WorldWideScience

Sample records for sunlight exposure induces

  1. Quantification of ultraviolet radiation-induced DNA damage in the urine of Swedish adults and children following exposure to sunlight

    OpenAIRE

    Liljendahl, Tove Sandberg; Kotova, Natalia; Segerbäck, Dan

    2012-01-01

    DNA damage following exposure to ultraviolet radiation (UVR) is important in skin cancer development. The predominant photoproduct, cyclobutane thymine dimer (T=T), is repaired and excreted in the urine, where it provides a biomarker of exposure. To quantify urinary T=T levels after recreational sunlight exposure in adults and children. Average UVR doses were measured with personal dosimeters. Urinary T=T was analysed with (32)P-postlabelling. ResuLTS: Background levels of T=T increased...

  2. Ultra-accelerated natural sunlight exposure testing

    Science.gov (United States)

    Jorgensen, Gary J.; Bingham, Carl; Goggin, Rita; Lewandowski, Allan A.; Netter, Judy C.

    2000-06-13

    Process and apparatus for providing ultra accelerated natural sunlight exposure testing of samples under controlled weathering without introducing unrealistic failure mechanisms in exposed materials and without breaking reciprocity relationships between flux exposure levels and cumulative dose that includes multiple concurrent levels of temperature and relative humidity at high levels of natural sunlight comprising: a) concentrating solar flux uniformly; b) directing the controlled uniform sunlight onto sample materials in a chamber enclosing multiple concurrent levels of temperature and relative humidity to allow the sample materials to be subjected to accelerated irradiance exposure factors for a sufficient period of time in days to provide a corresponding time of about at least a years worth of representative weathering of the sample materials.

  3. PRKCZ methylation is associated with sunlight exposure in a North American but not a Mediterranean population

    Science.gov (United States)

    Sunlight exposure has been shown to alter DNA methylation patterns across several human cell-types, including T-lymphocytes. Since epigenetic changes establish gene expression profiles, changes in DNA methylation induced by sunlight exposure warrant investigation. The purpose of this study was to as...

  4. Can Skin Exposure to Sunlight Prevent Liver Inflammation?

    Directory of Open Access Journals (Sweden)

    Shelley Gorman

    2015-05-01

    Full Text Available Liver inflammation contributes towards the pathology of non-alcoholic fatty liver disease (NAFLD. Here we discuss how skin exposure to sunlight may suppress liver inflammation and the severity of NAFLD. Following exposure to sunlight-derived ultraviolet radiation (UVR, the skin releases anti-inflammatory mediators such as vitamin D and nitric oxide. Animal modeling studies suggest that exposure to UVR can prevent the development of NAFLD. Association studies also support a negative link between circulating 25-hydroxyvitamin D and NAFLD incidence or severity. Clinical trials are in their infancy and are yet to demonstrate a clear beneficial effect of vitamin D supplementation. There are a number of potentially interdependent mechanisms whereby vitamin D could dampen liver inflammation, by inhibiting hepatocyte apoptosis and liver fibrosis, modulating the gut microbiome and through altered production and transport of bile acids. While there has been a focus on vitamin D, other mediators induced by sun exposure, such as nitric oxide may also play important roles in curtailing liver inflammation.

  5. Effects of Sunlight Exposure on the Quality Parameters of Bottled ...

    African Journals Online (AJOL)

    PROF HORSFALL

    microbial population (total coliform) of the bottled water with increasing exposure to sunlight was observed. ... safe drinking water which has led to the tremendous ... degradation under high temperature (Bach et al., ..... Solar and photocatalytic.

  6. Ultra-Accelerated Natural Sunlight Exposure Testing Facilities

    Science.gov (United States)

    Lewandowski, Allan A.; Jorgensen, Gary J.

    2004-11-23

    A multi-faceted concentrator apparatus for providing ultra-accelerated natural sunlight exposure testing for sample materials under controlled weathering conditions comprising: facets that receive incident natural sunlight, transmits VIS/NIR and reflects UV/VIS onto a secondary reflector that delivers a uniform flux of UV/VIS onto a sample exposure plane located near a center of a facet array in a chamber that provide concurrent levels of temperature and/or relative humidity at high levels of up to 100.times. of natural sunlight that allow sample materials to be subjected to accelerated irradiance exposure factors for a significant period of time of about 3 to 10 days to provide a corresponding time of about at least a years worth representative weathering of sample materials.

  7. Investigation of sunlight-induced deterioration of aroma of pummelo (Citrus maxima) essential oil.

    Science.gov (United States)

    Sun, Hao; Ni, Hui; Yang, Yuanfan; Wu, Ling; Cai, Hui-nong; Xiao, An-feng; Chen, Feng

    2014-12-10

    Deterioration of aromas of pummelo essential oil (EO) induced by sunlight was compared to those induced by heat and oxygen exposure using the techniques of sensory evaluation and GC-MS analysis. The sunlight-exposed EO was found to possess an oily off-flavor odor, which was significantly different from its counterparts induced by oxygen and heat. The strong oily note of the sunlight-exposed EO was attributed to the existence of linalool oxides and limonene oxides, as well as the lack of neral and geranial, for which UV sunlight was revealed to be the critical contributor causing the chemical reactions for the aroma changes. The results demonstrated that UV sunlight could significantly affect the aroma of the pummelo EO, providing valuable information that will benefit the production and storage of EO-based aromatic products.

  8. Dietary calcium intake and sunlight exposure among children aged ...

    African Journals Online (AJOL)

    Nutritional rickets can be caused by either or both calcium and vitamin D deficiencies, and can frequently occur in Africa. In Ethiopia, limited evidence exists regarding the calcium intake of children and their sunlight exposure practices. The purpose of this study was to assess information regarding dietary calcium intake and ...

  9. Sunlight suppressing rejection of 280- to 320-nm UV-radiation-induced skin tumors in mice

    International Nuclear Information System (INIS)

    Morison, W.L.; Kelley, S.P.

    1985-01-01

    Repeated exposure of female C3H/HeNCR- mice to sunlight prevented the normal immunologic rejection of a UV-induced tumor. This systemic immunologic alteration was transferred to syngeneic lethally X-irradiated animals with lymphoid cells from mice exposed to sunlight. The lymphoid cells also were able to suppress the capacity of lymphoid cells from normal animals to reject a UV-induced tumor. The 295- to 320-nm wave band appeared to be responsible for this immunosuppressive effect of sunlight because suppression was prevented by filtration of the radiation through Mylar and by application of a sunscreen containing para-aminobenzoic acid. These observations may have importance in understanding the pathogenesis of sunlight-induced skin cancer in humans

  10. Sunlight-induced DNA damage in human mononuclear cells

    DEFF Research Database (Denmark)

    Møller, Peter; Wallin, Hakan; Holst, Erik

    2002-01-01

    of sunlight was comparable to the interindividual variation, indicating that sunlight exposure and the individual's background were the two most important determinants for the basal level of DNA damage. Influence of other lifestyle factors such as exercise, intake of foods, infections, and age could......In this study of 301 blood samples from 21 subjects, we found markedly higher levels of DNA damage (nonpyrimidine dimer types) in the summer than in the winter detected by single-cell gel electrophoresis. The level of DNA damage was influenced by the average daily influx of sunlight ... to blood sampling. The 3 and 6 day periods before sampling influenced DNA damage the most. The importance of sunlight was further emphasized by a positive association of the DNA damage level to the amount of time the subjects had spent in the sun over a 3 day period prior to the sampling. The effect...

  11. The effects of sunlight exposure on the neutron response of CN-85 track detector

    International Nuclear Information System (INIS)

    Ahmad, N.; Mirza, N.M.; Mirza, S.K.; Tufail, M.

    1996-01-01

    The effect of sunlight exposure on the neutron response of CN-85 track detectors has been studied. It has been observed that the response during the first 28 days of sunlight exposure is slightly enhanced (10%) and then deceases continuously with increase in the sunlight exposure. After 84 days of sunlight exposure the response of the exposed detector relative to an unexposed detector is only 22%. It is also observed that the response can not be maintained by wrapping the CN-85 etch track detectors in typewriter black carbon papers if they are exposed to sunlight. (author)

  12. Sunlight exposure and sun sensitivity associated with disability progression in multiple sclerosis

    NARCIS (Netherlands)

    D'hooghe, M. B.; Haentjens, P.; Nagels, G.; Garmyn, M.; De Keyser, J.

    Background: Sunlight and vitamin D have been inversely associated with the risk of multiple sclerosis (MS). Objective: We investigated sunlight exposure and sun sensitivity in relation to disability progression in MS. Methods: We conducted a survey among persons with MS, registered by the Flemish MS

  13. Toxicological impact of cadmium-based quantum dots towards aquatic biota: Effect of natural sunlight exposure

    Energy Technology Data Exchange (ETDEWEB)

    Silva, B.F. [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Andreani, T. [Centro de Investigação em Química da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CITAB − Centre for Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, UTAD, Vila Real (Portugal); Gavina, A., E-mail: anacsgavina@gmail.com [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Vieira, M.N. [Department of Biology, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Pereira, C.M. [Centro de Investigação em Química da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); Rocha-Santos, T. [Department of Chemistry and Centre for Environmental and Marine Studies (CESAM), University of Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); and others

    2016-07-15

    Highlights: • Under sunlight exposure, all QDs form particle aggregates in the different media. • CdSeS/ZnS QDs showed lower toxic effects to V. fischeri before sunlight exposure. • Sunlight exposure decreased the toxicity of CdS 480 in all organisms. • Sunlight exposure increased the toxicity of CdS 380 QDs for D. magna. • Shell of QDs seemed to make them less harmful to aquatic organisms. - Abstract: Cadmium-based quantum dots (QDs) are increasingly applied in existent and emerging technologies, especially in biological applications due to their exceptional photophysical and functionalization properties. However, they are very toxic compounds due to the high reactive and toxic cadmium core. The present study aimed to determine the toxicity of three different QDs (CdS 380, CdS 480 and CdSeS/ZnS) before and after the exposure of suspensions to sunlight, in order to assess the effect of environmentally relevant irradiation levels in their toxicity, which will act after their release to the environment. Therefore, a battery of ecotoxicological tests was performed with organisms that cover different functional and trophic levels, such as Vibrio fischeri, Raphidocelis subcapitata, Chlorella vulgaris and Daphnia magna. The results showed that core-shell type QDs showed lower toxic effects to V. fischeri in comparison to core type QDs before sunlight exposure. However, after sunlight exposure, there was a decrease of CdS 380 and CdS 480 QD toxicity to bacterium. Also, after sunlight exposure, an effective decrease of CdSeS/ZnS and CdS 480 toxicity for D. magna and R. subcapitata, and an evident increase in CdS 380 QD toxicity, at least for D. magna, were observed. The results of this study suggest that sunlight exposure has an effect in the aggregation and precipitation reactions of larger QDs, causing the degradation of functional groups and formation of larger bulks which may be less prone to photo-oxidation due to their diminished surface area. The same

  14. Water balance of goats in Jeneponto - South Sulawesi under sunlight exposure and water restriction

    Directory of Open Access Journals (Sweden)

    Djoni Prawira Rahardja

    2007-10-01

    Full Text Available Water balance of 5 does of Kacang goat of Jeneponto was studied under the condition of sunlight exposure and water restriction. The study was conducted in dry season with 4 consecutive treatments of 10 d with 4-5 d of adjustment period between two consecutive treatments: (1 indoor and unrestricted water; (2 indoor and restricted water; (3 10 h outdoor–and unrestricted water; (4 10 h outdoor – restricted water. The maximum air temperature of outdoor was 39.3OC, and it was 30OC in the indoor environment. In all treatments, the animals were placed in the individual crates. The plasma volume of the goats was higher under sunlight exposure, but it decreased by water restriction, while hematocrite value indicated a reverse responses. Sunlight exposure did not significantly decrease the intake and digestion of organic matter, but water restriction affected significantly and this effect was higher under sunlight exposre. The proportions of water loss through every avenue were maintained relatively constant either under water restriction or sunlight exposure in which the respration rate increased significantly. The findings suggest that sunlight exposure with unrestricted water resulted in a positive water balance without a significant change in organic matter intake and utilization. Water restriction resulted in a negative water balance, reducing organic matter intake and utilization. As the adaptive mechanisms, the goat appeared to be able to withstand in the harsh environment of Jeneponto by expanding plasma volume, increasing body temperature and respiration rate.

  15. Sunlight Effects on Immune System: Is There Something Else in addition to UV-Induced Immunosuppression?

    Directory of Open Access Journals (Sweden)

    D. H. González Maglio

    2016-01-01

    Full Text Available Sunlight, composed of different types of radiation, including ultraviolet wavelengths, is an essential source of light and warmth for life on earth but has strong negative effects on human health, such as promoting the malignant transformation of skin cells and suppressing the ability of the human immune system to efficiently detect and attack malignant cells. UV-induced immunosuppression has been extensively studied since it was first described by Dr. Kripke and Dr. Fisher in the late 1970s. However, skin exposure to sunlight has not only this and other unfavorable effects, for example, mutagenesis and carcinogenesis, but also a positive one: the induction of Vitamin D synthesis, which performs several roles within the immune system in addition to favoring bone homeostasis. The impact of low levels of UV exposure on the immune system has not been fully reported yet, but it bears interesting differences with the suppressive effect of high levels of UV radiation, as shown by some recent studies. The aim of this article is to put some ideas in perspective and pose some questions within the field of photoimmunology based on established and new information, which may lead to new experimental approaches and, eventually, to a better understanding of the effects of sunlight on the human immune system.

  16. Sunlight Effects on Immune System: Is There Something Else in addition to UV-Induced Immunosuppression?

    Science.gov (United States)

    Paz, M. L.; Leoni, J.

    2016-01-01

    Sunlight, composed of different types of radiation, including ultraviolet wavelengths, is an essential source of light and warmth for life on earth but has strong negative effects on human health, such as promoting the malignant transformation of skin cells and suppressing the ability of the human immune system to efficiently detect and attack malignant cells. UV-induced immunosuppression has been extensively studied since it was first described by Dr. Kripke and Dr. Fisher in the late 1970s. However, skin exposure to sunlight has not only this and other unfavorable effects, for example, mutagenesis and carcinogenesis, but also a positive one: the induction of Vitamin D synthesis, which performs several roles within the immune system in addition to favoring bone homeostasis. The impact of low levels of UV exposure on the immune system has not been fully reported yet, but it bears interesting differences with the suppressive effect of high levels of UV radiation, as shown by some recent studies. The aim of this article is to put some ideas in perspective and pose some questions within the field of photoimmunology based on established and new information, which may lead to new experimental approaches and, eventually, to a better understanding of the effects of sunlight on the human immune system. PMID:28070504

  17. Hypovitaminosis D in patients undergoing kidney transplant: the importance of sunlight exposure

    Directory of Open Access Journals (Sweden)

    Cristiane F. Vilarta

    Full Text Available OBJECTIVES: Recent studies have shown a high prevalence of hypovitaminosis D, defined as a serum 25-hydroxyvitamin D level less than 30 ng/ml, in both healthy populations and patients with chronic kidney disease. Patients undergoing kidney transplant are at an increased risk of skin cancer and are advised to avoid sunlight exposure. Therefore, these patients might share two major risk factors for hypovitaminosis D: chronic kidney disease and low sunlight exposure. This paper describes the prevalence and clinical characteristics of hypovitaminosis D among patients undergoing kidney transplant. METHODS: We evaluated 25-hydroxyvitamin D serum levels in a representative sample of patients undergoing kidney transplant. We sought to determine the prevalence of hypovitaminosis D, compare these patients with a control group, and identify factors associated with hypovitaminosis D (e.g., sunlight exposure and dietary habits. RESULTS: Hypovitaminosis D was found in 79% of patients undergoing kidney transplant, and the major associated factor was low sunlight exposure. These patients had higher creatinine and intact parathyroid hormone serum levels, with 25-hydroxyvitamin D being inversely correlated with intact parathyroid hormone serum levels. Compared with the control group, patients undergoing kidney transplant presented a higher prevalence of 25-hydroxyvitamin D deficiency and lower serum calcium, phosphate and albumin but higher creatinine and intact parathyroid hormone levels. CONCLUSIONS: Our results confirmed the high prevalence of hypovitaminosis D in patients undergoing kidney transplant. Therapeutic strategies such as moderate sunlight exposure and vitamin D supplementation should be seriously considered for this population.

  18. HISTORY OF SUNLIGHT EXPOSURE IS A RISK FACTOR FOR AGE-RELATED MACULAR DEGENERATION

    NARCIS (Netherlands)

    Schick, T.; Ersoy, L.; Lechanteur, Y.T.; Saksens, N.T.; Hoyng, C.B.; Hollander, A.I. den; Kirchhof, B.; Fauser, S.

    2016-01-01

    PURPOSE: To evaluate effects of current and past sunlight exposure and iris color on early and late age-related macular degeneration (AMD). METHODS: Of 3,701 individuals from the EUGENDA database, 752 (20.3%) showed early AMD, 1,179 (31.9%) late AMD, and 1,770 (47.8%) were controls. Information

  19. Sunlight exposure or vitamin D supplementation for vitamin D-deficient non-western immigrants: a randomized clinical trial

    NARCIS (Netherlands)

    Wicherts, I.S.; Boeke, A.J.P.; van der Meer, I.M.; van Schoor, N.M.; Knol, D.L.; Lips, P.T.A.M.

    2011-01-01

    Summary: Vitamin D deficiency is very common in non-western immigrants. In this randomized clinical trial, vitamin D 800 IU/day or 100,000 IU/3 months were compared with advised sunlight exposure. Vitamin D supplementation was more effective than advised sunlight exposure in improving vitamin D

  20. IS THERE A LINK BETWEEN SUNLIGHT EXPOSURE AND 25-HYDROXYVITAMIN D DEFICIENCY IN CHRONIC KIDNEY DISEASE PATIENTS?

    Directory of Open Access Journals (Sweden)

    Angela Yee-Moon Wang

    2012-06-01

    In conclusion, our study confirmed an extremely high prevalence of vitamin D deficiency and an important association between outdoor sunlight exposure and 25(OHD deficiency in Chinese stage 3-5 CKD patients. Further study is needed to determine whether increasing daily outdoor sunlight exposure may represent a cost-free treatment for correcting nutritional 25(OHD deficiency in the CKD population.

  1. Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited

    DEFF Research Database (Denmark)

    Glerup, H; Mikkelsen, K; Poulsen, L

    2000-01-01

    OBJECTIVES: Sunlight exposure of the skin is known to be the most important source of vitamin D. The aims of this study were: (i) to estimate vitamin D status amongst sunlight-deprived individuals (veiled Arab women, veiled ethnic Danish Moslem women and Danish controls); and (ii) through food...... intake analysis to estimate the oral intake of vitamin D necessary to keep a normal vitamin D status in sunlight-deprived individuals. DESIGN: Cross-sectional study amongst randomly selected Moslem women of Arab origin living in Denmark. Age-matched Danish women were included as controls. To control...... for racial differences, a group of veiled ethnic Danish Moslem women (all Caucasians) was included. SETTING: Primary Health Care Centre, City Vest and Department of Endocrinology and Metabolism C, University Hospital of Aarhus, Aarhus Amtssygehus, Aarhus, Denmark. SUBJECTS: Sixty-nine Arab women (60 veiled...

  2. Sunlight exposure during leisure activities and risk of prostate cancer in Montréal, Canada, 2005-2009.

    Science.gov (United States)

    Yu, Jennifer; Lavoué, Jérôme; Parent, Marie-Élise

    2014-07-28

    Prostate cancer (PCa) is the leading cause of cancer in men in many developed countries, but no modifiable risk factors have been identified. A handful of analytical studies have suggested a possible etiological role for sunlight exposure. We report here on the association between leisure-time sunlight exposure during adulthood and PCa risk in the context of a population-based case-control study. In all, 1,904 PCa cases were ascertained across Montreal French hospitals between 2005 and 2009. Concurrently, 1,962 population controls, frequency matched to cases by age (±5 years), were selected from the electoral list for French-speakers in Greater Montreal. Interviews elicited the frequency of engagement in any leisure activity during adulthood. This was used to derive cumulative sunlight exposure indices: a cumulative number of leisure activities events entailing sunlight exposure and a cumulative duration of sunlight exposure during leisure activities. Unconditional logistic regression was conducted to yield odds ratios (OR) and 95% confidence intervals (CI) for estimating the association between sunlight exposure indices and PCa risk, adjusting for age, ancestry, family history of PCa, PCa screening, education, solar protection, body mass index and physical activity. Compared with men in the upper quartile category for the number of sunlight exposure events, men never exposed during leisure time had an OR of 1.32 (95% CI: 0.82-2.14). ORs were 1.11, 0.91 and 1.00 for the first to the third quartiles of exposure, respectively. Similar results were observed for cumulative duration of exposure to sunlight, and by PCa aggressiveness. These findings provide little evidence of an association between sunlight exposure during leisure-time and PCa risk. Men with no sunlight exposure appeared at somewhat higher risks but none of the estimates achieved statistical significance.

  3. Prevention of hip fractures by exposure to sunlight and pharmacotherapy in patients with Alzheimer's disease.

    Science.gov (United States)

    Iwamoto, Jun; Sato, Yoshihiro; Tanaka, Kiyoshi; Takeda, Tsuyoshi; Matsumoto, Hideo

    2009-01-01

    Hypovitaminosis D and K due to malnutrition or sunlight deprivation, compensatory hyperparathyroidism, increased bone resorption, low bone mineral density (BMD), and an increased risk of falls may contribute to an increased risk of hip fractures in patients with Alzheimer's disease. The purpose of the present study was to clarify the efficacy of interventions against hip fractures in patients with Alzheimer's disease. With respect to randomized controlled trials (RCTs) regarding Alzheimer's disease and hip fractures, the literature was searched with PubMed. Three RCTs were identified, and the relative risk (RR) and 95% confidence interval (CI) were calculated for individual RCTs. Exposure to sunlight with calcium supplementation, menatetrenone (vitamin K2) plus calcium and vitamin D supplementation, and risedronate plus calcium and vitamin D supplementation improved hypovitaminosis D and hyperparathyroidism, contributing to a reduction in bone resorption. Risedronate itself strongly decreased bone resorption. Menatetrenone also decreased the serum level of undercarboxylated osteocalcin. The three interventions increased metacarpal BMD and reduced the incidence of hip fractures. The respective RRs (95% CI) were 0.22 (0.049-0.999), 0.13 (0.031-0.554), and 0.26 (0.100- 0.690). The present study clarified the efficacy of three interventions, including exposure to sunlight, menatetrenone, and risedronate with calcium and/or vitamin D supplementation against hip fractures in patients with Alzheimer's disease.

  4. Factors influencing adherence with therapeutic sunlight exposure in older people in intermediate care facilities.

    Science.gov (United States)

    Durvasula, Seeta; Sambrook, Philip N; Cameron, Ian D

    2012-01-01

    The purpose of this study was to investigate the factors influencing low adherence with therapeutic sunlight exposure in a randomized controlled trial conducted with older people living in intermediate care facilities. The study involved participants in the FREEDOM (Falls Risk Epidemiology: Effect of vitamin D on skeletal Outcomes and other Measures) study, a randomized controlled trial of therapeutic sun exposure to reduce falls in older people in intermediate care facilities. Semi-structured interviews were conducted with thirty participants in the FREEDOM trial, and with ten sunlight officers who were employed to facilitate the sun exposure. Two focus groups involving 10 participants in the FREEDOM trial were also held at the end of the intervention period. Common themes were derived from the interview and focus group transcripts. The study showed that the perceived health benefits did not influence adherence with the sun exposure. Factors such as socializing with others and being outdoors were more important in encouraging attendance. The main barriers to adherence included the perceived inflexibility and regimentation of daily attendance, clash with other activities, unsuitable timing and heat discomfort. This study showed that providing greater flexibility and autonomy to older people in how and when they receive sun exposure is likely to improve adherence. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Ultraviolet- and sunlight-induced lipid peroxidation in liposomal membrane

    International Nuclear Information System (INIS)

    Mandal, T.K.; Chatterjee, S.N.

    1980-01-01

    Ultraviolet radiation and sunlight caused lipid peroxidation in the liposomal membrane (as detected by measurement of the oxidation index, A 233 /A 215 , and the amount of malondialdehyde formed) and made the membrane leaky (as revealed by the release of the trapped chromate anions). The oxidation index and the formation of malondialdehyde increased linearly with increasing dose of radiation and depended significantly on the dose rate. The effects were smaller in liposomes derived from Vibrio cholerae phospholipid than in those derived from egg lecithin. The effects of the radiation dose and dose rate on hemolysis and peroxidation (MDA formation) of the erythrocyte membrane followed a similar pattern. A direct correlation between the percentage leakage of chromate (Y) and the oxidation index (X) of the liposomal system was obtained as Y = 236.5 x X

  6. Sunlight exposure and sun sensitivity associated with disability progression in multiple sclerosis.

    Science.gov (United States)

    D'hooghe, M B; Haentjens, P; Nagels, G; Garmyn, M; De Keyser, J

    2012-04-01

    Sunlight and vitamin D have been inversely associated with the risk of multiple sclerosis (MS). We investigated sunlight exposure and sun sensitivity in relation to disability progression in MS. We conducted a survey among persons with MS, registered by the Flemish MS society, Belgium, and stratified data according to relapsing-onset and progressive-onset MS. We used Kaplan-Meier survival and Cox proportional hazard regression analyses with time to Expanded Disability Status Scale (EDSS) 6 as outcome measure. Hazard ratios for the time from onset and from birth were calculated for the potentially predictive variables, adjusting for age at onset, gender and immunomodulatory treatment. 704 (51.3%) of the 1372 respondents had reached EDSS 6. In relapsing-onset MS, respondents reporting equal or higher levels of sun exposure than persons of the same age in the last 10 years had a decreased risk of reaching EDSS 6. In progressive-onset MS, increased sun sensitivity was associated with an increased hazard of reaching EDSS 6. The association of higher sun exposure with a better outcome in relapsing-onset MS may be explained by either a protective effect or reverse causality. Mechanisms underlying sun sensitivity might influence progression in progressive-onset MS.

  7. Sunlight exposure is important for preventing hip fractures in patients with Alzheimer's disease, Parkinson's disease, or stroke.

    Science.gov (United States)

    Iwamoto, J; Takeda, T; Matsumoto, H

    2012-04-01

    Hypovitaminosis D as a result of malnutrition or sunlight deprivation, increased bone resorption, low bone mineral density (BMD), or an increased risk of falls may contribute to an increased risk of hip fractures in patients with neurological diseases, including Alzheimer's disease, Parkinson's disease, and stroke. The purpose of this study was to clarify the efficacy of sunlight exposure for reducing the risk of hip fractures in patients with such neurological diseases. The English literature was searched using PubMed, and randomized controlled trials evaluating the efficacy of sunlight exposure for reducing the risk of hip fractures in patients with Alzheimer's disease, Parkinson's disease, and stroke were identified. The relative risk and the 95% confidence interval were calculated for individual randomized controlled trials, and a pooled data analysis (meta-analysis) was performed. Three randomized controlled trials were identified. Sunlight exposure improved hypovitaminosis D and increased the BMD. The relative risk (95% confidence interval) of hip fractures was 0.22 (0.05, 1.01) for Alzheimer's disease, 0.27 (0.08, 0.96) for Parkinson's disease, and 0.17 (0.02, 1.36) for stroke. The relative risk (95% confidence interval) calculated for the pooled data analysis was 0.23 (0.10, 0.56) (P = 0.0012), suggesting a significant risk reduction rate of 77%. The present meta-analysis added additional evidence indicating the efficacy of sunlight exposure for reducing the risk of hip fractures in patients with Alzheimer's disease, Parkinson's disease, and stroke. © 2011 John Wiley & Sons A/S.

  8. Sunlight-Induced Photochemical Degradation of Methylene Blue by Water-Soluble Carbon Nanorods

    Directory of Open Access Journals (Sweden)

    Anshu Bhati

    2016-01-01

    Full Text Available Water-soluble graphitic hollow carbon nanorods (wsCNRs are exploited for their light-driven photochemical activities under outdoor sunlight. wsCNRs were synthesized by a simple pyrolysis method from castor seed oil, without using any metal catalyst or template. wsCNRs exhibited the light-induced photochemical degradation of methylene blue used as a model pollutant by the generation of singlet oxygen species. Herein, we described a possible degradation mechanism of methylene blue under the irradiation of visible photons via the singlet oxygen-superoxide anion pathway.

  9. Efficacy of a dose range of simulated sunlight exposures in raising vitamin D status in South Asian adults: implications for targeted guidance on sun exposure.

    Science.gov (United States)

    Farrar, Mark D; Webb, Ann R; Kift, Richard; Durkin, Marie T; Allan, Donald; Herbert, Annie; Berry, Jacqueline L; Rhodes, Lesley E

    2013-06-01

    Vitamin D is essential for bone health, and cutaneous synthesis is an important source. South Asians cannot attain adequate amounts of vitamin D by following general recommendations on summer sunlight exposure at northerly latitudes, and increased exposure may be appropriate for improving their vitamin D status. We examined the efficacy of a dose range of simulated summer sunlight exposures in raising vitamin D status in UK adults of South Asian ethnicity. In a dose-response study, healthy adults of South Asian ethnicity (n = 60; 20-60 y old) received 1 of 6 ultraviolet exposures ranging from 0.65 to 3.9 standard erythema doses (SEDs), which were equivalent to 15-90 min unshaded noontime summer sunlight at 53.5°N (Manchester, United Kingdom), 3 times/wk for 6 wk, while wearing casual clothes that revealed a 35% skin area. Serum 25-hydroxyvitamin D [25(OH)D] was measured weekly, and dietary vitamin D was estimated. At baseline, all completing participants (n = 51) were vitamin D insufficient [25(OH)D concentrations 10 ng/mL. Targeted guidance on sunlight exposure could usefully enhance vitamin D status to avoid deficiency [25(OH)D concentration >10 ng/mL] in South Asians living at latitudes distant from the equator. This trial was registered at the ISRCTN Register (www.isrctn.org) as 07565297.

  10. Evaluation of sunlight induced structural changes and their effect on the photocatalytic activity of V{sub 2}O{sub 5} for the degradation of phenols

    Energy Technology Data Exchange (ETDEWEB)

    Aslam, M. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Ismail, Iqbal M.I. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Salah, Numan [Centre of Nanotechnology, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Chandrasekaran, S. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Qamar, M.Tariq [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Hameed, A., E-mail: afmuhammad@kau.edu.sa [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); National Centre for Physics, Quaid-e-Azam University, Islamabad 44000 (Pakistan)

    2015-04-09

    Highlights: • The interaction of UV photons of sunlight induces defects in V{sub 2}O{sub 5}. • The photon induced defects promotes the trapping and transfer of excited electrons. • The nature of the substituent at 2-position affects the degradation process. • The formation of the intermediates is influenced by the nature of substituents. • The released ions are subjected further transformation. - Abstract: Despite knowing the fact that vanadium pentoxide is slightly soluble in aqueous medium, its photocatalytic activity was evaluated for the degradation of phenol and its derivatives (2-hydroxyphenol, 2-chlorophenol, 2-aminophenol and 2-nitrophenol) in natural sunlight exposure. The prime objective of the study was to differentiate between the homogeneous and heterogeneous photocatalysis incurred by dissolved and undissolved V{sub 2}O{sub 5} in natural sunlight exposure. V{sub 2}O{sub 5} was synthesized by chemical precipitation procedure using Triton X-100 as morphology mediator and characterized by DRS, PLS, Raman, FESEM and XRD. A lower solubility of ∼5% per 100 ml of water at 23 °C was observed after calcination at 600 °C. The study revealed no contribution of the dissolved V{sub 2}O{sub 5} in the photocatalytic process. In sunlight exposure, V{sub 2}O{sub 5} powder exhibited substantial activity for the degradation, however, a low mineralization of phenolic substrates was observed. The initial low activity of V{sub 2}O{sub 5} followed by a sharp increase both in degradation and mineralization in complete spectrum sunlight exposure, was further investigated that revealed the decrease in the bandgap and the reduction in the particle size with the interaction of UV photons (<420 nm) as this effect was not observable in the exposure of visible region of sunlight. The role of the chemically different substituents attached to an aromatic ring at 2-positions and the secondary interaction of released ions during the degradation process with the reactive

  11. Formation of rutile fasciculate zone induced by sunlight irradiation at room temperature and its hemocompatibility

    International Nuclear Information System (INIS)

    Zhang, Xuan-Hui; Zheng, Xiang; Cheng, Yuan; Li, Guo-Hua; Chen, Xiao-Ping; Zheng, Jian-Hui

    2013-01-01

    The fasciculate zone of phase pure rutile was fabricated under sunlight irradiation at room temperature, using titanium tetrachloride as a sole precursor. The crystal phase, morphology and microstructure, and optical absorption behavior of the samples were characterized by X-ray Diffraction, High-Resolution Transmission Electron Microscope (HRTEM) and UV–vis Diffuse Reflectance Spectra (DRS), respectively. XRD results show that the crystal phase of the sample is composed of rutile only, and a lattice distortion displays in the crystallite of the sample. HRTEM results show that the morphology of rutile particle is fasciculate zone constituted of nanoparticles with a diameter of 4–7 nm, and these particles grow one by one and step by step. The pattern of the selected area electron diffraction of the sample is Kikuchi type, which can be attributed to the predominant orientation growth of rutile nanoparticles along [001] induced by sunlight irradiation. DRS results show that the absorption threshold of the sample is 415 nm, corresponding to the band gap energy of 2.99 eV, which is lower than the band gap energy of rutile, 3.03 eV. Blood compatibility measurement shows that the sample has no remarkable effect on hemolytic and coagulation activity. The percent hemolysis of red blood cells is less than 5% even treated with a big dosage of the fasciculate rutile and under UV irradiation, and there are no obvious changes of plasma recalcification time after the rutile treatment. Thus, the novel structure of rutile fasciculate has low potential toxicity for blood and is hemocompatibility safe. Highlights: • A novel approach to fabricate the fasciculate zone of phase pure rutile • The fasciculate grows from a particle to nanorod and to fasciculate, step by step. • A preferred orientation growth induced by sunlight irradiation in the fasciculate • The rutile fasciculate is low toxicity for blood and is hemocompatibility safe

  12. Effect of exposure to sunlight and phosphorus-limitation on bacterial degradation of coloured dissolved organic matter (CDOM) in freshwater.

    Science.gov (United States)

    Kragh, Theis; Søndergaard, Morten; Tranvik, Lars

    2008-05-01

    This study reports on the interacting effect of photochemical conditioning of dissolved organic matter and inorganic phosphorus on the metabolic activity of bacteria in freshwater. Batch cultures with lake-water bacteria and dissolved organic carbon (DOC) extracted from a humic boreal river were arranged in an experimental matrix of three levels of exposure to simulated sunlight and three levels of phosphorus concentration. We measured an increase in bacterial biomass, a decrease in DOC and bacterial respiration as CO(2) production and O(2) consumption over 450 h. These measurements were used to calculate bacterial growth efficiency (BGE). Bacterial degradation of DOC increased with increasing exposure to simulated sunlight and availability of phosphorus and no detectable growth occurred on DOC that was not pre-exposed to simulated sunlight. The outcome of photochemical degradation of DOC changed with increasing availability of phosphorus, resulting in an increase in BGE from about 5% to 30%. Thus, the availability of phosphorus has major implications for the quantitative transfer of carbon in microbial food webs.

  13. Molecular and sensory mechanisms to mitigate sunlight-induced DNA damage in treefrog tadpoles.

    Science.gov (United States)

    Schuch, André P; Lipinski, Victor M; Santos, Mauricio B; Santos, Caroline P; Jardim, Sinara S; Cechin, Sonia Z; Loreto, Elgion L S

    2015-10-01

    The increased incidence of solar ultraviolet B (UVB) radiation has been proposed as an environmental stressor, which may help to explain the enigmatic decline of amphibian populations worldwide. Despite growing knowledge regarding the UV-induced biological effects in several amphibian models, little is known about the efficacy of DNA repair pathways. In addition, little attention has been given to the interplay between these molecular mechanisms with other physiological strategies that avoid the damage induced by sunlight. Here, DNA lesions induced by environmental doses of solar UVB and UVA radiation were detected in genomic DNA samples of treefrog tadpoles (Hypsiboas pulchellus) and their DNA repair activity was evaluated. These data were complemented by monitoring the induction of apoptosis in blood cells and tadpole survival. Furthermore, the tadpoles' ability to perceive and escape from UV wavelengths was evaluated as an additional strategy of photoprotection. The results show that tadpoles are very sensitive to UVB light, which could be explained by the slow DNA repair rates for both cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6,4) pyrimidone photoproducts (6,4PPs). However, they were resistant to UVA, probably as a result of the activation of photolyases during UVA irradiation. Surprisingly, a sensory mechanism that triggers their escape from UVB and UVA light avoids the generation of DNA damage and helps to maintain the genomic integrity. This work demonstrates the genotoxic impact of both UVB and UVA radiation on tadpoles and emphasizes the importance of the interplay between molecular and sensory mechanisms to minimize the damage caused by sunlight. © 2015. Published by The Company of Biologists Ltd.

  14. A sunlight-induced method for rapid biosynthesis of silver nanoparticles using an Andrachnea chordifolia ethanol extract

    Energy Technology Data Exchange (ETDEWEB)

    Karimi Zarchi, A.A.; Faridi Majidi, R. [Tehran University of Medical Sciences, Department of Nanomedicine, School of Advanced Medical Technologies, Tehran (Iran, Islamic Republic of); Mokhtari, N.; Shahverdi, A.R. [Tehran University of Medical Sciences, Department of Pharmaceutical Biotechnology and Medicinal Plants Research Center, Faculty of Pharmacy, Tehran (Iran, Islamic Republic of); Arfan, M.; Rehman, T.; Ali, M. [University of Peshawar, Institute of Chemical Sciences, Peshawar, Khyber Pakhtoonkhwa (Pakistan); Amini, M. [Tehran University of Medical Sciences, Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran (Iran, Islamic Republic of)

    2011-05-15

    In this study a sunlight-induced method for rapid synthesis of silver nanoparticles using an ethanol extract of Andrachnea chordifolia is described. The silver nitrate solutions (1 mM) containing the ethanol extract of Andrachnea chordifolia were irradiated by both sunlight radiation and by sunlight radiation passed through different colored filters (red, yellow or green). The smallest size of silver nanoparticles was obtained when a silver ion solution was irradiated for 5 minutes by direct sunlight radiation. Further examination of the shape and size and of the surface chemistry of these biogenic silver nanoparticles, which were prepared under sunlight radiation, was carried out using transmission electron microscopy and infrared spectroscopy, respectively. Transmission electron microscopy images show spherical particles with an average size of 3.4 nm. Hydroxyl residues were also detected on the surface of these biogenic silver nanoparticles fabricated using plant extract of Andrachnea chordifolia under sunlight radiation. Our study on the reduction of silver ions by this plant extract in darkness shows that the synthesis process can take place under dark conditions at much longer incubations (48 hours). Larger silver polydispersed nanoparticles ranging in size from 3 to 30 nm were obtained when the silver ions were treated with the ethanol extract of Andrachnea chordifolia under dark conditions for 48 hours. (orig.)

  15. Patterns and timing of sunlight exposure and risk of basal cell and squamous cell carcinomas of the skin – a case–control study

    Directory of Open Access Journals (Sweden)

    Iannacone Michelle R

    2012-09-01

    Full Text Available Abstract Background Non-melanoma skin cancer (NMSC, comprised of basal (BCC and squamous (SCC cell carcinomas, is the most common cancer in Caucasians. Ultraviolet radiation (UVR exposure is the most important environmental risk factor for NMSC. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type. Methods A case–control study was conducted among Florida residents to investigate measures of patterns (intermittent vs. continuous and timing (childhood vs. adulthood of sunlight exposure in BCC and SCC. Participants included 218 BCC and 169 SCC cases recruited from a university dermatology clinic and 316 controls with no history of skin or other cancers. Results A history of blistering sunburn (a measure of intermittent sunlight exposure was associated with both BCC (OR = 1.96, 95% CI = 1.27-3.03 and SCC (OR = 2.02, 95% CI = 1.22-3.33. Additionally, having a job in the sun for ≥3 months for 10 years or longer (a measure of continuous sunlight exposure was also associated with both BCC and SCC in our study population. With the exception of younger age at first blistering sunburn, measures of younger age at sunlight exposure tended to be associated with SCC, but not BCC risk. Conclusions Results from the current study suggest that sunlight exposure is associated with both BCC and SCC risk regardless of the pattern in which the exposure was received (i.e. intermittent vs. continuous. The data also suggest that sunlight exposure at a younger age may be more important for SCC but not BCC, however additional studies are needed to further characterize sunlight exposure-response relationships in different types of NMSC.

  16. Patterns and timing of sunlight exposure and risk of basal cell and squamous cell carcinomas of the skin – a case–control study

    International Nuclear Information System (INIS)

    Iannacone, Michelle R; Fenske, Neil A; Rollison, Dana E; Wang, Wei; Stockwell, Heather G; O’Rourke, Kathleen; Giuliano, Anna R; Sondak, Vernon K; Messina, Jane L; Roetzheim, Richard G; Cherpelis, Basil S

    2012-01-01

    Non-melanoma skin cancer (NMSC), comprised of basal (BCC) and squamous (SCC) cell carcinomas, is the most common cancer in Caucasians. Ultraviolet radiation (UVR) exposure is the most important environmental risk factor for NMSC. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type. A case–control study was conducted among Florida residents to investigate measures of patterns (intermittent vs. continuous) and timing (childhood vs. adulthood) of sunlight exposure in BCC and SCC. Participants included 218 BCC and 169 SCC cases recruited from a university dermatology clinic and 316 controls with no history of skin or other cancers. A history of blistering sunburn (a measure of intermittent sunlight exposure) was associated with both BCC (OR = 1.96, 95% CI = 1.27-3.03) and SCC (OR = 2.02, 95% CI = 1.22-3.33). Additionally, having a job in the sun for ≥3 months for 10 years or longer (a measure of continuous sunlight exposure) was also associated with both BCC and SCC in our study population. With the exception of younger age at first blistering sunburn, measures of younger age at sunlight exposure tended to be associated with SCC, but not BCC risk. Results from the current study suggest that sunlight exposure is associated with both BCC and SCC risk regardless of the pattern in which the exposure was received (i.e. intermittent vs. continuous). The data also suggest that sunlight exposure at a younger age may be more important for SCC but not BCC, however additional studies are needed to further characterize sunlight exposure-response relationships in different types of NMSC

  17. Effect of exposure to sunlight and phosphorus-limitation on bacterial degradation of coloured dissolved organic matter (CDOM) in freshwater

    DEFF Research Database (Denmark)

    Kragh, Theis; Søndergaard, Morten; Tranvik, Lars

    2008-01-01

    This study reports on the interacting effect of photochemical conditioning of dissolved organic matter and inorganic phosphorus on the metabolic activity of bacteria in freshwater. Batch cultures with lake-water bacteria and dissolved organic carbon (DOC) extracted from a humic boreal river were...... arranged in an experimental matrix of three levels of exposure to simulated sunlight and three levels of phosphorus concentration. We measured an increase in bacterial biomass, a decrease in DOC and bacterial respiration as CO(2) production and O(2) consumption over 450 h. These measurements were used...

  18. Towards a Better Understanding of the Molecular Mechanisms Involved in Sunlight-Induced Melanoma

    Directory of Open Access Journals (Sweden)

    Williams Mandy

    2005-01-01

    Full Text Available Although much less prevalent than its nonmelanoma skin cancer counterparts, cutaneous malignant melanoma (CMM is the most lethal human skin cancer. Epidemiological and biological studies have established a strong link between lifetime exposure to ultraviolet (UV light, particularly sunburn in childhood, and the development of melanoma. However, the specific molecular targets of this environmental carcinogen are not known. Data obtained from genetic and molecular studies over the last few years have identified the INK4a/ARF locus as the “gatekeeper” melanoma suppressor, encoding two tumour suppressor proteins in human, p16 INK4a and p14 ARF . Recent developments in molecular biotechnology and research using laboratory animals have made a significant gene breakthrough identifying the components of the p16 INK4a /Rb pathway as the principal and rate-limiting targets of UV radiation actions in melanoma formation. This review summarizes the current knowledge of the molecular mechanisms involved in melanoma development and its relationship to sunlight UV radiation.

  19. The influence of exposure to ultraviolet radiation in simulated sunlight on ascospores causing Black Sigatoka disease of banana and plantain

    Science.gov (United States)

    Parnell, Mark; Burt, P. J. A.; Wilson, Kate

    The influence of ultraviolet (UV) radiation in simulated natural sunlight on the viability of ascospores of Mycosphaerella fijiensis, the cause of Black Sigatoka disease in banana and plantain, has been investigated as part of a study to assess the windborne spread of this pathogen from mainland Central and South America into the Caribbean. Spores were killed following continuous exposure to UV radiation for periods of 6 h or over. This relatively short exposure time suggests that the distances over which viable spores can be transported will be determined not only by the speed of the wind but also the amount of cloud cover and the time off day that spore release occurs. On this basis, wind dispersal of viable spores over distances greater than a few hundred kilometres is unlikely. These conclusions are reinforced by an examination of historical reports of the arrival of the disease in previously uninfected areas of the Americas and Africa.

  20. Effect of grape bunch sunlight exposure and UV radiation on phenolics and volatile composition of Vitis vinifera L. cv. Pinot noir wine.

    Science.gov (United States)

    Song, Jianqiang; Smart, Richard; Wang, Hua; Dambergs, Bob; Sparrow, Angela; Qian, Michael C

    2015-04-15

    The effect of canopy leaf removal and ultraviolet (UV) on Pinot noir grape and wine composition was investigated in this study. Limited basal leaf removal in the fruit zone was conducted, compared to shaded bunches. The UV exposure was controlled using polycarbonate screens to block UV radiation, and acrylic screens to pass the UV. The results showed that bunch sunlight and UV exposure significantly increased the Brix and pH in the grape juice, and increased substantially wine colour density, anthocyanins, total pigment, total phenolics and tannin content. Bunch sunlight and UV exposure affected terpene alcohols, C13-norisprenoids and other volatile composition of the wine differently. Sunlight exposure and UV resulted in increase of nerol, geraniol and citronellol but not linalool. Sunlight exposure slightly increased the concentration of β-ionone, but the increase was not statistically significant for UV treatment. Neither sunlight nor UV treatment showed any impact on the concentration of β-damascenone. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Sunlight Induced Rapid Oil Absorption and Passive Room-Temperature Release: An Effective Solution toward Heavy Oil Spill Cleanup

    KAUST Repository

    Wu, Mengchun

    2018-05-18

    Rapid cleanup and easy recovery of spilled heavy oils is always a great challenge due to their high viscosity (>103 mPa s). One of the efficient methods to absorb highly viscous oils is to reduce their viscosity by increasing their temperature. In this work, the authors integrate the sunlight‐induced light‐to‐heat conversion effect of polypyrrole (PPy) and thermoresponsive property of poly(N‐isopropylacrylamide) (PNIPAm) into the melamine sponge, which successfully delivers a fast heavy oil absorption under sunlight and passive oil release underwater at room temperature. Thanks to the rationally designed functionalities, the PNIPAm/PPy functionalized sponges possess oleophilicity and hydrophobicity under sunlight. Due to the photothermal effect of PPy, the sponges locally heat up contacting heavy oil under sunlight and reduce its viscosity to a point where the oil voluntarily flow into the pores of the sponge. The material in this work is able to rapidly absorb the heavy oil with room temperature viscosity as high as ≈1.60 × 105 mPa s. The absorbed oil can be passively forced out the sponge underwater at room temperature due to the hydrophilicity of PNIPAm. The sunlight responsive and multifunctional sponge represents a meaningful attempt in coming up with a sustainable solution toward heavy oil spill.

  2. Sunlight Induced Rapid Oil Absorption and Passive Room-Temperature Release: An Effective Solution toward Heavy Oil Spill Cleanup

    KAUST Repository

    Wu, Mengchun; Shi, Yusuf; Chang, Jian; Li, Renyuan; Ong, Chi Siang; Wang, Peng

    2018-01-01

    Rapid cleanup and easy recovery of spilled heavy oils is always a great challenge due to their high viscosity (>103 mPa s). One of the efficient methods to absorb highly viscous oils is to reduce their viscosity by increasing their temperature. In this work, the authors integrate the sunlight‐induced light‐to‐heat conversion effect of polypyrrole (PPy) and thermoresponsive property of poly(N‐isopropylacrylamide) (PNIPAm) into the melamine sponge, which successfully delivers a fast heavy oil absorption under sunlight and passive oil release underwater at room temperature. Thanks to the rationally designed functionalities, the PNIPAm/PPy functionalized sponges possess oleophilicity and hydrophobicity under sunlight. Due to the photothermal effect of PPy, the sponges locally heat up contacting heavy oil under sunlight and reduce its viscosity to a point where the oil voluntarily flow into the pores of the sponge. The material in this work is able to rapidly absorb the heavy oil with room temperature viscosity as high as ≈1.60 × 105 mPa s. The absorbed oil can be passively forced out the sponge underwater at room temperature due to the hydrophilicity of PNIPAm. The sunlight responsive and multifunctional sponge represents a meaningful attempt in coming up with a sustainable solution toward heavy oil spill.

  3. Estimation of exposure to sunlight of the liner under a tiled roof

    DEFF Research Database (Denmark)

    Holck, Ole; Rosenfeld, J.L.J.

    2005-01-01

    One construction for a pitched roof is to use tiles on battens, with a liner attached below the battens. The shape of some types of tiles is such that, at each corner where four tiles overlap, a small gap is formed. At certain positions of the sun solar radiation can penetrate through these gaps....... Simulations were carried out for a roof tilted at 25degrees, 35degrees or 45degrees, facing SE, S, SW or W. For the particular roof construction and gap studied, the maximum annual exposure of a 25 mm(2) piece of the liner placed 150 mm below the gap (corresponding to about 100 mm below the base of the tiles...... to the roof. Analytic expressions for the size of the illuminated area are obtained using a thick slit model. The accuracy of the model was assessed by some experimental measurements. The exposure over one year of the roof liner was calculated using the Design Reference Year for Copenhagen, Denmark...

  4. Screening of Metarhizium and Beauveria spp. conidia with exposure to simulated sunlight and a range of temperatures

    International Nuclear Information System (INIS)

    Morley-Davies, J.; Moore, D.; Prior, C.

    1996-01-01

    Conidia of 14 isolates of the entomopathogenic fungi Beauveria bassiana, Metarhizium flavoviride and M. anisopliae were formulated by suspending in paraffinic oil or as dry powder. Non-indicating silica gel was added to both formulations which were stored at 13 °C for at least 2 wk before exposure to a range of temperatures: −10°, 10°, 20°, 30°, 40° and 50° to determine the effects of temperature of storage on viability. At 50° the isolate studied in most detail (M. flavoviride, IMI 330189) initially showed a gradual decline in viability with 73% germination for oil samples after 60 d from an initial level of 93%, whereas the dry samples typically showed higher germination rates (initially 96% germination, dropping to 80% after 60 d). Subsequently there was a rapid decline and both oil formulated and dry conidia had lost almost all viability by 90 d. Samples of IMI 330189 stored dry or in oil, at 40° and below showed > 79% germination after 90 d. M. flavoviride 191–660 exhibited the highest temperature tolerance with >40% germination of the dry stored conidia after 90 d at 50°. Some isolates of both B. bassiana and Metarhizium spp. showed markedly lower tolerance of high temperatures. Samples stored dry usually showed greater percentage germination than samples in oil for all isolates, at all temperatures. The isolates were also exposed to 4, 8, 16 and 24 h uv light from a sunlight simulator at 40°. Conidial viability decreased markedly in all isolates with increasing uv exposure. Germination ranged between 10 and 50% after 24 h exposure to uv, 191–660 retaining highest viability. (author)

  5. Effect of soiling and sunlight exposure on the performance ratio of photovoltaic technologies in Santiago, Chile

    International Nuclear Information System (INIS)

    Urrejola, Elias; Antonanzas, Javier; Ayala, Paulo; Salgado, Marcelo; Ramírez-Sagner, Gonzalo; Cortés, Cristian; Pino, Alan; Escobar, Rodrigo

    2016-01-01

    Highlights: • Performance ratio of PV panels decays daily between 0.13% and 0.56% under soiling. • PV panel degradation is 1.29% for poly, 1.74% for mono and 2.77% for thin film. • An annual weather-corrected performance ratio of 75% is calculated. • A critical cleaning period of 45 days is proposed, no matter cleaning and energy prices. - Abstract: The performance, yearly degradation, and annual yield of photovoltaic systems have been studied in outdoor exposure for two years period 2014–2015 in Santiago, capital of Chile. Photovoltaic panels performance degrades daily in a rate between −0.13% and −0.56% under soiling in highly polluted Santiago, Chile. Yearly degradation of the arrays system was found to be in the order of 1.29% for the polycrystalline array, 1.74% for the monocrystalline array, and 2.77% for the thin film system array. The annual production yield reached 1419–1373 kW h/kWp for Poly, 1459–1444 kW h/kWp for Mono, and 1248–1236 kW h/kWp for TF, in 2014 and 2015, respectively. The annual in-plane irradiation measured reached 1981.3 kW h/m"2 and 1943.2 kW h/m"2, for 2014 and 2015, respectively. A weather-corrected performance ratio is presented showing a yearly performance ratio of around 75% for all technologies. Monthly cleaning and random rain fall have shown positive effects as primarily solutions. Furthermore, we studied the optimal strategies of cleaning for different energy prices and we defined a critical cleaning period of 45 days for a real case, independent on cleaning cost and energy prices. This work contains novel results for the Chilean capital city and can be applied to future installations in the area and serve as further insights for the development of solar energy in Chile.

  6. An integrated effect of protein intake at breakfast and morning exposure to sunlight on the circadian typology in Japanese infants aged 2-6 years.

    Science.gov (United States)

    Nakade, Miyo; Takeuchi, Hitomi; Taniwaki, Nozomi; Noji, Teruki; Harada, Tetsuo

    2009-09-01

    Tryptophan (Trp) intake at breakfast promotes morning-typed circadian typology and higher sleep quality in Japanese children aged 0-6 yrs (Harada et al., 2007). This effect may be accelerated by morning exposure to sunlight, which has not yet been tested. This study aimed to investigate such an effect in Japanese children. In May, 2006, an integrated questionnaire was administered to 0-6-year-old children attending one of 12 kindergartens. 906 parents answered the questionnaire for their children and themselves (response rate: 67.4%). The integrated questionnaire included the revised version for children of the Morningness-Eveningness (M-E) Questionnaire and questions on sleep, nutritional balance, mental health, and sunlight exposure. Analysis was made on data from 744 children aged 2-6 (385 girls, 359 boys) whose average M-E score was 20.6+/-3.46. Children who had breakfast at regular times tended to be more morning-typed and were less frequently angry (p=0.001) and depressed (p=0.007). Children who had nutritionally well-balanced breakfasts tended to be more morning-typed (pbreakfast might be a strong zeitgeber for circadian oscillators of children, and the morning-type driving effect of protein intake could be accelerated by morning exposure to sunlight.

  7. Effects of P25 TiO2 Nanoparticles on the Free Radical-Scavenging Ability of Antioxidants upon Their Exposure to Simulated Sunlight.

    Science.gov (United States)

    Li, Meng; Chong, Yu; Fu, Peter P; Xia, Qingsu; Croley, Timothy R; Lo, Y Martin; Yin, Jun-Jie

    2017-11-15

    Although nanosized ingredients, including TiO 2 nanoparticles (NPs), can be found in a wide range of consumer products, little is known about the effects these particles have on other active compounds in product matrices. These NPs can interact with reactive oxygen species (ROS), potentially disrupting or canceling the benefits expected from antioxidants. We used electron spin resonance spectrometry to assess changes in the antioxidant capacities of six dietary antioxidants (ascorbic acid, α-tocopherol, glutathione, cysteine, epicatechin, and epicatechin gallate) during exposure to P25 TiO 2 and/or simulated sunlight. Specifically, we determined the ability of these antioxidants to scavenge 1-diphenyl-2-picryl-hydrazyl radical, superoxide radical, and hydroxyl radical. Exposure to simulated sunlight alone did not lead to noticeable changes in radical-scavenging abilities; however, in combination with P25 TiO 2 NPs, the scavenging abilities of most antioxidants were weakened. We found glutathione to be the most resistant to treatment with sunlight and NPs among these six antioxidants.

  8. Psoriasis, Psoralen and Sunlight

    Directory of Open Access Journals (Sweden)

    R.P.C Naik

    1979-01-01

    Full Text Available Topical or oral administration of photoactive furocumarins followed by exposure to ultra violet light from artificial sources has been shown previously to clear psoriatic lesions. Sunlight has been chosen as the source of UVL m two separate paired comparison studies using topical and, oral 4,5, 8 trimethylpsoralen. Two out of 21 on topical therapy and none out of 6 patients on oral paired-comparison study showed faster clearance of the drug treated lesions compared to control sites.

  9. Sunlight and Vitamin D

    Science.gov (United States)

    Wacker, Matthias; Holick, Michael F.

    2013-01-01

    Vitamin D is the sunshine vitamin that has been produced on this earth for more than 500 million years. During exposure to sunlight 7-dehydrocholesterol in the skin absorbs UV B radiation and is converted to previtamin D3 which in turn isomerizes into vitamin D3. Previtamin D3 and vitamin D3 also absorb UV B radiation and are converted into a variety of photoproducts some of which have unique biologic properties. Sun induced vitamin D synthesis is greatly influenced by season, time of day, latitude, altitude, air pollution, skin pigmentation, sunscreen use, passing through glass and plastic, and aging. Vitamin D is metabolized sequentially in the liver and kidneys into 25-hydroxyvitamin D which is a major circulating form and 1,25-dihydroxyvitamin D which is the biologically active form respectively. 1,25-dihydroxyvitamin D plays an important role in regulating calcium and phosphate metabolism for maintenance of metabolic functions and for skeletal health. Most cells and organs in the body have a vitamin D receptor and many cells and organs are able to produce 1,25-dihydroxyvitamin D. As a result 1,25-dihydroxyvitamin D influences a large number of biologic pathways which may help explain association studies relating vitamin D deficiency and living at higher latitudes with increased risk for many chronic diseases including autoimmune diseases, some cancers, cardiovascular disease, infectious disease, schizophrenia and type 2 diabetes. A three-part strategy of increasing food fortification programs with vitamin D, sensible sun exposure recommendations and encouraging ingestion of a vitamin D supplement when needed should be implemented to prevent global vitamin D deficiency and its negative health consequences. PMID:24494042

  10. Human cell transformation in the study of sunlight-induced cancers in the skin of man

    International Nuclear Information System (INIS)

    Sutherland, B.M.; Bennett, P.V.

    1988-01-01

    Human cell transformation provides a powerful approach to understanding - at the cellular and molecular levels - induction of cancers in the skin of man. A principal approach to this problem is the direct transformation of human skin cells by exposure to ultraviolet and/or near-UV radiation. The frequency of human cells transformed to anchorage independence increases with radiation exposure; the relative transforming efficiencies of different wavelengths implies that direct absorption by nucleic acids is a primary initial event. Partial reversal of potential transforming lesions by photoreactivation suggests that pyrimidine dimers, as well as other lesions, are important in UV transformation of human cells. Human cells can also be transformed by transfection with cloned oncogenes, or with DNAs from tumors or tumor cell lines. Cells treated by the transfection procedure (but without DNA) or cells transfected with DNAs from normal mammalian cells or tissues show only background levels of transformation. Human cells can be transformed to anchorage-independent growth by DNAs ineffective in transformation of NIH 3T3 cells (including most human skin cancers), permitting the analysis of oncogenic molecular changes even in tumor DNAs difficult or impossible to analyze in rodent cell systems. 29 refs.; 4 figs.; 1 table

  11. Carcinogenic effect of sequential artificial sunlight and UV-A irradiation in hairless mice. Consequences for solarium 'therapy'

    International Nuclear Information System (INIS)

    Staberg, B.; Wulf, H.C.; Poulsen, T.; Klemp, P.; Brodthagen, H.

    1983-01-01

    The carcinogenic effect of artificial UV sunlight followed by UV-A irradiation in human solaria doses has been studied with the use of the hairless mouse as an animal model. Artificial sunlight exposure alone induced only a moderate skin tumor incidence (animals with at least one tumor) of 0.15 after one year, and UV-A irradiation alone induced no tumor formation. However, the combination of artificial sunlight exposure and subsequent UV-A irradiation significantly increased the tumor incidence to 0.72. We conclude that, in humans, tanning with UV-A for cosmetic purposes may not be an innocuous procedure

  12. Carotenoids content and sunlight susceptibility

    International Nuclear Information System (INIS)

    Oppezzo, Oscar J.; Costa, Cristina; Pizarro, Ramon A.

    2005-01-01

    Full text: An environmental pink pigmented bacterium was isolated and identified as Rhodococcus sp. Pigmentation mutants were obtained by chemical mutagenesis. Pigments present in the wild type strain (RMB90), in a pale yellow mutant (RMB91) and in two mutants exhibiting increased pigmentation (RMB92 and RMB93), were extracted with chloroform-methanol and analyzed by reverse phase HPLC. Survival of these strains after exposure to sunlight and ultraviolet radiation from artificial sources was studied under different physiological and irradiation conditions. The ability of RMB91 to survive sunlight exposure was reduced with respect to that of RMB90. Resistance was similar in both strains when bacteria grew in the presence of a carotenoid synthesis inhibitor, which had no effect on survival of RMB91. Reduced sunlight resistance in RMB91 was also observed during irradiations under N2. Using artificial radiation sources, non pigmented bacteria were less resistant to UVA, but not to UVB or UVC. Lethal effects of sunlight and UVA on RMB92 and RMB93 were increased with respect to the wild type strain. Carotenoids protect Rhodococcus sp against deleterious effects of sunlight. In non-photosynthetic bacteria studied to date, photo protection by carotenoids was dependent on [O 2 ]. This is not the case with Rhodococcus sp RMB90, suggesting the occurrence of a different mechanism for protection. UVA radiation seems to playa key role in photo-damage. (author)

  13. Sunlight exposure behaviour and vitamin D status in photosensitive patients: longitudinal comparative study with healthy individuals at U.K. latitude.

    Science.gov (United States)

    Rhodes, L E; Webb, A R; Berry, J L; Felton, S J; Marjanovic, E J; Wilkinson, J D; Vail, A; Kift, R

    2014-12-01

    Low vitamin D status is prevalent in wintertime in populations at northerly latitudes. Photosensitive patients are advised to practise sun avoidance, but their sunlight exposure levels, photoprotective measures and resulting vitamin D status are unknown. To examine seasonal vitamin D status in photosensitive patients relative to healthy individuals and to assess quantitatively behavioural and demographic contributors. This was a longitudinal prospective cohort study (53·5°N) examining year-round 25-hydroxyvitamin D [25(OH)D] levels, sun-exposure behaviour and oral vitamin D intake in photosensitive patients diagnosed at a photoinvestigation unit (n = 53), compared with concurrently assessed healthy adults (n = 109). Photosensitive patients achieved seasonal 25(OH)D variation, but insufficient (vitamin D intake was low in both groups (photosensitive: 2·94 μg per day). Supplementation and summer surface area exposure predicted summer peak and winter trough 25(OH)D levels. A 1 μg per day increment in supplementary vitamin D raised summer and winter 25(OH)D by 5% (95% CI 3-7) and 9% (95% CI 5-12), respectively (both P vitamin D status. Guidance on oral measures should target this patient group and their physicians. © 2014 British Association of Dermatologists.

  14. Cis-urocanic acid, a sunlight-induced immunosuppressive factor, activates immune suppression via the 5-HT2A receptor

    Science.gov (United States)

    Walterscheid, Jeffrey P.; Nghiem, Dat X.; Kazimi, Nasser; Nutt, Leta K.; McConkey, David J.; Norval, Mary; Ullrich, Stephen E.

    2006-01-01

    Exposure to UV radiation induces skin cancer and suppresses the immune response. To induce immune suppression, the electromagnetic energy of UV radiation must be absorbed by an epidermal photoreceptor and converted into a biologically recognizable signal. Two photoreceptors have been recognized: DNA and trans-urocanic acid (UCA). Trans-UCA is normally found in the outermost layer of skin and isomerizes to the cis isomer upon exposure to UV radiation. Although UCA was identified as a UV photoreceptor years ago, and many have documented its ability to induce immune suppression, its exact mode of action remains elusive. Particularly vexing has been the identity of the molecular pathway by which cis-UCA mediates immune suppression. Here we provide evidence that cis-UCA binds to the serotonin [5-hydroxytryptamine (5-HT)] receptor with relatively high affinity (Kd = 4.6 nM). Anti-cis-UCA antibody precipitates radiolabeled 5-HT, and the binding is inhibited by excess 5-HT and/or excess cis-UCA. Similarly, anti-5-HT antibody precipitates radiolabeled cis-UCA, and the binding is inhibited by excess 5-HT or excess cis-UCA. Calcium mobilization was activated when a mouse fibroblast line, stably transfected with the human 5-HT2A receptor, was treated with cis-UCA. Cis-UCA-induced calcium mobilization was blocked with a selective 5-HT2A receptor antagonist. UV- and cis-UCA-induced immune suppression was blocked by antiserotonin antibodies or by treating the mice with 5-HT2A receptor antagonists. Our findings identify cis-UCA as a serotonin receptor ligand and indicate that the immunosuppressive effects of cis-UCA and UV radiation are mediated by activation of the 5-HT2A receptor. PMID:17085585

  15. Synthesis of Ag-decorated porous TiO{sub 2} nanowires through a sunlight induced reduction method and its enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yun-Chang; Dai, Xin-Rong [Anhui & Huaihe river institute of hydraulic research, Hefei, Anhui 230088 (China); Hu, Xiao-Ye, E-mail: hxy821982@issp.ac.cn [Key Laboratory of Materials Physics, and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Huang, Su-Zhen [Institute of plasma physics, Chinese Academy of Sciences, Hefei 230031 (China); Jin, Zhen, E-mail: ftbjin@hotmail.com [Research Center for Biomimetic Functional Materials and Sensing Devices, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031 (China)

    2016-11-30

    Highlights: • The Ag-decorated porous TiO{sub 2} nanowires were succefully synthesized. • A sunlight induced ethanol reduction method for Ag decoration has been reported. • The Ag-decorated porous TiO{sub 2} nanowires exhibit excellent photocatalytic activity. • The photodegradation ratio of the as-prepared product is much higher than that of P25. - Abstract: In this work, Ag-decorated porous TiO{sub 2} nanowires were successfully synthesized via a facile and low-cost sunlight induced reduction method. The cooperation of sunlight irradiation and ethanol reduction results the formation and decoration of the Ag nanoparticles on the porous TiO{sub 2} nanowires. The structure of the Ag-decorated porous TiO{sub 2} nanowires were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Energy dispersive spectroscopy (EDS) measurements. It can be seen that the Ag nanoparticles are well dispersed within the porous TiO{sub 2} nanowires. The as-prepared Ag-decorated porous TiO{sub 2} nanowires exhibits excellent photocatalytic properties. The photocatalytic tests show that 10 ppm methylene blue can be photodegraded within 60 min. And the photodegradation ratio of the Ag-decorated porous TiO{sub 2} nanowires much higher than that of P25 and porous TiO{sub 2} nanowires. Moreover, the Ag-decorated porous TiO{sub 2} nanowires also reveal good photocatalytic activity towards to other organic pollutions, such as phenol and R6G. Therefore, it is believed that the Ag-decorated porous TiO{sub 2} nanowires can be used as a potential high performance photocatalyst in wastewater treatment.

  16. Role of Mediterranean diet, tropical vegetables rich in antioxidants, and sunlight exposure in blindness, cataract and glaucoma among African type 2 diabetics

    Science.gov (United States)

    Moïse, Mvitu Muaka; Benjamin, Longo-Mbenza; Doris, Tulomba Mona; Dalida, Kibokela Ndembe; Augustin, Nge Okwe

    2012-01-01

    AIM To assess whether regular Mediterranean diet and regular intake of vegetables may reduce the risk of blindness, cataract, and glaucoma in these type 2 diabetics. METHODS A cross-sectional design was carried out among known black diabetics admitted at the diabetic clinics of Kinshasa, between October 2008 and March 2009. The Mediterranean-style dietary score (MSDPS) was used to characterize a Mediterranean-style dietary pattern in the study population using the Harvard semi quantitative FFQ adapted for Africa. RESULTS Five hundred Type 2 diabetic patients were included in this study (48% of males; 40% aged ≥60 years). There was a significant association between blindness, cataract and aging; between blindness (P<0.05), cataract (P<0.05), glaucoma (P<0.05), and physical inactivity; between blindness (P<0.05), cataract (P<0.0001), glaucoma (P<0.01) and high SES, and a very significant association between blindness (P<0.0001), cataract (P<0.0001), glaucoma (P<0.0001) and exposure to sunlight. There was also a significant association between blindness, glaucoma, and male sex. Regular intake of Mediterranean diet, Brassica Rapa, beans, Abelmoschus, Musa acuminata reduced significantly the risk of blindness, cataract and glaucoma. CONCLUSION Regular intake of Mediterranean diet, Brassica Rapa, beans, Abelmoschus, and Musa acuminata may significantly reduce the risk of blindness or its major causes among type 2 diabetes mellitus in Africa. PMID:22762057

  17. Hydration and transparency of the rabbit cornea irradiated with UVB-doses of 0.25 J/cm(2) and 0.5 J/cm(2) compared with equivalent UVB radiation exposure reaching the human cornea from sunlight.

    Science.gov (United States)

    Cejka, Cestmír; Ardan, Taras; Sirc, Jakub; Michálek, Jiří; Beneš, Jiří; Brůnová, Blanka; Rosina, Jozef

    2011-07-01

    Exposure of the cornea to UV radiation from sunlight evokes intraocular inflammation, photokeratitis. Photokeratitis is caused by UVB radiation. It is accompanied by changes of corneal hydration and light absorption. The aim of this study was to examine the effect of two UVB doses on corneal optics in rabbits and to compare these UVB doses with the equivalent exposure of UVB radiation reaching the human cornea from sunlight. Rabbit corneas were irradiated with a daily UVB dose of 0.25 J/cm(2) or 0.5 J/cm(2) for 4 days. One day after finishing the irradiations the rabbits were sacrificed and corneal light absorption measured using our spectrophotometrical method. Corneal hydration was examined using an ultrasonic Pachymeter every experimental day before the irradiation procedure and the last day before sacrificing the animals. Changes in corneal optics appeared after the repeated exposure of the cornea to a UVB dose of 0.25 J/ cm(2) and massively increased after the repeated exposure of the cornea to a UVB dose of 0.5 J/cm(2). The first significant changes in corneal hydration appeared after a single exposure of the cornea to a UVB dose of 0.25 J/cm(2). Changes in corneal hydration appeared after the exposure of the rabbit cornea to a single UVB dose equivalent to 2.6 hours of solar UVB radiation reaching the human cornea, as measured by UVB sensors embedded in the eyes of mannequin heads facing the sun on a beach at noon in July. Repeated exposure of the rabbit cornea to the same UVB dose evoked profound changes in corneal optics. Although comparison of experimental and outdoor conditions are only approximate, the results in rabbits point to the danger for the human eye from UVB radiation when short stays in sunlight are repeated for several consecutive days without UV protection.

  18. Photochemical effects of sunlight.

    Science.gov (United States)

    Daniels, F

    1972-07-01

    The importance of sunlight in bringing about not only photosynthesis in plants, but also other photochemical effects, is reviewed. More effort should be devoted to photochemical storage of the sun's energy without the living plant. There is no theoretical reason to believe that such reactions are impossible. Ground rules for searching for suitable solar photochemical reactions are given, and a few attempts are described, but nothing successful has yet been found. Future possibilities are suggested. Photogalvanic cells which convert sunlight into electricity deserve further research. Eugene Rabinowitch has been an active pioneer in these fields.

  19. ADEQUATE UV EXPOSURES FOR HEALTHY LIFE: IN SITU MONITORING AND MODEL CALCULATION OF THE VITAMIN-D-SYNTHETIC CAPACITY OF SUNLIGHT

    Directory of Open Access Journals (Sweden)

    Irina Terenetskaya

    2012-06-01

    Full Text Available Vitamin D which is formed upon UV solar radiation in human skin is essential in many physiological functions. To estimate beneficial vitamin-D-synthetic capacity of sunlight a bio-equivalent UV dosimeter that is based on the same molecular photochemistry from which vitamin D is photosynthesized in human skin has been developed. The examples of an in situ monitoring of the vitamin-D-synthetic capacity of sunlight using an in vitro model of vitamin D synthesis are presented, and various operational principles of the UV biodosimeter are discussed. In addition, reliable algorithm is presented for direct calculation of previtamin D3 accumulation using the photoreaction mathematical model with solar UV spectra as input data. Critical dependence of previtamin D3 accumulation on cloudiness and aerosols is demonstrated.

  20. Haematogical changes induced by subchronic glyphosate exposure ...

    African Journals Online (AJOL)

    The aim of this study was to determine the haematological changes induced by subchronic glyphosate exposure in Wistar rats and the ameliorative effect of zinc. Sixty adult male and female Wistar rats were used for the study. Twelve of them were used for the LD50 which was evaluated to be 3750 mg kg-1 with clinical ...

  1. Supplementing dairy steers and organically managed dairy cows with synthetic vitamin D3 is unnecessary at pasture during exposure to summer sunlight

    DEFF Research Database (Denmark)

    Hymøller, Lone; Jensen, Søren Krogh; Lindqvist, Hanna

    2009-01-01

    Use of synthetic feed additives, including synthetic vitamin D3 (D3) in the feed for cows and other ruminants, is not consistent with the international principles of organic farming. If dairy farmers wish to produce in accordance with the organic principles, production animals would be left...... with only their endogenous production of D3 from summer sunlight as a source of D3. To examine the impact of supplemental synthetic D3 from the feed on the D3 status of dairy cattle in organic production in Nordic countries, 20 high-yielding dairy cows and 30 dairy steers were divided into two groups: one...... supplemented with synthetic D3 in the feed and one not supplemented with synthetic D3. Vitamin D3 status of the animals was assessed by measuring the concentration of the liver-derived 25-hydroxyvitamin D3 (25OHD3) in plasma. Results showed that 25OHD3 concentration in plasma from dairy cattle as well as from...

  2. Does airborne nickel exposure induce nickel sensitization?

    Science.gov (United States)

    Mann, Eugen; Ranft, Ulrich; Eberwein, Georg; Gladtke, Dieter; Sugiri, Dorothee; Behrendt, Heidrun; Ring, Johannes; Schäfer, Torsten; Begerow, Jutta; Wittsiepe, Jürgen; Krämer, Ursula; Wilhelm, Michael

    2010-06-01

    Nickel is one of the most prevalent causes of contact allergy in the general population. This study focuses on human exposure to airborne nickel and its potential to induce allergic sensitization. The study group consisted of 309 children at school-starter age living in the West of Germany in the vicinity of two industrial sources and in a rural town without nearby point sources of nickel. An exposure assessment of nickel in ambient air was available for children in the Ruhr district using routinely monitored ambient air quality data and dispersion modelling. Internal nickel exposure was assessed by nickel concentrations in morning urine samples of the children. The observed nickel sensitization prevalence rates varied between 12.6% and 30.7%. Statistically significant associations were showed between exposure to nickel in ambient air and urinary nickel concentration as well as between urinary nickel concentration and nickel sensitization. Furthermore, an elevated prevalence of nickel sensitization was associated with exposure to increased nickel concentrations in ambient air. The observed associations support the assumption that inhaled nickel in ambient air might be a risk factor for nickel sensitization; further studies in larger collectives are necessary.

  3. Accelerated stability testing of organic photovoltaics using concentrated sunlight

    DEFF Research Database (Denmark)

    Katz, Eugene A.; Manor, Assaf; Mescheloff, Asaf

    2012-01-01

    We suggest to use concentrated sunlight for accelerated studies of light-induced mechanisms in the degradation of organic photovoltaics (OPV) based on the polymer (P3HT)/fullerene (PCBM) bulk heterojunctions. Two particular cases of the degradation are reported.......We suggest to use concentrated sunlight for accelerated studies of light-induced mechanisms in the degradation of organic photovoltaics (OPV) based on the polymer (P3HT)/fullerene (PCBM) bulk heterojunctions. Two particular cases of the degradation are reported....

  4. Reversible degradation of inverted organic solar cells by concentrated sunlight

    DEFF Research Database (Denmark)

    Tromholt, Thomas; Manor, Assaf; Katz, Eugene A

    2011-01-01

    . The transient state is believed to be a result of the breakdown of the diode behaviour of the ZnO electron transport layer by O2 desorption, increasing the hole conductivity. These results imply that accelerated degradation of organic solar cells by concentrated sunlight is not a straightforward process......Concentrated sunlight was used to study the performance response of inverted P3HT:PCBM organic solar cells after exposure to high intensity sunlight. Correlations of efficiency as a function of solar intensity were established in the range of 0.5–15 suns at three different stages: for a pristine...

  5. Breast cancer induced by protracted radiation exposures

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1997-01-01

    The experience at Hiroshima/Nagasaki demonstrated that breast cancer can be induced by single doses of ionizing radiation following latencies of 10-40 years. Several epidemiological studies, usually involving ancillary low-LET radiation to the breast, have demonstrated that breast cancer can be induced by protracted exposures, with similar latencies, and with similar dependencies on dose. Radiobiologically these results suggest that the target cells involved were deficient in repair of low-LET damage even when the protraction was over months to years. Since three-quarters of breast tumors originate in the ducts where their proliferation is controlled by menstrual-cycle timed estrogen/progesterone secretions, these cells periodically were in cycle. Thus, the two main elements of a conceptual model for radon-induced lung cancer -- kinetics and deficient repair -- are satisfied. The model indicates that breast cancer could be the cumulative effect of protracted small exposures, the risk from any one of which ordinarily would be quite small. (author)

  6. Photocatalytic activity of V doped ZnO nanoparticles thin films for the removal of 2- chlorophenol from the aquatic environment under natural sunlight exposure.

    Science.gov (United States)

    Salah, Numan; Hameed, A; Aslam, M; Babkair, Saeed S; Bahabri, F S

    2016-07-15

    Vanadium doped ZnO powders were used as precursors to deposit thin films of V(5+) incorporated ZnO nanoparticles on glass substrates by the pulsed laser deposition technique. The observed variations in Raman signals, visible region shift in the diffuse reflectance spectra along with a small shift in the (101) reflections of the X-ray diffraction (XRD) confirmed the insertion of V(5+) ions in ZnO lattice. No other additional reflection in the XRD results other than ZnO further endorsed the occupation of lattice positions by V entities rather than independent oxide formation. The asymmetric XPS peaks of Zn2p and V2p core levels confirmed the existence of both in the vicinity. The existence of minimal proportion of V(3+) along with V(5+) states varied the alteration of the oxidation states V in the synthetic route. The SEM images at various resolutions displayed the uniform distribution identical nanoparticles without the presence of additional phases in the deposited films. The SEM cross-section measurements revealed the uniform thickness of ∼90 nm of each film, whereas the surface studies of the films were performed by AFM. The as-synthesized films were tested for photocatalytic activity in sunlight illumination for the removal of 2-chlorophenol. The unique feature of the study was the estimation of the photocatalytic activity 20 ppm of 2-chlorophenol by exposing the low exposed area. The degradation of the substrate was measured by liquid phase UV-vis spectroscopy, whereas total organic carbon measurement revealed the mineralization of the substrate. The released Cl(-) ions were also measured by ion chromatography. The estimated flatband potentials and pHzpc values of the V doped materials, by Mott-Schottky analysis and zeta potential measurements respectively, were correlated with the photocatalytic activity. The kinetics of the photocatalytic degradation/mineralization process was estimated and results were correlated with the plausible mechanism. Copyright

  7. Holick's rule and vitamin D from sunlight.

    Science.gov (United States)

    Dowdy, John C; Sayre, Robert M; Holick, Michael F

    2010-07-01

    Holick's rule says that sun exposure 1/4 of a minimal erythemal dose (MED) over 1/4 of a body is equivalent to 1000 International Units (IU) oral vitamin D3. Webb and Engelsen recently commented that the ultraviolet (UV) spectrum used to establish Holick's rule is unknown. They consequently used a spring midday Boston solar spectrum to estimate ample sunlight exposures for previtamin D3 (preD3) at various locations. Literature review found the source upon which this rule is based was a fluorescent sunlamp (FS lamp). The FS spectrum is known and its relative weighting against the action spectra for erythema and the preD3 is significantly different from the solar spectrum used to derive the standard vitamin D effective dose (SDD). The preD3 effectiveness of the solar spectrum per unit erythemal hazard is greater than the FS lamp by a factor of 1.32. Consequently, UV exposure estimates based on Boston reference sunlight, instead of the UV lamp employed in the originating experiments, over estimate UV exposure equivalent to approximately 1000 IU orally by approximately 1/3. This redefinition of SDD impacts risk/benefit assessments of optimal/feasible sun exposure for vitamin D maintenance and the application of Holick's rule to rational public health messages. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  8. Decreased Photochemical Efficiency of Photosystem II following Sunlight Exposure of Shade-Grown Leaves of Avocado: Because of, or in Spite of, Two Kinetically Distinct Xanthophyll Cycles?1[W

    Science.gov (United States)

    Jia, Husen; Förster, Britta; Chow, Wah Soon; Pogson, Barry James; Osmond, C. Barry

    2013-01-01

    This study resolved correlations between changes in xanthophyll pigments and photosynthetic properties in attached and detached shade-grown avocado (Persea americana) leaves upon sun exposure. Lutein epoxide (Lx) was deepoxidized to lutein (L), increasing the total pool by ΔL over 5 h, whereas violaxanthin (V) conversion to antheraxanthin (A) and zeaxanthin (Z) ceased after 1 h. During subsequent dark or shade recovery, de novo synthesis of L and Z continued, followed by epoxidation of A and Z but not of L. Light-saturated nonphotochemical quenching (NPQ) was strongly and linearly correlated with decreasing [Lx] and increasing [∆L] but showed a biphasic correlation with declining [V] and increasing [A+Z] separated when V deepoxidation ceased. When considering [ΔL+∆Z], the monophasic linear correlation was restored. Photochemical efficiency of photosystem II (PSII) and photosystem (PSI; deduced from the delivery of electrons to PSI in saturating single-turnover flashes) showed a strong correlation in their continuous decline in sunlight and an increase in NPQ capacity. This decrease was also reflected in the initial reduction of the slope of photosynthetic electron transport versus photon flux density. Generally longer, stronger sun exposures enhanced declines in both slope and maximum photosynthetic electron transport rates as well as photochemical efficiency of PSII and PSII/PSI more severely and prevented full recovery. Interestingly, increased NPQ capacity was accompanied by slower relaxation. This was more prominent in detached leaves with closed stomata, indicating that photorespiratory recycling of CO2 provided little photoprotection to avocado shade leaves. Sun exposure of these shade leaves initiates a continuum of photoprotection, beyond full engagement of the Lx and V cycle in the antenna, but ultimately photoinactivated PSII reaction centers. PMID:23213134

  9. Effects of UV, sunlight and X-ray radiation on quiescent human cells in culture

    International Nuclear Information System (INIS)

    Kantor, G.J.

    1986-01-01

    Nondividing human diploid fibroblasts (HDF) in culture have been used to study the effect on cell lethality of ultraviolet light, natural sunlight and X-rays. A lethal effect is defined as cellular degeneration, loss from the culture and inability to exclude vital strains. Far- and mid-UV have a readily observable lethal effect (cell loss), with DNA and DNA damage as the critical target and critical damage respectively. In part, natural sunlight kills cells by a similar mechanism but has an additional lethal effect at longer exposure times. This additional effect is expressed by the retention of the dead cells in culture, in contrast to the UV-induced promotion of cell degeneration and loss. Relatively large doses of X-rays that destroy proliferative capacity, have no detectable lethal effect on the maintenance of non-dividing cells. The biological response of nondividing HDF to radiations from different parts of the electromagnetic spectrum is dissimilar. (author)

  10. Reversible degradation of inverted organic solar cells by concentrated sunlight

    International Nuclear Information System (INIS)

    Tromholt, Thomas; Krebs, Frederik C; Manor, Assaf; Katz, Eugene A

    2011-01-01

    Concentrated sunlight was used to study the performance response of inverted P3HT:PCBM organic solar cells after exposure to high intensity sunlight. Correlations of efficiency as a function of solar intensity were established in the range of 0.5-15 suns at three different stages: for a pristine cell, after 30 min exposure at 5 suns and after 30 min of rest in the dark. High intensity exposure introduced a major performance decrease for all solar intensities, followed by a partial recovery of the lost performance over time: at 1 sun only 6% of the initial performance was conserved after the high intensity exposure, while after rest the performance had recovered to 60% of the initial value. The timescale of the recovery effect was studied by monitoring the cell performance at 1 sun after high intensity exposure. This showed that cell performance was almost completely restored after 180 min. The transient state is believed to be a result of the breakdown of the diode behaviour of the ZnO electron transport layer by O 2 desorption, increasing the hole conductivity. These results imply that accelerated degradation of organic solar cells by concentrated sunlight is not a straightforward process, and care has to be taken to allow for a sound accelerated lifetime assessment based on concentrated sunlight.

  11. Identification of microRNAs and their targets associated with fruit-bagging and subsequent sunlight re-exposure in the ‘Granny Smith’ apple exocarp using high-throughput sequencing

    Directory of Open Access Journals (Sweden)

    Dong eQu

    2016-02-01

    Full Text Available Bagged fruits of green apple cultivar ‘Granny Smith’ have been found to turn cardinal red after debagging during fruit-ripening in the Loess Plateau region of China. To understand such phenomenon at post-transcriptional level, we have investigated the roles of microRNAs (miRNAs in response to debagging. Three small RNA libraries were primarily constructed from peels of ‘Granny Smith’ apples subjected to bagging followed by sunlight re-exposure treatments (0h, 6h, 1d (debagging, and from peels of apples without any bagging treatments (0h, 6h, 1d. 201 known miRNAs belonging to 43 miRNA families and 220 novel miRNAs were identified via high-throughput sequencing. Some miRNAs were found to be differentially expressed after debagging, which indicated that miRNAs affected anthocyanin accumulation through their target genes in mature apple. To further explore the effect of debagging on miRNAs regulating the expression of anthocyanin regulatory genes, four miRNAs and their target genes regulating anthocyanin accumulation, miR156, miR828, miR858 and miR5072, were compared between green cultivar ‘Granny Smith’ and red cultivar ‘Starkrimson’. Results showed that mdm-miR828 and mdm-miR858 regulated anthocyanin contents in both apple cultivars, while mdm-miR156 only affected anthocyanin accumulation in ‘Granny Smith’, and miR5072 affected anthocyanin accumulation in ‘Starkrimson’. Additional analysis of gene ontology for the differentially expressed miRNAs after debagging treatments and their predicted target genes showed that they were involved in photo-protective response after debagging from 0h to 1d; they might play important roles in fruit development and adaptation to high light stress.

  12. A new mathematical approximation of sunlight attenuation in rocks for surface luminescence dating

    Energy Technology Data Exchange (ETDEWEB)

    Laskaris, Nikolaos, E-mail: nick.laskaris@gmail.com [University of the Aegean, Department of Mediterranean Studies, Laboratory of Archaeometry, 1 Demokratias Avenue, Rhodes 85100 (Greece); Liritzis, Ioannis, E-mail: liritzis@rhodes.aegean.gr [University of the Aegean, Department of Mediterranean Studies, Laboratory of Archaeometry, 1 Demokratias Avenue, Rhodes 85100 (Greece)

    2011-09-15

    The attenuation of sunlight through different rock surfaces and the thermoluminescence (TL) or Optical stimulated luminescence (OSL) residuals clock resetting derived from sunlight induced eviction of electrons from electron traps, is a prerequisite criterion for potential dating. The modeling of change of residual luminescence as a function of two variables, the solar radiation path length (or depth) and exposure time offers further insight into the dating concept. The double exponential function modeling based on the Lambert-Beer law, valid under certain assumptions, constructed by a quasi-manual equation fails to offer a general and statistically sound expression of the best fit for most rock types. A cumulative log-normal distribution fitting provides a most satisfactory mathematical approximation for marbles, marble schists and granites, where absorption coefficient and residual luminescence parameters are defined per each type of rock or marble quarry. The new model is applied on available data and age determination tests. - Highlights: > Study of aattenuation of sunlight through different rock surfaces. > Study of the thermoluminescence (TL) or Optical stimulated luminescence (OSL) residuals as a function of depth. > A Cumulative Log-Normal Distribution fitting provides the most satisfactory modeling for marbles, marble schists and granites. > The new model (Cummulative Log-Norm Fitting) is applied on available data and age determination tests.

  13. A new mathematical approximation of sunlight attenuation in rocks for surface luminescence dating

    International Nuclear Information System (INIS)

    Laskaris, Nikolaos; Liritzis, Ioannis

    2011-01-01

    The attenuation of sunlight through different rock surfaces and the thermoluminescence (TL) or Optical stimulated luminescence (OSL) residuals clock resetting derived from sunlight induced eviction of electrons from electron traps, is a prerequisite criterion for potential dating. The modeling of change of residual luminescence as a function of two variables, the solar radiation path length (or depth) and exposure time offers further insight into the dating concept. The double exponential function modeling based on the Lambert-Beer law, valid under certain assumptions, constructed by a quasi-manual equation fails to offer a general and statistically sound expression of the best fit for most rock types. A cumulative log-normal distribution fitting provides a most satisfactory mathematical approximation for marbles, marble schists and granites, where absorption coefficient and residual luminescence parameters are defined per each type of rock or marble quarry. The new model is applied on available data and age determination tests. - Highlights: → Study of aattenuation of sunlight through different rock surfaces. → Study of the thermoluminescence (TL) or Optical stimulated luminescence (OSL) residuals as a function of depth. → A Cumulative Log-Normal Distribution fitting provides the most satisfactory modeling for marbles, marble schists and granites. → The new model (Cummulative Log-Norm Fitting) is applied on available data and age determination tests.

  14. Genotoxic action of sunlight upon Bacillus subtilis spores

    International Nuclear Information System (INIS)

    Munakata, Nobuo

    1989-01-01

    Samples of Bacillus subtilis spores dried on membrane filter were exposed to natural sunlight from solar-noon time at Tokyo. The survival and mutation induction of wild-type (UVR) and repair-deficient (UVS) spores were determined on 66 occasions since 1979. Two of the values were considered to be useful in monitoring solar UV intensity; the inverse of the time (in minutes) of exposure to kill 63% of the UVS spores ('sporocidal index') and the induced mutation frequency at 60 minutes of exposure of the UVR spores ('mutagenic index'). Both values were varied greatly due to time of a year, weather and other conditions. Estimates of year-round changes under clear skies were obtained by connecting the maximum values attained in these years. In these curves, there are more than 7-fold differences in the genotoxicity between winter and summer months, with major increases observed in early spring and decreases through autumn. Using a series of UV cut-off filters, the wavelengths most effective for the sporocidal actions were estimated to be in the range of 308 - 325 nm, shorter wavelengths being effective when the genotoxicity was higher. Sunburn meter of Robertson-Berger type seems to respond to slightly longer wavelength components of the solar spectrum. However, a reasonable correlation was obtained between the reading of the meter and the sporocidal index. (author)

  15. Effects of concentrated sunlight on organic photovoltaics

    DEFF Research Database (Denmark)

    Tromholt, Thomas; Katz, Eugene A.; Hirsch, Baruch

    2010-01-01

    We report the effects of concentrated sunlight on key photovoltaic parameters and stability of organic photovoltaics (OPV). Sunlight collected and concentrated outdoors was focused into an optical fiber and delivered onto a 1 cm2 bulk-heterojunction cell. Sunlight concentration C was varied gradu...

  16. Literature review on induced exposure models, Task 2 HS-270

    Science.gov (United States)

    1982-02-01

    Sections 1, 2 and 3 of this report describe the development of : induced exposure models, together with d discussion of questions : of validity. These Sections focus on the most important and : relevant results from the literature, while Appendix A c...

  17. Mixed chemical-induced oxidative stress in occupational exposure ...

    African Journals Online (AJOL)

    Mixed chemical-induced oxidative stress in occupational exposure in Nigerians. JI Anetor, SA Yaqub, GO Anetor, AC Nsonwu, FAA Adeniyi, S Fukushima. Abstract. Exposure to single chemicals and associated disorders in occupational environments has received significant attention. Understanding these events holds ...

  18. Differential expression of ozone-induced gene during exposures to ...

    African Journals Online (AJOL)

    Differential expression of ozone-induced gene during exposures to salt stress in Polygonum sibiricum Laxm leaves, stem and underground stem. ... PcOZI-1 mRNA in untreated plants was detected at low levels in underground stem, leaves and at higher levels in stem. PcOZI-1 mRNA accumulation was transiently induced ...

  19. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.

    Science.gov (United States)

    Holick, Michael F

    2016-03-01

    Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  20. Cadmium exposure induces hematuria in Korean adults

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Seok [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Kim, Myounghee, E-mail: dkkim73@gmail.com [Department of Dental Hygiene, College of Health Science, Eulji University, Gyeonggi-do 461-713 (Korea, Republic of); Lee, Su Mi [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lee, Jung Pyo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Sejoong [Department of Internal Medicine, Seoul National University Bundang Hospital, Gyeonggi-do 463-707 (Korea, Republic of); Joo, Kwon Wook [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lim, Chun Soo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Yon Su; Kim, Dong Ki [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of)

    2013-07-15

    Introduction: Toxic heavy metals have adverse effects on human health. However, the risk of hematuria caused by heavy metal exposure has not been evaluated. Methods: Data from 4701 Korean adults were obtained in the Korean National Health and Nutritional Examination Survey (2008–2010). Blood levels of the toxic heavy metals cadmium, lead, and mercury were measured. Hematuria was defined as a result of ≥+1 on a urine dipstick test. The odds ratios (ORs) for hematuria were measured according to the blood heavy metal levels after adjusting for multiple variables. Results: Individuals with blood cadmium levels in the 3rd and 4th quartiles had a greater OR for hematuria than those in the 1st quartile group: 3rd quartile, 1.35 (1.019–1.777; P=0.037); 4th quartile, 1.52 (1.140–2.017; P=0.004). When blood cadmium was considered as a log-transformed continuous variable, the correlation between blood cadmium and hematuria was significant: OR, 1.97 (1.224–3.160; P{sub trend}=0.005). In contrast, no significant correlations between hematuria and blood lead or mercury were found in the multivariate analyses. Discussion: The present study shows that high cadmium exposure is associated with a risk of hematuria. -- Highlights: • A high level of blood cadmium is associated with a high risk of hematuria. • This correlation is independent of several confounding factors. • Blood levels of lead and mercury are not associated with risk of hematuria. • This is the first study on the correlation between cadmium exposure and hematuria risk.

  1. Port Sunlight, essai architectural et social

    OpenAIRE

    Machet, Laurence

    2017-01-01

    The purpose of this article is to examine the city of Port Sunlight, its history, design and originality. Created by William Lever in 1888 in order to house his newly-built soap factory, Port Sunlight is part of the numerous “factory villages” built in the wake of the industrial revolution according to philanthropic and utilitarian principles. But this article intends to show that Port Sunlight differs from other factory towns. Its careful design, elaborate architecture and public facilities ...

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-15

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

  4. Sunlight Modulates Fruit Metabolic Profile and Shapes the Spatial Pattern of Compound Accumulation within the Grape Cluster.

    Science.gov (United States)

    Reshef, Noam; Walbaum, Natasha; Agam, Nurit; Fait, Aaron

    2017-01-01

    Vineyards are characterized by their large spatial variability of solar irradiance (SI) and temperature, known to effectively modulate grape metabolism. To explore the role of sunlight in shaping fruit composition and cluster uniformity, we studied the spatial pattern of incoming irradiance, fruit temperature and metabolic profile within individual grape clusters under three levels of sunlight exposure. The experiment was conducted in a vineyard of Cabernet Sauvignon cv. located in the Negev Highlands, Israel, where excess SI and midday temperatures are known to degrade grape quality. Filtering SI lowered the surface temperature of exposed fruits and increased the uniformity of irradiance and temperature in the cluster zone. SI affected the overall levels and patterns of accumulation of sugars, organic acids, amino acids and phenylpropanoids, across the grape cluster. Increased exposure to sunlight was associated with lower accumulation levels of malate, aspartate, and maleate but with higher levels of valine, leucine, and serine, in addition to the stress-related proline and GABA. Flavan-3-ols metabolites showed a negative response to SI, whereas flavonols were highly induced. The overall levels of anthocyanins decreased with increased sunlight exposure; however, a hierarchical cluster analysis revealed that the members of this family were grouped into three distinct accumulation patterns, with malvidin anthocyanins and cyanidin-glucoside showing contrasting trends. The flavonol-glucosides, quercetin and kaempferol, exhibited a logarithmic response to SI, leading to improved cluster uniformity under high-light conditions. Comparing the within-cluster variability of metabolite accumulation highlighted the stability of sugars, flavan-3-ols, and cinnamic acid metabolites to SI, in contrast to the plasticity of flavonols. A correlation-based network analysis revealed that extended exposure to SI modified metabolic coordination, increasing the number of negative

  5. Sunlight and Vitamin D: A global perspective for health.

    Science.gov (United States)

    Wacker, Matthias; Holick, Michael F

    2013-01-01

    Vitamin D is the sunshine vitamin that has been produced on this earth for more than 500 million years. During exposure to sunlight 7-dehydrocholesterol in the skin absorbs UV B radiation and is converted to previtamin D3 which in turn isomerizes into vitamin D3. Previtamin D3 and vitamin D3 also absorb UV B radiation and are converted into a variety of photoproducts some of which have unique biologic properties. Sun induced vitamin D synthesis is greatly influenced by season, time of day, latitude, altitude, air pollution, skin pigmentation, sunscreen use, passing through glass and plastic, and aging. Vitamin D is metabolized sequentially in the liver and kidneys into 25-hydroxyvitamin D which is a major circulating form and 1,25-dihydroxyvitamin D which is the biologically active form respectively. 1,25-dihydroxyvitamin D plays an important role in regulating calcium and phosphate metabolism for maintenance of metabolic functions and for skeletal health. Most cells and organs in the body have a vitamin D receptor and many cells and organs are able to produce 1,25-dihydroxyvitamin D. As a result 1,25-dihydroxyvitamin D influences a large number of biologic pathways which may help explain association studies relating vitamin D deficiency and living at higher latitudes with increased risk for many chronic diseases including autoimmune diseases, some cancers, cardiovascular disease, infectious disease, schizophrenia and type 2 diabetes. A three-part strategy of increasing food fortification programs with vitamin D, sensible sun exposure recommendations and encouraging ingestion of a vitamin D supplement when needed should be implemented to prevent global vitamin D deficiency and its negative health consequences.

  6. Arsenic exposure induces the Warburg effect in cultured human cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T., E-mail: klimecki@pharmacy.arizona.edu

    2013-08-15

    Understanding how arsenic exacts its diverse, global disease burden is hampered by a limited understanding of the particular biological pathways that are disrupted by arsenic and underlie pathogenesis. A reductionist view would predict that a small number of basic pathways are generally perturbed by arsenic, and manifest as diverse diseases. Following an initial observation that arsenite-exposed cells in culture acidify their media more rapidly than control cells, the report here shows that low level exposure to arsenite (75 ppb) is sufficient to induce aerobic glycolysis (the Warburg effect) as a generalized phenomenon in cultured human primary cells and cell lines. Expanded studies in one such cell line, the non-malignant pulmonary epithelial line, BEAS-2B, established that the arsenite-induced Warburg effect was associated with increased accumulation of intracellular and extracellular lactate, an increased rate of extracellular acidification, and inhibition by the non-metabolized glucose analog, 2-deoxy-D-glucose. Associated with the induction of aerobic glycolysis was a pathway-wide induction of glycolysis gene expression, as well as protein accumulation of an established glycolysis master-regulator, hypoxia-inducible factor 1A. Arsenite-induced alteration of energy production in human cells represents the type of fundamental perturbation that could extend to many tissue targets and diseases. - Highlights: • Chronic arsenite exposure induces aerobic glycolysis, dubbed the “Warburg effect”. • Arsenite-induced Warburg effect is a general phenomenon in cultured human cells. • HIF-1A may mediate arsenite induced Warburg effect.

  7. Arsenic exposure induces the Warburg effect in cultured human cells

    International Nuclear Information System (INIS)

    Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T.

    2013-01-01

    Understanding how arsenic exacts its diverse, global disease burden is hampered by a limited understanding of the particular biological pathways that are disrupted by arsenic and underlie pathogenesis. A reductionist view would predict that a small number of basic pathways are generally perturbed by arsenic, and manifest as diverse diseases. Following an initial observation that arsenite-exposed cells in culture acidify their media more rapidly than control cells, the report here shows that low level exposure to arsenite (75 ppb) is sufficient to induce aerobic glycolysis (the Warburg effect) as a generalized phenomenon in cultured human primary cells and cell lines. Expanded studies in one such cell line, the non-malignant pulmonary epithelial line, BEAS-2B, established that the arsenite-induced Warburg effect was associated with increased accumulation of intracellular and extracellular lactate, an increased rate of extracellular acidification, and inhibition by the non-metabolized glucose analog, 2-deoxy-D-glucose. Associated with the induction of aerobic glycolysis was a pathway-wide induction of glycolysis gene expression, as well as protein accumulation of an established glycolysis master-regulator, hypoxia-inducible factor 1A. Arsenite-induced alteration of energy production in human cells represents the type of fundamental perturbation that could extend to many tissue targets and diseases. - Highlights: • Chronic arsenite exposure induces aerobic glycolysis, dubbed the “Warburg effect”. • Arsenite-induced Warburg effect is a general phenomenon in cultured human cells. • HIF-1A may mediate arsenite induced Warburg effect

  8. Will parental exposure to radiation induce tumor in sibling ?

    International Nuclear Information System (INIS)

    Watanabe, Hiromitsu; Takahashi, Tadateru; Toyota, Kazuhiro; Ito, Akihiro

    1991-01-01

    There are reports of possible risk of transmission of genetic trait(s) through the germ cell in acquired cancer from parent to sibling. We have confirmed that paternal exposure to 252 Cf neutron irradiation in mice induced sperm abnormality leading to dominant lethals and liver tumors at F 1 offspring. On the other hand, C3H male mice have been known to have high incidence of spontaneous hepatic tumors and increased hepatic tumor risk in F 1 offsprings maybe caused by the genetic transmission of the hepatoma-inducible-trait amplified by 252 Cf neutron irradiation. The present paper describes that paternal exposure to X-ray or chemicals induces heritable characteristics including anomalies and tumors in some special strains of mice and rats. Some possible mechanisms of transmission of genetic trait(s) are also discussed. (author) 52 refs

  9. Secondhand smoke exposure induces acutely airway acidification and oxidative stress.

    Science.gov (United States)

    Kostikas, Konstantinos; Minas, Markos; Nikolaou, Eftychia; Papaioannou, Andriana I; Liakos, Panagiotis; Gougoura, Sofia; Gourgoulianis, Konstantinos I; Dinas, Petros C; Metsios, Giorgos S; Jamurtas, Athanasios Z; Flouris, Andreas D; Koutedakis, Yiannis

    2013-02-01

    Previous studies have shown that secondhand smoke induces lung function impairment and increases proinflammatory cytokines. The aim of the present study was to evaluate the acute effects of secondhand smoke on airway acidification and airway oxidative stress in never-smokers. In a randomized controlled cross-over trial, 18 young healthy never-smokers were assessed at baseline and 0, 30, 60, 120, 180 and 240 min after one-hour secondhand smoke exposure at bar/restaurant levels. Exhaled NO and CO measurements, exhaled breath condensate collection (for pH, H(2)O(2) and NO(2)(-)/NO(3)(-) measurements) and spirometry were performed at all time-points. Secondhand smoke exposure induced increases in serum cotinine and exhaled CO that persisted until 240 min. Exhaled breath condensate pH decreased immediately after exposure (p secondhand smoke induced airway acidification and increased airway oxidative stress, accompanied by significant impairment of lung function. Despite the reversal in EBC pH and lung function, airway oxidative stress remained increased 4 h after the exposure. Clinical trial registration number (EudraCT): 2009-013545-28. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Effects of gamma rays, ultraviolet radiation, sunlight, microwaves and electromagnetic fields on gene expression mediated by human immunodeficiency virus promoter

    International Nuclear Information System (INIS)

    Libertin, C.R.; Woloschak, G.E.; Panozzo, J.; Groh, K.R.; Chang-Liu, Chin-Mei; Schreck, S.

    1994-01-01

    Previous work by our group and others has shown the modulation of human immunodeficiency virus (HIV) promoter or long terminal repeat (LTR) after exposure to neutrons and ultraviolet radiations. Using HeLa cells stably transfected with a construct containing the chloramphenicol acetyl transferase (CAT) gene, the transcription of which is mediated by the HIV-LTR, we designed experiments to examine the effects of exposure to different types of radiation (such as γ rays, ultraviolet and sunlight irradiations, electromagnetic fields and microwaves) in HIV-LTR-driven expression of CAT. These results demonstrated ultraviolet-light-induced transcription from the HIV promoter, as has been shown by others. Exposure to other DNA-damaging agents such as γ rays and sunlight (with limited exposures) had no significant effect on transcription mediated by HIV-LTR, suggesting that induction of HIV is not mediated by just any type of DNA damage but rather may require specific types of DNA damage. Microwaves did not cause cell killing when cells in culture were exposed in high volumes of medium, and the same cells showed no changes in expression. When microwave exposure was carried out in low volumes of medium (so that excessive heat was generated) induction of HIV-LTR transcription (as assayed by CAT activity) was evident. Electromagnetic field exposures had no effect on expression of HIV-LTR. These results demonstrate that not all types of radiation and not all DNA-damaging agents are capable of inducing HIV. We hypothesize that induction of HIV transcription may be mediated by several different signals exposure to radiation. 22 refs., 8 figs

  11. Microcystin-LR exposure induces developmental neurotoxicity in zebrafish embryo

    International Nuclear Information System (INIS)

    Wu, Qin; Yan, Wei; Liu, Chunsheng; Li, Li; Yu, Liqin; Zhao, Sujuan; Li, Guangyu

    2016-01-01

    Microcystin-LR (MCLR) is a commonly acting potent hepatotoxin and has been pointed out of potentially causing developmental neurotoxicity, but the exact mechanism is little known. In this study, zebrafish embryos were exposed to 0, 0.8, 1.6 or 3.2 mg/L MCLR for 120 h. MCLR exposure through submersion caused serious hatching delay and body length decrease. The content of MCLR in zebrafish larvae was analyzed and the results demonstrated that MCLR can accumulate in zebrafish larvae. The locomotor speed of zebrafish larvae was decreased. Furthermore, the dopamine and acetylcholine (ACh) content were detected to be significantly decreased in MCLR exposure groups. And the acetylcholinesterase (AChE) activity was significantly increased after exposure to 1.6 and 3.2 mg/L MCLR. The transcription pattern of manf, chrnα7 and ache gene was consistent with the change of the dopamine content, ACh content and AChE activity. Gene expression involved in the development of neurons was also measured. α1-tubulin and shha gene expression were down-regulated, whereas mbp and gap43 gene expression were observed to be significantly up-regulated upon exposure to MCLR. The above results indicated that MCLR-induced developmental toxicity might attribute to the disorder of cholinergic system, dopaminergic signaling, and the development of neurons. - Highlights: • MCLR accumulation induces developmental neurotoxicity in zebrafish embryo. • The decrease of dopamine levels might be associated with the MCLR-induced developmental neurotoxicity in zebrafish larvae. • The alternation of cholinergic system might contribute to the change of neurobehavior in zebrafish larvae exposure with MCLR. - MCLR accumulation induces developmental neurotoxicity by affecting cholinergic system, dopaminergic signaling, and the development of neurons in zebrafish embryo.

  12. Lead Exposure Induces Telomere Instability in Human Cells.

    Directory of Open Access Journals (Sweden)

    Géraldine Pottier

    Full Text Available Lead (Pb is an important environmental contaminant due to its widespread use over many centuries. While it affects primarily every organ system of the body, the most pernicious effects of Pb are on the central nervous system leading to cognitive and behavioral modification. Despite decades of research, the mechanisms responsible for Pb toxicity remain poorly understood. Recent work has suggested that Pb exposure may have consequences on chromosomal integrity as it was shown that Pb exposure leads to the generation of γH2Ax foci, a well-established biomarker for DNA double stranded break (DSB formation. As the chromosomal localization of γH2Ax foci plays an important role in determining the molecular mechanism responsible for their formation, we examined the localization of Pb-induced foci with respect to telomeres. Indeed, short or dysfunctional telomeres (uncapped or damaged telomeres may be recognized as DSB by the DNA repair machinery, leading to "telomere-Induced Foci" (TIFs. In the current study, we show that while Pb exposure did not increase intra-chromosomal foci, it significantly induced TIFs, leading in some cases, to chromosomal abnormalities including telomere loss. The evidence suggests that these chromosomal abnormalities are likely due to perturbation of telomere replication, in particular on the lagging DNA strand. We propose a mechanism by which Pb exposure leads to the loss of telomere maintenance. As numerous studies have demonstrated a role for telomere maintenance in brain development and tissue homeostasis, our results suggest a possible mechanism for lead-induced neurotoxicity.

  13. Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

    International Nuclear Information System (INIS)

    Spector, A.C.; Smith, J.C.; Hollander, G.R.

    1986-01-01

    Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial

  14. Environmental Arsenic Exposure and Microbiota in Induced Sputum

    Directory of Open Access Journals (Sweden)

    Allison G. White

    2014-02-01

    Full Text Available Arsenic exposure from drinking water is associated with adverse respiratory outcomes, but it is unknown whether arsenic affects pulmonary microbiota. This exploratory study assessed the effect of exposure to arsenic in drinking water on bacterial diversity in the respiratory tract of non-smokers. Induced sputum was collected from 10 subjects with moderate mean household water arsenic concentration (21.1 ± 6.4 ppb and 10 subjects with low household water arsenic (2.4 ± 0.8 ppb. To assess microbiota in sputum, the V6 hypervariable region amplicons of bacterial 16s rRNA genes were sequenced using the Ion Torrent Personal Genome Machine. Microbial community differences between arsenic exposure groups were evaluated using QIIME and Metastats. A total of 3,920,441 sequence reads, ranging from 37,935 to 508,787 per sample for 316 chips after QIIME quality filtering, were taxonomically classified into 142 individual genera and five phyla. Firmicutes (22%, Proteobacteria (17% and Bacteriodetes (12% were the main phyla in all samples, with Neisseriaceae (15%, Prevotellaceae (12% and Veillonellacea (7% being most common at the genus level. Some genera, including Gemella, Lactobacillales, Streptococcus, Neisseria and Pasteurellaceae were elevated in the moderate arsenic exposure group, while Rothia, Prevotella, Prevotellaceae Fusobacterium and Neisseriaceae were decreased, although none of these differences was statistically significant. Future studies with more participants and a greater range of arsenic exposure are needed to further elucidate the effects of drinking water arsenic consumption on respiratory microbiota.

  15. Modelling the exposure induced by a criticality excursion in solution

    International Nuclear Information System (INIS)

    Kerouanton, David; Delgovea, Laure; Castaniera, Eric; Raimondia, Nicolas

    2008-01-01

    During a criticality accident, significant exposure is generated by 4 radiation origins: radiation directly induced by fissions (prompt neutrons and gamma), gamma radiations induced by (n, γ) reactions in crossed materials (capture gamma) and gamma radiations emitted by fission products. Due to boiling of the solution, a fraction of fissions products is airborne and is deposited in the ventilation shafts. 5.10 18 fissions are considered in a dissolution tank containing uranyl nitrate by using the deterministic ATTILA radiation transport code. Instantaneous radiations rates are evaluated as a function of the distance and compared with data available in the literature. Dose rates induced behind various shielding materials such as concrete, steel or glass are assessed. In all cases, relative contributions of prompt or capture radiations is detailed. (author)

  16. Influence of thermoluminescence signal for debris flow surface materials by sunlight bleaching

    International Nuclear Information System (INIS)

    Song Bo; Wei Mingjian; He Youbing; Zhou Rui; Zhao Qiuyue; Zhang Bin

    2013-01-01

    Thermoluminescence was utilized for measuring the thermoluminescence signals of the standard debris flow samples which were bleached by simulated sunlight and debris flow samples after real sunlight bleaching. The experiment results demonstrate that light bleaching phenomenon of the debris flow occurs when it experiences a period of exposure. The thermoluminescence signal of the samples weakens gradually with the increase of depth. The optical bleaching phenomenon is obvious. Within a certain depth, light bleaching phenomenon is enhanced with the increase of light intensity. The annealing depth of simulated sunlight bleaching experiment is about 1 mm, and the actual annealing depth of sunlight bleaching is about 6 mm. According to the equivalent dose variation with depth, the mud of natural debris flow can be divided into two stages. It has fundamental significance in the application of thermoluminescence dating techniques to divide the stages of debris flow sediments. (authors)

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

    Science.gov (United States)

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

    2018-08-01

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

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

  19. Titanium Dioxide Exposure Induces Acute Eosinophilic Lung Inflammation in Rabbits

    Science.gov (United States)

    CHOI, Gil Soon; OAK, Chulho; CHUN, Bong-Kwon; WILSON, Donald; JANG, Tae Won; KIM, Hee-Kyoo; JUNG, Mannhong; TUTKUN, Engin; PARK, Eun-Kee

    2014-01-01

    Titanium dioxide (TiO2) is increasingly widely used in industrial, commercial and home products. TiO2 aggravates respiratory symptoms by induction of pulmonary inflammation although the mechanisms have not been well investigated. We aimed to investigate lung inflammation in rabbits after intratracheal instillation of P25 TiO2. One ml of 10, 50 and 250 µg of P25 TiO2 was instilled into one of the lungs of rabbits, chest computed-tomography was performed, and bronchoalveolar lavage (BAL) fluid was collected before, at 1 and 24 h after P25 TiO2 exposure. Changes in inflammatory cells in the BAL fluids were measured. Lung pathological assay was also carried out at 24 h after P25 TiO2 exposure. Ground glass opacities were noted in both lungs 1 h after P25 TiO2 and saline (control) instillation. Although the control lung showed complete resolution at 24 h, the lung exposed to P25 TiO2 showed persistent ground glass opacities at 24 h. The eosinophil counts in BAL fluid were significantly increased after P25 TiO2 exposure. P25 TiO2 induced a dose dependent increase of eosinophils in BAL fluid but no significant differences in neutrophil and lymphocyte cell counts were detected. The present findings suggest that P25 TiO2 induces lung inflammation in rabbits which is associated with eosinophilic inflammation. PMID:24705802

  20. Fertilization Induces a Transient Exposure of Phosphatidylserine in Mouse Eggs

    Science.gov (United States)

    Curia, Claudio A.; Ernesto, Juan I.; Stein, Paula; Busso, Dolores; Schultz, Richard M.; Cuasnicu, Patricia S.; Cohen, Débora J.

    2013-01-01

    Phosphatidylserine (PS) is normally localized to the inner leaflet of the plasma membrane and the requirement of PS translocation to the outer leaflet in cellular processes other than apoptosis has been demonstrated recently. In this work we investigated the occurrence of PS mobilization in mouse eggs, which express flippase Atp8a1 and scramblases Plscr1 and 3, as determined by RT-PCR; these enzyme are responsible for PS distribution in cell membranes. We find a dramatic increase in binding of flouresceinated-Annexin-V, which specifically binds to PS, following fertilization or parthenogenetic activation induced by SrCl2 treatment. This increase was not observed when eggs were first treated with BAPTA-AM, indicating that an increase in intracellular Ca2+ concentration was required for PS exposure. Fluorescence was observed over the entire egg surface with the exception of the regions overlying the meiotic spindle and sperm entry site. PS exposure was also observed in activated eggs obtained from CaMKIIγ null females, which are unable to exit metaphase II arrest despite displaying Ca2+ spikes. In contrast, PS exposure was not observed in TPEN-activated eggs, which exit metaphase II arrest in the absence of Ca2+ release. PS exposure was also observed when eggs were activated with ethanol but not with a Ca2+ ionophore, suggesting that the Ca2+ source and concentration are relevant for PS exposure. Last, treatment with cytochalasin D, which disrupts microfilaments, or jasplakinolide, which stabilizes microfilaments, prior to egg activation showed that PS externalization is an actin-dependent process. Thus, the Ca2+ rise during egg activation results in a transient exposure of PS in fertilized eggs that is not associated with apoptosis. PMID:23951277

  1. Sunlight technologies for photochemical deactivation of organic pollutants in water

    Energy Technology Data Exchange (ETDEWEB)

    Acher, A.; Fischer, E.; Tornheim, R. [The Volcani Center, Inst. of Soils and Water, Bet Dagan (Israel); Manor, Y. [Sheba Medical Center, Central Virology Lab., Ramat Gan (Israel)

    1997-12-31

    Sensitized-photochemical oxidation methods aimed at use in water treatment technologies for deactivation of biotic (microorganisms) and/or of xenobiotic (pesticides) pollutants in water were developed using global solar radiation or concentrated sunlight (up to 250 suns). The solar global radiation was used either for detoxification of industrial waste water from a pesticide factory to allow their discharge into the urban sewer, or for disinfection of domestric effluents to be used in crop irrigation. The disinfection process was eventually carried out in an experimental pilot-scale plant, capable of disinfection up to 50 m{sup 3}/h of effluent supplied by an activated sludge sewage treatment plant located in Tel-Aviv area. The treated effluents did not show any regrowth of the microorganisms during 7 days. The solar concentrated radiation experiments performed using facilities of the Sun Tower of The Weizman Institute of Science, Rehovot. The concentrated sunlight was provided by different combination of several computer controlled heliostates, up to 8, that track the sun and focus the received sunlight onto the target situated on the roof of the sun-tower. The sunlight intensities measured on the target reached up to 200 kW/m{sup 2}. The experiments were performed either batch- or continuous-wise. The water-samples exposed to disinfection were the above effluent, filtered and supplemented with vaccine strain poliovirus or with different concentrations of an industrial potential pollutant (bromacil), MB 2 mg/L and two concentrations of dissolved oxygen (8.0 or 40.0 mg O{sub 2}/L). An exposure time of 2-3 seconds at 150 kW/m{sup 2} was decreased the microorganisms alive (counts) by five orders of magnitude. A comparison between the two above water treatment technologies is presented. (orig./SR)

  2. Recurring ethanol exposure induces disinhibited courtship in Drosophila.

    Directory of Open Access Journals (Sweden)

    Hyun-Gwan Lee

    Full Text Available Alcohol has a strong causal relationship with sexual arousal and disinhibited sexual behavior in humans; however, the physiological support for this notion is largely lacking and thus a suitable animal model to address this issue is instrumental. We investigated the effect of ethanol on sexual behavior in Drosophila. Wild-type males typically court females but not males; however, upon daily administration of ethanol, they exhibited active intermale courtship, which represents a novel type of behavioral disinhibition. The ethanol-treated males also developed behavioral sensitization, a form of plasticity associated with addiction, since their intermale courtship activity was progressively increased with additional ethanol experience. We identified three components crucial for the ethanol-induced courtship disinhibition: the transcription factor regulating male sex behavior Fruitless, the ABC guanine/tryptophan transporter White and the neuromodulator dopamine. fruitless mutant males normally display conspicuous intermale courtship; however, their courtship activity was not enhanced under ethanol. Likewise, white males showed negligible ethanol-induced intermale courtship, which was not only reinstated but also augmented by transgenic White expression. Moreover, inhibition of dopamine neurotransmission during ethanol exposure dramatically decreased ethanol-induced intermale courtship. Chronic ethanol exposure also affected a male's sexual behavior toward females: it enhanced sexual arousal but reduced sexual performance. These findings provide novel insights into the physiological effects of ethanol on sexual behavior and behavioral plasticity.

  3. Early embryonic androgen exposure induces transgenerational epigenetic and metabolic changes.

    Science.gov (United States)

    Xu, Ning; Chua, Angela K; Jiang, Hong; Liu, Ning-Ai; Goodarzi, Mark O

    2014-08-01

    Androgen excess is a central feature of polycystic ovary syndrome (PCOS), which affects 6% to 10% of young women. Mammals exposed to elevated androgens in utero develop PCOS-like phenotypes in adulthood, suggesting fetal origins of PCOS. We hypothesize that excess androgen exposure during early embryonic development may disturb the epigenome and disrupt metabolism in exposed and unexposed subsequent generations. Zebrafish were used to study the underlying mechanism of fetal origins. Embryos were exposed to androgens (testosterone and dihydrotestosterone) early at 26 to 56 hours post fertilization or late at 21 to 28 days post fertilization. Exposed zebrafish (F0) were grown to adults and crossed to generate unexposed offspring (F1). For both generations, global DNA methylation levels were examined in ovaries using a luminometric methylation assay, and fasting and postprandial blood glucose levels were measured. We found that early but not late androgen exposure induced changes in global methylation and glucose homeostasis in both generations. In general, F0 adult zebrafish exhibited altered global methylation levels in the ovary; F1 zebrafish had global hypomethylation. Fasting blood glucose levels were decreased in F0 but increased in F1; postprandial glucose levels were elevated in both F0 and F1. This androgenized zebrafish study suggests that transient excess androgen exposure during early development can result in transgenerational alterations in the ovarian epigenome and glucose homeostasis. Current data cannot establish a causal relationship between epigenetic changes and altered glucose homeostasis. Whether transgenerational epigenetic alteration induced by prenatal androgen exposure plays a role in the development of PCOS in humans deserves study.

  4. Adaptive response induced by occupational exposures to ionizing radiation

    International Nuclear Information System (INIS)

    Barquinero, J.F.; Caballin, M.R.; Barrios, L.; Murtra, P.; Egozcue, J.; Miro, R.; Ribas, M.

    1997-01-01

    We have found a significant decreased sensitivity to the cytogenetic effects of ionizing radiation (IR) and bleomycin (BLM) in lymphocytes from individuals occupationally exposed to IR when compared with a control population. These results suggest that occupational exposures to IR can induce adaptive response that can be detected by a subsequent treatment by IR or by BLM. However, no correlation between the results obtained with both treatments was observed. A great heterogeneity in the frequencies of chromatid aberrations induced by BLM was observed. The study of the influence of different harvesting times showed that there was no correlation with the frequencies of chromatid breaks. Our results indicate that the use of BLM to detect adaptive response has several difficulties at the individual level. (author)

  5. Adaptive response induced by occupational exposures to ionizing radiation

    International Nuclear Information System (INIS)

    Barquinero, J.F.; Caballin, M.R.; Barrios, L.; Egozcue, J.; Miro, R.; Ribas, M.

    1997-01-01

    We have found a significant decreased sensitivity to the cytogenetic effects of both ionizing radiation (IR) (2 Gy of γ rays) and bleomycin (BLM, 0,03 U/ml), in lymphocytes from individuals occupationally exposed to IR when compared with controls. These results suggest that occupational exposures to IR can induce adaptive response that can be detected by a subsequent treatment either by IR or by BLM. When a comparison is made between the cytogenetic effects of both treatments, no correlation was observed at the individual level. On the other hand, the individual frequencies of chromosome aberrations induced by a challenge dose of IR were negatively correlated with the occupationally received doses during the last three years. This correlation was not observed after the challenge treatment of BLM. Moreover, the individual frequencies of chromosome aberrations induced by IR treatment were homogeneous. This is not the case of the individual frequencies of chromatid aberrations induced by BLM, where a great heterogeneity was observed. (authors)

  6. Amorphous nanosilicas induce consumptive coagulopathy after systemic exposure

    International Nuclear Information System (INIS)

    Nabeshi, Hiromi; Yoshikawa, Tomoaki; Matsuyama, Keigo; Nakazato, Yasutaro; Arimori, Akihiro; Isobe, Masaaki; Tochigi, Saeko; Kondoh, Sayuri; Hirai, Toshiro; Akase, Takanori; Yamashita, Takuya; Yamashita, Kohei; Yoshida, Tokuyuki; Itoh, Norio; Nagano, Kazuya; Abe, Yasuhiro; Yoshioka, Yasuo; Kamada, Haruhiko; Imazawa, Takayoshi; Kondoh, Masuo

    2012-01-01

    We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs. (paper)

  7. Amorphous nanosilicas induce consumptive coagulopathy after systemic exposure

    Science.gov (United States)

    Nabeshi, Hiromi; Yoshikawa, Tomoaki; Matsuyama, Keigo; Nakazato, Yasutaro; Arimori, Akihiro; Isobe, Masaaki; Tochigi, Saeko; Kondoh, Sayuri; Hirai, Toshiro; Akase, Takanori; Yamashita, Takuya; Yamashita, Kohei; Yoshida, Tokuyuki; Nagano, Kazuya; Abe, Yasuhiro; Yoshioka, Yasuo; Kamada, Haruhiko; Imazawa, Takayoshi; Itoh, Norio; Kondoh, Masuo; Yagi, Kiyohito; Mayumi, Tadanori; Tsunoda, Shin-ichi; Tsutsumi, Yasuo

    2012-02-01

    We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs.

  8. Acrolein exposure suppresses antigen-induced pulmonary inflammation

    Science.gov (United States)

    2013-01-01

    Background Adverse health effects of tobacco smoke arise partly from its influence on innate and adaptive immune responses, leading to impaired innate immunity and host defense. The impact of smoking on allergic asthma remains unclear, with various reports demonstrating that cigarette smoke enhances asthma development but can also suppress allergic airway inflammation. Based on our previous findings that immunosuppressive effects of smoking may be largely attributed to one of its main reactive electrophiles, acrolein, we explored the impact of acrolein exposure in a mouse model of ovalbumin (OVA)-induced allergic asthma. Methods C57BL/6 mice were sensitized to ovalbumin (OVA) by intraperitoneal injection with the adjuvant aluminum hydroxide on days 0 and 7, and challenged with aerosolized OVA on days 14–16. In some cases, mice were also exposed to 5 ppm acrolein vapor for 6 hrs/day on days 14–17. Lung tissues or brochoalveolar lavage fluids (BALF) were collected either 6 hrs after a single initial OVA challenge and/or acrolein exposure on day 14 or 48 hrs after the last OVA challenge, on day 18. Inflammatory cells and Th1/Th2 cytokine levels were measured in BALF, and lung tissue samples were collected for analysis of mucus and Th1/Th2 cytokine expression, determination of protein alkylation, cellular thiol status and transcription factor activity. Results Exposure to acrolein following OVA challenge of OVA-sensitized mice resulted in markedly attenuated allergic airway inflammation, demonstrated by decreased inflammatory cell infiltrates, mucus hyperplasia and Th2 cytokines. Acrolein exposure rapidly depleted lung tissue glutathione (GSH) levels, and induced activation of the Nrf2 pathway, indicated by accumulation of Nrf2, increased alkylation of Keap1, and induction of Nrf2-target genes such as HO-1. Additionally, analysis of inflammatory signaling pathways showed suppressed activation of NF-κB and marginally reduced activation of JNK in acrolein

  9. Sunlight inactivation of Escherichia coli in waste stabilization microcosms in a sahelian region (Ouagadougou, Burkina Faso).

    Science.gov (United States)

    Maïga, Ynoussa; Denyigba, Kokou; Wethe, Joseph; Ouattara, Aboubakar Sidiki

    2009-02-09

    Experiments on sunlight inactivation of Escherichia coli were conducted from November 2006 to June 2007 in eight outdoors microcosms with different depths filled with maturation pond wastewater in order to determine pond depth influence on sunlight inactivation of E. coli. The long-term aim was to maximize sunlight inactivation of waterborne pathogens in waste stabilization ponds (WSPs) in sahelian regions where number of sunny days enable longer exposure of wastewater to sunlight. The inactivation was followed during daylight from 8.00 h to 17.00 h and during the night. Sunlight inactivation rates (K(S)), as a function of cumulative global solar radiation (insolation), were 16 and 24 times higher than the corresponding dark inactivation (K(D)) rates, respectively in cold and warm season. In warm season, E. coli was inactivated far more rapidly. Inactivation of E. coli follows the evolution of radiation during the day. In shallow depth microcosms, E. coli was inactivated far more rapidly than in high depth microcosms. The physical chemical parameters [pH, dissolved oxygen (DO)] of microcosms water were higher in shallow depth microcosms than in high depth microcosms suggesting a synergistic effect of sunlight and these parameters to damage E. coli. To increase the efficiency of the elimination of waterborne bacteria, the use of maturation ponds with intermediate depths (0.4m) would be advisable in view of the high temperatures and thus evaporation recorded in sahelian regions.

  10. Does occupational exposure to ionizing radiation induce adaptation

    International Nuclear Information System (INIS)

    Djurovic, B.; Selakovic, V.; Radjen, S.; Radakovic, S.; Spasic-Jokic, V.

    2008-01-01

    Full text: Even the most of personnel occupationally exposed (OE) to ionizing radiation (IR) is exposed to very low doses (LD), some harmful effects can be noticed. IR can affect the cell structure in two ways: directly and indirectly-inducing radiolysis of water and production of reactive oxygen species (ROS) similar to endogenously induced. In the low- LET exposure almost 70 % of absorbed energy is spent for ROS production. Over-production of ROS can cause oxidative stress. DNA is the main target of induced ROS. It is also experimentally showed that many important cell protective mechanisms, such is adaptation, are dependent of ROS concentration produced by low doses. The aim of this paper is to investigate if occupational exposure to LD induce over-production of ROS, and influence the activity of protective enzymes and radiosensitivity as well as induce adaptation. Our subjects were medical workers occupationally exposed to IR (44) and not-exposed (33), matched in gender, age, habits-dietary, alcohol consumption, smoking. Occupational exposure was calculated on the basis of individual TL-dose records. Besides the standard medical examination, micronucleus test, superoxide production and lipid peroxidation index, expressed as malonaldehyde (MDA) production, were performed by standard procedures as well as measurements of activity of the superoxide dismutase (SOD) and glutathione (GSH). Half of each sample were put in a sterile plastic test-tube placed in a plexiglas container 15 x 15 cm, and irradiated by 60 Co source of γ-ray at room temperature. Employed radiation dose was 2 Gy, dose-rate 0.45 Gy/min and distance from the source 74 cm. All blood samples were frozen at -70 C degrees, and kept till analyses which were performed at the same time. Our results confirm: significantly higher incidence of micronuclei in OE (.31±10 vs 17±8, p=0.00) with significant increase after irradiation in each group and lack of differences in radiosensitivity between groups

  11. Concentrated sunlight for organic solar cells

    DEFF Research Database (Denmark)

    Tromholt, Thomas

    2010-01-01

    . A high solar intensity study of inverted P3HT:PCBM solar cells is presented. Performance peak positions were found to be in the range of 1-5 suns, with smaller cells peaking at higher solar concentrations. Additionally, concentrated sunlight is demonstrated as a practical tool for accelerated stability...... were degraded resulting in acceleration factors in the range of 19-55. This shows that concentrated sunlight can be used as qualitatively to determine the lifetime of polymers under highly accelerated conditions....

  12. Exposure to arousal-inducing sounds facilitates visual search.

    Science.gov (United States)

    Asutay, Erkin; Västfjäll, Daniel

    2017-09-04

    Exposure to affective stimuli could enhance perception and facilitate attention via increasing alertness, vigilance, and by decreasing attentional thresholds. However, evidence on the impact of affective sounds on perception and attention is scant. Here, a novel aspect of affective facilitation of attention is studied: whether arousal induced by task-irrelevant auditory stimuli could modulate attention in a visual search. In two experiments, participants performed a visual search task with and without auditory-cues that preceded the search. Participants were faster in locating high-salient targets compared to low-salient targets. Critically, search times and search slopes decreased with increasing auditory-induced arousal while searching for low-salient targets. Taken together, these findings suggest that arousal induced by sounds can facilitate attention in a subsequent visual search. This novel finding provides support for the alerting function of the auditory system by showing an auditory-phasic alerting effect in visual attention. The results also indicate that stimulus arousal modulates the alerting effect. Attention and perception are our everyday tools to navigate our surrounding world and the current findings showing that affective sounds could influence visual attention provide evidence that we make use of affective information during perceptual processing.

  13. Visualization of DNA clustered damage induced by heavy ion exposure

    International Nuclear Information System (INIS)

    Tomita, M.; Yatagai, F.

    2003-01-01

    Full text: DNA double-strand breaks (DSBs) are the most lethal damage induced by ionizing radiations. Accelerated heavy-ions have been shown to induce DNA clustered damage, which is two or more DNA lesions induced within a few helical turns. Higher biological effectiveness of heavy-ions could be provided predominantly by induction of complex DNA clustered damage, which leads to non-repairable DSBs. DNA-dependent protein kinase (DNA-PK) is composed of catalytic subunit (DNA-PKcs) and DNA-binding heterodimer (Ku70 and Ku86). DNA-PK acts as a sensor of DSB during non-homologous end-joining (NHEJ), since DNA-PK is activated to bind to the ends of double-stranded DNA. On the other hand, NBS1 and histone H2AX are essential for DSB repair by homologous recombination (HR) in higher vertebrate cells. Here we report that phosphorylated H2AX at Ser139 (named γ-H2AX) and NBS1 form large undissolvable foci after exposure to accelerated Fe ions, while DNA-PKcs does not recognize DNA clustered damage. NBS1 and γ-H2AX colocalized with forming discrete foci after exposure to X-rays. At 0.5 h after Fe ion irradiation, NBS1 and γ-H2AX also formed discrete foci. However, at 3-8 h after Fe ion irradiation, highly localized large foci turned up, while small discrete foci disappeared. Large NBS1 and γ-H2AX foci were remained even 16 h after irradiation. DNA-PKcs recognized Ku-binding DSB and formed foci shortly after exposure to X-rays. DNA-PKcs foci were observed 0.5 h after 5 Gy of Fe ion irradiation and were almost completely disappeared up to 8 h. These results suggest that NBS1 and γ-H2AX can be utilized as molecular marker of DNA clustered damage, while DNA-PK selectively recognizes repairable DSBs by NHEJ

  14. Why We Need More Nature at Work: Effects of Natural Elements and Sunlight on Employee Mental Health and Work Attitudes.

    Science.gov (United States)

    An, Mihyang; Colarelli, Stephen M; O'Brien, Kimberly; Boyajian, Melanie E

    2016-01-01

    This study investigated the effects of natural elements and direct and indirect sunlight exposure on employee mental health and work attitudes. We recruited participants via an online panel from the United States and India, and analyzed data from 444 employees. Natural elements and sunlight exposure related positively to job satisfaction and organizational commitment, and negatively to depressed mood and anxiety. Direct sunlight was a dominant predictor of anxiety; indirect sunlight was a dominant predictor of depressed mood, job satisfaction, and organizational commitment. Natural elements buffered the relationship between role stressors and job satisfaction, depressed mood, and anxiety. We also found that depressed mood partially mediated the relationship between natural elements and job satisfaction. We discuss scientific and policy implications of these findings.

  15. Why We Need More Nature at Work: Effects of Natural Elements and Sunlight on Employee Mental Health and Work Attitudes

    Science.gov (United States)

    An, Mihyang; Colarelli, Stephen M.; O'Brien, Kimberly; Boyajian, Melanie E.

    2016-01-01

    This study investigated the effects of natural elements and direct and indirect sunlight exposure on employee mental health and work attitudes. We recruited participants via an online panel from the United States and India, and analyzed data from 444 employees. Natural elements and sunlight exposure related positively to job satisfaction and organizational commitment, and negatively to depressed mood and anxiety. Direct sunlight was a dominant predictor of anxiety; indirect sunlight was a dominant predictor of depressed mood, job satisfaction, and organizational commitment. Natural elements buffered the relationship between role stressors and job satisfaction, depressed mood, and anxiety. We also found that depressed mood partially mediated the relationship between natural elements and job satisfaction. We discuss scientific and policy implications of these findings. PMID:27214041

  16. Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Minicucci, Marcos; Oliveira, Fernando; Santos, Priscila; Polegato, Bertha; Roscani, Meliza; Fernandes, Ana Angelica; Lustosa, Beatriz; Paiva, Sergio; Zornoff, Leonardo; Azevedo, Paula, E-mail: paulasa@fmb.unesp.br [Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, São Paulo, SP (Brazil)

    2016-05-15

    Tobacco smoke exposure is an important risk factor for cardiac remodeling. Under this condition, inflammation, oxidative stress, energy metabolism abnormalities, apoptosis, and hypertrophy are present. Pentoxifylline has anti‑inflammatory, anti-apoptotic, anti-thrombotic and anti-proliferative properties. The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking. Wistar rats were distributed in four groups: Control (C), Pentoxifylline (PX), Tobacco Smoke (TS), and PX-TS. After two months, echocardiography, invasive blood pressure measurement, biochemical, and histological studies were performed. The groups were compared by two-way ANOVA with a significance level of 5%. TS increased left atrium diameter and area, which was attenuated by PX. In the isolated heart study, TS lowered the positive derivate (+dp/dt), and this was attenuated by PX. The antioxidants enzyme superoxide dismutase and glutathione peroxidase were decreased in the TS group; PX recovered these activities. TS increased lactate dehydrogenase (LDH) and decreased 3-hydroxyacyl Coenzyme A dehydrogenases (OH-DHA) and citrate synthase (CS). PX attenuated LDH, 3-OH-DHA and CS alterations in TS-PX group. TS increased IL-10, ICAM-1, and caspase-3. PX did not influence these variables. TS induced cardiac remodeling, associated with increased inflammation, oxidative stress, apoptosis, and changed energy metabolism. PX attenuated cardiac remodeling by reducing oxidative stress and improving cardiac bioenergetics, but did not act upon cardiac cytokines and apoptosis.

  17. One week's holiday sun exposure induces expression of photoaging biomarkers.

    Science.gov (United States)

    Lesiak, Aleksandra; Rogowski-Tylman, Michal; Danilewicz, Marian; Wozniacka, Anna; Narbutt, Joanna

    2016-01-01

    Skin aging is accompanied by the upregulation of the expression of various matrix metalloproteinases (MMPs). It was shown that exposure to ultraviolet radiation (UVR) may induce skin expression of MMPs and dysregulation of the transforming growth factor beta (TGF-β)/Smad pathway. The aim of our study was to compare the effects of short holiday UVR exposure and lifetime UVR exposure, on the expression of MMP-8, TGF-β1, and Smad2 in human skin biopsies. Skin biopsies were taken from the outer upper arm of 15 elderly people with significant photoaging (mean age 64.1 years) (Group 1) and from 15 healthy young adult volunteers (mean age 24.1 y) who participated in a six-day sun holiday. Biopsies were taken twice: 24 hours before leaving for holiday (Group 2a) and 24 hours after returning (Group 2b). The expression of TGF-β1, Smad2, and MMP-8 was examined by immunochemistry and measured semiquantitatively by two independent pathologists. The mean expression of TGF-β1 in dermal fibroblasts and keratinocytes in Group 1 and Group 2b was significantly lower than in Group 2a (0.54% ± 0.44% and 0.48% ± 0.51% vs. 1.48% ± 0.72%, respectively). The percentage of Smad2 (+) cells in Group 1 and Group 2b was lower than in Group 2a (2.13% ± 1.39% and 1.81% ± 1.16% vs. 4.13% ± 1.58%, respectively). The MMP-8 expression in Group 2b was 1.36% ± 0.68% and was significantly higher than in Group 1 (0.34% ± 0.42%) and Group 2a in which the protein was not detected (p < 0.001). We conclude that the decrease in the expression of TGF-β1 and Smad2 is a persistent biomarker of skin photoaging, while the increased expression of MMP-8 in keratinocytes can be regarded as a marker of acute sun exposure.

  18. Nocturnal light pollution and underexposure to daytime sunlight: Complementary mechanisms of circadian disruption and related diseases.

    Science.gov (United States)

    Smolensky, Michael H; Sackett-Lundeen, Linda L; Portaluppi, Francesco

    2015-01-01

    Routine exposure to artificial light at night (ALAN) in work, home, and community settings is linked with increased risk of breast and prostate cancer (BC, PC) in normally sighted women and men, the hypothesized biological rhythm mechanisms being frequent nocturnal melatonin synthesis suppression, circadian time structure (CTS) desynchronization, and sleep/wake cycle disruption with sleep deprivation. ALAN-induced perturbation of the CTS melatonin synchronizer signal is communicated maternally at the very onset of life and after birth via breast or artificial formula feedings. Nighttime use of personal computers, mobile phones, electronic tablets, televisions, and the like--now epidemic in adolescents and adults and highly prevalent in pre-school and school-aged children--is a new source of ALAN. However, ALAN exposure occurs concomitantly with almost complete absence of daytime sunlight, whose blue-violet (446-484 nm λ) spectrum synchronizes the CTS and whose UV-B (290-315 nm λ) spectrum stimulates vitamin D synthesis. Under natural conditions and clear skies, day/night and annual cycles of UV-B irradiation drive corresponding periodicities in vitamin D synthesis and numerous bioprocesses regulated by active metabolites augment and strengthen the biological time structure. Vitamin D insufficiency and deficiency are widespread in children and adults in developed and developing countries as a consequence of inadequate sunlight exposure. Past epidemiologic studies have focused either on exposure to too little daytime UV-B or too much ALAN, respectively, on vitamin D deficiency/insufficiency or melatonin suppression in relation to risk of cancer and other, e.g., psychiatric, hypertensive, cardiac, and vascular, so-called, diseases of civilization. The observed elevated incidence of medical conditions the two are alleged to influence through many complementary bioprocesses of cells, tissues, and organs led us to examine effects of the totality of the artificial light

  19. Natural sunlight shapes crude oil-degradingbacterial communities in northern Gulf of Mexico surface waters

    Directory of Open Access Journals (Sweden)

    Hernando P Bacosa

    2015-12-01

    Full Text Available Following the Deepwater Horizon (DWH spill in 2010, an enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico. Surface waters are characterized by intense sunlight and high temperature during summer. While the oil-degrading bacterial communities in the deep-sea plume have been widely investigated, the effect of natural sunlight on those in oil polluted surface waters remains unexplored to date. In this study, we incubated surface water from the DWH site with amendments of crude oil, Corexit dispersant, or both for 36 d under natural sunlight in the northern Gulf of Mexico. The bacterial community was analyzed over time for total abundance, density of alkane and polycyclic aromatic hydrocarbon degraders, and community composition via pyrosequencing. Our results showed that, for treatments with oil and/or Corexit, sunlight significantly reduced bacterial diversity and evenness and was a key driver of shifts in bacterial community structure. In samples containing oil or dispersant, sunlight greatly reduced abundance of the Cyanobacterium Synechococcus but increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Bartonella, and Halomonas. Dark samples with oil were represented by members of Thalassobius, Winogradskyella, Alcanivorax, Formosa, Pseudomonas, Eubacterium, Erythrobacter, Natronocella, and Coxiella. Both oil and Corexit inhibited the Candidatus Pelagibacter with or without sunlight exposure. For the first time, we demonstrated the effects of light in structuring microbial communities in water with oil and/or Corexit. Overall, our findings improve understanding of oil pollution in surface water, and provide unequivocal evidence that sunlight is a key factor in determining bacterial community composition and dynamics in oil polluted marine waters.

  20. Natural Sunlight Shapes Crude Oil-Degrading Bacterial Communities in Northern Gulf of Mexico Surface Waters.

    Science.gov (United States)

    Bacosa, Hernando P; Liu, Zhanfei; Erdner, Deana L

    2015-01-01

    Following the Deepwater Horizon (DWH) spill in 2010, an enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico. Surface waters are characterized by intense sunlight and high temperature during summer. While the oil-degrading bacterial communities in the deep-sea plume have been widely investigated, the effect of natural sunlight on those in oil polluted surface waters remains unexplored to date. In this study, we incubated surface water from the DWH site with amendments of crude oil, Corexit dispersant, or both for 36 days under natural sunlight in the northern Gulf of Mexico. The bacterial community was analyzed over time for total abundance, density of alkane and polycyclic aromatic hydrocarbon degraders, and community composition via pyrosequencing. Our results showed that, for treatments with oil and/or Corexit, sunlight significantly reduced bacterial diversity and evenness and was a key driver of shifts in bacterial community structure. In samples containing oil or dispersant, sunlight greatly reduced abundance of the Cyanobacterium Synechococcus but increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Bartonella, and Halomonas. Dark samples with oil were represented by members of Thalassobius, Winogradskyella, Alcanivorax, Formosa, Pseudomonas, Eubacterium, Erythrobacter, Natronocella, and Coxiella. Both oil and Corexit inhibited the Candidatus Pelagibacter with or without sunlight exposure. For the first time, we demonstrated the effects of light in structuring microbial communities in water with oil and/or Corexit. Overall, our findings improve understanding of oil pollution in surface water, and provide unequivocal evidence that sunlight is a key factor in determining bacterial community composition and dynamics in oil polluted marine waters.

  1. Bleaching of the thermoluminescence of feldspars by sunlight

    International Nuclear Information System (INIS)

    Robertson, G.B.; Prescott, J.R.; Hutton, J.T.

    1991-01-01

    Feldspars are an important component of materials used for thermoluminescence (TL) and photoluminescence (PL) dating of sediments; and successful dating implies a knowledge of the degree of re-setting by exposure to sunlight of the stored luminescence energy. We have studied the bleaching by full sunlight of the TL of six alkali feldspars of representative composition and of one oligoclase. The high potassium and high sodium feldspars are the brightest, and are also the least easily bleached, whereas those of intermediate (K-Na) composition bleach quickly. On a time scale of upwards of 16 h, all samples would have bleached enough for them to be useful for TL dating. A search was made for individual glow curve peaks that bleach particularly quickly (and are thus similar to the well-known 325 o C peak used in the TL dating of quartz). In the samples studied, there was only one glow curve peak that was selectively susceptible to bleaching: the 280 o C peak in oligoclase. (author)

  2. Genotoxic action of sunlight upon Bacillus subtilis spores: monitoring studies at Tokyo, Japan.

    Science.gov (United States)

    Munakata, N

    1989-12-01

    Samples of Bacillus subtilis spores dried on membrane filter were exposed to natural sunlight from solar-noon time at Tokyo. The survival and mutation induction of wild-type (UVR) and repair-deficient (UVS) spores were determined on 66 occasions since 1979. Two of the values were considered to be useful in monitoring solar UV intensity; the inverse of the time (in minutes) of exposure to kill 63% of the UVS spores ("sporocidal index") and the induced mutation frequency at 60 minutes of exposure of the UVR spores ("mutagenic index"). Both values were varied greatly due to time of a year, weather and other conditions. Estimates of year-round changes under clear skies were obtained by connecting the maximum values attained in these years. In these curves, there are more than 7-fold differences in the genotoxicity between winter and summer months, with major increases observed in early spring and decreases through autumn. Using a series of UV cut-off filters, the wavelengths most effective for the sporocidal actions were estimated to be in the range of 308-325 nm, shorter wavelengths being effective when the genotoxicity was higher. Sunburn meter of Robertson-Berger type seems to respond to slightly longer wavelength components of the solar spectrum. However, a reasonable correlation was obtained between the reading of the meter and the sporocidal index.

  3. Vitamin D, Sunlight and Prostate Cancer Risk

    Directory of Open Access Journals (Sweden)

    Krishna Vanaja Donkena

    2011-01-01

    Full Text Available Prostate cancer is the second common cancer in men worldwide. The prevention of prostate cancer remains a challenge to researchers and clinicians. Here, we review the relationship of vitamin D and sunlight to prostate cancer risk. Ultraviolet radiation of the sunlight is the main stimulator for vitamin D production in humans. Vitamin D's antiprostate cancer activities may be involved in the actions through the pathways mediated by vitamin D metabolites, vitamin D metabolizing enzymes, vitamin D receptor (VDR, and VDR-regulated genes. Although laboratory studies including the use of animal models have shown that vitamin D has antiprostate cancer properties, whether it can effectively prevent the development and/or progression of prostate cancer in humans remains to be inconclusive and an intensively studied subject. This review will provide up-to-date information regarding the recent outcomes of laboratory and epidemiology studies on the effects of vitamin D on prostate cancer prevention.

  4. Degadation of semiconducting polymers by concentrated sunlight

    DEFF Research Database (Denmark)

    Tromholt, Thomas; Manceau, Matthieu; Petersen, Martin Helgesen

    2011-01-01

    infra-red spectra of MEH-PPV degraded at 1 sun intensity and at high solar concentration only showed minor deviations in degradation mechanisms. The acceleration factor was found to vary linearly with the solar concentration. Finally, a comparison of the degradation rates at 1 sun and 100 suns...... was carried out in a materials study employing five different conjugated polymers relevant to polymer solar cells for which acceleration factors in the range 19–55 were obtained.......A lens based sunlight concentration setup was used to accelerate the degradation of semiconducting polymers. Sunlight was collected outdoor and focused into an optical fiber bundle allowing for indoor experimental work. Photo-degradation of several polymers was studied by UV–vis absorbance...

  5. Colour Counts: Sunlight and Skin Type as Drivers of Vitamin D Deficiency at UK Latitudes.

    Science.gov (United States)

    Webb, Ann R; Kazantzidis, Andreas; Kift, Richard C; Farrar, Mark D; Wilkinson, Jack; Rhodes, Lesley E

    2018-04-07

    Sunlight exposure, with resulting cutaneous synthesis, is a major source of vitamin D for many, while dietary intake is low in modern diets. The constitutive pigment in skin determines skin type, observed as white, brown, or black skin. The melanin pigment absorbs ultraviolet radiation (UVR) and protects underlying skin from damage caused by UVR. It also reduces the UVR available for vitamin D synthesis in the skin. It has been shown that the white-skinned population of the UK are able to meet their vitamin D needs with short, daily lunchtime exposures to sunlight. We have followed the same methodology, based on a 10-year UK all-weather UVR climatology, observation (sun exposure, diet, vitamin D status), and UVR intervention studies with Fitzpatrick skin type V (brown) adults, to determine whether sunlight at UK latitudes could provide an adequate source of vitamin D for this section of the population. Results show that to meet vitamin D requirements, skin type V individuals in the UK need ~25 min daily sunlight at lunchtime, from March to September. This makes several assumptions, including that forearms and lower legs are exposed June-August; only exposing hands and face at this time is inadequate. For practical and cultural reasons, enhanced oral intake of vitamin D should be considered for this population.

  6. Colour Counts: Sunlight and Skin Type as Drivers of Vitamin D Deficiency at UK Latitudes

    Directory of Open Access Journals (Sweden)

    Ann R. Webb

    2018-04-01

    Full Text Available Sunlight exposure, with resulting cutaneous synthesis, is a major source of vitamin D for many, while dietary intake is low in modern diets. The constitutive pigment in skin determines skin type, observed as white, brown, or black skin. The melanin pigment absorbs ultraviolet radiation (UVR and protects underlying skin from damage caused by UVR. It also reduces the UVR available for vitamin D synthesis in the skin. It has been shown that the white-skinned population of the UK are able to meet their vitamin D needs with short, daily lunchtime exposures to sunlight. We have followed the same methodology, based on a 10-year UK all-weather UVR climatology, observation (sun exposure, diet, vitamin D status, and UVR intervention studies with Fitzpatrick skin type V (brown adults, to determine whether sunlight at UK latitudes could provide an adequate source of vitamin D for this section of the population. Results show that to meet vitamin D requirements, skin type V individuals in the UK need ~25 min daily sunlight at lunchtime, from March to September. This makes several assumptions, including that forearms and lower legs are exposed June–August; only exposing hands and face at this time is inadequate. For practical and cultural reasons, enhanced oral intake of vitamin D should be considered for this population.

  7. Sunlight stability and rain-fastness of formulations of Baculovirus heliothis

    International Nuclear Information System (INIS)

    Ignoffo, C.M.; Garcia, C.; Saathoff, S.G.

    1997-01-01

    Sunlight-Ultraviolet, with an activity spectrum from 290 to 400 nm, is the most destructive factor affecting the persistence of baculoviruses. Benzopurpurin (a disazo dye) and carbon provided the best protection when polyhedral inclusion bodies (PIB) of Baculovirus heliothis were exposed to an artificial spectrum simulating sunlight-UV (UV). Greater than 75% of the original PIB activity was still present after 48 h of sunlight-UV. When sprayed on soybeans and exposed to natural sunlight, only formulations with carbon provided significant protection of PIB. The half-life of formulations were PIB-only 4.9 +/- 1.4 h (mean +/- SE), PIB + polymer (pyrrolidone-based sticker) 3.3 +/- 0.6 h, PIB + polymer + benzopurpurin 3.4 +/- 0.7 h, and PIB + polymer + carbon 27.7 +/- 5.2 h. PIB of B. heliothis tenaciously adhere to soybean, Glycine max (L.) Merrill, leaflets after spraying and drying. Less than 6% of the PIB activity of nonformulated PIB was lost after a drenching, simulated rainfall. More than 97% of the original PIB activity of carbon formulations was still present on soybean leaflets after 10 h of exposure to sunlight-UV. In contrast, 20% was present for formulations without carbon

  8. In Vivo Lipopolysaccharide Exposure of Human Blood Leukocytes Induces Cross-Tolerance to Multiple TLR Ligands

    NARCIS (Netherlands)

    de Vos, Alex F.; Pater, Jennie M.; van den Pangaart, Petra S.; de Kruif, Martijn D.; van 't Veer, Cornelis; van der Poll, Tom

    2009-01-01

    In vitro and in vivo experiments in mice have shown that exposure of cells to the TLR4 ligand LPS induces tolerance toward a second exposure to LPS and induces cross-tolerance to certain other TLR ligands. Recently, we found that LPS tolerance in experimental human endotoxemia and Gram-negative

  9. Persistence of Bacteroides ovatus under simulated sunlight irradiation

    KAUST Repository

    Dong, Shengkun

    2014-07-04

    Background: Bacteroides ovatus, a member of the genus Bacteroides, is considered for use in molecular-based methods as a general fecal indicator. However, knowledge on its fate and persistence after a fecal contamination event remains limited. In this study, the persistence of B. ovatus was evaluated under simulated sunlight exposure and in conditions similar to freshwater and seawater. By combining propidium monoazide (PMA) treatment and quantitative polymerase chain reaction (qPCR) detection, the decay rates of B. ovatus were determined in the presence and absence of exogenous photosensitizers and in salinity up to 39.5 parts per thousand at 27°C. Results: UVB was found to be important for B. ovatus decay, averaging a 4 log10 of decay over 6 h of exposure without the presence of extracellular photosensitizers. The addition of NaNO2, an exogenous sensitizer producing hydroxyl radicals, did not significantly change the decay rate of B. ovatus in both low and high salinity water, while the exogenous sensitizer algae organic matter (AOM) slowed down the decay of B. ovatus in low salinity water. At seawater salinity, the decay rate of B. ovatus was slower than that in low salinity water, except when both NaNO2 and AOM were present. Conclusion: The results of laboratory experiments suggest that if B. ovatus is released into either freshwater or seawater environment in the evening, 50% of it may be intact by the next morning; if it is released at noon, only 50% may be intact after a mere 5 min of full spectrum irradiation on a clear day. This study provides a mechanistic understanding to some of the important environmental relevant factors that influenced the inactivation kinetics of B. ovatus in the presence of sunlight irradiation, and would facilitate the use of B. ovatus to indicate the occurrence of fecal contamination.

  10. Sunlight persistence and rainfastness of spray-dried formulations of baculovirus isolated from Anagrapha falcifera (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Tamez-Guerra, P; McGuire, M R; Behle, R W; Hamm, J J; Sumner, H R; Shasha, B S

    2000-04-01

    Nuclear polyhedrosis viruses such as the one isolated from the celery looper, Anagrapha falcifera (Kirby) (AfMNPV), have the potential to be successful bioinsecticides if improved formulations can prevent rapid loss of insecticidal activity from environmental conditions such as sunlight and rainfall. We tested 16 spray-dried formulations of AfMNPV to determine the effect of different ingredients (e.g., lignin, corn flour, and so on) on insecticidal activity after simulated rain and simulated sunlight (at Peoria, IL) and natural sunlight exposures (at Tifton, GA). The most effective formulation contained pregelatinized corn flour and potassium lignate, which retained more than half of its original activity after 5 cm of simulated rain, and almost full activity after 8 h of simulated sunlight. In Georgia, formulations made with and without lignin were compared for persistence of insecticidal activity when exposed to natural sunlight. In addition, the effect of fluorescent brighteners as formulation components and spray tank additives was tested. Results showed that the formulations with lignin had more insecticidal activity remaining after sunlight exposure than formulations without lignin. The inclusion of brighteners in the formulation did not improve initial activity or virus persistence. However, a 1% tank mix significantly enhanced activity and improved persistence. Scanning electron micrographs revealed discreet particles, and transmission electron micrographs showed virus embedded within microgranules. Results demonstrated that formulations made with natural ingredients could improve persistence of virus-based biopesticides.

  11. Air Ambient-Operated pNIPAM-Based Flexible Actuators Stimulated by Human Body Temperature and Sunlight.

    Science.gov (United States)

    Yamamoto, Yuki; Kanao, Kenichiro; Arie, Takayuki; Akita, Seiji; Takei, Kuniharu

    2015-05-27

    Harnessing a natural power source such as the human body temperature or sunlight should realize ultimate low-power devices. In particular, macroscale and flexible actuators that do not require an artificial power source have tremendous potential. Here we propose and demonstrate electrically powerless polymer-based actuators operated at ambient conditions using a packaging technique in which the stimulating power source is produced by heat from the human body or sunlight. The actuating angle, force, and reliability are discussed as functions of temperature and exposure to sunlight. Furthermore, a wearable device platform and a smart curtain actuated by the temperature of human skin and sunlight, respectively, are demonstrated as the first proof-of-concepts. These nature-powered actuators should realize a new class of ultimate low-power devices.

  12. Effect of storage temperature and sunlight exposure on the ...

    African Journals Online (AJOL)

    Physicochemical properties (pH, Electrical conductivity, Total dissolved salt, Cl- , F- , NO3- ,SO4-2, NH4+ and Chemical oxygen demand) of Sixteen brands bottled water in Kurdistan region-Iraq were analyzed using standard methods. The physicochemical properties of the bottled water measured in this work compared with ...

  13. Life-threatening motor vehicle crashes in bright sunlight

    OpenAIRE

    Redelmeier, Donald A.; Raza, Sheharyar

    2017-01-01

    Abstract Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight. This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estim...

  14. Traceable calibration of photovoltaic reference cells using natural sunlight

    Science.gov (United States)

    Müllejans, H.; Zaaiman, W.; Pavanello, D.; Dunlop, E. D.

    2018-02-01

    At the European Solar Test Installation (ESTI) photovoltaic (PV) reference cells are calibrated traceably to SI units via the World Radiometric Reference (WRR) using natural sunlight. The Direct Sunlight Method (DSM) is described in detail and the latest measurement results and an updated uncertainty budget are reported. These PV reference cells then provide a practical means for measuring the irradiance of natural or simulated sunlight during the calibration of other PV devices.

  15. Cathodic protection of carbon steel in natural seawater: Effect of sunlight radiation

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, Alessandro [Istituto per l' Energetica e le Interfasi, IENI - CNR, Milano, via Roberto Cozzi 53 20125 Milano (Italy)], E-mail: alessandro.benedetti@cnr.it; Magagnin, Luca [Dip. Chimica, Materiali e Ing. Chimica G. Natta, Politecnico di Milano, via Mancinelli 7, 20131 Milano (Italy); Passaretti, Francesca [Istituto per l' Energetica e le Interfasi IENI - CNR, Lecco, c.so Promessi Sposi 29, 23900 Lecco (Italy); Chelossi, Elisabetta; Faimali, Marco [Istituto di Scienze Marine, ISMAR- CNR - Via De Marini 6, 16149, Genova (Italy); Montesperelli, Giampiero [Universita di Roma - Tor Vergata, Dipartimento di Scienze e Tecnologie Chimiche, Via della Ricerca Scientifica 00133, Roma (Italy)

    2009-11-01

    Cathodic protection of metals in seawater is known to be influenced by chemical-physical parameters affecting cathodic processes (oxygen discharge, hydrogen evolution and calcareous deposit precipitation). In shallow seawater, these parameters are influenced by sunlight photoperiod and photosynthetic activity. The results presented here represent the first step in studies dedicated to cathodic protection in shallow photic seawater. This paper reports on carbon steel protected at -850 mV vs. Ag/AgCl (oxygen limiting current regime) in the presence of sunlight radiation but in the absence of biological and photosynthetic activity, the role of which deserves future research. Comparison of results obtained by exposing electrochemical cells to daylight cycles in both biologically inactivated natural seawater and in NaCl 3.5 wt.% solutions showed that sunlight affects current densities and that calcareous deposit interfere with light-currents effects. Sunlight radiation and induced heating of the solution have been separated, highlighting results not otherwise obvious: (1) observed current waves concomitant with sunlight radiation depend fundamentally on solar radiation, (2) solar radiation can determine current enhancements from early to late phases of aragonite crystal growth, (3) a three-day-old CaCO{sub 3} layer reduces but does not eliminate the amplitude of the current waves. Theoretical calculations for oxygen limiting currents and additional field tests showed that sunlight, rather than bulk solution heating, is the main cause of daily current enhancements. This was confirmed by polarizations performed at -850 and -1000 mV vs. Ag/AgCl (constant bulk temperature), during which the electrode was irradiated with artificial lighting. This test also confirmed O{sub 2} discharge to be the cathodic process involved. A mechanism of radiation conversion to heat in the oxygen diffusion layer region is proposed.

  16. DNA damage by ethylbenzenehydroperoxide formed from carcinogenic ethylbenzene by sunlight irradiation

    International Nuclear Information System (INIS)

    Toda, Chitose; Uchida, Takafumi; Midorikawa, Kaoru; Murata, Mariko; Hiraku, Yusuke; Okamoto, Yoshinori; Ueda, Koji; Kojima, Nakao; Kawanishi, Shosuke

    2003-01-01

    Ethylbenzene, widely used in human life, is a non-mutagenic carcinogen. Sunlight-irradiated ethylbenzene caused DNA damage in the presence of Cu 2+ , but unirradiated ethylbenzene did not. A Cu + -specific chelator bathocuproine inhibited DNA damage and catalase showed a little inhibitory effect. The scopoletin assay revealed that peroxides and H 2 O 2 were formed in ethylbenzene exposed to sunlight. These results suggest that Cu + and alkoxyl radical mainly participate in DNA damage, and H 2 O 2 partially does. When catalase was added, DNA damage at thymine and cytosine was inhibited. Ethylbenzenehydroperoxide, identified by GC/MS analysis, induced the formation of 8-oxo-7,8-dihydro-2 ' -deoxyguanosine and caused DNA damage at consecutive guanines, as observed with cumenehydroperoxide. Equimolar concentrations of H 2 O 2 and acetophenone were produced by the sunlight-irradiation of 1-phenylethanol, a further degraded product of ethylbenzene. These results indicate a novel pathway that oxidative DNA damage induced by the peroxide and H 2 O 2 derived from sunlight-irradiated ethylbenzene may lead to expression of the carcinogenicity

  17. Critical Duration of Exposure for Developmental Chlorpyrifos-Induced Neurobehavioral Toxicity

    OpenAIRE

    Sledge, Damiyon; Yen, Jerry; Morton, Terrell; Dishaw, Laura; Petro, Ann; Donerly, Susan; Linney, Elwood; Levin, Edward D.

    2011-01-01

    Developmental exposure of rats to the pesticide chlorpyrifos (CPF) causes persistent neurobehavioral impairment. In a parallel series of studies with zebrafish, we have also found persisting behavioral dysfunction after developmental CPF exposure. We have developed a battery of measures of zebrafish behavior, which are reliable and sensitive to toxicant-induced damage. This study determined the critical duration of developmental CPF exposure for causing persisting neurobehavioral effects. Tes...

  18. Cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice

    International Nuclear Information System (INIS)

    Zhang Lianzhen; Deng Zhicheng

    1993-01-01

    The cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice were studied. The results of this study showed that human lymphocytes in vitro and mouse marrow cells in vivo can become adapted to low-level irradiation from 3 H-TdR or exposure to a low dose of X-or γ-irradiation, so that they become less sensitive to the chromosomal damage effects of subsequent exposures. (4 tabs.)

  19. Disorders induced by direct occupational exposure to noise: Systematic review

    Directory of Open Access Journals (Sweden)

    Andrea Domingo-Pueyo

    2016-01-01

    Full Text Available Background: To review the available scientific literature about the effects on health by occupational exposure to noise. Materials and Methods: A systematic review of the retrieved scientific literature from the databases MEDLINE (via PubMed, ISI-Web of Knowledge (Institute for Scientific Information, Cochrane Library Plus, SCOPUS, and SciELO (collection of scientific journals was conducted. The following terms were used as descriptors and were searched in free text: “Noise, Occupational,” “Occupational Exposure,” and “Occupational Disease.” The following limits were considered: “Humans,” “Adult (more than 18 years,” and “Comparative Studies.” Results: A total of 281 references were retrieved, and after applying inclusion/exclusion criteria, 25 articles were selected. Of these selected articles, 19 studies provided information about hearing disturbance, four on cardiovascular disorders, one regarding respiratory alteration, and one on other disorders. Conclusions: It can be interpreted that the exposure to noise causes alterations in humans with different relevant outcomes, and therefore appropriate security measures in the work environment must be employed to minimize such an exposure and thereby to reduce the number of associated disorders.

  20. Fluoxetine treatment ameliorates depression induced by perinatal arsenic exposure via a neurogenic mechanism

    Science.gov (United States)

    Tyler, Christina R.; Solomon, Benjamin R.; Ulibarri, Adam L.; Allan, Andrea M.

    2014-01-01

    Several epidemiological studies have reported an association between arsenic exposure and increased rates of psychiatric disorders, including depression, in exposed populations. We have previously demonstrated that developmental exposure to low amounts of arsenic induces depression in adulthood along with several morphological and molecular aberrations, particularly associated with the hippocampus and the hypothalamic–pituitary–adrenal (HPA) axis. The extent and potential reversibility of this toxin-induced damage has not been characterized to date. In this study, we assessed the effects of fluoxetine, a selective serotonin reuptake inhibitor antidepressant, on adult animals exposed to arsenic during development. Perinatal arsenic exposure (PAE) induced depressive-like symptoms in a mild learned helplessness task and in the forced swim task after acute exposure to a predator odor (2,4,5-trimethylthiazoline, TMT). Chronic fluoxetine treatment prevented these behaviors in both tasks in arsenic-exposed animals and ameliorated arsenic-induced blunted stress responses, as measured by corticosterone (CORT) levels before and after TMT exposure. Morphologically, chronic fluoxetine treatment reversed deficits in adult hippocampal neurogenesis (AHN) after PAE, specifically differentiation and survival of neural progenitor cells. Protein expression of BDNF, CREB, the glucocorticoid receptor (GR), and HDAC2 was significantly increased in the dentate gyrus of arsenic animals after fluoxetine treatment. This study demonstrates that damage induced by perinatal arsenic exposure is reversible with chronic fluoxetine treatment resulting in restored resiliency to depression via a neurogenic mechanism. PMID:24952232

  1. In Utero Estrogen Exposure Increases Antiestrogen Resistance by Inducing EMT

    Science.gov (United States)

    2015-02-01

    currently unclear. Our recent preclinical study found that maternal exposure to excess estrogens during pregnancy increases the risk that AE resistance in...References: 1. Hilakivi-Clarke L, Clarke R, Onojafe I, Raygada M, Cho E, Lippman M. A maternal diet high in n-6-polyunsaturated fats alters mammary...the rate of obesity in this country (high fat diets resulting in elevated circulating estrogen levels), the prevelance of bisphenol A in our drinking

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

    Science.gov (United States)

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

    2018-06-01

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

  3. Fate of kelthane residues on apple pomace exposed to drying in the dark, sunlight, and ultraviolet light irradiation

    International Nuclear Information System (INIS)

    Archer, T.E.; Toscano, R.A.

    1972-01-01

    The present investigations were undertaken to determine the fate of Kelthane residues intentionally applied to apples under controlled laboratory conditions and the reduction of these residues in the pomace by exposure to drying in the dark, in sunlight, and ultraviolet light irradiation

  4. Photolytic debromination pathway of polybrominated diphenyl ethers in hexane by sunlight

    International Nuclear Information System (INIS)

    Wei, Hua; Zou, Yonghong; Li, An; Christensen, Erik R.; Rockne, Karl J.

    2013-01-01

    The objective of this work is to identify the photolytic debromination pathways of polybrominated diphenyl ethers (PBDEs). Thirteen PBDEs (BDEs 209, 208, 207, 206, 196, 183, 154, 153, 100, 99, 85, 47 and 28) in hexane were individually exposed to sunlight for up to 64 h. A total of 180 PBDEs were screened and 74 BDE debromination products were detected. The disappearance rate constant increased exponentially with increasing number of bromines. While no evident difference in debromination preference among ortho, meta and para bromines was found for heavier congeners, the vulnerability rank order was meta ≥ ortho > para for the lighter congeners (≤8 Br). The total molar mass of PBDEs continuously decreased during sunlight exposure, indicating PBDEs were transformed to non-PBDE compounds. A stochastic least squares debromination pathway model was developed to simulate the reactions and determine the yields to extend the results beyond the experimental observations. -- Highlights: ► 74 PBDEs are identified as the products of debromination via photolysis. ► Debromination is more likely at meta than para positions for PBDEs with ≤8 bromines. ► The stochastic least squares model results agree with and expand the experimental observations. ► Mass imbalance indicates a significant loss of PBDE mass during sunlight exposure. -- The PBDE debromination products and pathways identified in this work will assist in future studies on their environmental fate

  5. Electrical Characterisation of electron beam exposure induced Defects in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Danga, Helga T., E-mail: helga.danga@up.ac.za; Auret, Francois D.; Coelho, Sergio M.M.; Diale, Mmantsae

    2016-01-01

    The defects introduced in epitaxially grown p-type silicon (Si) during electron beam exposure were electrically characterised using deep level transient spectroscopy (DLTS) and high resolution Laplace-DLTS. In this process, Si samples were first exposed to the conditions of electron beam deposition (EBD) without metal deposition. This is called electron beam exposure (EBE) herein. After 50 minutes of EBE, nickel (Ni) Schottky contacts were fabricated using the resistive deposition method. The defect level observed using the Ni contacts had an activation energy of H(0.55). This defect has an activation energy similar to that of the I-defect. The defect level is similar to that of the HB4, a boron related defect. DLTS depth profiling revealed that H(0.55) could be detected up to a depth of 0.8 μm below the junction. We found that exposing the samples to EBD conditions without metal deposition introduced a defect which was not introduced by the EBD method. We also observed that the damage caused by EBE extended deeper into the material compared to that caused by EBD.

  6. Temporal Stability of the Microbial Community in Sewage-Polluted Seawater Exposed to Natural Sunlight Cycles and Marine Microbiota

    Science.gov (United States)

    Sassoubre, Lauren M.; Yamahara, Kevan M.

    2015-01-01

    Billions of gallons of untreated wastewater enter the coastal ocean each year. Once sewage microorganisms are in the marine environment, they are exposed to environmental stressors, such as sunlight and predation. Previous research has investigated the fate of individual sewage microorganisms in seawater but not the entire sewage microbial community. The present study used next-generation sequencing (NGS) to examine how the microbial community in sewage-impacted seawater changes over 48 h when exposed to natural sunlight cycles and marine microbiota. We compared the results from microcosms composed of unfiltered seawater (containing naturally occurring marine microbiota) and filtered seawater (containing no marine microbiota) to investigate the effect of marine microbiota. We also compared the results from microcosms that were exposed to natural sunlight cycles with those from microcosms kept in the dark to investigate the effect of sunlight. The microbial community composition and the relative abundance of operational taxonomic units (OTUs) changed over 48 h in all microcosms. Exposure to sunlight had a significant effect on both community composition and OTU abundance. The effect of marine microbiota, however, was minimal. The proportion of sewage-derived microorganisms present in the microcosms decreased rapidly within 48 h, and the decrease was the most pronounced in the presence of both sunlight and marine microbiota, where the proportion decreased from 85% to 3% of the total microbial community. The results from this study demonstrate the strong effect that sunlight has on microbial community composition, as measured by NGS, and the importance of considering temporal effects in future applications of NGS to identify microbial pollution sources. PMID:25576619

  7. Treatment of phobophobia by exposure to CO2-induced anxiety symptoms.

    Science.gov (United States)

    Griez, E; van den Hout, M A

    1983-08-01

    It is argued that fear of fear, or phobophobia, can be an important maintaining factor in cases of seemingly free-floating anxiety with periodic panic attacks and that effective treatment consists of exposure to the feared neurovegetative sensations. The case history presented suggests that inhalation of CO2-O2 mixtures induces the phobic interoceptive sensations and that it can be used in the exposure treatment of phobophobia.

  8. Chronic inorganic mercury exposure induces sex-specific changes in central TNFα expression: Importance in autism?

    OpenAIRE

    Curtis, J. Thomas; Chen, Yue; Buck, Daniel J.; Davis, Randall L.

    2011-01-01

    Mercury is neurotoxic and increasing evidence suggests that environmental exposure to mercury may contribute to neuropathologies including Alzheimer's disease and autism spectrum disorders. Mercury is known to disrupt immunocompetence in the periphery, however, little is known about the effects of mercury on neuroimmune signaling. Mercury-induced effects on central immune function are potentially very important given that mercury exposure and neuroinflammation both are implicated in certain n...

  9. Nature sunlight bleaching of Ti center ESR signal in quartz

    International Nuclear Information System (INIS)

    Yin Gongming; Liu Chunru; Li Jianping; Fang Jiahu; Gao Lu; Lin Min

    2009-01-01

    Quartz grains were extracted from granite. Bleaching was carried out in four different area chosen for their different altitudes (Beijing, Yinchuan, Germu, Lhasa), in order to observe their behavior under different intensities of the UV (Ultra violet) component of sunlight. The result of our experiments indicate that the Ti center signal is totally bleachable by the natural sunlight and show that the Ti center signal was reduced to zero after about 128 h in Beijing and after 56 h for Lhasa. We can speculate that different intensity of the UV component of sunlight lead to different minimal time necessary to obtain the total bleaching of the quartz sample. (authors)

  10. Preconception paternal bisphenol A exposure induces sex-specific anxiety and depression behaviors in adult rats.

    Directory of Open Access Journals (Sweden)

    Ying Fan

    Full Text Available Bisphenol A (BPA, an environmental endocrine-disrupting compound, has drawn a great attention for its adverse effect on behavioral development. Maternal exposure to this compound has been reported to induce anxiety and depression in offspring, but the effect of its paternal exposure is rarely discussed. This study investigated whether preconception paternal BPA exposure can affect the emotions of male rats and their offspring. Eighteen adult male rats (F0 received either a vehicle or 50 μg/kg/day BPA diet for 21 weeks and were then mated with non-exposed females to produce offspring (F1. The affective behaviors of F0 and F1 rats were evaluated in the open-field test, the elevated-plus maze and the forced swimming test, and their serum corticosterone were then examined. BPA exposure induced increased anxiety behaviors along with increased serum corticosterone in F0 rats. This paternal exposure also led to increased anxiety behaviors in F1 females and aggravated depression behaviors in both sexes of F1 rats. Furthermore, only F1 females exhibited increased serum corticosterone. Overall, these data indicate that preconception paternal exposure to a low dose of BPA may induce transgenerational sex-specific impairments in the affection of adult rats.

  11. Lithium prevents long-term neural and behavioral pathology induced by early alcohol exposure.

    Science.gov (United States)

    Sadrian, B; Subbanna, S; Wilson, D A; Basavarajappa, B S; Saito, M

    2012-03-29

    Fetal alcohol exposure can cause developmental defects in offspring known as fetal alcohol spectrum disorder (FASD). FASD symptoms range from obvious facial deformities to changes in neuroanatomy and neurophysiology that disrupt normal brain function and behavior. Ethanol exposure at postnatal day 7 in C57BL/6 mice induces neuronal cell death and long-lasting neurobehavioral dysfunction. Previous work has demonstrated that early ethanol exposure impairs spatial memory task performance into adulthood and perturbs local and interregional brain circuit integrity in the olfacto-hippocampal pathway. Here we pursue these findings to examine whether lithium prevents anatomical, neurophysiological, and behavioral pathologies that result from early ethanol exposure. Lithium has neuroprotective properties that have been shown to prevent ethanol-induced apoptosis. Here we show that mice co-treated with lithium on the same day as ethanol exposure exhibit dramatically reduced acute neurodegeneration in the hippocampus and retain hippocampal-dependent spatial memory as adults. Lithium co-treatment also blocked ethanol-induced disruption in synaptic plasticity in slice recordings of hippocampal CA1 in the adult mouse brain. Moreover, long-lasting dysfunctions caused by ethanol in olfacto-hippocampal networks, including sensory-evoked oscillations and resting state coherence, were prevented in mice co-treated with lithium. Together, these results provide behavioral and physiological evidence that lithium is capable of preventing or reducing immediate and long-term deleterious consequences of early ethanol exposure on brain function. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats

    International Nuclear Information System (INIS)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen; Zhang, Jie; Shen, Heqing

    2017-01-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33 proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb cardiac contraction and relaxation, impair heart morphogenesis and development, and induce thrombosis in rats, which is mediated by the Akt/p38 MAPK signaling pathway. Overall, these findings will augment our knowledge of the involved mechanisms and develop useful biomarkers for cardiotoxicity induced by environmental arsenic exposure. - Highlights: • Arsenic exposure has been associated with a number of adverse health effects. • The molecular mechanisms involved in arsenic-induced cardiotoxicity remain unclear. • Differential proteins were identified in arsenic-exposed rat heart by proteomics. • Arsenic induces heart toxicity through the Akt/p38 MAPK signaling pathway. - Label-free quantitative proteomic analysis of rat heart reveals putative mechanisms and biomarkers for arsenic-induced cardiotoxicity.

  13. Exposure to radiofrequency radiation induces oxidative stress in duckweed Lemna minor L

    International Nuclear Information System (INIS)

    Tkalec, Mirta; Malaric, Kresimir; Pevalek-Kozlina, Branka

    2007-01-01

    patterns of antioxidative enzymes or HSP70 level were found between control and exposed plants. Our results showed that non-thermal exposure to investigated radiofrequency fields induced oxidative stress in duckweed as well as unspecific stress responses, especially of antioxidative enzymes. However, the observed effects markedly depended on the field frequencies applied as well as on other exposure parameters (strength, modulation and exposure time). Enhanced lipid peroxidation and H 2 O 2 content accompanied by diminished antioxidative enzymes activity caused by exposure to investigated EMFs, especially at 900 MHz, indicate that oxidative stress could partly be due to changed activities of antioxidative enzymes

  14. Holocaust Exposure Induced Intergenerational Effects on FKBP5 Methylation.

    Science.gov (United States)

    Yehuda, Rachel; Daskalakis, Nikolaos P; Bierer, Linda M; Bader, Heather N; Klengel, Torsten; Holsboer, Florian; Binder, Elisabeth B

    2016-09-01

    The involvement of epigenetic mechanisms in intergenerational transmission of stress effects has been demonstrated in animals but not in humans. Cytosine methylation within the gene encoding for FK506 binding protein 5 (FKBP5) was measured in Holocaust survivors (n = 32), their adult offspring (n = 22), and demographically comparable parent (n = 8) and offspring (n = 9) control subjects, respectively. Cytosine-phosphate-guanine sites for analysis were chosen based on their spatial proximity to the intron 7 glucocorticoid response elements. Holocaust exposure had an effect on FKBP5 methylation that was observed in exposed parents as well in their offspring. These effects were observed at bin 3/site 6. Interestingly, in Holocaust survivors, methylation at this site was higher in comparison with control subjects, whereas in Holocaust offspring, methylation was lower. Methylation levels for exposed parents and their offspring were significantly correlated. In contrast to the findings at bin 3/site 6, offspring methylation at bin 2/sites 3 to 5 was associated with childhood physical and sexual abuse in interaction with an FKBP5 risk allele previously associated with vulnerability to psychological consequences of childhood adversity. The findings suggest the possibility of site specificity to environmental influences, as sites in bins 3 and 2 were differentially associated with parental trauma and the offspring's own childhood trauma, respectively. FKBP5 methylation averaged across the three bins examined was associated with wake-up cortisol levels, indicating functional relevance of the methylation measures. This is the first demonstration of an association of preconception parental trauma with epigenetic alterations that is evident in both exposed parent and offspring, providing potential insight into how severe psychophysiological trauma can have intergenerational effects. Published by Elsevier Inc.

  15. Charles Burchfield: "October Wind and Sunlight in the Woods."

    Science.gov (United States)

    Fitzgerald, Gaynell

    1986-01-01

    Based on Charles Burchfield's watercolor, "October Wind and Sunlight in the Woods," the goal of this lesson is to introduce students in grades seven through nine to Burchfield's use of symbolism. (JDH)

  16. Analytic Models for Sunlight Charging of a Rapidly Spinning Satellite

    National Research Council Canada - National Science Library

    Tautz, Maurice

    2003-01-01

    ... photoelectrons can be blocked by local potential barriers. In this report, we discuss two analytic models for sunlight charging of a rapidly spinning spherical satellite, both of which are based on blocked photoelectron currents...

  17. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB.

    Directory of Open Access Journals (Sweden)

    Bao-Fei Sun

    Full Text Available High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g. was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF and phosphorylated cAMP-response element binding protein (pCREB in the CA1 and dentate gyrus areas (DG of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus.

  18. Biodegradation and photooxidation of crude oil under natural sunlight in the northern Gulf of Mexico

    Science.gov (United States)

    Bacosa, H. P.; Erdner, D.; Liu, Z.

    2016-02-01

    An enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico (nGoM) following the Deepwater Horizon (DWH) spill. While the oil degradation and bacterial communities in the deep-sea plume have been widely investigated, the effect of sunlight on oil and bacterial assemblages in surface waters have received less attention. In this study, we amended surface water collected near the DWH site with crude oil and/or Corexit dispersant and incubated under natural sunlight in the nGoM for 36 d in summer of 2013. The residual alkanes, polycyclic aromatic hydrocarbons (PAHs), and alkalyted PAHs were analyzed by GC-MS, and bacterial community was determined via pyrosequencing. The results show that n-alkane biodegradation rate constants (first order) were ca. ten-fold higher than the photooxidation rate constants. While biodegradation was characterized by a lag phase, photooxidation rate constants for the 2-3 ring and 4-5 ring PAHs, were 0.08-0.98 day-1 and 0.01-0.07 day-1, respectively. Compared to biodegradation, photooxidation increased the transformation of 4-5 ring PAHs by 70% and 3-4 ring alkylated PAHs by 36%. Sunlight significantly reduced bacterial diversity and a driver of shifts in bacterial community structure in oil and Corexit treatments. In amended treatments, sunlight increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Halomonas and Bartonella, while the dark treatments enriched Thalassobius, Winogradskyella, Alcanivorax, Formosa, Eubacterium, Erythrobacter, Natronocella, and Pseudomonas. This suggests that different bacteria are degrading the hydrocarbons in the dark and under light exposure. In a follow up study using DNA-Stable isotope probing (SIP), we identified the alkane and PAH degraders using 13C-labeled hexadecane and phenanthrene, respectively. The results of metagenomic and metatranscriptomic analyses in the light and dark incubations will be presented. For the first

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

    Science.gov (United States)

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

    2012-07-16

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

  20. Adaptive fluid lens and sunlight redirection system : exploring a novel way of redirecting and altering sunlight in large span roofs

    NARCIS (Netherlands)

    Heinzelmann, F.; Bristogianni, T.; Teuffel, P.; Stouffs, R.; Sariyildiz, S.

    2013-01-01

    The paper describes a novel system to alter and redirect sunlight under large span roofs with the help of a fluid lens system. Focus lies on the computational design, testing, measurement and evaluation of the performance of a physical prototype.

  1. Current densities in a pregnant woman model induced by simultaneous ELF electric and magnetic field exposure

    International Nuclear Information System (INIS)

    Cech, R; Leitgeb, N; Pediaditis, M

    2008-01-01

    The pregnant woman model SILVY was studied to ascertain to what extent the electric current densities induced by 50 Hz homogeneous electric and magnetic fields increase in the case of simultaneous exposure. By vectorial addition of the electric current densities, it could be shown that under worst case conditions the basic restrictions recommended by ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines are exceeded within the central nervous system (CNS) of the mother, whereas in sole field exposure they are not. However, within the foetus the induced current densities do not comply with basic restrictions, either from single reference-level electric fields or from simultaneous exposure to electric and magnetic fields. Basic limits were considerably exceeded

  2. Piracetam prevents memory deficit induced by postnatal propofol exposure in mice.

    Science.gov (United States)

    Wang, Yuan-Lin; Li, Feng; Chen, Xin

    2016-05-15

    Postnatal propofol exposure impairs hippocampal synaptic development and memory. However, the effective agent to alleviate the impairments was not verified. In this study, piracetam, a positive allosteric modulator of AMPA receptor was administered following a seven-day propofol regime. Two months after propofol administration, hippocampal long-term potentiation (LTP) and long-term memory decreased, while intraperitoneal injection of piracetam at doses of 100mg/kg and 50mg/kg following last propofol exposure reversed the impairments of memory and LTP. Mechanically, piracetam reversed propofol exposure-induced decrease of BDNF and phosphorylation of mTor. Similar as piracetam, BDNF supplementary also ameliorated propofol-induced abnormalities of synaptic plasticity-related protein expressions, hippocampal LTP and long-term memory. These results suggest that piracetam prevents detrimental effects of propofol, likely via activating BDNF synthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Inhalation exposure to ethylene induces eosinophilic rhinitis and nasal epithelial remodeling in Fischer 344 rats.

    Science.gov (United States)

    Brandenberger, Christina; Hotchkiss, Jon A; Krieger, Shannon M; Pottenger, Lynn H; Harkema, Jack R

    2015-11-05

    This study investigated the time- and concentration-dependent effects of inhaled ethylene on eosinophilic rhinitis and nasal epithelial remodeling in Fisher 344 rats exposed to 0, 10, 50, 300, or 10,000 ppm ethylene, 6 h/day, 5 days/week for up to 4 weeks. Morphometric quantitation of eosinophilic inflammation and mucous cell metaplasia/hyperplasia (MCM) and nasal mucosal gene expression were evaluated at anatomic sites previously shown to undergo ethylene-induced epithelial remodeling. Serum levels of total IgE, IgG1 and IgG2a were measured to determine if ethylene exposure increased the expression of Th2-associated (IgE and IgG1) relative to Th1-associated (IgG2a) antibody isotypes. Rats exposed to 0 or 10,000 ppm for 1, 3, 5, 10, or 20 days were analyzed to assess the temporal pattern of ethylene-induced alterations in nasal epithelial cell proliferation, morphology and gene expression. Rats exposed to 0, 10, 50, 300, and 10,000 ppm ethylene for 20 days were analyzed to assess concentration-dependent effects on lesion development. Additional rats exposed 4 weeks to 0, 300, or 10,000 ppm ethylene were held for 13 weeks post-exposure to examine the persistence of ethylene-induced mucosal alterations. The data indicate that cell death and reparative cell proliferation were not a part of the pathogenesis of ethylene-induced nasal lesions. Enhanced gene expression of Th2 cytokines (e.g., IL-5, IL-13) and chitinase (YM1/2) in the nasal mucosa was much greater than that of Th1 cytokines (e.g., IFNγ) after ethylene exposure. A significant increase in MCM was measured after 5 days of exposure to 10,000 ppm ethylene and after 20 days of exposure 10 ppm ethylene. Ethylene-induced MCM was reversible after cessation of exposure. No increase in total serum IgE, IgG1 or IgG2a was measured in any ethylene-exposed group. These data do not support involvement of an immune-mediated allergic mechanism in the pathogenesis of ethylene-induced nasal lesions in rats. Repeated

  4. Sunlight creates oxygenated species in water-soluble fractions of Deepwater horizon oil

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Phoebe Z. [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States); Chen, Huan [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Podgorski, David C. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Future Fuels Institute, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); McKenna, Amy M. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Tarr, Matthew A., E-mail: mtarr@uno.edu [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States)

    2014-09-15

    Graphical abstract: Sunlight oxygenates petroleum. - Highlights: • Oxidation seen in water-soluble oil fraction after exposure to simulated sunlight. • Oxygen addition occurred across a wide range of carbon number and DBE. • Oil compounds were susceptible to addition of multiple oxygens to each molecule. • Results provide understanding of fate of oil on water after exposure to sunlight. - Abstract: In order to assess the impact of sunlight on oil fate, Macondo well oil from the Deepwater Horizon (DWH) rig was mixed with pure water and irradiated with simulated sunlight. After irradiation, the water-soluble organics (WSO) from the dark and irradiated samples were extracted and characterized by ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Liquid–liquid extraction yielded two fractions from dark and irradiated water/oil mixtures: acidic WSOs (negative-ion electrospray (ESI)), and base/neutral WSOs (positive-ion ESI) coupled to FT-ICR MS to catalog molecular-level transformations that occur to Macondo-derived WSOs after solar irradiation. Such direct measure of oil phototransformation has not been previously reported. The most abundant heteroatom class detected in the irradiated WSO acid fractions correspond to molecules that contain five oxygens (O{sub 5}), while the most abundant acids in the dark samples contain two oxygen atoms per molecule (O{sub 2}). Higher-order oxygen classes (O{sub 5}–O{sub 9}) were abundant in the irradiated samples, but <1.5% relative abundance in the dark sample. The increased abundance of higher-order oxygen classes in the irradiated samples relative to the dark samples indicates that photooxidized components of the Macondo crude oil become water-soluble after irradiation. The base/neutral fraction showed decreased abundance of pyridinic nitrogen (N{sub 1}) concurrent with an increased abundance of N{sub 1}O{sub x} classes after irradiation. The predominance of higher

  5. Differential Immunotoxicity Induced by Two Different Windows of Developmental Trichloroethylene Exposure

    Directory of Open Access Journals (Sweden)

    Kathleen M. Gilbert

    2014-01-01

    Full Text Available Developmental exposure to environmental toxicants may induce immune system alterations that contribute to adult stage autoimmune disease. We have shown that continuous exposure of MRL+/+ mice to trichloroethylene (TCE from gestational day (GD 0 to postnatal day (PND 49 alters several aspects of CD4+ T cell function. This window of exposure corresponds to conception-adolescence/young adulthood in humans. More narrowly defining the window of TCE developmental exposure causes immunotoxicity that would establish the stage at which avoidance and/or intervention would be most effective. The current study divided continuous TCE exposure into two separate windows, namely, gestation only (GD0 to birth (PND0 and early-life only (PND0-PND49. The mice were examined for specific alterations in CD4+ T cell function at PND49. One potentially long-lasting effect of developmental exposure, alterations in retrotransposon expression indicative of epigenetic alterations, was found in peripheral CD4+ T cells from both sets of developmentally exposed mice. Interestingly, certain other effects, such as alterations in thymus cellularity, were only found in mice exposed to TCE during gestation. In contrast, expansion of memory/activation cell subset of peripheral CD4+ T cells were only found in mice exposed to TCE during early life. Different windows of developmental TCE exposure can have different functional consequences.

  6. Glufosinate aerogenic exposure induces glutamate and IL-1 receptor dependent lung inflammation.

    Science.gov (United States)

    Maillet, Isabelle; Perche, Olivier; Pâris, Arnaud; Richard, Olivier; Gombault, Aurélie; Herzine, Ameziane; Pichon, Jacques; Huaux, Francois; Mortaud, Stéphane; Ryffel, Bernhard; Quesniaux, Valérie F J; Montécot-Dubourg, Céline

    2016-11-01

    Glufosinate-ammonium (GLA), the active component of an herbicide, is known to cause neurotoxicity. GLA shares structural analogy with glutamate. It is a powerful inhibitor of glutamine synthetase (GS) and may bind to glutamate receptors. Since these potentials targets of GLA are present in lung and immune cells, we asked whether airway exposure to GLA may cause lung inflammation in mice. A single GLA exposure (1 mg/kg) induced seizures and inflammatory cell recruitment in the broncho-alveolar space, and increased myeloperoxidase (MPO), inducible NO synthase (iNOS), interstitial inflammation and disruption of alveolar septae within 6-24 h. Interleukin 1β (IL-1β) was increased and lung inflammation depended on IL-1 receptor 1 (IL-1R1). We demonstrate that glutamate receptor pathway is central, since the N-methyl-D-aspartate (NMDA) receptor inhibitor MK-801 prevented GLA-induced lung inflammation. Chronic exposure (0.2 mg/kg 3× per week for 4 weeks) caused moderate lung inflammation and enhanced airway hyperreactivity with significant increased airway resistance. In conclusion, GLA aerosol exposure causes glutamate signalling and IL-1R-dependent pulmonary inflammation with airway hyperreactivity in mice. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

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

    Science.gov (United States)

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

    2011-01-01

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

  8. Exposure to endocrine disruptor induces transgenerational epigenetic deregulation of microRNAs in primordial germ cells.

    Directory of Open Access Journals (Sweden)

    Miguel A Brieño-Enríquez

    Full Text Available In mammals, germ cell differentiation is initiated in the Primordial Germ Cells (PGCs during fetal development. Prenatal exposure to environmental toxicants such as endocrine disruptors may alter PGC differentiation, development of the male germline and induce transgenerational epigenetic disorders. The anti-androgenic compound vinclozolin represents a paradigmatic example of molecule causing transgenerational effects on germ cells. We performed prenatal exposure to vinclozolin in mice and analyzed the phenotypic and molecular changes in three successive generations. A reduction in the number of embryonic PGCs and increased rate of apoptotic cells along with decrease of fertility rate in adult males were observed in F1 to F3 generations. Blimp1 is a crucial regulator of PGC differentiation. We show that prenatal exposure to vinclozolin deregulates specific microRNAs in PGCs, such as miR-23b and miR-21, inducing disequilibrium in the Lin28/let-7/Blimp1 pathway in three successive generations of males. As determined by global maps of cytosine methylation, we found no evidence for prominent changes in DNA methylation in PGCs or mature sperm. Our data suggest that embryonic exposure to environmental endocrine disruptors induces transgenerational epigenetic deregulation of expression of microRNAs affecting key regulatory pathways of germ cells differentiation.

  9. Nicotine ameliorates schizophrenia-like cognitive deficits induced by maternal LPS exposure: a study in rats

    Directory of Open Access Journals (Sweden)

    Uta Waterhouse

    2016-10-01

    Full Text Available Maternal exposure to infectious agents is a predisposing factor for schizophrenia with associated cognitive deficits in offspring. A high incidence of smoking in these individuals in adulthood might be, at least in part, due to the cognitive-enhancing effects of nicotine. Here, we have used prenatal exposure to maternal lipopolysaccharide (LPS, bacterial endotoxin at different time points as a model for cognitive deficits in schizophrenia to determine whether nicotine reverses any associated impairments. Pregnant rats were treated subcutaneously with LPS (0.5 mg/kg at one of three neurodevelopmental time periods [gestation days (GD 10-11, 15-16, 18-19]. Cognitive assessment in male offspring commenced in early adulthood [postnatal day (PND 60] and included: prepulse inhibition (PPI, latent inhibition (LI and delayed non-matching to sample (DNMTS. Following PND 100, daily nicotine injections (0.6 mg/kg, subcutaneously were administered, and animals were re-tested in the same tasks (PND 110. Only maternal LPS exposure early during fetal neurodevelopment (GD 10-11 resulted in deficits in all tests compared to animals that had been prenatally exposed to saline at the same gestational time point. Repeated nicotine treatment led to global (PPI and selective (LI improvements in performance. Early but not later prenatal LPS exposure induced consistent deficits in cognitive tests with relevance for schizophrenia. Nicotine reversed the LPS-induced deficits in selective attention (LI and induced a global enhancement of sensorimotor gating (PPI.

  10. Ethanol exposure affects cell movement during gastrulation and induces split axes in zebrafish embryos.

    Science.gov (United States)

    Zhang, Ying; Shao, Ming; Wang, Lifeng; Liu, Zhongzhen; Gao, Ming; Liu, Chao; Zhang, Hongwei

    2010-06-01

    To explore the toxic effects of ethanol on axis formation during embryogenesis, zebrafish embryos at different developmental stages were treated with 3% ethanol for 3h. The effects of ethanol exposure appeared to be stage-dependent. The dome stage embryo was most sensible to form posterior split axes upon ethanol exposure. Morphological and histological observations and whole-mount in situ hybridization results showed that ethanol exposure at this stage caused a general gastrulation delay, and induced double notochords, double neural tubes and two sets of somites in the posterior trunk. Mechanistically, no ectopic organizer was found by examining the expression patterns of dorsoventral markers including goosecoid, chordin and eve1 at the onset of gastrulation. However, radial intercalation, epiboly and convergence extension were inhibited by ethanol exposure as revealed by cell labeling, phenotypic observation and the expression patterns of axial or paraxial markers. Further investigation showed that the cell aggregation might be affected by ethanol exposure, as indicated by the much more scattered expression pattern of chordin, eve1 and wnt11 at the early gastrula stage, and the discontinuous gsc positive cells during migration. These results imply that ethanol might affect cell movement before and during gastrulation and as a consequence, induces a split axes phenotype. Copyright 2010 ISDN. Published by Elsevier Ltd. All rights reserved.

  11. Perfluorooctanoic acid exposure for 28 days affects glucose homeostasis and induces insulin hypersensitivity in mice

    Science.gov (United States)

    Yan, Shengmin; Zhang, Hongxia; Zheng, Fei; Sheng, Nan; Guo, Xuejiang; Dai, Jiayin

    2015-06-01

    Perfluoroalkyl acids (PFAAs) are widely used in many applications due to their unique physical and chemical characteristics. Because of the increasing prevalence of metabolic syndromes, including obesity, dyslipidemia and insulin resistance, concern has arisen about the roles of environmental pollutants in such diseases. Earlier epidemiologic studies showed a potential association between perfluorooctanoic acid (PFOA) and glucose metabolism, but how PFOA influences glucose homeostasis is still unknown. Here, we report on the modulation of the phosphatidylinositol 3-kinase-serine/threonine protein kinase (PI3K-AKT) signaling pathway in the livers of mice after 28 d of exposure to PFOA. Compared with normal mice, PFOA exposure significantly decreased the expression of the phosphatase and tensin homologue (PTEN) protein and affected the PI3K-AKT signaling pathway in the liver. Tolerance tests further indicated that PFOA exposure induced higher insulin sensitivity and glucose tolerance in mice. Biochemical analysis revealed that PFOA exposure reduced hepatic glycogen synthesis, which might be attributed to gluconeogenesis inhibition. The levels of several circulating proteins were altered after PFOA exposure, including proteins potentially related to diabetes and liver disease. Our results suggest that PFOA affected glucose metabolism and induced insulin hypersensitivity in mice.

  12. Exposure to mercuric chloride induces developmental damage, oxidative stress and immunotoxicity in zebrafish embryos-larvae.

    Science.gov (United States)

    Zhang, Qun-Fang; Li, Ying-Wen; Liu, Zhi-Hao; Chen, Qi-Liang

    2016-12-01

    Mercury (Hg) is a widespread environmental pollutant that can produce severe negative effects on fish even at very low concentrations. However, the mechanisms underlying inorganic Hg-induced oxidative stress and immunotoxicity in the early development stage of fish still need to be clarified. In the present study, zebrafish (Danio rerio) embryos were exposed to different concentrations of Hg 2+ (0, 1, 4 and 16μg/L; added as mercuric chloride, HgCl 2 ) from 2h post-fertilization (hpf) to 168hpf. Developmental parameters and total Hg accumulation were monitored during the exposure period, and antioxidant status and the mRNA expression of genes related to the innate immune system were examined at 168hpf. The results showed that increasing Hg 2+ concentration and time significantly increased total Hg accumulation in zebrafish embryos-larvae. Exposure to 16μg/L Hg 2+ caused developmental damage, including increased mortality and malformation, decreased body length, and delayed hatching period. Meanwhile, HgCl 2 exposure (especially in the 16μg/L Hg 2+ group) induced oxidative stress affecting antioxidant enzyme (CAT, GST and GPX) activities, endogenous GSH and MDA contents, as well as the mRNA levels of genes (cat1, sod1, gstr, gpx1a, nrf2, keap1, hsp70 and mt) encoding antioxidant proteins. Moreover, the transcription levels of several representative genes (il-1β, il-8, il-10, tnfα2, lyz and c3) involved in innate immunity were up-regulated by HgCl 2 exposure, suggesting that inorganic Hg had the potential to induce immunotoxicity. Taken together, the present study provides evidence that waterborne HgCl 2 exposure can induce developmental impairment, oxidative stress and immunotoxicity in the early development stage of fish, which brings insights into the toxicity mechanisms of inorganic Hg in fish. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Biomarkers of exposure, effect, and susceptibility of arsenic-induced health hazards in Taiwan

    International Nuclear Information System (INIS)

    Chen, C.-J.; Hsu, L.-I; Wang, C.-H.

    2005-01-01

    Long-term exposure to inorganic arsenic from drinking water has been documented to induce cancers and vascular diseases in a dose-response relationship. A series of molecular environmental epidemiological studies have been carried out to elucidate biomarkers of exposure, effect, and susceptibility for arsenic-related health hazards in Taiwan. Arsenic levels in urine, hair, and nail are biomarkers for short-term (<1 year) internal dose, skin hyperpigmentation and palmoplantar hyperkeratosis are for long-term (many years) internal dose, and percentage of monomethylarsonic acid in total metabolites of inorganic arsenic in urine may be considered as an exposure marker for biologically effective dose. The biomarkers of early biological effects of ingested inorganic arsenic included blood levels of reactive oxidants and anti-oxidant capacity, genetic expression of inflammatory molecules, as well as cytogenetic changes including sister chromatid exchange, micronuclei, and chromosome aberrations of peripheral lymphocytes. Both mutation type and hot spots of p53 gene were significantly different in arsenic-induced and non-arsenic-induced TCCs. The frequency of chromosomal imbalances analyzed by comparative genomic hybridization and the frequency of loss of heterozygosity were significantly higher in arsenic-induced TCC than non-arsenic-induced TCC at specific sites. Biomarkers of susceptibility to arsenic-induced health hazards included genetic polymorphisms of enzymes involved in xenobiotic metabolism, DNA repair, and oxidative stress, as well as serum level of carotenoids. Gene-gene and gene-environment interactions are involved in arsenic-induced health hazards through toxicological mechanisms including genomic instability and oxidative stress

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

    Directory of Open Access Journals (Sweden)

    Amie L. Holmes

    2013-11-01

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

  15. Assessment of the mode of action for hexavalent chromium-induced lung cancer following inhalation exposures

    International Nuclear Information System (INIS)

    Proctor, Deborah M.; Suh, Mina; Campleman, Sharan L.; Thompson, Chad M.

    2014-01-01

    Highlights: • No published or well recognized MOA for Cr(VI)-induced lung tumors exists. • MOA analysis for Cr(VI)-induced lung cancer was conducted to inform risk assessment. • Cr(VI) epidemiologic, toxicokinetic, toxicological, mechanistic data were evaluated. • Weight of evidence does not support a mutagenic MOA for Cr(VI)-induced lung cancer. • Non-linear approaches should be considered for evaluating Cr(VI) lung cancer risk. - Abstract: Inhalation of hexavalent chromium [Cr(VI)] is associated with increased lung cancer risk among workers in several industries, most notably chromate production workers exposed to high concentrations of Cr(VI) (≥100 μg/m 3 ), for which clear exposure–response relationships and respiratory irritation and tissue damage have been reported. Data from this industry are used to assess lung cancer risk associated with environmental and current occupational exposures, occurring at concentrations that are significantly lower. There is considerable uncertainty in the low dose extrapolation of historical occupational epidemiology data to assess risk at current exposures because no published or well recognized mode of action (MOA) for Cr(VI)-induced lung tumors exists. We conducted a MOA analysis for Cr(VI)-induced lung cancer evaluating toxicokinetic and toxicological data in humans and rodents and mechanistic data to assess plausibility, dose–response, and temporal concordance for potential MOAs. Toxicokinetic data support that extracellular reduction of Cr(VI), which limits intracellular absorption of Cr(VI) and Cr(VI)-induced toxicity, can be overwhelmed at high exposure levels. In vivo genotoxicity and mutagenicity data are mostly negative and do not support a mutagenic MOA. Further, both chronic bioassays and the epidemiologic literature support that lung cancer occurs at exposures that cause tissue damage. Based on this MOA analysis, the overall weight of evidence supports a MOA involving deposition and accumulation

  16. Chemically enhanced sunlight for killing bacteria

    International Nuclear Information System (INIS)

    Block, S.S.; Goswami, D.Y.

    1995-01-01

    Solar ultraviolet (UV) photocatalyzed oxidation of chemicals with titanium dioxide (TiO 2 ) has received considerable attention. Much less recognized, however, is the ability of the same system to destroy bacteria. This study examined this phenomenon and the conditions that affect it. Bacteria in aqueous solution were given solar exposure with titanium dioxide and their survival with time was determined. Lamps with a predominantly solar ultraviolet spectrum were also used in the experiments. Without exposure to UV light, TiO 2 had no deleterious effect on the bacteria. However, several common bacteria on solar exposure in the presence of TiO 2 were killed in just a few minutes, whereas without TiO 2 it took over an hour to destroy them. A concentration of 0.01% TiO 2 was most effective in killing bacteria and 10-fold concentrations lower or higher were successively less effective. Inorganic and organic compounds in solution, even in small amounts, interfered with the efficiency of killing. Alkaline solution also reduced the bactericidal activity. Circulation and agitation provided by stirring to keep the TiO 2 particles suspended reduced the time necessary to kill the bacteria. Time-intensity curves for killing bacteria were the same general shape with or without TiO 2 , indicating that TiO 2 served merely as a catalyst to increase the rate of the reaction but that the mechanism of action was not changed. The shape of the curves show that the organisms are sensitized with a minimum intensity of radiation and that an increase doesn't greatly increase the rate of kill. Below this critical intensity, however, the time required for killing markedly increases as the intensity is decreased

  17. Digital music exposure reliably induces temporary threshold shift (TTS) in normal hearing human subjects

    Science.gov (United States)

    Le Prell, C. G.; Dell, S.; Hensley, B.; Hall, J. W.; Campbell, K. C. M.; Antonelli, P. J.; Green, G. E.; Miller, J. M.; Guire, K.

    2012-01-01

    Objectives One of the challenges for evaluating new otoprotective agents for potential benefit in human populations is availability of an established clinical paradigm with real world relevance. These studies were explicitly designed to develop a real-world digital music exposure that reliably induces temporary threshold shift (TTS) in normal hearing human subjects. Design Thirty-three subjects participated in studies that measured effects of digital music player use on hearing. Subjects selected either rock or pop music, which was then presented at 93–95 (n=10), 98–100 (n=11), or 100–102 (n=12) dBA in-ear exposure level for a period of four hours. Audiograms and distortion product otoacoustic emissions (DPOAEs) were measured prior to and after music exposure. Post-music tests were initiated 15 min, 1 hr 15 min, 2 hr 15 min, and 3 hr 15 min after the exposure ended. Additional tests were conducted the following day and one week later. Results Changes in thresholds after the lowest level exposure were difficult to distinguish from test-retest variability; however, TTS was reliably detected after higher levels of sound exposure. Changes in audiometric thresholds had a “notch” configuration, with the largest changes observed at 4 kHz (mean=6.3±3.9dB; range=0–13 dB). Recovery was largely complete within the first 4 hours post-exposure, and all subjects showed complete recovery of both thresholds and DPOAE measures when tested 1-week post-exposure. Conclusions These data provide insight into the variability of TTS induced by music player use in a healthy, normal-hearing, young adult population, with music playlist, level, and duration carefully controlled. These data confirm the likelihood of temporary changes in auditory function following digital music player use. Such data are essential for the development of a human clinical trial protocol that provides a highly powered design for evaluating novel therapeutics in human clinical trials. Care must be

  18. Genome-Wide Transcriptional Profiles of the Berry Skin of Two Red Grape Cultivars (Vitis vinifera) in Which Anthocyanin Synthesis Is Sunlight-Dependent or -Independent

    Science.gov (United States)

    Guan, Le; Xin, Hai-Ping; Li, Ji-Hu; Li, Shao-Hua

    2014-01-01

    Global gene expression was analyzed in the berry skin of two red grape cultivars, which can (‘Jingyan’) or cannot (‘Jingxiu’) synthesize anthocyanins after sunlight exclusion from fruit set until maturity. Gene transcripts responding to sunlight exclusion in ‘Jingyan’ were less complex than in ‘Jingxiu’; 528 genes were induced and 383 repressed in the former, whereas 2655 genes were induced and 205 suppressed in ‘Jingxiu’. They were regulated either in the same or opposing manner in the two cultivars, or in only one cultivar. In addition to VvUFGT and VvMYBA1, some candidate genes (e.g. AOMT, GST, and ANP) were identified which are probably involved in the differential responses of ‘Jingxiu’ and ‘Jingyan’ to sunlight exclusion. In addition, 26 MYB, 14 bHLH and 23 WD40 genes responded differently to sunlight exclusion in the two cultivars. Interestingly, all of the 189 genes classified as being relevant to ubiquitin-dependent protein degradation were down-regulated by sunlight exclusion in ‘Jingxiu’, but the majority (162) remained unchanged in ‘Jingyan’ berry skin. It would be of interest to determine the precise role of the ubiquitin pathway following sunlight exclusion, particularly the role of COP9 signalosome, cullins, RING-Box 1, and COP1-interacting proteins. Only a few genes in the light signal system were found to be regulated by sunlight exclusion in either or both cultivars. This study provides a valuable overview of the transcriptome changes and gives insight into the genetic background that may be responsible for sunlight-dependent versus -independent anthocyanin biosynthesis in berry skin. PMID:25158067

  19. Exposure to radiofrequency radiation induces oxidative stress in duckweed Lemna minor L

    Energy Technology Data Exchange (ETDEWEB)

    Tkalec, Mirta [Department of Botany, Division of Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, HR-10000 Zagreb (Croatia)], E-mail: mtkalec@zg.biol.pmf.hr; Malaric, Kresimir [Faculty of Electrical Engineering and Computing, University of Zagreb, Unska 3, HR-10000 Zagreb (Croatia); Pevalek-Kozlina, Branka [Department of Botany, Division of Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, HR-10000 Zagreb (Croatia)

    2007-12-15

    23 V m{sup -1}. At both frequencies no differences in isoenzyme patterns of antioxidative enzymes or HSP70 level were found between control and exposed plants. Our results showed that non-thermal exposure to investigated radiofrequency fields induced oxidative stress in duckweed as well as unspecific stress responses, especially of antioxidative enzymes. However, the observed effects markedly depended on the field frequencies applied as well as on other exposure parameters (strength, modulation and exposure time). Enhanced lipid peroxidation and H{sub 2}O{sub 2} content accompanied by diminished antioxidative enzymes activity caused by exposure to investigated EMFs, especially at 900 MHz, indicate that oxidative stress could partly be due to changed activities of antioxidative enzymes.

  20. Study on the immunological and genetic effects induced by internal exposure to radionuclides

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Wang Liuyi; Luan Meiling

    1995-02-01

    The immune system is the important part of defense mechanism in organism. Studies have demonstrated the high radiosensitivity of the immunocytes to internal radionuclide exposure. It is evident that serious functional disturbances and morphological changes of immune organs are induced by internal contamination of radionuclides, including suppression of division and proliferation of immunocytes, induction of irreversible sequelae, leading to injurious effects on both central and peripheral immune organs. In order to study the consequences of the injuries of genetic material caused by internal contamination of radionuclides, researches have developed from the harmful effects on parental generation to those on the offspring. The present paper reports the study on the genetic injuries of somatic and germ cells induced by internal radionuclide exposure. Emphasis is placed on the molecular basis of radio-genetic effect and the relations of the molecular basis of DNA injury to gene mutation and chromosome aberration

  1. Prepubertal exposure to cow's milk reduces susceptibility to carcinogen-induced mammary tumorigenesis in rats

    DEFF Research Database (Denmark)

    Nielsen, Tina Skau; Khan, Galam; Davis, Jennifer

    2011-01-01

    Cow's milk contains high levels of estrogens, progesterone and insulin-like growth factor 1 (IGF-1), all of which are associated with breast cancer. We investigated whether prepubertal milk exposure affects mammary gland development and carcinogenesis in rats. Sprague-Dawley rats were given either...... whole milk or tap water to drink from postnatal day (PND) 14 to PND 35, and thereafter normal tap water. Mammary tumorigenesis was induced by administering 7,12-dimethylbenz[a]anthracene on PND 50. Milk exposure increased circulating E2 levels on PND 25 by 10-fold (p ... opening, which marks puberty onset, by 2.5 days (p milk before puberty exhibited reduced carcinogen-induced mammary carcinogenesis; that is, their tumor latency was longer (p

  2. Successful pacing using a batteryless sunlight-powered pacemaker.

    Science.gov (United States)

    Haeberlin, Andreas; Zurbuchen, Adrian; Schaerer, Jakob; Wagner, Joerg; Walpen, Sébastien; Huber, Christoph; Haeberlin, Heinrich; Fuhrer, Juerg; Vogel, Rolf

    2014-10-01

    Today's cardiac pacemakers are powered by batteries with limited energy capacity. As the battery's lifetime ends, the pacemaker needs to be replaced. This surgical re-intervention is costly and bears the risk of complications. Thus, a pacemaker without primary batteries is desirable. The goal of this study was to test whether transcutaneous solar light could power a pacemaker. We used a three-step approach to investigate the feasibility of sunlight-powered cardiac pacing. First, the harvestable power was estimated. Theoretically, a subcutaneously implanted 1 cm(2) solar module may harvest ∼2500 µW from sunlight (3 mm implantation depth). Secondly, ex vivo measurements were performed with solar cells placed under pig skin flaps exposed to a solar simulator and real sunlight. Ex vivo measurements under real sunlight resulted in a median output power of 4941 µW/cm(2) [interquartile range (IQR) 3767-5598 µW/cm(2), median skin flap thickness 3.0 mm (IQR 2.7-3.3 mm)]. The output power strongly depended on implantation depth (ρSpearman = -0.86, P pacemaker powered by a 3.24 cm(2) solar module was implanted in vivo in a pig to measure output power and to pace. In vivo measurements showed a median output power of >3500 µW/cm(2) (skin flap thickness 2.8-3.84 mm). Successful batteryless VVI pacing using a subcutaneously implanted solar module was performed. Based on our results, we estimate that a few minutes of direct sunlight (irradiating an implanted solar module) allow powering a pacemaker for 24 h using a suitable energy storage. Thus, powering a pacemaker by sunlight is feasible and may be an alternative energy supply for tomorrow's pacemakers. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  3. Fetal cyclophosphamide exposure induces testicular cancer and reduced spermatogenesis and ovarian follicle numbers in mice.

    Science.gov (United States)

    Comish, Paul B; Drumond, Ana Luiza; Kinnell, Hazel L; Anderson, Richard A; Matin, Angabin; Meistrich, Marvin L; Shetty, Gunapala

    2014-01-01

    Exposure to radiation during fetal development induces testicular germ cell tumors (TGCT) and reduces spermatogenesis in mice. However, whether DNA damaging chemotherapeutic agents elicit these effects in mice remains unclear. Among such agents, cyclophosphamide (CP) is currently used to treat breast cancer in pregnant women, and the effects of fetal exposure to this drug manifested in the offspring must be better understood to offer such patients suitable counseling. The present study was designed to determine whether fetal exposure to CP induces testicular cancer and/or gonadal toxicity in 129 and in 129.MOLF congenic (L1) mice. Exposure to CP on embryonic days 10.5 and 11.5 dramatically increased TGCT incidence to 28% in offspring of 129 mice (control value, 2%) and to 80% in the male offspring of L1 (control value 33%). These increases are similar to those observed in both lines of mice by radiation. In utero exposure to CP also significantly reduced testis weights at 4 weeks of age to ∼ 70% of control and induced atrophic seminiferous tubules in ∼ 30% of the testes. When the in utero CP-exposed 129 mice reached adulthood, there were significant reductions in testicular and epididymal sperm counts to 62% and 70%, respectively, of controls. In female offspring, CP caused the loss of 77% of primordial follicles and increased follicle growth activation. The results indicate that i) DNA damage is a common mechanism leading to induction of testicular cancer, ii) increased induction of testis cancer by external agents is proportional to the spontaneous incidence due to inherent genetic susceptibility, and iii) children exposed to radiation or DNA damaging chemotherapeutic agents in utero may have increased risks of developing testis cancer and having reduced spermatogenic potential or diminished reproductive lifespan.

  4. Fetal cyclophosphamide exposure induces testicular cancer and reduced spermatogenesis and ovarian follicle numbers in mice.

    Directory of Open Access Journals (Sweden)

    Paul B Comish

    Full Text Available Exposure to radiation during fetal development induces testicular germ cell tumors (TGCT and reduces spermatogenesis in mice. However, whether DNA damaging chemotherapeutic agents elicit these effects in mice remains unclear. Among such agents, cyclophosphamide (CP is currently used to treat breast cancer in pregnant women, and the effects of fetal exposure to this drug manifested in the offspring must be better understood to offer such patients suitable counseling. The present study was designed to determine whether fetal exposure to CP induces testicular cancer and/or gonadal toxicity in 129 and in 129.MOLF congenic (L1 mice. Exposure to CP on embryonic days 10.5 and 11.5 dramatically increased TGCT incidence to 28% in offspring of 129 mice (control value, 2% and to 80% in the male offspring of L1 (control value 33%. These increases are similar to those observed in both lines of mice by radiation. In utero exposure to CP also significantly reduced testis weights at 4 weeks of age to ∼ 70% of control and induced atrophic seminiferous tubules in ∼ 30% of the testes. When the in utero CP-exposed 129 mice reached adulthood, there were significant reductions in testicular and epididymal sperm counts to 62% and 70%, respectively, of controls. In female offspring, CP caused the loss of 77% of primordial follicles and increased follicle growth activation. The results indicate that i DNA damage is a common mechanism leading to induction of testicular cancer, ii increased induction of testis cancer by external agents is proportional to the spontaneous incidence due to inherent genetic susceptibility, and iii children exposed to radiation or DNA damaging chemotherapeutic agents in utero may have increased risks of developing testis cancer and having reduced spermatogenic potential or diminished reproductive lifespan.

  5. Perinatal DDT Exposure Induces Hypertension and Cardiac Hypertrophy in Adult Mice.

    Science.gov (United States)

    La Merrill, Michele A; Sethi, Sunjay; Benard, Ludovic; Moshier, Erin; Haraldsson, Borje; Buettner, Christoph

    2016-11-01

    Dichlorodiphenyltrichloroethane (DDT) was used extensively to control malaria, typhus, body lice, and bubonic plague worldwide, until countries began restricting its use in the 1970s. However, the use of DDT to control vector-borne diseases continues in developing countries. Prenatal DDT exposure is associated with elevated blood pressure in humans. We hypothesized that perinatal DDT exposure causes hypertension in adult mice. DDT was administered to C57BL/6J dams from gestational day 11.5 to postnatal day 5. Blood pressure (BP) and myocardial wall thickness were measured in male and female adult offspring. Adult mice were treated with an angiotensin converting enzyme (ACE) inhibitor, captopril, to evaluate sensitivity to amelioration of DDT-associated hypertension by ACE inhibition. We further assessed the influence of DDT exposure on the expression of mRNAs that regulate BP through renal ion transport. Adult mice perinatally exposed to DDT exhibited chronically increased systolic BP, increased myocardial wall thickness, and elevated expression of mRNAs of several renal ion transporters. Captopril completely reversed hypertension in mice perinatally exposed to DDT. These data demonstrate that perinatal exposure to DDT causes hypertension and cardiac hypertrophy in adult offspring. A key mechanism underpinning this hypertension is an overactivated renin angiotensin system because ACE inhibition reverses the hypertension induced by perinatal DDT exposure. Citation: La Merrill M, Sethi S, Benard L, Moshier E, Haraldsson B, Buettner C. 2016. Perinatal DDT exposure induces hypertension and cardiac hypertrophy in adult mice. Environ Health Perspect 124:1722-1727; http://dx.doi.org/10.1289/EHP164.

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

    Science.gov (United States)

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

    2014-07-01

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

  7. Photodegradation of pharmaceuticals in the aquatic environment by sunlight and UV-A, -B and -C irradiation.

    Science.gov (United States)

    Kawabata, Kohei; Sugihara, Kazumi; Sanoh, Seigo; Kitamura, Shigeyuki; Ohta, Shigeru

    2013-01-01

    In order to investigate the effect of sunlight on the persistence and ecotoxicity of pharmaceuticals contaminating the aquatic environment, we exposed nine pharmaceuticals (acetaminophen (AA), amiodarone (AM), dapsone (DP), dexamethasone (DX), indomethacin (IM), naproxen (NP), phenytoin (PH), raloxifene (RL), and sulindac (SL)) in aqueous media to sunlight and to ultraviolet (UV) irradiation at 254, 302 or 365 nm (UV-C, UV-B or UV-A, respectively). Degradation of the pharmaceuticals was monitored by means of high-performance liquid chromatography (HPLC). Sunlight completely degraded AM, DP and DX within 6 hr, and partly degraded the other pharmaceuticals, except AA and PH, which were not degraded. Similar results were obtained with UV-B, while UV-A was less effective (both UV-A and -B are components of sunlight). All the pharmaceuticals were photodegraded by UV-C, which is used for sterilization in sewage treatment plants. Thus, the photodegradation rates of pharmaceuticals are dependent on both chemical structure and the wavelength of UV exposure. Toxicity assay using the luminescent bacteria test (ISO11348) indicated that UV irradiation reduced the toxicity of some pharmaceuticals to aquatic organisms by decreasing their amount (photodegradation) and increased the toxicity of others by generating toxic photoproduct(s). These results indicate the importance of investigating not only parent compounds, but also photoproducts in the risk assessment of pharmaceuticals in aquatic environments.

  8. Low-dose cadmium exposure exacerbates polyhexamethylene guanidine-induced lung fibrosis in mice.

    Science.gov (United States)

    Kim, Min-Seok; Kim, Sung-Hwan; Jeon, Doin; Kim, Hyeon-Young; Han, Jin-Young; Kim, Bumseok; Lee, Kyuhong

    2018-01-01

    Cadmium (Cd) is a toxic metal present in tobacco smoke, air, food, and water. Inhalation is an important route of Cd exposure, and lungs are one of the main target organs for metal-induced toxicity. Cd inhalation is associated with an increased risk of pulmonary diseases. The present study aimed to assess the effects of repeated exposure to low-dose Cd in a mouse model of polyhexamethylene guanidine (PHMG)-induced lung fibrosis. Mice were grouped into the following groups: vehicle control (VC), PHMG, cadmium chloride (CdCl 2 ), and PHMG + CdCl 2 . Animals in the PHMG group exhibited increased numbers of total cells and inflammatory cells in the bronchoalveolar lavage fluid (BALF) accompanied by inflammation and fibrosis in lung tissues. These parameters were exacerbated in mice in the PHMG + CdCl 2 group. In contrast, mice in the CdCl 2 group alone displayed only minimal inflammation in pulmonary tissue. Expression of inflammatory cytokines and fibrogenic mediators was significantly elevated in lungs of mice in the PHMG group compared with that VC. Further, expression of these cytokines and mediators was enhanced in pulmonary tissue in mice administered PHMG + CdCl 2 . Data demonstrate that repeated exposure to low-dose Cd may enhance the development of PHMG-induced pulmonary fibrosis.

  9. Maternal Sevoflurane Exposure Causes Abnormal Development of Fetal Prefrontal Cortex and Induces Cognitive Dysfunction in Offspring

    Directory of Open Access Journals (Sweden)

    Ruixue Song

    2017-01-01

    Full Text Available Maternal sevoflurane exposure during pregnancy is associated with increased risk for behavioral deficits in offspring. Several studies indicated that neurogenesis abnormality may be responsible for the sevoflurane-induced neurotoxicity, but the concrete impact of sevoflurane on fetal brain development remains poorly understood. We aimed to investigate whether maternal sevoflurane exposure caused learning and memory impairment in offspring through inducing abnormal development of the fetal prefrontal cortex (PFC. Pregnant mice at gestational day 15.5 received 2.5% sevoflurane for 6 h. Learning function of the offspring was evaluated with the Morris water maze test at postnatal day 30. Brain tissues of fetal mice were subjected to immunofluorescence staining to assess differentiation, proliferation, and cell cycle dynamics of the fetal PFC. We found that maternal sevoflurane anesthesia impaired learning ability in offspring through inhibiting deep-layer immature neuron output and neuronal progenitor replication. With the assessment of cell cycle dynamics, we established that these effects were mediated through cell cycle arrest in neural progenitors. Our research has provided insights into the cell cycle-related mechanisms by which maternal sevoflurane exposure can induce neurodevelopmental abnormalities and learning dysfunction and appeals people to consider the neurotoxicity of anesthetics when considering the benefits and risks of nonobstetric surgical procedures.

  10. Exposure to nickel oxide nanoparticles induces pulmonary inflammation through NLRP3 inflammasome activation in rats.

    Science.gov (United States)

    Cao, Zhengwang; Fang, Yiliang; Lu, Yonghui; Qian, Fenghua; Ma, Qinglong; He, Mingdi; Pi, Huifeng; Yu, Zhengping; Zhou, Zhou

    2016-01-01

    With recent advances in the manufacture and application of nickel oxide nanoparticles (NiONPs), concerns about their adverse effects on the respiratory system are increasing. However, the underlying cellular and molecular mechanisms of NiONP-induced pulmonary toxicity remain unclear. In this study, we focused on the impacts of NiONPs on pulmonary inflammation and investigated whether the NLRP3 inflammasome is involved in NiONP-induced pulmonary inflammation and injury. NiONP suspensions were administered by single intratracheal instillation to rats, and inflammatory responses were evaluated at 3 days, 7 days, or 28 days after treatment. NiONP exposure resulted in sustained pulmonary inflammation accompanied by inflammatory cell infiltration, alveolar proteinosis, and cytokine secretion. Expression of Nlrp3 was markedly upregulated by the NiONPs, which was accompanied by overexpression of the active form of caspase-1 (p20) and interleukin (IL)-1β secretion in vivo. NiONP-induced IL-1β secretion was partially prevented by co-treatment with a caspase-1 inhibitor in macrophages. Moreover, siRNA-mediated Nlrp3 knockdown completely attenuated NiONP-induced cytokine release and caspase-1 activity in macrophages in vitro. In addition, NiONP-induced NLRP3 inflammasome activation requires particle uptake and reactive oxygen species production. Collectively, our findings suggest that the NLRP3 inflammasome participates in NiONP-induced pulmonary inflammation and offer new strategies to combat the pulmonary toxicity induced by NiONPs.

  11. Canadian individual risks of radon-induced lung cancer for different exposure profiles.

    Science.gov (United States)

    Chen, Jing

    2005-01-01

    Indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. There is an increasing need among radiation practitioners to have numerical values of lung cancer risks for men and women, ever-smokers and never-smokers exposed to radon in homes. This study evaluates individual risks for the Canadian population exposed to radon in homes at different radon concentrations and for different periods of their lives. Based on the risk model developed recently by U.S. Environmental Protection Agency (EPA), individual risks of radon-induced lung cancers are calculated with Canadian age-specific rates for overall and lung cancer mortalities (1996-2000) as well as the Canadian smoking prevalence data in 2002. Convenient tables of lifetime relative risks are constructed for lifetime exposures and short exposures between any two age intervals from 0 to 110, and for various radon concentrations found in homes from 50 to 1000 Bq/m3. The risk of developing lung cancer from residential radon exposure increases with radon concentration and exposure duration. For short exposure periods, such as 10 or 20 years, risks are higher in middle age groups (30-50) compared especially to the later years. Individuals could lower their risks significantly by reducing radon levels earlier in life. The tables could help radiation protection practitioners to better communicate indoor radon risk to members of the public.

  12. Dissolved organic carbon biodegradability from thawing permafrost stimulated by sunlight rather than inorganic nitrogen

    Science.gov (United States)

    Liu, F.; Chen, L.; Zhang, B.; Wang, G.; Qin, S.; Yang, Y.

    2017-12-01

    Permafrost thaw could result in a large portion of frozen carbon being laterally transferred to aquatic ecosystems as dissolved organic carbon (DOC). During this delivery process, the size of biodegradable DOC (BDOC) determines the proportion of DOC mineralized by microorganisms and associated carbon loss to the atmosphere, which may further trigger positive carbon-climate feedback. Thermokarst is an abrupt permafrost thaw process that can enhance DOC export and also impact DOC processing through increased inorganic nitrogen (N) and sunlight exposure. However, it remains unclear how thermokarst-impacted BDOC responds to inorganic N addition and ultraviolet (UV) light irradiation. Here we explored the responses of DOC concentration, composition and its biodegradability to inorganic N and UV light in a typical thermokarst on the Tibetan Plateau, by combining field observation and laboratory incubation with spectra analyses (UV-visible absorption and three-dimensional fluorescence spectra) and parallel factor analyses. Our results showed that BDOC in thermokarst feature outflows was significantly higher than in reference water. Furthermore, inorganic N addition had no influence on thermokarst-impacted BDOC, whereas exposure to UV light significantly increased BDOC by as much as 2.3 times higher than the dark-control. Moreover, N addition and UV irradiation did not generate additive effects on BDOC. These results imply that sunlight rather than inorganic N can increase thermokarst-derived BDOC, potentially strengthening the positive permafrost carbon-climate feedback.

  13. Arsenic induced apoptosis in rat liver following repeated 60 days exposure

    International Nuclear Information System (INIS)

    Bashir, Somia; Sharma, Yukti; Irshad, M.; Nag, T.C.; Tiwari, Monica; Kabra, M.; Dogra, T.D.

    2006-01-01

    Background: Accumulation of the wide spread environmental toxin arsenic in liver results in hepatotoxcity. Exposure to arsenite and other arsenicals has been previously shown to induce apoptosis in certain tumor cell lines at low (1-3 μM) concentration. Aim: The present study was focused to elucidate the role of free radicals in arsenic toxicity and to investigate the nature of in vivo sodium arsenite induced cell death in liver. Methods: Male wistar rats were exposed to arsenite at three different doses of 0.05, 2.5 and 5 mg/l for 60 days. Oxidative stress in liver was measured by estimating pro-oxidant and antioxidant activity in liver. Histopathological examination of liver was carried out by light and transmission electron microscopy. Analysis of DNA fragmentation by gel electrophoresis was used to identify apoptosis after the exposure. Terminal deoxy-nucleotidyl transferase mediated dUTP Nick end-labeling (TUNEL) assay was used to qualify and quantify apoptosis. Results: A significant increase in cytochrome-P450 and lipid peroxidation accompanied with a significant alteration in the activity of many of the antioxidants was observed, all suggestive of arsenic induced oxidative stress. Histopathological examination under light and transmission electron microscope suggested a combination of ongoing necrosis and apoptosis. DNA-TUNEL showed an increase in apoptotic cells in liver. Agarose gel electrophoresis of DNA of hepatocytes resulted in a characteristic ladder pattern. Conclusion: Chronic arsenic administration induces a specific pattern of apoptosis called post-mitotic apoptosis

  14. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats.

    Science.gov (United States)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen; Zhang, Jie; Shen, Heqing

    2017-10-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33 proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb cardiac contraction and relaxation, impair heart morphogenesis and development, and induce thrombosis in rats, which is mediated by the Akt/p38 MAPK signaling pathway. Overall, these findings will augment our knowledge of the involved mechanisms and develop useful biomarkers for cardiotoxicity induced by environmental arsenic exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Subchronic JP-8 jet fuel exposure enhances vulnerability to noise-induced hearing loss in rats.

    Science.gov (United States)

    Fechter, L D; Fisher, J W; Chapman, G D; Mokashi, V P; Ortiz, P A; Reboulet, J E; Stubbs, J E; Lear, A M; McInturf, S M; Prues, S L; Gearhart, C A; Fulton, S; Mattie, D R

    2012-01-01

    Both laboratory and epidemiological studies published over the past two decades have identified the risk of excess hearing loss when specific chemical contaminants are present along with noise. The objective of this study was to evaluate the potency of JP-8 jet fuel to enhance noise-induced hearing loss (NIHL) using inhalation exposure to fuel and simultaneous exposure to either continuous or intermittent noise exposure over a 4-wk exposure period using both male and female Fischer 344 rats. In the initial study, male (n = 5) and female (n = 5) rats received inhalation exposure to JP-8 fuel for 6 h/d, 5 d/wk for 4 wk at concentrations of 200, 750, or 1500 mg/m³. Parallel groups of rats also received nondamaging noise (constant octave band noise at 85 dB(lin)) in combination with the fuel, noise alone (75, 85, or 95 dB), or no exposure to fuel or noise. Significant concentration-related impairment of auditory function measured by distortion product otoacoustic emissions (DPOAE) and compound action potential (CAP) threshold was seen in rats exposed to combined JP-8 plus noise exposure when JP-8 levels of 1500 mg/m³ were presented with trends toward impairment seen with 750 mg/m³ JP-8 + noise. JP-8 alone exerted no significant effect on auditory function. In addition, noise was able to disrupt the DPOAE and increase auditory thresholds only when noise exposure was at 95 dB. In a subsequent study, male (n = 5 per group) and female (n = 5 per group) rats received 1000 mg/m³ JP-8 for 6 h/d, 5 d/wk for 4 wk with and without exposure to 102 dB octave band noise that was present for 15 min out of each hour (total noise duration 90 min). Comparisons were made to rats receiving only noise, and thosereceiving no experimental treatment. Significant impairment of auditory thresholds especially for high-frequency tones was identified in the male rats receiving combined treatment. This study provides a basis for estimating excessive hearing loss under

  16. Digital music exposure reliably induces temporary threshold shift in normal-hearing human subjects.

    Science.gov (United States)

    Le Prell, Colleen G; Dell, Shawna; Hensley, Brittany; Hall, James W; Campbell, Kathleen C M; Antonelli, Patrick J; Green, Glenn E; Miller, James M; Guire, Kenneth

    2012-01-01

    One of the challenges for evaluating new otoprotective agents for potential benefit in human populations is the availability of an established clinical paradigm with real-world relevance. These studies were explicitly designed to develop a real-world digital music exposure that reliably induces temporary threshold shift (TTS) in normal-hearing human subjects. Thirty-three subjects participated in studies that measured effects of digital music player use on hearing. Subjects selected either rock or pop music, which was then presented at 93 to 95 (n = 10), 98 to 100 (n = 11), or 100 to 102 (n = 12) dBA in-ear exposure level for a period of 4 hr. Audiograms and distortion product otoacoustic emissions (DPOAEs) were measured before and after music exposure. Postmusic tests were initiated 15 min, 1 hr 15 min, 2 hr 15 min, and 3 hr 15 min after the exposure ended. Additional tests were conducted the following day and 1 week later. Changes in thresholds after the lowest-level exposure were difficult to distinguish from test-retest variability; however, TTS was reliably detected after higher levels of sound exposure. Changes in audiometric thresholds had a "notch" configuration, with the largest changes observed at 4 kHz (mean = 6.3 ± 3.9 dB; range = 0-14 dB). Recovery was largely complete within the first 4 hr postexposure, and all subjects showed complete recovery of both thresholds and DPOAE measures when tested 1 week postexposure. These data provide insight into the variability of TTS induced by music-player use in a healthy, normal-hearing, young adult population, with music playlist, level, and duration carefully controlled. These data confirm the likelihood of temporary changes in auditory function after digital music-player use. Such data are essential for the development of a human clinical trial protocol that provides a highly powered design for evaluating novel therapeutics in human clinical trials. Care must be taken to fully inform potential subjects in

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  18. Perturbations in immune responses induced by concurrent subchronic exposure to arsenic and endosulfan

    International Nuclear Information System (INIS)

    Aggarwal, Manoj; Naraharisetti, Suresh Babu; Dandapat, S.; Degen, G.H.; Malik, J.K.

    2008-01-01

    The metalloid arsenic and the chlorinated insecticide endosulfan are common environmental contaminants. Humans, animals, and birds are exposed to these chemicals through water and food. Although health effects due to either arsenic or endosulfan exposure are documented, the toxicological impact of co-exposure to these environmental pollutants is unpredictable and unknown. The present study was undertaken to assess whether concurrent exposure to arsenic and endosulfan induces significant alterations in immunological functions. Day-old chicks were exposed to 3.7 ppm of arsenic via drinking water and to 30 ppm of endosulfan-mixed feed either individually or concurrently for up to 60 days. All the chicks were vaccinated with Ranikhet disease virus (F-strain; RD-F) on days 1 and 30. During the course of study and at term, parameters of cellular and humoral immunity were determined. None of the treatments altered the absolute body weight or body weight gain, except arsenic significantly reduced weight gain on day 60. Absolute, but not the relative, weights of spleen, thymus and bursa of Fabricius were significantly reduced in all the treatment groups. The metalloid and insecticide combination significantly depressed the ability of peripheral blood and splenic lymphocytes to proliferate in response to antigen RD-F and mitogen Con A. The delayed type hypersensitivity response to 2,4-dinitro-1-chlorobenzene or to PHA-P was also significantly decreased. Nitric oxide production by RD-F or lipopolysaccharide-stimulated peripheral blood and splenic mononuclear cells was significantly suppressed following concurrent exposure to arsenic and endosulfan. Furthermore, the combined exposure also decreased the antibody response to RD-F. The suppression of cellular and humoral immune responses was also evident following administration of individual compounds, and it was not exacerbated following concurrent exposure. To our knowledge, this is the first report describing the suppression

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-01

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

  20. Sunlight triggers cutaneous lupus through a CSF-1-dependent mechanism in MRL-Fas(lpr) mice.

    Science.gov (United States)

    Menke, Julia; Hsu, Mei-Yu; Byrne, Katelyn T; Lucas, Julie A; Rabacal, Whitney A; Croker, Byron P; Zong, Xiao-Hua; Stanley, E Richard; Kelley, Vicki R

    2008-11-15

    Sunlight (UVB) triggers cutaneous lupus erythematosus (CLE) and systemic lupus through an unknown mechanism. We tested the hypothesis that UVB triggers CLE through a CSF-1-dependent, macrophage (Mø)-mediated mechanism in MRL-Fas(lpr) mice. By constructing mutant MRL-Fas(lpr) strains expressing varying levels of CSF-1 (high, intermediate, none), and use of an ex vivo gene transfer to deliver CSF-1 intradermally, we determined that CSF-1 induces CLE in lupus-susceptible MRL-Fas(lpr) mice, but not in lupus-resistant BALB/c mice. UVB incites an increase in Møs, apoptosis in the skin, and CLE in MRL-Fas(lpr), but not in CSF-1-deficient MRL-Fas(lpr) mice. Furthermore, UVB did not induce CLE in BALB/c mice. Probing further, UVB stimulates CSF-1 expression by keratinocytes leading to recruitment and activation of Møs that, in turn, release mediators, which induce apoptosis in keratinocytes. Thus, sunlight triggers a CSF-1-dependent, Mø-mediated destructive inflammation in the skin leading to CLE in lupus-susceptible MRL-Fas(lpr) but not lupus-resistant BALB/c mice. Taken together, CSF-1 is envisioned as the match and lupus susceptibility as the tinder leading to CLE.

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

    Directory of Open Access Journals (Sweden)

    Laura R. Hoyt

    2017-08-01

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

  2. Sunlight-enhanced catalytic degradation over Ag–CuO ...

    Indian Academy of Sciences (India)

    Herein, we report sunlight-activated photo-catalysis response of direct current radio frequency (DC/RF)-sputtered Ag–CuO nanoparticles thin films.We have adopted this approach for facile removal and easy recovery of thin filmsafter use. Ag was incorporated at 2.5 and 5.4 wt% with reference to pure CuO. Structural ...

  3. Effect of sunlight, transport and storage vessels on drinking water ...

    African Journals Online (AJOL)

    Effect of sunlight, transport and storage vessels on drinking water quality in rural Ghana. ... on drinking water quality in rural Ghana. K Obiri-Danso, E Amevor, LA Andoh, K Jones ... Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  4. Electricity from Sunlight: The Future of Photovoltaics. Worldwatch Paper 52.

    Science.gov (United States)

    Flavin, Christopher

    Solar photovoltaic cells have been called the ultimate energy technology, environmentally benign and without moving parts, solar cells directly convert sunlight into electricity. Photovoltaic energy conversion is fundamentally different from all other forms of electricity generation. Without turbines, generators or other mechanical equipment, it…

  5. Effect of sunlight shielding on leaf structure and amino acids ...

    African Journals Online (AJOL)

    Light sensitive albino tea cultivar 'Jinguang' (Camellia sinensis) which grows albinism leaf in yellow colour, results to high level of amino acids but low levels of photosynthetic pigments including chlorophylls, neoxanthin, violaxanthin, phytoxanthin and β-carotene when it is exposed to high sunlight illumination in the ...

  6. Turning Sunlight into Electricity-Inorganic Solar Cells and Beyond

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 12. Turning Sunlight into Electricity - Inorganic Solar Cells and Beyond. A K Shukla. Volume 16 Issue 12 December 2011 pp 1294-1302. Fulltext. Click here to view fulltext PDF. Permanent link:

  7. 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.

  8. Properties of light induced EPR signals in enamel and their possible interference with gamma-induced signals

    International Nuclear Information System (INIS)

    Sholom, S.V.; Chumak, V.V.; Haskell, E.H.; Hayes, R.B.; Kenner, G.H.

    1998-01-01

    Exposure of tooth enamel to natural and artificial UV light results in stable EPR signals with g-factors of 1.9985, 2.0018, 2.0045, 2.0052 and 2.0110. The first three signals correspond to the parallel and perpendicular components of the radiation induced or dosimetric signal and the native signal reported in dosimetry and dating studies. The latter two signals were found to be sensitive to both gamma-ray and sunlight exposure, however, their responses to light differed from that to radiation, giving rise to the possibility of using them as indicators of the dose-equivalent resulting from light exposure

  9. Histones induce phosphatidylserine exposure and a procoagulant phenotype in human red blood cells.

    Science.gov (United States)

    Semeraro, F; Ammollo, C T; Esmon, N L; Esmon, C T

    2014-10-01

    Extracellular histones exert part of their prothrombotic activity through the stimulation of blood cells. Besides platelets, histones can bind to red blood cells (RBCs), which are important contributors to thrombogenesis, but little is known about the functional consequences of this interaction. To evaluate the effect of histones on the procoagulant potential of human RBCs with particular regard to the expression of surface phosphatidylserine (PS). PS exposure on human RBCs treated with a natural mixture of histones or recombinant individual histones was evaluated with fluorescein isothiocyanate-annexin-V binding and measured with flow cytometry. Calcium influx in RBCs loaded with the calcium-sensitive fluorophore Fluo-4 AM was assessed with flow cytometry. The procoagulant potential of histone-treated RBCs was evaluated with a purified prothrombinase assay and a one-stage plasma recalcification clotting test. Natural histones induced PS exposure on RBCs in a dose-dependent manner, and neutralization or cleavage of histones by heparin or activated protein C, respectively, abolished PS externalization. H4 was mainly responsible for the stimulating activity of histones, whereas the other subtypes were almost ineffective. Similarly, natural histones and H4 induced influx of calcium into RBCs, whereas the other individual histones did not. Histone-induced exposure of PS on RBCs translated into increased prothrombinase complex-mediated prothrombin activation and accelerated fibrin formation in plasma. Histones induce RBCs to express a procoagulant phenotype through the externalization of PS. This finding provides new insights into the prothrombotic activity of extracellular histones. © 2014 International Society on Thrombosis and Haemostasis.

  10. Cat exposure induces both intra- and extracellular Hsp72: the role of adrenal hormones.

    Science.gov (United States)

    Fleshner, Monika; Campisi, Jay; Amiri, Leila; Diamond, David M

    2004-10-01

    Heat-shock proteins (Hsp) play an important role in stress physiology. Exposure to a variety of stressors will induce intracellular Hsp72, and this induction is believed to be beneficial for cell survival. In contrast, Hsp72 released during stress (extracellular Hsp72; eHsp72) activates pro-inflammatory responses. Clearly, physical stressors such as heat, cold, H(2)O(2), intense exercise and tail shock will induce both intra- and extracellular Hsp72. The current study tested whether a psychological stressor, cat exposure, would also trigger this response. In addition, the potential role of adrenal hormones in the Hsp72 response was examined. Adult, male Sprague Dawley rats were either adrenalectomized (ADX) or sham operated. Ten days post-recovery, rats were exposed to either a cat with no physical contact or control procedures (n = 5-6/group) for 2 h. Levels of intracellular Hsp72 were measured in the brain (frontal cortex, hippocampus, hypothalamus, dorsal vagal complex) and pituitary (ELISA). Levels of eHsp72 (ELISA) and corticosterone (RIA) were measured from serum obtained at the end of the 2-h stress period. Rats that were exposed to a cat had elevated intracellular Hsp72 in hypothalamus and dorsal vagal complex, and elevated eHsp72 and corticosterone in serum. Both the intra- and extracellular Hsp72 responses were blocked or attenuated by ADX. This study demonstrates that cat exposure can stimulate the Hsp72 response and that adrenal hormones contribute to this response.

  11. Tributyltin exposure induces gut microbiome dysbiosis with increased body weight gain and dyslipidemia in mice.

    Science.gov (United States)

    Guo, Hao; Yan, Haotian; Cheng, Dong; Wei, Xinglong; Kou, Ruirui; Si, Jiliang

    2018-05-03

    Gut microbiome dysbiosis plays a profound role in the pathogenesis of obesity and tributyltin (TBT) has been found as an environmental obesogen. However, whether TBT could disturb gut microbiome and the relationship between obesity induced by TBT exposure and alteration in gut microbiota are still unknown. In order to assess the association between them, mice were exposed to TBTCl (50 μg kg -1 ) once every three days from postnatal days (PNDs) 24 to 54. The results demonstrated that TBT exposure resulted in increased body weight gain, lager visceral fat accumulation and dyslipidemia in male mice on PND 84. Correspondingly, 16S rRNA gene sequencing revealed that TBT treatment decreased gut microbial species and perturbed the microbiome composition in mice. Furthermore, Pearson's corelation coefficient analysis showed a significantly negative correlation between the body weight and the alpha diversity of gut microbiome. These results suggested that TBT exposure could induce gut microbiome dysbiosis in mice, which might contribute to the obesity pathogenesis. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Effect decomposition in the presence of an exposure-induced mediator-outcome confounder

    Science.gov (United States)

    VanderWeele, Tyler J.; Vansteelandt, Stijn; Robins, James M.

    2014-01-01

    Methods from causal mediation analysis have generalized the traditional approach to direct and indirect effects in the epidemiologic and social science literature by allowing for interaction and non-linearities. However, the methods from the causal inference literature have themselves been subject to a major limitation in that the so-called natural direct and indirect effects that are employed are not identified from data whenever there is a variable that is affected by the exposure, which also confounds the relationship between the mediator and the outcome. In this paper we describe three alternative approaches to effect decomposition that give quantities that can be interpreted as direct and indirect effects, and that can be identified from data even in the presence of an exposure-induced mediator-outcome confounder. We describe a simple weighting-based estimation method for each of these three approaches, illustrated with data from perinatal epidemiology. The methods described here can shed insight into pathways and questions of mediation even when an exposure-induced mediator-outcome confounder is present. PMID:24487213

  13. Deoxynivalenol exposure induces autophagy/apoptosis and epigenetic modification changes during porcine oocyte maturation

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jun; Wang, Qiao-Chu; Zhu, Cheng-Cheng; Liu, Jun; Zhang, Yu [College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Cui, Xiang-Shun; Kim, Nam-Hyung [Department of Animal Science, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Sun, Shao-Chen, E-mail: sunsc@njau.edu.cn [College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China)

    2016-06-01

    Deoxynivalenol (DON) is a widespread trichothecene mycotoxin which contaminates agricultural staples and elicits a complex spectrum of toxic effects on humans and animals. It has been shown that DON impairs oocyte maturation, reproductive function and causes abnormal fetal development in mammals; however, the mechanisms remain unclear. In the present study, we investigate the possible reasons of the toxic effects of DON on porcine oocytes. Our results showed that DON significantly inhibited porcine oocyte maturation and disrupted meiotic spindle by reducing p-MAPK protein level, which caused retardation of cell cycle progression. In addition, up-regulated LC3 protein expression and aberrant Lamp2, LC3 and mTOR mRNA levels were observed with DON exposure, together with Annexin V-FITC staining assay analysis, these results indicated that DON treatment induced autophagy/apoptosis in porcine oocytes. We also showed that DON exposure increased DNA methylation level in porcine oocytes through altering DNMT3A mRNA levels. Histone methylation levels were also changed showing with increased H3K27me3 and H3K4me2 protein levels, and mRNA levels of their relative methyltransferase genes, indicating that epigenetic modifications were affected. Taken together, our results suggested that DON exposure reduced porcine oocytes maturation capability through affecting cytoskeletal dynamics, cell cycle, autophagy/apoptosis and epigenetic modifications. - Highlights: • DON exposure disrupted meiotic spindle by reducing p-MAPK expression. • DON exposure caused retardation of cell cycle progression in porcine oocytes. • DON triggered autophagy and early-apoptosis in porcine oocytes. • DON exposure led to aberrant epigenetic modifications in porcine oocytes.

  14. Deoxynivalenol exposure induces autophagy/apoptosis and epigenetic modification changes during porcine oocyte maturation

    International Nuclear Information System (INIS)

    Han, Jun; Wang, Qiao-Chu; Zhu, Cheng-Cheng; Liu, Jun; Zhang, Yu; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2016-01-01

    Deoxynivalenol (DON) is a widespread trichothecene mycotoxin which contaminates agricultural staples and elicits a complex spectrum of toxic effects on humans and animals. It has been shown that DON impairs oocyte maturation, reproductive function and causes abnormal fetal development in mammals; however, the mechanisms remain unclear. In the present study, we investigate the possible reasons of the toxic effects of DON on porcine oocytes. Our results showed that DON significantly inhibited porcine oocyte maturation and disrupted meiotic spindle by reducing p-MAPK protein level, which caused retardation of cell cycle progression. In addition, up-regulated LC3 protein expression and aberrant Lamp2, LC3 and mTOR mRNA levels were observed with DON exposure, together with Annexin V-FITC staining assay analysis, these results indicated that DON treatment induced autophagy/apoptosis in porcine oocytes. We also showed that DON exposure increased DNA methylation level in porcine oocytes through altering DNMT3A mRNA levels. Histone methylation levels were also changed showing with increased H3K27me3 and H3K4me2 protein levels, and mRNA levels of their relative methyltransferase genes, indicating that epigenetic modifications were affected. Taken together, our results suggested that DON exposure reduced porcine oocytes maturation capability through affecting cytoskeletal dynamics, cell cycle, autophagy/apoptosis and epigenetic modifications. - Highlights: • DON exposure disrupted meiotic spindle by reducing p-MAPK expression. • DON exposure caused retardation of cell cycle progression in porcine oocytes. • DON triggered autophagy and early-apoptosis in porcine oocytes. • DON exposure led to aberrant epigenetic modifications in porcine oocytes.

  15. Occupational Styrene Exposure Induces Stress-Responsive Genes Involved in Cytoprotective and Cytotoxic Activities

    Science.gov (United States)

    Strafella, Elisabetta; Bracci, Massimo; Staffolani, Sara; Manzella, Nicola; Giantomasi, Daniele; Valentino, Matteo; Amati, Monica; Tomasetti, Marco; Santarelli, Lory

    2013-01-01

    Objective The aim of this study was to evaluate the expression of a panel of genes involved in toxicology in response to styrene exposure at levels below the occupational standard setting. Methods Workers in a fiber glass boat industry were evaluated for a panel of stress- and toxicity-related genes and associated with biochemical parameters related to hepatic injury. Urinary styrene metabolites (MA+PGA) of subjects and environmental sampling data collected for air at workplace were used to estimate styrene exposure. Results Expression array analysis revealed massive upregulation of genes encoding stress-responsive proteins (HSPA1L, EGR1, IL-6, IL-1β, TNSF10 and TNFα) in the styrene-exposed group; the levels of cytokines released were further confirmed in serum. The exposed workers were then stratified by styrene exposure levels. EGR1 gene upregulation paralleled the expression and transcriptional protein levels of IL-6, TNSF10 and TNFα in styrene exposed workers, even at low level. The activation of the EGR1 pathway observed at low-styrene exposure was associated with a slight increase of hepatic markers found in highly exposed subjects, even though they were within normal range. The ALT and AST levels were not affected by alcohol consumption, and positively correlated with urinary styrene metabolites as evaluated by multiple regression analysis. Conclusion The pro-inflammatory cytokines IL-6 and TNFα are the primary mediators of processes involved in the hepatic injury response and regeneration. Here, we show that styrene induced stress responsive genes involved in cytoprotection and cytotoxicity at low-exposure, that proceed to a mild subclinical hepatic toxicity at high-styrene exposure. PMID:24086524

  16. The relationship between long-term sunlight radiation and cognitive decline in the REGARDS cohort study

    Science.gov (United States)

    Kent, Shia T.; Kabagambe, Edmond K.; Wadley, Virginia G.; Howard, Virginia J.; Crosson, William L.; Al-Hamdan, Mohammad Z.; Judd, Suzanne E.; Peace, Fredrick; McClure, Leslie A.

    2014-04-01

    Sunlight may be related to cognitive function through vitamin D metabolism or circadian rhythm regulation. The analysis presented here sought to test whether ground and satellite measures of solar radiation are associated with cognitive decline. The study used a 15-year residential history merged with satellite and ground monitor data to determine sunlight (solar radiation) and air temperature exposure for a cohort of 19,896 cognitively intact black and white participants aged 45+ from the 48 contiguous United States. Exposures of 15, 10, 5, 2, and 1-year were used to predict cognitive status at the most recent assessment in logistic regression models; 1-year insolation and maximum temperatures were chosen as exposure measures. Solar radiation interacted with temperature, age, and gender in its relationships with incident cognitive impairment. After adjustment for covariates, the odds ratio (OR) of cognitive decline for solar radiation exposure below the median vs above the median in the 3rd tertile of maximum temperatures was 1.88 (95 % CI: 1.24, 2.85), that in the 2nd tertile was 1.33 (95 % CI: 1.09, 1.62), and that in the 1st tertile was 1.22 (95 % CI: 0.92, 1.60). We also found that participants under 60 years old had an OR = 1.63 (95 % CI: 1.20, 2.22), those 60-80 years old had an OR = 1.18 (95 % CI: 1.02, 1.36), and those over 80 years old had an OR = 1.05 (0.80, 1.37). Lastly, we found that males had an OR = 1.43 (95 % CI: 1.22, 1.69), and females had an OR = 1.02 (0.87, 1.20). We found that lower levels of solar radiation were associated with increased odds of incident cognitive impairment.

  17. Acute Acrolein Exposure Induces Impairment of Vocal Fold Epithelial Barrier Function.

    Science.gov (United States)

    Liu, Xinxin; Zheng, Wei; Sivasankar, M Preeti

    2016-01-01

    Acrolein is a ubiquitous pollutant abundant in cigarette smoke, mobile exhaust, and industrial waste. There is limited literature on the effects of acrolein on vocal fold tissue, although there are clinical reports of voice changes after pollutant exposures. Vocal folds are responsible for voice production. The overall objective of this study was to investigate the effects of acrolein exposure on viable, excised vocal fold epithelial tissue and to characterize the mechanism underlying acrolein toxicity. Vocal fold epithelia were studied because they form the outermost layer of the vocal folds and are a primary recipient of inhaled pollutants. Porcine vocal fold epithelia were exposed to 0, 50, 100, 500, 900 or 1300 μM of acrolein for 3 hours; the metabolic activity, epithelial resistance, epithelial permeability, tight junction protein (occludin and claudin 3) expression, cell membrane integrity and lipid peroxidation were investigated. The data demonstrated that acrolein exposure at 500 μM significantly reduced vocal fold epithelial metabolic activity by 27.2% (p≤0.001). Incubation with 100 μM acrolein caused a marked increase in epithelial permeability by 130.5% (pacrolein-treated samples, the cell membrane integrity was significantly damaged with a 45.6% increase of lipid peroxidation as compared to controls (pacrolein exposure impairs vocal fold epithelial barrier integrity. Lipid peroxidation-induced cell membrane damage may play an important role in reducing the barrier function of the epithelium.

  18. Rat hippocampal alterations could underlie behavioral abnormalities induced by exposure to moderate noise levels.

    Science.gov (United States)

    Uran, S L; Aon-Bertolino, M L; Caceres, L G; Capani, F; Guelman, L R

    2012-08-30

    Noise exposure is known to affect auditory structures in living organisms. However, it should not be ignored that many of the effects of noise are extra-auditory. Previous findings of our laboratory demonstrated that noise was able to induce behavioral alterations that are mainly related to the cerebellum (CE) and the hippocampus (HC). Therefore, the aim of this work was to reveal new data about the vulnerability of developing rat HC to moderate noise levels through the assessment of potential histological changes and hippocampal-related behavioral alterations. Male Wistar rats were exposed to noise (95-97 dB SPL, 2h daily) either for 1 day (acute noise exposure, ANE) or between postnatal days 15 and 30 (sub-acute noise exposure, SANE). Hippocampal histological evaluation as well as short (ST) and long term (LT) habituation and recognition memory assessments were performed. Results showed a mild disruption in the different hippocampal regions after ANE and SANE schemes, along with significant behavioral abnormalities. These data suggest that exposure of developing rats to noise levels of moderate intensity is able to trigger changes in the HC, an extra-auditory structure of the Central Nervous System (CNS), that could underlie the observed behavioral effects. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Dynamic light absorption of biomass-burning organic carbon photochemically aged under natural sunlight

    Science.gov (United States)

    Zhong, M.; Jang, M.

    2014-02-01

    Wood-burning aerosol produced under smoldering conditions was photochemically aged with different relative humidity (RH) and NOx conditions using a 104 m3 dual outdoor chamber under natural sunlight. Light absorption of organic carbon (OC) was measured over the course of photooxidation using a UV-visible spectrometer connected to an integrating sphere. At high RH, the color decayed rapidly. NOx slightly prolonged the color of wood smoke, suggesting that NOx promotes the formation of chromophores via secondary processes. Overall, the mass absorption cross section (integrated between 280 and 600 nm) of OC increased by 11-54% (except high RH) in the morning and then gradually decreased by 19-68% in the afternoon. This dynamic change in light absorption of wood-burning OC can be explained by two mechanisms: chromophore formation and sunlight bleaching. To investigate the effect of chemical transformation on light absorption, wood smoke particles were characterized using various spectrometers. The intensity of fluorescence, which is mainly related to polycyclic aromatic hydrocarbons (PAHs), rapidly decreased with time, indicating the potential bleaching of PAHs. A decline of levoglucosan concentrations evinced the change of primary organic aerosol with time. The aerosol water content measured by Fourier transform infrared spectroscopy showed that wood-burning aerosol became less hygroscopic as photooxidation proceeded. A similar trend in light absorption changes has been observed in ambient smoke aerosol originating from the 2012 County Line wildfire in Florida. We conclude that the biomass-burning OC becomes less light absorbing after 8-9 h sunlight exposure compared to fresh wood-burning OC.

  20. Dynamic light absorption of biomass burning organic carbon photochemically aged under natural sunlight

    Science.gov (United States)

    Zhong, M.; Jang, M.

    2013-08-01

    Wood burning aerosol produced under smoldering conditions was photochemically aged with different relative humidity (RH) and NOx conditions using a 104 m3 dual outdoor chamber under natural sunlight. Light absorption of organic carbon (OC) was measured over the course of photooxidation using a UV-visible spectrometer connected to an integrating sphere. At high RH, the color decayed rapidly. NOx slightly prolonged the color of wood smoke, suggesting that NOx promotes the formation of chromophores via secondary processes. Overall, the mass absorption cross-section (integrated between 280 nm and 600 nm) of OC increased by 11-54% (except high RH) in the morning and then gradually decreased by 19-68% in the afternoon. This dynamic change in light absorption of wood burning OC can be explained by two mechanisms: chromophore formation and sunlight bleaching. To investigate the effect of chemical transformation on light absorption, wood smoke particles were characterized using various spectrometers. The intensity of fluorescence, which is mainly related to polycyclic aromatic hydrocarbons (PAHs), rapidly decreased with time indicating the potential bleaching of PAHs. A decline of levoglucosan concentrations evinced the change of POA with time. The aerosol water content measured by Fourier transform infrared spectroscopy showed that wood burning aerosol became less hygroscopic as photooxidation proceeded. A similar trend in light absorption changes has been observed in ambient smoke aerosol originating from the 2012 County Line Wildfire in Florida. We conclude that the biomass burning OC becomes less light absorbing after 8-9 h sunlight exposure compared to fresh wood burning OC.

  1. Chronic exposure to Tributyltin induces brain functional damage in juvenile common carp (Cyprinus carpio.

    Directory of Open Access Journals (Sweden)

    Zhi-Hua Li

    Full Text Available The aim of the present study was to investigate the effect of Tributyltin (TBT on brain function and neurotoxicity of freshwater teleost. The effects of long-term exposure to TBT on antioxidant related indices (MDA, malondialdehyde; SOD, superoxide dismutase; CAT, catalase; GR, glutathione reductase; GPx, glutathione peroxidase, Na+-K+-ATPase and neurological parameters (AChE, acetylcholinesterase; MAO, monoamine oxidase; NO, nitric oxide in the brain of common carp were evaluated. Fish were exposed to sublethal concentrations of TBT (75 ng/L, 0.75 μg/L and 7.5 μg/L for 15, 30, and 60 days. Based on the results, a low level and short-term TBT-induced stress could not induce the notable responses of the fish brain, but long-term exposure (more than 15 days to TBT could lead to obvious physiological-biochemical responses (based on the measured parameters. The results also strongly indicated that neurotoxicity of TBT to fish. Thus, the measured physiological responses in fish brain could provide useful information to better understand the mechanisms of TBT-induced bio-toxicity.

  2. Chronic Exposure to Tributyltin Induces Brain Functional Damage in Juvenile Common Carp (Cyprinus carpio)

    Science.gov (United States)

    Li, Zhi-Hua; Li, Ping; Shi, Ze-Chao

    2015-01-01

    The aim of the present study was to investigate the effect of Tributyltin (TBT) on brain function and neurotoxicity of freshwater teleost. The effects of long-term exposure to TBT on antioxidant related indices (MDA, malondialdehyde; SOD, superoxide dismutase; CAT, catalase; GR, glutathione reductase; GPx, glutathione peroxidase), Na+-K+-ATPase and neurological parameters (AChE, acetylcholinesterase; MAO, monoamine oxidase; NO, nitric oxide) in the brain of common carp were evaluated. Fish were exposed to sublethal concentrations of TBT (75 ng/L, 0.75 μg/L and 7.5 μg/L) for 15, 30, and 60 days. Based on the results, a low level and short-term TBT-induced stress could not induce the notable responses of the fish brain, but long-term exposure (more than 15 days) to TBT could lead to obvious physiological-biochemical responses (based on the measured parameters). The results also strongly indicated that neurotoxicity of TBT to fish. Thus, the measured physiological responses in fish brain could provide useful information to better understand the mechanisms of TBT-induced bio-toxicity. PMID:25879203

  3. Chronic exposure to Tributyltin induces brain functional damage in juvenile common carp (Cyprinus carpio).

    Science.gov (United States)

    Li, Zhi-Hua; Li, Ping; Shi, Ze-Chao

    2015-01-01

    The aim of the present study was to investigate the effect of Tributyltin (TBT) on brain function and neurotoxicity of freshwater teleost. The effects of long-term exposure to TBT on antioxidant related indices (MDA, malondialdehyde; SOD, superoxide dismutase; CAT, catalase; GR, glutathione reductase; GPx, glutathione peroxidase), Na+-K+-ATPase and neurological parameters (AChE, acetylcholinesterase; MAO, monoamine oxidase; NO, nitric oxide) in the brain of common carp were evaluated. Fish were exposed to sublethal concentrations of TBT (75 ng/L, 0.75 μg/L and 7.5 μg/L) for 15, 30, and 60 days. Based on the results, a low level and short-term TBT-induced stress could not induce the notable responses of the fish brain, but long-term exposure (more than 15 days) to TBT could lead to obvious physiological-biochemical responses (based on the measured parameters). The results also strongly indicated that neurotoxicity of TBT to fish. Thus, the measured physiological responses in fish brain could provide useful information to better understand the mechanisms of TBT-induced bio-toxicity.

  4. Could driving safety be compromised by noise exposure at work and noise-induced hearing loss?

    Science.gov (United States)

    Picard, Michel; Girard, Serge André; Courteau, Marilène; Leroux, Tony; Larocque, Richard; Turcotte, Fernand; Lavoie, Michel; Simard, Marc

    2008-10-01

    A study was conducted to verify if there is an association between occupational noise exposure, noise-induced hearing loss and driving safety expanding on previous findings by Picard, et al. (2008) that the two factors did increase accident risk in the workplace. This study was made possible when driving records of all Quebec drivers were made available by the Societe de l'assurance automobile du Quebec (SAAQ is the state monopoly responsible for the provision of motor vehicle insurance and the compensation of victims of traffic accidents). These records were linked with personal records maintained by the Quebec National Institute of Public Health as part of its mission to prevent noise induced hearing loss in the workplace. Individualized information on occupational noise exposure and hearing sensitivity was available for 46,030 male workers employed in noisy industries who also held a valid driver's permit. The observation period is of five years duration, starting with the most recent audiometric examination. The associations between occupational noise exposure levels, hearing status, and personal driving record were examined by log-binomial regression on data adjusted for age and duration of exposure. Daily noise exposures and bilateral average hearing threshold levels at 3, 4, and 6 kHz were used as independent variables while the dependent variables were 1) the number of motor vehicle accidents experienced by participants during the study period and 2) participants' records of registered traffic violations of the highway safety code. The findings are reported as prevalence ratios (PRs) with their 95% confidence intervals (CIs). Attributable numbers of events were computed with the relevant PRs, lesser-noise, exposed workers and those with normal hearing levels making the group of reference. Adjusting for age confirmed that experienced workers had fewer traffic accidents. The data show that occupational noise exposure and hearing loss have the same effect on

  5. Oral imazalil exposure induces gut microbiota dysbiosis and colonic inflammation in mice.

    Science.gov (United States)

    Jin, Cuiyuan; Zeng, Zhaoyang; Fu, Zhengwei; Jin, Yuanxiang

    2016-10-01

    The fungicide imazalil (IMZ) is used extensively in vegetable and fruit plantations and as a post-harvest treatment to avoid rot. Here, we revealed that ingestion of 25, 50 and 100 mg IMZ kg(-1) body weight for 28 d induced gut microbiota dysbiosis and colonic inflammation in mice. The relative abundance of Bacteroidetes, Firmicutes and Actinobacteria in the cecal contents decreased significantly after exposure to 100 mg kg(-1) IMZ for 28 d. In feces, the relative abundance in Bacteroidetes, Firmicutes and Actinobacteria decreased significantly after being exposed to 100 mg kg(-1) IMZ for 1, 14 and 7 d, respectively. High throughput sequencing of the V3-V4 region of the bacterial 16S rRNA gene revealed a significant reduction in the richness and diversity of microbiota in cecal contents and feces of IMZ-treated mice. Operational taxonomic units (OTUs) analysis identified 49.3% of OTUs changed in cecal contents, while 55.6% of OTUs changed in the feces after IMZ exposure. Overall, at the phylum level, the relative abundance of Firmicutes, Proteobacteria and Actinobacteria increased and that of Bacteroidetes decreased in IMZ-treated groups. At the genus level, the abundance of Lactobacillus and Bifidobacterium decreased while those of Deltaproteobacteria and Desulfovibrio increased in response to IMZ exposure. In addition, it was observed that IMZ exposure could induce colonic inflammation characterized by infiltration of inflammatory cells, elevated levels of lipocalin-2 (lcn-2) in the feces, and increased mRNA levels of Tnf-α, IL-1β, IL-22 and IFN-γ in the colon. Our findings strongly suggest that ingestion of IMZ has some risks to human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Exposure to tobacco-derived materials induces overproduction of secreted proteinases in mast cells

    International Nuclear Information System (INIS)

    Small-Howard, Andrea; Turner, Helen

    2005-01-01

    Mast cells reside at interfaces with the environment, including the mucosa of the respiratory and gastrointestinal tracts. This localization exposes mast cells to inhaled, or ingested, environmental challenges. In the airways of smokers, resident immune cells will be in contact with the condensed components of cigarette smoke. Mast cells are of particular interest due to their ability to promote airway remodeling and mucus hypersecretion. Clinical data show increased levels of mast cell-secreted tryptase and increased numbers of degranulated mast cells in the lavage and bronchial tissue of smokers. Since mast cell-secreted proteinases (MCPTs), including tryptases, contribute to pathological airway remodeling, we investigated the relationship between mast cell proteinases and smoke exposure. We exposed a mast cell line to cigarette smoke condensate (CSC). We show that CSC exposure increases MCPT levels in mast cells using an assay for tryptase-type MCPT activity. We hypothesized that this increase in MCPT activity reflects a CSC-induced increase in the cytosolic pool of proteinase molecules, via stimulation of MCPT transcription. Transcript array data suggested that mRNA changes in response to CSC were limited in number and peaked after 3 h of CSC exposure. However, we noted marked transcriptional regulation of several MCPT genes. CSC-induced changes in the mRNA levels for MCPTs were confirmed using quantitative RT-PCR. Taken together, our data suggest that chronic exposure to cigarette smoke up-regulates MCPT levels in mast cells at both the protein and the mRNA level. We suggest that the pathological airway remodeling that has been described in clinical studies of smoke inhalation may be attributable to MCPT overproduction in vivo

  7. Epi-genetics modifications induced by a depleted uranium exposure in the zebra fish

    Energy Technology Data Exchange (ETDEWEB)

    Gombeau, K.; Pereira, S.; Adam-Guillermin, C. [IRSN/PRP-ENV/SERIS/LECO (France); Bourdineaud, J.P. [UMR CNRS 5805 EPOC (France); Ravanat, J.L. [INAC/Scib UMR E3 CEA-UJF (France)

    2014-07-01

    The work presented here integrates in the general framework of assessment of effects of chronic exposure to low doses of radionuclides. This evaluation necessarily involves the study of the mechanisms of toxic action at the cellular or subcellular level, in order to better understand the processes of propagation of effects to the level of the populations or ecosystems. As such, the question of the mechanisms underlying the trans-generational effects and the adaptive capacity of organisms is central, both in humans and in animal species. Epigenetic refer to changes in gene function that do not involve changes in DNA sequence, and which are transmitted in a hereditary manner by mitosis or meiosis. The latter plays a key role in these trans-generational effects. Among these changes, DNA-methylation is one of the most studied epigenetic parameters. This work is part of a PhD, included in the European COMET project (Euratom 7. Framework Program), and focuses on epigenetic modifications induced in zebra fish after a chronic exposure to radionuclides. Male and female fishes were exposed to 2 and 20 μg.L{sup -1} of depleted uranium for 24 days. After 7 and 24 days of exposure, brain, gonads, and eyes were collected in order to study changes in DNA methylation. In addition, genotoxicity was measured by the γH2AX assay. The overall changes in DNA methylation were studied by AFLP-MS and HPLC-MS, in order to know if the exposure to depleted uranium changes the global status of DNA methylation. We have found a decrease in the global level of methylation in the eyes of males after 24 days of exposure, the diminution being much more important and significant at the higher concentration of exposure (11.79 ± 3.62 against 52.43 ± 3.01 for controls) This study will be refined by analyzing the methylation of specific regions of the genome, because it represent the sequences of genes involved in major physiological functions and that may be subject to variations in the methylation

  8. Low Level Laser Therapy Reduces the Development of Lung Inflammation Induced by Formaldehyde Exposure.

    Directory of Open Access Journals (Sweden)

    Cristiane Miranda da Silva

    Full Text Available Lung diseases constitute an important public health problem and its growing level of concern has led to efforts for the development of new therapies, particularly for the control of lung inflammation. Low Level Laser Therapy (LLLT has been highlighted as a non-invasive therapy with few side effects, but its mechanisms need to be better understood and explored. Considering that pollution causes several harmful effects on human health, including lung inflammation, in this study, we have used formaldehyde (FA, an environmental and occupational pollutant, for the induction of neutrophilic lung inflammation. Our objective was to investigate the local and systemic effects of LLLT after FA exposure. Male Wistar rats were exposed to FA (1% or vehicle (distillated water during 3 consecutive days and treated or not with LLLT (1 and 5 hours after each FA exposure. Non-manipulated rats were used as control. 24 h after the last FA exposure, we analyzed the local and systemic effects of LLLT. The treatment with LLLT reduced the development of neutrophilic lung inflammation induced by FA, as observed by the reduced number of leukocytes, mast cells degranulated, and a decreased myeloperoxidase activity in the lung. Moreover, LLLT also reduced the microvascular lung permeability in the parenchyma and the intrapulmonary bronchi. Alterations on the profile of inflammatory cytokines were evidenced by the reduced levels of IL-6 and TNF-α and the elevated levels of IL-10 in the lung. Together, our results showed that LLLT abolishes FA-induced neutrophilic lung inflammation by a reduction of the inflammatory cytokines and mast cell degranulation. This study may provide important information about the mechanisms of LLLT in lung inflammation induced by a pollutant.

  9. Cockle Temperature Exposure Lab Experiment (2016)

    Data.gov (United States)

    U.S. Environmental Protection Agency — We carried out a lab experiment in which we exposed cockles to a range of air temperatures to simulate the physiological rigors of exposure to sunlight and air at...

  10. Hypoxia-induced pulmonary arterial hypertension augments lung injury and airway reactivity caused by ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Zychowski, Katherine E.; Lucas, Selita N.; Sanchez, Bethany; Herbert, Guy; Campen, Matthew J., E-mail: mcampen@salud.unm.edu

    2016-08-15

    Ozone (O{sub 3})-related cardiorespiratory effects are a growing public health concern. Ground level O{sub 3} can exacerbate pre-existing respiratory conditions; however, research regarding therapeutic interventions to reduce O{sub 3}-induced lung injury is limited. In patients with chronic obstructive pulmonary disease, hypoxia-associated pulmonary hypertension (HPH) is a frequent comorbidity that is difficult to treat clinically, yet associated with increased mortality and frequency of exacerbations. In this study, we hypothesized that established HPH would confer vulnerability to acute O{sub 3} pulmonary toxicity. Additionally, we tested whether improvement of pulmonary endothelial barrier integrity via rho-kinase inhibition could mitigate pulmonary inflammation and injury. To determine if O{sub 3} exacerbated HPH, male C57BL/6 mice were subject to either 3 weeks continuous normoxia (20.9% O{sub 2}) or hypoxia (10.0% O{sub 2}), followed by a 4-h exposure to either 1 ppm O{sub 3} or filtered air (FA). As an additional experimental intervention fasudil (20 mg/kg) was administered intraperitoneally prior to and after O{sub 3} exposures. As expected, hypoxia significantly increased right ventricular pressure and hypertrophy. O{sub 3} exposure in normoxic mice caused lung inflammation but not injury, as indicated by increased cellularity and edema in the lung. However, in hypoxic mice, O{sub 3} exposure led to increased inflammation and edema, along with a profound increase in airway hyperresponsiveness to methacholine. Fasudil administration resulted in reduced O{sub 3}-induced lung injury via the enhancement of pulmonary endothelial barrier integrity. These results indicate that increased pulmonary vascular pressure may enhance lung injury, inflammation and edema when exposed to pollutants, and that enhancement of pulmonary endothelial barrier integrity may alleviate such vulnerability. - Highlights: • Environmental exposures can exacerbate chronic obstructive

  11. Hypoxia-induced pulmonary arterial hypertension augments lung injury and airway reactivity caused by ozone exposure

    International Nuclear Information System (INIS)

    Zychowski, Katherine E.; Lucas, Selita N.; Sanchez, Bethany; Herbert, Guy; Campen, Matthew J.

    2016-01-01

    Ozone (O 3 )-related cardiorespiratory effects are a growing public health concern. Ground level O 3 can exacerbate pre-existing respiratory conditions; however, research regarding therapeutic interventions to reduce O 3 -induced lung injury is limited. In patients with chronic obstructive pulmonary disease, hypoxia-associated pulmonary hypertension (HPH) is a frequent comorbidity that is difficult to treat clinically, yet associated with increased mortality and frequency of exacerbations. In this study, we hypothesized that established HPH would confer vulnerability to acute O 3 pulmonary toxicity. Additionally, we tested whether improvement of pulmonary endothelial barrier integrity via rho-kinase inhibition could mitigate pulmonary inflammation and injury. To determine if O 3 exacerbated HPH, male C57BL/6 mice were subject to either 3 weeks continuous normoxia (20.9% O 2 ) or hypoxia (10.0% O 2 ), followed by a 4-h exposure to either 1 ppm O 3 or filtered air (FA). As an additional experimental intervention fasudil (20 mg/kg) was administered intraperitoneally prior to and after O 3 exposures. As expected, hypoxia significantly increased right ventricular pressure and hypertrophy. O 3 exposure in normoxic mice caused lung inflammation but not injury, as indicated by increased cellularity and edema in the lung. However, in hypoxic mice, O 3 exposure led to increased inflammation and edema, along with a profound increase in airway hyperresponsiveness to methacholine. Fasudil administration resulted in reduced O 3 -induced lung injury via the enhancement of pulmonary endothelial barrier integrity. These results indicate that increased pulmonary vascular pressure may enhance lung injury, inflammation and edema when exposed to pollutants, and that enhancement of pulmonary endothelial barrier integrity may alleviate such vulnerability. - Highlights: • Environmental exposures can exacerbate chronic obstructive pulmonary disease (COPD). • It is unknown if comorbid

  12. Roles of Saccharomyces cerevisiae DNA polymerases Poleta and Polzeta in response to irradiation by simulated sunlight.

    Science.gov (United States)

    Kozmin, Stanislav G; Pavlov, Youri I; Kunkel, Thomas A; Sage, Evelyne

    2003-08-01

    Sunlight causes lesions in DNA that if unrepaired and inaccurately replicated by DNA polymerases yield mutations that result in skin cancer in humans. Two enzymes involved in translesion synthesis (TLS) of UV-induced photolesions are DNA polymerase eta (Poleta) and polymerase zeta (Polzeta), encoded by the RAD30A and REV3 genes, respectively. Previous studies have investigated the TLS roles of these polymerases in human and yeast cells irradiated with monochromatic, short wavelength UVC radiation (254 nm). However, less is known about cellular responses to solar radiation, which is of higher and mixed wavelengths (310-1100 nm) and produces a different spectrum of DNA lesions, including Dewar photoproducts and oxidative lesions. Here we report on the comparative cytotoxic and mutagenic effects of simulated sunlight (SSL) and UVC radiation on yeast wild-type, rad30Delta, rev3Delta and rev3Delta rad30Delta strains. The results with SSL support several previous interpretations on the roles of these two polymerases in TLS of photodimers and (6-4) photoproducts derived from studies with UVC. They further suggest that Poleta participates in the non-mutagenic bypass of SSL-dependent cytosine-containing Dewar photoproducts and 8-oxoguanine, while Polzeta is mainly responsible for the mutagenic bypass of all types of Dewar photoproducts. They also suggest that in the absence of Polzeta, Poleta contributes to UVC- and SSL-induced mutagenesis, possibly by the bypass of photodimers containing deaminated cytosine.

  13. Resistance to asbestos-induced apoptosis with continuous exposure to crocidolite on a human T cell

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Megumi [Department of Biofunctional Chemistry, Graduate School of Natural Science and Technology, Okayama University, 1-1-1 Tsushima-Naka, Okayama 700-8530 (Japan); Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Yamamoto, Shoko [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Chen, Ying [Division of Pneumoconiosis, School of Public Health, China Medical University, 92 North 2nd, Heping District, Shenyang 110001 (China); Kumagai-Takei, Naoko [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Hayashi, Hiroaki [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Department of Dermatology, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Matsuzaki, Hidenori; Lee, Suni; Hatayama, Tamayo; Miyahara, Naomi; Katoh, Minako [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Hiratsuka, Juni-ichi [Department of Radiation Oncology, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Nishimura, Yasumitsu [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan); Otsuki, Takemi, E-mail: takemi@med.kawasaki-m.ac.jp [Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192 (Japan)

    2012-07-01

    We have been investigating the immunological effects of asbestos. The establishment of a low-dose and continuously exposed human T cell line, HTLV-1 immortalized MT-2, to chrysotile (CB) revealed reduction of CXCR3 chemokine receptor and production of IFN-{gamma} that caused a decline of tumor immunity. These effects were coupled with upregulation of IL-10, TGF-{beta}, and BCL-2 in asbestos-exposed patients. To observe the immunological effects of crocidolite (CR) on human T cells, a trial to establish a low-dose and continuously exposed model was conducted and compared with a previously reported CB-exposed model (MT-2CB). Transient exposure of MT-2 original cells to CB or CR induced a similar level of apoptosis and growth inhibition. The establishment of a continuously exposed subline to CR (MT-2CR) revealed resistance against CR-induced apoptosis and upregulation of the BCL-2/BAX ratio similar to that recorded for MT-2CB. Both sublines showed reduced production of IFN-{gamma}, TNF-{alpha}, and IL-6 with increased IL-10. cDNA microarray with network/pathway analyses focusing on transcription factors revealed that many similar factors related to cell proliferation were involved following continuous exposure to asbestos in both MT-2CB and MT-2CR. These results indicate that both CB and CR fibers affect human T cells with similar degrees even though the carcinogenic activity of these substances differs due to their chemical and physical forms. Trials to identify early detection markers for asbestos exposure or the occurrence of asbestos-inducing malignancies using these findings may lead to the development of clinical tools for asbestos-related diseases and chemoprevention that modifies the reduced tumor immunity. - Highlights: Black-Right-Pointing-Pointer Comparison of effects of chrysotile and crocidolite on human T cell was done. Black-Right-Pointing-Pointer Both fibers caused apoptosis of T cells by transient exposure. Black-Right-Pointing-Pointer T cells

  14. HPRT gene locus mutation in peripheral blood lymphocytes induced by internal exposure to radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Jingyong, Zhao; Yongzhong, Xu; Tao, Zhao; Fengmei, Cui; Liuyi, Wang; Qinhua, Lao [Suzhou Univ., Suzhou (China). Radiation Medicine Department

    2001-07-01

    HPRT gene locus mutation in peripheral blood lymphocytes induced by internal exposure to radionuclides was performed and the relationships between mutation frequency and dose were studied. Rats were injected intravenously with radionuclides, the blood was sampled at different time after injection; HPRT gene locus mutation frequency (GMF) were examined by methods of multi-nucleus cell and Brdurd assay, working out the Dose-response function. GMF rose with the increase of dose and dose-rates and were clearly interrelated. The HPRT gene locus mutation is very sensitive to radiation and may be used as a biological dosimeter.

  15. [DNA damage in human pleural mesothelial cells induced by exposure to carbon nanotubes].

    Science.gov (United States)

    Ogasawara, Yuki; Umezu, Noriaki; Ishii, Kazuyuki

    2012-01-01

    Nanomaterials are currently used in electronics, industrial materials, cosmetics, and medicine because they have useful physicochemical properties, such as strength, conductivity, durability, and chemical stability. As these materials have become widespread, many questions have arisen regarding their effects on health and the environment. In particular, recent studies have demonstrated that carbon nanotubes (CNTs) cause significant inflammation and mesothelioma in vivo. In this study, we investigated the potential risk posed by singlewalled carbon nanotube (SWCNT) and multiwalled carbon nanotube (MWCNT) exposure in human pleural mesothelial cells. CNT cytotoxicity was determined by a trypan blue exclusion assay, and DNA damage was detected by an alkaline comet assay. The concentration of 8-oxodeoxyguanosine (8-OHdG) in DNA was measured by high perhormance liquid chromatography with electrochemical detection. The expression of base excision repair enzymes in the cell was estimated by immunoblot analysis. We observed inhibitory effects on cell proliferation and the induction of DNA damage following exposure of cells to purified CNTs that were suspended in dispersion medium. However, accumulation of 8-OHdG in DNA was not found. In addition, the expression levels of base excision enzymes that are involved in hOGG1, hMTH1, and MYH in MeT-5A cells remained unchanged for 24 h after carbon nanotube exposure. CNTs significantly inhibit cell proliferation and decrease DNA damage in human pleural mesothelial cells. Our results indicate that the mechanism of CNT-induced genotoxicity is different from that following exposure to reactive oxygen species, which causes oxidative DNA modifications and 8-OHdG production. Further investigation is required to characterize the specific DNA mutations that occur following CNT exposure.

  16. Repeated cocaine exposure facilitates the expression of incentive motivation and induces habitual control in rats.

    Directory of Open Access Journals (Sweden)

    Kimberly H LeBlanc

    Full Text Available There is growing evidence that mere exposure to drugs can induce long-term alterations in the neural systems that mediate reward processing, motivation, and behavioral control, potentially causing the pathological pursuit of drugs that characterizes the addicted state. The incentive sensitization theory proposes that drug exposure potentiates the influence of reward-paired cues on behavior. It has also been suggested that drug exposure biases action selection towards the automatic execution of habits and away from more deliberate goal-directed control. The current study investigated whether rats given repeated exposure to peripherally administered cocaine would show alterations in incentive motivation (assayed using the Pavlovian-to-instrumental transfer (PIT paradigm or habit formation (assayed using sensitivity to reward devaluation. After instrumental and Pavlovian training for food pellet rewards, rats were given 6 daily injections of cocaine (15 mg/kg, IP or saline, followed by a 10-d period of rest. Consistent with the incentive sensitization theory, cocaine-treated rats showed stronger cue-evoked lever pressing than saline-treated rats during the PIT test. The same rats were then trained on a new instrumental action with a new food pellet reward before undergoing a reward devaluation testing. Although saline-treated rats exhibited sensitivity to reward devaluation, indicative of goal-directed performance, cocaine-treated rats were insensitive to this treatment, suggesting a reliance on habitual processes. These findings, when taken together, indicate that repeated exposure to cocaine can cause broad alterations in behavioral control, spanning both motivational and action selection processes, and could therefore help explain aberrations of decision-making that underlie drug addiction.

  17. Repeated cocaine exposure facilitates the expression of incentive motivation and induces habitual control in rats.

    Science.gov (United States)

    LeBlanc, Kimberly H; Maidment, Nigel T; Ostlund, Sean B

    2013-01-01

    There is growing evidence that mere exposure to drugs can induce long-term alterations in the neural systems that mediate reward processing, motivation, and behavioral control, potentially causing the pathological pursuit of drugs that characterizes the addicted state. The incentive sensitization theory proposes that drug exposure potentiates the influence of reward-paired cues on behavior. It has also been suggested that drug exposure biases action selection towards the automatic execution of habits and away from more deliberate goal-directed control. The current study investigated whether rats given repeated exposure to peripherally administered cocaine would show alterations in incentive motivation (assayed using the Pavlovian-to-instrumental transfer (PIT) paradigm) or habit formation (assayed using sensitivity to reward devaluation). After instrumental and Pavlovian training for food pellet rewards, rats were given 6 daily injections of cocaine (15 mg/kg, IP) or saline, followed by a 10-d period of rest. Consistent with the incentive sensitization theory, cocaine-treated rats showed stronger cue-evoked lever pressing than saline-treated rats during the PIT test. The same rats were then trained on a new instrumental action with a new food pellet reward before undergoing a reward devaluation testing. Although saline-treated rats exhibited sensitivity to reward devaluation, indicative of goal-directed performance, cocaine-treated rats were insensitive to this treatment, suggesting a reliance on habitual processes. These findings, when taken together, indicate that repeated exposure to cocaine can cause broad alterations in behavioral control, spanning both motivational and action selection processes, and could therefore help explain aberrations of decision-making that underlie drug addiction.

  18. Does uranium exposure induce oxidative stress and genotoxicity in the teleostean Danio rerio? first experimental results

    International Nuclear Information System (INIS)

    Barillet, S.; Devaux, A.; Simon, O.; Buet, A.; Pradines, C.

    2004-01-01

    Within the Envirhom research program, key advances have been obtained in uranium bioaccumulation and underlying mechanisms understanding in various biological models at the individual level. However, considering different scales of biological effects (from early to delayed ones, from low to high level of organization) is crucial to provide ecologically relevant indicators. Organisms counteract stress induced by pollutant exposure through a wide range of physiological responses being both dose and time dependent. Effects at higher hierarchical levels are always preceded by early changes in biological processes, from subtle biochemical disturbances to impaired physiological functions, increased susceptibility to other stresses, reduced life-span Within this global context, preliminary experiments were carried out on adult zebra fish (Danio rerio), to assess early changes after short-term uranium exposure. Among the subsequent primary subcellular damages oxidative stress and genotoxicity (characterizing both chemo-toxicity and radiotoxicity) are relevant endpoints, thus requiring the knowledge of dose-effects relationships as a first operational approach to provide useful tool in predicting possible effects of U exposure. Zebra fish has been selected due to its small size (facilitating its maintenance) and its extended use in eco-toxicological studies. Moreover, its short life-cycle will allow to carry out chronic exposure experiments (along the whole life-cycle). Four uranium concentrations (0, 20, 100 and 500μg.L -1 ) and five sampling times (0, 0.5, 1, 5 and 10 days) were selected. Catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were measured as oxidative stress bio-markers. DNA damage level was assessed in zebra fish erythrocytes using the comet assay. Uranium bioaccumulation was concurrently studied to understand observed bio-marker responses. Further experiments, dedicated to the assessment of the impact of chronic uranium

  19. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats

    DEFF Research Database (Denmark)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen

    2017-01-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative...... proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33...... proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb...

  20. Reversible antibiotic tolerance induced in Staphylococcus aureus by concurrent drug exposure

    DEFF Research Database (Denmark)

    Haaber, Jakob Krause; Friberg, Cathrine; McCreary, Mark

    2015-01-01

    UNLABELLED: Resistance of Staphylococcus aureus to beta-lactam antibiotics has led to increasing use of the glycopeptide antibiotic vancomycin as a life-saving treatment for major S. aureus infections. Coinfection by an unrelated bacterial species may necessitate concurrent treatment with a second...... antibiotic that targets the coinfecting pathogen. While investigating factors that affect bacterial antibiotic sensitivity, we discovered that susceptibility of S. aureus to vancomycin is reduced by concurrent exposure to colistin, a cationic peptide antimicrobial employed to treat infections by Gram......-negative pathogens. We show that colistin-induced vancomycin tolerance persists only as long as the inducer is present and is accompanied by gene expression changes similar to those resulting from mutations that produce stably inherited reduction of vancomycin sensitivity (vancomycin-intermediate S. aureus [VISA...

  1. Knowledge of vitamin D and perceptions and attitudes toward sunlight among Chinese middle-aged and elderly women: a population survey in Hong Kong

    Directory of Open Access Journals (Sweden)

    Lee Ka-Kui

    2006-09-01

    Full Text Available Abstract Background Physical and biological risk factors for vitamin D inadequacy are known; however, cultural- and population-specific behaviours and attitudes that influence these risk factors, particularly among Asian people, are less well documented. To understand more about prevailing attitudes and behaviour toward sunlight and knowledge of vitamin D among a population at greater risk of impaired vitamin D status, poor bone health and osteoporosis, we conducted a telephone interview survey of 547 middle-aged and elderly Chinese women living in Hong Kong. Methods All telephone interviews were conducted using the Computer Assisted Telephone Technique and target respondents were selected by random sampling. Interviews were conducted in Cantonese and eighteen main questions were asked pertaining to personal characteristics, perceptions, attitudes and behaviour toward sunlight, and knowledge about vitamin D. Results The survey results showed that 62.3% (n = 341 did not like going in the sun and 66.7% of respondents spent an average of 6–10 hours indoors, between 6:30 am and 7:00 pm, during weekdays. However, 58% of people thought that they had enough exposure to sunlight. The majority had heard of vitamin D, but knowledge about the role and sources of vitamin D was low. Among those who knew that sunlight was a source of vitamin D, the majority spent less than 1 h in the sun in the past week (76.4% vs 23.6%, 1 h in the sun in the past week, chi-square p Conclusion The survey revealed considerable ignorance and confusion about the role of sunlight in vitamin D production, and the function and sources of vitamin D. Attitudes and behaviour toward sunlight were largely negative and many took measures to avoid sunlight, particularly among younger (middle-aged women who had good awareness of vitamin D.

  2. Formaldehyde and co-exposure with benzene induce compensation of bone marrow and hematopoietic stem/progenitor cells in BALB/c mice during post-exposure period

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Chenxi [Key Laboratory of Ecological Safety Monitoring and Evaluation, School of Life Sciences, Hunan Normal University, Changsha 410081, Hunan (China); Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, Hubei (China); Chen, Mouying [Key Laboratory of Ecological Safety Monitoring and Evaluation, School of Life Sciences, Hunan Normal University, Changsha 410081, Hunan (China); You, Huihui [Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, Hubei (China); Qiu, Feng [Key Laboratory of Ecological Safety Monitoring and Evaluation, School of Life Sciences, Hunan Normal University, Changsha 410081, Hunan (China); Wen, Huaxiao; Yuan, Junlin [Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, Hubei (China); Xiang, Shuanglin, E-mail: xshlin@hunnu.edu.cn [Key Laboratory of Ecological Safety Monitoring and Evaluation, School of Life Sciences, Hunan Normal University, Changsha 410081, Hunan (China); Yang, Xu, E-mail: yangxu@mail.ccnu.edu.cn [Section of Environmental Biomedicine, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, Hubei (China)

    2017-06-01

    Formaldehyde (FA) is a human leukemogen. Since there is a latency period between initial FA exposure and the development of leukemia, the subsequent impact of FA on hematopoietic stem or progenitor cells (HSCs/HPCs) in post-exposure stage is crucial for a deep understanding of FA-induced hematotoxicity. BALB/c mice were exposed to 3 mg/m{sup 3} FA for 2 weeks, mimicking occupational exposure, and were monitored for another 7 days post-exposure. Meanwhile, we included benzene (BZ) as a positive control, separately and together with FA because co-exposure occurs frequently. After 7-day recovery, colonies of progenitors for CFU-GM and BFU-E, and nucleated bone marrow cells in FA-exposed mice were comparable to controls, although they were significantly reduced during exposure. Levels of reactive oxygen species (ROS) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in CFU-GM and BFU-E from FA-exposed mice were higher than controls, although the increase in 8-OHdG was not significant. Granulocyte-macrophage colony stimulating factor (GM-CSF) level in the FA group was lower than controls, but the expression level for the receptor was not upregulated. It suggests that HSCs/HPCs in FA-exposed mice respond to a small amount of GM-CSF and proliferate rapidly, which may cause a possible risk of expansion of abnormal stem/progenitor cell clones. FA co-exposure with BZ was more potent for promoting CFU-GM formation and inducing ROS in BFU-E and 8-OHdG in CFU-GM during the post-exposure period. The compensation of myeloid progenitors with elevated ROS and 8-OHdG may lead to a risk of transforming normal HSCs/HPCs to leukemic stem/progenitor cells. Thus, co-exposure may pose a greater leukemia risk. - Highlights: • Nucleated bone marrow cell count recovered after 7 days post-FA and/or BZ exposure. • CFU-GM showed an increase in colonies and 8-OHdG after 7 days post-FA + BZ exposure. • Levels of ROS in CFU-GM and BFU-E were increased by FA or FA + BZ during recovery. • Levels of

  3. Formaldehyde and co-exposure with benzene induce compensation of bone marrow and hematopoietic stem/progenitor cells in BALB/c mice during post-exposure period

    International Nuclear Information System (INIS)

    Wei, Chenxi; Chen, Mouying; You, Huihui; Qiu, Feng; Wen, Huaxiao; Yuan, Junlin; Xiang, Shuanglin; Yang, Xu

    2017-01-01

    Formaldehyde (FA) is a human leukemogen. Since there is a latency period between initial FA exposure and the development of leukemia, the subsequent impact of FA on hematopoietic stem or progenitor cells (HSCs/HPCs) in post-exposure stage is crucial for a deep understanding of FA-induced hematotoxicity. BALB/c mice were exposed to 3 mg/m 3 FA for 2 weeks, mimicking occupational exposure, and were monitored for another 7 days post-exposure. Meanwhile, we included benzene (BZ) as a positive control, separately and together with FA because co-exposure occurs frequently. After 7-day recovery, colonies of progenitors for CFU-GM and BFU-E, and nucleated bone marrow cells in FA-exposed mice were comparable to controls, although they were significantly reduced during exposure. Levels of reactive oxygen species (ROS) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in CFU-GM and BFU-E from FA-exposed mice were higher than controls, although the increase in 8-OHdG was not significant. Granulocyte-macrophage colony stimulating factor (GM-CSF) level in the FA group was lower than controls, but the expression level for the receptor was not upregulated. It suggests that HSCs/HPCs in FA-exposed mice respond to a small amount of GM-CSF and proliferate rapidly, which may cause a possible risk of expansion of abnormal stem/progenitor cell clones. FA co-exposure with BZ was more potent for promoting CFU-GM formation and inducing ROS in BFU-E and 8-OHdG in CFU-GM during the post-exposure period. The compensation of myeloid progenitors with elevated ROS and 8-OHdG may lead to a risk of transforming normal HSCs/HPCs to leukemic stem/progenitor cells. Thus, co-exposure may pose a greater leukemia risk. - Highlights: • Nucleated bone marrow cell count recovered after 7 days post-FA and/or BZ exposure. • CFU-GM showed an increase in colonies and 8-OHdG after 7 days post-FA + BZ exposure. • Levels of ROS in CFU-GM and BFU-E were increased by FA or FA + BZ during recovery. • Levels of GM

  4. Evidence for Alteration in Chemical and Physical Properties of Water and Modulation of its Biological Functions by Sunlight Transmitted through Color Ranges of the Visible Spectrum-A Novel Study

    Directory of Open Access Journals (Sweden)

    M. Rajeswara Rao

    2005-08-01

    Full Text Available We investigated the changes in the properties of water when exposed to sunlight for 40 days. We hypothesize and prove that solar irradiation to water entraps electromagnetic radiation as potential energy, which becomes kinetic energy in various systems. It is postulated that photochemically-induced energy transfers, associated with individual spectral emission of visible spectrum of solar light, exert diverse influences on biological systems. Bottles of distilled water, individually wrapped in spectral-colored cellophane were exposed to sunlight and compared to an unwrapped bottle to determine chemical and physical changes as well as modifications of biological properties. Each bottle of water was named according to the color of cellophane paper with letter E (stands for exposed as a prefix with (E-violet, E-indigo, E-blue, E-green, E-yellow, E-orange, and Ered. E-control (without wrap was exposed to polychromatic sunlight. This study addresses two main issues viz., the chemical and physical changes in E-water and its effect on biological activities. Chemical and physical composition analysis using inductively coupled plasma atomic emission spectrometry; physical conductance by a Wheatstone Bridge type conductivity meter; osmolarity by a vapor pressure osmometer; and, salt solubility profile of 10% sodium bicarbonate were determined. Furthermore, testing the effect of E-waters on human lymphocyte proliferation, mosquito larvae hatching and seed germination determined the functional role of solar radiation through specific spectrum/s of visible light on various biological processes. We found that water exposed to visible spectral emissions of sunlight had an altered elemental composition, electrical conductance, osmolarity and salt-solubility, as well as differences in bio-modulatory effects. A gradual increase in leaching of Boron from Eviolet to E-red was noted. E-indigo showed maximal increase in electrical conductance and maximal salt

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  6. PRENATAL ETHANOL EXPOSURE LEADS TO GREATER ETHANOL-INDUCED APPETITIVE REINFORCEMENT

    Science.gov (United States)

    Pautassi, Ricardo M.; Nizhnikov, Michael E.; Spear, Norman E.; Molina, Juan C.

    2012-01-01

    Prenatal ethanol significantly heightens later alcohol consumption, but the mechanisms that underlie this phenomenon are poorly understood. Little is known about the basis of this effect of prenatal ethanol on the sensitivity to ethanol’s reinforcing effects. One possibility is that prenatal ethanol exposure makes subjects more sensitive to the appetitive effects of ethanol or less sensitive to ethanol’s aversive consequences. The present study assessed ethanol-induced second-order conditioned place preference (CPP) and aversion and ethanol-induced conditioned taste aversion (CTA) in infant rats prenatally exposed to ethanol (2.0 g/kg) or vehicle (water) or left untreated. The involvement of the κ opioid receptor system in ethanol-induced CTA was also explored. When place conditioning occurred during the ascending limb of the blood-ethanol curve (Experiment 1), the pups exposed to ethanol in utero exhibited greater CPP than untreated controls, with a shift to the right of the dose-response curve. Conditioning during a later phase of intoxication (30–45 min post-administration; Experiment 2) resulted in place aversion in control pups exposed to vehicle during late gestation but not in pups that were exposed to ethanol in utero. Ethanol induced a reliable and similar CTA (Experiment 3) in the pups treated with vehicle or ethanol during gestation, and CTA was insensitive to κ antagonism. These results suggest that brief exposure to a moderate ethanol dose during late gestation promotes ethanol-mediated reinforcement and alters the expression of conditioned aversion by ethanol. This shift in the motivational reactivity to ethanol may be an underlying basis of the effect of prenatal ethanol on later ethanol acceptance. PMID:22698870

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

    Science.gov (United States)

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

    2015-01-01

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

  8. Prevalence of sun exposure and its associated factors in southern Brazil: a population-based study.

    Science.gov (United States)

    Duquia, Rodrigo Pereira; Menezes, Ana Maria Baptista; Almeida, Hiram Larangeira de; Reichert, Felipe Fossati; Santos, Iná da Silva dos; Haack, Ricardo Lanzetta; Horta, Bernardo Lessa

    2013-01-01

    Sunlight exposure is responsible for a large number of dermatological diseases. We estimated the prevalence of sunlight exposure and its associated factors in adults from southern Brazil in a cross-sectional, population-based study. We investigated a representative sample of individuals aged ≥ 20 years (n=3,136). Sunlight exposure and its associated factors were evaluated in two distinct situations: at leisure time and at work. The time period investigated ranged from December 2004 to March 2005, comprising 120 days of the highest ultraviolet index in the urban area of the city of Pelotas, in southern Brazil. The participants were asked about sunlight exposure for at least 20 minutes between 10 A.M. and 4 P.M. The analysis was stratified by sex, and sunlight exposure was grouped into five categories. Among the 3,136 participants, prevalence of sunlight exposure at the beach was 32.8% (95% CI, 30.3 - 35.2) and 26.3% (95% CI, 24.2 28.3) among men and women, respectively. The prevalence at work was 39.8% (95% CI, 37.2 - 42.4) among men and 10.5% (95% CI, 9.1 - 12.0) among women. Age was inversely associated with sunlight exposure. Family income and achieved schooling were positively associated with sunlight exposure at leisure time and inversely associated with sunglight exposure at work. Self-reported skin color was not associated. Knowledge of any friend or relative who has been affected by skin cancer was positively associated with sunlight exposure among men at work. Despite the media campaigns on the harmful effects of excessive sunlight exposure, we found a high prevalence of sunlight exposure during a period of high ultraviolet index.

  9. Prevalence of sun exposure and its associated factors in southern Brazil: a population-based study*

    Science.gov (United States)

    Duquia, Rodrigo Pereira; Menezes, Ana Maria Baptista; de Almeida, Hiram Larangeira; Reichert, Felipe Fossati; dos Santos, Iná da Silva; Haack, Ricardo Lanzetta; Horta, Bernardo Lessa

    2013-01-01

    BACKGROUND Sunlight exposure is responsible for a large number of dermatological diseases. OBJECTIVE We estimated the prevalence of sunlight exposure and its associated factors in adults from southern Brazil in a cross-sectional, population-based study. METHODS We investigated a representative sample of individuals aged ≥ 20 years (n=3,136). Sunlight exposure and its associated factors were evaluated in two distinct situations: at leisure time and at work. The time period investigated ranged from December 2004 to March 2005, comprising 120 days of the highest ultraviolet index in the urban area of the city of Pelotas, in southern Brazil. The participants were asked about sunlight exposure for at least 20 minutes between 10 A.M. and 4 P.M. The analysis was stratified by sex, and sunlight exposure was grouped into five categories. RESULTS Among the 3,136 participants, prevalence of sunlight exposure at the beach was 32.8% (95% CI, 30.3 - 35.2) and 26.3% (95% CI, 24.2 28.3) among men and women, respectively. The prevalence at work was 39.8% (95% CI, 37.2 - 42.4) among men and 10.5% (95% CI, 9.1 - 12.0) among women. Age was inversely associated with sunlight exposure. Family income and achieved schooling were positively associated with sunlight exposure at leisure time and inversely associated with sunglight exposure at work. Self-reported skin color was not associated. Knowledge of any friend or relative who has been affected by skin cancer was positively associated with sunlight exposure among men at work. CONCLUSION Despite the media campaigns on the harmful effects of excessive sunlight exposure, we found a high prevalence of sunlight exposure during a period of high ultraviolet index. PMID:24068126

  10. Natural sunlight bleaching of the aluminum center in quartz

    International Nuclear Information System (INIS)

    Lin Min; Yin Gongming; Han Kongyan; Bao Jifei; Liu Jingwei; Jia Li

    2007-01-01

    The effect of sunlight bleaching on ESR signals from the aluminum center in quartz is reported for two samples of sand-sized quartz, one from a granite and one from a beach sand. The grains were exposed to direct sunlight for periods of time up to 500 h, with bleaching carried out in four different cities in China that are from 50 to 3600 m above sea level. Each sample bleached to the same residual level, ∼55% for the granite and 80% for the beach sand of the initial value after a 200 Gy dose had been given. After 200 h, the bleaching level reached was independent of the height above sea level

  11. Intensity correlation imaging with sunlight-like source

    Science.gov (United States)

    Wang, Wentao; Tang, Zhiguo; Zheng, Huaibin; Chen, Hui; Yuan, Yuan; Liu, Jinbin; Liu, Yanyan; Xu, Zhuo

    2018-05-01

    We show a method of intensity correlation imaging of targets illuminated by a sunlight-like source both theoretically and experimentally. With a Faraday anomalous dispersion optical filter (FADOF), we have modulated the coherence time of a thermal source up to 0.167 ns. And we carried out measurements of temporal and spatial correlations, respectively, with an intensity interferometer setup. By skillfully using the even Fourier fitting on the very sparse sampling data, the images of targets are successfully reconstructed from the low signal-noise-ratio(SNR) interference pattern by applying an iterative phase retrieval algorithm. The resulting imaging quality is as well as the one obtained by the theoretical fitting. The realization of such a case will bring this technique closer to geostationary satellite imaging illuminated by sunlight.

  12. [Effects of intermittent hypoxic exposure on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha and erythropoietin levels].

    Science.gov (United States)

    Zhang, Cheng-yan; Zhang, Ji-xin; Lü, Xiao-tao; Li, Bao-yu

    2009-10-01

    To investigate the effects of intermittent hypoxic exposure and normoxic convalescence on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha (HIF-1alpha) and erythropoietin (EPO) levels. Rat models of intermittent hypoxic exposure were established, combined with the clinical research on volunteers experiencing the intermittent plateau work. Blood samples for red blood cell (RBC) counts, hemoglobin (Hb) and hematocrit (HCT) were collected, serum HIF-1alpha and EPO levels were measured using enzyme linked immunosorbent assay. RBC counts, Hb concentration and HCT were significantly higher than the normoxic group (P hypoxic exposure can enhance serum hypoxia inducible factor-1 alpha and erythropointin levels and the generation of red blood cells, which leads to an increase in hemoglobin concentration and hematocrit. The results have changed with the hypoxic exposure period prolonged. Normoxic convalescence after intermittent hypoxic exposure can make the related indexes reduced, and contribute to the organism recovery.

  13. Characterization of seizures induced by acute exposure to an organophosphate herbicide, glufosinate-ammonium.

    Science.gov (United States)

    Calas, André-Guilhem; Perche, Olivier; Richard, Olivier; Perche, Astrid; Pâris, Arnaud; Lauga, Fabien; Herzine, Ameziane; Palomo, Jennifer; Ardourel, Marie-Yvonne; Menuet, Arnaud; Mortaud, Stéphane; Pichon, Jacques; Montécot-Dubourg, Céline

    2016-05-04

    Glufosinate-ammonium (GLA), the active component of a widely used herbicide, induces convulsions in rodents and humans. In mouse, intraperitoneal treatment with 75 mg/kg GLA generates repetitive tonic-clonic seizures associated with 100% mortality within 72 h after treatment. In this context, we characterized GLA-induced seizures, their histological consequences and the effectiveness of diazepam treatment. Epileptic discharges on electroencephalographic recordings appeared simultaneously in the hippocampus and the cerebral cortex. Diazepam treatment at 6 h immediately stopped the seizures and prevented animal death. However, intermittent seizures were recorded on electroencephalogram from 6 h after diazepam treatment until 24 h, but had disappeared after 15 days. In our model, neuronal activation (c-Fos immunohistochemistry) was observed 6 h after GLA exposure in the dentate gyrus, CA1, CA3, amygdala, piriform and entorhinal cortices, indicating the activation of the limbic system. In these structures, Fluoro-Jade C and Cresyl violet staining did not show neuronal suffering. However, astroglial activation was clearly observed at 24 h and 15 days after GLA treatment in the amygdala, piriform and entorhinal cortices by PCR quantitative, western blot and immunohistochemistry. Concomitantly, glutamine synthetase mRNA expression (PCR quantitative), protein expression (western blot) and enzymatic activity were upregulated. In conclusion, our study suggests that GLA-induced seizures: (a) involved limbic structures and (b) induced astrocytosis without neuronal degeneration as an evidence of a reactive astrocyte beneficial effect for neuronal protection.

  14. Brain signaling and behavioral responses induced by exposure to (56)Fe-particle radiation

    Science.gov (United States)

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

    2002-01-01

    Previous experiments have demonstrated that exposure to 56Fe-particle irradiation (1.5 Gy, 1 GeV) produced aging-like accelerations in neuronal and behavioral deficits. Astronauts on long-term space flights will be exposed to similar heavy-particle radiations that might have similar deleterious effects on neuronal signaling and cognitive behavior. Therefore, the present study evaluated whether radiation-induced spatial learning and memory behavioral deficits are associated with region-specific brain signaling deficits by measuring signaling molecules previously found to be essential for behavior [pre-synaptic vesicle proteins, synaptobrevin and synaptophysin, and protein kinases, calcium-dependent PRKCs (also known as PKCs) and PRKA (PRKA RIIbeta)]. The results demonstrated a significant radiation-induced increase in reference memory errors. The increases in reference memory errors were significantly negatively correlated with striatal synaptobrevin and frontal cortical synaptophysin expression. Both synaptophysin and synaptobrevin are synaptic vesicle proteins that are important in cognition. Striatal PRKA, a memory signaling molecule, was also significantly negatively correlated with reference memory errors. Overall, our findings suggest that radiation-induced pre-synaptic facilitation may contribute to some previously reported radiation-induced decrease in striatal dopamine release and for the disruption of the central dopaminergic system integrity and dopamine-mediated behavior.

  15. Passive radiative cooling below ambient air temperature under direct sunlight.

    Science.gov (United States)

    Raman, Aaswath P; Anoma, Marc Abou; Zhu, Linxiao; Rephaeli, Eden; Fan, Shanhui

    2014-11-27

    Cooling is a significant end-use of energy globally and a major driver of peak electricity demand. Air conditioning, for example, accounts for nearly fifteen per cent of the primary energy used by buildings in the United States. A passive cooling strategy that cools without any electricity input could therefore have a significant impact on global energy consumption. To achieve cooling one needs to be able to reach and maintain a temperature below that of the ambient air. At night, passive cooling below ambient air temperature has been demonstrated using a technique known as radiative cooling, in which a device exposed to the sky is used to radiate heat to outer space through a transparency window in the atmosphere between 8 and 13 micrometres. Peak cooling demand, however, occurs during the daytime. Daytime radiative cooling to a temperature below ambient of a surface under direct sunlight has not been achieved because sky access during the day results in heating of the radiative cooler by the Sun. Here, we experimentally demonstrate radiative cooling to nearly 5 degrees Celsius below the ambient air temperature under direct sunlight. Using a thermal photonic approach, we introduce an integrated photonic solar reflector and thermal emitter consisting of seven layers of HfO2 and SiO2 that reflects 97 per cent of incident sunlight while emitting strongly and selectively in the atmospheric transparency window. When exposed to direct sunlight exceeding 850 watts per square metre on a rooftop, the photonic radiative cooler cools to 4.9 degrees Celsius below ambient air temperature, and has a cooling power of 40.1 watts per square metre at ambient air temperature. These results demonstrate that a tailored, photonic approach can fundamentally enable new technological possibilities for energy efficiency. Further, the cold darkness of the Universe can be used as a renewable thermodynamic resource, even during the hottest hours of the day.

  16. Repeated restraint stress exposure during early withdrawal accelerates incubation of cue-induced cocaine craving.

    Science.gov (United States)

    Glynn, Ryan M; Rosenkranz, J Amiel; Wolf, Marina E; Caccamise, Aaron; Shroff, Freya; Smith, Alyssa B; Loweth, Jessica A

    2018-01-01

    A major challenge for treating cocaine addiction is the propensity for abstinent users to relapse. Two important triggers for relapse are cues associated with prior drug use and stressful life events. To study their interaction in promoting relapse during abstinence, we used the incubation model of craving and relapse in which cue-induced drug seeking progressively intensifies ('incubates') during withdrawal from extended-access cocaine self-administration. We tested rats for cue-induced cocaine seeking on withdrawal day (WD) 1. Rats were then subjected to repeated restraint stress or control conditions (seven sessions held between WD6 and WD14). All rats were tested again for cue-induced cocaine seeking on WD15, 1 day after the last stress or control session. Although controls showed a time-dependent increase in cue-induced cocaine seeking (incubation), rats exposed to repeated stress in early withdrawal exhibited a more robust increase in seeking behavior between WD1 and WD15. In separate stressed and control rats, equivalent cocaine seeking was observed on WD48. These results indicate that repeated stress in early withdrawal accelerates incubation of cocaine craving, although craving plateaus at the same level were observed in controls. However, 1 month after the WD48 test, rats subjected to repeated stress in early withdrawal showed enhanced cue-induced cocaine seeking following acute (24 hours) food deprivation stress. Together, these data indicate that chronic stress exposure enhances the initial rate of incubation of craving during early withdrawal, resulting in increased vulnerability to cue-induced relapse during this period, and may lead to a persistent increase in vulnerability to the relapse-promoting effects of stress. © 2016 Society for the Study of Addiction.

  17. Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

    International Nuclear Information System (INIS)

    Barillet, Sabrina; Adam-Guillermin, Christelle; Palluel, Olivier; Porcher, Jean-Marc; Devaux, Alain

    2011-01-01

    Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: → Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 μg/L. → Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. → DNA damage is induced in red blood cells after 20 d of exposure to 500 μg DU/L. → The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

  18. Prepubertal Exposure to Genistein Alleviates Di-(2-ethylhexyl Phthalate Induced Testicular Oxidative Stress in Adult Rats

    Directory of Open Access Journals (Sweden)

    Lian-Dong Zhang

    2014-01-01

    Full Text Available Di-(2-ethylhexyl phthalate (DEHP is the most widely used plastizer in the world and can suppress testosterone production via activation of oxidative stress. Genistein (GEN is one of the isoflavones ingredients exhibiting weak estrogenic and potentially antioxidative effects. However, study on reproductive effects following prepubertal multiple endocrine disrupters exposure has been lacking. In this study, DEHP and GEN were administrated to prepubertal male Sprague-Dawley rats by gavage from postnatal day 22 (PND22 to PND35 with vehicle control, GEN at 50 mg/kg body weight (bw/day (G, DEHP at 50, 150, 450 mg/kg bw/day (D50, D150, D450 and their mixture (G + D50, G + D150, G + D450. On PND90, general morphometry (body weight, AGD, organ weight, and organ coefficient, testicular redox state, and testicular histology were studied. Our results indicated that DEHP could significantly decrease sex organs weight, organ coefficient, and testicular antioxidative ability, which largely depended on the dose of DEHP. However, coadministration of GEN could partially alleviate DEHP-induced reproductive injuries via enhancement of testicular antioxidative enzymes activities, which indicates that GEN has protective effects on DEHP-induced male reproductive system damage after prepubertal exposure and GEN may have promising future in its curative antioxidative role for reproductive disorders caused by other environmental endocrine disruptors.

  19. Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, Sabrina, E-mail: sabrina.barillet@free.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Palluel, Olivier, E-mail: olivier.palluel@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Porcher, Jean-Marc, E-mail: jean-marc.porcher@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Devaux, Alain, E-mail: alain.devaux@entpe.f [Universite de Lyon, INRA, EFPA-SA, Environmental Science Laboratory (LSE), ENTPE, 69518 Vaulx en Velin cedex (France)

    2011-02-15

    Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 {mu}g/L. Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. DNA damage is induced in red blood cells after 20 d of exposure to 500 {mu}g DU/L. The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

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

    Science.gov (United States)

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

    2013-10-01

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

  1. Oral Exposure to Atrazine Induces Oxidative Stress and Calcium Homeostasis Disruption in Spleen of Mice

    Directory of Open Access Journals (Sweden)

    Shuying Gao

    2016-01-01

    Full Text Available The widely used herbicide atrazine (ATR can cause many adverse effects including immunotoxicity, but the underlying mechanisms are not fully understood. The current study investigated the role of oxidative stress and calcium homeostasis in ATR-induced immunotoxicity in mice. ATR at doses of 0, 100, 200, or 400 mg/kg body weight was administered to Balb/c mice daily for 21 days by oral gavage. The studies performed 24 hr after the final exposure showed that ATR could induce the generation of reactive oxygen species in the spleen of the mice, increase the level of advanced oxidation protein product (AOPP in the host serum, and cause the depletion of reduced glutathione in the serum, each in a dose-related manner. In addition, DNA damage was observed in isolated splenocytes as evidenced by increase in DNA comet tail formation. ATR exposure also caused increases in intracellular Ca2+ within splenocytes. Moreover, ATR treatment led to increased expression of genes for some antioxidant enzymes, such as HO-1 and Gpx1, as well as increased expression of NF-κB and Ref-1 proteins in the spleen. In conclusion, it appears that oxidative stress and disruptions in calcium homeostasis might play an important role in the induction of immunotoxicity in mice by ATR.

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

    Science.gov (United States)

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

    2015-01-01

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

  3. Effect of vitamin E on lead exposure-induced learning and memory impairment in rats.

    Science.gov (United States)

    Khodamoradi, Nasrin; Komaki, Alireza; Salehi, Iraj; Shahidi, Siamak; Sarihi, Abdolrahman

    2015-05-15

    Chronic lead (Pb(2+)) exposure has been associated with learning and memory impairments, whereas vitamin E improves cognitive deficits. In this study, using a passive avoidance learning model in rats, we investigated the effects of vitamin E on Pb(2+) exposure-induced learning and memory impairments in rats. In the present study, 56 Wistar male rats (weighting 230-250g) were divided into eight groups (n=7). The Pb(2+) exposure involved gavages of lead acetate solution using three different doses (0.05%, 0.1%, and 0.2%) and the vitamin E consisted of three different doses (10, 25, 50μg/rat) for 30days. After the 30-day period, the rats were tested using a passive avoidance task (acquisition test). In a retrieval test conducted 48h after the training, step through latency (STL) and time in the dark compartment (TDC) were recorded. The statistical analysis of data was performed using ANOVA followed by Tukey's post hoc analysis. In all cases, differences were considered significant if plearning and the TDC, whereas it decreased the STL in the passive avoidance test. Administration of vitamin E ameliorated the effects of Pb(2+) on animal behavior in the passive avoidance learning and memory task. Our results indicate that impairments of learning and memory in Pb(2+)-exposed rats are dose dependent and can be inhibited by antioxidants such as vitamin E. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2009-11-01

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

  5. DNA damage and oxidative stress induced by imidacloprid exposure in the earthworm Eisenia fetida.

    Science.gov (United States)

    Wang, Juan; Wang, Jinhua; Wang, Guangchi; Zhu, Lusheng; Wang, Jun

    2016-02-01

    To investigate the soil ecological effect of imidacloprid, earthworm Eisenia fetida was exposed to various concentrations of imidacloprid (0.10, 0.50, and 1.00 mg kg(-1) soil) respectively after 7, 14, 21, and 28 d. The effect of imidacloprid on reactive oxygen species (ROS) generation, antioxidant enzymes activity [superoxide dismutase (SOD) and catalase (CAT), glutathione S-transferase enzyme (GST)], malondialdehyde (MDA) content and DNA damage of the E. fetida was investigated. Significant increase of the ROS level was observed. The SOD and GST activity were significantly induced at most exposure intervals. CAT activity was inhibited and reflected a dose-dependent relationship on days 7, 14 and 21. High MDA levels were observed and the olive tail moment (OTM) as well as the percentage of DNA in the comet tail (tail DNA%) in comet assay declined with increasing concentrations and exposure time after 7 d. Our results suggested that the sub-chronic exposure of imidacloprid caused DNA damage and lipid peroxidation (LPO) leading to antioxidant responses in earthworm E. fetida. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Water accelerated transformation of d-limonene induced by ultraviolet irradiation and air exposure.

    Science.gov (United States)

    Li, Li Jun; Hong, Peng; Jiang, Ze Dong; Yang, Yuan Fan; Du, Xi Ping; Sun, Hao; Wu, Li Ming; Ni, Hui; Chen, Feng

    2018-01-15

    d-Limonene is a fragrant chemical that widely exists in aromatic products. Isotopic labelling of water molecules plus GC-MS and GC-PCI-Q-TOF analyses were used to investigate the influence of water molecules on chemical transformation of d-limonene induced by UV irradiation and air exposure. The results showed that the synergistic effect of UV irradiation, air exposure and water presence could facilitate d-limonene transformation into the limonene oxides: p-mentha-2,8-dienols, hydroperoxides, carveols, l-carvone and carvone oxide. UV irradiation, air exposure, or water alone, however, caused negligible d-limonene transformation. With the aid of isotopic labelling of water and oxygen molecules, it was found that water molecules were split into hydrogen radicals and hydroxyl radicals, and the hydrogen radicals, in particular, promoted the transformation reactions. This study has elucidated the mechanism and factors that influence the transformation of d-limonene, which will benefit industries involved in production and storage of d-limonene-containing products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Light-induced Variation in Phenolic Compounds in Cabernet Sauvignon Grapes (Vitis vinifera L.) Involves Extensive Transcriptome Reprogramming of Biosynthetic Enzymes, Transcription Factors, and Phytohormonal Regulators.

    Science.gov (United States)

    Sun, Run-Ze; Cheng, Guo; Li, Qiang; He, Yan-Nan; Wang, Yu; Lan, Yi-Bin; Li, Si-Yu; Zhu, Yan-Rong; Song, Wen-Feng; Zhang, Xue; Cui, Xiao-Di; Chen, Wu; Wang, Jun

    2017-01-01

    Light environments have long been known to influence grape ( Vitis vinifera L.) berry development and biosynthesis of phenolic compounds, and ultimately affect wine quality. Here, the accumulation and compositional changes of hydroxycinnamic acids (HCAs) and flavonoids, as well as global gene expression were analyzed in Cabernet Sauvignon grape berries under sunlight exposure treatments at different phenological stages. Sunlight exposure did not consistently affect the accumulation of berry skin flavan-3-ol or anthocyanin among different seasons due to climatic variations, but increased HCA content significantly at véraison and harvest, and enhanced flavonol accumulation dramatically with its timing and severity degree trend. As in sunlight exposed berries, a highly significant correlation was observed between the expression of genes coding phenylalanine ammonia-lyase, 4-coumarate: CoA ligase, flavanone 3-hydroxylase and flavonol synthase family members and corresponding metabolite accumulation in the phenolic biosynthesis pathway, which may positively or negatively be regulated by MYB, bHLH, WRKY, AP2/EREBP, C2C2, NAC, and C2H2 transcription factors (TFs). Furthermore, some candidate genes required for auxin, ethylene and abscisic acid signal transductions were also identified which are probably involved in berry development and flavonoid biosynthesis in response to enhanced sunlight irradiation. Taken together, this study provides a valuable overview of the light-induced phenolic metabolism and transcriptome changes, especially the dynamic responses of TFs and signaling components of phytohormones, and contributes to the further understanding of sunlight-responsive phenolic biosynthesis regulation in grape berries.

  8. Light-induced Variation in Phenolic Compounds in Cabernet Sauvignon Grapes (Vitis vinifera L.) Involves Extensive Transcriptome Reprogramming of Biosynthetic Enzymes, Transcription Factors, and Phytohormonal Regulators

    Science.gov (United States)

    Sun, Run-Ze; Cheng, Guo; Li, Qiang; He, Yan-Nan; Wang, Yu; Lan, Yi-Bin; Li, Si-Yu; Zhu, Yan-Rong; Song, Wen-Feng; Zhang, Xue; Cui, Xiao-Di; Chen, Wu; Wang, Jun

    2017-01-01

    Light environments have long been known to influence grape (Vitis vinifera L.) berry development and biosynthesis of phenolic compounds, and ultimately affect wine quality. Here, the accumulation and compositional changes of hydroxycinnamic acids (HCAs) and flavonoids, as well as global gene expression were analyzed in Cabernet Sauvignon grape berries under sunlight exposure treatments at different phenological stages. Sunlight exposure did not consistently affect the accumulation of berry skin flavan-3-ol or anthocyanin among different seasons due to climatic variations, but increased HCA content significantly at véraison and harvest, and enhanced flavonol accumulation dramatically with its timing and severity degree trend. As in sunlight exposed berries, a highly significant correlation was observed between the expression of genes coding phenylalanine ammonia-lyase, 4-coumarate: CoA ligase, flavanone 3-hydroxylase and flavonol synthase family members and corresponding metabolite accumulation in the phenolic biosynthesis pathway, which may positively or negatively be regulated by MYB, bHLH, WRKY, AP2/EREBP, C2C2, NAC, and C2H2 transcription factors (TFs). Furthermore, some candidate genes required for auxin, ethylene and abscisic acid signal transductions were also identified which are probably involved in berry development and flavonoid biosynthesis in response to enhanced sunlight irradiation. Taken together, this study provides a valuable overview of the light-induced phenolic metabolism and transcriptome changes, especially the dynamic responses of TFs and signaling components of phytohormones, and contributes to the further understanding of sunlight-responsive phenolic biosynthesis regulation in grape berries. PMID:28469625

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

    Science.gov (United States)

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

    2017-10-01

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

  10. Exposure to tributyltin induces endoplasmic reticulum stress and the unfolded protein response in zebrafish.

    Science.gov (United States)

    Komoike, Yuta; Matsuoka, Masato

    2013-10-15

    Tributyltin (TBT) is a major marine contaminant and causes endocrine disruption, hepatotoxicity, immunotoxicity, and neurotoxicity. However, the molecular mechanisms underlying the toxicity of TBT have not been fully elucidated. We examined whether exposure to TBT induces the endoplasmic reticulum (ER) stress response in zebrafish, a model organism. Zebrafish-derived BRF41 fibroblast cells were exposed to 0.5 or 1 μM TBT for 0.5-16 h and subsequently lysed and immunoblotted to detect ER stress-related proteins. Zebrafish embryos, grown until 32 h post fertilization (hpf), were exposed to 1 μM TBT for 16 h and used in whole mount in situ hybridization and immunohistochemistry to visualize the expression of ER chaperones and an ER stress-related apoptosis factor. Exposure of the BRF41 cells to TBT caused phosphorylation of the zebrafish homolog of protein kinase RNA-activated-like ER kinase (PERK), eukaryotic translation initiation factor 2 alpha (eIF2α), and inositol-requiring enzyme 1 (IRE1), characteristic splicing of X-box binding protein 1 (XBP1) mRNA, and enhanced expression of activating transcription factor 4 (ATF4) protein. In TBT-exposed zebrafish embryos, ectopic expression of the gene encoding zebrafish homolog of the 78 kDa glucose-regulating protein (GRP78) and gene encoding CCAAT/enhancer-binding protein homologous protein (CHOP) was detected in the precursors of the neuromast, which is a sensory organ for detecting water flow and vibration. Our in vitro and in vivo studies revealed that exposure of zebrafish to TBT induces the ER stress response via activation of both the PERK-eIF2α and IRE1-XBP1 pathways of the unfolded protein response (UPR) in an organ-specific manner. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Cold exposure rapidly induces virtual saturation of brown adipose tissue nuclear T3 receptors

    International Nuclear Information System (INIS)

    Bianco, A.C.; Silva, J.E.

    1988-01-01

    Cold exposure induces a rapid increase in uncoupling protein (UCP) concentration in the brown adipose tissue (BAT) of euthyroid, but not hypothyroid, rats. To normalize this response with exogenous 3,5,3'-triiodothyronine (T 3 ), it is necessary to cause systemic hyperthyroidism. In contrast, the same result can be obtained with just replacement doses of thyroxine (T 4 ) and, in euthyroid rats, the normal response of UCP to cold occurs without hyperthyroid plasma T 3 levels. Consequently, the authors explored the possibility that the cold-induced activation of the type II 5'-deiodinase resulted in high levels of nuclear T 3 receptor occupancy in euthyroid rats. Studies were performed with pulse injections of tracer T 3 or T 4 in rats exposed to 4 degree C for different lengths of time (1 h-3 wk). Within 4 h of cold exposure, they observed a significant increase in the nuclear [ 125 I]T 3 derived from the tracer [ 125 I]T 4 injections (T 3 [T 4 ]) and a significant reduction in the nuclear [ 125 I]T 3 derived from [ 125 I]T 3 injections (T 3 [T 3 ]). The number of BAT nuclear T 3 receptors did not increase for up to 3 wk of observation at 4 degree C. The mass of nuclear-bound T 3 was calculated from the nuclear tracer [ 125 I]T 3 [T 3 ] and [ 125 I]T 3 [T 4 ] at equilibrium and the specific activity of serum T 3 and T 4 , respectively. By 4 h after the initiation of the cold exposure, the receptors were >95% occupied and remained so for the 3 weeks of observation. They conclude that the simultaneous activation of the deiodinase with adrenergic BAT stimulation serves the purpose of nearly saturating the nuclear T 3 receptors. This makes possible the realization of the full thermogenic potential of the tissue without causing systemic hyperthyroidism

  12. Subchronic Arsenic Exposure Induces Anxiety-Like Behaviors in Normal Mice and Enhances Depression-Like Behaviors in the Chemically Induced Mouse Model of Depression

    Directory of Open Access Journals (Sweden)

    Chia-Yu Chang

    2015-01-01

    Full Text Available Accumulating evidence implicates that subchronic arsenic exposure causes cerebral neurodegeneration leading to behavioral disturbances relevant to psychiatric disorders. However, there is still little information regarding the influence of subchronic exposure to arsenic-contaminated drinking water on mood disorders and its underlying mechanisms in the cerebral prefrontal cortex. The aim of this study is to assess the effects of subchronic arsenic exposure (10 mg/LAs2O3 in drinking water on the anxiety- and depression-like behaviors in normal mice and in the chemically induced mouse model of depression by reserpine pretreatment. Our findings demonstrated that 4 weeks of arsenic exposure enhance anxiety-like behaviors on elevated plus maze (EPM and open field test (OFT in normal mice, and 8 weeks of arsenic exposure augment depression-like behaviors on tail suspension test (TST and forced swimming test (FST in the reserpine pretreated mice. In summary, in this present study, we demonstrated that subchronic arsenic exposure induces only the anxiety-like behaviors in normal mice and enhances the depression-like behaviors in the reserpine induced mouse model of depression, in which the cerebral prefrontal cortex BDNF-TrkB signaling pathway is involved. We also found that eight weeks of subchronic arsenic exposure are needed to enhance the depression-like behaviors in the mouse model of depression. These findings imply that arsenic could be an enhancer of depressive symptoms for those patients who already had the attribute of depression.

  13. Acute Acrolein Exposure Induces Impairment of Vocal Fold Epithelial Barrier Function.

    Directory of Open Access Journals (Sweden)

    Xinxin Liu

    Full Text Available Acrolein is a ubiquitous pollutant abundant in cigarette smoke, mobile exhaust, and industrial waste. There is limited literature on the effects of acrolein on vocal fold tissue, although there are clinical reports of voice changes after pollutant exposures. Vocal folds are responsible for voice production. The overall objective of this study was to investigate the effects of acrolein exposure on viable, excised vocal fold epithelial tissue and to characterize the mechanism underlying acrolein toxicity. Vocal fold epithelia were studied because they form the outermost layer of the vocal folds and are a primary recipient of inhaled pollutants. Porcine vocal fold epithelia were exposed to 0, 50, 100, 500, 900 or 1300 μM of acrolein for 3 hours; the metabolic activity, epithelial resistance, epithelial permeability, tight junction protein (occludin and claudin 3 expression, cell membrane integrity and lipid peroxidation were investigated. The data demonstrated that acrolein exposure at 500 μM significantly reduced vocal fold epithelial metabolic activity by 27.2% (p≤0.001. Incubation with 100 μM acrolein caused a marked increase in epithelial permeability by 130.5% (p<0.05 and a reduction in transepithelial electrical resistance (TEER by 180.0% (p<0.001. While the expression of tight junctional protein did not change in acrolein-treated samples, the cell membrane integrity was significantly damaged with a 45.6% increase of lipid peroxidation as compared to controls (p<0.05. Taken together, these data provide evidence that acute acrolein exposure impairs vocal fold epithelial barrier integrity. Lipid peroxidation-induced cell membrane damage may play an important role in reducing the barrier function of the epithelium.

  14. Perturbations in different forms of cost/benefit decision making induced by repeated amphetamine exposure.

    Science.gov (United States)

    Floresco, Stan B; Whelan, Jennifer M

    2009-08-01

    Psychostimulant abuse has been linked to impairments in cost-benefit decision making. We assessed the effects of repeated amphetamine (AMPH) treatment in rodents on two distinct forms of decision making. Separate groups of rats were trained for 26 days on either a probabilistic (risk) or effort-discounting task, each consisting of four discrete blocks of ten choice trials. One lever always delivered a smaller reward (one or two pellets), whereas another lever delivered a four-pellet reward. For risk-discounting, the probability of receiving the larger reward decreased across trial blocks (100-12.5%), whereas on the effort task, four pellets could be obtained after a ratio of presses that increased across blocks (2-20). After training, rats received 15 saline or AMPH injections (escalating from 1 to 5 mg/kg) and were then retested during acute and long-term withdrawal. Repeated AMPH administration increased risky choice 2-3 weeks after drug exposure, whereas these treatments did not alter effort-based decision making in a separate group of animals. However, prior AMPH exposure sensitized the effects of acute AMPH on both forms of decision making, whereby lower doses were effective at inducing "risky" and "lazy" patterns of choice. Repeated AMPH exposure leads to relatively long-lasting increases in risky choice, as well as sensitization to the effects of acute AMPH on different forms of cost/benefit decision making. These findings suggest that maladaptive decision-making processes exhibited by psychostimulant abusers may be caused in part by repeated drug exposure.

  15. Intestinal exposure to PCB 153 induces inflammation via the ATM/NEMO pathway.

    Science.gov (United States)

    Phillips, Matthew C; Dheer, Rishu; Santaolalla, Rebeca; Davies, Julie M; Burgueño, Juan; Lang, Jessica K; Toborek, Michal; Abreu, Maria T

    2018-01-15

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants that adversely affect human health. PCBs bio-accumulate in organisms important for human consumption. PCBs accumulation in the body leads to activation of the transcription factor NF-κB, a major driver of inflammation. Despite dietary exposure being one of the main routes of exposure to PCBs, the gut has been widely ignored when studying the effects of PCBs. We investigated the effects of PCB 153 on the intestine and addressed whether PCB 153 affected intestinal permeability or inflammation and the mechanism by which this occurred. Mice were orally exposed to PCB 153 and gut permeability was assessed. Intestinal epithelial cells (IECs) were collected and evaluated for evidence of genotoxicity and inflammation. A human IEC line (SW480) was used to examine the direct effects of PCB 153 on epithelial function. NF-кB activation was measured using a reporter assay, DNA damage was assessed, and cytokine expression was ascertained with real-time PCR. Mice orally exposed to PCB 153 had an increase in intestinal permeability and inflammatory cytokine expression in their IECs; inhibition of NF-кB ameliorated both these effects. This inflammation was associated with genotoxic damage and NF-кB activation. Exposure of SW480 cells to PCB 153 led to similar effects as seen in vivo. We found that activation of the ATM/NEMO pathway by genotoxic stress was upstream of NF-kB activation. These results demonstrate that oral exposure to PCB 153 is genotoxic to IECs and induces downstream inflammation and barrier dysfunction in the intestinal epithelium. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  17. Prioritizing Roads Safety Based on the Quasi-Induced Exposure Method and Utilization of the Analytical Hierarchy Process

    Directory of Open Access Journals (Sweden)

    Sajad rezaei

    2014-06-01

    Full Text Available Safety analysis of the roads through the accident rates which is one of the widely used tools has been resulted from the direct exposure method which is based on the ratio of the vehicle-kilometers traveled and vehicle-travel time. However, due to some fundamental flaws in its theories and difficulties in gaining access to the data required such as traffic volume, distance and duration of the trip, and various problems in determining the exposure in a specific time, place, and individual categories, there is a need for an algorithm for prioritizing the road safety so that with a new exposure method, the problems of the previous approaches would be resolved. In this way, an efficient application may lead to have more realistic comparisons and the new method would be applicable to a wider range of time, place, and individual categories. Therefore, an algorithm was introduced to prioritize the safety of roads using the quasi-induced exposure method and utilizing the analytical hierarchy process. For this research, 11 provinces of Iran were chosen as case study locations. A rural accidents database was created for these provinces, the validity of quasi-induced exposure method for Iran’s accidents database was explored, and the involvement ratio for different characteristics of the drivers and the vehicles was measured. Results showed that the quasi-induced exposure method was valid in determining the real exposure in the provinces under study. Results also showed a significant difference in the prioritization based on the new and traditional approaches. This difference mostly would stem from the perspective of the quasi-induced exposure method in determining the exposure, opinion of experts, and the quantity of accidents data. Overall, the results for this research showed that prioritization based on the new approach is more comprehensive and reliable compared to the prioritization in the traditional approach which is dependent on various

  18. Photoelectrochemical-type sunlight photodetector based on MoS2/graphene heterostructure

    International Nuclear Information System (INIS)

    Huang, Zongyu; Han, Weijia; Chander, D Sathish; Qi, Xiang; Zhang, Han; Tang, Hongli; Ren, Long

    2015-01-01

    We have fabricated a novel sunlight photo-detector based on a MoS 2 /graphene heterostructure. The MoS 2 /graphene heterostructure was prepared by a facile hydrothermal method along with a subsequent annealing process followed by a substrate-induced high selective nucleation and growth mechanism. The microstructures and morphologies of the two-dimensional MoS 2 /graphene heterostructure can be experimentally confirmed by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and a UV–vis absorption spectrometer. Photoresponse investigations performed by a photoelectrochemical (PEC) measurement system indicate that the synthesized MoS 2 /graphene heterostructure shows superior photoresponse activities under the illumination of sunlight in contrast with bare MoS 2 and graphene. The improved photoresponsivity can be attributed to the enhanced light absorption, strong light–matter interaction and the extremely efficient charge separation of the heterostructure. The structure and performances of the MoS 2 /graphene heterostructure suggest promising applications in the field of photonics and optoelectronics. (paper)

  19. Polyuria-associated hydronephrosis induced by xenobiotic chemical exposure in mice.

    Science.gov (United States)

    Yoshioka, Wataru; Kawaguchi, Tatsuya; Nishimura, Noriko; Akagi, Toshiya; Fujisawa, Nozomi; Yanagisawa, Hiroyuki; Matsumura, Fumio; Tohyama, Chiharu

    2016-10-01

    Hydronephrosis is a commonly found disease state characterized by the dilation of renal calices and pelvis, resulting in the loss of kidney function in the severest cases. A generally accepted etiology of hydronephrosis involves the obstruction of urine flow along the urinary tract. In the recent years, we have developed a mouse model of hydronephrosis induced by lactational exposure to dioxin and demonstrated a lack of anatomical obstruction in this model. We also showed that prostaglandin E 2 synthesis system plays a critical role in the onset of hydronephrosis. In the present study, we found that neonatal hydronephrosis was not likely to be associated with functional obstruction (impaired peristalsis) but was found to be associated with polyuria and low urine osmolality with the downregulation of proteins involved in the urine concentrating process. The administration of an antidiuretic hormone analog to the dioxin-exposed pups not only suppressed the increased urine output but also decreased the incidence and severity of hydronephrosis. In contrast to the case in pups, administration of dioxin to adult mice failed to induce polyuria and upregulation of prostaglandin E 2 synthesis system, and the adult mice were resistant to develop hydronephrosis. These findings suggest the possibility that polyuria could induce hydronephrosis in the absence of anatomical or functional obstruction of the ureter. It is concluded that the present animal model provides a unique example of polyuria-associated type of hydronephrosis, suggesting a need to redefine this disease state. Copyright © 2016 the American Physiological Society.

  20. A Transient Exposure to Symbiosis-Competent Bacteria Induces Light Organ Morphogenesis in the Host Squid.

    Science.gov (United States)

    Doino, J A; McFall-Ngai, M J

    1995-12-01

    Recent studies of the symbiotic association between the Hawaiian sepiolid squid Euprymna scolopes and the luminous bacterium Vibrio fischeri have shown that colonization of juvenile squid with symbiosis-competent bacteria induces morphogenetic changes of the light organ. These changes occur over a 4-day period and include cell death and tissue regression of the external ciliated epithelium. In the absence of bacterial colonization, morphogenesis does not occur. To determine whether the bacteria must be present throughout the morphogenetic process, we used the antibiotic chloramphenicol to clear the light organ of bacteria at various times during the initial colonization. We provide evidence in this study that a transient, 12-hour exposure to symbiosis-competent bacteria is necessary and sufficient to induce tissue regression in the light organ over the next several days. Further, we show that successful entrance into the light organ is necessary to induce morphogenesis, suggesting that induction results from bacterial interaction with internal crypt cells and not with the external ciliated epithelium. Finally, no difference in development was observed when the light organ was colonized by a mutant strain of V. fischeri that did not produce autoinducer, a potential light organ morphogen.

  1. Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

    International Nuclear Information System (INIS)

    Woźny, Maciej; Lewczuk, Bogdan; Ziółkowska, Natalia; Gomułka, Piotr; Dobosz, Stefan; Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł

    2016-01-01

    To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg −1 ) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg −1 ) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

  2. Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

    Energy Technology Data Exchange (ETDEWEB)

    Woźny, Maciej, E-mail: maciej.wozny@uwm.edu.pl [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland); Lewczuk, Bogdan; Ziółkowska, Natalia [Department of Histology and Embryology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 13, 10-713 Olsztyn (Poland); Gomułka, Piotr [Department of Ichthyology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 5, 10-719 Olsztyn (Poland); Dobosz, Stefan [Department of the Salmonid Research in Rutki, Inland Fisheries Institute in Olsztyn, Rutki, 83-330 Żukowo (Poland); Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland)

    2016-12-15

    To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg{sup −1}) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg{sup −1}) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

  3. Severe malformations of eelpout (Zoarces viviparus) fry are induced by maternal estrogenic exposure during early embryogenesis

    DEFF Research Database (Denmark)

    Morthorst, Jane Ebsen; Korsgaard, Bodil; Bjerregaard, Poul

    2016-01-01

    Pregnant eelpout were exposed via the water to known endocrine disrupting compounds (EDCs) to clarify if EDCs could be causing the increased eelpout fry malformation frequencies observed in coastal areas receiving high anthropogenic input. The presence of a teratogenic window for estrogen...... induced by EE2 (5.7 and 17.8 ng/L) but not by 4-t-OP and pyrene. A critical period for estrogen-induced fry malformations was identified and closed between 14 and 22 days post fertilization (dpf). Exposure to 17β-estradiol (E2) between 0 and 14 dpf caused severe malformations and severity increased...... the closer exposure start was to fertilization, whereas malformations were absent by exposure starting later than 14 dpf. Data on ovarian fluid volume and larval length supported the suggested teratogenic window. Larval mortality also increased when exposure started right after fertilization....

  4. Does exposure to UV radiation induce a shift to a Th-2-like immune reaction?

    International Nuclear Information System (INIS)

    Ullrich, S.E.

    1996-01-01

    In addition to being the primary cause of skin cancer, UV radiation is immune suppressive and there appears to be a link between the ability of UV to suppress the immune response and induce skin cancer. Cytokines made by UV-irradiated keratinocytes play an essential role in activating immune suppression. In particular, we have found that keratinocyte-derived interleukin (IL)-10 is responsible for the systemic impairment of antigen presenting cell function and the UV-induced suppression of delayed-type hypersenstivity (DTH). Antigen presentation by splenic adherent cells isolated from UV-irradiated mice to T helper-1 type T (Th1) cells is suppressed, whereas antigen presentation to T helper-2 type T (Th2) cells is enhanced. The enhanced antigen presentation to Th2 cells and the impaired presentation to Th1 cells can be reversed in vivo by injecting the UV-irradiated mice with monoclonal anti-IL-10 antibody. Furthermore, immune suppression can be transferred from UV-irradiated mice to normal recipients by adoptive transfer of T cells. Injecting the recipient mice with anti-IL-4 or anti-IL-10 prevents the transfer of immune suppression, suggesting the suppressor cells are Th2 cells. In addition, injecting UV-irradiated mice with IL-12, a cytokine that has been shown to be the primary inducer of Th1 cells, and one that prevents the differentiation of Th2 cells in vivo, reverses UV-induced immune suppression. These findings support the hypothesis that UV exposure activates IL-10 secretion, which depresses the function of Th1 cells, while enhancing the activity of Th2 cells. (Author)

  5. Altered Microbiota Contributes to Reduced Diet-Induced Obesity upon Cold Exposure

    DEFF Research Database (Denmark)

    Ziętak, Marika; Kovatcheva-Datchary, Petia; Markiewicz, Lidia H

    2016-01-01

    Maintenance of body temperature in cold-exposed animals requires induction of thermogenesis and management of fuel. Here, we demonstrated that reducing ambient temperature attenuated diet-induced obesity (DIO), which was associated with increased iBAT thermogenesis and a plasma bile acid profile...... similar to that of germ-free mice. We observed a marked shift in the microbiome composition at the phylum and family levels within 1 day of acute cold exposure and after 4 weeks at 12°C. Gut microbiota was characterized by increased levels of Adlercreutzia, Mogibacteriaceae, Ruminococcaceae......, and Desulfovibrio and reduced levels of Bacilli, Erysipelotrichaceae, and the genus rc4-4. These genera have been associated with leanness and obesity, respectively. Germ-free mice fed a high-fat diet at room temperature gained less adiposity and improved glucose tolerance when transplanted with caecal microbiota...

  6. Virtual nature environment with nature sound exposure induce stress recovery by enhanced parasympathetic activity

    DEFF Research Database (Denmark)

    Annerstedt, Matilda; Jönsson, Peter; Wallergård, Mattias

    2013-01-01

    . The group that recovered in virtual nature without sound and the control group displayed no particular autonomic activation or deactivation. The results demonstrate a potential mechanistic link between nature, the sounds of nature, and stress recovery, and suggest the potential importance of virtual reality......Experimental research on stress recovery in natural environments is limited, as is study of the effect of sounds of nature. After inducing stress by means of a virtual stress test, we explored physiological recovery in two different virtual natural environments (with and without exposure to sounds...... of nature) and in one control condition. Cardiovascular data and saliva cortisol were collected. Repeated ANOVA measurements indicated parasympathetic activation in the group subjected to sounds of nature in a virtual natural environment, suggesting enhanced stress recovery may occur in such surroundings...

  7. Exposures to Conditioned Flavours with Different Hedonic Values Induce Contrasted Behavioural and Brain Responses in Pigs

    Science.gov (United States)

    Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

    2012-01-01

    This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (FGlu), lithium chloride (FLiCl), or saline (control treatment, FNaCl). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three 18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the FLiCl than the FNaCl or FGlu meals. During the two-choice tests performed one and five weeks later, the FNaCl and FGlu foods were significantly preferred over the FLICl food even in the absence of i.d. infusions. Surprisingly, the FNaCl food was also preferred over the FGlu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake. PMID:22685528

  8. Exposure to Alumina Nanoparticles in Female Mice During Pregnancy Induces Neurodevelopmental Toxicity in the Offspring.

    Science.gov (United States)

    Zhang, Qinli; Ding, Yong; He, Kaihong; Li, Huan; Gao, Fuping; Moehling, Taylor J; Wu, Xiaohong; Duncan, Jeremy; Niu, Qiao

    2018-01-01

    Alumina nanoparticles (AlNP) have been shown to accumulate in organs and penetrate biological barriers which lead to toxic effects in many organ systems. However, it is not known whether AlNP exposure to female mice during pregnancy can affect the development of the central nervous system or induce neurodevelopmental toxicity in the offspring. The present study aims to examine the effect of AlNP on neurodevelopment and associated underlying mechanism. ICR strain adult female mice were randomly divided into four groups, which were treated with normal saline (control), 10 μm particle size of alumina (bulk-Al), and 50 and 13 nm AlNP during entire pregnancy period. Aluminum contents in the hippocampus of newborns were measured and neurodevelopmental behaviors were tracked in the offspring from birth to 1 month of age. Furthermore, oxidative stress and neurotransmitter levels were measured in the cerebral cortex of the adolescents. Our results showed that aluminum contents in the hippocampus of newborns in AlNP-treated groups were significantly higher than those in bulk-Al and controls. Moreover, the offspring delivered by AlNP-treated female mice displayed stunted neurodevelopmental behaviors. Finally, the offspring of AlNP-treated mice demonstrated significantly increased anxiety-like behavior with impaired learning and memory performance at 1 month of age. The underlying mechanism could be related to increased oxidative stress and decreased neurotransmitter levels in the cerebral cortex. We therefore conclude that AlNP exposure of female mice during pregnancy can induce neurodevelopmental toxicity in offspring.

  9. Animal model of autism induced by prenatal exposure to valproate: behavioral changes and liver parameters.

    Science.gov (United States)

    Bambini-Junior, Victorio; Rodrigues, Leticia; Behr, Guilherme Antônio; Moreira, José Cláudio Fonseca; Riesgo, Rudimar; Gottfried, Carmem

    2011-08-23

    Autism is characterized by behavioral impairments in three main domains: social interaction; language, communication and imaginative play; and range of interests and activities. This syndrome has attracted social attention by its high prevalence. The animal model induced by prenatal exposure to valproic acid (VPA) has been proposed to study autism. Several characteristics of behavioral abnormalities found in the VPA rats, such as repetitive/stereotypic-like activity and deficit in social interaction have been correlated with autism. Features like flexibility to change strategy, social memory and metabolic status of the induced rats have not been examined. Thus, the main aim of this work was to investigate additional behavioral rodent similarities with autism, as well as, liver redox parameters after prenatal exposure to VPA. Young rats from the VPA group presented aberrant approach to a stranger rat, decreased conditioned place preference to conspecifics, normal spatial learning and a lack of flexibility to change their strategy. As adults, they presented inappropriate social approach to a stranger rat, decreased preference for social novelty, apparently normal social recognition and no spatial learning deficits. Examination of the liver from the VPA group presented significantly increased (12%) levels of catalase (CAT) activity, no alteration in superoxide dismutase (SOD) activity and a decrease in the SOD/CAT ratio. TBARS, sulfhydril and carbonyl contents, and serum levels of aminotransferases remained unchanged. In summary, rats prenatally exposed to VPA presented decreased flexibility to change strategy and social impairments similar to the autism symptoms, contributing to the understanding of neurodevelopmental symptoms and oxidative imbalance associated to the autism spectrum disorder. Copyright © 2011. Published by Elsevier B.V.

  10. Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

    Directory of Open Access Journals (Sweden)

    Caroline Clouard

    Full Text Available This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d. infusions of 15% glucose (F(Glu, lithium chloride (F(LiCl, or saline (control treatment, F(NaCl. One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl than the F(NaCl or F(Glu meals. During the two-choice tests performed one and five weeks later, the F(NaCl and F(Glu foods were significantly preferred over the F(LICl food even in the absence of i.d. infusions. Surprisingly, the F(NaCl food was also preferred over the F(Glu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

  11. Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

    Science.gov (United States)

    Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

    2012-01-01

    This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (F(Glu)), lithium chloride (F(LiCl)), or saline (control treatment, F(NaCl)). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18)FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl) than the F(NaCl) or F(Glu) meals. During the two-choice tests performed one and five weeks later, the F(NaCl) and F(Glu) foods were significantly preferred over the F(LICl) food even in the absence of i.d. infusions. Surprisingly, the F(NaCl) food was also preferred over the F(Glu) food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

  12. Postnatal odorant exposure induces peripheral olfactory plasticity at the cellular level.

    Science.gov (United States)

    Cadiou, Hervé; Aoudé, Imad; Tazir, Bassim; Molinas, Adrien; Fenech, Claire; Meunier, Nicolas; Grosmaitre, Xavier

    2014-04-02

    Mammalian olfactory sensory neurons (OSNs) form the primary elements of the olfactory system. Inserted in the olfactory mucosa lining of the nasal cavity, they are exposed to the environment and their lifespan is brief. Several reports say that OSNs are regularly regenerated during the entire life and that odorant environment affects the olfactory epithelium. However, little is known about the impact of the odorant environment on OSNs at the cellular level and more precisely in the context of early postnatal olfactory exposure. Here we exposed MOR23-green fluorescent protein (GFP) and M71-GFP mice to lyral or acetophenone, ligands for MOR23 or M71, respectively. Daily postnatal exposure to lyral induces plasticity in the population of OSNs expressing MOR23. Their density decreases after odorant exposure, whereas the amount of MOR23 mRNA and protein remain stable in the whole epithelium. Meanwhile, quantitative PCR indicates that each MOR23 neuron has higher levels of olfactory receptor transcripts and also expresses more CNGA2 and phosphodiesterase 1C, fundamental olfactory transduction pathway proteins. Transcript levels return to baseline after 4 weeks recovery. Patch-clamp recordings reveal that exposed MOR23 neurons respond to lyral with higher sensitivity and broader dynamic range while the responses' kinetics were faster. These effects are specific to the odorant-receptor pair lyral-MOR23: there was no effect of acetophenone on MOR23 neurons and no effect of acetophenone and lyral on the M71 population. Together, our results clearly demonstrate that OSNs undergo specific anatomical, molecular, and functional adaptation when chronically exposed to odorants in the early stage of life.

  13. Exposure to Gulf War Illness chemicals induces functional muscarinic receptor maladaptations in muscle nociceptors.

    Science.gov (United States)

    Cooper, B Y; Johnson, R D; Nutter, T J

    2016-05-01

    Chronic pain is a component of the multisymptom disease known as Gulf War Illness (GWI). There is evidence that pain symptoms could have been a consequence of prolonged and/or excessive exposure to anticholinesterases and other GW chemicals. We previously reported that rats exposed, for 8 weeks, to a mixture of anticholinesterases (pyridostigmine bromide, chlorpyrifos) and a Nav (voltage activated Na(+) channel) deactivation-inhibiting pyrethroid, permethrin, exhibited a behavior pattern that was consistent with a delayed myalgia. This myalgia-like behavior was accompanied by persistent changes to Kv (voltage activated K(+)) channel physiology in muscle nociceptors (Kv7, KDR). In the present study, we examined how exposure to the above agents altered the reactivity of Kv channels to a muscarinic receptor (mAChR) agonist (oxotremorine-M). Comparisons between muscle nociceptors harvested from vehicle and GW chemical-exposed rats revealed that mAChR suppression of Kv7 activity was enhanced in exposed rats. Yet in these same muscle nociceptors, a Stromatoxin-insensitive component of the KDR (voltage activated delayed rectifier K(+) channel) exhibited decreased sensitivity to activation of mAChR. We have previously shown that a unique mAChR-induced depolarization and burst discharge (MDBD) was exaggerated in muscle nociceptors of rats exposed to GW chemicals. We now provide evidence that both muscle and vascular nociceptors of naïve rats exhibit MDBD. Examination of the molecular basis of the MDBD in naïve animals revealed that while the mAChR depolarization was independent of Kv7, the action potential burst was modulated by Kv7 status. mAChR depolarizations were shown to be dependent, in part, on TRPA1. We argue that dysfunction of the MDBD could be a functional convergence point for maladapted ion channels and receptors consequent to exposure to GW chemicals. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Exposure to Sexual Stimuli Induces Greater Discounting Leading to Increased Involvement in Cyber Delinquency Among Men.

    Science.gov (United States)

    Cheng, Wen; Chiou, Wen-Bin

    2018-02-01

    People frequently encounter sexual stimuli during Internet use. Research has shown that stimuli inducing sexual motivation can lead to greater impulsivity in men, as manifested in greater temporal discounting (i.e., a tendency to prefer smaller, immediate gains to larger, future ones). Extant findings in crime research suggest that delinquents tend to focus on short-term gains while failing to adequately think through the longer-term consequences of delinquent behavior. We experimentally tested the possibility that exposure to sexual stimuli is associated with the tendency to engage in cyber delinquency among men, as a result of their overly discounting remote consequences. In Experiment 1, participants exposed to pictures of "sexy" women were more likely to discount the future and were more inclined to make cyber-delinquent choices (e.g., cyberbullying, cyber fraud, cyber theft, and illegal downloading), compared with male participants who rated the sex appeal of less sexy opposite-sex pictures. However, these relationships were not observed in female participants exposed to either highly or less sexy pictures of men. In Experiment 2, male participants exposed to sexual primes showed a greater willingness to purchase a wide range of counterfeit rather than authentic products online and experienced a higher likelihood of logging into the other person's Facebook webpage (i.e., invading online privacy). The discounting tendency mediated the link between exposure to sexual primes and the inclination to engage in cyber-delinquent behavior. These findings provide insight into a strategy for reducing men's involvement in cyber delinquency; that is, through less exposure to sexual stimuli and promotion of delayed gratification. The current results suggest that the high availability of sexual stimuli in cyberspace may be more closely associated with men's cyber-delinquent behavior than previously thought.

  15. Acute exposure to vibration is an apoptosis-inducing stimulus in the vocal fold epithelium.

    Science.gov (United States)

    Novaleski, Carolyn K; Kimball, Emily E; Mizuta, Masanobu; Rousseau, Bernard

    2016-10-01

    Clinical voice disorders pose significant communication-related challenges to patients. The purpose of this study was to quantify the rate of apoptosis and tumor necrosis factor-alpha (TNF-α) signaling in vocal fold epithelial cells in response to increasing time-doses and cycle-doses of vibration. 20 New Zealand white breeder rabbits were randomized to three groups of time-doses of vibration exposure (30, 60, 120min) or a control group (120min of vocal fold adduction and abduction). Estimated cycle-doses of vocal fold vibration were extrapolated based on mean fundamental frequency. Laryngeal tissue specimens were evaluated for apoptosis and gene transcript and protein levels of TNF-α. Results revealed that terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was significantly higher after 120min of vibration compared to the control. Transmission electron microscopy (TEM) revealed no significant effect of time-dose on the mean area of epithelial cell nuclei. Extrapolated cycle-doses of vibration exposure were closely related to experimental time-dose conditions, although no significant correlations were observed with TUNEL staining or mean area of epithelial cell nuclei. TUNEL staining was positively correlated with TNF-α protein expression. Our findings suggest that apoptosis can be induced in the vocal fold epithelium after 120min of modal intensity phonation. In contrast, shorter durations of vibration exposure do not result in apoptosis signaling. However, morphological features of apoptosis are not observed using TEM. Future studies are necessary to examine the contribution of abnormal apoptosis to vocal fold diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Cytogenetic Damages Induced by Chronic Exposure to Microwave Non-Ionizing Radiofrequency Fields

    Directory of Open Access Journals (Sweden)

    Boris Đinđić

    2013-12-01

    Full Text Available Non-ionizing radiation has a significant and positive impact on modern society through a number of uses. There is increasing public concern regarding the health risks of radio-frequency (RF radiation, particularly that produced by mobile phones. Concern regarding the potential risks of exposure to EMFs has led to many epidemiological investigations, but the effects of EMF exposure on human and other mammalian cells are still unclear. One of the most frequently asked questions about the effects of microwave radiation on biological systems is whether they produce genotoxic effects and could be there a possible link with oncogenic processes. It is most difficult to get accurate and reproducible results for the studies that tell us most about the effects of EMF on humans. Based on some “weak” evidence suggesting an association between exposure to radiofrequency fields (RF emitted from mobile phones and two types of brain cancer, glioma and acoustic neuroma, the International Agency for Research on Cancer has classified RF as ‘possibly carcinogenic to humans’ in group 2B. Literature results suggest that pulsed microwaves from working environment can be the cause of genetic and cell alterations. Taken together, the increased frequency of DNA damages, increased intensity of oxydative stress and production of reactive oxygen species as well as prolonged disruption in DNA repair mechanisms could be possible mechanisms for microwave induced cytogenetic damages even at low-level electromagnetic fields. Although there were contradictory results about harmful effects of electromagnetic fields we recommend that the mobile phone should be kept as far as possible from the body during conversations and also during usual daily activities to reduce the absorption of radiation by cells. In addition, the appropriate intake of antioxidant-rich food or drugs may be helpful for preventing the genotoxic effects that could be caused by mobile phone use.

  17. Transcriptomic configuration of mouse brain induced by adolescent exposure to 3,4-methylenedioxymethamphetamine

    International Nuclear Information System (INIS)

    Eun, Jung Woo; Kwack, Seung Jun; Noh, Ji Heon; Jung, Kwang Hwa; Kim, Jeong Kyu; Bae, Hyun Jin; Xie Hongjian; Ryu, Jae Chun; Ahn, Young Min; Min, Jin-Hye; Park, Won Sang; Lee, Jung Young; Rhee, Gyu Seek; Nam, Suk Woo

    2009-01-01

    The amphetamine derivative (±)-3,4-methylenedioxymethamphetamine (MDMA or ecstasy) is a synthetic amphetamine analogue used recreationally to obtain an enhanced affiliative emotional response. MDMA is a potent monoaminergic neurotoxin with the potential to damage brain serotonin and/or dopamine neurons. As the majority of MDMA users are young adults, the risk that users may expose the fetus to MDMA is a concern. However, the majority of studies on MDMA have investigated the effects on adult animals. Here, we investigated whether long-term exposure to MDMA, especially in adolescence, could induce comprehensive transcriptional changes in mouse brain. Transcriptomic analysis of mouse brain regions demonstrated significant gene expression changes in the cerebral cortex. Supervised analysis identified 1028 genes that were chronically dysregulated by long-term exposure to MDMA in adolescent mice. Functional categories most represented by this MDMA characteristic signature are intracellular molecular signaling pathways of neurotoxicity, such as, the MAPK signaling pathway, the Wnt signaling pathway, neuroactive ligand-receptor interaction, long-term potentiation, and the long-term depression signaling pathway. Although these resultant large-scale molecular changes remain to be studied associated with functional brain damage caused by MDMA, our observations delineate the possible neurotoxic effects of MDMA on brain function, and have therapeutic implications concerning neuro-pathological conditions associated with MDMA abuse.

  18. Radon-induced cancer: a cell-based model of tumorigenesis due to protracted exposures

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1994-01-01

    In 1982, results with C3H mouse embryo cells showed that the frequency of neoplastic transformation was enhanced when exposures to fission-spectrum neutrons were protracted in time. This finding was unexpected because the opposite was found with low-LET radiations. Similar neutron enhancements were reported with normal life-span Syrian hamster embryo cells, and with human hybrid cells. Because other studies did not confirm the preceding, in 1990 - at a conference convened by the US Armed Forces Radiobiological Research Institute - a biophysical model was proposed to explain the basis for the enhancement observed in some experiments but not in others. The model attributed special sensitivities, related to killing and neoplastic transformation, to cells in and around mitosis. Subsequently, it was shown that late G 2 /M phase cells constituted this window of sensitivity. In the instance of tumorigenesis, the model predicted that protracted exposures to a high-LET radiation would result in enhanced frequencies of transformation providing that susceptible cells were cycling or could be induced to cycle. The model explained data on lung tumour induction in rats breathing radon at different concentrations, and uranium miners working in atmospheres containing different concentrations of radon. The model also explains the anomalous finding that lung cancer deaths are often sublinearly correlated with indoor radon concentration. (author)

  19. Significant modulation of the hepatic proteome induced by exposure to low temperature in Xenopus laevis

    Directory of Open Access Journals (Sweden)

    Kazumichi Nagasawa

    2013-08-01

    The African clawed frog, Xenopus laevis, is an ectothermic vertebrate that can survive at low environmental temperatures. To gain insight into the molecular events induced by low body temperature, liver proteins were evaluated at the standard laboratory rearing temperature (22°C, control and a low environmental temperature (5°C, cold exposure. Using nano-flow liquid chromatography coupled with tandem mass spectrometry, we identified 58 proteins that differed in abundance. A subsequent Gene Ontology analysis revealed that the tyrosine and phenylalanine catabolic processes were modulated by cold exposure, which resulted in decreases in hepatic tyrosine and phenylalanine, respectively. Similarly, levels of pyruvate kinase and enolase, which are involved in glycolysis and glycogen synthesis, were also decreased, whereas levels of glycogen phosphorylase, which participates in glycogenolysis, were increased. Therefore, we measured metabolites in the respective pathways and found that levels of hepatic glycogen and glucose were decreased. Although the liver was under oxidative stress because of iron accumulation caused by hepatic erythrocyte destruction, the hepatic NADPH/NADP ratio was not changed. Thus, glycogen is probably utilized mainly for NADPH supply rather than for energy or glucose production. In conclusion, X. laevis responds to low body temperature by modulating its hepatic proteome, which results in altered carbohydrate metabolism.

  20. Exposure to Mozart music reduces cognitive impairment in pilocarpine-induced status epilepticus rats.

    Science.gov (United States)

    Xing, Yingshou; Qin, Yi; Jing, Wei; Zhang, Yunxiang; Wang, Yanran; Guo, Daqing; Xia, Yang; Yao, Dezhong

    2016-02-01

    Patients with temporal lobe epilepsy (TLE) often display cognitive deficits. However, current epilepsy therapeutic interventions mainly aim at how to reduce the frequency and degree of epileptic seizures. Recovery of cognitive impairment is not attended enough, resulting in the lack of effective approaches in this respect. In the pilocarpine-induced temporal lobe epilepsy rat model, memory impairment has been classically reported. Here we evaluated spatial cognition changes at different epileptogenesis stages in rats of this model and explored the effects of long-term Mozart music exposure on the recovery of cognitive ability. Our results showed that pilocarpine rats suffered persisting cognitive impairment during epileptogenesis. Interestingly, we found that Mozart music exposure can significantly enhance cognitive ability in epileptic rats, and music intervention may be more effective for improving cognitive function during the early stages after Status epilepticus. These findings strongly suggest that Mozart music may help to promote the recovery of cognitive damage due to seizure activities, which provides a novel intervention strategy to diminish cognitive deficits in TLE patients.

  1. Binge-pattern alcohol exposure during puberty induces long-term changes in HPA axis reactivity.

    Directory of Open Access Journals (Sweden)

    Magdalena M Przybycien-Szymanska

    2011-04-01

    Full Text Available Adolescence is a dynamic and important period of brain development however, little is known about the long-term neurobiological consequences of alcohol consumption during puberty. Our previous studies showed that binge-pattern ethanol (EtOH treatment during pubertal development negatively dysregulated the responsiveness of the hypothalamo-pituitary-adrenal (HPA axis, as manifested by alterations in corticotrophin-releasing hormone (CRH, arginine vasopressin (AVP, and corticosterone (CORT during this time period. Thus, the primary goal of this study was to determine whether these observed changes in important central regulators of the stress response were permanent or transient. In this study, juvenile male Wistar rats were treated with a binge-pattern EtOH treatment paradigm or saline alone for 8 days. The animals were left undisturbed until adulthood when they received a second round of treatments consisting of saline alone, a single dose of EtOH, or a second binge-pattern treatment paradigm. The results showed that pubertal binge-pattern EtOH exposure induced striking long-lasting alterations of many HPA axis parameters. Overall, our data provide strong evidence that binge-pattern EtOH exposure during pubertal maturation has long-term detrimental effects for the healthy development of the HPA axis.

  2. Perfluorooctanoic acid exposure induces endoplasmic reticulum stress in the liver and its effects are ameliorated by 4-phenylbutyrate.

    Science.gov (United States)

    Yan, Shengmin; Zhang, Hongxia; Wang, Jianshe; Zheng, Fei; Dai, Jiayin

    2015-10-01

    Perfluoroalkyl acids (PFAAs) are a group of widely used anthropogenic compounds. As one of the most dominant PFAAs, perfluorooctanoic acid (PFOA) has been suggested to induce hepatotoxicity and several other toxicological effects. However, details on the mechanisms for PFOA-induced hepatotoxicity still need to be elucidated. In this study, we observed the occurrence of endoplasmic reticulum (ER) stress in mouse livers and HepG2 cells after PFOA exposure using several familiar markers for the unfolded protein response (UPR). ER stress in HepG2 cells after PFOA exposure was not significantly influenced by autophagy inhibition or stimulation. The antioxidant defense system was significantly disturbed in mouse livers after PFOA exposure, and reactive oxygen species (ROS) were increased in cells exposed to PFOA for 24 h. However, N-acetyl-L-cysteine (NAC) pretreatment did not satisfactorily alleviate the UPR in cells exposed to PFOA even though the increase of ROS was less evident. Furthermore, exposure of HepG2 cells to PFOA in the presence of sodium 4-phenylbutyrate (4-PBA), a chemical chaperone and ER stress inhibitor, suggested that 4-PBA alleviated the UPR and autophagosome accumulation induced by PFOA in cells. In addition, several toxicological effects attributed to PFOA exposure, including cell cycle arrest, proteolytic activity impairment, and neutral lipid accumulation, were also improved by 4-PBA cotreatment in cells. In vivo study demonstrated that PFOA-induced lipid metabolism perturbation and liver injury were partially ameliorated by 4-PBA in mice after 28 days of exposure. These findings demonstrated that PFOA-induced ER stress leading to UPR might play an important role in PFOA-induced hepatotoxic effects, and chemical chaperone 4-PBA could ameliorate the effects. Copyright © 2015. Published by Elsevier Inc.

  3. Metallothionein blocks oxidative DNA damage induced by acute inorganic arsenic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Wei, E-mail: qu@niehs.nih.gov; Waalkes, Michael P.

    2015-02-01

    We studied how protein metallothionein (MT) impacts arsenic-induced oxidative DNA damage (ODD) using cells that poorly express MT (MT-I/II double knockout embryonic cells; called MT-null cells) and wild-type (WT) MT competent cells. Arsenic (as NaAsO{sub 2}) was less cytolethal over 24 h in WT cells (LC{sub 50} = 11.0 ± 1.3 μM; mean ± SEM) than in MT-null cells (LC{sub 50} = 5.6 ± 1.2 μM). ODD was measured by the immuno-spin trapping method. Arsenic (1 or 5 μM; 24 h) induced much less ODD in WT cells (121% and 141% of control, respectively) than in MT-null cells (202% and 260%). In WT cells arsenic caused concentration-dependent increases in MT expression (transcript and protein), and in the metal-responsive transcription factor-1 (MTF-1), which is required to induce the MT gene. In contrast, basal MT levels were not detectable in MT-null cells and unaltered by arsenic exposure. Transfection of MT-I gene into the MT-null cells markedly reduced arsenic-induced ODD levels. The transport genes, Abcc1 and Abcc2 were increased by arsenic in WT cells but either showed no or very limited increases in MT-null cells. Arsenic caused increases in oxidant stress defense genes HO-1 and GSTα2 in both WT and MT-null cells, but to much higher levels in WT cells. WT cells appear more adept at activating metal transport systems and oxidant response genes, although the role of MT in these responses is unclear. Overall, MT protects against arsenic-induced ODD in MT competent cells by potential sequestration of scavenging oxidant radicals and/or arsenic. - Highlights: • Metallothionein blocks arsenic toxicity. • Metallothionein reduces arsenic-induced DNA damage. • Metallothionein may bind arsenic or radicals produced by arsenic.

  4. Technical-economic feasibility of orbiting sunlight reflectors

    Science.gov (United States)

    Alferov, Z.; Minin, V.

    1986-02-01

    The use of deflectors in orbit as a means of providing artificial illumination is examined. Considerations of technical and economic feasibility are addressed. Three main areas of application are distinguished: reflecting sunlight onto the surface of the Earth; concentration of the flow of solar energy on an orbiting receiver; and retransmission of optical radiation. The advantages of the artificial Earth illumination application of the orbiting reflector scheme in terms of energy savings in lighting cities, and additional daylight time for critical periods of farming operations are discussed.

  5. The use of docosahexaenoic acid supplementation to ameliorate the hyperactivity of rat pups induced by in utero ethanol exposure

    OpenAIRE

    Furuya, Hiroyuki; Aikawa, Hiroyuki; Yoshida, Takahiko; Okazaki, Isao

    2000-01-01

    It has been demonstrated thatin utero ethanol (EtOH) exposure induces hyperactive behavior and learning disturbances in offspring. In order to investigate the effects of docosahexaenoic acid (DHA) on these neurobehavioral dysfunctions of rat pups induced byin utero EtOH exposure, pregnant Wistar rats were divided into four treatment groups depending on the type of oil added to the diet and drinking water as follows; (a) 5% safflower oil with tap water (TW/n-6), (b) 3% safflower oil and 2% DHA...

  6. Sun Exposure Prevalence and Associated Skin Health Habits: Results from the Austrian Population-Based UVSkinRisk Survey

    Directory of Open Access Journals (Sweden)

    Daniela Haluza

    2016-01-01

    Full Text Available Recreational sun exposure accounts for a large number of acute and chronic dermatological diseases, including skin cancer. This study aimed at estimating the one-year prevalence of sun exposure and skin health-associated knowledge and attitudes among Austrian citizens. The population-based UVSkinRisk survey investigated a representative sample of Austrian adults using a structured questionnaire. In total, 1500 study subjects (median age 33.0 years, 50.5% females participated in this questionnaire survey. Among study participants, prevalence of sun exposure was 47%, with slightly higher rates in males (48% compared to females (46%. Younger age, lower professional category, darker skin type, motives to tan, sunbed use, sunburn, and outdoor sport activity increased the odds for prevalent sun exposure. This is the first population-based study evaluating the prevailing sun exposure and recreational habits influencing skin health among Austrian citizens. Despite public media campaigns educating on the harmful effects of sunlight exposure, we found a high prevalence of self-reported sunlight exposure. The results suggest that multifaceted socio-cultural characteristics stimulate recreational sun exposure and tanning habits. Communicating individualized Public (Skin Health messages might be the key to prevent photo-induced skin health hazards in light-skinned populations. The practical and theoretical implications of these findings are discussed.

  7. Acrylonitrile potentiates hearing loss and cochlear damage induced by moderate noise exposure in rats

    International Nuclear Information System (INIS)

    Pouyatos, BenoIt; Gearhart, Caroline A.; Fechter, Laurence D.

    2005-01-01

    The diversity of chemical and drugs that can potentiate noise-induced hearing loss (NIHL) has impeded efforts to predict such interactions. We have hypothesized that chemical contaminants that disrupt intrinsic antioxidant defenses hold significant risk for potentiating NIHL. If this is true, then acrylonitrile (ACN) would be expected to potentiate NIHL. ACN, one of the 50 most commonly used chemicals in the United States, is metabolized via two pathways that are likely to disrupt intrinsic reactive oxygen species (ROS) buffering systems: (1) it conjugates glutathione, depleting this important antioxidant rapidly; (2) a second pathway involves the formation of cyanide, which can inhibit superoxide dismutase. We hypothesized that moderate noise exposure, that does not produce permanent hearing loss by itself, could initiate oxidative stress and that ACN could render the inner ear more sensitive to noise by disrupting intrinsic antioxidant defenses. Temporary and persistent effects of ACN alone (50 mg/kg, sc 5 days), noise alone (95 or 97 dB octave band noise, 4 h/day for 5 days), or ACN in combination with noise were determined using distortion product otoacoustic emissions (DPOAEs) and compound action potential (CAP) amplitudes. Histopathological damage to hair cells resulting from these treatments was also investigated using surface preparations of the organ of Corti. Individually, neither ACN nor noise exposures caused any permanent hearing or hair cell loss; only a reversible temporary threshold shift was measured in noise-exposed animals. However, when given in combination, ACN and noise induced permanent threshold shifts (13-16 dB between 7 and 40 kHz) and a decrease in DPOAE amplitudes (up to 25 dB at 19 kHz), as well as significant outer hair cell (OHC) loss (up to 20% in the first row between 13 and 47 kHz). This investigation demonstrates that ACN can potentiate NIHL at noise levels that are realistic in terms of human exposure, and that the OHCs are the

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

    Directory of Open Access Journals (Sweden)

    Jill R Johnson

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

  9. Simulating sleep apnea by exposure to intermittent hypoxia induces inflammation in the lung and liver.

    Science.gov (United States)

    da Rosa, Darlan Pase; Forgiarini, Luiz Felipe; Baronio, Diego; Feijó, Cristiano Andrade; Martinez, Dênis; Marroni, Norma Possa

    2012-01-01

    Sleep apnea is a breathing disorder that results from momentary and cyclic collapse of the upper airway, leading to intermittent hypoxia (IH). IH can lead to the formation of free radicals that increase oxidative stress, and this mechanism may explain the association between central sleep apnea and nonalcoholic steatohepatitis. We assessed the level of inflammation in the lung and liver tissue from animals subjected to intermittent hypoxia and simulated sleep apnea. A total of 12 C57BL/6 mice were divided into two groups and then exposed to IH (n = 6) or a simulated IH (SIH) (n = 6) for 35 days. We observed an increase in oxidative damage and other changes to endogenous antioxidant enzymes in mice exposed to IH. Specifically, the expression of multiple transcription factors, including hypoxia inducible factor (HIF-1α), nuclear factor kappa B (NF-κB), and tumor necrosis factor (TNF-α), inducible NO synthase (iNOS), vascular endothelial growth factor (VEGF), and cleaved caspase 3 were shown to be increased in the IH group. Overall, we found that exposure to intermittent hypoxia for 35 days by simulating sleep apnea leads to oxidative stress, inflammation, and increased activity of caspase 3 in the liver and lung.

  10. Simulating Sleep Apnea by Exposure to Intermittent Hypoxia Induces Inflammation in the Lung and Liver

    Directory of Open Access Journals (Sweden)

    Darlan Pase da Rosa

    2012-01-01

    Full Text Available Sleep apnea is a breathing disorder that results from momentary and cyclic collapse of the upper airway, leading to intermittent hypoxia (IH. IH can lead to the formation of free radicals that increase oxidative stress, and this mechanism may explain the association between central sleep apnea and nonalcoholic steatohepatitis. We assessed the level of inflammation in the lung and liver tissue from animals subjected to intermittent hypoxia and simulated sleep apnea. A total of 12 C57BL/6 mice were divided into two groups and then exposed to IH (n=6 or a simulated IH (SIH (n=6 for 35 days. We observed an increase in oxidative damage and other changes to endogenous antioxidant enzymes in mice exposed to IH. Specifically, the expression of multiple transcription factors, including hypoxia inducible factor (HIF-1α, nuclear factor kappa B (NF-κB, and tumor necrosis factor (TNF-α, inducible NO synthase (iNOS, vascular endothelial growth factor (VEGF, and cleaved caspase 3 were shown to be increased in the IH group. Overall, we found that exposure to intermittent hypoxia for 35 days by simulating sleep apnea leads to oxidative stress, inflammation, and increased activity of caspase 3 in the liver and lung.

  11. [Changes of the Expression of Brain Derived Neurotrophic Factors in Rats Trachea Induced by Acrolein Exposure].

    Science.gov (United States)

    Yuan, Bing; Yang, Rui-an; Zhao, Wei; Xu, Yan-yan; Dan, Qi-qin; Zhang, Yun-hui

    2015-07-01

    To investigate expressional changes of brain derived neurotrophic factor (BDNF) in the trachea of rats with acrolein inhalation. Twenty two SD rats were divided into 2 groups: the rats in experimental group were subjected to acrolein inhalation for the induce of trachea inflammatory injury, while the rats with saline (NS) inhalation were as control. All the rats were sacrificed in 1,3,6 weeks after acrolein (n = 11 at each time point) or saline inhalation (n = 11 at each time point), the samples of trachea epithelium were harvested. The immunohistochemistry and in situ hybridization was performed to detect the location of BDNF protein and mRNA in trachea. The expression of BDNF mRNA in the trachea tissues were determined by RT-PCR. There are positive cells in epithelium of trachea for BDNF protein and mRNA, with cytoplasm staining. The expression of BDNF mRNA in the trachea was increased at 1 week after acrolein inhalation (P 0.05). The inflammatory injury in trachea induced by acrolein exposure could be associated with the increased expression of BDNF. BDNF may be one of the crucial inflammatory factors in the process of inflammatory reaction in trachea with acrolein stimulation.

  12. Studies on chromosome aberrations induced in human lymphocytes by very low-dose exposure to tritium

    International Nuclear Information System (INIS)

    Hori, T.; Moriya, Junko; Nakai, Sayaka

    1978-01-01

    Assessment of potential hazard from environmental tritium to man becomes very important with increasing the development of nuclear-power industry. However, little data are available as to the determination on the genetic effect of tritium especially at the low levels. The object of the present study is to obtain quantitative data for chromosome aberrations in human lymphocytes, as an indicator for genetic risk estimation, induced by tritium at very low dose levels. Leukocyte cultures of human peripheral blood were chronically exposed for 48h to tritiated water and 3 H-thymidine using a wide range of tritium doses, and aberrations in lymphocyte chromosomes at the first metaphases were examined. In the experimental conditions, the types of aberrations induced by radiation emitted from both tritiated water and 3 H-thymidine were mostly chromatid types, such as chromatid gaps and deletions. The dose-response relations for chromatid breaks per cell exhibited unusual dose-dependency in both cases. It was demonstrated that at higher dose range the yields of chromatid breaks increased linearly with dose, while those at lower dose range were significantly higher than would be expected by a downward extraporation from the linear relation. Partial-hit or partial-target kinetics events appeared at very low dose exposure. (author)

  13. Perinatal exposure to lead induces morphological, ultrastructural and molecular alterations in the hippocampus

    International Nuclear Information System (INIS)

    Baranowska-Bosiacka, I.; Strużyńska, L.; Gutowska, I.; Machalińska, A.; Kolasa, A.; Kłos, P.; Czapski, G.A.; Kurzawski, M.; Prokopowicz, A.; Marchlewicz, M.

    2013-01-01

    Highlights: ► Pre- and neonatal Pb exposure decreased the number of hippocampal neurons. ► Lead caused ultrastructural alterations in CA1 region of hippocampus. ► Hippocampus is highly vulnerable to low level perinatal Pb exposure. ► Lead decreased BDNF level in the developing brain. ► Decreased Bax/Bcl2 ratio may protect hippocampus against Pb-induced apoptosis. -- Abstract: The aim of this paper is to examine if pre- and neonatal exposure to lead (Pb) may intensify or inhibit apoptosis or necroptosis in the developing rat brain. Pregnant experimental females received 0.1% lead acetate (PbAc) in drinking water from the first day of gestation until weaning of the offspring; the control group received distilled water. During the feeding of pups, mothers from the experimental group were still receiving PbAc. Pups were weaned at postnatal day 21 and the young rats of both groups then received only distilled water until postnatal day 28. This treatment protocol resulted in a concentration of Pb in rat offspring whole blood (Pb-B) below the threshold of 10 μg/dL, considered safe for humans.We studied Casp-3 activity and expression, AIF nuclear translocation, DNA fragmentation, as well as Bax, Bcl-2 mRNA and protein expression as well as BDNF concentration in selected structures of the rat brain: forebrain cortex (FC), cerebellum (C) and hippocampus (H). The microscopic examinations showed alterations in hippocampal neurons.Our data shows that pre- and neonatal exposure of rats to Pb, leading to Pb-B below 10 μg/dL, can decrease the number of hippocampus neurons, occurring concomitantly with ultrastructural alterations in this region. We observed no morphological or molecular features of severe apoptosis or necrosis (no active Casp-3 and AIF translocation to nucleus) in young brains, despite the reduced levels of BDNF. The potential protective factor against apoptosis was probably the decreased Bax/Bcl-2 ratio, which requires further investigation. Our

  14. Polychlorinated biphenyls exposure-induced insulin resistance is mediated by lipid droplet enlargement through Fsp27.

    Science.gov (United States)

    Kim, Hye Young; Kwon, Woo Young; Kim, Yeon A; Oh, Yoo Jin; Yoo, Seung Hee; Lee, Mi Hwa; Bae, Ju Yong; Kim, Jong-Min; Yoo, Young Hyun

    2017-06-01

    Although epidemiological and experimental studies demonstrated that polychlorinated biphenyls (PCBs) lead to insulin resistance, the mechanism underlying PCBs-induced insulin resistance has remained unsolved. In this study, we examined in vitro and in vivo effects of PCB-118 (dioxin-like PCB) and PCB-138 (non-dioxin-like PCB) on adipocyte differentiation, lipid droplet growth, and insulin action. 3T3-L1 adipocytes were incubated with PCB-118 or PCB-138 during adipocyte differentiation. For in vivo studies, C57BL/6 mice were administered PCB-118 or PCB-138 (37.5 mg/kg) by intraperitoneal injection and we examined adiposity and whole-body insulin action. PCB-118 and PCB-138 significantly promoted adipocyte differentiation and increased the lipid droplet (LD) size in 3T3-L1 adipocytes. In mice, both PCBs increased adipose mass and adipocyte size. Furthermore, both PCBs induced insulin resistance in vitro and in vivo. Expression of fat-specific protein 27 (Fsp27), which is localized to LD contact sites, was increased in PCB-treated 3T3-L1 adipocytes and mice. Depletion of Fsp27 by siRNA resulted in the inhibition of LD enlargement and attenuation of insulin resistance in PCB-treated 3T3-L1 adipocytes. An anti-diabetic drug, metformin, attenuated insulin resistance in PCB-treated 3T3-L1 adipocytes through the reduced expression of Fsp27 protein and LD size. This study suggests that PCB exposure-induced insulin resistance is mediated by LD enlargement through Fsp27.

  15. Protective effects of selenium on mercury induced immunotoxic effects in mice by way of concurrent drinking water exposure.

    Science.gov (United States)

    Li, Xuan; Yin, Daqiang; Li, Jiang; Wang, Rui

    2014-07-01

    Selenium (Se) has been recognized as one key to understanding mercury (Hg) exposure risks. To explore the effects of Se on Hg-induced immunotoxicity, female Balb/c mice were exposed to HgCl2- or MeHgCl-contaminated drinking water (0.001, 0.01, and 0.1 mM as Hg) with coexisting Na2SeO3 at different Se/Hg molar ratios (0:1, 1/3:1, 1:1 and 3:1). The potential immunotoxicity induced by Na2SeO3 exposure alone (by way of drinking water) was also determined within a wide range of concentrations. After 14 days' exposure, the effects of Hg or Se on the immune system of Balb/c mice were investigated by determining the proliferation of T and B lymphocytes and the activity of natural killer cells. Hg exposure alone induced a dose-dependent suppression effect, whereas Se provided promotion effects at low exposure level (0.03 mM). Under Hg and Se coexposure condition, the effects on immunotoxicity depended on the Hg species, Se/Hg ratio, and exposure concentration. At low Hg concentration (0.001 mM), greater Se ingestion exhibited stronger protective effects on Hg-induced suppression effect mainly by way of decreasing Hg concentrations in target organs. At greater Hg concentration (0.01 and 0.1 mM), immunotoxicity induced by Se (>0.03 mM) became evident, and the protective effects appeared more significant at an Se/Hg molar ratio of 1:1. The complex antagonistic effects between Se and Hg suggested that both Se/Hg molar ratio and concentration should be considered when evaluating the potential health risk of Hg-contaminated biota.

  16. Ocean color remote sensing using polarization properties of reflected sunlight

    Science.gov (United States)

    Frouin, R.; Pouliquen, E.; Breon, F.-M.

    1994-01-01

    The effects of the atmosphere and surface on sunlight backscattered to space by the ocean may be substantially reduced by using the unpolarized component of reflectance instead of total reflectance. At 450 nm, a wavelength of interest in ocean color remote sensing, and for typical conditions, 45% of the unpolarized reflectance may originate from the water body instead of 20% of the total reflectance, which represents a gain of a factor 2.2 in useful signal for water composition retrieval. The best viewing geometries are adjacent to the glitter region; they correspond to scattering angles around 100 deg, but they may change slightly depending on the polarization characteristics of the aerosols. As aerosol optical thickness increases, the atmosphere becomes less efficient at polarizing sunlight, and the enhancement of the water body contribution to unpolarized reflectance is reduced. Since the perturbing effects are smaller on unpolarized reflectance, at least for some viewing geometries, they may be more easily corrected, leading to a more accurate water-leaving signal and, therefore, more accurate estimates of phytoplankton pigment concentration.

  17. Maternal house dust mite exposure during pregnancy enhances severity of house dust mite-induced asthma in murine offspring.

    Science.gov (United States)

    Richgels, Phoebe K; Yamani, Amnah; Chougnet, Claire A; Lewkowich, Ian P

    2017-11-01

    Atopic status of the mother and maternal exposure to environmental factors are associated with increased asthma risk. Moreover, animal models demonstrate that exposure to allergens in strongly sensitized mothers influences offspring asthma development, suggesting that in utero exposures can influence offspring asthma. However, it is unclear whether maternal exposure to common human allergens such as house dust mite (HDM), in the absence of additional adjuvants, influences offspring asthma development. We sought to determine whether maternal HDM exposure influences asthma development in offspring. Pregnant female mice were exposed to PBS or HDM during pregnancy. Using offspring of PBS- or HDM-exposed mothers, the magnitude of HDM or Aspergillus fumigatus (AF) extract-induced airway hyperresponsiveness (AHR), airway inflammation, immunoglobulin production, T H 2-associated cytokine synthesis, and pulmonary dendritic cell activity was assessed. Compared with offspring of PBS-exposed mothers, offspring of HDM-exposed mothers demonstrate increased AHR, airway inflammation, T H 2 cytokine production, and immunoglobulin levels and a modest decrease in the phagocytic capacity of pulmonary macrophage populations following HDM exposure. Increased sensitivity to AF-induced airway disease was not observed. Offspring of HDM-exposed B-cell-deficient mothers also demonstrated increased HDM-induced AHR, suggesting that transfer of maternal immunoglobulins is not required. Our data demonstrate that maternal exposure to HDM during pregnancy increases asthma sensitivity in offspring in an HDM-specific manner, suggesting that vertical transmission of maternal immune responses may be involved. These findings have important implications for regulation of asthma risk, and suggest that exposure to HDM in the developed world may have underappreciated influences on the overall prevalence of allergic asthma. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by

  18. Exposure to UV radiation and human health

    Science.gov (United States)

    Kimlin, Michael G.

    2005-08-01

    This paper will overview the significant issues facing researchers in relating the impact of exposure to sunlight and human health. Exposure to solar ultraviolet radiation is the major causative factor in most sun-related skin and eye disorders, however, very little is known quantitatively about human UV exposures. Interestingly, human exposure to sunlight also has a nutritional impact, namely the development of pre-Vitamin D, which is an important nutrient in bone health. New research suggest that low vitamin D status may be a causative factor in the development of selective types of cancer and autoimminue diseases, as well as a contributing factor in bone health. The 'health duality' aspect of sunlight exposure is an interesting and controversial topic that is a research focus of Kimlin's research group.

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

    Directory of Open Access Journals (Sweden)

    Fernando B. R. da Silva

    2018-05-01

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

  20. Sunlight-exposed biofilm microbial communities are naturally resistant to chernobyl ionizing-radiation levels.

    Science.gov (United States)

    Ragon, Marie; Restoux, Gwendal; Moreira, David; Møller, Anders Pape; López-García, Purificación

    2011-01-01

    The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general diversity patterns, despite increased mutation levels at the single

  1. Effect of artificial sunlight on the retention of external calcein marks on lake trout

    Science.gov (United States)

    Honeyfield, D.C.; Kehler, T.; Fletcher, J.W.; Mohler, J.W.

    2008-01-01

    When choosing a fish marking technique to address fishery related questions, it is important to consider factors that affect mark retention. Calcein, a chemical marking agent, is under investigation for potential use on fish. Two laboratory trials were conducted with calcein-marked lake trout Salvelinus namaycush to determine the effect of artificial sunlight on calcein mark intensity. In trial 1, fish exposed to 18,000 lx for 7 d lost 90% or more of the calcein mark intensity (relative to the colorimetric key, mg/L) on the head, body, ventral region, and pectoral fins relative to mark intensity in fish that were maintained in darkness. In trial 2, light intensity was reduced 2.5-3.0-fold. After 7 d of light exposure, calcein mark intensity on the head was reduced by 40-45% relative to mark intensity in fish that were held in darkness; by day 14, calcein mark intensity on the head was reduced by 55-60% relative to that of dark-treated fish. No further decline was observed in light-exposed fish, and head mark intensity values did not differ among days 14, 21, and 28 for this treatment group. Of the four areas evaluated, the head and pectoral fin were more easily read using a colorimetric key than the lateral or ventral regions of the fish. The concentration of calcein spotted on filter paper to devise the colorimetric key ranged from 1 to 100 mg/L. A difference of approximately 7 mg/L in apparent calcein mark intensity means for the head region could be detected using the colorimetric key. These trials showed that calcein mark intensity on lake trout declined when fish were exposed to artificial sunlight, and the use of a colorimetric key improved the objectivity of calcein mark intensity assessment.

  2. On the anisotropy of stress-distribution induced in glasses and crystals by non-ablative femtosecond laser exposure

    NARCIS (Netherlands)

    McMillen, B.W.; Bellouard, Y.

    2015-01-01

    Femtosecond laser exposure in the non-ablative regime induces a variety of bulk structural modifications, in which anisotropy may depend on the polarization of the writing beam. In this work, we investigate the correlation between polarization state and stress anisotropy. In particular, we introduce

  3. Nitrogen narcosis induced by repetitive hyperbaric nitrogen oxygen mixture exposure impairs long-term cognitive function in newborn mice.

    Directory of Open Access Journals (Sweden)

    Bin Peng

    Full Text Available Human beings are exposed to compressed air or a nitrogen-oxygen mixture, they will produce signs and symptoms of nitrogen narcosis such as amnesia or even loss of memory, which may be disappeared once back to the normobaric environment. This study was designed to investigate the effect of nitrogen narcosis induced by repetitive hyperbaric nitrogen-oxygen mixture exposure on long-term cognitive function in newborn mice and the underlying mechanisms. The electroencephalogram frequency was decreased while the amplitude was increased in a pressure-dependent manner during 0.6, 1.2, 1.8 MPa (million pascal nitrogen-oxygen mixture exposures in adult mice. Nitrogen narcosis in postnatal days 7-9 mice but not in adult mice induced by repetitive hyperbaric exposure prolonged the latency to find the platform and decreased the number of platform-site crossovers during Morris water maze tests, and reduced the time in the center during the open field tests. An increase in the expression of cleaved caspase-3 in the hippocampus and cortex were observed immediately on the first day after hyperbaric exposure, and this lasted for seven days. Additionally, nitrogen narcosis induced loss of the dendritic spines but not of the neurons, which may mainly account for the cognitive dysfunction. Nitrogen narcosis induced long-term cognitive and emotional dysfunction in the postnatal mice but not in the adult mice, which may result from neuronal apoptosis and especially reduction of dendritic spines of neurons.

  4. Frequent extreme cold exposure and brown fat and cold-induced thermogenesis: A study in a monozygotic twin

    NARCIS (Netherlands)

    M.J. Vosselman (Maarten J.); G.H.E.J. Vijgen (Guy H. E. J.); B.R.M. Kingma (Boris R. M.); B. Brans (Boudewijn); W.D. Van Marken Lichtenbelt (Wouter D.)

    2014-01-01

    textabstractIntroduction: Mild cold acclimation is known to increase brown adipose tissue (BAT) activity and cold-induced thermogenesis (CIT) in humans. We here tested the effect of a lifestyle with frequent exposure to extreme cold on BAT and CIT in a Dutch man known as 'the Iceman', who has

  5. Exposure to reactive intermediate-inducing drugs during pregnancy and the incident use of psychotropic medications among children

    NARCIS (Netherlands)

    Tran, Yen-Hao; Groen, Henk; Bergman, Jorieke E H; Hak, Eelko; Wilffert, Bob

    Purpose Our study aimed to investigate the association between prenatal exposure to reactive intermediate (RI)-inducing drugs and the initiation of psychotropic medications among children. Methods We designed a cohort study using a pharmacy prescription database. Pregnant women were considered

  6. Exposure to time varying magnetic fields associated with magnetic resonance imaging reduces fentanyl-induced analgesia in mice

    Energy Technology Data Exchange (ETDEWEB)

    Teskey, G.C.; Prato, F.S.; Ossenkopp, K.P.; Kavaliers, M.

    1988-01-01

    The effects of exposure to clinical magnetic resonance imaging (MRI) on analgesia induced by the mu opiate agonist, fentanyl, was examined in mice. During the dark period, adult male mice were exposed for 23.2 min to the time-varying (0.6 T/sec) magnetic field (TVMF) component of the MRI procedure. Following this exposure, the analgesic potency of fentanyl citrate (0.1 mg/kg) was determined at 5, 10, 15, and 30 min post-injection, using a thermal test stimulus (hot-plate 50 degrees C). Exposure to the magnetic-field gradients attenuated the fentanyl-induced analgesia in a manner comparable to that previously observed with morphine. These results indicate that the time-varying magnetic fields associated with MRI have significant inhibitory effects on the analgesic effects of specific mu-opiate-directed ligands.

  7. Ultrastructural effects on gill, muscle, and gonadal tissues induced in zebrafish (Danio rerio) by a waterborne uranium exposure

    International Nuclear Information System (INIS)

    Barillet, Sabrina; Larno, Valerie; Floriani, Magali; Devaux, Alain; Adam-Guillermin, Christelle

    2010-01-01

    Experiments on adult zebrafish (Danio rerio) were conducted to assess histopathological effects induced on gill, muscle, and gonadal tissues after waterborne uranium exposure. Although histopathology is often employed as a tool for the detection and assessment of xenobiotic-mediated effects in aquatic organisms, few studies have been dedicated to the investigation of histopathological consequences of uranium exposure in fish. Results showed that gill tissue architecture was markedly disrupted. Major symptoms were alterations of the secondary lamellae epithelium (from extensive oedema to desquamation), hyperplasia of chloride cells, and breakdown of the pillar cell system. Muscle histology was also affected. Degeneration and disorganization of myofibrillar sarcomeric pattern as well as abnormal localization of mitochondria within muscle and altered endomysial sheaths were observed. Morphological alterations of spermatozoa within the gonadal tissue were also noticed. This study demonstrated that uranium exposure induced a variety of histological impairments in fish, supporting environmental concerns when uranium contaminates aquatic systems.

  8. Ultrastructural effects on gill, muscle, and gonadal tissues induced in zebrafish (Danio rerio) by a waterborne uranium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, Sabrina, E-mail: sabrina.barillet@free.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Larno, Valerie, E-mail: valerie.larno@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Devaux, Alain, E-mail: alain.devaux@entpe.fr [INRA, EFPA Department, 54280, Champenoux and Environmental Science Laboratory, ENTPE, 69518 Vaulx en Velin cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological Protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France)

    2010-11-01

    Experiments on adult zebrafish (Danio rerio) were conducted to assess histopathological effects induced on gill, muscle, and gonadal tissues after waterborne uranium exposure. Although histopathology is often employed as a tool for the detection and assessment of xenobiotic-mediated effects in aquatic organisms, few studies have been dedicated to the investigation of histopathological consequences of uranium exposure in fish. Results showed that gill tissue architecture was markedly disrupted. Major symptoms were alterations of the secondary lamellae epithelium (from extensive oedema to desquamation), hyperplasia of chloride cells, and breakdown of the pillar cell system. Muscle histology was also affected. Degeneration and disorganization of myofibrillar sarcomeric pattern as well as abnormal localization of mitochondria within muscle and altered endomysial sheaths were observed. Morphological alterations of spermatozoa within the gonadal tissue were also noticed. This study demonstrated that uranium exposure induced a variety of histological impairments in fish, supporting environmental concerns when uranium contaminates aquatic systems.

  9. BISPHENOL A EXPOSURE DURING EARLY DEVELOPMENT INDUCES SEX-SPECIFIC CHANGES IN ADULT ZEBRAFISH SOCIAL INTERACTIONS

    Science.gov (United States)

    Weber, Daniel N.; Hoffmann, Raymond G.; Hoke, Elizabeth S.; Tanguay, Robert L.

    2014-01-01

    Developmental bisphenol A (BPA) exposure is associated with adverse behavioral effects, although underlying modes of action remain unclear. Because BPA is a suspected xenoestrogen, the objective was to identify sex-based changes in adult zebrafish social behavior developmentally exposed to BPA (0.0, 0.1 or 1 μM) or one of two control compounds (0.1μM 17β-estradiol [E2], and 0.1 μM GSK4716, a synthetic estrogen-related receptor γ ligand). A test chamber was divided lengthwise so each arena held one fish unable to detect the presence of the other fish. A mirror was inserted at one end of each arena; baseline activity levels were determined without mirror. Arenas were divided into 3, computer-generated zones to represent different distances from mirror image. Circadian rhythm patterns were evaluated at 1–3 (= AM) and 5–8 (= PM) hr postprandial. Adult zebrafish were placed into arenas and monitored by digital camera for 5 min. Total distance traveled, % time spent at mirror image, and number of attacks on mirror image were quantified. E2, GSK4716, and all BPA treatments dampened male activity and altered male circadian activity patterns; there was no marked effect on female activity. BPA induced non-monotonic effects (response curve changes direction within range of concentrations examined) on male % time at mirror only in AM. All treatments produced increased % time at the mirror during PM. Male attacks on the mirror were reduced by BPA exposure only during AM. There were sex-specific effects of developmental BPA on social interactions and time-of-day of observation affected results. PMID:25424546

  10. Exposure-dependent variation in cryolite induced lethality in the nontarget insect, Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Podder Sayanti

    2014-03-01

    Full Text Available The starting point of toxicity testing of any chemical in an organism is the determination of its Lethal Concentration 50 (LC50. In the present study, LC50 of a fluorinated insecticide cryolite is determined in a non-target insect model, Drosophila melanogaster. Interestingly, the result shows that acute LC50 of cryolite was much greater in comparison to the chronic one in case of Drosophila larvae. Larvae which were exposed to 65,000 to 70,000 μg/ml cryolite through food showed 50% mortality after 18 hours of acute exposure, whereas only 150 to 160 μg/ml cryolite was sufficient to cause 50% mortality in case of chronic exposure. Thus cryolite in a small amount when applied once cannot produce noticeable changes in Drosophila, whereas the same amount when used continuously can be fatal. The non-feeding pupal stage was also seen to be affected by chemical treatment. This suggests that the test chemical affects the developmental fate and results in failure of adult emergence. Absence of chemical-induced mortality in adults assumes that the toxicity of cryolite might be restricted to the preimaginal stages of the organism. Reduction in body size of larvae after ingestion of cryolite (with food in acute treatment schedule is another interesting finding of this study. Some individuals consuming cryolite containing food cannot survive whereas the few survivors manifest a significant growth retardation which might be due to a tendency of refusal in feeding. Hence the present findings provide a scope of assessment of risk of other similar non-target groups

  11. Noise-induced hearing loss and combined noise and vibration exposure.

    Science.gov (United States)

    Turcot, A; Girard, S A; Courteau, M; Baril, J; Larocque, R

    2015-04-01

    While there is a wide body of literature addressing noise-induced hearing loss (NIHL) and hand-arm vibration syndrome (HAVS) independently, relatively few studies have considered the combined effects of noise and vibration. These studies have suggested an increased risk of NIHL in workers with vibration white finger (VWF), though the relationship remains poorly understood. To determine whether hearing impairment is worse in noise-exposed workers with VWF than in workers with similar noise exposures but without VWF. The Quebec National Institute of Public Health audiometric database was used in conjunction with work-related accident and occupational diseases data from the Quebec workers' compensation board to analyse differences in audiometry results between vibration-exposed workers in the mining and forestry industries and the overall source population, and between mining and forestry workers with documented VWF and those without VWF. The International Organization for Standardization (ISO) 7029 standards were used to calculate hearing loss not attributable to age. 15751 vibration-exposed workers were identified in an overall source population of 59339. Workers with VWF (n = 96) had significantly worse hearing at every frequency studied (500, 1000, 2000 4000 Hz) compared with other mining and forestry workers without VWF. This study confirms previous findings of greater hearing loss at higher frequencies in workers with VWF, but also found a significant difference in hearing loss at low frequencies. It therefore supports the association between combined noise and hand-arm vibration (HAV) exposure and NIHL. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. DNA damage in lymphocytes induced by cardiac CT and comparison with physical exposure parameters

    Energy Technology Data Exchange (ETDEWEB)

    Fukumoto, Wataru; Tatsugami, Fuminari; Awai, Kazuo [Department of Diagnostic Radiology, Institute of Biomedical Health Sciences, Hiroshima University, Hiroshima (Japan); Ishida, Mari; Sakai, Chiemi [Institute of Biomedical and Health Sciences, Department of Cardiovascular Physiology and Medicine, Hiroshima University, Hiroshima (Japan); Tashiro, Satoshi [Hiroshima University, Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima (Japan); Ishida, Takafumi [Institute of Clinical Research West Medical Center, Hiroshima (Japan); Nakano, Yukiko [Hiroshima University Hospital, Department of Cardiovascular Medicine, Hiroshima (Japan)

    2017-04-15

    To investigate whether physical exposure parameters such as the dose index (CTDI), dose length product (DLP), and size-specific dose estimate (SSDE) are predictive of DNA damage. In vitro, we scanned a phantom containing blood samples from five volunteers at CTDI 50, 100, and 150 mGy. One sample was not scanned. We also scanned samples in three different-size phantoms at CTDI 100 mGy. In vivo, we enrolled 45 patients and obtained blood samples before and after cardiac CT. The γ-H2AX foci were counted. In vitro, in the control and at CTDI 50, 100, and 150 mGy, the number of γ-H2AX was 0.94 ± 0.24 (standard error, SE), 1.28 ± 0.30, 1.91 ± 0.47, and 2.16 ± 0.20. At SSDE 180, 156, and 135 mGy, it was 2.41 ± 0.20, 1.91 ± 0.47, and 1.42 ± 0.20 foci/cell. The γ-H2AX foci were positively correlated with the radiation dose and negatively correlated with the body size. In vivo, the γ-H2AX foci were significantly increased after CT (from 1.21 ± 0.19 to 1.92 ± 0.22 foci/cell) and correlated with CTDI, DLP, and SSDE. DNA damage was induced by cardiac CT. There was a correlation between the physical exposure parameters and γ-H2AX. (orig.)

  13. A generic approach for sunlight and shadow impact computation on large city models

    OpenAIRE

    Jaillot , Vincent; Pedrinis , Frédéric; Servigne , Sylvie; Gesquière , Gilles

    2017-01-01

    International audience; Study of sunlight and shadow effects on the city has become more accessible with the development of 3D citymodels. It allows measuring when and how an object is exposed to the sunlight, which enables conducting manyrelated studies such as energy analyses or urban planning. While many works have been done for this purpose, itmay be interesting to know which objects (terrain, buildings, trees, etc.) prevent other objects from beingexposed to the sunlight. In this paper w...

  14. The effect of post-conditioning exposure to morphine on the retention of a morphine-induced conditioned taste aversion.

    Science.gov (United States)

    Jacobs, W J; Zellner, D A; LoLordo, V M; Riley, A L

    1981-06-01

    In the following experiment, multiple injections of morphine sulfate following the acquisition of a morphine-induced taste aversion had no effect on the retention of the previously acquired aversion. Post-conditioning injections of morphine resulted in the development of physical dependence to morphine and led to a decrement in the ability of morphine to induce a subsequent aversion to a second novel taste. This failure of post-conditioning exposures to morphine to affect a previously acquired morphine-induced taste aversion even though tolerance to morphine had occurred was discussed in the context of Rescorla's event-memory model of conditioning.

  15. Tobacco smoke exposure suppresses radiation-induced inflammation in the lung

    International Nuclear Information System (INIS)

    Bjermer, L.; Cai, Y.; Nilsson, K.; Hellstroem, S.; Henriksson, R.

    1993-01-01

    Previous studies on patients with breast cancer, who received postsurgical irradiation, displayed a markedly suppressed inflammatory response in the lung of smoking patients compared to nonsmokers. The aim of the present study was to investigate further the effect of exposure to tobacco smoke on the development of irradiation-induced pneumonitis in the rat. Four groups of animals were used: controls (C); those exposed to tobacco smoke (S); those irradiated but not exposed to smoke (RNS); and those irradiated and exposed to tobacco smoke (RS). The rats were exposed to a diluted main stream of cigarette smoke, at a concentration of about 0.4 mgxl -1 , in a nose-only exposure system for 1 hxday -1 , 5 daysxweek -1 for 10 weeks. Exposure to tobacco smoke started 3 weeks before irradiation. The basal one third of both lungs was exposed to a single radiation dose of 28 Gy (6 MeV photons). All animals were killed 7 weeks after irradiation. We compared findings in bronchoalveolar lavage (BAL) and tissue morphology. The alveolar tissue showed less inflammation in the RS-group than in the RNS-group. Most strikingly, mast cells were increased one hundredfold in the lung interstitium and thirty fold in the peribronchial area in the RNS-group, whereas no increase was found in the RS-group or in the controls. The alveolar septa of the RNS-group were thickened, with occurrence of inflammatory cells and mast cells, whereas the RS-group displayed no difference as compared to the non-irradiated, nonsmoking group (C). There was a marked discrepancy between the findings in BAL and tissue of the alveolar space or lung interstitium. In BAL, neutrophils, and to a lesser extent lymphocytes, were increased both in the RS- and RNS-group; however, with significantly higher numbers in the RNS-group. In contrast, the cells in the alveolar space and interstitium were dominated by mononuclear cells, mainly macrophages. Moreover, a more than twenty fold increase in total cells in the alveolar

  16. Environmentally toxicant exposures induced intragenerational transmission of liver abnormalities in mice

    Directory of Open Access Journals (Sweden)

    Mohamed A. Al-Griw

    2017-08-01

    Full Text Available Environmental toxicants such as chemicals, heavy metals, and pesticides have been shown to promote transgenerational inheritance of abnormal phenotypes and/or diseases to multiple subsequent generations following parental and/ or ancestral exposures. This study was designed to examine the potential transgenerational action of the environmental toxicant trichloroethane (TCE on transmission of liver abnormality, and to elucidate the molecular etiology of hepatocyte cell damage. A total of thirty two healthy immature female albino mice were randomly divided into three equal groups as follows: a sham group, which did not receive any treatment; a vehicle group, which received corn oil alone, and TCE treated group (3 weeks, 100 μg/kg i.p., every 4th day. The F0 and F1 generation control and TCE populations were sacrificed at the age of four months, and various abnormalities histpathologically investigated. Cell death and oxidative stress indices were also measured. The present study provides experimental evidence for the inheritance of environmentally induced liver abnormalities in mice. The results of this study show that exposure to the TCE promoted adult onset liver abnormalities in F0 female mice as well as unexposed F1 generation offspring. It is the first study to report a transgenerational liver abnormalities in the F1 generation mice through maternal line prior to gestation. This finding was based on careful evaluation of liver histopathological abnormalities, apoptosis of hepatocytes, and measurements of oxidative stress biomarkers (lipid peroxidation, protein carbonylation, and nitric oxide in control and TCE populations. There was an increase in liver histopathological abnormalities, cell death, and oxidative lipid damage in F0 and F1 hepatic tissues of TCE treated group. In conclusion, this study showed that the biological and health impacts of environmental toxicant TCE do not end in maternal adults, but are passed on to offspring

  17. Methylmercury Exposure Induces Sexual Dysfunction in Male and Female Drosophila Melanogaster.

    Science.gov (United States)

    Chauhan, Ved; Srikumar, Syian; Aamer, Sarah; Pandareesh, Mirazkar D; Chauhan, Abha

    2017-09-24

    Mercury, an environmental health hazard, is a neurotoxic heavy metal. In this study, the effect of methylmercury (MeHg) exposure was analyzed on sexual behavior in Drosophila melanogaster (fruit fly), because neurons play a vital role in sexual functions. The virgin male and female flies were fed a diet mixed with different concentrations of MeHg (28.25, 56.5, 113, 226, and 339 µM) for four days, and the effect of MeHg on copulation of these flies was studied. While male and female control flies (no MeHg) and flies fed with lower concentrations of MeHg (28.25, 56.5 µM) copulated in a normal manner, male and female flies exposed to higher concentrations of MeHg (113, 226, and 339 µM) did not copulate. When male flies exposed to higher concentrations of MeHg were allowed to copulate with control female flies, only male flies fed with 113 µM MeHg were able to copulate. On the other hand, when female flies exposed to higher concentrations of MeHg were allowed to copulate with control male flies, none of the flies could copulate. After introduction of male and female flies in the copulation chamber, duration of wing flapping by male flies decreased in a MeHg-concentration-dependent manner from 101 ± 24 seconds (control) to 100.7 ± 18, 96 ±12, 59 ± 44, 31 ± 15, and 3.7 ± 2.7 seconds at 28.25, 56.5, 113, 226, and 339 µM MeHg, respectively. On the other hand, grooming in male and female flies increased in a MeHg-concentration-dependent manner. These findings suggest that MeHg exposure causes sexual dysfunction in male and female Drosophila melanogaster . Further studies showed that MeHg exposure increased oxidative stress and decreased triglyceride levels in a concentration-dependent manner in both male and female flies, suggesting that MeHg-induced oxidative stress and decreased triglyceride levels may partly contribute to sexual dysfunction in fruit flies.

  18. Sensitivity analysis for direct and indirect effects in the presence of exposure-induced mediator-outcome confounders

    Science.gov (United States)

    Chiba, Yasutaka

    2014-01-01

    Questions of mediation are often of interest in reasoning about mechanisms, and methods have been developed to address these questions. However, these methods make strong assumptions about the absence of confounding. Even if exposure is randomized, there may be mediator-outcome confounding variables. Inference about direct and indirect effects is particularly challenging if these mediator-outcome confounders are affected by the exposure because in this case these effects are not identified irrespective of whether data is available on these exposure-induced mediator-outcome confounders. In this paper, we provide a sensitivity analysis technique for natural direct and indirect effects that is applicable even if there are mediator-outcome confounders affected by the exposure. We give techniques for both the difference and risk ratio scales and compare the technique to other possible approaches. PMID:25580387

  19. Phosphoramide mustard exposure induces DNA adduct formation and the DNA damage repair response in rat ovarian granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2015-02-01

    Phosphoramide mustard (PM), the ovotoxic metabolite of the anti-cancer agent cyclophosphamide (CPA), destroys rapidly dividing cells by forming NOR-G-OH, NOR-G and G-NOR-G adducts with DNA, potentially leading to DNA damage. A previous study demonstrated that PM induces ovarian DNA damage in rat ovaries. To investigate whether PM induces DNA adduct formation, DNA damage and induction of the DNA repair response, rat spontaneously immortalized granulosa cells (SIGCs) were treated with vehicle control (1% DMSO) or PM (3 or 6 μM) for 24 or 48 h. Cell viability was reduced (P < 0.05) after 48 h of exposure to 3 or 6 μM PM. The NOR-G-OH DNA adduct was detected after 24 h of 6 μM PM exposure, while the more cytotoxic G-NOR-G DNA adduct was formed after 48 h by exposure to both PM concentrations. Phosphorylated H2AX (γH2AX), a marker of DNA double stranded break occurrence, was also increased by PM exposure, coincident with DNA adduct formation. Additionally, induction of genes (Atm, Parp1, Prkdc, Xrcc6, and Brca1) and proteins (ATM, γH2AX, PARP-1, PRKDC, XRCC6, and BRCA1) involved in DNA repair were observed in both a time- and dose-dependent manner. These data support that PM induces DNA adduct formation in ovarian granulosa cells, induces DNA damage and elicits the ovarian DNA repair response. - Highlights: • PM forms ovarian DNA adducts. • DNA damage marker γH2AX increased by PM exposure. • PM induces ovarian DNA double strand break repair.

  20. Influence of short-term aluminum exposure on demineralized bone matrix induced bone formation

    Energy Technology Data Exchange (ETDEWEB)

    Severson, A.R. (Minnesota Univ., Duluth, MN (United States). Dept. of Anatomy and Cell Biology); Haut, C.F.; Firling, C.E. (Minnesota Univ., Duluth, MN (United States). Dept. of Biology); Huntley, T.E. (Minnesota Univ., Duluth, MN (United States). Dept. of Biochemistry and Molecular Biology)

    1992-12-01

    The effects of aluminum exposure on bone formation employing the demineralized bone matrix (DBM) induced bone development model were studied using 4-week-old Sprague-Dawley rats injected with a saline (control) or an aluminum chloride (experimental) solution. After 2 weeks of aluminum treatment, 20-mg portions of rat DBM were implanted subcutaneously on each side in the thoracic region of the control and experimental rats. Animals were killed 7, 12, or 21 days after implantation of the DBM and the developing plaques removed. No morphological, histochemical, or biochemical differences were apparent between plaques from day 7 control and experimental rats. Plaques from day 12 control and experimental rats exhibited cartilage formation and alkaline phosphatase activity localized in osteochondrogenic cells, chondrocytes, osteoblasts, and extracellular matrix. Unlike the plaques from control rats that contained many osteoblastic mineralizing fronts, the plaques from the 12-day experimental group had a preponderance of cartilaginous tissue, no evidence of mineralization, increased levels of alkaline phosphatase activity, and a reduced calcium content. Plaques developing for 21 days in control animals demonstrated extensive new bone formation and bone marrow development, while those in the experimental rats demonstrated unmineralized osteoid-like matrix with poorly developed bone marrow. Alkaline phosphatase activity of the plaques continued to remain high on day 21 for the control and experimental groups. Calcium levels were significantly reduced in the experimental group. These biochemical changes correlated with histochemical reductions in bone calcification. Thus, aluminum administration to rats appears to alter the differentiation and calcification of developing cartilage and bone in the DBM-induced bone formation model and suggests that aluminum by some mechanism alters the matrix calcification in growing bones. (orig.).

  1. Exposure to nerve growth factor worsens nephrotoxic effect induced by Cyclosporine A in HK-2 cells.

    Directory of Open Access Journals (Sweden)

    Donatella Vizza

    Full Text Available Nerve growth factor is a neurotrophin that promotes cell growth, differentiation, survival and death through two different receptors: TrkA(NTR and p75(NTR. Nerve growth factor serum concentrations increase during many inflammatory and autoimmune diseases, glomerulonephritis, chronic kidney disease, end-stage renal disease and, particularly, in renal transplant. Considering that nerve growth factor exerts beneficial effects in the treatment of major central and peripheral neurodegenerative diseases, skin and corneal ulcers, we asked whether nerve growth factor could also exert a role in Cyclosporine A-induced graft nephrotoxicity. Our hypothesis was raised from basic evidence indicating that Cyclosporine A-inhibition of calcineurin-NFAT pathway increases nerve growth factor expression levels. Therefore, we investigated the involvement of nerve growth factor and its receptors in the damage exerted by Cyclosporine A in tubular renal cells, HK-2. Our results showed that in HK-2 cells combined treatment with Cyclosporine A + nerve growth factor induced a significant reduction in cell vitality concomitant with a down-regulation of Cyclin D1 and up-regulation of p21 levels respect to cells treated with Cyclosporine A alone. Moreover functional experiments showed that the co-treatment significantly up-regulated human p21promoter activity by involvement of the Sp1 transcription factor, whose nuclear content was negatively regulated by activated NFATc1. In addition we observed that the combined exposure to Cyclosporine A + nerve growth factor promoted an up-regulation of p75 (NTR and its target genes, p53 and BAD leading to the activation of intrinsic apoptosis. Finally, the chemical inhibition of p75(NTR down-regulated the intrinsic apoptotic signal. We describe two new mechanisms by which nerve growth factor promotes growth arrest and apoptosis in tubular renal cells exposed to Cyclosporine A.

  2. Blue light-induced oxidative stress in live skin.

    Science.gov (United States)

    Nakashima, Yuya; Ohta, Shigeo; Wolf, Alexander M

    2017-07-01

    Skin damage from exposure to sunlight induces aging-like changes in appearance and is attributed to the ultraviolet (UV) component of light. Photosensitized production of reactive oxygen species (ROS) by UVA light is widely accepted to contribute to skin damage and carcinogenesis, but visible light is thought not to do so. Using mice expressing redox-sensitive GFP to detect ROS, blue light could produce oxidative stress in live skin. Blue light induced oxidative stress preferentially in mitochondria, but green, red, far red or infrared light did not. Blue light-induced oxidative stress was also detected in cultured human keratinocytes, but the per photon efficacy was only 25% of UVA in human keratinocyte mitochondria, compared to 68% of UVA in mouse skin. Skin autofluorescence was reduced by blue light, suggesting flavins are the photosensitizer. Exposing human skin to the blue light contained in sunlight depressed flavin autofluorescence, demonstrating that the visible component of sunlight has a physiologically significant effect on human skin. The ROS produced by blue light is probably superoxide, but not singlet oxygen. These results suggest that blue light contributes to skin aging similar to UVA. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Early life exposure to a rodent carcinogen propiconazole fungicide induces oxidative stress and hepatocarcinogenesis in medaka fish

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Tzu-Yi; Hong, Chwan-Yang [Department of Agricultural Chemistry, College of Bio-Resources and Agriculture, National Taiwan University, Taipei, Taiwan (China); Sasado, Takao [Laboratory of Bioresources, National Institute for Basic Biology, Okazaki (Japan); Kashiwada, Shosaku [Research Center for Life and Environmental Sciences, Department of Life Sciences, the Toyo University, Gunma (Japan); Chen, Pei-Jen, E-mail: chenpj@ntu.edu.tw [Department of Agricultural Chemistry, College of Bio-Resources and Agriculture, National Taiwan University, Taipei, Taiwan (China)

    2016-01-15

    Highlights: • Propiconazole initiates ROS-induced oxidative stress and damage in medaka fish. • Early life exposure to propiconazole increases incidence of hepatocarcionogensis in p53{sup −/−} medaka. • Oxidative stress and CYP induction involved in p53 regulation are key events in propiconazole-induced hepatotumorigenesis. • Propiconazole-induced toxic response in medaka is compatible with that in rodents. - Abstract: Conazole pollution is an emerging concern to human health and environmental safety because of the broad use of conazole fungicides in agriculture and medicine and their frequent occurrence in aquifers. The agricultural pesticide propiconazole has received much regulatory interest because it is a known rodent carcinogen with evidence of multiple adverse effects in mammals and non-targeted organisms. However, the carcinogenic effect and associated mechanism of propiconazole in fish under microgram-per-liter levels of environmental-relevant exposure remains unclear. To explore whether early life of propiconzaole exposure would induce oxidative stress and latent carcinogenic effects in fish, we continuously exposed larvae of wild type or p53{sup −/−} mutant of medaka fish (Oryzias latipes) to propiconazole (2.5–250 μg/L) for 3, 7, 14 or 28 days and assessed liver histopathology and/or the oxidative stress response and gene expression during exposure and throughout adulthood. Propiconazole dose-dependently induced reactive oxygen species (ROS) level, altered homeostasis of antioxidant superoxide dismutase, catalase and glutathione S-transferase and caused lipid and protein peroxidation during early life exposure in wild type medaka. Such exposure also significantly upregulated gene expression of the cytochrome P450 CYP1A, but marginally suppressed that of tumor suppressor p53 in adults. Furthermore, histopathology revealed that p53{sup −/−} mutant medaka with early life exposure to propiconazole showed increased incidence of

  4. Early life exposure to a rodent carcinogen propiconazole fungicide induces oxidative stress and hepatocarcinogenesis in medaka fish

    International Nuclear Information System (INIS)

    Tu, Tzu-Yi; Hong, Chwan-Yang; Sasado, Takao; Kashiwada, Shosaku; Chen, Pei-Jen

    2016-01-01

    Highlights: • Propiconazole initiates ROS-induced oxidative stress and damage in medaka fish. • Early life exposure to propiconazole increases incidence of hepatocarcionogensis in p53"−"/"− medaka. • Oxidative stress and CYP induction involved in p53 regulation are key events in propiconazole-induced hepatotumorigenesis. • Propiconazole-induced toxic response in medaka is compatible with that in rodents. - Abstract: Conazole pollution is an emerging concern to human health and environmental safety because of the broad use of conazole fungicides in agriculture and medicine and their frequent occurrence in aquifers. The agricultural pesticide propiconazole has received much regulatory interest because it is a known rodent carcinogen with evidence of multiple adverse effects in mammals and non-targeted organisms. However, the carcinogenic effect and associated mechanism of propiconazole in fish under microgram-per-liter levels of environmental-relevant exposure remains unclear. To explore whether early life of propiconzaole exposure would induce oxidative stress and latent carcinogenic effects in fish, we continuously exposed larvae of wild type or p53"−"/"− mutant of medaka fish (Oryzias latipes) to propiconazole (2.5–250 μg/L) for 3, 7, 14 or 28 days and assessed liver histopathology and/or the oxidative stress response and gene expression during exposure and throughout adulthood. Propiconazole dose-dependently induced reactive oxygen species (ROS) level, altered homeostasis of antioxidant superoxide dismutase, catalase and glutathione S-transferase and caused lipid and protein peroxidation during early life exposure in wild type medaka. Such exposure also significantly upregulated gene expression of the cytochrome P450 CYP1A, but marginally suppressed that of tumor suppressor p53 in adults. Furthermore, histopathology revealed that p53"−"/"− mutant medaka with early life exposure to propiconazole showed increased incidence of

  5. Harvesting Water from Air: Using Anhydrous Salt with Sunlight

    KAUST Repository

    Li, Renyuan

    2018-04-02

    Atmospheric water is abundant alternative water resource, equivalent to 6 times of water in all rivers on Earth. This work screens 14 common anhydrous and hydrated salt couples in terms of their physical and chemical stability, water vapor harvesting and release capacity under relevant application scenarios. Among the salts screened, copper chloride (CuCl2), copper sulfate (CuSO4) and magnesium sulfate (MgSO4) distinguish themselves and are further made into bi-layer water collection devices, with the top layer being photothermal layer while the bottom layer being salt-loaded fibrous membrane. The water collection devices are capable of capturing water vapor out of the air with low relative humidity (down to 15 %) and releasing water under regular and even weakened sunlight (i.e. 0.7 kW/m2). The work shines light on the potential use of anhydrous salt towards producing drinking water in water scarce regions.

  6. Spatial learning and memory deficits induced by exposure to iron-56-particle radiation

    Science.gov (United States)

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

    2000-01-01

    It has previously been shown that exposing rats to particles of high energy and charge (HZE) disrupts the functioning of the dopaminergic system and behaviors mediated by this system, such as motor performance and an amphetamine-induced conditioned taste aversion; these adverse behavioral and neuronal effects are similar to those seen in aged animals. Because cognition declines with age, spatial learning and memory were assessed in the Morris water maze 1 month after whole-body irradiation with 1.5 Gy of 1 GeV/nucleon high-energy (56)Fe particles, to test the cognitive behavioral consequences of radiation exposure. Irradiated rats demonstrated cognitive impairment compared to the control group as seen in their increased latencies to find the hidden platform, particularly on the reversal day when the platform was moved to the opposite quadrant. Also, the irradiated group used nonspatial strategies during the probe trials (swim with no platform), i.e. less time spent in the platform quadrant, fewer crossings of and less time spent in the previous platform location, and longer latencies to the previous platform location. These findings are similar to those seen in aged rats, suggesting that an increased release of reactive oxygen species may be responsible for the induction of radiation- and age-related cognitive deficits. If these decrements in behavior also occur in humans, they may impair the ability of astronauts to perform critical tasks during long-term space travel beyond the magnetosphere.

  7. Malathion exposure modulates hypothalamic gene expression and induces dyslipedemia in Wistar rats.

    Science.gov (United States)

    Rezg, Raja; Mornagui, Bessem; Benahmed, Malika; Chouchane, Sonia Gharsalla; Belhajhmida, Nadia; Abdeladhim, Maha; Kamoun, Abdelaziz; El-fazaa, Saloua; Gharbi, Najoua

    2010-06-01

    Exposure to organophosphate (OP) pesticides is virtually ubiquitous. These inevitable agents are neurotoxicants, but recent evidence also points to lasting effects on carbohydrate metabolism. The aim of this study was to investigate the effects of 32 repeated treatment days with malathion, an OP insecticide, on some molecular and metabolic parameters. Malathion at 100 mg/kg was administered by gavage in Wistar rats. Results of this study indicate a significant decrease in hypothalamic corticotropin-releasing hormone mRNA, of malathion-treated rats. This result, in accordance with that of diabetic type 2 rat model, may be due to very potent negative feedback effects of glucocorticoids on hypothalamo-pituitary-adrenal (HPA) axis activity. In addition, we have recorded a significant increase in hypothalamic inducible NO synthase mRNA which probably enhances the negative feedback. These alterations are accompanied with hypertriglyceridemia that may be a favourable condition to insulin resistance. Thus, results of the present study suggest that malathion can be considered as an important risk factor in the development of diabetes type 2, which prevalence increased substantially in our country and around the world. Clearly, we need to focus further research on the specific incidences of hazardous food chemical contaminant that might be contributing to epidemic health perspectives. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

  8. Perinatal BPA Exposure Induces Hyperglycemia, Oxidative Stress and Decreased Adiponectin Production in Later Life of Male Rat Offspring

    Directory of Open Access Journals (Sweden)

    Shunzhe Song

    2014-04-01

    Full Text Available The main object of the present study was to explore the effect of perinatal bisphenol A (BPA exposure on glucose metabolism in early and later life of male rat offspring, and to establish the potential mechanism of BPA-induced dysglycemia. Pregnant rats were treated with either vehicle or BPA by drinking water at concentrations of 1 and 10 µg/mL BPA from gestation day 6 through the end of lactation. We measured the levels of fasting serum glucose, insulin, adiponectin and parameters of oxidative stress on postnatal day (PND 50 and PND100 in male offspring, and adiponectin mRNA and protein expression in adipose tissue were also examined. Our results showed that perinatal exposure to 1 or 10 µg/mL BPA induced hyperglycemia with insulin resistance on PND100, but only 10 µg/mL BPA exposure had similar effects as early as PND50. In addition, increased oxidative stress and decreased adiponectin production were also observed in BPA exposed male offspring. Our findings indicated that perinatal exposure to BPA resulted in abnormal glucose metabolism in later life of male offspring, with an earlier and more exacerbated effect at higher doses. Down-regulated expression of adiponectin gene and increased oxidative stress induced by BPA may be associated with insulin resistance.

  9. Exposure to excess insulin (glargine) induces type 2 diabetes mellitus in mice fed on a chow diet.

    Science.gov (United States)

    Yang, Xuefeng; Mei, Shuang; Gu, Haihua; Guo, Huailan; Zha, Longying; Cai, Junwei; Li, Xuefeng; Liu, Zhenqi; Cao, Wenhong

    2014-06-01

    We have previously shown that insulin plays an important role in the nutrient-induced insulin resistance. In this study, we tested the hypothesis that chronic exposure to excess long-acting insulin (glargine) can cause typical type 2 diabetes mellitus (T2DM) in normal mice fed on a chow diet. C57BL/6 mice were treated with glargine once a day for 8 weeks, followed by evaluations of food intake, body weight, blood levels of glucose, insulin, lipids, and cytokines, insulin signaling, histology of pancreas, ectopic fat accumulation, oxidative stress level, and cholesterol content in mitochondria in tissues. Cholesterol content in mitochondria and its association with oxidative stress in cultured hepatocytes and β-cells were also examined. Results show that chronic exposure to glargine caused insulin resistance, hyperinsulinemia, and relative insulin deficiency (T2DM). Treatment with excess glargine led to loss of pancreatic islets, ectopic fat accumulation in liver, oxidative stress in liver and pancreas, and increased cholesterol content in mitochondria of liver and pancreas. Prolonged exposure of cultured primary hepatocytes and HIT-TI5 β-cells to insulin induced oxidative stress in a cholesterol synthesis-dependent manner. Together, our results show that chronic exposure to excess insulin can induce typical T2DM in normal mice fed on a chow diet. © 2014 The authors.

  10. Adolescent delta-9-tetrahydrocannabinol (THC) exposure fails to affect THC-induced place and taste conditioning in adult male rats.

    Science.gov (United States)

    Wakeford, Alison G P; Flax, Shaun M; Pomfrey, Rebecca L; Riley, Anthony L

    2016-01-01

    Adolescent initiation of drug use has been linked to problematic drug taking later in life and may represent an important variable that changes the balance of the rewarding and/or aversive effects of abused drugs which may contribute to abuse vulnerability. The current study examined the effects of adolescent THC exposure on THC-induced place preference (rewarding effects) and taste avoidance (aversive effects) conditioning in adulthood. Forty-six male Sprague-Dawley adolescent rats received eight injections of an intermediate dose of THC (3.2mg/kg) or vehicle. After these injections, animals were allowed to mature and then trained in a combined CTA/CPP procedure in adulthood (PND ~90). Animals were given four trials of conditioning with intervening water-recovery days, a final CPP test and then a one-bottle taste avoidance test. THC induced dose-dependent taste avoidance but did not produce place conditioning. None of these effects was impacted by adolescent THC exposure. Adolescent exposure to THC had no effect on THC taste and place conditioning in adulthood. The failure to see an effect of adolescent exposure was addressed in the context of other research that has assessed exposure of drugs of abuse during adolescence on drug reactivity in adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2018-08-01

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

  12. Abnormal levels of UV-induced unscheduled DNA synthesis in ataxia telangiectasia cells after exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Jaspers, N.G.J.; Nederlandse Centrale Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek, Rijswijk. Medical Biological Lab.); Bootsma, D.

    1982-01-01

    In cultured cells from normal individuals and from patients having ataxia telangiectasia (AT) the rate of unscheduled DNA synthesis (UDS) induced by UV light was investigated by autoradiography. The number of grains in 6 different AT cell strains was similar to that observed in normal cells. Exposure of normal cells to doses of X-rays up to 20 krad had no influence on the rate of UV-induced UDS. In contrast, the UV-induced UDS was significantly modified in AT cells by treatment with X-rays. In AT cell strains that were reported to have reduced levels of γ-ray-induced repair DNA synthesis ('excision-deficient' AT cells) the effect of X-rays on UV-induced UDS was inhibitory, whereas UV-induced UDS was stimulated by X-ray exposure in 'excision-proficient' AT cell strains. Different UV and X-ray dose-response relationships were seen in the two categories of AT cell strains. (orig./AJ)

  13. Exposure to reactive intermediate-inducing drugs during pregnancy and the incident use of psychotropic medications among children.

    Science.gov (United States)

    Tran, Yen-Hao; Groen, Henk; Bergman, Jorieke E H; Hak, Eelko; Wilffert, Bob

    2017-03-01

    Our study aimed to investigate the association between prenatal exposure to reactive intermediate (RI)-inducing drugs and the initiation of psychotropic medications among children. We designed a cohort study using a pharmacy prescription database. Pregnant women were considered exposed when they received a prescription of RI-inducing drugs. These drugs could be either used alone (RI+/FAA-) or combined with drugs exhibiting folic acid antagonism (FAA, RI+/FAA+). The reference group included pregnant women who did not receive any RI-inducing drugs or FAA drugs. We analyzed 4116 exposed and 30 422 reference pregnancies. The hazard ratio (HR) with 95% confidence interval (CI) was 1.27 (95%CI 1.15-1.41) for pregnancies exposed to RI-inducing drugs as a whole. Considering subgroups of RI-inducing drugs, prenatal exposure to both RI+/FAA+ and RI+/FAA- was associated with the children's initiation of psychotropic medications, HRs being 1.35 (95%CI 1.10-1.66) and 1.26 (1.13-1.41), respectively. The HRs were increased with prolonged exposure to RI-inducing drugs, especially in the first and second trimesters. In a detailed examination of the psychotropics, the incidences of receiving antimigraine preparations and psychostimulants were significantly increased for the exposed children, compared with the reference children. The incidences of receiving antipsychotics and hypnotics were also higher for the exposed children; however, the HRs did not reach significance after adjustment. We found a significantly increased incident use of psychotropic medications among children prenatally exposed to RI-inducing drugs, especially during the first and second trimesters. This suggests a detrimental effect during critical periods of brain development. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Considerations on the medico-legal compensation for stochastic effects induced by the exposure to ionizing radiations in working environment

    International Nuclear Information System (INIS)

    Lafontaine, M.

    1988-01-01

    A better detection of stochastic diseases induced by the exposure to ionizing radiations and the establishment of causative correlation are presently reasons to justify new medico-legal approaches. The right to reparation for workers suffering from diseases which may have been caused by occupational exposure to ionizing radiations in Belgium, is covered by the law on occupational diseases and by the legislation on industrial accidents. However, some difficulties persist, concerning the right for compensation, consisting in the very short delay for prescription, the existence of an administrative list of diseases eligible for compensation and in the burden of proof to establish an obvious etiological relation. (Author)

  15. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Energy Technology Data Exchange (ETDEWEB)

    Zago, A. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Leão, R.M.; Carneiro-de-Oliveira, P.E. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil); Marin, M.T.; Cruz, F.C. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Planeta, C.S. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil)

    2011-11-18

    Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  16. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    International Nuclear Information System (INIS)

    Zago, A.; Leão, R.M.; Carneiro-de-Oliveira, P.E.; Marin, M.T.; Cruz, F.C.; Planeta, C.S.

    2011-01-01

    Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats

  17. Exposure to power frequency magnetic fields suppresses X-ray-induced apoptosis transiently in Ku80-deficient xrs5 cells

    International Nuclear Information System (INIS)

    Tian, Furong; Nakahara, Takehisa; Yoshida, Masami; Honda, Naoko; Hirose, Hideki; Miyakoshi, Junji

    2002-01-01

    In an attempt to determine whether exposure to extremely low frequency (ELF) electromagnetic fields can affect cells, Ku80-deficient cells (xrs5) and Ku80-proficient cells (CHO-K1) were exposed to ELF electromagnetic fields. Cell survival, and the levels of the apoptosis-related genes p21, p53, phospho-p53 (Ser 15 ), caspase-3 and the anti-apoptosis gene bcl-2 were determined in xrs5 and CHO-K1 cells following exposure to ELF electromagnetic fields and X-rays. It was found that exposure of xrs5 and CHO-K1 cells to 60 Hz ELF electromagnetic fields had no effect on cell survival, cell cycle distribution and protein expression. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields for 5 h after irradiation significantly inhibited G 1 cell cycle arrest induced by X-rays (1 Gy) and resulted in elevated bcl-2 expression. A significant decrease in the induction of p53, phospho-p53, caspase-3 and p21 proteins was observed in xrs5 cells when irradiation by X-rays (8 Gy) was followed by exposure to 5 mT ELF magnetic fields. Exposure of xrs5 cells to the ELF electromagnetic fields for 10 h following irradiation significantly decreased X-ray-induced apoptosis from about 1.7% to 0.7%. However, this effect was not found in CHO-K1 cells within 24 h of irradiation by X-rays alone and by X-rays combined with ELF electromagnetic fields. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields following irradiation can affect cell cycle distribution and transiently suppress apoptosis by decreasing the levels of caspase-3, p21, p53 and phospho-p53 and by increasing bcl-2 expression

  18. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Person, Rachel J.; Olive Ngalame, Ntube N.; Makia, Ngome L.; Bell, Matthew W.; Waalkes, Michael P.; Tokar, Erik J., E-mail: tokare@niehs.nih.gov

    2015-07-01

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  19. Vinclozolin exposure in utero induces postpubertal prostatitis and reduces sperm production via a reversible hormone-regulated mechanism.

    Science.gov (United States)

    Cowin, Prue A; Gold, Elspeth; Aleksova, Jasna; O'Bryan, Moira K; Foster, Paul M D; Scott, Hamish S; Risbridger, Gail P

    2010-02-01

    Vinclozolin is an endocrine-disrupting chemical (EDC) that binds with high affinity to the androgen receptor (AR) and blocks the action of gonadal hormones on male reproductive organs. An alternative mechanism of action of Vinclozolin involves transgenerational effects on the male reproductive tract. We previously reported in utero Vinclozolin exposure-induced prostatitis (prostate inflammation) in postpubertal rats concurrent with down-regulation of AR and increased nuclear factor-kappaB activation. We postulated the male reproductive abnormalities induced by in utero Vinclozolin exposure could be reversed by testosterone supplementation, in contrast to the permanent modifications involving DNA methyltransferases (Dnmts) described by others. To test this hypothesis, we administered high-dose testosterone at puberty to Vinclozolin-treated rats and determined the effect on anogenital distance (AGD); testicular germ cell apoptosis, concentration of elongated spermatids, and the onset of prostatitis. Concurrently we examined Dnmt1, -3A, -3B, and -3L mRNA expression. Consistent with previous reports, in utero exposure to Vinclozolin significantly reduced AGD, increased testicular germ cell apoptosis 3-fold, reduced elongated spermatid number by 40%, and induced postpubertal prostatitis in 100% of exposed males. Administration of high-dose testosterone (25 mg/kg) at puberty normalized AGD, reduced germ cell apoptosis, and restored elongated spermatid number. Testosterone restored AR and nuclear factor-kappaB expression in the prostate and abolished Vinclozolin-induced prostatitis. Altered Dnmt expression was evident with in utero Vinclozolin exposure and was not normalized after testosterone treatment. These data demonstrate in utero Vinclozolin-induced male reproductive tract abnormalities are AR mediated and reversible and involve a mechanism independent of Dnmt expression.

  20. Sunlight Triggers Cutaneous Lupus through a Colony Stimulating Factor-1 (CSF-1) Dependent Mechanism in MRL-Faslpr mice

    Science.gov (United States)

    Menke, Julia; Hsu, Mei-Yu; Byrne, Katelyn T.; Lucas, Julie A.; Rabacal, Whitney A.; Croker, Byron P.; Zong, Xiao-Hua; Stanley, E. Richard; Kelley, Vicki R.

    2008-01-01

    Sunlight (UVB) triggers cutaneous (CLE) and systemic lupus through an unknown mechanism. We tested the hypothesis that UVB triggers CLE through a CSF-1-dependent, macrophage (Mø) -mediated mechanism in MRL-Faslpr mice. By constructing mutant MRL-Faslpr strains expressing varying levels of CSF-1 (high, intermediate, none), and use of an ex-vivo gene transfer to deliver CSF-1 intra-dermally, we determined that CSF-1 induces CLE in lupus-susceptible, MRL-Faslpr mice, but not in lupus-resistant, BALB/c mice. Notably, UVB incites an increase in Mø, apoptosis in the skin and CLE in MRL-Faslpr, but not in CSF-1-deficient MRL-Faslpr mice. Furthermore, UVB did not induce CLE in BALB/c mice. Probing further, UVB stimulates CSF-1 expression by keratinocytes leading to recruitment and activation of Mø that, in turn, release mediators, which induce apoptosis in keratinocytes. Thus, sunlight triggers a CSF-1-dependent, Mø-mediated destructive inflammation in the skin leading to CLE in lupus-susceptible MRL-Faslpr, but not lupus-resistant BALB/c mice. Taken together, we envision CSF-1 as the “match” and lupus-susceptibility as the “tinder” leading to CLE. PMID:18981160

  1. PFOS prenatal exposure induce mitochondrial injury and gene expression change in hearts of weaned SD rats

    International Nuclear Information System (INIS)

    Xia, Wei; Wan, Yanjian; Li, Yuan-yuan; Zeng, Huaicai; Lv, Ziquan; Li, Gengqi; Wei, Zhengzheng; Xu, Shun-qing

    2011-01-01

    heart function. The results indicate PFOS prenatal exposure can induce cardiac mitochondrial injury and gene transcript change, which may be a significant mechanism of the developmental toxicity of PFOS to rat.

  2. Recurrent exposure to subclinical lipopolysaccharide increases mortality and induces cardiac fibrosis in mice.

    Directory of Open Access Journals (Sweden)

    Wilbur Y W Lew

    Full Text Available BACKGROUND: Circulating subclinical lipopolysaccharide (LPS occurs in health and disease. Ingesting high fatty meals increases LPS that cause metabolic endotoxemia. Subclinical LPS in periodontal disease may impair endothelial function. The heart may be targeted as cardiac cells express TLR4, the LPS receptor. It was hypothesized that recurrent exposure to subclinical LPS increases mortality and causes cardiac fibrosis. METHODS: C57Bl/6 mice were injected with intraperitoneal saline (control, low dose LPS (0.1 or 1 mg/kg, or moderate dose LPS (10 or 20 mg/kg, once a week for 3 months. Left ventricular (LV function (echocardiography, hemodynamics (tail cuff pressure and electrocardiograms (telemetry were measured. Cardiac fibrosis was assessed by picrosirius red staining and LV expression of fibrosis related genes (QRT-PCR. Adult cardiac fibroblasts were isolated and exposed to LPS. RESULTS: LPS injections transiently increased heart rate and blood pressure (<6 hours and mildly decreased LV function with full recovery by 24 hours. Mice tolerated weekly LPS for 2-3 months with no change in activity, appearance, appetite, weight, blood pressure, LV function, oximetry, or blood chemistries. Mortality increased after 60-90 days with moderate, but not low dose LPS. Arrhythmias occurred a few hours before death. LV collagen fraction area increased dose-dependently from 3.0±0.5% (SEM in the saline control group, to 5.6±0.5% with low dose LPS and 9.7±0.9% with moderate dose LPS (P<0.05 moderate vs low dose LPS, and each LPS dose vs control. LPS increased LV expression of collagen Iα1, collagen IIIα1, MMP2, MMP9, TIMP1, periostin and IL-6 (P<0.05 moderate vs low dose LPS and vs control. LPS increased α-SMA immunostaining of myofibroblasts. LPS dose-dependently increased IL-6 in isolated adult cardiac fibroblasts. CONCLUSIONS: Recurrent exposure to subclinical LPS increases mortality and induces cardiac fibrosis.

  3. Repeated exposure to Lutzomyia intermedia sand fly saliva induces local expression of interferon-inducible genes both at the site of injection in mice and in human blood.

    Science.gov (United States)

    Weinkopff, Tiffany; de Oliveira, Camila I; de Carvalho, Augusto M; Hauyon-La Torre, Yazmin; Muniz, Aline C; Miranda, Jose Carlos; Barral, Aldina; Tacchini-Cottier, Fabienne

    2014-01-01

    During a blood meal, Lutzomyia intermedia sand flies transmit Leishmania braziliensis, a parasite causing tegumentary leishmaniasis. In experimental leishmaniasis, pre-exposure to saliva of most blood-feeding sand flies results in parasite establishment in absence of any skin damages in mice challenged with dermotropic Leishmania species together with saliva. In contrast, pre-immunization with Lu. intermedia salivary gland sonicate (SGS) results in enhanced skin inflammatory exacerbation upon co-inoculation of Lu. intermedia SGS and L. braziliensis. These data highlight potential unique features of both L. braziliensis and Lu. intermedia. In this study, we investigated the genes modulated by Lu. intermedia SGS immunization to understand their potential impact on the subsequent cutaneous immune response following inoculation of both SGS and L. braziliensis. The cellular recruitment and global gene expression profile was analyzed in mice repeatedly inoculated or not with Lu. intermedia. Microarray gene analysis revealed the upregulation of a distinct set of IFN-inducible genes, an immune signature not seen to the same extent in control animals. Of note this INF-inducible gene set was not induced in SGS pre-immunized mice subsequently co-inoculated with SGS and L. braziliensis. These data suggest the parasite prevented the upregulation of this Lu. intermedia saliva-related immune signature. The presence of these IFN-inducible genes was further analyzed in peripheral blood mononuclear cells (PBMCs) sampled from uninfected human individuals living in a L. braziliensis-endemic region of Brazil thus regularly exposed to Lu. intermedia bites. PBMCs were cultured in presence or absence of Lu. intermedia SGS. Using qRT-PCR we established that the IFN-inducible genes induced in the skin of SGS pre-immunized mice, were also upregulated by SGS in PBMCs from human individuals regularly exposed to Lu. intermedia bites, but not in PBMCs of control subjects. These data demonstrate

  4. Unintentional exposure to ultraviolet radiation

    International Nuclear Information System (INIS)

    Sliney, D.H.

    1987-01-01

    To evaluate the risks from unintentional exposure to ultraviolet radiation (UVR), and to consider hazard control regulation, one must face first the problem of their state of scientific knowledge and the public's perception of UVR. Few people in the general public would question the health benefits of sunlight. Many flock to the beaches each summer to develop a healthy tan. Since the 1920's scientists have recognized that most of the benefits--and risks--of sunlight exposure result from the UVR present in sunlight. Dermatologists warn sunbathers to avoid exposure or protect themselves against the intense midday UVR or risk skin cancer. A growing number of scientists warn of hazards to the eye if UVR--perhaps even shorter visible wavelengths--are not filtered by lenses. In addition to any intentional exposure for health or cosmetic purposes, many people are also exposed to UVR without being aware of it or without their intent to be exposed. Outdoor workers are exposed to sunlight, many industrial workers (e.g., welders) are exposed to UVR from arc sources, some UVR penetrates clothing, and people indoors are exposed to UVR from artificial lighting

  5. Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats.

    Science.gov (United States)

    Domingues, Alexandre; Barbisan, Luis Fernando; Martins, Priscila Raquel; Spinardi-Barbisan, Ana Lúcia Tozzi

    2011-05-01

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substitute urea herbicide widely used on agricultural crops with potential mutagenic, teratogenic, reproductive and carcinogenic effects. Nonetheless, its toxic potential on the immune system needs a detailed assessment. Thus, in order to evaluate the adverse effect of this herbicide on lymphohematopoietic organs and macrophage activity, male Wistar rats were orally treated with Diuron at 125, 1250 and 2500 ppm for 14, 28 or 90 days. General signs of toxicity were observed in Diuron-treated groups (1250 and 2500 ppm), including reduced food intake and body weight gain, as well as higher relative weights for spleen, kidneys and liver (28 and 90-day toxicity studies) and elevated serum levels of ALT, albumin, total protein, creatinine and urea (28-day toxicity study). Diuron exposure caused a severe depletion of splenic white pulp compartments and cellularity, followed by a decreased number of CD4(+) T lymphocytes, increased extramedullary hematopoiesis and deposition of hemosiderin in red pulp. Despite alteration in macrophage spreading, the macrophagic activity was not significantly affected by the herbicide. Under these experimental conditions, the results suggest that Diuron exerts systemic and target-organ toxicity, mainly at higher concentration. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Prenatal caffeine exposure induced a lower level of fetal blood leptin mainly via placental mechanism

    International Nuclear Information System (INIS)

    Wu, Yi-meng; Luo, Han-wen; Kou, Hao; Wen, Yin-xian; Shen, Lang; Pei, Ling-guo; Zhou, Jin; Zhang, Yuan-zhen; Wang, Hui

    2015-01-01

    It's known that blood leptin level is reduced in intrauterine growth retardation (IUGR) fetus, and placental leptin is the major source of fetal blood leptin. This study aimed to investigate the decreased fetal blood leptin level by prenatal caffeine exposure (PCE) and its underlying placental mechanisms. Pregnant Wistar rats were intragastrically administered caffeine (30–120 mg/kg day) from gestational day 9 to 20. The level of fetal serum leptin and the expression of placental leptin-related genes were analyzed. Furthermore, we investigated the molecular mechanism of the reduced placental leptin's expression by treatment with caffeine (0.8–20 μM) in the BeWo cells. In vivo, PCE significantly decreased fetal serum leptin level in caffeine dose-dependent manner. Meanwhile, placental mRNA expression of adenosine A2a receptor (Adora2a), cAMP-response element binding protein (CREB), a short-type leptin receptor (Ob-Ra) and leptin was reduced in the PCE groups. In vitro, caffeine significantly decreased the mRNA expression of leptin, CREB and ADORA2A in concentration and time-dependent manners. The addition of ADORA2A agonist or adenylyl cyclase (AC) agonist reversed the inhibition of leptin expression induced by caffeine. PCE induced a lower level of fetal blood leptin, which the primary mechanism is that caffeine inhibited antagonized Adora2a and AC activities to decreased cAMP synthesis, thus inhibited the expression of the transcription factor CREB and target gene leptin in the placenta. Meantime, the reduced transportation of maternal leptin by placental Ob-Ra also contributed to the reduced fetal blood leptin. Together, PCE decreased fetal blood leptin mainly via reducing the expression and transportation of leptin in the placenta. - Highlights: • Caffeine reduced fetal blood leptin level. • Caffeine inhibited placental leptin production and transport. • Caffeine down-regulated placental leptin expression via antagonizing ADORA2.

  7. Prenatal caffeine exposure induced a lower level of fetal blood leptin mainly via placental mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yi-meng [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Luo, Han-wen [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Kou, Hao [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Wen, Yin-xian [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Shen, Lang; Pei, Ling-guo; Zhou, Jin [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Zhang, Yuan-zhen [Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan 430071 (China); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan 430071 (China)

    2015-11-15

    It's known that blood leptin level is reduced in intrauterine growth retardation (IUGR) fetus, and placental leptin is the major source of fetal blood leptin. This study aimed to investigate the decreased fetal blood leptin level by prenatal caffeine exposure (PCE) and its underlying placental mechanisms. Pregnant Wistar rats were intragastrically administered caffeine (30–120 mg/kg day) from gestational day 9 to 20. The level of fetal serum leptin and the expression of placental leptin-related genes were analyzed. Furthermore, we investigated the molecular mechanism of the reduced placental leptin's expression by treatment with caffeine (0.8–20 μM) in the BeWo cells. In vivo, PCE significantly decreased fetal serum leptin level in caffeine dose-dependent manner. Meanwhile, placental mRNA expression of adenosine A2a receptor (Adora2a), cAMP-response element binding protein (CREB), a short-type leptin receptor (Ob-Ra) and leptin was reduced in the PCE groups. In vitro, caffeine significantly decreased the mRNA expression of leptin, CREB and ADORA2A in concentration and time-dependent manners. The addition of ADORA2A agonist or adenylyl cyclase (AC) agonist reversed the inhibition of leptin expression induced by caffeine. PCE induced a lower level of fetal blood leptin, which the primary mechanism is that caffeine inhibited antagonized Adora2a and AC activities to decreased cAMP synthesis, thus inhibited the expression of the transcription factor CREB and target gene leptin in the placenta. Meantime, the reduced transportation of maternal leptin by placental Ob-Ra also contributed to the reduced fetal blood leptin. Together, PCE decreased fetal blood leptin mainly via reducing the expression and transportation of leptin in the placenta. - Highlights: • Caffeine reduced fetal blood leptin level. • Caffeine inhibited placental leptin production and transport. • Caffeine down-regulated placental leptin expression via antagonizing ADORA2.

  8. Cardio protective role of garlic (Allium Sativum) against oxidative stress induced by gamma radiation exposure

    International Nuclear Information System (INIS)

    Said, U.Z.; Azab, KH.SH.; And Soliman, A.M.

    2004-01-01

    Oxidative stress and free radicals play a crucial role in the pathophysiology of a broad spectrum of cardiovascular diseases. The need to identify agents with a potential for preventing such damage has assumed great importance. Therefore, the present study was designed to investigate the possible effect of raw garlic homogenate on cardiac endogenous antioxidants, lipid peroxidation and histopathological changes. Plasma lipid profile was also determined. Three different dosage levels (125, 250 and 500 mg/kg body weight) once daily for 20 days were evaluated. The results obtained showed that whole body gamma irradiation of rats at 6 Gy (single dose) resulted in significant increase in cardiac thiobarbituric acid reactive substances (TEARS) along with reduction in cardiac superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) activities 1, 2 and 4 weeks following radiation exposure. These changes were associated with subendocardial loss of muscles and accumulation of acute inflammatory cells surrounded by edema. Depletion of cardiac endogenous antioxidants and rise in TEARS were significantly less in the garlic treated rats. Also, histological examination of cardiac tissue showed less damage. Garlic treatment significantly diminished the radiation induced increase in the plasma content of triglycerides, total cholesterol and low density lipoprotein-cholesterol (LDL-C). Significant amelioration was also observed in the plasma content of high density lipoprotein- cholesterol (HDL-C) as compared to irradiated rats. Among the three garlic treated groups, 250 mg/kg group showed the best protection in terms of biochemical and histopathological evidences. It could be concluded that the intake dose plays an important role on endogenous antioxidants and cytoprotective effects on the heart

  9. Ribavirin exposure induces histopathological changes in the seminiferous tubules of testes in albino rats

    International Nuclear Information System (INIS)

    Batool, A.

    2013-01-01

    Study objectives: The objectives of the study are to describe and compare histopathological changes in the seminiferous tubules of testes of rat, with different doses of Ribavirin at different time intervals. Introduction: The chemical disturbances may affect a vast number of potential sites in male reproductive system as well as its complex hormonal regulation. Testicular toxicity may reduce the fertility of the male. The current study was conducted to evaluate the effects of Ribavirin on the histological structure of seminiferous tubules in the testes of albino rats. Materials and Methods: Seventy two sexually mature adult male albino rats weighing 180-200gms were divided into four groups: A, B, C and D; each group having 18 rats. Ribavirin was administered intraperitoneally in different doses to these groups that were 20mg, 100mg and 200mg/kg body weight, while group A was control. Each group was further divided into three subgroups according to three time points which were selected for sacrifice that were 20th, 40th and 60th day from the last exposure to drug. Six randomly selected rats from each group were sacrificed on every sacrifice time. Results and Conclusion: The seminiferous tubules with degenerative changes like appearance of vacuole and necrotic material were observed in comparison to control groups, on 20th day of sacrifice in all groups. In rats sacrificed on day 40th and 60th, the sign of recovery in the form of regeneration of seminiferous epithelium was observed that was more marked in low dose groups than high dose groups which showed late recovery. We conclude that ribavirin being used as antiviral drug induces reversible degenerative changes in the seminiferous tubules of testes of albino rats. (author)

  10. Neonatal bee venom exposure induces sensory modality-specific enhancement of nociceptive response in adult rats.

    Science.gov (United States)

    Li, Mengmeng; Chen, Huisheng; Tang, Jiaguang; Chen, Jun

    2014-06-01

    Previous studies have shown that inflammatory pain at the neonatal stage can produce long-term structural and functional changes in nociceptive pathways, resulting in altered pain perception in adulthood. However, the exact pattern of altered nociceptive response and associated neurochemical changes in the spinal cord in this process is unclear. In this study, we used an experimental paradigm in which each rat first received intraplantar bee venom (BV) or saline injection on postnatal day 1, 4, 7, 14, 21, or 28. This was followed 2 months later by a second intraplantar bee venom injection in the same rats to examine the difference in nociceptive responses. We found that neonatal inflammatory pain induced by the first BV injection significantly reduced baseline paw withdrawal mechanical threshold, but not baseline paw withdrawal thermal latency, when rats were examined 2 months from the first BV injection. Neonatal inflammatory pain also exacerbated mechanical, but not thermal, hyperalgesia in response to the second BV injection in these same rats. Rats exposed to neonatal inflammation also showed up-regulation of spinal NGF, TrkA receptor, BDNF, TrkB receptor, IL-1β, and COX-2 expression following the second BV injection, especially with prior BV exposure on postnatal day 21 or 28. These results indicate that neonatal inflammation produces sensory modality-specific changes in nociceptive behavior and alters neurochemistry in the spinal cord of adult rats. These results also suggest that a prior history of inflammatory pain during the developmental period might have an impact on clinical pain in highly susceptible adult patients. Wiley Periodicals, Inc.

  11. Bisphenol A induces steatosis in HepaRG cells using a model of perinatal exposure

    OpenAIRE

    Bucher , Simon; Jalili , Pégah; Le Guillou , Dounia; Begriche , Karima; Rondel , Karine; Martinais , Sophie; Zalko , Daniel; Corlu , Anne; Robin , Marie-Anne; Fromenty , Bernard

    2017-01-01

    International audience; Human exposure to bisphenol A (BPA) could favor obesity and related metabolic disorders such as hepatic steatosis. Investigations in rodents have shown that these deleterious effects are observed not only when BPA is administered during the adult life but also with different protocols of perinatal exposure. Whether perinatal BPA exposure could pose a risk in human is currently unknown, and thus appropriate in vitro models could be important to tackle this major issue. ...

  12. Is beryllium-induced lung cancer caused only by soluble forms and high exposure levels?

    Science.gov (United States)

    Schubauer-Berigan, Mary K; Couch, James R; Deddens, James A

    2017-08-01

    The US Occupational Safety and Health Administration (OSHA) recently proposed a permissible exposure limit of 0.2 µg/m 3 for beryllium, based partly on extrapolated estimates of lung cancer risk from a pooled occupational cohort. The purpose of the present analysis was to evaluate whether cohort members exposed at lower levels to mainly insoluble forms of beryllium exhibit increased risk of lung cancer. We conducted Cox proportional hazards regression analyses among 75 lung cancer cases in age-based risk sets within two lower exposure plants in the pooled cohort followed from 1940 to 2005. We used categorical and power models to evaluate exposure-response patterns for mean and cumulative beryllium exposures in the two-plant cohort, comparing findings with the full pooled cohort. We also evaluated the distribution of exposure-years in each cohort by solubility class (soluble, insoluble and mixed). 98% of workers in the two-plant cohort were hired between 1955 and 1969. The mean beryllium exposure averaged 1.3 µg/m 3 and the predominant form was insoluble. Adjusting for confounders, we observed a monotonic increase in lung cancer mortality across exposure categories in the two-plant cohort. The exposure-response coefficients (per unit ln exposure) were 0.270 (p=0.061) for mean exposure and 0.170 (p=0.033) for cumulative exposure, compared with 0.155 and 0.094 (respectively) in the full cohort. The low-exposure levels at these two plants and the predominance of insoluble beryllium suggest that the overall pooled cohort findings on which OSHA's lung cancer risk assessment is based are relevant for current workers exposed to any form of beryllium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Genotoxic effects induced by the exposure to an environmental mixture of illicit drugs to the zebra mussel.

    Science.gov (United States)

    Parolini, Marco; Magni, Stefano; Castiglioni, Sara; Binelli, Andrea

    2016-10-01

    Despite the growing interest on the presence of illicit drugs in freshwater ecosystems, just recently the attention has been focused on their potential toxicity towards non-target aquatic species. However, these studies largely neglected the effects induced by exposure to complex mixtures of illicit drugs, which could be different compared to those caused by single psychoactive molecules. This study was aimed at investigating the genetic damage induced by a 14-day exposure to a realistic mixture of the most common illicit drugs found in surface waters worldwide (cocaine, benzoylecgonine, amphetamine, morphine and 3,4-methylenedioxymethamphetamine) on the zebra mussel (Dreissena polymorpha). The mixture caused a significant increase of DNA fragmentation and triggered the apoptotic process and micronuclei formation in zebra mussel hemocytes, pointing out its potential genotoxicity towards this bivalve species. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. In utero exposure to nanosized carbon black (Printex90) does not induce tandem repeat mutations in female murine germ cells

    DEFF Research Database (Denmark)

    Boisen, Anne Mette Zenner; Shipley, Thomas; Jackson, Petra

    2013-01-01

    Inhalation of particles has been shown to induce mutations in the male germline in mice following both prenatal and adult exposures in several experiments. In contrast, the effects of particles on female germ cell mutagenesis are not well established. Germline mutations are induced during active...... cell division, which occurs during fetal development in females. We investigated the effects of prenatal exposure to carbon black nanoparticles (CB) on induction of mutations in the female mouse germline during fetal development, spanning the critical developmental stages of oogenesis. Pregnant C57BL/6...... mutation rates in the resulting F2 generation were determined from full pedigrees (mother, father, offspring) of F1 female mice (178 CB-exposed and 258 control F2 offspring). ESTR mutation rates in CB-exposed F2 female offspring were not statistically different from those of F2 female control offspring....

  15. Asteroid thermal modeling in the presence of reflected sunlight

    Science.gov (United States)

    Myhrvold, Nathan

    2018-03-01

    A new derivation of simple asteroid thermal models is presented, investigating the need to account correctly for Kirchhoff's law of thermal radiation when IR observations contain substantial reflected sunlight. The framework applies to both the NEATM and related thermal models. A new parameterization of these models eliminates the dependence of thermal modeling on visible absolute magnitude H, which is not always available. Monte Carlo simulations are used to assess the potential impact of violating Kirchhoff's law on estimates of physical parameters such as diameter and IR albedo, with an emphasis on NEOWISE results. The NEOWISE papers use ten different models, applied to 12 different combinations of WISE data bands, in 47 different combinations. The most prevalent combinations are simulated and the accuracy of diameter estimates is found to be depend critically on the model and data band combination. In the best case of full thermal modeling of all four band the errors in an idealized model the 1σ (68.27%) confidence interval is -5% to +6%, but this combination is just 1.9% of NEOWISE results. Other combinations representing 42% of the NEOWISE results have about twice the CI at -10% to +12%, before accounting for errors due to irregular shape or other real world effects that are not simulated. The model and data band combinations found for the majority of NEOWISE results have much larger systematic and random errors. Kirchhoff's law violation by NEOWISE models leads to errors in estimation accuracy that are strongest for asteroids with W1, W2 band emissivity ɛ12 in both the lowest (0.605 ≤ɛ12 ≤ 0 . 780), and highest decile (0.969 ≤ɛ12 ≤ 0 . 988), corresponding to the highest and lowest deciles of near-IR albedo pIR. Systematic accuracy error between deciles ranges from a low of 5% to as much as 45%, and there are also differences in the random errors. Kirchhoff's law effects also produce large errors in NEOWISE estimates of pIR, particularly for high

  16. Induction by mercury compounds of brain metallothionein in rats: Hg{sup 0} exposure induces long-lived brain metallothionein

    Energy Technology Data Exchange (ETDEWEB)

    Yasutake, Akira; Nakano, Atsuhiro [Biochemistry Section, National Institute for Minamata Disease, Kumamoto (Japan); Hirayama, Kimiko [Kumamoto University, College of Medical Science (Japan)

    1998-03-01

    Metallothionein (MT) is one of the stress proteins which can easily be induced by various kind of heavy metals. However, MT in the brain is difficult to induce because of blood-brain barrier impermeability to most heavy metals. In this paper, we have attempted to induce brain MT in rats by exposure to methylmercury (MeHg) or metallic mercury vapor, both of which are known to penetrate the blood-brain barrier and cause neurological damage. Rats treated with MeHg (40 {mu}mol/kg per day x 5 days, p.o.) showed brain Hg levels as high as 18 {mu}g/g with slight neurological signs 10 days after final administration, but brain MT levels remained unchanged. However, rats exposed to Hg vapor for 7 days showed 7-8 {mu}g Hg/g brain tissue 24 h after cessation of exposure. At that time brain MT levels were about twice the control levels. Although brain Hg levels fell gradually with a half-life of 26 days, MT levels induced by Hg exposure remained unchanged for >2 weeks. Gel fractionation revealed that most Hg was in the brain cytosol fraction and thus bound to MT. Hybridization analysis showed that, despite a significant increase in MT-I and -II mRNA in brain, MT-III mRNA was less affected. Although significant Hg accumulation and MT induction were observed also in kidney and liver of Hg vapor-exposed rats, these decreased more quickly than in brain. The long-lived MT in brain might at least partly be accounted for by longer half-life of Hg accumulated there. The present results showed that exposure to Hg vapor might be a suitable procedure to provide an in vivo model with enhanced brain MT. (orig.) With 4 figs., 1 tab., 27 refs.

  17. Vinclozolin Exposure in Utero Induces Postpubertal Prostatitis and Reduces Sperm Production via a Reversible Hormone-Regulated Mechanism

    OpenAIRE

    Cowin, Prue A.; Gold, Elspeth; Aleksova, Jasna; O'Bryan, Moira K.; Foster, Paul M. D.; Scott, Hamish S.; Risbridger, Gail P.

    2010-01-01

    Vinclozolin is an endocrine-disrupting chemical (EDC) that binds with high affinity to the androgen receptor (AR) and blocks the action of gonadal hormones on male reproductive organs. An alternative mechanism of action of Vinclozolin involves transgenerational effects on the male reproductive tract. We previously reported in utero Vinclozolin exposure-induced prostatitis (prostate inflammation) in postpubertal rats concurrent with down-regulation of AR and increased nuclear factor-κB activat...

  18. BaP-metals co-exposure induced tissue-specific antioxidant defense in marine mussels Mytilus coruscus.

    Science.gov (United States)

    Chen, Siyu; Qu, Mengjie; Ding, Jiawei; Zhang, Yifei; Wang, Yi; Di, Yanan

    2018-04-18

    Both benzo(α)pyrene (BaP) and metals are frequently found in marine ecosystem and can cause detrimental effects in marine organism, especially the filter feeder-marine mussels. Although the biological responses in mussels have been well-studied upon the single metal or BaP exposure, the information about antioxidant defense, especially in different tissues of mussels, are still limited. Considering the variety of contaminants existing in the actual marine environment, single BaP (56 μg/L) and the co-exposure with Cu, Cd and Pb (50 μg/L, 50 μg/L and 3 mg/L respectively) were applied in a 6 days exposure followed by 6 days depuration experiment. The alterations of superoxide dismutase (SOD), catalase (CAT) activities and total antioxidant capacity (TAC) level were assessed in haemolymph, gills and digestive glands of marine mussels, Mytilus coruscus. An unparalleled change in antioxidant biomarkers was observed in all cells/tissues, with the SOD activity showing higher sensitivity to exposure. A tissue-specific response showing unique alteration in gill was investigated, indicating the different function of tissues during stress responses. Depressed antioxidant effects were induced by BaP-metals co-exposure, indicating the interaction may alter the intact properties of BaP. To our knowledge, this is the first research to explore the antioxidant defense induced by combined exposure of BaP-metals regarding to tissue-specific responses in marine mussels. The results and experimental model will provide valuable information and can be utilized in the investigation of stress response mechanisms, especially in relation to tissue functions in marine organism in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Influence of turmeric on biochemical disorders induced by exposure to gamma- rays or chloropyrifos pesticide on rats

    International Nuclear Information System (INIS)

    Kamal El-Dein, E.M.; Ebrahim, R.M.

    2013-01-01

    Toxicity of Chloropyrifos and gamma-radiation exposure on rats were examined in the presence or absence of Turmeric (200 mg/ kg/ b.wt.). Effects chloropyrifos when administrated orally to rats at a dose 9 mg/ kg b .wt (1/ 4 LD 50) for 7 and 28 days showed increased level of malondialdehyde (MDA) concomitant with depletion in the levels of glutathion (GSH), superoxide dismutase (SOD) and catalase (CAT).gamma- radiation exposure effect on rats was examined in the presence or absence of turmeric . Exposure of rats to gamma-radiation (8 Gy) at a fractionated dose levels (2 Gy/ week for 4 weeks) exhibited an elevated level of MDA and decreased level of GSH, SOD and CAT. Administration of Turmeric to animals which were previously treated with Chloropyrifos or gamma-rays showed an amelioration response to the antioxidant regime. Treatment of rats with Chloropyrifos for 7 and 28 days or gamma- radiation induced an elevated serum transaminases level(ALT and AST),Alkaline phosphatase (ALP) and Acid phosphatase activity (ACP), creatinine concentration, blood urea and uric acid.Also treatment of rats with Chloropyrifos for 7 and 28 days or gamma-radiation induced a decline in the testosterone level associated with alteration in the levels of follicular stimulating hormone (FSH),Iuetinizing hormone (LH) and prolactin (PRL).Results observed due to Chloropyrifos pesticide or radiation-exposure have been ameliorated by turmeric administration. It could be concluded that turmeric might protect from oxidative stress

  20. Polychlorinated biphenyls pattern analysis: Potential nondestructive biomarker in vertebrates for exposure to cytochrome P450-inducing organochlorines

    Energy Technology Data Exchange (ETDEWEB)

    Brink, N.W. van den; Ruiter-Dijkman, E.M. De; Broekhuizen, S.; Reijnders, P.J.H.; Bosveld, A.T.C.

    2000-03-01

    Biomarkers are valuable instruments to assess the risks from exposure of organisms to organochlorines. In general, however, these biomarkers are either destructive to the animal of interest or extremely difficult to obtain otherwise. In this paper, the authors present a nondestructive biomarker for exposure to cytochrome P450-inducing organochlorines. This marker is based on a pattern analysis of metabolizable and nonmetabolizable polychlorinated biphenyl (PCB) congeners, which occur in several kinds of tissues (and even blood) that can be obtained without serious effects on the organism involved. The fraction of metabolizable PCB congeners is negatively correlated with exposure to PCBs, which are known to induce specific P450 isoenzymes. This relation can be modeled by a logistic curve, which can be used to define critical levels of exposure. In addition, this method creates an opportunity to analyze biomarker responses in archived tissues stored at standard freezing temperatures ({minus}20 C), at which responses to established biomarkers deteriorate. Furthermore, this method facilitates attribution of the enzyme induction to certain classes of compounds.

  1. Simultaneous detection of ultraviolet B-induced DNA damage using capillary electrophoresis with laser-induced fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Guthrie, Jeffrey W., E-mail: jeff.guthrie@emich.edu; Limmer, Robert T.; Brooks, Eric A.; Wisnewski, Chelsea C.; Loggins-Davis, Nnekia D.; Bouzid, Abderraouf

    2015-01-01

    Highlights: • CE–LIF was developed for simultaneous detection of UV-induced DNA photoproducts. • Fluorescent quantum dot reporters enabled detection of small amounts of photoproducts. • Photoproducts were detected after 65 J m{sup −2} of fluence from a UVB lamp in ∼6 ng of DNA. • Natural sunlight induced cyclobutane pyrimidine dimers after only 15 min of exposure. - Abstract: An immunoassay based on CE–LIF was developed for the simultaneous detection of cyclobutane pyrimidine dimers (CPDs) and pyrimidine 6-4 pyrimidone photoproducts (6-4PPs) in genomic DNA irradiated with UVB or natural sunlight. Human cells were first exposed to varying amounts of UVB or natural sunlight to induce DNA damage. Genomic DNA was extracted and incubated with anti-CPD and anti-6-4PP primary antibodies attached to secondary antibodies with a fluorescent quantum dot (QD) reporter that emitted either red or yellow fluorescence. CE was used to separate the unbound antibodies from those bound to the photoproducts, and LIF with appropriate optical filters was used to separate the fluorescence signals from each QD to individual photomultiplier tubes for simultaneous photoproduct detection. Using this strategy, photoproducts were detected from ∼6 ng (200 ng μL{sup −1}) of DNA under a low UVB fluence of 65 J m{sup −2} for CPDs or 195 J m{sup −2} for 6-4PPs. This assay was also the first to demonstrate the detection of CPDs in human cells after only 15 min of irradiation under natural sunlight.

  2. Simultaneous detection of ultraviolet B-induced DNA damage using capillary electrophoresis with laser-induced fluorescence

    International Nuclear Information System (INIS)

    Guthrie, Jeffrey W.; Limmer, Robert T.; Brooks, Eric A.; Wisnewski, Chelsea C.; Loggins-Davis, Nnekia D.; Bouzid, Abderraouf

    2015-01-01

    Highlights: • CE–LIF was developed for simultaneous detection of UV-induced DNA photoproducts. • Fluorescent quantum dot reporters enabled detection of small amounts of photoproducts. • Photoproducts were detected after 65 J m −2 of fluence from a UVB lamp in ∼6 ng of DNA. • Natural sunlight induced cyclobutane pyrimidine dimers after only 15 min of exposure. - Abstract: An immunoassay based on CE–LIF was developed for the simultaneous detection of cyclobutane pyrimidine dimers (CPDs) and pyrimidine 6-4 pyrimidone photoproducts (6-4PPs) in genomic DNA irradiated with UVB or natural sunlight. Human cells were first exposed to varying amounts of UVB or natural sunlight to induce DNA damage. Genomic DNA was extracted and incubated with anti-CPD and anti-6-4PP primary antibodies attached to secondary antibodies with a fluorescent quantum dot (QD) reporter that emitted either red or yellow fluorescence. CE was used to separate the unbound antibodies from those bound to the photoproducts, and LIF with appropriate optical filters was used to separate the fluorescence signals from each QD to individual photomultiplier tubes for simultaneous photoproduct detection. Using this strategy, photoproducts were detected from ∼6 ng (200 ng μL −1 ) of DNA under a low UVB fluence of 65 J m −2 for CPDs or 195 J m −2 for 6-4PPs. This assay was also the first to demonstrate the detection of CPDs in human cells after only 15 min of irradiation under natural sunlight

  3. Decreased extracellular adenosine levels lead to loss of hypoxia-induced neuroprotection after repeated episodes of exposure to hypoxia.

    Directory of Open Access Journals (Sweden)

    Mei Cui

    Full Text Available Achieving a prolonged neuroprotective state following transient ischemic attacks (TIAs is likely to effectively reduce the brain damage and neurological dysfunction associated with recurrent stroke. HPC is a phenomenon in which advanced exposure to mild hypoxia reduces the stroke volume produced by a subsequent TIA. However, this neuroprotection is not long-lasting, with the effects reaching a peak after 3 days. Therefore, in this study, we investigated the use of multiple episodes of hypoxic exposure at different time intervals to induce longer-term protection in a mouse stroke model. C57BL/6 mice were subjected to different hypoxic preconditioning protocols: a single episode of HPC or five identical episodes at intervals of 3 days (E3d HPC or 6 days (E6d HPC. Three days after the last hypoxic exposure, temporary middle cerebral artery occlusion (MCAO was induced. The effects of these HPC protocols on hypoxia-inducible factor (HIF regulated gene mRNA expression were measured by quantitative PCR. Changes in extracellular adenosine concentrations, known to exert neuroprotective effects, were also measured using in vivo microdialysis and high pressure liquid chromatography (HPLC. Neuroprotection was provided by E6d HPC but not E3d HPC. HIF-regulated target gene expression increased significantly following all HPC protocols. However, E3d HPC significantly decreased extracellular adenosine and reduced cerebral blood flow in the ischemic region with upregulated expression of the adenosine transporter, equilibrative nucleoside transporter 1 (ENT1. An ENT1 inhibitor, propentofylline increased the cerebral blood flow and re-established neuroprotection in E3d HPC. Adenosine receptor specific antagonists showed that adenosine mainly through A1 receptor mediates HPC induced neuroprotection. Our data indicate that cooperation of HIF-regulated genes and extracellular adenosine is necessary for HPC-induced neuroprotection.

  4. Mitochondrial damage: An important mechanism of ambient PM2.5 exposure-induced acute heart injury in rats

    International Nuclear Information System (INIS)

    Li, Ruijin; Kou, Xiaojing; Geng, Hong; Xie, Jingfang; Tian, Jingjing; Cai, Zongwei; Dong, Chuan

    2015-01-01

    Highlights: • PM 2.5 induces heart mitochondrial morphological damage of rats. • Mitochondrial fission/fusion gene expression is important regulation mechanism. • Proinflammatoy cytokine level changes are accompanied with mitochondrial damage. • Alterations in oxidative stress and calcium homeostasis are focused on. - Abstract: Epidemiological studies suggested that ambient fine particulate matter (PM 2.5 ) exposure was associated with cardiovascular disease. However, the underlying mechanism, especially the mitochondrial damage mechanism, of PM 2.5 -induced heart acute injury is still unclear. In this study, the alterations of mitochondrial morphology and mitochondrial fission/fusion gene expression, oxidative stress, calcium homeostasis and inflammation in hearts of rats exposed to PM 2.5 with different dosages (0.375, 1.5, 6.0 and 24.0 mg/kg body weight) were investigated. The results indicated that the PM 2.5 exposure induced pathological changes and ultra-structural damage in hearts such as mitochondrial swell and cristae disorder. Furthermore, PM 2.5 exposure significantly increased specific mitochondrial fission/fusion gene (Fis1, Mfn1, Mfn2, Drp1 and OPA1) expression in rat hearts. These changes were accompanied by decreases of activities of superoxide dismutase (SOD), Na + K + -ATPase and Ca 2+ -ATPase and increases of levels of malondialdehyde (MDA), inducible nitric oxide synthase (iNOS) and nitric oxide (NO) as well as levels of pro-inflammatory mediators including TNF-α, IL-6 and IL-1β in rat hearts. The results implicate that mitochondrial damage, oxidative stress, cellular homeostasis imbalance and inflammation are potentially important mechanisms for the PM 2.5 -induced heart injury, and may have relations with cardiovascular disease

  5. The economic feasibility of producing hydrogen from sunlight and wind

    International Nuclear Information System (INIS)

    Mann, M. K.; Spath, P. L.; Watt, A. S.

    1999-01-01

    The feasibility of utilizing photoelectrochemical and electrolytical technologies to convert energy from the sun and wind into hydrogen was studied. In exploring opportunities to reduce the cost of hydrogen production through interaction with the electric utility grid, it was found that direct photoelectrochemical (PEC) conversion of sunlight has the economic potential to compete with direct photovoltaic/electrolysis, notwithstanding the significant stability and efficiency issues that are still awaiting solution. Interaction with the grid, while maximizing electrolizer use, makes a significant impact on the economics of producing hydrogen by photovoltaic/electrolysis, making wind-based systems also more economical. Electrolysis was found to be the optimal solution only with electricity from renewable sources or with less expensive non-peak electricity. On the other hand, the delivered cost of hydrogen was found to the lowest when electricity production was decoupled from the hydrogen production operation. Decoupled hydrogen production also has an additional benefit, i.e. it produces the hydrogen where it is needed, therefore it mitigates the need for various storage and distribution costs. 6 refs., 4 tabs., 2 figs

  6. Theory of direct sunlight transmission through orthogonal screen cells

    International Nuclear Information System (INIS)

    Aljofi, E.K.

    2006-01-01

    The Purpose of this paper is to investigate the feasibility of using the Rawshan screens to control high light intensity and to avoid excessive solar radiation penetrating inside the building interior. The exploration of the environmental characteristics of this device indicates an ideal solution to utilize available daylight in the arid atmosphere, reduces energy consumption due to the us of artificial light and ensures the continuity of the traditional architecture and the country heritage. A systematic analysis of direct sunlight transmission has been explored using a mathematical approach. The study intends to construct a predictive tool for the architects through which different specifications of the Rawshan screens were identified as far as direct beam of light concerned. The predictive tool was set-up to investigate various parameters of the screen such as the screen configurations, the aperture configurations, the change in orientation and the effect of the sky condition. The analysis of light transmission through the screen were set-up for orthogonal shapes

  7. Evaluation of the effects of repeated hand washing, sunlight, smoke and dirt on the persistence of deltamethrin on insecticide-treated nets.

    Science.gov (United States)

    Kayedi, M H; Lines, J D; Haghdoost, A A; Vatandoost, M H; Rassi, Y; Khamisabady, K

    2008-08-01

    Field studies were carried out in Iran to evaluate the effect of various factors (washing, sun, smoke, dust and dirt) on the residual insecticidal activity of PermaNet (a brand of long-lasting insecticidal net), and on nets conventionally treated with deltamethrin (K-O Tab), using bioassay tests. Thirty-two nets were washed five or 15 times, and eight nets were not washed at all. Nets were washed vigorously in cold tap water (17 degrees C, pH 8.9) with a detergent. Hand rubbing continued for 3min. After washing, some nets were exposed to dense smoke from a dung-hay fire for 3min and were also left exposed to the dusty wind between washes. One group of nets was exposed to the sunlight for the full 3-d interval between washes; another was exposed to sunlight for just 3h after each wash; two other groups were kept in the shade. There was a significantly greater loss of activity in nets exposed to the sun throughout the 3-d interval between washes: that is, for a total of 15 to 45 d. However, short sunlight exposure (maximum 3h between washes) during drying did not have any effect. We did not find any significant effect of exposure to dirt, dust and smoke after washing. It is concluded that the effect of sun is much smaller than that of washing, and that drying nets for a few hours in the sun is not harmful.

  8. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Marchini, T.; Magnani, N.D. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Paz, M.L. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Vanasco, V. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Tasat, D. [CESyMA, Facultad de Ciencia Tecnología, Universidad Nacional de General San Martín, Martín de Irigoyen 3100, 1650 San Martín, Buenos Aires (Argentina); González Maglio, D.H. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); and others

    2014-01-15

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

  10. Sunlight and Vitamin D: The Bone and Cancer Connections (invited paper)

    International Nuclear Information System (INIS)

    Holick, M.F.

    2000-01-01

    Vitamin D plays an essential role for calcium metabolism and bone health. It has been estimated that 90 to 95% of our vitamin D requirement comes from casual exposure to sunlight. There is a wide variety of factors that strongly influence the cutaneous production of vitamin D. These include melanin pigmentation, latitude, time of day, sunscreen use, and aging. There is an association with increased risk and mortality to breast, colon, and prostrate cancer. There is evidence that 25-hydroxyvitamin D, the major circulating form of vitamin D, is directly metabolised in prostate, breast, colon, and skin cells to its active form 1,25-dihydroxyvitamin D. 1,25-Dihydroxyvitamin D 3 has the capacity to regulate cell proliferation and differentiation. Therefore, it may be that an increase in the cutaneous synthesis of vitamin D results in the increase in the production of 1,25(OH) 2 D in tissues not related to calcium metabolism that results in a decrease in malignancy. (author)

  11. Photo-induced toxicity in early life stage fiddler crab (Uca longisignalis) following exposure to Deepwater Horizon oil.

    Science.gov (United States)

    Damare, Leigh M; Bridges, Kristin N; Alloy, Matthew M; Curran, Thomas E; Soulen, Brianne K; Forth, Heather P; Lay, Claire R; Morris, Jeffrey M; Stoeckel, James A; Roberts, Aaron P

    2018-05-01

    The 2010 explosion of the Deepwater Horizon (DWH) oil rig led to the release of millions of barrels of oil in the Gulf of Mexico. Oil in aquatic ecosystems exerts toxicity through multiple mechanisms, including photo-induced toxicity following co-exposure with UV radiation. The timing and location of the spill coincided with both fiddler crab reproduction and peak yearly UV intensities, putting early life stage fiddler crabs at risk of injury due to photo-induced toxicity. The present study assessed sensitivity of fiddler crab larvae to photo-induced toxicity during co-exposure to a range of environmentally relevant dilutions of high-energy water accommodated fractions of DWH oil, and either dark recovery period (duration: 17-h) in between. Survival was significantly decreased in treatments the presence of >10% UV and relatively low concentrations of oil. Results of the present study indicate fiddler crab larvae are sensitive to photo-induced toxicity in the presence of DWH oil. These results are of concern, as fiddler crabs play an important role as ecosystem engineers, modulating sediment biogeochemical processes via burrowing action. Furthermore, they occupy an important place in the food web in the Gulf of Mexico.

  12. Early-life viral infection and allergen exposure interact to induce an asthmatic phenotype in mice

    Directory of Open Access Journals (Sweden)

    Asquith Kelly L

    2010-02-01

    Full Text Available Abstract Background Early-life respiratory viral infections, notably with respiratory syncytial virus (RSV, increase the risk of subsequent development of childhood asthma. The purpose of this study was to assess whether early-life infection with a species-specific model of RSV and subsequent allergen exposure predisposed to the development of features of asthma. Methods We employed a unique combination of animal models in which BALB/c mice were neonatally infected with pneumonia virus of mice (PVM, which replicates severe RSV disease in human infants and following recovery, were intranasally sensitised with ovalbumin. Animals received low-level challenge with aerosolised antigen for 4 weeks to elicit changes of chronic asthma, followed by a single moderate-level challenge to induce an exacerbation of inflammation. We then assessed airway inflammation, epithelial changes characteristic of remodelling, airway hyperresponsiveness (AHR and host immunological responses. Results Allergic airway inflammation, including recruitment of eosinophils, was prominent only in animals that had recovered from neonatal infection with PVM and then been sensitised and chronically challenged with antigen. Furthermore, only these mice exhibited an augmented Th2-biased immune response, including elevated serum levels of anti-ovalbumin IgE and IgG1 as well as increased relative expression of Th2-associated cytokines IL-4, IL-5 and IL-13. By comparison, development of AHR and mucous cell change were associated with recovery from PVM infection, regardless of subsequent allergen challenge. Increased expression of IL-25, which could contribute to induction of a Th2 response, was demonstrable in the lung following PVM infection. Signalling via the IL-4 receptor α chain was crucial to the development of allergic inflammation, mucous cell change and AHR, because all of these were absent in receptor-deficient mice. In contrast, changes of remodelling were evident in mice

  13. Preventive effect of curcumin and its highly bioavailable preparation on hearing loss induced by single or repeated exposure to noise: A comparative and mechanistic study

    Directory of Open Access Journals (Sweden)

    Taro Yamaguchi

    2017-08-01

    Full Text Available We sought to determine the preventive effects of curcumin and its highly bioavailable preparation on noise-induced hearing loss in a novel murine model of permanent hearing loss developed by repeated exposure to noise. Upon exposure to noise (8-kHz octave band noise, 90 dB sound pressure level, 1 h, hearing ability was impaired in a temporary and reversible manner. During repeated noise exposure (1-h exposure per day, 5 days, there was a progressive increase in the auditory threshold shift at 12 and 20 kHz. The threshold shift persisted for at least 6 days after noise exposure. Oral administration of curcumin for 3 days before and each day during noise exposure significantly alleviated the hearing loss induced by repeated noise exposure. Curcumin abolished intranuclear translocation of nuclear factor-κB-p65 and generation of 4-hydroxynonenal-adducted proteins found in the cochlea after noise exposure. Theracurmin®, a highly absorbable and bioavailable preparation of curcumin, had strong preventive effects on hearing loss induced by repeated noise exposure. Together, these data suggest that curcumin exerts a preventive effect on noise-induced hearing loss and is therefore a good therapeutic candidate for preventing sensorineural hearing loss.

  14. Preventive effect of curcumin and its highly bioavailable preparation on hearing loss induced by single or repeated exposure to noise: A comparative and mechanistic study.

    Science.gov (United States)

    Yamaguchi, Taro; Yoneyama, Masanori; Onaka, Yusuke; Imaizumi, Atsushi; Ogita, Kiyokazu

    2017-08-01

    We sought to determine the preventive effects of curcumin and its highly bioavailable preparation on noise-induced hearing loss in a novel murine model of permanent hearing loss developed by repeated exposure to noise. Upon exposure to noise (8-kHz octave band noise, 90 dB sound pressure level, 1 h), hearing ability was impaired in a temporary and reversible manner. During repeated noise exposure (1-h exposure per day, 5 days), there was a progressive increase in the auditory threshold shift at 12 and 20 kHz. The threshold shift persisted for at least 6 days after noise exposure. Oral administration of curcumin for 3 days before and each day during noise exposure significantly alleviated the hearing loss induced by repeated noise exposure. Curcumin abolished intranuclear translocation of nuclear factor-κB-p65 and generation of 4-hydroxynonenal-adducted proteins found in the cochlea after noise exposure. Theracurmin ® , a highly absorbable and bioavailable preparation of curcumin, had strong preventive effects on hearing loss induced by repeated noise exposure. Together, these data suggest that curcumin exerts a preventive effect on noise-induced hearing loss and is therefore a good therapeutic candidate for preventing sensorineural hearing loss. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  15. Exposure to titanium dioxide and other metallic oxide nanoparticles induces cytotoxicity on human neural cells and fibroblasts

    Directory of Open Access Journals (Sweden)

    James C K Lai

    2008-12-01

    Full Text Available James C K Lai1, Maria B Lai1, Sirisha Jandhyam1, Vikas V Dukhande1, Alok Bhushan1, Christopher K Daniels1, Solomon W Leung21Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, and Biomedical Research Institute; 2Department of Civil and Environmental Engineering, College of Engineering and Biomedical Research Institute, Idaho State University, Pocatello, ID, USAAbstract: The use of titanium dioxide (TiO2 in various industrial applications (eg, production of paper, plastics, cosmetics, and paints has been expanding thereby increasing the occupational and other environmental exposure of these nanoparticles to humans and other species. However, the health effects of exposure to TiO2 nanoparticles have not been systematically assessed even though recent studies suggest that such exposure induces inflammatory responses in lung tissue and cells. Because the effects of such nanoparticles on human neural cells are unknown, we have determined the putative cytotoxic effects of these nanoparticles on human astrocytes-like astrocytoma U87 cells and compared their effects on normal human fibroblasts. We found that TiO2 micro- and nanoparticles induced cell death on both human cell types in a concentration-related manner. We further noted that zinc oxide (ZnO nanoparticles were the most effective, TiO2 nanoparticles the second most effective, and magnesium oxide (MgO nanoparticles the least effective in inducing cell death in U87 cells. The cell death mechanisms underlying the effects of TiO2 micro- and nanoparticles on U87 cells include apoptosis, necrosis, and possibly apoptosis-like and necrosis-like cell death types. Thus, our findings may have toxicological and other pathophysiological implications on exposure of humans and other mammalian species to metallic oxide nanoparticles.Keywords: cytotoxicity of titanium dioxide micro- and nanoparticles, cytotoxicity of zinc oxide and magnesium oxide nanoparticles, human neural cells

  16. Protective effect of curcumin on pulmonary and cardiovascular effects induced by repeated exposure to diesel exhaust particles in mice.

    Directory of Open Access Journals (Sweden)

    Abderrahim Nemmar

    Full Text Available Particulate air pollution has been associated with increased risk of cardiopulmonary diseases. However, the underlying mechanisms are not fully understood. We have previously demonstrated that single dose exposure to diesel exhaust particle (DEP causes lung inflammation and peripheral thrombotic events. Here, we exposed mice with repeated doses of DEP (15 µg/animal every 2(nd day for 6 days (a total of 4 exposures, and measured several cardiopulmonary endpoints 48 h after the end of the treatments. Moreover, the potential protective effect of curcumin (the yellow pigment isolated from turmeric on DEP-induced cardiopulmonary toxicity was assessed. DEP exposure increased macrophage and neutrophil numbers, tumor necrosis factor α (TNF α in the bronchoalveolar lavage (BAL fluid, and enhanced airway resistance to methacoline measured invasively using Flexivent. DEP also significantly increased plasma C-reactive protein (CRP and TNF α concentrations, systolic blood pressure (SBP as well as the pial arteriolar thrombosis. It also significantly enhanced the plasma D-dimer and plasminogen activator inhibitor-1 (PAI-1. Pretreatment with curcumin by oral gavage (45 mg/kg 1 h before exposure to DEP significantly prevented the influx of inflammatory cells and the increase of TNF α in BAL, and the increased airway resistance caused by DEP. Likewise, curcumin prevented the increase of SBP, CRP, TNF α, D-dimer and PAI-1. The thrombosis was partially but significantly mitigated. In conclusion, repeated exposure to DEP induced lung and systemic inflammation characterized by TNFα release, increased SBP, and accelerated coagulation. Our findings indicate that curcumin is a potent anti-inflammatory agent that prevents the release of TNFα and protects against the pulmonary and cardiovascular effects of DEP.

  17. Cold Exposure Induces Proliferation of Mature Brown Adipocyte in a ß3-Adrenergic Receptor-Mediated Pathway.

    Science.gov (United States)

    Fukano, Keigo; Okamatsu-Ogura, Yuko; Tsubota, Ayumi; Nio-Kobayashi, Junko; Kimura, Kazuhiro

    2016-01-01

    Hyperplasia of brown adipose tissue (BAT) is a fundamental mechanism for adaptation to survive in the cold environment in rodents. To determine which cell types comprising BAT contribute to tissue hyperplasia, immunohistochemical analysis using a proliferative marker Ki67 was performed on the BAT from 6-week-old C57BL/6J mice housed at 23°C (control) or 10°C (cold) for 5 days. Interestingly, in the control group, the cell proliferative marker Ki67 was detected in the nuclei of uncoupling protein 1-positive mature brown adipocytes (7.2% ± 0.4% of brown adipocyte), as well as in the non-adipocyte stromal-vascular (SV) cells (19.6% ± 2.3% of SV cells), which include preadiopocytes. The percentage of Ki67-positive brown adipocytes increased to 25.6% ± 1.8% at Day 1 after cold exposure and was significantly higher than the non-cold acclimated control until Day 5 (21.8% ± 1.7%). On the other hand, the percentage of Ki67-positive SV cells gradually increased by a cold exposure and peaked to 42.1% ± 8.3% at Day 5. Injection of a ß3-adrenergic receptor (ß3-AR) agonist for continuous 5 days increased the number of Ki67-positive brown adipocytes even at Day 1 but not that of SV cells. In addition, the ß3-AR antagonist, but not ß1-AR antagonist, attenuated the cold exposure-induced increase in the number of Ki67-positive brown adipocytes. These results suggest that mature brown adipocytes proliferate immediately after cold exposure in a ß3-AR-mediated pathway. Thus, proliferation of mature brown adipocytes as well as preadipocytes in SV cells may contribute to cold exposure-induced BAT hyperplasia.

  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. Prenatal air pollution exposure induces sexually dimorphic fetal programming of metabolic and neuroinflammatory outcomes in adult offspring.

    Science.gov (United States)

    Bolton, Jessica L; Auten, Richard L; Bilbo, Staci D

    2014-03-01

    Environmental chemical exposures during critical windows of development may contribute to the escalating prevalence of obesity. We tested the hypothesis that prenatal exposure to diesel exhaust particles (DEP), a primary component of air pollution, would prime microglia long-term, resulting in exacerbated metabolic and affective outcomes following exposure to a high-fat diet in adulthood. Time-mated mouse dams were intermittently exposed to respiratory instillations of either vehicle (VEH) or DEP throughout gestation. Adult male and female offspring were then fed either a low-fat diet (LFD) or high-fat diet (HFD) for 9 weeks. The male offspring of DEP-exposed dams exhibited exaggerated weight gain, insulin resistance, and anxiety-like behavior on HFD compared to the male offspring of VEH-exposed dams, whereas female offspring did not differ according to prenatal treatment. Furthermore, HFD induced evidence of macrophage infiltration of both adipose tissue and the brain in both sexes, but these cells were more activated specifically in DEP/HFD males. DEP/HFD males also expressed markedly higher levels of microglial/macrophage, but not astrocyte, activation markers in the hippocampus, whereas females exhibited only a suppression of astrocyte activation markers due to HFD. In a second experiment, DEP male offspring mounted an exaggerated peripheral IL-1β response to an LPS challenge at postnatal day (P)30, whereas their central IL-1β response did not differ from VEH male offspring, which is suggestive of macrophage priming due to prenatal DEP exposure. In sum, prenatal air pollution exposure "programs" offspring for increased susceptibility to diet-induced metabolic, behavioral, and neuroinflammatory changes in adulthood in a sexually dimorphic manner. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Sunlight-exposed biofilm microbial communities are naturally resistant to chernobyl ionizing-radiation levels.

    Directory of Open Access Journals (Sweden)

    Marie Ragon

    Full Text Available BACKGROUND: The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta and ascomycete fungi (Ascomycota dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. CONCLUSIONS/SIGNIFICANCE: Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in

  1. Sunlight-Exposed Biofilm Microbial Communities Are Naturally Resistant to Chernobyl Ionizing-Radiation Levels

    Science.gov (United States)

    Ragon, Marie; Restoux, Gwendal; Moreira, David; Møller, Anders Pape; López-García, Purificación

    2011-01-01

    Background The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. Methodology/Principal Findings To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. Conclusions/Significance Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general

  2. Paraquat and maneb co-exposure induces noradrenergic locus coeruleus neurodegeneration through NADPH oxidase-mediated microglial activation

    International Nuclear Information System (INIS)

    Hou, Liyan; Zhang, Cong; Wang, Ke; Liu, Xiaofang; Wang, Hongwei; Che, Yuning; Sun, Fuqiang; Zhou, Xueying; Zhao, Xiulan; Wang, Qingshan

    2017-01-01

    Highlights: • Microglial activation induced by paraquat and maneb precedes noradrenergic neurodegeneration in locus coeruleus. • NADPH oxidase activation contributes to microglia-mediated neuroinflammation and related noradrenergic neurodegeneration. • Inhibition of NADPH oxidase by apocynin protects noradrenergic neurons against paraquat and maneb-induced toxicity. - Abstract: Co-exposure to paraquat (PQ) and maneb (Mb) has been shown to increase the risk of Parkinson’s disease (PD) and dopaminergic (DA) neurodegeneration in the substantia nigra pars compacta (SNpc) is observed in PQ and Mb-treated experimental animals. The loss of noradrenergic locus coeruleus (LC/NE) neurons in brainstem is a common feature shared by multiple neurodegenerative diseases, including PD. However, whether PQ and Mb is able to damage LC/NE neurons remains undefined. In this study, mice treated with combined PQ and Mb displayed progressive LC/NE neurodegeneration. Time course studies revealed that the activation of microglia preceded LC/NE neurodegeneration. Mechanistically, the activation of NADPH oxidase contributed to microglial activation and subsequent LC/NE neurodegeneration. We found that PQ and Mb co-exposure induced activation of NADPH oxidase as shown by increased superoxide production and membrane translocation of p47 phox , a cytosolic subunit of NADPH oxidase. Inhibition of NADPH oxidase by apocynin, a widely used NADPH oxidase inhibitor, suppressed microglial activation and gene expressions of proinflammatory factors. Furthermore, reduced activation of nuclear factor-κB (NF-κB) pathway was observed in apocynin-treated mice. More importantly, inhibition of NADPH oxidase by apocynin afforded LC/NE neuroprotection against PQ and Mb-induced neurotoxicity. Thus, our findings revealed the critical role NADPH oxidase-mediated microglial activation in driving LC/NE neurodegeneration induced by PQ and Mb, providing new insights into the pathogenesis of environmental

  3. Motor activity changes induced by sub-encephalopathic lead exposure during different developmental phases in rats

    International Nuclear Information System (INIS)

    Van Rooyen, J.M.; Offermeier, J.; Brand, L.; Botha, F.; Rossouw, J.; Lategan, A.J.; Botes, M.S.

    1988-01-01

    Two groups of rats were exposed to lead (0,2% lead acetate in drinking water) for periods of 21 days during different developmental phases. Lead exposure was initiated on day 1 and day 22 after birth, for rats in groups 1 and 2, respectively. Measurements of locomotor activity (LA) and [ 3 H]spiperone binding assays were performed on day 50 after birth. Lead exposure resulted in the potentiation of the LA effects of 5 mg/kg apomorphine without altering the LA effects of 50 mg/kg piribedil in group 1. Lead exposure resulted in an attenuation of the LA effects of apomorphine and piribedil in group 2. Lead exposure did not alter the K D and B max values of [ 3 H]spiperone in membranes prepared from the rat striatum or nucleus accumbens

  4. Motor activity changes induced by sub-encephalopathic lead exposure during different developmental phases in rats

    Energy Technology Data Exchange (ETDEWEB)

    Van Rooyen, J M; Offermeier, J; Brand, L; Botha, F; Rossouw, J; Lategan, A J; Botes, M S

    1988-05-01

    Two groups of rats were exposed to lead (0,2% lead acetate in drinking water) for periods of 21 days during different developmental phases. Lead exposure was initiated on day 1 and day 22 after birth, for rats in groups 1 and 2, respectively. Measurements of locomotor activity (LA) and (/sup 3/H)spiperone binding assays were performed on day 50 after birth. Lead exposure resulted in the potentiation of the LA effects of 5 mg/kg apomorphine without altering the LA effects of 50 mg/kg piribedil in group 1. Lead exposure resulted in an attenuation of the LA effects of apomorphine and piribedil in group 2. Lead exposure did not alter the K/sub D/ and B/sub max/ values of (/sup 3/H)spiperone in membranes prepared from the rat striatum or nucleus accumbens.

  5. Prenatal ethanol exposure-induced adrenal developmental abnormality of male offspring rats and its possible intrauterine programming mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hegui; He, Zheng; Zhu, Chunyan; Liu, Lian; Kou, Hao; Shen, Lang [Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan 430071 (China); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan 430071 (China); Hubei Provincial Key Laboratory of Developmentally Originated Disorder, Wuhan 430071 (China)

    2015-10-01

    Fetal adrenal developmental status is the major determinant of fetal tissue maturation and offspring growth. We have previously proposed that prenatal ethanol exposure (PEE) suppresses fetal adrenal corticosterone (CORT) synthesis. Here, we focused on PEE-induced adrenal developmental abnormalities of male offspring rats before and after birth, and aimed to explore its intrauterine programming mechanisms. A rat model of intrauterine growth retardation (IUGR) was established by PEE (4 g/kg·d). In PEE fetus, increased serum CORT concentration and decreased insulin-like growth factor 1 (IGF1) concentration, with lower bodyweight and structural abnormalities as well as a decreased Ki67 expression (proliferative marker), were observed in the male fetal adrenal cortex. Adrenal glucocorticoid (GC)-metabolic activation system was enhanced while gene expression of IGF1 signaling pathway with steroidogenic acute regulatory protein (StAR), 3β-hydroxysteroid dehydrogenase (3β-HSD) was decreased. Furthermore, in the male adult offspring of PEE, serum CORT level was decreased but IGF1 was increased with partial catch-up growth, and Ki67 expression demonstrated no obvious change. Adrenal GC-metabolic activation system was inhibited, while IGF1 signaling pathway and 3β-HSD was enhanced with the steroidogenic factor 1 (SF1), and StAR was down-regulated in the adult adrenal. Based on these findings, we propose a “two-programming” mechanism for PEE-induced adrenal developmental toxicity: “the first programming” is a lower functional programming of adrenal steroidogenesis, and “the second programming” is GC-metabolic activation system-related GC-IGF1 axis programming. - Highlights: • Prenatal ethanol exposure induces adrenal developmental abnormality in offspring rats. • Prenatal ethanol exposure induces intrauterine programming of adrenal steroidogenesis. • Intrauterine GC-IGF1 axis programming might mediate adrenal developmental abnormality.

  6. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Directory of Open Access Journals (Sweden)

    A. Zago

    2012-01-01

    Full Text Available Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although cross-sensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P 28-37 and adult (P60-67 rats received nicotine (0.4 mg/kg, sc or saline (0.9% NaCl, sc and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  7. Alantolactone Improves Prolonged Exposure of Interleukin-6-Induced Skeletal Muscle Inflammation Associated Glucose Intolerance and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Minjee Kim

    2017-06-01

    Full Text Available The pro-inflammatory cytokine, Interleukin-6 (IL-6, has been proposed to be one of the mediators that link chronic inflammation to glucose intolerance and insulin resistance. Many studies have demonstrated the effects of IL-6 on insulin action in the skeletal muscle. However, few studies have investigated the effect of long-term treatment of IL-6, leading to glucose intolerance and insulin resistance. In the present study, we observed protective effects of alantolactone, a sesquiterpene lactone isolated from Inula helenium against glucose intolerance and insulin resistance induced by prolonged exposure of IL-6. Alantolactone has been reported to have anti-inflammatory and anti-cancer effects through IL-6-induced signal transducer and activator of transcription 3 (STAT3 signaling pathway. The relationship between IL-6 exposure and expression of toll-like receptor 4 (TLR4, involved in inflammation in the skeletal muscle, and the underlying mechanisms were investigated. We observed maximum dysregulation of glucose uptake after 40 ng/ml IL-6 induction for 24 h in L6 myotubes. Prolonged IL-6 exposure suppressed glucose uptake regulating alpha serine/threonine-protein kinase (AKT phosphorylation; however, pretreatment with alantolactone activated AKT phosphorylation and improved glucose uptake. Alantolactone also attenuated IL-6-stimulated STAT3 phosphorylation, followed by an increase in expression of negative regulator suppressor of cytokine signaling 3 (SOCS3. Furthermore, IL-6-induced expression of pathogen recognition receptor, TLR4, was also suppressed by alantolactone pretreatment. Post-silencing of STAT3 using siRNA approach, IL-6-stimulated siRNA-STAT3 improved glucose uptake and suppressed TLR4 gene expression. Taken together, we propose that, as a STAT3 inhibitor, alantolactone, improves glucose regulation in the skeletal muscle by inhibiting IL-6-induced STAT3-SOCS3 signaling followed by inhibition of the TLR4 gene expression. Therefore

  8. Severe, multimodal stress exposure induces PTSD-like characteristics in a mouse model of single prolonged stress.

    Science.gov (United States)

    Perrine, Shane A; Eagle, Andrew L; George, Sophie A; Mulo, Kostika; Kohler, Robert J; Gerard, Justin; Harutyunyan, Arman; Hool, Steven M; Susick, Laura L; Schneider, Brandy L; Ghoddoussi, Farhad; Galloway, Matthew P; Liberzon, Israel; Conti, Alana C

    2016-04-15

    Appropriate animal models of posttraumatic stress disorder (PTSD) are needed because human studies remain limited in their ability to probe the underlying neurobiology of PTSD. Although the single prolonged stress (SPS) model is an established rat model of PTSD, the development of a similarly-validated mouse model emphasizes the benefits and cross-species utility of rodent PTSD models and offers unique methodological advantages to that of the rat. Therefore, the aims of this study were to develop and describe a SPS model for mice and to provide data that support current mechanisms relevant to PTSD. The mouse single prolonged stress (mSPS) paradigm, involves exposing C57Bl/6 mice to a series of severe, multimodal stressors, including 2h restraint, 10 min group forced swim, exposure to soiled rat bedding scent, and exposure to ether until unconsciousness. Following a 7-day undisturbed period, mice were tested for cue-induced fear behavior, effects of paroxetine on cue-induced fear behavior, extinction retention of a previously extinguished fear memory, dexamethasone suppression of corticosterone (CORT) response, dorsal hippocampal glucocorticoid receptor protein and mRNA expression, and prefrontal cortex glutamate levels. Exposure to mSPS enhanced cue-induced fear, which was attenuated by oral paroxetine treatment. mSPS also disrupted extinction retention, enhanced suppression of stress-induced CORT response, increased mRNA expression of dorsal hippocampal glucocorticoid receptors and decreased prefrontal cortex glutamate levels. These data suggest that the mSPS model is a translationally-relevant model for future PTSD research with strong face, construct, and predictive validity. In summary, mSPS models characteristics relevant to PTSD and this severe, multimodal stress modifies fear learning in mice that coincides with changes in the hypothalamo-pituitary-adrenal (HPA) axis, brain glucocorticoid systems, and glutamatergic signaling in the prefrontal cortex

  9. Prenatal ethanol exposure-induced adrenal developmental abnormality of male offspring rats and its possible intrauterine programming mechanisms

    International Nuclear Information System (INIS)

    Huang, Hegui; He, Zheng; Zhu, Chunyan; Liu, Lian; Kou, Hao; Shen, Lang; Wang, Hui

    2015-01-01

    Fetal adrenal developmental status is the major determinant of fetal tissue maturation and offspring growth. We have previously proposed that prenatal ethanol exposure (PEE) suppresses fetal adrenal corticosterone (CORT) synthesis. Here, we focused on PEE-induced adrenal developmental abnormalities of male offspring rats before and after birth, and aimed to explore its intrauterine programming mechanisms. A rat model of intrauterine growth retardation (IUGR) was established by PEE (4 g/kg·d). In PEE fetus, increased serum CORT concentration and decreased insulin-like growth factor 1 (IGF1) concentration, with lower bodyweight and structural abnormalities as well as a decreased Ki67 expression (proliferative marker), were observed in the male fetal adrenal cortex. Adrenal glucocorticoid (GC)-metabolic activation system was enhanced while gene expression of IGF1 signaling pathway with steroidogenic acute regulatory protein (StAR), 3β-hydroxysteroid dehydrogenase (3β-HSD) was decreased. Furthermore, in the male adult offspring of PEE, serum CORT level was decreased but IGF1 was increased with partial catch-up growth, and Ki67 expression demonstrated no obvious change. Adrenal GC-metabolic activation system was inhibited, while IGF1 signaling pathway and 3β-HSD was enhanced with the steroidogenic factor 1 (SF1), and StAR was down-regulated in the adult adrenal. Based on these findings, we propose a “two-programming” mechanism for PEE-induced adrenal developmental toxicity: “the first programming” is a lower functional programming of adrenal steroidogenesis, and “the second programming” is GC-metabolic activation system-related GC-IGF1 axis programming. - Highlights: • Prenatal ethanol exposure induces adrenal developmental abnormality in offspring rats. • Prenatal ethanol exposure induces intrauterine programming of adrenal steroidogenesis. • Intrauterine GC-IGF1 axis programming might mediate adrenal developmental abnormality.

  10. Exposure to coplanar PCBs induces endothelial cell inflammation through epigenetic regulation of NF-κB subunit p65

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dandan; Perkins, Jordan T. [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40536 (United States); Petriello, Michael C. [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Graduate Center for Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Hennig, Bernhard, E-mail: bhennig@uky.edu [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40536 (United States)

    2015-12-15

    Epigenetic modifications of DNA and histones alter cellular phenotypes without changing genetic codes. Alterations of epigenetic marks can be induced by exposure to environmental pollutants and may contribute to associated disease risks. Here we test the hypothesis that endothelial cell dysfunction induced by exposure to polychlorinated biphenyls (PCBs) is mediated in part though histone modifications. In this study, human vascular endothelial cells were exposed to physiologically relevant concentrations of several PCBs congeners (e.g., PCBs 77, 118, 126 and 153) followed by quantification of inflammatory gene expression and changes of histone methylation. Only exposure to coplanar PCBs 77 and 126 induced the expression of histone H3K9 trimethyl demethylase jumonji domain-containing protein 2B (JMJD2B) and nuclear factor-kappa B (NF-κB) subunit p65, activated NF-κB signaling as evidenced by nuclear translocation of p65, and up-regulated p65 target inflammatory genes, such as interleukin (IL)-6, C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and IL-1α/β. The increased accumulation of JMJD2B in the p65 promoter led to a depletion of H3K9me3 repression mark, which accounts for the observed up-regulation of p65 and associated inflammatory genes. JMJD2B gene knockdown confirmed a critical role for this histone demethylase in mediating PCB-induced inflammation of the vascular endothelium. Finally, it was determined, via chemical inhibition, that PCB-induced up-regulation of JMJD2B was estrogen receptor-alpha (ER-α) dependent. These data suggest that coplanar PCBs may exert endothelial cell toxicity through changes in histone modifications. - Highlights: • Coplanar PCBs significantly induced histone demethylase JMJD2B expression. • Coplanar PCBs activated NF-κB through p65 up-regulation and nuclear translocation. • Histone H3K4 and K9 modifications were mediated by ER-α/JMJD2B/MLL2 complex.

  11. Daytime Cognitive Performance in Response to Sunlight or Fluorescent Light Controlling for Sleep Duration

    Science.gov (United States)

    Ramos, Jhanic; Zamos, Adela; Rao, Rohit; Flynn-Evans, Erin

    2015-01-01

    Light is the primary synchronizer of the human circadian rhythm and also has acute alerting effects. Our study involves and comparing the alertness, performance and sleep of participants in the NASA Ames Sustainability Base, which uses sunlight as its primary light source, to in a traditional office building which uses overhead florescent lighting and varying exposure to natural light. The purpose of this study is to determine whether the use of natural lighting as a primary light source improves daytime cognitive function and promotes nighttime sleep. Participants from the Sustainability Base will be matched by gender and age to individuals working in other NASA buildings. In a prior study we found no differences in performance between those working in the Sustainability Base and those working in other buildings. Unexpectedly, we found that the average sleep duration among participants in both buildings was short, which likely obscured our ability to detect a difference the effect of light exposure on alertness. Given that such sleep deprivation has negative effects on cognitive performance, in this iteration of the study we are asking the participants to maintain a regular schedule with eight hours in bed each night in order to control for the effect of self-selected sleep restriction. Over the course of one week, we will ask the participants to wear actiwatches continuously, complete a psychomotor vigilance task (PVT) and digit symbol substitution task (DSST) three times per day, and keep daily sleepwork diaries. We hope that this study will provide data to support the idea that natural lighting and green architectural design are optimal to enhance healthy nighttime sleep patterns and daytime cognitive performance.

  12. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

    International Nuclear Information System (INIS)

    Silva, Danielle Cristina Tomaz da; Lima-Leopoldo, Ana Paula; Leopoldo, André Soares; Campos, Dijon Henrique Salomé de; Nascimento, André Ferreira do; Oliveira, Sílvio Assis Junior de; Padovani, Carlos Roberto; Cicogna, Antonio Carlos

    2014-01-01

    Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C 15 and Ob 15 ) and 30 (C 30 and Ob 30 ) consecutive weeks. Obesity was determined by adiposity index. The Ob 15 group was similar to the C 15 group regarding the expression of myocardial collagen type I; however, expression in the Ob 30 group was less than C 30 group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob 30 when compared with Ob 15 . Obesity did not affect collagen type III expression. This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression

  13. Short-term exposure to enriched environment rescues chronic stress-induced impaired hippocampal synaptic plasticity, anxiety, and memory deficits.

    Science.gov (United States)

    Bhagya, Venkanna Rao; Srikumar, Bettadapura N; Veena, Jayagopalan; Shankaranarayana Rao, Byrathnahalli S

    2017-08-01

    Exposure to prolonged stress results in structural and functional alterations in the hippocampus including reduced long-term potentiation (LTP), neurogenesis, spatial learning and working memory impairments, and enhanced anxiety-like behavior. On the other hand, enriched environment (EE) has beneficial effects on hippocampal structure and function, such as improved memory, increased hippocampal neurogenesis, and progressive synaptic plasticity. It is unclear whether exposure to short-term EE for 10 days can overcome restraint stress-induced cognitive deficits and impaired hippocampal plasticity. Consequently, the present study explored the beneficial effects of short-term EE on chronic stress-induced impaired LTP, working memory, and anxiety-like behavior. Male Wistar rats were subjected to chronic restraint stress (6 hr/day) over a period of 21 days, and then they were exposed to EE (6 hr/day) for 10 days. Restraint stress reduced hippocampal CA1-LTP, increased anxiety-like symptoms in elevated plus maze, and impaired working memory in T-maze task. Remarkably, EE facilitated hippocampal LTP, improved working memory performance, and completely overcame the effect of chronic stress on anxiety behavior. In conclusion, exposure to EE can bring out positive effects on synaptic plasticity in the hippocampus and thereby elicit its beneficial effects on cognitive functions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Influence of Term of Exposure to High-Fat Diet-Induced Obesity on Myocardial Collagen Type I and III

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Danielle Cristina Tomaz da [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Lima-Leopoldo, Ana Paula; Leopoldo, André Soares [Departamento de Esportes, Centro de Educação Física e Desportos da Universidade Federal do Espírito Santo (UFES), Vitória, ES (Brazil); Campos, Dijon Henrique Salomé de; Nascimento, André Ferreira do [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Oliveira, Sílvio Assis Junior de [Escola de Fisioterapia da Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil); Padovani, Carlos Roberto [Departamento de Bioestatística do Instituto de Ciências Biológicas da Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Cicogna, Antonio Carlos, E-mail: dany.tomaz@gmail.com [Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil)

    2014-02-15

    Obesity is a risk factor for many medical complications; medical research has shown that hemodynamic, morphological and functional abnormalities are correlated with the duration and severity of obesity. Present study determined the influence of term of exposure to high-fat diet-induced obesity on myocardial collagen type I and III. Thirty-day-old male Wistar rats were randomly distributed into two groups: a control (C) group fed a standard rat chow and an obese (Ob) group alternately fed one of four palatable high-fat diets. Each diet was changed daily, and the rats were maintained on their respective diets for 15 (C{sub 15} and Ob{sub 15}) and 30 (C{sub 30} and Ob{sub 30}) consecutive weeks. Obesity was determined by adiposity index. The Ob{sub 15} group was similar to the C{sub 15} group regarding the expression of myocardial collagen type I; however, expression in the Ob{sub 30} group was less than C{sub 30} group. The time of exposure to obesity was associated with a reduction in collagen type I in Ob{sub 30} when compared with Ob{sub 15}. Obesity did not affect collagen type III expression. This study showed that the time of exposure to obesity for 30 weeks induced by unsaturated high-fat diet caused a reduction in myocardial collagen type I expression in the obese rats. However, no effect was seen on myocardial collagen type III expression.

  15. Maternal L-glutamine supplementation prevents prenatal alcohol exposure-induced fetal growth restriction in an ovine model.

    Science.gov (United States)

    Sawant, Onkar B; Wu, Guoyao; Washburn, Shannon E

    2015-06-01

    Prenatal alcohol exposure is known to cause fetal growth restriction and disturbances in amino acid bioavailability. Alterations in these parameters can persist into adulthood and low birth weight can lead to altered fetal programming. Glutamine has been associated with the synthesis of other amino acids, an increase in protein synthesis and it is used clinically as a nutrient supplement for low birth weight infants. The aim of this study was to explore the effect of repeated maternal alcohol exposure and L-glutamine supplementation on fetal growth and amino acid bioavailability during the third trimester-equivalent period in an ovine model. Pregnant sheep were randomly assigned to four groups, saline control, alcohol (1.75-2.5 g/kg), glutamine (100 mg/kg, three times daily) or alcohol + glutamine. In this study, a weekend binge drinking model was followed where treatment was done 3 days per week in succession from gestational day (GD) 109-132 (normal term ~147). Maternal alcohol exposure significantly reduced fetal body weight, height, length, thoracic girth and brain weight, and resulted in decreased amino acid bioavailability in fetal plasma and placental fluids. Maternal glutamine supplementation successfully mitigated alcohol-induced fetal growth restriction and improved the bioavailability of glutamine and glutamine-related amino acids such as glycine, arginine, and asparagine in the fetal compartment. All together, these findings show that L-glutamine supplementation enhances amino acid availability in the fetus and prevents alcohol-induced fetal growth restriction.

  16. Radiation-induced emesis in cats prevented by 24-hour prior exposure but not by ablation of the area postrema

    International Nuclear Information System (INIS)

    McCarthy, L.E.; Borison, H.L.; Douple, E.B.

    1985-01-01

    The acute emetic response induced by whole body exposure to cobalt radiation was quantified in cats at doses ranging from 1500 to 9000 rad (100 rad/min). Emesis occurred in a dose-related manner with a maximum incidence of 94% at 4500 rad (11 of 12 cats, mean latency of 98 min). At 6000 rad emesis occurred in 7 of 10 cats (mean latency of 69 min); however, a second exposure to this dose on the following day failed to induce vomiting in all of 5 cats (difference between groups significant at p = .01). After chronic ablation of the area postrema (chemoreceptor trigger zone for vomiting), 4 of 5 cats vomited in response to 4500 rad with a mean latency of 48 min. As was the case with the normal cats, all the postrema-ablated animals failed to vomit in response to a repeated dose of radiation delivered on the next day. The suppression of emesis observed on the second exposure was radiation-specific because 11 of 12 normal cats vomited appropriately in response to xylazine (0.6 mg/kg, im) during the period of refractoriness to radiation

  17. Natural background radiation induces cytogenetic radioadaptive response more effectively than occupational exposure in human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Monfared, A.S.; Mozdarani, H.; Amiri, M.

    2003-01-01

    Ramsar, a city in the northern Iran, has the highest level of natural background radiation in the world. It has been clearly shown that low doses of ionising radiation can induce resistance to subsequent higher exposures. This phenomenon is termed radioadaptive response. We have compared induction of cytogenetic radioadaptive response by High Natural Background Radiation (HNBR) in Ramsar and X-ray occupational exposure as conditioning doses in human peripheral blood lymphocytes. 30 healthy control individuals, living in Ramsar but in normal background radiation areas, 15 healthy individuals from Talesh Mahalleh, a region with extraordinary high level of background radiation, and 7 X-ray radiographers working in Ramsar hospital located in normal natural background ionising radiation area were evaluated. Peripheral blood samples were prepared and exposed to challenge dose of 0 and 2 Gy. Lymphocytes were scored using analysis of metaphase, for the presence of chromosomal aberrations. An adaptive response was observed in HNBR and radiation workers groups in comparison with sham controls. A significant increase in adaptive response was observed in the HNBR group if compared with the occupationally exposed group. These findings indicate that both natural background radiation and occupational exposure could induce cytogenetic radioadaptive response and it is more significant regarding to natural background ionising radiation. (author)

  18. Effects of day-time exposure to different light intensities on light-induced melatonin suppression at night.

    Science.gov (United States)

    Kozaki, Tomoaki; Kubokawa, Ayaka; Taketomi, Ryunosuke; Hatae, Keisuke

    2015-07-04

    Bright nocturnal light has been known to suppress melatonin secretion. However, bright light exposure during the day-time might reduce light-induced melatonin suppression (LIMS) at night. The effective proportion of day-time light to night-time light is unclear; however, only a few studies on accurately controlling both day- and night-time conditions have been conducted. This study aims to evaluate the effect of different day-time light intensities on LIMS. Twelve male subjects between the ages of 19 and 23 years (mean ± S.D., 20.8 ± 1.1) gave informed consent to participate in this study. They were exposed to various light conditions (day-time light conditions). They were then exposed to bright light (300 lx) again between 01:00 and 02:30 (night-time light exposure). They provided saliva samples before (00:55) and after night-time light exposure (02:30). A one-tailed paired t test yielded significant decrements of melatonin concentration after night-time light exposure under day-time dim, 100- and 300-lx light conditions. No significant differences exist in melatonin concentration between pre- and post-night-time light exposure under day-time 900- and 2700-lx light conditions. Present findings suggest the amount of light exposure needed to prevent LIMS caused by ordinary nocturnal light in individuals who have a general life rhythm (sleep/wake schedule). These findings may be useful in implementing artificial light environments for humans in, for example, hospitals and underground shopping malls.

  19. Risk of Erectile Dysfunction Induced by Arsenic Exposure through Well Water Consumption in Taiwan

    Science.gov (United States)

    Hsieh, Fang-I; Hwang, Ti-Sheng; Hsieh, Yi-Chen; Lo, Hsiu-Chiung; Su, Chien-Tien; Hsu, Hui-Shing; Chiou, Hung-Yi; Chen, Chien-Jen

    2008-01-01

    Background Erectile dysfunction (ED) has a profound impact on the quality of life of many men. Many risk factors are associated with ED, such as aging, sex hormone levels, hypertension, cardiovascular diseases, and diabetes mellitus. Arsenic exposure could damage peripheral vessels and increase the risk of cardiovascular disease. However, the relationship between arsenic exposure and ED has seldom been evaluated. Objectives In this study we aimed to investigate whether exposure to arsenic enhances the risk of ED. Methods We recruited 177 males ≥ 50 years of age through health examinations conducted in three hospitals in Taiwan. We used a questionnaire (International Index of Erectile Function-5) to measure the level of erectile function. Sex hormones, including total testosterone and sex hormone–binding globulin, were determined by radioimmunoassay. We used another standardized questionnaire to collect background and behavioral information (e.g., cigarette smoking; alcohol, tea, or coffee drinking; and physical activity). Results The prevalence of ED was greater in the arsenic-endemic area (83.3%) than in the non–arsenic-endemic area (66.7%). Subjects with arsenic exposure > 50 ppb had a significantly higher risk of developing ED than those with exposure ≤ 50 ppb, after adjusting for age, cigarette smoking, diabetes mellitus, hypertension, and cardiovascular disease [odds ratio (OR) = 3.4]. Results also showed that the risk of developing severe ED was drastically enhanced by arsenic exposure (OR = 7.5), after adjusting for free testosterone and traditional risk factors of ED. Conclusions Results suggested that chronic arsenic exposure has a negative impact on erectile function. PMID:18414639

  20. Carbon black nanoparticle exposure during middle and late fetal development induces immune activation in male offspring mice

    International Nuclear Information System (INIS)

    El-Sayed, Yasser S.; Shimizu, Ryuhei; Onoda, Atsuto; Takeda, Ken; Umezawa, Masakazu

    2015-01-01

    Increasing exposure to nanoparticles (NPs) has raised concerns regarding their health and safety profiles in humans and animals, especially in developing organisms, which may display increased sensitivity to NP toxicity. The present study examined the effects of gestational exposure to carbon black NP (CB-NP) on the development of the offspring immune system. Pregnant mice were exposed to CB-NP (95 μg/kg body weight) by intranasal instillation on gestational days 9 and 15. The thymus and spleen were collected from their offspring mice on postnatal day (PND) 1, 3 and 5. Thymocyte and splenocyte phenotypes were examined by determining the expression of cell-surface molecules using flow cytometry. Gene expression in the thymus and spleen was examined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Prenatal exposure to CB-NP increased total thymocytes and their immunophenotypes (CD4 − CD8 − and CD4 + CD8 + cells). It also induced an increase in total lymphocytes, and CD4 − CD8 − , particularly CD3 − B220 − cells, at PND 5 in the spleen of newborn male offspring, reflecting the stimulation of immature splenocytes. Furthermore, mRNA expression of genes related to the induction of peripheral tolerance (i.e. thymic Traf6) was upregulated. These data suggest that respiratory exposure to CB-NP during middle and late gestation may have allergic or inflammatory effects in male offspring, and may provide initial information on the potential developmental immunotoxicity of nanoparticles

  1. Histone Deacetylase Inhibitor Induced Radiation Sensitization Effects on Human Cancer Cells after Photon and Hadron Radiation Exposure

    Directory of Open Access Journals (Sweden)

    Ariungerel Gerelchuluun

    2018-02-01

    Full Text Available Suberoylanilide hydroxamic acid (SAHA is a histone deacetylase inhibitor, which has been widely utilized throughout the cancer research field. SAHA-induced radiosensitization in normal human fibroblasts AG1522 and lung carcinoma cells A549 were evaluated with a combination of γ-rays, proton, and carbon ion exposure. Growth delay was observed in both cell lines during SAHA treatment; 2 μM SAHA treatment decreased clonogenicity and induced cell cycle block in G1 phase but 0.2 μM SAHA treatment did not show either of them. Low LET (Linear Energy Transfer irradiated A549 cells showed radiosensitization effects on cell killing in cycling and G1 phase with 0.2 or 2 μM SAHA pretreatment. In contrast, minimal sensitization was observed in normal human cells after low and high LET radiation exposure. The potentially lethal damage repair was not affected by SAHA treatment. SAHA treatment reduced the rate of γ-H2AX foci disappearance and suppressed RAD51 and RPA (Replication Protein A focus formation. Suppression of DNA double strand break repair by SAHA did not result in the differences of SAHA-induced radiosensitization between human cancer cells and normal cells. In conclusion, our results suggest SAHA treatment will sensitize cancer cells to low and high LET radiation with minimum effects to normal cells.

  2. Prenatal zinc prevents communication impairments and BDNF disturbance in a rat model of autism induced by prenatal lipopolysaccharide exposure.

    Science.gov (United States)

    Kirsten, Thiago B; Queiroz-Hazarbassanov, Nicolle; Bernardi, Maria M; Felicio, Luciano F

    2015-06-01

    Aims: Previous investigations by our group have shown that prenatal exposure to lipopolysaccharide (LPS),which mimics infections by Gram-negative bacteria, induced autistic-like behavior. No effective treatment yet exists for autism. Therefore, we used our rat model to test a possible treatment for autism.We selected zinc as the prenatal treatment to prevent or ease the impairments induced by LPS because LPS induces hypozincaemia.Materials and methods:We evaluated the effects of LPS and zinc on female reproductive performance. Communication,which is impaired in autism,was tested in pups by ultrasonic vocalizations. Plasma levels of brain-derived neurotrophic factor (BDNF) were determined because it has been considered an autism important biomarker.Key findings: Prenatal LPS exposure reduced offspring number and treatment with zinc prevented this reduction.Moreover, pups that were prenatally exposed to LPS spent longer periods without calling their mothers, and posttreatment with zinc prevented this impairment induced by LPS to the same levels as controls. Prenatal LPS also increased BDNF levels in adult offspring, and posttreatment with zinc reduced the elevation of BDNF to the same levels as controls.Significance: BDNF hyperactivity was also found in several studies of autistic patients. Together with our previous studies, our model of prenatal LPS induced autistic-like behavioral, brain, and immune disturbances. This suggests that it is a valid rat model of autism. Prenatal zinc prevented reproductive, communication, and BDNF impairments.The present study revealed a potential beneficial effect of prenatal zinc administration for the prevention of autism with regard to the BDNF pathway.

  3. Long-term nicotine exposure dampens LPS-induced nerve-mediated airway hyperreactivity in murine airways.

    Science.gov (United States)

    Xu, Yuan; Cardell, Lars-Olaf

    2017-09-01

    Nicotine is a major component of cigarette smoke. It causes addiction and is used clinically to aid smoke cessation. The aim of the present study is to investigate the effect of nicotine on lipopolysaccharide (LPS)-induced airway hyperreactivity (AHR) and to explore the potential involvement of neuronal mechanisms behind nicotine's effects in murine models in vivo and in vitro. BALB/c mice were exposed to nicotine in vivo via subcutaneous Alzet osmotic minipumps containing nicotine tartate salt solution (24 mg·kg -1 ·day -1 ) for 28 days. LPS (0.1 mg/ml, 20 µl) was administered intranasally for 3 consecutive days during the end of this period. Lung functions were measured with flexiVent. For the in vitro experiments, mice tracheae were organcultured with either nicotine (10 μM) or vehicle (DMSO, 0.1%) for 4 days. Contractile responses of the tracheal segments were measured in myographs following electric field stimulation (EFS; increasing frequencies of 0.2 to 12.8 Hz) before and after incubation with 10 µg/ml LPS for 1 h. Results showed that LPS induced AHR to methacholine in vivo and increased contractile responses to EFS in vitro. Interestingly, long-term nicotine exposure markedly dampened this LPS-induced AHR both in vitro and in vivo. Tetrodotoxin (TTX) inhibited LPS-induced AHR but did not further inhibit nicotine-suppressed AHR in vivo. In conclusion, long-term nicotine exposure dampened LPS-induced AHR. The effect of nicotine was mimicked by TTX, suggesting the involvement of neuronal mechanisms. This information might be used for evaluating the long-term effects of nicotine and further exploring of how tobacco products interact with bacterial airway infections. Copyright © 2017 the American Physiological Society.

  4. Pre- and postnatal exposure to low dose glufosinate ammonium induces autism-like phenotypes in mice.

    Science.gov (United States)

    Laugeray, Anthony; Herzine, Ameziane; Perche, Olivier; Hébert, Betty; Aguillon-Naury, Marine; Richard, Olivier; Menuet, Arnaud; Mazaud-Guittot, Séverine; Lesné, Laurianne; Briault, Sylvain; Jegou, Bernard; Pichon, Jacques; Montécot-Dubourg, Céline; Mortaud, Stéphane

    2014-01-01

    Glufosinate ammonium (GLA) is one of the most widely used herbicides in agriculture. As is the case for most pesticides, potential adverse effects of GLA have not been studied from the perspective of developmental neurotoxicity. Early pesticides exposure may weaken the basic structure of the developing brain and cause permanent changes leading to a wide range of lifelong effects on health and/or behavior. Here, we addressed the developmental impact of GLA by exposing female mice to low dose GLA during both pre- and postnatal periods and analyzed potential developmental and behavioral changes of the offspring during infancy and adulthood. A neurobehavioral test battery revealed significant effects of GLA maternal exposure on early reflex development, pup communication, affiliative behaviors, and preference for social olfactory cues, but emotional reactivity and emotional memory remained unaltered. These behavioral alterations showed a striking resemblance to changes seen in animal models of Autistic Spectrum Disorders. At the brain level, GLA maternal exposure caused some increase in relative brain weight of the offspring. In addition, reduced expression of Pten and Peg3 - two genes implicated in autism-like deficits - was observed in the brain of GLA-exposed pups at postnatal day 15. Our work thus provides new data on the link between pre- and postnatal exposure to the herbicide GLA and the onset of autism-like symptoms later in life. It also raises fundamental concerns about the ability of current safety testing to assess risks of pesticide exposure during critical developmental periods.

  5. Perinatal exposure to low dose glufosinate ammonium induces autism-like phenotypes in mice.

    Directory of Open Access Journals (Sweden)

    Anthony eLaugeray

    2014-11-01

    Full Text Available Glufosinate ammonium (GLA is one of the most widely used herbicides in agriculture. As is the case for most pesticides, potential adverse effects of GLA have not been studied from the perspective of developmental neurotoxicity. Early pesticides exposure may weaken the basic structure of the developing brain and cause permanent changes leading to a wide range of lifelong effects on health and/or behavior. Here we addressed the developmental impact of GLA by exposing female mice to low dose GLA during both pre- and postnatal periods and analyzed potential developmental and behavioral changes of the offspring during infancy and adulthood. A neurobehavioral test battery revealed significant effects of GLA maternal exposure on early reflex development, pup communication, affiliative behaviors, and preference for social olfactory cues, but emotional reactivity and emotional memory remained unaltered. These behavioral alterations showed a striking resemblance to changes seen in animal models of Autistic Spectrum Disorders. At the brain level, GLA maternal exposure caused some increase in normalized brain weight of the offspring. In addition, reduced expression of Pten and Peg3 - two genes implicated in autism-like deficits – was observed in the brain of GLA-exposed pups at postnatal day 15. Our work thus provides new data on the link between perinatal exposure to the herbicide GLA and the onset of autism-like symptoms later in life. It also raises fundamental concerns about the ability of current safety testing to assess risks of pesticide exposure during critical developmental periods.

  6. Mycorrhiza symbiosis increases the surface for sunlight capture in Medicago truncatula for better photosynthetic production.

    Directory of Open Access Journals (Sweden)

    Lisa Adolfsson

    Full Text Available Arbuscular mycorrhizal (AM fungi play a prominent role in plant nutrition by supplying mineral nutrients, particularly inorganic phosphate (Pi, and also constitute an important carbon sink. AM stimulates plant growth and development, but the underlying mechanisms are not well understood. In this study, Medicago truncatula plants were grown with Rhizophagus irregularis BEG141 inoculum (AM, mock inoculum (control or with P(i fertilization. We hypothesized that AM stimulates plant growth through either modifications of leaf anatomy or photosynthetic activity per leaf area. We investigated whether these effects are shared with P(i fertilization, and also assessed the relationship between levels of AM colonization and these effects. We found that increased P(i supply by either mycorrhization or fertilization led to improved shoot growth associated with increased nitrogen uptake and carbon assimilation. Both mycorrhized and P(i-fertilized plants had more and longer branches with larger and thicker leaves than the control plants, resulting in an increased photosynthetically active area. AM-specific effects were earlier appearance of the first growth axes and increased number of chloroplasts per cell section, since they were not induced by P(i fertilization. Photosynthetic activity per leaf area remained the same regardless of type of treatment. In conclusion, the increase in growth of mycorrhized and P(i-fertilized Medicago truncatula plants is linked to an increase in the surface for sunlight capture, hence increasing their photosynthetic production, rather than to an increase in the photosynthetic activity per leaf area.

  7. Mycorrhiza Symbiosis Increases the Surface for Sunlight Capture in Medicago truncatula for Better Photosynthetic Production

    Science.gov (United States)

    Adolfsson, Lisa; Keresztes, Áron; Uddling, Johan; Schoefs, Benoît; Spetea, Cornelia

    2015-01-01

    Arbuscular mycorrhizal (AM) fungi play a prominent role in plant nutrition by supplying mineral nutrients, particularly inorganic phosphate (Pi), and also constitute an important carbon sink. AM stimulates plant growth and development, but the underlying mechanisms are not well understood. In this study, Medicago truncatula plants were grown with Rhizophagus irregularis BEG141 inoculum (AM), mock inoculum (control) or with Pi fertilization. We hypothesized that AM stimulates plant growth through either modifications of leaf anatomy or photosynthetic activity per leaf area. We investigated whether these effects are shared with Pi fertilization, and also assessed the relationship between levels of AM colonization and these effects. We found that increased Pi supply by either mycorrhization or fertilization led to improved shoot growth associated with increased nitrogen uptake and carbon assimilation. Both mycorrhized and Pi-fertilized plants had more and longer branches with larger and thicker leaves than the control plants, resulting in an increased photosynthetically active area. AM-specific effects were earlier appearance of the first growth axes and increased number of chloroplasts per cell section, since they were not induced by Pi fertilization. Photosynthetic activity per leaf area remained the same regardless of type of treatment. In conclusion, the increase in growth of mycorrhized and Pi-fertilized Medicago truncatula plants is linked to an increase in the surface for sunlight capture, hence increasing their photosynthetic production, rather than to an increase in the photosynthetic activity per leaf area. PMID:25615871

  8. Bleaching of the thermoluminescence of feldspars by selected wavelengths present in sunlight

    International Nuclear Information System (INIS)

    Robertson, G.B.; Prescott, J.R.; Hutton, J.T.

    1993-01-01

    Feldspars occur in many sediments, and dating them by thermoluminescence (TL) requires a knowledge of how efficiently sunlight bleaches these minerals. The relative bleaching efficiencies of various wavelengths have been investigated for four alkali feldspars and an oligoclase, using the natural TL of the samples and the artificial TL induced by laboratory irradiation, bleached by wavelengths in the range 322-550 nm. Ultraviolet wavelengths are more efficient than the longer wavelengths at bleaching all the glow-curve peaks and are responsible for most of the phototransfer from high-temperature peaks to low-temperature peaks. Some feldspars show an initial increase in TL intensity with bleaching. Two sanidines of similar bulk composition but different TL glow curves show different dependences on bleaching wavelength. In a sodic sanidine with a dominant 240 o C peak the energy required to bleach to 50% was a thousand times greater at 550 nm than at 322 nm. In contrast, another sanidine with a complex glow curve between 150 and 450 o C showed a much slower change in the 330 o C peak with wavelength - a factor of 10 between 322 and 550 nm - with a region between 400 and 500 nm which was almost independent of wavelength. This behaviour is explained by competing mechanisms of phototransfer and bleaching which depend on wavelength in different ways. (author)

  9. Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling

    Energy Technology Data Exchange (ETDEWEB)

    Vuorinen, Terhi; Nerg, Anne-Marja; Holopainen, Jarmo K

    2004-09-01

    We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-{beta}-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation.

  10. Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling

    International Nuclear Information System (INIS)

    Vuorinen, Terhi; Nerg, Anne-Marja; Holopainen, Jarmo K.

    2004-01-01

    We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-β-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation

  11. Statins attenuate the development of atherosclerosis and endothelial dysfunction induced by exposure to urban particulate matter (PM{sub 10})

    Energy Technology Data Exchange (ETDEWEB)

    Miyata, Ryohei; Hiraiwa, Kunihiko; Cheng, Jui Chih [UBC James Hogg Research Centre, St. Paul' s Hospital, University of British Columbia, Vancouver (Canada); Bai, Ni [UBC James Hogg Research Centre, St. Paul' s Hospital, University of British Columbia, Vancouver (Canada); Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver (Canada); Vincent, Renaud [Environmental Health Sciences and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa (Canada); Francis, Gordon A.; Sin, Don D. [UBC James Hogg Research Centre, St. Paul' s Hospital, University of British Columbia, Vancouver (Canada); Van Eeden, Stephan F., E-mail: Stephan.vanEeden@hli.ubc.ca [UBC James Hogg Research Centre, St. Paul' s Hospital, University of British Columbia, Vancouver (Canada)

    2013-10-01

    Exposure to ambient air particulate matter (particles less than 10 μm or PM{sub 10}) has been shown to be an independent risk factor for the development and progression of atherosclerosis. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have well-established anti-inflammatory properties. The aim of this study was to determine the impact of statins on the adverse functional and morphological changes in blood vessels induced by PM{sub 10}. New Zealand White rabbits fed with a high fat diet were subjected to balloon injury to their abdominal aorta followed by PM{sub 10}/saline exposure for 4 weeks ± lovastatin (5 mg/kg/day) treatment. PM{sub 10} exposure accelerated balloon catheter induced plaque formation and increased intimal macrophages and lipid accumulation while lovastatin attenuated these changes and promoted smooth muscle cell recruitment into plaques. PM{sub 10} impaired vascular acetylcholine (Ach) responses and increased vasoconstriction induced by phenylephrine as assessed by wire myograph. Supplementation of nitric oxide improved the impaired Ach responses. PM{sub 10} increased the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in blood vessels and increased the plasma levels of endothelin-1 (ET-1). Incubation with specific inhibitors for iNOS, COX-2 or ET-1 in the myograph chambers significantly improved the impaired vascular function. Lovastatin decreased the expression of these mediators in atherosclerotic lesions and improved endothelial dysfunction. However, lovastatin was unable to reduce blood lipid levels to the baseline level in rabbits exposed to PM{sub 10}. Taken together, statins protect against PM{sub 10}-induced cardiovascular disease by reducing atherosclerosis and improving endothelial function via their anti-inflammatory properties. - Highlights: • Coarse particulate matter (PM{sub 10}) accelerated balloon injury-induced plaque formation. • Lovastatin decreased intimal

  12. Statins attenuate the development of atherosclerosis and endothelial dysfunction induced by exposure to urban particulate matter (PM10)

    International Nuclear Information System (INIS)

    Miyata, Ryohei; Hiraiwa, Kunihiko; Cheng, Jui Chih; Bai, Ni; Vincent, Renaud; Francis, Gordon A.; Sin, Don D.; Van Eeden, Stephan F.

    2013-01-01

    Exposure to ambient air particulate matter (particles less than 10 μm or PM 10 ) has been shown to be an independent risk factor for the development and progression of atherosclerosis. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have well-established anti-inflammatory properties. The aim of this study was to determine the impact of statins on the adverse functional and morphological changes in blood vessels induced by PM 10 . New Zealand White rabbits fed with a high fat diet were subjected to balloon injury to their abdominal aorta followed by PM 10 /saline exposure for 4 weeks ± lovastatin (5 mg/kg/day) treatment. PM 10 exposure accelerated balloon catheter induced plaque formation and increased intimal macrophages and lipid accumulation while lovastatin attenuated these changes and promoted smooth muscle cell recruitment into plaques. PM 10 impaired vascular acetylcholine (Ach) responses and increased vasoconstriction induced by phenylephrine as assessed by wire myograph. Supplementation of nitric oxide improved the impaired Ach responses. PM 10 increased the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in blood vessels and increased the plasma levels of endothelin-1 (ET-1). Incubation with specific inhibitors for iNOS, COX-2 or ET-1 in the myograph chambers significantly improved the impaired vascular function. Lovastatin decreased the expression of these mediators in atherosclerotic lesions and improved endothelial dysfunction. However, lovastatin was unable to reduce blood lipid levels to the baseline level in rabbits exposed to PM 10 . Taken together, statins protect against PM 10 -induced cardiovascular disease by reducing atherosclerosis and improving endothelial function via their anti-inflammatory properties. - Highlights: • Coarse particulate matter (PM 10 ) accelerated balloon injury-induced plaque formation. • Lovastatin decreased intimal macrophages, lipid accumulation, and

  13. Surfactant and natural sunlight enhanced Photogalvanic effect of Sudan I dye

    Directory of Open Access Journals (Sweden)

    Pooran Koli

    2017-12-01

    Full Text Available Photogalvanic cells (PG have been extensively studied for solar power and storage at low intensity artificial sunlight. But, PG can be practically significant and applicable in daily life only when they are validated at natural sunlight intensity. Therefore, the present study of photogalvanics of Sudan I-Fructose with efficiency enhancer chemical such as Sodium Lauryl Sulfate (SLS surfactant in alkaline medium has been used to observe their workable feasibility in natural sunlight with investigation for optimal fabrication parameters. The cell has been found workable in natural sunlight with greatly enhanced optimum cell performance compared to that for reported similar cells. The observed optimum cell performance in terms of maximum power, short-circuit current, open-circuit potential, conversion efficiency and storage capacity (as half change time is of the order of 1081.1 μW, 4200 μA, 1048 mV, 13.5%, and 31 min, respectively.

  14. Hyperconnectivity of local neocortical microcircuitry induced by prenatal exposure to valproic acid

    DEFF Research Database (Denmark)

    Rinaldi, Tania; Silberberg, Gilad; Markram, Henry

    2008-01-01

    Exposure to valproic acid (VPA) during embryogenesis can cause several teratogenic effects, including developmental delays and in particular autism in humans if exposure occurs during the third week of gestation. We examined the postnatal effects of embryonic exposure to VPA on microcircuit...... properties of juvenile rat neocortex using in vitro electrophysiology. We found that a single prenatal injection of VPA on embryonic day 11.5 causes a significant enhancement of the local recurrent connectivity formed by neocortical pyramidal neurons. The study of the biophysical properties...... of these connections revealed weaker excitatory synaptic responses. A marked decrease of the intrinsic excitability of pyramidal neurons was also observed. Furthermore, we demonstrate a diminished number of putative synaptic contacts in connection between layer 5 pyramidal neurons. Local hyperconnectivity may render...

  15. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB

    OpenAIRE

    Sun, Bao-Fei; Wang, Qing-Qing; Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dos...

  16. Exposure to Ultrafine Particles from Ambient Air and Oxidative Stress-Induced DNA Damage

    DEFF Research Database (Denmark)

    Bräuner, Elvira Vaclavik; Forchhammer, Lykke; Møller, Peter

    2007-01-01

    mononuclear cells (PBMCs) during controlled exposure to urban air particles with assignment of number concentration (NC) to four size modes with average diameters of 12, 23, 57, and 212 nm. DESIGN. Twenty-nine healthy adults participated in a randomized, two-factor cross-over study with or without biking...... exercise for 180 min and with exposure to particles (NC 6169-15362/cm3) or filtered air (NC 91-542/cm3) for 24 hr. METHODS: The levels of DNA strand breaks (SBs), oxidized purines as formamidopyrimidine DNA glycolase (FPG) sites, and activity of 7,8-dihydro-8-oxoguanine-DNA glycosylase (OGG1) in PBMCs were...

  17. Natural Sunlight Shapes Crude Oil-Degrading Bacterial Communities in Northern Gulf of Mexico Surface Waters

    OpenAIRE

    Bacosa, Hernando P.; Liu, Zhanfei; Erdner, Deana L.

    2015-01-01

    Following the Deepwater Horizon (DWH) spill in 2010, an enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico. Surface waters are characterized by intense sunlight and high temperature during sum