Bovine sperm

In mammals the histones are removed and replaced by transition basic proteins in mid-spermatids and then the transition basic proteins are replaced by protamines in late spermitids and sperm [119]. In mouse and rat sperm, histones removal is complete or nearly so [119,120], but in humans 15% of the DNA remains associated with histones [121]. In bovine sperm more than 99% of the histones are removed, but CENP-A is quantitatively retained [122]. This retained CENP-A could be part of an epigenetic mark that allows the positions of the centromeres to be retained in sperm and on the paternal chromosomes of the zygote. 

Cesari et al. (2007) demonstrated on bovine and human sperm in vitro that potato aspartic proteases 1 and 3 are effective spermicidal compounds. Spermicidal activity is due to membrane permeabilization and is not related to the proteolytic activity. Cesari et al. (2007) suggest vaginal contraception as a possible applieation. 

Cytosine and thymine were first isolated by hydrolysis of calf thymus tissue by Albrecht Kossel (1853-1927) and A. Neumann during 1893-1894. Thymine s structure was published in 1900 and confirmed over the next several years when it was synthesized by several investigators. In 1903, cytosine was synthesized by Henry Lord Wheeler (1867-1914) and Treat B. Johnson, confirming its structure. Uracil was first isolated in 1900 from yeast nucleic acid found in bovine thymus and herring sperm. The methylation of uracil produces thymine thymine is also called 5-methyluracil because methylation takes place at the fifth carbon in uracil to produce thymine. 

Neuropeptides Y (NFY) and YY are 36-residue amidated peptides that are members of the pancreatic polypeptide (PP) family (Fig. 30-5). NPY is produced both in the peripheral nervous system and in the brain,110 134 where it is one of the most abundant neuropeptides. Another member of the PP family is semi-nalplasmin, a regulator of calcium ion transport in bovine sperm.135 NPY is best known for its stimulation of appetite. It also inhibits anxiety and increases memory retention. It has a vasoconstrictive effect on blood vessels, participating in cardiovascular regulation.136 137 Peptide YY is formed in endocrine cells of the intestine, while NPY is formed in neurons of the parasympathetic system.138 Both participate in regulation of fluid and electrolyte secretion. Both are found in other vertebrate species.139... 

Narasimhan et al.(39) have confirmed the very limited, if not negligible, capacity of sperm to synthesize SGG by incubating bovine spermatozoa with labelled glycerol and galactose. No radioactivity was detected in the SGG following incubation with these compounds. Radioactivity from these compounds was, however, found to be incorporated into SGG when they were injected into the testes of mature rats. 

In a cell manipulation experiment, a constriction together with two narrow channels ( 50 pm) at the corner of a large channel were fabricated on a PDMS chip (see Figure 8.12). This microfluidic method was devised to remove cumulus cells from individual bovine cumulus-oocyte complexes before in vitro fertilization. In natural fertilization, sperms release hyaluronidase that attack... 

MATERIALS. Ribonuclease A (RNase A) (bovine pancreas), cytochrome C (Cyt. C) (horse heart), lysozyme (chicken egg white), myoglobin (sperm whale), P-lactoglobulin A... 

Blots are prehybridized to block all nonspecific binding (which causes background). To do this, one first wets the nitrocellulose in 3 X SSC, then in 50% formamide, 3X SSC, 0.1% sodium dodecyl sulfate (SDS), 1 mM EDTA (pH 8.0), 10 mM Tris (pH 7.5), 10X Denhardt s solution [1X Denhardt s is 0.02% Ficoll, 0.02% bovine serum albumin (BSA), and 0.02% polyvinylpyrrolidone 360], 0.05% sodium pyrophosphate, and 100 /ig/ml denatured DNA. Denatured DNA is sheared herring or salmon sperm DNA that has been boiled for 10 min before addition to the prehybridization mix. Blots are sealed within plastic bags, placed between two glass plates to give uniform distribution of prehybridization solution over the blot, and incubated in a water bath at 37° for at least 1 hr. 

From some males in all groups and from those males which did not impregnate, a sperm sample is collected from an incised distal tubule in the cauda of one epididymis. The sample is suspended in a specially defined culture medium of a mixture of bovine serum albumin. The number of motionless, motile and progressively forward moving spermatozoa is then counted on a warmed microscopic slide or using an automatic counting system. Spermatological examination can also be conducted in males whose mated females showed an increased number of dead conceptuses. Additionally, the number of spermatozoa is counted from a part of the semen isolated from the opened cauda epididymis in a Thoma chamber. 

FIGURE 13 Plot of the logarithm of the retention volume (In VR) versus the concentration of the displacing salt, ammonium sulphate, in the HP-HIC mode with the proteins I, insulin B-chain 2, bovine trypsin inhibitor 3, bovine trypsinogen 4, insulin A-chain 5, ribonuclease 6, sperm whale myoglobin 7, horse heart cytochrome c. Data from Ref. 42. 

Gamer, D.L. et al. 1994. Dual DNA staining assessment of bovine sperm viability using SYBR-14 and pro-pidium iodide. J. Androl. 15, 620-629. 

Bovine serum albumin is often used as protein supplement in cell culture media, and residual bovine serum albumin in some formulations has occasionally caused adverse effects. Symptoms are usually mild, such as itching and urticaria. An anaphylactic reaction has been described in a patient undergoing bone marrow transplantation after the bone marrow cells had been kept in bovine serum albumin. As a component of sperm processing media, bovine serum albumin has caused adverse effects after intrauterine insemination (1). The risk of transmission of nvCJD by recombinant proteins is unknown, as cell cultures used for manufacturing them often contain bovine serum albumin (2). 

Table 6 Bovine sperm motility on various silicone rubber films swollen or embedded with pure N-9 or N-9-oc-CD-IC...

Cryoprotectants are added to the culture medium in order to protect cells. Glycerine, the first cryoprotectant to be used, was discovered in the 1940s, and it was used for the cryopreservation of bovine sperm. More recently, it has been discovered that other substances such as dimethyl sulfoxide (DMSO), saccharides," and proteins also function as cryoprotectants. However, the mechanism of the cryopreservation process in each case remains unclear. In the present study, we compared DMSO and trehalose, which are cryoprotectants of different molecular sizes that may differ in their ability to pass through the cell membrane. 

Bovine oocyte fertilization test Formation of female and male pronucleus after penetration of sperm into matured oocytes Hazard identification that could affect fertility... 

The bovine oocyte in vitro maturation assay (blVM) and the bovine oocyte in vitro fertilization assay (blVF) aim at the detection of adverse effects on the oocyte and the sperm during the processes... 

Another year went by, with still no results. The stress of timing sexual activity, results-oriented lovemaking, and the disappointment of constant failure began to create marital problems. Beginning to search for alternatives, they tried a nutritionist (vitamin E, zinc, raw bovine testicular tissue), a hypnotist (repeat after me, your sperm is getting lively ), and homeopathy, but nothing helped. After a third year of despair, they finally came to my office, saying I was their last hope. 

PA-PLAi, which is expressed in mature bovine testes but not in newborn calf testes, may contribute to the formation or function of sperm. PA-PLAi may also be involved in the remodebng of phospholipids by hydrolyzing fatty acids at the sn-1 position and by subsequent acylation that occurs at this position. 

Biomedical molecules are typically large molecular and weak polar materials, for which exfoHated graphite has a large sorption capacity. The sorption performance of exfoHated graphite with different bulk densities was studied on several kinds of biomedical molecules, ovalbumin, serum albumin, bovine serum albumin (BSA), lysine, and herring sperm DNA [19]. 

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