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The appropriate supply of nutrients in pregnant cows has been associated with the optimal development of foetal tissues, performance of their progeny and their meat quality. The aim of this study was to evaluate supplementation effects of grazing cows in different stages of gestation on skeletal muscle development and performance of the progeny. Thereby, 27 Nellore cows were divided into three groups (n=9 for each group) and their progeny as follows: UNS, unsupplemented during gestation; MID, supplemented from 30 to 180 days of gestation; LATE, supplemented from 181 to 281 days of gestation. The percentage composition of the supplement provided for the matrices was the following: ground corn (26.25%), wheat bran (26.25%) and soya bean meal (47.5%). The supplement was formulated to contain 30% CP. Supplemented matrices received 150 kg of supplement (1 and 1.5 kg/day for cows in the MID and LATE groups, respectively). After birth, a biopsy was performed to obtain samples of skeletal muscle tissue from calves to determine number and size of muscle fibres and for messenger RNA (mRNA) expression analysis. The percentage composition of the supplement provided for the progeny was the following: ground corn grain (30%), wheat bran (30%), soya bean meal (35%) and molasses (5%). The supplement was formulated to contain 25% CP and offered in an amount of 6 g/kg BW. Performance of the progeny was monitored throughout the suckling period. Means were submitted to ANOVA and regression, and UNS, MID and LATE periods of supplementation were compared. Differences were considered at P0.10). Similarly, no differences were observed between calves for nutrient intake (P>0.10). However, greater subcutaneous fat thickness (P=0.006) was observed in the calves of LATE group. The ribeye area (P=0.077) was greater in calves born from supplemented compared with UNS cows. The supplementation of pregnant cows did not affect the muscle fibre size of their progeny (P=0.208). On the other hand, calves born from dams supplemented at mid-gestation had greater muscle fibre number (P=0.093) compared with calves from UNS group. Greater mRNA expression of peroxysome proliferator-activated receptor α (P=0.073) and fibroblast growth factor 2 (P=0.003) was observed in the calves born from MID cows. Although strategic supplementation did not affect the BW of offspring, it did cause changes in carcass traits, number of myofibres, and mRNA expression of a muscle hypertrophy and lipid oxidation markers in skeletal muscle of the offspring.

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The significance of microorganisms in root canals with regard to the aetiology of periapical infection and the need for crucial bacteria control during treatment are undeniable. In this study, we report and discuss a review of the literature on Microbiological Root Canal Sampling (MRS). The procedure is analyzed in detail, discussing its powers, limitations and the influence of sample collection procedures on the incidence of true and false positive results. Data sources: MEDLINE/PUBMED, B-On and library files of Oporto University were accessed. Selection: Papers were selected using the keywords: “root ca¬nal sampling”; “apical periodontitis”; “endodontic pathogens”; “root canal infection”; “Culture”; “molecular biology”. The references were selected under inclusion criteria such as English language, accessibility, relevance to the theme and scientific rigor. Conclusions: This review illustrated the absolute need to adhere to strict methodology procedures if valid samples are to be obtained. A combination of Culture and molecular identification approaches have confirmed the polymicrobial nature of endodontic infections with a predominance of anaerobic bacteria. Nucleic acid-based techniques provide significant additional information particularly regarding the not-yet-cultivable species of the microbial community, but greatly increase the budget of the procedure. Thus, assessment of the endodontic microflora, in the context of a polymicrobial biofilm ecosystem, and its relevance to endodontic treatments must rely in the complementariness of Culture and Metagenomics approaches as they are neither mutually exclusive nor competitive, but strongly complementary...

A importância de microrganismos em canais radiculares no que diz respeito à etiologia da infecção periapical e a necessidade de controlar bactérias durante o tratamento são incontestáveis. Neste estudo, relata-se e discute-se uma revisão da literatura sobre a amostragem microbiológica de canal radicular. O procedimento é analisado em detalhes, discutindo suas atribuições, limitações e influência de procedimentos de coleta de amostra sobre a incidência de verdadeiros e falsos resultados positivos. Fontes de dados: Foram usados MEDLINE/PubMed, B-On e arquivos da biblioteca da Universidade do Porto. Seleção: Os trabalhos foram selecionados utilizando as palavras-chave: “root canal sampling”; “apical periodontitis”; “endodontic pathogens”; “root canal infection”; “Culture”; “molecular biology”. As referências foram selecionadas de acordo com critérios de inclusão como o idioma inglês, acessibilidade, relevância para o tema e rigor científico. Conclusões: Esta revisão ilustrou a absoluta necessidade de aderir aos procedimentos metodológicos rigorosos se se pretende obter amostras válidas para análise. Uma combinação de cultura e abordagens de iden¬tificação molecular confirmaram a natureza polimicrobiana das infeções endodônticas com predominância de bactérias anaeróbias. Técnicas baseadas em ácidos nucleicos fornecem informação adicional significativa, particularmente em relação às espécies não cultiváveis da comunidade microbiana, mas aumentam muito o orçamento do procedimento. Assim, a avaliação da microflora endodôntica, no contexto de um ecossistema polimicrobiano em biofilme, e sua relevância para tratamentos endodônticos devem confiar na complementaridade entre a abordagem de cultura e de metagenômica, pois não são mutuamente exclusivas nem competitivas, mas fortemente complementares...

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A frequency scanning O-mode reflectometer was used for studies of plasma density oscillations during local Alfvén wave (LAW) excitation in the Tokamak Chauffage Alfvén Brésilien (TCABR) at the frequency f(A) = 5 MHz. It was found that the spectrum of the reflectometer output signal, which consists mainly of the "beat" frequency f(B), is modified by the LAW excitation, and two additional frequency peaks appear, which are symmetrical in relation to the LAW excitation frequency f = f(A) ± f(B). This result opens the possibility to improve the efficiency of studying the LAW induced density oscillations. The symmetry of these frequency peaks yields the possibility of finding the microwave frequency at which the reflectometer cutoff layer coincides with radial position of the LAW resonance zone in the TCABR tokamak.

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Objetivos: Demostrar la presencia de asociación entre las variaciones climáticas (variables macro y microclimáticas) con los casos de dengue en el Hospital Pérez de León (HPL) de Caracas, Venezuela, en el período 1998-2004. Materiales y métodos: Se recolectó el registro mensual de los casos confirmados de dengue del Servicio de Epidemiología del HPL. Los datos microclimáticos se obtuvieron del Servicio de Meteorología de la Fuerza Aérea Venezolana, las precipitaciones se expresaron en mm de lluvia al mes y la temperatura máxima y mínima extrema de cada mes. Se usaron como índices climáticos el NAO, SOI, ONI de acuerdo con la clasificación de la NOAA, se clasificó en años El Niño y No El Niño (neutrales y La Niña). Para encontrar las asociaciones se usaron modelos de regresión lineal. Resultados: Para el periodo estudiado se registraron un total de 2187 casos confirmados de dengue, media anual de 267,86 casos (±371,21). El 2000 fue el año con mayor número de casos (hasta 214 casos/ mes), correspondiendo climáticamente con el fenómeno de La Niña. Se observó mayor número de casos durante los años No El Niño (1999, 2000, 2001, 2004) (60,26% más que la media) en comparación con los años El Niño (1998, 2002, 2003) donde se observó disminución en comparación con la media (-67,56%) (c 2 =21,76; p<0,01). Los modelos de regresiones lineales encontraron significancia entre dengue y las anomalías en las precipitaciones de Caracas (r 2 =0,01199; F=4,635; p=0,0319) y con las temperaturas máximas de Caracas (r 2 =0,1345; F=59,37; p<0,0001). Conclusiones: Los resultados reflejan la influencia positiva que tienen las condiciones climáticas (precipitaciones, temperatura y presencia del fenómeno La Niña) sobre la epidemiología del dengue en el este de Caracas, reflejada en el ingreso de pacientes con esta enfermedad en el Hospital Pérez de León de Caracas.

Objectives: To prove the presence of an association between weather variations (macroclimatic and microclimatic) and dengue fever cases in Perez de Leon Hospital in Caracas, Venezuela, from 1998 to 2004. Materials and methods: Monthly records of confirmed dengue fever cases from the Epidemiology Service at Perez de Leon Hospital were collected. Microclimatic data were obtained from the Meteorology Service of the Venezuelan Air Force, rain was expressed as mm per month, and maximal and minimal monthly temperatures were also recorded. NAO, SOI, AND ONI were used as climate indexes, according to NOAA classification, and seasons were categorized as positive or genitive for El Niño phenomenon (the latter were classified as neutral and La Niña). Linear regression models were used for determining the associations. Results: For the period studied, 2187 confirmed cases of dengue fever were recorded, the annual mean was 267,86 cases (±371,21). The highest case toll was in 2000 (up to 214 cases per month), and this had a climatic correlation with La Niña. Years negative for El Niño had the highest number of cases (1999, 2000, 2001, 2004) (60,26% higher than the mean number of cases) compared with the years where El Niño phenomenon occurred (1998, 2002, 2003), where there was a reduction in the case number compared with the mean values (-67,56%) (x2 = 21,76; p<0,01). Linear regression models found a statistically significant association between dengue fever and rainfall abnormalities in Caracas (r 2 = 0,01199; F= 4,635; p= 0,0319), as well with maximum temperatures recorded (r 2 = 0,1345; F= 59,37; p= 0,0001). Conclusions: These results show the positive influence of climate conditions (rainfall, temperature, and La Niña phenomenon) upon dengue fever epidemiology in Eastern Caracas, which is reflected in the admission of patients with this disease in Perez de Leon Hospital in Caracas, Venezuela.

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Groups of animals (Wistar rats) were fed with rations doped with uranyl nitrate at concentrations ranging from 0.5 to 100 ppm. The uranium content in the ashes of the organs was measured by the neutron-fission track counting technique. The most striking result is that the transfer coefficients, as a function of the uranium concentration, exhibit a concave shape with a minimum around 20 ppm-U for all organs. Explanations to interpret this finding are tentatively given.

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A new and simple statistical procedure (STATFLUX) for the calculation of transfer coefficients of radionuclide transport to animals and plants is proposed. The method is based on the general multiple-compartment model, which uses a system of linear equations involving geometrical volume considerations. By using experimentally available curves of radionuclide concentrations versus time, for each animal compartment (organs), flow parameters were estimated by employing a least-squares procedure, whose consistency is tested. Some numerical results are presented in order to compare the STATFLUX transfer coefficients with those from other works and experimental data.

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