Localization of TGF-beta receptors [type II] in the adult rat muscles

To date, signal transduction of transforming growth factor-beta [TGF-beta] members is well known to occur through three main identified types of protein receptors. Type II receptors [T beta R-II] were found to be prime movers of the signaling process of TGF-beta candidates. Because TGF-beta 2 localizes a neuromuscular junctions [nmjs] of the adult Wistar rats, it would be expectable accumulation of TGF-beta receptors at the same location, i.e. nmjs. Two groups of six Wistar rats were subject to both confocal immunohistochemistry and immunoelectronmicroscopy studies. The main objective of this study was to localize T beta R-II particularly at the nmjs. The results do not prove a clear-cut evidence of T beta R-II accumulation at the nmjs. The receptors would rather scatter near and around the intracellular organelles such as mitochondria in a variable manner. Several assumptions were put forward to explain such variability

Cellular dynamics of transforming growth factor beta-2 [TGF-beta [2]] in the postnatal developing rat muscles

Transforming growth factor beta-2 [TGF-beta2] is a multifunctional superfamily. TGF-beta2 has been found to be involved in multiple cellular functions including; cell growth, proliferation, differentiation and death. However, the specific function of muscle-derived TGF-beta2 has not been determined. The localization as well as the study of time course of muscle-derived TGF-beta2 is a crucial step towards understanding the role of TGF-beta in the postnatal developing skeletal muscle. Extensor digitorum longus muscles of Wistar rats at ages 0,2,4,7,13,16,19,21,42 and 90 postnatal days were used. The muscles were processed for double labeling immunohistochemistry and confocal examination. Anti-TGF-beta2 antibodies and alpha-bungarotoxin were used to localize TGF-beta 2 in the muscle fibers of the different age groups. The results showed that TGF-beta2 localizes at the mature neuromuscular junction [nmj] after being diffuse throughout the immature muscle cell. The time curse of muscle derived TGF-beta2 can be divided into 3 phases; the first plateau phase, second fluctuant phase and third plateau phase. The second phase demonstrated a sudden increase of muscle derived TGF-beta2 ratio at the nmj coinciding with the timing of synaptic eliminate on phenomenon of the muscle fibers

forearm and wrist circumferences as predictors for hand-grip strength

In the present study, a random sample of 200 adults [100 of either sex] was chosen from Cairo city. Their ages ranged between 16.5-23 years. They were subjected to anthropometeric measurements which included: weight, hight, lengths, circumferences and skinfolds of the upper limb on both sides. Hand-grip strength was assessed in all subjects of the sample. A comparative study of the measured variables in both sexes has been established. Weight and circumferences of the arm, forearm and wrist demonstrated the highest correlation with the hand grip in both males and females. By exclusion, forearm and wrist circumferences were the nearest to be relied upon for the indirect evaluation of the hand-grip strength in either sex. Scattergrams and regression equations were constructed for that purpose using both forearm and wrist circumferences. It should be emphasized that these equations are age, sex and population specific. The clinical significance of the present results was assessed. Other measurements could be incorporated in further studies to improve the sensitivity of the proposed regression equations