474 research outputs found
Genomic selection in rubber tree breeding: A comparison of models and methods for managing G×E interactions
Several genomic prediction models combining genotype × environment (G×E) interactions have recently been developed and used for genomic selection (GS) in plant breeding programs. G×E interactions reduce selection accuracy and limit genetic gains in plant breeding. Two data sets were used to compare the prediction abilities of multienvironment G×E genomic models and two kernel methods. Specifically, a linear kernel, or GB (genomic best linear unbiased predictor [GBLUP]), and a nonlinear kernel, or Gaussian kernel (GK), were used to compare the prediction accuracies (PAs) of four genomic prediction models: 1) a single-environment, main genotypic effect model (SM); 2) a multienvironment, main genotypic effect model (MM); 3) a multienvironment, single-variance G×E deviation model (MDs); and 4) a multienvironment, environment-specific variance G×E deviation model (MDe). We evaluated the utility of genomic selection (GS) for 435 individual rubber trees at two sites and genotyped the individuals via genotyping-by-sequencing (GBS) of single-nucleotide polymorphisms (SNPs). Prediction models were used to estimate stem circumference (SC) during the first 4 years of tree development in conjunction with a broad-sense heritability (H2) of 0.60. Applying the model (SM, MM, MDs, and MDe) and kernel method (GB and GK) combinations to the rubber tree data revealed that the multienvironment models were superior to the single-environment genomic models, regardless of the kernel (GB or GK) used, suggesting that introducing interactions between markers and environmental conditions increases the proportion of variance explained by the model and, more importantly, the PA. Compared with the classic breeding method (CBM), methods in which GS is incorporated resulted in a 5-fold increase in response to selection for SC with multienvironment GS (MM, MDe, or MDs). Furthermore, GS resulted in a more balanced selection response for SC and contributed to a reduction in selection time when used in conjunction with traditional genetic breeding programs. Given the rapid advances in genotyping methods and their declining costs and given the overall costs of large-scale progeny testing and shortened breeding cycles, we expect GS to be implemented in rubber tree breeding programs
Avaliação da depleção linfóide folicular da Bursa de Fabricius: uma metodologia alternativa utilizando análise digital de imagem e redes neurais artificiais
Fifty Bursa of Fabricius (BF) were examined by conventional optical microscopy and digital images were acquired and processed using Matlab® 6.5 software. The Artificial Neuronal Network (ANN) was generated using Neuroshell® Classifier software and the optical and digital data were compared. The ANN was able to make a comparable classification of digital and optical scores. The use of ANN was able to classify correctly the majority of the follicles, reaching sensibility and specificity of 89% and 96%, respectively. When the follicles were scored and grouped in a binary fashion the sensibility increased to 90% and obtained the maximum value for the specificity of 92%. These results demonstrate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion. In addition it provides objective results that allow measuring the dimension of the error in the diagnosis and classification therefore making comparison between databases feasible.Cinquenta Bursa de Fabrícius (BF) foram examinadas através de microscopia óptica convencional e imagens digitais foram obtidas e processadas através do software Matlab® 6.5. Redes Neurais Artificiais (ANN) foram geradas com a utilização do software Neuroshell® Classifier, e os dados das análises óptica e digital foram comparados. A ANN classificou corretamente a maioria dos folículos, atingindo sensibilidade e especificidade de 89% e 96%, respectivamente. Quando os folículos foram agrupados de forma binária houve um aumento da sensibilidade para 90% e obteve-se um valor máximo para a especificidade de 92%. Estes resultados demonstram que o uso da análise digital de imagem associada à ANNé uma ferramenta bastante útil para a classificação patológica da depleção linfóide da BF. Além disso, fornece resultados objetivos que permitem medir a dimensão do erro classificatório, tornando possível a comparação entre distintos bancos de dados
Acute exercise induce endothelial nitric oxide synthase phosphorylation via Akt and AMP-activated protein kinase in aorta of rats: Role of reactive oxygen species
AbstractBackgroundAcute exercise increases reactive oxygen species (ROS) levels, including hydrogen peroxide (H2O2). H2O2 promotes endothelial nitric oxide synthase (eNOS) activation and phosphorylation in endothelial cells. With this in mind, the present study was designed to evaluate ex vivo eNOS phosphorylation in rat aortas incubated with H2O2 and to test this hypothesis in vivo in the aortas of rats submitted to acute exercise.MethodsFor ex vivo studies, six groups of aortic tissue were formed: control, H2O2, N-acetylcysteine (NAC), LY294002, compound C, and LY294002 plus compound C. While incubation with H2O2 increased Akt, AMPK and eNOS phosphorylation, pre-incubation with NAC strongly reduced the phosphorylation of these enzymes. For in vivo studies, male Wistar rats were divided into four groups: control, cont+NAC, exercise, and exer+NAC. After a 3h swimming session, animals were decapitated and aortas were excised for biochemical and immunoblotting analysis.ResultsAcute exercise increased superoxide levels and dichlorofluorescein (DCF) concentrations, and this increase was related to phosphorylation of Akt, AMPK and eNOS. On the other hand, use of NAC reduced superoxide levels and DCF concentration. Reduced superoxide levels and DCF in the exer+NAC group were associated with decreased Akt, AMPK and eNOS phosphorylation. These results appear to be connected with vascular function because VASP phosphorylation increased in acute exercise and decreased in exer+NAC.ConclusionOur results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK
Hipomagnesemia secundária ao uso crônico de Inibidores de Bomba de Prótons: Relato de Caso
Modelo do Estudo: Relato de Caso. Objetivos: Apresentar um caso de hipomagnesemia sintomática associada a hipocalcemia induzido pelo uso de Omeprazol por cerca de 6 anos, com respectiva revisão de literatura. Métodos: Estudo dos achados clínicos e laboratoriais, associado à discussão da origem multifatorial do problema em questão. Relato de Caso: Paciente apresentou, há 2 meses, um episódio de convulsão e tremores, e outra convulsão à admissão, além de outros sinais clínicos de deficiência de magnésio, como parestesias, tremores e cãibras. Exames sanguíneos de acompanhamento de internação revelaram baixos valores séricos de cálcio (8,0 mg/dL) e magnésio (0,94 mg/dL), e níveis de sódio, potássio, uréia, creatinina e vitamina D dentro da normalidade. Dentre os medicamentos dos quais fazia uso, o Omeprazol era utilizado em regime de cronicidade, estando presente à admissão e nos 6 anos anteriores. A reposição de magnésio resultou em aumento parcial da concentração sérica (1,30 mg/dL) e melhora parcial da sintomatologia apresentada. Após a retirada do Omeprazol, os valores séricos de magnésio voltaram ao padrão de normalidade (2,50 mg/dL), ocorrendo remissão total dos sintomas. Importância: A Hipomagnesemia induzida pelo uso crônico de inibidores da bomba de prótons (IBP) é uma condição que pode levar a consequências clínicas graves, e tal situação pode ser revertida pela simples suspensão da medicação, medida capaz de restaurar o equilíbrio homeostático do magnésio.Design of the study: Case report. Objectives: To present, through a case report, a framework of symptomatic hypomagnesaemia associated with hypocalcemia induced by the use of Omeprazole for a long period of time. Methods: Study of clinical and laboratory findings associated with the discussion of the multifactorial origin of the problem in question. Results: The patient depicted in this study showed clinical signs of magnesium depletion or deficiency, evidenced by seizures, tremors, cramps and paresthesias. Blood tests for monitoring of admission revealed low levels of calcium (8,0 mg/dL) and magnesium (0,94 mg/dL), with values of sodium, potassium, urea, creatinine and vitamin D within normal limits. The patient was using Omeprazole at admission. After the withdrawal of Omeprazole, serum magnesium returned to normal range and clinical ceased. Relevance: Hypomagnesaemia is a clinical condition of difficult to diagnose and rarely appears as a differential diagnosis. Chronic administration of proton pump inhibitors represents one of the possible genesis of this change of magnesium and should be considered as a potential cause of harm and should be promptly identified and treated with the suspension of the inhibitor
Giardia lamblia and respiratory allergies: a study of children from an urban area with a high incidence of protozoan infections
OBJECTIVES: There is a high incidence of intestinal parasite infection in urban areas in the Northeast of Brazil. Giardia lamblia infections have been associated with increased prevalence of cutaneous allergies and gastrointestinal disorders. However, little is known about the relationship between giardiasis and allergic diseases of the airways. The present study aimed to investigate the possible association between respiratory allergic diseases and infections by G. lamblia in children from urban areas. METHODS: This study recruited 110 patients of both sexes aged 5-15 years. Patients were administered a questionnaire evaluating clinical symptoms and were given skin tests, parasite tests and serum tests. RESULTS: A high incidence of G. lamblia was observed (45%, 50/110). Infections by this protozoan were not associated with increased risk of respiratory allergy (p = 0.075), high total IgE levels (p = 0.701), positive specific IgE tests (p = 0.250), or positive skin tests for a range of environmental allergens (p = 0.239). CONCLUSION: This study demonstrated that symptoms of asthma, skin allergy and serum markers were not associated with G. lamblia infections in this sample of children from urban areas.OBJETIVO: Uma elevada incidência de enteroparasitoses é encontrada em regiões urbanas do nordeste brasileiro. As infecções por Giardia lamblia têm sido relacionadas com aumento da prevalência de alergias cutâneas e gastrointestinais. Contudo, ainda existe pouca informação sobre a associação entre a giardíase e doenças alérgicas das vias aéreas. Diante disso, o presente estudo se propôs a verificar a relação entre a infecção por G. lamblia em crianças de área urbana e reatividade alérgica respiratória. MÉTODOS: O estudo incluiu 110 pacientes, de ambos os sexos e idades, entre 5 e 15 anos. Os pacientes foram submetidos a questionários de avaliação dos sintomas clínicos, testes cutâneos de leitura imediata e exames coproparasitológicos e sorológicos. RESULTADOS: Foi verificada uma frequência elevada de crianças infectadas por G. lamblia (45%, 50/110). A infecção pelo protozoário não foi associada com maior risco de alergias respiratórias (p = 0,075), elevação de IgE total (p = 0,701), IgE específica (p = 0,250) ou teste cutâneo positivo para diferentes alérgenos ambientais (p = 0,239). CONCLUSÃO: O estudo demonstrou que a presença dos sintomas de asma, atopia cutânea e marcadores sorológicos não foram associados com a presença de infecção pela G. lamblia nessa amostra de crianças.Ministério da Saúde (Governo Federal do Brasil)Ministério da Ciência e e Tecnologia (Governo Federal do Brasil)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de Pernambuco Laboratório de Imunopatologia Keizo AsamiUFPE Laboratório de Imunopatologia Keizo AsamiUFPE Hospital das Cínicas ImunologiaUFPE Hospital das Clínicas ImunologiaUFPE Hospital das ClínicasUniversidade Federal de São Paulo (UNIFESP) Pediatria e Ciências AplicadasUNIFESP Imunologia Clínica e Reumatologia Pediatria e Ciências Aplicadas PediatriaUFPEUFPE Programa de Pós-graduação em Ciências da SaúdeUNIFESP, Pediatria e Ciências AplicadasUNIFESP, Imunologia Clínica e Reumatologia Pediatria e Ciências Aplicadas PediatriaCNPq: 402666/2005-4SciEL
An Intracellular Arrangement of Histoplasma capsulatum Yeast-Aggregates Generates Nuclear Damage to the Cultured Murine Alveolar Macrophages
Histoplasma capsulatum is responsible for a human systemic mycosis that primarily affects lung tissue. Macrophages are the major effector cells in humans that respond to the fungus, and the development of respiratory disease depends on the ability of Histoplasma yeast cells to survive and replicate within alveolar macrophages. Therefore, the interaction between macrophages and H. capsulatum is a decisive step in the yeast dissemination into host tissues. Although the role played by components of cell-mediated immunity in the host's defense system and the mechanisms used by the pathogen to evade the host immune response are well understood, knowledge regarding the effects induced by H. capsulatum in host cells at the nuclear level is limited. According to the present findings, H. capsulatum yeast cells display a unique architectural arrangement during the intracellular infection of cultured murine alveolar macrophages, characterized as a formation of aggregates that seem to surround the host cell nucleus, resembling a crown. This extranuclear organization of yeast-aggregates generates damage on the nucleus of the host cell, producing DNA fragmentation and inducing apoptosis, even though the yeast cells are not located inside the nucleus and do not trigger changes in nuclear proteins. The current study highlights a singular intracellular arrangement of H. capsulatum yeast near to the nucleus of infected murine alveolar macrophages that may contribute to the yeast’s persistence under intracellular conditions, since this fungal pathogen may display different strategies to prevent elimination by the host's phagocytic mechanisms
Study of monthly precipitation during the rainy season in Diamantina, Minas Gerais
O objetivo deste trabalho foi estudar o comportamento da precipita??o pluvial no per?odo da esta??o chuvosa na regi?o de Diamantina, MG. Dados de precipita??o pluviom?trica mensal, da s?rie hist?rica de 1977 a 2006, foram utilizados e averiguada a probabilidade para v?rias classes de precipita??o, atrav?s da fun??o de frequ?ncia acumulada, usando-se a metodologia da distribui??o Weibull com averigua??o de ader?ncia pelo teste Kolmogorov-Smirnov com n?vel de signific?ncia de 5%; de classes definidas em fun??o de percentis predeterminados. Os resultados mostram que a esta??o chuvosa, compreendida entre outubro e mar?o, representa 88% do total precipitado anual. Os meses de janeiro e dezembro apontam as maiores probabilidades de ocorr?ncia de precipita??o com 220,1 mm e 167,8 mm, respectivamente, a n?vel de 25% de probabilidade de ocorr?ncia. O modelo de distribui??o Weibull apresentou bom ajuste da s?rie climatol?gica para estudos probabil?sticos mostrando os par?metros dentro dos limites estat?sticos preestabelecidos.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)This paper had as its objective the study of the rainfall behavior in the rainy season in the area of Diamantina, MG, Brazil. Monthly rainfall data of historical series from 1977 to 2006 were used. The probability was checked of several rainfall classes through the accumulated frequency function using the Weilbull's distribution methodology with adherence verification by Kolmogorov-Smirnov test with significance level of 5%, classes defined by predetermined percentage. The results show that the rainy season, between October and March, represents 88% of the annual rainfall. The months of January and December presented the largest probabilities of rainfall with 220.1 mm and 167.8 mm, respectively, at a level of 25% of occurrence probability. The Weilbull distribution model presented a good adjustment of the climatic series for probabilities studies, showing the parameters within the statistical limits established before
Ages and metallicities of stellar clusters using S-PLUS narrow-band integrated photometry: the Small Magellanic Cloud
The Magellanic Clouds are the most massive and closest satellite galaxies of
the Milky Way, with stars covering ages from a few Myr up to 13 Gyr. This makes
them important for validating integrated light methods to study stellar
populations and star-formation processes, which can be applied to more distant
galaxies. We characterized a set of stellar clusters in the Small Magellanic
Cloud (SMC), using the .
This is the first age (metallicity) determination for 11 (65) clusters of this
sample. Through its 7 narrow bands, centered on important spectral features,
and 5 broad bands, we can retrieve detailed information about stellar
populations. We obtained ages and metallicities for all stellar clusters using
the Bayesian spectral energy distribution fitting code .
With a sample of clusters in the color range , for which
our determined parameters are most reliable, we modeled the age-metallicity
relation of SMC. At any given age, the metallicities of SMC clusters are lower
than those of both the Gaia Sausage-Enceladus disrupted dwarf galaxy and the
Milky Way. In comparison with literature values, differences are
log(age) and [Fe/H], which is
comparable to low-resolution spectroscopy of individual stars. Finally, we
confirm a previously known gradient, with younger clusters in the center and
older ones preferentially located in the outermost regions. On the other hand,
we found no evidence of a significant metallicity gradient.Comment: 12 pages, 11 figure
Apreciação dos estudantes das atividades experimentais desenvolvidas pelo PIBID – Química em aulas do 2º ano Ensino Médio de uma Escola Pública do município de Diamantina – MG
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BUSCANDO ENTENDER A PREPARAÇÃO DESPORTIVA A LONGO PRAZO A PARTIR DAS CAPACIDADES FÍSICAS EM CRIANÇAS
Atualmente no âmbito do Treinamento Desportivo, uma das preocupações direciona-se ao entendimento do processo de preparação a longo prazo para que se possa formar indivíduos capazes de realizar ou mesmo suportar as exigências que determinado desporto solicita. Nesse sentido o entendimento de que o processo de organização envolve diversos aspectos em diferentes âmbitos, pretende-se aqui discutir três aspectos: I) conhecimento das diferentes indicações de estruturação desportiva, II) entendimento das particularidades do organismo nesta faixa etária e, por fim, III) direcionamento do treinamento das diferentes capacidades físicas
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