207 resultados para Common Beta-subunit


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Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher`s disease, the most common inherited storage disorder. Treatment consists of enzyme replacement therapy by the administration of recombinant GCR produced in Chinese hamster ovary cells. The production of anti-GCR antibodies has already been described with placenta-derived human GCR that requires successive chromatographic procedures. Here, we report a practical and efficient method to obtain anti-GCR polyclonal antibodies against recombinant GCR produced in Escherichia coli and further purified by a single step through nickel affinity chromatography. The purified GCR was used to immunize BALB/c mice and the induction of anti-GCR antibodies was evaluated by enzyme-linked immunosorbent assay. The specificity of the antiserum was also evaluated by western blot analysis against recombinant GCR produced by COS-7 cells or against endogenous GCR of human cell lines. GCR was strongly recognized by the produced antibodies, either as cell-associated or as secreted forms. The detected molecular masses of 59-66 kDa are in accordance to the expected size for glycosylated GCR. The GCR produced in E. coli would facilitate the production of polyclonal (shown here) and monoclonal antibodies and their use in the characterization of new biosimilar recombinant GCRs coming in the near future.

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The objective was to evaluate the effect of beta-lactoglobulin (beta-lg) polymorphism and seasonality on milk composition (fat, lactose, total solids, milk urea nitrogen, total protein, true protein, casein and somatic cell counts) of Holstein and Girolando cows. Milk and blood samples from 278 Holsteins cows and 156 Girolando cows were taken during two dry seasons and two rainy seasons, for milk composition analysis and to determine beta-lg genotypes, respectively. BB genotype was the most frequent for both breeds, followed by AA genotype for Holstein (BB>AA>AB) and by AB for Girolando cows (BB>AB>AA). No differences were found in milk compositional characteristics among genetic variants of beta-lg (AA, AB and BB) either between Holstein or Girolando cows. No association between milk composition and beta-lg genetic polymorphism was observed. During the dry season, independently of the breed considered, higher contents of lactose, true protein, casein and casein :true protein ratio were found.

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Simple, rapid and stable sperm evaluation methods which have been optimized for common marmoset (Callithrix jacchus) are critical for studies involving collection and evaluation of sperm in the field. This is particularly important for new species groups such as Callitrichidae where the sperm have been little studied. Of this family, C jacchus is the best known, and has been chosen as a model species for other members of the genus Callithrix. The fundamental evaluation parameters for sperm of any species are viability and acrosomal status. Semen samples were collected by penile vibratory stimulation. To evaluate sperm plasma membrane integrity, Eosin-Nigrosin was tested here for the common marmoset sperm to be used under field conditions. Further, a non-fluorescent stain for acrosome, the ""Simple"" stain, developed for domestic and wild cats, was tested on common marmoset sperm. This was compared with a fluorescent staining, Fluorescein isothiocyanate-Pisum sativum agglutinin (FITC-PSA), routinely used and validated for common marmoset at the German Primate Centre to evaluate acrosomal integrity. Results obtained with the ""Simple"" stain showed a marked differentiation between sperm with intact and non-intact acrosome both with and without ionophore treatment and closely correlated with results obtained with FITC-PSA. Temperature had no effect on the results with the ""Simple"" stain and the complete processing is simple enough to be carried out under field conditions. These findings indicated that the ""Simple"" stain and Eosin-Nigrosin provide rapid and accurate results for C. jacchus sperm and that those methods can be reliably used as field tools for sperm evaluation for this species. (c) 2008 Elsevier Inc. All rights reserved.

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During the process of maturation in the oviduct, canine oocytes in the germinal vesicle stage are exposed to decreasing levels of estradiol-17 beta and increasing levels of progesterone. However, hormone concentrations in the microenvironments in which they act are higher than serum concentrations. Therefore, the aim of the present study was to compare the meiotic competence of canine oocytes harvested from anestrous bitches in culture medium containing high concentrations (20 mu g ml(-1)) of estradiol-17 beta and/or progesterone in association to gonadotropins (luteinizing hormone and follicle-stimulating hormone) using three different maturation periods (48, 72, and 96 h). Oocytes were cultured in tissue culture medium (TCM-199) and arranged in four experimental groups: group control, group E2 (estradiol-17 beta), group P4 (progesterone), and group E2 + P4. Regardless of the maturation period, groups P4 and E2 + P4 presented statistically higher rate of germinal vesicle breakdown oocytes compared to the group control and group E2. There were no significant differences among groups on germinal vesicle, metaphase I, metaphase II, and degenerated or unidentifiable oocytes rates. The mean percentage of metaphase II oocytes was higher at 96 h when compared to 72 h. Results of the present research indicate no influence of estradiol-17 beta supplementation, unless in association with progesterone. There is an evidence of the positive effect of progesterone on germinal vesicle breakdown. Results also showed that extended periods of in vitro maturation affect positively maturation rates to metaphase II of low competent oocytes harvested from anestrous bitches, independent of the maturation media. In conclusion, high concentrations of steroids, especially progesterone, have positive effect on in vitro oocyte maturation when the oocytes are derived from the anestrous status.

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Morphogenesis of salivary glands involves complex coordinated events. Synchronisation between cell proliferation, polarisation and differentiation, which are dependent on epithelial-mesenchymal interactions and on the microenvironment, is a requirement. Growth factors mediate many of these orchestrated biological processes and transforming growth factor-beta (TGF-beta) appear to be relevant. Using immunohistochemistry and immunofluorescence, we have mapped the distribution of TGF-beta 1, 2 and 3 and compared it with the expression of maturation markers in human salivary glands obtained from foetuses ranging from weeks 4 to 24 of gestation. TGF-beta 1 first appeared during canalisation stage in the surrounding mesenchyme and, in the more differentiated stages, was expressed in the cytoplasm of acinar cells throughout the adult gland. TGF-beta 2 was detected since the bud stage of the salivary gland. Its expression was observed in ductal cells and increased along gland differentiation, TGF-beta 3 was detected from the canalisation stage of the salivary gland, being weakly expressed on ductal cells, and it was the only factor detected on myoepithelial cells. The data suggest that TGF-beta have a role to play in salivary gland development and differentiation.

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beta-Catenin is a bifunctional protein related to cell adhesion and gene transcription when activated by Wnt pathway. Altered expression of beta-catenin was related to loss of differentiation, more aggressive phenotype, increase of tumor invasion, and poor prognosis in a number of different cancers. Actinic cheilitis is caused by excessive exposure to ultraviolet radiation and has a high potential to suffer malignant transformation into squamous cell carcinoma (SCC) of the lip, the most frequent oral malignancy. Studies of oral cancer have shown the correlation of beta-catenin expression and oral SCC prognosis, and loss of membrane expression may be considered as a potential marker for early tumor recurrence. Thirty-five cases of actinic cheilitis and 12 cases of SCC of the lip were select and submitted to immunohistochemical staining using beta-catenin antibody. beta-Catenin was positive on the membrane for all cases. Eighty-five percent of actinic cheilitis cases showed cytoplasmatic staining, and 22% nuclear staining. Eighty-three percent of SCC was positive for beta-catenin, and none of them had nuclear staining. Cytoplasmatic and nuclear staining of beta-catenin on studied cases point to pathway alterations. Results demonstrated that beta-catenin expression is altered on epithelial dysplasia, and it is related to degree of alterations. (C) 2011 Elsevier Inc. All rights reserved.

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Background: Galectin-3 has been implicated in tumor progression of some malignancies as thyroid, prostate, and salivary gland tumors. Recently, it has been suggested that this protein may be an important mediator of the beta-catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, the present study aimed to correlate galectin-3 expression with beta-catenin and cyclin D1 expressions in adenoid cystic carcinoma (ACC) and in polymorphous low-grade adenocarcinoma (PLGA). Methods: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of Sao Paulo and the proteins were analyzed by immunohistochemistry. Results: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for beta-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC (P < 0.05). Conclusions: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although beta-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.

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Background: Oncogenic Wnt/beta-catenin signaling occurs in numerous types of cancers, but little is known about the role of the Wnt protein family member, WNT-5A, in lip carcinogenesis. The aim of this study was to investigate WNT-5A, beta-catenin, and matrix metalloproteinase (MMP)-3 protein expression in actinic cheilitis (AC), and lip squamous cell carcinoma (LSCC). Methods: Twenty-one cases of AC, and fifty-one cases of LSCC were analyzed, with normal lip mucosa used as a control. Qualitative and semi-quantitative analyses of WNT-5A, beta-catenin, and MMP-3 immunostaining pattern and cellular distribution were performed. Results: WNT-5A was observed in more than 50% of the cells, scattered in all layers of AC, in contrast to the absence of immunostaining in normal lip mucosa. AC presented a higher level of WNT-5A expression than LSCC (P = 0.0289, Fisher test), while MMP-3 immunoexpression was statistically more significant in LSCC than in AC (P = 0.0285, Fisher test). Immunolabeling of beta-catenin protein was differentially distributed between samples; the majority of AC cases (61.90%) demonstrated a membranous-cytoplasmic pattern, while a considerable number of LSCC cases (29.41%) revealed a cytoplasmic pattern, instead of the usual membranous pattern. Conclusions: The present results suggest that WNT-5A may be an important marker during initial events of AC malignant transformation, in which non-canonical and canonical Wnt/beta-catenin signaling pathways could be involved. Additionally, WNT-5A might recruit other events in LSCC, such as MMP-3 protein synthesis, as its presence is increased in established malignant processes without beta-catenin dependency.

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Paracoccidioidomycosis, the major systemic mycosis in Latin America, is caused by the thermally dimorphic fungus Paracoccidioides brasiliensis. To investigate the role of interleukin (IL)-12 in this disease, IL-12p40(-/-) deficient mice (IL-12p40(-/-)) and wild type mice (WT) were infected intravenously with viable yeast cells of P. brasiliensis 18 isolate. We found that, unlike WT mice, IL-12p40(-/-) mice did not control fungal proliferation and dissemination and succumbed to infection by day 21 after inoculation. Additionally, IL-12p40(-/-) mice presented a higher number of granulomas/mm(2) in lung tissue than WT mice, and showed unorganized granulomas containing high numbers of yeast cells. Moreover, IL-12p40(-/-) mice did not release detectable levels of IFN-gamma, but they produced high levels of IL-10, as well as IgG1 antibody. Additionally, splenocytes from both infected IL-12p40(-/-) and WT mice exhibited a suppressed Con-A-induced T cell proliferative response. Our findings suggest that the IL-12p40 subunit mediates resistance in paracoccidioidomycosis by inducting IFN-gamma production and a Th1 immune response

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Studies investigating the immunopathological aspects of Jorge Lobo`s disease have shown that the inflammatory infiltrate consists mainly of histiocytes and multinucleated giant cells involving numerous yeast-like cells of Lacazia loboi, with the T lymphocytes more common than B lymphocytes and plasma cells. The quantification of cytokines in peripheral blood mononuclear cells culture supernatant has revealed alterations in the cytokines profile, characterized by predominance of a Th2 profile. In view of these findings and of the role of cytokines in cell interactions, the objective of the present study was to investigate the presence of the cytokines IL-10, TGF-ss 1 and TNF-alpha, as well as iNOS enzyme in granulomas induced by L. loboi. Histological sections obtained from skin lesions of 16 patients were analyzed by immunohistochemistry for the presence of these cytokines and iNOS. The results showed that TGF-ss 1 was the cytokine most frequently expressed by cells present in the inflammatory infiltrate, followed by IL-10. There was a minimum to discrete positivity of cells expressing TNF-alpha and iNOS. The results suggest that the presence of immunosuppressive cytokines in skin lesions of patients with the mycosis might be responsible for the lack of containment of the pathogen as demonstrated by the presence of numerous fungi in the granuloma.

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Rafacho A, Cestari TM, Taboga SR, Boschero AC, Bosqueiro JR. High doses of dexamethasone induce increased beta-cell proliferation in pancreatic rat islets. Am J Physiol Endocrinol Metab 296: E681-E689, 2009. First published January 21, 2009; doi:10.1152/ajpendo.90931.2008.-Activation of insulin signaling and cell cycle intermediates is required for adult beta-cell proliferation. Here, we report a model to study beta-cell proliferation in living rats by administering three different doses of dexamethasone (0.1, 0.5, and 1.0 mg/kg ip, DEX 0.1, DEX 0.5, and DEX 1.0, respectively) for 5 days. Insulin sensitivity, insulin secretion, and histomorphometric data were investigated. Western blotting was used to analyze the levels of proteins related to the control of beta-cell growth. DEX 1.0 rats, which present moderate hyperglycemia and marked hyperinsulinemia, exhibited a 5.1-fold increase in beta-cell proliferation and an increase (17%) in beta-cell size, with significant increase in beta-cell mass, compared with control rats. The hyperinsulinemic but euglycemic DEX 0.5 rats also showed a significant 3.6-fold increase in beta-cell proliferation. However, DEX 0.1 rats, which exhibited the lowest degree of insulin resistance, compensate for insulin demand by improving only islet function. Activation of the insulin receptor substrate 2/phosphatidylinositol 3-kinase/serine-threoninekinase/ribosomalprotein S6 kinase pathway, as well as protein retinoblastoma in islets from DEX 1.0 and DEX 0.5, but not in DEX 0.1, rats was also observed. Therefore, increasing doses of dexamethasone induce three different degrees of insulin requirement in living rats, serving as a model to investigate compensatory beta-cell alterations. Augmented beta-cell mass involves beta-cell hyperplasia and, to a lower extent, beta-cell hypertrophy. We suggest that alterations in circulating insulin and, to a lesser extent, glucose levels could be the major stimuli for beta-cell proliferation in the dexamethasone-induced insulin resistance.

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Locus coeruleus (LC) is involved in the LHRH regulation by gonadal steroids. We investigated the expression of progesterone and estrogen receptors (PR; ER) in LC neurons of ER alpha (alpha ERKO) or ER beta (beta ERKO) knockout mice, and their wild-type (alpha WT and beta WT). Immunocytochemical studies showed that LC expresses PR and both ERs, although ER beta was more abundant. Estradiol benzoate (EB) decreased ER alpha-positive cells in WT and beta ERKO mice, and progesterone caused a further reduction, whereas none of the steroids influenced ER beta expression. ER beta deletion increased ER alpha while ER alpha deletion did not alter ER beta expression. In both WT mice, EB increased PR expression, which was diminished by progesterone. These steroid effects were also observed in alpha ERKO animals but to a lesser extent, suggesting that ER alpha is partially responsible for the estrogenic induction of PR in LC. Steroid effects on PR in beta ERKO mice were similar to those in the alpha ERKO but to a lesser extent, probably because PR expression was already high in the oil-treated group. This expression seems to be specific of LC neurons, since it was not observed in other areas studied, the preoptic area and ventromedial nucleus of hypothalamus. These findings show that LC in mice expresses alpha ER, beta ER, and PR, and that a balance between them may be critical for the physiological control of reproductive function.