Tissue formation and host remodeling of an elastomeric biodegradable scaffold in an ovine pulmonary leaflet replacement model.

In pursuit of a suitable scaffold material for cardiac valve tissue engineering applications, an acellular, electrospun, biodegradable polyester carbonate urethane urea (PECUU) scaffold was evaluated as a pulmonary valve leaflet replacement in vivo. In sheep (n = 8), a single pulmonary valve leaflet was replaced with a PECUU leaflet and followed for 1, 6, and 12 weeks. Implanted leaflet function was assessed in vivo by echocardiography. Explanted samples were studied for gross pathology, microscopic changes in the extracellular matrix, host cellular re-population, and immune responses, and for biomechanical properties. PECUU leaflets showed normal leaflet motion at implant, but decreased leaflet motion and dimensions at 6 weeks. The leaflets accumulated α-SMA and CD45 positive cells, with surfaces covered with endothelial cells (CD31+). New collagen formation occurred (Picrosirius Red). Accumulated tissue thickness correlated with the decrease in leaflet motion. The PECUU scaffolds had histologic evidence of scaffold degradation and an accumulation of pro-inflammatory/M1 and anti-inflammatory/M2 macrophages over time in vivo. The extent of inflammatory cell accumulation correlated with tissue formation and polymer degradation but was also associated with leaflet thickening and decreased leaflet motion. Future studies should explore pre-implant seeding of polymer scaffolds, more advanced polymer fabrication methods able to more closely approximate native tissue structure and function, and other techniques to control and balance the degradation of biomaterials and new tissue formation by modulation of the host immune response.

Complete edentulism prior to the age of 65 years is associated with all-cause mortality.

PURPOSE: We examine the relationship between complete edentulism prior to the age of 65 years and all-cause mortality after adjustment for socioeconomic characteristics. METHODS: Using data from 41,000 adult participants in the 1986 National Health interview Survey with mortality follow-up data on each cohort member through December 31, 2002 (16 years follow-up), we estimated the relative odds of all-cause mortality among adults (age > or =18 years) with complete edentulism prior to the age of 65 years compared with that among those without the condition. Multivariable-adjusted logistic regression analyses were repeated for complete edentulism at any age. RESULTS: The age-standardized prevalence of complete edentulism was 12.3 percent [95 percent confidence interval (CI), 12.0-12.6]. Among persons aged <65 years, the risk of death from all causes was 19 percent for persons with complete edentulism compared to 10 percent for persons without. Compared with those without complete tooth loss, the risk of death from all causes was 1.5 (95 percent CI, 1.3-1.7) (P < 0.001) times greater for persons with complete edentulism prior to the age of 65 years after multivariable adjustment. Similar results were observed for complete edentulism among persons aged > or =65 years. CONCLUSIONS: Complete edentulism prior to the age of 65 years was associated with all-cause mortality after multivariable adjustment for several socioeconomic characteristics. These results provide further evidence supporting the notion that poor oral health as evidenced by complete edentulism is an important public health issue across the lifespan.

Sublingually administered Bacillus subtilis cells expressing tetanus toxin C fragment induce protective systemic and mucosal antibodies against tetanus toxin in mice.

Sublingual (SL) immunization against infectious agents or bacterial toxins is not a common route for antigen delivery. However, in our continued search for a needle-free platform for vaccine administration, we evaluated the efficacy of SL immunization with Bacillus subtilis engineered to express tetanus toxin fragment C (TTFC). We compared the results obtained with those for intranasal (IN) immunization with the same vaccine, which we recently reported to induce complete protection in mice against a 2×LD100 challenge of tetanus toxin (Lee et al., Vaccine 28:6658-65). Groups of animals received 3-4 immunizations of 10(9)B. subtilis vegetative cells expressing TTFC given IN or SL. Other SL immunized groups received either purified recombinant TTFC (rTTFC) or B. subtilis placebo. A non-toxic mutant of Escherichia coli heat labile enterotoxin (mLT) was included as adjuvant in some of the studies. Mice inoculated by either IN or SL administration developed protective IgG antibodies against tetanus toxin challenge. Similar of higher IgA levels in saliva, vaginal wash and feces were detected in animals immunized SL with B. subtilis cells expressing TTFC compared with IN-immunized mice or mice immunized SL with rTTFC. SL immunization promoted a mixed Th1/Th2 response, based on cytokine analysis (IL-2, IL-4, IL-10 and INFγ). Antigen-stimulated tissues (lung, intestine, spleen and lymph nodes) revealed a dramatic increase in the density of MHC class II+ expressing cells compared to all other groups. The antibody response to TTFC was superior when the adjuvant mLT was excluded from IN and SL immunizations. However, SL administration of mLT induced strong systemic and mucosal antibody responses, indicating that successful use of this route of immunization is not specific to tetanus toxin. We conclude that SL immunization is a promising, effective, safe, non-invasive and convenient method for mucosal delivery of B. subtilis cells expressing tetanus vaccine and, potentially, other immunogens. SL immunization appears to induce both systemic and mucosal immune responses.

Diagnosis of rubella infection by detecting specific immunoglobulin M antibodies in saliva samples: a clinic-based study in Niterói, RJ, Brazil

Este estudo foi realizado para avaliar a validade da utilizaçäo da saliva no diagnóstico laboratorial da rubéola. Quarenta e cinco amostras pareadas de sangue e de saliva, coletadas de 1 a 29 dias após o início da doença, foram testadas para detecçäo de imunoglobulina (Ig) M específica por radioimunoensaio com captura (MACRIA). Anticorpos IgM específicos contra rubéola foram detectados em todas as amostras sanguíneas e em 38 (84,4 por cento) das amostras de saliva. A especificidade do teste na saliva foi de 96 por cento. Estes resultados indicam que a utilizaçäo da saliva pode ser uma alternativa válida para obtençäo de espécimens clínicos na investigaçäo de casos recentes de rubéola, especialmente nas atividades de vigilância epidemiológica e controle da virose