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The antitumor protein, neocarzinostatin, has been crystallized and examined by X-ray diffraction. Crystals of this globular protein are of space group P212121 with cell parameters a = 27.4Å, b = 33.9Åand c = 102.0Å. There is one molecule of approximately 27Ådiameter per asymmetric unit. Crystals soaked in a K2HgI4 solution give diffraction patterns significantly different from native crystal diffraction patterns.  相似文献   

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This research examined the quality of water-before and after distribution-of four drinking-water production plants located in Northern Italy, two of which collected water from local aquifers and two from the River Po. A battery of genotoxicity assays for monitoring drinking-water was performed to assess the quality of the water produced by the treatment plants under study. Three different sampling stations were selected at each plant, one right at the outlet of the treatment plant and two along with the distribution pipelines. Raw river water was also sampled and analysed as a control. The water samples (500 l) were concentrated on silica C18 cartridges and the extracts were tested in in vitro mutagenicity assays (Salmonella/microsome assay with strains TA 98 and TA 100; SOS Chromotest with Escherichia coli strain PQ37); gene conversion, point mutation and mitochondrial DNA mutability assays with the diploid Saccharomyces cerevisiae strain D7 and a toxicity test using the bioluminescent bacterium Vibrio fischeri (Microtox). The Microtox test and the mitochondrial DNA mutability assay showed the greatest sensitivity towards toxic or mutagenic substances in the water extracts considered. The results show that this battery of short-term tests is applicable in the routine monitoring of drinking-water quality before and after distribution.  相似文献   

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The extract of K. pinnata was evaluated for its wound healing activity by using excision wound model in rats. On day 11, animals treated with the ethanolic leaf extract exhibited 86.33% reduction in the wound area, compared to petroleum jelly treated control (69.36%) and the mupirocin treated standard (85.49%). The hydroxyproline content of extract treated animals was higher, as compared to control and the standard groups. Histological analysis was also consistent with the proposal that K. pinnata leaf extract exhibits significant wound healing potential. The increased rate of wound contraction and hydroxyproline content in the extract treated animals supports the claims made by traditional healers of the benefits obtained from the medicinal use of K. pinnata.  相似文献   

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A chloroform crude extract of whole Arthrospira platensis cells, provisionally named A. platensis auto-inhibitor (APAI), was inhibitory to growth of human prostatic cells and was toxic to them at less than 25 g/ml. With cultured protoplasts of Petunia hybrida, APAI was growth inhibitory, without cytotoxicity, at 500 g/ml. Using flow cytometry, it was seen that APAI induced arrest of the plant cell division cycle at the G1 phase. © Rapid Science Ltd. 1998  相似文献   

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Creosote and coal tar were examined for the presence of volatile mutagens by use of the so-called "taped plate assay". Application of this method, recently published by Distlerath et al., reveals that vapour escaping from creosote and coal tar at 37 degrees C was able to revert the Salmonella typhimurium strains TA98 and TA100 in the presence of S9 mix. The simplicity of this method makes it useful for routine screening of industrial fluids or solid products for the presence of volatile mutagens.  相似文献   

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Movile Cave, a unique groundwater ecosystem in southern Romania, was discovered in 1986. This chemoautotrophic cave contains an abundant and diverse fauna with terrestrial and aquatic invertebrate communities, including 33 endemic species. Since its discovery, studies have focused mainly on cave chemoautotrophic bacteria, while the microfungal community has been largely neglected. In this study, we determined the microfungal species living on various substrates in Movile Cave and compared this spectrum with the mycobiota detected outside the cave (outside air-borne and soil-borne microfungi). To investigate all of the niches, we collected samples for two consecutive years from the dry part of the cave (cave air and sediment, corroded limestone walls, isopod feces, and isopod and spider cadavers) and from the post-siphon part of the cave, i.e., Airbell II (sediment and floating microbial mat). A total of 123 microfungal species were identified from among several hundred isolates. Of these, 96 species were only detected in the cave environment and not outside of the cave, while 90 species were from the dry part of the cave and 28 were from Airbell II. The most diverse genera were Penicillium (at least 18 species) and Aspergillus (14 species), followed by Cladosporium (9 species). Surprisingly, high CFU counts of air-borne microfungi were found inside the cave; they were even higher than outside the cave during the first year of investigation.  相似文献   

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The aim of this study was to determine the degree to which socioeconomic status is a risk factor for first birth at age 19 or younger in married women in an urban area of Turkey. The research was a population-based case-control study. The study group comprised all married and pregnant women aged 15-19 (adolescent pregnancies) attending primary care centres (144 subjects). Married women between 20 and 29 years of age, experiencing their first pregnancy (adult pregnancies), were determined as the control group (144 subjects). A questionnaire was completed for each subject during face-to-face interviews. Adolescent pregnancy was more frequent in women from families with a low socioeconomic status, as determined by occupation (class) and income; both were associated with adolescent pregnancy. Multiple logistic regression analysis identified seven factors associated with adolescent pregnancy: exposure to violence within the family prior to marriage; families partially opposed or unopposed to adolescent marriage; secondary school or lower education level; lack of social security; living in houses in which the number of persons per room was over 1; unemployed women; and having sisters with a history of adolescent pregnancy.  相似文献   

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Forty-one fungal isolates (one isolate per species) representing common plant pathogens and food crop contaminants were grown on sterile, polished rice and assayed for mutagenic activity in the Salmonella typhimurium-microsome system. Initially, single doses of aqueous and chloroform extracts of the moldy rice were assayed against the TA100 tester strain by incorporating extracts into the growth medium and by applying small quantities on disks placed on the agar surface. Suspected activity was examined further by analysis of several doses in the plate incorporation assay. Extracts of two aflatoxin-producing isolates (Aspergillus flavus and A. parasiticus) showed pronounced mutagenic activity, as did extracts of five other isolates (A. heterothallicus, A. nidulans, A. terricola, Alternaria tenuis, and Fusarium moniliforme) which did not contain detectable aflatoxins. Seven additional isolates (Botrytis cineria, Ceratocystis fimbriata, Cladosporium herbarum, Fusarium solani f. sp. pisi, Penicillium oxalicum, Thermomyces lanuginosus, and Verticilium albo-atrum) revealed activity which was possibly mutagenic; i.e., mutagenic responses were not observed in both the disk and incorporation assays, and clear dose-related activity was not observed in the incorporation assay. Extracts of the remaining fungi were not mutagenic in the bacterial assay.  相似文献   

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Forty-one fungal isolates (one isolate per species) representing common plant pathogens and food crop contaminants were grown on sterile, polished rice and assayed for mutagenic activity in the Salmonella typhimurium-microsome system. Initially, single doses of aqueous and chloroform extracts of the moldy rice were assayed against the TA100 tester strain by incorporating extracts into the growth medium and by applying small quantities on disks placed on the agar surface. Suspected activity was examined further by analysis of several doses in the plate incorporation assay. Extracts of two aflatoxin-producing isolates (Aspergillus flavus and A. parasiticus) showed pronounced mutagenic activity, as did extracts of five other isolates (A. heterothallicus, A. nidulans, A. terricola, Alternaria tenuis, and Fusarium moniliforme) which did not contain detectable aflatoxins. Seven additional isolates (Botrytis cineria, Ceratocystis fimbriata, Cladosporium herbarum, Fusarium solani f. sp. pisi, Penicillium oxalicum, Thermomyces lanuginosus, and Verticilium albo-atrum) revealed activity which was possibly mutagenic; i.e., mutagenic responses were not observed in both the disk and incorporation assays, and clear dose-related activity was not observed in the incorporation assay. Extracts of the remaining fungi were not mutagenic in the bacterial assay.  相似文献   

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Summer bioclimatic discomfort is a significant public health problem. Bioclimatic characterisations of populations living in urban areas are usually very poor, although the risks are relatively higher in cities because of the phenomenon known as the “urban heat island”. We compared airport, rural, and urban bioclimatic conditions in terms of apparent temperature, Thom index, and temperature alone in several sites within a radius of approximately 25 km from the city of Bologna (Italy). The comparison between meteorological monitoring stations within and near the urban area showed the large impact of the urban heat island effect. Nighttime data showed the largest differences among the investigated sites. Minimum apparent temperatures at rural stations were about 3.5°C lower than the urban 30 m reference station, and 6°C lower than the 2 m urban site. The 2 m apparent temperature values within the urban area were several degrees higher (typically 2°C) than those taken above the roof, both for minimum and maximum values. Temporal trends in the different sites were highly correlated (generally above 0.90), but regression residuals were sometimes quite large. Finally, epidemiological implications are briefly addressed.  相似文献   

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This work presents the results of the study of airborne bacteria in a kindergarten in Gliwice, Upper Silesia, Poland. In this study, the samples of bioaerosols were collected using six-stage Andersen cascade impactor (with aerodynamic cutoff diameters 7.0, 4.7, 3.3, 2.1, 1.1, and 0.65 μm). The level of culturable bacterial aerosols indoors was about 3000 CFU m?3—six to eight times higher than outdoors. In the classrooms, respirable bacterial particles, <4.7 µm, contributed up to 85 % of the total number of culturable bacteria, increasing the possible adverse health effects due to their inhalation. The identification of the bacterial species showing the dominance of gram-positive cocci in the indoor environment and non-sporing gram-positive rods in the outdoor air indicates that most of the bacteria present in the studied kindergarten are human origin. Using the obtained data, the nursery school exposure dose (NSED) of bioaerosols was estimated for the children and personnel of this kindergarten (nursery school). The highest value of NSED was obtained for younger children (930 CFU kg?1) compared to older children (about 600 CFU kg?1) and to the kindergarten staff (about 300 CFU kg?1). This result suggests the elevated risk of adverse health effects in younger children exposed to the bioaerosols in the kindergarten, including infections.  相似文献   

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A monoclonal antibody (mAb KT4), produced against a Pichia anomala killer toxin, was used to study the secretion process of toxin producing cells. The indirect immunofluorescence assay, performed with large concentrations of mAb KT4, showed a homogeneous distribution of the epitope at the cell surface of the P anomala cells. When increasing dilutions of mAb KT4 were employed, a 'punctuated' labeling appeared on the yeast's cell wall which suggested a heterogeneous secretion of the killer toxin. Similar labeling was also observed by immunodetection on live yeast cells held in buffered suspension. These results confirmed that 'punctuated' labeling was not an artefact due to a distortion of the cell's shape by having been dried on glass slides. Indirect immunodetection was performed in electron microscopy on ultra-thin sections of cells embedded in Araldite resin. The labeling thus obtained showed both the presence of the epitope in the cytoplasm and its sensitivity to strong glutaraldehyde fixation. Indirect immunodetection, performed on ultra-thin frozen sections, showed a cytoplasmic and cell wall labelling. However, the amount of gold particles observed in the cell wall was too low to confirm the heterogeneous killer toxin secretion observed in immunofluorescence. In this case, killer cells were fixed with a low concentration of glutaraldehyde which preserved the structure of the epitope complementary with mAb KT4.  相似文献   

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The prevalence of obesity has been rising alarmingly and it has now become a global concern causing an enormous economic burden on the health care system. Obesity is generally linked to complications in lipid metabolism and oxidative stress. The aim of the present study was to investigate the effect of rosuvastatin (10 mg/kg, po) on obesity-induced oxidative stress in high fat-fed Wistar rats. Oral administration of rosuvastatin (10 mg/kg) for 21 days along with high fat diet brought about significant elevation in serum high density lipoprotein and cardiac antioxidant enzymes levels (superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione peroxidase-, glutathione reductase- and glutathione-S-transferase) while decreasing in serum lactate dehydrogenase, apolipoprotein-B, lipids (triglycerides, total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and atherogenic index) and cardiac thiobarbituric acid reactive substances levels. The results were comparable with orlistat, a standard antiobesity drug. These preliminary results for the first time demonstrate that administration of rosuvastatin can be beneficial for the suppression of obesity-induced oxidative stress and dyslipidemia in high fat-fed Wistar rats.  相似文献   

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