49 research outputs found

    Impact of the calcium form of β-hydroxy-β-methylbutyrate upon human skeletal muscle protein metabolism

    Get PDF
    Background & aims: β-hydroxy-β-methylbutyrate (HMB) is purported as a key nutritional supplement for the preservation of muscle mass in health, disease and as an ergogenic aid in exercise. Of the two available forms of HMB (calcium (Ca-HMB) salt or free acid (FA-HMB)) – differences in plasma bioavailability have been reported. We previously reported that ∼3 g oral FA-HMB increased muscle protein synthesis (MPS) and reduced muscle protein breakdown (MPB). The objective of the present study was to quantify muscle protein metabolism responses to oral Ca-HMB. Methods: Eight healthy young males received a primed constant infusion of 1,2 13C2 leucine and 2H5 phenylalanine to assess MPS (by tracer incorporation in myofibrils) and MPB (via arterio-venous (A-V) dilution) at baseline and following provision of ∼3 g of Ca-HMB; muscle anabolic (MPS) and catabolic (MPB) signalling was assessed via immunoblotting. Results: Ca-HMB led a significant and rapid (<60 min) peak in plasma HMB concentrations (483.6 ± 14.2 μM, p < 0.0001). This rise in plasma HMB was accompanied by increases in MPS (PA: 0.046 ± 0.004%/h, CaHMB: 0.072 ± 0.004%/h, p < 0001) and suppressions in MPB (PA: 7.6 ± 1.2 μmol Phe per leg min−1, Ca-HMB: 5.2 ± 0.8 μmol Phe per leg min−1, p < 0.01). Increases in the phosphorylation of mTORc1 substrates i.e. p70S6K1 and RPS6 were also observed, with no changes detected in the MPB targets measured. Conclusions: These findings support the pro-anabolic properties of HMB via mTORc1, and show that despite proposed differences in bioavailability, Ca-HMB provides a comparable stimulation to MPS and suppression of MPB, to FA-HMB, further supporting its use as a pharmaconutrient in the modulation of muscle mass

    A draft human pangenome reference

    Get PDF
    Here the Human Pangenome Reference Consortium presents a first draft of the human pangenome reference. The pangenome contains 47 phased, diploid assemblies from a cohort of genetically diverse individuals. These assemblies cover more than 99% of the expected sequence in each genome and are more than 99% accurate at the structural and base pair levels. Based on alignments of the assemblies, we generate a draft pangenome that captures known variants and haplotypes and reveals new alleles at structurally complex loci. We also add 119 million base pairs of euchromatic polymorphic sequences and 1,115 gene duplications relative to the existing reference GRCh38. Roughly 90 million of the additional base pairs are derived from structural variation. Using our draft pangenome to analyse short-read data reduced small variant discovery errors by 34% and increased the number of structural variants detected per haplotype by 104% compared with GRCh38-based workflows, which enabled the typing of the vast majority of structural variant alleles per sample

    Planeacion de los experimentos

    No full text
    A detailed discussion is presented on the general concepts concerning the planning of expt., with emphasis on the exptl. approach, the basic elements of the expt., and information analysis. (CIAT)Se discuten en detalle los conceptos generales sobre la planeacion de expt., con enfasis en el enfoque exptl., los elementos basicos del expt. y el analisis de la informacion. (CIAT

    Guía de estudio para ser usada como complemento de la unidad audiotutorial sobre el mismo tema

    No full text

    La heterogeneidad del suelo y los ensayos de uniformidad [conjunto audiotutorial]

    No full text

    Pressure and temperature combination for inactivation of soymilk trypsin inhibitors

    No full text
    High hydrostatic pressure (HHP) processing, an emerging technology for food preservation, in combination with thermal treatment (250/50, 550/19, 550/65, and 550/80 MPa/�C) was applied to soymilk made from previously soaked soybeans (in distilled water or 0.5% sodium bicarbonate solution). First order kinetics constants ranging from 0.081 to 0.217 min-1, for residual trypsin, were estimated in soymilk from soaked soybeans at selected pressure-temperature combinations. Residual trypsin, at 550 MPa and 80 �C, was high at higher HHP holding times. The highest percentage of residual trypsin (76%) was estimated after a 15 min holding time. The use of sodium bicarbonate for soaking of soybeans synergistically decreased the trypsin inhibitor activity in soymilk in comparison with residual trypsin using distilled water alone. � 2009 Elsevier Ltd. All rights reserved

    Determinación of aflatoxin and fumonisin levels through ELISA and HPLC, on tilapia feed in Nayarit, México

    No full text
    A survey of fungal contamination and presence of aflatoxins (AFs) and fumonisins (FBs) in 30 feed samples collected from 10 tilapia farms during three seasons in Nayarit State, located in north-western Mexico, was carried out using ELISA as screening and High-Performance Liquid Chromatography (HPLC) as confirmatory method. Mycobiota included Aspergillus flavus and Fusarium spp. AFs were detected in 63.3% of samples using ELISA, but confirmation by HPLC revealed that all samples were under the detection limit. Regarding to FBs, positive samples were detected using both methods, with 19 positive samples (60% of total) by ELISA and 14 positive samples (46.6% of total) by HPLC and levels ranging from 0.148 to 2.587 mg/kg. Correlation was observed between both methods (r = 0.516, p = 0.004) for FBs results. No sample exceeded the European maximum levels for any of the mycotoxins. Water activity of samples ranged from 0.345 to 0.655, suggesting that mycotoxin occurrence is probably related to raw material contamination.Se llevó a cabo un estudio de contaminación por hongos y presencia de aflatoxinas (AF) y fumonisinas (FB) en 30 muestras de pienso de 10 granjas de tilapia durante tres temporadas en el estado de Nayarit, en el noroeste de México, Performance Liquid Chromatography (HPLC) como método de confirmación. Mycobiota incluyó Aspergillus flavus y Fusarium spp. AFs se detectaron en el 63,3% de las muestras utilizando ELISA, pero la confirmación por HPLC reveló que todas las muestras estaban bajo el límite de detección. En cuanto a FBs, se detectaron muestras positivas utilizando ambos métodos, con 19 muestras positivas (60% del total) por ELISA y 14 muestras positivas (46,6% del total) por HPLC y niveles de 0,148 a 2,587 mg / kg. Se observó correlación entre ambos métodos (r = 0,516, p = 0,004) para los resultados de FBs. Ninguna muestra superó los niveles máximos europeos para ninguna de las micotoxinas. La actividad de agua de las muestras varió de 0,345 a 0,655, lo que sugiere que la presencia de micotoxinas probablemente esté relacionada con la contaminación de la materia prima
    corecore