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81.
Spinocerebellar ataxias in the Netherlands: prevalence and age at onset variance analysis 总被引:7,自引:0,他引:7
van de Warrenburg BP Sinke RJ Verschuuren-Bemelmans CC Scheffer H Brunt ER Ippel PF Maat-Kievit JA Dooijes D Notermans NC Lindhout D Knoers NV Kremer HP 《Neurology》2002,58(5):702-708
BACKGROUND: International prevalence estimates of autosomal dominant cerebellar ataxias (ADCA) vary from 0.3 to 2.0 per 100,000. The prevalence of ADCA in the Netherlands is unknown. Fifteen genetic loci have been identified (SCA-1-8, SCA-10-14, SCA-16, and SCA-17) and nine of the corresponding genes have been cloned. In SCA-1, SCA2, SCA3, SCA6, SCA7, SCA-12 and SCA-17 the mutation has been shown to be an expanded CAG repeat. Previously, the length of the CAG repeat was found to account for 50 to 80% of variance in age at onset. Because of heterogeneity in encoded proteins, different pathophysiologic mechanisms leading to neurodegeneration could be involved. The relationship between CAG repeat length and age at onset would then differ accordingly. METHOD: Based on the results of SCA mutation analysis in the three DNA diagnostic laboratories that serve the entire Dutch population, the authors surveyed the number of families and affected individuals per SCA gene, as well as individual repeat length and age at onset. Regression analysis was applied to study the relationship between CAG repeat length and age at onset per SCA gene. The slopes of the different regression curves were compared. RESULTS: On November 1, 2000, mutations were found in 145 ADCA families and 391 affected individuals were identified. The authors extrapolated a minimal prevalence of 3.0 per 100,000 (range 2.8 to 3.8/100,000). SCA3 was the most frequent mutation. CAG repeat length contributed to 52 to 76% of age at onset variance. Regression curve slopes for SCA-1, SCA2, SCA3, and SCA7 did not differ significantly. CONCLUSIONS: The estimated minimal prevalence of ADCA in the Netherlands is 3.0 per 100,000 inhabitants. Except for SCA6, the relationship between age at onset and CAG repeat expansion does not differ significantly between SCA-1, SCA2, SCA3, and SCA7 patient groups in our population, indicating that these SCA subtypes share similar mechanisms of polyglutamine-induced neurotoxicity, despite heterogeneity in gene products. 相似文献
82.
Mitchell LA Thomas PQ Zacharin MR Scheffer IE 《AJNR. American journal of neuroradiology》2002,23(9):1475-1481
BACKGROUND AND PURPOSE: Ectopic posterior pituitary lobe often occurs in children with growth hormone deficiency and is part of the spectrum associated with septo-optic dysplasia. Some cases of septo-optic dysplasia are caused by homozygous mutations in the homeobox gene HESX1, whereas heterozygous mutations are associated with milder phenotypes. To date, HESX1 is the only gene associated with ectopic posterior pituitary lobe. We describe an association between ectopic posterior pituitary lobe and periventricular heterotopia in four children without classic features of septo-optic dysplasia and suggest possible mechanisms on the basis of a review of pituitary embryology and recent molecular genetic advances. METHODS: Among 20 children with ectopic posterior pituitary lobe, four had associated periventricular heterotopia. We herein review the clinical and MR imaging findings of these four children. Mutation screening of HESX1 was performed in two. RESULTS: All four children had growth hormone deficiency. None had visual or neurologic disturbances. MR images showed a range of pituitary appearances, with scattered discrete periventricular heterotopia in each case. Other abnormalities were limited to small suprasellar lipomas and callosal dysgenesis. A heterozygous HESX1 mutation was present in one case. CONCLUSION: The coexistence of ectopic posterior pituitary lobe and periventricular heterotopia suggests they have a common underlying genetic basis that is due to gene expression at different locations and stages of development. The presence of a heterozygous HESX1 mutation in one case suggests this gene is important in the development of both ectopic posterior pituitary lobe and periventricular heterotopia and supports their place in the spectrum of septo-optic dysplasia. Further analysis of HESX1 and other genes in related developmental pathways will elucidate their roles in the development of both malformations. 相似文献
83.
Dexamethasone decreases the pro- to anti-inflammatory cytokine ratio during cardiac surgery 总被引:8,自引:2,他引:6
El Azab SR Rosseel PM de Lange JJ Groeneveld AB van Strik R van Wijk EM Scheffer GJ 《British journal of anaesthesia》2002,88(4):496-501
Background. Cytokines regulate inflammation associated withcardiopulmonary bypass (CPB). Pro-inflammatory cytokines maycause myocardial dysfunction and haemodynamic instability afterCPB, but the release of anti-inflammatory cytokines is potentiallyprotective. We studied the effects of dexamethasone on pro-and anti-inflammatory cytokine responses during coronary arterybypass grafting surgery. Methods. Seventeen patients were studied: nine patients receiveddexamethasone 100 mg before induction of anaesthesia (group1) and eight patients acted as controls (group 2). Plasma levelsof tumour necrosis factor (TNF)- 相似文献
84.
1临床资料患儿,女性,4岁。因间断性腹痛1月加重伴黑便15d,呕吐2d入院。患儿病前无明确外伤史,其母于入院前15d发现左膝部有损伤痕,已愈合,行腹部B超检查,提示肝胆肾正常,胰大小正常,边界清,实质回声均匀,主胰管不扩张,肝前区肝肾夹角及脾肾夹角可见53mm的液性暗区,内见肠管蠕动 相似文献
85.
Extracts of Monascusus Purpureus beyond Statins——Profile of Efficacy and Safety of the Use of Extracts of Monascus Purpureus 下载免费PDF全文
BIANCHI Antonio 《中国结合医学杂志》2005,(4)
Monascus purpureus is a fungus that has been tradi-tionally used in China for thousands of years to produce ricewine . Traditionally the fungus is used to ferment non-gluti-nous cooking of rice ,to produce a kind of famous red ricewine .Its main traditional indications consist of disordersdue to the accumulation of fats (nosologically linked withthe problems of stasis of circulation in traditional Chinesemedicine) ,liver disorders and some forms of tumor as ithelps i mprove the circulation of … 相似文献
86.
87.
Recent molecular insights into the human idiopathic epilepsies have suggested the central role of ligand-gated and voltage-gated ion channels in their etiology. So far, genes coding for sodium and potassium channel subunits as well as a nicotinic cholinergic receptor subunit have been identified for Mendelian idiopathic epilepsies. In vitro and in vivo studies of mutations demonstrate functional changes, allowing new insights in mechanisms underlying hyperexcitability. Similarly, spontaneous murine epilepsy models have been associated with calcium channel molecular defects. The major challenge before us in understanding the genetics of the epilepsies is to identify genes for common forms of epilepsy following complex inheritance. Once such genes are discovered, the gene-gene-environmental interactions producing specific epilepsy syndromes can be explored. 相似文献
88.
89.
NC de Bruin KA van Velthoven M de Ridder T Stijnen RE Juttmann HJ Degenhart HK Visser 《Archives of disease in childhood》1996,74(5):386-399
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores. 相似文献
90.
Leaf AN Wolf BC Kirkwood JM Haselow RE 《Medical oncology (Northwood, London, England)》2000,17(1):47-51
This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of
inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required
to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose
of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There
were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity
of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual. 相似文献