T5 Group Bacteriophages as Potential Phage Therapy Agents

Microbiology - The T5 group bacteriophages, which infect a number of enterobacterial species and strains, are useful objects for obtaining therapeutic phage preparations with broad specificity. The...     

Cancer-testis gene expression profile in human melanoma cell lines

A growing number of evidence indicates that cancer-testis antigens (CTA) can be used as specific targets for immune therapy of malignant melanoma. The aim of this study was to provide a basis for selecting the most suitable CTA by analyzing the mRNA expression profile of genes encoding CTA in melanoma cell lines. We used a real-time quantitative PCR to measure the expression level for the following genes: GAGE1, NY-ESO-1, MAGEA1, PASD, SCP1, SEMG1, SPANXA, SSX1, and PRAME. The objects of study were cell lines mel P, mel Si, mel Mtp, mel Il, mel Hn, mel Ibr, and mel Kor obtained from patients diagnosed with disseminated melanoma. We established that the highest frequency of occurrence and the highest expression level had the following genes: GAGE1, NY-ESO-1, MAGEA1, SCP1, SPANXA, SSX1, and PRAME. Their mRNA translation products can be promising candidates for immunotherapy.     

The genetic basis of alcoholism: multiple phenotypes,many genes,complex networks

Alcoholism is a significant public health problem. A picture of the genetic architecture underlying alcohol-related phenotypes is emerging from genome-wide association studies and work on genetically tractable model organisms.     

Micellar laccase-catalyzed synthesis of electroconductive polyaniline

A method of enzymatic synthesis of electroconductive polyaniline on the micelles of dodecylbenzenesulfonic acid sodium salt (DBSNa) is proposed. The high potential laccase from the basidiomycete Trametes hirsuta was used as a biocatalyst. The conditions for polyaniline synthesis were optimized (pH 4.0; reagent concentrations, 10–20 mM; and aniline/DBSNa ratio, 2 : 1). The resulting product was electrochemically active in the range of potentials from ?200 to 600 mV, electroconductive, and capable of reversible dedoping with a change in pH of solution.     

Peculiarities of leukotrienes metabolism in vitamin E deficiency in rats

Some changes take place in the spectrum of fatty acid, cholesterol and individual phospholipids' composition in the rat liver, under E-hypovitaminosis, that can play a considerable role in the cell damage. The level of cysteinyl leucotriene decreases in the blood and liver under E-hypovitaminosis and it rises to the control level under vitamin E correction. This demonstrates the influence of tocopherol on 5-LO pathway arachidonic acid.     

Monitoring of phytoplankton in the area of a sea farm in Vostok Bay (Sea of Japan)

The qualitative and quantitative composition of phytoplankton in the area of a sea farm in Vostok Bay (Sea of Japan) was investigated from July 2001 to May 2002. The overall numbers of phytoplankton were 0.008 to 5.3 million cells/liter, and the biomass was 0.02 to 20.5 g/m³. The maximum density and biomass of phytoplankton were observed in summer, fall, and winter. Ten species known to be toxic were recorded. Of these, Pseudo-nitzschia multiseries (Hasle) Hasle, Alexandrium acatenella (Whedon et Kofoid) Balech, and Chattonella marina (Subrahmanyan) Hara et Chihara were found in Vostok Bay for the first time. For the diatom Skeletonema costatum (Greville) Cleve, which is an indicator of extremely eutrophic waters, the cell density was positively correlated with the area of the culture site.Original Russian Text Copyright © 2005 by Biologiya Morya, Morozova, Orlova.     

Structure-function aspects of PstS in multi-drug-resistant Pseudomonas aeruginosa

The increasing prevalence of multi-drug-resistant (MDR) strains of Pseudomonas aeruginosa among critically ill humans is of significant concern. In the current study, we show that MDR clinical isolates of P. aeruginosa representing three distinct genotypes that display high virulence against intestinal epithelial cells, form novel appendage-like structures on their cell surfaces. These appendages contain PstS, an extracellular phosphate binding protein. Using anti-PstS antibodies, we determined that the PstS-rich appendages in MDR strains are involved in adherence to and disruption of the integrity of cultured intestinal epithelial cell monolayers. The outer surface-expressed PstS protein was also identified to be present in P. aeruginosa MPAO1, although to a lesser degree, and its role in conferring an adhesive and barrier disruptive phenotype against intestinal epithelial cells was confirmed using an isogenic DeltaPstS mutant. Formation of the PstS rich appendages was induced during phosphate limitation and completely suppressed in phosphate-rich media. Injection of MDR strains directly into the intestinal tract of surgically injured mice, a known model of phosphate limitation, caused high mortality rates (60%-100%). Repletion of intestinal phosphate in this model completely prevented mortality. Finally, significantly less outer surface PstS was observed in the MPAO1 mutant DeltaHxcR thus establishing a role for the alternative type II secretion system Hxc in outer surface PstS expression. Gene expression analysis performed by RT-PCR confirmed this finding and further demonstrated abundant expression of pstS analogous to pa5369, pstS analogous to pa0688/pa14-55410, and hxcX in MDR strains. Taken together, these studies provide evidence that outer surface PstS expression confers a highly virulent phenotype of MDR isolates against the intestinal epithelium that alters their adhesive and barrier disrupting properties against the intestinal epithelium.     

Antitumor immunotherapy with the use of synthetic fragments of survivin

The endogenous protein survivin is present in tumor cells and inhibits apoptosis. The influence of vaccination of mice by survivin fragments on growth of various types of tumors was studied in order to examine the possibility of creation of an antitumor vaccinating agent on its basis. Two peptides corresponding to the 118–144 and (80–88)-(153–165) sequences of survivin 2B were chosen and synthesized on the basis of literature data and theoretical calculations. Their ability to stimulate antibody production in mice of the C57BL/6J line (b-haplotype) and in BDF1 hybrids (b × d-haplotype) was investigated. Both peptides were shown to stimulate production of antibodies that bound the recombinant survivin in the BDF1 mice. Immunization of BDF1 and C57BL/6J mice with the recombinant survivin resulted in formation of antibodies that reacted with 118–144 peptide. The effect of preventive vaccination with the peptides and the recombinant protein on dynamics of growth of several species of tumors was studied. Vaccination with the (80–88)-(153–165) peptide was found to cause an antitumor effect in BDF1 mice suffered from sarcoma S-37. Thus, creation of antitumor agent on the basis of this peptide is a promising area of further studies.     

Effect of Plant Oligoadenylates on Viral Infection and Antistress and Growth-Regulating Properties in Potato Plants Grown in vitro

Biological properties of plant oligoadenylates (POA) were studied in in vitro grown potato (Solanum tuberosum L.) plants. POA were synthesized by ATP polymerization in the presence of an enzyme preparation isolated from leaves of wild potato Solanum chacoense Bitt. treated with resistance inducers. The concentration of viral antigen was determined by the method of immunoenzyme analysis. In the course of virus elimination by the apical meristem method, pretreatment of potato tuber sprouts with POA increased the survival rate of meristem explants and, in several cultivars, enhanced morphogenesis and increased the yield of virus-free regenerants. Prolonged application of POA in the nutrient medium for microcutting of potato tube plants infected in vitro with X-, S-, and M-viruses increased their height due to internode lengthening. The effect of this treatment on virus reproduction was ambiguous: various combinations of virus species, the duration of growth on POA-containing media, and POA concentration resulted in either statistically significant inhibition or a significant enhancement of virus reproduction. Possible mechanisms of the antistress effect of POA, in connection with their effect on virus reproduction, are discussed.