Construction, characterization and stability analysis of infectious clone of live attenuated dengue virus type 4 Ban18HK20 strain / 中华微生物学和免疫学杂志

Objective@#To construct a stable infectious clone of live attenuated dengue virus (DENV) type 4 Ban18HK20 strain for better understanding the virulence determinants of DENV and improving the development of chimeric vaccines.@*Methods@#Specific primers were constructed according to the genome of Ban18HK20 strain and used to subclone six cDNA fragments, which were linked into a high-copy plasmid pSPTM to obtain a stable full-length cDNA clone of DENV. RNA was transcribed from the full-length cDNA in vitro and electrotransfected into Vero cells to recover the virus. Biological characteristics of the recovered virus were identified using plaque assay, indirect immunofluorescence assay, growth kinetics test and pathogenicity study in mouse brain. Genetic stability of the virus passaged 15 generations was studied using RT-PCR amplification.@*Results@#Restriction enzyme digestion and sequencing analysis indicated that the infectious clone was constructed successfully. The recovered virus was consistent with the parental virus in terms of plaque morphology, DENV E protein expression, growth characteristics and pathogenicity in mouse brain. Sequencing analysis showed that the recovered virus had the same genome sequence as the parental virus with good hereditary stability.@*Conclusions@#A stable infection clone of Ban18HK20 was constructed and a reverse genetics technology platform for DENV research was established.

Present situation and progress in yellow fever attenuated live vaccine / 中华微生物学和免疫学杂志

The yellow fever (YF) attenuated live vaccine 17D is one of the oldest attenuated live vaccines and historically well known for its good immunogenicity and safety. Because of the high safety of YF attenuated live vaccine 17D, its genome is used as the backbone of recombinant vaccines that deliver flavivir-uses or non-associated antigens. With the prevalence of YF, the demand for YF attenuated live vaccines is increasing. At present, there is insufficient supply of YF attenuated live vaccines in the world. Much atten-tion has been paid to YF attenuated live vaccines. In this paper, the quality, use and prospect of YF attenu-ated live vaccine are reviewed.

Clinical features of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes：an analysis of 190 cases / 中华神经科杂志

Objective To summarize the clinical features of Chinese patients with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes ( MELAS).Methods A total of 190 patients with MELAS who presented to Peking University First Hospital between 1997 and 2015 were recruited.Among 190 patients, 175 were identified carrying mitochondrial DNA mutations, and the remaining 15 patients were diagnosed by muscle biopsy.The clinical features, including predisposing factors of stroke-like episodes, the onset symptoms and frequencies of various manifestations were analyzed and reported.Results In our cohort of MELAS patients, the male-to-female ratio was 1.44∶1.The median age of onset was 14 years ( from 7 months to 45 years).The peak onset ages were 8-12 years.The median onset age of the first stroke-like episode was 16 years ( from 1 to 53 years ).There were 66 ( 46.15%) patients who had predisposing factors before the onset, and fatigue and upper respiratory tract infection were the most common predisposing factors of stroke-like episodes in these patients ( 37.88%, 25/66 and 34.85%, 23/66, respectively).Other predisposing factors included emotional agitation, drinking alcohol, trauma, withdrawal of antiepileptic drugs, being frightened, satiation and hunger.Stroke-like episodes appeared in 70.53%(134/190) patients as an onset symptom and developed in all patients with disease progression.The neurological manifestations included seizure ( 89.42%, 169/189 ) , mental retardation or dementia (82.87%, 150/181), headache (74.30%, 133/179), hemianopia or cortical blindness (67.72%, 107/158), exercise intolerance (50.87%, 88/173), hemiplegia or hemianesthesia (47.44%, 74/156), sensorineural deafness (46.20%, 85/184), aphasia (39.47%, 60/152), behaviour disorder (17.71%, 31/175) and ophthalmoplegia ( 9.60%, 17/177 ).The manifestations of extra-nervous systems included hirsutism (67.57%, 100/148), vomiting (65.58%, 101/154), fever (62.07%, 90/145), short stature (45.32%, 63/139), diarrhea or constipation (43.48%, 70/161), low body mass index (26.62%, 37/139), diabetes mellitus (20.79%, 37/178) and kidney disease (3.16%, 6/190).Conclusions The majority of the patients in this study have the disease onset during childhood.There are more male MELAS patients than females.Most common clinical manifestations are seizure, mental retardation or dementia, headache, cortical blindness, hirsutism, vomiting and fever in this patient group.

Dynamic evolution of brain magnetic resonance imaging findings in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes syndrome / 中华神经科杂志

Objective To analyze the dynamic evolution of brain MRI in patients with mitochondrial myopathy,encephalopathy,lactic acidosis,and stroke-like episodes (MELAS) syndrome.Methods A retrospective study was performed on 58 MELAS cases with pathologically and (or) molecularly confirmed diagnosis.MRI were repeated within 60 days after the onset of stroke-like episodes (SLE) and the evolution changes of cerebral lesions were accessed.Brain atrophy index (BAI) was calculated in the remission stage from 31 patients with MELAS,and the correlation between BAI,age and disease duration was analyzed.Results The proportion of lesions expansion,migration and shrink within 30 days after the onset of SLE was 64.1％ (25/39),10.2％ (4/39),17.9％ (7/39),respectively,and 13％ (3/23),21.7％ (5/23),56.5％ (13/23),between 30-60 days after the onset of SLE respectively.In the recovery stage of SLE,the BAI in 31 patients with MELAS was 15.2％ ±2.8％.The correlation coefficient between BAI and the age,total disease course and duration of encephalopathy was 0.329 (P =0.043),0.405 (P =0.012) and 0.649 (P =0.000).Conclusions Brain atrophy in the studied MELAS patients gradually develops and strokelike lesions shrink with progression of the disease.However,the migration of lesions is persistent.

Audiological evaluation in Chinese patients with mitochondrial encephalomyopathies / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hearing impairment has been reported to be common in patients with mitochondrial disorders, a group of diseases characterized by pleiomorphic clinical manifestations due to defects in oxidative phosphorylation of mitochondria. This study aimed to investigate the audiological characteristics in a large cohort of patients with mitochondrial disease.</p><p><b>METHODS</b>Comprehensive audiological evaluations, including pure tone audiometry, tympanometry, speech audiometry, otoacoustic emissions, electrocochleography and auditory brainstem evoked potentials, were performed in 73 Chinese patients with mitochondrial encephalomyopathy and with confirmed mitochondrial DNA (mtDNA) defects.</p><p><b>RESULTS</b>Among the patients, 71% had hearing impairment. However, the incidence rate and severity of hearing impairment were much less in the chronic progressive external ophthalmoplegia (CPEO) subtype than in the mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), myoclonic epilepsy with ragged red fibers (MERRF) and Kearns-Sayre syndrome (KSS) subtypes. While most of our patients had a predominantly cochlea origin for the hearing deficit, five patients had an auditory neuropathy spectrum disorder and three patients had impairment of both cochlea and auditory cortex.</p><p><b>CONCLUSIONS</b>Various portions of the auditory system could be involved in patients with mitochondrial diseases, including cochlea, auditory nerve, auditory pathway and cortex. Hearing loss was more associated with multisystem involvement. Genotype, mutant load of mtDNA and other unknown factors could contribute to heterogeneity of hearing impairment in mitochondrial disease.</p>

Novel mutation of HTRA1 gene causes cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy: one case / 中华神经科杂志

ObjectiveTo report a novel HTRA1 gene mutation caused cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) with migraine,urinary retention and constipation.MethodsThe patient was a 34-year-old woman who suffered from myalgia with cramp for 16 years,lumbago for 5 years,migraine and mild alopecia for 3 years,right hemiparesis for 5 months,and urinary retention and constipation for 1 month.Vertebral MRI showed degeneration of vertebral bodies with disc herniations.Brain MRI revealed diffuse white matter lesions and lacunar infarcts.Sural nerve and skin biopsies were performed in the patient. HTRA1 gene analysis was performed in patient,her parents and 2 brothers,and Notch3 gene analysis in the patient.ResultsThe sural biopsy demonstrated discontinuous of elastica internal with thickness of intima of arterioles.The capillary basement membranes were thickness with mini granular changes.A homozygous T to A transition at position 524( c.524T ＞ A) was found in HTRA1 gene.The heterozygous c.524T ＞ A mutation appeared in the parents and 2 brothers,but not in the controls.Notch3 mutations were not found in the patient. Conclusion CARASIL caused by novel homozygous c.524T ＞ A mutation of HTRA1 gene can present with migraine,urinary retention and constipation.

Evaluation of vascular autoregulation in mitochondrial myopathy, encephalopathy, lactic acidosis,and stroke-like episodes patients / 中华神经科杂志

Objective To investigate the cerebral vascular autoregulation in patients with mitochondrial encephalomyopathy with lactic acidosis and strokc-like episodes (MELAS) during the remission of stroke-like episodes,including cerebrovascular CO2 reactivity and vascular endothelial function.Methods Twenty-nine MELAS patients confirmed by genetic analysis were recruited in this study. They underwent the examination at least 2 weeks after the onset of last stroke-like episode.Twenty-eight healthy people were collcctcd as healthy controls. Carotid ultrasound and brain magnetic resonance angiogram (MRA) were done to evaluate the cervical and intracranial appearance of large arteries. Evaluation of vascular autoregulation included: (1) the cerebrovascular CO2 reactivity with breath-holding test by transcranial Doppler and calculating breath holding index (BHI),and ( 2 ) flow-mediatcd dilation ( FMD )and nitroglycerin-mediated dilation with ultrasound assessment of humeral artery.Independent-samples t test was done between the results of two groups.Results Carotid ultrasound and cranial MRA revealed no abnormalities in both MELAS patients and healthy controls.The BHI of MELAS patients was significantly decreased than that of normal controls ( 1.36 ± 0.52 vs 1.81 ±0.26,t =- 3.693,P ＜ 0.01 ),and the FMD of MELAS patients was also significantly lower than that of normal controls (11.0％ ±4.8％ vs 15.8％ ±5.8％,t =-3.390,P ＜0.01).Conclusion The function of vascular autoregulation,including cerebrovascular CO2 reactivity and FMD,is impaired in MELAS patients.

Affected muscle fibers in Nonaka myopathy with endoplasmic reticulum stress / 中华神经科杂志

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.

Hot spot mutations in electron transfer flavoprotein dehydrogenase gene of riboflavin responsive lipid storage myopathy in 20 Chinese families / 中华神经科杂志

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.

Phenotype in 6 patients with mitochondrial DNA G13513A mutation / 中华神经科杂志

Objective To report 6 Chinese patients with mitochondrial encephalomyopathy caused by mitochondrial DNA(mtDNA)G13513A mutation and discuss the mitochondrial phenotype associated with this mutation based on the data of our patient series as well as the reports by others.Methods Direct sequencing of polymerase chain reaction(PCR)products or PCR-RFLP analysis Was performed to screen mtDNA G13513A mutation in 35 cases with mitoehondrial encephalomyopathy.who carried no mtDNA common mutations(1arge 8eale deletion,A3243G,T3271 C,A8344G,or T8993G/C).The clinical features,MRI changes were retrospectively collected and analyzed.Published studies of all patients with mtDNA G13513A mutation were also reviewed.Results Six patients were identified carrying mtDNA G13513A mutation.All patients presented stroke-like episodes with hemianopsia.hemiparesis or hemiparesthesia.Three adult patients presented clinical and radiological features of adult-onset mitochondrial myopathy,encephalopathy,lactic acidosis,and stroke-like episodes(MELAS),including stroke-like episodes,epilepsy,headache,short stature,sensorineural deafness,multifocal lesions on parietal,occipital and temporal lobes on cranial MRI scans.Three iuvenile.onset patients presented the clinical and brain MRI features of MELAS-Leigh syndrome(LS)overlap syndrome.In addition to the stroke-like episodes,they also showed brain stem lesions with dysarthria,ataxia,and ophthalmopJegia. Brain MRI revealed asymmetrical lesions in the cortex of the oecipital and temporal lobes,as well as symmetrical lesions in the bilateral basal ganglia and brainstem.Muslce biopsy showed ragged redfibem in 5 patients.The infant-onset LS or Leigh-like syndrome with mtDNA G135 13A was described in the English literature.Conclusions mtDNA G13513A mutation is a common pathogenic mutmion for mitochondrial encephalomyopathy,which can result in Leigh syndrome,MELAS-LS overlap syndrome and adult MELAS.The onset of various phenotypes is relatively age-dependent.

The inflammatory myopathy with abundant macrophages presenting with abundant foam cells: one case report / 中华神经科杂志

Objective To report the inflammatory myopathy with abundant macrophages presenting with abundant foam cells in a Chinese patient.Methods A 44 year-old man with rheumatoid arthritis manifested as progressive proximal muscle weakness in the upper limbs for 13 months and in the lower limbs for 11 months.Laboratory tests showed that serum creatine kinase level was increased,whereas neither the myositis antibody nor paraneoplasma antibodies were detectable,including anti-Jo-1 antibody.Electromyogram showed a classic myogenic pattern with irritable sarcomembrane excitement.Muscle biopsies were carried out in the left and right biceps brechii in 2 months and 13 months of the disease course respectively.The muscle sections were processed with standard histological,enzyme histochemistrical and immunohistochemical workup.Results The first muscle biopsy revealed CD8 positive T lymphocytes infiltrating into major histocompatibility complex (MHC)-Ⅰ positive fibers and distributing around endomysium,accompanied with scattered necrosis and regeneration.The second muscle biopsy showed perifascicular atrophy,fragmented perimysial connective tissue,and a large amount of CD68 positive foam cells and Touton cells accumulating within perimysial connective tissues and endomysium.Some CD20 positive B lymphocytes and plasmacytes were found around perivascular space,but CD8 positive T lymphocytes were only accumulated in the endomysium.MHC- Ⅰ was darkly expressed in the sarcolemma.Conclusions Inflammatory myopathy with abundant macrophages can present with foam cells infiltrating in perimysial and endomysium.The disease can be associated with rheumatoid arthritis and refractory to corticosteroid therapy.

Comparison of the clinical and magnetic resonance imaging characteristics of cerebral autosomal dominant arteriopathy with subcortical infarct and leucoencephalopathy in mainland China and other countries / 中华神经科杂志

Objectives To analyse the clinical and MRI features of cerebral autosomal dominant arteriopathy with subcortical infarct and leucoencephalopathy (CADASIL) in mainland China and compare these features with those reported in other countries.Methods All 26 CADASIL families were collected in First Hospital of Peking University from January 2003 to October 2009, and the diagnosis was confirmed by ultrastructural examination or Notch3 gene analysis.The age of onset, initial symptoms, main symptoms in 102 patients were described and the features with those reported in Germany, Japan, Arab and France were compared using x2 test.The cranial MRI changes in 35 patients were analysed and compared with the British and French patients.Results 102 patients had their initial symptoms between 22-80 years with the mean age of onset at (43.9 ± 11.0) years.There was no significant difference in the frequency of ischemic stroke or TIA (79.41% ) between our patients and the patients in other countries.Dementia rate (50.00% ) was significantly greater than that of Arab (21.05% ,x2 =5.513, P =0.020) and French patients(31.11%,x2 =4.517, P =0.034).The frequency of mood disturbances ( 14.71% ) was significantly lower than that of German patients (30.39% ,x2 =7.185, P =0.007).The frequency of migraine ( 13.73% ) was similar to that of France but lower than that of Japan (40%, x2 = 12.658, P = 0.000), Germany (38.24%, x2 =15.932, P=0.000) and Arab (42.11% ,x2 =6.869, P=0.009).Cranial MRIs were abnormal in all 35patients, but no lesion was seen in the medulla oblongata.Lacunar infarcts in the basal ganglia (82.86% )were significantly more frequent than that of French patients (60% , x2 = 5.663, P = 0.017).The frequency of leukoaraiosis in the cerebrum was similar to that of French patients.Anterior temporal involvement (68.57%) was significantly lower than of British patients ( 95%, x2 = 5.211, P = 0.022 ).Conclusion The clinical symptoms and MRI changes of CADASIL in different countries were not identical.Abnormal anterior temporal pole signal on MRI is not a sensitive marker for diagnosis of CADASIL in Chinese patients.

Effects of the main extracts of Astragalus membranaceus on inducing the erythroid differentiation of K562 cells / 解放军医学杂志

Objective To investigate the effects of different astragalosides(AST) and hydro-soluble astragali polysaccharide(APS) of Astragalus membranaceus on inducing erythroid differentiation of human leukaemic K562 cells.Methods APS and AST were extracted by alcohol or water from Astragalus membranaceus.K562 cells were treated with APS,AST and sodium butyrate(BA) respectively.The proportion of benzidine-positive cells was examined after 1-4 days culture.MTT assay was performed for evaluating the proliferation effects of APS,AST and BA on K562 cells.Results The percentages of benzidine-positive cells induced by APS,AST and BA were 13.2%,2.9% and 17.5%,respectively.The kinetic characteristics of K562 cells induced by different levels of APS(1,2,4,8mg/ml) indicated that 4 mg/ml APS was sufficient to induce K562 cells to turn to be benzidine-positive.The results suggested that APS,other than AST,could induce the K562 cells towards erythroid differentiation.Compared with BA,the percentage of benzidine-positive cells induced by APS was lower at 24h,48h and 72h(F=237.44,P=0.00),while the total number of benzidine-positive cells was higher at 96h(F=322.25,P=0.00).The results of MTT assay for Absorbance(A) showed that APS and AST had no inhibitory effects on growth of K562 cells(P=0.28,P=0.11),while BA showed an obvious inhibitory effect on K562 cells(P=0.00).Conclusion Astragalus membranaceus has pharmacological effects to induce the K562 cells towards erythroid differentiation,and its valuable constituents are contained in hydro-soluble astragali polysaccharide(APS).The induction of differentiation is most evident with a dosage of 4 mg/ml APS.The cell growth curve reveals that APS has no inhibitory effect on K562 cells.