Acute sleep deprivation induces synaptic remodeling at the soleus muscle neuromuscular junction in rats.

Sleep is important for cognitive and physical performance. Sleep deprivation not only affects neural functions but also results in muscular fatigue. A good night's sleep reverses these functional derangements caused by sleep deprivation. The role of sleep in brain function has been extensively studied. However, its role in neuromuscular junction (NMJ) or skeletal muscle morphology is sparsely addressed although skeletal muscle atonia and suspended thermoregulation during rapid eye movement sleep possibly provide a conducive environment for the muscle to rest and repair; somewhat similar to slow-wave sleep for synaptic downscaling. In the present study, we have investigated the effect of 24 h sleep deprivation on the NMJ morphology and neurochemistry using electron microscopy and immunohistochemistry in the rat soleus muscle. Acute sleep deprivation altered synaptic ultra-structure viz. mitochondria, synaptic vesicle, synaptic proteins, basal lamina, and junctional folds needed for neuromuscular transmission. Further acute sleep deprivation showed the depletion of the neurotransmitter acetylcholine and the overactivity of its degrading enzyme acetylcholine esterase at the NMJ. The impact of sleep deprivation on synaptic homeostasis in the brain has been extensively reported recently. The present evidence from our studies shows new information on the role of sleep on the NMJ homeostasis and its functioning.

Ultrastructural analysis of collagen fibril diameter distribution in cleft lip.

OBJECTIVE: A preliminary study to determine collagen fibril diameter (CF-ED) distribution on medial and lateral sides of cleft lip (CL). MATERIAL AND METHODS: Tissue samples from medial and lateral sides of CL were fixed in 2.5% glutaraldehyde and 1% osmium tetroxide and embedded in Araldite CY212 resin for transmission electron microscopy. The analysis of CF-ED was performed using the ImageJ program. To characterize the packaging of collagen fibrils (CFs) in the two tissues, we estimated the collagen number density (CF-ND) and fibril-area-fraction (FAF). Differences in measurements across the two sides were calculated using Wilcoxon signed-rank test. RESULTS: The CF-ED was statistically significantly (p < 0.001) smaller on the medial side (45.69 ± 7.89 nm) than on the lateral side (54.18 ± 7.62 nm). The medial side had a higher CF-ND and a higher percentage of FAF than the lateral side. CONCLUSION: Our finding of a smaller CF-ED and higher CF-ND and FAF for the medial side suggests possible differences in size and distribution of CFs between medial and lateral sides of CL. This finding provides knowledge toward underlying tissue biomechanics that may help reconstruction of perioral tissue scaffolds, ultimately resulting in better treatment of patients with oral clefts.

Synthesis, Structural and Optical Characterization of Copper and Rare Earth doped CdS Nanoparticles.

Cadmium sulphide (CdS) nanoparticles doped with Cu(2+) and co-doped with rare earth metallic ions (RE3(+)) have been synthesized by co-precipitation method. The synthesized nanoparticles were been characterized by powder X-ray diffraction studies (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), particle size by dynamic light scattering (DLS), UV-visible spectroscopy (UV), and photoluminescence (PL) studies. It is observed that CdS nanoparticles can be co-doped with copper and rare earth metallic ions without altering XRD pattern as indicated by X-ray diffraction results. SEM results show that synthesized particles show spherical aggregation and TEM results show that these particles assembled to give a flower-like morphology. Absorption spectra of all the samples show strong blue shift from bulk CdS. Interesting luminescence pattern with enhanced intensity has been observed for co-doped CdS nanoparticles at room temperature.