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Angiotensin II (Ang II) is a critical regulator of insulin signaling in the cardiovascular system and metabolic tissues. However, in adipose cells, the regulatory role of Ang II on insulin actions remains to be elucidated. The effect of Ang II on insulin-induced insulin receptor (IR) phosphorylation, Akt activation, and glucose uptake was examined in 3T3-L1 adipocytes. In these cells, Ang II specifically inhibited insulin-stimulated IR and insulin receptor substrate-1 (IRS-1) tyrosine-phosphorylation, Akt activation, and glucose uptake in a time-dependent manner. These inhibitory actions were associated with increased phosphorylation of the IR at serine residues. Interestingly, Ang II-induced serine-phosphorylation of IRS was not detected, suggesting that Ang II-induced desensitization begins from IR regulation itself. PKC inhibition by BIM I restored the inhibitory effect of Ang II on insulin actions. We also found that Ang II promoted activation of several PKC isoforms, including PKCα/ßI/ßII/δ, and its association with the IR, particularly PKCßII, showed the highest interaction. Finally, we also found a similar regulatory effect of Ang II in isolated adipocytes, where insulin-induced Akt phosphorylation was inhibited by Ang II, an effect that was prevented by PKC inhibitors. These results suggest that Ang II may lead to insulin resistance through PKC activation in adipocytes.

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In the present study, we determined the cellular regulators of ERK1/2 and Akt signaling pathways in response to human CRF1 receptor (CRF1R) activation in transfected COS-7 cells. We found that Pertussis Toxin (PTX) treatment or sequestering Gßγ reduced CRF1R-mediated activation of ERK1/2, suggesting the involvement of a Gi-linked cascade. Neither Gs/PKA nor Gq/PKC were associated with ERK1/2 activation. Besides, CRF induced EGF receptor (EGFR) phosphorylation at Tyr1068, and selective inhibition of EGFR kinase activity by AG1478 strongly inhibited the CRF1R-mediated phosphorylation of ERK1/2, indicating the participation of EGFR transactivation. Furthermore, CRF-induced ERK1/2 phosphorylation was not altered by pretreatment with batimastat, GM6001, or an HB-EGF antibody indicating that metalloproteinase processing of HB-EGF ligands is not required for the CRF-mediated EGFR transactivation. We also observed that CRF induced Src and PYK2 phosphorylation in a Gßγ-dependent manner. Additionally, using the specific Src kinase inhibitor PP2 and the dominant-negative-SrcYF-KM, it was revealed that CRF-stimulated ERK1/2 phosphorylation depends on Src activation. PP2 also blocked the effect of CRF on Src and EGFR (Tyr845) phosphorylation, further demonstrating the centrality of Src. We identified the formation of a protein complex consisting of CRF1R, Src, and EGFR facilitates EGFR transactivation and CRF1R-mediated signaling. CRF stimulated Akt phosphorylation, which was dependent on Gi/ßγ subunits, and Src activation, however, was only slightly dependent on EGFR transactivation. Moreover, PI3K inhibitors were able to inhibit not only the CRF-induced phosphorylation of Akt, as expected, but also ERK1/2 activation by CRF suggesting a PI3K dependency in the CRF1R ERK signaling. Finally, CRF-stimulated ERK1/2 activation was similar in the wild-type CRF1R and the phosphorylation-deficient CRF1R-Δ386 mutant, which has impaired agonist-dependent ß-arrestin-2 recruitment; however, this situation may have resulted from the low ß-arrestin expression in the COS-7 cells. When ß-arrestin-2 was overexpressed in COS-7 cells, CRF-stimulated ERK1/2 phosphorylation was markedly upregulated. These findings indicate that on the base of a constitutive CRF1R/EGFR interaction, the Gi/ßγ subunits upstream activation of Src, PYK2, PI3K, and transactivation of the EGFR are required for CRF1R signaling via the ERK1/2-MAP kinase pathway. In contrast, Akt activation via CRF1R is mediated by the Src/PI3K pathway with little contribution of EGFR transactivation.

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Hexavalent chromium (Cr VI) from industrial wastewaters represents a highly toxic source at low concentrations. Biological treatments with anaerobic granular biomass are a promising alternative for the Cr VI bioremediation. This study evaluated the Cr VI removal in a range of 5-500 mg/L, using an active anaerobic granular consortium. Two removal mechanisms were differentiated from the assays: 1) biological reduction of 70 mg/L to Cr III at a concentration of 250 mg Cr VI/L and 2) physical bioadsorption of 297 mg of Cr VI/L or 31.39 mg of Cr VI/gbiomass at concentration of 500 mg Cr VI /L. The half-maximal inhibitory concentration (IC50) values for the rate and production of methane were 1.4 and 253 mg/L, respectively. In addition, Cr VI is a biostimulant that increase the methane production, in a range from 5 to 100 mg/L, of the anaerobic consortium. This work demonstrates the potential application of the anaerobic granular consortium in metal bioremediation.

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Poultry farmers in the southeastern of Mexico consider that the productivity of the hens that comes from rearing on floor has a higher productive performance than reared hens in cages, mainly due to higher percentage of egg laying and lower mortality. The aim of this study was to evaluate the productive performance of the laying hen in relation to the type of rearing. A total of 79680 pullets Bovans White of 17 weeks of age were housed in cages with five pullets cage-1 (405 cm2pullet-1). They were divided in two treatments according to their type of rearing (floor vs cage) with four replicates. The study period was from week 20 to week 40 of age. The variables evaluated were daily (%) and cumulative mortality (%), egg production (%), egg weight (g), feed intake (g pullet d-1), cumulative feed intake (g pullet-1), daily and cumulative egg mass, number of eggs per hen housed, egg loss (%) and productivity index. The variables were analyzed using a randomized block design. It was observed that daily and cumulative mortality, feed intake and egg loss was higher (p < 0.05), while the number of eggs per hen housed and productivity index (p < 0.05) was lower for hens in cages. We conclude that it is possible to associate detriments in the productive performance of laying hens based on the type of housing during its growth phase.

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Poultry farmers in the southeastern of Mexico consider that the productivity of the hens that comes from rearing on floor has a higher productive performance than reared hens in cages, mainly due to higher percentage of egg laying and lower mortality. The aim of this study was to evaluate the productive performance of the laying hen in relation to the type of rearing. A total of 79680 pullets Bovans White of 17 weeks of age were housed in cages with five pullets cage-1 (405 cm2pullet-1). They were divided in two treatments according to their type of rearing (floor vs cage) with four replicates. The study period was from week 20 to week 40 of age. The variables evaluated were daily (%) and cumulative mortality (%), egg production (%), egg weight (g), feed intake (g pullet d-1), cumulative feed intake (g pullet-1), daily and cumulative egg mass, number of eggs per hen housed, egg loss (%) and productivity index. The variables were analyzed using a randomized block design. It was observed that daily and cumulative mortality, feed intake and egg loss was higher (p < 0.05), while the number of eggs per hen housed and productivity index (p < 0.05) was lower for hens in cages. We conclude that it is possible to associate detriments in the productive performance of laying hens based on the type of housing during its growth phase.(AU)

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Introducción: La secuencia Moebius se caracteriza por el compromiso congénito de los nervios motor ocular externo y facial, y se puede asociar al compromiso de otros pares craneales y a otros defectos congénitos. Su etiología es multifactorial y no bien definida, actualmente la teoría más aceptada es la disrupción vascular durante el desarrollo del romboencéfalo. Su incidencia exacta se desconoce, pero impresiona estar en aumento y asociada a la exposición prenatal a teratógenos. Objetivos: Analizar las historias clínicas de 30 pacientes con secuencia Moebius y las características de su compromiso ocular. Materiales y métodos: Estudio retrospectivo, transversal, observacional y descriptivo. Se analizaron 30 historias clínicas de pacientes con secuencia Moebius atendidos por vez primera entre el mes de Julio de 1999 y Junio de 2012 por el servicio de Oftalmología del Hospital Garrahan. Resultados: Se estudiaron 30 pacientes 15 de sexo femenino y 15 de sexo masculino, dentro de los antecedentes maternos 7 madres refirieron ingesta de misoprostol y 4 tuvieron metrorragias durante el primer trimestre de embarazo. Todos los pacientes tuvieron compromiso del VII nervio; en 20 pacientes fue bilateral y simétrico; y en los restantes asimétrico. Todos los pacientes tuvieron compromiso del VI nervio bilateral, a algunos de los cuáles se les efectuó cirugía de estrabismo otros están en plan de cirugía y unos pocos no la requirieron por presentar fijación de ambos ojos en posición primaria de la mirada. Conclusión: la secuencia Moebius es una rara patología genética y congénita multifactorial y de compromiso multisistémico que ha visto incrementada su frecuencia desde el uso de ciertos fármacos teratógenos y que obliga a una intervención quirúrgica precoz de neuroortopedistas, oftalmólogos, cirujanos plásticos y control clínico multidisciplinario para brindarles a estos niños las mejores posibilidades de desarrollo funcional y estético reparador (AU)

Introduction: Moebius syndrome is characterized by congenital palsy of the external and facial oculomotpr nerves, and may be associated with involvement of other cranial nerves and congenital defects. The etiology is multifactorial and not well defined. Currently, the most widely accepted theory is a rhombencephalic maldevelopment. The true incidence of Moebius syndrome is unknown, but it seems to be increasing associated with prenatal exposure to teratogenic factors. Objectives: To analyze the clinical charts of 30 patients with Moebius syndrome assessing ocular involvement. Material and methods: A retrospective, cross-sectional, observational study. Thirty clinical charts of patients with Moebius syndrome that were first seen at the Department of Ophthalmology of Hospital Garrahan between July 1999 and June 2012 were assessed. Results: Of the 30 patients 15 were female and 15 male. Maternal history showed seven mothers that received misoprostol and four that had metrorrhagia in the first trimester of pregnancy. All patients had VII cranial nerve involvement; the involvement was bilateral and symmetric in 20 and asymmetric in the remaining patients. All patients had bilateral VI nerve involvement, some of whom underwent surgery for strabismus, others are on the list for surgery, and a few do not require surgery because of fixation of both eyes in primary gaze position. Conclusion: Moebius syndrome is a rare multifactorial genetic and congenital pathology with multisystemic involvement and increased incidence because of the use of teratogenic drugs requiring early surgical intervention by neuroorthopedic and plastic surgeons, and ophthalmologists, and a multidisciplinary follow-up to provide these children with the best possibilities for functional development and aesthetic repair (AU)

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Williams-Beuren syndrome (WBS) is a genetic disorder characterized by physical and intellectual developmental delay, associated with congenital heart disease and facial dysmorphism. WBS is caused by a microdeletion on chromosome 7 (7q11.23), which encompasses the elastin (ELN) gene and about 27 other genes. The gold standard for WBS laboratory diagnosis is FISH (fluorescence in situ hybridization), which is very costly. As a possible alternative, we investigated the accuracy of three clinical diagnostic scoring systems in 250 patients with WBS diagnosed by FISH. We concluded that all three systems could be used for the clinical diagnosis of WBS, but they all gave a low percentage of false-positive (6.0-9.2%) and false-negative (0.8-4.0%) results. Therefore, their use should be associated with FISH testing.

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A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10(-6) and 1 MeV. Neutron and the Bremsstrahlung spectra show the same features regardless of the linac voltage.

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Objetivo. Evaluar clínica y microbiológicamente la implicación de Malassezia sp como agente etiológico de otitis externas en caninos. Materiales y métodos. Se obtuvieron 166 muestras de hisopados óticos de caninos con sintomatología y hallazgos clínicos compatibles con otitis externa durante el periodo comprendido entre julio – diciembre 2008. A partir de las muestras se realizaron cultivos bacteriológicos y micológicos e identificación de género mediante perfiles bioquímicos para cada unos de los microorganismos aislados. Los datos clínicos asociados a la patología fueron consignados en una base de datos y posteriormente analizados en el programa estadístico SPSS 17 Resultados. A partir de la 166 muestras obtenidas, 59% (98) de ellas fueron positivas para el cultivo bacteriológico con predominio de Staphylococcus sp 37% (61) y 73% (121) positivas para Malassezia. De las 121 levaduras aisladas 32.2% fue Malassezia pachydermatis. El análisis estadístico no evidenció diferencias significativas con respecto a las relaciones entre variables (género, edad, raza, tipo de oreja y respuesta inflamatoria por citología) y el aislamiento de Malassezia sp. El nivel de significancia establecido para la prueba fue de 0.05%. Conclusiones. No se observaron asociaciones estadísticas entre las variables género, edad, raza frente a la otitis externa por Malassezia sp. Malassezia sp fue aislada en un 73% de los casos con otitis externa, con participación de diferentes agentes bacterianos especialmente Staphylococcus sp.

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Microcins are a family of low-molecular weight bacteriocins produced and secreted by Gram-negative bacteria. This review is focused on microcin E492, a pore-forming bacteriocin produced by Klebsiella pneumoniae RYC492 that exerts its antibacterial action on related strains. The steps necessary for the production of active microcin E492 involve post-translational modification with a catechol-type siderophore at the C-terminal and proteolytic processing during export to the extracellular space. This bacteriocin has a modular structure, with a toxic domain at the N-terminal and an uptake domain at the C-terminal of the mature protein. The mechanism by which the C-terminal of microcin E492 is recognized by catecholate siderophore receptors is called the "Trojan horse" strategy, because the C-terminal structure mimics essential bacterial elements, which are recognized by the respective receptors and translocated across the outer membrane to exert antibacterial action. The C-terminal uptake module can be exchanged and used with other toxic domains. Microcin E492 also has a cytotoxic effect on malignant human cell lines. The cytotoxic mechanism is through apoptosis, a desired mechanism for cancer therapy. The ability of microcin E492 to form amyloid-like fibrils constitutes a property that can be exploited in the formulation of this bacteriocin as an antitumoral agent, because these fibrils can behave as stable depots to ensure the sustained release of a biologically active molecule. Alternatively, live bacteria can be used as a continuous source of microcin E492 production in specific tumors.

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En una muestra de 436 adolescentes pertenecientes a establecimientos privados, subvencionados y municipalizados de la ciudad de Antofagasta, se evalúan las propiedades psicométricas de la versión en castellano del cuestionario Kiddo-Kindl, destinado a evaluar la calidad de vida en la adolescencia en torno a seis dimensiones. Se encuentra una consistencia interna similar a la reportada en España y una estructura factorial aceptable. Los varones presentan una mejor evaluación de la calidad de vida en algunas dimensiones, al igual que los que autoevalúan como sanos por aquellos que se autodefinen como enfermos. En términos generales este conjunto de dimensiones es buen instrumento de tamizaje para evaluar la calidad de vida de los adolescentes, sin embargo, debe profundizarse el estudio sobre su aplicación en grupos específicos y afinar su estructura factorial, esto último, cuestión relevante para su uso generalizado.

The psychometric properties of the Kiddo-Kindl in Spanish are evaluated in a sample of 436 adolescents from private, semi-private, and public schools of the city of Antofagasta. This instrument is designed to evaluate adolescent quality of life in six dimensions. The internal consistency of the instrument is similar to what has been reported in Spain, with an acceptable factorial structure. Males have a better evaluation of their quality of life in some dimensions, as well as those who consider themselves healthy in comparison to those who consider themselves unhealthy. In general terms, the totality of dimensions are seen adequate as a general diagnostic of adolescent's quality of life. However, it is recommended to investigate the use of this instrument with specific groups, and to improve its factorial structure, which is an important question for its generalized use.

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We report three patients with bilateral choanal atresia in children prenatally exposed to methimazole (MMI) in order to define a MMI embryopathy clinical pattern. The combination of choanal atresia and other specific malformations strongly resembles previously reported patients exposed to MMI in utero. At present, propylthiouracil is considered the best treatment in pregnancies. However in Argentina and some other countries MMI is the only antithyroid drug, possibly posing a significant risk to the unborn fetus.

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En las últimad décadas el óxido nítrico ha pasado de ser un contaminante ambiental a una mólecula implicada en múltiples funciones fisiológicas, actualmente se han multiplicado las investigaciones en torno a sus funciones. El óxido nítrico juega un papel imortnate en la regulación de una serie de procesos fisiológicos como ser: el tono vasomotor, la motilidad intestinal, actúa como un neurotransmisor central y periférico, desemeña un papel fundamental en la funciones del sistema inmune y la fisiologia del os procesos de agregación plaquetaria y leucocitaria. Sus acciones fisioatológiocas incluyen un rol determinante en la génesis del Shock séptico, en el daño tisular resultado de la inflamación, en el envejecimiento motocondrial, en el desarrollo dela rtrosis y la artritis reumatoidea, enfermedades degenerativas dels istema nervioso central y en el daño producido por la isquemia miocárdica y cerebral. Demostrando múltiples aplicaciones terapéuticas en el tratamiento de varias patologías.

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We describe a hemiarthroplasty of the shoulder with an acrylic Judet hip prosthesis, inserted after the excision of a giant cell tumour of the head of the humerus, which functioned well for 39 years.

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