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71.
Gonzalez A Lenzi HL Motta EM Caputo L Sahaza JH Cock AM Ruiz AC Restrepo A Cano LE 《Microbes and infection / Institut Pasteur》2005,7(4):666-673
In infected tissues, leukocyte recruitment is mediated by interactions between adhesion molecules, expressed on activated vascular endothelial cells, and ligands present on circulating cells. We evaluated the inflammatory response and the expression of cellular adhesion molecules (ICAM-1, VCAM-1, CD18, LFA-1 and Mac-1) in lungs of BALB/c mice infected with Paracoccidioides brasiliensis conidia. When compared with uninfected animals, infected mice had a significant increase in the inflammatory response during the first 4 days, peaking 2-3 days post-challenge, 40.3% vs. 0.0% and 41.8% vs. 0.7%, respectively. This inflammatory infiltrate was composed mainly of neutrophils and macrophages with a few eosinophils and lymphocytes. An increase in the intensity of immunofluorescence (IF) for ICAM-1 was also observed during days 1-4. ICAM-1 was present in bronchiolar epithelium, type II pneumocytes, and macrophages, as well as on vascular endothelium. The control animals presented ICAM-1 constitutively. In infected mice, VCAM-1 was only observed on vascular endothelium during the first 2 days, with some macrophages expressing this molecule throughout the study periods. CD18 and Mac-1 but not LFA-1 were expressed with a high intensity on neutrophils and macrophages present in the inflammatory infiltrate. In addition, we observed a significant decrease in Colony forming units (CFUs) after the first 2 days post-challenge. These findings suggest that during these early stages, up-regulation of ICAM-1, VCAM-1, CD18 and Mac-1 expression occurs, participating in the inflammatory process and as such, in the pathogenesis of paracoccidioidomycosis (PCM). 相似文献
72.
Flávio Ricardo Guilherme Carlos Alexandre Molena-Fernandes Luzia Jaeger Hintze Maria Teresa Martins Fávero Roberto Kenji Nakamura Cuman Wilson Rinaldi 《PloS one》2014,9(11)
ObjectiveTo identify the prevalence of hypertriglyceridemic waist (HTW) phenotype and its association with metabolic abnormalities in schoolchildren.MethodsA cross-sectional study, with a sample of 241 students aged 10 to 14 years from public schools (4 schools) and private (2 schools) from Paranavai town, in Parana State, Brazil. Anthropometric variables (weight, height, waist circumference) and levels of triglycerides, total cholesterol, HDL-C, non-HDL and LDL-C were analyzed. In statistical tests of Pearson partial correlation and multivariate logistic regression, considering p<0,05.ResultsThe prevalence of HTW was 20,7% among schoolchildren, 14,1% in males and 6,6% among females with higher proportions aged 10–12 years old. Multivariate analysis indicated that the students who attended private schools were nearly three times more likely (95% CI: 1,2–5,6), to be diagnosed with HTW compared with those who attended public schools (p = 0,006), and LDL-C was the only metabolic variable positively associated with the outcome (p = 0,001), where the students categorized with elevated serum levels had odds 4,2 times (95% CI: 1,6–10,9) having the HTW compared to students in appropriate levels.ConclusionThis study showed higher prevalence of hypertriglyceridemic waist phenotype in students when compared to prospective studies in Brazil and worldwide. It also showed that the only metabolic alteration associated with HTW phenotype was LDL-C (low density lipoprotein). 相似文献
73.
da Silva Matheus Nunes Granzotti Rafaela Vendrametto de Carvalho Priscilla Rodrigues Luzia Cleide Bini Luis Mauricio 《Limnology》2021,22(1):121-127
Limnology - Spatial synchrony occurs when local populations exhibit correlated dynamics over time. Recent studies, both experimental and observational, have indicated that the magnitude of spatial... 相似文献
74.
Sarmento RA Lemos F Dias CR Kikuchi WT Rodrigues JC Pallini A Sabelis MW Janssen A 《PloS one》2011,6(8):e23757
Herbivores may interact with each other through resource competition, but also through their impact on plant defence. We recently found that the spider mite Tetranychus evansi down-regulates plant defences in tomato plants, resulting in higher rates of oviposition and population growth on previously attacked than on unattacked leaves. The danger of such down-regulation is that attacked plants could become a more profitable resource for heterospecific competitors, such as the two-spotted spider mite Tetranychus urticae. Indeed, T. urticae had an almost 2-fold higher rate of oviposition on leaf discs on which T. evansi had fed previously. In contrast, induction of direct plant defences by T. urticae resulted in decreased oviposition by T. evansi. Hence, both herbivores affect each other through induced plant responses. However, when populations of T. evansi and T. urticae competed on the same plants, populations of the latter invariably went extinct, whereas T. evansi was not significantly affected by the presence of its competitor. This suggests that T. evansi can somehow prevent its competitor from benefiting from the down-regulated plant defence, perhaps by covering it with a profuse web. Indeed, we found that T. urticae had difficulties reaching the leaf surface to feed when the leaf was covered with web produced by T. evansi. Furthermore, T. evansi produced more web when exposed to damage or other cues associated with T. urticae. We suggest that the silken web produced by T. evansi serves to prevent competitors from profiting from down-regulated plant defences. 相似文献
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78.
The presence of qacA/B gene in Brazilian methicillin-resistant Staphylococcus aureus 总被引:3,自引:0,他引:3
Miyazaki NH Abreu AO Marin VA Rezende CA Moraes MT Villas Bôas MH 《Memórias do Instituto Oswaldo Cruz》2007,102(4):539-540
A total of 74 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from three government hospitals in 2002 and 2003 were examined concerning the distribution of qacA/B gene, which is the determinant of resistance to quaternary ammonium compounds largely employed in hospital disinfection. By polymerase chain reaction the qacA/B gene was found in 80% of the isolates, which is a significant result considering it is the first time that qacA/B gene is being reported for Brazilian MRSA strains and it is presented at a high rate. 相似文献
79.
Lia Cecília de Lima Fvaro Welington Luiz Araújo Ednia Aparecida de Souza-Paccola Joo Lúcio Azevedo Luzia Doretto Paccola-Meirelles 《Mycological Research》2007,111(1):93-105
The fungus Colletotrichum sublineolum, causal agent of sorghum anthracnose, presents high variability, genetic instability and host specialization. The aims of the present work were to investigate the mechanisms involved in the genetic instability in this species. Mutants resistant to chlorate and unable to use nitrate (Nit mutants), were obtained spontaneously, isolated and characterized for complementation pattern, reversion frequency and RAPD profile. The results showed that chlorate-resistant mutants could be divided into six phenotypic classes that probably represented mutations in the structural nitrate reductase locus (nit1), in the structural nitrite reductase locus (nit6 and niiA of Neurospora and Aspergillus, respectively), in the specific regulator locus (nit3), in the main regulator locus (nit2), in loci that codified the cofactor containing molybdenum necessary for nitrate reductase activity (NitM), and one or more genes responsible for nitrate intake (crn). In addition, the genetic control of this metabolism in C. sublineolum seems to be similar to other fungi species such as Aspergillus, Neurospora and Fusarium. The high reversion frequency (10−4 to 10−5) presented by nit1 mutants suggests that the instability in evaluated strains could be a result of transposable elements activity. The RAPD analysis enabled confirmation that the Nit mutants have a similar genetic background to original strain, and that polymorphism exists among wild-type strains, nit1 mutants and revertants of C. sublineolum. These are important aspects for the later direction of molecular analysis, where these mutants will be used as a tool to isolate the active transposable elements in the C. sublineolum genome. 相似文献
80.
Luzia Neri C. Machado Nadir R. Marcondes Clarice Q. Fijimura Leite Adolfo C. Barreto Santos Fernando Rogério Pavan Vanessa Pietrowski Baldin Aline Lemes Castilho Vera Lúcia D. Siqueira Lilian Cristiane Baeza Henri Berghs Rosilene Fressatti Cardoso 《PloS one》2014,9(9)