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The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (

Summary The African buffalo (Syncerus caffer) has been implicated as the reservoir of several bovine infectious agents. However, there is insufficient information on the protective immune responses in the African buffalo, particularly in infected animals. In this study, we analysed Th1 cytokines IL-2 and IFN-γ, and Th2 cytokines IL-4 and IL-10. The cloned cDNA of IL-2, IL-4, IL-10 and IFN-γ contained an open reading frame of 468, 501, 408 and 540 nucleotides, encoding polypeptides of 155, 166, 135 and 179 amino acids, respectively. Nucleotide sequence homology of IL-2, IFN-γ and IL-4 was more than 98% between the African buffalo and cattle, which resulted in identical polypeptides. Meanwhile, IL-10 gene of African buffalo and cattle had 95% homology in nucleotide sequence, corresponding to thirteen amino acid residues substitution. Cysteine residues and potential glycosylation sites were conserved within the family Bovinae. Phylogenetic analyses including cytokines of the African buffalo placed them within a cluster comprised mainly of species belonging to the order Artiodactyla, including cattle, water buffalo, sheep, goat, pig and artiodactyl wildlife. A deeper understanding of the structure of these cytokines will shed light on their protective role in the disease-resistant African buffalo in comparison with other closely related species.

It is now clearly established that steroids can be synthesized de novo by the brain and the peripheral nervous systems. Such steroids are called neurosteroids, and de novo neurosteroidogenesis from cholesterol is a conserved property of vertebrate brains. Our studies over the past decade have demonstrated that the brain expresses several kinds of steroidogenic enzymes and produces a variety of neurosteroids in submammalian species. However, the biosynthetic pathway of neurosteroids in nonmammalian vertebrates as well as in mammals may be still incompletely mapped out. We recently found that the brain of newts and quail actively produces 7alpha-hydroxypregnenolone, a novel bioactive neurosteroid, from pregnenolone. Interestingly, 7alpha-hydroxypregnenolone stimulates locomotor activity by means of the dopaminergic system. Subsequently, we demonstrated that melatonin regulates synthesis of 7alpha-hydroxypregnenolone, a key factor for induction of locomotor activity, thus inducing diurnal locomotor changes.

The activation of tumor suppressor p53 induces apoptosis or cell cycle arrest depending on the state and type of cell, but it is not fully understood how these different responses are regulated. Here, we show that Puma and Noxa, the well-known p53-inducible proapoptotic members of the Bcl-2 family, differentially participate in dual pathways of the induction of apoptosis. In normal cells, Puma but not Noxa induces mitochondrial outer membrane permeabilization (MOMP), and this function is mediated in part by a pathway that involves calcium release from the endoplasmic reticulum (ER) and the subsequent caspase activation. However, upon E1A oncoprotein expression, cells also become susceptible to MOMP induction by Noxa, owing to their sensitization to the ER-independent pathway. These findings offer a new insight into differential cellular responses induced by p53, and may have therapeutic implications in cancer.

The palladium-catalyzed synthesis of unsymmetrical 1,3-diarylpropenes from allyl esters through a Mizoroki–Heck-type reaction with aryl iodides followed by allyl cross-coupling with a variety of arylboronic acids was developed; the products are obtained in moderate to good yields by using a hydrazone–Pd(OAc)2 system.

In the present study, we monitored Foxp3(+) T cells in bovine leukemia virus (BLV)-infected cattle. By flow cytometric analysis, the proportion of Foxp3(+) CD4(+) cells from persistent lymphocytotic cattle was significantly increased compared to control and AL cattle. Interestingly, the proportion of Foxp3(+) CD4(+) cells correlated positively with the increased number of lymphocytes, virus titer and virus load, whereas it inversely correlated with IFN-γ mRNA expression, suggesting that Foxp3(+) CD4(+) T cells in cattle have a potentially immunosuppressive function. Further studies are necessary to elucidate the detailed mechanism behind the increased Treg during BLV infection.

The method renders possible the access to various unsymmetrical target compounds as exclusive (E)-isomers.

CuI as co-catalyst and hydrazone BIH as the ligand render possible the preparation of various diarylalkynes in the presence of low amounts of Pd catalyst.

A class of π-conjugated 2,5-bis(benzoazol-2-yl)pyrazine dyes have been synthesized in which 2,5-bis(benzimidazol-2-yl)pyrazine (1) exhibits strong fluorescence in solution. The enhanced fluorescence of 1 with a base leads to future applications such as anion sensing feasible upon chemical modification.