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International Journal of Paediatric Dentistry 2013; 23: 32-38 Background Salivary levels of Bifidobacteria have been shown to be significantly correlated with caries experience in adults but not as yet in children. Hypothesis. Salivary levels of Bifidobacteria are positively associated with caries experience in children. Aim. To compare the salivary concentrations of Bifidobacteria of caries-free and caries-active children. Design. Saliva was collected using the tongue-loop method from 38 caries-active children and from 22 clinically caries-free children, and the numbers of Bifidobacteria, mutans streptococci, lactobacilli and yeasts were determined. Additionally, the age and gender of the children, a plaque index, sugar amount in diet, sugar frequency in diet, hygiene practice and fluoride toothpaste usage were recorded. Results. Bifidobacteria were isolated from 95% of the caries-active children and from only 9% of the caries-free children ( P < 0.001). Salivary levels of Bifidobacteria were significantly correlated with amount of sugar in the diet, frequency of sugar consumption and oral hygiene practice. The significant variables that discriminated between the caries-free and caries-active subjects were salivary levels of Bifidobacteria, salivary levels of mutans streptococci and oral hygiene practice (χ2 = 72.57, P < 0.001) and overall 90.0% of cases were correctly classified. Conclusions. Salivary levels of Bifidobacteria are significantly associated with caries experience in children. The salivary levels of this genus may be a useful marker of caries risk. [ABSTRACT FROM AUTHOR]

The World Library of Toxicology, Chemical Safety, and Environmental Health, commonly referred to as the World Library of Toxicology (WLT), is a multilingual online portal of links to key global resources, representing a host of individual countries and multilateral organizations. The Site is designed as a network of, and gateway to, toxicological information and activities from around the world. It is built on a Wiki platform by a roster of Country Correspondents, with the aim of efficiently exchanging information and stimulating collaboration among colleagues, and building capacity, with the ultimate objective of serving as a tool to help improve global public health. The WLT was publicly launched on September 7, 2009, at the Seventh Congress of Toxicology in Developing Countries (CTDC-VII) in Sun City, South Africa. [ABSTRACT FROM PUBLISHER]

Given established scientific knowledge, protecting children from neurotoxic exposures from the earliest stages of fetal development is clearly an essential public health measure. By reducing environmental factors that may lead to learning and developmental disorders, we will create a healthier environment in which all children can reach and maintain their full potential. (Gilbert, 2008) [ABSTRACT FROM AUTHOR]

Streptococcus mutans, consisting of serotypes c, e, f and k, is an oral aciduric organism associated with the initiation and progression of dental caries. A total of 135 independent Streptococcus mutans strains from caries-free and caries-active subjects isolated from various geographical locations were examined in two versions of an MLST scheme consisting of either 6 housekeeping genes [accC (acetyl-CoA carboxylase biotin carboxylase subunit), gki (glucokinase), lepA (GTP-binding protein), recP (transketolase), sodA (superoxide dismutase), and tyrS (tyrosyl-tRNA synthetase)] or the housekeeping genes supplemented with 2 extracellular putative virulence genes [gtfB (glucosyltransferase B) and spaP (surface protein antigen I/ II)] to increase sequence type diversity. The number of alleles found varied between 20 (lepA) and 37 (spaP). Overall, 121 sequence types (STs) were defined using the housekeeping genes alone and 122 with all genes. However p, nucleotide diversity per site, was low for all loci being in the range 0.019-0.007. The virulence genes exhibited the greatest nucleotide diversity and the recombination/mutation ratio was 0.67 [95% confidence interval 0.3-1.15] compared to 8.3 [95% confidence interval 5.0-14.5] for the 6 concatenated housekeeping genes alone. The ML trees generated for individual MLST loci were significantly incongruent and not significantly different from random trees. Analysis using ClonalFrame indicated that the majority of isolates were singletons and no evidence for a clonal structure or evidence to support serotype c strains as the ancestral S. mutans strain was apparent. There was also no evidence of a geographical distribution of individual isolates or that particular isolate clusters were associated with caries. The overall low sequence diversity suggests that S. mutans is a newly emerged species which has not accumulated large numbers of mutations but those that have occurred have been shuffled as a consequence of intra-species recombination generating genotypes which can be readily distinguished by sequence analysis. [ABSTRACT FROM AUTHOR]