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31.
BACKGROUND: Language abilities of siblings of children with autism were examined to explore the possibility that language abilities are behavioral markers specific to the genetic liability for autism, as part of the broader phenotype. METHOD: Language abilities were compared among 27 siblings of children with autism, 23 siblings of children with mental retardation of unknown etiology (MR), and 22 siblings of children with developmental language disorders (DLD). Groups were matched by siblings' age, gender, birth order, family size, ethnicity, family income and by probands' gender and mental age. RESULTS: Siblings of children with autism achieved higher scores than siblings of children with DLD on receptive, expressive, and total language scales of the Children's Evaluation of Language Fundamentals and on verbal IQ. Moreover, within the DLD group, school problems in the domains of reading and arithmetic were more prevalent than within the other two groups. Only 2 siblings of children with autism received clinical diagnoses based on DSM-IV criteria compared to 3 siblings of children with MR and 7 siblings of children with DLD. CONCLUSIONS: After excluding data of the diagnosed siblings, no differences in language abilities could be discerned among the groups, except that more siblings in the DLD group were identified as having language difficulties. In summary, although language deficits characterize autism, siblings of children with autism were not found to demonstrate deficits in language skills assessed by formal language tests, IQ, or academic skills.  相似文献   
32.
BACKGROUND: The aim of this study was to compare the efficacy of interferon alpha (IFN) or IFN and ribavirin (IFN+RIB) combination therapy in children with chronic hepatitis C (CHC). Most children were infected during treatment for pediatric malignancies. PATIENTS AND METHODS: We reviewed the charts of 20 patients (11 boys and 9 girls) aged 10.6 +/- 3.7 years with CHC who were treated between 1995 and 2001. Seven patients diagnosed with CHC before 1998 were treated with 3 million units of IFN three times weekly for 6 to 12 months. Thirteen children diagnosed after 1998 were treated with 3 million units of IFN three times weekly plus 15 mg/kg of ribavirin daily for 6 months (IFN+RIB). RESULTS: Demographic and clinical characteristics were not different between the two treatment groups. A sustained complete response defined as serum alanine aminotransferase normalization and hepatitis C virus RNA clearance at 6 and 12 months after termination of treatment occurred in three of seven children (43%) treated with IFN monotherapy compared with 7 of 12 children (54%) in the group treated with IFN+RIB combination therapy (not significant). The only difference between responders and nonresponders was the duration of infection before the initiation of therapy, which was significantly shorter in responders (1 +/- 0.3 vs. 5.6 +/- 2.2; P = 0.001). CONCLUSIONS: In this small cohort of children with CHC, early initiation of antiviral treatment was associated with a sustained response rate independent of treatment type. Regular follow-up of children at risk of acquiring hepatitis C virus infection should assist in the early diagnosis. Early initiation of antiviral treatment may improve the rate of sustained response.  相似文献   
33.
Insulin does not mediate glucose stimulation of proinsulin biosynthesis   总被引:2,自引:0,他引:2  
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34.
AIMS AND BACKGROUND: Classical irradiation of carcinoma of the nasopharynx involves large fields and high doses; therefore, significant late toxicity and late side effects are to be expected. Given the fact that nasopharyngeal carcinoma (NPC) is a relatively radiosensitive disease and a significant proportion of patients are long-term survivors, late visual and auditory complications of treatment are of utmost concern for patients and radiation oncologists. The aim of this study was to evaluate the long-term visual and auditory toxicity in patients treated with radiotherapy for NPC. METHODS AND STUDY DESIGN: Forty-three long-term survivors (including 11 children), following definitive radiotherapy for NPC, underwent a thorough visual and auditory evaluation 2-22 years after their treatment. Ophthalmological examination consisted of anamnesis of dry eye syndrome and visual acuity, visual acuity testing, slit-lamp examination, Schirmer test, fundus examination, and intraocular pressure measurement, as well as fluorescein angiography in patients with pathological vascular findings in the fundus examination. Audiological evaluation included anamnesis of hearing loss, tinnitus or vertigo, examination of the ears and nasopharynx, audiogram, and tympanogram. RESULTS: Radiation retinopathy was found in 16% of patients by fundus examination, with one patient (2.3%) developing blindness. Severe dry eye syndrome was present in 26%. Fifty-six percent had some degree of hearing impairment, with 74% showing severe sensorineural hearing loss. Fifty-eight percent of patients reported tinnitus and 26% reported suffering from dizziness. Radiation retinopathy as well as all manifestations of auditory toxicity were found to bear a direct correlation with dose per fraction. CONCLUSIONS: Unless there is tumor involvement, the orbital contents should be completely excluded from the target volume. Auditory toxicity is significant when treating NPC with two-dimensional techniques.  相似文献   
35.
BACKGROUND: Schizophrenia is comprised of several debilitating symptoms. Antipsychotics offer an effective treatment for positive symptoms, while the negative signs and cognitive deficits are usually treatment-resistant. It was suggested that glutamate dysregulation may be involved in the neuropathology of schizophrenia, mainly through NMDA dysfunction. We hypothesized that addition of memantine, a weak non-selective NMDA receptor antagonist approved for dementia, to antipsychotics would improve the clinical status of un-remitted schizophrenia patients, notably the negative signs and cognitive deficits. METHODS: Seven schizophrenia patients, were included in a six-week open-label study, with weekly increasing dosage (5, 10, 15, 20 mg) of memantine added to their on-going antipsychotic treatment. RESULTS: We found a significant improvement of the PANSS score (baseline 116.28+/-21.9 vs. 97.86+/-24.48 after six weeks, t=5.98, p<0.001) with the most prominent improvement (21%) in negative signs sub-scale (baseline 40+/-6.38 vs. 31.71+/-7.76 after six weeks, t=5.87, p<0.001). Cognitive status, measured with the Neurobehavioral Cognitive Examination (NCSE) and Clock Drawing Test (CDT) showed no improvement. CONCLUSION: Memantine addition to antipsychotic treatment, in schizophrenia patients might improve their clinical status, primarily the negative signs, but not their cognitive deficits. Further research is needed to replicate these observations.  相似文献   
36.
This study ascertained serum vitamin B12 levels among patients with Gaucher disease and among healthy Israelis. Serum B12 and metabolites' levels were studied in consecutive adult patients with Gaucher disease not treated with enzyme plus Ashkenazi Jewish neighbour-controls, together with healthy blood-donor volunteers of various ethnicities. Each group showed a high incidence of low serum B12 concentrations, with a 22.3% incidence among Ashkenazi Jews and 40% among patients with Gaucher disease. These findings raise questions on the individual and community levels of serum B12. We recommend evaluation of B12 levels among geographically contingent peoples.  相似文献   
37.
Substrate autoregulation of glucose transporter-1 (GLUT-1) mRNA and protein expression provides vascular endothelial and smooth muscle cells a sensitive mechanism to adapt their rate of glucose transport in response to changing glycemic conditions. Hyperglycemia-induced downregulation of glucose transport is particularly important in protecting these cells against an excessive influx of glucose and consequently increased intracellular protein glycation and generation of free radicals; both are detrimental in the development of vascular disease in diabetes. We aimed to investigate the molecular mechanism of high glucose-induced downregulation of GLUT-1 mRNA expression in primary bovine aortic vascular endothelial (VEC) and smooth muscle (VSMC) cell cultures. Using RNA mobility shift, UV cross-linking, and in vitro degradation assays, followed by mass-spectrometric analysis, we identified calreticulin as a specific destabilizing trans-acting factor that binds to a 10-nucleotide cis-acting element (CAE(2181-2190)) in the 3'-untranslated region of GLUT-1 mRNA. Pure calreticulin accelerated the rate of GLUT-1 mRNA-probe degradation in vitro, whereas overexpression of calreticulin in vascular cells decreased significantly the total cell content of GLUT-1 mRNA and protein. The expression of calreticulin was augmented in vascular cells exposed to high glucose in comparison with low-glucose conditions. Similarly, increased expression of calreticulin was observed in aortae of diabetic Psammomys obesus in comparison with normoglycemic controls. These data suggest that CAE(2181-2190)-calreticulin complex, which is formed in VSMC and VEC exposed to hyperglycemic conditions, renders GLUT-1 mRNA susceptible to degradation. This interaction underlies the process of downregulation of glucose transport in vascular cells under high-glucose conditions.  相似文献   
38.
39.
We compared the cognitive and language development at 4, 14, 24, 36, 54 months, and 7 years of siblings of children with autism (SIBS-A) to that of siblings of children with typical development (SIBS-TD) using growth curve analyses. At 7 years, 40% of the SIBS-A, compared to 16% of SIBS-TD, were identified with cognitive, language and/or academic difficulties, identified using direct tests and/or parental reports. This sub-group was identified as SIBS-A-broad phenotype (BP). Results indicated that early language scores (14–54 months), but not cognitive scores of SIBS-A-BP and SIBS-A-nonBP were significantly lower compared to the language scores of SIBS-TD, and that the rate of development was also significantly different, thus pinpointing language as a major area of difficulty for SIBS-A during the preschool years.  相似文献   
40.
Neuropsychological functioning of 30 siblings of children with autism (AU-S), 28 siblings of children with mental retardation of (MR-S), and 30 siblings of children with developmental language delay (DLD-S) was compared. Two siblings, both AU-S, received diagnoses of pervasive developmental disorder (PDD). More siblings with cognitive disabilities were found in DLD-S than in AU-S. However, these differences disappeared after excluding diagnosed siblings or after accounting for family membership. In sum, despite the elevated incidence of PDD among AU-S, the neuropsychological functioning of the remaining siblings did not convey specific characteristics related to the genetic risk associated with autism, in contrast to the cognitive functioning of the DLD-S, which did reflect a genetic risk.  相似文献   
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