Risk markers associated with challenging behaviours in people with intellectual disabilities: a meta-analytic study.

A meta-analysis of prevalence and cohort studies conducted over the last 30 years was carried out to identify risk markers for challenging behaviour shown by individuals with intellectual disabilities (IDs). A total of 86 potential studies was identified from the review, with 22 (25.6%) containing sufficient data to enable a statistical analysis to be conducted. Results indicated that males were significantly more likely to show aggression than females, and that individuals with a severe/profound degree of ID were significantly more likely to show self-injury and stereotypy than individuals with a mild/moderate degree of ID. Individuals with a diagnosis of autism were significantly more likely to show self-injury, aggression and disruption to the environment whilst individuals with deficits in receptive and expressive communication were significantly more likely to show self-injury. In most cases, tests for heterogeneity were statistically significant, as expected. The meta-analysis highlighted the paucity of methodologically robust studies of risk markers for challenging behaviours and the lack of data on incidence, prevalence and chronicity of challenging behaviour in this population.

A logical sequence search for S100B target proteins.

The EF-hand calcium-binding protein S100B has been shown to interact in vitro in a calcium-sensitive manner with many substrates. These potential S100B target proteins have been screened for the preservation of a previously identified consensus sequence across species. The results were compared to known structural and in vitro properties of the proteins to rationalize choices for potential binding partners. Our approach uncovered four oligomeric proteins tubulin (alpha and beta), glial fibrillary acidic protein (GFAP), desmin, and vimentin that have conserved regions matching the consensus sequence. In the type III intermediate filament proteins (GFAP, vimentin, and desmin), this region corresponds to a portion of a coiled-coil (helix 2A), the structural element responsible for their assembly. In tubulin, the sequence matches correspond to regions of alpha and beta tubulin found at the alpha beta tubulin interface. In both cases, these consensus sequence matches provide a logical explanation for in vitro observations that S100B is able to inhibit oligomerization of these proteins.

Specificity and Zn2+ enhancement of the S100B binding epitope TRTK-12.

The calcium-binding protein S100B (an S100 dimer composed of two S100beta monomers) is proposed to act as a calcium-sensory protein through interactions with a variety of proteins. While the nature of the exact targets for S100B has yet to be defined, random bacteriophage peptide mapping experiments have elucidated a calcium-sensitive "epitope" (TRTK-12) for S100B recognition. In this work, interactions of TRTK-12 with S100B have been shown to be calcium-sensitive. In addition, the interactions are enhanced by zinc binding to S100B, resulting in an approximate 5-fold decrease in the TRTK-12/S100B dissociation constant. Moreover, Zn2+ binding alone has little effect. TRTK-12 showed little evidence for binding to another S100 protein, S100A11 or to a peptide derived from the N terminus of S100B, indicating both a level of specificity for TRTK-12 recognition by S100B and that the N-terminal region of S100B is probably not involved in protein-protein interactions. NMR spectroscopy revealed residues most responsive to TRTK-12 binding that could be mapped to the surface of the three-dimensional structure of calcium-saturated S100B, revealing a common region indicative of a binding site.

Estimation of the caries-related risk associated with infant formulas.

PURPOSE: Baby bottle tooth decay (BBTD) affects 6% of children under three years of age and is associated with inappropriate bottle use. The objective of this study was to estimate the caries-related risk associated with 26 infant formulas and whole milk. METHODS: First, the plaque pH of adult volunteers was monitored before and after an oral rinse with infant formula to determine the minimum pH obtained in response to each formula. Second, Streptococcus sobrinus 6715 was cultured in each infant formula, and the increase in the number of colony forming units was measured. Third, each infant formula was incubated with powdered enamel and the solubility of enamel mineral was calculated in the absence of bacteria. Fourth, each formula was mixed with standardized concentrations of acid to determine the buffering capabilities. Finally, enamel windows were created on extracted permanent molars and exfoliated primary incisor crowns that were then colonized with mutans streptococci and incubated with infant formula. Caries was assessed visually and radiographically for 18 weeks. The length of time required for the development of enamel caries, dentinal caries and pulpal involvement was recorded. RESULTS: One-way or two-way ANOVA of these five assays demonstrated that 1. Plaque pH varied in response to oral rinsing with infant formula and most formulas did have the ability to reduce the pH significantly below the pH obtained after rinsing with water 2. Some infant formulas supported significant bacterial growth 3. Enamel mineral was dissolved by incubation with certain infant formula 4. The buffer capacity varied among the infant formulas tested 5. The length of time required for caries to reach dentin or pulp differed for the formulas, with some formulas causing dentinal caries by 3.4 weeks and pulpal involvement by 7.2 weeks.

Identification of a 37 kDa plant protein that interacts with the turnip mosaic potyvirus capsid protein using anti-idiotypic-antibodies.

Experimental data are provided for the presence of a plant protein that interacts with the capsid protein (CP) of turnip mosaic potyvirus (TuMV). The receptor-like protein was identified by exploiting the molecular mimicry potential of anti-idiotypic antibodies. A single-chain Fv molecule derived from the monoclonal antibody 7A (Mab-7A), which recognizes the CP of TuMV, was produced in Escherichia coli and the recombinant protein was used to raise rabbit antibodies. The immune serum reacted with Mab-7A but not with a monoclonal antibody of the same isotype, indicating that anti-idiotypic antibodies were produced. These anti-idiotypic antibodies recognized a 37 kDa protein from Lactuca sativa. Complex formation between the anti-idiotypic antibodies and the plant protein was inhibited by the CP of TuMV which indicates that the plant protein interacts with the viral protein. The 37 kDa protein was localized in chloroplasts and was detected in other plant species.