Human and Animal Isolates of Yersinia enterocolitica Show Significant Serotype-Specific Colonization and Host-Specific Immune Defense Properties

Yersinia enterocolitica is a human pathogen that is ubiquitous in livestock, especially pigs. The bacteria are able to colonize the intestinal tract of a variety of mammalian hosts, but the severity of induced gut-associated diseases (yersiniosis) differs significantly between hosts. To gain more information about the individual virulence determinants that contribute to colonization and induction of immune responses in different hosts, we analyzed and compared the interactions of different human- and animal-derived isolates of serotypes O:3, O:5,27, O:8, and O:9 with murine, porcine, and human intestinal cells and macrophages. The examined strains exhibited significant serotype-specific cell binding and entry characteristics, but adhesion and uptake into different host cells were not host specific and were independent of the source of the isolate. In contrast, survival and replication within macrophages and the induced proinflammatory response differed between murine, porcine, and human macrophages, suggesting a host-specific immune response. In fact, similar levels of the proinflammatory cytokine macrophage inflammatory protein 2 (MIP-2) were secreted by murine bone marrow-derived macrophages with all tested isolates, but the equivalent interleukin-8 (IL-8) response of porcine bone marrow-derived macrophages was strongly serotype specific and considerably lower in O:3 than in O:8 strains. In addition, all tested Y. enterocolitica strains caused a considerably higher level of secretion of the anti-inflammatory cytokine IL-10 by porcine than by murine macrophages. This could contribute to limiting the severity of the infection (in particular of serotype O:3 strains) in pigs, which are the primary reservoir of Y. enterocolitica strains pathogenic to humans.     

Staphylococcal and Streptococcal Superantigen Exotoxins

SUMMARY

This review begins with a discussion of the large family of Staphylococcus aureus and beta-hemolytic streptococcal pyrogenic toxin T lymphocyte superantigens from structural and immunobiological perspectives. With this as background, the review then discusses the major known and possible human disease associations with superantigens, including associations with toxic shock syndromes, atopic dermatitis, pneumonia, infective endocarditis, and autoimmune sequelae to streptococcal illnesses. Finally, the review addresses current and possible novel strategies to prevent superantigen production and passive and active immunization strategies.     

Delinquency in incarcerated male adolescents is associated with single parenthood,exposure to more violence at home and in the community,and poorer self-image

Aim

To assess the relationships between delinquency and demographic and family variables, academic performance, war stressors, home/community, school, and media violence exposure, self-image, and psychopathology.

Methods

This cross-sectional study included 100 delinquent, incarcerated male adolescents and 100 matched schoolchildren from Croatia. It lasted from January 2008 to June 2009, and used socio-demographic questionnaire, questionnaire on children’s stressful and traumatic war experiences, exposure to violence scale, the Offer Self-Image Questionnaire, and Youth Self-Report Questionnaire.

Results

Logistic regression analysis showed that delinquency in incarcerated adolescents was more likely related to having parents who did not live together (odds ratio [OR] 2.40; confidence interval [CI] 1.18-4.90, P = 0.015), being more exposed to violence at home/community (OR 3.84; CI 1.58-9.34, P = 0.003), and having poorer self-image (OR 1.09; CI = 1.03-1.16, P < 0.002).

Conclusion

Preventive and therapeutic interventions in incarcerated delinquents should be specifically targeted toward single parenthood, family factors, trauma oriented interventions, and focused on multiple dimensions of self-concept of adolescents.Delinquency is associated with many risk factors, including demographic, genetic, and family characteristics (single parenthood) or academic performance. Many studies have focused on exposure to various forms of violence – in the family or home; community and neighborhood; in school and peer groups; and the media, but other risk factors have also found to be important, such as poorer self-image, various forms of psychopathology, and social characteristics (neighborhoods characterized by poverty) (1-15). Most of the studies dealing with delinquency aim to develop therapeutic interventions in relation to the obtained factors or mediators (9,11,16).There are relatively few studies on incarcerated adolescents. Many report on delinquents’ traumatic experiences, posttraumatic stress disorder, and importance of developmental tasks of adolescence and parental monitoring (14,17,18). Therapeutic interventions are specifically directed toward assessment and intervention of trauma and psychopathology, and family interventions are used very often.There are not many studies on delinquents in Croatia and most of them deal with a model that takes into account the interplay between protective and risk factors (19-21). Factors that are often mentioned are parental distrust and punishment, and family dysfunctionality (22-24). The prevalence of delinquency in the last few years has not been reducing (25), which suggests that the current preventive and therapeutic efforts have not been sufficient (25). Another important factor that has to be considered when studying delinquency in Croatia is the influence of Croatian War for Independence 1991-1995. The relationship between war experiences (direct or indirect) and the development of delinquency in adolescents has been relatively rarely described, with contradictory findings. Some studies found no association between the impact of war and bullying (26), whereas others found a relationship between aggressiveness in child refugees and their past war experiences (27) or experiences of their parents, war veterans (28). Besides war-related violence, we expected that delinquency was related to the exposure to other types of violence, eg, violence at home (29). Finally, we also expected an association with poorer self-image (8) and the presence of significant psychopathological syndromes (7).Our aim was therefore to examine the relationship between demographic, family factors, academic performance, exposure to violence in different contexts (home, community, school, media, war related stress), psychopathology, and delinquency.