70 research outputs found

    Cytogenetics and sperm ultrastructure of Atelopus spumarius (Anura, Bufonidae) from the Brazilian Amazon

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    The current taxonomy of most Atelopus species is based on morphological and color data only. Recent studies suggest that A. spumarius may represent a species complex assigned under the same name. Karyotypic data and description of sperm ultrastructure for 13 specimens of A. spumarius are presented here for the first time. A chromosomal analysis revealed 2n = 22 chromosomes, with centromeric heterochromatin in all pairs and a nucleolar organizer region (NOR) on the telomere of pair 7. The sperm was of the bufonoid type, presenting a filiform nucleus covered by an acrosomal complex and a mitochondrial collar in the neck region. The tail was composed of an axoneme, an undulating membrane and an axial rod. A karyotype analysis of A. spumarius showed the same chromosome number and similar chromosomal morphology as described for congeneric species, with slight differences probably resulting from pericentric inversions. The NOR location (on pair 7) was the same as that observed for species belonging to the genus Rhinella. The spermatological findings indicate a close relationship between Atelopus and the bufonoid lineage. The present data are useful for reference in future studies to determine whether more than one species are assigned to A. spumarius.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Estadual de Campinas Instituto de Biologia Departamento de Biologia Estrutural e FuncionalUniversidade Estadual do Sudoeste da Bahia Departamento de Ciências BiológicasUniversidade Federal de São Paulo (UNIFESP) Departamento de BiociênciasInstituto Nacional de Pesquisas da Amazônia Coordenadoria de Pesquisa em EcologiaUNIFESP, Depto. de BiociênciasSciEL

    Analysis of male reproductive parameters in a murine model of mucopolysaccharidosis type I (MPS I)

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    Mucopolysaccharidosis (MPS) I is a lysosomal storage disorder (LSD) that is characterised by alpha-L-idu-ronidase (Idua) deficiency and continuous deposition of glycosaminoglycans (GAGs), which consequently interferes with cell signalling mechanisms and results in multisystemic and progressive symptoms. The animal model of MPS I (Idua-/-) has been widely studied to elucidate the consequences and progression of the disorder; however, studies specifically assessing the male reproductive tract are lacking. The aim of this study was to evaluate some of the reproductive characteristics of male MPS I mice in two phases of life. Reproductive organ biometry, sperm counts, sperm morphological evaluation, plasma testosterone measurements and histopathological, histomorphometrical and immunohistochemical analysis were performed in 3- and 6-month-old C57BL/6 Idua+/+ and Idua-/- mice. Seminal vesicle weights were decreased in both the 3- and 6-month-old Idua-/- mice. Decrease in sperm counts and the majority of the histopathological signs were observed in the 6-month-old Idua-/- mice. No differences were detected in the sperm morphological analysis. Immunohistochemistry revealed that seminiferous tubules from 3-month-old Idua-/- mice were more intensely stained with anti-caspase-3 than 3-month-old Idua+/+ mice, but no difference was found at 6 months. These results suggest that MPS I interferes with male reproductive parameters both in 3 and 6-month-old animals and histopathological signs are more pronounced in 6-month-old mice, indicating that the effects of the disorder may intensify with the disease progression.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)AFIPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ Fed Sao Paulo, Dept Psychobiol, BR-04024002 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Psychobiol, BR-04024002 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilWeb of Scienc

    Prebiotic and Synbiotic Modifications of Beta Oxidation and Lipogenic Gene Expression after Experimental Hypercholesterolemia in Rat Liver

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    Background and aims: Non-alcoholic fatty liver disease (NAFLD) is characterized by the presence of fat in hepatocytes because of decreased β-oxidation and increased lipogenesis. Prebiotics, probiotics, and synbiotic have modulatory effects on intestinal microbiota and may influence the gut-liver axis. Our aim was to evaluate the effects of prebiotic, probiotics, and synbiotic on liver histopathology and gene expression related to β-oxidation and lipogenesis after hypercholesterolemia. Methods: Wistar male adult rats (n = 40) were submitted to hypercholesterolemic conditions (HPC) (60 days). On Day 30 of HPC, rats were subdivided in 5 groups: negative control (NC): without HPC + Gv (distilled water); positive control (PC): with HPC + Gv (distilled water); prebiotic (PRE): HPC + Gv with prebiotic (Fiber FOS®); probiotic (PRO): HPC + Gv with probiotic strains Gv (Probiatop®); and synbiotic (SYN): HPC + Gv with synbiotic (Simbioflora®). All rats were sacrificed on Day 30 post-treatment. Blood was collected to verify total serum cholesterol, and liver tissue was sampled to verify histopathological changes and gene expression. Gene expression related to ß-oxidation (PPAR-α and CPT-1) and lipogenesis (SREBP-1c, FAS and ME) was evaluated in liver tissue using RT-qPCR. Results: PC had higher cholesterol levels when compared to NC. PRE and SYN rats had lower cholesterol levels than PC. PC rats showed more histopathological changes than NC rats; PRE and SYN rats showed fewer alterations than PC rats. PPAR-α was expressed at higher levels in SYN and PC rats compared with PRE and PRO rats. CPT-1 expression was similar in all groups. SREBP-1c was expressed at higher levels in PC rats compared with NC rats; levels were lower in SYN rats compared with PRO rats; levels were lower in PRE rats compared with PC and PRO rats. FAS was expressed at lower levels in PRE rats compared with SYN rats. ME expression was lower in PC rats compared with NC rats. Conclusion: Prebiotic and synbiotic supplementation improve hepatic alterations related to hypercholesterolemia. These changes appear to be mediated by altered expression of genes related to β-oxidation and lipogenesis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Fed Sao Paulo, Dept Biosci, Santos, BrazilUniv Sao Paulo, Dept Gastroenterol, Sch Med, Sao Paulo, BrazilUniv Fed Sao Paulo, Nutr Grad, Santos, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, BrazilUniv Fed Sao Paulo, Nutr Grad, Santos, BrazilFAPESP: 2011/50289-1Web of Scienc

    Potential of hybrids among elite clones of eucalypt by microsatellite markers

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    O objetivo deste trabalho foi avaliar o potencial dos marcadores microssatélites em predizer o comportamento dos híbridos entre clones-elite de eucalipto da empresa Aracruz Celulose. Foram utilizados 21 clones-elite, cruzados conforme o esquema de dialelo balanceado. Os 137 híbridos obtidos, além dos 21 pais e 11 híbridos repetidos, foram avaliados em três locais: Aracruz, São Mateus e Caravelas, em delineamento de blocos incompletos 13x13 com 40 repetições. As parcelas foram constituídas de uma planta, espaçadas 3x3 m. Os caracteres circunferência à altura do peito (CAP) e densidade básica da madeira foram avaliados aos dois anos de idade. Os dados foram submetidos à análise dialélica e, posteriormente, foi obtida a correlação entre a divergência genética dos genitores, obtida por meio dos marcadores microssatélites, e as estimativas dos parâmetros do dialelo. A divergência genética apresentou coeficientes de correlação significativos apenas com a capacidade específica de combinação para CAP e com a média dos híbridos para CAP. A predição por meio de marcadores microssatélites possui baixa precisão para poder ser utilizada em substituição aos cruzamentos dialélicos.The objective of this work was to evaluate the potential of microsatellite markers to predict the performance of hybrids among elite clones of eucalypt from Aracruz Celulose. Twenty one elite clones were crossed in a full-diallel mating scheme. One hundred and thirty seven hybrids, 21 parents and 11 repeated hybrids were evaluated in three sites: Aracruz, São Mateus and Caravelas, in an experimental design of incomplete blocks 13x13 with 40 replicates, comprising single plant plot and spaced 3x3 m. The characters evaluated were the circumference at breast height (CBH) and the wood basic density, two years after the planting. Means were submitted to diallel analysis and, later, the correlation between the genetic divergence of parents by microsatellite markers and the estimative of diallel parameters were obtained. The genetic divergence was correlated with the specific combining ability to CBH height and with the means of hybrids to the same character. The other coefficients of correlation with the genetic divergence were not significantly different from zero. The prediction by microsatellite markers is of little accuracy to be utilized in place of diallel estimates

    Unusual intra-individual karyotypical variation and evidence of cryptic species in Amazonian populations of Pristimantis (Anura, Terrarana)

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    We report a cytogenetic analysis of three Pristimantis fenestratus frog populations of the Amazon region in Brazil. The specimens were sampled in Borba and Manaus, Amazonas State, and in Rio Branco, Acre State. They were analyzed using Giemsa, silver staining, C-banding and FISH with rDNA probes. The karyotypes of the three populations revealed 2n = 34 chromosomes, but they differed in the number and position of Ag-NORs and in the heterochromatin pattern as well. The NOR was located on the pairs 05 and 07 in the Rio Branco specimens, pair 10 in the Manaus specimens, and pair 1 in the Borba specimens. A small C-band was detected on the telomeric region of the pair 05 in the Borba population, while in the Manaus there was a heterochromatic block adjacent to the centromere of pair 9. An unusual intra-individual variation of chromosome number was observed in metaphases of Rio Branco specimens, comprising fundamental numbers of 33, 34 and 35. Additionally, interchromosome thread connections were detected between telomere - telomere, centromere - telomere and centromere - centromere regions, and among chromosomal heterochromatin-rich sites. The NOR sites were also involved in those connections. We hypothesize that this variation is due to chromosome missegregation during mitosis. The inter- and intraindividual variation in chromosome number suggests chromosomal instability in P. fenestratus, which has not been detected in any other anuran group. Since Borba is the type-locality of P. fenestratus, a taxonomic review of the Manaus and Rio Branco populations should be done, as indicated by the cytogenetic evidence that they could be new species of Pristimantis. © 2009 The Authors

    SIGNIFICADOS, INTERPRETAÇÕES E EXPECTATIVAS SOBRE A RESPONSABILIDADE SOCIAL CORPORATIVA: Uma Análise Crítica do Discurso

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    A partir do paradigma malthusiano, surge a perspectiva de que as empresas precisam assumir um papel mais amplo e responsável perante a sociedade. Assim, o estudo da responsabilidade social corporativa emerge como uma temática bastante recorrente no âmbito organizacional nas últimas décadas. O objetivo desse trabalho foi analisar as atitudes de empresários/executivos, políticos/representantes do poder público e representantes de organizações não governamentais (ONGs) no Rio de Janeiro sobre Responsabilidade Social Corporativa e explorar significados, interpretações e expectativas quanto às suas práticas. Com uma base teórica predominante de Responsabilidade Social em contraposição a outra menos ingênua, este artigo engaja-se na construção de uma análise que conclui pela necessidade de limites da ação organizacional e existência de uma pluriversalidade do conhecimento sobre desenvolvimento e administração/gestão.

    Testing a fault tolerant mixed-signal design under TID and heavy ions

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    This work presents results of three distinctradiation tests performed upon a fault tolerant data acqui-sition system comprising a design diversity redundancytechnique. The first and second experiments are Total Ion-izing Dose (TID) essays, comprising gamma and X-rayirradiations. The last experiment considers single eventeffects, in which two heavy ion irradiation campaignsare carried out. The case study system comprises threeanalog-to-digital converters and two software-based vot-ers, besides additional software and hardware resourcesused for controlling, monitoring and memory manage-ment. The applied Diversity Triple Modular Redundancy(DTMR) technique, comprises different levels of diversity(temporal and architectural). The circuit was designed ina programmable System-on-Chip (PSoC), fabricated in a130nm CMOS technology process. Results show that thetechnique may increase the lifetime of the system underTID if comparing with a non-redundant implementation.Considering the heavy ions experiments the system wasproved effective to tolerate 100% of the observed errorsoriginated in the converters, while errors in the process-ing unit present a higher criticality. Critical errors occur-ring in one of the voters were also observed. A secondheavy ion campaign was then carried out to investigatethe voters reliability, comparing the the dynamic cross sec-tion of three different software-based voter schemes im-plemented in the considered PSoC
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