Age-specific salivary immunoglobulin A response to Streptococcus mutans GbpB

In a follow-up study of children infected with Streptococcus mutans at an early age (children previously shown to respond poorly to S. mutans GbpB), there was a delay in their immune response, rather than a complete inability to respond to this antigen. Epitopes in the N-terminal third of GbpB were identified as targets for naturally induced immunoglobulin A antibody in children at an early age.14680480

Class II Transactivator (CIITA) Enhances Cytoplasmic Processing of HIV-1 Pr55Gag

The Pr55(gag) (Gag) polyprotein of HIV serves as a scaffold for virion assembly and is thus essential for progeny virion budding and maturation. Gag localizes to the plasma membrane (PM) and membranes of late endosomes, allowing for release of infectious virus directly from the cell membrane and/or upon exocytosis. The host factors involved in Gag trafficking to these sites are largely unknown. Upon activation, CD4+ T cells, the primary target of HIV infection, express the class II transcriptional activator (CIITA) and therefore the MHC class II isotype, HLA-DR. Similar to Gag, HLA-DR localizes to the PM and at the membranes of endosomes and specialized vesicular MHC class II compartments (MIICs). In HIV producer cells, transient HLA-DR expression induces intracellular Gag accumulation and impairs virus release.Here we demonstrate that both stable and transient expression of CIITA in HIV producer cells does not induce HLA-DR-associated intracellular retention of Gag, but does increase the infectivity of virions. However, neither of these phenomena is due to recapitulation of the class II antigen presentation pathway or CIITA-mediated transcriptional activation of virus genes. Interestingly, we demonstrate that CIITA, apart from its transcriptional effects, acts cytoplasmically to enhance Pr160(gag-pol) (Gag-Pol) levels and thereby the viral protease and Gag processing, accounting for the increased infectivity of virions from CIITA-expressing cells.This study demonstrates that CIITA enhances HIV Gag processing, and provides the first evidence of a novel, post-transcriptional, cytoplasmic function for a well-known transactivator

Association between caries prevalence and clinical, microbiological and dietary variables in 1.0 to 0.5-year-old Brazilian children

The association between caries prevalence and clinical (presence of visible plaque in the labial surfaces of maxillary incisors), microbiological (salivary levels of mutans streptococci) and dietary variables was evaluated in 142 1.0- to 2.5-year-old children attending public day-care nurseries in the city of Piracicaba - Sao Paulo. A significant difference in caries prevalence was observed between those children with and without visible plaque (chi(2) = 12.08, p < 0.001). The mean ds (decayed surfaces) was significantly higher in children with visible plaque on the maxillary incisors than in children without it (p < 0.001). Mutans streptococci were detected in 114 (80.3%) of the children. A significantly higher caries prevalence was observed in children with high levels of mutans streptococci compared to children with low levels (chi(2) = 28.67, p < 0.001). The mean ds was significantly higher in children with levels of mutans streptococci greater than 50 CFU when compared to children with 0 CFU or 1-50 CFU of mutans streptococci (p < 0.05). Children who were either never breast-fed or only until 3 months exhibited a significantly higher caries prevalence than those breast-fed for a longer time (chi(2) = 4.11, p < 0.05). A significantly higher caries prevalence was also observed between children that used bottle containing milk with sucrose and cereal than children using bottle with milk with or without sucrose (chi(2) = 6.24, p < 0.05). Children who started to eat salty meals at or after 7 months of age showed a significant higher caries prevalence than children who started earlier (chi(2) = 10.30, p < 0.01). These data support the evidence of an association between caries prevalence in young children and mutans streptococci levels, clinical and dietary factors.32531932

Relation of oral yeast infection in Brazilian infants and use of a pacifier

The frequency of oral yeast ingestion and its relationship with sucking and feeding habits wits described in children from one to 18 months of age. Yeasts were detected in 58.3 percent of children and the most prevalent species were Candida parapsilosis and Candida albicans. The use of a pacifier was positively associated with the frequency of yeast infection and with the levels of these microorganisms in the mouth. No relationship was detected between the prevalence of yeast and breast-feeding or bottle-feeding habits. The results suggest that use of a pacifier is an important local factor in the colonization and proliferation of yeast in the oral cavity.68133