Vanadate increases oxygen affinity and affects enzyme activities and membrane properties of erythrocytes

Incubation of blood with vanadate markedly increases the affinity of hemoglobin for oxygen, decreases the deformability of erythrocytes, reduces their osmotic fragility and alters their morphology, determining the appearance of equinocytic forms. Since vanadate is easily taken up by the erythrocytes and binds hemoglobin, these effects might result from interactions of vanadate with hemoglobin and with membrane proteins at the glycerate-2, 3-P₂ and/or ATP binding site. In addition, vanadate inhibits phosphoglycerate mutase, phosphoglucomutase and adenylate-kinase activities from hemolysates, suggesting a possible inhibitory effect on erythrocyte metabolism     

Prognostic Role of Host Cyclooxygenase and Cytokine Genotypes in a Caucasian Cohort of Patients with Gastric Adenocarcinoma

Background

Genetic factors influencing the prognosis of gastric adenocarcinoma (GAC) are not well known. Given the relevance of cytokines and other pro-inflammatory mediators in cancer progression and invasiveness, we aimed to assess the prognostic role of several functional cytokine and cyclooxygenase gene polymorphisms in patients with GAC.

Methodology

Genomic DNA from 380 Spanish Caucasian patients with primary GAC was genotyped for 23 polymorphisms in pro-inflammatory (IL1B, TNFA, LTA, IL6, IL12p40), anti-inflammatory (IL4, IL1RN, IL10, TGFB1) cytokine, and cyclooxygenase (PTGS1 and PTGS2) genes by PCR, RFLP and TaqMan assays. Clinical and histological information was collected prospectively. Survival curves were estimated by the Kaplan-Meier method and compared using the log rank test. Outcome was determined by analysis of Cox proportional hazards, adjusting for confounding factors.

Results

The median follow-up period and median overall survival (OS) time were 9.9 months (range 0.4–120.3) and 10.9 months (95% CI: 8.9–14.1), respectively. Multivariate analysis identified tumor stages III (HR, 3.23; 95% CI:2–5.22) and IV (HR, 5.5; 95% CI: 3.51–8.63) as independent factors associated with a significantly reduced OS, whereas surgical treatment (HR: 0.44; 95%CI: 0.3–0.6) was related to a better prognosis of the disease. Concerning genetic factors, none of the 23 polymorphisms evaluated in the current study did influence survival. Moreover, no gene-environment interactions on GAC prognosis were observed.

Conclusions

Our results show that, in our population, the panel of selected pro- and anti-inflammatory cytokine, and cyclooxygenase gene polymorphisms are not relevant in determining the prognosis of gastric adenocarcinoma.     

Genetic diversity of different apricot geographical groups determined by SSR markers.

Forty apricot cultivars with different geographic origins belonging to the germplasm collections of St. Istvan University (Budapest, Hungary) and the Instituto Valenciano de Investigaciones Agrarias (IVIA) (Valencia, Spain) were studied by means of SSR markers. The aim of the study was to determine the genetic relationships among genotypes from different eco-geographical groups. Sixteen primer pairs flanking microsatellite sequences in the peach genome were assayed. Eleven of them were polymorphic in the set of cultivars studied and allowed every genotype to be unambiguously distinguished. Genetic diversity in the population studied was analyzed using several variability parameters. A total of 34 alleles were detected with a mean value of 3.1 alleles/locus. The expected heterozygosity mean was 0.46 and the observed heterozygosity was 32% on an average leading to a high value of the Wright's fixation index (0.32). Additionally, UPGMA cluster analysis based on Nei's genetic distance grouped genotypes according to their geographic origins and pedigrees. SSR markers have proved to be an efficient tool for fingerprinting cultivars and conducting genetic-diversity studies in apricot.     

Arg-Lys-Asp-Val-Tyr (thymopentin) accelerates the cholinergic-induced inactivation (desensitization) of reconstituted nicotinic receptor

1. The thymic hormone thymopoietin blocks neuromuscular transmission and was proposed (Goldstein, 1974) as a modulator of synaptic conductivity. 2. The cholinergic-induced inactivation of nicotinic receptor reconstituted into asolectin lipid vesicles was studied in the presence and in the absence of thymopentin, a synthetic pentapeptide corresponding to positions 32-36 of thymopoietin. 3. The present data show that thymopentin accelerates desensitization of the nicotinic acetylcholine receptor, supporting the aforementioned physiological role proposed for thymopoietin. 4. They also suggest that the hormone itself and/or a yet unidentified hormine-derived peptide fragment may act as an endogenous ligand for nicotinic acetylcholine receptor desensitization.