Ly-6A is a murine antigen which is implicated in lymphocyte activation and may be involved in activation of hematopoietic stem cells. Antibody cross-linking studies and antisense experiments have suggested that Ly-6A is a lymphocyte coactivation molecule. To better understand the function of Ly-6A, we used gene targeting to produce Ly-6A null mice which are healthy and have normal numbers and percentages of hematopoietic lineages. However, T lymphocytes from Ly-6A–deficient animals proliferate at a significantly higher rate in response to antigens and mitogens than wild-type littermates. In addition, Ly-6A mutant splenocytes generate more cytotoxic T lymphocytes compared to wild-type splenocytes when cocultured with alloantigen. This enhanced proliferation is not due to alterations in kinetics of response, sensitivity to stimulant concentration, or cytokine production by the T cell population, and is manifest in both in vivo and in vitro T cell responses. Moreover, T cells from Ly-6A–deficient animals exhibit a prolonged proliferative response to antigen stimulation, thereby suggesting that Ly-6A acts to downmodulate lymphocyte responses.
The aim of this study was to investigate the relationship between crying of an infant and inflicted head injury by shaking and/or impact. During the period between January 1, 1997 and December 31, 2003, 26 cases of shaken baby syndrome (SBS) were identified in Estonia. The incidence of SBS was 28.7 per 100,000 children under 1 year of age during the whole study period. In this group there were four children from twin pairs: two twin boys and a girl from a twin pair and a boy from another twin pair. This represents 15.4% of the 26 cases. Twins in Estonia represent 2.12% of infant births. The mean age on admission was 3.9 months. According to outpatient records almost all parents (88.5%) in the study group (23/26) had contacted their family physicians and other specialists because of excessive crying or irritability of the baby prior to the admission to the hospital with SBS or death. We found that the time curve of crying was similar to the curve of highest incidence of cases of SBS except the crying curve began earlier. CONCLUSION. Our data confirm that the families with twins are at additional risk for SBS and parent's complaints of excessive crying of their infants should be taken as signal that parents need to be carefully counselled.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.