Functional redundancies, generated by gene duplications, are highly widespread throughout all known genomes. One consequence of these redundancies is a tremendous increase to the robustness of organisms to mutations and other stresses. Yet, this very robustness also renders redundancy evolutionarily unstable, and it is, thus, predicted to have only a transient lifetime. In contrast, numerous re...

Helicobacter pylori arginase, a bimetallic enzyme, is crucial for pathogenesis of the bacterium in human stomach. Despite conservation of the signature motifs in all arginases, the H. pylori homolog has a non-conserved motif (153ESEEKAWQKLCSL165), whose role was recently shown to be critical for its stability and function. The sequence analysis also reveals the presence of this motif with criti...

To date, the only repeatable method to select spermatozoa for chromosomal sex is the Beltsville sorting technology using flow cytometry. Improvement of this technology in the equine species requires increasing awareness of the modifications that the sorting procedure induces on sperm intactness. Oxidative stress is regarded as the major damaging phenomenon, and increasing evidence regards handl...

This study aimed to evaluate the effect of the exogenous recombinant bovine somatotropin (rbST) on plasma concentrations of insulin-like growth factor I (IGF-I), insulin and semen quality of bulls. Twenty bulls (Aberdeen Angus and Brangus) were divided by breed into two groups. Placebo group was injected with NaCl 0.9% (s.c.) and treatment group with rbST (s.c., 500 mg) at days 0 and 14 of the ...

Chronic iron overload has slow and insidious effects on heart, liver, and other organs. Because iron-driven oxidation of most biologic materials (such as lipids and proteins) is readily repaired, this slow progression of organ damage implies some kind of biological "memory." We hypothesized that cumulative iron-catalyzed oxidant damage to mtDNA might occur in iron overload, perhaps explaining t...

Ocular films of pefloxacin mesylate were prepared with the objectives of reducing the frequency of administration, to improve patient compliance, obtaining controlled release and greater therapeutic efficacy in the treatment of eye infections such as conjunctivitis, keratitis, kerato conjunctivitis, corneal ulcers etc. Polymers such as HPC, HPMC, PVP and PVA were used in different ratios to pre...

Procedures for the preparation of soluble collagen from rat skin and tail tendon were reviewed and revised to permit the preparation of native monomeric collagen with intact nonhelical ends. The degree of intactness was estimated from the tyrosine content, which is present only in the nonhelical ends, and by mobility of the COOH-terminal cyanogen bromide peptide of the alpha1 chain on sodium do...

Hyperthermophilic superoxide dismutases (SODs) are of particular interest due to their potential industrial importance and scientific merit in studying the molecular mechanisms of protein folding and stability. Compared to the mesophilic SODs, the hyperthermostable Fe-SODs (TcSOD and ApSOD) have an extended C-terminal helix, which forms an additional ion-pairing network. In this research, the r...

Despite its use for a long time, the way thalamic ventrobasal (VB) stimulation acts to produce pain relief is still unknown. One of the most accepted hypotheses, sponsored by Tsubokawa among others, proposes that VB stimulation excites raphespinal and reticulospinal neurons of the rostroventral medulla which in turn send respectively inhibitory serotonergic and noradrenergic axons through both ...

recent technological improvements have extended the application range of dielectric permittivity biomass measurements to on-line monitoring of physiological changes during bacterial fermentations. in an industrial fermentation of bacillus thuringiensis, it is important to verify the intactness of bacterial plasmid content in all steps of culture. changes in certain plasmid resident properties o...