (95% CI: 0.6, 3.6, based on 16 exposed and 7 unexposed participants) was also observed among individuals with any early life exposure that was further increased to 1.8 (95% CI: 0.7, 4.6) among those with exposure at or above the sample median. These results suggest that the risk of epilepsy and certain types of cancer such as cervical cancer may be increased among adults who were exposed to PCE-contaminated drinking water

  8. Recent and Long-Term Soccer Heading Exposure Is Differentially Associated With Neuropsychological Function in Amateur Players.

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    Levitch, Cara F; Zimmerman, Molly E; Lubin, Naomi; Kim, Namhee; Lipton, Richard B; Stewart, Walter F; Kim, Mimi; Lipton, Michael L

    2017-08-22

    The present study examined the relative contribution of recent or long-term heading to neuropsychological function in amateur adult soccer players. Soccer players completed a baseline questionnaire (HeadCount-12m) to ascertain heading during the prior 12 months (long-term heading, LTH) and an online questionnaire (HeadCount-2w) every 3 months to ascertain heading during the prior 2 weeks (recent heading, RH). Cogstate, a battery of six neuropsychological tests, was administered to assess neuropsychological function. Generalized estimating equations were used to test if LTH or RH was associated with neuropsychological function while accounting for the role of recognized concussion. A total of 311 soccer players completed 630 HeadCount-2w. Participants had an average age of 26 years. Participants headed the ball a median of 611 times/year (mean=1,384.03) and 9.50 times/2 weeks (mean=34.17). High levels of RH were significantly associated with reduced performance on a task of psychomotor speed (p=.02), while high levels of LTH were significantly associated with poorer performance on tasks of verbal learning (p=.03) and verbal memory (p=.04). Significantly better attention (p=.02) was detectable at moderately high levels of RH, but not at the highest level of RH. One hundred and seven (34.4%) participants reported a lifetime history of concussion, but this was not related to neuropsychological function and did not modify the association of RH or LTH with neuropsychological function. High levels of both RH and LTH were associated with poorer neuropsychological function, but on different domains. The clinical manifestations following repetitive exposure to heading could change with chronicity of exposure. (JINS, 2017, 23, 1-9).

  9. Triglyceride accumulation in long-term cultures of adult rat hepatocytes by chronic exposure to Aroclor 1254.

    Science.gov (United States)

    Mendoza-Figueroa, T; Hernández, A; López, M L

    1989-01-01

    The effect of chronic exposure to micromolar concentrations of Aroclor 1254 (Aro) on the hepatic lipid metabolism was studied in long-term cultures of adult rat hepatocytes. Hepatocytes were cocultivated with mitomycin C-treated 3T3 cells and exposed for 2 wk to Aroclor 1254 concentrations ranging from 0.01 to 20 micrograms/ml. The Aro-exposed cultures showed intracytoplasmic lipid droplets and a maximum increase of 55% in the triglyceride (TG) content and of 4.4-fold in the cytochrome P-450 content. Labeling studies with [14C]acetic and [14C]oleic acid showed no changes in the uptake of fatty acid and TG precursors by the Aro-treated cultures; the synthesis of cellular lipids from [14C]acetic acid was slightly inhibited by Aroclor 1254, but that from [14C]oleic acid was increased, specially for TG (37%). The secretion of total lipids and TG was 2.1- and 2.7-fold lower, respectively, in the cultures treated with 20 micrograms/ml of Aroclor 1254, resulting in an increase of 1.9-fold in the intracellular content of TG. The synthesis of cellular proteins labeled with [3H]leucine was unchanged in the Aro-treated cultures, but the secretion of exportable proteins was 1.7-fold lower in the cultures treated with 20 micrograms/ml of Aroclor 1254. Our results showed that long-term exposure to in vivo relevant concentrations of Aroclor 1254 produced morphological and biochemical changes in cultured hepatocytes, like those described in vivo, and intracellular TG accumulation due mostly to impaired secretion of TG by the hepatocytes. Our results also suggest that this culture system could be useful for the screening of toxic agents producing fatty liver and the study of the involved mechanism(s).

  10. Triglyceride accumulation in long-term cultures of adult rat hepatocytes by chronic exposure to Aroclor 1254

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    Mendoza-Figueroa, T.; Hernandez, A.; de Lourdes Lopez, M. (Instituto Politecnico Nacional, Mexico City (Mexico))

    1989-01-01

    The effect of chronic exposure to micromolar concentrations of Aroclor 1254 (Aro) on the hepatic lipid metabolism was studied in long-term cultures of adult rat hepatocytes. Hepatocytes were cocultivated with mytomicin C-treated 3T3 cells and exposed for 2 wk to Aroclor 1254 concentrations ranging from 0.01 to 20 {mu}g/ml. The Aro-exposed cultures showed intracytoplasmic lipid droplets and a maximum increase of 55% in the triglyceride (TG) content and of 4.4-fold in the cytochrome P-450 content. Labeling studies with ({sup 14}C)acetic and ({sup 14}C)oleic acid showed no changes in the uptake of fatty acid and TG precursors by the Aro-treated cultures; the synthesis of cellular lipids from ({sup 14}C)acetic acid was slightly inhibited by Aroclor 1254, but that from ({sup 14}C)oleic acid was increased, specially for TF (37%). The secretion of total lipids and TG was 2.1- and 2.7-fold lower, respectively, in the cultures treated with 20 {mu}g/ml of Aroclor 1254, resulting in an increase of 1.9-fold in the intracellular content of TG. The synthesis of cellular proteins labeled with ({sup 3}H)leucine was unchanged in the Aro-treated cultures, but the secretion of exportable proteins was 1.7-fold lower in the cultures treated with 20 {mu}g/ml of Aroclor 1254. Our results showed that long-term exposure to in vivo relevant concentrations of Aroclor 1254 produced morphological and biochemical changes in cultured hepatocytes, like those described in vivo, and intracellular TG accumulation due mostly to impaired secretion of TG by the hepatocytes. Our results also suggest that this culture system could be useful for the screening of toxic agents producing fatty liver and the study of the involved mechanism(s).

  11. Long-Term Effects of Exposure to Ionizing Irradiation on Periodontal Health Status – The Tinea capitis Cohort Study

    Science.gov (United States)

    Sadetzki, Siegal; Chetrit, Angela; Sgan-Cohen, Harold D.; Mann, Jonathan; Amitai, Tova; Even-Nir, Hadas; Vered, Yuval

    2015-01-01

    Studies among long-term survivors of childhood cancer who had received high-dose irradiation therapy of 4–60 Gy, demonstrated acute and chronic dental effects, including periodontal diseases. However, the possible effects of low to moderate doses of radiation on dental health are sparse. The aim of this study is to investigate the association between childhood exposure to low–moderate doses of ionizing radiation and periodontal health following 50 years since exposure. The study population included 253 irradiated subjects (treated for Tinea capitis in the 1950s) and, 162 non-irradiated subjects. The estimated dose to the teeth was 0.2–0.4 Gy. Dental examination was performed according to the community periodontal index (CPI). Socioeconomic and health behavior variables were obtained through a personal questionnaire. Periodontal disease was operationally defined as “deep periodontal pockets.” A multivariate logistic regression model was used for the association of irradiation status and other independent variables with periodontal status. The results showed that among the irradiated subjects, 23%, (95% CI 18–28%) demonstrated complete edentulousness or insufficient teeth for CPI scoring as compared to 13% (95% CI 8–19%) among the non-irradiated subjects (p = 0.01). Periodontal disease was detected among 54% of the irradiated subjects as compared to 40% of the non-irradiated (p = 0.008). Controlling for education and smoking, the ORs for the association between radiation and periodontal disease were 1.61 (95% CI 1.01–2.57) and 1.95 (95% CI 1.1–3.5) for ever never and per 1 Gy absorbed in the salivary gland, respectively. In line with other studies, a protective effect for periodontal diseases among those with high education and an increased risk for ever smokers were observed. In conclusion, childhood exposure to low-moderate doses of ionizing radiation might be associated with later outcomes of dental health. The results add

  12. Long term effects of exposure to ionizing irradiation on periodontal health status – the Tinea Capitis cohort study

    Directory of Open Access Journals (Sweden)

    Siegal eSadetzki

    2015-10-01

    Full Text Available Studies among long term survivors of childhood cancer who had received high dose irradiation therapy of 4-60 Gy, demonstrated acute and chronic dental effects including periodontal diseases. However, the possible effects of low to moderate doses of radiation on dental health are sparse. The aim of this study is to investigate the association between childhood exposure to low-moderate doses of ionizing radiation and periodontal health following 50 years from the exposure. The study population included 253 irradiated subjects (treated for Tinea Capitis in the 1950s and, 162 non-irradiated subjects, treated for Tinea Capitis in the 1950s. The estimated dose to the teeth was 0.2-0.4Gy. Dental examination was performed according to the Community Periodontal Index (CPI. Socio-economic and health behavior variables were obtained through a personal questionnaire. Periodontal disease was operationally defined as deep periodontal pockets. A multivariate logistic regression model was used for the association of irradiation status and other independent variables with periodontal status.The results showed that among the irradiated subjects, 23% (95% CI 18%-28% demonstrated complete edentulousness or insufficient teeth for CPI scoring as compared to 13% (95% CI 8%-19% among the non-irradiated subjects (p=0.01. Periodontal disease was detected among 54% of the irradiated subjects as compared to 40% of the non-irradiated (p=0.008. Controlling for education and smoking, the ORs for the association between radiation and periodontal disease were 1.61 (95% CI 1.01-2.57 and 1.95 (95% CI 1.1-3.5 for ever never and per 1 Gy absorbed in the salivary gland, respectively. In line with other studies, a protective effect for periodontal diseases among those with high education and an increased risk for ever smokers were observed. In conclusion, childhood exposure to low-moderate doses of ionizing radiation might be associated with later outcomes of dental health. The

  13. Comparison of the long-term behavioral effects of neonatal exposure to retigabine or phenobarbital in rats.

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    Frankel, Sari; Medvedeva, Natalia; Gutherz, Samuel; Kulick, Catherine; Kondratyev, Alexei; Forcelli, Patrick A

    2016-04-01

    Anticonvulsant drugs, when given during vulnerable periods of brain development, can have long-lasting consequences on nervous system function. In rats, the second postnatal week approximately corresponds to the late third trimester of gestation/early infancy in humans. Exposure to phenobarbital during this period has been associated with deficits in learning and memory, anxiety-like behavior, and social behavior, among other domains. Phenobarbital is the most common anticonvulsant drug used in neonatology. Several other drugs, such as lamotrigine, phenytoin, and clonazepam, have also been reported to trigger behavioral changes. A new generation anticonvulsant drug, retigabine, has not previously been evaluated for long-term effects on behavior. Retigabine acts as an activator of KCNQ channels, a mechanism that is unique among anticonvulsants. Here, we examined the effects retigabine exposure from postnatal day (P)7 to P14 on behavior in adult rats. We compared these effects with those produced by phenobarbital (as a positive control) and saline (as a negative control). Motor behavior was assessed by using the open field and rotarod, anxiety-like behavior by the open field, elevated plus maze, and light-dark transition task, and learning/memory by the passive avoidance task; social interactions were assessed in same-treatment pairs, and nociceptive sensitivity was assessed via the tail-flick assay. Motor behavior was unaltered by exposure to either drug. We found that retigabine exposure and phenobarbital exposure both induced increased anxiety-like behavior in adult animals. Phenobarbital, but not retigabine, exposure impaired learning and memory. These drugs also differed in their effects on social behavior, with retigabine-exposed animals displaying greater social interaction than phenobarbital-exposed animals. These results indicate that neonatal retigabine induces a subset of behavioral alterations previously described for other anticonvulsant drugs and extend

  14. Porphyrin production and excretion by long-term cultures of adult rat hepatocytes and effect of lead exposure.

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    Quintanilla-Vega, B; Hernández, A; López, M L; García-Vargas, G; Cebrián, M E; Mendoza-Figueroa, T

    1995-09-18

    Porphyrin production and excretion and the effects of lead exposure were studied in long-term cultures of adult rat hepatocytes cultured on a feeder layer of 3T3 cells after addition of 5-aminolevulinic acid. Porphyrin excretion into the culture medium showed an irregular profile during the first 10 days, with a maximum increase of 50% at day 4 and at day 10 a value similar to that of day 1. Thereafter, porphyrin excretion decreased progressively to 18% of the initial value after 4 weeks. The cellular porphyrin content, after 7 and 28 days in culture, reached values 3.8 and 2.4-fold higher than the corresponding day 1 value. The exposure to 0.5 and 2.4 microM Pb2+ for up to 28 days produced a biphasic effect on porphyrin excretion. Firstly, there was a progressive decrease up to 81% during the first 6 days of lead exposure and, secondly, this effect was followed by an increase reaching control values at day 15 and of up to 6.7-fold after 22 days of exposure to 2.4 microM Pb2+. Similar changes were observed in cellular porphyrin content. The exposure to 0.5 and 2.4 microM Pb2+ for 2 and 4 weeks also produced morphological alterations and release of cytoplasmic enzymes. Our results show that hepatocytes cultured on 3T3 cells produce and excrete porphyrins for 28 days and that exposure for 4 weeks to micromolar lead concentrations alters these functions and cell morphology and produces cytotoxic effects which are better evaluated by monitoring alterations in porphyrin excretion than by enzyme leakage. They also suggest that this culture system is a useful model for assessing the toxic effects of xenobiotics on the biosynthesis of heme by liver cells.

  15. Fasciola gigantica: cercarial shedding pattern from Lymnaea natalensis after long-term exposure to cadmium at different temperatures.

    Science.gov (United States)

    Soliman, Maha F M

    2009-04-01

    Little is known about the response of Fasciola spp., inside its snail host to pollutant toxicity. The effect of long-term exposure of Lymnaea natalensis to 0.1 microg/l, 10 microg/l, or 100 microg/l cadmium (Cd) on the infection rates with F. gigantica, percentage of cercariae-shedding snails and cercariae shedding pattern was investigated. The snails were exposed to Cd for 7 days either pre-infection with single Fasciola miracidium or during the late pre-patent period of the infection. The possible interaction between metal exposure and acclimatization temperature was also studied in three ranges; 16-18 degrees C, 23-25 degrees C and 30-32 degrees C. Results clearly showed that host exposure to 100 microg/l Cd significantly affected the pattern of Fasciola development inside its snail host, and that the acclimatization temperature was a key factor affecting the role played by Cd. Pre-infection exposure to Cd caused a significant reduction in the infection rates where the effect was temperature-dependent. Post-infection exposure to Cd significantly increased the percentage of cercariae-shedding snails; the effect was temperature-independent. Interestingly, post-infection exposure significantly altered the differential cercarial output pattern, while no clear impact on the total was found. The alteration in the differential cercarial output was represented as a significantly higher proportion of floating metacercaria as compared to fixed ones and also higher proportion of dead cercariae which may directly reduce the transmission of Fasciola to the final host. The mechanisms of cadmium impact are briefly discussed.

  16. Long-term exposure to benzalkonium chloride disinfectants results in change of microbial community structure and increased antimicrobial resistance.

    Science.gov (United States)

    Tandukar, Madan; Oh, Seungdae; Tezel, Ulas; Konstantinidis, Konstantinos T; Pavlostathis, Spyros G

    2013-09-03

    The effect of benzalkonium chlorides (BACs), a widely used class of quaternary ammonium disinfectants, on microbial community structure and antimicrobial resistance was investigated using three aerobic microbial communities: BACs-unexposed (DP, fed a mixture of dextrin/peptone), BACs-exposed (DPB, fed a mixture of dextrin/peptone and BACs), and BACs-enriched (B, fed only BACs). Long-term exposure to BACs reduced community diversity and resulted in the enrichment of BAC-resistant species, predominantly Pseudomonas species. Exposure of the two microbial communities to BACs significantly decreased their susceptibility to BACs as well as three clinically relevant antibiotics (penicillin G, tetracycline, ciprofloxacin). Increased resistance to BACs and penicillin G of the two BACs-exposed communities is predominantly attributed to degradation or transformation of these compounds, whereas resistance to tetracycline and ciprofloxacin is largely due to the activity of efflux pumps. Quantification of several key multidrug resistance genes showed a much higher number of copies of these genes in the DPB and B microbial communities compared to the DP community. Collectively, our findings indicate that exposure of a microbial community to BACs results in increased antibiotic resistance, which has important implications for both human and environmental health.

  17. Using smartphones to collect time-activity data for long-term personal-level air pollution exposure assessment.

    Science.gov (United States)

    Glasgow, Mark L; Rudra, Carole B; Yoo, Eun-Hye; Demirbas, Murat; Merriman, Joel; Nayak, Pramod; Crabtree-Ide, Christina; Szpiro, Adam A; Rudra, Atri; Wactawski-Wende, Jean; Mu, Lina

    2016-06-01

    Because of the spatiotemporal variability of people and air pollutants within cities, it is important to account for a person's movements over time when estimating personal air pollution exposure. This study aimed to examine the feasibility of using smartphones to collect personal-level time-activity data. Using Skyhook Wireless's hybrid geolocation module, we developed "Apolux" (Air, Pollution, Exposure), an Android(TM) smartphone application designed to track participants' location in 5-min intervals for 3 months. From 42 participants, we compared Apolux data with contemporaneous data from two self-reported, 24-h time-activity diaries. About three-fourths of measurements were collected within 5 min of each other (mean=74.14%), and 79% of participants reporting constantly powered-on smartphones (n=38) had a daily average data collection frequency of data collection occurred. The discrepancy between diary points and corresponding Apolux data was 342.3 m (Euclidian distance) and varied across mobile networks. This study's high compliance and feasibility for data collection demonstrates the potential for integrating smartphone-based time-activity data into long-term and large-scale air pollution exposure studies.

  18. Mental health benefits of long-term exposure to residential green and blue spaces: a systematic review.

    Science.gov (United States)

    Gascon, Mireia; Triguero-Mas, Margarita; Martínez, David; Dadvand, Payam; Forns, Joan; Plasència, Antoni; Nieuwenhuijsen, Mark J

    2015-04-22

    Many studies conducted during the last decade suggest the mental health benefits of green and blue spaces. We aimed to systematically review the available literature on the long-term mental health benefits of residential green and blue spaces by including studies that used standardized tools or objective measures of both the exposures and the outcomes of interest. We followed the PRISMA statement guidelines for reporting systematic reviews and meta-analysis. In total 28 studies were included in the systematic review. We found limited evidence for a causal relationship between surrounding greenness and mental health in adults, whereas the evidence was inadequate in children. The evidence was also inadequate for the other exposures evaluated (access to green spaces, quality of green spaces, and blue spaces) in both adults and children. The main limitation was the limited number of studies, together with the heterogeneity regarding exposure assessment. Given the increase in mental health problems and the current rapid urbanization worldwide, results of the present systematic review should be taken into account in future urban planning. However, further research is needed to provide more consistent evidence and more detailed information on the mechanisms and the characteristics of the green and blue spaces that promote better mental health. We provide recommendations for future studies in order to provide consistent and evidence-based recommendations for policy makers.

  19. Mental Health Benefits of Long-Term Exposure to Residential Green and Blue Spaces: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Mireia Gascon

    2015-04-01

    Full Text Available Many studies conducted during the last decade suggest the mental health benefits of green and blue spaces. We aimed to systematically review the available literature on the long-term mental health benefits of residential green and blue spaces by including studies that used standardized tools or objective measures of both the exposures and the outcomes of interest. We followed the PRISMA statement guidelines for reporting systematic reviews and meta-analysis. In total 28 studies were included in the systematic review. We found limited evidence for a causal relationship between surrounding greenness and mental health in adults, whereas the evidence was inadequate in children. The evidence was also inadequate for the other exposures evaluated (access to green spaces, quality of green spaces, and blue spaces in both adults and children. The main limitation was the limited number of studies, together with the heterogeneity regarding exposure assessment. Given the increase in mental health problems and the current rapid urbanization worldwide, results of the present systematic review should be taken into account in future urban planning. However, further research is needed to provide more consistent evidence and more detailed information on the mechanisms and the characteristics of the green and blue spaces that promote better mental health. We provide recommendations for future studies in order to provide consistent and evidence-based recommendations for policy makers.

  20. Long-term exposure to mobile communication radiation: an analysis of time-variability of electric field level in GSM900 downlink channels.

    Science.gov (United States)

    Miclaus, Simona; Bechet, Paul; Gheorghevici, Marius

    2013-04-01

    Interest for knowing long-term human exposure levels due to mobile communications has increased in the last years. It has been shown that short-term exposure assessment made under standard procedural restrictions is not reliable when it comes to conclusions on long-term exposure levels. The present work is the result of a several week analysis of time variability of electric field level inside traffic and control channels of the GSM900 mobile communication downlink band and it indicates that a temporal model to allow future predictions of exposure on the long run is obtainable. Collecting, processing and statistically analysing the data provide expression of the maximum and weighted field strengths and their evolution in time. Specific electromagnetic footprints of the channels have been extracted, differentiations between their characteristics have been emphasised and practical advice is provided, with the scope of contributing to the development of reliable procedures for long-term exposure assessment.

  1. Long-term effect of early-life stress from earthquake exposure on working memory in adulthood

    Directory of Open Access Journals (Sweden)

    Li N

    2015-11-01

    Full Text Available Na Li,1-3* Yumei Wang,1-3* Xiaochuan Zhao,1-3 Yuanyuan Gao,1-3 Mei Song,1-3 Lulu Yu,1-3 Lan Wang,1-3 Ning Li,1-3 Qianqian Chen,1-3 Yunpeng Li,1-3 Jiajia Cai,1-3 Xueyi Wang1-31Department of Psychiatry, The First Hospital of Hebei Medical University, 2Mental Health Institute of Hebei Medical University, 3Brain Ageing and Cognitive Neuroscience Laboratory, Hebei, People’s Republic of China *These authors contributed equally to this work Objective: The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood.Methods: A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3–12 months, n=274, prenatal exposure (n=269, and no exposure (born at least 1 year after the earthquake, n=364. The prenatal group was further divided into first, second, and third trimester subgroups based on the timing of exposure during pregnancy. Hopkins Verbal Learning Test-Revised and Brief Visuospatial Memory Test-Revised (BVMT-R were used to measure the performance of working memory. Unconditional logistic regression analysis was used to analyze the influential factors for impaired working memory.Results: The Hopkins Verbal Learning Test-Revised scores did not show significant difference across the three groups. Compared with no exposure group, the BVMT-R scores were slightly lower in the prenatal exposure group and markedly decreased in the infant exposure group. When the BVMT-R scores were analyzed in three subgroups, the results showed that the subjects whose mothers were exposed to earthquake in the second and third trimesters of pregnancy had significantly lower BVMT-R scores compared with those in the first trimester. Education level and early-life earthquake exposure were identified as independent risk factors for reduced performance of

  2. Long-term erosion and interglacial period exposure in Western Greenland from meteoric 10Be in ice-bound sediment

    Science.gov (United States)

    Graly, J. A.; Corbett, L.; Bierman, P. R.; Neumann, T.; Rood, D. H.; Finkel, R. C.

    2010-12-01

    To examine the history of surface exposure and erosion in areas of Western Greenland presently covered by ice, we measured the concentration of meteoric 10Be in ice-bound fine sediment at three locations: Kangerlussuaq (67.1°N), Ilulissat (69.4°N), and Upernavik (72.5°N). Meteoric 10Be concentrations at Ilulissat and Upernavik range from 2×106 to 2×108 atoms/g and are statistically indistinguishable from each other. Meteoric 10Be concentrations at Kangerlussuaq range from 2×106 to 5×107 atoms/g and are significantly lower than the values found at the northern two sites. Through comparison to typical meteoric 10Be distribution in soils, source soil ages can be estimated at each of these locations. These estimates suggest on the order of 105 years of exposure at the northern sites and on the order of 104 years of exposure at Kangerlussuaq. Because meteoric 10Be is lost from the soil system both by erosion and isotope decay, these exposure ages represent a minimum length of cumulative interglacial exposure. This exposure signal likely developed over several Late Pliocene and Pleistocene interglacial periods and prior to the onset of Northern hemisphere glaciation, ~2.7 Ma before present. To further constrain the glacial history of Western Greenland implied from the meteoric 10Be data, we constructed forward models of interglacial period exposure and glacial period erosion. The high levels of meteoric 10Be at Upernavik and Ilulissat imply erosion rates below 5 m/My and some preservation of pre-glacial regolith. The lower levels of meteoric 10Be at Kangerlussuaq can be explained with erosion rates as high as 20 m/My. Because of the substantial debris fluxes in modern Kangerlussuaq glaciers [Knight, et al., 2002], erosion rates greater than 10 m/My are likely. Meteoric 10Be inventories at Kangerlussuaq under 10-20 m/My of long-term erosion imply substantial interglacial exposure and the slow evacuation of sediment by glacial transport. These results suggest that

  3. The effect of long-term exposure to elevated CO2 on nitrogen gas emissions from Mojave Desert soils

    Science.gov (United States)

    McCalley, Carmody K.; Strahm, Brian D.; Sparks, Kimberlee L.; Eller, Allyson S. D.; Sparks, Jed P.

    2011-09-01

    In arid regions, emissions of nitrogen (N) gases are important to long-term soil fertility and regional atmospheric chemistry, making alterations in N gas emissions an important aspect of ecosystem response to climate change. Studies at the Nevada Desert FACE Facility suggest that rising atmospheric CO2 concentrations impact ecosystems N dynamics in the Mojave Desert; our objective was to identify whether those responses translate into changes in trace N gas emissions. We measured soil fluxes of reactive N gases (NO, NOy, NH3) and N2O in plots receiving long-term fumigation with ambient and elevated (550 ppm) CO2. Reactive N gas emissions were significantly lower under elevated CO2 during high soil moisture conditions in the spring and fall. The strongest responses occurred in the islands of fertility created by the dominant shrub Larrea tridentata, where fluxes were 3-5 ng N m-2 s-1 lower in elevated CO2 plots. Changes in total N gas emissions were driven by reduced NO and NH3 emissions, with smaller changes in NOy efflux and little to no production of N2O. Lower N gas emissions under elevated CO2 reflect changes in plant and microbial demand for N, suggesting increased uptake or immobilization coupled with decreased rates of N mineralization and nitrification. This response of N gas efflux to elevated CO2 in the growing season suggests that in deserts, elevated CO2 promotes ecosystem retention of N during periods of peak biological demand. Concomitantly, exposure to elevated CO2 alters inputs of new reactive gases into the atmosphere, potentially impacting local atmospheric processes.

  4. Association between long-term exposure to outdoor air pollution and mortality in China: a cohort study.

    Science.gov (United States)

    Cao, Jie; Yang, Chunxue; Li, Jianxin; Chen, Renjie; Chen, Bingheng; Gu, Dongfeng; Kan, Haidong

    2011-02-28

    No prior cohort studies exist in China examining the association of outdoor air pollution with mortality. We studied 70,947 middle-aged men and women in the China National Hypertension Survey and its follow-up study. Baseline data were obtained in 1991 using a standard protocol. The follow-up evaluation was conducted in 1999 and 2000. Annual average air pollution exposure between 1991 and 2000, including total suspended particle (TSP), sulfur dioxide (SO(2)) and nitrogen oxides (NO(x)), were estimated by linking fixed-site monitoring data with resident zip code. We examined the association of air pollution with mortality using proportional hazards regression model. We found significant associations between air pollution levels and mortality from cardiopulmonary diseases and from lung cancer. Each 10 μg/m(3) elevation of TSP, SO(2) and NO(x) was associated with a 0.9% (95%CI: 0.3%, 1.5%), 3.2% (95%CI: 2.3%, 4.0%), and 2.3% (95%CI: 0.6%, 4.1%) increased risk of cardiovascular mortality, respectively. We found significant effects of SO(2) on mortality after adjustment for TSP. Conclusively, ambient air pollution was associated with increased cardiopulmonary and lung cancer mortality in China. These data contribute to the scientific literature on long-term effects of air pollution for high exposure settings typical in developing countries.

  5. Effect of long-term cyanide exposure on cyanide-sensitive respiration and phosphate metabolism in the fungus Phycomyces blakesleeanus

    Directory of Open Access Journals (Sweden)

    Stanić Marina

    2014-01-01

    Full Text Available The effects of long-term exposure (5 h of Phycomyces blakesleeanus mycelium to 5 mM KCN on respiration and phosphate metabolites were tested. Exposure to cyanide, antimycin A and azide lead to a decrease in the activity of cyanide-sensitive respiration (CSR, and the ratio of core polyphosphates (PPc and inorganic phosphates (Pi, which is a good indicator of the metabolic state of a cell. After 5 h of incubation, the activity of CSR returned to control values. For this, the recovery of cytochrome c oxidase (COX was required. In addition, the PPc/Pi ratio started to recover shortly after initiation of COX recovery, but never reached control values. This led us to conclude that the regulation of polyphosphate (PPn levels in the cell is tightly coupled to respiratory chain functioning. In addition, acutely applied cyanide caused two different responses, observed by 31P NMR spectroscopy, that were probably mediated through the mechanism of glycolytic oscillations, triggered by the effect of cyanide on mitochondria. [Projekat Ministarstva nauke Republike Srbije, br. 173040

  6. Health impacts of long-term exposure to disinfection by-products in drinking water in Europe: HIWATE.

    Science.gov (United States)

    Nieuwenhuijsen, Mark J; Smith, Rachel; Golfinopoulos, Spyros; Best, Nicky; Bennett, James; Aggazzotti, Gabriella; Righi, Elena; Fantuzzi, Guglielmina; Bucchini, Luca; Cordier, Sylvaine; Villanueva, Cristina M; Moreno, Victor; La Vecchia, Carlo; Bosetti, Cristina; Vartiainen, Terttu; Rautiu, Radu; Toledano, Mireille; Iszatt, Nina; Grazuleviciene, Regina; Kogevinas, Manolis

    2009-06-01

    There appears to be very good epidemiological evidence for a relationship between chlorination by-products, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers, including colorectal cancer appears to be inconclusive and inconsistent. There appears to be some evidence for a relationship between chlorination by-products, as measured by THMs, and small for gestational age (SGA)/intrauterine growth retardation (IUGR) and preterm delivery, but evidence for other outcomes such as low birth weight (LBW), stillbirth, congenital anomalies and semen quality appears to be inconclusive and inconsistent.The overall aim of the HIWATE study is to investigate potential human health risks (e.g. bladder and colorectal cancer, premature births, SGA, semen quality, stillbirth, congenital anomalies) associated with long-term exposure to low levels of disinfectants (such as chlorine) and DBPs occurring in water for human consumption and use in the food industry. The study will comprise risk-benefit analyses including quantitative assessments of risk associated with microbial contamination of drinking water versus chemical risk and will compare alternative treatment options. The outcome will be improved risk assessment and better information for risk management. The work is divided into different topics (exposure assessment, epidemiology, risk assessment and management) and studies.

  7. In-situ strain analysis of potential habitat composites exposed to a simulated long-term lunar radiation exposure

    Science.gov (United States)

    Rojdev, Kristina; O'Rourke, Mary Jane E.; Hill, Charles; Nutt, Steven; Atwell, William

    2013-03-01

    NASA is studying the effects of long-term space radiation on potential multifunctional composite materials for habitats to better determine their characteristics in harsh space environments. Two epoxy-matrix composite materials were selected for the study and were mounted in a test stand that simulated the biaxial stresses of a pressure vessel wall. The samples in the test stand were exposed to radiation at fast (0.1478 krad/s) and slow (0.0139 krad/s) dose rates, and the strain and temperature were recorded during the exposure. During a fast dose rate exposure, negative strain was recorded, decreasing with time, an indication of matrix shrinkage. Given previous radiation studies of polymers, this is expected to be a result of radiation-induced crosslinking in the epoxy matrix. However, with a slow dose rate, the materials exhibited a positive strain that increased with time, corresponding to stretching of the materials. This result is consistent with scission or degradation of the matrix occurring, possibly due to oxidative degradation.

  8. Long term Exposure to Extremely Low Frequency Electromagnetic Field Affects Sex Hormones Level and Structure of Testis in Rats

    Directory of Open Access Journals (Sweden)

    T.S. Javadifar

    2012-01-01

    Full Text Available Extremely Low Frequency Electromagnetic Fields (ELFEMFs are produced by a variety of different sources. The aim of this study was to evaluate the influence of ELFEMF on function and structure of testis in rats. Experimental adult male Wistar rats were exposed to a 50 Hz ELFEMF, 1 MT (emitted from solenoid for 24 h daily during 135 days. The sham rats were subjected to sham exposure and the control rats were kept in animal room. In final, blood samples collected for the determination of the testosterone, LH and FSH concentration in the plasma. The testis was examined using light microscopy. Results showed that in EMF exposed group plasma concentration of testosterone was decreased (p<0.001, plasma LH concentration was increased (p<0.01 and FSH showed no significant changes which were accompanied by marked atrophy of seminiferous tubules and marked increase in interstitial connective tissue as well as Leydig cell hyperplasia. In conclusion, long term exposure to ELFEMF could have adverse effects on mammalian reproduction.

  9. Stress-related endocrinological and psychopathological effects of short- and long-term 50Hz electromagnetic field exposure in rats.

    Science.gov (United States)

    Szemerszky, Renáta; Zelena, Dóra; Barna, István; Bárdos, György

    2010-01-15

    It is believed that different electromagnetic fields do have beneficial and harmful biological effects. The aim of the present work was to study the long-term consequences of 50 Hz electromagnetic field (ELF-EMF) exposure with special focus on the development of chronic stress and stress-induced psychopathology. Adult male Sprague-Dawley rats were exposed to ELF-EMF (50 Hz, 0.5 mT) for 5 days, 8h daily (short) or for 4-6 weeks, 24h daily (long). Anxiety was studied in elevated plus maze test, whereas depression-like behavior of the long-treated group was examined in the forced swim test. Some days after behavioral examination, the animals were decapitated among resting conditions and organ weights, blood hormone levels as well as proopiomelanocortin mRNA level from the anterior lobe of the pituitary gland were measured. Both treatments were ineffective on somatic parameters, namely none of the changes characteristic to chronic stress (body weight reduction, thymus involution and adrenal gland hypertrophy) were present. An enhanced blood glucose level was found after prolonged ELF-EMF exposure (p=0.013). The hormonal stress reaction was similar in control and short-term exposed rats, but significant proopiomelanocortin elevation (pexposure. Taken together, long and continuous exposure to relatively high intensity electromagnetic field may count as a mild stress situation and could be a factor in the development of depressive state or metabolic disturbances. Although we should stress that the average intensity of the human exposure is normally much smaller than in the present experiment.

  10. Effects of repeated prenatal glucocorticoid exposure on long-term potentiation in the juvenile guinea-pig hippocampus.

    Science.gov (United States)

    Setiawan, Elaine; Jackson, Michael F; MacDonald, John F; Matthews, Stephen G

    2007-06-15

    Synthetic glucocorticoids (sGCs) are routinely used to treat women at risk of preterm labour to promote fetal lung maturation. There is now strong evidence that exposure to excess glucocorticoid during periods of rapid brain development has permanent consequences for endocrine function and behaviour in the offspring. Prenatal exposure to sGC alters the expression of N-methyl-D-aspartate receptor (NMDA-R) subunits in the fetal and neonatal hippocampus. Given the integral role of the NMDA-R in synaptic plasticity, we hypothesized that prenatal sGC exposure will have effects on hippocampal long-term potentiation (LTP) after birth. Further, this may occur in either the presence or absence of elevated cortisol concentrations, in vitro. Pregnant guinea-pigs were injected with betamethasone (Beta, 1 mg kg(-1)) or vehicle on gestational days (gd) 40, 41, 50, 51, 60 and 61 (term approximately 70 days), a regimen comparable to that given to pregnant women. On postnatal day 21, LTP was examined at Schaffer collateral synapses in the CA1 region of hippocampal slices prepared from juvenile animals exposed to betamethasone or vehicle, in utero. Subsequently, the acute glucocorticoid receptor (GR)- and mineralocorticoid receptor (MR)-dependent effects of cortisol (0.1-10 microM; bath applied 30 min before LTP induction) were examined. There was no effect of prenatal sGC treatment on LTP under basal conditions. The application of 10 microM cortisol depressed excitatory synaptic transmission in all treatment groups regardless of sex. Similarly, LTP was depressed by 10 microM cortisol in all groups, with the exception of Beta-exposed females, in which LTP was unaltered. Hippocampal MR and GR protein levels were increased in Beta-exposed females, but not in any other prenatal treatment group. This study reveals sex-specific effects of prenatal exposure to sGC on LTP in the presence of elevated cortisol, a situation that would occur in vivo during stress.

  11. Long-term Exposure to PM10 and NO2 in Association with Lung Volume and Airway Resistance in the MAAS Birth Cohort

    OpenAIRE

    2013-01-01

    Background: Findings from previous studies on the effects of air pollution exposure on lung function during childhood have been inconsistent. A common limitation has been the quality of exposure data used, and few studies have modeled exposure longitudinally throughout early life. Objectives: We sought to study the long-term effects of exposure to particulate matter with an aerodynamic diameter ≤ 10 μm (PM10) and to nitrogen dioxide (NO2) on specific airway resistance (sRaw) and forced expira...

  12. Effects of exposure to an extremely low frequency electromagnetic field on hippocampal long-term potentiation in rat.

    Science.gov (United States)

    Komaki, Alireza; Khalili, Afshin; Salehi, Iraj; Shahidi, Siamak; Sarihi, Abdolrahman

    2014-05-20

    Modern lifestyle exposes nearly all humans to electromagnetic fields, particularly to extremely low frequency electromagnetic fields (ELF-EMFs). Prolonged exposure to ELF-EMFs induces persistent changes in neuronal activity. However, the modulation of synaptic efficiency by ELF-EMFs in vivo is still unclear. In the present study, we investigated whether ELF-EMFs can change induction of long-term potentiation (LTP) and paired-pulse ratio (PPR) in the rat hippocampal area. Twenty-nine adult male Wistar rats were divided into 3 groups (ELF-EMF exposed, sham and control groups). The ELF-EMF group was exposed to a magnetic field for 90 consecutive days (2h/day). ELF-EMFs were produced by a circular coil (50Hz, 100 micro Tesla). The sham-exposed controls were placed in an identical chamber with no electromagnetic field. After this period, rats were deeply anesthetized with urethane (2.0mg/kg) and then a bipolar stimulating and recording electrode was implanted into the perforant pathway (PP) and dentate gyrus (DG), respectively. LTP in hippocampal area was induced by high-frequency stimulation (HFS). Prolonged exposure to ELF-EMFs increased LTP induction. There was a significant difference in the slope of EPSP and amplitude of PS between the ELF-EMF group and other groups. In conclusion, our data suggest that exposure to ELF-EMFs produces a marked change in the synaptic plasticity generated in synapses of the PP-DG. No significant difference in PPR of ELF-EMF group before and after HFS suggests a postsynaptic expression site of LTP.

  13. Exposure to Kynurenic Acid during Adolescence Increases Sign-tracking and Impairs Long-term Potentiation in Adulthood

    Directory of Open Access Journals (Sweden)

    Nicole eDeAngeli

    2015-01-01

    Full Text Available Changes in brain reward systems are thought to contribute significantly to the cognitive and behavioral impairments of schizophrenia, as well as the propensity to develop co-occurring substance abuse disorders. Presently there are few treatments for persons with a dual-diagnosis and little is known about the neural substrates that underlie co-occurring schizophrenia and substance abuse. One goal of the present study was to determine if a change in the concentration of kynurenic acid (KYNA, a tryptophan metabolite that is increased in the brains of people with schizophrenia, affects reward-related behavior. KYNA is an endogenous antagonist of NMDA glutamate receptors and α7 nicotinic acetylcholine receptors, both of which are critically involved in neurodevelopment, plasticity, and behavior. In Experiment 1, rats were treated throughout adolescence with l-kynurenine (L-KYN, the precursor of KYNA. As adults, the rats were tested drug-free in an autoshaping procedure in which a lever was paired with food. Rats treated with L-KYN during adolescence exhibited increased sign-tracking behavior (lever pressing when they were tested as adults. Sign-tracking is thought to reflect the lever acquiring incentive salience (motivational value as a result of its pairing with reward. Thus, KYNA exposure may increase the incentive salience of cues associated with reward, perhaps contributing to an increase in sensitivity to drug-related cues in persons with schizophrenia. In Experiment 2, we tested the effects of exposure to KYNA during adolescence on hippocampal long-term potentiation (LTP. Rats treated with L-KYN exhibited no LTP after a burst of high frequency stimulation that was sufficient to produce robust LTP in vehicle-treated rats. This finding represents the first demonstrated consequence of elevated KYNA concentration during development and provides insight into the basis for cognitive and behavioral deficits that result from exposure to KYNA during

  14. Long-term culture and differentiation of CNS precursors derived from anterior human neural rosettes following exposure to ventralizing factors

    Energy Technology Data Exchange (ETDEWEB)

    Colleoni, Silvia, E-mail: silviacolleoni@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Galli, Cesare [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Dipartimento Clinico Veterinario, Universita di Bologna, Via Tolara di Sopra 50, 40064 Ozzano Emilia (Italy); Giannelli, Serena G. [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Armentero, Marie-Therese; Blandini, Fabio [Laboratory of Functional Neurochemistry, Interdepartmental Research Center for Parkinson' s Disease, Neurological Institute C. Mondino, Via Mondino 2, 27100 Pavia (Italy); Broccoli, Vania, E-mail: broccoli.vania@hsr.it [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Lazzari, Giovanna, E-mail: giovannalazzari@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy)

    2010-04-15

    In this study we demonstrated that neural rosettes derived from human ES cells can give rise either to neural crest precursors, following expansion in presence of bFGF and EGF, or to dopaminergic precursors after exposure to ventralizing factors Shh and FGF8. Both regionalised precursors are capable of extensive proliferation and differentiation towards the corresponding terminally differentiated cell types. In particular, peripheral neurons, cartilage, bone, smooth muscle cells and also pigmented cells were obtained from neural crest precursors while tyrosine hydroxylase and Nurr1 positive dopaminergic neurons were derived from FGF8 and Shh primed rosette cells. Gene expression and immunocytochemistry analyses confirmed the expression of dorsal and neural crest genes such as Sox10, Slug, p75, FoxD3, Pax7 in neural precursors from bFGF-EGF exposed rosettes. By contrast, priming of rosettes with FGF8 and Shh induced the expression of dopaminergic markers Engrailed1, Pax2, Pitx3, floor plate marker FoxA2 and radial glia markers Blbp and Glast, the latter in agreement with the origin of dopaminergic precursors from floor plate radial glia. Moreover, in vivo transplant of proliferating Shh/FGF8 primed precursors in parkinsonian rats demonstrated engraftment and terminal dopaminergic differentiation. In conclusion, we demonstrated the derivation of long-term self-renewing precursors of selected regional identity as potential cell reservoirs for cell therapy applications, such as CNS degenerative diseases, or for the development of toxicological tests.

  15. Long-term exposure to elevated CO2 and O3 alters aspen foliar chemistry across developmental stages.

    Science.gov (United States)

    Couture, J J; Holeski, L M; Lindroth, R L

    2014-03-01

    Anthropogenic activities are altering levels of greenhouse gases to the extent that multiple and diverse ecosystem processes are being affected. Two gases that substantially influence forest health are atmospheric carbon dioxide (CO2 ) and tropospheric ozone (O3 ). Plant chemistry will play an important role in regulating ecosystem processes in future environments, but little information exists about the longitudinal effects of elevated CO2 and O3 on phytochemistry, especially for long-lived species such as trees. To address this need, we analysed foliar chemical data from two genotypes of trembling aspen, Populus tremuloides, collected over 10 years of exposure to levels of CO2 and O3 predicted for the year 2050. Elevated CO2 and O3 altered both primary and secondary chemistry, and the magnitude and direction of the responses varied across developmental stages and between aspen genotypes. Our findings suggest that the effects of CO2 and O3 on phytochemical traits that influence forest processes will vary over tree developmental stages, highlighting the need to continue long-term, experimental atmospheric change research.

  16. Long-term monitoring of the onboard aircraft exposure level with a Si-diode based spectrometer.

    Science.gov (United States)

    Spurny, F; Dachev, Ts

    2003-01-01

    The radiation fields onboard aircraft are complex (EURADOS, 1996), and several methods are used to characterise them for radiation protection. We have tested a spectrometer based on Si-diode at different sources and accelerator facilities. The energy deposited in the diode is analysed to estimate the contribution of different radiations to dosimetry quantities. The spectrum of energy deposition events onboard aircraft is similar to that registered in the CERN high-energy reference field. We used this similarity to determine the correction factors to appreciate radiation protection quantities from the results of onboard measurements. During 2001-2002, the spectrometer was used to acquire measurements onboard commercial aircraft during five long-term exposures. All necessary flight parameters were acquired; thus permitting calculations of the onboard effective dose and/or ambient dose equivalent by means of both the CARI 6 and the EPCARD codes and comparison with the results of the measurements. It was found that the apparent ambient dose equivalent values from measured data are in reasonable agreement with the results of calculations. Quantitative analysis of this agreement as a function of flight parameters (geomagnetic position, solar activity variations, etc.) is presented. During one flight, an important solar event (GLE 60 on 15 April 2001) was recorded by the spectrometer. In some other cases the measurements during a Forbush decreases were acquired. These extremes were well registered by the equipment and the data obtained are analyzed.

  17. Chronic interstitial fibrosis in the rat kidney induced by long-term (6-mo) exposure to lithium.

    Science.gov (United States)

    Walker, Robert J; Leader, John P; Bedford, Jennifer J; Gobe, Glenda; Davis, Gerard; Vos, Frederiek E; deJong, Sylvia; Schollum, John B W

    2013-02-01

    There is a lack of suitable animal models that replicate the slowly progressive chronic interstitial fibrosis that is characteristic of many human chronic nephropathies. We describe a chronic long-term (6-mo) model of lithium-induced renal fibrosis, with minimal active inflammation, which mimics chronic kidney interstitial fibrosis seen in the human kidney. Rats received lithium via their chow (60 mmol lithium/kg food) daily for 6 mo. No animals died during the exposure. Nephrogenic diabetes insipidus was established by 3 wk and persisted for the 6 mo. Following metabolic studies, the animals were killed at 1, 3, and 6 mo and the kidneys were processed for histological and immunohistochemical studies. Progressive interstitial fibrosis, characterized by increasing numbers of myofibroblasts, enhanced transforming growth factor-β(1) expression and interstitial collagen deposition, and a minimal inflammatory cellular response was evident. Elucidation of the underlying mechanisms of injury in this model will provide a greater understanding of chronic interstitial fibrosis and allow the development of intervention strategies to prevent injury.

  18. Influence of minerals on lead-induced alterations in liver function in rats exposed to long-term lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D' souza Sunil, E-mail: hermansdsouza@rediffmail.com [Department of Biotechnology, Manipal Life Sciences Centre, KMC, Manipal University, Manipal (India); Geraldine, Menezes, E-mail: gere1@rediffmail.com [Department of Biochemistry and Biophysics, St. John' s Medical College, Koramangala, Bangalore 560034, Karnataka (India); T, Venkatesh, E-mail: venky_tv@hotmail.com [Department of Biochemistry and Biophysics, St. John' s Medical College, Koramangala, Bangalore 560034, Karnataka (India)

    2009-07-30

    The objective of this study was to evaluate the role of minerals on lead-induced effect on the liver. Differentiation of minerals and heavy metals pose an inherent problem due to certain common properties shared by them. With this approach to the problem of heavy metal toxicity, in the present study two groups of male Wistar albino rats, one group (well-nourished) fed on mineral rich diet and other group (undernourished) fed on diet without mineral supplements were used. Both the groups of rats were subjected to long-term lead exposure. The diet of well-nourished group was supplemented with calcium (Ca); 1.2%, phosphorous (P); 0.6%, iron (Fe); 90 mg/kg, zinc (Zn); 50 mg/kg, magnesium (Mg); 0.08%, manganese (Mn); 70 mg/kg, selenium (Se); 0.2 mg/kg, copper (Cu); 5 mg/kg, molybdenum (Mo); 0.8 mg/kg, iodine (I); 0.6 mg/kg, cobalt (Co); 3.0 mg/kg. Their blood lead and parameters of liver function were monitored periodically. Results of the study showed a very high statistically significant increase (p < 0.001) in the blood lead (PbB) levels and liver function test parameters in the undernourished subjects compared to the well-nourished subjects. Nutritional management of lead poisoning is of importance since essential elements and toxic heavy metals may interact to minimize the absorption of lead.

  19. Effects of long-term ambient ozone exposure on biomass and wood traits in poplar treated with ethylenediurea (EDU).

    Science.gov (United States)

    Carriero, G; Emiliani, G; Giovannelli, A; Hoshika, Y; Manning, W J; Traversi, M L; Paoletti, E

    2015-11-01

    This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

  20. [Autoimmune processes after long-term low-level exposure to electromagnetic fields (the results of an experiment). Part 2. General scheme and conditions of the experiment. Development of RF exposure conditions complying with experimental tasks. Animal's status during the long-term exposure].

    Science.gov (United States)

    Grigor'ev, Iu G; Grigor'ev, O A; Merkulov, A V; Shafirkin, A V; Vorob'ev, A A

    2010-01-01

    This paper describes the conditions for handling and exposure of experimental animals (Wistar rats) and methods used in the study of immunological effects of long-term low-level (500 microW/cm2) exposure to radiofrequency (2450 MHz) electromagnetic fields, performed under auspices of the World Health Organization.

  1. Environmental effects of poly(phenylene ether) blends after long-term exposure to potable hot water

    Science.gov (United States)

    Maclean, Steven

    In recent years, engineering thermoplastic resins have been contemplated for use in a variety pressurized fluid handling components such as potable water delivery pipes, fitting and valves. In this research, rigid blends of glassy poly(phenylene ether) (PPE) polymer are studied to assess their suitability in long-term, potable, hot water environments. Three distinct PPE-based model compounds were prepared for this research: (i) a 50/50 blend of PPE and high impact polystyrene (HIPS); (ii) a 50/50 blend of PPE and HIPS with the inclusion of an anti-oxidant package and; (iii) a blend consisting of capped PPE, crystal polystyrene and styrene-ethyelene-butylene-styrene (SEBS) rubber. A fourth engineering thermoplastic, namely bisphenol-A polysulfone (PSU), was incorporated into the study as a benchmark material due to its proven reliability in hot water applications. Aging experiments were carried out for 8,000 hours in an 80°C water bath and an 80°C convection oven to characterize physical property retention and degradation mechanisms in each material. During water bath immersion, excessive, non-Fickian water diffusion occurred in both PPE/HIPS blends which led to water clustering and disc shaped microcavities on the order of 50 to 100 mum in diameter. These voids in the bulk caused appreciable losses in tensile elongation and fatigue resistance. The capped PPE/PS/SEBS blend, however, managed water uptake more effectively and its chemistry deterred water clustering. With further improvements to the formulation, such as larger rubber domains or an alternative impact modifier, the capped PPE blend may be able to offer physical property retention equal to that of PSU. With the exception of slight craze formation at sharp specimen edges during hot water immersion, the PSU material proved to be an exceptional material candidate throughout the entire experimentation. Surprisingly long-term hot water exposure did not cause gross chemical degradation in any of the materials

  2. An examination of population exposure to traffic related air pollution: Comparing spatially and temporally resolved estimates against long-term average exposures at the home location.

    Science.gov (United States)

    Shekarrizfard, Maryam; Faghih-Imani, Ahmadreza; Hatzopoulou, Marianne

    2016-05-01

    Air pollution in metropolitan areas is mainly caused by traffic emissions. This study presents the development of a model chain consisting of a transportation model, an emissions model, and atmospheric dispersion model, applied to dynamically evaluate individuals' exposure to air pollution by intersecting daily trajectories of individuals and hourly spatial variations of air pollution across the study domain. This dynamic approach is implemented in Montreal, Canada to highlight the advantages of the method for exposure analysis. The results for nitrogen dioxide (NO2), a marker of traffic related air pollution, reveal significant differences when relying on spatially and temporally resolved concentrations combined with individuals' daily trajectories compared to a long-term average NO2 concentration at the home location. We observe that NO2 exposures based on trips and activity locations visited throughout the day were often more elevated than daily NO2 concentrations at the home location. The percentage of all individuals with a lower 24-hour daily average at home compared to their 24-hour mobility exposure is 89.6%, of which 31% of individuals increase their exposure by more than 10% by leaving the home. On average, individuals increased their exposure by 23-44% while commuting and conducting activities out of home (compared to the daily concentration at home), regardless of air quality at their home location. We conclude that our proposed dynamic modelling approach significantly improves the results of traditional methods that rely on a long-term average concentration at the home location and we shed light on the importance of using individual daily trajectories to understand exposure.

  3. Surrogates of Long-Term Vitamin D Exposure and Ovarian Cancer Risk in Two Prospective Cohort Studies

    Energy Technology Data Exchange (ETDEWEB)

    Prescott, Jennifer, E-mail: jennifer.prescott@channing.harvard.edu; Bertrand, Kimberly A.; Poole, Elizabeth M.; Rosner, Bernard A.; Tworoger, Shelley S. [Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, 181 Longwood Ave. Boston, MA 02115 (United States)

    2013-11-22

    Experimental evidence and ecologic studies suggest a protective role of vitamin D in ovarian carcinogenesis. However, epidemiologic studies using individual level data have been inconsistent. We evaluated ultraviolet (UV)-B radiation, vitamin D intake, and predicted plasma 25-hydroxyvitamin D [25(OH)D] levels as long-term surrogates of vitamin D exposure within the Nurses’ Health Study (NHS) and NHSII. We estimated incidence rate ratios (RRs) and 95% confidence intervals (CIs) for risk of overall ovarian cancer and by histologic subtype using Cox proportional hazards models. Between 1976 and 2010 in NHS and 1989 and 2011 in NHSII, we identified a total of 1,225 incident epithelial ovarian cancer cases (NHS: 970, NHSII: 255) over 4,628,648 person-years of follow-up. Cumulative average UV-B exposure was not associated with ovarian cancer risk in NHS (P{sub trend} = 0.08), but was associated with reduced risk in NHSII (highest vs. lowest category RR = 0.67; 95% CI: 0.50, 0.89; P{sub trend} < 0.01). When stratified by histologic subtype, UV-B flux was positively associated with risk of serous tumors in NHS (P{sub trend} < 0.01), but inversely associated in NHSII (P{sub trend} = 0.01). Adjusted for confounders, ovarian cancer risk was not associated with vitamin D intake from food or supplements or with predicted 25(OH)D levels. Our study does not strongly support a protective role for vitamin D in ovarian cancer risk.

  4. [The effect of long-term exposure to low doses of endocrine disruptor ddt on serum levels of thyroid protein autoantigenes and antithyroid autoantibodies].

    Science.gov (United States)

    Yaglova, N V; Yaglov, V V

    2016-01-01

    Changes in secretion of thyroid autoantigenes and production of antithyroid autoantibodies after long-term exposure to low doses of DDT were studied. Changes in serum levels of antithyroid peroxidase antibodies and thyroid peroxidase, attributed to disruption of thyroxine production by DDT were found. Long-term exposure of rats to low doses of DDT revealed no specific impact on serum autoantibodies to all thyroid autoantigenes studied. The increase of the ratio of autoantibody/autoantigen for thyroid peroxidase and thyroglobulin was rather small and thus could not be considered as a significant symptom of thyroid autoimmunity.

  5. Long-term exposure to ambient ozone and mortality: a quantitative systematic review and meta-analysis of evidence from cohort studies.

    Science.gov (United States)

    Atkinson, R W; Butland, B K; Dimitroulopoulou, C; Heal, M R; Stedman, J R; Carslaw, N; Jarvis, D; Heaviside, C; Vardoulakis, S; Walton, H; Anderson, H R

    2016-02-23

    While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality. Cohort studies published in peer-reviewed journals indexed in EMBASE and MEDLINE to September 2015 and PubMed to October 2015 and cited in reviews/key publications were identified via search strings using terms relating to study design, pollutant and health outcome. Study details and estimate information were extracted and used to calculate standardised effect estimates expressed as HRs per 10 ppb increment in long-term ozone concentrations. 14 publications from 8 cohorts presented results for ozone and all-cause and cause-specific mortality. We found no evidence of associations between long-term annual O3 concentrations and the risk of death from all causes, cardiovascular or respiratory diseases, or lung cancer. 4 cohorts assessed ozone concentrations measured during the warm season. Summary HRs for cardiovascular and respiratory causes of death derived from 3 cohorts were 1.01 (95% CI 1.00 to 1.02) and 1.03 (95% CI 1.01 to 1.05) per 10 ppb, respectively. Our quantitative review revealed a paucity of independent studies regarding the associations between long-term exposure to ozone and mortality. The potential impact of climate change and increasing anthropogenic emissions of ozone precursors on ozone levels worldwide suggests further studies of the long-term effects of exposure to high ozone levels are warranted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. Long-term monitoring of air crew exposure onboard of Czech Airlines aircraft; Monitorage a long terme de l'exposition du personnel navigant a bord d'un avion de la compagnie aerienne Czech Airlines

    Energy Technology Data Exchange (ETDEWEB)

    Ploc, O.; Spurny, F. [Nuclear Physics Institute AS CR, Dept. of Radiation Dosimetry, Prague (Czech Republic); Ploc, O. [Czech Technical Univ., Dept. of Dosimetry and Application of Ionizing Radiation, Prague (Czech Republic)

    2007-01-15

    This contribution presents new results related to the aircraft crew exposure onboard aircraft of Czech air companies. First, the results of long term monitoring onboard of an aircraft of Czech Airlines are presented. In the period May-December 2005, 494 individual flights have been followed using MDU-Liulin Si-diode based spectrometer, together with thermoluminescent and track detectors. The results of measurements are analyzed and compared with those of calculation performed with CARI6 and EPCARD3.2 codes. Monitoring period represented about 4.6 times more than usual annual engagement of an aircrew (600 hours). Total effective dose during these 2 755 hours was between Il and 12 mSv, following the considered method of evaluation. Both the measuring and calculation methods correlate well. This fact leads to confirmation of the routine method evaluating the level of aircraft crew exposure using CARI6 code as correct for this purpose. Second, the results of individual monitoring of aircrew members obtained during few last years by this routine method are presented; general tendencies of aircraft crew onboard exposure of Czech air companies are outlined. The contribution of aircrew exposure to total occupational exposure in the Czech Republic represents about 20%. (authors)

  7. Quantification of long-term erosion rates from root exposure/tree age relationships in an alpine meadow catchment

    Science.gov (United States)

    Scuderi, Louis A.

    2017-04-01

    Erosion rates derived using dendrogeomorphology have been used to quantify slope degradation in many localities globally. However, with the exception of the western United States, most of these estimates are derived from short-lived trees whose lifetimes may not adequately reflect the complete range of slope processes which can include erosion, deposition, impacts of extreme events and even long-term hiatuses. Erosion rate estimates at a given site using standard techniques therefore reflect censored local point erosion estimates rather than long-term rates. We applied a modified dendrogeomorphic approach to rapidly estimate erosion rates from dbh/age relationships to assess the difference between short and long-term rates and found that the mean short-term rate was 0.13 cm/yr with high variability, while the uncensored long-term rate was 0.06 cm/yr. The results indicate that rates calculated from short-lived trees, while possibly appropriate for local short-term point estimates of erosion, are highly variable and may overestimate regional long-term rates by > 50%. While these findings do not invalidate the use of dendrogeomorphology to estimate erosion rates they do suggest that care must be taken to select older trees that incorporate a range of slope histories in order to best approximate regional long-term rates.

  8. Radioresistant cell strain of human fibrosarcoma cells obtained after long-term exposure to X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Wei, K.; Kodym, R. [Univ. of Vienna (Austria). Department of Radiotherapy and Radiobiology; Jin Cuizheng [Institute of Radiation Medicine, Beijing (China)

    1998-07-01

    A radioresistant cell strain from human fibrosarcoma HT1080 has been obtained after prolonged exposure to x-rays for 7 months (2 Gy per day, 5 days per week). This new strain, HT1080R, differs from HT1080 in a significantly increased ability of clonogenical survival, with coefficient {alpha} decreasing from 0.161 to 0.123 Gy{sup -1} and coefficient {beta} decreasing from 0.0950 to 0.0565 Gy{sup -2}. Furthermore, the radioresistance of HT1080R proved to be stable in long-term passaged cultures as well as in frozen samples. Differences between the two cell lines are also observed in the G-banded karyotype; the new cell line shows monosomy of chromosome 17 and loss of 5p{sup +} and 11q{sup +} present in the parental cells. These data suggest that the radioresistance may have been caused by radiation-induced cell mutation and that the resistant cells may have been selected by repeated irradiations. In order to characterize this new strain, the ability of the cells to rejoin DNA double-strand breaks, the cell cycle distribution and the amount of apoptosis after irradiation have been estimated; however, no differences are observed between these two cell strains. Although the mechanism of the elevated radioresistance remains unknown, this pair of cell strains can provide a new model system for further investigations with regard to the mechanisms of cellular radioresistance. The results also show that any type of irradiation similar to the schedules used in radiotherapy can lead to the formation and selection of more radioresistant cell clones in vitro, a phenomenon with possible implications for radiotherapy. (orig.) With 3 figs., 1 tab., 13 refs.

  9. Effects of long-term exposure to traffic-related air pollution on respiratory and cardiovascular mortality in the Netherlands: the NLCS-AIR study.

    NARCIS (Netherlands)

    Brunekreef, B.; Beelen, R.M.J.; Hoek, G.; Schouten, L.J.; Bausch-Goldbohm, S.; Fischer, P.; Armstrong, B.; Hughes, E.; Jerrett, M.; v.d. Brandt, P.A.

    2009-01-01

    Evidence is increasing that long-term exposure to ambient air pollution is associated with deaths from cardiopulmonary diseases. In a 2002 pilot study, we reported clear indications that traffic-related air pollution, especially at the local scale, was related to cardiopulmonary mortality in a rando

  10. DEVELOPMENTAL LEAD (PB) EXPOSURE REDUCES THE ABILITY OF THE NNDA ANTAGONIST MK801 TO SUPPRESS LONG-TERM POTENTIATION (LTP) IN THE RAT DENTATE GYRUS, IN VIVO

    Science.gov (United States)

    Chronic developmental lead (Pb) exposure increases the threshold and enhances decay of long-term potentiation (LTP) in the dentate gyrus of the hippocampal formation. MK-801 and other antagonists of the N-methyl-D-aspartate (NMDA) glutamate receptor subtype impair induction of LT...

  11. Associations between Long-Term Air Pollutant Exposures and Blood Pressure in Elderly Residents of Taipei City: A Cross-Sectional Study

    NARCIS (Netherlands)

    Chen, Szu-Ying; Wu, Chang-Fu; Lee, Jui-Huan; Hoffmann, Barbara; Peters, Annette; Brunekreef, Bert|info:eu-repo/dai/nl/067548180; Chu, Da-Chen; Chan, Chang-Chuan

    2015-01-01

    BACKGROUND: Limited information is available regarding long-term effects of air pollution on blood pressure (BP) and hypertension. OBJECTIVE: We studied whether 1-year exposures to particulate matter (PM) and nitrogen oxides (NOx) were correlated with BP and hypertension in the elderly. METHODS: We

  12. Microbial adhesion to surface-grafted polyacrylamide brushes after long-term exposure to PBS and reconstituted freeze-dried saliva

    NARCIS (Netherlands)

    Fundeanu, Irina; van der Mei, Henny C.; Schouten, Arend J.; Busscher, Henk J.

    2010-01-01

    Polyacrylamide (PAAm) brushes, covalently grafted from silicon wafer surfaces were examined for their ability to inhibit microbial adhesion after long-term exposure to PBS or reconstituted freeze-dried saliva for time intervals from 48 h up to 1 month at 37 degrees C. Microbial adhesion after

  13. Natural-cause mortality and long-term exposure to particle components : An Analysis of 19 European cohorts within the multi-center ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob; Hoek, Gerard; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul H.; Nieuwenhuijsen, Mark J.; Xun, Wei W.; Katsouyanni, Klea; Dimakopoulou, Konstantina; Marcon, Alessandro; Vartiainen, Erkki; Lanki, Timo; Yli-Tuomi, Tarja; Oftedal, Bente; Schwarze, Per E.; Nafstad, Per; de Faire, Ulf; Pedersen, Nancy L.; Östenson, Claes Göran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Göran; Eriksen, Kirsten Thorup; Overvad, Kim; Sørensen, Mette; Eeftens, Marloes; Peeters, Petra H.; Meliefste, Kees; Wang, Meng; Bas Bueno-De-Mesquita, H.; Sugiri, Dorothea; Krämer, Ursula; Heinrich, Joachim; De Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Jaensch, Andrea; Ineichen, Alex; Tsai, Ming Yi; Schaffner, Emmanuel; Probst-Hensch, Nicole M.; Schindler, Christian; Ragettli, Martina S.; Vilier, Alice; Clavel-Chapelon, Françoise; Declercq, Christophe; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Katsoulis, Michail; Trichopoulou, Antonia; Keuken, Menno; Jedynska, Aleksandra; Kooter, Ingeborg M.; Kukkonen, Jaakko; Sokhi, Ranjeet S.; Vineis, Paolo; Brunekreef, Bert

    2015-01-01

    Background: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. oBjectives: Our aim was to study the association between

  14. Natural-cause mortality and long-term exposure to particle components: An Analysis of 19 European cohorts within the multi-center ESCAPE project

    NARCIS (Netherlands)

    Beelen, R.; Hoek, G.; Raaschou-Nielsen, O.; Stafoggia, M.; Andersen, Z.J.; Weinmayr, G.; Hoffmann, B.; Wolf, K.; Samoli, E.; Fischer, P.H.; Nieuwenhuijsen, M.J.; Xun, W.W.; Katsouyanni, K.; Dimakopoulou, K.; Marcon, A.; Vartiainen, E.; Lanki, T.; Yli-Tuomi, T.; Oftedal, B.; Schwarze, P.E.; Nafstad, P.; de Faire, U.; Pedersen, N.L.; Östenson, C.-G.; Fratiglioni, L.; Penell, J.; Korek, M.; Pershagen, G.; Eriksen, K.T.; Overvad, K.; Sørensen, M.; Eeftens, M.; Peeters, P.H.; Meliefste, K.; Wang, M.; Bas Bueno-De-Mesquita, H.; Sugiri, D.; Krämer, U.; Heinrich, J.; De Hoogh, K.; Key, T.; Peters, A.; Hampel, R.; Concin, H.; Nagel, G.; Jaensch, A.; Ineichen, A.; Tsai, M.-Y.; Schaffner, E.; Probst-Hensch, N.M.; Schindler, C.; Ragettli, M.S.; Vilier, A.; Clavel-Chapelon, F.; Declercq, C.; Ricceri, F.; Sacerdote, C.; Galassi, C.; Migliore, E.; Ranzi, A.; Cesaroni, G.; Badaloni, C.; Forastiere, F.; Katsoulis, M.; Trichopoulou, A.; Keuken, M.; Jedynska, A.; Kooter, I.M.; Kukkonen, J.; Sokhi, R.S.; Vineis, P.; Brunekreef, B.

    2015-01-01

    Background: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. oBjectives: Our aim was to study the association between

  15. Natural-cause mortality and long-term exposure to particle components : an analysis of 19 European cohorts within the multi-center ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob|info:eu-repo/dai/nl/30483100X; Hoek, Gerard|info:eu-repo/dai/nl/069553475; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul H; Nieuwenhuijsen, Mark J; Xun, Wei W; Katsouyanni, Klea; Dimakopoulou, Konstantina; Marcon, Alessandro; Vartiainen, Erkki; Lanki, Timo; Yli-Tuomi, Tarja; Oftedal, Bente; Schwarze, Per E; Nafstad, Per; De Faire, Ulf; Pedersen, Nancy L; Östenson, Claes-Göran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Göran; Eriksen, Kirsten Thorup; Overvad, Kim; Sørensen, Mette; Eeftens, Marloes|info:eu-repo/dai/nl/315028300; Peeters, Petra H; Meliefste, Kees; Wang, Meng; Bueno-de-Mesquita, H Bas; Sugiri, Dorothea; Krämer, Ursula; Heinrich, Joachim; de Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Jaensch, Andrea; Ineichen, Alex; Tsai, Ming-Yi; Schaffner, Emmanuel; Probst-Hensch, Nicole M; Schindler, Christian; Ragettli, Martina S; Vilier, Alice; Clavel-Chapelon, Françoise; Declercq, Christophe; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Katsoulis, Michail; Trichopoulou, Antonia; Keuken, Menno; Jedynska, Aleksandra; Kooter, Ingeborg M; Kukkonen, Jaakko; Sokhi, Ranjeet S; Vineis, Paolo; Brunekreef, Bert|info:eu-repo/dai/nl/067548180

    BACKGROUND: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. OBJECTIVES: Our aim was to study the association between

  16. Natural-cause mortality and long-term exposure to particle components : An Analysis of 19 European cohorts within the multi-center ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob; Hoek, Gerard; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul H.; Nieuwenhuijsen, Mark J.; Xun, Wei W.; Katsouyanni, Klea; Dimakopoulou, Konstantina; Marcon, Alessandro; Vartiainen, Erkki; Lanki, Timo; Yli-Tuomi, Tarja; Oftedal, Bente; Schwarze, Per E.; Nafstad, Per; de Faire, Ulf; Pedersen, Nancy L.; Östenson, Claes Göran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Göran; Eriksen, Kirsten Thorup; Overvad, Kim; Sørensen, Mette; Eeftens, Marloes; Peeters, Petra H.; Meliefste, Kees; Wang, Meng; Bas Bueno-De-Mesquita, H.; Sugiri, Dorothea; Krämer, Ursula; Heinrich, Joachim; De Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Jaensch, Andrea; Ineichen, Alex; Tsai, Ming Yi; Schaffner, Emmanuel; Probst-Hensch, Nicole M.; Schindler, Christian; Ragettli, Martina S.; Vilier, Alice; Clavel-Chapelon, Françoise; Declercq, Christophe; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Katsoulis, Michail; Trichopoulou, Antonia; Keuken, Menno; Jedynska, Aleksandra; Kooter, Ingeborg M.; Kukkonen, Jaakko; Sokhi, Ranjeet S.; Vineis, Paolo; Brunekreef, Bert

    2015-01-01

    Background: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. oBjectives: Our aim was to study the association between natural-ca

  17. Natural-cause mortality and long-term exposure to particle components : an analysis of 19 European cohorts within the multi-center ESCAPE project

    NARCIS (Netherlands)

    Beelen, Rob; Hoek, Gerard; Raaschou-Nielsen, Ole; Stafoggia, Massimo; Andersen, Zorana Jovanovic; Weinmayr, Gudrun; Hoffmann, Barbara; Wolf, Kathrin; Samoli, Evangelia; Fischer, Paul H; Nieuwenhuijsen, Mark J; Xun, Wei W; Katsouyanni, Klea; Dimakopoulou, Konstantina; Marcon, Alessandro; Vartiainen, Erkki; Lanki, Timo; Yli-Tuomi, Tarja; Oftedal, Bente; Schwarze, Per E; Nafstad, Per; De Faire, Ulf; Pedersen, Nancy L; Östenson, Claes-Göran; Fratiglioni, Laura; Penell, Johanna; Korek, Michal; Pershagen, Göran; Eriksen, Kirsten Thorup; Overvad, Kim; Sørensen, Mette; Eeftens, Marloes; Peeters, Petra H; Meliefste, Kees; Wang, Meng; Bueno-de-Mesquita, H Bas; Sugiri, Dorothea; Krämer, Ursula; Heinrich, Joachim; de Hoogh, Kees; Key, Timothy; Peters, Annette; Hampel, Regina; Concin, Hans; Nagel, Gabriele; Jaensch, Andrea; Ineichen, Alex; Tsai, Ming-Yi; Schaffner, Emmanuel; Probst-Hensch, Nicole M; Schindler, Christian; Ragettli, Martina S; Vilier, Alice; Clavel-Chapelon, Françoise; Declercq, Christophe; Ricceri, Fulvio; Sacerdote, Carlotta; Galassi, Claudia; Migliore, Enrica; Ranzi, Andrea; Cesaroni, Giulia; Badaloni, Chiara; Forastiere, Francesco; Katsoulis, Michail; Trichopoulou, Antonia; Keuken, Menno; Jedynska, Aleksandra; Kooter, Ingeborg M; Kukkonen, Jaakko; Sokhi, Ranjeet S; Vineis, Paolo; Brunekreef, Bert

    2015-01-01

    BACKGROUND: Studies have shown associations between mortality and long-term exposure to particulate matter air pollution. Few cohort studies have estimated the effects of the elemental composition of particulate matter on mortality. OBJECTIVES: Our aim was to study the association between natural-ca

  18. Corrosion of metals in wood : comparing the results of a rapid test method with long-term exposure tests across six wood treatments

    Science.gov (United States)

    Samuel L. Zelinka; Donald S. Stone

    2011-01-01

    This paper compares two methods of measuring the corrosion of steel and galvanized steel in wood: a long-term exposure test in solid wood and a rapid test method where fasteners are electrochemically polarized in extracts of wood treated with six different treatments. For traditional wood preservatives, the electrochemical extract method correlates with solid wood...

  19. Enhancement of cancer stem-like and epithelial−mesenchymal transdifferentiation property in oral epithelial cells with long-term nicotine exposure: Reversal by targeting SNAIL

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Cheng-Chia [Institute of Oral Science, Chung Shan Medical University, Taichung, Taiwan (China); School of Dentistry, Chung Shan Medical University, Taichung, Taiwan (China); Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Chang, Yu-Chao, E-mail: cyc@csmu.edu.tw [School of Dentistry, Chung Shan Medical University, Taichung, Taiwan (China); Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan (China)

    2013-02-01

    Cigarette smoking is one of the major risk factors in the development and further progression of tumorigenesis, including oral squamous cell carcinoma (OSCC). Recent studies suggest that interplay cancer stem-like cells (CSCs) and epithelial−mesenchymal transdifferentiation (EMT) properties are responsible for the tumor maintenance and metastasis in OSCC. The aim of the present study was to investigate the effects of long-term exposure with nicotine, a major component in cigarette, on CSCs and EMT characteristics. The possible reversal regulators were further explored in nicotine-induced CSCs and EMT properties in human oral epithelial (OE) cells. Long-term exposure with nicotine was demonstrated to up-regulate ALDH1 population in normal gingival and primary OSCC OE cells dose-dependently. Moreover, long-term nicotine treatment was found to enhance the self-renewal sphere-forming ability and stemness gene signatures expression and EMT regulators in OE cells. The migration/cell invasiveness/anchorage independent growth and in vivo tumor growth by nude mice xenotransplantation assay was enhanced in long-term nicotine-stimulated OE cells. Knockdown of Snail in long-term nicotine-treated OE cells was found to reduce their CSCs properties. Therapeutic delivery of Si-Snail significantly blocked the xenograft tumorigenesis of long-term nicotine-treated OSCC cells and largely significantly improved the recipient survival. The present study demonstrated that the enrichment of CSCs coupled EMT property in oral epithelial cells induced by nicotine is critical for the development of OSCC tumorigenesis. Targeting Snail might offer a new strategy for the treatment of OSCC patients with smoking habit. -- Highlights: ► Sustained nicotine treatment induced CSCs properties of oral epithelial cells. ► Long-term nicotine treatment enhance EMT properties of oral epithelial cells. ► Long-term nicotine exposure increased tumorigenicity of oral epithelial cells. ► Si

  20. Augmentation of Endoxifen Exposure in Tamoxifen-Treated Women Following SSRI Switch

    NARCIS (Netherlands)

    L. Binkhorst (Lisette); M. Bannink (Marjolein); P. de Bruijn (Peter); J.B. Ruit (Jos); J. Droogendijk (Jolanda); R.J. van Alphen (Robbert); T.D. den Boer (Tilly D.); M.H. Lam (Mei); A. Jager (Agnes); T. van Gelder (Teun); A.H.J. Mathijssen (Ron)

    2016-01-01

    textabstractBackground and Objective: The anti-oestrogen tamoxifen requires metabolic activation to endoxifen by cytochrome P450 (CYP) enzymes, predominantly CYP2D6. Potent CYP2D6-inhibiting antidepressants can seriously disrupt tamoxifen metabolism, probably influencing the efficacy of tamoxifen. F

  1. [Dopamine-dependent long-term depression in hippocampus of rat induced by exposure to spatial novelty.].

    Science.gov (United States)

    Liu, Na; Xue, Bin; Xing, Hua; Xu, Lin; Jiang, Shan-Xiang

    2009-12-25

    To study the role of long-term depression (LTD) in the mechanisms of learning and memory in hippocampus of rat, recordings were taken from freely moving animals that had undergone chronic implantation of a recording electrode in the hippocampus CA1 region and a bipolar stimulating electrode in the ipsilateral Schaffer collateral-commissural pathway. The recording electrode was inserted 3.8 mm posterior to bregma and 2.8 mm right of the midline, and the stimulating electrode was inserted 4.8 mm posterior to bregma and 3.8 mm right of the midline via holes drilled through the skull. The entire assembly was connected with a rubber socket on the animal's head and then stabilized with dental cement. The correct placement of the electrodes into the hippocampal CA1 area was confirmed via electrophysiological criteria and postmortem histological analysis. After 2 weeks of surgery recovery, the rats were placed in the familiar recording chamber for 3 days. The field excitatory postsynaptic potentials (fEPSPs) were evoked by stimulating with a square wave constant current pulse of 0.2 ms duration, at a frequency of 0.033 Hz and at a stimulation intensity adjusted to given an fEPSP amplitude of 50% of the maximum, and the baseline of fEPSPs were recorded for 3 days in the familiar recording environment at the same time each day. A novelty environment that was made of clear Perspex (40 cm x 40 cm x 40 cm) was prepared and we examined whether exposure to a novelty spatial environment facilitated the expression of activity-dependent persistent decrease in synaptic transmission (namely LTD) at CA1 synapses in the rat hippocampus. The results showed that brief exposure to a novelty environment for 10 min facilitated the expression of LTD in the hippocampal CA1 area under no other exogenous high- or low-frequency stimulation protocol. This facilitatory effect was dependent on the activation of D1/D5 receptors: the D1/D5 receptors antagonist SCH23390 prevented the decrease of

  2. Health effects following long-term exposure to thorium dusts. A fourteen-year follow-up study in China

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xingan; Cheng Younge; Zhen Rong [Ministry of Public Health, Beijing (China). Lab. of Industrial Hygiene

    2000-05-01

    A fourteen-year follow-up study was carried out at Baiyan Obo Rare-earth Iron Mine in China. It has been operating for forty one years. It's ore contains ThO2 at a percentage of 0.04. The purpose of this study is to investigate the possible health effects of 2903 dust-inhaled miners following long-term exposure to thorium dusts. An electrostatic collection system was used to measure the exhaled thoron activity of each examinee, through simple calculation, each examinee's thorium lung burden obtained. Health status was ascertained through questionnaire, physical examination and clinical laboratory tests. An epidemiological study on the mortality rates of lung cancers of the dust-inhaled miners and internal controls was also carried out. Results showed that the highest thorium lung burden for 1158 measurements of 638 miners was at a value of 11.11 Bq, one tenth of the maximum thorium lung burden. In a ten-year investigation on the four haematological parameters and four hepatic parameters of 638 exposed miners, no adverse effects were observed. The incidence of severe breathlessness, lung function tests, pneumoconiosis of stage O{sup +} and the concentration of ceruloplasmin in the serum of high thorium lung burden group are much higher than that of low thorium lung burden group. However, owing to the concentration of SiO2 (10%) are much higher than that of the ThO2 (0.04%) in the dust, the disorders of respiratory tract are mainly due to the fibrogenic effects of SiO2, Epidemiology study showed that both the SMRs of the dust-inhaled miners and the dust-free miners are all greater than one (5.15 vs. 2.30). The SMR of the dust miners was much higher than that of the controls. However, there was no statistic significant difference between these two SMRs (X{sup 2}=3.75 P>0.05). This means that the high SMR of the dust-inhaled miners was not solely due to the long-term inhaled thorium and short-lived thoron daughters. Because of very high percentage of smokers

  3. Effect of long-term (2 years) exposure of mouse brains to global system for mobile communication (GSM) radiofrequency fields on astrocytic immunoreactivity.

    Science.gov (United States)

    Court-Kowalski, Stefan; Finnie, John W; Manavis, Jim; Blumbergs, Peter C; Helps, Stephen C; Vink, Robert

    2015-04-01

    This study was designed to determine whether long-term (2 years) brain exposure to mobile telephone radiofrequency (RF) fields produces any astrocytic activation as these glia react to a wide range of neural perturbations by astrogliosis. Using a purpose-designed exposure system at 900 MHz, mice were given a single, far-field whole body exposure at a specific absorption rate of 4 W/kg on five successive days per week for 104 weeks. Control mice were sham-exposed or freely mobile in a cage to control any stress caused by immobilization in the exposure module. Brains were perfusion-fixed with 4% paraformaldehyde and three coronal levels immunostained for glial fibrillary acidic protein (GFAP). These brain slices were then examined by light microscopy and the amount of this immunomarker quantified using a color deconvolution method. There was no change in astrocytic GFAP immunostaining in brains after long-term exposure to mobile telephony microwaves compared to control (sham-exposed or freely moving caged mice). It was concluded that long-term (2 years) exposure of murine brains to mobile telephone RF fields did not produce any astrocytic reaction (astrogliosis) detectable by GFAP immunostaining.

  4. Effect of long-term exposure of 2.4 GHz radiofrequency radiation emitted from Wi-Fi equipment on testes functions.

    Science.gov (United States)

    Dasdag, Suleyman; Taş, Muzaffer; Akdag, Mehmet Zulkuf; Yegin, Korkut

    2015-03-01

    The aim of this study was to investigate long-term effects of radiofrequency radiation (RFR) emitted from a Wireless Fidelity (Wi-Fi) system on testes. The study was carried out on 16 Wistar Albino adult male rats by dividing them into two groups such as sham (n: 8) and exposure (n: 8). Rats in the exposure group were exposed to 2.4 GHz RFR radiation for 24 h/d during 12 months (1 year). The same procedure was applied to the rats in the sham control group except the Wi-Fi system was turned off. Immediately after the last exposure, rats were sacrificed and reproductive organs were removed. Motility (%), concentration (×10(6)/mL), tail defects (%), head defects (%) and total morphologic defects (%) of sperms and weight of testes (g), left epididymis (g), prostate (g), seminal vesicles (g) were determined. Seminiferous tubules diameter (μm) and tunica albuginea thickness (μm) were also measured. However, the results were evaluated by using Johnsen's score. Head defects increased in the exposure group (p  0.05). In conclusion, we observed that long-term exposure of 2.4 GHz RF emitted from Wi-Fi (2420 μW/kg, 1 g average) affects some of the reproductive parameters of male rats. We suggest Wi-Fi users to avoid long-term exposure of RF emissions from Wi-Fi equipment.

  5. Health Effects of Long-Term Exposure to Insecticide-Treated Mosquito Nets in the Control of Malaria in Endemic Regions, Revised

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2006-01-01

    Full Text Available The endemicity of malaria in tropical areas of the world persists, especially in countries south of Saharan Africa. The efforts and concerns invested by the World Health Organization and other health agencies to eradicate malaria are commendable. However, in spite of all these efforts, the loss in economic and human resources continues. In a previous report, the long-term health effects of insecticide-impregnated bednet (IIBN use were highlighted with the expectation of attracting serious thoughts and further research on the issue. This present paper is an update on that expectation. Results from a comprehensive literature search show that not much work has been done on the effects of long-term exposure to IIBNs in combating malarial infection. The efficacy of IIBNs is not in question. What is in question is whether long-term exposure to IIBNs have any health effects. The aims and outcomes of the research found in the literature on the subject to date seem to support only the efficacy of the temporal use of plain bednets, but not the use of IIBNs, and do not tell much about the long-term effects of IIBN exposure. All pesticides are toxic by nature and present risks of adverse effects. While there is agreement that IIBNs can be effective in reducing malarial morbidity and mortality under field trials, a number of factors relating to their long-term-exposure health effects have yet to be determined. Further reliable research projects are recommended urgently. However, some of the anticipated behavioral effects caused by insecticidal use will be avoided by the use of untreated nets instead.

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

    NARCIS (Netherlands)

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

    2015-01-01

    The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we

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

    NARCIS (Netherlands)

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

    2015-01-01

    The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we st

  8. Cryoprotectants are metabolic fuels during long term frost exposure in the earthworm Dendrobaena octaedra.

    DEFF Research Database (Denmark)

    C. Jørgensen, Sofia; Overgaard, Johannes; Holmstrup, Martin

    2008-01-01

    and glycogen levels indicating that depletion of fermentable resources was the primary cause of death. Calorimetric measurements of metabolic rate showed a 15-fold metabolic depression in frozen versus unfrozen worms and this reduction in metabolic rate is clearly of importance for long term survival of frozen...

  9. Effects of long-term acetyl-L-carnitine administration in rats: I. increased dopamine output in mesocorticolimbic areas and protection toward acute stress exposure.

    Science.gov (United States)

    Tolu, Pierluigi; Masi, Flavio; Leggio, Benedetta; Scheggi, Simona; Tagliamonte, Alessandro; De Montis, M Graziella; Gambarana, Carla

    2002-09-01

    Acetyl-L-carnitine (ALCAR) is the acetyl ester of carnitine that has been reported to be beneficial in depressive disorders and Alzheimer's disease. A 7-day administration of ALCAR in rats increased dopamine and serotonin output in the nucleus accumbens shell and it prevented the development of escape deficit produced by acute exposure to unavoidable stress. No tolerance developed to this protective effect, which appeared to be mediated by (1) the activation of 5-HT(1A) receptors, as it was antagonized by the administration of WAY100635 30 min before stress exposure; and (2) a process of neuronal plasticity dependent on NMDA receptor activity, as subcutaneous dizocilpine infusion during ALCAR treatment prevented the development of the protective effect on stress. Chronic stress exposure maintains an escape deficit condition that is reverted by a long-term treatment with antidepressants, but the same condition was not modified by long-term ALCAR administration. Thus, ALCAR cannot be defined as an antidepressant.

  10. Functional modifications of the enteric nervous system following radiation exposure: short and long term effects; Modifications du fonctionnement du systeme nerveux enterique suite a une exposition aux rayonnements ionisants: effets precoces et a long terme

    Energy Technology Data Exchange (ETDEWEB)

    Ropenga, A

    2003-09-15

    Exposure of the gastrointestinal tract to ionising radiation induces at short or at long term, digestive dysfunctions, including nausea, diarrhoea, constipation and eventually abdominal pain. The mechanisms implicated remain incompletely understood, but may involve at long term functional modifications of the enteric nervous system (ENS). The mediator 5-Hydroxytryptamine (5-HT, serotonin) is present in entero-chromaffin cells and the ENS and plays an important role in digestive functions. The aim of this work was to follow between 3 days and 3 months after an hemi-body irradiation (10 Gy, X rays) radiation-induced modifications of 5-HT content, 5-HT receptor expression and effects on electrolyte movement in rat distal colon. At 3 days following irradiation, a reduction of total epithelial cells was observed along with a diminution of 5-HT transporter expression. Receptors 5-HT{sub 1A} and 5-HT{sub 2A} expression was diminished concomitant with a reduced response to 5-HT or neural stimulation and an increased importance of the receptor 5-HT{sub 3}. At 7 days crypt total cell number was increased and the importance of receptors 5-HT{sub 2A} and 5-HT{sub 3} in the secretory response was also increased. At later times, between 28 and 43 days, irradiation increased mucosal 5-HT content. This increase can be related to an increase of the number of entero-chromaffin cells at 28 days and is concomitant with the diminution of the importance of the receptor 5-HT{sub 2A} in the secretory response. In conclusion, this project has established for the first time differential expression of 5-HT receptors in the mucosal and muscle layers in the distal colon. Moreover, irradiation induces modifications in 5-HT receptor expression and importance in secretory epithelial responses. Irradiation also disturbs the equilibrium of different cell types by the epithelium in increasing the number of entero-chromaffin cells containing 5-HT. (author)

  11. Molecular changes during neurodevelopment following second-trimester binge ethanol exposure in a mouse model of fetal alcohol spectrum disorder: from immediate effects to long-term adaptation.

    Science.gov (United States)

    Mantha, Katarzyna; Laufer, Benjamin I; Singh, Shiva M

    2014-01-01

    Fetal alcohol spectrum disorder (FASD) is an umbrella term that refers to a wide range of behavioral and cognitive deficits resulting from prenatal alcohol exposure. It involves changes in brain gene expression that underlie lifelong FASD symptoms. How these changes are achieved from immediate to long-term effects, and how they are maintained, is unknown. We have used the C57BL/6J mouse to assess the dynamics of genomic alterations following binge alcohol exposure. Ethanol-exposed fetal (short-term effect) and adult (long-term effect) brains were assessed for gene expression and microRNA (miRNA) changes using Affymetrix mouse arrays. We identified 48 and 68 differentially expressed genes in short- and long-term groups, respectively. No gene was common between the 2 groups. Short-term (immediate) genes were involved in cellular compromise and apoptosis, which represent ethanol's toxic effects. Long-term genes were involved in various cellular functions, including epigenetics. Using quantitative RT-PCR, we confirmed the downregulation of long-term genes: Camk1g, Ccdc6, Egr3, Hspa5, and Xbp1. miRNA arrays identified 20 differentially expressed miRNAs, one of which (miR-302c) was confirmed. miR-302c was involved in an inverse relationship with Ccdc6. A network-based model involving altered genes illustrates the importance of cellular redox, stress and inflammation in FASD. Our results also support a critical role of apoptosis in FASD, and the potential involvement of miRNAs in the adaptation of gene expression following prenatal ethanol exposure. The ultimate molecular footprint involves inflammatory disease, neurological disease and skeletal and muscular disorders as major alterations in FASD. At the cellular level, these processes represent abnormalities in redox, stress and inflammation, with potential underpinnings to anxiety.

  12. Accounting for differing exposure patterns between laboratory tests and the field in the assessment of long-term risks of pesticides to terrestrial vertebrates.

    Science.gov (United States)

    Fischer, David L

    2005-11-01

    Long-term risks of pesticides to birds and mammals are currently assessed by comparing effects thresholds determined in chronic laboratory studies to exposure levels expected to occur in the field. However, there is often a mismatch between exposure patterns tested in the laboratory tests (exposure levels held constant) and those experienced by animals in the field (exposure levels varying over time). Three methods for addressing this problem are presented and discussed. Time-weighted averaging (TWA) converts a variable field exposure regime to a single value that can be compared directly to the laboratory test results. Body-burden modeling (BBM) is applied to both laboratory and field exposure regimes allowing a straightforward comparison of body residue levels expected for each situation. Temporal analysis (TA) uses expert judgment to decide if the length of time exposure exceeds a toxicity threshold is long enough to cause biologically significant effects. To reduce uncertainty in long-term assessments, the conduct of specialized laboratory tests in which test subjects are administered a time-varying exposure that mimics what occurs in the field should be considered. Such tests may also be useful testing the validity of each of these assessment methods.

  13. Effects of long-term radiation exposure on the higher aquatic plants in the Chernobyl exclusion zone

    Energy Technology Data Exchange (ETDEWEB)

    Shevtsova, N.; Gudkov, D. [Institute of Hydrobiology (Russian Federation)

    2014-07-01

    germinated seeds) and pinnacle deviations was registered in plants from the most radioactive contaminated water bodies. Also the decreasing of parasitic stability of one of aquatic plant communities' dominant species - the common reed is observed. The data of the mite Steneotarsonemus phragmitidis and the parasitic fungus Claviceps purpurea hitting of the common reed, correlated with radiation dose rate. It was determined the positive correlation between absorbed dose rate and chromosome aberration rate in roots of the twelve aquatic plants' species from sampling water bodies. The highest rate of chromosome aberrations (up to 17 %) were registered in plants with high level of morphological deviations in seeds germs, but not panicles. The data obtained from the complex analysis of natural aquatic plant communities from the radioactive contaminated water bodies testify about rather high level of genetic efficiency of low doses of long-term exposure. For higher aquatic plants from ChEZ there is observed a realization of radiobiological reactions on morphological and reproductive levels on the background of genetic instability induced by low doses. Document available in abstract form only. (authors)

  14. Long-term exposure of A549 cells to titanium dioxide nanoparticles induces DNA damage and sensitizes cells towards genotoxic agents.

    Science.gov (United States)

    Armand, Lucie; Tarantini, Adeline; Beal, David; Biola-Clier, Mathilde; Bobyk, Laure; Sorieul, Sephanie; Pernet-Gallay, Karin; Marie-Desvergne, Caroline; Lynch, Iseult; Herlin-Boime, Nathalie; Carriere, Marie

    2016-09-01

    Titanium dioxide nanoparticles (TiO2-NPs) are one of the most produced NPs in the world. Their toxicity has been studied for a decade using acute exposure scenarios, i.e. high exposure concentrations and short exposure times. In the present study, we evaluated their genotoxic impact using long-term and low concentration exposure conditions. A549 alveolar epithelial cells were continuously exposed to 1-50 μg/mL TiO2-NPs, 86% anatase/14% rutile, 24 ± 6 nm average primary diameter, for up to two months. Their cytotoxicity, oxidative potential and intracellular accumulation were evaluated using MTT assay and reactive oxygen species measurement, transmission electron microscopy observation, micro-particle-induced X-ray emission and inductively-coupled plasma mass spectroscopy. Genotoxic impact was assessed using alkaline and Fpg-modified comet assay, immunostaining of 53BP1 foci and the cytokinesis-blocked micronucleus assay. Finally, we evaluated the impact of a subsequent exposure of these cells to the alkylating agent methyl methanesulfonate. We demonstrate that long-term exposure to TiO2-NPs does not affect cell viability but causes DNA damage, particularly oxidative damage to DNA and increased 53BP1 foci counts, correlated with increased intracellular accumulation of NPs. In addition, exposure over 2 months causes cellular responses suggestive of adaptation, characterized by decreased proliferation rate and stabilization of TiO2-NP intracellular accumulation, as well as sensitization to MMS. Taken together, these data underline the genotoxic impact and sensitization effect of long-term exposure of lung alveolar epithelial cells to low levels of TiO2-NPs.

  15. Application of {sup 1}H-NMR-based metabolomics for detecting injury induced by long-term microwave exposure in Wistar rats' urine

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-Feng; Peng, Rui-Yun; Wang, Shui-Ming; Gao, Ya-Bing; Dong, Ji; Zhao, Li; Li, Xiang; Zuo, Hong-Yan; Wang, Chang-Zhen [Beijing Institute of Radiation Medicine, Laboratory of Pathology, Beijing (China); Hu, Xiang-Jun [Beijing Institute of Radiation Medicine, Beijing (China); Gao, Rong-Lian [Beijing Institute of Radiation Medicine, Laser Medicine, Beijing (China); Su, Zhen-Tao [Beijing Institute of Radiation Medicine, Radiation Protection, Beijing (China); Feng, Xin-Xing [Chinese Academy of Medical Sciences, Endocrine and Cardiovascular Center, Fuwai Hospital and Cardiovascular Institute, Beijing (China)

    2012-07-15

    There has been growing public concern regarding exposure to microwave fields as a potential human health hazard. This study aimed to identify sensitive biochemical indexes for the detection of injury induced by microwave exposure. Male Wistar rats were exposed to microwaves for 6 min per day, 5 days per week over a period of 1 month at an average power density of 5 mW/cm{sup 2} (specific absorption rate of 2.1 W/kg). Urine specimens were collected over 24 h in metabolic cages at 7 days, 21 days, 2 months, and 6 months after exposure. {sup 1}H NMR spectroscopy data were analyzed using multivariate statistical techniques. Urine metabolic profiles of rats after long-term microwave exposure were significantly differentiated from those of sham-treated controls using principal component analysis or partial least squares discriminant analysis. Significant differences in low molecular weight metabolites (acetate, succinate, citrate, ketoglutarate, glucose, taurine, phenylalanine, tyrosine, and hippurate) were identified in the 5 mW/cm{sup 2} microwave exposure group compared with the sham-treated controls at 7 days, 21 days, and 2 months. Metabolites returned to normal levels by 6 months after exposure. These data indicated that these metabolites were related to the perturbations of energy metabolism particularly in the tricarboxylic acid cycle, and the metabolism of amino acids, monoamines, and choline in urine represent potential indexes for the detection of injury induced by long-term microwave exposure. (orig.)

  16. Tip-of-the-tongue in a second language: the effects of brief first-language exposure and long-term use.

    Science.gov (United States)

    Kreiner, Hamutal; Degani, Tamar

    2015-04-01

    Bilinguals have more tip-of-the-tongue (TOT) incidents than monolinguals. Whereas previous research has focused on differences in the long term language experience between these groups, the present study examined the hypothesis that both long-term and transient context factors modulate TOT rates. Russian-Hebrew bilinguals who acquired Hebrew either early (11years) were compared to native Hebrew speakers on a picture naming task in Hebrew, before and after viewing a short movie in Russian. Both the short-term context (before-after the movie) and long-term language experience modulated TOT rates: Late bilinguals exhibited significantly higher TOT rates than early bilinguals who did not significantly differ from native Hebrew speakers. Critically, following the Russian movie, bilinguals in both groups differed from the native speakers of the target language. Thus, exposure to the non-target language exerted a global, non-item-specific, cross-language interference effect. The findings highlight the dynamic nature of the bilingual system in which both short and long-term language experience operate to influence bilingual performance.

  17. Effects of six priority controlled phthalate esters with long-term low-dose integrated exposure on male reproductive toxicity in rats.

    Science.gov (United States)

    Gao, Hai-Tao; Xu, Run; Cao, Wei-Xin; Qian, Liang-Liang; Wang, Min; Lu, Lingeng; Xu, Qian; Yu, Shu-Qin

    2017-03-01

    Human beings are inevitably exposed to ubiquitous phthalate esters (PEs) surroundings. The purposes of this study were to investigate the effects of long-term low-dose exposure to the mixture of six priority controlled phthalate esters (MIXPs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethyhexyl) phthalate (DEHP) and di-n-octyl phthalate (DNOP), on male rat reproductive system and further to explore the underlying mechanisms of the reproductive toxicity. The male rats were orally exposed to either sodium carboxymethyl cellulose as controls or MIXPs at three different low-doses by gavage for 15 weeks. Testosterone and luteinizing hormone (LH) in serum were analyzed, and pathological examinations were performed for toxicity evaluation. Steroidogenic proteins (StAR, P450scc, CYP17A1 and 17β-HSD), cell cycle and apoptosis-related proteins (p53, Chk1, Cdc2, CDK6, Bcl-2 and Bax) were measured for mechanisms exploration. MIXPs with long-term low-dose exposure could cause male reproductive toxicity to the rats, including the decrease of both serum and testicular testosterone, and the constructional damage of testis. These effects were related to down-regulated steroidogenic proteins, arresting cell cycle progression and promoting apoptosis in rat testicular cells. The results indicate that MIXPs with long-term low-dose exposure may pose male reproductive toxicity in human. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Risk of death from cardiovascular disease associated with low-level arsenic exposure among long-term smokers in a US population-based study

    Science.gov (United States)

    Farzan, Shohreh F.; Chen, Yu; Rees, Judy R.; Zens, M. Scot; Karagas, Margaret R.

    2015-01-01

    High levels of arsenic exposure have been associated with increases in cardiovascular disease risk. However, studies of arsenic’s effects at lower exposure levels are limited and few prospective studies exist in the United States using long-term arsenic exposure biomarkers. We conducted a prospective analysis of the association between toenail arsenic and cardiovascular disease mortality using longitudinal data collected on 3939 participants in the New Hampshire Skin Cancer Study. Using Cox proportional hazard models adjusted for potential confounders, we estimated hazard ratios and 95% confidence intervals associated with the risk of death from any cardiovascular disease, ischemic heart disease, and stroke, in relation to natural-log transformed toenail arsenic concentrations. In this US population, although we observed no overall association, arsenic exposure measured from toenail clipping samples was related to an increased risk of ischemic heart disease mortality among long-term smokers (as reported at baseline), with increased hazard ratios among individuals with ≥ 31 total smoking years (HR: 1.52, 95% CI: 1.02, 2.27), ≥ 30 pack-years (HR: 1.66, 95% CI: 1.12, 2.45), and among current smokers (HR: 1.69, 95% CI: 1.04, 2.75). These results are consistent with evidence from more highly exposed populations suggesting a synergistic relationship between arsenic exposure and smoking on health outcomes and support a role for lower-level arsenic exposure in ischemic heart disease mortality. PMID:26048586

  19. Long-term, passive exposure to non-traumatic acoustic noise induces neural adaptation in the adult rat medial geniculate body and auditory cortex.

    Science.gov (United States)

    Lau, Condon; Zhang, Jevin W; McPherson, Bradley; Pienkowski, Martin; Wu, Ed X

    2015-02-15

    Exposure to loud sounds can lead to permanent hearing loss, i.e., the elevation of hearing thresholds. Exposure at more moderate sound pressure levels (SPLs) (non-traumatic and within occupational limits) may not elevate thresholds, but could in the long-term be detrimental to speech intelligibility by altering its spectrotemporal representation in the central auditory system. In support of this, electrophysiological and behavioral changes following long-term, passive (no conditioned learning) exposure at moderate SPLs have recently been observed in adult animals. To assess the potential effects of moderately loud noise on the entire auditory brain, we employed functional magnetic resonance imaging (fMRI) to study noise-exposed adult rats. We find that passive, pulsed broadband noise exposure for two months at 65 dB SPL leads to a decrease of the sound-evoked blood oxygenation level-dependent fMRI signal in the thalamic medial geniculate body (MGB) and in the auditory cortex (AC). This points to the thalamo-cortex as the site of the neural adaptation to the moderately noisy environment. The signal reduction is statistically significant during 10 Hz pulsed acoustic stimulation (MGB: pnoise exposure has a greater effect on the processing of higher pulse rate sounds. This study has enhanced our understanding of functional changes following exposure by mapping changes across the entire auditory brain. These findings have important implications for speech processing, which depends on accurate processing of sounds with a wide spectrum of pulse rates.

  20. Long-term electromagnetic pulse exposure induces Abeta deposition and cognitive dysfunction through oxidative stress and overexpression of APP and BACE1.

    Science.gov (United States)

    Jiang, Da-Peng; Li, Jin-Hui; Zhang, Jie; Xu, Sheng-Long; Kuang, Fang; Lang, Hai-Yang; Wang, Ya-Feng; An, Guang-Zhou; Li, Jing; Guo, Guo-Zhen

    2016-07-01

    A progressively expanded literature has been devoted in the past years to the noxious or beneficial effects of electromagnetic field (EMF) to Alzheimer׳s disease (AD). This study concerns the relationship between electromagnetic pulse (EMP) exposure and the occurrence of AD in rats and the underlying mechanisms, focusing on the role of oxidative stress (OS). 55 healthy male Sprague Dawley (SD) rats were used and received continuous exposure for 8 months. Morris water maze (MWM) test was conducted to test the ability of cognitive and memory. The level of OS was detected by superoxide dismutase (SOD) activity and glutathione (GSH) content. We found that long-term EMP exposure induced cognitive damage in rats. The content of β-amyloid (Aβ) protein in hippocampus was increased after long-term EMP exposure. OS of hippocampal neuron was detected. Western blotting and immunohistochemistry (IHC) assay showed that the content of Aβ protein and its oligomers in EMP-exposed rats were higher than that of sham-exposed rats. The content of Beta Site App Cleaving Enzyme (BACE1) and microtubule-associated protein 1 light chain 3-II (LC3-II) in EMP-exposed rats hippocampus were also higher than that of sham-exposed rats. SOD activity and GSH content in EMP-exposed rats were lower than sham-exposed rats (pEMP exposure-induced OS, including increased amyloid precursor protein (APP) aberrant cleavage. Although further study is needed, the present results suggest that long-term EMP exposure is harmful to cognitive ability in rats and could induce AD-like pathological manifestation.

  1. Long-term exposure to cigarette smoke extract induces hypomethylation at the RUNX3 and IGF2-H19 loci in immortalized human urothelial cells.

    Directory of Open Access Journals (Sweden)

    Li-Mei Chen

    Full Text Available Cigarette smoking is the single most important epidemiological risk factor for bladder cancer but it is not known whether exposure of urothelial cells to the systemic soluble contents of cigarette smoke is directly causative to bladder cancer and the associated epigenetic changes such as tumor suppressor gene hypermethylation. We undertook this study to investigate if long-term treatment of human urothelial cells with cigarette smoke extract (CSE results in tumor suppressor gene hypermethylation, a phenotype that was previously associated with long-term constant CSE treatment of airway epithelial cells. We chronically treated an immortalized human urothelial cell line UROtsa with CSE using a cyclic daily regimen but the cells were cultured in CSE-free medium between daily treatments. Bisulfite sequencing and real-time PCR array-based methylation profiling were employed to evaluate methylation changes at tumor suppressor gene loci in the chronically CSE-treated cells versus the passage-matched untreated control cells. The RUNX3 tumor suppressor gene promoter was hypomethylated with a significant increase in proportion of the completely unmethylated haplotype after the long-term CSE treatment; whereas RUNX3 promoter hypermethylation was previously reported for bladder cancers of smokers. Hypomethylation induced by the long-term CSE treatment was also observed for the IGF2-H19 locus. The methylation status at the PRSS8/prostasin and 16 additional loci however, was unaffected by the chronic CSE treatment. Transient CSE treatment over 1 daily regimen resulted in transcriptional down-regulation of RUNX3 and H19, but only the H19 transcription was down-regulated in the chronically CSE-treated urothelial cells. Transcription of a key enzyme in one-carbon metabolism, dihydrofolate reductase (DHFR was greatly reduced by the long-term CSE treatment, potentially serving as a mechanism for the hypomethylation phenotype via a reduced supply of methyl donor

  2. Lessons Learned Through the Follow-up of the Long-Term Effects of Over-Exposure to an Ir192 Industrial Radiography Source in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Jalil, A.; Rabbani, G.; Hossain, M. K.; Alam, M. K.; Koddus, A.

    2003-02-24

    An industrial radiographer was accidentally over-exposed while taking the radiograph of weld-joints of gas pipe-lines in 1985 in Bangladesh. Symptoms of high radiation exposure occurred immediately after the accident and skin erythema developed leading to progressive tissue deterioration. The consequences of this over-exposure is being followed up to assess the long-term effects of ionizing radiation on the victim. Progressive tissue deteriorations have already led to multiple surgeries and successive amputations of the finger-tips so far. Lessons learned from this accident are also reported in this paper.

  3. Cytophysiological Changes in the Follicular Epithelium of the Thyroid Gland after Long-Term Exposure to Low Doses of Dichlorodiphenyltrichloroethane (DDT).

    Science.gov (United States)

    Yaglova, N V; Yaglov, V V

    2017-03-01

    Exposure to endocrine disruptors is considered as a risk factor thyroid gland diseases. We analyzed cytophysiological changes in rat thyroid follicular epithelium after long-term exposure to low doses of the most widespread disruptor DDT. Analysis of thyroid hormone production and light and electron microscopy of thyroid gland samples revealed cytophysiological changes in thyroid epithelium related to impaired transport through the apical membrane, suppressed Golgi complex activity, and impaired thyrotrophic hormone regulation of the secretory functions of thyroid cells, which led to compensatory transition from merocrine to microapocrine secret release.

  4. Dextromethorphan as a phenotyping test to predict endoxifen exposure in patients on tamoxifen treatment

    NARCIS (Netherlands)

    Graan, A.J. de; Teunissen, S.F.; Vos, F.Y. de; Loos, W.J.; Schaik, R.H. van; Jongh, F.E. de; Vos, A.I. de; Alphen, R.J. van; Holt, B. van der; Verweij, J.; Seynaeve, C.; Beijnen, J.H.; Mathijssen, R.H.

    2011-01-01

    PURPOSE: Tamoxifen, a widely used agent for the prevention and treatment of breast cancer, is mainly metabolized by CYP2D6 and CYP3A to form its most abundant active metabolite, endoxifen. Interpatient variability in toxicity and efficacy of tamoxifen is substantial. Contradictory results on the val

  5. Dextromethorphan as a phenotyping test to predict endoxifen exposure in patients on tamoxifen treatment

    NARCIS (Netherlands)

    Graan, A.J. de; Teunissen, S.F.; Vos, F.Y. de; Loos, W.J.; Schaik, R.H. van; Jongh, F.E. de; Vos, A.I. de; Alphen, R.J. van; Holt, B. van der; Verweij, J.; Seynaeve, C.; Beijnen, J.H.; Mathijssen, R.H.

    2011-01-01

    PURPOSE: Tamoxifen, a widely used agent for the prevention and treatment of breast cancer, is mainly metabolized by CYP2D6 and CYP3A to form its most abundant active metabolite, endoxifen. Interpatient variability in toxicity and efficacy of tamoxifen is substantial. Contradictory results on the val

  6. Approaches for predicting effects of unintended environmental exposure to an endocrine active pharmaceutical, tamoxifen

    Science.gov (United States)

    Tamoxifen is an endocrine-active pharmaceutical (EAP) that is used world-wide. Because tamoxifen is a ubiquitous pharmaceutical and interacts with estrogen receptors, a case study was conducted with this compound to (1) determine effects on reproductive endpoints in a nontarget s...

  7. Approaches for predicting effects of unintended environmental exposure to an endocrine active pharmaceutical, tamoxifen

    Science.gov (United States)

    Tamoxifen is an endocrine-active pharmaceutical (EAP) that is used world-wide. Because tamoxifen is a ubiquitous pharmaceutical and interacts with estrogen receptors, a case study was conducted with this compound to (1) determine effects on reproductive endpoints in a nontarget s...

  8. NLRP3 inflammasome activation by mitochondrial reactive oxygen species plays a key role in long-term cognitive impairment induced by paraquat exposure.

    Science.gov (United States)

    Chen, Liuji; Na, Ren; Boldt, Erin; Ran, Qitao

    2015-09-01

    Exposure to environmental toxins such as pesticides is implicated in increasing Alzheimer's disease risk. In this study, we investigated the long-term effects of paraquat exposure on cognition of Alzheimer's disease animal model APP/PS1 mice and wild-type (WT) mice. Our results showed that APP/PS1 mice had exacerbated cognition impairment and elevated Aβ levels at 5 months after paraquat exposure, and that WT mice had cognition impairment at 5 and 16 months after paraquat exposure. In addition, increased mitochondrial oxidative stress and augmented brain inflammation were observed in both paraquat-exposed APP/PS1 mice and WT mice. Interestingly, activation of NLRP3 inflammasome, which triggers inflammation in response to mitochondrial stress, was enhanced in paraquat-exposed mice. Moreover, transgenic mice overexpressing Prdx3, a key enzyme in detoxifying mitochondrial H2O2, had suppressed NLRP3 inflammasome activation, reduced brain inflammation, and attenuated cognition impairment after paraquat exposure. Together, our results indicate that NLRP3 inflammasome activation induced by mitochondrial reactive oxygen species plays a key role in mediating paraquat-induced long-term cognition decline by elevating brain inflammation.

  9. Long-term exposure to antibiotics has caused accumulation of resistance determinants in the gut microbiota of honeybees.

    Science.gov (United States)

    Tian, Baoyu; Fadhil, Nibal H; Powell, J Elijah; Kwong, Waldan K; Moran, Nancy A

    2012-10-30

    Antibiotic treatment can impact nontarget microbes, enriching the pool of resistance genes available to pathogens and altering community profiles of microbes beneficial to hosts. The gut microbiota of adult honeybees, a distinctive community dominated by eight bacterial species, provides an opportunity to examine evolutionary responses to long-term treatment with a single antibiotic. For decades, American beekeepers have routinely treated colonies with oxytetracycline for control of larval pathogens. Using a functional metagenomic screen of bacteria from Maryland bees, we detected a high incidence of tetracycline/oxytetracycline resistance. This resistance is attributable to known resistance loci for which nucleotide sequences and flanking mobility genes were nearly identical to those from human pathogens and from bacteria associated with farm animals. Surveys using diagnostic PCR and sequencing revealed that gut bacteria of honeybees from diverse localities in the United States harbor eight tetracycline resistance loci, including efflux pump genes (tetB, tetC, tetD, tetH, tetL, and tetY) and ribosome protection genes (tetM and tetW), often at high frequencies. Isolates of gut bacteria from Connecticut bees display high levels of tetracycline resistance. Resistance genes were ubiquitous in American samples, though rare in colonies unexposed for 25 years. In contrast, only three resistance loci, at low frequencies, occurred in samples from countries not using antibiotics in beekeeping and samples from wild bumblebees. Thus, long-term antibiotic treatment has caused the bee gut microbiota to accumulate resistance genes, drawn from a widespread pool of highly mobile loci characterized from pathogens and agricultural sites. We found that 50 years of using antibiotics in beekeeping in the United States has resulted in extensive tetracycline resistance in the gut microbiota. These bacteria, which form a distinctive community present in healthy honeybees worldwide, may

  10. 78 FR 7860 - Initial Research on the Long-Term Health Consequences of Exposure to Burn Pits in Iraq and...

    Science.gov (United States)

    2013-02-04

    ... between exposure to combustion products and reduced pulmonary function, but inadequate or insufficient evidence of an association between exposure to combustion products and cancer, respiratory diseases... pulmonary function in the populations studied. Pulmonary function tests are frequently used to...

  11. Long-term Exposure to PM10 and NO2 in Association with Lung Volume and Airway Resistance in the MAAS Birth Cohort

    Science.gov (United States)

    Agius, Raymond M.; de Vocht, Frank; Lindley, Sarah; Gerrard, William; Lowe, Lesley; Belgrave, Danielle; Custovic, Adnan; Simpson, Angela

    2013-01-01

    Background: Findings from previous studies on the effects of air pollution exposure on lung function during childhood have been inconsistent. A common limitation has been the quality of exposure data used, and few studies have modeled exposure longitudinally throughout early life. Objectives: We sought to study the long-term effects of exposure to particulate matter with an aerodynamic diameter ≤ 10 μm (PM10) and to nitrogen dioxide (NO2) on specific airway resistance (sRaw) and forced expiratory volume in 1 sec (FEV1) before and after bronchodilator treatment. Subjects were from the Manchester Asthma and Allergy Study (MAAS) birth cohort (n = 1,185). Methods: Spirometry was performed during clinic visits at ages 3, 5, 8, and 11 years. Individual-level PM10 and NO2 exposures were estimated from birth to 11 years of age through a microenvironmental exposure model. Longitudinal and cross-sectional associations were estimated using generalized estimating equations and multivariable linear regression models. Results: Lifetime exposure to PM10 and NO2 was associated with significantly less growth in FEV1 (percent predicted) over time, both before (–1.37%; 95% CI: –2.52, –0.23 for a 1-unit increase in PM10 and –0.83%; 95% CI: –1.39, –0.28 for a 1-unit increase in NO2) and after bronchodilator treatment (–3.59%; 95% CI: –5.36, –1.83 and –1.20%; 95% CI: –1.97, –0.43, respectively). We found no association between lifetime exposure and sRaw over time. Cross-sectional analyses of detailed exposure estimates for the summer and winter before 11 years of age and lung function at 11 years indicated no significant associations. Conclusions: Long-term PM10 and NO2 exposures were associated with small but statistically significant reductions in lung volume growth in children of elementary-school age. Citation: Mölter A, Agius RM, de Vocht F, Lindley S, Gerrard W, Lowe L, Belgrave D, Custovic A, Simpson A. 2013. Long-term exposure to PM10 and NO2 in

  12. Properties of pure nickel after long term exposures to LiOH and vacuum at 775 K

    Science.gov (United States)

    Whittenberger, J. D.

    1991-01-01

    The solid to liquid phase transformation of LiOH at 744.3 K is considered to be an ideal candidate thermal energy storage (TES) mechanism for a Rankine heat engine based solar dynamic system operating at approximately 682 K. While pure nickel is thought to be a suitable containment material for LiOH, long term containment is of concern because molten hydroxides are usually corrosive. Two commercially pure nickel alloys, Ni-200 and Ni-201, were exposed to molten LiOH, its vapor, and vacuum at 775 K for periods ranging from 50 to 5000 h, and simple mechanical property measurements (77 to 900 K tensile and 750 K creep rupture) of exposed alloys were undertaken. The mechanical property test procedures are described and tabular lists of the test data are presented.

  13. Risk of death from cardiovascular disease associated with low-level arsenic exposure among long-term smokers in a US population-based study

    Energy Technology Data Exchange (ETDEWEB)

    Farzan, Shohreh F. [Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH (United States); Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY (United States); Chen, Yu [Departments of Population Health and Environmental Medicine, New York University School of Medicine, New York, NY (United States); Rees, Judy R.; Zens, M. Scot [Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH (United States); Karagas, Margaret R., E-mail: margaret.r.karagas@dartmouth.edu [Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH (United States)

    2015-09-01

    High levels of arsenic exposure have been associated with increases in cardiovascular disease risk. However, studies of arsenic's effects at lower exposure levels are limited and few prospective studies exist in the United States using long-term arsenic exposure biomarkers. We conducted a prospective analysis of the association between toenail arsenic and cardiovascular disease mortality using longitudinal data collected on 3939 participants in the New Hampshire Skin Cancer Study. Using Cox proportional hazard models adjusted for potential confounders, we estimated hazard ratios and 95% confidence intervals associated with the risk of death from any cardiovascular disease, ischemic heart disease, and stroke, in relation to natural-log transformed toenail arsenic concentrations. In this US population, although we observed no overall association, arsenic exposure measured from toenail clipping samples was related to an increased risk of ischemic heart disease mortality among long-term smokers (as reported at baseline), with increased hazard ratios among individuals with ≥ 31 total smoking years (HR: 1.52, 95% CI: 1.02, 2.27), ≥ 30 pack-years (HR: 1.66, 95% CI: 1.12, 2.45), and among current smokers (HR: 1.69, 95% CI: 1.04, 2.75). These results are consistent with evidence from more highly exposed populations suggesting a synergistic relationship between arsenic exposure and smoking on health outcomes and support a role for lower-level arsenic exposure in ischemic heart disease mortality. - Highlights: • Arsenic (As) has been associated with increased cardiovascular disease (CVD) risk. • Little is known about CVD effects at lower levels of As exposure common in the US. • Few have investigated the joint effects of As and smoking on CVD in US adults. • We examine chronic low-level As exposure and smoking in relation to CVD mortality. • Arsenic exposure may increase ischemic heart disease mortality among smokers in US.

  14. Association between children's forced vital capacity and long-term exposure to local ambient temperature in China: A national cross-sectional survey.

    Science.gov (United States)

    Li, Qin; Wang, Hai-Jun; Song, Yi; Ma, Jun; Song, Jie-Yun; Guo, Yuming

    2016-07-01

    It is well documented that short-term exposure to extreme ambient temperature is associated with respiratory disorder. However, few studies have assessed the long-term effect of temperature on children's lung function. The present study aimed to investigate the association between long-term exposure to local ambient temperature and children's forced vital capacity (FVC) in China. We analyzed the FVC data of 71,768 children from the 2010 Chinese National Survey on Students' Construction and Health (CHNSCH), and local annual average ambient temperature, relative humidity, air pollutants data from China Meteorological Administration and Ministry of Environment Protection of China. Generalized additive model (GAM) with non-linear function was used to examine the effect of ambient temperature on children's FVC. The results showed that low temperature was significantly associated with decrease of FVC in Chinese children within certain temperature range while adjusting for individual characteristics, socioeconomic conditions, air pollutants and relative humidity. The largest alteration of FVC related to the annual average temperature difference among cities from 20.4°C to 4.5°C was observed, being 242.7ml (95%CI: 220.0, 265.3) decrease in FVC. The similar association was found in both physically active and inactive children, while the largest alteration of FVC related to the temperature difference reached 329.1ml (95%CI: 296.7, 361.6) in physically active children and 290.5ml (95%CI: 255.7, 325.3) in physically inactive ones. Public health policy should be developed for protecting children's respiratory health during growth and development in some areas with cold weather. Key message What is the key question? Few studies have assessed the long-term effect of temperature on children's forced vital capacity (FVC). We analyzed the Chinese national survey data to clarify the association between children's forced vital capacity and long-term exposure to local ambient

  15. Time trends in cancer risk and pesticide exposure, a long-term follow-up of Danish gardeners

    DEFF Research Database (Denmark)

    Hansen, Eva Støttrup; Lander, Flemming; Lauritsen, Jens

    2007-01-01

    Occupational exposure to petrochemical pesticides was high during the first 10-15 years after their introduction in the late 1940s, and, during these years, many cases of intoxication occurred. In the 1960s, the use and marketing of pesticides was regulated to reduce exposure to these substances...

  16. Prior Exposure to Interpersonal Violence and Long-term Treatment Response for Boys with a Disruptive Behavior Disorder

    Science.gov (United States)

    Shenk, Chad E.; Dorn, Lorah D.; Kolko, David J.; Rausch, Joseph R.; Insana, Salvatore P.

    2016-01-01

    Interpersonal violence (IPV) is common in children with a disruptive behavior disorder (DBD) and increases the risk for greater DBD symptom severity, callous-unemotional (CU) traits, and neuroendocrine disruption. Thus, IPV may make it difficult to change symptom trajectories for families receiving DBD interventions given these relationships. The current study examined whether IPV prior to receiving treatment for a DBD predicted trajectories of a variety of associated outcomes, specifically DBD symptoms, CU traits, and cortisol concentrations. Boys with a DBD diagnosis (N = 66; age range = 6-11 years; 54.5% of whom experienced IPV prior to treatment) of either oppositional defiant disorder or conduct disorder participated in a randomized clinical trial and were assessed 3 years following treatment. Multilevel modeling demonstrated that prior IPV predicted smaller rates of change in DBD symptoms, CU traits, and cortisol trajectories, indicating less benefit from intervention. The effect size magnitudes of IPV were large for each outcome (d = 0.88 – 1.07). These results suggest that IPV is a predictor of the long-term treatment response for boys with a DBD. Including trauma-focused components into existing DBD interventions may be worth testing to improve treatment effectiveness for boys with a prior history of IPV. PMID:25270151

  17. Modelling of long-term behaviour of caesium and strontium radionuclides in the Arctic environment and human exposure

    Energy Technology Data Exchange (ETDEWEB)

    Golikov, Vladislav E-mail: bazil@sg5816.spb.edu; Logacheva, Irina; Bruk, Gennadi; Shutov, Vladimir; Balonov, Mikhail; Strand, Per; Borghuis, Sander; Howard, Brenda; Wright, Simon

    2004-07-01

    In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain 'lichen-reindeer-man' is outlined. Based upon an analysis of measured {sup 137}Cs and {sup 90}Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the 'lichen-reindeer-man' food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both {sup 137}Cs and {sup 90}Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m{sup -2} of {sup 137}Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions.

  18. Modelling of long-term behaviour of caesium and strontium radionuclides in the Arctic environment and human exposure.

    Science.gov (United States)

    Golikov, Vladislav; Logacheva, Irina; Bruk, Gennadi; Shutov, Vladimir; Balonov, Mikhail; Strand, Per; Borghuis, Sander; Howard, Brenda; Wright, Simon

    2004-01-01

    In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain "lichen-reindeer-man" is outlined. Based upon an analysis of measured (137)Cs and (90)Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the "lichen-reindeer-man" food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both (137)Cs and (90)Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m(-2) of (137)Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions.

  19. The impact of long-term hydrocarbon exposure on the structure, activity, and biogeochemical functioning of microbial mats.

    Science.gov (United States)

    Aubé, Johanne; Senin, Pavel; Pringault, Olivier; Bonin, Patricia; Deflandre, Bruno; Bouchez, Olivier; Bru, Noëlle; Biritxinaga-Etchart, Edurne; Klopp, Christophe; Guyoneaud, Rémy; Goñi-Urriza, Marisol

    2016-10-15

    Photosynthetic microbial mats are metabolically structured systems driven by solar light. They are ubiquitous and can grow in hydrocarbon-polluted sites. Our aim is to determine the impact of chronic hydrocarbon contamination on the structure, activity, and functioning of a microbial mat. We compared it to an uncontaminated mat harboring similar geochemical characteristics. The mats were sampled in spring and fall for 2years. Seasonal variations were observed for the reference mat: sulfur cycle-related bacteria dominated spring samples, while Cyanobacteria dominated in autumn. The contaminated mat showed minor seasonal variation; a progressive increase of Cyanobacteria was noticed, indicating a perturbation of the classical seasonal behavior. Hydrocarbon content was the main factor explaining the differences in the microbial community structure; however, hydrocarbonoclastic bacteria were among rare or transient Operational Taxonomic Units (OTUs) in the contaminated mat. We suggest that in long-term contaminated systems, hydrocarbonoclastic bacteria cannot be considered a sentinel of contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Altered carbon turnover processes and microbiomes in soils under long-term extremely high CO2 exposure.

    Science.gov (United States)

    Beulig, Felix; Urich, Tim; Nowak, Martin; Trumbore, Susan E; Gleixner, Gerd; Gilfillan, Gregor D; Fjelland, Kristine E; Küsel, Kirsten

    2016-01-01

    There is only limited understanding of the impact of high p(CO2) on soil biomes. We have studied a floodplain wetland where long-term emanations of temperate volcanic CO2 (mofettes) are associated with accumulation of carbon from the Earth's mantle. With an integrated approach using isotope geochemistry, soil activity measurements and multi-omics analyses, we demonstrate that high (nearly pure) CO2 concentrations have strongly affected pathways of carbon production and decomposition and therefore carbon turnover. In particular, a promotion of dark CO2 fixation significantly increased the input of geogenic carbon in the mofette when compared to a reference wetland soil exposed to normal levels of CO2. Radiocarbon analysis revealed that high quantities of mofette soil carbon originated from the assimilation of geogenic CO2 (up to 67%) via plant primary production and subsurface CO2 fixation. However, the preservation and accumulation of almost undegraded organic material appeared to be facilitated by the permanent exclusion of meso- to macroscopic eukaryotes and associated physical and/or ecological traits rather than an impaired biochemical potential for soil organic matter decomposition. Our study shows how CO2-induced changes in diversity and functions of the soil community can foster an unusual biogeochemical profile.

  1. Reactive Oxygen Species-mediated Loss of Phenotype of Parvalbumin Interneurons Contributes to Long-term Cognitive Impairments After Repeated Neonatal Ketamine Exposures.

    Science.gov (United States)

    Zhang, Hui; Sun, Xiao-Ru; Wang, Jing; Zhang, Zhen-Zhen; Zhao, Hong-Ting; Li, Hui-Hui; Ji, Mu-Huo; Li, Kuan-Yu; Yang, Jian-Jun

    2016-11-01

    Ketamine, a common anesthetic used for pediatric patients, has been shown to induce neurotoxicity and alter adolescent behaviors in rats when administered during neonatal period. However, the mechanisms underlying this kind of neurotoxicity remain largely to be determined. Herein, we studied whether the reactive oxygen species (ROS) due to the increased NOX2 mediates loss of phenotype of PV interneurons and thus contributes to long-term cognitive impairments after repeated ketamine exposures. Sprague-Dawley male rat pups received a daily administration of ketamine intraperitoneally (75 mg/kg) from postnatal day 6 (P6) to P8 for three consecutive days. For the interventional study, pups were treated with a NADPH oxidase inhibitor, apocynin (Apo). Learning and memory abilities were tested by the open field, fear conditioning, and Morris water maze on P40, P42-44, and P50-56, respectively. For histological and biochemical assays, a separate cohort of rats was killed on P9 or P60, and the brain tissues were harvested. Our results showed the upregulation of 8-OHdG and gp91/NOX2 and downregulation of PV and glutamic acid decarboxylase 67 (GAD67) after repeated ketamine exposures, which co-occurred with the long-term cognitive impairments as evidenced by the decreased freezing time to context. However, Apo treatment attenuated these abnormalities. Our results suggest that oxidative damage, probably due to the increased NOX2, mediates loss of phenotype of PV interneurons and thus contributes to long-term cognitive impairments after repeated ketamine exposures. Moreover, the inhibition of NADPH oxidase may protect against cognitive dysfunction.

  2. Effect of long-term exposure to air pollution on type 2 diabetes mellitus risk: a systemic review and meta-analysis of cohort studies.

    Science.gov (United States)

    Wang, Bin; Xu, Donghua; Jing, Zhaohai; Liu, Dawei; Yan, Shengli; Wang, Yangang

    2014-11-01

    To assess the effect of long-term exposure to air pollution on type 2 diabetes risk, a meta-analysis of prospective cohort studies was performed. Literature search was conducted with Pubmed, Embase, and Web of Science for prospective cohort studies investigating the association of type 2 diabetes risk with increments in particulate matter (PM, diametercohort studies were finally included, which involved a total of 2 37,1 907 participants and 21,095 incident cases of type 2 diabetes. Elevated risk of type 2 diabetes was significantly associated with long-term exposures to high levels of PM2.5 (RR=1.28, 95% CI 1.06-1.55, P=0.009, I2=83.5%), PM10 (RR=1.15, 95% CI 1.02-1.30, P=0.022, I2=0%), and NO2 (RR=1.12, 95% CI 1.02-1.23, P=0.015, I2=63.5%). When using standardized risk estimates, the RRs of type 2 diabetes were significant for increments in concentrations of PM2.5 (1.39 per 10 μg/m3 increment, 95% CI 1.14-1.68, P=0.001), PM10 (1.34 per 10 μg/m3 increment, 95% CI 1.22-1.47, P<0.001), and NO2 (1.11 per 10 μg/m3 increment, 95% CI 1.07-1.16, P<0.001). No obvious evidence of publication bias was observed. Long-term exposure to high levels of main air pollutants is significantly associated with elevated risk of type 2 diabetes mellitus. © 2014 European Society of Endocrinology.

  3. Minor effects of long-term ozone exposure on boreal peatland species Eriophorum vaginatum and Sphagnum papillosum

    DEFF Research Database (Denmark)

    Mörsky, SK; Haapala, JK; Rinnan, Riikka;

    2011-01-01

    The effects of long-term ozone fumigation on two common peatland plant species, a sedge Eriophorum vaginatum L. and a moss Sphagnum papillosum Lindb., were studied applying peatland microcosms. The peat cores with intact vegetation were cored from an oligotrophic pine fen and partially embedded...... not show any significant treatment effect in E. vaginatum or in S. papillosum. Total chlorophyll (a + b) concentration tended to increase in early growing season under ozone exposure. During the first growing season, elevated ozone concentration decreased methanol-extractable, UV-absorbing compounds in E...

  4. Decreased level of Nurr1 in heterozygous young adult mice leads to exacerbated acute and long-term toxicity after repeated methamphetamine exposure.

    Directory of Open Access Journals (Sweden)

    Yu Luo

    Full Text Available The abuse of psychostimulants, such as methamphetamine (METH, is prevalent in young adults and could lead to long-term adaptations in the midbrain dopamine system in abstinent human METH abusers. Nurr1 is a gene that is critical for the survival and maintenance of dopaminergic neurons and has been implicated in dopaminergic neuron related disorders. In this study, we examined the synergistic effects of repeated early exposure to methamphetamine in adolescence and reduction in Nurr1 gene levels. METH binge exposure in adolescence led to greater damage in the nigrostrial dopaminergic system when mice were exposed to METH binge later in life, suggesting a long-term adverse effect on the dopaminergic system. Compared to naïve mice that received METH binge treatment for the first time, mice pretreated with METH in adolescence showed a greater loss of tyrosine hydroxylase (TH immunoreactivity in striatum, loss of THir fibers in the substantia nigra reticulata (SNr as well as decreased dopamine transporter (DAT level and compromised DA clearance in striatum. These effects were further exacerbated in Nurr1 heterozygous mice. Our data suggest that a prolonged adverse effect exists following adolescent METH binge exposure which may lead to greater damage to the dopaminergic system when exposed to repeated METH later in life. Furthermore, our data support that Nurr1 mutations or deficiency could be a potential genetic predisposition which may lead to higher vulnerability in some individuals.

  5. Different Cellular Response of Human Mesothelial Cell MeT-5A to Short-Term and Long-Term Multiwalled Carbon Nanotubes Exposure

    Directory of Open Access Journals (Sweden)

    Li Ju

    2017-01-01

    Full Text Available Despite being a commercially important product, multiwalled carbon nanotubes (MWCNTs continue to raise concerns over human health due to their structural similarity to asbestos. Indeed, exposure to MWCNT has been shown to induce lung cancer and even mesothelioma, but contradictory results also exist. To clarify the potentially carcinogenic effects of rigid and rod-like MWCNT and to elucidate the underlying mechanisms, the effects of MWCNT on human mesothelial cell MeT-5A were examined throughout 3 months of continuous exposure, including cytotoxicity, genotoxicity, and cell motility. It was found that MWCNT did not affect MeT-5A cell proliferation at 10 μg/cm2 within 72 h treatment, but under the same condition, MWCNT induced genotoxicity and perturbed cell motility. In addition, MeT-5A cells demonstrated different cellular responses to MWCNT after short-term and long-term exposure. Taken together, our results indicated a possible carcinogenic potential for MWCNT after long-term treatment, in which Annexin family proteins might be involved.

  6. Long-term effects of early adolescent methamphetamine exposure on depression-like behavior and the hypothalamic vasopressin system in mice.

    Science.gov (United States)

    Joca, Lauren; Zuloaga, Damian G; Raber, Jacob; Siegel, Jessica A

    2014-01-01

    Methamphetamine (MA) has neurotoxic effects on the adult human brain that can lead to deficits in behavior and cognition. However, relatively little research has examined the behavioral or neurotoxic effects of MA in adolescents. The rising rates of adolescent MA use make it imperative that we understand the long-term effects of MA exposure on the adolescent brain and how these effects may differ from those seen in adults. In this study, the long-term effects of MA exposure during early adolescence on behavior and the vasopressin system in the paraventricular nucleus of the hypothalamus in late adolescent and adult male and female C57BL/6J mice were examined. MA exposure increased depression-like behavior in the Porsolt forced swim test in both late adolescent and adult male and female mice. Late adolescent male mice exposed to MA also showed a decrease in the number of vasopressin-immunoreactive neurons in the paraventricular nucleus compared to sex-matched saline-treated controls. Thus, similar to humans exposed to MA during adolescence, mice exposed to MA during adolescence show increased depression-like behavior later in life. These changes in behavior may be related to MA-induced alterations in vasopressin and the hypothalamic-pituitary-adrenal axis, especially in males.

  7. A multi-nuclide approach to quantify long-term erosion rates and exposure history through multiple glacial-interglacial cycles

    DEFF Research Database (Denmark)

    Strunk, Astrid; Larsen, Nicolaj Krog; Knudsen, Mads Faurschou;

    possible to resolve the complex pattern of exposure history under a fluctuating ice sheet. In this study, we quantify long-term erosion rates along with durations of multiple exposure periods in West Greenland by applying a novel Markov Chain Monte Carlo (MCMC) inversion approach to existing 10Be and 26Al....... The new MCMC approach allows us to constrain the most likely landscape history based on comparisons between simulated and measured cosmogenic nuclide concentrations. It is a fundamental assumption of the model that the exposure history at the site/location can be divided into two distinct regimes: i...... simulates numerous different landscape scenarios based on these four parameters and zooms in on the most plausible combination of model parameters. We apply the MCMC-model to the concentrations of 10Be and 26Al measured in previously published studies from Upernavik, Uummannaq and Sisimiut and quantify...

  8. Long-term exposure to combination antiretroviral therapy and risk of death from specific causes: no evidence for any previously unidentified increased risk due to antiretroviral therapy

    DEFF Research Database (Denmark)

    Kowalska, Justyna D; Reekie, Joanne; Mocroft, Amanda

    2012-01-01

    BACKGROUND:: Despite the known substantial benefits of combination antiretroviral therapy (cART), cumulative adverse effects could still limit the overall long-term treatment benefit. Therefore we investigated changes in the rate of death with increasing exposure to cART. METHODS:: 12069 patients...... were followed from baseline, which was defined as the time of starting cART or enrolment into EuroSIDA whichever occurred later, until death or six months after last follow-up visit. Incidence rates (IR) of death were calculated per 1000 person-years of follow-up (PYFU) and stratified by time...... of exposure to cART (=3 antiretrovirals): 8 years. Duration of cART exposure was the cumulative time actually receiving cART. Poisson regression models were fitted for each cause of death separately. RESULTS:: 1297 patients died during 70613 PYFU (IR 18.3 per 1000 PYFU, 95%CI: 17.4-19.4), 413 due to AIDS (5...

  9. Long term effects of murine postnatal exposure to decabromodiphenyl ether (BDE-209) on learning and memory are dependent upon APOE polymorphism and age

    DEFF Research Database (Denmark)

    Reverte, Ingrid; Klein, Anders Bue; Domingo, José L

    2014-01-01

    exposure to BDE-209 induced long term effects in spatial learning, which were dependent upon age, sex and apoE genotype; these effects were more evident in apoE3 mice. BDNF levels were lower in the frontal cortex of apoE4 mice and higher in the hippocampus of exposed mice, independent of the genotype....... The results of the present study provide evidence of long-lasting effects in spatial learning and memory after early exposure to BDE-209. Developmental exposure to this neurotoxicant may contribute to cognitive decline and abnormal aging....... with varied vulnerability for the development of neurodegenerative diseases. On postnatal day 10, transgenic mice of both sexes carrying apoE2, apoE3 and apoE4 were orally exposed to 0, 10 or 30mg/kg of BDE-209. Spatial reference memory was assessed in a Morris Water Maze (MWM) task at 4 and 12months of age...

  10. Relationship between long-term exposure to low-level arsenic in drinking water and the prevalence of abnormal blood pressure.

    Science.gov (United States)

    Zhang, Chuanwu; Mao, Guangyun; He, Suxia; Yang, Zuopeng; Yang, Wei; Zhang, Xiaojing; Qiu, Wenting; Ta, Na; Cao, Li; Yang, Hui; Guo, Xiaojuan

    2013-11-15

    Arsenic increases the risk and incidence of cardiovascular disease. To explore the impact of long-term exposure to low-level arsenic in drinking water on blood pressure including pulse pressure (PP) and mean arterial blood pressure (MAP), a cross-sectional study was conducted in 2010 in which the blood pressure of 405 villagers was measured, who had been drinking water with an inorganic arsenic content 63-3.35) increase in the group with >30-50 years of arsenic exposure and a 2.95-fold (95%CI: 1.31-6.67) increase in the group with >50 years exposure. Furthermore, the odds ratio for prevalence of abnormal PP and MAP were 1.06 (95%CI: 0.24-4.66) and 0.87 (95%CI: 0.36-2.14) in the group with >30-50 years of exposure, and were 2.46 (95%CI: 0.87-6.97) and 3.75 (95%CI: 1.61-8.71) for the group with >50 years exposure, compared to the group with arsenic exposure ≤ 30 years respectively. Significant trends for Hypertension (parsenic exposure population, and significantly increases with the duration of arsenic exposure.

  11. Long-term effects of prenatal atrazine exposure on physiology, body composition, and stress reactivity in rats

    Science.gov (United States)

    Low birth weight in humans is associated with increased risk of coronary heart disease, hypertension, and diabetes in adulthood. Experimental studies have also reported that undernutrition, stress or exposure to glucocorticoids during pregnancy is associated with hypertension, gl...

  12. Neonatal exposure to brominated flame retardant BDE-47 reduces long-term potentiation and postsynaptic protein levels in mouse hippocampus

    NARCIS (Netherlands)

    Dingemans, Milou M. L.; Ramakers, Geert M. J.; Gardoni, Fabrizio; van Kleef, Regina G. D. M.; Bergman, Ake; Di Luca, Monica; van den Berg, Martin; Westerink, Remco H. S.; Wijverberg, Henk P. M.

    2007-01-01

    BACKGROUND: Increasing environmental levels of brominated flame retardants raise concern about possible adverse effects, particularly through early developmental exposure. OBJECTIVE: The objective of this research was to investigate neturodevelopmental mechanisms underlying previously observed behav

  13. Long-term effects of prenatal atrazine exposure on physiology, body composition, and stress reactivity in rats

    Science.gov (United States)

    Low birth weight in humans is associated with increased risk of coronary heart disease, hypertension, and diabetes in adulthood. Experimental studies have also reported that undernutrition, stress or exposure to glucocorticoids during pregnancy is associated with hypertension, gl...

  14. Morphological and physiological changes in mature in vitro neuronal networks towards exposure to short-, middle- or long-term simulated microgravity.

    Science.gov (United States)

    Pani, Giuseppe; Samari, Nada; Quintens, Roel; de Saint-Georges, Louis; Meloni, Mariantonia; Baatout, Sarah; Van Oostveldt, Patrick; Benotmane, Mohammed Abderrafi

    2013-01-01

    One of the objectives of the current international space programmes is to investigate the possible effects of the space environment on the crew health. The aim of this work was to assess the particular effects of simulated microgravity on mature primary neuronal networks and specially their plasticity and connectivity. For this purpose, primary mouse neurons were first grown for 10 days as a dense network before being placed in the Random Positioning Machine (RPM), simulating microgravity. These cultures were then used to investigate the impact of short- (1 h), middle- (24 h) and long-term (10 days) exposure to microgravity at the level of neurite network density, cell morphology and motility as well as cytoskeleton properties in established two-dimensional mature neuronal networks. Image processing analysis of dense neuronal networks exposed to simulated microgravity and their subsequent recovery under ground conditions revealed different neuronal responses depending on the duration period of exposure. After short- and middle-term exposures to simulated microgravity, changes in neurite network, neuron morphology and viability were observed with significant alterations followed by fast recovery processes. Long exposure to simulated microgravity revealed a high adaptation of single neurons to the new gravity conditions as well as a partial adaptation of neuronal networks. This latter was concomitant to an increase of apoptosis. However, neurons and neuronal networks exposed for long-term to simulated microgravity required longer recovery time to re-adapt to the ground gravity. In conclusion, a clear modulation in neuronal plasticity was evidenced through morphological and physiological changes in primary neuronal cultures during and after simulated microgravity exposure. These changes were dependent on the duration of exposure to microgravity.

  15. Long-Term Consequences of Developmental Alcohol Exposure on Brain Structure and Function: Therapeutic Benefits of Physical Activity

    Directory of Open Access Journals (Sweden)

    Gillian F. Hamilton

    2012-12-01

    Full Text Available Developmental alcohol exposure both early in life and during adolescence can have a devastating impact on normal brain structure and functioning, leading to behavioral and cognitive impairments that persist throughout the lifespan. This review discusses human work as well as animal models used to investigate the effect of alcohol exposure at various time points during development, as well as specific behavioral and neuroanatomical deficits caused by alcohol exposure. Further, cellular and molecular mediators contributing to these alcohol-induced changes are examined, such as neurotrophic factors and apoptotic markers. Next, this review seeks to support the use of aerobic exercise as a potential therapeutic intervention for alcohol-related impairments. To date, few interventions, behavioral or pharmacological, have been proven effective in mitigating some alcohol-related deficits. Exercise is a simple therapy that can be used across species and also across socioeconomic status. It has a profoundly positive influence on many measures of learning and neuroplasticity; in particular, those measures damaged by alcohol exposure. This review discusses current evidence that exercise may mitigate damage caused by developmental alcohol exposure and is a promising therapeutic target for future research and intervention strategies.

  16. Effect of long-term hydrogen exposure on the mechanical properties of polymers used for pipes and tested in pressurized hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Castagnet, Sylvie, E-mail: sylvie.castagnet@ensma.fr [Institut P' (UPR CNRS 3346), CNRS-ENSMA-Universite de Poitiers, Departement de Physique et Mecanique des Materiaux, ENSMA, 1 Avenue Clement Ader, BP40109, 86961 Futuroscope cedex (France); Grandidier, Jean-Claude; Comyn, Mathieu; Benoit, Guillaume [Institut P' (UPR CNRS 3346), CNRS-ENSMA-Universite de Poitiers, Departement de Physique et Mecanique des Materiaux, ENSMA, 1 Avenue Clement Ader, BP40109, 86961 Futuroscope cedex (France)

    2012-01-15

    The influence of long-term exposure to hydrogen on the mechanical properties of polymers needs to be characterized for a reliable design of storage or transport facilities. However, mechanical tests in hydrogen atmosphere have been rarely reported. In the present study, two possible effects of hydrogen on tensile properties have been investigated in two polymers currently used for gas transport i.e. polyethylene (PE) and polyamide 11 (PA11): the mechanics-diffusion coupling and the influence of long-term exposure to hydrogen. Tensile tests in hydrogen atmosphere (30 bars) and atmospheric air at room temperature were compared, in the as-received materials as well as after aging in various conditions (pressure, temperature and duration). Results showed that the influence of hydrogen was prevalent neither on the tensile behavior nor on microstructure changes. This suggested that the design of hydrogen-dedicated parts could be based on data obtained in atmospheric air, even for long-term use. - Highlights: Black-Right-Pointing-Pointer Coupling between hydrogen diffusion and mechanics was addressed in polymers currently used for piping. Black-Right-Pointing-Pointer As-received and 13-month hydrogen-exposed polyethylene and polyamide 11 were tested. Black-Right-Pointing-Pointer Tensile tests in pressurized hydrogen and atmospheric air at ambient temperature were compared. Black-Right-Pointing-Pointer Microstructure changes during aging were tracked by standard calorimetry. Black-Right-Pointing-Pointer The influence of hydrogen was found to be prevalent neither on the tensile behavior nor on microstructure changes.

  17. Everything fine so far? Physical and mental health in HIV-infected patients with virological success and long-term exposure to antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    Gesa Erdbeer

    2014-11-01

    Full Text Available Introduction: Little is known about the well-being on long-term exposure to antiretroviral therapy. The ACTG Augmented Symptoms Distress Module (ASDM is a validated tool which measures the presence of a total of 22 symptoms seen with HIV and quantifies the extent to which they cause distress to the patient. Methods: ELBE was a cross-sectional study that consecutively included adult HIV-infected patients presenting with viral suppression (<50 HIV RNA copies/mL and ART exposure for at least five years. Patients were evaluated by four different questionnaires, including ASDM. Results: Of a total of 894 patients included in the three participating ELBE centres, complete data on ASDM were available for 698 patients (626 male, 69 female, 3 transsexual. Median age was 49.7 years (range, 23.3–82.5 years and median exposure to ART was 11.5 years (range, 5–28 years. Median CD4 T-cell counts had increased from a CD4 nadir of 180 to currently 640 cells/µL. Despite immunological and virological success, a high degree of symptom-related distress was noted in this patient population. In total, 63.8% and 36.3% of the patients had at least one “bothersome” or one “very bothersome” symptom, respectively. The symptoms most frequently reported to be “bothersome” or “very bothersome” were fatigue and energy loss (18.5% and 11.0% respectively, insomnia (12.8% and 11.6%, sadness and depression (13.0% and 10.0%, sexual dysfunction (12.0% and 10.0%, and changes in body appearance (11.0% and 10.9%. There was no association between the degree of symptom-related distress and gender, age or CD4 T-cell nadir. However, the history of AIDS-defining illnesses, comorbidities such as depression but also the duration of ART were significantly associated with a higher overall symptom summary score and with a higher frequency of symptoms. For example, in patients with at least 15 years of ART exposure, only 27.3% of the patients did not report at least one

  18. Measurement of 210Po atoms content in glass as an indicator of long-term exposure to radon.

    Science.gov (United States)

    Jankowski, J; Olszewski, J; Skubalski, J

    1999-01-01

    Measurements of exposure to radon are performed using numerous research methods which register either temporary or periodic radon concentrations. The method presented below allows for the estimation of average radon concentration in the past. This is possible due to indirect measurement of the contents of 210Pb embedded in glass structure. The half-life of 210Pb is about 22 years. A number of exposures of window glass to radon have been carried out in laboratory conditions (radon chamber) and the obtained results were used to calculate the coefficient that renders it possible to define global indoor exposure to radon. The registration was made using a track detector CR-39, which records alpha particles resulting from the disintegration of 210Po, one of 222Rn decay products.

  19. Short- and long-term consequences of larval stage exposure to constantly and ephemerally elevated carbon dioxide for marine bivalve populations

    Directory of Open Access Journals (Sweden)

    C. J. Gobler

    2013-04-01

    Full Text Available While larval bivalves are highly sensitive to ocean acidification, the basis for this sensitivity and the longer-term implications of this sensitivity are unclear. Experiments were performed to assess the short-term (days and long-term (months consequences of larval stage exposure to varying CO2 concentrations for calcifying bivalves. Higher CO2 concentrations depressed both calcification rates assessed using 45Ca uptake and RNA : DNA ratios in Mercenaria mercenaria and Argopecten irradians larvae with RNA : DNA ratios being highly correlated with larval growth rates (r2>0.9. These findings suggested that high CO2 has a cascading negative physiological impact on bivalve larvae stemming in part from lower calcification rates. Exposure to elevated CO2 during the first four days of larval development significantly depressed A. irradians larval survival rates, while a 10-day exposure later in larval development did not, demonstrating the extreme CO2 sensitivity of bivalve larvae during first days of development. Short- (weeks and long-term (10 month experiments revealed that individuals surviving exposure to high CO2 during larval development grew faster when exposed to normal CO2 as juveniles compared to individuals reared under ambient CO2 as larvae. These increased growth rates could not, however, overcome size differences established during larval development, as size deficits of individuals exposed to even moderate levels of CO2 as larvae were evident even after 10 months of growth under normal CO2 concentrations. This "legacy effect" emphasizes the central role larval stage CO2 exposure can play in shaping the success of modern-day bivalve populations.

  20. Brief exposure to methamphetamine (METH) and phencyclidine (PCP) during late development leads to long-term learning deficits in rats.

    Science.gov (United States)

    White, Ilsun M; Minamoto, Takehiro; Odell, Joseph R; Mayhorn, Joseph; White, Wesley

    2009-04-17

    Exposure to methamphetamine (METH) and phencyclidine (PCP) during early development is thought to produce later behavioral deficits. We postulated that exposure to METH and PCP during later development would produce similar behavioral deficits, particularly learning deficits in adulthood. Wistar rats were treated with METH (9 mg/kg), PCP (9 mg/kg), or saline during later development, postnatal days (PD) 50-51, and subsequent behavioral changes were examined including: locomotor activity during the acute drug state (PD 50-51) and the post-drug phase (PD 50-80); social interaction on PD 54-80; and spatial discrimination and reversal in adulthood (after PD 90). METH and PCP differentially affected locomotion during the acute state, but not during the post-drug phase. METH decreased social interaction throughout tests two weeks after drug treatment, whereas PCP decreased social interaction only during the first 8 min of tests. Neither METH nor PCP impaired initial acquisition of spatial discrimination. However, reversal was significantly impaired by PCP, whereas METH produced a mild deficit, compared to controls. Our data provide evidence that exposure to PCP and METH during later development lead to enduring cognitive deficits in adulthood. Selective impairment of reversal may reflect neurological damage in the prefrontal cortex due to early exposure to drugs.

  1. Effects of Long-Term Low-Level Radiofrequency Radiation Exposure on Rats. Volume 1. Design, Facilities, and Procedures.

    Science.gov (United States)

    1983-09-01

    8217* Power Generation and Distribution Each exposure room was equipped with two 2450-MHz pulsed microwave sources ( Epsco , model PG5KB, Trenton, NJ), each...METERS RS 232 COMMUNICATIONS WITH MASTER 4-DIGIT L ED DISPLAY FROM ALCOVE CONTROL SWITCHES TTL SYNC EPSCO 12-CHANNEL TEMP MONITOR OSCLLSCPE MICROWAVE

  2. Elevated NMDA receptor levels and enhanced postsynaptic long-term potentiation induced by prenatal exposure to valproic acid

    DEFF Research Database (Denmark)

    Rinaldi, Tania; Kulangara, Karina; Antoniello, Katia

    2007-01-01

    Valproic acid (VPA) is a powerful teratogen causing birth defects in humans, including autism spectrum disorder (ASD), if exposure occurs during the first trimester of embryogenesis. Learning and memory alterations are common symptoms of ASD, but underlying molecular and synaptic alterations rema...

  3. Long-term exposure to xenoestrogens alters some brain monoamines and both serum thyroid hormones and cortisol levels in adult male rats

    Directory of Open Access Journals (Sweden)

    Nashwa M. Saied

    2014-10-01

    Full Text Available The present study was designed to examine the effect of long-term treatment with the phytoestrogen soy isoflavone [(SIF; 43 mg/kg body weight/day] and/or the plastics component bisphenol-A [(BPA; 3 mg/kg body weight/day] on some monoamines in the forebrain and both serum thyroid hormones and cortisol levels of adult rats. Significant increases in serotonin (5-HT and norepinephrine (NE level, and significant decreases in 5-hydroxyindoleacetic acid (5-HIAA level and 5-HIAA/5-HT ratio, were observed after treatment with SIF or BPA. Level of dopamine (DA was increased in SIF-treated group and decreased in BPA-treated group. Activity of monoamine oxidase (MAO was decreased in all treated groups. The level of serum thyroid hormones (fT3 and fT4 was increased after treatment with SIF and decreased after exposure to BPA, while cortisol level was increased in all treated groups. It may be concluded that long-term exposure to SIF or BPA disrupts monoamine levels in the forebrain of adult rats through alteration in the metabolic pathways of amines and disorders of thyroid hormones and cortisol levels.

  4. Short- and Long-Term Effects of Prenatal Exposure to Iron Oxide Nanoparticles: Influence of Surface Charge and Dose on Developmental and Reproductive Toxicity.

    Science.gov (United States)

    Di Bona, Kristin R; Xu, Yaolin; Gray, Marquita; Fair, Douglas; Hayles, Hunter; Milad, Luckie; Montes, Alex; Sherwood, Jennifer; Bao, Yuping; Rasco, Jane F

    2015-12-18

    Iron oxide nanoparticles (NPs) are commonly utilized for biomedical, industrial, and commercial applications due to their unique properties and potential biocompatibility. However, little is known about how exposure to iron oxide NPs may affect susceptible populations such as pregnant women and developing fetuses. To examine the influence of NP surface-charge and dose on the developmental toxicity of iron oxide NPs, Crl:CD1(ICR) (CD-1) mice were exposed to a single, low (10 mg/kg) or high (100 mg/kg) dose of positively-charged polyethyleneimine-Fe₂O₃-NPs (PEI-NPs), or negatively-charged poly(acrylic acid)-Fe₂O₃-NPs (PAA-NPs) during critical windows of organogenesis (gestation day (GD) 8, 9, or 10). A low dose of NPs, regardless of charge, did not induce toxicity. However, a high exposure led to charge-dependent fetal loss as well as morphological alterations of the uteri (both charges) and testes (positive only) of surviving offspring. Positively-charged PEI-NPs given later in organogenesis resulted in a combination of short-term fetal loss (42%) and long-term alterations in reproduction, including increased fetal loss for second generation matings (mice exposed in utero). Alternatively, negatively-charged PAA-NPs induced fetal loss (22%) earlier in organogenesis to a lesser degree than PEI-NPs with only mild alterations in offspring uterine histology observed in the long-term.

  5. Long-term slip rate of the southern San Andreas Fault, from 10Be-26Al surface exposure dating of an offset alluvial fan

    Energy Technology Data Exchange (ETDEWEB)

    der Woerd, J v; Klinger, Y; Sieh, K; Tapponnier, P; Ryerson, F; M?riaux, A

    2006-01-13

    We determine the long-term slip rate of the southern San Andreas Fault in the southeastern Indio Hills using {sup 10}Be and {sup 26}Al isotopes to date an offset alluvial fan surface. Field mapping complemented with topographic data, air photos and satellite images allow to precisely determine piercing points across the fault zone that are used to measure an offset of 565 {+-} 80 m. A total of twenty-six quartz-rich cobbles from three different fan surfaces were collected and dated. The tight cluster of nuclide concentrations from 19 samples out of 20 from the offset fan surface implies a simple exposure history, negligible prior exposure and erosion, and yield an age of 35.5 {+-} 2.5 ka. The long-term slip rate of the San Andreas Fault south of Biskra Palms is thus 15.9 {+-} 3.4 mm/yr. This rate is about 10 mm/yr slower than geological (0-14 ka) and short-term geodetic estimates for this part of the San Andreas Fault implying changes in slip rate or in faulting behavior. This result puts new constraints on the slip rate of the San Jacinto and on the Eastern California Shear Zone for the last 35 ka. Our study shows that more sites along the major faults of southern California need to be targeted to better constrain the slip-rates over different time scales.

  6. EXPOSURE DOSES ASSESSMENT OF POPULATION AT LONG-TERM PERIOD AFTER THE CHERNOBYL ACCIDENT: INTERNATIONAL COLLABORATION EXPERIENCE

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2013-01-01

    Full Text Available The study which had been conducted in the period from 1990 to 2000’s in the settlements ofGomelregion showed that the average internal exposure doses of population living in the settlements situated on territories with equal levels of contamination density were considerably different. The reasons for the difference have been revealed. It was shown that not only radiation contamination of territory but also a range of factors of non-radiation origin have influence on formation of internal exposure dose. The hypothesis has been approved that internal exposure dose of each individual and also of each family has its certain place, constant in time at a dose distribution curve. This appropriateness had been used as a methodological basis for reconstruction of subjects’ individual doses for any time period. Method for estimating the average annual effective exposure doses of inhabitants living in contaminated settlements of theBelarusRepublichad been developed. The results of the Whole Body Counter measurements had been used for direct assessment of internal exposure dose and as the basis for developing a model. Model for the dose estimation is based on the classification of settlements according to regional characteristics of soil, which cause 137Cs in taking with locally produced foodstuff. The model is also based on regression of daily 137Cs intake on the density contamination of the soil for each region. The effect of the indirect factors on the dose forming had been taken into account: the number of inhabitants and the area of forest around the settlement. According to the developed method, there had been created a Catalog of Average Annual Effective Doses of Residents of the Belarus Republic.

  7. Vibrio anguillarum Is Genetically and Phenotypically Unaffected by Long-Term Continuous Exposure to the Antibacterial Compound Tropodithietic Acid

    DEFF Research Database (Denmark)

    Rasmussen, Bastian Barker; Grotkjær, Torben; D'Alvise, Paul;

    2016-01-01

    -pathogenic vibrios in fish larvae and live feed cultures for fish larvae. The antibacterial compound tropodithietic acid (TDA), an antiporter that disrupts the proton motive force, is key in the antibacterial activity of several roseobacters. Introducing probiotics on a larger scale requires understanding of any...... potential side effects of long-term exposure of the pathogen to the probionts or any compounds they produce. Here we exposed the fish pathogen Vibrio anguillarum to TDA for several hundred generations in an adaptive evolution experiment. No tolerance or resistance arose during the 90 days of exposure......, and whole-genome sequencing of TDA-exposed lineages and clones revealed few mutational changes, compared to lineages grown without TDA. Amino acid-changing mutations were found in two to six different genes per clone; however, no mutations appeared unique to the TDA-exposed lineages or clones. None...

  8. Effect of long term exposure of low doses of lambda- cyhalothrin on the level of lipid peroxidation and antioxidant enzymes of the pregnant rats and their offspring

    Directory of Open Access Journals (Sweden)

    Kadir Tukhtaev

    2012-12-01

    Full Text Available Lambda- cyhalothrin (LCT is a pyrethroid insecticide class, which is widely used for pest control in agriculture, public health, home and garden. In the present study we investigated the effect of long term exposure of low doses of the LCT on the state of lipid peroxidation and antioxidant protection of pregnant rats and their offspring. It was revealed, that prolonged exposure of lambda-cyhalothrin leads to the development of oxidative stress in both of pregnant females and their offspring. The highest level of lipid peroxidation detected on 14-21 days of pregnancy, which was accompanied by a reduction in activity of antioxidant enzymes. In the offspring highest level of oxidative stress observed on 7-14 days of lactation. The degree of oxidative stress in offspring decreases as the cessation of receipt of a pesticide or its toxic metabolites in breast milk.

  9. Could maternal exposure to the antidepressants fluoxetine and St. John's Wort induce long-term reproductive effects on male rats?

    Science.gov (United States)

    Vieira, Milene Leivas; Hamada, Renata Yumi; Gonzaga, Natalia Ignácio; Bacchi, Andre Demambre; Barbieri, Mainara; Moreira, Estefânia Gastaldello; Mesquita, Suzana de Fátima Paccola; Gerardin, Daniela Cristina Ceccatto

    2013-01-01

    Based on the limited number of studies that have investigated the adverse effects of maternal treatment with antidepressants on the development of male descendents, this study was carried out in rat in order to evaluate if maternal exposure to fluoxetine (FLX) or St. John's Wort (SJW) could disrupt the development of male offspring. The dams were treated daily, by gavage, with 7.5 mg/kg of FLX or 100 mg/kg SJW during pregnancy and lactation. The reproductive and behavior parameters were analyzed in male pups. Results showed decreases in the weight of the full seminal vesicle and in the number of spermatozoa. Moreover, FLX-exposed pups presented reduced seminiferous epithelium height and diameter of seminiferous tubules. The present study shows that maternal exposure to FLX, but not SJW could interfere on reproductive parameters in adult male rats.

  10. Effect of long-term exposure of SH-SY5Y cells to morphine: a whole cell proteomic analysis

    Directory of Open Access Journals (Sweden)

    Moulédous Lionel

    2006-12-01

    Full Text Available Abstract Background Opiate addiction reflects plastic changes that endurably alter synaptic transmission within relevant neuronal circuits. The biochemical mechanisms of these adaptations remain largely unknown and proteomics-based approaches could lead to a broad characterization of the molecular events underlying adaptations to chronic drug exposure. Results Thus, we have started proteomic analyses of the effects of chronic morphine exposure in a recombinant human neuroblastoma SH-SY5Y clone that stably overexpresses the μ-opioid receptor. Cells were treated with morphine for 6, 24 and 72 hours, the proteins were separated by 2-D gel electrophoresis and stained with Coomassie blue, and the protein map was compared with that obtained from untreated cells. Spots showing a statistically significant variation were selected for identification using mass spectrometric analyses. Conclusion A total of 45 proteins were identified, including proteins involved in cellular metabolism, cytoskeleton organization, vesicular trafficking, transcriptional and translational regulation, and cell signaling.

  11. Histological changes in the nasal mucosa in rats after long-term exposure to formaldehyde and wood dust.

    Science.gov (United States)

    Holmström, M; Wilhelmsson, B; Hellquist, H

    1989-01-01

    Wood dust is a well known nasal carcinogen in man, as formaldehyde is in rats. In certain occupational environments, combined exposure to wood dust and formaldehyde is common. Little is known about the effects of this combination. A pilot study was performed on four groups of Sprague-Dawley rats: one exposed to wood dust (25 mg/m3), another to formaldehyde (12.4 ppm) and a third to both wood dust and formaldehyde; the fourth group served a control group. After 104 weeks of exposure the nose and lungs were examined histologically. One well differentiated squamous cell carcinoma was found in the formaldehyde group. Squamous cell metaplasia was found significantly more often among the formaldehyde-exposed rats. Squamous cell metaplasia with dysplasia was most frequently observed, however, in the group exposed to both formaldehyde and wood dust. There were also significantly more rats with pulmonary emphysema in the groups exposed to wood dust than in the other groups.

  12. Long-term alterations of striatal parvalbumin interneurons in a rat model of early exposure to alcohol

    OpenAIRE

    De Giorgio Andrea; Comparini Sara E; Intra Francesca; Granato Alberto

    2012-01-01

    Abstract Background Exposure to alcohol in utero is a known cause of mental retardation. Although a certain degree of motor impairment is always associated with fetal alcohol spectrum disorder, little is known about the neurobiological basis of the defective motor control. We have studied the striatal interneurons containing parvalbumin in a rat model of fetal alcohol spectrum disorder. Methods Newborn rats received ethanol by inhalation from postnatal day two through six and parvalbumin stri...

  13. Long-term alterations of striatal parvalbumin interneurons in a rat model of early exposure to alcohol

    OpenAIRE

    De Giorgio, Andrea; Comparini, Sara E; Intra, Francesca Sangiuliano; Granato, Alberto

    2012-01-01

    Background Exposure to alcohol in utero is a known cause of mental retardation. Although a certain degree of motor impairment is always associated with fetal alcohol spectrum disorder, little is known about the neurobiological basis of the defective motor control. We have studied the striatal interneurons containing parvalbumin in a rat model of fetal alcohol spectrum disorder. Methods Newborn rats received ethanol by inhalation from postnatal day two through six and parvalbumin striatal neur...

  14. Effects of long-term exposure to 900 megahertz electromagnetic field on heart morphology and biochemistry of male adolescent rats.

    Science.gov (United States)

    Kerimoğlu, G; Mercantepe, T; Erol, H S; Turgut, A; Kaya, H; Çolakoğlu, S; Odacı, E

    2016-08-11

    The pathological effects of exposure to an electromagnetic field (EMF) during adolescence may be greater than those in adulthood. We investigated the effects of exposure to 900 MHz EMF during adolescence on male adult rats. Twenty-four 21-day-old male rats were divided into three equal groups: control (Cont-Gr), sham (Shm-Gr) and EMF-exposed (EMF-Gr). EMF-Gr rats were placed in an EMF exposure cage (Plexiglas cage) for 1 h/day between postnatal days 21 and 59 and exposed to 900 MHz EMF. Shm-Gr rats were placed inside the Plexiglas cage under the same conditions and for the same duration, but were not exposed to EMF. All animals were sacrificed on postnatal day 60 and the hearts were extracted for microscopic and biochemical analyses. Biochemical analysis showed increased levels of malondialdehyde and superoxide dismutase, and reduced glutathione and catalase levels in EMF-Gr compared to Cont-Gr animals. Hematoxylin and eosin stained sections from EMF-Gr animals exhibited structural changes and capillary congestion in the myocardium. The percentage of apoptotic myocardial cells in EMF-Gr was higher than in either Shm-Gr or Cont-Gr animals. Transmission electron microscopy of myocardial cells of EMF-Gr animals showed altered structure of Z bands, decreased myofilaments and pronounced vacuolization. We found that exposure of male rats to 900 MHz EMF for 1 h/day during adolescence caused oxidative stress, which caused structural alteration of male adolescent rat heart tissue.

  15. Gulf War agent exposure causes impairment of long-term memory formation and neuropathological changes in a mouse model of Gulf War Illness.

    Directory of Open Access Journals (Sweden)

    Zuchra Zakirova

    Full Text Available Gulf War Illness (GWI is a chronic multisymptom illness with a central nervous system component such as memory deficits, neurological, and musculoskeletal problems. There are ample data that demonstrate that exposure to Gulf War (GW agents, such as pyridostigmine bromide (PB and pesticides such as permethrin (PER, were key contributors to the etiology of GWI post deployment to the Persian GW. In the current study, we examined the consequences of acute (10 days exposure to PB and PER in C57BL6 mice. Learning and memory tests were performed at 18 days and at 5 months post-exposure. We investigated the relationship between the cognitive phenotype and neuropathological changes at short and long-term time points post-exposure. No cognitive deficits were observed at the short-term time point, and only minor neuropathological changes were detected. However, cognitive deficits emerged at the later time point and were associated with increased astrogliosis and reduction of synaptophysin staining in the hippocampi and cerebral cortices of exposed mice, 5 months post exposure. In summary, our findings in this mouse model of GW agent exposure are consistent with some GWI symptom manifestations, including delayed onset of symptoms and CNS disturbances observed in GWI veterans.

  16. A case-control study of long-term exposure to ambient volatile organic compounds and lung cancer in Toronto, Ontario, Canada.

    Science.gov (United States)

    Villeneuve, Paul J; Jerrett, Michael; Brenner, Darren; Su, Jason; Chen, Hong; McLaughlin, John R

    2014-02-15

    Few studies have investigated associations between nonoccupational exposure to ambient volatile organic compounds and lung cancer. We conducted a case-control study of 445 incident lung cancers and 948 controls (523 hospital, 425 general population) in Toronto, Ontario, Canada, between 1997 and 2002. Participants provided information on several risk factors, including tobacco use, secondhand exposure to cigarette smoke, obesity, and family history of cancer. Exposure to benzene, hydrocarbons, and nitrogen dioxide was estimated using land-use regression models. Exposures were linked to residential addresses to estimate exposure at the time of interview, 10 years before interview, and across past residences (time-weighted average). Logistic regression was used to estimate adjusted odds ratios. Analyses involving the population-based controls found that an interquartile-range increase in the time-weighted average benzene concentration (0.15 µg/m(3)) across previous residences was associated with lung cancer (odds ratio = 1.84, 95% confidence interval: 1.26, 2.68). Similarly, an interquartile-range increase in the time-weighted average nitrogen dioxide concentration (4.8 ppb) yielded an odds ratio of 1.59 (95% confidence interval: 1.19, 2.12). Our study suggests that long-term exposure to ambient volatile organic compounds and nitrogen dioxide at relatively low concentrations is associated with lung cancer. Further work is needed to evaluate joint relationships between these pollutants, smoking, and lung cancer.

  17. Long term dietary methoxychlor exposure in rats increases sodium solution consumption but has few effects on other sexually dimorphic behaviors.

    Science.gov (United States)

    Flynn, K M; Delclos, K B; Newbold, R R; Ferguson, S A

    2005-09-01

    Methoxychlor is an insecticide with estrogen-like activity, thus exposure during development might cause sexually dimorphic behavioral alterations. To evaluate this, pregnant rats consumed diets containing 0, 10, 100 or 1000 ppm methoxychlor from gestational day 7, and offspring continued on these diets until postnatal day (PND) 77. Assessments of sexually dimorphic behaviors in offspring indicated that intake of a 3.0% sodium chloride solution was significantly increased (41%) in males and females of the 1000 ppm group. No treatment group differed from controls in open field nor running wheel activity, play behavior, nor 0.3% saccharin solution intake. Offspring of the 1000 ppm group showed significantly decreased body weight, reaching 17% less than controls at PND 77, but not clearly related to their salt solution intake. During pregnancy, 1000 ppm dams consumed 23% less food and weighed 10% less than controls, but this did not affect litter outcomes. These results indicate that in rodents, developmental and chronic exposure to dietary methoxychlor alters the sexually dimorphic behavior of salt-solution intake in young adults of both sexes. Similar behavioral alterations with other xenoestrogens, and the potential for interactions among xenoestrogens, suggest that this report may minimize the true effects of dietary methoxychlor exposure.

  18. Long-term nose-only cigarette smoke exposure induces emphysema and mild skeletal muscle dysfunction in mice

    Directory of Open Access Journals (Sweden)

    Manuela Rinaldi

    2012-05-01

    Mouse models of chronic obstructive pulmonary disease (COPD focus on airway inflammation and lung histology, but their use has been hampered by the lack of pulmonary function data in their assessment. Systemic effects such as muscle dysfunction are also poorly modeled in emphysematous mice. We aimed to develop a cigarette-smoke-induced emphysema mouse model in which serial lung function and muscular dysfunction could be assessed, allowing the disease to be monitored more appropriately. C57Bl6 mice were nose-only exposed to cigarette smoke or filtered air for 3–6 months. Lung function tests were repeated in the same mice after 3 and 6 months of cigarette smoke or air exposure and compared with lung histological changes. Contractile properties of skeletal muscles and muscle histology were also determined at similar time points in separate groups of mice. Serial lung function measurements documented hyperinflation after 3 and 6 months of cigarette smoke exposure, with a significant 31–37% increase in total lung capacity (TLC and a significant 26–35% increase in compliance (Cchord when compared with animals exposed to filtered air only (P<0.001 after 3 and after 6 months. These functional changes preceded the changes in mean linear intercept, which became only significant after 6 months of cigarette smoke exposure and which correlated very well with TLC (r=0.74, P=0.004 and Cchord (r=0.79, P=0.001. After 6 months of cigarette smoke exposure, a significant fiber-type shift from IIa to IIx/b was also observed in the soleus muscle (P<0.05, whereas a 20% reduction of force was present at high stimulation frequencies (80 Hz; P=0.09. The extensor digitorum longus (EDL muscle was not affected by cigarette smoke exposure. These serial pulmonary function variables are sensitive outcomes to detect emphysema progression in a nose-only cigarette-smoke-exposed animal model of COPD. In this model, muscular changes became apparent only after 6 months, particularly in muscles

  19. Effect of a long-term exposure to concentrated sucrose and maltodextrin solutions on the preference, appetence, feed intake and growth performance of post-weaned piglets.

    Science.gov (United States)

    Guzmán-Pino, Sergio A; Solà-Oriol, David; Figueroa, Jaime; Dwyer, Dominic M; Pérez, José F

    2015-03-15

    Commercial pigs display an innate attraction for sweet taste compounds. However, the impact of long-term availability to supplementary carbohydrate solutions on their general feeding behavior has not been examined. In this work we assess the effect of 12-days exposure to 16% sucrose and 16% maltodextrin solutions on the feed intake and growth performance of piglets, and on their preference and appetence for sweet or protein solutions. The innate preference of piglets was assessed by an initial choice test between 2% sucrose and 2% animal plasma solutions for a period of three minutes. Piglets showed higher intake and preference for 2% sucrose than for 2% animal plasma. In Experiment 1, piglets were then free-offered a 16% sucrose solution as a supplement to the diet, showing a higher intake of it than water and a reduction in feed intake and weight gain. A similar situation occurred during the last days of free-exposure to a 16% maltodextrin solution in Experiment 2. The choice test between 2% sucrose and 2% animal plasma solution was repeated after the exposure to the concentrated solutions. In both experiments, a reduction in the initial preference for 2% sucrose was observed. Similarly, piglets that had previous access to the 16% sucrose and 16% maltodextrin solutions showed a decrease in the appetence for 2% sucrose in comparison with that for 2% animal plasma, as measured by a one-pan test at the end of the experiments. It is concluded that long-term exposure to concentrated sucrose and maltodextrin solutions reduces feed intake and growth in weanling piglets, and also reverses their innate preference and appetence for dilute sweet over protein solutions.

  20. Alcohol dehydrogenase and cytochrome P450 2E1 can be induced by long-term exposure to ethanol in cultured liver HEP-G2 cells.

    Science.gov (United States)

    Balusikova, Kamila; Kovar, Jan

    2013-09-01

    It has been shown in previous studies that liver HEP-G2 cells (human hepatocellular carcinoma) lose their ability to express active alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1). Although both are ethanol-inducible enzymes, short-term exposure to ethanol does not cause any changes in expression or activity in cultured HEP-G2 cells. Therefore, we tested the effect of long-term exposure to ethanol on the expression and activity of both ADH and CYP2E1 in these cells. The expression of ADH and CYP2E1 was assessed at the mRNA and/or protein level using real-time PCR and Western blot analysis. Specific colorimetric assays were used for the measurement of ADH and CYP2E1 enzymatic activities. Caco-2 cells (active CYP2E1 and inactive ADH) were used as control cells. Significantly increased protein expression of ADH (about 2.5-fold) as well as CYP2E1 (about 1.6-fold) was found in HEP-G2 cells after long-term (12 mo) exposure to ethanol. The activity of ADH and CYP2E1 was also significantly increased from 12 ± 3 and 6 ± 1 nmol/h/mg of total protein to 191 ± 9 and 57 ± 9 nmol/h/mg of total protein, respectively. We suggest that the loss of activity of ethanol-metabolizing enzymes in cultured HEP-G2 cells is reversible and can be induced by prolonged exposure to ethanol. We are therefore able to reactivate HEP-G2 cells metabolic functions concerning ethanol oxidation just by modification of in vitro culture conditions without necessity of transfection with its side effect - enzyme overexpression.

  1. The long-term effects of methamphetamine exposure during pre-adolescence on depressive-like behaviour in a genetic animal model of depression.

    Science.gov (United States)

    Mouton, Moné; Harvey, Brian H; Cockeran, Marike; Brink, Christiaan B

    2016-02-01

    Methamphetamine (METH) is a psychostimulant and drug of abuse, commonly used early in life, including in childhood and adolescence. Adverse effects include psychosis, anxiety and mood disorders, as well as increased risk of developing a mental disorder later in life. The current study investigated the long-term effects of chronic METH exposure during pre-adolescence in stress-sensitive Flinders Sensitive Line (FSL) rats (genetic model of depression) and control Flinders Resistant Line (FRL) rats. METH or vehicle control was administered twice daily from post-natal day 19 (PostND19) to PostND34, followed by behavioural testing at either PostND35 (early effects) or long-lasting after withdrawal at PostND60 (early adulthood). Animals were evaluated for depressive-like behaviour, locomotor activity, social interaction and object recognition memory. METH reduced depressive-like behaviour in both FSL and FRL rats at PostND35, but enhanced this behaviour at PostND60. METH also reduced locomotor activity on PostND35 in both FSL and FRL rats, but without effect at PostND60. Furthermore, METH significantly lowered social interaction behaviour (staying together) in both FRL and FSL rats at PostND35 and PostND60, whereas self-grooming time was significantly reduced only at PostND35. METH treatment enhanced exploration of the familiar vs. novel object in the novel object recognition test (nORT) in FSL and FRL rats on PostND35 and PostND60, indicative of reduced cognitive performance. Thus, early-life METH exposure induce social and cognitive deficits. Lastly, early-life exposure to METH may result in acute antidepressant-like effects immediately after chronic exposure, whereas long-term effects after withdrawal are depressogenic. Data also supports a role for genetic predisposition as with FSL rats.

  2. Association of long-term exposure to community noise and traffic-related air pollution with coronary heart disease mortality.

    Science.gov (United States)

    Gan, Wen Qi; Davies, Hugh W; Koehoorn, Mieke; Brauer, Michael

    2012-05-01

    In metropolitan areas, road traffic is a major contributor to ambient air pollution and the dominant source of community noise. The authors investigated the independent and joint influences of community noise and traffic-related air pollution on risk of coronary heart disease (CHD) mortality in a population-based cohort study with a 5-year exposure period (January 1994-December 1998) and a 4-year follow-up period (January 1999-December 2002). Individuals who were 45-85 years of age and resided in metropolitan Vancouver, Canada, during the exposure period and did not have known CHD at baseline were included (n = 445,868). Individual exposures to community noise and traffic-related air pollutants, including black carbon, particulate matter less than or equal to 2.5 μm in aerodynamic diameter, nitrogen dioxide, and nitric oxide, were estimated at each person's residence using a noise prediction model and land-use regression models, respectively. CHD deaths were identified from the provincial death registration database. After adjustment for potential confounders, including traffic-related air pollutants or noise, elevations in noise and black carbon equal to the interquartile ranges were associated with 6% (95% confidence interval: 1, 11) and 4% (95% confidence interval: 1, 8) increases, respectively, in CHD mortality. Subjects in the highest noise decile had a 22% (95% confidence interval: 4, 43) increase in CHD mortality compared with persons in the lowest decile. These findings suggest that there are independent effects of traffic-related noise and air pollution on CHD mortality.

  3. Brief predator sound exposure elicits behavioral and neuronal long-term sensitization in the olfactory system of an insect

    DEFF Research Database (Denmark)

    Anton, S.; Evengaard, K.; Barrozo, R. B.

    2011-01-01

    these processes have been described. However, the influence of sensory signals on the sensitivity of a different modality is largely unknown. In males of the noctuid moth, Spodoptera littoralis, the sensitivity to the female-produced sex pheromone increases 24 h after a brief preexposure with pheromone...... at the behavioral and central nervous level. Here we show that this effect is not confined to the same sensory modality: the sensitivity of olfactory neurons can also be modulated by exposure to a different sensory stimulus, i.e., a pulsed stimulus mimicking echolocating sounds from attacking insectivorous bats. We......, but also on the central nervous level, in an insect....

  4. Effect of exposure conditions on the long-term dielectric properties of mortar samples containing ASR gel

    Science.gov (United States)

    Hashemi, A.; Donnell, K. M.; Zoughi, R.; Rashidi, M.; Kurtis, K. E.

    2017-02-01

    Alkali-silica reaction (ASR) is a chemical reaction between alkalis present in portland cement and amorphous or otherwise disordered siliceous minerals in particular aggregates. Through this reaction, reactive silica binds with hydroxyl and alkali ions and forms a gel, known as ASR gel. Recently, microwave materials characterization techniques have shown great potential for detecting ASR in mortar. However, the comprehensive understanding of variables that affect the extent of ASR in mortar and their interaction with microwave signals, in particular the effect of environmental exposure conditions requires more investigations. Therefore, parameters related to these conditions must be considered when using microwave techniques for ASR detection and evaluation. In this paper, the effect of exposure conditions on ASR gel formation and microwave dielectric properties of mortar samples is investigated. To this end, extended measurements of the complex dielectric constants of three different sets of mortar samples are presented at S-band (2.6 - 3.95 GHz). The samples were cast with potentially reactive ASR-aggregates and subjected to different environmental conditions. The results show slightly different permittivities for the differently stored samples, potentially indicating different amount of ASR gel. This observation was corroborated through UV fluorescence microscopy, where different amounts of ASR gel were observed in the samples. Moreover, the results indicate that ASR gel evolution may be better tracked through loss factor measurements, while pre-existing-gel may be better detected through permittivity measurements.

  5. [Exposure to CT scans in childhood and long-term cancer risk: A review of epidemiological studies].

    Science.gov (United States)

    Baysson, Hélène; Journy, Neige; Roué, Tristan; Ducou-Lepointe, Hubert; Etard, Cécile; Bernier, Marie-Odile

    2016-02-01

    Amongst medical exams requiring ionizing radiation, computed tomography (CT) scans are used more frequently, including in children. These CT examinations are associated with absorbed doses that are much higher than those associated with conventional radiology. In comparison to adults, children have a greater sensitivity to radiation and a longer life span with more years at cancer risks. Five epidemiological studies on cancer risks after CT scan exposure during childhood were published between 2012 and 2015. The results of these studies are consistent and show an increase of cancer risks in children who have been exposed to several CT scans. However, methodological limits due to indication bias, retrospective assessment of radiation exposure from CT scans and lack of statistical power are to be taken into consideration. International projects such as EPI-CT (Epidemiological study to quantify risks for pediatric computerized tomography and to optimize dose), with a focus on dosimetric reconstruction and minimization of bias will provide more precise results. In the meantime, available results reinforce the necessity of justification and optimization of doses.

  6. Antioxidant biochemical responses to long-term copper exposure in Bathymodiolus azoricus from Menez-Gwen hydrothermal vent.

    Science.gov (United States)

    Company, Rui; Serafim, Angela; Cosson, Richard P; Fiala-Médioni, Aline; Camus, Lionel; Colaço, Ana; Serrão-Santos, Ricardo; Bebianno, Maria João

    2008-01-25

    Copper (Cu) is essential to various physiological processes in marine organisms. However, at high concentrations this redox-active transition metal may enhance the formation of reactive oxygen species (ROS) and subsequently initiate oxidative damage. High concentrations of Cu may increase oxidative damage to lipids, proteins and DNA. Bathymodiolus azoricus is a Mytilid bivalve very common in hydrothermal environments near the Azores Triple Junction continuously exposed to high metal concentrations, including Cu, emanating from the vent fluids. The knowledge of antioxidant defence system and other stress related biomarkers in these organisms is still scarce. The aim of this work was to study the effect of Cu (25 microg l(-1); 24 days exposure; 6 days depuration) on the antioxidant stress biomarkers in the gills and mantle of B. azoricus. The expression of stress related biomarkers was tissue-dependent and results suggest that other factors than metal exposure may influence stress biomarkers, since little variation in antioxidant enzymes activities, MT concentrations, LPO and total oxyradical scavenging capacity (TOSC) occurred in both control and Cu-exposed mussels. Moreover, there is a general tendency for these parameters to increase with time, in both control and Cu-exposed mussels, suggesting that reactive oxygen species (ROS) formation is not metal dependent, and may be related with poor physiological conditions of the animals after long periods in adverse conditions compared to those in hydrothermal environments.

  7. Metal bioaccumulation and mutagenesis in a Tradescantia clone following long-term exposure to soils from urban industrial areas and closed landfills.

    Science.gov (United States)

    Čėsnienė, Tatjana; Kleizaitė, Violeta; Bondzinskaitė, Skaistė; Taraškevičius, Ričardas; Žvingila, Donatas; Šiukšta, Raimondas; Rančelis, Vytautas

    2017-11-01

    Soil mutagens, particularly metals, may persist long after the source of pollution has been removed, representing a hazard to plants, animals, and humans in or near contaminated areas. Often, due to urban growth, previous land uses may be forgotten and hazards overlooked. We exposed Tradescantia clone #4430 plants to soil from two industrial areas (with different former uses) and two urban waste landfills in the city of Vilnius, all of which were long disused. Two modes of exposure were used: long-term exposure of growing plants in test soils for 0.5 or 1.0y, and short-term exposure of cuttings to water and dimethyl sulfoxide (DMSO) soil extracts. An increased frequency of micronuclei (MN) was observed with both modes of exposure. The concentrations of 24 metals and other elements were analyzed in the test soils and in above-ground plant parts, under both exposure modes, and the concentration coefficients (Cc) for various elements, the total contamination index (Zs) for soils and plants, and the bioaccumulation factor (BAF) for plants were calculated. These measurements allow a comparison of the contamination levels of soils and plants with equalized values. Metal accumulation levels in plants and soils showed significant differences, providing a better understanding of the genotoxicity of soils from closed landfills and highlighting the need to determine the concentrations of metals and other genotoxicants in plants in relation to genotoxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Long-term behavioral change as a result of acute ethanol exposure in zebrafish: Evidence for a role for sonic hedgehog but not retinoic acid signaling.

    Science.gov (United States)

    Burton, Derek F; Zhang, Chengjin; Boa-Amponsem, Oswald; Mackinnon, Shanta; Cole, Gregory J

    2017-05-01

    Developmental exposure to ethanol is recognized to produce long-term neurobehavioral impairment in multiple animal models. However, the molecular mechanisms underlying these deficits remain poorly understood. The present study was undertaken to ascertain whether two well-characterized targets of prenatal alcohol exposure, sonic hedgehog (Shh) and retinoic acid (RA), that induce the hallmark morphological phenotypes of fetal alcohol spectrum disorders (FASD), are involved in the generation of behavioral alterations as a result of alcohol exposure. Zebrafish embryos were exposed to ethanol (0%, 1%, 3%) at either 8-10 or 24-27h post-fertilization (hpf) and then evaluated during adolescence in the novel tank dive test to assess anxiety and risk-taking behavior. Overt signs of dysmorphogenesis were also scored and behavioral and morphological changes were compared for embryos treated with alcohol alone or in combination with subthreshold doses of shh or alhh1a3 morpholinos (MOs). Ethanol treated fish displayed altered tank diving behavior that was not exacerbated by combined MO treatment. While treatment of embryos with either shha mRNA or RA prior to ethanol exposure only ameliorated the altered tank diving response in the case of shha mRNA overexpression, dysmorphogenesis was rescued by both treatments. These results suggest that the effects of ethanol exposure on changes in anxiety and risk-taking behavior in adolescent zebrafish is manifested by a blunting of Shh, but not RA, signaling during early development. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Long-term exposure to ambient air pollution and incidence of brain tumours: The Danish Nurse Cohort

    DEFF Research Database (Denmark)

    Jørgensen, Jeanette Therming; Johansen, Martin Søes; Ravnskjær, Line

    2016-01-01

    -reported information on lifestyle was collected. We obtained data on the incidence of brain tumours until 2013 from the Danish Cancer Register, and estimated annual mean concentrations of particulate matter with diameter... by location (brain or meninges), and by malignancy (malignant or benign), and estimated hazard ratios and 95% confidence intervals per increase in interquartile range of exposure. RESULTS: Of 25,143 tumour-free nurses at recruitment, 121 developed brain cancer during 15.7 years of follow-up. We found a weak......BACKGROUND: Air pollution has been considered a potent environmental risk factor for neuropathology through neuroinflammation and oxidative stress, which might also cause brain tumour formation. However, epidemiological evidence on the association between air pollution and brain tumours in humans...

  10. The long-term impact of the MEMA kwa Vijana adolescent sexual and reproductive health intervention: effect of dose and time since intervention exposure.

    Directory of Open Access Journals (Sweden)

    Aoife M Doyle

    Full Text Available BACKGROUND: Despite recent decreases in HIV incidence in many sub-Saharan African countries, there is little evidence that specific behavioural interventions have led to a reduction in HIV among young people. Further and wider-scale decreases in HIV require better understanding of when behaviour change occurs and why. The MEMA kwa Vijana adolescent sexual and reproductive health intervention has been implemented in rural Mwanza, Tanzania since 1999. A long-term evaluation in 2007/8 found that the intervention improved knowledge, attitudes to sex and some reported risk behaviours, but not HIV or HSV2 prevalence. The aim of this paper was to assess the differential impact of the intervention according to gender, age, marital status, number of years of exposure and time since last exposure to the intervention. METHODS: In 2007, a cross-sectional survey was conducted in the 20 trial communities among 13,814 young people (15-30 yrs who had attended intervention or comparison schools between 1999 and 2002. Outcomes for which the intervention had an impact in 2001 or 2007 were included in this subgroup analysis. Data were analysed using cluster-level methods for stratified cluster-randomised trials, using interaction tests to determine if intervention impact differed by subgroup. RESULTS: Taking into account multiplicity of testing, concurrence with a priori hypotheses and consistency within the results no strong effect-modifiers emerged. Impact on pregnancy knowledge and reported attitudes to sex increased with years of exposure to high-quality intervention. CONCLUSIONS: The desirable long-term impact of the MEMA kwa Vijana intervention did not vary greatly according to the subgroups examined. This suggests that the intervention can have an impact on a broad cross-section of young people in rural Mwanza. TRIAL REGISTRATION: ClinicalTrials.gov NCT00248469.

  11. Biomonitoring short- and long-term exposure to the herbicide terbuthylazine in agriculture workers and in the general population using urine and hair specimens.

    Science.gov (United States)

    Mercadante, Rosa; Polledri, Elisa; Bertazzi, Pier Alberto; Fustinoni, Silvia

    2013-10-01

    The aim of this work was to evaluate short-term and long-term exposure to terbuthylazine (TBA) in agriculture workers (AW), rural residents (RR), and urban residents (UR) using urine and hair specimens. Twelve AW, 13 RR, and 17 UR were included in the study. Urine spot samples were collected with two different protocols. AW urine samples were collected before the application season (February, U0), at bedtime on the day of TBA application (March-May, U1), and prior to the next shift on the day after TBA application (U2). RR and UR urine samples were collected on any day during the application season (Ue). Hair samples were collected for all subjects before the application season (February, H0) and at the end of the season (June, H1). TBA and its metabolite desethylterbuthylazine (DET) were measured by liquid chromatography coupled with triple quadrupole mass spectrometry detection. DET was exclusively found in urine, while TBA was mostly found in the hair. In the AW, the urinary levels of DET were not detected in the U0 samples, and they increased to median levels of 1.81 and 2.94μg/L in the U1 and U2 samples, respectively (p<0.001). In the RR and UR, DET was not detected in the Ue samples. In the UR, TBA was not detected in the H0 samples, and the median levels of TBA were 0.01ng/mg hair in both the AW and RR. In the H1 samples, the median TBA levels were not detected, 0.01, and 0.08ng/mg hair in the UR, RR, and AW, respectively (p<0.001). Urinary DET and hair TBA are promising candidates for biomonitoring short- and long-term exposure to TBA. The use of this herbicide in agriculture leads to exposure in rural residents.

  12. Long-term genomic and epigenomic dysregulation as a consequence of prenatal alcohol exposure: a model for fetal alcohol spectrum disorders

    Directory of Open Access Journals (Sweden)

    Morgan L Kleiber

    2014-06-01

    Full Text Available There is abundant evidence that prenatal alcohol exposure leads to a range of behavioural and cognitive impairments, categorized under the term fetal alcohol spectrum disorders (FASDs. These disorders are pervasive in Western cultures and represent the most common preventable source of neurodevelopmental disabilities. The genetic and epigenetic etiology of these phenotypes, including those factors that may maintain these phenotypes throughout the lifetime of an affected individual, has become a recent topic of investigation. This review integrates recent data that has progressed our understanding FASD as a continuum of molecular events, beginning with cellular stress response and ending with a long-term ‘footprint’ of epigenetic dysregulation across the genome. It reports on data from multiple ethanol-treatment paradigms in mouse models that identify changes in gene expression that occur with respect to neurodevelopmental timing of exposure and ethanol dose. These studies have identified patterns of genomic alteration that are dependent on the biological processes occurring at the time of ethanol exposure. This review also adds to evidence that epigenetic processes such as DNA methylation, histone modifications, and non-coding RNA regulation may underlie long-term changes to gene expression patterns. These may be initiated by ethanol-induced alterations to DNA and histone methylation, particularly in imprinted regions of the genome, affecting transcription which is further fine-tuned by altered microRNA expression. These processes are likely complex, genome-wide, and interrelated. The proposed model suggests a potential for intervention, given that epigenetic changes are malleable and may be altered by postnatal environment. This review accentuates the value of mouse models in deciphering the molecular etiology of FASD, including those processes that may provide a target for the ammelioration of this common yet entirely preventable disorder.

  13. Maintenance of C sinks sustains enhanced C assimilation during long-term exposure to elevated [CO2] in Mojave Desert shrubs.

    Science.gov (United States)

    Aranjuelo, Iker; Ebbets, Allison L; Evans, R Dave; Tissue, David T; Nogués, Salvador; van Gestel, Natasja; Payton, Paxton; Ebbert, Volker; Adams, Williams W; Nowak, Robert S; Smith, Stanley D

    2011-10-01

    During the first few years of elevated atmospheric [CO(2)] treatment at the Nevada Desert FACE Facility, photosynthetic downregulation was observed in desert shrubs grown under elevated [CO(2)], especially under relatively wet environmental conditions. Nonetheless, those plants maintained increased A (sat) (photosynthetic performance at saturating light and treatment [CO(2)]) under wet conditions, but to a much lesser extent under dry conditions. To determine if plants continued to downregulate during long-term exposure to elevated [CO(2)], responses of photosynthesis to elevated [CO(2)] were examined in two dominant Mojave Desert shrubs, the evergreen Larrea tridentata and the drought-deciduous Ambrosia dumosa, during the eighth full growing season of elevated [CO(2)] treatment at the NDFF. A comprehensive suite of physiological processes were collected. Furthermore, we used C labeling of air to assess carbon allocation and partitioning as measures of C sink activity. Results show that elevated [CO(2)] enhanced photosynthetic performance and plant water status in Larrea, especially during periods of environmental stress, but not in Ambrosia. δ(13)C analyses indicate that Larrea under elevated [CO(2)] allocated a greater proportion of newly assimilated C to C sinks than Ambrosia. Maintenance by Larrea of C sinks during the dry season partially explained the reduced [CO(2)] effect on leaf carbohydrate content during summer, which in turn lessened carbohydrate build-up and feedback inhibition of photosynthesis. δ(13)C results also showed that in a year when plant growth reached the highest rates in 5 years, 4% (Larrea) and 7% (Ambrosia) of C in newly emerging organs were remobilized from C that was assimilated and stored for at least 2 years prior to the current study. Thus, after 8 years of continuous exposure to elevated [CO(2)], both desert perennials maintained their photosynthetic capacities under elevated [CO(2)]. We conclude that C storage, remobilization

  14. Effects of Long Term Exposure of 900-1800 MHz Radiation Emitted from 2G Mobile Phone on Mice Hippocampus- A Histomorphometric Study

    Science.gov (United States)

    Shanmugasamy, Kathirvelu; Anbalagan, Jayaram; Rajanarayanan, Swamynathan; Meenachi, Swamynathan

    2016-01-01

    Introduction The advancement in the telecommunications technology with multi-functional added features in mobile phone, attracts more users of all age group. It is alarming to note that, the mobile phone use has increased amongst children and they are exposed to potentially harmful radiofrequency radiation in their lifetime. Aim To investigate the long term exposure of 900 to 1800 MHz radiations emitted from 2G mobile phone in mice hippocampus at histomorphometric level. Materials and Methods With due approval from institutional animal ethics committee, 36 mice were exposed to 2G mobile phone radiation, 48 minutes per day for a period of 30-180 days. The control group was kept under similar conditions without 2G exposure. Mice were sacrificed and the brain was removed from the first month to six months period. Brain was removed from the cranial cavity and hippocampus region was dissected out carefully and processed for routine histological study. Random serial sections were analysed under microscope for histomorphometric changes. For statistical analysis, independent t-test was used for comparing control and 2G exposed groups. Results The mean density of neurons in the hippocampus regions CA1, CA2 and DGDB from first to sixth month was significantly lower in the 2G exposed groups; however, in CA3 and DGVB, the 2G exposed mice showed significantly higher density of neurons. The mean nuclear diameter of neurons in the hippocampus region of CA1, CA2, CA3, DGDB and DGVB from first to sixth months showed lower nuclear diameter in 2G exposed mice. Conclusion The long term exposure to 900-1800 MHz frequency radiations emitted from 2G mobile phone could cause significantly reduced neuron density and decreased nuclear diameter in the hippocampus neurons of mice. PMID:27656427

  15. Effects of Long-term exposure of Gelatinated and Non-gelatinated Cadmium Telluride Quantum Dots on Differentiated PC12 cells

    LENUS (Irish Health Repository)

    Prasad, Babu R

    2012-01-20

    Abstract Background The inherent toxicity of unmodified Quantum Dots (QDs) is a major hindrance to their use in biological applications. To make them more potent as neuroprosthetic and neurotherapeutic agents, thioglycolic acid (TGA) capped CdTe QDs, were coated with a gelatine layer and investigated in this study with differentiated pheochromocytoma 12 (PC12) cells. The QD - cell interactions were investigated after incubation periods of up to 17 days by MTT and APOTOX-Glo Triplex assays along with using confocal microscopy. Results Long term exposure (up to 17 days) to gelatinated TGA-capped CdTe QDs of PC12 cells in the course of differentiation and after neurites were grown resulted in dramatically reduced cytotoxicity compared to non-gelatinated TGA-capped CdTe QDs. Conclusion The toxicity mechanism of QDs was identified as caspase-mediated apoptosis as a result of cadmium leaking from the core of QDs. It was therefore concluded that the gelatine capping on the surface of QDs acts as a barrier towards the leaking of toxic ions from the core QDs in the long term (up to 17 days).

  16. Emiliania huxleyi increases calcification but not expression of calcification-related genes in long-term exposure to elevated temperature and pCO2.

    Science.gov (United States)

    Benner, Ina; Diner, Rachel E; Lefebvre, Stephane C; Li, Dian; Komada, Tomoko; Carpenter, Edward J; Stillman, Jonathon H

    2013-01-01

    Increased atmospheric pCO2 is expected to render future oceans warmer and more acidic than they are at present. Calcifying organisms such as coccolithophores that fix and export carbon into the deep sea provide feedbacks to increasing atmospheric pCO2. Acclimation experiments suggest negative effects of warming and acidification on coccolithophore calcification, but the ability of these organisms to adapt to future environmental conditions is not well understood. Here, we tested the combined effect of pCO2 and temperature on the coccolithophore Emiliania huxleyi over more than 700 generations. Cells increased inorganic carbon content and calcification rate under warm and acidified conditions compared with ambient conditions, whereas organic carbon content and primary production did not show any change. In contrast to findings from short-term experiments, our results suggest that long-term acclimation or adaptation could change, or even reverse, negative calcification responses in E. huxleyi and its feedback to the global carbon cycle. Genome-wide profiles of gene expression using RNA-seq revealed that genes thought to be essential for calcification are not those that are most strongly differentially expressed under long-term exposure to future ocean conditions. Rather, differentially expressed genes observed here represent new targets to study responses to ocean acidification and warming.

  17. Effects of long-term exposure of gelatinated and non-gelatinated cadmium telluride quantum dots on differentiated PC12 cells

    Directory of Open Access Journals (Sweden)

    Prasad Babu R

    2012-01-01

    Full Text Available Abstract Background The inherent toxicity of unmodified Quantum Dots (QDs is a major hindrance to their use in biological applications. To make them more potent as neuroprosthetic and neurotherapeutic agents, thioglycolic acid (TGA capped CdTe QDs, were coated with a gelatine layer and investigated in this study with differentiated pheochromocytoma 12 (PC12 cells. The QD - cell interactions were investigated after incubation periods of up to 17 days by MTT and APOTOX-Glo Triplex assays along with using confocal microscopy. Results Long term exposure (up to 17 days to gelatinated TGA-capped CdTe QDs of PC12 cells in the course of differentiation and after neurites were grown resulted in dramatically reduced cytotoxicity compared to non-gelatinated TGA-capped CdTe QDs. Conclusion The toxicity mechanism of QDs was identified as caspase-mediated apoptosis as a result of cadmium leaking from the core of QDs. It was therefore concluded that the gelatine capping on the surface of QDs acts as a barrier towards the leaking of toxic ions from the core QDs in the long term (up to 17 days.

  18. Effects of long-term exposure to ammonium sulfate particles on growth and gas exchange rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica seedlings

    Science.gov (United States)

    Yamaguchi, Masahiro; Otani, Yoko; Li, Peiran; Nagao, Hiroshi; Lenggoro, I. Wuled; Ishida, Atsushi; Yazaki, Kenichi; Noguchi, Kyotaro; Nakaba, Satoshi; Yamane, Kenichi; Kuroda, Katsushi; Sano, Yuzou; Funada, Ryo; Izuta, Takeshi

    2014-11-01

    To clarify the effects of long-term exposure to ammonium sulfate (AS) particles on growth and physiological functions of forest tree species, seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron-size AS particles during two growing seasons from 3 June 2011 to 8 October 2012. The mean sulfate concentration in PM2.5 increased during the exposure inside the chamber in 2011 and 2012 by 2.73 and 4.32 μg SO42- m-3, respectively. No significant effects of exposure to AS particles were detected on the whole-plant dry mass of the seedlings. These results indicate that the exposure to submicrometer AS particles at the ambient level for two growing seasons did not significantly affect the growth of the seedlings. No significant effects of exposure to AS particles were found on the net photosynthetic rate in the leaves or needles of F. crenata, C. sieboldii and L. kaempferi seedlings. Also, in the previous-year needles of C. japonica seedlings, exposure to AS particles significantly reduced the net photosynthetic rate, which may be caused by the reduction in the concentration of ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco). On the contrary, in current-year needles of C. japonica seedlings, net photosynthetic rate significantly increased with exposure to AS particles, which may be the result of increases in stomatal conductance and concentrations of Rubisco and chlorophyll. Furthermore, exposure to AS particles correlated with an increase in concentrations of NH4+, free amino acid and total soluble protein, suggesting that AS particles may be deliquesced, absorbed into the leaves and metabolized into amino acid and protein. These results suggest that net photosynthesis in the needles of C. japonica is relatively sensitive to submicron-size AS particles as compared with the other three tree species.

  19. Ultrastructure of the gut epithelium in Acheta domesticus after long-term exposure to nanodiamonds supplied with food.

    Science.gov (United States)

    Karpeta-Kaczmarek, Julia; Augustyniak, Maria; Rost-Roszkowska, Magdalena

    2016-05-01

    The biosafety of nanoparticles and the potential toxicity of nanopollutants and/or nanowastes are all currently burning issues. The increased use of nanoparticles, including nanodiamonds (ND), entails the real risk of their penetration into food chains, which may result in the contamination of animal and, as a result, human food. Knowledge about changes in the ultrastructure of tissues in organisms that have been exposed to ND is still very limited. The aim of the study was to describe the ultrastructure of the gut epithelium in Acheta domesticus after exposure to different concentrations of ND (0, 20 or 200 μg g(-1) - control, ND20 and ND200 groups, respectively) administered with food over a five-week period. The ultrastructure of the foregut, midgut and hindgut was assessed using Transmission Electron Microscopy (TEM). A number of changes in the structure of the gut in crickets that had consumed nanodiamond-contaminated food were observed. The epithelium of the midgut and hindgut were clearly damaged by ND, although the foregut was not affected. A positive relationship between the ND concentration in food and the degree of damage to the structure of epithelial cells was observed. Autophagy, especially mitophagy and reticulophagy, was activated in relation to the appearance of ND particles. A putative ND toxicity mechanizm is proposed. Extreme caution should be maintained when using nanodiamonds on a large scale.

  20. Long-term alterations of striatal parvalbumin interneurons in a rat model of early exposure to alcohol

    Directory of Open Access Journals (Sweden)

    De Giorgio Andrea

    2012-07-01

    Full Text Available Abstract Background Exposure to alcohol in utero is a known cause of mental retardation. Although a certain degree of motor impairment is always associated with fetal alcohol spectrum disorder, little is known about the neurobiological basis of the defective motor control. We have studied the striatal interneurons containing parvalbumin in a rat model of fetal alcohol spectrum disorder. Methods Newborn rats received ethanol by inhalation from postnatal day two through six and parvalbumin striatal neurons were labeled by immunohistochemistry on postnatal day 60. The spatial distribution of parvalbumin interneurons was studied using Voronoi spatial tessellation and their dendritic trees were completely reconstructed. Results Parvalbumin interneurons of ethanol-treated animals showed a clustered spatial distribution similar to that observed in control animals. The dendritic tree of parvalbumin interneurons was significantly reduced in ethanol-treated animals, as compared with controls. Conclusions Striatal parvalbumin interneurons are crucial components of the brain network serving motor control. Therefore, the shrinkage of their dendrites could contribute to the motor and cognitive symptoms observed in fetal alcohol spectrum disorder.

  1. In Utero Exposure to Low Doses of Bisphenol A Lead to Long-term Deleterious Effects in the Vagina

    Directory of Open Access Journals (Sweden)

    G. Schönfelder

    2002-01-01

    Full Text Available The origins of the “endocrine disrupter hypothesis” may be traced to reports on adolescent daughters born to women who had taken the highly potent synthetic estrogen, diethylstilbestrol, while pregnant, and who developed a rare form of vaginal cancer and adenocarcinoma. Bisphenol A (BPA is an estrogenic chemical that is highly employed in the manufacture of a wide range of consumer products. Some observational studies have suggested that the amounts of BPA to which we are exposed could alter the reproductive organs of developing rodents. We examined the influence of BPA at low doses to address the questions of (a whether in utero exposure affects the vagina of the offspring and (b which mechanisms cause the toxic effects. Gravid Sprague-Dawley dams were administered either 0.1 (low dose or 50 mg/kg per day BPA, the no observed effect level, or 0.2 mg/kg per day 17αethinyl estradiol by gavage. Striking morphological changes were observed in the vagina of postpubertal offspring leading us to examine vaginal estrogen receptor (ER expression because BPA binds to the ERα, which is important for growth of the vaginal epithelium. We show that the full-length ERα is not expressed during estrus in the vagina of female offspring exposed to either dose of BPA when compared to the control group, whereas ERα expression does not differ from the control group during the diestrus stage. ERa downregulation seems to be responsible for the observed altered vaginal morphology.

  2. Effect of Vitamin E Supplementation on Hematological and Plasma Biochemical Parameters during Long Term Exposure of Arsenic in Goats

    Directory of Open Access Journals (Sweden)

    Tapan Kumar Das

    2012-09-01

    Full Text Available The present investigation was designed to determine whether supplementation of different level of vitamin E for 12 months to arsenic exposed goats (50 ppm as sodium arsenite affords protection against the blood hemato-biochemical parameters caused by the metalloid. A total of 24 crossbred (Alpine×Beetal lactating goats were assigned randomly into 4 equal groups (control, T1, T2 and T3 of 6 in each, on the basis of average body weight (36.10±0.11 kg and milk yield (1.61±0.04 kg/d. The animals in T1, T2 and T3 were given 50 ppm arsenic, while in T2 and T3, additionally; vitamin E at the rate of 100 IU and 150 IU/kg dry matter (DM respectively was additionally supplemented for the period of 12 months. Hemoglobin (Hb, total leukocyte (TLC and blood lymphocyte % were decreased (p0.05 but creatinine level was periodically increased in all As supplemented groups and vitamin E supplementation did not produce any protective effect. It can be concluded that arsenic exposure resulted in varying degree of changes in hemato-biochemical parameters and activities of antioxidant enzymes in goats but concomitant treatment with Vitamin E is partially helpful in reducing the burden of arsenic induced effect.

  3. Long-term exposure to paraquat alters behavioral parameters and dopamine levels in adult zebrafish (Danio rerio).

    Science.gov (United States)

    Bortolotto, Josiane W; Cognato, Giana P; Christoff, Raissa R; Roesler, Laura N; Leite, Carlos E; Kist, Luiza W; Bogo, Mauricio R; Vianna, Monica R; Bonan, Carla D

    2014-04-01

    Chronic exposure to paraquat (Pq), a toxic herbicide, can result in Parkinsonian symptoms. This study evaluated the effect of the systemic administration of Pq on locomotion, learning and memory, social interaction, tyrosine hydroxylase (TH) expression, dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels, and dopamine transporter (DAT) gene expression in zebrafish. Adult zebrafish received an i.p. injection of either 10 mg/kg (Pq10) or 20 mg/kg (Pq20) of Pq every 3 days for a total of six injections. Locomotion and distance traveled decreased at 24 h after each injection in both treatment doses. In addition, both Pq10- and Pq20-treated animals exhibited differential effects on the absolute turn angle. Nonmotor behaviors were also evaluated, and no changes were observed in anxiety-related behaviors or social interactions in Pq-treated zebrafish. However, Pq-treated animals demonstrated impaired acquisition and consolidation of spatial memory in the Y-maze task. Interestingly, dopamine levels increased while DOPAC levels decreased in the zebrafish brain after both treatments. However, DAT expression decreased in the Pq10-treated group, and there was no change in the Pq20-treated group. The amount of TH protein showed no significant difference in the treated group. Our study establishes a new model to study Parkinson-associated symptoms in zebrafish that have been chronically treated with Pq.

  4. Long-term collections

    CERN Multimedia

    Collectes à long terme

    2007-01-01

    The Committee of the Long Term Collections (CLT) asks for your attention for the following message from a young Peruvian scientist, following the earthquake which devastated part of her country a month ago.

  5. Effect of Vitamin E Supplementation on Hematological and Plasma Biochemical Parameters during Long Term Exposure of Arsenic in Goats.

    Science.gov (United States)

    Das, Tapan Kumar; Mani, Veena; Kaur, Harjit; Kewalramani, Neelam; Agarwal, Anjali

    2012-09-01

    The present investigation was designed to determine whether supplementation of different level of vitamin E for 12 months to arsenic exposed goats (50 ppm as sodium arsenite) affords protection against the blood hemato-biochemical parameters caused by the metalloid. A total of 24 crossbred (Alpine×Beetal) lactating goats were assigned randomly into 4 equal groups (control, T1, T2 and T3) of 6 in each, on the basis of average body weight (36.10±0.11 kg) and milk yield (1.61±0.04 kg/d). The animals in T1, T2 and T3 were given 50 ppm arsenic, while in T2 and T3, additionally; vitamin E at the rate of 100 IU and 150 IU/kg dry matter (DM) respectively was additionally supplemented for the period of 12 months. Hemoglobin (Hb), total leukocyte (TLC) and blood lymphocyte % were decreased (parsenic fed groups and vitamin E supplementation in the experimental group showed a protective potential. Significant increases (parsenic supplemented groups were recorded, however vitamin E supplementation at higher doses showed a protective effect (p0.05) but creatinine level was periodically increased in all As supplemented groups and vitamin E supplementation did not produce any protective effect. It can be concluded that arsenic exposure resulted in varying degree of changes in hemato-biochemical parameters and activities of antioxidant enzymes in goats but concomitant treatment with Vitamin E is partially helpful in reducing the burden of arsenic induced effect.

  6. Development and application of GC-MS method for monitoring of long-term exposure to the pesticide cypermethrin.

    Science.gov (United States)

    Kavvalakis, Matthaios P; Tzatzarakis, Manolis N; Alegakis, Athanasios K; Vynias, Dionysios; Tsakalof, Andreas K; Tsatsakis, Aristidis M

    2014-06-01

    Cypermethrin (CPMN) is a synthetic pyrethroid used as an insecticide in large-scale commercial agricultural applications as well as for domestic purposes. In the present study a gas chromatography-mass spectrometry (GC-MS) based method was developed and validated for the quantitation of CPMN metabolites, 3-phenoxybenzoic acid (3-PBA) and cis- and trans- 3-(2,2-dichlorovinyl)-2,2-dimethyl-1-cyclopropane (cis- and trans- Cl2 CA). The developed method was applied for the monitoring of CPMN metabolites in hair of laboratory animals (rabbits) intentionally exposed per os to CPMN at 40 (low dose) and 80 (high dose) mg/kg weight/day for 16 weeks. The analytical method comprises three main steps: isolation of analytes from hair, analytes derivatization, and subsequent instrumental analysis by GC-MS. The limits of detection ensured by the method are 4.0, 3.9 and 1.0 pg/mg hair for cis-Cl2 CA, trans-Cl2 CA and 3-PBA, respectively. The instrument responce is linear (r(2)  > 0.99) in the investigated concentrations range from 25 to 1000 pg/mg. With and between-run precision as well as accuracy were estimated and found satisfactory. Analytes were efficiently isolated by solid-liquid extraction from hair with recoveries greater than 84.8% for cis-Cl2 CA, 87.2% for trans-Cl2 CA and 96.4% for 3-PBA. Rabbit's hair showed increasing levels for all metabolites (metabolites accumulation in a time and dose dependent manner) over time and in a dose-dependent manner. The developed experimental procedure could be used for biomonitoring of population exposure to CPMN.

  7. Phytochelatin formation kinetics and toxic effects in the freshwater alga Chlamydomonas reinhardtii upon short- and long-term exposure to lead(II).

    Science.gov (United States)

    Scheidegger, Christian; Behra, Renata; Sigg, Laura

    2011-01-25

    Phytochelatins (PC) are metal-binding ligands synthesized by algae in response to elevated concentrations of various metals, such as Pb. Kinetics of PC synthesis and Pb accumulation in Chlamydomonas reinhardtii were investigated as a function of [Pb(2+)]=10(-11)-10(-7)M (pPb11-pPb7.1) in the exposure medium for up to 6h. The role of PC in Pb detoxification was explored by relating PC synthesis to the effects of Pb on growth and photosynthetic yield upon exposure to pPb9 and pPb8.3 for up to 72h. Pb accumulation increased with increasing [Pb(2+)], reaching a maximum concentration of 596±77amol/cell (intracellular concentration 2.98mM) at pPb7.1. Low concentrations of PC(2)-PC(4) were present in C. reinhardtii grown in control media without Pb addition. Upon short-term exposure, PC(2) and PC(3) synthesis was induced within minutes at [Pb(2+)]≥pPb8 and PC(4) synthesis after a lag phase at pPb7.1. Cellular PC(2)-PC(4) concentrations increased with time over 6h and with increasing [Pb(2+)]. PC concentrations after 6h exposure to pPb7.1 were 28.5±0.2amol/cell (142μM) PC(2), 2.8±0.05amol/cell (14μM) PC(3) and 0.30±0.01amol/cell (1.5μM) PC(4). Upon long-term exposure, induction of PC synthesis was detected at pPb9 and synthesis of PCs with a higher degree of polymerization was observed (PC(5)). PC concentrations were lower than intracellular Pb and were thus not present at sufficiently high concentrations to immobilize accumulated Pb. Inhibition of photosynthesis and growth up to 100% was observed upon long-term exposure, whereas in short-term experiments no inhibitory effects were detected.

  8. Utility and Cutoff Value of Hair Nicotine as a Biomarker of Long-Term Tobacco Smoke Exposure, Compared to Salivary Cotinine

    Directory of Open Access Journals (Sweden)

    Sungroul Kim

    2014-08-01

    Full Text Available While hair samples are easier to collect and less expensive to store and transport than biological fluids, and hair nicotine characterizes tobacco exposure over a longer time period than blood or urine cotinine, information on its utility, compared with salivary cotinine, is still limited. We conducted a cross-sectional study with 289 participants (107 active smokers, 105 passive smokers with self-reported secondhand smoke (SHS exposure, and 77 non-smokers with no SHS exposure in Baltimore (Maryland, USA. A subset of the study participants (n = 52 were followed longitudinally over a two-month interval.  Median baseline hair nicotine concentrations for active, passive and non-smokers were 16.2, 0.36, and 0.23 ng/mg, respectively, while those for salivary cotinine were 181.0, 0.27, and 0.27 ng/mL, respectively. Hair nicotine concentrations for 10% of passive or non-smokers were higher than the 25th percentile value for active smokers while all corresponding salivary cotinine concentrations for them were lower than the value for active smokers. This study showed that hair nicotine concentration values could be used to distinguish active or heavy passive adult smokers from non-SHS exposed non-smokers. Our results indicate that hair nicotine is a useful biomarker for the assessment of long-term exposure to tobacco smoke.

  9. Long-term valproic acid exposure increases the number of neocortical neurons in the developing rat brain. A possible new animal model of autism

    DEFF Research Database (Denmark)

    Sabers, Anne; Bertelsen, Freja C B; Scheel-Krüger, Jørgen

    2014-01-01

    The aim of this study was to test the hypothesis that long-term fetal valproic acid (VPA) exposure at doses relevant to the human clinic interferes with normal brain development. Pregnant rats were given intraperitoneal injections of VPA (20mg/kg or 100mg/kg) continuously during the last 9-12 days....../kg, but not to 20mg/kg VPA displayed a significant (pbrain development by disturbing neocortical organization, resulting in overgrowth of frontal lobes...... and increased neuronal cell numbers. The results indirectly suggest that prenatal VPA may contribute as a causative factor in the brain developmental disturbances equivalent to those seen in human autism spectrum disorders. We therefore suggest that this version of the VPA model may provide a translational...

  10. The Screening of Genes Sensitive to Long-Term, Low-Level Microwave Exposure and Bioinformatic Analysis of Potential Correlations to Learning and Memory

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ya Li; LI Ying Xian; MA Hong Bo; LI Dong; LI Hai Liang; JIANG Rui; KAN Guang Han; YANG Zhen Zhong; HUANG Zeng Xin

    2015-01-01

    Objective To gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfunction. Methods Mice were exposed to whole body 2100 MHz microwaves with specific absorption rates (SARs) of 0.45 W/kg, 1.8 W/kg, and 3.6 W/kg for 1 hour daily for 8 weeks. Differentially expressing genes in the brains were screened using high-density oligonucleotide arrays, with genes showing more significant differences further confirmed by RT-PCR. Results The gene chip results demonstrated that 41 genes (0.45 W/kg group), 29 genes (1.8 W/kg group), and 219 genes (3.6 W/kg group) were differentially expressed. GO analysis revealed that these differentially expressed genes were primarily involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, cellular component organization, etc. KEGG pathway analysis showed that these genes are mainly involved in pathways related to ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling. Construction of a protein interaction network identified several important regulatory genes including synbindin (sbdn), Crystallin (CryaB), PPP1CA, Ywhaq, Psap, Psmb1, Pcbp2, etc., which play important roles in the processes of learning and memory. Conclusion Long-term, low-level microwave exposure may inhibit learning and memory by affecting protein and energy metabolic processes and signaling pathways relating to neurological functions or diseases.

  11. Long-term prolactin exposure differentially stimulated the transcellular and solvent drag-induced calcium transport in the duodenum of ovariectomized rats.

    Science.gov (United States)

    Tudpor, Kukiat; Charoenphandhu, Narattaphol; Saengamnart, Wasana; Krishnamra, Nateetip

    2005-12-01

    Prolactin, having been shown to stimulate transcellular active and solvent drag-induced calcium transport in the duodenum of female rats, was postulated to improve duodenal calcium transport in estrogen-deficient rats. The aim of the present study was, therefore, to demonstrate the effects of long-term prolactin exposure produced by anterior pituitary (AP) transplantation on the duodenal calcium transport in young (9-week-old) and adult (22-week-old) ovariectomized rats. We found that ovariectomy did not alter the transcellular active duodenal calcium transport in young and adult rats fed normal calcium diet (1.0% w/w Ca) but decreased the solvent drag-induced duodenal calcium transport from 75.50 +/- 10.12 to 55.75 +/- 4.77 nmol.hr(-1).cm(-2) (P calcium transport in young and adult AP-grafted ovariectomized rats fed with normal calcium diet by more than 2-fold from 7.56 +/- 0.79 to 16.54 +/- 2.05 (P calcium transport in young rats was enhanced by prolactin from 95.51 +/- 10.64 to 163.20 +/- 18.03 nmol.hr(-1).cm(-2) (P calcium supplement has been widely used to improve calcium balance in estrogen-deficient animals, the effect of a high-calcium diet (2.0% w/w Ca) was also investigated. The results showed that stimulatory action of long-term prolactin on the transcellular active duodenal calcium transport in both young and adult rats was diminished after being fed a high-calcium diet. The same diet also abolished prolactin-enhanced solvent drag-induced duodenal calcium transport in young and further decreased that in adult AP-grafted ovariectomized rats. We concluded that the solvent drag-induced duodenal calcium transport in adult rats was decreased after ovariectomy. Long-term prolactin exposure stimulated the transcellular active duodenal calcium transport in both young and adult rats whereas enhancing the solvent drag-induced duodenal calcium transport only in young rats. Effects of prolactin were abolished by a high-calcium diet.

  12. Long-term changes in brain cholinergic system and behavior in rats following gestational exposure to lead: protective effect of calcium supplement

    Directory of Open Access Journals (Sweden)

    Basha Chand D.

    2015-12-01

    Full Text Available Our earlier studies showed that lactational exposure to lead (Pb caused irreversible neurochemical alterations in rats. The present study was carried out to examine whether gestational exposure to Pb can cause long-term changes in the brain cholinergic system and behavior of rats. The protective effect of calcium (Ca supplementation against Pb toxicity was also examined. Pregnant rats were exposed to 0.2% Pb (Pb acetate in drinking water from gestational day (GD 6 to GD 21. The results showed decrease in body weight gain (GD 6–21 of dams, whereas no changes were observed in offspring body weight at different postnatal days following Pb exposure. Male offspring treated with Pb showed marginal alterations in developmental landmarks such as unfolding of pinnae, lower and upper incisor eruption, fur development, eye slit formation and eye opening on postnatal day (PND 1, whereas significant alterations were found in the righting reflex (PNDs 4–7, slant board behavior (PNDs 8–10 and forelimb hang performance (PNDs 12–16. Biochemical analysis showed decrease in synaptosomal acetylcholinesterase (AChE activity and an increase in acetylcholine (ACh levels in the cortex, cerebellum and hippocampus on PND 14, PND 21, PND 28 and in the four-month age group of rats following Pb exposure. Significant deficits were also observed in total locomotor activity, exploratory behavior and open field behavior in selected age groups of Pb-exposed rats. These alterations were found to be maximal on PND 28, corresponding with the greater blood lead levels observed on PND 28. Addition of 0.02% Ca to Pb reversed the Pb-induced impairments in the cholinergic system as well as in behavioral parameters of rats. In conclusion, these data suggest that gestational exposure to Pb is able to induce long-term changes in neurological functions of offspring. Maternal Ca administration reversed these neurological effects of Pb later in life, suggesting a protective effect of

  13. Long-Term Exposure to Silica Dust and Risk of Total and Cause-Specific Mortality in Chinese Workers: A Cohort Study

    Science.gov (United States)

    Chen, Weihong; Liu, Yuewei; Wang, Haijiao; Hnizdo, Eva; Sun, Yi; Su, Liangping; Zhang, Xiaokang; Weng, Shaofan; Bochmann, Frank; Hearl, Frank J.; Chen, Jingqiong; Wu, Tangchun

    2012-01-01

    Background Human exposure to silica dust is very common in both working and living environments. However, the potential long-term health effects have not been well established across different exposure situations. Methods and Findings We studied 74,040 workers who worked at 29 metal mines and pottery factories in China for 1 y or more between January 1, 1960, and December 31, 1974, with follow-up until December 31, 2003 (median follow-up of 33 y). We estimated the cumulative silica dust exposure (CDE) for each worker by linking work history to a job–exposure matrix. We calculated standardized mortality ratios for underlying causes of death based on Chinese national mortality rates. Hazard ratios (HRs) for selected causes of death associated with CDE were estimated using the Cox proportional hazards model. The population attributable risks were estimated based on the prevalence of workers with silica dust exposure and HRs. The number of deaths attributable to silica dust exposure among Chinese workers was then calculated using the population attributable risk and the national mortality rate. We observed 19,516 deaths during 2,306,428 person-years of follow-up. Mortality from all causes was higher among workers exposed to silica dust than among non-exposed workers (993 versus 551 per 100,000 person-years). We observed significant positive exposure–response relationships between CDE (measured in milligrams/cubic meter–years, i.e., the sum of silica dust concentrations multiplied by the years of silica exposure) and mortality from all causes (HR 1.026, 95% confidence interval 1.023–1.029), respiratory diseases (1.069, 1.064–1.074), respiratory tuberculosis (1.065, 1.059–1.071), and cardiovascular disease (1.031, 1.025–1.036). Significantly elevated standardized mortality ratios were observed for all causes (1.06, 95% confidence interval 1.01–1.11), ischemic heart disease (1.65, 1.35–1.99), and pneumoconiosis (11.01, 7.67–14.95) among workers exposed

  14. Open reduction for congenital dislocation of the hip: comparison of the long-term results of the wide exposure method and Ludloff's method.

    Science.gov (United States)

    Matsushita, T; Miyake, Y; Akazawa, H; Eguchi, S; Takahashi, Y

    1999-01-01

    We compared the long-term clinical and radiographic results of two methods of open reduction for congenital dislocation of the hip; a wide exposure method (360-degree circumferential capsulotomy) versus Ludloff's method (limited capsulotomy via the medial approach). Thirty-one hips in 24 patients assigned to group A received the wide exposure method and 32 hips in 27 patients assigned to group B had the Ludloff reduction. All patients were surgically reduced at less than 3 years of age. The follow-up averaged 16 years. None of the hips in group A required additional operations; however, 34.4% of the hips in group B did. At the latest review, 26 (83.9%) of the hips in group A were rated as Severin class I or II. Except for one patient, none had pain or a limp. Of the hips in group B, 18 (56.3%) were rated as Severin class I or II. Three patients had pain or Trendelenburg gait. Avascular necrosis occurred in 3.2% of hips in group A and in 21.9% of hips in group B. The wide exposure method is capable of completely releasing the posterosuperior tightness resulting from capsular adhesion to the ilium and the contracted short external rotators. Releasing the posterosuperior tightness from these structures seemed to provide a better chance of achieving an anatomically and functionally satisfactory hip.

  15. Evaluation Effects of the Short- and Long-Term Freeze-Thaw Exposure on the Axial Behavior of Concrete-Filled Glass Fiber-Reinforced-Polymer Tubes

    Directory of Open Access Journals (Sweden)

    Hend El-Zefzafy

    2013-01-01

    Full Text Available Previous studies have demonstrated the high performance of the concrete-filled fiber-reinforced polymer (FRP tubes (CFFTs as a stay-in-place formwork and confining material for concrete structures. However, there are several concerns related to the behavior of CFFT as a protective jacket against harsh environmental effects. The environmental effects such as freeze-thaw cycles and deicing salt solutions may affect materials properties, which may affect the structural response of CFFT members as well. This paper presents the test results of experimental investigation on the durability of short- and long-term behaviors of CFFT members. Test variables included the effect of confining using GFRP tubes, freeze-thaw cycles exposure in salt water, and the number of freeze-thaw cycles. CFFT cylinders (150 × 300 mm were prepared and exposed to 100 and 300 freeze-thaw cycles in salt water condition. Then, pure axial compression tests were conducted in order to evaluate the performance of specimens due to freeze-thaw exposure, by comparing the stress-strain behavior and their ultimate load capacities. Test results indicated that the confinement using CFFT technique significantly protected the concrete when subjected to freeze-thaw exposure.

  16. The Fukushima nuclear accident and the pale grass blue butterfly: evaluating biological effects of long-term low-dose exposures.

    Science.gov (United States)

    Hiyama, Atsuki; Nohara, Chiyo; Taira, Wataru; Kinjo, Seira; Iwata, Masaki; Otaki, Joji M

    2013-08-12

    On August 9th 2012, we published an original research article in Scientific Reports, concluding that artificial radionuclides released from the Fukushima Dai-ichi Nuclear Power Plant exerted genetically and physiologically adverse effects on the pale grass blue butterfly Zizeeria maha in the Fukushima area. Immediately following publication, many questions and comments were generated from all over the world. Here, we have clarified points made in the original paper and answered questions posed by the readers. The following points were clarified. (1) There are many advantages to using the pale grass blue butterfly as an indicator species. (2) The forewings of the individuals collected in Fukushima were significantly smaller than in the northern and southern localities. (3) We observed growth retardation in the butterflies from the Fukushima area. (4) The aberrant colour patterns in the butterflies obtained in the Fukushima area were different from the colour patterns induced by temperature and sibling crosses but similar to those induced by external and internal exposures to the artificial radionuclides and by a chemical mutagen, suggesting that genetic mutations caused the aberrations. (5) This species of butterfly has been plentiful in Fukushima area for at least half a century. We here present specimens collected from Fukushima Prefecture before the accident. (6) Mutation accumulation was detected by the increase in the abnormality rates from May 2011 to September 2011. (7) The abnormal traits were heritable. (8) Our sampling localities were not affected by the tsunami. (9) We used a high enough number of samples to obtain statistically significant results. (10) The standard rearing method was followed, producing normal adults in the control groups. (11) The exposure experiments successfully reproduced the results of the field work. This species of butterfly is vulnerable to long-term low-dose internal and external exposures; however, insect cells are known to be

  17. Long-term exposures to low doses of silver nanoparticles enhanced in vitro malignant cell transformation in non-tumorigenic BEAS-2B cells.

    Science.gov (United States)

    Choo, Wun Hak; Park, Cho Hee; Jung, Shi Eun; Moon, Byeonghak; Ahn, Huiyeon; Ryu, Jung Seok; Kim, Keun-Soo; Lee, Yong Hwa; Yu, Il Je; Oh, Seung Min

    2016-12-01

    To predict carcinogenic potential of AgNPs on the respiratory system, BEAS-2B cells (human bronchial epithelial cells) were chronically exposed to low- and non-cytotoxic dose (0.13 and 1.33μg/ml) of AgNPs for 4months (#40 passages). To assess malignant cell transformation of chronic exposure to AgNPs, several bioassays including anchorage independent agar colony formation, cell migration/invasion assay, and epithelial-mesenchymal transition (EMT) were performed in BEAS-2B cells. Chronic exposure to AgNPs showed a significant increase of anchorage independent agar colony formation and cell migration/invasion. EMT, which is the loss of epithelial markers (E-Cadherin and Keratin) and the gain of mesenchymal marker (N-cadherin and Vimentin), was induced by chronic exposure to AgNPs. These responses indicated that chronic exposure to AgNPs could acquire characteristics of tumorigenic cells from normal BEAS-2B cells. In addition, caspase-3, p-p53, p-p38, and p-JNK were significantly decreased, while p-ERK1/2 was significantly increased. MMP-9 related to cell migration/invasion was upregulated, while a MMP-9 inhibitor, TIMP-1 was down-regulated. These results indicated that BEAS-2B cells exposed to AgNPs could induce anti-apoptotic response/anoikis resistance, and cell migration/invasion by complex regulation of MAPK kinase (p38, JNK, and ERK) and p53 signaling pathways. Therefore, we suggested that long-term exposure to low-dose of AgNPs could enhance malignant cell transformation in non-tumorigenic BEAS-2B cells. Our findings provide useful information needed to assess the carcinogenic potential of AgNPs.

  18. Long-term exposure of bacterial and protozoan communities to TiO2 nanoparticles in an aerobic-sequencing batch reactor

    Science.gov (United States)

    Supha, Chitpisud; Boonto, Yuphada; Jindakaraked, Manee; Ananpattarachai, Jirapat; Kajitvichyanukul, Puangrat

    2015-06-01

    Titanium dioxide (TiO2) nanopowders at different concentrations (0-50 mg L-1) were injected into an aerobic-sequencing batch reactor (SBR) to investigate the effects of long-term exposure to nanoparticles on bacterial and protozoan communities. The detection of nanoparticles in the bioflocs was analyzed by scanning electron microscopy, transmission electron microscopy, and energy-dispersive x-ray spectroscopy. The SBR wastewater experiments were conducted under the influence of ultraviolet light with photocatalytic TiO2. The intrusion of TiO2 nanoparticles was found both on the surface and inside of the bioflocs. The change of microbial population in terms of mixed liquor-suspended solids and the sludge volume index was monitored. The TiO2 nanoparticles tentatively exerted an adverse effect on the microbial population, causing the reduction of microorganisms (both bacteria and protozoa) in the SBR. The respiration inhibition rate of the bacteria was increased, and the viability of the microbial population was reduced at the high concentration (50 mg L-1) of TiO2. The decreasing number of protozoa in the presence of TiO2 nanoparticles during 20 days of treatment with 0.5 and 1.0 mg L-1 TiO2 is clearly demonstrated. The measured chemical oxygen demand (COD) in the effluent tends to increase with a long-term operation. The increase of COD in the system suggests a decrease in the efficiency of the wastewater treatment plant. However, the SBR can effectively remove the TiO2 nanoparticles (up to 50 mg L-1) from the effluent.

  19. Assessing the Health Effects of Long-Term Exposure to Insecticide-Treated Mosquito Nets in the Control of Malaria in Endemic Regions

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2004-01-01

    Full Text Available Malaria is a protozoan disease caused in humans by the genus Plasmodium of which four species are known: P. falciparum, P. vivax, P. ovale, and P. malariae. It is transmitted through the bite of infected female mosquitoes of the genus Anopheles. Malaria is endemic in tropical and subtropical regions of the world. It is characterized by extreme exhaustion associated with paroxysms of high fever, sweating, shaking chills, and anemia. Approximately 40% of the world's population, mostly those living in the poorest nations, are at risk. Much of the deaths due to malaria occur in Africa, mostly among children. The search for prevention and control interventions that are effective and sustainable remains an abiding challenge for national governments and international health agencies. To this end, the World Health Organization and several nongovernmental organizations are investing in the use of insecticide-treated mosquito nets (ITMNs as a viable option. Trials of ITMNs in the 1980s and 1990s showed that they reduce deaths in young children by an average of 20% and multilateral agencies, spearheaded by Roll Back Malaria (RBM, seek to have 60% of the populations at risk sleeping under ITMNs by 2005. All pesticides are toxic by nature and present risks of adverse effects that depend on toxicity of the chemical and the degree of exposure. While there is agreement that ITMNs can be effective in reducing malaria morbidity and mortality under field trials, a number of factors relating to their sustainability and contribution to health improvement in less-developed countries have yet to be determined. In particular, the adverse effects associated with their long-term use and misuse has yet to be fully evaluated. Although this paper examines potential neurotoxic and neurobehavioral effects of long-term use of ITMNs and discusses priority public health actions for protecting the health of users, it forms the basis for further research.

  20. Hepatic monooxygenase (CYP1A and CYP3A) and UDPGT enzymatic activities as biomarkers for long-term carbofuran exposure in tench (Tinca tinca L).

    Science.gov (United States)

    Hernández-Moreno, David; Soler-Rodríguez, Francisco; Míguez-Santiyán, M Prado; Pérez-López, Marcos

    2008-06-01

    The effect of a long-term exposure of tenchs to different concentrations (10 and 100 micro g/L) of the pesticide carbofuran has been evaluated. Microsomal hepatic cytochrome P450 subfamily 1A (CYP1A) and 3A (CYP3A) activities, as well as the phase II enzyme uridine diphospho-glucuronosyltransferase (UDPGT) activity were evaluated as adequate biomarkers of fish exposure to environmentally relevant concentrations of the pesticide carbofuran in freshwater ecosystems. A clear time-dependent inhibition of both CYP1A and UDPGT activities was observed in fish exposed to the highest dose of carbofuran with respect to controls, whereas in the case of CYP3A activity, values of exposed animals did not show a clear pattern of alteration during the experiment. The results of the present study demonstrated that hepatic CYP1A and UDPGT activities from tench could be considered as sensitive biomarkers for carbamate pesticides in polluted water, thus allowing future and ecologically relevant biomonitoring studies with this species.

  1. Exposure to Ionizing Radiation Causes Long-Term Increase in Serum Estradiol and Activation of PI3K-Akt Signaling Pathway in Mouse Mammary Gland

    Energy Technology Data Exchange (ETDEWEB)

    Suman, Shubhankar [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington, DC (United States); Johnson, Michael D. [Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States); Fornace, Albert J. [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington, DC (United States); Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States); Datta, Kamal, E-mail: kd257@georgetown.edu [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington, DC (United States)

    2012-10-01

    Purpose: Exposure to ionizing radiation is an established risk factor for breast cancer. Radiation exposure during infancy, childhood, and adolescence confers the highest risk. Although radiation is a proven mammary carcinogen, it remains unclear where it acts in the complex multistage process of breast cancer development. In this study, we investigated the long-term pathophysiologic effects of ionizing radiation at a dose (2 Gy) relevant to fractionated radiotherapy. Methods and Materials: Adolescent (6-8 weeks old; n = 10) female C57BL/6J mice were exposed to 2 Gy total body {gamma}-radiation, the mammary glands were surgically removed, and serum and urine samples were collected 2 and 12 months after exposure. Molecular pathways involving estrogen receptor-{alpha} (ER{alpha}) and phosphatidylinositol-3-OH kinase (PI3K)-Akt signaling were investigated by immunohistochemistry and Western blot. Results: Serum estrogen and urinary levels of the oncogenic estrogen metabolite (16{alpha}OHE1) were significantly increased in irradiated animals. Immunostaining for the cellular proliferative marker Ki-67 and cyclin-D1 showed increased nuclear accumulation in sections of mammary glands from irradiated vs. control mice. Marked increase in p85{alpha}, a regulatory sub-unit of the PI3K was associated with increase in Akt, phospho-Akt, phospho-BAD, phospho-mTOR, and c-Myc in irradiated samples. Persistent increase in nuclear ER{alpha} in mammary tissues 2 and 12 months after radiation exposure was also observed. Conclusions: Taken together, our data not only support epidemiologic observations associating radiation and breast cancer but also, specify molecular events that could be involved in radiation-induced breast cancer.

  2. Long-Term Effects of Radiation Exposure and Metabolic Status on Telomere Length of Peripheral Blood T Cells in Atomic Bomb Survivors.

    Science.gov (United States)

    Yoshida, Kengo; Misumi, Munechika; Kubo, Yoshiko; Yamaoka, Mika; Kyoizumi, Seishi; Ohishi, Waka; Hayashi, Tomonori; Kusunoki, Yoichiro

    2016-10-01

    In a series of studies of atomic bomb survivors, radiation-dose-dependent alterations in peripheral T-cell populations have been reported. For example, reduced size in naïve T-cell pools and impaired proliferation ability of T cells were observed. Because these alterations are also generally observed with human aging, we hypothesized that radiation exposure may accelerate the aging process of the T-cell immune system. To further test this hypothesis, we conducted cross-sectional analyses of telomere length, a hallmark of cellular aging, of naïve and memory CD4 T cells and total CD8 T cells in the peripheral blood of 620 atomic bomb survivors as it relates to age and radiation dose, using fluorescence in situ hybridization with flow cytometry. Since telomere shortening has been recently demonstrated in obesity-related metabolic abnormalities and diseases, the modifying effects of metabolic status were also examined. Our results indicated nonlinear relationships between T-cell telomere length and prior radiation exposure, i.e., longer telomeres with lower dose exposure and a decreasing trend of telomere length with individuals exposed to doses higher than 0.5 Gy. There were associations between shorter T-cell telomeres and higher hemoglobin Alc levels or fatty liver development. In naïve and memory CD4 T cells, radiation dose and high-density lipoprotein (HDL) cholesterol were found to positively interact with telomere length, suggesting that the decreasing trend of telomere length from a higher radiation dose was less conspicuous in individuals with a higher HDL cholesterol. It is therefore likely that radiation exposure perturbs T-cell homeostasis involving telomere length maintenance by multiple biological mechanisms, depending on dose, and that long-term-radiation-induced effects on the maintenance of T-cell telomeres may be modified by the subsequent metabolic conditions of individuals.

  3. Ability of palatable food consumption to buffer against the short- and long-term behavioral consequences of social defeat exposure during juvenility in rats.

    Science.gov (United States)

    MacKay, J C; Kent, P; James, J S; Cayer, C; Merali, Z

    2017-08-01

    In adult rats, access to a palatable diet can buffer against the effects of stressors. Approximately 10% of all adolescents are repeatedly victimized by their peers raising the possibility that palatable food consumption may be relevant to this developmental window. This study assessed the long-term impact of juvenile social defeat exposure on anxiety and depressive-like behavior and whether daily limited access to a palatable diet moderated these behavioral consequences. We also investigated the impact of the palatable diet on behavior during the defeat sessions. Juvenile rats were exposed to either a different adult resident rat (Stress) or handling (Control) from postnatal day (PD) 28-34. All rats had ad libitum access to either chow alone or both chow and limited access (4h/day) to palatable food commencing on PD 21. Results showed that during the defeat sessions, juvenile rats with access to the palatable diet spent less time in submissive postures and displayed significantly longer latencies to submit to the resident. In adulthood, previous exposure to juvenile social defeat resulted in a mild anxiogenic profile in the open field among rats with access to Chow only. Furthermore, defeated rats, regardless of diet, displayed reduced locomotor activity and increased social interaction as adults. These findings suggested only minimal enduring negative consequences from juvenile social defeat exposure which made it challenging to assess potential stress-buffering effects of the palatable diet. This was not the case during the defeat sessions where previous exposure to palatable food appeared protective against the acute stressor effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Long-Term Collections

    CERN Multimedia

    Comité des collectes à long terme

    2011-01-01

    It is the time of the year when our fireman colleagues go around the laboratory for their traditional calendars sale. A part of the money of the sales will be donated in favour of the long-term collections. We hope that you will welcome them warmly.

  5. In vitro chondrocyte toxicity following long-term, high-dose exposure to Gd-DTPA and a novel cartilage-targeted MR contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Midura, Sharon; Midura, Ronald J. [Cleveland Clinic, Biomedical Engineering, Lerner Research Institute, Cleveland, OH (United States); Schneider, Erika [Cleveland Clinic, Imaging Institute, A21, Cleveland, OH (United States); NitroSci Pharmaceuticals, New Berlin, WI (United States); Rosen, Gerald M. [University of Maryland School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, MD (United States); NitroSci Pharmaceuticals, New Berlin, WI (United States); Winalski, Carl S. [Cleveland Clinic, Biomedical Engineering, Lerner Research Institute, Cleveland, OH (United States); Cleveland Clinic, Imaging Institute, A21, Cleveland, OH (United States)

    2017-01-15

    To determine the concentrations exhibiting toxicity of a cartilage-targeted magnetic resonance imaging contrast agent compared with gadopentetate dimeglumine (Gd-DT-PA) in chondrocyte cultures. A long-term Swarm rat chondrosarcoma chondrocyte-like cell line was exposed for 48 h to 1.0-20 mM concentrations of diaminobutyl-linked nitroxide (DAB4-DLN) citrate, 1.0-20 mM Gd-DTPA, 1.0 μM staurosporine (positive control), or left untreated. Cell appearance, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays of metabolic activity, quantitative PicoGreen assays of DNA content, and calcein-AM viability assays were compared. At 1.0-7.5 mM, minimal decrease in cell proliferation was found for both agents. At all doses of both agents, cell culture appearances were similar after 24 h of treatment. At the higher doses, differences in cell culture appearance were found after 48 h of treatment, with dose-dependent declines in chondrocyte populations for both agents. Concentration-dependent declines in DNA content and calcein fluorescence were found after 48 h of treatment, but beginning at a lower dose of DAB4-DLN citrate than Gd-DTPA. Dose-dependent decreases in MTT staining (cell metabolism) were apparent for both agents, but larger effects were evident at a lower dose for DAB-DLN citrate. Poor MTT staining of cells exposed for 48 h to 20 mM DAB4-DLN citrate probably indicates dead or dying cells. The minimal effect of the long-term exposure of model chondrocyte cell cultures to DAB4-DLN citrate and Gd-DTPA concentrations up to 7.5 mM (3x typical arthrographic administration) is supporting evidence that these doses are acceptable for MR arthrography. The findings are reassuring given that the experimental exposure to the contrast agents at sustained concentrations was much longer than when used clinically. (orig.)

  6. Age-related impairment of long-term depression in area CA1 and dentate gyrus of rat hippocampus following developmental lead exposure in vitro.

    Science.gov (United States)

    Sui, L; Ge, S Y; Ruan, D Y; Chen, J T; Xu, Y Z; Wang, M

    2000-01-01

    Chronic developmental lead exposure is known to be associated with cognitive dysfunction in children. Impairment of the induction of long-term depression (LTD) has been reported in area CA1 and dentate gyrus (DG) of rat hippocampus following chronic lead exposure. The present study was carried out to investigate age-related alterations of LTD in area CA1 and DG of rat hippocampus following developmental lead exposure in vitro. Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams drinking 0.2% lead acetate solution. Field excitatory postsynaptic potentials (EPSPs) were recorded in hippocampal slices at various postnatal ages: postnatal day (PND) 17-23, 27-33, and 57-63. Following low-frequency stimulation (LFS, 900 pulses/1 Hz), the average magnitude of LTD is age related. In the controls, LTD magnitude in area CA1 decreased with age, whereas in DG it increased with age. In the lead-exposed groups, the magnitude of LTD declined during development in both area CA1 and DG. The differences of LTD magnitude between the control and lead-exposed rats were 27.26 +/- 9.15% (PND 17-23), 21.59 +/- 12.93% (PND 27-33), and 16.96 +/- 9.33% (PND 57-63) in area CA1, and were 6.95 +/- 9.26%, 17.60 +/- 3.91%, and 33.63 +/- 10.47% in DG, respectively. These results demonstrated that the lead-induced impairment of LTD magnitude was an age-related decline in area CA1 and an age-related increase in area DG of rat hippocampus. Published by Elsevier Science Inc.

  7. Protecting the Health of Astronauts: Enhancing Occupational Health Monitoring and Surveillance for Former NASA Astronauts to Understand Long-Term Outcomes of Spaceflight-Related Exposures

    Science.gov (United States)

    Rossi, Meredith; Lee, Lesley; Wear, Mary; Van Baalen, Mary; Rhodes, Bradley

    2017-01-01

    The astronaut community is unique, and may be disproportionately exposed to occupational hazards not commonly seen in other communities. The extent to which the demands of the astronaut occupation and exposure to spaceflight-related hazards affect the health of the astronaut population over the life course is not completely known. A better understanding of the individual, population, and mission impacts of astronaut occupational exposures is critical to providing clinical care, targeting occupational surveillance efforts, and planning for future space exploration. The ability to characterize the risk of latent health conditions is a significant component of this understanding. Provision of health screening services to active and former astronauts ensures individual, mission, and community health and safety. Currently, the NASA-Johnson Space Center (JSC) Flight Medicine Clinic (FMC) provides extensive medical monitoring to active astronauts throughout their careers. Upon retirement, astronauts may voluntarily return to the JSC FMC for an annual preventive exam. However, current retiree monitoring includes only selected screening tests, representing an opportunity for augmentation. The potential long-term health effects of spaceflight demand an expanded framework of testing for former astronauts. The need is two-fold: screening tests widely recommended for other aging populations are necessary to rule out conditions resulting from the natural aging process (e.g., colonoscopy, mammography); and expanded monitoring will increase NASA's ability to better characterize conditions resulting from astronaut occupational exposures. To meet this need, NASA has begun an extensive exploration of the overall approach, cost, and policy implications of e an Astronaut Occupational Health program to include expanded medical monitoring of former NASA astronauts. Increasing the breadth of monitoring services will ultimately enrich the existing evidence base of occupational health risks

  8. Long-term effects of adolescent exposure to bisphenol A on neuron and glia number in the rat prefrontal cortex: Differences between the sexes and cell type.

    Science.gov (United States)

    Wise, Leslie M; Sadowski, Renee N; Kim, Taehyeon; Willing, Jari; Juraska, Janice M

    2016-03-01

    Bisphenol A (BPA), an endocrine disruptor used in a variety of consumer products, has been found to alter the number of neurons in multiple brain areas in rats following exposure in perinatal development. Both the number of neurons and glia also change in the medial prefrontal cortex (mPFC) during adolescence, and this process is known to be influenced by gonadal hormones which could be altered by BPA. In the current study, we examined Long-Evans male and female rats that were administered BPA (0, 4, 40, or 400μg/kg/day) during adolescent development (postnatal days 27-46). In adulthood (postnatal day 150), the number of neurons and glia in the mPFC were stereologically assessed in methylene blue/azure II stained sections. There were no changes in the number of neurons, but there was a significant dose by sex interaction in number of glia in the mPFC. Pairwise comparisons between controls and each dose showed a significant increase in the number of glia between 0 and 40μg/kg/day in females, and a significant decrease in the number of glia between 0 and 4μg/kg/day in males. In order to determine the type of glial cells that were changing in these groups in response to adolescent BPA administration, adjacent sections were labelled with S100β (astrocytes) and IBA-1 (microglia) in the mPFC of the groups that differed. The number of microglia was significantly higher in females exposed to 40μg/kg/day than controls and lower in males exposed to 4μg/kg/day than controls. There were no significant effects of adolescent exposure to BPA on the number of astrocytes in male or females. Thus, adolescent exposure to BPA produced long-term alterations in the number of microglia in the mPFC of rats, the functional implications of which need to be explored.

  9. Below-ground carbon allocation in mature beech and spruce trees following long-term, experimentally enhanced O{sub 3} exposure in Southern Germany

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Christian P., E-mail: Andersen.christian@epa.go [US Environmental Protection Agency, Western Ecology Division, 200 SW 35th St., Corvallis, OR 97333 (United States); Ritter, Wilma [Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Gregg, Jillian [Terrestrial Ecosystems Research Associates, 200 SW 35th St., Corvallis, OR 97333 (United States); Matyssek, Rainer; Grams, Thorsten E.E. [Ecophysiology of Plants, Department of Ecology and Ecosystem Management, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany)

    2010-08-15

    Canopies of adult European beech (Fagus sylvatica) and Norway spruce (Picea abies) were labeled with CO{sub 2} depleted in {sup 13}C to evaluate carbon allocation belowground. One-half the trees were exposed to elevated O{sub 3} for 6 yrs prior to and during the experiment. Soil-gas sampling wells were placed at 8 and 15 cm and soil CO{sub 2} was sampled during labeling in mid-late August, 2006. In beech, {delta}{sup 13}CO{sub 2} at both depths decreased approximately 50 h after labeling, reflecting rapid translocation of fixed C to roots and release through respiration. In spruce, label was detected in fine-root tissue, but there was no evidence of label in {delta}{sup 13}CO{sub 2}. The results show that C fixed in the canopy rapidly reaches respiratory pools in beech roots, and suggest that spruce may allocate very little of recently-fixed carbon into root respiration during late summer. A change in carbon allocation belowground due to long-term O{sub 3} exposure was not observed. - Below-ground carbon allocation in mature beech and spruce exposed to ozone.

  10. Magnetic Fe3O4 nanoparticles induced effects on performance and microbial community of activated sludge from a sequencing batch reactor under long-term exposure.

    Science.gov (United States)

    Ma, Bingrui; Wang, Sen; Li, Zhiwei; Gao, Mengchun; Li, Shanshan; Guo, Liang; She, Zonglian; Zhao, Yangguo; Zheng, Dong; Jin, Chunji; Wang, Xuejiao; Gao, Feng

    2017-02-01

    The performance and microbial community of activated sludge from a sequencing batch reactor (SBR) were investigated under long-term exposure of magnetic Fe3O4 nanoparticles (Fe3O4 NPs). The COD removal showed a slight decrease at 5-60mg/L Fe3O4 NPs compared to 0mg/L Fe3O4 NPs, whereas the NH4(+)-N removal had no obvious variation at 0-60mg/L Fe3O4 NPs. It was found that 10-60mg/L Fe3O4 NPs improved the denitrification process and phosphorus removal of activated sludge. The microbial enzymatic activities of activated sludge could be affected by Fe3O4 NPs, which had similar variation trends to the nitrogen and phosphorus removal rates of activated sludge. The reactive oxygen species (ROS) production and lactate dehydrogenase (LDH) release demonstrated that Fe3O4 NPs led to the toxicity to activated sludge and destroyed the integrity of microbial cytomembrane. High throughput sequencing indicated that Fe3O4 NPs could obviously affect the microbial richness and diversity of activated sludge.

  11. Studies on the effect of long-term exposure to nitrogen dioxide on serum and liver proteins level and enzyme activity in guinea pigs.

    Science.gov (United States)

    Drozdz, M; Kucharz, E; Ludyga, K; Molska-Drozda, T

    1976-01-01

    Forty male guinea pigs were exposed to nitrogen dioxide in a concentration of 2 mg/m3, 8 hours daily for a period of 180 days. Forty male animals were used as a control group. The following changes were found in intoxicated animals: the decrease of total protein and seromucoid concentration in blood serum and the decrease of total protein, perchloric acid-soluble proteins, protein-bound hexosamines and sialic acids content, in liver tissue. Electrophoretic examination of the serum proteins showed the increase of alpha 1- and beta 2-globulins and the decrease of albumin concentration. Changes in the level of glycoproteins fractions and protein-bound carbohydrates in blood serum were described also. Estimation of enzymes activity showed the decrease of alanine and aspartate transaminase activity in blood serum caused by the strong decrease of the cytoplasmic fraction of these enzymes. However the simultaneous increase of the mitochondrial fraction of transaminases activity was observed. The decrease of the activity of choline esterase was found also. Similar changes of enzymes activity were found in liver tissue. Histopathological studies were done for the further clearing the influenze of nitrogen dioxide on serum and liver proteins concentration and enzymes activity. It was found that after long-term exposure to nitrogen dioxide the destruction processes may be observed in the liver. The possible mechanism of the nitrogen dioxide-induced damage of protein metabolism is discussed.

  12. Acute and Long-Term Effects of Noise Exposure on the Neuronal Spontaneous Activity in Cochlear Nucleus and Inferior Colliculus Brain Slices

    Directory of Open Access Journals (Sweden)

    Moritz Gröschel

    2014-01-01

    Full Text Available Noise exposure leads to an immediate hearing loss and is followed by a long-lasting permanent threshold shift, accompanied by changes of cellular properties within the central auditory pathway. Electrophysiological recordings have demonstrated an upregulation of spontaneous neuronal activity. It is still discussed if the observed effects are related to changes of peripheral input or evoked within the central auditory system. The present study should describe the intrinsic temporal patterns of single-unit activity upon noise-induced hearing loss of the dorsal and ventral cochlear nucleus (DCN and VCN and the inferior colliculus (IC in adult mouse brain slices. Recordings showed a slight, but significant, elevation in spontaneous firing rates in DCN and VCN immediately after noise trauma, whereas no differences were found in IC. One week postexposure, neuronal responses remained unchanged compared to controls. At 14 days after noise trauma, intrinsic long-term hyperactivity in brain slices of the DCN and the IC was detected for the first time. Therefore, increase in spontaneous activity seems to develop within the period of two weeks, but not before day 7. The results give insight into the complex temporal neurophysiological alterations after noise trauma, leading to a better understanding of central mechanisms in noise-induced hearing loss.

  13. Acute and long-term effects of noise exposure on the neuronal spontaneous activity in cochlear nucleus and inferior colliculus brain slices.

    Science.gov (United States)

    Gröschel, Moritz; Ryll, Jana; Götze, Romy; Ernst, Arne; Basta, Dietmar

    2014-01-01

    Noise exposure leads to an immediate hearing loss and is followed by a long-lasting permanent threshold shift, accompanied by changes of cellular properties within the central auditory pathway. Electrophysiological recordings have demonstrated an upregulation of spontaneous neuronal activity. It is still discussed if the observed effects are related to changes of peripheral input or evoked within the central auditory system. The present study should describe the intrinsic temporal patterns of single-unit activity upon noise-induced hearing loss of the dorsal and ventral cochlear nucleus (DCN and VCN) and the inferior colliculus (IC) in adult mouse brain slices. Recordings showed a slight, but significant, elevation in spontaneous firing rates in DCN and VCN immediately after noise trauma, whereas no differences were found in IC. One week postexposure, neuronal responses remained unchanged compared to controls. At 14 days after noise trauma, intrinsic long-term hyperactivity in brain slices of the DCN and the IC was detected for the first time. Therefore, increase in spontaneous activity seems to develop within the period of two weeks, but not before day 7. The results give insight into the complex temporal neurophysiological alterations after noise trauma, leading to a better understanding of central mechanisms in noise-induced hearing loss.

  14. Performance and microbial community of a sequencing batch biofilm reactor treating synthetic mariculture wastewater under long-term exposure to norfloxacin.

    Science.gov (United States)

    Zheng, Dong; Chang, Qingbo; Li, Zhiwei; Gao, Mengchun; She, Zonglian; Wang, Xuejiao; Guo, Liang; Zhao, Yangguo; Jin, Chunji; Gao, Feng

    2016-12-01

    The performance and microbial community of a sequencing batch biofilm reactor (SBBR) treating synthetic mariculture wastewater were evaluated under long-term exposure to norfloxacin (NFX) due to the overuse of antibiotics during the mariculture. The COD and NH4(+)-N removals had no distinct change at 0-6mgL(-1) NFX and were inhibited at 6-35mgL(-1) NFX. The specific oxygen uptake rate (SOUR), specific ammonium oxidation rate (SAOR), specific nitrite oxidation rate (SNOR) and specific nitrate reduction rate (SNRR) of the biofilm kept a decreasing tendency with the increase of NFX concentration from 0 to 35mgL(-1). The presence of NFX promoted the microorganisms to secrete more extracellular polymeric substances (EPS) and affected the chemical compositions of EPS. The microbial richness and diversity showed some obvious variations at different NFX concentrations. The present results demonstrated that NFX inhibited the SBBR performance and should decrease the NFX dosage in the mariculture. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Ventilatory long-term facilitation is evident after initial and repeated exposure to intermittent hypoxia in mice genetically depleted of brain serotonin.

    Science.gov (United States)

    Hickner, Stephen; Hussain, Najaah; Angoa-Perez, Mariana; Francescutti, Dina M; Kuhn, Donald M; Mateika, Jason H

    2014-02-01

    Our study was designed to determine if central nervous system (CNS) serotonin is required for the induction of ventilatory long-term facilitation (LTF) in intact, spontaneously breathing mice. Nineteen tryptophan hydroxylase 2-deficient (Tph2(-/-)) mice, devoid of serotonin in the CNS, and their wild-type counterparts (Tph2(+/+)) were exposed to intermittent hypoxia each day for 10 consecutive days. The ventilatory response to intermittent hypoxia was greater in the Tph2(+/+) compared with the Tph2(-/-) mice (1.10 ± 0.10 vs. 0.77 ± 0.01 ml min(-1)·percent(-1) oxygen; P ≤ 0.04). Ventilatory LTF, caused by increases in breathing frequency, was evident in Tph2(+/+) and Tph2(-/-) mice following exposure to intermittent hypoxia each day; however, the magnitude of the response was greater in the Tph2(+/+) compared with the Tph2(-/-) mice (1.11 ± 0.02 vs. 1.05 ± 0.01 normalized to baseline on each day; P ≤ 0.01). The magnitude of ventilatory LTF increased significantly from the initial to the finals days of the protocol in the Tph2(-/-) (1.06 ± 0.02 vs. 1.11 ± 0.03 normalized to baseline on the initial days; P ≤ 0.004) but not in the Tph2(+/+) mice. This enhanced response was mediated by increases in tidal volume. Body temperature and metabolic rate did not account for differences in the magnitude of ventilatory LTF observed between groups after acute and repeated daily exposure to intermittent hypoxia. We conclude that ventilatory LTF, after acute exposure to intermittent hypoxia, is mediated by increases in breathing frequency and occurs in the absence of serotonin, although the magnitude of the response is diminished. This weakened response is enhanced following repeated daily exposure to intermittent hypoxia, via increases in tidal volume, to a similar magnitude evident in Tph2(+/+) mice. Thus the magnitude of ventilatory LTF following repeated daily exposure to intermittent hypoxia is not dependent on the presence of CNS serotonin.

  16. Long-term exposure to elevated carbon dioxide does not alter activity levels of a coral reef fish in response to predator chemical cues.

    Science.gov (United States)

    Sundin, Josefin; Amcoff, Mirjam; Mateos-González, Fernando; Raby, Graham D; Jutfelt, Fredrik; Clark, Timothy D

    2017-01-01

    Levels of dissolved carbon dioxide (CO2) projected to occur in the world's oceans in the near future have been reported to increase swimming activity and impair predator recognition in coral reef fishes. These behavioral alterations would be expected to have dramatic effects on survival and community dynamics in marine ecosystems in the future. To investigate the universality and replicability of these observations, we used juvenile spiny chromis damselfish (Acanthochromis polyacanthus) to examine the effects of long-term CO2 exposure on routine activity and the behavioral response to the chemical cues of a predator (Cephalopholis urodeta). Commencing at ~3-20 days post-hatch, juvenile damselfish were exposed to present-day CO2 levels (~420 μatm) or to levels forecasted for the year 2100 (~1000 μatm) for 3 months of their development. Thereafter, we assessed routine activity before and after injections of seawater (sham injection, control) or seawater-containing predator chemical cues. There was no effect of CO2 treatment on routine activity levels before or after the injections. All fish decreased their swimming activity following the predator cue injection but not following the sham injection, regardless of CO2 treatment. Our results corroborate findings from a growing number of studies reporting limited or no behavioral responses of fishes to elevated CO2. Alarmingly, it has been reported that levels of dissolved carbon dioxide (CO2) forecasted for the year 2100 cause coral reef fishes to be attracted to the chemical cues of predators. However, most studies have exposed the fish to CO2 for very short periods before behavioral testing. Using long-term acclimation to elevated CO2 and automated tracking software, we found that fish exposed to elevated CO2 showed the same behavioral patterns as control fish exposed to present-day CO2 levels. Specifically, activity levels were the same between groups, and fish acclimated to elevated CO2 decreased their swimming

  17. Long-term p-nitrophenol exposure can disturb liver metabolic cytochrome P450 genes together with aryl hydrocarbon receptor in Japanese quail.

    Science.gov (United States)

    Ahmed, Eman; Nagaoka, Kentaro; Fayez, Mostafa; Samir, Haney; Watanabe, Gen

    2015-08-01

    P-Nitrophenol is a major metabolite of some organophosphorus compounds. It is considered to be one of nitrophenol derivatives of diesel exhaust particles that induce substantial hazards impacts on human and animal health. P-Nitrophenol (PNP) is a persistent organic pollutant. Consequently, bioaccumulation of PNP potentiates toxicity. The objectives of the current study were to assess the potential hepatic toxicity and pathway associated with long-term exposure to PNP. Japanese quails were orally administered different doses of PNP for 75 days. Liver and plasma samples were collected at days 45 (45D), days 60 (60D) and days 75 (75D). Liver histological changes and plasma corticosterone levels were assessed. Basal mRNA level of cytochromes P450 (CYP 450) (CYP1A4, 1A5, 1B1), heme oxygenase (HO-1), and aryl hydrocarbon receptor 1 (AhR1), from the liver of exposed birds and primary hepatocytes cultured for 24 hr with PNP, were analyzed using quantitative real-time PCR. The results revealed various histopathological changes in the liver, such as lymphocytes aggregation and hepatocytes degeneration. Significant increases in corticosterone levels were reported. After 60-days of in vivo exposure, the birds exhibited an overexpression in the liver CYP1A4, 1B1, AhR1, and HO-1. Furthermore, with continuous PNP administration, an overall downregulation of the tested genes was observed. In vitro, although a significant overexpression of CYP1A4, 1B1, and HO-1 was observed, CYP1A5 was downregulated. In conclusion, PNP can interfere with the liver CYP 450 enzymes and modulate HO-1 expression in the in vitro and in vivo experiments. Hence, it could have serious deleterious effects on humans, livestock, and wild animals.

  18. The effects of electromagnetic field exposure at short and long term of 900 mhz frequency emitted from mobile phones on rat bone tissue

    Directory of Open Access Journals (Sweden)

    Ahmet Aslan

    2011-12-01

    Full Text Available Objectives: There are increasing number of evidence that exposure to the radiofrequency fields from mobile phones could affect human health. An electromagnetic field (EMF has some biological effects on the behavior of the cell population of bone. The aim of this study was to investigate the effects of 900 MHz EMF emitted by mobile phones on the bone mineral density (BMD of rat bone tissue.Materials and methods: This study was done in Süleyman Demirel University, Turkey in 2006 . A total of 30 male rats were divided in three groups. EMF with 1±04 mW/cm2 power and 900 MHz frequency: Group I (n=10 was exposed to short term (ST 900 MHz EMF for 30 min/day, fıve day per week during 4 weeks, group II (n=10 was exposed to long term (LT 900 MHz EMF for 30 min/day fıve day per week during 8 weeks and group III (n=10 was non-irradiated as control group and was held in the same environmental conditions for the same time except EMF application. At the end of the experiment, BMD of all rats was measured by scanning with Dual Energy X-ray Absorptiometry.Results: Both lumbar spine and femur diaphysis BMD values were found to be lower in the exposed to ST or LT 900 MHz groups compared with the control group. However, the differences did not reach to a significant level (P>0.05.Conclusions: It can be said that exposure to ST or LT 900 MHz EMF acquired from cellular phones and/or similar sources with an average power intensity of 1.04 mW/cm2 and a SAR value of 0.008 W/kg has not significant effects on rats bone tissue BMD

  19. Long-term exposure to ambient air pollution and traffic noise and incident hypertension in seven cohorts of the European study of cohorts for air pollution effects (ESCAPE).

    Science.gov (United States)

    Fuks, Kateryna B; Weinmayr, Gudrun; Basagaña, Xavier; Gruzieva, Olena; Hampel, Regina; Oftedal, Bente; Sørensen, Mette; Wolf, Kathrin; Aamodt, Geir; Aasvang, Gunn Marit; Aguilera, Inmaculada; Becker, Thomas; Beelen, Rob; Brunekreef, Bert; Caracciolo, Barbara; Cyrys, Josef; Elosua, Roberto; Eriksen, Kirsten Thorup; Foraster, Maria; Fratiglioni, Laura; Hilding, Agneta; Houthuijs, Danny; Korek, Michal; Künzli, Nino; Marrugat, Jaume; Nieuwenhuijsen, Mark; Östenson, Claes-Göran; Penell, Johanna; Pershagen, Göran; Raaschou-Nielsen, Ole; Swart, Wim J R; Peters, Annette; Hoffmann, Barbara

    2017-04-01

    We investigated whether traffic-related air pollution and noise are associated with incident hypertension in European cohorts. We included seven cohorts of the European study of cohorts for air pollution effects (ESCAPE). We modelled concentrations of particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5), ≤10 µm (PM10), >2.5, and ≤10 µm (PMcoarse), soot (PM2.5 absorbance), and nitrogen oxides at the addresses of participants with land use regression. Residential exposure to traffic noise was modelled at the facade according to the EU Directive 2002/49/EC. We assessed hypertension as (i) self-reported and (ii) measured (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg or intake of BP lowering medication (BPLM). We used Poisson regression with robust variance estimation to analyse associations of traffic-related exposures with incidence of hypertension, controlling for relevant confounders, and combined the results from individual studies with random-effects meta-analysis. Among 41 072 participants free of self-reported hypertension at baseline, 6207 (15.1%) incident cases occurred within 5-9 years of follow-up. Incidence of self-reported hypertension was positively associated with PM2.5 (relative risk (RR) 1.22 [95%-confidence interval (CI):1.08; 1.37] per 5 µg/m³) and PM2.5 absorbance (RR 1.13 [95% CI:1.02; 1.24] per 10 - 5m - 1). These estimates decreased slightly upon adjustment for road traffic noise. Road traffic noise was weakly positively associated with the incidence of self-reported hypertension. Among 10 896 participants at risk, 3549 new cases of measured hypertension occurred. We found no clear associations with measured hypertension. Long-term residential exposures to air pollution and noise are associated with increased incidence of self-reported hypertension.

  20. γ-H2AX responds to DNA damage induced by long-term exposure to combined low-dose-rate neutron and γ-ray radiation.

    Science.gov (United States)

    Zhang, Junlin; He, Ying; Shen, Xianrong; Jiang, Dingwen; Wang, Qingrong; Liu, Qiong; Fang, Wen

    2016-01-01

    Risk estimates for low-dose radiation (LDR) remain controversial. The possible involvement of DNA repair-related genes in long-term low-dose-rate neutron-gamma radiation exposure is poorly understood. In this study, 60 rats were divided into control groups and irradiated groups, which were exposed to low-dose-rate n-γ combined radiation (LDCR) for 15, 30, or 60 days. The effects of different cumulative radiation doses on peripheral blood cell (PBC), subsets of T cells of peripheral blood lymphocytes (PBL) and DNA damage repair were investigated. Real-time PCR and immunoblot analyses were used to detect expression of DNA DSB-repair-related genes involved in the NHEJ pathway, such as Ku70 and Ku80, in PBL. The mRNA level of H2AX and the expression level of γ-H2AX were detected by real-time PCR, immunoblot, and flow cytometry. White blood cells (WBC) and platelets (PLT) of all ionizing radiation (IR) groups decreased significantly, while no difference was seen between the 30 day and 60 day exposure groups. The numbers of CD3(+), CD4(+) T cells and CD4(+)/CD8(+) in the PBL of IR groups were lower than in the control group. In the 30 day and 60 day exposure groups, CD8(+) T cells decreased significantly. Real-time PCR and immunoblot results showed no significant difference in the mRNA and protein expression of Ku70 and Ku80 between the control groups and IR groups. However, the mRNA of H2AX increased significantly, and there was a positive correlation with dose. There was no difference in the protein expression of γ-H2AX between 30 day and 60 day groups, which may help to explain the damage to PBL. In conclusion, PBL damage increased with cumulative dose, suggesting that γ-H2AX, but neither Ku70 nor Ku80, plays an important role in PBL impairment induced by LDCR. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Long-Term Collections

    CERN Multimedia

    Staff Association

    2016-01-01

    45 years helping in developing countries! CERN personnel have been helping the least fortunate people on the planet since 1971. How? With the Long-Term Collections! Dear Colleagues, The Staff Association’s Long-Term Collections (LTC) Committee is delighted to share this important milestone in the life of our Laboratory with you. Indeed, whilst the name of CERN is known worldwide for scientific discoveries, it also shines in the many humanitarian projects which have been supported by the LTC since 1971. Several schools and clinics, far and wide, carry its logo... Over the past 45 years, 74 projects have been supported (9 of which are still ongoing). This all came from a group of colleagues who wanted to share a little of what life offered them here at CERN, in this haven of mutual understanding, peace and security, with those who were less fortunate elsewhere. Thus, the LTC were born... Since then, we have worked as a team to maintain the dream of these visionaries, with the help of regular donat...

  2. Long-Term Collection

    CERN Document Server

    Staff Association

    2016-01-01

    Dear Colleagues, As previously announced in Echo (No. 254), your delegates took action to draw attention to the projects of the Long-Term Collections (LTC), the humanitarian body of the CERN Staff Association. On Tuesday, 11 October, at noon, small Z-Cards were widely distributed at the entrances of CERN restaurants and we thank you all for your interest. We hope to have achieved an important part of our goal, which was to inform you, convince you and find new supporters among you. We will find out in the next few days! An exhibition of the LTC was also set up in the Main Building for the entire week. The Staff Association wants to celebrate the occasion of the Long-Term Collection’s 45th anniversary at CERN because, ever since 1971, CERN personnel have showed great support in helping the least fortunate people on the planet in a variety of ways according to their needs. On a regular basis, joint fundraising appeals are made with the Directorate to help the victims of natural disasters around th...

  3. Collectes à long terme

    CERN Document Server

    Collectes à long terme

    2014-01-01

    En cette fin d’année 2014 qui approche à grands pas, le Comité des Collectes à Long Terme remercie chaleureusement ses fidèles donatrices et donateurs réguliers pour leurs contributions à nos actions en faveur des plus démunis de notre planète. C’est très important, pour notre Comité, de pouvoir compter sur l’appui assidu que vous nous apportez. Depuis plus de 40 ans maintenant, le modèle des CLT est basé principalement sur des actions à long terme (soit une aide pendant 4-5 ans par projet, mais plus parfois selon les circonstances), et sa planification demande une grande régularité de ses soutiens financiers. Grand MERCI à vous ! D’autres dons nous parviennent au cours de l’année, et ils sont aussi les bienvenus. En particulier, nous tenons à remercier...

  4. Anatase titanium dioxide nanoparticles in mice: evidence for induced structural and functional sperm defects after short-, but not long-, term exposure.

    Science.gov (United States)

    Smith, Michelle A; Michael, Rowan; Aravindan, Rolands G; Dash, Soma; Shah, Syed I; Galileo, Deni S; Martin-DeLeon, Patricia A

    2015-01-01

    Titanium dioxide (TiO 2 ) nanoparticles (TNPs) are widely used commercially and exist in a variety of products. To determine if anatase TNPs (ATNPs) in doses smaller than previously used reach the scrotum after entry in the body at a distant location and induce sperm defects, 100% ATNP (2.5 or 5 mg kg-1 body weight) was administered intraperitoneally to adult males for three consecutive days, followed by sacrifice 1, 2, 3, or 5 weeks later (long-) or 24, 48 or 120 h (short-term exposure). Transmission electron microscopy revealed the presence of ANTP in scrotal adipose tissues collected 120 h postinjection when cytokine evaluation showed an inflammatory response in epididymal tissues and fluid. At 120 h and up to 3 weeks postinjection, testicular histology revealed enlarged interstitial spaces. Significantly increased numbers of terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling-positive (apoptotic) germ (P = 0.002) and interstitial space cells (P = 0.04) were detected in treated males. Caudal epididymal sperm from the short-term, but not a long-term, arm showed significantly (P < 0.001) increased frequencies of flagellar abnormalities, excess residual cytoplasm (ERC), and unreacted acrosomes in treated versus controls (dose-response relationship). A novel correlation between ERC and unreacted acrosomes was uncovered. At 120 h, there were significant decreases in hyperactivated motility (P < 0.001) and mitochondrial membrane potential (P < 0.05), and increased reactive oxygen species levels (P < 0.00001) in treated versus control sperm. These results indicate that at 4-8 days postinjection, ANTP induce structural and functional sperm defects associated with infertility, and DNA damage via oxidative stress. Sperm defects were transient as they were not detected 10 days to 5 weeks postinjection.

  5. Effects of long-term progesterone exposure on porcine uterine gene expression: progesterone alone does not induce secreted phosphoprotein 1 (osteopontin) in glandular epithelium.

    Science.gov (United States)

    Bailey, Daniel W; Dunlap, Kathrin A; Erikson, David W; Patel, Atish K; Bazer, Fuller W; Burghardt, Robert C; Johnson, Greg A

    2010-10-01

    Pigs experience significant conceptus loss near mid-gestation, correlating with increasing glandular epithelial (GE) development and secretory activity. Secreted phosphoprotein 1 (SPP1, osteopontin) increases in GE between days 30 and 40 of pregnancy and is expressed in the GE of day 90 pseudopregnant pigs, suggesting that progesterone (P(4)) from corpora lutea is responsible for induction of SPP1 in GE. In this study, pigs were ovariectomized and treated daily with P(4) to assess effects of 40 days of P(4) exposure on SPP1, P(4) receptor (PGR), uteroferrin (ACP5), and fibroblast growth factor 7 (FGF7) expression in porcine endometria. PGR mRNA decreased in pigs injected with P(4) compared with pigs injected with corn oil (CO), and PGRs were downregulated in the luminal epithelium (LE) and GE. ACP5 mRNA increased in pigs injected with P(4) compared with pigs injected with CO, and ACP5 was induced in the GE of P(4)-treated pigs. FGF7 mRNA increased in pigs injected with P(4) compared with pigs injected with CO, and FGF7 was induced in the LE and GE of P(4)-treated pigs. SPP1 mRNA was not different between pigs injected with P(4) compared with pigs injected with CO, and SPP1 was not present in the GE of P(4)-treated pigs. Therefore, long-term P(4), in the absence of ovarian and/or conceptus factors, does not induce SPP1 expression in GE. We hypothesize that a servomechanism involving sequential effects of multiple hormones and cytokines, similar to those for sheep and humans, is required for GE differentiation and function, including the synthesis and secretion of SPP1.

  6. Long-term exposure of human gingival fibroblasts to cigarette smoke condensate reduces cell growth by modulating Bax, caspase-3 and p53 expression.

    Science.gov (United States)

    Alamri, A; Semlali, A; Jacques, É; Alanazi, M; Zakrzewski, A; Chmielewski, W; Rouabhia, M

    2015-08-01

    Smoking cigarettes increases the risk of oral tissue damage leading to periodontal disease. Gingival fibroblasts, the predominant cell type inhabiting gingival connective tissue, play a critical role in remodeling and maintaining gingival structure. The objective of this study was to investigate the effect of long-term exposure to cigarette smoke on human gingival fibroblast survival/apoptosis and the molecular pathways involved in these cell responses. Human gingival fibroblasts were extracted from healthy non-smokers and cultured in the presence of cigarette smoke condensate (CSC). At the end of each time point, cell growth was evaluated by means of MTT assay. Apoptotic and necrotic gene's expression was investigated by polymerase chain reaction array and by annexin V/propidium iodide staining and cell cycle assays. Western blot was used to investigate Bax and p53 proteins. These tests were supported by caspase 3 activity analyses. High levels of CSC decreased cell growth and deregulated cell cycle progression by increasing the G(0)/G(1) and reducing the S and G(2)/M phases of the gingival fibroblasts. Polymerase chain reaction arrays revealed the activation of several apoptotic genes by CSC, including TNF receptors, caspases, Bax and p53. This was supported by increases in the Bax and p53 protein levels as well as by an elevated activity of caspase-3 in the CSC-exposed cells. Immunofluorescence staining demonstrated that both Bax and caspase-3 displayed a cytosolic and mitochondrial distribution in the CSC-exposed gingival fibroblasts, compared to controls. The damaging effect of CSC on gingival fibroblast growth was also supported by the decrease in interleukin 6 and 8 secretion by the gingival fibroblasts. These results suggest that CSC may contribute to deregulating fibroblast functions. This can compromise fibroblast-epithelial cell interactions, which ultimately increases the risk of gingival tissue damage and the onset of periodontitis. © 2014 John Wiley

  7. Association of long-term PM2.5 exposure with mortality using different air pollution exposure models: impacts in rural and urban California.

    Science.gov (United States)

    Garcia, Cynthia A; Yap, Poh-Sin; Park, Hye-Youn; Weller, Barbara L

    2016-01-01

    Most PM2.5-associated mortality studies are not conducted in rural areas where mortality rates may differ when population characteristics, health care access, and PM2.5 composition differ. PM2.5-associated mortality was investigated in the elderly residing in rural-urban zip codes. Exposure (2000-2006) was estimated using different models and Poisson regression was performed using 2006 mortality data. PM2.5 models estimated comparable exposures, although subtle differences were observed in rate ratios (RR) within areas by health outcomes. Cardiovascular disease (CVD), ischemic heart disease (IHD), and cardiopulmonary disease (CPD), mortality was significantly associated with rural, urban, and statewide chronic PM2.5 exposures. We observed larger effect sizes in RRs for CVD, CPD, and all-cause (AC) with similar sizes for IHD mortality in rural areas compared to urban areas. PM2.5 was significantly associated with AC mortality in rural areas and statewide; however, in urban areas, only the most restrictive exposure model showed an association. Given the results seen, future mortality studies should consider adjusting for differences with rural-urban variables.

  8. Dietary exposure to polychlorinated biphenyls and dioxins from infancy until adulthood: A comparison between breast-feeding, toddler, and long-term exposure

    NARCIS (Netherlands)

    S. Patandin (Svati); P.C. Dagnelie (Pieter); E.L.M. Op de Coul (Eline); J.E. van der Veen; N. Weisglas-Kuperus (Nynke); P.J.J. Sauer (Pieter); P.G.H. Mulder (Paul)

    1999-01-01

    textabstractFood is the major source for polychlorinated biphenyl (PCB) and dioxin accumulation in the human body. Therefore, investigating food habits from early ages until reproductive age (25 years) is important in order to assess exposure risk for the next generatio

  9. Health in relation to occupational exposure to pesticides in the Dutch flower bulb culture : Part 2 : estimation of long-term exposure to pesticides

    NARCIS (Netherlands)

    Brouwer, D.H.; Brouwer, E.J.; Hemmen, J.J.

    1992-01-01

    As a part of an epidemiological study with a cross-sectional design aiming at the establishment of possible health effects due to the exposure to pesticides in the flower bulb culture, an occupational hygiene study has been conducted in order to discriminate or to rank participants according to the

  10. Long-term exposure to road traffic noise, ambient air pollution, and cardiovascular risk factors in the HUNT and lifelines cohorts.

    Science.gov (United States)

    Cai, Yutong; Hansell, Anna L; Blangiardo, Marta; Burton, Paul R; de Hoogh, Kees; Doiron, Dany; Fortier, Isabel; Gulliver, John; Hveem, Kristian; Mbatchou, Stéphane; Morley, David W; Stolk, Ronald P; Zijlema, Wilma L; Elliott, Paul; Hodgson, Susan

    2017-08-01

    Blood biochemistry may provide information on associations between road traffic noise, air pollution, and cardiovascular disease risk. We evaluated this in two large European cohorts (HUNT3, Lifelines). Road traffic noise exposure was modelled for 2009 using a simplified version of the Common Noise Assessment Methods in Europe (CNOSSOS-EU). Annual ambient air pollution (PM10, NO2) at residence was estimated for 2007 using a Land Use Regression model. The statistical platform DataSHIELD was used to pool data from 144 082 participants aged ≥20 years to enable individual-level analysis. Generalized linear models were fitted to assess cross-sectional associations between pollutants and high-sensitivity C-reactive protein (hsCRP), blood lipids and for (Lifelines only) fasting blood glucose, for samples taken during recruitment in 2006-2013. Pooling both cohorts, an inter-quartile range (IQR) higher day-time noise (5.1 dB(A)) was associated with 1.1% [95% confidence interval (95% CI: 0.02-2.2%)] higher hsCRP, 0.7% (95% CI: 0.3-1.1%) higher triglycerides, and 0.5% (95% CI: 0.3-0.7%) higher high-density lipoprotein (HDL); only the association with HDL was robust to adjustment for air pollution. An IQR higher PM10 (2.0 µg/m3) or NO2 (7.4 µg/m3) was associated with higher triglycerides (1.9%, 95% CI: 1.5-2.4% and 2.2%, 95% CI: 1.6-2.7%), independent of adjustment for noise. Additionally for NO2, a significant association with hsCRP (1.9%, 95% CI: 0.5-3.3%) was seen. In Lifelines, an IQR higher noise (4.2 dB(A)) and PM10 (2.4 µg/m3) was associated with 0.2% (95% CI: 0.1-0.3%) and 0.6% (95% CI: 0.4-0.7%) higher fasting glucose respectively, with both remaining robust to adjustment for air/noise pollution. Long-term exposures to road traffic noise and ambient air pollution were associated with blood biochemistry, providing a possible link between road traffic noise/air pollution and cardio-metabolic disease risk.

  11. Effects of long-term exposure to traffic-related air pollution on respiratory and cardiovascular mortality in the Netherlands: the NLCS-AIR study.

    Science.gov (United States)

    Brunekreef, Bert; Beelen, Rob; Hoek, Gerard; Schouten, Leo; Bausch-Goldbohm, Sandra; Fischer, Paul; Armstrong, Ben; Hughes, Edward; Jerrett, Michael; van den Brandt, Piet

    2009-03-01

    Evidence is increasing that long-term exposure to ambient air pollution is associated with deaths from cardiopulmonary diseases. In a 2002 pilot study, we reported clear indications that traffic-related air pollution, especially at the local scale, was related to cardiopulmonary mortality in a randomly selected subcohort of 5000 older adults participating in the ongoing Netherlands Cohort Study (NLCS) on diet and cancer. In the current study, referred to as NLCS-AIR, our objective was to obtain more precise estimates of the effects of traffic-related air pollution by analyzing associations with cause-specific mortality, as well as lung cancer incidence, in the full cohort of approximately 120,000 subjects. Cohort members were 55 to 69 years of age at enrollment in 1986. Follow-up was from 1987 through 1996 for mortality (17,674 deaths) and from late 1986 through 1997 for lung cancer incidence (2234 cases). Information about potential confounding variables and effect modifiers was available from the questionnaire that subjects completed at enrollment and from publicly available data (including neighborhood-scale information such as income distributions). The NLCS was designed for a case-cohort approach, which makes use of all the cases in the full cohort, while data for the random subcohort are used to estimate person-time experience in the study. Full information on confounders was available for the subjects in the random subcohort and for the emerging cases of mortality and lung cancer incidence during the follow-up period, and in NLCS-AIR we used the case-cohort approach to examine the relation between exposure to air pollution and cause-specific mortality and lung cancer. We also specified a standard Cox proportional hazards model within the full cohort, for which information on potential confounding variables was much more limited. Exposure to air pollution was estimated for the subjects' home addresses at baseline in 1986. Concentrations were estimated for

  12. Influence of long-term exposure to dietary cadmium on growth, maturation and reproduction of goldfish (subspecies: Prussian carp Carassius auratus gibelio B.)

    Energy Technology Data Exchange (ETDEWEB)

    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

  13. Estimation of excess mortality due to long-term exposure to PM2.5 in Japan using a high-resolution model for present and future scenarios

    Science.gov (United States)

    Goto, Daisuke; Ueda, Kayo; Ng, Chris Fook Sheng; Takami, Akinori; Ariga, Toshinori; Matsuhashi, Keisuke; Nakajima, Teruyuki

    2016-09-01

    Particulate matter with a diameter of less than 2.5 μm, known as PM2.5, can affect human health, especially in elderly people. Because of the imminent aging of society in the near future in most developed countries, the human health impacts of PM2.5 must be evaluated. In this study, we used a global-to-regional atmospheric transport model to simulate PM2.5 in Japan with a high-resolution stretched grid system (∼10 km for the high-resolution model, HRM) for the present (the 2000) and the future (the 2030, as proposed by the Representative Concentrations Pathway 4.5, RCP4.5). We also used the same model with a low-resolution uniform grid system (∼100 km for the low-resolution model, LRM). These calculations were conducted by nudging meteorological fields obtained from an atmosphere-ocean coupled model and providing emission inventories used in the coupled model. After correcting for bias, we calculated the excess mortality due to long-term exposure to PM2.5 among the elderly (over 65 years old) based on different minimum PM2.5 concentration (MINPM) levels to account for uncertainty using the simulated PM2.5 distributions to express the health effect as a concentration-response function. As a result, we estimated the excess mortality for all of Japan to be 31,300 (95% confidence intervals: 20,700 to 42,600) people in 2000 and 28,600 (95% confidence intervals: 19,000 to 38,700) people in 2030 using the HRM with a MINPM of 5.8 μg/m3. In contrast, the LRM resulted in underestimates of approximately 30% (for PM2.5 concentrations in the 2000 and 2030), approximately 60% (excess mortality in the 2000) and approximately 90% (excess mortality in 2030) compared to the HRM results. We also found that the uncertainty in the MINPM value, especially for low PM2.5 concentrations in the future (2030) can cause large variability in the estimates, ranging from 0 (MINPM of 15 μg/m3 in both HRM and LRM) to 95,000 (MINPM of 0 μg/m3 in HRM) people.

  14. Association between long-term exposure to air pollutants and prevalence of cardiovascular disease in 108 South Korean communities in 2008-2010: A cross-sectional study.

    Science.gov (United States)

    Lee, Whan Hee; Choo, Jee-Young; Son, Ji-Young; Kim, Ho

    2016-09-15

    Air pollution has been linked to cardiovascular disease, which is the leading cause of death worldwide. The aim of this study was to evaluate the epidemiological association between the yearly concentration of air pollution and regional prevalence of cardiovascular disease in South Korea. In this cross-sectional study, data regarding the regional prevalence of cardiovascular disease (i.e., hypertension, stroke, myocardial infarction, and angina) and health behaviors were obtained from the Korean Community Health Survey conducted in 108 communities of South Korea in 2008-2010. Data on carbon monoxide (CO; ppb), nitrogen dioxide (NO2; ppb), and particulate matter up to 10μm in size (PM10; μg/m(3)) were collected from the National Institute of Environmental Research. We used a distributed lag model with generalized estimating equations to represent the corrected lag-response and correlation among repeated observations. Cumulative odds ratios of hypertension, hypertension in those aged >30years, stroke, and angina with an increase of 10μg/m(3) in PM10 were 1.042 (95% confidence interval [CI]: 1.009, 1.077), 1.044 (CI: 1.009, 1.079), 1.044 (CI: 0.979, 1.114), and 0.977 (CI: 0.901, 1.059), respectively; a 10ppb increase in NO2 was associated with an odds ratio of 1.077 (CI: 1.044, 1.112), 1.08 (CI: 1.043, 1.118), 1.073 (CI: 0.994, 1.157), and 1.047 (CI: 0.968, 1.134), respectively. A 10ppb increase in CO was associated with an odds ratio of 1.123 (CI: 0.963, 1.31), 1.129 (CI: 0.963, 1.387), and 1.336 (CI: 0.9887, 2.011) for hypertension, hypertension in patients >30years, and stroke >50, respectively. We found suggestive evidence of an association between the long-term exposure (i.e., delayed for 5years) to air pollutants (i.e., PM10, NO2, and CO) and the regional prevalence of chronic cardiovascular disease (i.e., hypertension, stroke, myocardial infarction, and angina) in 108 communities in South Korea.

  15. LONG TERM COLLECTIONS

    CERN Multimedia

    STAFF ASSOCIATION

    2010-01-01

    ACKNOWLEDGMENTS The Long-Term Collections (CLT) committee would like to warmly thank its faithful donors who, year after year, support our actions all over the world. Without you, all this would not be possible. We would like to thank, in particular, the CERN Firemen’s Association who donated 5000 CHF in the spring thanks to the sale of their traditional calendar, and the generosity of the CERN community. A huge thank you to the firemen for their devotion to our cause. And thank you to all those who have opened their door, their heart, and their purses! Similarly, we warmly thank the CERN Yoga Club once again for its wonderful donation of 2000 CHF we recently received. We would also like to tell you that all our projects are running well. Just to remind you, we are currently supporting the activities of the «Réflexe-Partage» Association in Mali; the training centre of «Education et Développement» in Abomey, Benin; and the orphanage and ...

  16. The Exposure of Breast Cancer Cells to Fulvestrant and Tamoxifen Modulates Cell Migration Differently

    Directory of Open Access Journals (Sweden)

    Dionysia Lymperatou

    2013-01-01

    Full Text Available There is no doubt that there are increased benefits of hormonal therapy to breast cancer patients; however, current evidence suggests that estrogen receptor (ER blockage using antiestrogens is associated with a small induction of invasiveness in vitro. The mechanism by which epithelial tumor cells escape from the primary tumor and colonize to a distant site is not entirely understood. This study investigates the effect of two selective antagonists of the ER, Fulvestrant (Fulv and Tamoxifen (Tam, on the invasive ability of breast cancer cells. We found that 17β-estradiol (E2 demonstrated a protective role regarding cell migration and invasion. Fulv did not alter this effect while Tam stimulated active cell migration according to an increase in Snail and a decrease in E-cadherin protein expression. Furthermore, both tested agents increased expression of matrix metalloproteinases (MMPs and enhanced invasive potential of breast cancer cells. These changes were in line with focal adhesion kinase (FAK rearrangement. Our data indicate that the anti-estrogens counteracted the protective role of E2 concerning migration and invasion since their effect was not limited to antiproliferative events. Although Fulv caused a less aggressive result compared to Tam, the benefits of hormonal therapy concerning invasion and metastasis yet remain to be investigated.

  17. One year of adjuvant tamoxifen compared with chemotherapy and tamoxifen in postmenopausal patients with stage II breast cancer

    DEFF Research Database (Denmark)

    Ejlertsen, Bent; Jensen, Maj-Britt; Elversang, Johanna

    2013-01-01

    We report the long-term results of a randomised trial comparing tamoxifen with tamoxifen plus cyclophosphamide, methotrexate and fluorouracil (CMF) in postmenopausal high-risk breast cancer patients. In addition, we analyse the prognostic and predictive value of centrally assessed subtypes....

  18. MORPHOLOGICAL FEATURES OF LUNG STRUCTURE AND FUNCTIONAL ACTIVITY OF THE AIRWAYS OF GUINEA PIGS AFTER LONG-TERM EXPOSURE WITH NANOSIZED MAGNETITE A

    Directory of Open Access Journals (Sweden)

    Ye. Ye. Abramenko

    2013-01-01

    Full Text Available The results of study, in which we examined the influence of nanosized magnetite on breath organs histological structure and contractility activity of the airways of guinea pigs by method of mechanography has been presented. In the lungs of experimental animals an inflammatory response developed as a result of long-term inhalation intake of nanosized magnetite. Also the functional status of the airways changed and appeared as changing of amplitude of contractility response under the action of histamine.

  19. Effects of Long-Term Low-Level Radiofrequency Radiation Exposure on Rats. Volume 6. Hematological, Serum Chemistry, Thyroxine, and Protein Electrophoresis Evaluations.

    Science.gov (United States)

    1984-03-01

    111I. 11 MICROCOPY RESOLUTION TESI CHART i ~ ~ ~ ~ ~ ~ ~ ~ ~ A N... DS................. ...".... , II I - I Reort USAFSAM-TR-84-2 EFFECTS OF LONG-TERM...obstruction, and resolving internal hemorrhage. The total levels are decreased in cases of bone-marrow-depression anemia . The direct and indirect...VIR" 4 THYROXINE Elevated contents of serum cholestrol and triglycerides and a mild normochromic, norioocytic anemia are nonspecific traits suggestive

  20. Passive sampling of wastewater as a tool for the long-term monitoring of community exposure: Illicit and prescription drug trends as a proof of concept.

    Science.gov (United States)

    Baz-Lomba, J A; Harman, Christopher; Reid, Malcolm; Thomas, Kevin V

    2017-09-15

    A passive sampling device, the Polar Organic Chemical Integrative Sampler (POCIS), was calibrated in-situ over a 4-week period in Oslo (Norway) for 10 illicit drugs and pharmaceuticals with the goal of developing an approach for monitoring long-term wastewater drug loads. The calibrations were performed in triplicate using three different overlapping calibration sets under changing environmental conditions that allowed the uncertainty of the sampling rates to be evaluated. All 10 compounds exhibited linear uptake kinetics and provided sampling rates of between 0.023 and 0.192 L d(-1). POCIS were deployed for consecutive 2-week periods during 2012 and 2013 and the calculated time-weighted average (TWA) concentrations used to define different drug use trends. The relative uncertainty related to the POCIS data was approximately 40% and, except for citalopram, 85% of all the long-term measurements of pharmaceuticals were within the confidence interval levels calculated to evaluate the effects of changing environmental conditions on the TWA estimations. POCIS was demonstrated to be sufficiently robust to provide reliable annual drug use estimates with a smaller number of samplers (n = 24) than recommended for active sampling (n = 56) within an acceptable level of sample size related uncertainty POCIS is demonstrated to be a valuable and reliable tool for the long-term monitoring of certain drugs and pharmaceuticals within a defined population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The effect of communication change on long-term reductions in child exposure to conflict: impact of the promoting strong African American families (ProSAAF) program.

    Science.gov (United States)

    Beach, Steven R H; Barton, Allen W; Lei, Man Kit; Brody, Gene H; Kogan, Steven M; Hurt, Tera R; Fincham, Frank D; Stanley, Scott M

    2014-12-01

    African American couples (n = 331) with children, 89% of whom were married, were assigned to either (a) a culturally sensitive couple- and parenting-enhancement program (ProSAAF) or (b) an information-only control condition in which couples received self-help materials. Husbands averaged 41 years of age and wives averaged 39 years. We found significant effects of program participation in the short term on couple communication, which was targeted by the intervention, as well as over the long term, on self-reported arguing in front of children. Long-term parenting outcomes were fully mediated by changes in communication for wives, but not for husbands. For husbands, positive change depended on amount of wife reported change. We conclude that wives' changes in communication from baseline to posttest may be more pivotal for the couples' long-term experience of decreased arguing in front of children than are husbands' changes, with wives' changes leading to changes in both partners' reports of arguments in front of children. © 2014 Family Process Institute.

  2. [Long-term effects of mild hyperglycemia exposure in utero and postnatal high fat diet on body weight and lipid metabolism in rat offsprings].

    Science.gov (United States)

    Zhang, Kai; Li, Xin; Yang, Hui-xia

    2013-08-01

    To investigate the long-term effects of intrauterine mild hyperglycemia exposure and postnatal high fat diet on the body weight and metabolism of offspring through a pregnant rat model of intrauterine mild hyperglycemia. Twenty-one pregnant Wistar rats were randomly divided into intrauterine hyperglycemia group and control group. Twenty percent streptozotocin (STZ, 25 mg/kg)was given to rats of intrauterine hyperglycemia group by a single intraperitoneal injection to induce intrauterine mild hyperglycemia; control group rats received an equal volume of citric acid-sodium citrate buffer. Off springs were divided into 4 groups: exposed to intrauterine hyperglycemia and fed with normal diet group (group DN) or high fat diet group (group DF); exposed to intrauterine euglycemia and fed with normal diet group (group CN) or high fat diet group (group CF). The blood glucose levels of pregnant rats in two groups and body weights of offsprings in four groups were recorded. At the age of 28 weeks, the mesenteric fat amount, epididymal amount, perirenal fat amount, total triglyceride (TG) and high density 1ipoprotein-cholestrol (HDL-C) were measured in all four groups. (1)The average blood glucose level of intrauterine hyperglycemia group [(16.6 ± 3.4) mmol/L] was significantly higher than that of the control group [(5.8 ± 1.1) mmol/L, P weight of group DN[(7.4 ± 0.6), (44.1 ± 5.9), (79.6 ± 7.4) g] and group DF [(7.4 ± 0.2), (43.9 ± 6.9), (76.1 ± 5.8) g] were remarkably increased compared with group CN [(6.6 ± 0.5),(35.6 ± 4.4),(71.5 ± 6.8) g, P weight in group CF [(6.7 ± 0.5),(33.0 ± 6.5),(66.1 ± 10.2) g] had no statistical difference compared with group CN (P > 0.05). (3)From then on, the body weights of the offsprings in four groups presented an increasing trend, but there was no statistical difference until 28 weeks (P > 0.05). (4) The perirenal fat amount of group DN, group CF and group DF [(13.8 ± 3.3), (14.3 ± 3.2), (18.4 ± 1.3) g] were remarkably

  3. Meta-analysis on the Influence of Long-term Exposure to Pesticides on Female Reproductive System%长期农药接触对女性生殖系统功能影响的Meta分析

    Institute of Scientific and Technical Information of China (English)

    孔文明; 陈金磊; 肖国兵

    2011-01-01

    目的 综合分析长期农药接触对女性生殖系统的影响.方法 检索并筛检近年来发表的关于长期农药接触对女性生殖系统影响的研究文献,将结果录入RevMan 4.2进行Meta分析,应用固定效用模型和随机效应模型进行OR值合并.结果 共有8篇文献符合纳入标准,长期农药接触与女性月经异常、自然流产和早产有相关性,合并OR值分别为4.36、2.43和2.20.结论 长期农药接触可影响女性生殖功能,使女性的月经和各种生殖结局产生异常.%Objective To evaluate the influence of long - term exposure to pesticides on female reproductive system.Methods Data corresponding to long - term exposure to pesticides were collected through literature retrieval.The meta - analysis was performed on RevMan4.2 software.Both fixed effect model and random effect model were applied to calculate the merged OR.Results Eight studies were included, and long- term exposure to pesticides was associated with female abnormal menstruation, spontaneous abortion, stillbirth, and premature birth, with the merged OR values were 4.36, 2.43, and 2.20, respectively.Conclusion Long - term exposure to pesticides could have negative effects on female reproductive function, leading to abnormality in menstruation and reproductive outcome.

  4. Subchronic nicotine exposure in adolescence induces long-term effects on hippocampal and striatal cannabinoid-CB1 and mu-opioid receptors in rats.

    Science.gov (United States)

    Marco, Eva M; Granstrem, Oleg; Moreno, Enrique; Llorente, Ricardo; Adriani, Walter; Laviola, Giovanni; Viveros, Maria-Paz

    2007-02-14

    There is evidence for the existence of functional interactions between nicotine and cannabinoids and opioid compounds in adult experimental animals. However, there is scarce information about these relationships in young animals. In the present study we evaluated short and long-term effects of a subchronic nicotine treatment [0.4 mg/kg daily i.p. injections from postnatal day (PND) 34 to PND 43], upon hippocampal and striatal cannabinoid-CB(1) and mu-opioid receptors in Wistar rats of both genders. Rats were sacrificed 2 h after the last nicotine injection (short-term effects, PND 43) or one month later (long-term effects, PND 75). Hippocampal and striatal cannabinoid CB(1) and mu-opioid receptors were quantified by Western blotting. The subchronic nicotine treatment induced a region-dependent long-lasting effect in cannabinoid CB(1) receptor: a significant increase in hippocampal cannabinoid CB(1) receptors and a significant decrease in striatal cannabinoid CB(1) receptors, with these effects being similar in males and females. With respect to mu-opioid receptors, subchronic nicotine induced a significant down-regulation in hippocampal and striatal mu-opioid receptors in the long-term, and within the striatum the effects were more marked in adult males than in females. The present results indicate that juvenile nicotine taking may have implications for the endocannabinoid and endogenous opioid function and for the behaviors served by those systems, this includes possible modification of the response of adults to different psychotropic drugs, i.e. cannabis and morphine/heroin when taken later in life.

  5. Variability in the intraspecific response of Pinus ponderosa seedlings subjected to long-term exposure to elevated CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Houpis, J.L.J.; Anschel, D.J. [Lawrence Livermore National Lab., CA (United States). Health and Ecological Assessment Div.; Pushnik, J.C. [California State Univ., Chico, CA (United States). Dept. of Biological Sciences; Anderson, P.D. [Forest Service, Rhinelander, WI (United States)

    1995-01-01

    The authors are investigating the effects of elevated CO{sub 2} and intraspecific variability on Pinus ponderosa. To analyze intraspecific variability, they included seedling source (family) as an additional treatment, using a split-plot experimental design. The three elevated CO{sub 2} treatments were ambient (approx. 350 ppm CO{sub 2}), ambient + 175 ppm CO{sub 2} and ambient +350 ppm CO{sub 2}. Their study uses the source/sink control framework at several key integrating steps, incorporating the long-term effects of elevated CO{sub 2} (insuring sufficient time for the expression of any long-term physiological and biochemical acclimation to occur) and genetics (using multiple species and multiple known genetic sources) in an attempt to ascertain the extent of overall regulation contributed by selected independent regulatory process at the physiological, biochemical and structural level. In order to assess intraspecific variability, this paper reports on the integration of measurements of photosynthesis, chlorophyll fluorescence, pigmentation, RuBPCase, SPSase to quantify the effects of elevated CO{sub 2} on the growth response of various families of the same species.

  6. Changes In Properties and Microstructure of High-Chromium 9-12%Cr Steels Due to Long-Term Exposure at Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Zieliński A.

    2016-06-01

    Full Text Available This paper presents the characteristics of the performance of P91 (X10CrMoVNb9-1, P92 (X10CrWMoVNb9-2 and VM12 (X12CrCoWVNb12-2-2 steels used for condition assessment of the pressure components of boilers with supercritical steam parameters. Studies on the mechanical properties, microstructure tests using scanning and transmission electron microscopy, and X-ray analysis of the phase composition of precipitates were performed for selected steels in the as-received condition and after long-term annealing. These steel characteristics are used for the evaluation of the microstructural changes and mechanical properties of the material of components after long-term service. The result of this study is the database of material characteristics representing the mechanical properties related to the microstructure analysis and it can be used for diagnosis of the components of pressure parts of power boilers.

  7. Long-term urethral catheterisation.

    Science.gov (United States)

    Turner, Bruce; Dickens, Nicola

    This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

  8. Vertical flux of phytoplankton and particulate matter in the White Sea according to the long-term exposure of sediment traps

    Science.gov (United States)

    Ilyash, L. V.; Radchenko, I. G.; Novigatsky, A. N.; Lisitzin, A. P.; Shevchenko, V. P.

    2013-03-01

    The vertical fluxes of phytoplankton (VFPhyto) and particulate organic carbon (VFPOC) in the White Sea were determined using seven long-term (292 to 296 days) sediment traps moored at five stations at 67-255 m depths. The annual VFPhyto and VFPOC ranged from 0.55 to 24.64 g C/m2 and from 3.7 to 93.9 g C/m2, respectively. The highest VFPhyto was observed in the Basin region located close to the Gorlo along the Tersk coast. The algal biomass accounted for 15-43% of the VFPOC. Diatoms comprised the most important group, accounting for 83-100% in the sedimented biomass. Thalassiosira nordenskioeldii dominated in the VFPhyto at all the stations except for the station in the basin close to Onega Bay, where Ditylum brightwellii was the most abundant.

  9. Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health.

    Science.gov (United States)

    Ross, Jennifer A; Shipp, Eva M; Trueblood, Amber B; Bhattacharya, Amit

    2016-08-01

    To honor Tom Waters's work on emerging occupational health issues, we review the literature on physical along with chemical exposures and their impact on functional outcomes. Many occupations present the opportunity for exposure to multiple hazardous exposures, including both physical and chemical factors. However, little is known about how these different factors affect functional ability and injury. The goal of this review is to examine the relationships between these exposures, impairment of the neuromuscular and musculoskeletal systems, functional outcomes, and health problems with a focus on acute injury. Literature was identified using online databases, including PubMed, Ovid Medline, and Google Scholar. References from included articles were searched for additional relevant articles. This review documented the limited existing literature that discussed cognitive impairment and functional disorders via neurotoxicity for physical exposures (heat and repetitive loading) and chemical exposures (pesticides, volatile organic compounds [VOCs], and heavy metals). This review supports that workers are exposed to physical and chemical exposures that are associated with negative health effects, including functional impairment and injury. Innovation in exposure assessment with respect to quantifying the joint exposure to these different exposures is especially needed for developing risk assessment models and, ultimately, preventive measures. Along with physical exposures, chemical exposures need to be considered, alone and in combination, in assessing functional ability and occupationally related injuries. © 2016, Human Factors and Ergonomics Society.

  10. Long-term, low-level exposure of guinea pigs and marmosets to sarin vapor in air: Lowest observable effect level

    NARCIS (Netherlands)

    Helden, H.P.M. van; Trap, H.C.; Oostdijk, J.P.; Kuijpers, W.C.; Langenberg, J.P.; Benschop, H.P.

    2003-01-01

    Realistic scenarios for low-level exposure to nerve agents will often involve exposures over several hours to extremely low doses of agent. In order to expose animals to the lowest controllable concentrations of agent and to increase exposure times until a lowest observable effect level (LOEL)

  11. [Autoimmune processes after long-term low-level exposure to electromagnetic fields (the results of an experiment). Part 1. Mobile communications and changes in electromagnetic conditions for the population. Needs for additional substantiation of the existing hygienic standards].

    Science.gov (United States)

    Grigor'ev, Iu G; Grigor'ev, O A; Ivanov, A A; Liaginskaia, A M; Merkulov, A V; Stepanov, V S; Shagina, N B

    2010-01-01

    Mobile communications provides a new source of electromagnetic exposure for almost the whole population of the Russian Federation. For the first time in the history of civilization the brain of mobile phone users was exposed to localized radiofrequency (RF) electromagnetic fields (EMF). Population exposure from the base stations is also considered to be specific. However, existing standards for limiting the exposure do not account for this special EMF source and may not ensure the absence of health effects. There was a need for reliable information that would extend databases used for development of new standards. As recommended by the World Health Organization an additional experiment was performed under the supervision of foreign experts, which showed changes in autoimmune status in rats after long-term low-level RF EMF exposure with an incident power density of 500 microW/cm2.

  12. Comment on ''Effects of long-term high CO2 exposure on two species of coccolithophore'' by Müller et al. (2010

    Directory of Open Access Journals (Sweden)

    S. Collins

    2010-07-01

    Full Text Available Populations can respond to environmental change over tens or hundreds of generations by shifts in phenotype that can be the result of a sustained physiological response, evolutionary (genetic change, shifts in community composition, or some combination of these factors. Microbes evolve on human timescales, and evolution may contribute to marine phytoplankton responses to global change over the coming decades. However, it is still unknown whether evolutionary responses are likely to contribute significantly to phenotypic change in marine microbial communities under high pCO2 regimes or other aspects of global change. Recent work by Müller et al. (2010 highlights that long-term responses of marine microbes to global change must be empirically measured and the underlying cause of changes in phenotype explained. Here, I briefly discuss how tools from experimental microbial evolution may be used to detect and measure evolutionary responses in marine phytoplankton grown in high CO2 environments and other environments of interest. I outline why the particular biology of marine microbes makes conventional experimental evolution challenging right now and make a case that marine microbes are good candidates for the development of new model systems in experimental evolution. I suggest that "black box" frameworks that focus on partitioning phenotypic change, such as the Price equation, may be useful in cases where direct measurements of evolutionary responses alone are difficult, and that such approaches could be used to test hypotheses about the underlying causes of phenotypic shifts in marine microbe communities responding to global change.

  13. Effects of long-term exposure of 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy") on neuronal transmitter transport, brain immuno-regulatory systems and progression of experimental periodontitis in rats.

    Science.gov (United States)

    Breivik, Torbjørn; Bogen, Inger Lise; Haug, Kristin Huse; Fonnum, Frode; Opstad, Per-Kristian; Eide, Dag Marcus; Myhre, Oddvar

    2014-06-01

    The present study was designed to investigate the effects of long-term exposure (4 weeks) to the widely used narcotic drug and putative neurotoxicant 3,4-methylenedioxymetamphetamine (MDMA; "ecstasy") on neuronal transmitter transport and progression of experimental periodontitis in male Wistar rats. The rats were exposed to MDMA (10mg/kg/day i.p.) or saline five days a week for four consecutive weeks. Exposure to MDMA induced a significant reduction in the synaptosomal reuptake of serotonin, while the uptake of dopamine was significantly increased 24h after the last injection of MDMA. In contrast, the synaptosomal uptake of noradrenaline and the vesicular uptake through the vesicular monoamine transporter 2 were not affected. In the experiments of periodontitis development, ligature-induced periodontitis was induced three days prior to MDMA administration. Compared to controls, MDMA-treated rats developed significantly more periodontitis. In conclusion, our results show that long-term exposure to MDMA affects the serotonergic and dopaminergic transport systems in the rat brain and increased the susceptibility to the psychosomatic ailment periodontitis following disturbances of brain immune-regulatory systems. These results are interesting with respect to recent research showing that changes in neurotransmitter signalling may alter the reactivity of brain-controlled immunoregulatory systems controlling pathogenic microorganisms colonizing mucosal surfaces.

  14. Same Exposure but two radically different responses to antibiotics: Resilience of the salivary microbiome versus long-term microbial shifts in feces

    NARCIS (Netherlands)

    Zaura, E.; Brandt, B.W.; Mattos, M.J.T. de; Buijs, M.J.; Caspers, M.P. M.; Rashid, M.U.; Weintraub, A.; Nord, C.E.; Savell, A.; Hu, Y.; Coates, A.R.; Hubank, M.; Spratt, D.A.; Wilson, M.; Keijser, B.J.F.; Crielaard, W.

    2015-01-01

    Due to the spread of resistance, antibiotic exposure receives increasing attention. Ecological consequences for the different niches of individual microbiomes are, however, largely ignored. Here, we report the effects of widely used antibiotics (clindamycin, ciprofloxacin, amoxicillin, and

  15. Same exposure but two radically different responses to antibiotics: resilience of the salivary microbiome versus long-term microbial shifts in feces

    NARCIS (Netherlands)

    Zaura, E.; Brandt, B.W.; Teixeira de Mattos, M.J.; Buijs, M.J.; Caspers, M.P.M.; Rashid, M.U.; Weintraub, A.; Nord, C.E.; Savell, A.; Hu, Y.; Coates, A.R.; Hubank, M.; Spratt, D.A.; Wilson, M.; Keijser, B.J.F.; Crielaard, W.

    2015-01-01

    Due to the spread of resistance, antibiotic exposure receives increasing attention. Ecological consequences for the different niches of individual microbiomes are, however, largely ignored. Here, we report the effects of widely used antibiotics (clindamycin, ciprofloxacin, amoxicillin, and

  16. Long term effects of prenatal and postnatal airborne PAH exposures on ventilatory lung function of non-asthmatic preadolescent children. Prospective birth cohort study in Krakow.

    Science.gov (United States)

    Jedrychowski, Wieslaw A; Perera, Frederica P; Maugeri, Umberto; Majewska, Renata; Mroz, Elzbieta; Flak, Elzbieta; Camann, David; Sowa, Agata; Jacek, Ryszard

    2015-01-01

    The main goal of the study was to test the hypothesis that prenatal and postnatal exposures to polycyclic aromatic hydrocarbons (PAH) are associated with depressed lung function in non-asthmatic children. The study sample comprises 195 non-asthmatic children of non-smoking mothers, among whom the prenatal PAH exposure was assessed by personal air monitoring in pregnancy. At the age of 3, residential air monitoring was carried out to evaluate the residential PAH exposure indoors and outdoors. At the age of 5 to 8, children were given allergic skin tests for indoor allergens; and between 5 and 9 years lung function testing (FVC, FEV05, FEV1 and FEF25-75) was performed. The effects of prenatal PAH exposure on lung function tests repeated over the follow-up were adjusted in the General Estimated Equation (GEE) model for the relevant covariates. No association between FVC with prenatal PAH exposure was found; however for the FEV1 deficit associated with higher prenatal PAH exposure (above 37 ng/m(3)) amounted to 53 mL (p=0.050) and the deficit of FEF25-75 reached 164 mL (p=0.013). The corresponding deficits related to postnatal residential indoor PAH level (above 42 ng/m(3)) were 59 mL of FEV1 (p=0.028) and 140 mL of FEF25-75 (p=0.031). At the higher residential outdoor PAH level (above 90 ng/m(3)) slightly greater deficit of FEV1 (71 mL, p=0.009) was observed. The results of the study suggest that transplacental exposure to PAH compromises the normal developmental process of respiratory airways and that this effect is compounded by postnatal PAH exposure.

  17. LONG TERM EFFECTS OF PRENATAL AND POSTNATAL AIRBORNE PAH EXPOSURE ON VENTILATORY LUNG FUNCTION OF NON-ASTHMATIC PREADOLESCENT CHILDREN. PROSPECTIVE BIRTH COHORT STUDY IN KRAKOW

    Science.gov (United States)

    Jedrychowski, Wieslaw A.; Perera, Frederica P.; Maugeri, Umberto; Majewska, Renata; Mroz, Elzbieta; Flak, Elzbieta; Camman, David; Sowa, Agata; Jacek, Ryszard

    2014-01-01

    The main goal of the study was to test the hypothesis that prenatal and postnatal exposure to polycyclic aromatic hydrocarbons (PAH) is associated with depressed lung function in non-asthmatic children. The study sample comprises 195 non-asthmatic children of non-smoking mothers, among whom the prenatal PAH exposure was assessed by personal air monitoring in pregnancy. At the age of 3, residential air monitoring was carried out to evaluate the residential PAH exposure indoors and outdoors. At the age of 5 to 8, children were given allergic skin tests for indoor allergens; and between 5–9 years lung function testing (FVC, FEV05, FEV1 and FEF25–75) was performed. The effects of prenatal PAH exposure on lung function tests repeated over the follow-up were adjusted in the General Estimated Equation (GEE) model for the relevant covariates. No association between FVC with prenatal PAH exposure was found; however for the FEV1 deficit associated with higher prenatal PAH exposure (above 37ng/m3) amounted to 53 mL (p = 0.050) and the deficit of FEF25–75 reached 164 mL (p=0.013). The corresponding deficits related to postnatal residential indoor PAH level (above 42 ng/m3) were 59 mL of FEV1 (p=0.028) and 140 mL of FEF25–75 (p=0.031). At the higher residential outdoor PAH level (above 90 ng/m3) slightly greater deficit of FEV1 (71mL, p = 0.009) was observed. The results of the study suggest that transplacental exposure to PAH compromises the normal developmental process of respiratory airways and that this effect is compounded by postnatal PAH exposure. PMID:25300014

  18. Long-term exposure to dieldrin reduces gamma-aminobutyric acid type A and N-methyl-D-aspartate receptor function in primary cultures of mouse cerebellar granule cells.

    Science.gov (United States)

    Babot, Zoila; Vilaró, M Teresa; Suñol, Cristina

    2007-12-01

    The organochlorine pesticide dieldrin is a persistent organic pollutant that accumulates in the fatty tissue of living organisms. In mammals, it antagonizes the GABA(A) receptor, producing convulsions after acute exposure. Although accumulation in human brain has been reported, little is known about the effects of long-term exposure to dieldrin in the nervous system. Homeostatic control of the balance between excitation and inhibition has been reported when neuronal activity is chronically altered. We hypothesized that noncytotoxic concentrations of dieldrin could decrease glutamatergic neurotransmission as a consequence of a prolonged reduction in GABA(A) receptor function. Long-term exposure of primary cerebellar granule cell cultures to 3 microM dieldrin reduced the GABA(A) receptor function to 55% of control, as measured by the GABA-induced (36)Cl(-) uptake. This exposure produced a significant reduction (approximately 35%) of the NMDA-induced increase in [Ca(2+)](i) and of the [(3)H]MK-801 binding, which was not accompanied by a reduction in the NMDA receptor subunit NR1, as determined by Western blot. Consistent with the decreased NMDA receptor function, dieldrin-treated cultures were insensitive to an excitotoxic stimulus induced by exposure to high potassium. In summary, we report that the chronic reduction of GABA(A) receptor function induced by dieldrin decreases the number of functional NMDA receptors, which may be attributable to a mechanism of synaptic scaling. These effects could underlie neural mechanisms involved in cognitive impairment produced by low-level exposure to dieldrin. (c) 2007 Wiley-Liss, Inc.

  19. Assessment of long-term effects of exposure to toluene based on the analysis of selected behavioral responses with particular reference to the ability to trigger behavioral hypersensitivity in rats.

    Science.gov (United States)

    Wiaderna, Dorota; Tomas, Tadeusz

    2002-01-01

    Toluene is a major component of numerous commercial organic solvent formulations. It is often listed among the chemicals capable of producing the organic solvent syndrome and a neurobehavioral hypersensitivity condition. The hypersensitivity condition (continued long-term intensification of some behavioral reactions in response to pharmacological or environmental stressors) is usually associated with the increased tonus of the functional dopaminergic system. The aim of our current research was to determine whether, under conditions of inhalation exposure, toluene can produce long-term behavioral changes or modify the intensity of the behavioral response to apomorphine, a dopaminergic receptor agonist. In our experiment, male rats were exposed to 25, 100 and 250 ppm toluene for 4 weeks (5 days/week, 6h/day). The following behaviors were tested: finding water in a radial maze; open field motor activity, acquiring the conditional response of passive avoidance; sensitivity to a thermal pain stimulus (hot plate test) and changes in this sensitivity caused by stress; and acquiring the conditional response of two-directional active avoidance. The behavioral response to apomorphine, i.e. the increased spontaneous locomotor activity, was assessed on day 10 after the termination of the exposure in the rotary drum test. In the behavioral experiment, significant differences between groups were recorded only for the hot plate test; in the 100 and 250 ppm rats, electric-shock-related anxiety response was stronger than in the control group. In the experiment using pharmacological provocation, the behavioral response to apomorphine in the rats exposed to 100 ppm or 250 ppm toluene was significantly lower. Our results indicate that low concentrations of toluene may produce long-term behavioral changes in rats. However, these changes seem to be linked with reduced rather than increased functional tonus of the dopaminergic system.

  20. Long-term monitoring of radiation exposure of employees in the department of nuclear medicine (Szczecin, Poland) in the years 1991-2007.

    Science.gov (United States)

    Piwowarska-Bilska, H; Birkenfeld, B; Listewnik, M; Zorga, P

    2010-08-01

    Occupational radiation exposure is a hazard that should be avoided or at least minimised. This study aimed to evaluate the radiation exposure of nuclear medicine department employees monitored during the 1991-2007 period, and to investigate the relationship between the annual effective doses of the personnel and the number of radioisotope procedures performed. Overall, 2014 quarterly effective whole-body doses, categorised into six occupational groups, monitored with personal dosemeters, were analysed statistically. There was a wide variation in the average annual doses among the different occupational groups. During the 17 years covered by this study, there was no incidence of a dose exceeding the annual dose limit of 20 mSv. There was a weak correlation between the average annual dose for monitored employees and the number of nuclear medicine procedures performed. Apart from exposure, personal skill in dealing with radioactive substances, compliance with radiation protection rules is an important factor to minimise the effective dose.

  1. High-calcium diet modulates effects of long-term prolactin exposure on the cortical bone calcium content in ovariectomized rats.

    Science.gov (United States)

    Charoenphandhu, Narattaphol; Tudpor, Kukiat; Thongchote, Kanogwun; Saengamnart, Wasana; Puntheeranurak, Supaporn; Krishnamra, Nateetip

    2007-02-01

    High physiological prolactin induced positive calcium balance by stimulating intestinal calcium absorption, reducing renal calcium excretion, and increasing bone calcium deposition in female rats. Although prolactin-induced increase in trabecular bone calcium deposition was absent after ovariectomy, its effects on cortical bones were still controversial. The present investigation, therefore, aimed to study the effect of in vivo long-term high physiological prolactin induced by either anterior pituitary (AP) transplantation or 2.5 mg/kg prolactin injection on cortical bones in ovariectomized rats. Since the presence of prolactin receptors (PRLR) in different bones of normal adult rats has not been reported, we first determined mRNA expression of both short- and long-form PRLRs at the cortical sites (tibia and femur) and trabecular sites (calvaria and vertebrae) by using the RT-PCR. Our results showed the mRNA expression of both PRLR isoforms with predominant long form at all sites. However, high prolactin levels induced by AP transplantation in normal rats did not have any effect on the femoral bone mineral density or bone mineral content. By using (45)Ca kinetic study, 2.5 mg/kg prolactin did not alter bone formation, bone resorption, calcium deposition, and total calcium content in tibia and femur of adult ovariectomized rats. AP transplantation also had no effect on the cortical total calcium content in adult ovariectomized rats. Because previous work showed that the effects of prolactin were age dependent and could be modulated by high-calcium diet, interactions between prolactin and these two parameters were investigated. The results demonstrated that 2.0% wt/wt high-calcium diet significantly increased the tibial total calcium content in 9-wk-old young AP-grafted ovariectomized rats but decreased the tibial total calcium content in 22-wk-old adult rats. As for the vertebrae, the total calcium contents in both young and adult rats were not changed by high

  2. The impact of long-term exposure to space environment on adult mammalian organisms: a study on mouse thyroid and testis.

    Directory of Open Access Journals (Sweden)

    Maria Angela Masini

    Full Text Available Hormonal changes in humans during spaceflight have been demonstrated but the underlying mechanisms are still unknown. To clarify this point thyroid and testis/epididymis, both regulated by anterior pituitary gland, have been analyzed on long-term space-exposed male C57BL/10 mice, either wild type or pleiotrophin transgenic, overexpressing osteoblast stimulating factor-1. Glands were submitted to morphological and functional analysis.In thyroids, volumetric ratios between thyrocytes and colloid were measured. cAMP production in 10(-7M and 10(-8M thyrotropin-treated samples was studied. Thyrotropin receptor and caveolin-1 were quantitized by immunoblotting and localized by immunofluorescence. In space-exposed animals, both basal and thyrotropin-stimulated cAMP production were always higher. Also, the structure of thyroid follicles appeared more organized, while thyrotropin receptor and caveolin-1 were overexpressed. Unlike the control samples, in the space samples thyrotropin receptor and caveolin-1 were both observed at the intracellular junctions, suggesting their interaction in specific cell membrane microdomains.In testes, immunofluorescent reaction for 3β- steroid dehydrogenase was performed and the relative expressions of hormone receptors and interleukin-1β were quantified by RT-PCR. Epididymal sperm number was counted. In space-exposed animals, the presence of 3β and 17β steroid dehydrogenase was reduced. Also, the expression of androgen and follicle stimulating hormone receptors increased while lutenizing hormone receptor levels were not affected. The interleukin 1 β expression was upregulated. The tubular architecture was altered and the sperm cell number was significantly reduced in spaceflight mouse epididymis (approx. -90% vs. laboratory and ground controls, indicating that the space environment may lead to degenerative changes in seminiferous tubules.Space-induced changes of structure and function of thyroid and testis

  3. The impact of long-term exposure to space environment on adult mammalian organisms: a study on mouse thyroid and testis.

    Science.gov (United States)

    Masini, Maria Angela; Albi, Elisabetta; Barmo, Cristina; Bonfiglio, Tommaso; Bruni, Lara; Canesi, Laura; Cataldi, Samuela; Curcio, Francesco; D'Amora, Marta; Ferri, Ivana; Goto, Katsumasa; Kawano, Fuminori; Lazzarini, Remo; Loreti, Elisabetta; Nakai, Naoya; Ohira, Takashi; Ohira, Yoshinobu; Palmero, Silvio; Prato, Paola; Ricci, Franco; Scarabelli, Linda; Shibaguchi, Tsubasa; Spelat, Renza; Strollo, Felice; Ambesi-Impiombato, Francesco Saverio

    2012-01-01

    Hormonal changes in humans during spaceflight have been demonstrated but the underlying mechanisms are still unknown. To clarify this point thyroid and testis/epididymis, both regulated by anterior pituitary gland, have been analyzed on long-term space-exposed male C57BL/10 mice, either wild type or pleiotrophin transgenic, overexpressing osteoblast stimulating factor-1. Glands were submitted to morphological and functional analysis.In thyroids, volumetric ratios between thyrocytes and colloid were measured. cAMP production in 10(-7)M and 10(-8)M thyrotropin-treated samples was studied. Thyrotropin receptor and caveolin-1 were quantitized by immunoblotting and localized by immunofluorescence. In space-exposed animals, both basal and thyrotropin-stimulated cAMP production were always higher. Also, the structure of thyroid follicles appeared more organized, while thyrotropin receptor and caveolin-1 were overexpressed. Unlike the control samples, in the space samples thyrotropin receptor and caveolin-1 were both observed at the intracellular junctions, suggesting their interaction in specific cell membrane microdomains.In testes, immunofluorescent reaction for 3β- steroid dehydrogenase was performed and the relative expressions of hormone receptors and interleukin-1β were quantified by RT-PCR. Epididymal sperm number was counted. In space-exposed animals, the presence of 3β and 17β steroid dehydrogenase was reduced. Also, the expression of androgen and follicle stimulating hormone receptors increased while lutenizing hormone receptor levels were not affected. The interleukin 1 β expression was upregulated. The tubular architecture was altered and the sperm cell number was significantly reduced in spaceflight mouse epididymis (approx. -90% vs. laboratory and ground controls), indicating that the space environment may lead to degenerative changes in seminiferous tubules.Space-induced changes of structure and function of thyroid and testis/epididymis could be

  4. Intermittent Exposure to Social Defeat and Open-field Test in Rats : Acute and Long-term Effects on ECG, Body Temperature and Physical Activity

    NARCIS (Netherlands)

    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

  5. Review of the Institute of Medicine Report: Long-term Health Consequences of Exposure to Burn Pits in Iraq and Afghanistan

    Science.gov (United States)

    2012-01-01

    lupus, and rheumatoid arthritis . Continued follow-up of these cohorts will provide information regarding de- ployment related exposures in addition to...study evaluated birth outcomes in in- fants whose mothers and fathers had been exposed be- fore and during pregnancy , chronic multisystem illness

  6. Long-term exposure to 835 MHz RF-EMF induces hyperactivity, autophagy and demyelination in the cortical neurons of mice

    Science.gov (United States)

    Kim, Ju Hwan; Yu, Da-Hyeon; Huh, Yang Hoon; Lee, Eun Ho; Kim, Hyung-Gun; Kim, Hak Rim

    2017-01-01

    Radiofrequency electromagnetic field (RF-EMF) is used globally in conjunction with mobile communications. There are public concerns of the perceived deleterious biological consequences of RF-EMF exposure. This study assessed neuronal effects of RF-EMF on the cerebral cortex of the mouse brain as a proxy for cranial exposure during mobile phone use. C57BL/6 mice were exposed to 835 MHz RF-EMF at a specific absorption rate (SAR) of 4.0 W/kg for 5 hours/day during 12 weeks. The aim was to examine activation of autophagy pathway in the cerebral cortex, a brain region that is located relatively externally. Induction of autophagy genes and production of proteins including LC3B-II and Beclin1 were increased and accumulation of autolysosome was observed in neuronal cell bodies. However, proapoptotic factor Bax was down-regulted in the cerebral cortex. Importantly, we found that RF-EMF exposure led to myelin sheath damage and mice displayed hyperactivity-like behaviour. The data suggest that autophagy may act as a protective pathway for the neuronal cell bodies in the cerebral cortex during radiofrequency exposure. The observations that neuronal cell bodies remained structurally stable but demyelination was induced in cortical neurons following prolonged RF-EMF suggests a potential cause of neurological or neurobehavioural disorders. PMID:28106136

  7. Intermittent Exposure to Social Defeat and Open-field Test in Rats : Acute and Long-term Effects on ECG, Body Temperature and Physical Activity

    NARCIS (Netherlands)

    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

  8. Experimental Transmission of Karshi (Mammalian Tick-Borne Flavivirus Group Virus by Ornithodoros Ticks >2,900 Days after Initial Virus Exposure Supports the Role of Soft Ticks as a Long-Term Maintenance Mechanism for Certain Flaviviruses.

    Directory of Open Access Journals (Sweden)

    Michael J Turell

    Full Text Available Members of the mammalian tick-borne flavivirus group, including tick-borne encephalitis virus, are responsible for at least 10,000 clinical cases of tick-borne encephalitis each year. To attempt to explain the long-term maintenance of members of this group, we followed Ornithodoros parkeri, O. sonrai, and O. tartakovskyi for >2,900 days after they had been exposed to Karshi virus, a member of the mammalian tick-borne flavivirus group.Ticks were exposed to Karshi virus either by allowing them to feed on viremic suckling mice or by intracoelomic inoculation. The ticks were then allowed to feed individually on suckling mice after various periods of extrinsic incubation to determine their ability to transmit virus by bite and to determine how long the ticks would remain infectious. The ticks remained efficient vectors of Karshi virus, even when tested >2,900 d after their initial exposure to virus, including those ticks exposed to Karshi virus either orally or by inoculation.Ornithodoros spp. ticks were able to transmit Karshi virus for >2,900 days (nearly 8 years after a single exposure to a viremic mouse. Therefore, these ticks may serve as a long-term maintenance mechanism for Karshi virus and potentially other members of the mammalian tick-borne flavivirus group.

  9. Effects of long-term low-level radiation exposure after the Chernobyl catastrophe on immunoglobulins in children residing in contaminated areas: prospective and cross-sectional studies.

    Science.gov (United States)

    McMahon, Daria M; Vdovenko, Vitaliy Y; Karmaus, Wilfried; Kondrashova, Valentina; Svendsen, Erik; Litvinetz, Oksana M; Stepanova, Yevgenia I

    2014-05-10

    After the Chernobyl nuclear incident in 1986, children in the Narodichesky region, located 80 km west of the Chernobyl Power Plant, were exposed to 137Cesium (137Cs). Little is known about the effects of chronic low-level radiation on humoral immune responses in children residing in contaminated areas. In four different approaches we investigated the effect of residential 137Cs exposure on immunoglobulins A, G, M, and specific immunoglobulin E in children. In a dynamic cohort (1993-1998) we included 617 children providing 2,407 repeated measurements; 421 and 523 children in two cross-sectional samples (1997-1998 and 2008-2010, respectively); and 25 participants in a small longitudinal cohort (1997-2010). All medical exams, blood collections, and analyses were conducted by the same team. We used mixed linear models to analyze repeated measurements in cohorts and general linear regression models for cross-sectional studies. Residential soil contamination in 2008 was highly correlated with the individual body burden of 137Cs. Serum IgG and IgM concentrations increased between 1993 and 1998. Children with higher 137Cs soil exposure had lower serum IgG levels, which, however, increased in the small cohort assessed between 1997 and 2010. Children within the fourth quintile of 137Cs soil exposure (266-310 kBq/m2) had higher IgM serum concentrations between 1993 and 1998 but these declined between 1997 and 2010. IgA remained stable with median 137Cs exposures related to higher IgA levels, which was corroborated in the cross-sectional study of 2008-2010. Specific IgE against indoor allergens was detected less often in children with higher 137Cs exposure. Our findings show radiation-related alterations of immunoglobulins which by themselves do not constitute adverse health effects. Further investigations are necessary to understand how these changes affect health status.

  10. Risk assessment for changes in the metabolic profile and body weights of pre-pubertal gilts during long-term monotonic exposure to low doses of zearalenone (ZEN).

    Science.gov (United States)

    Gajęcka, Magdalena; Tarasiuk, Michał; Zielonka, Łukasz; Dąbrowski, Michał; Gajęcki, Maciej

    2016-12-01

    The aim of the study was to examine whether the process of exposure to low doses of ZEN generates changes in the hematological and biochemical image of blood serum. During the experiment, pre-pubertal gilts (up to 25kg) were administered per os ZEN at a dose of 40μg/kg BW (Group E, n=18) or placebo (Group C, n=21) on a daily basis for 42days. Blood samples for investigation were collected seven times at intervals of one week. In the experimental groups, slight but statistically significant changes in the values of selected biochemical blood indices such as glucose, ALT, Pin, total protein and Fe, or in hematological indices such as RBC, MCV, PLT, WBC, basophils, eosinophils and monocytes were observed. Based on statistical analysis between the groups, differences in the values of WBC, basophils, peroxidase negative cells, Hb, Ht, MCV, HDW, glucose, ALT, AP, total protein, iron or potassium were found. In Group E, decreasing trends in the values of PLT and glucose, and increasing trends in the values of total protein, Pin, Na and Cl were found. The described situations occurred during the last three weeks of exposure. Low levels of exposure to ZEN lead to completely different changes in the metabolic profile than those resulting from higher doses of the toxin. The stimulatory effect of mycotoxins, observed in initial stages of exposure, is eliminated when the compensatory response and adaptive mechanisms are triggered, and due to excessive loss of energy, which may point to more efficient feed utilization and/or detoxification processes. The values of body weight gain obtained in Group E were monotonically higher in four out of the six investigated weeks of exposure. The above changes were accompanied by a decrease in glucose concentrations and higher total protein levels (a rising tendency), which could have affected the rate of body weight gain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Effects of Long-Term Exposure to 60 GHz Millimeter-Wavelength Radiation on the Genotoxicity and Heat Shock Protein (Hsp Expression of Cells Derived from Human Eye

    Directory of Open Access Journals (Sweden)

    Shin Koyama

    2016-08-01

    Full Text Available Human corneal epithelial (HCE-T and human lens epithelial (SRA01/04 cells derived from the human eye were exposed to 60 gigahertz (GHz millimeter-wavelength radiation for 24 h. There was no statistically significant increase in the micronucleus (MN frequency in cells exposed to 60 GHz millimeter-wavelength radiation at 1 mW/cm2 compared with sham-exposed controls and incubator controls. The MN frequency of cells treated with bleomycin for 1 h provided positive controls. The comet assay, used to detect DNA strand breaks, and heat shock protein (Hsp expression also showed no statistically significant effects of exposure. These results indicate that exposure to millimeter-wavelength radiation has no effect on genotoxicity in human eye cells.

  12. In vitro assessment of DNA damage after short- and long-term exposure to benzo(a)pyrene using RAPD and the RTG-2 fish cell line.

    Science.gov (United States)

    Castaño, Argelia; Becerril, Concepción

    2004-08-18

    Genotoxins present in the aquatic environment are often associated with the decline or disappearance of many wild populations. The hazard assessment of chemicals requires sensitive and specific tests to study the genotoxic effects in order to establish the maximum allowable chemical concentrations prior to the release to the environment. We have previously shown that an established fish cell line (RTG-2) together with the random amplified polymorphic DNA (RAPD) technique, can be used to detect alterations in the DNA caused by direct acting genotoxins. The current study takes this a step further and examines in the same system the effect of a pro-mutagen benzo(a)pyrene (B(a)P) at different concentrations (0.05, 0.1, and 0.5 microg/ml) and at different exposure periods (1, 2, 3, 15, and 30 days). After comparing DNA fingerprints from control and exposed cells, both qualitative and quantitative analysis show an increase in the instability in the DNA fingerprint of exposed cells over a time- and concentration-dependent manner. At the higher concentration (0.5 microg/ml) three out the four primers showed altered bands after 1 day of exposure, while after 3 days all used primers showed an altered pattern. At the lower concentration of B(a)P (0.05 microg/ml) the appearance of new bands was observed with a 100% level of reproducibility after 30 days of exposure suggesting an inheritance of the altered DNA. We conclude that this in vitro system is useful to evaluate genotoxic effects, both after acute and chronic exposures and of direct and non-direct acting genotoxins. Cultured cells can be considered as genetically homogenous populations. Therefore, in vitro systems permits us to undertake mechanistic studies avoiding the interference of polymorphisms inherent in the in vivo systems. Furthermore, the RTG-2 fish cell line combined with a RAPD assay could be used in studies of hazard identification in risk assessment protocols of chemicals.

  13. Cytokines related to three major types of cell-mediated immunity in short- and long-term exposures to lead compounds.

    Science.gov (United States)

    Dobrakowski, Michał; Boroń, Marta; Czuba, Zenon P; Kasperczyk, Aleksandra; Machoń-Grecka, Anna; Kasperczyk, Sławomir

    2016-11-01

    Many investigators have posited on the significant influence of lead on the immune system function. However, available data on this topic are not conclusive. Therefore, a study was undertaken to examine associations between lead exposure and levels of cytokines related to the T-helper (TH)-1, TH2, and TH17 types of immune response in humans. For these analyses, three population groups were examined: the first consisted of male workers exposed to lead for a short period of time (36-44 days); the second included male workers chronically exposed to lead (13 ± 10 years); and a control group that was composed of male administrative workers with blood lead levels (BLL) lead (compared to baseline). However, the levels of all of these cytokines were significantly higher in workers chronically exposed to lead than in the controls by 82%, 32%, 81%, 22%, 70%, 42%, and 17% (IFNγ, IL-2, IL-12, IL-4, IL-5, IL-13, IL-17A, respectively). From these studies, we conclude that in humans, a short-term exposure to lead does not affect levels of cytokines related to the TH1-, TH2-, and TH17-mediated immune responses, while chronic exposure modifies their levels. Taken together, these modifications do not evidence an ability of lead to promote specifically one type of immune response in an exposed host.

  14. The Prediction of Long-Term Coating Performance from Short-Term Electrochemical Data. Part 2; Comparison of Electrochemical Data to Field Exposure Results for Coatings on Steel

    Science.gov (United States)

    Contu, F.; Taylor, S. R.; Calle, L. M.; Hintze, P. E.; Curran, J. P.; Li, W.

    2009-01-01

    The pace of coatings development is limited by the time required to assess their corrosion protection properties. This study takes a step f orward from Part I in that it correlates the corrosion performance of organic coatings assessed by a series of short-term electrochemical measurement with 18-month beachside exposure results of duplicate pan els. A series of 19 coating systems on A36 steel substrates were test ed in a completely blind study using the damage tolerance test (DTT). In the DTT, a through-film pinhole defect is created, and the electro chemical characteristics of the defect are then monitored over the ne xt 4 to 7 days while immersed in 0.SM NaCl. The open circuit potentia l, anodic potentiostatic polarization tests and electrochemical imped ance spectroscopy were used to study the corrosion behavior of the co ating systems. The beachside exposure tests were conducted at the Ken nedy Space Center according to ASTM D610-01. It was found that for 79 % of the coatings systems examined, the 18 month beachside exposure r esults could be predicted by two independent laboratory tests obtained within 7 days.

  15. An in vivo animal study assessing long-term changes in hypothalamic cytokines following perinatal exposure to a chemical mixture based on Arctic maternal body burden

    Directory of Open Access Journals (Sweden)

    Li Nanqin

    2011-07-01

    Full Text Available Abstract Background The geographic distribution of environmental toxins is generally not uniform, with certain northern regions showing a particularly high concentration of pesticides, heavy metals and persistent organic pollutants. For instance, Northern Canadians are exposed to high levels of persistent organic pollutants like polychlorinated biphenyls (PCB, organochlorine pesticides (OCs and methylmercury (MeHg, primarily through country foods. Previous studies have reported associations between neuronal pathology and exposure to such toxins. The present investigation assessed whether perinatal exposure (gestation and lactation of rats to a chemical mixture (27 constituents comprised of PCBs, OCs and MeHg based on Arctic maternal exposure profiles at concentrations near human exposure levels, would affect brain levels of several inflammatory cytokines Methods Rats were dosed during gestation and lactation and cytokine levels were measured in the brains of offspring at five months of age. Hypothalamic cytokine protein levels were measured with a suspension-based array system and differences were determined using ANOVA and post hoc statistical tests. Results The early life PCB treatment alone significantly elevated hypothalamic interleukin-6 (IL-6 levels in rats at five months of age to a degree comparable to that of the entire chemical mixture. Similarly, the full mixture (and to a lesser degree PCBs alone elevated levels of the pro-inflammatory cytokine, IL-1b, as well as the anti-inflammatory cytokine, IL-10. The full mixture of chemicals also moderately increased (in an additive fashion hypothalamic levels of the pro-inflammatory cytokines, IL-12 and tumor necrosis factor (TNF-α. Challenge with bacterial endotoxin at adulthood generally increased hypothalamic levels to such a degree that differences between the perinatally treated chemical groups were no longer detectable. Conclusions These data suggest that exposure at critical

  16. Characteristics of noise exposure during solitary trumpet playing: immediate impact on distortion-product otoacoustic emissions and long-term implications for hearing.

    Science.gov (United States)

    Poissant, Sarah F; Freyman, Richard L; MacDonald, Allison J; Nunes, Heather A

    2012-01-01

    The objectives of this investigation were to quantify noise exposures generated during a 1 hr trumpet practice session and to determine whether distortion-product otoacoustic emissions (DPOAEs) are affected by such exposure, to describe the distribution of intensity levels and temporal characteristics of noise produced by trumpet practice, and to determine the effect of earplug use on generated noise levels and DPOAEs. In experiment 1, eight college-age trumpeters underwent an otoscopic inspection, tympanometry, and pure-tone threshold testing. Using a Grason-Stadler 60 DPOAE system, DPOAEs were recorded just before a 1 hr practice session, at 2 min after the practice session, 4 min after the session, and at 4 min intervals thereafter for a total period of 1 hr. A Hewlett-Packard 3569A Real-Time Frequency Analyzer was used to integrate noise levels to assess the overall level of exposure averaged over the course of the hour. In experiment 2, seven different trumpeters participated in two data-collection sessions. The main difference between the sessions was that subjects wore E.A.R. earplugs during session 2. All other design parameters were similar to those of experiment 1. Noise levels generated during the practice sessions resulted in average Leqs of 95.96, 96.6, and 96.43 dB SPL. A sound-distribution analysis revealed that noise levels exceeded 85 dB for an average of 43.73 min per session. Mean Leq values did not change when subjects wore earplugs (96.6 dB SPL versus 96.43 dB SPL.) Predictions (ISO 1999) of the increased risk of hearing loss that trumpeters would experience at 40, 50, and 60 years of age were made and indicated that trumpeters are at a significantly increased risk of hearing loss over that contributable to age alone. This increased risk is apparent with as little as 1 hr of exposure per day and suggests that 60-year-old male and female musicians exposed to trumpet noise for 4 hr per day for 40 years would be 85% and 300%, respectively, more

  17. Atrazine is primarily responsible for the toxicity of long-term exposure to a combination of atrazine and inorganic arsenic in the nigrostriatal system of the albino rat.

    Science.gov (United States)

    Bardullas, Ulises; Giordano, Magda; Rodríguez, Verónica Mireya

    2013-01-01

    Chronic and simultaneous exposure to a variety of chemicals present in the environment is an unavoidable fact. However, given the complexity of studying chemical mixtures, most toxicological studies have focused on the effects of short-term exposure to single substances. The aim of this study was to evaluate the effects on the nigrostriatal system of the chronic, simultaneous exposure to two widely distributed substances that have been identified as potential dopaminergic system toxicants, inorganic arsenic (iAs) and atrazine (ATR). Six groups of rats were treated daily for one year with atrazine (10mg ATR/kg), inorganic arsenic (0.5 or 50mgiAs/L of drinking water), or a combination of ATR+0.5mgiAs/L or ATR+50mgiAs/L. The 50mgiAs/L group showed locomotor hypoactivity, while all treatments decreased motor coordination in contrast no effects of treatment were found on the place and response learning tasks. Regarding markers for liver and muscle damage, there were no differences between groups in creatine kinase (CK) or aspartate transaminase (AST) activities, while decreases in lactate dehydrogenase (LDH) levels were found in some exposed groups. The striatal DA content was significantly reduced in ATR, 0.5mgiAs/L, ATR+0.5mgiAs/L, and ATR+50mgiAs/L groups, in comparison to the control group. The number of mesencephalic tyrosine hydroxylase positive cells decreased in the ATR and ATR+0.5mgiAs/L groups compared to the control. In contrast, immunoreactivity to cytochrome oxidase was reduced compared to the control in all treated groups, except for the group treated with 0.5iAsmg alone. Our results indicate that ATR has deleterious effects on dopaminergic neurons and that the combination of ATR and iAs does not exacerbate these effects.

  18. Identification and quantification of phytochelatins in roots of rice to long-term exposure: evidence of individual role on arsenic accumulation and translocation.

    Science.gov (United States)

    Batista, Bruno Lemos; Nigar, Meher; Mestrot, Adrien; Rocha, Bruno Alves; Barbosa Júnior, Fernando; Price, Adam H; Raab, Andrea; Feldmann, Jörg

    2014-04-01

    Rice has the predilection to take up arsenic in the form of methylated arsenic (o-As) and inorganic arsenic species (i-As). Plants defend themselves using i-As efflux systems and the production of phytochelatins (PCs) to complex i-As. Our study focused on the identification and quantification of phytochelatins by HPLC-ICP-MS/ESI-MS, relating them to the several variables linked to As exposure. GSH, 11 PCs, and As-PC complexes from the roots of six rice cultivars (Italica Carolina, Dom Sofid, 9524, Kitrana 508, YRL-1, and Lemont) exposed to low and high levels of i-As were compared with total, i-As, and o-As in roots, shoots, and grains. Only Dom Sofid, Kitrana 508, and 9524 were found to produce higher levels of PCs even when exposed to low levels of As. PCs were only correlated to i-As in the roots (r=0.884, P <0.001). However, significant negative correlations to As transfer factors (TF) roots-grains (r= -0.739, P <0.05) and shoots-grains (r= -0.541, P <0.05), suggested that these peptides help in trapping i-As but not o-As in the roots, reducing grains' i-As. Italica Carolina reduced i-As in grains after high exposure, where some specific PCs had a special role in this reduction. In Lemont, exposure to elevated levels of i-As did not result in higher i-As levels in the grains and there were no significant increases in PCs or thiols. Finally, the high production of PCs in Kitrana 508 and Dom Sofid in response to high As treatment did not relate to a reduction of i-As in grains, suggesting that other mechanisms such as As-PC release and transport seems to be important in determining grain As in these cultivars.

  19. Effects of long-term dietary exposure to organohalogen contaminants on vitamin and hormonestatus in the Greenland Sledge dog (Canis familiaris)

    DEFF Research Database (Denmark)

    Kirkegaard, Maja

    conducted on Greenland sledge dogs. This aimed at exploring how a diet rich in OHCs affects vitamin and hormone status in Arctic top predator mammals. The dogs were supplemented with fat containing high (exposed group: minke whale blubber) or low (control group: porcine fat) amounts of OHCs, polyunsaturated...... (6 to 18 months of age), and also for Free and Total T3 and T4, when sampled between 10 to 18 months of age. The present thesis supports the notion that wild mammals at the top of Arctic food chains are suffering from chronic non-lethal, subclinical symptoms due to exposure to complex environmental...

  20. Same Exposure but Two Radically Different Responses to Antibiotics: Resilience of the Salivary Microbiome versus Long-Term Microbial Shifts in Feces.

    Science.gov (United States)

    Zaura, Egija; Brandt, Bernd W; Teixeira de Mattos, M Joost; Buijs, Mark J; Caspers, Martien P M; Rashid, Mamun-Ur; Weintraub, Andrej; Nord, Carl Erik; Savell, Ann; Hu, Yanmin; Coates, Antony R; Hubank, Mike; Spratt, David A; Wilson, Michael; Keijser, Bart J F; Crielaard, Wim

    2015-11-10

    Due to the spread of resistance, antibiotic exposure receives increasing attention. Ecological consequences for the different niches of individual microbiomes are, however, largely ignored. Here, we report the effects of widely used antibiotics (clindamycin, ciprofloxacin, amoxicillin, and minocycline) with different modes of action on the ecology of both the gut and the oral microbiomes in 66 healthy adults from the United Kingdom and Sweden in a two-center randomized placebo-controlled clinical trial. Feces and saliva were collected at baseline, immediately after exposure, and 1, 2, 4, and 12 months after administration of antibiotics or placebo. Sequences of 16S rRNA gene amplicons from all samples and metagenomic shotgun sequences from selected baseline and post-antibiotic-treatment sample pairs were analyzed. Additionally, metagenomic predictions based on 16S rRNA gene amplicon data were performed using PICRUSt. The salivary microbiome was found to be significantly more robust, whereas the antibiotics negatively affected the fecal microbiome: in particular, health-associated butyrate-producing species became strongly underrepresented. Additionally, exposure to different antibiotics enriched genes associated with antibiotic resistance. In conclusion, healthy individuals, exposed to a single antibiotic treatment, undergo considerable microbial shifts and enrichment in antibiotic resistance in their feces, while their salivary microbiome composition remains unexpectedly stable. The health-related consequences for the gut microbiome should increase the awareness of the individual risks involved with antibiotic use, especially in a (diseased) population with an already dysregulated microbiome. On the other hand, understanding the mechanisms behind the resilience of the oral microbiome toward ecological collapse might prove useful in combating microbial dysbiosis elsewhere in the body. Many health care professionals use antibiotic prophylaxis strategies to prevent

  1. Influence of LBE long term exposure and simultaneous fast neutron irradiation on the mechanical properties of T91 and 316L

    Energy Technology Data Exchange (ETDEWEB)

    Stergar, E., E-mail: estergar@sckcen.be [SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Eremin, S.G. [RIAR, Research Institute of Atomic Reactors, Dimitrovgrad (Russian Federation); Gavrilov, S.; Lambrecht, M. [SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Makarov, O.; Iakovlev, V. [RIAR, Research Institute of Atomic Reactors, Dimitrovgrad (Russian Federation)

    2016-05-15

    The LEXUR–II–LBE irradiation campaign was conducted from 2011 to 2012 and was aimed to investigate the combined influence of irradiation and LBE environment. In this irradiation campaign tensile test samples, pressurized tubes and corrosion samples were irradiated in LBE filled capsules. To separate the effect of exposure to LBE and neutron irradiation a parallel furnace experiment where the samples were exposed to LBE at the irradiation temperature for the corresponding time was conducted. Here we report results of the first extracted capsule which was irradiated about 6 months and dismantled after a cooling phase to decrease activity. The results of SSRT tests for irradiated T91 show that the exposure to LBE at 350 °C for a long time leads to the appearance of liquid metal embrittlement without any pre-treatment which is usually necessary to promote LME. Irradiation increases the effect of LME on the ductility of T91. In contrast to the findings for T91 the gained results also show that tensile tests on irradiated austenitic stainless steel 316L show no influence of LBE environment on the tensile properties.

  2. The respiratory burst activity and expression of catalase in white shrimp, Litopenaeus vannamei, during long-term exposure to pH stress.

    Science.gov (United States)

    Wang, Wei-Na; Li, Bao-Sheng; Liu, Jin-Jian; Shi, Lei; Alam, M J; Su, Shi-Ju