1.A new MFN2 gene mutation resulting in hereditary motor and sensory neuropathy type 6, a family report
He Lü ; Daojun HONG ; Wurong LI ; Zhaoxia WANG ; Yun YUAN
Chinese Journal of Neurology 2011;44(10):702-705
ObjectiveTo report clinical, pathological and molecular genetic features in a Chinese family with hereditary motor and sensory neuropathy type 6. MethodsThe index case is a 15 years old boy.He developed progressive distal limb weakness at the age of 5.The disease deteriorated slowly,accompanied with contracture of achilles' tendon. At the age of 11 years old he suffered from decrease of visual acuity. At the age of 12, he found the muscular atrophy of both hands without sensory disturbances.Visual evoked potential revealed prolonged latency of bilateral P100. Ophthalmological examination showed bilateral optic atrophy. His mother had the similar symptoms at the age of 7 and reduced visual acuity at the age of 10. Nerve conduction velocity revealed in both pat1ents no compound motor and sensory nerve action potentials in most nerves or slightly reduced nerve conduction velocities with severely reduced amplitudes of the compound motor and sensory nerve action potentials. Sural nerve biopsy was performed on the proband.The sequence of MFN2 gene was analyzed in DNA from the index, his mother and 100 healthy controls.ResultsSural nerve biopsy revealed severe loss of myelinated fibers with few regenerating clusters.Ultrapathological examination showed a few of atypical bulbs of myelinated fibers, occasionally regenerating clusters, mitochondrial swelling and aggregation in a few of axons. A new mutation of W740R mutation in MFN2 gene has been identified in the index case, her mother, but not in 50 healthy controls. Conclusions A novel MFN2 gene mutation result in hereditary motor and sensory neuropathy type 6.Mild visual loss appeares after the lesion of spinal nerves. Demyelination of peripheral nerve appears in the disease.
2.Hot spot mutations in electron transfer flavoprotein dehydrogenase gene of riboflavin responsive lipid storage myopathy in 20 Chinese families
Yun WANG ; Danhua ZHAO ; Daojun HONG ; Zhaoxia WANG ; Yun YUAN
Chinese Journal of Neurology 2011;44(5):309-313
Objective To report the spectrum of electron transfer flavoprotein dehydrogenase (ETFDH)gene mutations in 20 Chinese RR-LsM families.Methods Twenty-four RR-LSM patients in the First Hospital of Peking University from January 2003 to May 2010 were collected and the clinical characteristics were analyzed.These patients came from 20 families in North Mainland China.Sixteen families had 1 patient each.and the other 4 families had 2 patients.ETFDH gene analysis was performed in all patients,11 family members and 100 healthy controls.Results The mean onset age was(27.9±9.9)years.The main symptoms were limb weakness(21,87.5%),dysmasesia(15,62.5%),neck weakness (14,58.3%)and myalgia(14,58.3%).Eighteen patients had high level of acyleamitine.Fifteen of 17patients had glutaric aciduria.Seventeen ETFDH mutations,including 13 missense mutations,2 splice mutations,and 2 nonsense mutations,were identified in 19 families:c.998A>G,c.1450T>C,c.1703T>C,c.1717C>T,c.821G>A,c.643G>A,c.251C>T,c.1763A>T,c.IVS7+2T>C and c.IVS6+1G>A were Hovel mutations which were not found in 100 healthy controls.Nine families had the mutation of c.770A>G(P.Y257C)and 5 families had the mutation of c.1227A>C(P.L409F).Conclusions The numerous novel mutations in ETFDH gene indicate that Chinese RR-LSM might have special mutation pattern.c.770A>G(P.Y257C)and c.1227A>C(p.L409F)may be hot spot mutations in North Mainland China.
3.Affected muscle fibers in Nonaka myopathy with endoplasmic reticulum stress
Juanjuan CHEN ; Danhua ZHAO ; Zhaoxia WANG ; Daojun HONG ; Yun YUAN
Chinese Journal of Neurology 2012;45(1):11-15
ObjectiveTo investigate the characteristic of pathology in Chinese patients with Nonaka myopathy.MethodsThirteen patients (7 males and 6 females) diagnosed with Nonaka myopathy in our laboratory from January 2002 to March 2011 were included in this study.Their mean age was 39.5 years old and the mean duration of illness was 4.15 years.The most common symptoms were weakness of raising feet with sparing of quadriceps femoris muscles in the early stage of disease.One patient presented the initial symptoms of upper limb weakness. Muscles biopsies were obtained from all these 13 patients. Histology study including immunohistochemical (IHC) staining with antibody against amyloid 3,phosphorylated tau protein,ubiquitin,glucose-regulated protein of molecular weight 78 000(GRP78),calnexin,caspase-12and Bax were performed.Skeletal muscle samples from 3 chronic fatigue syndrome patients,2 myofibrillar myopathy patients were used for control in the IHC staining. All coding exons of uridinediphospho-N-acetylglucosamine 2-epimerase gene were directly sequenced in genomic DNA from these patients.Results The main pathological changes of tibialis anterior muscle in 12 cases were muscle dystrophy with rimmed vacuoles.The rimmed vacuoles were positive for anti-β-amyloid,tau protein and ubiquitin in IHC studies.In the atrophy fibers,IHC showed the increased expression of endoplasmic reticulum stress related proteins GRP78 and calnexin,and apoptosis proteins of caspase-12 and Bax.ConclusionsThere is accumulation of abnormal proteins in muscle fibers in Chinese patients with Nonaka myopahty.These proteins may stimulate endoplasmic reticulum stress and apoptosis,which may be a mechanism responsible for muscle damage.
4.Risk factors for in-hospital ischemic stroke in the Department of Cardiology: a retrospective case-control study
Zubing XU ; Xiaobing LI ; Daojun HONG ; Yuchen WU
International Journal of Cerebrovascular Diseases 2013;21(9):673-677
Objective To investigate the clinical features,etiology and risk factors of the inpatients with ischemic stroke in the Department of Cardiology.Methods The medical records of the inpatients with ischemic stroke and the inpatients in a control group were collected retrospectively.The demographics,vascular risk factors,clinical features,and other related factors were compared in both groups.Multivariate logistic regression analysis was used to analyze the independent risk factors for in-hospital ischemic stroke in the Department of Cardiology.Results A total of 2 789 inpatients in departments of cardiology were enrolled,and 26 of them (0.93%) had in-hospital stroke.One hundred thirty inpatients from 2 763 patients without in-hospital stroke were used randomly as control cases.The proportions of the inpatients of hypertension (73.08% vs.50.77% ; x2=4.348,P=0.037),atrial fibrillation (50.00% vs.15.38%; x2=15.56,P=0.000),infection (30.77% vs.7.69% ; x2 =11.304,P =0.003),smoking (46.15% vs.21.54% ; x2 =6.886,P =0.009),alcohol (26.92% vs.11.54% ;x2 = 4.233,P =0.040),previous stroke history (19.23% vs.4.61% ;x2 =7.062,P =0.008),and taking anti-hypertensive drugs (42.31% vs.21.54% ;x2 =4.985,P =0.026),as well as systolic blood pressure (143.43 ± 18.59 mm Hgvs.129.52 ± 23.52 mm Hg; t =3.209,P=0.003; 1 mmHg =0.133 kPa),diastolic blood pressure (88.77± 11.35 mm Hg vs.77.55± 14.60 mmHg; t=2.421,P =0.020),and homocysteine levels (19.27 ± 11.08 μnol/L vs.15.30 ±5.25 μmol/L; t =2.814,P =0.006) in the stroke group were significantly higher than those in the control group in the Department of Cardiology.Multivariate logistic regression analysis showed that atrial fibrillation (odds ratio [OR] 3.310,95% confidence interval [CI] 1.207-9.076; P =0.020),infection (OR 3.270,95% CI 1.024-10.438; P =0.045),systolic blood pressure (OR 1.023,95% Cl 1.002-1.045; P =0.031),and homocysteine level (OR 1.089,95% CI 1.009-1.175; P =0.029) were the independent risk factors for in-hospital ischemic stroke in the Department of Cardiology.Conclusions Atrial fibrillation,infection,systolic blood pressure,and high homocysteine levels are the independent risk factor for in-hospital ischemic stroke in the Department of Cardiology.Active intervention and control these risk factors may have great significance for reducing its risk.
5.Filaminopathy caused by a novel deletion-insertion mutation in filamin C gene
Daojun HONG ; Xinghua LUAN ; Riliang ZHENG ; Wei ZHANG ; Yun YUAN
Chinese Journal of Neurology 2009;42(11):758-761
Objective To report filaminopathy with novel insertion mutation in a Chinese family.Methods Total 19 patients from successive 5 generations involved in an autosomal dominant family. The detailed clinical manifestations had been described (Chinese Journal of Neurology, 2008, 41:751-755).The filamin C gene sequencing was performed in 3 patients, 5 family members without symptoms and 50 normal persons. The amplified fragments of the exon 18 in filamin C gene were cloned into pBluesripts vectors, then sequenced and identified with capillary electrophoresis. Results 18-nucleotide deletion and 6-nucleotide insertion were identified in the exon 18 of filamin C gene. The mutation caused the disturbance of the seventh immunoglobulin-like domain in filamin C, leading to the instability of dimmers of filamin C.Another 2 patients in the family had same mutation while 5 family members without symptoms and 50 normal controls were normal. Conclusion The novel nucleotide deletion-insertion in exon 18 of filamin C gene causes filaminopathy. This disease can appear in non-Nordic race.
6.Clinical and pathological features of Danon disease associated with a novel lysosome-associated membrane protein-2B mutation
Daojun HONG ; Zhihong SHI ; Wei ZHANG ; Zhaoxia WANG ; Yun YUAN
Chinese Journal of Neurology 2010;43(10):707-711
Objectives To report the clinical and myopathological features in a case with Danon disease caused by a novel mutation in the lysosome-associated membrane protein-2 ( LAMP2 ) B gene.Methods A 16-year-old boy presenting progressive muscle weakness and atrophy, accompanied with spinal ankylosis was clinically evaluated including electrocardiogram, echocardiogram and electromyogram.Muscle biopsy was carried out in the patient.The histological staining, ultrastructural examination, and immunohistochemical staining with antibodies against dystrophin, merosin and C5b9 were performed in frozen sections.LAMP2B sequence was analyzed in the patient and his parents.Results Electrocardiogram in the patient showed Ⅰ atrioventricular block; echocardiogram revealed focal hypertrophy in mitral valve with mild cardiac diastolic dysfunction; electromyogram indicated myogenic and neurogenic patterns.Muscle pathology study revealed numerous vacuoles located at the fibers.Dystrophin, merosin and C5b9 was immuno-positive around the vacuoles.Electron microscopy revealed vacuoles surrounded by sarcolemma and abnormal lysosome aggregating at the fibers.A novel nonsense mutation ( K402X ) in the LAMP2B gene has been identified in the patient but not in his mother and 50 normal controls.Conclusions Danon disease caused by K402X mutation in C-terminus of LAMP2B presented benign course of the disease characterized by prominent vacuolar skeletal myopathy, mild cardiac abnormalities and peripheral neuropathy.
7.Clinical and pathological features in Charcot-Marie-Tooth disease type 2A2: a family report
Xiaohui QIAO ; Yuexing LI ; Daojun HONG ; Yun YUAN
Chinese Journal of Neurology 2010;43(5):341-344
Objective To report clinical and pathological features in a Chinese family with CharcotMarie-Tooth disease type 2A2 (CMT2A2). Methods There were 5 patients (2 male and 3 female) in a family with an autosomal dominant inheritance pattern. The index case was a 36 years old woman. She developed progressive distal limb weakness at the age of 6, with pescavus at the age of 8. Other 4 family members presented with similar symptoms between the age of 3-7. Physical examination showed distal limb weakness and wasting, loss of sensory and contracture in all of them. Nerve conduction velocity revealed non-potential in several motor and sensory nerves in the proband and her son. Sural nerve biopsy was performed on the proband. The sequence of MFN2 gene was analyzed in DNA from 5 patients and 3 asymptomatic members. Results Sural nerve biopsy revealed severe loss of myelinated fibers with few regenerating clusters. Electron microscopy revealed aggregation of mitochondrian in the axons. A R94W mutation in MFN2 gene has been identified in 5 patients, but not in unaffected members. Conclusions We confirmed Chinese CMT2A2. Absent of regenerating cluster in the nerve indicated that MFN2 mutation predominantly resulted in lesions in the neurons.
8.Clinical and magnetic resonance imaging studies of Anderson-Fabry disease: 2 cases report
Xiaoxuan LI ; Lu WANG ; Yun ZHANG ; Wei ZHANG ; Daojun HONG ; Zhaoxia WANG ; Huizhen GAO ; Yun YUAN
Chinese Journal of Neurology 2011;44(8):550-553
Objective To report 2 cases of Fabry disease with early-onset ischemic stroke and investigate the clinical and image features. Methods The 2 patients developed dizziness, diplopia and progressive memory decline at 32 and 25 years of age respectively. The α-galactosidase A (GLA)activity was 4. 3 U in case 1 and 1. 0 U in case 2 ( normal range 100-500 U). Skin biopsy showed numerous membrane bounded osmiophilic laminar material in vascular smooth muscle cells and endothelial cells. GLA gene analysis revealed GLA exon 7 1033-1034 TC del in case 1 and GLA exon 3 466G > A in case 2. The 2 patients were evaluated by Mainz severity score index (MSSI) and cranial MRI. Results The general MSSI was 32 in case 1 and 16 in case 2, with the highest score of neurological score ( 11 and 14). Both cases showed multifocal infarcts in bilateral cerebellum, occipital lobe, basal ganglia, which were hypointensity on T1 WI and hyperintensity on T2WI. There were hyperintensity changes in the pulvinar and basal ganglia on T1 WI in case 2. Conclusions Cerebral ischemic stroke could appear as initial symptoms in Fabry disease,which predominantly involved the posterior circulation. There might be no dilation of basal-vertebral artery.
9.Clinical features of thyrotoxic periodic paralysis caused by inwardly rectifying potassium channel 18 gene mutations
Daojun HONG ; Laimin LUO ; Meihong ZHOU ; Haihua HUANG ; Xiangbin WU ; Hui WAN ; Renxu XU
Chinese Journal of Neurology 2012;45(9):650-653
Objective To report the clinical features and inwardly rectifying potassium channel 18 (KCNJ18) gene mutation in a group of patients with thyrotoxic periodic paralysis (TTP).Methods Fiftyseven TTP cases (55 male and 2 female) were collected in our clinic from July 2002 to October 2011.The KCNJ18 gene was directly sequenced in 57 TTP patients and 50 health Chinese controls through the nested PCR.According to the results of gene screening,the clinical features of KCNJ18 patients and non-KCNJ18 patients were retrospectively summarized and analyzed.Results In 4 male patients with TPP,we found 3 novel heterogeneous mutations (p.Q126X,p.K360T,p.E388K) and 1 reported mutation (p.A200P) in the KCNJ18 gene.The age of onset was 19-25 years old,and the duration ranged from 2 to 8 hours.The 4 patients all presented severe muscle weakness.The attacks of muscle weakness preceded overt symptoms of hyperthyroidism in the 4 patients. Three patients showed recurrent weakness during the 13-28 months follow-up,while the episodic weakness never appeared when patients got euthyroid. Conclusions The mutations in the KCNJ18 gene are responsible for a part of Chinese patients with TPP.The patients with KCNJ18 mutations have a shorter disease course,severer manifestation,and higher prevalence of recurrence as compared with those TPP patients without KCNJ18 mutations.
10.Mutant connexin 32 abnormally distributed in the vascular endothelial cells of X-linked Charcot-Marie-Tooth disease type 1 patients
Xinghua LUAN ; Daojun HONG ; Xiaohui QIAO ; He Lü ; Zhaoxia WANG ; Yun YUAN
Chinese Journal of Neurology 2011;44(10):689-693
ObjectiveTo investigate expression distribution of mutant connexin 32 (Cx32) protein in human endothelial cells in patients with X-linked Charcot-Marie-Tooth disease type 1 ( CMTX1 ) .MethodsNerve biopsies were performed in 3 patients with CMTX1 and in 3 non-CMTX1 controls. Cx32 mutations of c. 379A > T( I127F), c. 533A > G(D178G) and c. 590C > T(A197V) were identified in these 3 patients respectively.Immunofluorescent (IMF) staining of nerve blood vessel was processed with antibodies against Cx32, Yon Willebrand factor and Cx40. The mutant Cx32 was constructed in pEGFP-N plasmid (pEGFP-N1-Cx32) and was transfected in HeLa cells. Cx32 and GRP78, a marker of endoplasmic reticulum ( ER), were stained by IMF in HeLa cells to investigate expression of mutant Cx32. ResultsIn 3 control cases, Cx32 was visualized by IMF staining as dots along gap junction of vascular endothelial cells,and it was coexisted with Cx40.However, immunoreactivity of Cx32 in 3 patients was predominantly decreased and was not located in endothelial gap junction. The transfection of 3 Cx32 mutants into HeLa cells demonstrated thepathogenic changes.The cells withthemutationc. 379A >T found Cx32 accumulations in the cytoplasm; the cells with mutation c. 533A >G showed few staining positive dots surrounding the nuclear and the cells with c. 590C > T showed dot-like expression of Cx32 both in the cytoplasmicand cell membrane. The mutant Cx32 was not overlapped with expression of the marker of ER.ConclusionsMutant Cx32 might cause dysfunction of endothelial gap-junctions due to the abnormal expression of Cx32 in level and location in the vascular endothelial cells of CMTX1 patients.