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Subtle Impact (subtle + impact)
Selected AbstractsSibling rivalry: competition between Pol X family members in V(D)J recombination and general double strand break repairIMMUNOLOGICAL REVIEWS, Issue 1 2004Stephanie A. Nick McElhinny Summary:, The nonhomologous end-joining pathway is a major means for repairing double-strand breaks (DSBs) in all mitotic cell types. This repair pathway is also the only efficient means for resolving DSB intermediates in V(D)J recombination, a lymphocyte-specific genome rearrangement required for assembly of antigen receptors. A role for polymerases in end-joining has been well established. They are a major factor in determining the character of repair junctions but, in contrast to ,core' end-joining factors, typically appear to have a subtle impact on the efficiency of end-joining. Recent work implicates several members of the Pol X family in end-joining and suggests surprising complexity in the control of how these different polymerases are employed in this pathway. [source] Immune escape and exploitation strategies of cytomegaloviruses: impact on and imitation of the major histocompatibility systemCELLULAR MICROBIOLOGY, Issue 8 2004Edward S. Mocarski Jr Summary Cytomegalovirus (CMV) has yielded many insights into immune escape mechanisms. Both human and mouse CMV encode a diverse array of gene products, many of which appear to modulate the immune response in the host. Some deflect the host response to infection and contribute to lifelong viral persistence while others exploit immune cells that respond to infection. Here, the viral functions that modulate and mimic host major histocompatibility complex (MHC) function will be reviewed. Viral gene products related to both classical and non-classical components of the MHC system assure the virus will persist in immunocompetent individuals. Examples of host countermeasures that neutralize viral immunomodulatory functions have emerged in the characterization of viral functions that contribute to this stand-off in CMVs that infect humans, other primates and rodents. CMV-induced disease occurs when the immune system is not yet developed, such as in the developing fetus, or when it is compromised, such as in allograft transplant recipients, suggesting that the balance between virus escape and host control is central to pathogenesis. Although evidence supports the dominant role of immune escape in CMV pathogenesis and persistence, MHC-related immunomodulatory functions have been ascribed only subtle impact on pathogenesis and the immune response during natural infection. Viral gene products that interface with the MHC system may impact natural killer cell function, antigen presentation, and T lymphocyte immune surveillance. Many also interact with other cells, particularly those in the myeloid lineage, with consequences that have not been explored. Overall, the virus-encoded modulatory functions that have been acquired by CMV likely ensure survival and adaptation to the wide range of mammalian host species in which they are found. [source] Evaluating the subtle impact of a ban on corporal punishment of children in GermanyCHILD ABUSE REVIEW, Issue 5 2004Kai-D. Abstract In 2000, the German Government passed a law prohibiting physical punishment in the family. A pre,post research design allows for an examination of its effects. The results of nationwide representative surveys on the experiences, perceptions, legal knowledge and attitudes of adolescents and parents are discussed. The recent surveys reveal a signi,cant decrease in the prevalence of corporal punishments and a high acceptance of the legal prohibition. In particular, awareness of the legal limits of parental physical sanctions has increased signi,cantly. For these reasons, the prohibition of corporal punishment can be said to have had an impact on the reduction of family violence against children in Germany. Copyright © 2004 John Wiley & Sons, Ltd. [source] Flower visitors and pollination in the Oriental (Indomalayan) RegionBIOLOGICAL REVIEWS, Issue 3 2004Richard T. Corlett ABSTRACT Current knowledge of flower visitors and pollination in the Oriental Region is summarised. Much less is known about pollination than seed dispersal and the coverage of habitats and taxa in the region is very uneven. The available evidence suggests that pollination in lowland forests is dominated by highly social bees (mainly Trigona and Apis species), with beetles probably the next most important group, followed by other bees and flies. In comparison with the better-studied Neotropics, large solitary bees, moths, Lepidoptera and vertebrates are relatively less important. These differences are greatest in the canopy of the lowland dipterocarp forests of Southeast Asia, where they probably reflect the unique temporal pattern of floral resource availability resulting from,general flowering'at supra-annual intervals. Apis bees (but not Trigona species) are also important in most montane, subtropical and non-forest habitats. Apart from the figs (Ficus spp.), there are few well-documented examples of plant species visited by a single potential pollinator and most plant-pollinator relationships in the region appear to be relatively generalised. The small sizes of most pollinators and the absence of direct human exploitation probably make pollination mutualisms less vulnerable to failure as a result of human impacts than dispersal mutualisms, but more subtle impacts, as a result of altered gene flows, are likely to be widespread. On current evidence, pollination systems in the Oriental Region do not require any specific conservation action, but this review reinforces arguments for making the preservation (or restoration) of habitat connectivity the major focus of Oriental conservation. [source] | ||||||||||