Determination of an Optimal Membrane-permeable Cryoprotectant Addition and Dilution Protocol for Water Buffalo Spermatozoa.

BACKGROUND: There is a possibility to reduce the toxicity of glycerol and osmotic stress of DMSO by lowering their concentrations in freezing extenders. OBJECTIVE: To investigate the effect of glycerol and DMSO in tris-citric acid based extender on post- thaw quality of buffalo (Bubalus bubalis) bull spermatozoa. MATERIALS AND METHODS: Semen was collected from five adult buffalo bulls with artificial vagina. Five aliquots of semen per bull were separated for dilution with the treatment extenders. The first aliquot was diluted at 37C with 6 percent glycerol (T1). The second aliquot was diluted at 37C with extenders containing 4.5 percent glycerol and 1.5 percent DMSO (T2). The third aliquot was diluted with extenders containing 4.5 percent glycerol at 37C and 1.5 percent DMSO at 4С (T3). The fourth aliquot was diluted with extenders containing 1.5 percent DMSO at 37C and 4.5 percent glycerol at 4С (T4). The fifth aliquot was diluted with extender containing 2.5percent DMSO at 37 as well as at 4C (T5). The final concentration of spermatozoa was 50×106/ml in all the treatment groups. Semen was cooled from 37 to 4C in 2 h and equilibration was done at 4 C for 4 h. Later on, packing of cooled semen was undertaken in 0.54 ml French straws and frozen in a programmable cell freezer. RESULTS: At post thawing, treatment groups T1 and T2 yielded significant (P < 0.05) outcome for CASA parameters, longevity, acrosomal integrity, plasma membrane integrity, mitochondrial transmembrane potential and DNA integrity. CONCLUSION: We concluded that by decreasing glycerol concentration (4.5 percent) and combining it with DMSO (1.5 percent) at 37C (T2) in tris-citric acid based extender provided similar results to those observed when glycerol (6 percent) alone is used at 37C (T1) for improving the post-thaw quality of buffalo bull spermatozoa.

Retinoid BMS411 (4-{[(5,5-dimethyl-8-phenyl-5,6-dihydronaphthalen-2-yl) carbonyl] amino} benzoic acid), a potential inhibitor of NS5A protein of hepatitis C virus, a candidate for combined therapy of hepatitis C infection.

Hepatitis C infection is a serious health issue worldwide caused by hepatitis C virus (HCV). There is an urgent need of search for new direct acting antiviral drugs due to the rapid development of drug resistance. The HCV NS5A protein is involved in creating resistance against antiviral therapy and there are also many reports that vitamin A deficiency is associated with non-responsiveness to antiviral treatment in HCV infected patients. So the present in silico study was aimed to find the relation between vitamin A deficiency and the NS5A protein's function in antiviral resistance. Structure of NS5A protein was predicted by using I-Tasser (Interactive Tasser). Previous data on conservative domains and dimer formation were confirmed by using a series of current computational methods. The structure was employed for molecular docking analysis to investigate the interaction of ligand BMS411 (4-[(5,5-dimethyl-8-phenyl-6H-naphthalene-2-carbonyl)amino]benzoic acid), a vitamin A related compound with NS5A protein. Docking analysis showed that retinoid BMS411 can bind to HCV NS5A protein and may act as inhibitor of this protein. The functionally interacting amino acid residues surrounding the ligand molecule were identified and were shown to be involved in the formation of binding pocket. The present study suggests that retinoids may play an important role in the improvement of the outcomes of antiviral therapy against HCV through interaction with NS5A and inhibition of this protein. It is of great importance to check and verify if other retinoids could act as NS5A inhibitors.

Effects of d-α-tocopherol and dietary energy on growth and health of preruminant dairy calves.

To observe the effects of supplemental dietary d-α-tocopherol in relation to dietary energy on growth and immune status in dairy calves, 32 newborn Holstein bull calves were assigned to 1 of 4 treatments for 5 wk in a 2 × 2 factorial, randomized complete block, split-plot design. Calves received moderate growth (MG) or low growth (LG) all-milk dietary treatments, formulated to support daily gains of 0.5 or 0.25 kg/d, respectively, per the dietary energy recommendation for milk-fed calves according to the National Research Council's Nutrient Requirements of Dairy Cattle. Calves in both groups were either injected i.m. with Vital E-A+D (injectable solution of vitamins E, A, and D) on d 1 and supplemented with Emcelle Tocopherol (micellized vitamin E) via milk daily (MG-S and LG-S), or were not supplemented (MG-C and LG-C) during the study period. Total weight gain of MG calves was greater than that of LG calves and tended to be greater in MG-S calves than in MG-C calves. Calves receiving vitamin supplementation demonstrated greater concentrations of plasma α-tocopherol, retinol, and 25-(OH)-vitamin D than did control calves, whereas MG calves demonstrated a lower concentration of plasma α-tocopherol than did LG calves. The apparent increased utilization of α-tocopherol by MG calves was accompanied by a rise in serum haptoglobin, a positive acute-phase protein and indicator of inflammation, especially in MG-C calves. Serum amyloid A, also a positive acute-phase protein, was not different among groups, but was elevated from baseline in all groups during wk 1 through 3. Plasma IgG1 concentrations were higher in MG-S and LG-S calves than in their nonsupplemented dietary counterparts, whereas plasma IgG2, IgA, and IgM concentrations were not different among groups. In summary, dietary supplementation of d-α-tocopherol improved plasma α-tocopherol status and tended to increase growth in calves fed for 0.5 kg of average daily gain. Vitamin supplementation ameliorated the rise of serum haptoglobin associated with acute inflammation in MG calves, and may have improved passive transfer of maternal antibody. These results indicate a role for α-tocopherol in prevention of proinflammatory state associated with greater dietary energy and onset of infectious disease.