4,774 research outputs found
Enzymatic preparation of structured triacylglycerides containing γ-linolenic acid
with the addition of molecular sieves (MS) at different addition times (3, 9, 12 and 15 h) and loads (2.5, 5, 10 and 15%, based on the total weight of substrates), the enrichment of GLA from evening primrose oil (EPO) and 1- butanol (BtOH) was improved via Candida rugosa lipase-catalysed esterification reactions. Secondly, the GLAenriched fraction was separated by thin-layer chromatography (TLC) to be further set to react during the third step in the presence of glycerol and Candida antarctica fraction B (CALB), under different enzyme loadings (5, 10, 15 and 20%, based on the total weight of substrates), temperatures (30, 40, 50 and 60 ◦C) and substrates molar ratios (1:1, 2:1, 3:1 and 4:1, GLA:glycerol). 60% of STAG containing 49 wt% of GLA were produced by using 15% of CALB at 60 ◦C and a 3:1 molar ratio.Conacyt: Beca no. 328716 UAEMex: Proyecto 3866/2015/PI
Xanthinuria: a rare cause of urolithiasis in the cat
Xanthinuria is a very rare disease in cats. Its etiology may have a genetic origin or may be due to an iatrogenic xan- thine-dehydrogenase inhibition that nally results in urolithiasis. The present work reports two cases of xanthine uro- lithiasis in European Shorthair unrelated male and female cats. Both uroliths were analyzed by stereoscopic microsco- py, infrared spectroscopy and scanning electron microscopy. Besides the report of these two clinical cases, a detailed pathophysiologic review and some updated recommendations for diagnosis and treatment for this condition were done.La xantinuria es una patología que se presenta raramente en los gatos. Su etiología puede tener origen genético o de- berse a una inhibición yatrogénica de la enzima xantina deshidrogenasa, que generalmente se mani esta con urolitiasis. En este trabajo se informa el hallazgo de dos urolitos de xantina en dos gatos, un macho y una hembra, de raza Euro- pea de pelo corto, no emparentados. Los urolitos fueron analizados mediante microscopía estereoscópica, espectrosco- pía infrarroja y microscopía electrónica de barrido. Además de informar sobre estos casos clínicos, se hace una revisión detallada de la siopatología y de las recomendaciones actuales para el diagnóstico y manejo médico de esta patología.Se agradece al Consejo Nacional de Ciencia y Tecnolo- gía de México (CONACyT) y al Programa de Mejora- miento del Profesorado de la Secretaria de Educación Pública de México 2011 (PROMEP-SEP), el apoyo complementario para la realización de este trabajo
Lipofection improves gene targeting efficiency in E14 TG2a mouse embryonic stem cells
Electroporation has been the method of election for transfection of murine embryonic stem cells for over 15 years; however, it is a time consuming protocol because it requires large amounts of DNA and cells, as well as expensive and delicate equipment. Lipofection is a transfection method that requires lower amounts of cells and DNA than electroporation, and has proven to be effi cient in a large number of cell lines. It has been shown that after lipofection, mouse embryonic stem cells remain pluripotent, capable of forming germ line chimeras and can be transfected with greater effi ciency than with electroporation; however, gene targeting of mouse embryonic stem cells by lipofection has not been reported. The objective of this work was to fi nd out if lipofection can be used as effi ciently as electroporation for regular gene targeting protocols. This context compares gene targeting effi ciency between these techniques in mouse embryonic stem cells E14TG2a, using a gene replacement type vector. No differences were found in gene targeting effi ciency between groups; however, lipofection was three times more effi cient than electroporation in transfection effi ciency, which makes lipofection a less expensive alternative method to produce gene targeting in mouse embryonic stem cells
Alternative system to measure hydrogen content in molten aluminium using an electrochemical sensor
1037-1042The most reliable techniques for the direct measurement of hydrogen content in liquid aluminium are based on Sievert’s law or use electrochemical probes introduced directly in liquid aluminium. The main drawback of these methods is the high cost of the equipment. An alternative apparatus has been developed and tested. This equipment combines a widely used and much cheaper hydrogen electrochemical sensor with the procedure already patented and commonly used by gas recirculation techniques. The device has been constructed and calibrated using gaseous mixtures of known hydrogen content. For validation, the results obtained with this apparatus have been compared with hydrogen content measurements in liquid aluminium using the commercial Alscan equipment in an industrial facility. Experimental results suggest that the apparatus proposed in this work is capable of detecting hydrogen content in liquid aluminium obtaining measurements that are in a good agreement with those obtained using the commercial Alscan equipment. On the other hand, results also suggest that it is important to take into account the operating atmospheric pressure to correct the readings obtained from Alscan when operating at atmospheric pressure levels far from 1 atm
Alternative system to measure hydrogen content in molten aluminium using an electrochemical sensor
The most reliable techniques for the direct measurement of hydrogen content in liquid aluminium are based on Sievert’s law or use electrochemical probes introduced directly in liquid aluminium. The main drawback of these methods is the high cost of the equipment. An alternative apparatus has been developed and tested. This equipment combines a widely used and much cheaper hydrogen electrochemical sensor with the procedure already patented and commonly used by gas recirculation techniques. The device has been constructed and calibrated using gaseous mixtures of known hydrogen content. For validation, the results obtained with this apparatus have been compared with hydrogen content measurements in liquid aluminium using the commercial Alscan equipment in an industrial facility. Experimental results suggest that the apparatus proposed in this work is capable of detecting hydrogen content in liquid aluminium obtaining measurements that are in a good agreement with those obtained using the commercial Alscan equipment. On the other hand, results also suggest that it is important to take into account the operating atmospheric pressure to correct the readings obtained from Alscan when operating at atmospheric pressure levels far from 1 atm
Modeling human endometrial decidualization from the interaction between proteome and secretome
CONTEXT: Decidualization of the human endometrium, which involves morphological and biochemical modifications of the endometrial stromal cells (ESCs), is a prerequisite for adequate trophoblast invasion and placenta formation. OBJECTIVE: This study aims to investigate the proteome and secretome of in vitro decidualized ESCs. These data were combined with published genomic information and integrated to model the human decidualization interactome. DESIGN: Prospective experimental case-control study. SETTING: A private research foundation. PATIENTS: Sixteen healthy volunteer ovum donors. INTERVENTION: Endometrial samples were obtained, and ESCs were isolated and decidualized in vitro. MAIN OUTCOME MEASURES: Two-dimensional difference in-gel electrophoresis, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, Western blot, human protein cytokine array, ELISA, and bioinformatics analysis were performed. RESULTS: The proteomic analysis revealed 60 differentially expressed proteins (36 over- and 24 underexpressed) in decidualized versus control ESCs, including known decidualization markers (cathepsin B) and new biomarkers (transglutaminase 2, peroxiredoxin 4, and the ACTB protein). In the secretomic analysis, a total of 13 secreted proteins (11 up- and 2 down-regulated) were identified, including well-recognized markers (IGF binding protein-1 and prolactin) and novel ones (myeloid progenitor inhibitory factor-1 and platelet endothelial cell adhesion molecule-1). These proteome/secretome profiles have been integrated into a decidualization interactome model. CONCLUSIONS: Proteomic and secretomic have been used as hypothesis-free approaches together with complex bioinformatics to model the human decidual interactome for the first time. We confirm previous knowledge, describe new molecules, and we have built up a model for human in vitro decidualization as invaluable tool for the diagnosis, therapy, and interpretation of biological phenomena.The participation of T.G.-G. was supported by a grant of the Ministry of Education and Science AP2007-04066 (FPU). CNIC was supported by the Spanish Ministry of Science and Innovation and the Pro-CNIC Foundation.S
Información climática asociada a estaciones productivas para el ajuste de modelos estadísticos de sistemas bovinos bajo condiciones extensivas
Artículo de investigación publicado en revista internacional indizada.El objeto de este estudio fue desarrollar una metodología para clasificar épocas de nacimiento (EN) y evaluar su impacto en indicadores productivos al compararlas con un método tradicional de clasificación. Con información meteorológica, se generó un índice de aridez para clasificar las EN. Las EN propuesta y tradicional se compararon, incluyéndolas como grupo contemporáneo (GC= hato, sexo, año y EN) a modelos de evaluación genética de caracteres de peso vivo. Fueron estimados los componentes de varianza y valores genéticos (DEP) con sus exactitudes. La clasifica- ción propuesta explicó mayor variabilidad que la clasificación tradicional (≥9,8%). Los parámetros genéticos mostraron cambios importantes, siendo los más evidentes en peso al destete. Los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0,01). Se observó una mejora de estructura en los GC. Para los dos caracteres evaluados las correlaciones entre los valores genéticos de los animales fueron diferentes, lo que indica cambio en la jerarquización. Este método de clasificación de EN puede ayudar a mejorar el ajuste de modelos estadísticos en condiciones en las que exista la información climática necesaria para su implementación.Los autores agradecen al Consejo Nacional de Cien- cia y Tecnología por el financiamiento del proyecto CB168207 y al Instituto Politécnico Nacional a través del proyecto SIP20150746
Versatile Graphene-Based Platform for Robust Nanobiohybrid Interfaces
Technologically useful and robust graphene-based interfaces for devices
require the introduction of highly selective, stable, and covalently bonded
functionalities on the graphene surface, whilst essentially retaining the
electronic properties of the pristine layer. This work demonstrates that highly
controlled, ultrahigh vacuum covalent chemical functionalization of graphene
sheets with a thiol-terminated molecule provides a robust and tunable platform
for the development of hybrid nanostructures in different environments. We
employ this facile strategy to covalently couple two representative systems of
broad interest: metal nanoparticles, via S-metal bonds, and thiol-modified DNA
aptamers, via disulfide bridges. Both systems, which have been characterized by
a multi-technique approach, remain firmly anchored to the graphene surface even
after several washing cycles. Atomic force microscopy images demonstrate that
the conjugated aptamer retains the functionality required to recognize a target
protein. This methodology opens a new route to the integration of high-quality
graphene layers into diverse technological platforms, including plasmonics,
optoelectronics, or biosensing. With respect to the latter, the viability of a
thiol-functionalized chemical vapor deposition graphene-based solution-gated
field-effect transistor array was assessed
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