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Background: Specific coping styles have been shown to modulate stress-induced immune alterations and influence actual health outcomes. This study examined the effects of stressors and coping styles on human T-cell subpopulations and in vitro cytokine production using a cross-sectional design. Methods: Seventy-one men (18–60 years old) were asked to complete a self-administered questionnaire that evaluates quantitative workload, mental demand and coping styles. The numbers of T-cell subpopulations and concentrations of interferon-γ (IFN-γ) and interleukin-4 (IL-4) after stimulation with phytohemaglutinin were measured. Results: Positive and negative coping were negatively related to IL-4 and the number of CD4+ cells, respectively. Interactions between positive coping and mental demand significantly affected the number of CD8+ cells, IFN-γ, IL-4 and the IFN-γ/IL-4 ratio. Among men reporting high mental demand, positive coping was related to increased IFN-γ and IFN-γ/IL-4. Among men reporting low mental demand, positive coping was related to a decreased number of CD8+ cells and lower concentrations of IFN-γ and IL-4. Analyses adjusting for the numbers of CD3+ and CD8+ cells revealed that the interactive effects of positive coping and mental demand on cytokine levels were attributable to the changes in T-cell function rather than the number of T cells. No modulating effect of anxiety on the associations of stressors and coping with immune function was observed. Depressive symptoms slightly, though not significantly, modulated the association of negative coping and the number of CD4+ cells. Conclusions: From the perspective of immunology, optimal stress characteristics were determined by an individual’s coping styles, with positive coping being associated with stress-induced changes in the number of CD8+ cells and in vitro cytokine production from T cells. Our findings suggest that it is important to consider the interactive effects of the complexity of work and the individual coping style in stress management.Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The only species of the genus Triopsin Australia, T. australiensis, is found to reproduce by gonochorism. Morphological and reproductive data and molecular analyses of fragments of mitochondrial genes 12S rRNA (12S) and cytochrome oxidase I (COI) indicate that a Triopspopulation from the middle Paroo in north-western New South Wales is composed of two different entities, Triopscf. australiensislineage A, and T. cf. australiensislineage B. Gonad histology in individuals with ovisacs of lineage A revealed no evidence of testicular tissue; however, large testicular lobes were found in individuals with ovisacs of lineage B, indicating that they were anatomically hermaphrodites. This is the first record of Australian hermaphroditic Triops. For each lineage, a single haplotype of each gene was obtained. Molecular genetic distance and phylogenetic analyses confirmed the closer relationship and monophyly of the two lineages with T. australiensis(GenBank) when compared with Triopsspecies from other continents. COI haplotypes of lineage A and lineage B differed by 7.7% from each other and differed by 10.2% and 9.6% from a published T. australiensissequence, respectively. The 12S haplotypes of lineage A and lineage B differed by 3.3% from each other and differed by 2% and 2.5% from a published T. australiensissequence, respectively. Our results suggest that the two co-occurring Triopslineages probably represent two species that are distinct from T. australiensis. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine the antibacterial activity of oolong tea extract on oral streptococci, including Streptococcus mutans and Streptococcus sobrinus, and to identify the response to its components. Antibacterial activity was found when the extract was added to S. mutans cells in chemically defined medium but not in complex broth media. Further, pretreatment with bovine serum albumin reduced the antibacterial activity. The extract showed antibacterial activity against all of the oral streptococci examined, with the highest activity against S. mutans MT8148R. This activity was found to originate from a monomeric polyphenol-rich fraction, and it was stronger than that of pure polyphenols. Moreover, some combinations of monomeric polyphenols showed the highest level of antibacterial activity. These results suggest that the antibacterial activity of oolong tea extract is caused by a synergistic effect of monomeric polyphenols, which can easily bind to proteins.Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]