-
[show abstract]
[hide abstract]
ABSTRACT: To delineate the phenotype and genotype in Chinese children with type I Alexander disease (AxD) and the parental origin of de novo glial fibrillary acidic protein (GFAP) mutations. Twenty-two children with clinically diagnosed type I AxD were followed up for 1.66-6.62 years. Allele-specific PCR was used for the analysis of parental origin of the allele harboring the de novo mutation. Phenotype of these patients were consistent with type I AxD described in other population, with developmental delay (motor delay in 81.82%, cognitive delay in 63.64%), macrocephaly (100%), seizures (95.45%), paroxysmal deterioration (27.27%) and typical brain magnetic resonance imaging (100%). Progression was slower than reported. At 8.55 years of age (5.29-13.25), all patients who underwent the second follow-up were alive. Eleven heterozygous missense mutations of GFAP were identified in 21 patients, with three novel mutations. Reported hot spot mutations, p.R79, p.R239 and p.R88, were also identified in Chinese patients. Mutations were de novo in all but one case. The mother of a proband was demonstrated to be a presymptomatic patient with type II AxD with a p.R79H mutation. Ninety percent of de novo mutations were on the paternal allele demonstrated by allele-specific PCR. This is the largest follow-up study on Chinese children with AxD. The phenotypes of these patients are consistent with reports in other populations. GFAP mutations were identified in 95.46% of Chinese children with clinically diagnosed type I AxD. Our data suggested a male germ-line transmission.Journal of Human Genetics advance online publication, 31 January 2013; doi:10.1038/jhg.2012.152.
Journal of Human Genetics 01/2013; · 2.57 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To explore HEPACAM mutations in a Chinese family with megalencephalic leukoencephaloptathy with subcortical cysts (MLC).
Genomic DNA samples were extracted from peripheral blood of the proband and her parents. All exons and exon-intron boundaries of HEPACAM and MLC1 were amplified in the MLC family by polymerase chain reaction (PCR) followed by direct DNA sequencing.
Two heterozygous mutations of HEPACAM located in exon 2, c.203A > T(p.K68M) and c.395C > A(p.T132N), were identified in the proband. The proband's mother had the heterozygous mutations c.203A > T(p.K68M), and her father had the heterozygous mutation-c.395C > A(p.T132N). There was no variation found in MLC1 gene.
The proband was heterozygous compound MLC patient carrying on one allele with the c.203A > T(p.K68M) mutation inherited from her mother, and the other allele with the c.395C > A(p.T132N) mutation inherited from her father. The parents both are heterozygous carriers with normal phenotype. The disease-causing gene for this family was resulted in HEPACAM mutation other than MLC1 mutation.
Zhonghua er ke za zhi. Chinese journal of pediatrics 12/2012; 50(12):895-8.
-
[show abstract]
[hide abstract]
ABSTRACT: Study Design. The expression of netrin-1 and its deleted in colorectal cancer (DCC) receptor were investigated in human lumbar discs using immunohistochemistry.Objective. To investigate the expression of netrin-1 and DCC receptor in human diseased and healthy lumbar intervertebral discs (IVDs) and to clarify the correlation between netrin-1 expression and the degree of neurovascular ingrowth.Summary of Background Data. Previous studies have showed neurovascular ingrowth into the inner regions of degenerated IVD, and suggested the ingrowth may contribute to discogenic low back pain. Netrin-1 is an axon guidance molecule which regulates axons seeking their final targets, and has been identified involved in a variety of pathological conditions, so is its DCC receptor. However, the role of netrin-1 in diseased IVDs remains unknown.Methods. Thirty-five diseased IVD specimens were collected from 34 patients with different lumbar diseases during posterior lumbar interbody fusion. 8 normal discs were obtained at autopsy as control. Using polyclonal or monoclonal antibody, the disc slides were immmunostained to detect the expression and distribution of netrin-1, the DCC, the neuronal marker(neurofilament), and the vascular endothelial cell marker(CD34).Results. Netrin-1 and DCC immunopositive cells distributed substantially from the annulus fibrosus (AF) to the nucleus pulposus (NP), and the immunopositivity was detected in the disc cells, endothelial cells and granulation tissue cells in the diseased discs. The percentage of netrin-1 positive disc cells of the NP was more than that of the AF. The expression of netrin-1 and DCC was weak in the normal discs. A significant positive correlation between the percentage of netrin-1 immunopositive disc cells and neurovascular scores was found.Conclusion. The increased expression of Netrin-1 and DCC in diseased IVDs compared with controls suggested they might play an important role in the process of neurovascular ingowth.
Spine 05/2012; · 2.08 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To delineate the phenotype and genotype characteristics in 12 Chinese children with Alexander disease (AD), which is helpful for the molecular diagnosis and genetic counseling in China.
Clinical diagnosis of AD was based on MRI criteria proposed by van der Knaarp in 2001. Included AD patients were followed up for 0.50 - 3.67 years. Mutations in GFAP were detected by DNA sequencing.
The 12 cases of AD were clinically diagnosed. Age of first visit was 4.87 years (0.75 - 12.00 years), with 3 types of chief complaints: developmental delay in 3, recurrent seizures in 7, unable to walk after falling in 2. Average head circumference was 52.34 cm (44 - 58 cm), which larger than age-matched average by 6.45% (1.80% - 13.95%). On the first visit, scaling according to Gross motor functional classification system (GMFCS) was performed, with GMFCSI in 8, II in 3, V in 1. Mild to severe cognitive dysfunction were found in 8, and seizures in 11 cases. The 12 patients were followed up for 0.50 - 3.67 years, their motor and cognitive function remained stable. Episodic aggravations provoked by fever or falling were observed in 5 cases (41.67%). Heterozygous missense mutations of GFAP were detected in 12 patients. All mutations were de novo; 3 out of 10 mutations identified were novel. R79 and R239 were hot mutations, which was consistent with previous reports. Mutations were located in exon 1 in 8 cases.
The phenotype in these patients is characterized by slower progression compared with reports from other population and high incidence of seizures. And episodic aggravations provoked by fever or falling were more common. The genotype characteristics are consistent with previous reports. The results of this research expanded the number of patients with Alexander disease found to have GFAP coding mutations in China.
Zhonghua er ke za zhi. Chinese journal of pediatrics 05/2012; 50(5):371-5.
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of current study was to elucidate whether aquaporin-9 (AQP9) expression was involved in the progression of bone loss induced by microgravity. We used the hind-limb suspension (HLS) mice model to simulate microgravity and induce bone loss. It was found that HLS exposure decreased femur bone mineral density (BMD), and enhanced femur AQP9 mRNA and protein levels. Then, the relationship between AQP9 mRNA expression and BMD was studied and it was showed that femur AQP9 mRNA level was negatively related to femur BMD in mice exposed to HLS. We sought to exam the function of AQP9 in the femur using the AQP9-null mice. It was found that AQP9 knockout attenuated bone loss and inhibited osteoclastogenesis under the condition of HLS exposure, but had no similar effect on bone under normal physiological conditions. In addition, it was found that exposure to simulated hypergravity or exercise training, main countermeasures against microgravity, reduced AQP9 mRNA and protein levels in femur of mice. Moreover, it was found that both aging and estrogen deprivation, another two risk factors of bone loss, had no significant effect on femur AQP9 expression. In conclusion, AQP9 plays an important role in the development of microgravity-induced bone loss, and may be a potential target for the prevention or management of microgravity-induced bone loss.
Biochemical and Biophysical Research Communications 02/2012; 419(4):774-8. · 2.48 Impact Factor
-
Yuwu Jiang,
Yuehua Zhang,
Pingping Zhang,
Tian Sang,
Feng Zhang,
Taoyun Ji,
Qionghui Huang,
Han Xie,
Renqian Du,
Bin Cai,
Haijuan Zhao,
Jingmin Wang, Ye Wu,
Husheng Wu,
Keming Xu,
Xiaoyan Liu,
Piu Chan,
Xiru Wu
[show abstract]
[hide abstract]
ABSTRACT: While pathogenic copy number variations (CNVs) in 15q11.2 were recently identified in Caucasian patients with idiopathic generalized epilepsies (IGEs), the epilepsy-associated gene(s) in this region is/are still unknown. Our study investigated whether the CNVs in 15q11.2 are associated with childhood absence epilepsy (CAE) in Chinese patients and whether the selective magnesium transporter NIPA2 gene affected by 15q11.2 microdeletions is a susceptive gene for CAE. We assessed IGE-related CNVs by Affymetrix SNP 5.0 microarrays in 198 patients with CAE and 198 controls from northern China, and verified the identified CNVs by high-density oligonucleotide-based CGH microarrays. The coding region and exon-intron boundaries of NIPA2 were sequenced in all 380 patients with CAE and 400 controls. 15q11.2 microdeletions were detected in 3 of 198 (1.5%) patients and in no controls. Furthermore, we identified point mutations or indel in a heterozygous state of the NIPA2 gene in 3 out of 380 patients, whereas they were absent in 700 controls (P = 0.043). These mutations included two novel missense mutations (c.532A>T, p.I178F; c.731A>G, p.N244S) and one small novel insertion (c.1002_1003insGAT, p.N334_335EinsD). No NIPA2 mutation was found in 400 normal controls. We first identified that NIPA2, encoding a selective magnesium transporter, is a susceptible gene of CAE, and 15q11.2 microdeletions are important pathogenic CNVs for CAE with higher frequency in Chinese populations than that previously reported in Caucasians. The haploinsufficiency of NIPA2 may be a mechanism underlying the neurological phenotypes of 15q11.2 microdeletions.
Human Genetics 02/2012; 131(7):1217-24. · 5.07 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Size-resolved particulate matter in the three size ranges (0.2-0.5 μm, 0.5-1.0 μm, and 1.0-2.5 μm) were collected at a roadside site in Beijing during and after the 2008 Olympic Games. The concentrations of PM mass, 14 elements, 3 major inorganic ions, and carbonaceous species were determined. The main contributors to PM(2.5) were crustal sources, vehicle emissions, secondary aerosol formation along with coal combustion, biomass from burning, and industrial processes, with vehicle emissions contributing more to roadside PM(2.5) than in the urban areas. The peaks at 0.5-1.0 μm in summer for PM mass and inorganic ions were most likely due to secondary aerosol formation, whereas the peaks at 0.2-0.5 μm in winter for PM mass and some elements were probably attributed to combustion from heating sources. The temporary control measures applied during the Olympics showed different effects on various emission sources and chemical species.
Environmental pollution (Barking, Essex: 1987) 02/2012; 161:215-21. · 3.43 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Clinical findings, pathological features and tripeptidyl peptidase 1 (TPP1) activity and genetic mutation analysis data of nine patients affected with the late-infantile form of neuronal ceroid lipofuscinoses (LINCL) in China are systematically reviewed with long-term follow-up. The patients were enrolled if curvilinear bodies were found on lymphocyte, skin or muscle specimens' examination, and/or reduction of tripeptidyl peptidase 1 (TPP1) activity were detected. CLN2 gene mutation were tested in five patients. The patients have onset age of 2-3.5 years, and most of them initially present partial seizure, and then progressed to deteriorated mental function, refractory myoclonic seizures, impaired vision, and ataxia with cerebellar atrophy. Discrete small vacuolated lymphocytes are found in 5-10% lymphocytes in 5 patients examined. Curvilinear bodies were found in vacuolated lymphocytes, in skin and muscle tissues. Tripeptidyl peptidase 1 (TPP1) activities are reduced in 5 patients with different CLN2 gene mutation. Detection of vacuolated lymphocytes may be a screen method for LINCL, ultrastructural examination of lymphocytes, combined with TPP1 activity assay, allowing for a definite and faster diagnosis and classification with minimal invasion.
Brain & development 01/2012; 34(9):739-45. · 1.74 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is a rare autosomal recessive disease. Affected individuals are invariably compound heterozygous for two mutations in DARS2. No reports of LBSL patients have been published in the mainland of China. The aim of this study was to explore the clinical and genetic features of a family with LBSL, which may contribute to definite diagnosis, genetic counseling and prenatal diagnosis of this rare disease in China.
Clinical data of the proband and other family members as well as DNA samples were collected. Clinical features including symptoms, signs and cranial MRI were analyzed. All 17 exons and exon-intron boundaries of DARS2 gene were amplified with polymerase chain reaction (PCR) and directly sequenced for genomic DNA. The mutation was proved by DNA restriction enzyme digestion of PCR-amplified fragments.
(1) The clinical features of patient with LBSL included slowly progressive cerebellar ataxia and spasticity, the neurologic dysfunction involving the legs more than the arms, and with characteristic abnormalities observed on brain and spinal cord MRI. (2) Two mutations were identified, one was a novel missense mutation [c.665 G > A(p.Gly222Asp)] in DARS2 gene exon 8, the other (c.228-16 C > G) was in DARS2 gene intron 3.
This is the first report on LBSL patient and DARS2 mutation in China. p.Gly222Asp mutation is a novel mutation not reported around the world yet.
Zhonghua er ke za zhi. Chinese journal of pediatrics 01/2012; 50(1):50-5.
-
Han Xie,
Jingmin Wang,
Ajit Singh Dhaunchak,
Jing Shang,
Liping Kou,
Mangmang Guo, Ye Wu,
Qiang Gu,
David Colman,
Xiru Wu,
Yuwu Jiang
[show abstract]
[hide abstract]
ABSTRACT: Megalencephalic leukoencephalopathy with subcortical cysts (MLC, MIM# 604004) is an autosomal recessive inherited disease mostly resulting from MLC1 mutations. In this study, we finished the functional analysis of MLC1 mutations identified recently in Chinese patients, including five newly described missense mutations (R22Q, A32V, G73E, A275T, Y278H), one known nonsense mutation (Y198X), and two known missense mutations (S69L, T118M). We found MLC1(wt) was localized to the cell periphery, whereas mutant R22Q, A32V, G73E, S69L and T118M were trapped in the lumen of endoplasmic reticulum (ER) when we transfected the wild-type and mutant MLC1 in U373MG cells. Compared to wild type, the mutant G73E, T118M, Y198X and A275T transcript decreased and all mutants except R22Q had lower protein expression in transfected U373MG cells. Therefore, we propose that all these eight MLC1 mutations had functional effect either on their protein/mRNA expression, or on their intracellular protein localization, or both.
PLoS ONE 01/2012; 7(3):e33087. · 4.09 Impact Factor
-
Zhi-xiao Yang,
Hui Xiong,
Yue-hua Zhang,
Xin-Hua Bao,
Yu-wu Jiang, Ye Wu,
Shuang Wang,
Xing-zhi Chang,
Jiong Qin,
Qing Lin,
Xi-ru Wu
[show abstract]
[hide abstract]
ABSTRACT: To investigate and analyze the clinical manifestations, classification, therapeutic approaches and follow-up of myasthenia gravis (MG) in children in order to improve its management and prognosis.
Clinical information of 135 children with MG, who were diagnosed between January 1993 to January 2008, were collected and retrospectively analyzed. And prospective following-up of these patients were conducted.
Among the 135 cases, 59 were males and 76 females, giving the ratio of M/F around 1:1.3. Totally, 115 cases (85.2%) were type I MG (ocular type), of which only 4.2% developed to generalized type during the subsequent clinical course. Type II MG (generalized type)was found in 18 cases (13.4%) and type III MG in two cases(1.5%). The onset age ranged from 5 month to 15 years, with 50.3% before three years and 80.7% before seven years. Upper respiratory tract infection was presented in 26.7% (36/135) of the sick children before the onset of MG. Among the 106 children being followed up, recurrence of the disease identified in 50.9% and the number of relapse ranged from 1 to 9. Altogether, 40.19% (43/106) of the cases were positive for anti-acetylcholine receptor antibodies (AchR-Ab) on the initial examination, and the AchR-Ab postitive rate showed no difference among different clinical subtypes and states. However, during the follow-up, 53% (9/17) of the recurrent cases, who were negative at the first onset, turned to be positive, and 37.97% (30/79) were positive for repetitive nerve stimulation in electromyogram test. There were 71 % (45/63) of all the cases showed reduced levels of CD4+ and/or CD3+ and/or CD8+. Thymus proliferation was found in 5.93% (8/135) through CT scan and thymoma in 1.48% (2/135). Steroids and anti-cholinesterase administration were effective in most cases with good prognosis.
Childhood MG, mainly type I, is relatively common in China, with specific characteristics which are different from western patients or adult MG in morbidity, sex distribution, progress, laboratory examination and treatment. The prevalence of myasthenia gravis crisis and mortality rate in MG children is low, and few are accompanied with thymoma. Most MG cases have a satisfied prognosis and few have neuropsychic sequela.
Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences 06/2011; 43(3):455-9.
-
[show abstract]
[hide abstract]
ABSTRACT: To investigate the association of the polymorphisms of methionine metabolism genes and the phenotype of X-linked adrenoleukodystrophy (X-ALD) and clinical severity.
The clinical information of 120 X-ALD patients were analyzed and three genetic variants involved in the methionine metabolism, including cystathionine beta-synthase (CBS) c.844_855ins68, 5-methyltetrahydrofolate-homocysteine-S-methyltransferase (MTR) c.2756A to G, and transcobalamin 2 (TC2) c.776 C to G were analyzed by polymerase chain reaction and sequencing. The association between these polymorphisms and phenotype of X-ALD was studied.
The frequency of GG genotype of the TC2 c.776 C/G was higher in patients with central nervous system(CNS) demyelination than in controls (P= 0.012). However, the other two polymorphisms did not show any significant associations with the phenotypes.
The GG genotype of TC2 c.776 C/G may contribute to X-ALD phenotype.
Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics 06/2011; 28(3):279-82.
-
Xuerong Leng, Ye Wu,
Xuemin Wang,
Yanxia Pan,
Jingmin Wang,
Jiao Li,
Li Du,
Lifang Dai,
Xiru Wu,
Christopher G Proud,
Yuwu Jiang
[show abstract]
[hide abstract]
ABSTRACT: Vanishing white matter disease (VWM) is the first human hereditary disease known to be caused by defects in initiation of protein synthesis. Gene defects in each of the five subunits of eukaryotic translation initiation factor 2B (eIF2B α-ɛ) are responsible for the disease, although the mechanism of the pathogenesis is not well understood. In our previous study, four novel eIF2Bɛ mutations were found in Chinese patients: p.Asp62Val, p.Cys335Ser, p.Asn376Asp and p.Ser610-Asp613del. Functional analysis was performed on these mutations and the recently reported p.Arg269X. Our data showed that all resulted in a decrease in the guanine nucleotide exchange (GEF) activity of the eIF2B complex. p.Arg269X and p.Ser610-Asp613del mutants displayed the lowest activity, followed by p.Cys335Ser, p.Asn376Asp and p.Asp62Val. p.Arg269X and p.Ser610-Asp613del could not produce stable eIF2Bɛ, leading to almost complete loss-of-function. No evidence was obtained for the three missense mutations in changes in eIF2Bɛ protein level or eIF2BɛSer(540) phosphorylation, and disruption of holocomplex assembly, or binding to eIF2. All patients in our study had the classical phenotype. p.Asp62Val and p.Asn376Asp mutations caused only mildly decreased GEF activity, were probably responsible for relatively mild phenotype in cases of classical VWM.
Journal of Human Genetics 02/2011; 56(4):300-5. · 2.57 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Lysosomal storage diseases are a group of inherited disorders caused by deficiency of lysosomal enzymes or structural components. The manifestations of lysosomal storage diseases are complicated due to different enzyme deficiency. It has been reported that a range of metabolic diseases resulting in abnormal accumulation of metabolic byproducts may exhibit abnormal cytoplasmic vacuolation of lymphocytes. The aim of this study was to elicit the usefulness of vacuolated peripheral lymphocytes detection in screening and diagnosis of lysosomal storage diseases.
Clinical data of 42 patients who underwent microscopic and electron microscopic examination of peripheral blood specimens in our department were retrospectively evaluated between January 2008 and December 2009.
Forty-two patients with the suspected lysosomal storage diseases were included, these patients presented with motor and developmental retardation and/or regression. Seizure occurred in 32 patients. Hepatosplenomegaly were found in 4 patients. Three patients presented with declined visual acuity. Atrophy and/or abnormal signals were detected on cranial CT/MRI images in 24 patients. Blood biochemical tests were normal. Serum levels of ammonia, lactic acid and pyruvate were normal. Serum amino acid profiles and urinary organic acid profiles were normal. Serum fatty acid profiles were normal. Vacuolated lymphocytes were detected on microscopic examination of blood film in 14 patients, and 8 of these patients were confirmed to have lysosomal storage disease. Curvilinear body was found on electronic microscopic examination of peripheral lymphocytes specimens in 4 patients, confirming the diagnosis of neuronal ceroid lipofuscinosis. In 3 of these 4 patients, curvilinear body were also found on electronic microscopic examination of skin and/or muscle specimens. Enzyme analysis confirmed the diagnosis of metachromatic leukodystrophy in one patient and Pompe's disease in another patient. Typical pathological changes were found on the examination of bone marrow in 2 patients with normal acid sphingomyelinase activity. So the patients were diagnosed with Niemann-Pick disease type C. The diagnosis of other 6 patients with vacuolated lymphocytes was unknown.
Because of its usefulness and minimal invasiveness, vacuolated peripheral lymphocytes examination should be a screening test for lysosomal storage disease. As for patients with suspected neuronal ceroid lipofuscinosis, electron microscopic examination of peripheral lymphocyte specimens may provide specific clues to the final diagnosis.
Zhonghua er ke za zhi. Chinese journal of pediatrics 02/2011; 49(2):135-8.
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the value of cryptococcal latex agglutination test in the diagnosis and treatment of cryptococcal meningitis in children.
The clinical data of 10 children with cryptococcal meningitis were retrospectively studied. Cryptococcal meningitis was confirmed based on clinical manifestations, India ink stain, cryptococcal latex agglutination test or cryptococcal culture. The outcome of antifungal treatment and the changes of latex agglutination test titer were followed up for 2 to 4 years.
Latex agglutination test and/or India ink stain were positive (titer 1 : 64-1 : 1024) in 8 patients in the first examination of cerebrospinal fluid. In the other 2 patients, latex agglutination test was positive (titer 1 : 256) in the fourth examination of cerebrospinal fluid in one, and India ink stain was positive in the eleventh examination in the other. After antifungal treatment, six patients were cured, two patients died, and two patients were lost to follow-up. The positive cryptococcal latex agglutination test (titer 1 : 2-1 : 16) was seen respectively in six, three, two and one cured patients 6 months, 1 year, 2 years and 4 years later.
The cryptococcal latex agglutination test of cerebrospinal fluid is valuable for the quick and early diagnosis of cryptococcal meningitis; however, the decision of withdrawal of antifungal treatment should not rely on the results of the test.
Zhongguo dang dai er ke za zhi = Chinese journal of contemporary pediatrics 02/2011; 13(2):115-8.
-
[show abstract]
[hide abstract]
ABSTRACT: Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an autosomal, recessively inherited disease caused by mutations in the MLC1 gene. Most of the previously published studies have been carried out in ethnic populations other than the Chinese. In this study, the analysis of clinical features and MLC1 mutation screening were performed in 13 Chinese patients for the first time. A total of 10 MLC1 mutations were identified in these patients, including five novel missense mutations (c.65G>A, p.R22Q; c.95C>T, p.A32V; c.218G>A, p.G73E; c.823G>A, p.A275T; c.832T>C, p.Y278H), one novel splicing mutation (c.772-1G>C in IVS9-1), one novel small deletion (c.907_930del, p.V303_L310del), one known nonsense mutation (c.593delCTCA, p.Y198X) and two known missense mutations (c.206C>T, p.S69L; c.353C>T, p.T118M). Mutation c.772-1G>C in IVS9-1, accounting for 27.3% (3/11) of the total number of genetically confirmed patients found in this study, is thus a putative hot-spot mutation in the present study group. The existence of a unique MLC1 mutation spectrum in Chinese MLC patients was shown. A systemic study to assess the mutation spectra in different populations should be undertaken.
Journal of Human Genetics 12/2010; 56(2):138-42. · 2.57 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The developing brain undergoes major reorganization in response to early environmental changes. The elevated excitation that allows the neonatal brain to develop quickly also makes it highly vulnerable to age-specific seizures that can cause lifelong cognitive and neurological disability. However, it is not yet clear how seizures interfere with the developmental program and how epileptogenesis actualize. Here, by using an in vitro model, we report a global abnormal status of cortical cells after epileptiform activity was induced: more NR2B is targeted on the neuronal surface with less NR2A. Dendrotoxicity including dendritic beading, distortion and simplification of dendritic branching patterns were observed. Early-life seizure-like insults also exert effects on the excitatory synaptic size and interactions between PSD-95 and NR2A or NR2B receptor subunits. Our findings support an abnormal development or, worse, cellular degeneration that resembles immature cells, which may enlighten better understanding of the pathological mechanism of early-life seizures and its related injury.
International journal of developmental neuroscience: the official journal of the International Society for Developmental Neuroscience 10/2010; 28(6):455-63. · 2.03 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Jacobsen syndrome (JBS) is a haploinsufficiency syndrome caused by partial deletion of the long arm of chromosome 11. It is characterized by developmental delay (DD)/mental retardation (MR), physical growth retardation, facial dysmorphism, visceral malformations and thrombocytopenia. We report two JBS patients from China out of a total of 451 patients with unexplained DD/MR. The genotypes of these patients were compared with earlier reported patients in North America and Europe. Both patients presented with severe DD, microcephaly and facial dysmorphism; one patient had a low birth weight, congenital heart disease and structural brain abnormalities. Neither patient was thrombocytopenic at the time of diagnosis. The two deletions were 4.1 and 12.8 Mb. The 4.1 Mb deletion is the smallest of all pathogenic regions earlier reported in JBS. Therefore, the critical region underlying DD/MR might be located in the distal portion of the chromosomal segment within 4.1 Mb of the telomere. Candidate genes for DD/MR in this region include SNX19, THYN1, OPCML, NCAPD3 and NTM. One of the critical regions for craniofacial abnormalities may be within 130.3-134.4 Mb in chromosome 11q. Further analysis of Chinese JBS patients would elucidate the relation of phenotype to genotype further.
Journal of Human Genetics 08/2010; 55(8):486-9. · 2.57 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Wolf-Hirschhorn syndrome (WHS) results from the partial deletion of 4p. This study aimed to identify and fine map the chromosome deletion regions of Chinese children with Wolf-Hirschhorn syndrome among the developmental delay/mental retardation (DD/MR) patients.
We analyzed the relationship of phenotype and genotype. Inclusion criteria were: moderate to severe DD/MR, no definite perinatal brain injury, and no trauma, toxication, hypoxia, infection of central nervous system; routine karyotyping was normal, no evidence of typical inherited metabolic disorder or specific neurodegenerative disorders from cranial neuro-imaging and blood/urinary metabolic diseases screening; no mutation of FMR1 in male patients, no typical clinical manifestation of Rett syndrome in female patients. Multiplex ligation-dependent probe amplification (MLPA) and Affymetrix genome-wide human SNP array 6.0 assays were applied to accurately define the exact size of subtelomeric aberration region of four WHS patients.
All four WHS patients presented with severe DD, hypotonia and microcephaly, failure to thrive, 3/4 patients with typical facial features and seizures, 2/4 patients with congenital heart defects and cleft lip/palate, 1/4 patients with other malformations. The length of the deletions ranged from 3.3 Mb to 9.8 Mb. Two of four patients had "classic" WHS, 1/4 patients had "mild"-to-"classic" WHS, and 1/4 patients had "mild" WHS.
WHS patients in China appear to be consistent with those previously reported. The prevalence of signs and symptoms, distribution of cases between "mild" and "classic" WHS, and the correlation between length of deletion and severity of disease of these patients were all similar to those of the patients from other populations.
Chinese medical journal 07/2010; 123(13):1663-7. · 0.86 Impact Factor
-
Ye Wu,
Taoyun Ji,
Jingmin Wang,
Jing Xiao,
Huifang Wang,
Jie Li,
Zhijie Gao,
Yanling Yang,
Bin Cai,
Liwen Wang,
Zhongshu Zhou,
Lili Tian,
Xiaozhu Wang,
Nan Zhong,
Jiong Qin,
Xiru Wu,
Yuwu Jiang
[show abstract]
[hide abstract]
ABSTRACT: Subtelomeric imbalance is widely accepted as related to developmental delay/mental retardation (DD/MR). Fine mapping of aberrations in gene-enriched subtelomeric regions provides essential clues for localizing critical regions, and provides a strategy for identifying new candidate genes. To date, no large-scale study has been conducted on subtelomeric aberrations in DD/MR patients in mainland China.
This study included 451 Chinese children with moderate to severe clinically unexplained DD/MR. The subtelomere-MLPA (multiplex ligation dependent probe amplification) and Affymetrix human SNP array 6.0 were used to determine the subtelomeric copy number variations. The exact size and the breakpoint of each identified aberration were well defined.
The submicroscopic subtelomeric aberrations were identified in 23 patients, with a detection rate of 5.1%. 16 patients had simple deletions, 2 had simple duplications and 5 with both deletions and duplications. The deletions involved 14 different subtelomeric regions (1p, 2p, 4p, 6p, 7p, 7q, 8p, 9p, 10p, 11q, 14q, 15q, 16p and 22q), and duplications involved 7 subtelomeric regions (3q, 4p, 6q, 7p, 8p, 12p and 22q). Of all the subtelomeric aberrations found in Chinese subjects, the most common was 4p16.3 deletion. The sizes of the deletions varied from 0.6 Mb to 12 Mb, with 5-143 genes inside. Duplicated regions were 0.26 Mb to 11 Mb, with 6-202 genes inside. In this study, four deleted subtelomeric regions and one duplicated region were smaller than any other previously reported, specifically the deletions in 11q25, 8p23.3, 7q36.3, 14q32.33, and the duplication in 22q13. Candidate genes inside each region were proposed.
Submicroscopic subtelomeric aberrations were detected in 5.1% of Chinese children with clinically unexplained DD/MR. Four deleted subtelomeric regions and one duplicated region found in this study were smaller than any previously reported, which will be helpful for further defining the candidate dosage sensitive gene associated with DD/MR.
BMC Medical Genetics 05/2010; 11:72. · 2.33 Impact Factor
