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Many studies have suggested that the concept of "number" is relatively independent from linguistic skills, although an increasing number of studies suggest that language abilities may play a pivotal role in the development of arithmetic skills. The condition of bilingualism can offer a unique perspective into the role of linguistic competence in numerical development. The present study was aimed at evaluating the relationship between language skills and early numeracy through a multilevel investigation in monolingual and bilingual minority children attending preschool. The sample included 156 preschool children. Of these, 77 were bilingual minority children (mean age D 58.27 ± 5.90), and 79 were monolinguals (mean age D 58.45 ± 6.03). The study focused on three levels of analysis: group differences in language and number skills, concurrent linguistic predictors of early numeracy and, finally, profile analysis of linguistic skills in children with impaired vs. adequate numeracy skills. The results showed that, apart from the expected differences in linguistic measures, bilinguals differed from monolinguals in numerical skills with a verbal component, such as semantic knowledge of digits, but they did not differ in a pure non-verbal component such as quantity comparison. The multigroup structural equation model indicated that letter knowledge was a significant predictor of the verbal component of numeracy for both groups. Phonological awareness was a significant predictor of numeracy skills only in the monolingual group. Profile analysis showed that children with a selective weakness in the non-verbal component of numeracy had fully adequate verbal skills. Results from the present study suggest that only some specific components of language competence predict numerical processing, although linguistic proficiency may not be a prerequisite for developing adequate early numeracy skills. [ABSTRACT FROM AUTHOR]

In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages -French, Spanish, and Arabic- that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features. [ABSTRACT FROM AUTHOR]

An intranasal (i.n.) dosing model was developed in mice as a potential alternative to more difficult, time-consuming, and costly guinea pig intratracheal (GPIT) or mouse intratracheal models for assessment of the respiratory immunogenicity of detergent enzymes. Using a benchmark enzyme, Alcalase (protease subtilisin Carlsberg), studies were conducted to standardize the model in terms of mouse strain, dosing and serum harvest regimen, and the primary immunoglobulin endpoint to use. The primary assay endpoint selected was the enzyme-specific IgG1 titer determined by an Alcalase-specific ELISA. This is not the primary allergenic antibody in mice (IgE is); however, IgG1 is coregulated with IgE via the IL-4/TH2 pathway and may have a role in mediating allergic-type responses. BDF1 mice (C57B1/6 × DBA/2) were selected as representative of high responder strains, with high response associated with the H-2b (C57B1/6) parent. The dosing regimen used for most studies incorporated three i.n. exposures (Days 1, 3, and 10) and bleeding of the animals on Day 15. The animals were anesthetized and then immunized by allowing them to inhale 5-μl aliquots of dosing solution into each nostril at each immunization. Positioning of the animals with their heads down (vs up) may have allowed more of the dosing solution to remain in the nasal region for a slightly longer period of time, but did not change the eventual GI tract migration and excretion of each dose. The presence of a detergent matrix in the enzyme dosing solution enhanced the IgG1 response. Immunizing with enzyme plus detergent gave highly consistent dose-response curves for Alcalase when evaluated over many studies. An enzyme-specific allergic antibody (IgE) response was weak and inconsistent under the dosing regimen used to generate the IgG1 response, but was stronger with longer-term dosing, consistent with the delay in IgE vs IgG1 responses seen in some other studies. Using IgG1 as a surrogate for allergic sensitization, we have preliminary data showing similar differential potencies between Alcalase and other test enzymes as detected in previous GPIT tests. On the basis of these data, we believe the i.n. immunization/IgG1 response model is a robust technique that may be useful in determining the relative immunogenicities of detergent enzymes and other proteins. [ABSTRACT FROM PUBLISHER]

The primary objective of this study was to examine the feasibility of using a mouse model to evaluate the immunogenicity of proteins as a potential method to determine occupational exposure guidelines. Mice were intratracheally administered a benchmark protein allergen, subtilisin Carlsberg (Alcalase) in detergent matrix once a week for 4 to 6 weeks and specific IgE and IgG1 levels were determined. In all experiments, specific IgE levels were determined by using a rat basophilic leukemia cell (RBL) release assay, while specific IgG1 was measured by an ELISA. A good correlation was observed between IgE titers determined by the RBL assay and rat passive cutaneous anaphylaxis assay. Intratracheal administration of protease with detergent matrix was found to result in significant IgE and IgG1 responses that were dose related. Detergent matrix was found to enhance the Alcalase-specific IgE and IgG1 response when administered by the intratracheal route. The IgG1 response was much more robust, easier to measure, and found to follow the IgE response. These results suggest that a mouse intratracheal model is a feasible approach to examining the immunogenic potency of enzymes using specific IgE or IgG1 as the end points. Additional development and validation of the mouse model with other types of proteins will be pursued. [ABSTRACT FROM AUTHOR]