Values of tandem mass spectrometry in etiologic diagnosis of cerebral developmental retardation / 中华儿科杂志

<p><b>OBJECTIVES</b>To investigate the values of tandem mass spectrometry (MS/MS) in etiologic diagnosis and understanding therapeutic effect in cerebral developmental retardation, and to help patients in early diagnosis, treatment and favorable prognosis.</p><p><b>METHODS</b>One hundred and fifty-eight childhood patients with brain heteroplasia were tested from July 2004 to October 2006. The blood was collected on filter paper, punched and extracted into methanol solution with stable isotope labeled internal standards, then derivatized with butanolic-HCl. After preparation, the samples were analysed by tandem mass spectrometry. Eleven MS/MS-positive patients were further analyzed based on gas chromatography/mass spectrometry (GC/MS) analysis of urine, clinical course, and treatment outcome.</p><p><b>RESULTS</b>Eleven of 158 patients (7.0%) with inborn metabolic error were confirmed, including five with methylmalonic acidemia, two with propionic acidemia, one with ornithine transcarbamylase deficiency, one with maple syrup urine disease, one with phenylketonuria, and one with biotinidase deficiency. Among them, five were male, six were female, aged from 4 days to 21 months. The clinical manifestations were diverse, including mental developmental retardation or degradation (11 cases), convulsion (5 cases), coma (4 cases), vomiting (4 cases), malnutrition (4 cases), lethargy (3 cases), repeated infection (3 cases), hypotonia (2 cases), etc. Laboratory findings showed metabolic acidosis, hyperammonemia, hyperlactacidemia, anemia, etc. MRI findings of the brain showed cerebral atrophy, a pattern of bilateral T(2)W high signal intensity or/and T(1)W low signal intensity in cerebral white matter and multiple encephalomalacia or vesicular change, ect. In methylmalonic acidemia patients, the early onset with severe acidosis and coma have had a poor prognosis. Improvement was observed in 8 cases after treatment with vitamin B(12), L-carnitine, special milk, low-protein diet or biotin, etc. However 3 MMA patients died.</p><p><b>CONCLUSION</b>MS/MS was helpful for some patients in etiologic diagnosis and understanding therapeutic effect of cerebral developmental retardation. Early diagnosis and appropriate treatment are essential to improve the prognosis and prevent brain damage.</p>

Analysis of haplotype-based haplotype relative risk and transmission disequilibrium test in childhood absence epilepsy / 中华儿科杂志

<p><b>OBJECTIVE</b>Childhood absence epilepsy (CAE), a common form of idiopathic generalized epilepsy, accounts for 8% - 15% of all childhood epilepsies. A positive family history of epilepsy, a hereditary factor being one of the pathogeneses, is found in 15% - 44% of children with absence seizures. The phenotype of CAE is specific (including seizure forms and EEG), therefore it is suitable for genetic study. The purpose of this study was to confirm the linkage of childhood absence epilepsy to chromosome 8q24 in China.</p><p><b>METHODS</b>Twenty-nine trios families (a patient and his/her parents) as patient group and 10 normal trios families as control group were investigated for chromosome 8q24 by haplotype analysis with 5 microsatellite DNA markers (D8S554, D8S534, D8S1100, D8S1783, D8S1753). Genomic DNA was isolated from 4 ml human peripheral blood by using the conventional procedure, and then was treated using the PCR method. PCR products were analyzed by gene scan. Statistical methodology included haplotype-based haplotype relative risk (HHRR) and transmission disequilibrium test (TDT).</p><p><b>RESULTS</b>In this study, the polymorphism information content (PIC) of 5 microsatellite DNA markers were: 0.519, 0.828, 0.528, 0.654 and 0.772. HHRR showed D8S554(4) (chi(2) = 5.939, P < 0.05), D8S1100(3) (chi(2) = 5.081, P < 0.05), D8S1783(6) (chi(2) = 4.308, P < 0.05). TDT showed D8S554(4) (chi(2) = 4.46, P < 0.05), D8S1783(6) (chi(2) = 4, P < 0.05). In order to exclude false association results, the authors analyzed every family in detail. Four trios families transmitted allele D8S1783(6) to their offspring, and the same allele hasn't been found in controls. The further work showed that locus D8S1783 had transmission disequilibrium with CAE, the other two loci were a false association.</p><p><b>CONCLUSION</b>(1) Childhood absence epilepsy in the Chinese population may be linked to chromosome 8q24, the CAE gene is transmitted disequilibrium on locus D8S1783. Combined with other research results, we suppose that CAE gene may be in the ECA1 area on chromosome 8q24. (2) The CAE gene perhaps has a genetic heterogeneity in the population of different areas and different races. (3) HHRR and TDT seem to be the best statistical methods to do linkage disequilibrium study in the trios family.</p>

Examination of anti-HBx in sera from patients of chronic hepatitis B,liver cirrhosis and hepatocellular carcinoma and its clinical significance / 中华检验医学杂志

Objective To establish a method of detecting hepatitis B virus x antigen (HBxAg) and antibody to HBxAg (anti-HBx) and to demonstrate its clinical significance of HBxAg and anti-HBx in sera from patients of chronic hepatitis B (CHB),liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Methods Full length HBx gene was cloned into pET30a(+),a prokaryotic expression vector,named pET30a-X.It was transformed into Escherichia coli BL21 (DE3),followed the fusion protein of HBx-His was induced by IPTG.The purified fusion protein was used to immunize rabbit as an antigen to generate polyclonal antibody to HBx protein.The method of enzyme-linked immunosorbent assay (ELISA) was established by using purified fusion protein and generated antibody,which was used to detect HBxAg and anti-HBx in sera from patients of CHB,LC,HCC and normal healthy people.Results The positive rates of HBxAg/anti-HBx were 8.7%/10.4% for CHB,17.9%/40.6% for LC,and 9.8%/34.4% for HCC, respectively.In statistics,the positive rates of anti-HBx in LC and HCC were higher than that in CHB (P