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121.
122.
Maria Benitez‐Guijarro Cesar Lopez‐Ruiz Žygimantė Tarnauskaitė Olga Murina Mahwish Mian Mohammad Thomas C Williams Adeline Fluteau Laura Sanchez Raquel Vilar‐Astasio Marta Garcia‐Canadas David Cano Marie‐Jeanne HC Kempen Antonio Sanchez‐Pozo Sara R Heras Andrew P Jackson Martin AM Reijns Jose L Garcia‐Perez 《The EMBO journal》2018,37(15)
123.
AflatoxigenicAspergillus flavus andAspergillus parasiticus were subjected to solid substrate fermentation process for 6 days to determine the formation of aflatoxins and production
of extracellular enzymes (amyloglucosidase, cellulase, invertase and proteinase). Both organisms produced enzymes which generally
increased with fermentation.Aspergillus flavus produced four enzymes whereasA. parasiticus produced three with no proteinase activity.Aspergillus parasiticus produced aflatoxins B1, B2 and G1 but no G2 andA. flavus produced aflatoxins B1 and B2. Invertase showed the highest activity withA. parasiticus and that corresponded with the highest total toxin produced. The enzyme activities were higher withA. parasiticus thanA. flavus although total toxins produced byA. parasiticus were lower than total toxins produced byA. flavus under the same environmental conditions. 相似文献
124.
A survey was done to find microorganisms useful for assaying sterigmatocystin; T-2 toxin and zearalenone.Staphylococcus aureus was found to be sensitive to T-2 toxin and zearalenone;Bacillus cereus was found to be sensitive to T-2 toxin only; andEscherichia coli was sensitive to sterigmatocystin. The response of the organisms to sterigmatocystin; T-2 toxin and zearalenone was found to be linear between 4 and 100 μg with sterigmatocystin toE. coli; between 2 and 25 μg with T-2 toxin toStaph, aureus andB. cereus; and between 4 and 100 μg with zearalenone toStaph, aureus. The lower limits of sensitivity of the test were 2 μg T-2 toxin and zearalenone, and 4 μg sterigmatocystin. The assay is rapid (15–17 hrs); simple and inexpensive; and can be used to verify the toxicity of samples and to confirm thin layer chromatographic results. 相似文献
125.
Thymol and Carvacrol Prevent Cisplatin‐Induced Nephrotoxicity by Abrogation of Oxidative Stress,Inflammation, and Apoptosis in Rats 下载免费PDF全文
El‐Sayed EM Abd‐Allah AR Mansour AM EL‐Arabey AA 《Journal of biochemical and molecular toxicology》2015,29(4):165-172
The aim of the present study is to assess the possible protective effects of thymol and carvacrol against cisplatin (CP)‐induced nephrotoxicity. A single dose of CP {6 mg/kg, intraperitoneally (i.p.)} injected to male rats revealed significant increases in serum urea, creatinine, and tumor necrosis factor alpha levels. It also increased kidney contents of malondialdehyde and caspase‐3 activity with significant reduction in serum albumin, kidney content of reduced glutathione as well as catalase, and superoxide dismutase activity as compared to that of the control group. In contrast, administration of thymol {20 mg/kg, orally (p.o.)} and/or carvacrol (15 mg/kg, p.o.) for 14 days before CP injection and for 7 days after CP administration restored the kidney function and examined oxidative stress parameters. In conclusion, thymol was more effective nephroprotective than carvacrol. Moreover, a combination of thymol and carvacrol had a synergistic nephroprotective effect that might be attributed to antioxidant, anti‐inflammatory, and antiapoptotic activities. 相似文献
126.
Wytske A Altenburg Marieke L Duiverman Nick HT ten Hacken Huib AM Kerstjens Mathieu HG de Greef Peter J Wijkstra Johan B Wempe 《Respiratory research》2015,16(1)
Background
Although the endurance shuttle walk test (ESWT) has proven to be responsive to change in exercise capacity after pulmonary rehabilitation (PR) for COPD, the minimally important difference (MID) has not yet been established. We aimed to establish the MID of the ESWT in patients with severe COPD and chronic hypercapnic respiratory failure following PR.Methods
Data were derived from a randomized controlled trial, investigating the value of noninvasive positive pressure ventilation added to PR. Fifty-five patients with stable COPD, GOLD stage IV, with chronic respiratory failure were included (mean (SD) FEV1 31.1 (12.0) % pred, age 62 (9) y). MID estimates of the ESWT in seconds, percentage and meters change were calculated with anchor based and distribution based methods. Six minute walking distance (6MWD), peak work rate on bicycle ergometry (Wpeak) and Chronic Respiratory Questionnaire (CRQ) were used as anchors and Cohen’s effect size was used as distribution based method.Results
The estimated MID of the ESWT with the different anchors ranged from 186–199 s, 76–82% and 154–164 m. Using the distribution based method the MID was 144 s, 61% and 137 m.Conclusions
Estimates of the MID for the ESWT after PR showed only small differences using different anchors in patients with COPD and chronic respiratory failure. Therefore we recommend using a range of 186–199 s, 76–82% or 154–164 m as MID of the ESWT in COPD patients with chronic respiratory failure. Further research in larger populations should elucidate whether this cut-off value is also valid in other COPD populations and with other interventions.Trial registration
ClinicalTrials.Gov (ID ). NCT00135538Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0182-x) contains supplementary material, which is available to authorized users. 相似文献127.
James GD Prendergast Harry Campbell Nick Gilbert Malcolm G Dunlop Wendy A Bickmore Colin AM Semple 《BMC evolutionary biology》2007,7(1):72
Background
Evolutionary rates are not constant across the human genome but genes in close proximity have been shown to experience similar levels of divergence and selection. The higher-order organisation of chromosomes has often been invoked to explain such phenomena but previously there has been insufficient data on chromosome structure to investigate this rigorously. Using the results of a recent genome-wide analysis of open and closed human chromatin structures we have investigated the global association between divergence, selection and chromatin structure for the first time. 相似文献128.
Guillaume Laval Nathalie Iannuccelli Christian Legault Denis Milan Martien AM Groenen Elisabetta Giuffra Leif Andersson Peter H Nissen Claus B J?rgensen Petra Beeckmann Hermann Geldermann Jean-Louis Foulley Claude Chevalet Louis Ollivier 《遗传、选种与进化》2000,32(2):187-203
A set of eleven pig breeds originating from six European countries, and including a small sample of wild pigs, was chosen for this study of genetic diversity. Diversity was evaluated on the basis of 18 microsatellite markers typed over a total of 483 DNA samples collected. Average breed heterozygosity varied from 0.35 to 0.60. Genotypic frequencies generally agreed with Hardy-Weinberg expectations, apart from the German Landrace and Schwäbisch-Hällisches breeds, which showed significantly reduced heterozygosity. Breed differentiation was significant as shown by the high among-breed fixation index (overall FST = 0.27), and confirmed by the clustering based on the genetic distances between individuals, which grouped essentially all individuals in 11 clusters corresponding to the 11 breeds. The genetic distances between breeds were first used to construct phylogenetic trees. The trees indicated that a genetic drift model might explain the divergence of the two German breeds, but no reliable phylogeny could be inferred among the remaining breeds. The same distances were also used to measure the global diversity of the set of breeds considered, and to evaluate the marginal loss of diversity attached to each breed. In that respect, the French Basque breed appeared to be the most "unique" in the set considered. This study, which remains to be extended to a larger set of European breeds, indicates that using genetic distances between breeds of farm animals in a classical taxonomic approach may not give clear resolution, but points to their usefulness in a prospective evaluation of diversity. 相似文献
129.
Szklarczyk R Wanschers BF Cuypers TD Esseling JJ Riemersma M van den Brand MA Gloerich J Lasonder E van den Heuvel LP Nijtmans LG Huynen MA 《Genome biology》2012,13(2):R12-14
Background
Orthology is a central tenet of comparative genomics and ortholog identification is instrumental to protein function prediction. Major advances have been made to determine orthology relations among a set of homologous proteins. However, they depend on the comparison of individual sequences and do not take into account divergent orthologs.Results
We have developed an iterative orthology prediction method, Ortho-Profile, that uses reciprocal best hits at the level of sequence profiles to infer orthology. It increases ortholog detection by 20% compared to sequence-to-sequence comparisons. Ortho-Profile predicts 598 human orthologs of mitochondrial proteins from Saccharomyces cerevisiae and Schizosaccharomyces pombe with 94% accuracy. Of these, 181 were not known to localize to mitochondria in mammals. Among the predictions of the Ortho-Profile method are 11 human cytochrome c oxidase (COX) assembly proteins that are implicated in mitochondrial function and disease. Their co-expression patterns, experimentally verified subcellular localization, and co-purification with human COX-associated proteins support these predictions. For the human gene C12orf62, the ortholog of S. cerevisiae COX14, we specifically confirm its role in negative regulation of the translation of cytochrome c oxidase.Conclusions
Divergent homologs can often only be detected by comparing sequence profiles and profile-based hidden Markov models. The Ortho-Profile method takes advantage of these techniques in the quest for orthologs. 相似文献130.
SE?Aleshin AV?Timofeev MV?Khoretonenko LG?Zakharova GV?Pashvykina JR?Stephenson AM?Shneider AD?AltsteinEmail author 《BMC microbiology》2005,5(1):45