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The p66ShcA protein controls cellular responses to oxidative stress, senescence, and apoptosis. Here, we test the hypothesis that aging phenotype(s) commonly associated with the broad category of chronic kidney disease are accelerated in diabetic kidneys and linked to the p66ShcA locus. At the organ level, tissue stem cells antagonize senescent phenotypes by replacing old dysfunctional cells. Using established methods, we isolated a highly purified population of stem cell antigen-1-positive mesenchymal stem cells (Sca-1+ MSCs) from kidneys of wild-type (WT) and p66 knockout (p66 KO) mice. Cells were plated in culture medium containing normal glucose (NG) or high glucose (HG). Reactive oxygen species (ROS) metabolism was substantially increased in WT MSCs in HG medium in association with increased cell death by apoptosis and acquisition of the senescent phenotype. DNA microarray analysis detected striking differences in the expression profiles of WT and p66 KO-MSCs in HG medium. Unexpectedly, the analysis for p66 KO-MSCs revealed upregulation of Wnt genes implicated in self-renewal and differentiation. To test the in vivo consequences of constitutive p66 expression in diabetic kidneys, we crossed the Akita diabetic mouse with the p66KO mouse. Homozygous mutation at the p66 locus delays or prevents aging phenotype(s) in the kidney that may be precursors to diabetic nephropathy [ABSTRACT FROM AUTHOR]

Interleukin-7 (IL-7) is an essential T-cell survival cytokine. IL-7 receptor (IL-7Rα) deficiency severely impairs T-cell development due to substantial apoptosis. We hypothesized that IL-7Rαnull-induced apoptosis is partially contributed by an elevated p53 activity. To investigate the genetic association of IL-7/IL-7Rα signaling with the p53 pathway, we generated IL-7Rαnullp53null (DKO) mice. DKO mice exhibited a marked reduction of apoptosis in developing T cells and an augmented thymic lymphomagenesis with telomere erosions and exacerbated chromosomal anomalies, including chromosome duplications, breaks, and translocations. In particular, Robertsonian translocations, in which telocentric chromosomes fuse at the centromeric region, and a complete loss of telomeres at the fusion site occurred frequently in DKO thymic lymphomas. Cellular and molecular investigations revealed that IL-7/IL-7Rα signaling withdrawal diminished the protein synthesis of protection of telomere 1 (POT1), a subunit of telomere protective complex shelterin, leading to telomere erosion and the activation of the p53 pathway. Blockade of IL-7/IL-7Rα signaling in IL-7-dependent p53null cells reduced POT1 expression and caused telomere and chromosome abnormalities similar to those observed in DKO lymphomas. This study underscores a novel function of IL-7/IL-7Rα during T-cell development in regulating telomere integrity via POT1 expression and provides new insights into cytokine-mediated survival signals and T-cell lymphomagenesis. [ABSTRACT FROM AUTHOR]

Ten barrows of 35 kg of weight were used to study the rectal digestibility of five diets containing different ratios of sugarcane high-test and final molasses (75:0, 60:15, 45:30, 30:45 and 15:60 respectively). The diets were supplemented with fishmeal and Saccharomyces yeast as protein source, and daily feed intake was ad libitum. Rectal digestibility of DM, N, and energy were 91.2, 84.4 and 85.7; 90.5, 84.1 and 90.7; 89.8, 83.2 and 89.1; 88.8, 84.2 and 90.0 and 87.8, 92. 8 and 88.3 % in the same order. Significant differences (P < 0.05) among diets were found for energy digestibility, although DM, organic matter, and N digestibility tended to decrease with increasing levels of final molasses in the diet. A linear response was found in feed consumption (R², 0. 837; P < 0.029), which was highest and lowest for diets containing high-test and final molasses (2.4 and 1.9 kg DM/animal, respectively). According to the results, it is not possible to consider that rectal digestibility of nutrients in the diets are directly responsible per se for performance traits determined by a high proportion of final molasses in the feed. Other causes, such as the low energy density of final sugar molasses, should be directly involved in this status, which could be aggravated if animals do not increase their voluntary feed intake. [ABSTRACT FROM AUTHOR]

Se usaron diez cerdos machos castrados de 35 kg para estudiar la digestibilidad rectal de cinco dietas que contenían diferentes proporciones de miel rica y miel final de caña de azúcar (75:0, 60:15, 45:30, 30:45 y 15:60, respectivamente). Las dietas se suplementaron con harina de pescado y levadura torula como fuentes de proteína. El consumo de alimento fue ad libitum. La digestibilidad rectal de MS, N y energía fueron 91.2, 84.4 y 85.7; 90.5, 84.1 y 90.7; 89.8, 83.2 y 89.1; 88.8, 84.2 y 90.0 y 87.8, 92. 8 y 88.3 % en ese mismo orden. Se encontraron diferencias significativas (P < 0.05) entre dietas para la digestibilidad de la energía, aunque la digestibilidad de MS, materia orgánica y N tendieron a decrecer con niveles crecientes de miel final en la comida. Se halló una respuesta lineal en el consumo de alimento (R², 0. 837; P < 0.029), que fue el más alto y el más bajo con dietas conteniendo miel rica o miel final (2.4 y 1.9 kg MS por animal, respectivamente). De acuerdo con los resultados de la presente investigación, no es posible considerar que la digestibilidad rectal de nutrientes per se de la dieta es la responsable directa de los rasgos de comportamiento determinados por la alta proporción de miel final en el alimento. Otras causas, tales como la baja densidad energética de la miel final, estarían directamente involucradas en este status, que pudiera agravarse si los animales no incrementan su consumo voluntario de alimento. [ABSTRACT FROM AUTHOR]

The foliate consumption per day of the most abundant species of the chrysomelidae complex present in soybean was determined under laboratory conditions. The attack repercussion of these insects on growth and productivity indicators (plant height, number of trifoliate leaves and vegetables per plant, foliate dry and fresh weight of vegetables and the total of the plant) of the varieties Cubasoy-23, Incasoy-24 and Incasoy-27 was studied in mesh houses. Also, absolute growth and relative rate, foliage and specific area and harmfulness coefficient for the grain weight were determined. Maecolaspis brunnea was the species consuming more foliate per day (21.33 cm²). Damages caused by the chrysomelidae complex significantly affected growth and development indicators, as well as yield components in spite of crop recovery capacity. Under greenhouse conditions, the variety CS 23 showed the most unfavourable behaviour to the attack of these insects. [ABSTRACT FROM AUTHOR]

The article discusses research which evaluated the anti-nutritional factor contents of four sorghum grain varieties cultivated in Cuba. The study showed that the sorghum varieties contain amounts of non-starch polysaccharides and did not negatively affect the biological and productive performance. The results confirm that the contents of non-starch polysaccharides in the varieties do not vary.

Soil samplings were carried out in three localities in Matanzas province to determine the fauna of burrowing bugs associated to plants of economical interest. The species were identified using dicotomic keys and by male genitalia studies. Six burrowing bug species belonging to the genera Dallasiellus Berg, Amnestus Dallas, Cyrtomenus Amyot and Tominotus Mulsant were found. A Dallasiellus new species for science is reported which together with Dallasiellus scitus (Walk.) were the most frequent species. Cynodon dactylon L., Ficus elastica Roxb, Scindapsus aureus Engl, Guaiacum sanctum Lim and Manihot esculenta Crantz were new host reports for the Cydnidae fauna. [ABSTRACT FROM AUTHOR]

The damage caused by the stink bug complex Piezodorus guildinii (West.), Nezara viridula (L.), Euschistus biffibulus (Pal de Beauv) and Acrosternun sp. (Heteroptera: Pentatomidae) on soybean fruits and grains was characterized by the first time using histological techniques. The insect punctures on fruits produced necrotic points in the epicarpio. The style reached the seed and broke the macroesclereida layer, which provoked the formation of tilides near the damaged cells. Small, deformed and necrotic grains were formed as a result of the pest attack. In addition, seed death and pathogen infection were detected. [ABSTRACT FROM AUTHOR]

Vanesa cardui Poey (Lepidoptera: Nymphalidae) is reported in soybean crop for the first time in Cuba. Larvae were detected feeding on Cubasoy-23 foliage variety in farms located at the National Institute of Agricultural Science, Havana province. Field observations on the caterpillar attack and foliage damages were made. Larvae were reared up to adults in order to identify butterflies. Larvae, pupae and adult description and possible causes determining infestation are discussed. In our country, there is not any report mentioning caterpillar attack on soybean. For this reason, it should be considered as a new record to be included in the harmful insect list in the crop. [ABSTRACT FROM AUTHOR]

La2Mo2-yByO9-δ (B=Cr and Nb) series have been prepared as nanocrystalline materials from a freeze-drying precursor method. The structural characterisation and stabilisation of the high temperature β-polymorph were investigated by high resolution X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The overall conductivity was studied by impedance spectroscopy in the temperature range of 200-800ºC. Nb has a solubility limit of y less than 0.1 in La2Mo2O9, stabilising the β-polymorph at room temperature. On the other hand, Mo can be partially substituted by Cr up to y=1 and it also stabilises the β-polymorph. These substitutions do not improve the ionic conductivity compared to non-substituted La2Mo2O9. Only the sample with highest Cr-content showed a significant enhancement of the overall conductivity, which seems to be explained by an increase of the electronic contribution due to Cr reduction.La serie de compuestos La2Mo2-yByO9-δ (B=Cr and Nb) ha sido preparada en forma de materiales nanocristalinos a partir de un método de precursores liofilizados. La caracterización estructural y estabilización del polimorfo-β de alta temperatura fueron investigadas por difracción de rayos-X de alta resolución (XRD) y calorimetría diferencial de barrido (DSC). La conductividad total fue estudiada por espectroscopía de impedancia en el rango de temperaturas de 200-800ºC. El Nb tiene una solubilidad límite de solo y=0.1 en La2Mo2O9 y estabiliza el polimorfo-β a temperatura ambiente. Por otra lado, el Mo puede ser parcialmente substituido por Cr hasta y=1 estabilizando también el polimorfo-β. Estas sustituciones no mejoran la conductividad iónica de la fase original La2Mo2O9. Únicamente la muestra con mayor contenido en Cr mostró un aumento significativo de la conductividad, el cual parece ser explicado por un incremento de la contribución electrónica debido a la reducción del Cr.