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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology letters 192 (2000), S. 0 
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: We investigated the mechanism of the oxidative DNA damage induction by exposure to O2 in Prevotella melaninogenica, a strict anaerobe. Flow cytometry with hydroethidine and dichlorofluorescein diacetate showed that O2 exposure generated O2•− and H2O2. Results of electron spin resonance with α-(4-pyridyl-1-oxide)-N-tert-butylnitrone and ethanol showed that O2 exposure also induced •OH radical generation in P. melaninogenica loaded with FeCl2 but not in samples without FeCl2 loading. In P. melaninogenica, O2 exposure increased 8-hydroxydeoxyguanosine (8OHdG), typical of oxidative DNA damage. Catalase inhibited the increase, but the •OH radical scavengers did not. Phenanthroline, a membrane-permeable Fe and Cu chelator, increased the 8OHdG induction. In FeCl2-loaded samples, induction of 8OHdG decreased. Addition of H2O2 markedly increased 8OHdG levels. These results indicate that in P. melaninogenica, exposure to O2 generated and accumulated O2•− and H2O2, and that a crypto-OH radical generated through H2O2 was the active species in the 8OHdG induction.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1600-051X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aim: This study attempted to determine the relationship between passive and active smoking on the basis of salivary cotinine levels and periodontitis severity.Methods: Japanese workers (n=273) were surveyed via an oral examination, a self-administered questionnaire and collection of whole saliva. Probing pocket depth (PPD) and clinical attachment level (CAL) served as periodontal parameters. Periodontitis was defined as the presence of two or more teeth with PPD 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE819:ges" location="ges.gif"/〉3.5 mm and CAL 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE819:ges" location="ges.gif"/〉3.5 mm. Salivary cotinine was determined using ELISA. Statistical methods included Wilcoxon's rank-sum test and multiple logistic regression analysis.Results: Based on the results of receiver-operating characteristic plots for cotinine-level classification derived from self-reported smoking status, non-, passive and active smokers were defined as those subjects exhibiting cotinine levels of 0, 1–7 and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE819:ges" location="ges.gif"/〉8 ng/ml, respectively. Numbers of teeth displaying CAL 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE819:ges" location="ges.gif"/〉3.5 mm in passive and active smokers were significantly higher than those in non-smokers. Multiple logistic regression analysis revealed significantly higher periodontitis odds ratios in passive and active smokers relative to non-smokers following adjustment for other lifestyle factors; odds ratios were 2.87 [95% confidence interval (CI); 1.05–7.82] and 4.91 (95% CI; 1.80–13.35), respectively.Conclusion: These findings suggest that passive smoking classified in terms of salivary cotinine level may be an independent periodontitis risk indicator.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 288 (1980), S. 604-606 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] PHA-stimulated human lymphocytes were cultured in medium containing BUdR so that cells dividing for the first, second and third time after initiation of culture could be distinguished by the differential staining pattern of sister chromatids in slides stained with fluorescence-plus-Giemsa (FPG)20. ...
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    International archives of occupational and environmental health 61 (1989), S. 426-426 
    ISSN: 1432-1246
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-1246
    Keywords: Benzene ; Chromosome ; Genotoxicity ; Lifestyle ; Repair
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Short-term cultures of human lymphocytes were used to investigate the in vitro metabolism of benzene and its genotoxicity, and to monitor genetic health effects of lifestyles. Metabolic (S9) activation of benzene and its metabolites, catechol, hydroquinone, and phenol, caused an increase in sister-chromatid exchanges (SCEs) with different optimal concentrations of S9 mix for converting each compound into further reactive forms. The data indicate that catechol and hydroquinone can be optimally metabolized to produce reactive species, presumably benzo(semi)quinones, under conditions of lower metabolic activity than those necessary for phenol and benzene. We have further investigated the correlations between chromosome alterations (SCEs, structural aberrations and micronuclei) in peripheral lymphocytes and individual lifestyles. Healthy lifestyles, or “good health practices” examined were 1) not smoking, 2) not drinking too much alcohol, 3) doing physical exercise regularly, 4) sleeping more than 6 h per night, 5) keeping nutritional balance in meals, 6) not snacking, 7) having breakfast everyday, and 8) not having too much perceived stress. The persons were categorized into 3 groups having good, moderate and poor lifestyles by the number of good health practices they do. Mean frequencies of chromosome alterations in lymphocytes from men with poor lifestyles have been shown to be significantly higher than those in cells from men having good lifestyles. Further experiments have been done to examine whether lymphocytes from men having unhealthy lifestyles might show a higher susceptibility 1) to the SCE production by treatment with hydroquinone, a major metabolite of benzene, and 2) to the chemical's inhibitory effect of repair of radiation-induced chromosome breakage, because our living and working environments contain possible repair inhibitors such as benzene, lead and chromium. The results showed that unhealthy lifestyles could make the cells to be more sensitive to the production of these chromosome alterations by the environmental and occupational agents.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Human genetics 〈Berlin〉 106 (2000), S. 589-593 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. A highly prevalent, atypical genotype in low Km aldehyde dehydrogenase (ALDH2) may influence alcohol-induced liver injury because of higher production of acetaldehyde in the liver. In the present study, we examined relationships between the ALDH2 genotype, alcohol intake, and liver-function biomarkers among Japanese male workers. Study subjects were 385 male workers in a metal plant in Japan, who were free from hepatic viruses and did not have higher aminotransferase activities (〈100). The subjects completed a questionnaire on alcohol drinking habits and other lifestyles. The ALDH2 genotype was determined by the PCR method followed by restriction-enzyme digestion. In the moderately and heavily drinking groups, those with ALDH2*1/*2 exhibited significantly lower levels than those with ALDH2*1/*1 for all three parameters of liver function, whereas no such differences were observed in the least-drinking group. Multiple linear-regression analysis, adjusting for age, obesity, and smoking habits, revealed that aspartate aminotransferase activity was positively associated with alcohol intake only in those with ALDH2*1/*1. On the other hand, alanine transferase activity was negatively associated with alcohol intake only in those with ALDH2*1/*2. The present study indicates that effects of alcohol intake on liver-function biomarkers are likely to be modified by the ALDH2 genotype in adult males.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Human genetics 〈Berlin〉 63 (1983), S. 19-23 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Lymphocytes from two sisters with Fanconi's anemia (FA) were studied for cell cycle kinetics, sister chromatid exchanges (SCEs), and chromosomal aberrations when they had undergone one, two, or three or more divisions in mitomycin C (MMC)-treated cultures. Lymphocytes from the parents another sister of the probands, and a healthy unrelated adult were examined as controls. Analyses of cell cycle kinetics by the sister chromatid differential staining method revealed that the relative frequency of metaphase cells at their third or subsequent divisions was much smaller in untreated FA cultures than in normal cultures fixed at 96h after phytohemagglutinin stimulation. These data indicate that FA cells proliferate much more slowly than normal cells. MMC treatments of FA and normal cells led to a clearly dose-related delay in cell turnover times, the duration of delay being much longer in FA than in normal cells. FA cells had about 1.4 times higher frequencies of SCEs than normal cells in both MMC-treated and untreated cultures. FA cells also showed several times higher frequencies of chromosomal aberrations than normal cells, and the frequency of chromosomal aberrations decreased through subsequent mitoses by approximately 60% in both FA and normal cells.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    International archives of occupational and environmental health 72 (1999), S. 14-18 
    ISSN: 1432-1246
    Keywords: Key words Methyltetrahydrophthalic anhydride ; Rhinitis ; Conjunctivitis ; Specific IgE ; Exposure-response relationship
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Objective: To examine exposure-response relationships in the occurrence of symptoms of the eyes and airways in workers exposed to methyltetrahydrophthalic anhydride (MTHPA). Methods: A population of 111 workers from 2 condenser plants (A and B) using epoxy resin with MTHPA underwent a questionnaire survey and serology investigations, and data obtained on 95 subjects in assembly and inspection lines were analyzed for this study. Results: In all, 24 (65%) of 37 workers in plant A and 38 (66%) of 58 workers in plant B had positive MTHPA-specific IgE. The air levels of MTHPA detected in assembly and inspection lines were higher in plant A than in plant B (geometric mean 25.5–63.9  and 4.93–5.49 μg/m3, respectively). IgE-sensitized workers in each plant had significantly (P 〈 0.05) more complaints regarding the eyes and nose than did unsensitized workers, suggesting that there is an IgE-mediated mechanism in most of these symptoms. The sensitized workers in plant A had higher frequencies for symptoms of the eyes, nose, and pharynx than did those in plant B (P 〈 0.02). Furthermore, only 15% of persons often displayed work-related symptoms among the 20 symptomatic workers in plant B as compared with 73% of the 26 symptomatic workers in plant A (P 〈 0.0001). These results can be explained by the difference in the MTHPA levels measured in the lines between the two plants. In plant B the minimal level of MTHPA that was associated with work-related symptoms was 15–22 μg/m3, which was lower than the geometric mean levels detected in assembly and inspection lines in plant A. Conclusions: These results suggest that MTHPA exposure at levels above 15 μg/m3 should be avoided to prevent the development of occupational allergic diseases in most workers.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract A deficiency in low Km aldehyde dehydrogenase (ALDH2) is regarded as the main factor responsible for “Oriental flushing” and other symptoms due to alcohol sensitivity. In this study, the relationship of the ALDH2 genotype to alcohol-associated symptoms and drinking behavior was investigated in 524 Japanese workers, using a new, rapid, and nonisotopic polymerase chain reaction (PCR) method. Differences in the frequency of alcohol-associated manifestations between the normal homozygote and the other deficient types were apparent. In addition, among the ALDH2-deficient individuals, the atypical homozygote was obviously more hypersensitive to alcohol than the heterozygote, judging from the frequency of flushing or other drinking-associated manifestations with a small dose of alcohol. Drinking frequency also apparently decreased in the following order: typical homozygote, heterozygote, atypical homozygote. Similarly, mean amounts of alcohol consumption also decreased in the same order, although considerable variation existed within the typical homozygote and the heterozygote group. In contrast, neither the manifestations nor the drinking behavior were, in general, influenced by polymorphism of the alcohol dehydrogenase β-subunit (ADH2) gene in males. These findings further indicate the important contribution of the ALDH2 genotype to alcohol sensitivity in Orientals.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In humans, ingested alcohol is mainly metabolized by the combination of class I alcohol dehydrogenase (ADII) and aldehyde dehydrogenase (ALDH). In Orientals, there are highly frequent polymorphisms both in the class I ADH β subunit (ADHZ) and in the low Km ALDH (ALDH2). We characterized the three genotypes of ALDH2 in a Japanese population. In the present study, we evaluated the effects of the ADH2 polymorphism in the same population (424 males and 100 females) controlling for the effects of the ALDH2 polymorphism. In the ALDH21/ALDH22 group, the frequency of facial flushing with one glass of beer was significantly higher in the ADH2 1/ADH2 2 and ADH2 2/ADH2 2 genotype than in the ADH2 1/ADH2 1 genotype. Likewise, the proportion of persons with positive results for ethanol-induced cutaneous erythema differed significantly depending on the ADH2 genotype in both the ALDH21/ALDH21 and ALDH21/ALDH22 genotypes. However, drinking habits were not significantly associated with the ADH2 genotype, suggesting that the ADH2 genotype influences the metabolism of ethanol only in the peripheral tissues.
    Type of Medium: Electronic Resource
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