BACKGROUND Sperm hyperactivation is critical to fertilization, because it is required for penetration of the zona pellucida. Hyperactivation may also facilitate release of sperm from the oviductal storage reservoir and may propel sperm through mucus in the oviductal lumen and the matrix of the cumulus oophorus. Hyperactivation is characterized by high amplitude, asymmetrical flagellar bending. ...

Intracellular Ca2+ stores play a central role in the regulation of cellular [Ca2+](i) and the generation of complex [Ca2+] signals such as oscillations and waves. Ca2+ signalling is of particular significance in sperm cells, where it is a central regulator in many key activities (including capacitation, hyperactivation, chemotaxis and acrosome reaction) yet mature sperm lack endoplasmic reticul...

objectives the overall goal of this study was to carry out a set of comparative analyses of arsr gene in plasmid r773 and bacterial chromosome from escherichia coli bl-21(de3). methods pdb and ncbi databases and chimera, mega4, clc main workbench software and 3d-jigsaw and embl-ebi servers were applied to perform this study. by using these software and servers, multiple analyses including deter...

Compared to efficient and secure female contraception, a vasectomy and condoms are the only options for men. The choice of male contraceptive methods is limited, so contraception mainly rests on the shoulders of women. Several concepts are considered: testosterone administration--inhibiting pituitary secretion of lutropin (LH) and follicle stimulating hormone (FSH), progestogen--affecting the s...

background: tumour suppressor genes such as tp53, brca1 and rad51 are involved in dna repair and their malfunctions result in genomic instability and cancer. wild type (wt) tp53 binds to brca1and rad51 in vivo and in vitro. however, mutated tp53 in tumours can interfere with wt tp53 function. we studied how mutation of tp53 in mda-mb-468 cell line could affect its binding capacity and interfere...

nine multiparous lactating cows averaging 171 days in milk were divided according to days in milk and milk production into three 3×3 latin squares with three 3-week periods to investigate the effect of rumen degradable protein on milk urea nitrogen. diets were formulated to provide 3 concentrations of dietary rumen degradable protein (9.8, 10.8, and 11.8% of dry matter), while rumen undegradabl...

background: the purity and correct folding of a recombinant protein is critical for any structural, biochemical and vaccine design studies. plasmodium vivax duffy binding protein-ii is a leading vaccine candidate for vivax malaria. in the present study, the purification process of recombinant dbp-ix (a variant form of pvdbp-ii) was optimized to achieve the highest yield and purity. moreover, na...

in the near future, design of a new generation of drugs targeting proteins will be required. considering the complex bond between the drug and protein, the structure and stability of the target protein should be considered. so far, a series of in vitro investigations have been conducted with the aim of predicting drug-biological medium interactions. in these studies, use of spectroscopic method...

conclusions we found considerable relationship between s1a/m1a, s1a/m2, s2/m2 and s1c/m1a and some gastric disorders. further studies about the role of h. pylori virulence factors and gastric disorders were recommended. results the frequency of the vaca genotypes, sa1/m1, s1a/m1b, s1a/m2, s1b/m1a, s1b/m1b, s1b/m2, s1c/m1a, s1c/m1b, s1c/m2, s2/m1a, s2/m1b and s2/m2 were 27(6.6%), 8(4.3%), 45(28....