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排序方式: 共有692条查询结果,搜索用时 62 毫秒
91.
92.
S Papa N E Lofrumento D Kanduc G Paradies E Quagliariello 《European journal of biochemistry》1971,22(1):134-143
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Siti Maziras Makhtar Azlan Husin Abdul Aziz Baba Ravindran Ankathil 《Journal of genetics》2018,97(4):835-842
Imatinib mesylate (IM), a well-established gold standard drug in the treatment of chronic myeloid leukaemia (CML), is a synthetic tyrosine kinase inhibitor. Despite excellent efficacy, a significant number of patients on IM therapy develop resistance to IM. Currently, great focus has been laid on the effect of interindividual pharmacogenetic variability on IM treatment responses. IM uptake is mediated by the hOCT1 protein encoded by the solute carrier 22 gene (SLC22A1). The current study investigated the impact of few single-nucleotide polymorphisms (SNPs) of SLC22A1 on mediating resistance and/or good response to IM among 278 Malaysian CML patients (146 IM-resistant group and 132 IM good response group) undergoing IM therapy on 400 mg daily. Our results showed that the allelic frequencies of heterozygous (CG) and homozygous variant (GG) genotypes of SLC22A1 C480G were significantly higher in the IM-resistant group compared with the IM good response group (41.8% versus 30.3% and 10.9% versus 4.5% with P values of 0.047 and 0.048, respectively). On evaluating the association of genotypes with risk of IM resistance development, heterozygous (CG) and homozygous (GG) variant genotypes showed significantly higher risk for developing resistance to IM treatment with odds ratio (OR): 1.901 (95% confidence interval (CI): 1.142–3.163, \(P=0.013\)) and 3.324 (95% CI: 1.235–8.947, \(P=0.017\)), respectively. Two SNPs and two insertions/deletions were detected in exon 7 of SLC22A1. For exon 7, 1222AA carriers together with the presence of both the 8-bp insertion and 3-bp deletion, and M420del alleles showed higher possibility of developing resistance towards IM treatment. Our results warrant the need of genotyping this SNP in terms of modulating IM treatment in CML patients. 相似文献
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Corcelli A Lobasso S Palese LL Saponetti MS Papa S 《Biochemical and biophysical research communications》2007,354(3):795-801
Membranes having an a high content of cardiolipin were isolated from an extremely halophilic archaeon Halorubrum sp. Absorbance difference spectra of detergent-solubilized plasma membranes reduced by dithionite suggested the presence of b-type cytochromes. Non-denaturing gel electrophoresis revealed only one fraction having TMPD-oxidase activity in which cardiolipin was the major lipid component. The electroeluted fraction showed a cytochrome c oxidase activity characterized by the reduced minus oxidized difference spectra as a terminal heme-copper oxidase. The cytochrome c oxidase activity of the archaeal cardiolipin-rich membranes was inhibited by the cardiolipin-specific fluorescent marker 10-N-nonyl acridine orange (NAO) in a dose-dependent manner. The results indicate that an archaeal analogue of cardiolipin is tightly associated to archaeal terminal oxidases and is required for its optimal functioning. 相似文献
97.
Isolation and Characterization of Alfalfa-Nodulating Rhizobia Present in Acidic Soils of Central Argentina and Uruguay 总被引:12,自引:1,他引:11
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María F. del Papa Laura J. Balagu Susana Castro Sowinski Caren Wegener Eduardo Segundo Francisco Martínez Abarca Nicols Toro Karsten Niehaus Alfred Pühler O. Mario Aguilar Gloria Martínez-Drets Antonio Lagares 《Applied microbiology》1999,65(4):1420-1427
We describe the isolation and characterization of alfalfa-nodulating rhizobia from acid soils of different locations in Central Argentina and Uruguay. A collection of 465 isolates was assembled, and the rhizobia were characterized for acid tolerance. Growth tests revealed the existence of 15 acid-tolerant (AT) isolates which were able to grow at pH 5.0 and formed nodules in alfalfa with a low rate of nitrogen fixation. Analysis of those isolates, including partial sequencing of the genes encoding 16S rRNA and genomic PCR-fingerprinting with MBOREP1 and BOXC1 primers, demonstrated that the new isolates share a genetic background closely related to that of the previously reported Rhizobium sp. Or191 recovered from an acid soil in Oregon (B. D. Eardly, J. P. Young, and R. K. Selander, Appl. Environ. Microbiol. 58:1809–1815, 1992). Growth curves, melanin production, temperature tolerance, and megaplasmid profiles of the AT isolates were all coincident with these characteristics in strain Or191. In addition to the ability of all of these strains to nodulate alfalfa (Medicago sativa) inefficiently, the AT isolates also nodulated the common bean and Leucaena leucocephala, showing an extended host range for nodulation of legumes. In alfalfa, the time course of nodule formation by the AT isolate LPU 83 showed a continued nodulation restricted to the emerging secondary roots, which was probably related to the low rate of nitrogen fixation by the largely ineffective nodules. Results demonstrate the complexity of the rhizobial populations present in the acidic soils represented by a main group of N2-fixing rhizobia and a second group of ineffective and less-predominant isolates related to the AT strain Or191. 相似文献
98.
James G. Ogilvie Steven Van Belleghem Ryan Range Riccardo Papa Owen W. McMillan Mathieu Chouteau Brian A. Counterman 《Ecology and evolution》2021,11(24):18319
The evolution of mimicry in similarly defended prey is well described by the Müllerian mimicry theory, which predicts the convergence of warning patterns in order to gain the most protection from predators. However, despite this prediction, we can find great diversity of color patterns among Müllerian mimics such as Heliconius butterflies in the neotropics. Furthermore, some species have evolved the ability to maintain multiple distinct warning patterns in single populations, a phenomenon known as polymorphic mimicry. The adaptive benefit of these polymorphisms is questionable since variation from the most common warning patterns is expected to be disadvantageous as novel signals are punished by predators naive to them. In this study, we use artificial butterfly models throughout Central and South America to characterize the selective pressures maintaining polymorphic mimicry in Heliconius doris. Our results highlight the complexity of positive frequency‐dependent selection, the principal selective pressure driving convergence among Müllerian mimics, and its impacts on interspecific variation of mimetic warning coloration. We further show how this selection regime can both limit and facilitate the diversification of mimetic traits. 相似文献
99.
Marco Artini Paola Cicatiello Annarita Ricciardelli Rosanna Papa Laura Selan Principia Dardano 《Biofouling》2017,33(7):601-611
Staphylococcus epidermidis is a significant nosocomial pathogen in predisposed hosts because of its capability of forming a biofilm on indwelling medical devices. The initial stage of biofilm formation has a key role in S. epidermidis abiotic surface colonization. Recently, many strategies have been developed to create new anti-biofilm surfaces able to control bacterial adhesion mechanisms. In this work, the self-assembled amphiphilic layers formed by two fungal hydrophobins (Vmh2 and Pac3) have proven to be able to reduce the biofilm formed by different strains of S. epidermidis on polystyrene surfaces. The reduction in the biofilm thickness on the coated surfaces and the preservation of cell vitality have been demonstrated through confocal laser scanning microscope analysis. Moreover, the anti-biofilm efficiency of the self-assembled layers on different medically relevant materials has also been demonstrated using a CDC biofilm reactor. 相似文献
100.
Walter Omar Draghi María Florencia Del Papa Aiko Barsch Francisco J. Albicoro Mauricio J. Lozano Alfred Pühler Karsten Niehaus Antonio Lagares 《Metabolomics : Official journal of the Metabolomic Society》2017,13(6):71