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Semitendinosus Muscle (semitendinosu + muscle)
Selected AbstractsIn vivo proteome dynamics during early bovine myogenesisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 20 2008Thibault Chaze Abstract Myogenesis is a complex process of which the underlying mechanisms are conserved between species, including birds and mammals. Despite a good understanding of the stages of myogenesis, many of the mechanisms involved in the regulation of proliferation of the successive myoblast generations, the cellular transitions cell proliferation/alignment of myoblasts/fusion of myoblasts into myotubes/differentiation of myofibres and the control of total myofibre number still remain unknown. An in vivo proteomic analysis of the semitendinosus muscle from Charolais foetuses, at three specific stages of myogenesis (60, 110 and 180,days postconception), was conducted using 2-DE and MS. Expression profiles of more than 170 proteins were revealed and analysed using two way hierarchical clustering and statistical analysis. Our studies identify, for the first time, distinct proteins of varied biological functions and protein clusters with myogenic processes, such as the control of cell cycle activity and apoptosis, the establishment of cellular metabolism and muscle contractile properties and muscle cell reorganisation. These results are of fundamental interest to the field of myogenesis in general, and more specifically to the control of muscle development in meat producing animals. [source] Relationship of Birth Weight with the Size, Number and Proportion of Fibres in the Pig Semitendinosus MuscleANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2009F. Tristán Summary The objective of this study was to determine the relationship between body weight and the size, number and proportion of muscle fibre types in the pig semitendinosus muscle at birth. Based on weight at birth, 68 specimens selected from 21 different litters from the same farm were allotted in two equal groups (G1 and G2). G1 included 34 piglets ,1.1 kg and G2 34 pigs ,2 kg. Fifteen piglets per group were killed at birth and the remaining 19 piglets in each group were reared until weaning (21 days) and post-weaning (67 days). The weight and total cross-sectional area of the semitendinosus muscle were recorded at birth. Then, type I and type II fibres from the superficial portion of the muscle were identified according to histochemistry and immunohistochemistry techniques and percentages, average size of each fibre type, and the total number of muscle fibres were estimated by morphometry. Birth weight in G1 was 54.74% lower than that in G2. Correspondingly, the total cross-sectional area of the semitendinosus, as well as the size and number of muscle fibres, was significantly lower in G1 (P < 0.001). Weight at birth still influenced weights at weaning and post-weaning, hence it was 43.17% and 28.38% lower respectively in G1. It is concluded that pig weight at birth is associated with muscle cellularity of the semitendinosus muscle of pig, which may influence the postnatal muscle growth and final size of muscle fibres and meat quality. [source] Increased rigidity of the chiral centre of tocainide favours stereoselectivity and use-dependent block of skeletal muscle Na+ channels enhancing the antimyotonic activity in vivoBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2001Sophie Talon Searching for the structural requirements improving the potency and the stereoselectivity of Na+ channel blockers as antimyotonic agents, new derivatives of tocainide, in which the chiral carbon atom is constrained in a rigid ,-proline or pyrrolo-imidazolic cycle, were synthesized as pure enantiomers. Their ability to block Na+ currents, elicited from ,100 to ,20 mV at 0.3 Hz (tonic block) and 2 , 10 Hz (use-dependent block) frequencies, was investigated in vitro on single fibres of frog semitendinosus muscle using the vaseline-gap voltage-clamp method. The ,-proline derivative, To5, was 5 and 21 fold more potent than tocainide in producing tonic and 10 Hz-use-dependent block, respectively. Compared to To5, the presence of one methyl group on the aminic (To6) or amidic (To7) nitrogen atom decreased use-dependence by 2- and 6-times, respectively. When methylene moieties were present on both nitrogen atoms (To8), both tonic and use-dependent block were reduced. Contrarily to tocainide, all proline derivatives were stereoselective in relation to an increased rigidity. A further increase in the molecular rigidity as in pyrrolo-imidazolic derivatives markedly decreased the drug potency with respect to tocainide. Antimyotonic activity, evaluated as the shortening of the time of righting reflexes of myotonic adr/adr mice upon acute drug in vivo administration was 3 fold more effective for R-To5 than for R-Tocainide. Thus, constraining the chiral centre of tocainide in ,-proline cycle leads to more potent and stereoselective use-dependent Na+ channel blockers with improved therapeutic potential. British Journal of Pharmacology (2001) 134, 1523,1531; doi:10.1038/sj.bjp.0704366 [source] EFFECT OF FROZEN TEMPERATURE AND STORAGE TIME ON CALPAINS, CATHEPSINS (B, B + L, H AND D) AND THEIR ENDOGENOUS INHIBITORS IN GOAT MUSCLESJOURNAL OF FOOD BIOCHEMISTRY, Issue 2 2006N.S. NAGARAJ ABSTRACT The effects of frozen storage on the biochemical properties of myofibrils, muscle proteinases (cathepsins and calpains) and their endogenous inhibitors were investigated. Longissimus dorsi, biceps femoris, semimembranosus and semitendinosus muscles from goat were frozen (,15C) and studied up to 120 days. The results showed that the percentage change in sarcomere length was 8.4,13.1. The calpain activity was determined after separation on a diethylaminoethyl,Sephacel column (Sigma, St. Louis, MO). Significantly greater percentage of calpain II activity was recovered when compared to calpain I. There was a 15,25% loss in calpastatin inhibitory activity, and the cystatin level fell by 11,16% after 80 days. Cathepsin B, B + L, H and D were very stable when compared to calpains. The calcium concentration may also be the factor for calpain activation. The sodium dodecyl sulfate,polyacrylamide gel electrophoresis result showed the appearance of 55 kDa components. It was concluded that calpains, not cathepsins, play an important role in the proteolysis of myofibrillar proteins at the freezing temperature. [source] Effects of muscle type on beef taste-traits assessed by an electric sensing systemANIMAL SCIENCE JOURNAL, Issue 5 2010Koichi CHIKUNI ABSTRACT To assess the role of muscle fiber type in beef taste-traits, we analyzed cooked meats from bovine masseter, diaphragm, psoas major, longissimus thoracis, and semitendinosus muscles with an electric taste sensing system (INSENT SA402B). The system is composed of five taste sensors of polymer membranes fixing different lipids. The sensors, CT0, CA0, AAE, C00 and AE1 are designed to respond to the individual tastes of salty, sour, umami, bitter and astringent, respectively. The system found significant differences in the converted outputs of CA0 (cvCA0), C00 (cvC00) and AE1 (cvAE1) among the bovine muscles. The slow-type muscles (masseter and diaphragm) showed lower cvCA0, higher cvC00, and higher cvAE1 than did the fast-type muscles (psoas major, longissimus thoracis, and semitendinosus). Lactic acid content was different among muscle types and was highly related to the cvCA0 output and pH. carbonyl compounds and free fatty acids were higher in the slow-type muscles. Free fatty acids were major components causing the difference in the C00 output among the muscle types. Iron content was also different among the muscle types and related to the cvC00 and cvAE1 outputs. These results suggested that the muscle fiber type affects the beef taste characteristics. [source] | |||||||||||||