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41.
Santos Lda S Fernandes VC Cruz SG Siqueira WC Goes AM Pedroso ER 《Memórias do Instituto Oswaldo Cruz》2012,107(1):1-10
The levels of total of IgG, IgG1, IgG2, IgG3 and IgG4 were evaluated in 54 patients with chronic paracoccidioidomycosis (PCM) before, during and after treatment using an enzyme-linked immunosorbent assay with Mexo and recombinant Pb27 (rPb27) as the antigens. Mexo was effective in distinguishing PCM patients from individuals in the negative control group (NC) based on total IgG and rPb27 performed worse than Mexo when these two groups were compared. IgG1, IgG2, IgG3 and IgG4 could not be used to clearly distinguish PCM patients from those in the NC group using either antigen. There was no clear relationship between antibody levels and the period of treatment. The majority of patients presented with decreased antibody levels during treatment, with no statistically significant differences among the different periods of treatment. Only IgG4 presented a negative correlation between its levels and clinical improvement during treatment. In total, 65% of untreated PCM patients showed reactivity against IgG4 when the Mexo antigen was used and this reactivity decreased over the course of treatment. There was a tendency towards decreasing antibody levels during treatment, but these antibody levels did not necessarily clear after the treatment was stopped. Mexo was useful for PCM diagnosis using total IgG; however, more studies are necessary before this antigen can be used in measuring the levels of total IgG and its subclasses for monitoring patients during treatment. 相似文献
42.
Sophie J. Bernelot Moens Sander I. van Leuven Kang H. Zheng Stefan R. Havik Miranda V. Versloot Leonie M. van Duivenvoorde Michael Hahne Erik S. G. Stroes Dominique L. Baeten Anouk A. J. Hamers 《PloS one》2016,11(11)
Studies on the role of B lymphocytes in atherosclerosis development, have yielded contradictory results. Whereas B lymphocyte-deficiency aggravates atherosclerosis in mice; depletion of mature B lymphocytes reduces atherosclerosis. These observations led to the notion that distinct B lymphocyte subsets have different roles. B1a lymphocytes exert an atheroprotective effect, which has been attributed to secretion of IgM, which can be deposited in atherosclerotic lesions thereby reducing necrotic core formation. Tumor necrosis factor (TNF)-family member ‘A Proliferation-Inducing Ligand’ (APRIL, also known as TNFSF13) was previously shown to increase serum IgM levels in a murine model. In this study, we investigated the effect of APRIL overexpression on advanced lesion formation and composition, IgM production and B cell phenotype. We crossed APRIL transgenic (APRIL-Tg) mice with ApoE knockout (ApoE-/-) mice. After a 12-week Western Type Diet, ApoE-/-APRIL-Tg mice and ApoE-/- littermates showed similar increases in body weight and lipid levels. Histologic evaluation showed no differences in lesion size, stage or necrotic area. However, smooth muscle cell (α-actin stain) content was increased in ApoE-/-APRIL-Tg mice, implying more stable lesions. In addition, increases in both plaque IgM deposition and plasma IgM levels were found in ApoE-/-APRIL-Tg mice compared with ApoE-/- mice. Flow cytometry revealed a concomitant increase in peritoneal B1a lymphocytes in ApoE-/-APRIL-Tg mice. This study shows that ApoE-/-APRIL-Tg mice have increased oxLDL-specific serum IgM levels, potentially mediated via an increase in B1a lymphocytes. Although no differences in lesion size were found, transgenic ApoE-/-APRIL-Tg mice do show potential plaque stabilizing features in advanced atherosclerotic lesions. 相似文献
43.
Christopher A. Mitchell John K. McGeachie Miranda D. Grounds 《Cell and tissue research》1992,269(1):159-166
Summary Skeletal muscle regeneration in SJL/J and BALB/c mice subjected to identical crush injuries is markedly different: in SJL/J mice myotubes almost completely replace damaged myofibres, whereas BALB/c mice develop fibrotic scar tissue and few myotubes. To determine the cellular changes which contribute to these differential responses to injury, samples of crushed tibialis anterior muscles taken from SJL/J and BALB/c mice between 1 and 10 days after injury were analysed by light and electron microscopy, and by autoradiography. Longitudinal muscle sections revealed about a 2-fold greater total mononuclear cell density in SJL/J than BALB/c mice at 2 to 3 days after injury. Electron micrographs identified a similar proportion of cell types at 3 days after injury. Autoradiographic studies showed that the proportions of replicating mononuclear cells in both strains were similar: therefore greater absolute numbers of cells (including muscle precursors and macrophages) were proliferating in SJL/J muscle. Removal of necrotic muscle debris in SJL/J mice was rapid and extensive, and by 6 to 8 days multinucleated myotubes occupied a large part of the lesion. By contrast, phagocytosis was less effective in BALB/c mice, myotube formation was minimal, and fibrotic tissue conspicuous. These data indicate that the increased mononuclear cell density, more efficient removal of necrotic muscle, together with a greater capacity for myotube formation in SJL/J mice, contribute to the more successful muscle regeneration seen after injury. 相似文献
44.
Jeff R. Powell Jeri L. Parrent Miranda M. Hart John N. Klironomos Matthias C. Rillig Hafiz Maherali 《Proceedings. Biological sciences / The Royal Society》2009,276(1676):4237-4245
The diversity of functional and life-history traits of organisms depends on adaptation as well as the legacy of shared ancestry. Although the evolution of traits in macro-organisms is well studied, relatively little is known about character evolution in micro-organisms. Here, we surveyed an ancient and ecologically important group of microbial plant symbionts, the arbuscular mycorrhizal (AM) fungi, and tested hypotheses about the evolution of functional and life-history traits. Variation in the extent of root and soil colonization by AM fungi is constrained to a few nodes basal to the most diverse groups within the phylum, with relatively little variation associated with recent divergences. We found no evidence for a trade-off in biomass allocated to root versus soil colonization in three published glasshouse experiments; rather these traits were positively correlated. Partial support was observed for correlated evolution between fungal colonization strategies and functional benefits of the symbiosis to host plants. The evolution of increased soil colonization was positively correlated with total plant biomass and shoot phosphorus content. Although the effect of AM fungi on infection by root pathogens was phylogenetically conserved, there was no evidence for correlated evolution between the extent of AM fungal root colonization and pathogen infection. Variability in colonization strategies evolved early in the diversification of AM fungi, and we propose that these strategies were influenced by functional interactions with host plants, resulting in an evolutionary stasis resembling trait conservatism. 相似文献
45.
Joya E. Nahon Menno Hoekstra Vanessa van Harmelen Patrick C.N. Rensen Ko Willems van Dijk Sander Kooijman Miranda Van Eck 《生物化学与生物物理学报:疾病的分子基础》2019,1865(2):494-501
Objective
Proteoglycan 4 (Prg4) has emerged from human association studies as a possible factor contributing to weight gain, dyslipidemia and insulin resistance. In the current study, we investigated the causal role of Prg4 in controlling lipid and glucose metabolism in mice.Methods
Prg4 knockout (KO) mice and wild-type (WT) littermates were challenged with an obesogenic high-fat diet (45% of total calories as fat) for 16?weeks. To further stimulate the development of metabolic alterations, 10% fructose water was provided starting from week 13.Results
Prg4 deficiency only tended to reduce diet-induced body weight gain, but significantly improved glucose handling (AUC: ?29%; p?<?0.05), which was also reflected by a tendency towards a reduced HOMA-IR score (?49%; p?=?0.06 as compared to WT mice). This coincided with lower hepatic expression of glycolysis (Gck: ?30%; p?<?0.05) and lipogenesis (Acc: ?21%; p?<?0.05 and Scd1: ?38%; p?<?0.001) genes, which translated in significantly lower hepatic triglyceride levels (?56%; p?<?0.001) in Prg4 KO mice as compared to WT mice. Prg4 KO mice likely had lower glucose utilization by skeletal muscle as compared to WT mice, judged by a significant reduction in the genes Glut4 (?29%; p?<?0.01), Pfkm (?21%; p?<?0.05) and Hk2 (?39%; p?<?0.001). Moreover, Prg4 KO mice showed a favorable white adipose tissue phenotype with lower uptake of triglyceride-derived fatty acids (?46%; p?<?0.05) and lower gene expression of inflammatory markers Cd68, Mcp1 and Tnfα (?65%, ?81% and ?63%, respectively; p?<?0.01) than WT mice.Conclusion
Prg4 KO mice are protected from high-fat diet-induced glucose intolerance and fatty liver disease. 相似文献46.
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49.
Antimicrobial activity of a bovine hemoglobin fragment in the tick Boophilus microplus. 总被引:7,自引:0,他引:7
A C Foga?a P I da Silva M T Miranda A G Bianchi A Miranda P E Ribolla S Daffre 《The Journal of biological chemistry》1999,274(36):25330-25334
Antifungal and antibacterial activities were detected in the hemolymph and gut contents of the cattle tick, Boophilus microplus. A peptide with antibacterial activity from the tick gut contents was purified to homogeneity by reversed-phase chromatography. The molecular mass of the purified peptide was 3,205.7 Da, measured by matrix-assisted laser desorption/ionization mass spectrometry. The amino acid sequence was obtained by Edman degradation and showed that the peptide was identical to a fragment of the bovine alpha-hemoglobin. A synthetic peptide based on the sequence obtained showed characterization data identical to those of the isolated material, confirming its structure. The synthetic peptide was active in micromolar concentrations against Gram-positive bacteria and fungi. These data led us to conclude that the antibacterial activity detected in tick gut contents is the result of enzymatic processing of a host protein, hemoglobin. This activity may be used by ticks as a defense against microorganisms. 相似文献
50.
Quini CC Américo MF Corá LA Calabresi MF Alvarez M Oliveira RB Miranda JR 《Journal of biological engineering》2012,6(1):6-6
ABSTRACT: AC Biosusceptometry (ACB) was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy. 相似文献