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D Thal

Publications and source records attributed to D Thal.

11 recordsLinked to original sources
PubMed2005

PDGFRalpha- and c-kit-mutated gastrointestinal stromal tumours (GISTs) are characterized by distinctive histological and immunohistochemical features.

AIMS: To study the immunohistochemical and histological features of 158 gastrointestinal stromal tumours (GISTs), consisting of 137 tumours with mutations in c-kit and platelet-derived growth factor receptor-alpha (PDGFRalpha) genes and 21 wt-GISTs. Additionally, we evaluated the localization of PDGFRalpha in the normal intestine. PDGFRalpha gene mutations were recently described in a subset of GISTs and it has been hypothesized that PDGFRalpha-mutated tumours represent a distinctive entity among GISTs. RESULTS: PDGFRalpha was expressed in ganglion bodies of the myenteric plexus and in Schwann cells but not in interstitial cells of Cajal. In contrast to other GISTs, tumours with PDGFRalpha mutations had an epithelioid phenotype and multinuclear giant cells. Kit was down-regulated in PDGFRalpha-mutated GISTs and PDGFRalpha expression was decreased in c-kit mutated tumours. Dot-like staining of Kit and PDGFRalpha was associated very frequently with mutation within the respective gene. CONCLUSIONS: Features of PDGFRalpha-mutated GISTs are multinuclear giant cells and dot-like staining for PDGFRalpha. In contrast, c-kit-mutated GISTs display a spindle cell phenotype and Kit-dots on immunohistochemistry. Our findings not only help to distinguish distinctive entities of GISTs using histological and immunhistochemical features, but also indicate that Kit and PDGFRalpha are differentially regulated in a subset of GISTs.

Aged↗
PubMed2003

Genetic association of acyl-coenzyme A: cholesterol acyltransferase with cerebrospinal fluid cholesterol levels, brain amyloid load, and risk for Alzheimer's disease.

A common polymorphism of the gene encoding acyl-coenzyme A: cholesterol acyltransferase 1 (SOAT1), which is involved in the regulation of beta-amyloid peptide generation, is associated with low brain amyloid load (P=0.03) and with low cerebrospinal fluid levels of cholesterol (P=0.005). This polymorphism of SOAT1 is also associated with reduced risk for Alzheimer's disease in ethnically distinct populations (P=0.0001, odds ratio: 0.6, 95% confidence interval 0.4-0.8).

Aged↗
PubMed2000

Validity of a parent-report measure of vocabulary and grammar for Spanish-speaking toddlers.

The validity of the Fundación MacArthur Inventario del Desarrollo de Habilidades Comunicativas: Palabras y Enunciados (IDHC:PE) was examined with twenty 20- and nineteen 28-month-old, typically developing, monolingual, Spanish-speaking children living in Mexico. One measure of vocabulary (number of words) and two measures of grammar (mean of the three longest utterances and grammatical complexity score) from the IDHC:PE were compared to behavioral measures of vocabulary (number of different words from a language sample and number of objects named in a confrontation naming task) and one behavioral measure of grammar (mean length of utterance from a language sample). Only vocabulary measures were assessed in the 20-month-olds because of floor effects on the grammar measures. Results indicated validity for assessing expressive vocabulary in 20-month-olds and expressive vocabulary and grammar in 28-month-olds.

Child Language↗
PubMed1994

Developmental and stylistic variation in the composition of early vocabulary.

Results are reported for stylistic and developmental aspects of vocabulary composition for 1,803 children and families who participated in the tri-city norming of a new parental report instrument, the MacArthur Communicative Development Inventories. We replicate previous studies with small samples showing extensive variation in use of common nouns between age 0; 8 and 1;4 (i.e. 'referential style'), and in the proportion of vocabulary made up of closed-class words between 1;4 and 2;6 (i.e. 'analytic' vs. 'holistic' style). However, both style dimensions are confounded with developmental changes in the composition of the lexicon, including three 'waves' of reorganization: (I) an initial increase in percentage of common nouns from 0 to 100 words, followed by a proportional decrease; (2) a slow linear increase in verbs and other predicates, with the greatest gains taking place between 100 and 400 words; (3) no proportional development at all in the use of closed-class vocabulary between 0 and 400 words, followed by a sharp increase from 400 to 680 words. When developmental changes in noun use are controlled, referential-style measures do not show the association with developmental precocity reported in previous studies, although these scores are related to maternal education. By contrast, when developmental changes in grammatical function word use are controlled, high closed-class scores are associated with a slower rate of development. We suggest that younger children may have less perceptual acuity and/or shorter memory spans than older children with the same vocabulary size. As a result, the younger children may ignore unstressed function words until a later point in development while the older children tend to reproduce perceptual details that they do not yet understand. Longitudinal data show that early use of function words (under 400 words) is not related to grammatical levels after the 400-word point, confirming our 'stylistic' interpretation of early closed-class usage. We close with recommendations for the unconfounding of stylistic and developmental variance in research on individual differences in language development, and provide look-up tables that will permit other investigators to pull these aspects apart.

Child Language↗
PubMed1994

Relationships between language and gesture in normally developing and late-talking toddlers.

Seventeen toddlers with specific expressive language delay (14 boys and 3 girls between 18 and 33 months of age) were compared to two control groups, one matched for language production and the other matched for age and language comprehension, on measures of spontaneous and imitated gesture production. Late talkers performed like age/comprehension-matched controls on all experimental measures of gesture production and on production of later appearing, more symbolic gestures as reported by parents. Late talkers performed like language-matched controls on earlier appearing communicative gestures and gestural routines as reported by parents. All three groups produced more gestures in canonical imitation conditions than spontaneously. Results are discussed in the contexts of the Local Homology Model and characteristics of toddlers with specific expressive language delay.

Child Language↗
PubMed1993

Early lexical development in Spanish-speaking infants and toddlers.

This paper describes the early lexical development of a group of 328 normal Spanish-speaking children aged 0;8 to 2;7. First the development and structure of a new parent report instrument, Inventario del Desarollo de Habilidades Communicativas is described. Then five studies carried out with the instrument are presented. In the first study vocabulary development of Spanish-speaking infants and toddlers is compared to that of English-speaking infants and toddlers. The English data were gathered using a comparable parental report, the MacArthur Communicative Development Inventories. In the second study the general characteristics of Spanish language acquisition, and the effects of various demographic factors on that process, are examined. Study 3 examines the differential effects of three methods of collecting the data (mail-in, personal interview, and clinic waiting room administration). Studies 4 and 5 document the reliability and validity of the instrument. Results show that the trajectories of development are very similar for Spanish- and English-speaking children in this age range, that children from varying social groups develop similarly, and that mail-in and personal interview administration techniques produce comparable results. Inventories administered in a medical clinic waiting room, on the other hand, produced lower estimates of toddler vocabulary than the other two models.

Child Development↗
PubMed1991

Language and gesture in late talkers: a 1-year follow-up.

A 1-year follow-up of relationships between language and symbolic gesture in 10 children with delayed onset of early lexical skills (Thal & Bates, 1988a) is reported. Original data are reevaluated in light of new knowledge about which late talkers continued to be significantly delayed 1 year later (truly delayed) and which ones had "caught up" (late bloomers). Results showed that all 4 children who were truly delayed at follow-up had been delayed in language comprehension at the first visit, but the 6 late bloomers had been at the same level as their age-matched controls. In addition, truly delayed late talkers had been significantly poorer on all of the gesture tasks than late talkers who caught up.

Child, Preschool↗
PubMed1989

Language and cognition in two children with Williams syndrome.

In this study, aspects of language, single-gesture retrieval, combinatorial play, and visual-spatial cognition are reported in two children with Williams syndrome who were in the single-word stage of language acquisition. Williams syndrome children are of particular interest because, when older (10-15 years), they display an unusual profile of abilities that may include superior linguistic performance compared with other aspects of cognition. The two children in the present study are compared to a group of normal children in the single-word stage of language acquisition with a mean age of 14.8 months, a group of single-word stage children who are 6-18 months delayed, and a group of older normal children with a mean age of 23.5 months. Results are compatible with the unusual cognitive profile displayed by older Williams syndrome children. We discuss the possibility that this profile involves mechanisms that extend beyond the boundaries of language proper.

Child, Preschool↗
PubMed1988

Language and gesture in late talkers.

The relationship between language and symbolic gesture was studied in a group of young children who were in the lowest 10% for language production for their age based on information obtained from language inventories filled out by their parents. On a single scheme imitation task, designed to be a gestural analog of lexical production, subjects performed like controls matched for language production. On a multischeme imitation task, designed to be a gestural analog of syntax, subjects performed like age-matched controls, and significantly better than language-matched controls. Potential reasons for this dissociation are discussed in the context of predictors of early language success or impairment.

Child, Preschool↗
PubMedDate not supplied

Measuring variability in early child language: don't shoot the messenger.

Feldman et al. criticize the MacArthur Communicative Development Inventories (CDIs) as having too much variability, too little stability, and insufficient ability to predict early language delay. We present data showing that these characteristics of the CDI are authentic reflections of individual differences in early language development rather than measurement deficiencies. We also respond to their critical assertions concerning sociodemographic influences on the CDI scores.

Child Development↗