RESUMO Utilizando um anticorpo monoclonal contra a aflatoxina B1 (AFB1) como ligante, foi identificado um mimotopo específico de aflatoxina B1 após se realizarem quatro ciclos de seleção biológica de 7-peptídeos aleatórios em biblioteca de fago exibida. O mimotopo é denominado P10, e sua sequência de aminoácidos é YRRHEKD. O soro imunológico de ratos Balb/c imunizados com P10 foi especificamente ligado à aflatoxina B1-albumina, indicando que o anticorpo era específico ao AFB1. Esses resultados sugerem que é possível desenvolver a vacina baseada em mimotopo associado à toxina.

Abstract This paper studies the stiffening effects of the material strain rate sensitivity and strain hardening on the saturated impulse of elastic, perfectly plastic plates. Finite element (FE) code ABAQUS is employed to simulate the elastoplastic response of square plates under rectangular pressure pulse. Rigid-plastic analyses for saturated impulse, which consider strain rate sensitivity and strain hardening, are conducted. Satisfactory agreement between the finite element models (FEM) and predictions of the rigid-plastic analysis is obtained, which verifies that the proposed rigid-plastic methods are effective to solve the problem including strain rate sensitivity and strain hardening. The quantitative results for the scale effect of the strain rate sensitivity are given. The results for the stiffening effects suggest that two general stiffening factors n 1 and n 2, which characterizes the strain rate sensitivity and strain hardening effect, respectively can be defined. The saturated displacement is inversely proportional to the stiffening factors (i.e. n 1 and n 2) and saturated impulse is inversely proportional to the square roots of the stiffening factors (i.e. n 1 and n 2). Formulae for displacement and saturated impulse are proposed based on the empirical analysis.

ABSTRACT This study was conducted to isolate Lactobacillus salivarius and Pediococcus pentosaceus strains from cecal content and investigate their probiotic potential in specific pathogen free (SPF) chickens. L. salivarius and P. pentosaceus strains were isolated from the cecal content of SPF chickens and identified by 16s rDNA sequence analysis by BLAST analysis at the National Center for Biotechnology Information and phylogenetic analysis using DNAStar software. In an in vivo experiment, 180 7-day-old SPF chickens were randomly assigned into three groups. Group 1 served as a control that was fed a basal diet without probiotic supplementation, and groups 2 and 3 were fed the basal diets supplemented with L. salivarius and P. pentosaceus at 2×108 CFU/g, respectively. Body weight (BW), average daily gain (ADG), feed conversion ratio (FCR), dressing percentage (DP), and the apparent digestibility of crude protein (AD-CP) were calculated. We also determined meat color, fat content, shear force, water content and pH value of breast and thigh muscles; ammonia, urea nitrogen and uric acid content in plasma; fecal ammonia emission level and pH value; and Lactobacillus and Escherichia coli in ceca. Compared with the control group, L. salivarius and P. pentosaceus supplementation significantly increased BW, ADG, DP, AD-CP, fat content of meat, and the number of Lactobacillus in ceca (p<0.05), and decreased FCR, plasma ammonia content, fecal ammonia emission, and pH value and the number of E. coli in ceca (p<0.05). In the in vitro experiment, L. salivarius and P. pentosaceus treatments significantly decreased the ammonia content in medium compared with the control group without probiotic treatment (p<0.05). These results suggest that P. pentosaceus and L. salivarius strains show promising probiotic properties for improving growth, meat quality and microenvironment in chickens and decreasing ammonia content in the medium.

Potassium utilization efficiency (KUE) for plants is related to genotype difference, soil characteristics, application of fertilizer and irrigation. Up to now, the KUE of different genotypes worldwide has been extensively studied, but the influence of environment stress on KUE of cotton is infrequently reported. Thus, we selected a high K utilization efficiency cotton genotype (HEG) and a low K utilization efficiency cotton genotype (LEG) as indicator plants. The results showed that both soil water stress and K stress limited the growth of cotton genotypes. The change of soil water levels had significant influence on yield, KUE, rates of fallen leaves and bolls (RF), biomass and potassium accumulation in cotton. Deficient of soil water restricted the uptake and translocation of K. The absence of soil K greatly increased the proportion of biomass of reproductive organs and K distribution to reproductive organs in this experiment. The HEG exhibited higher physiological compared with LEG under the stress conditions, especially under low K treatment.

Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.

ABSTRACT We report the case of a 45-year old woman with a painless soft tissue mass on the left side of her neck. At surgery, the lesion was solid and rubbery and revealed grey-white fibrous areas. It was pathologically confirmed as an elastofibroma, a rare, benign soft tissue tumour that is most commonly encountered in patients more than 55 years of age. Elastofibroma arising from connective tissue and usually found in the subscapular region is extremely rare in the neck. The pathogenesis of elastofibroma is still unclear but increased mechanical stress or nutritional derangement consequent to vascular involvement and hereditary factors may predispose to this lesion. Marginal excision is the treatment of choice in symptomatic patients.

RESUMEN Reportamos el caso de una mujer de 45 años con una masa de tejido suave sin dolor en el lado izquierdo del cuello. Al realizarse la cirugía, se halló que la lesión era sólida y gomosa, y presentaba áreas fibrosas de color gris-blanco. El análisis patológico confirmó que se trataba de un elastofibroma: un tumor del tejido blando, raro y benigno, que se encuentra más comúnmente en pacientes de más de 55 años de edad. Los elastofibromas que provienen del tejido conjuntivo y que generalmente se encuentran en la región subescapular, son extremadamente raros en el cuello. La patogénesis del elastofibroma no está todavía clara, pero el aumento del estrés mecánico o los desarreglos nutricionales consecuencia de problemas vasculares y factores hereditarios, pueden predisponer a esta lesión. La extirpación marginal es el tratamiento de elección en pacientes sintomáticos.

The effects of treatment with 50 and 100 mM NaCl on cotyledon growth, nitrogen assimilation, and the activities of key nitrogen metabolism enzymes were investigated in developing Jatropha curcas cotyledons. Growth inhibition was observed, and relative water content in the developing cotyledons significantly decreased in the 100 mM NaCl treatment. Lower levels of NO3-, NO2-, and NH4+ in the cotyledons were recorded when they were supplied with 50 and 100 mM NaCl. Nitrate reductase activities decline by 9.5% to 31.8% with respect to the control groups. Salt treatment also led to a marked decrease in nitrite reductase activity compared with the controls. Glutamine synthase, glutamate synthetase and dehydrogenase, alanine aminotransferase (AlaAT) and aspartate aminotransferase (AspAT) were markedly induced by the addition of NaCl. These findings will be useful for elucidating the roles key enzymes involved in nitrogen assimilation pathway of J. curcas plant.

Caixas de papelão contendo cortes de peito de frango sem pele e sem ossos, previamente acondicionadas em bandejas de polietileno expandido, com aproximadamente 200 gramas por bandeja e recobertas por filme de polietileno, foram submetidas à irradiação com 60Co, utilizando-se equipamento Nordion JS 7500. As amostras foram expostas a doses de 1,5; 3,0 e 7,0kGy, sendo irradiadas na modalidade estática a 0º e 180º em relação ao feixe de irradiação. Para avaliar a homogeneidade das doses de irradiação um conjunto de 18 dosímetros de alanina+parafina por tratamento foi colocado dentro das caixas com as amostras. Outro conjunto de dosímetros foi irradiado na faixa de 1 a 10kGy para elaboração da curva de resposta . Após a irradiação, os peitos de frango foram armazenados a 5±1ºC durante 39 dias, sendo submetidos a análises microbiológicas (contagem total de bactérias aeróbias psicrotróficas, bactérias aeróbias mesófilas, bolores e leveduras, Pseudomonas spp, enterobacteriáceas totais, bactérias lácticas e NMP de E.coli) em 10 períodos diferentes ao longo do armazenamento. Os resultados obtidos revelaram um comportamento linear dos dosímetros de alanina+parafina na faixa de 1 a 10kGy de irradiação. Com base nas avaliações microbiológicas as amostras controle tiveram vida-útil de 5 dias, observando-se um ganho na vida-útil de 1,75; 4,40 e 7,0 vezes para as amostras irradiadas com 1,5; 3,0 e 7,0kGy, respectivamente. Constatou-se uma alteração crescente do odor de queimado à medida que se aumentavam as doses de irradiação, indicando a dose de 3kGy como a mais recomendável para se garantir um produto com maior vida-útil e sem alterações sensoriais perceptíveis.

Kraft paper boxes containing 10 expanded polystyrene trays with 200g skinless deboned chicken breast each were irradiated with 60Co source of a Nordion JS7500 irradiator. The trays were previously wrapped with polyethylene film. The samples were exposed to 1.5; 3.0 and 7.0 kGy doses in the static mode at 0º and 180º in relation to the irradiation beam. Set of 18 alanine+paraffin dosimeters per treatment were distributed inside the boxes for evaluation of irradiation dose homogeneity. A separeted dose calibration curve was obtained by irradiating in the range of 1 to 10kGy. After the irradiation, the chicken breasts were stored at 5±1ºC for 39 days and were analysed microbiologically in total psychrotrophic aerobic bacteria, total mesophilic aerobic bacteria, molds and yeasts, Pseudomonas spp, Enterobacteriaceae, lactic bacteria counts and E.coli during the storage period. The results revealed a linear behaviour of the alanine+paraffin dosimeters in the range of 1 to 10kGy irradiation. In regard to the microbiological aspect, compared to the shelf-life of 5 days for the controls, there were a increasing of 1.75; 4.40 e 7.0 times shelf-life for chicken breasts irradiated with 1.5; 3.0 and 7.0kGy, respectively. There was an increasing change of the smell of burnt as the irradiation doses increased. Thus, 3kGy dose was considered as the ideal dose to assure a longer shelf-life to the product, without perceptible changes in the aspect.