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911.
Mohankumar Kumaravel Francis Arul Prakash Pajaniradje Sankar Rajagopalan Rukkumani 《Molecular biology reports》2021,48(8):6065-6074
Molecular Biology Reports - Laryngeal carcinoma, the most common among head and neck squamous cell carcinoma (HNSCC), induces 1% of all cancer deaths. Curcumin the active constituent of turmeric,... 相似文献
912.
913.
Noël Grégoire Serteyn Laurent Sare Abdoul Razack Massart Sébastien Delvigne Frank Francis Frédéric 《International microbiology》2023,26(2):397-409
International Microbiology - The current plastic pollution throughout the world is a rising concern that demands the optimization of biodegradation processes. One avenue for this is to identify... 相似文献
914.
Bruna Jardim Pereira Lima Gabriel Rodrigues Leal de Oliveira Thainá Cavalleri Sousa Ariana Musa de Aquino Karianne Delalibera Hinokuma Maria Luiza Silva Ricardo Wellerson Rodrigo Scarano Anthony César de Souza Castilho Francis Lopes Pacagnelli Francisco Eduardo Martinez Leonardo de Oliveira Mendes 《Animal Reproduction》2023,20(3)
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916.
Travis ER Gaze WH Pontiroli A Sweeney FP Porter D Mason S Keeling MJ Jones RM Sawyer J Aranaz A Rizaldos EC Cork J Delahay RJ Wilson GJ Hewinson RG Courtenay O Wellington EM 《PloS one》2011,6(11):e27369
Advances in the diagnosis of Mycobacterium bovis infection in wildlife hosts may benefit the development of sustainable approaches to the management of bovine tuberculosis in cattle. In the present study, three laboratories from two different countries participated in a validation trial to evaluate the reliability and reproducibility of a real time PCR assay in the detection and quantification of M. bovis from environmental samples. The sample panels consisted of negative badger faeces spiked with a dilution series of M. bovis BCG Pasteur and of field samples of faeces from badgers of unknown infection status taken from badger latrines in areas with high and low incidence of bovine TB (bTB) in cattle. Samples were tested with a previously optimised methodology. The experimental design involved rigorous testing which highlighted a number of potential pitfalls in the analysis of environmental samples using real time PCR. Despite minor variation between operators and laboratories, the validation study demonstrated good concordance between the three laboratories: on the spiked panels, the test showed high levels of agreement in terms of positive/negative detection, with high specificity (100%) and high sensitivity (97%) at levels of 10(5) cells g(-1) and above. Quantitative analysis of the data revealed low variability in recovery of BCG cells between laboratories and operators. On the field samples, the test showed high reproducibility both in terms of positive/negative detection and in the number of cells detected, despite low numbers of samples identified as positive by any laboratory. Use of a parallel PCR inhibition control assay revealed negligible PCR-interfering chemicals co-extracted with the DNA. This is the first example of a multi-laboratory validation of a real time PCR assay for the detection of mycobacteria in environmental samples. Field studies are now required to determine how best to apply the assay for population-level bTB surveillance in wildlife. 相似文献
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918.
Drought‐stress and plant resistance affect herbivore performance and proteome: the case of the green peach aphid Myzus persicae (Hemiptera: Aphididae) 下载免费PDF全文
Jaime A. Verdugo Marie‐Helene Sauge Jean‐Philippe Lacroze Frederic Francis Claudio C. Ramirez 《Physiological Entomology》2015,40(4):265-276
Little is known about the simultaneous effects of drought stress and plant resistance on herbivorous insects. By subjecting the green peach aphid Myzus persicae Sulzer to well‐watered and drought‐stressed plants of both susceptible and resistant peach (Prunus persica), the effects of both stressors on aphid performance and proteomics are tested. Overall, the influence of the water treatment on aphid performance is less pronounced than the effect of host plant genetic resistance. On the susceptible cultivar, aphid survival, host acceptance and ability to colonize the plant do not depend on water treatment. On the resistant cultivar, aphid survival and ability to colonize are higher on drought‐stressed than on well‐watered plants. A study examining the pattern of protein expression aiming to explain the variation in aphid performance finds higher protein expression in aphids on the drought‐stressed susceptible cultivars compared with the well‐watered ones. In the susceptible cultivar, the regulated proteins are related to energy metabolism and exoskeleton functionality, whereas, in the resistant cultivar, the proteins are involved with the cytoskeleton. Comparison of the protein expression ratios for resistant versus susceptible plants reveals that four proteins are down‐regulated in well‐watered plants and 15 proteins are down‐regulated in drought‐stressed plants. Drought stress applied to the susceptible cultivar induces the regulation of proteins in M. persicae that enable physiological adaptation to maintain an almost unaltered aphid performance. By contrast, for aphids on the resistant cultivar subjected to drought stress, the down‐regulation of proteins responds to an induced host susceptibility effect. 相似文献
919.
Attila Egri-Nagy Volker Gebhardt Mark M. Tanaka Andrew R. Francis 《Journal of mathematical biology》2014,69(1):243-265
The variation in genome arrangements among bacterial taxa is largely due to the process of inversion. Recent studies indicate that not all inversions are equally probable, suggesting, for instance, that shorter inversions are more frequent than longer, and those that move the terminus of replication are less probable than those that do not. Current methods for establishing the inversion distance between two bacterial genomes are unable to incorporate such information. In this paper we suggest a group-theoretic framework that in principle can take these constraints into account. In particular, we show that by lifting the problem from circular permutations to the affine symmetric group, the inversion distance can be found in polynomial time for a model in which inversions are restricted to acting on two regions. This requires the proof of new results in group theory, and suggests a vein of new combinatorial problems concerning permutation groups on which group theorists will be needed to collaborate with biologists. We apply the new method to inferring distances and phylogenies for published Yersinia pestis data. 相似文献
920.
Dziva F Mahajan A Cameron P Currie C McKendrick IJ Wallis TS Smith DG Stevens MP 《FEMS microbiology letters》2007,271(2):258-264
Enterohaemorrhagic Escherichia coli (EHEC) comprise a group of zoonotic diarrhoeal pathogens of worldwide importance. Cattle are a key reservoir; however the molecular mechanisms that promote persistent colonization of the bovine intestines by EHEC are ill-defined. The large plasmid of EHEC O157:H7 encodes several putative virulence factors. Here, it is reported that the pO157-encoded Type V-secreted serine protease EspP influences the intestinal colonization of calves. To dissect the basis of attenuation, a bovine primary rectal epithelial cell line was developed. Adherence of E. coli O157:H7 to such cells was significantly impaired by espP mutation but restored upon addition of highly purified exogenous EspP. Data of this study add to the growing body of evidence that cytotoxins facilitate intestinal colonization by EHEC. 相似文献