Effects of salinity on the growth and nutrient retention in silver perch, Bidyanus bidyanus (Mitchell 1838) (Teraponidae)

The silver perch, Bidyanus bidyanus, is a native Australian freshwater fish of the highest aquaculture potential. The species is known to tolerate a certain extent of salinity. Silver perch juveniles were fed a commercial diet (45% protein) and reared at salinities 0, 4, 8 and 12 in order to assess weight gain, specific growth rate (SGR), food conversion ratio (FCR) and nutrient retention at these four salinities. Fish reared at salinity 4 (P < 0.05) showed the best weight gain, SGR, FCR and a significantly better performance. Nitrogen and phosphorus retention were also significantly better in fish reared at salinity 4 (P < 0.05).     

Primary human epithelial cell culture system for studying interactions between female upper genital tract and sexually transmitted viruses, HSV-2 and HIV-1

Evidence from clinical and epidemiological studies indicates that women are disproportionately susceptible to sexually transmitted viral infections. To understand the underlying biological basis for this increased susceptibility, more studies are needed to examine the acute events in the female reproductive tract following exposure to viruses during sexual transmission. The epithelial lining of the female reproductive tract is the primary barrier that sexually transmitted viruses, such as HIV-1 and HSV-2 need to infect or traverse, in order to initiate and establish productive infection. We have established an ex-vivo primary culture system to grow genital epithelial cells from upper reproductive tract tissues of women. Using these cultures, we have extensively examined the interactions between epithelial cells of the female genital tract and HSV-2 and HIV-1. In this review, we describe in detail the experimental protocol to grow these cultures, monitor their differentiation and inoculate with HSV-2 and HIV-1. Prospective use of these cultures to re-create the microenvironment in the reproductive tract is discussed.     

Modulator effects of the methylenetetrahydrofolate reductase C677T polymorphism on response to vitamin B12 therapy and homocysteine metabolism

In this study, our aim was to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the vitamin B12 therapy response in 95 patients with vitamin B12 deficiency and 92 healthy control subjects using vitamin B12, plasma total homocysteine (tHcy), and folate as the main measure of outcome. MTHFR C677T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism techniques. There were no differences in the distribution of MTHFR genotypes in the cases versus the controls. Mean concentrations of plasma tHcy and B12 vitamin were 18.84 μM and 142.47 pg/mL in patients with TT (10.5%) genotypes. Furthermore, mean concentrations of B12 vitamin after cobalamin therapy were 697.62, 656.64, and 488.76 pg/mL in patients with the CC, CT, and TT genotypes, respectively. The MTHFR 677 TT genotype has decreasing effect in B12 vitamin and increasing effect in tHcy. In comparison with the patients having CC and CT genotypes, patients with the TT genotype had a lower response to vitamin B12 therapy.     

Protein kinase A-mediated CREB phosphorylation is an oxidant-induced survival pathway in alveolar type II cells

Oxidant stress plays a role in the pathogenesis of pulmonary diseases, including fibrotic lung disease and cancer. We previously found that hydrogen peroxide (H₂O₂) initiates an increase in Ca²⁺/cAMP-response element binding protein (CREB) phosphorylation in C10 alveolar type II cells that requires activation of extracellular regulated kinases 1/2 (ERK1/2). Here, we investigated the role of crosstalk between protein kinase A (PKA) and epidermal growth factor receptor (EGFR) in oxidant-induced signaling to ERK1/2 and CREB in C10 cells. Application of H₂O₂ increased nuclear accumulation of PKA, and inhibition of PKA with H89 reduced oxidant-mediated phosphorylation of both CREB and ERK1/2. Single cell measurements of cAMP and redox status, using a FRET-based biosensor and a redox-sensitive GFP, respectively, indicated that H₂O₂ increases production of cAMP that correlates with redox state. Inhibition of EGFR activity decreased both H₂O₂-induced CREB phosphorylation and translocation of PKA to the nucleus, suggesting that crosstalk between PKA and EGFR underlies the oxidant-induced CREB response. Furthermore, knockdown of CREB expression using siRNA led to a decrease in bcl-2 and an increase in oxidant-induced apoptosis. Together these data reveal a novel role for crosstalk between PKA, ERK1/2 and CREB that mediates cell survival during oxidant stress.     

Genetic determinants of phenotypic diversity in humans

New technologies for rapidly assaying DNA sequences have revealed that the degree and nature of human genetic variation is far more complex then previously realized. These same technologies have also resulted in the identification of common genetic variants associated with more than 30 human diseases and traits.     

The European Bioinformatics Institute web site: a new view

SUMMARY: The European Bioinformatics Institute (EBI), and outstation of the European Molecular Biology laboratory, has revamped its web site for the second time since 1997 in order to address increased user demand as well as establishing better uniformity and easier accessibility for the ever growing number of users and services it offers to the community. A GRID-like hardware infrastructure has been put in place to provide round the clock services in a redundant and reliable fashion. AVAILABILITY: http://www.ebi.ac.uk/     

Mutations in the Glycosyltransferase Domain of GLT8D1 Are Associated with Familial Amyotrophic Lateral Sclerosis

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Protease production by free and immobilized cells of the cold-adapted yeast Cryptococcus victoriae CA-8

The present study was performed to produce the protease using free and immobilized cells of locally isolated cold-adapted psychrotolerant yeast Cryptococcus victoriae CA-8. Cell immobilization was performed using sodium alginate as entrapping agent. The best conditions for enzyme production by both free and immobilized cells of the yeast were temperature of 15°C and initial pH of 8.0. The optimal incubation times were 72 and 96 h for immobilized and free cells, respectively. Immobilized cells were reused in 3 successive reaction cycles without any loss in the maximum protease activity. Little decreases in the protease activity were observed in 4 and 5 cycles. Under the optimized conditions, the maximum enzyme activities were determined as 12.1 and 13.5 U/mL for free and immobilized cells, respectively. This is a first attempt on cold-active alkaline protease production by free and/or immobilized cells of yeasts. Besides, the protease activity of the yeast C. victoriae CA-8 was investigated for the first time in the present study.