Localization of ribosomal genes in three Pimelodus species (Siluriformes, Pimelodidae) of the São Francisco River: 5S genes as species markers and conservation of the 18S rDNA sites

Pimelodidae is one of the most representative of Neotropical catfish families. However, these fish are still poorly studied in terms of cytogenetics, especially regarding the application of more accurate techniques such as the chromosomal localization of ribosomal genes. In the present work, fluorescent in situ hybridization with 5S and 18S rDNA probes was employed for rDNA site mapping in Pimelodus sp., P. fur and P. maculatus from the São Francisco River in the Três Marias municipality - MG. The results from the application of the 18S probe confirmed the previous data obtained by silver nitrate staining, identifying a simple nucleolar organizing region system for these species. However, the labeling results from the 5S rDNA probe demonstrated a difference in the number and localization of these sites between the analyzed species. The obtained data allowed inferences on the possible processes involved in the karyotypic evolution of this genus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Membrane interactions of S100A12 (Calgranulin C)

S100A12 (Calgranulin C) is a small acidic calcium-binding peripheral membrane protein with two EF-hand structural motifs. It is expressed in macrophages and lymphocytes and highly up-regulated in several human inflammatory diseases. In pigs, S100A12 is abundant in the cytosol of granulocytes, where it is believed to be involved in signal modulation of inflammatory process. In this study, we investigated the interaction of the porcine S100A12 with phospholipid bilayers and the effect that ions (Ca2+, Zn2+ or both together) have in modifying protein-lipid interactions. More specifically, we intended to address issues such as: (1) is the protein-membrane interaction modulated by the presence of ions? (2) is the protein overall structure affected by the presence of the ions and membrane models simultaneously? (3) what are the specific conformational changes taking place when ions and membranes are both present? (4) does the protein have any kind of molecular preferences for a specific lipid component? To provide insight into membrane interactions and answer those questions, synchrotron radiation circular dichroism spectroscopy, fluorescence spectroscopy, and surface plasmon resonance were used. The use of these combined techniques demonstrated that this protein was capable of interacting both with lipids and with ions in solution, and enabled examination of changes that occur at different levels of structure organization. The presence of both Ca2+ and Zn2+ ions modify the binding, conformation and thermal stability of the protein in the presence of lipids. Hence, these studies examining molecular interactions of porcine S100A12 in solution complement the previously determined crystal structure information on this family of proteins, enhancing our understanding of its dynamics of interaction with membranes

Fat deposition of parotid glands

AbstractParotid gland parenchyma histology may be altered by local or systemic, pathological or non-pathological conditions.ObjectiveThis paper aims to highlight the fatty degeneration of the parotid gland, a not well-known non-pathological condition.MethodIn a retrospective study, we collected a series of 6 patients which presented a swelling of the parotid, but even after extensive research, a diagnosis was not reached.ResultsThrough the retrospective analysis of records we found fatty degeneration of the parotid in an MRI scan of all patients.ConclusionThis condition, despite being physiological and expected with aging, may be related to clinical and radiological swelling of these glands

Major Meta-Analysis, Randomized Clinical Studies, and International Consensus on Serum Levels and Importance of Supplementing Vitamin D: State of the art

Introduction: Hypovitaminosis D is highly prevalent and constitutes a public health problem worldwide. It can affect more than 90% of individuals, depending on the population studied. Objective: To make a broad analysis of the world literature to compose the State of the Art on serum vitamin D levels and its adequate supplementation, to prevent and mitigate various diseases, based on randomized clinical studies, analysis, and latest international conferences and consensus. Methods: The present study followed a literary review of randomized clinical studies, meta-analysis, and the latest international consensus. Cochrane instrument was adopted to assess the quality of the included studies between 2015 and 2020. Major considerations and conclusion: Laboratory evaluation should be performed by measuring 25(OH)D, and the main groups of individuals at risk for vitamin D deficiency are the elderly, patients with osteoporosis, history of falls and fractures, obese, pregnant women, and infants. For patients with osteoporosis and increased risk of fractures, recommended that concentrations of 25(OH)D remain above 30 ng/mL for full benefits on the prevention of secondary hyperparathyroidism, decreased risk of falls. Special considerations must have taken to pregnant women and infants, in patients with chronic renal failure, obese patients, and those undergoing bariatric surgery. Several clinical studies and current meta-analysis have shown significant results with vitamin D supplementation in cardiovascular complications, diabetes, cancer, autoimmune diseases, cognitive function, among others, with doses above 30 ng/mL, reaching up to 70 ng/mL, and maintaining serum dosage at 50 ng/mL

Efeitos da globalização sobre a cultura do milho no Brasil.

A globalizacao, ao permitir um fluxo mais livre de bens e servicos, afeta o mercado onde existem condicoes favoraveis para a movimentacao e modificacao dos bens e servicos. No Brasil, ela afetou a producao de milho ao modificar as condicoes da comercializacao tanto de grao, favorecendo importacoes do Paraguai e da Argentina, como de produtos derivados de sua transformacao (principalmente a exportacao de carne de aves). A alteracao mais dramatica ocorreu no fornecimento dos insumos utilizados na producao. Como resultado das aquisicoes verificadas nos ultimos anos, uma unica empresa multinacional domina 63% do mercado de sementes de milho. Tres outras multinacionais dominam outros 22%. A concorrencia neste mercado ocorre no campo tecnologico, quando reflete o dinamismo dos programas de pesquisa, porem cria condicoes para o direcionamento tecnologico, segundo o interesse de empresas lideres. Outro componente da concorrencia verifica-se no campo financeiro, onde os maiores problemas tem ocorrido para as empresas de capital nacional. Considerando-se o papel estrategico deste segmento da cadeia produtiva do milho, medidas de apoio para pequenas e medias empresas produtivas de sementes e o fortalecimento de atividade de pesquisa publica e privada contribuirao para manter o progresso tecnologico e a competicao no setor

Um sistema de dinâmica demográfica para os municípios amazônicos

Population growth and migration represent an important underlying cause of deforestation in the Brazilian Amazon. Models designed to simulate deforestation should therefore incorporate a demographic dynamics system to help project the influence of these variables on the location and rates of deforestation across the basin. We present a demographic model that projects population at municipality level by computing migration fluxes among the Amazonian municipalities and in and outward the region, as well as their crude birth and death rates. The annual projections from 1995 to 2035 are based mainly on mortality, fertility and migration data from 1991’s and 2000’s IBGE census. The model assumes a logistic curve to project the municipalities’ crude birth and death rates, which are derived using specific functions of fertility and mortality by age. The migratory fluxes were determined by establishing a origin-destiny matrix for all the Amazonian municipalities and Brazilian states for the 1995-2000 time period. VESIM, a system-thinking software which allows the solution of simultaneous equation for the 810 defined spatial units by employing integration techniques - such as the Runge-Kutta method, is used to implement the simulation model. Validation was performed comparing 2000’s IBGE municipality data. The model is designed to handle various scenarios of regional migration in face of the current projects to expand infrastructure across the Amazon region.demographic model; regional migration; Brazilian Amazon

Análise de curto-circuito em sistemas desequilibrados de distribuição com geração distribuída

No presente trabalho, realiza-se uma análise numérica de faltas em sistemas de distribuição desequilibrados com geração distribuída. Na metodologia proposta, o cálculo das correntes de curto-circuito utiliza uma versão trifásica da matriz impedância de barra em componentes de fase. Na obtenção dessa matriz, é utilizado o método de construção direta, implementado no ambiente computacional MATLAB®. Para avaliar os resultados da metodologia, o sistema teste IEEE 13 barras modificado foi modelado e simulado, sendo realizada a análise de curto-circuito considerando o aumento gradual do nível de penetração da geração distribuída, permitindo assim analisar o impacto dos geradores no nível de curto-circuito do sistema elétrico.In the present work, a numerical analysis of faults in unbalanced distribution systems with distributed generation is carried out. In the proposed methodology, the calculation of short-circuit currents uses a three-phase version of the bus-impedance matrix in phase components. In order to obtain this matrix, the direct construction method was implemented in the MATLAB® computational environment. In order to evaluate the results of the methodology, the modified IEEE 13 nodes test feeder was modeled and simulated, considering the gradual increase of distributed generation penetration, thus allowing to analyze the impact of distributed generation on the short-circuit level of the electric system