Atrial Natriuretic Peptide Gene Polymorphisms and Risk of Ischemic Stroke in Humans

Background and Purpose— A precise definition of genetic factors responsible for common forms of stroke is still lacking. The purpose of the present study was to investigate the contributory role of the genes encoding atrial natriuretic peptide ( ANP ) and type A natriuretic peptide receptor ( NPRA ) in humans' susceptibility to develop ischemic stroke. Methods— Allele and genotype frequencies of ANP and NPRA were characterized in an Italian case-control study with patients affected by vascular disease or risk factors. Subjects were recruited from the island of Sardinia (206 cases, 236 controls). Results— A significant association between the ANP /TC2238 polymorphic site and stroke occurrence was found when a recessive model of inheritance was assumed. The risk conferred by this mutant genotype, when estimated by multivariate logistic regression analysis, was 3.8 (95% confidence interval, 1.4 to 10.9). A significantly increased risk of stroke recurrence was observed among cases carrying the ANP /CC2238 genotype compared with cases carrying the ANP /TT2238 genotype ( P =0.04). No direct association of NPRA with stroke occurrence was detected. However, a significant epistatic interaction between the ANP /CC2238 genotype and an allelic variant of NPRA led to a 5.5-fold increased risk of stroke (95% confidence interval, 1.5 to 19.4). Conclusions— Our findings support a direct contributory role of ANP to stroke in humans. A significant interaction between ANP and NPRA on stroke occurrence was found

Infection of human T lymphoid cells by human herpesvirus 6 is blocked by two unrelated protein tyrosine kinase inhibitors, biochanin A and herbimycin

Human herpesvirus 6 is a T lymphotropic herpesvirus that causes exanthem subitum in infants and is considered a potential cofactor in AIDS etiopathogenesis and progression owing to its in vivo and in vitro interactions with human immunodeficiency virus, We report that no differences in phosphorylation on tyrosine residues of cellular proteins were detectable at early times following HHV-6 infection in comparison to uninfected cells, On the contrary, several cellular proteins appeared phosphorylated on tyrosine at 24-48 hr postinfection, In addition, when tyrosine phosphorylation induced by HHV-6 infection was inhibited by the tyrosine kinase inhibitor biochanin A, the infection of HSB-2 cells was also coordinately reduced, as judged by inhibition of cytopathic effect and by inhibition of early and late viral antigen expression, Similar results were obtained with a second unrelated tyrosine kinase inhibitor, herbimycin, The inhibitors seem to act at a late stage of the viral infectious cycle, since neither viral binding nor internalization were affected. Thus, our results indicate that HHV-6 infection leads to the phosphorylation of protein tyrosine kinases, which may play a role in the course of viral infection, probably by participating in the cytopathic effect induced by the virus

Customer-to-customer interactions: Broadening the scope of word of mouth research

The increasing emphasis on understanding the antecedents and consequences of customer-to-customer (C2C) interactions is one of the essential developments of customer management in recent years. This interest is driven much by new online environments that enable customers to be connected in numerous new ways and also supply researchers' access to rich C2C data. These developments present an opportunity and a challenge for firms and researchers who need to identify the aspects of C2C research on which to focus, as well as develop research methods that take advantage of these new data. The aim here is to take a broad view of C2C interactions and their effects and to highlight areas of significant research interest in this domain. The authors look at four main areas: the different dimensions of C2C interactions; social system issues related to individuals and to online communities; C2C context issues including product, channel, relational and market characteristics; and the identification, modeling, and assessment of business outcomes of C2C interactions. © The Author(s) 2010