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71.
Rocha AM Rocha GA Santos A de Oliveira CA Queiroz DM 《Journal of clinical microbiology》2003,41(1):447-448
We validated a commercial enzyme-linked immunosorbent assay for the detection of anti-CagA antibodies in Brazilian patients with Helicobacter pylori infection. The test presented high sensitivity (97.4%) and specificity (88.9%) when employed in patients without gastric carcinoma. However, in gastric carcinoma patients, the test was neither sensitive nor specific enough to detect cagA-positive H. pylori infection. 相似文献
72.
Neves NA Carvalho LP De Oliveira MA Giraldo PC Bacellar O Cruz AA Carvalho EM 《Clinical and experimental immunology》2005,142(1):167-171
To determine whether there is an association between atopy and recurrent vaginal candidiasis (RVC) and to evaluate the type-2 immune response in patients with RVC. Evaluation of immediate hypersensitivity skin tests to aeroallergens, measurement of total IgE and Candida albicans specific IgE and levels of IL-5 in 44 women with RVC and 26 with sporadic vaginal candidiasis (SVC). Statistical analyses were performed by Mann-Whitney test and chi(2) test with Yates correction. History of atopy (68%) and positive skin test (42%) were higher (P < 0.05) in RVC than in patients with SVC. No significant difference was found in total IgE, C. albicans specific IgE and IL-5 levels. There was a strong association between atopy and RVC, but type-2 immune response to C. albicans antigen was absent or similar in the two groups of patients. 相似文献
73.
Pinheiro PS Rodrigues RJ Silva AP Cunha RA Oliveira CR Malva JO 《Neuroscience letters》2003,336(2):97-100
Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors have been identified mostly as postsynaptic receptors mediating fast glutamatergic synaptic transmission. However, neurochemical studies based on the modulation of neurotransmitter release have suggested the existence of presynaptic AMPA receptors. We have used a recently described technique that allows a high-purity fractionation of the pre- and postsynaptic proteins of synaptic junctions to evaluate the distribution of the different AMPA receptor subunits in rat hippocampal synapses. Surprisingly, we found very high levels of GluR1- and GluR2/3-like immunoreactivity in the presynaptic fraction, but also in the postsynaptic and extrasynaptic fractions. GluR4-like immunoreactivity was much less abundant but was still detected, predominantly in the postsynaptic fraction. This methodology appears to be far more sensitive than the classical immunogold electron microscopy to determine the localization of synaptic receptors. 相似文献
74.
75.
Andreo JC Oliveira JA Navarro JA Roque DD Roque JS Buchain RL 《Okajimas folia anatomica Japonica》2002,79(1):33-41
Samples of the anterior and posterior regions of the masseter and temporal muscles and of the anterior belly of the digastric muscle of 4 adult male tufted capuchin monkeys (Cebus apella) were removed and stained with HE and submitted to the m-ATPase reaction (with alkaline and acid preincubation) and to the NADH-TR and SDH reactions. The results of the histoenzymologic reactions were similar, except for acid reversal which did not occur in fibers of the fast glycolytic (FG) type in the mandibular locomotor muscles. FG fibers had a larger area and were more frequent in all regions studied. No significant differences in frequency or area of each fiber type were detected, considering the anterior and posterior regions of the masseter and temporal muscles. The frequency of fibers of the fast oxidative glycolytic (FOG) and slow oxidative (SO) types and of FOG area differed significantly between the anterior belly of the digastric muscle and the mandibular locomotor muscle. The predominance of fast twitch (FG and FOG) fibers and the multipenniform and bipenniform internal architecture of the masseter and temporal muscles, respectively, are characteristics that permit the powerful bite typical of tufted capuchin monkeys. 相似文献
76.
The strain difference in the effect of mercuric chloride on antigen-triggered serotonin release from rat mast cells is not mediated via interferon-gamma. 下载免费PDF全文
Previous work has shown that in vitro exposure of Brown-Norway (BN) rat peritoneal mast cells to mercuric chloride (HgCl2) causes enhancement of subsequent mediator release induced by cross-linking of surface immunoglobulin E (IgE). This enhancing effect is seen significantly less often with peritoneal cells from Lewis rats. In addition HgCl2 has been shown to suppress interferon (IFN)-gamma production by BN but not Lewis splenocytes. Given that IFN-gamma is known to inhibit mediator release by mast cells, we hypothesized that the strain difference in the effect of HgCl2 on mediator release was mediated via a differential effect on IFN-gamma release from T cells in the mixed peritoneal cell population: IFN-gamma release would be suppressed in the case of the BN rat, releasing the mast cells from inhibition and resulting in the enhancing effect of HgCl2. The aim of the study was to test two predictions of this hypothesis. Exposure of BN rat mast cells to IFN-gamma inhibited subsequent antigen-induced mediator release but did not significantly reduce HgCl2-mediated enhancement of this release. Exposure of Lewis rat mast cells to blocking concentrations of anti-IFN-gamma did not reveal any HgCl2-mediated enhancement of mediator release. These observations provide strong evidence against the hypothesis that the differential effects of HgCl2 on BN and Lewis rat mast cells are mediated via IFN-gamma. In addition the results revealed that BN rat mast cells are significantly more sensitive than Lewis rat mast cells to the inhibitory effects of IFN-gamma on antigen-induced mediator release. 相似文献
77.
78.
Silviene Fabiana De Oliveira Eliane Barbosa Dos Santos Patrícia Jeanne De Souza Mendona Daniela Cristiane Da Cruz Rocha Sidney Emanuel Batista Dos Santos 《American journal of human biology》2001,13(6):718-720
The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
79.
Ogawa K St John M Luiza de Oliveira M Arnold L Shirai T Sun TT Cohen SM 《Toxicologic pathology》1999,27(6):645-651
The expression of uroplakins, the tissue-specific and differentiation-dependent membrane proteins of the urothelium, was analyzed immunohistochemically in N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-treated rats and mice during bladder carcinogenesis. Male Fischer 344 rats were treated with 0.05% BBN in the drinking water for 10 wk and were euthanatized at week 20 of the experiment. BBN was administered to male B6D2F, mice; it was either provided at a rate of 0.05% in the drinking water (for 26 wk) or 5 mg BBN was administered by intragastric gavage twice weekly for 10 wk, followed by 20 wk without treatment. In rats, BBN-induced, noninvasive, low-grade, papillary, transitional cell carcinoma (TCC) showed decreased uroplakin-staining of cells lining the lumen but showed increased expression in some nonluminal cells. In mice, nonpapillary, high-grade dysplasia, carcinoma in situ, and invasive carcinoma were induced. There was a marked decrease in the number of uroplakin-positive cells lining the lumen and in nonluminal cells. This occurred in normal-appearing urothelium in BBN-treated mice and in dysplasic urothelium, in carcinoma in situ, and in invasive TCC. The percentage of uroplakin-positive nonluminal cells was higher in control mice than in rats, but it was lower in the mouse than in the rat after BBN treatment. Uroplakin expression was disorderly and focal in BBN-treated urothelium in both species. These results indicate that BBN treatment changed the expression of uroplakins during bladder carcinogenesis, with differences in rats and mice being related to degree of tumor differentiation. 相似文献
80.