The ameliorative effects of vinpocetine on apoptosis and HSP-70 expression in testicular torsion in rats

Vinpocetine is a potent antioxidant and free radical scavenger. We investigated the effects of vinpocetine on torsion/detorsion (T/D) induced testicular damage, HSP-70 expression and germ cell apoptosis in rats. Sixty Wistar albino adult male rats were divided into five groups of 12. The groups comprised a control group, a sham treated group, a T/D group, a vinpocetine treated group, and a T/D plus vinpocetine treated group. The left testis of each rat was subjected to unilateral torsion followed by detorsion after 2 h. Vinpocetine was administered intraperitoneally immediately and for 10 days following detorsion. At the end of the study, the rats were sacrificed and their testes removed and processed. HSP-70 expression, apoptosis and histopathological damage scores were determined for each group. Testicular T/D caused significant increases in apoptosis and HSP-70 expression, and a significant decrease in Johnsen’s testicular biopsy scores and mean seminiferous tubule diameter. Vinpocetine ameliorated testicular histopathology and HSP-70 expression in the T/D + vinpocetine group. Consequently, vinpocetine may prevent testicular injury following testicular torsion owing to its antioxidant effects.     

Antioxidant effect of carnosine treatment on renal oxidative stress in streptozotocin-induced diabetic rats

Nitric oxide (NO) plays a significant role in the development of diabetic nephropathy. We investigated the effects of an antioxidant, carnosine, on streptozotocin (STZ)-induced renal injury in diabetic rats. We used four groups of eight rats: group 1, control; group 2, carnosine treated; group 3, untreated diabetic; group 4, carnosine treated diabetic. Kidneys were removed and processed, and sections were stained with periodic acid-Schiff (PAS) and subjected to eNOS immunohistochemistry. Examination by light microscopy revealed degenerated glomeruli, thickened basement membrane and glycogen accumulation in the tubules of diabetic kidneys. Carnosine treatment prevented the renal morphological damage caused by diabetes. Moreover, administration of carnosine decreased somewhat the oxidative damage of diabetic nephropathy. Appropriate doses of carnosine might be a useful therapeutic option to reduce oxidative stress and associated renal injury in diabetes mellitus.     

The art of strain improvement of industrial lactic acid bacteria without the use of recombinant DNA technology

The food industry is constantly striving to develop new products to fulfil the ever changing demands of consumers and the strict requirements of regulatory agencies. For foods based on microbial fermentation, this pushes the boundaries of microbial performance and requires the constant development of new starter cultures with novel properties. Since the use of ingredients in the food industry is tightly regulated and under close scrutiny by consumers, the use of recombinant DNA technology to improve microbial performance is currently not an option. As a result, the focus for improving strains for microbial fermentation is on classical strain improvement methods. Here we review the use of these techniques to improve the functionality of lactic acid bacteria starter cultures for application in industrial-scale food production. Methods will be described for improving the bacteriophage resistance of specific strains, improving their texture forming ability, increasing their tolerance to stress and modulating both the amount and identity of acids produced during fermentation. In addition, approaches to eliminating undesirable properties will be described. Techniques include random mutagenesis, directed evolution and dominant selection schemes.     

Topochemical distribution of lignin and hydroxycinnamic acids in sugar-cane cell walls and its correlation with the enzymatic hydrolysis of polysaccharides

Background  

Lignin and hemicelluloses are the major components limiting enzyme infiltration into cell walls. Determination of the topochemical distribution of lignin and aromatics in sugar cane might provide important data on the recalcitrance of specific cells. We used cellular ultraviolet (UV) microspectrophotometry (UMSP) to topochemically detect lignin and hydroxycinnamic acids in individual fiber, vessel and parenchyma cell walls of untreated and chlorite-treated sugar cane. Internodes, presenting typical vascular bundles and sucrose-storing parenchyma cells, were divided into rind and pith fractions.     

B30.2-like domain proteins: update and new insights into a rapidly expanding family of proteins

The B30.2 domain is a conserved region of around 170 amino acids associated with several different protein domains, including the immunoglobulin folds of butyrophilin and the RING finger domain of ret finger protein. We recently reported several novel members of this family as well as previously undescribed protein families possessing the B30.2 domain. Many proteins have subsequently been found to possess this domain, including pyrin/marenostrin and the midline 1 (MID1) protein. Mutations in the B30.2 domain of pyrin/marenostrin are implicated in familial Mediterranean fever, and partial loss of the B30.2 domain of MID1 is responsible for Opitz G/BBB syndrome, characterized by developmental midline defects. In this study, we scrutinized the available sequence data bases for the identification of novel B30.2 domain proteins using highly sensitive database-searching tools. In addition, we discuss the chromosomal localization of genes in the B30.2 family, since the encoded proteins are likely to be involved in other forms of periodic fever, autoimmune, and genetic diseases.      

Out of Africa and back again: nested cladistic analysis of human Y chromosome variation

We surveyed nine diallelic polymorphic sites on the Y chromosomes of 1,544 individuals from Africa, Asia, Europe, Oceania, and the New World. Phylogenetic analyses of these nine sites resulted in a tree for 10 distinct Y haplotypes with a coalescence time of approximately 150,000 years. The 10 haplotypes were unevenly distributed among human populations: 5 were restricted to a particular continent, 2 were shared between Africa and Europe, 1 was present only in the Old World, and 2 were found in all geographic regions surveyed. The ancestral haplotype was limited to African populations. Random permutation procedures revealed statistically significant patterns of geographical structuring of this paternal genetic variation. The results of a nested cladistic analysis indicated that these geographical associations arose through a combination of processes, including restricted, recurrent gene flow (isolation by distance) and range expansions. We inferred that one of the oldest events in the nested cladistic analysis was a range expansion out of Africa which resulted in the complete replacement of Y chromosomes throughout the Old World, a finding consistent with many versions of the Out of Africa Replacement Model. A second and more recent range expansion brought Asian Y chromosomes back to Africa without replacing the indigenous African male gene pool. Thus, the previously observed high levels of Y chromosomal genetic diversity in Africa may be due in part to bidirectional population movements. Finally, a comparison of our results with those from nested cladistic analyses of human mtDNA and beta-globin data revealed different patterns of inferences for males and females concerning the relative roles of population history (range expansions) and population structure (recurrent gene flow), thereby adding a new sex-specific component to models of human evolution.      

Isomaltulose production using free cells: optimisation of a culture medium containing agricultural wastes and conversion in repeated-batch processes

The enzyme glucosyltransferase is an industrially important enzyme since it produces non-cariogenic isomaltulose (6-O-alpha-D-glucopyronosyl-1-6-D-fructofuranose) from sucrose by intramolecular transglucosylation. The experimental designs and response surface methodology (RSM) were applied for the optimisation of the nutrient concentrations in the culture medium for the production of glucosyltransferase by Erwinia sp. D12 in shaken flasks at 200 rpm and 30 degrees C. A statistical analysis of the results showed that, in the range studied, the factors had a significant effect (P < 0.05) on glucosyltransferase production and the highest enzyme activity (10.84 U/ml) was observed in culture medium containing sugar cane molasses (150 g l(-1)), corn steep liquor (20 g l(-1)), yeast extract Prodex Lac SD (15 g l(-1)) and K2HPO4 (0.5 g l(-1)) after 8 h at 30 degrees C. The production of cell biomass by the strain of Erwinia sp. D12 was carried out in a 6.6-l fermenter with a mixing rate of 200 rpm and an aeration rate of 1 vvm. Fermentation time, cellular growth, medium pH and glucosyltransferase production were observed. The greatest glucosyltransferase activity was 22.49 U/ml, obtained after 8 h of fermentation. The isomaltulose production from sucrose was performed using free Erwinia sp. D12 cells in a batch process using an orbital shaker. The influence of the parameters sucrose concentration, temperature, pH, and cell concentration on the conversion of sucrose into isomaltulose was studied. The free cells showed a high conversion rate of sucrose into isomaltulose using batch fermentation, obtaining an isomaltulose yield of 72.11% from sucrose solution 35% at 35 degrees C.     

Development of cell surface saccharides on embryonic pancreatic cells

Using a battery of seven lectin-ferritin conjugates as probes for cell surface glycoconjugates, we have studied the pattern of plasmalemmal differentiation of cells in the embryonic rat pancreas from day 15 in utero to the early postpartum stage. Our results indicate that differentiation of plasmalemmal glycoconjugates on acinar, endocrine, and centroacinar cells is temporally correlated with development and is unique for each cell type, as indicated by lectin-ferritin binding. Specifically, (a) expression of adult cell surface saccharide phenotype can be detected on presumptive acinar cells as early as 15 d in utero, as indicated by soybean agglutinin binding, and precedes development of intracellular organelles characteristic of mature acinar cells; (b) maturation of the plasmalemma of acinar cells is reached after intracellular cytodifferentiation is completed, as indicated by appearance of Con A and fucoselectin binding sites only at day 19 of development; conversely, maturation of the endocrine cell plasmalemma is accompanied by "loss" (masking) of ricinus communis II agglutinin receptors; and (c) binding sites for fucose lectins and for soybean agglutinin are absent on endocrine and centroacinar cells at all stages examined. We conclude that acinar, centroacinar, and endocrine cells develop from a common progenitor cell(s) whose plasmalemmal carbohydrate composition resembles most closely that of the adult centroacinar cell. Finally, appearance of acinar lumina beginning at approximately 17 d in utero is accompanied by differenetiation of apical and basolateral plasmalemmal domains of epithelial cells, as indicated by enhanced binding of several lectin-ferritin conjugates to the apical plasmalemmal, a pattern that persists from this stage through adult life.     

Identification of 491 proteins in the tear fluid proteome reveals a large number of proteases and protease inhibitors

Background  

The tear film is a thin layer of fluid that covers the ocular surface and is involved in lubrication and protection of the eye. Little is known about the protein composition of tear fluid but its deregulation is associated with disease states, such as diabetic dry eyes. This makes this body fluid an interesting candidate for in-depth proteomic analysis.