265 resultados para Biochemical characterization of various male morphotypes
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One of the main obstacles for understanding biological events involved in cancer is the lack of experimental models for in vitro studies especially for prostate cancer (PC).There are a limited number of PC cell lines being the majority originated from metastatic tumors mostly acquired from American Tissue Cell Culture which demands importation an expensive and bureaucratic process. Also it is well known that there are ethnic differences between populations concerning the behavior of tumors and the research based on cell lines derived from Brazilians should be interesting. Our aim was to develop tumor cell lines from primary PC.
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Leptospirosis is a worldwide zoonosis caused by pathogenic Leptospira. The whole-genome sequence of Leptospira interrogans serovar Copenhageni together with bioinformatic tools allow us to search for novel antigen candidates suitable for improved vaccines against leptospirosis. This study focused on three genes encoding conserved hypothetical proteins predicted to be exported to the outer membrane. The genes were amplified by PCR from six predominant pathogenic serovars in Brazil. The genes were cloned and expressed in Escherichia coli strain BL21-SI using the expression vector pDEST17. The recombinant proteins tagged with N-terminal 6xHis were purified by metal-charged chromatography. The proteins were recognized by antibodies present in sera from hamsters that were experimentally infected. Immunization of hamsters followed by challenge with a lethal dose of a virulent strain of Leptospira showed that the recombinant protein rLIC12730 afforded statistically significant protection to animals (44 %), followed by rLIC10494 (40 %) and rLIC12922 (30 %). Immunization with these proteins produced an increase in antibody titres during subsequent boosters, suggesting the involvement of a T-helper 2 response. Although more studies are needed, these data suggest that rLIC12730 and rLIC10494 are promising candidates for a multivalent vaccine for the prevention of leptospirosis.
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Background: CD8+ T cells and natural killer (NK) cells are involved in the immune response against some pathogens. For this purpose, we investigated the in situ paracoccidioidomycosis (PCM) immune response addressing the participation of NK cells, CD8+ T cells, perforin and granzyme B expression. Methods: Sixty biopsies of PCM skin and mucosa were classified according to the presence of compact granulomas (G1), poorly organized granulomas (G2) and both kinds in the same lesion (G3). CD8+ T cells, NK cells, perforin and granzyme B were showed by immunohistochemistry. Results: CD8+ T cells were increased over NK cells in cutaneous G1 and G2 lesions. There was no difference regarding such cells in G3 lesions, although they were abundant in such lesions. In mucosa, CD8+ T cells were increased in number over NK cells in all groups. Granzyme B in skin increased in G2 and G3. The number of granzyme did not differ in mucosal lesions in the three groups. Conclusions: CD8+ T cells and NK cells play a role in PCM cutaneous and mucosal lesions. The predominance of CD8+ T cells over NK cells may represent an effective response against the fungi. Moreover, the high number of granzyme B expressing cells corroborates this possibility.
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Rapid evolution and high intrahost sequence diversity are hallmarks of human and simian immunodeficiency virus (HIV/SIV) infection. Minor viral variants have important implications for drug resistance, receptor tropism, and immune evasion. Here, we used ultradeep pyrosequencing to sequence complete HIV/SIV genomes, detecting variants present at a frequency as low as 1%. This approach provides a more complete characterization of the viral population than is possible with conventional methods, revealing low-level drug resistance and detecting previously hidden changes in the viral population. While this work applies pyrosequencing to immunodeficiency viruses, this approach could be applied to virtually any viral pathogen.
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This work reports the first ultrastructural investigation into the degradation process that starch granules isolated from bananas (cv. Nanicao) undergo during ripening. Starch granules from green bananas had a smooth surface, while granules from ripe bananas were more elongated with parallel striations, as revealed by CSLM and SEM. AFM images revealed that the first layer covering the granule surface is composed of a hard material and, as degradation proceeds, hard and soft regions seem to be repeated at regular intervals. WAXD patterns of banana starches were C-type, and the crystalline index was reduced during ripening. The B-/A-type ratio was increased, indicating the preferential degradation of the A-type allomorph. The branch-chain length distribution showed predominantly short chains of amylopectin (A and B1-chain). The fa/fb ratio was reduced during degradation, while amylose content was increased. The results allowed a detailed understanding of the changes that starch granules undergo during banana ripening. (C) 2010 Elsevier Ltd. All rights reserved.
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Bladder cancer (BC) is the fourth most common cancer in the USA. In Brazil, BC represents 3% of the total existing carcinomas in the population and represents the second highest incidence among urological tumors. The majority of bladder cancer cell lines available were derived from Caucasians and established in the seventies or eighties. Thus, neoplasia development in these cells likely occurred in environment conditions vastly different than today. In the present study, we report the establishment and characterization of three Brazilian bladder cancer cell lines (BexBra1, BexBra2, and BexBra4). These cell lines may be helpful for dissecting the genetic and epigenetic aspects that trigger the progression of BC. Moreover, the development of a Brazilian representative of the disease will allow us to investigate the potential inter-racial differences of malignancy-associated phenotypes in bladder cancer.
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Pulp softening is one of the most remarkable changes during ripening of papaya (Carica papaya) fruit and it is a major cause for post-harvest losses. Although cell wall catabolism has a major influence on papaya fruit, quality information on the gene products involved in this process is limited. A full-length polygalacturonase cDNA (cpPG) was isolated from papaya pulp and used to study gene expression and enzyme activity during normal and ethylene-induced ripening and after exposure of the fruit to 1-MCP. Northern-blot analysis demonstrated that cpPG transcription was strongly induced during ripening and was highly ethylene-dependent. The accumulation of cpPG transcript was paralleled by enzyme activity, and inversely correlated to the pulp firmness. Preliminary in silica analysis of the cpPG genomic sequence revealed the occurrence of putative regulatory motifs in the promoter region that may help to explain the effects of plant hormones and non-abiotic stresses on papaya fruit firmness. This newly isolated cpPG is an important candidate for functional characterization and manipulation to control the process of pulp softening during papaya ripening. (C) 2009 Elsevier Masson SAS. All rights reserved.
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Type 1, X-linked Hyper-IgM syndrome (HIGM1) is caused by mutations in the gene encoding the CD154 protein, also known as CD40 ligand (CD40LG). CD40L is expressed in activated T cells and interacts with CD40 receptor expressed on B lymphocytes and dendritic cells. Affected patients present cellular and humoral immune defects, with infections by intracellular, opportunistic and extracellular pathogens. In the present study we investigated the molecular defects underlying disease in four patients with HIGM1. We identified four distinct CD40L mutations, two of them which have not been previously described. P1 harboured the novel p.G227X mutation which abolished CD40L expression. P2 had a previously described frame shift deletion in exon 2 (p.I53fsX65) which also prevented protein expression. P3 demonstrated the previously known p.V126D change in exon 4, affecting the TNF homology (TNFH) domain. Finally, P4 evidenced the novel p.F229L mutation also located in the TNFH domain. In silico analysis of F229L predicted the change to be pathological, affecting the many hydrophobic interactions of this residue. Precise molecular diagnosis in HIGM syndrome allows reliable detection of carriers, making genetic counselling and prenatal diagnosis possible.
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Purpose: The aim of this study was to characterize the first 48-hour evolution of metabolic acidosis of adult patients with diabetic ketoacidosis admitted to the intensive care unit. Materials and Methods: We studied 9 patients retrieved from our prospective collected database, using the physicochemical approach to acid-base disturbances. Results: Mean (SD) age was 34 (13) years; mean (SD) Acute Physiology and Chronic Health Evaluation II score was 16 (10); mean (SD) blood glucose level on admission was 480 (144) mg/dL; mean (SD) pH was 7.17 (0.18); and mean (SD) standard base excess was -16.8 (7.7) mEq/L. On admission, a great part of metabolic acidosis was attributed to unmeasured anions (strong ion gap [SIG], 20 +/- 10 mEq/L), with a wide range of strong ion difference (41 +/- 10 mEq/L). During the first 48 hours of treatment, 297 +/- 180 IU of insulin and 9240 +/- 6505 mL of fluids were used. Metabolic improvement was marked by the normalization of pH, partial correction of standard base excess, and a reduction of hyperglycemia. There was a significant improvement of SIG (7.6 +/- 6.2 mEq/L) and a worsening of strong ion difference acidosis (36 +/- 5 mEq/L) in the first 24 hours, with a trend toward recuperation between 24 and 48 hours (38 +/- 6 mEq/L). Conclusion: Initial metabolic acidosis was due to SIG, and the treatment was associated with a significant decrease of SIG with an elevation of serum chloride above the normal range. (C) 2011 Elsevier Inc. All rights reserved.
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Respiratory syncytial virus (RSV) is recognized as the leading cause of nosocomial respiratory infection among hematopoietic stem cell transplant (HSCT) recipients, causing considerable morbidity and mortality. RSV is easily transmitted by contact with contaminated surfaces, and in HSCT units, more than 50% of RSV infections have been characterized as of nosocomial origin. From April 2001 to October 2002, RSV was identified by direct immunofluorescent assay in 42 symptomatic HSCT recipients. Seven RSV strains from 2001 and 12 RSV strains from 2002 were sequenced. RNA extraction, cDNA synthesis, and seminested polymerase chain reaction (PCR) with primers complementary to RSV genes G and F were pet-formed. PCR products were analyzed by nucleotide sequencing of the C-terminal region of gene G for typing (in group A or B). Of the 7 strains analyzed in 2001, only 2 belonged to group B; the other 5 belonged to group A. Of these 7 strains, 3 were identical and were from recipients receiving outpatient care. In 2002, of the 12 strains analyzed, 3 belonged to group A and the other 9 belonged to group B. Of these 9 strains, 7 were genetically identical and were also from recipients receiving outpatient care. Therefore, multiple strains of RSV cocirculated in the hematopoietic stem cell transplant units (ward and outpatient units) between 2001 and 2002. Nosocomial transmission was more likely to occur at the HSCT outpatient unit than in the HSCT ward. Infection control practices should also be implemented in the outpatient setting.
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Few data are available on autopsy-proven fatal asthma patients in Sao Paulo, Brazil. We characterized 73 asthma patients who were autopsied at the Servico de Verificacao de Obitos do Universidade de Sao Paulo between 1996 and 2004. An interview with the next of kin assessed socioeconomic status, history, and treatment of asthma. There were 42 women and 31 men. Fifty-six (76.7%) of them were older than 34 years. Sixty-three percent were Caucasians, 77.3% had < 8 years of schooling, and the median income was 1.6 times the minimum wage. Twenty-two patients (30.1%) were smokers and 14 (19.2%) were ex-smokers. Only 25 (34.2%) patients were regularly followed by a doctor. Only 12.3% received inhaled steroids. Thirty-five patients (47.9%) had moderate-to-severe asthma. Fifty-five (75.3%) deaths took place outside a hospital, We conclude that this population shares characteristics of severe or poorly controlled asthma, low educational and socioeconomic levels, and lack of medical care and of inhaled steroid use.
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A shift in the activation of pulmonary macrophages characterized by an increase of IL-1, INF-alpha and IL-6 production has been induced in mice infected with Paracoccidioides brasiliensis. It is still unclear whether a functional shift in the resident alveolar macrophage population would be responsible for these observations due to the expression of cell surface molecules. We investigated pulmonary macrophages by flow cytometry from mice treated with P. brasiliensis derivatives by intratracheal route. In vivo labeling with the dye PKH26GL was applied to characterize newly recruited pulmonary macrophages from the bloodstream. Pulmonary macrophages from mice inflamed with P. brasiliensis derivatives showed a high expression of the surface antigens CD11b/CD18 and CD23 among several cellular markers. The expression of these markers indicated a pattern of activation of a subpopulation characterized as CD11b(+) or CD23(+), which was modulated in vitro by IFN-gamma and IL-4. Analysis of monocytes labelled with PKH26GL demonstrated that CD11b(+) cells did infiltrate the lung exhibiting a proinflammatoni pattern of activation, whereas CD23(+) cells were considered to be resident in the lung. These findings may contribute to better understand the pathology of lung inflammation caused by P. brasiliensis infection. (C) 2010 Elsevier GmbH. All rights reserved.
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Hydrocephalus is a common neurological problem in humans, Usually caused by an impairment of cerebrospinal fluid (CSF) flow or absorption. A reliable induced model of chronic hydrocephalus in mice would be useful to test hypotheses using genetic mutants. Our goal was to characterize behavioral and histological changes in juvenile and Young adult mice with kaolin (aluminum silicate) -induced hydrocephalus. Seven-day old and 7-8 week old mice received injection of kaolin into the cisterna magna. Behavior was assessed repeatedly. Seven or 14 days following kaolin, magnetic resonance (MR) imaging was used to assess ventricle size. In hydrocephalic mice, body weight was significantly lower than in age-matched saline-injected sham controls and the gait and posture score were impaired. Juvenile mice developed severe ventriculomegaly and had reduced corpus callosum thickness with gross white matter destruction by 14 days. Reactive astroglial change in white matter and cortex and reduced cellular proliferation in the subependymal zone were also apparent. Young adult mice developed only moderate ventricular enlargement without overt white matter destruction, although there was corpus callosum atrophy and mild astroglial reaction in white matter. Glial fibrillary acidic protein content was significantly higher in juvenile and young adult hydrocephalic mice at 7 and 14 days, but myelin basic protein content was not significantly altered. In conclusion, hydrocephalus induced by percutaneous injection of kaolin in juvenile and young adult mice is feasible. The associated periventricular alterations are essentially the same as those reported in rats of comparable ages. (C) 2009 Elsevier Inc. All rights reserved.
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Biochemical markers for remission on acromegaly activity are controversial. We studied a subset of treated acromegalic patients with discordant nadir GH levels after oral glucose tolerance test (oGTT) and IGF-I values to refine the current consensus on acromegaly remission. We also compared GH results by two GH immunoassays. From a cohort of 75 treated acromegalic patients, we studied 13 patients who presented an elevated IGF-I despite post-oGTT nadir GH of <= 1 mu g/l. The 12-h daytime GH profile (GH-12 h), nadir GH after oGTT, and basal IGF-I levels were studied in patients and controls. Bland-Altman method showed high concordance between GH assays. Acromegalic patients showed higher mean GH-12 h values (0.71+/-0.36 vs. 0.31+/-0.28 mu g/l; p<0.05) and nadir GH after oGTT (0.48+/-0.32 vs. 0.097+/-0.002 mu g/l; p<0.05) as compared to controls. Nadir GH correlated with mean GH-12 h (r=0.92, p<0.05). The mean GH-12 h value from upper 95% CI of controls (0.54 mu g/l) would correspond to a theoretical normal nadir GH of <= 0.27 mu g/l. Patients with GH nadir <= 0.3 mu g/l had IGF-I between 100-130% ULNR (percentage of upper limit of normal range) and mean GH-12 h of 0.35+/-0.15, and patients with GH nadir >0.3 and <= 1 mu g/l had IGF-I >130% ULNR and mean GH-12 h of 0.93+/-0.24 mu g/l. Our data integrate daytime GH secretion, nadir GH after oGTT, and plasma IGF-I concentrations showing a continuum of mild residual activity in a subgroup of treated acromegaly with nadir GH values <= 1 mu g/l. The degree of increased IGF-I levels and nadir GH after oGTT are correlated with the subtle abnormalities of daytime GH secretion.
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The Wistar Audiogenic Rat (WAR) strain is a genetic model of sound-induced reflex epilepsy which was selected starting from audiogenic seizures susceptible Wistar rats. Wistar resistant rats were used as WAR`s control in this study. In the acute situation, audiogenic seizures (AS) in WARs mimic tonic-clonic seizures and, in the chronic protocol, mimic temporal lobe epilepsy. AS have been shown to evoke neuroendocrine responses; however, the hypothalamic-pituitary-adrenal activity in the WAR has not been established. The aim of this study was to evaluate the hypothalamic-pituitary-adrenal axis (HPA) responses to exogenous ACTH stimulation (8 ng/rat), fifteen minute restraint stress and circadian variation (8 am and 8 pm) under rest conditions in these animals through plasma measurements of ACTH and corticosterone concentrations. We also measured the body weight from birth to the 9th week of life and determined adrenal gland weight. We found that WARs are smaller than Wistar and presented a higher adrenal gland weight with a higher level of corticosterone release after intravenous ACTH injection. They also showed altered HPA axis circadian rhythms and responses to restraint stress. Our data indicate that, despite the lower body weight, WARs have increased adrenal gland weight associated with enhanced pituitary and adrenal responsiveness after HPA axis stimulation. Thus, we propose WARs as a model to study stress-epilepsy interactions and epilepsy-neuropsychiatry comorbidities. (C) 2011 Elsevier B.V. All rights reserved.