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31.
Darwin KH Ehrt S Gutierrez-Ramos JC Weich N Nathan CF 《Science (New York, N.Y.)》2003,302(5652):1963-1966
The production of nitric oxide and other reactive nitrogen intermediates (RNI) by macrophages helps to control infection by Mycobacterium tuberculosis (Mtb). However, the protection is imperfect and infection persists. To identify genes that Mtb requires to resist RNI, we screened 10,100 Mtb transposon mutants for hypersusceptibility to acidified nitrite. We found 12 mutants with insertions in seven genes representing six pathways, including the repair of DNA (uvrB) and the synthesis of a flavin cofactor (fbiC). Five mutants had insertions in proteasome-associated genes. An Mtb mutant deficient in a presumptive proteasomal adenosine triphosphatase was attenuated in mice, and exposure to proteasomal protease inhibitors markedly sensitized wild-type Mtb to RNI. Thus, the mycobacterial proteasome serves as a defense against oxidative or nitrosative stress. 相似文献
32.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
33.
Custódio L Escapa AL Fernandes E Fajardo A Aligué R Alberício F Neng N Nogueira JM Romano A 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(1):78-84
This work aimed to evaluate the phytochemical content and to determine the antioxidant and cytotoxic activities of methanol
extracts of the carob tree (Ceratonia siliqua L.) germ flour. The extracts were rich in phenolic compounds, had considerable antioxidant activity, and reduced the viability
of cervical (HeLa) cancer cells. The chemical content and the biological activities of the extracts were significantly affected
by gender and cultivar. Female cultivar Galhosa had the highest levels of phenolic compounds, and the highest antioxidant
activity. Extracts from the hermaphrodite trees and from the female cultivars Galhosa and Costela/Canela exhibited the highest
cytotoxic activity. The most abundant compound was theophylline. The phenolic content was correlated to both antioxidant and
cytotoxic activities. Our findings provide new knowledge about the health implications of consuming food supplemented with
carob germ flour. 相似文献
34.
35.
Intraguild predation of Geocoris punctipes on Eretmocerus eremicus and its influence on the control of the whitefly Trialeurodes vaporariorum 下载免费PDF全文
36.
Lina Maria Correa E Ricardo D. Moreno José Luis Riveros 《Anatomia, histologia, embryologia》2023,52(2):336-340
This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries. 相似文献
37.
Ana M. Guti��rrez Jos�� J. Cer��n Blas A. Marsilla Mar��a D. Parra Silvia Martinez-Subiela 《Canadian journal of veterinary research》2012,76(2):136-142
A new method was developed to simultaneously measure 2 acute-phase proteins (APPs) by time-resolved immunofluorometry. The assay, based on double-label quantification of haptoglobin (Hp) and C-reactive protein (CRP) in meat juice samples from pigs, was constructed by use of a combination of europium and samarium chelate lanthanides as labels. Meat juice samples from 154 pigs were used for analytic and clinical validation of the assay through determination of precision, accuracy, limit of detection, and quantification. The analytic performance of the assay was satisfactory, with good intra-assay and interassay precision and accuracy. The levels of Hp and CRP were increased in the meat juice samples of diseased animals compared with healthy ones. According to the results, higher sensitivity could be achieved if the cut-off values of both proteins were taken into account for clinical relevance rather than used individually. Since the dual assay saved both time and sample, it could be used as a rapid and sensitive screening test in porcine production. 相似文献
38.
Adherence of Actinobacillus pleuropneumoniae to primary cultures of porcine lung epithelial cells 总被引:2,自引:0,他引:2
Boekema BK Stockhofe-Zurwieden N Smith HE Kamp EM van Putten JP Verheijden JH 《Veterinary microbiology》2003,93(2):133-144
To study adherence of Actinobacillus pleuropneumoniae to porcine lower respiratory epithelium, a cell culture model was developed using primary cultures of porcine lung epithelial cells (LEC). Adherence assays were performed and results were compared with data obtained with swine kidney cells (SK6). A. pleuropneumoniae efficiently adhered to LEC with up to 62 bacteria per cell after 2h of incubation. Reference strain of serotype 3 (R3) adhered better to LEC than reference strains of serotypes 1 (R1), 7 (R7) and 8 (R8). Overall the adherence to LEC was more rapid and up to 30-fold more efficient than adherence to SK6 cells. In search for the mechanism involved in the adherence event, we tested the effect of LPS which has previously been demonstrated to cause adherence of the pathogen to upper respiratory epithelium. Adherence assays with LPS transposon mutants demonstrated unaltered (mutant with modification in core/lipid A moiety) or even three-fold more adherence (mutants lacking O antigen) compared to the parent micro-organisms. Purified LPS of strains R1, R3, R7 and R8 did not inhibit adherence of R8 to LEC either, suggesting that LPS and particularly the O-antigen are not essential for adherence of A. pleuropneumoniae to LEC. The efficient, LPS-independent adherence of A. pleuropneumoniae to LEC cells indicates that A. pleuropneumoniae may carry different, cell type-specific adhesins and that primary cultures of lower respiratory epithelium are valuable infection models in studying A. pleuropneumoniae pathogenesis. 相似文献
39.