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Record 1Procedural learning deficit in children with Williams syndrome. Vicari S; Bellucci S; Carlesimo GA IRCCS, Ospedale Pediatrico Bambino Gesu, Sevizio di Neuro e Riabilitazione, Lungomare Guglielmo Marconi 36, I-00058, Santa Marinella, Rome, Italy Neuropsychologia (England) 2001, 39 (7) p665-77, ISSN 0028-3932 Languages: ENGLISH Document type: Journal Article
The present study was aimed at evaluating implicit memory processes in subjects with Williams syndrome (WS) and comparing them to mental-age (MA) matched normal children. For this purpose, tests of verbal and visuo-perceptual explicit memory, verbal and visual repetition priming as well as procedural learning tasks were administered to 12 WS and 12 MA matched subjects. WS subjects showed a level of repetition priming similar to that of MA normal controls. In contrast, WS children showed a reduced learning rate in the two procedural tasks. Although deficient explicit memory and executive dysfunction cannot be excluded from the performance of WS subjects, these results suggest a specific deficit of procedural learning in this particular group of mentally retarded children. This finding is relevant for our knowledge about the qualitative aspects of the anomalous cognitive development in mentally retarded people and the neurobiological substrate underlying this development.
Record 2Cleft palate in a patient with Williams' syndrome. Blanco-Davila F; Olveda-Rodriguez JA Division of Plastic and Reconstructive Surgery, Craniofacial Surgery Clinic, University Hospital Dr. Jose E. Gonzalez, Autonomous University of Nuevo Leon, Monterrey, NL Mexico. [email protected] Journal of craniofacial surgery (United States) Mar 2001, 12 (2) p145-7, ISSN 1049-2275 Languages: ENGLISH Document type: Journal Article
Cleft lip or palate has not been reported in the medical literature as a part of Williams' syndrome. We present a patient who had cleft palate among other congenital manifestations. This patient's immediate postnatal period clinically seemed to have a Pierre Robin sequence. With the development of the craniofacial complex, microgenia and micrognathia with glossoptosis gradually became apparent. On further assessment, the patient showed other clinical findings that suggested a syndromic association. This required a complete evaluation to discard other conditions that present with low psychomotor development and distinctive facies, such as Kabuki syndrome or fetal alcohol syndrome. The diagnosis for Williams' syndrome was established based on the clinical features and supported by the fluorescent in situ hybridization test. Williams' syndrome has been described as a rare, congenital disorder characterized by physical and developmental problems. Common features include characteristic "elfin-like" facies, supravalvular aortic stenosis, hypercalcemia, low birth weight, slow weight gain, feeding problems, impulsive and outgoing personality, limited spatial skills and motor control, and intellectual disability. Although individuals with Williams' syndrome may show competence in areas such as language, music, and interpersonal relations, their IQs are usually low and they are considered moderately to mildly retarded.
Record 3del (9p) syndrome: Proposed behavior phenotype. Chilosi A; Battaglia A; Brizzolara D; Cipriani P; Pfanner L; Carey JC Stella Maris Scientific Research Institute, Division of Child Neurology and Psychiatry, Department of Procreative Medicine and Pediatrics, University of Pisa, Calambrone (Pisa), Italy. American journal of medical genetics (United States) Apr 22 2001, 100 (2) p138-44, ISSN 0148-7299 Languages: ENGLISH Document type: Journal Article
Over recent years interest in the study of behavior phenotypes has gained increasing momentum. We present three white female patients, age respectively 9 years 9 months, 14 years 6 months and 18 years at the time of the last observation, seen because of developmental delay/mental retardation, seizures and learning disabilities. Cytogenetic analysis showed a de novo deletion of the short arm of chromosome 9 in all three, with the breakpoint being located at band 9p22. Although several studies have described the somatic phenotype, analytical evaluation of verbal and non-verbal cognitive functions are lacking. Our patients received a detailed neuropsychological and linguistic evaluation that showed a particular behavior profile, in the context of mental retardation of variable degree. On selective tests there was a marked deficit in visuo-praxic and visuo-spatial skills associated with memory disturbance. Visuo-motor integration abilities [VMI; Beery, 1997] and visuo-perceptual and visuo-spatial abilities [Benton line orientation test, 1992] seemed particularly impaired, both in relation to verbal mental age (vocabulary and grammatical production/comprehension) and to some non-verbal competencies [Benton face recognition test, 1992]. The profile shows advanced performances in face recognition. In addition, there is also a dissociation between verbal and visuo-spatial short term memory. This behavior phenotype is similar to that of Williams syndrome (WS) individuals. Our patients also showed some unusual within-domain dissociations regarding linguistic abilities. To better demonstrate similarities and differences between the behavior phenotypes of the del (9p22) syndrome and WS, we studied three IQ-gender-matched WS subjects. The comparison between the cognitive phenotypes of the two syndromes shows similarities in neuropsychological pattern. We hypothesize that there is a gene within the 9p22 region responsible for the neuropsychological profile described here. Copyright 2001 Wiley-Liss, Inc.
Record 4Corpus callosum morphology of Williams syndrome: relation to genetics and behavior. Schmitt JE; Eliez S; Warsofsky IS; Bellugi U; Reiss AL Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, CA 94305-5719, USA. Developmental medicine and child neurology (England) Mar 2001, 43 (3) p155-9, ISSN 0012-1622 Languages: ENGLISH Document type: Journal Article
As the largest interhemispheric commissure in the brain, the corpus callosum is of particular interest in disorders that may preferentially affect white matter development such as Williams syndrome (WS). Individuals with WS possess a remarkable array of neurobehavioral peaks and valleys, including deficits in visuospatial ability, mathematics, and attention, but with relative preservation of language and affect. Our study measured the corpus callosum and its primary subdivisions using high-resolution MRI in 20 individuals with WS (13 females and seven males; mean age 28.5, SD 8.3 years; range 19 to 44 years) and 20 age- and sex-matched control participants (mean age 28.5, SD 8.2 years; range 19 to 48 years). Total midsagittal corpus callosum area was reduced (F=4.5, p=0.04, df=36) in the WS population. The area of the splenium (F=12.4, p=0.001, df=36) and isthmus (F=9.4, p=0.004, df=36) were disproportionately reduced in WS beyond the absolute reduction of the entire corpus callosum. These reductions are in concordance with other neuroanatomical findings of decreased parietooccipital volumes as well as the observed visuospatial problems associated with WS.
Record 5Drawing abilities in Williams syndrome: a case study. Stiles J; Sabbadini L; Capirci O; Volterra V Department of Cognitive Science 0515, University of California, San Diego, La Jolla, CA 92093-0515, USA. [email protected] Developmental neuropsychology (United States) 2000, 18 (2) p213-35, ISSN 8756-5641 Languages: ENGLISH Document type: Journal Article
Children with Williams syndrome (WS) have been reported to exhibit an unusual cognitive profile characterized by marked preservation of linguistic abilities and poor visuospatial abilities against a backdrop of generalized mental retardation. Much of the data documenting this profile come from studies of older children and adults with WS. Very few studies have reported findings from the preschool and early school-age period. As a result, little is known about the early development of cognitive processes in children with WS. Capirci, Sabbadini, and Volterra (1996) reported data from a longitudinal case study of early language development in a young child with WS. This article presents the longitudinal profile of visuospatial abilities in this same child. Data on copying and free drawing collected over a period extending from late preschool to early school age are reported. It is clear from these data that this child does indeed exhibit deficits in visuospatial abilities. Her performance clearly improved with age, but deficits persist.
Record 6Lifetime predictions for resin-based composites using cyclic and dynamic fatigue. McCool JI; Boberick KG; Baran GR Industrial and Management Engineering, Penn State Great Valley, 30 E. Swedesford Rd., Malvern, Pennsylvania 19355. Journal of biomedical materials research (United States) 2001, 58 (3) p247-53, ISSN 0021-9304 Languages: ENGLISH Document type: Journal Article
Because dental restorative materials undergo fatigue in use, testing is often performed in the laboratory to evaluate material responses to cyclic loading. The purpose of this study was to compare the lifetime predictions resulting from two methods of fatigue testing: dynamic and cyclic fatigue. Model composites were made in which one variable was the presence of a silanizing agent, and specimens tested in 4-point flexure. Cyclic fatigue was carried out at a frequency of 5 Hz, while dynamic fatigue testing spanned seven decades of stress rate application. Data were reduced and the crack propagation parameters for each material were calculated from both sets of fatigue data. These parameters were then used to calculate an equivalent static tensile stress for a 5-year survival time. The 5-year survival stresses predicted by dynamic fatigue data were approximately twice those predicted by cyclic fatigue data. In the absence of filler particle silanization, the survival stress was reduced by half. Aging in a water-ethanol solution reduced the survival stresses by a factor of four to five. Cyclic fatigue is a more conservative means of predicting lifetimes of resin-based composites. Copyright 2001 John Wiley & Sons, Inc.
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