28 resultados para virulence markers
Resumo:
Bovine coronavirus has been associated with diarrhoea in newborn calves, winter dysentery in adult cattle and respiratory tract infections in calves and feedlot cattle. In Cuba, the presence of BCoV was first reported in 2006. Since then, sporadic outbreaks have continued to occur. This study was aimed at deepening the knowledge of the evolution, molecular markers of virulence and epidemiology of BCoV in Cuba. A total of 30 samples collected between 2009 and 2011 were used for PCR amplification and direct sequencing of partial or full S gene. Sequence comparison and phylogenetic studies were conducted using partial or complete S gene sequences as phylogenetic markers. All Cuban bovine coronavirus sequences were located in a single cluster supported by 100% bootstrap and 1.00 posterior probability values. The Cuban bovine coronavirus sequences were also clustered with the USA BCoV strains corresponding to the GenBank accession numbers EF424621 and EF424623, suggesting a common origin for these viruses. This phylogenetic cluster was also the only group of sequences in which no recombination events were detected. Of the 45 amino acid changes found in the Cuban strains, four were unique. (C) 2012 Elsevier B.V. All rights reserved.
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The wide spectrum of candidiasis and its clinical importance encourage the research with the purpose of clarifying the mechanisms of pathogenicity and identification of virulence factors of Candida sp. Therefore, the aim of this study was to verify the adhesion capacity, protease activity and genotypic diversity of oral C. albicans and C. tropicalis isolates. The adhesion ability to the extracellular matrix glycoproteins laminin and fibronectin was evaluated using the ELISA technique. The research of proteases was carried out in agar plate containing bovine albumin and through a quantitative method in buffer solution containing haemoglobin. Intra and interspecies polymorphisms was verified through random amplified polymorphic DNA (RAPD) technique. All C. albicans and C. tropicalis isolates binded to immobilised laminin and fibronectin. Ca33 and Ct13 isolates had relative adhesion index significantly higher than the other isolates for both glycoproteins (P < 0.001). Protease activity was observed in all isolates of C. albicans using either the semi-quantitative or quantitative assay. The protease activity of C. tropicalis was better detected through the quantitative assay. The genotypic diversity by RAPD revealed a heterogeneous population in both species. Nevertheless, C. tropicalis presented higher genetic variability than C. albicans strains.
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Different types of shed vesicles as, for example, exosomes, plasma-membrane-derived vesicles or microparticles, are the focus of intense research in view of their potential role in cell cell communication and under the perspective that they might be good tools for immunotherapy, vaccination or diagnostic purposes. This review discusses ways employed by pathogenic trypanosomatids to interact with the host by shedding vesicles that contain molecules important for the establishment of infection, as opposed to previous beliefs considering them as a waste of cellular metabolism. Trypanosomatids are compared with Apicomplexa, which circulate parasite antigens bound to vesicles shed by host cells. The knowledge of the origin and chemical composition of these different vesicles might lead to the understanding of the mechanisms that determine their biological function. (C) 2012 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.
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Premise of the study: Microsatellite markers were developed to study the genetic diversity and population structure of the carnivorous bladderwort Utricularia reniformis, which is endemic to the Atlantic Forest of southern and southeastern Brazil. Cross-species amplification was tested in U. gibba, U. neottioides, U. subulata, and Pinguicula benedicta. Methods and Results: The U. reniformis genome was sequenced in a 454 GS FLX sequencer, and eight primer sets were developed based on the microsatellites identified from the reads. All loci are polymorphic, showing 1.6 to 4.8 alleles per population. Preliminary results show that primer sets are suitable for population-level studies. Cross-species amplifi cation was successful in three other Utricularia species and one Pinguicula species. Conclusions: Markers developed in this study provide tools for analyses of intra- and interpopulation genetic diversity in Utricularia and Pinguicula.
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Premise of the study: Microsatellite markers were developed and characterized to investigate genetic diversity and gene flow and to help in conservation efforts for the endangered timber species Plathymenia reticulata. Methods and Results: Eleven microsatellite loci were characterized using 60 adult trees of two populations of P. reticulata from the Atlantic Forest of southern Bahia, Brazil. Of these, nine loci were polymorphic, with an average of 4.39 alleles per locus. The average expected heterozygosity per population ranged from 0.47 to 0.55. The combined exclusion probability was 0.99996. Conclusions: Our results reveal that the microsatellite markers developed in this study are an effective tool for paternity and genetic structure analysis that may be useful for conservation strategies.
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BACKGROUND/OBJECTIVES: This study examined the effect of weight loss after 3, 6 and 12 months of Roux-en-Y Gastric Bypass (RYGB) on energy intake and on several biomarkers of oxidative stress such as levels of vitamin C, beta-carotene, vitamin E (diet/blood), nitric oxide metabolites (NOx), myeloperoxidase (MPO), thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and activity of catalase (CAT). SUBJECTS/METHODS: Study with a control group (CG), assessed once, and a bariatric group (BG) assessed at the basal period as well as at 3, 6 and 12 months post-surgery; both groups were composed of 5 men and 31 women (n = 36). Age was 38.7 +/- 9.4 and 39.6 +/- 9.2 years old and body mass index (BMI) was 22.2 +/- 2.1 and 47.6 +/- 9.1 kg/m(2), respectively. The variance measure quoted was SEM. RESULTS: The body weight at 12 months was 35.8 +/- 1.0% (P<0.001) lower than that of the basal period. At the basal period BG showed higher levels of NOx (P=0.007) and TBARS (P<0.001) and lower levels of vitamins C and E (P<0.001) compared with CG. After 3 months the activity of MPO was decreased (P<0.001). Six months after surgery GSH levels were decreased (P=0.037), whereas CAT activity was increased (P=0.029). After 12 months levels of NOx (P=0.004), TBARS (P<0.001), beta-carotene (P<0.001) and vitamin E (P<0.001) were decreased, whereas those of vitamin C (P<0.001) were increased compared with controls. CONCLUSION: RYGB followed by a daily vitamin supplement apparently attenuated pro-inflammatory and oxidative stress markers 1 year after surgery, but additional antioxidant supplementation appears necessary.
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Validation of parentage and horse breed registries through DNA typing relies on estimates of random match probabilities with DNA profiles generated from multiple polymorphic loci. Of the twenty-seven microsatellite loci recommended by the International Society for Animal Genetics for parentage testing in Thoroughbred horses, eleven are located on five chromosomes. An important aspect in determining combined exclusion probabilities is the ascertainment of the genetic linkage status of syntenic markers, which may affect reliable use of the product rule in estimating random match probabilities. In principle, linked markers can be in gametic phase disequilibrium (GD). We aimed at determining the extent, by frequency and strength, of GD between the HTG4 and HMS3 multiallelic loci, syntenic on chromosome 9. We typed the qualified offspring (n (1) = 27; n (2) = 14) of two Quarter Bred stallions (registered by the Brazilian Association of Quarter Horse Breeders) and 121 unrelated horses from the same breed. In the 41 informative meioses analyzed, the frequency of recombination between the HTG4 and HMS3 loci was 0.27. Consistent with genetic map distances, this recombination rate does not fit to the theoretical distribution for independently segregated markers. We estimated sign-based D' coefficients as a measure of GD, and showed that the HTG4 and HMS3 loci are in significant, yet partial and weak, disequilibrium, with two allele pairs involved (HTG4*M/HMS3*P, D'(+) = 0.6274; and HTG4*K/HMS3*P, D'(-) = -0.6096). These results warn against the inadequate inclusion of genetically linked markers in the calculation of combined power of discrimination for Thoroughbred parentage validation.
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The objective of this study was to determine the frequencies of autoantibodies to heterogeneous islet-cell cytoplasmic antigens (ICA), glutamic acid decarboxylase(65) (GAD(65)A), insulinoma-associated antigen-2 (IA-2A) and insulin (IAA)-and human leukocyte antigen (HLA) class II markers (HLA-DR and -DQ) in first degree relatives of heterogeneous Brazilian patients with type I diabetes(T1DM). A major focus of this study was to determine the influence of age, gender, proband characteristics and ancestry on the prevalence of autoantibodies and HLA-DR and -DQ alleles on disease progression and genetic predisposition to T1DM among the first-degree relatives. IAA, ICA, GAD(65)A, IA-2A and HLA- class II alleles were determined in 546 first-degree-relatives, 244 siblings, 55 offspring and 233 parents of 178 Brazilian patients with T1DM. Overall, 8.9% of the relatives were positive for one or more autoantibodies. IAA was the only antibody detected in parents. GAD(65) was the most prevalent antibody in offspring and siblings as compared to parents and it was the sole antibody detected in offspring. Five siblings were positive for the IA-2 antibody. A significant number (62.1%) of siblings had 1 or 2 high risk HLA haplotypes. During a 4-year follow-up study, 5 siblings (expressing HLA-DR3 or -DR4 alleles) and 1 offspring positive for GAD(65)A progressed to diabetes. The data indicated that the GAD(65) and IA-2 antibodies were the strongest predictors of T1DM in our study population. The high risk HLA haplotypes alone were not predictive of progression to overt diabetes.
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Mesenchymal stem cells (MSCs) from human adipose tissue have a great potential for use in cell therapy due to their ease of isolation, expansion, and differentiation, besides the relative acceptance from the ethical point of view. Our intention was to isolate and promote in vitro expansion and differentiation of MSCs from human adipose tissue into cells with a pancreatic endocrine phenotype. Human adipose tissue obtained from patients undergoing abdominal dermolipectomy was digested with type I collagenase. MSCs isolated by plastic adherence and characterized by cytochemistry and FACS were expanded in vitro. MSC differentiation into an endocrine phenotype was induced over 2 to 4 months with high glucose (25 mmol/L) media containing nicotinamide, exendin-4, and 2-mercaptoethanol. Insulin and glucagon expressions were analyzed by immunofluorescence. Cells isolated from human adipose tissue and expanded in vitro expressed MSC markers as confirmed by FACS and cytochemistry. Insulin but not glucagon production by differentiated cells was demonstrated by irnmunofluorescence. MSCs isolated from human adipose tissue were induced to differentiate in vitro into an endocrine phenotype that expressed insulin
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Context: Periodontitis is the most common lytic disease of bone and is recognized as a common complication of diabetes. Lipid peroxidation (LPO) is increased in diabetes and may be related to modulation of the inflammatory response. LPO levels in patients with diabetes and periodontal disease have not been evaluated. Objective: The aim of this study was to evaluate the levels of LPO and its correlation with periodontal status and inflammatory cytokines in type 2 diabetic and nondiabetic patients. Design and Setting: This is a cross-sectional study involving Brazilian patients recruited at the State University of Sao Paulo. Patients: The sample comprised 120 patients divided into four groups based upon diabetic and dyslipidemic status: poorly controlled diabetics with dyslipidemia, well-controlled diabetics with dyslipidemia, normoglycemic individuals with dyslipidemia, and healthy individuals. Main Outcome Measures: Blood analyses were carried out for fasting plasma glucose, glycated hemoglobin, and lipid profile. Periodontal examinations were performed, and gingival crevicular fluid was collected. LPO levels were evaluated by measuring oxidized low-density lipoprotein (ELISA) and malondialdehyde (HPLC). Cytokines were evaluated by the multiplex bead technique. Results: LPO evaluated by malondialdehyde in plasma and gingival crevicular fluid was significantly increased in diabetes groups. Significant correlations between LPO markers and periodontal parameters indicate a direct relationship between these levels and the severity of inflammation and secretion of inflammatory cytokines, particularly in diabetic patients. Conclusion: These findings suggest an important association for LPO with the severity of the local inflammatory response to bacteria and the susceptibility to periodontal disease in diabetic patients. (J Clin Endocrinol Metab 97: E1353-E1362, 2012)
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Premise of the study: We developed and characterized nuclear microsatellite markers for Anadenanthera colubrina, a tropical tree species widely distributed in South America. Methods and Results: Leaf samples of mature A. colubrina trees, popularly called "angico," were collected from an area that is greatly impacted by agricultural practices in the region of Ribeirao Preto in Sao Paulo State in southeastern Brazil. Twenty simple sequence repeat (SSR) markers were developed, 14 of which had polymorphic loci. A total of 96 alleles were detected with an average of 6.86 alleles per polymorphic locus. The expected heterozygosity, calculated at polymorphic loci, ranged from 0.18 to 0.83. Finally, we demonstrated that 18 loci were cross-amplified in A. peregrina. Conclusions: A total of 14 polymorphic markers suggest a high potential for genetic diversity, gene flow, and mating system analyses in A. colubrina.
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Various organisms have been characterized by molecular methods, including fungi of the genus Cryptococcus. The purposes of this study were: to determine the discriminatory potential of the RAPD (Random Amplified Polymorphic DNA) primers, the pattern of similarity of the Cryptococcus species, and discuss their useful application in epidemiological studies. We analyzed 10 isolates of each specie/group: C. albidus, C. laurentii complex, C. neoformans var. grubii, all from environmental source, and two ATCC strains, C. neoformans var. grubii ATCC 90112, and C. neoformans var. neoformans ATCC 28957 by RAPD-PCR using the primers CAV1, CAV2, ZAP19, ZAP20, OPB11 and SEQ6. The primers showed a good discriminatory power, revealing important differences between them and between species; the SEQ6 primer discriminated a larger number of isolates of three species. Isolates of C. laurentii showed greater genetic diversity than other species revealed by all six primers. Isolates of C. neoformans were more homogeneous. Only the primer CAV2 showed no amplification of DNA bands for C. albidus. It was concluded that the use of limited number of carefully selected primers allowed the discrimination of different isolates, and some primers (e. g., CAV2 for C. albidus) may not to be applied to some species.
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Obesity and other chronic diseases are accompanied by adipose tissue, liver, pancreas, muscle and brain low-grade chronic inflammation. Indeed, the obese condition and metabolic syndrome are characterized by an increased expression of inflammatory cytokines and infiltration of immune cells in adipocytes. The inflammatory response promotes the activation of transcriptional factors and pro-inflammatory cytokines, which can lead to an unresolved inflammatory response associated with an inhibition of insulin signalling and high risk for cardiovascular events. Epidemiological and intervention studies have been carried out to find out dietary patterns, foods and bioactive compounds with protective anti-inflammatory actions. The most studied compounds are polyphenols, especially isoflavone and anthocyanin, but quercertin, catechin and resveratrol have also been investigated. Furthermore, some studies have reported the effects of milk peptides, plant sterol and stanol, L-carnitine and alpha-lipoic acid on inflammatory processes. This review aimed to collect and discuss those relevant studies reported in the scientific literature following a systematic scientific search about the effect of such bioactive compounds on inflammation in humans.