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81.
The endothelium is a dynamic, heterogeneous, disseminated organ that possesses vital secretory, synthetic, metabolic and immunological functions. Endothelial dysfunction has been implicated as a key factor in the development of organ-specific vascular diseases. This minireview gives a brief overview on EC (endothelial cell) biomarkers in arterial and venous endothelium and critically discusses the different sources of ECs that are most frequently applied in in vitro assays and research. The relevance of organ- and disease-specific endothelial cell cultures for studying cellular responses as a basis for improving therapeutic interventions is highlighted with particular emphasis on endothelial dysfunction in transplant-associated coronary artery disease, in atherosclerotic lesions and in response to diabetes mellitus. 相似文献
82.
Flavio M. Lopes Karla A. Batista Gustavo L. A. Batista Sydnei Mitidieri Luiz Artur M. Bataus Kátia F. Fernandes 《World journal of microbiology & biotechnology》2010,26(7):1155-1161
Three bacterial strains have been isolated from soil in which soybean had been continuously cropped and treated with Opera®, a fungicide containing epoxyconazole and pyraclostrobin. The three strains (1,805, 2,801 and 3,803), obtained from soil at 80–100 cm depth, were selected on medium containing 0.03% Opera®. Morphological examination revealed that the strains were Gram-negative, and two of them (1,805 and 2,801) exhibited polymorphism. The growth profiles demonstrated that 1,805 and 3,803 were more efficient growing in the presence of Opera® than 2,801. Maximum growth was reached between 24 and 48 h, however, 2,801 was not able to survive after this period. The total protein content produced by 1,805, 2,801 and 3,803 in liquid selective medium containing Opera® were 111.0 ± 0.02, 80.0 ± 0.05 and 130.5 ± 0.07 μg/ml, respectively. According to its biochemical and molecular features, strain 1,805 was identified as Klebsiella sp. On the basis of the characteristics presented (facultative anaerobic nature, polymorphic character and capacity of growing in the presence of Opera®) strain 1,805 seems to be able to degrade the epoxyconazole and pyraclostrobin. 相似文献
83.
Poornima Parameswaran Ella Sklan Courtney Wilkins Trever Burgon Melanie A. Samuel Rui Lu K. Mark Ansel Vigo Heissmeyer Shirit Einav William Jackson Tammy Doukas Suman Paranjape Charlotta Polacek Flavia Barreto dos Santos Roxana Jalili Farbod Babrzadeh Baback Gharizadeh Dirk Grimm Mark Kay Satoshi Koike Peter Sarnow Mostafa Ronaghi Shou-Wei Ding Eva Harris Marie Chow Michael S. Diamond Karla Kirkegaard Jeffrey S. Glenn Andrew Z. Fire 《PLoS pathogens》2010,6(2)
We have used multiplexed high-throughput sequencing to characterize changes in small RNA populations that occur during viral infection in animal cells. Small RNA-based mechanisms such as RNA interference (RNAi) have been shown in plant and invertebrate systems to play a key role in host responses to viral infection. Although homologs of the key RNAi effector pathways are present in mammalian cells, and can launch an RNAi-mediated degradation of experimentally targeted mRNAs, any role for such responses in mammalian host-virus interactions remains to be characterized. Six different viruses were examined in 41 experimentally susceptible and resistant host systems. We identified virus-derived small RNAs (vsRNAs) from all six viruses, with total abundance varying from “vanishingly rare” (less than 0.1% of cellular small RNA) to highly abundant (comparable to abundant micro-RNAs “miRNAs”). In addition to the appearance of vsRNAs during infection, we saw a number of specific changes in host miRNA profiles. For several infection models investigated in more detail, the RNAi and Interferon pathways modulated the abundance of vsRNAs. We also found evidence for populations of vsRNAs that exist as duplexed siRNAs with zero to three nucleotide 3′ overhangs. Using populations of cells carrying a Hepatitis C replicon, we observed strand-selective loading of siRNAs onto Argonaute complexes. These experiments define vsRNAs as one possible component of the interplay between animal viruses and their hosts. 相似文献
84.
85.
Alcides AP Brazier JS Pinto LJ Balassiano IT Boente RF de Paula GR Ferreira EO Avelar KE Miranda KR Ferreira MC Domingues RM 《Antonie van Leeuwenhoek》2007,92(1):53-59
A total of 35 Brazilian isolates of Clostridium difficile from faecal stools and four isolates from hospital environments were analyzed by PCR ribotyping. A whole cell protein profile
(as an alternative for serogrouping), in vitro toxin production and susceptibility to vancomycin, metronidazole and clindamycin
were also investigated. All strains were typeable by both phenotypic and genotypic methods, and a total of 13 different PCR
ribotypes were identified, of which seven (132, 133, 134, 135, 136, 142 and 143) were considered new types and accounted for
78.5% of all samples evaluated (including hospital environments). A non-toxigenic C. difficile PCR ribotype 133 was detected in all children groups examined (inpatients, outpatients and healthy children), whilst toxigenic
PCR ribotypes 015, 131, 134 and 135 were associated mostly with symptomatic children. Serogroups G and D were disseminated
both in patients from the community and from the pediatric hospital, with group G prevalent among outpatient children. All
strains were susceptible to vancomycin and metronidazole but high levels of resistance to clindamycin were found, especially
among serogroups G and D. Co-existence of different ribotypes and serogroups in the same individual was observed. The new
seven ribotypes found in this investigation may represent strains characteristic of this region of Brazil. 相似文献
86.
Functional and crystal structure analysis of active site adaptations of a potent anti-angiogenic human tRNA synthetase 总被引:1,自引:0,他引:1
Yang XL Guo M Kapoor M Ewalt KL Otero FJ Skene RJ McRee DE Schimmel P 《Structure (London, England : 1993)》2007,15(7):793-805
Higher eukaryote tRNA synthetases have expanded functions that come from enlarged, more differentiated structures that were adapted to fit aminoacylation function. How those adaptations affect catalytic mechanisms is not known. Presented here is the structure of a catalytically active natural splice variant of human tryptophanyl-tRNA synthetase (TrpRS) that is a potent angiostatic factor. This and related structures suggest that a eukaryote-specific N-terminal extension of the core enzyme changed substrate recognition by forming an active site cap. At the junction of the extension and core catalytic unit, an arginine is recruited to replace a missing landmark lysine almost 200 residues away. Mutagenesis, rapid kinetic, and substrate binding studies support the functional significance of the cap and arginine recruitment. Thus, the enzyme function of human TrpRS has switched more to the N terminus of the sequence. This switch has the effect of creating selective pressure to retain the N-terminal extension for functional expansion. 相似文献
87.
Peña-Rico Miguel A. Bravo-D Humberto R. Roldan-Sabino Crisanto Castro-Cerritos Karla V. Huerta-Heredia Ariana Navarro-Mtz A. Karin 《Antonie van Leeuwenhoek》2022,115(1):89-102
Antonie van Leeuwenhoek - Bacillus thuringiensis is the major bioinsecticide worldwide produced due to the Cry protein activity. Several studies have been done to improve the... 相似文献
88.
Hydrobiologia - Theory predicts that species can only coexist if they are sufficiently different in their resource and/or microhabitat utilization; if their needs are too similar, the stronger... 相似文献
89.
Marc Solà-Ginés Juan José González-López Karla Cameron-Veas Nuria Piedra-Carrasco Marta Cerdà-Cuéllar Lourdes Migura-Garcia 《Applied and environmental microbiology》2015,81(11):3604-3611
Flies may act as potential vectors for the spread of resistant bacteria to different environments. This study was intended to evaluate the presence of Escherichia coli strains resistant to cephalosporins in flies captured in the areas surrounding five broiler farms. Phenotypic and molecular characterization of the resistant population was performed by different methods: MIC determination, pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and phylotyping. The presence of extended-spectrum beta-lactamase (ESBL) genes, their plasmid location, and the mobile genetic elements involved in their mobilization were studied. Additionally, the presence of 35 genes associated with virulence was evaluated. Out of 682 flies captured, 42 yielded ESBL-producing E. coli. Of these isolates, 23 contained blaCTX-M-1, 18 contained blaCTX-M-14, and 1 contained blaCTX-M-9. ESBL genes were associated mainly with the presence of the IncI1 and IncFIB replicons. Additionally, all the strains were multiresistant, and five of them also harbored qnrS. Identical PFGE profiles were found for E. coli isolates obtained from flies at different sampling times, indicating a persistence of the same clones in the farm environment over months. According to their virulence genes, 81% of the isolates were considered avian-pathogenic E. coli (APEC) and 29% were considered extraintestinal pathogenic E. coli (ExPEC). The entrance of flies into broiler houses constitutes a considerable risk for colonization of broilers with multidrug-resistant E. coli. ESBLs in flies reflect the contamination status of the farm environment. Additionally, this study demonstrates the potential contribution of flies to the dissemination of virulence and resistance genes into different ecological niches. 相似文献
90.
Karla?V.?Figueiredo Marciel?T.?Oliveira Emília?C.?P.?Arruda Bárbara?C.?F.?Silva Mauro?G.?SantosEmail author 《Acta Physiologiae Plantarum》2015,37(6):108
Jatropha curcas and Jatropha mollissima plants were evaluated under conditions of high (HSM) and low (LSM) soil moisture in a semi-arid environment, as changes in the content and concentration of epicuticular wax and the leaf metabolism which could have a relationship with drought tolerance. Besides epicuticular wax, gas exchange, antioxidant system and biochemical parameters of the photosynthetic metabolism were measured. The epicuticular wax content increased only in J. mollissima leaves 95 % under LSM, when compared with HSM conditions. Therefore, J. curcas invested less in the production of long-chain n-alkanes than did J. mollissima under LSM conditions. J. mollissima plants showed the highest CO2 assimilation rate during the HSM period compared to J. curcas. Both species showed high stability in some leaf biochemistry products, highlighting the highest sugar content, free amino acids, total soluble protein, and photosynthetic pigments in the leaves of J. mollissima plants under both of the soil moisture conditions. Moreover, the stability and performance of the different parameters, such as morphologic variables, seem to allow J. mollissima plants to tolerate semi-arid conditions. 相似文献