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Ji-feng Guo

Publications and source records attributed to Ji-feng Guo.

10 recordsLinked to original sources
PubMed2006

[Exon rearrangement analysis of parkin gene in patients with isolated early-onset parkinsonism using semi-quantitative PCR].

OBJECTIVE: To investigate the value of fluorescence semi-quantitative PCR in analysis of the exon rearrangement of parkin gene in Chinese patients with isolated early-onset parkinsonism (EOP). METHODS: fluorescence semi-quantitative PCR was used to analyze the exon rearrangements of parkin gene in 61 isolated patients with EOP. RESULTS: Exon deletions in parkin gene were found in 4 of the 61 isolated patients with EOP. One of them failed to show the PCR product of exon 4 and had homozygous deletions of exon 4. The normalized ratios (NRs) of exon 2, exon 3, and exon 4 of the other 3 patients were 0.47, 0.52, and 0.49 respectively, showing that they had heterozygous deletions of exon 2, 3, and 4 respectively. No exon multiplication was found in this study. CONCLUSION: Exon rearrangement of parkin gene exists in Chinese patients with isolated EOP.

Adolescent↗
PubMed2006

[The wild-type alpha-synuclein over-expression to induce the protein aberrant aggregation of alpha-synuclein in HEK293 cells in vitro].

OBJECTIVE: To investigate over-expression of wild-type alpha-synuclein inducing the aberrant aggregation of alpha-synuclein in HEK293 cell in vitro. METHODS: The cDNA encoding the human alpha-synuclein without the stop code was cloned into PGEM T-easy vector. Using enzyme map and DNA sequencing analyzed and determined the recombinant plasmid, and then sub-clone the alpha-synuclein cDNA fragment into pEGFP-N1 vector. The recombinant plasmids alpha-synuclein-pEGFP were transfected into HEK293 cells by lipofectamin 2000. The aberrant aggregation of alpha-synuclein was measured by EGFP fluorescence, anti-alpha-synuclein immunocytochemistry. The inclusions in the cultured cells were identified with HE staining. RESULTS: The restriction enzyme map suggested that eukaryotic expression vector for human wild-type alpha-synuclein gene was constructed successfully. By EGFP fluorescence, anti-alpha-synuclein immunocytochemistry, it could be observed that the alpha-synuclein protein could aggregate in cytoplasm and the Lewy body-like inclusions found in cytoplasm of cultured cells. CONCLUSION: The over-expression of wild-type alpha-synuclein can induce protein aberrant aggregation and Lewy body-like inclusions formation in cytoplasm of HEK293 cell in vitro.

Cells, Cultured↗
PubMed2006

[Genotype and phenotype analyses of three families with autosomal recessive juvenile parkinsonism].

OBJECTIVE: To investigate the gene mutations and the clinical features of Chinese patients with autosomal recessive juvenile parkinsonism(AR-JP). METHODS: the polymerase chain reaction (PCR), DNA sequence analysis, and restriction enzyme digestion analysis were applied to check parkin gene mutations of 15 index patients from 15 families with AR-JP. RESULTS: Three families were detected to have parkin mutations. Two of them had heterozygous deletion mutations (202-203 del AG in exon 2, 1069-1074 del GTGTCC in exon 9) and another of them carried a heterozygous missense mutation [1422(T-->C) in exon 12]. Two of the mutations [1069-1074delGTGTCC and 1422(T-->C)] were not reported previously. There were six patients in the three families. Mean age at onset was 25.2+/-5.7 years, ranging from 18 to 31 years. The symptoms were under slow progression, diurnal fluctuation with sleep benefit, and hyperreflexia were relatively prominent. Response to levodopa was satisfactory. CONCLUSION: There are parkin mutations happened in Chinese patients with AR-JP. Patients with parkin mutations have distinct clinical features besides the common clinical features of Parkinson's disease.

Adult↗
PubMed2006

[Clinical and mutational analysis of KCNQ3 gene in a Chinese family with benign familial neonatal convulsions].

OBJECTIVE: To study the clinical and genetic characteristics of a Chinese family with benign familial convulsions (BFNC). METHODS: The clinical data of this family was analyzed. The blood samples were collected from 13 members of this family. By four microsatellite markers which are located in the gene loci of both K+ channel KCNQ2 and KCNQ3, the linkage analysis was performed in the family. With DNA direct sequencing and restriction endonuclease cutting analysis, the mutation analysis of KCNQ3 gene was made for the proband, other 12 family members and 76 unrelated normal individuals. RESULTS: There were 7 patients with BFNC observed in the three generation of family. The BFNC seizures of all patients disappeared during one month and no recurrence of seizures was found. The linkage analysis suggested the disease gene linked to KCNQ3 gene locus in the family. The mutation 988(C to T) of KCNQ3 gene was found in the proband by DNA-direct sequencing. Cosegregation of this mutation with BFNC was confirmed by restriction endonuclease cutting analysis. CONCLUSION: Chinese patients with BFNC can be caused by KCNQ3 gene mutation.

Base Sequence↗
PubMed2006

[Fast image denoising based on mathematical morphology].

There is a contradiction between image denoising and protection of the useful information in the image. To deal with this contradiction, we use the approach of mathematical morphology. In this paper, we expound the method and effectivity of mathmatical morphology in image processing. Based on it, an improved and fast image denoising algorithm is proposed and some experiments have been made to show that this algorithm is simple, effective and feasible.

Algorithms↗
PubMed2005

[Mutation analysis of PINK1 gene in Chinese patients with autosomal recessive early-onset parkinsonism type 6].

OBJECTIVE: To detect PINK1 gene mutations and study the clinical features in Chinese patients with autosomal recessive early-onset parkinsonism (AREP) type 6. METHODS: PINK1 gene mutations were detected using polymerase chain reaction (PCR), DNA sequence analysis, and restriction enzyme digestion analysis in 11 index probands of 11 AREP families. RESULTS: Two novel point mutations in PINK1 gene, C938T in exon four, leading to substitution of a threonine for methionine codon at amino acid 313 (T313M) and C1474T in exon seven introducing a stop codon at amino acid 492 (R492Stop), were found in two families. In another family, a synonymous mutation (Y454Y) was detected. The clinical features in patients with PINK1 mutations included early onset, slow disease progression, hyperreflexia, diurnal fluctuations with sleep benefit, and good response to levodopa. However, dyskinesias related to levodopa treatment were absent. CONCLUSION: PINK1 gene mutations are a common cause of AREP. PARK6 pedigrees have been firstly identified in Chinese Mainland. Clinical heterogeneity exists in PARK6.

Adolescent↗
PubMed2005

Novel compound heterozygous mutations in the PANK2 gene in a Chinese patient with atypical pantothenate kinase-associated neurodegeneration.

We investigated the presence of mutations in the pantothenate kinase (PANK2) gene in a 27-year-old male Chinese patient with atypical pantothenate kinase-associated neurodegeneration (PKAN), formerly Hallervorden-Spatz syndrome. Automated DNA sequence analyses revealed compound heterozygous mutations in the exon 3 and 5. This patient had a 10-year history of PKAN characterized by a slight tremor of the right hand when writing at onset and a slow progressive rigidity of the neck and the right arm and resting tremor in upper extremities. Dysarthria, dysphagia, and dystonic-athetoid movements of the face and right fingers were marked. Magnetic resonance showed the typical "eye-of-the-tiger" sign.

Adult↗
PubMed2005

[The clinical and genetic characteristics of autosomal recessive juvenile Parkinsonism in a Chinese family].

OBJECTIVE: To understand clinic and genetic characteristics of Chinese AR-JP. METHODS: The clinical dates of 1 Chinese AR-JP family was collected and analysed. Genomic DNA was extracted by standard techniques from venous blood leukocytes of members in three women of the family, polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) analysis and DNA sequencing were used to detect mutation of parkin gene. RESULTS: Onset age of 2 Chinese AR-JP patients is young, periods of disease is long, clinical manifestation include: resting tremor, rigidity, bradykinesias, disability, a good response to levodopa, but early levodopa induced symptom fluctuation; but no hyperactive tendon reflexes, sleep benefit, and foot dystonia. Parkin mutation analysis in 2 patients of the family discovered abnormal SSCP electrophoresis band, by DNA examination, conformed 2 base deletion mutation (exon 2 202-203delAG). CONCLUSIONS: Clinical features of Chinese AR-JP patients are different with Japanese AR-JP, similar with late-onset Parkinson disease; our study detected a parkin mutation (exon 2 202-203delAG), conform mutation of parkin gene is a cause of AR-JP in Chinese.

Adult↗
PubMed2005

[Mutation analysis of DJ1 gene in patients with autosomal recessive early-onset Parkinsonism].

OBJECTIVE: To investigate the mutation characteristics of DJ1 gene in Chinese patients with autosomal recessive early-onset Parkinsonism (AR-EP). METHODS: Mutations of DJ1 gene were screened by polymerase chain reaction combined with DNA direct sequencing in index patients with AR-EP from 11 unrelated families. RESULTS: No pathogenetic mutations in the DJ1 gene were detected in this group. Six intronic DJ1 polymorphisms (IVS1-15T-->C, IVS4+30T-->G, IVS4+45G-->A, IVS4+46G-->A, IVS5+31G-->A, g.168-185del) were found. Three of them (IVS1-15T-->C, IVS4+45G-->A, IVS4+46G-->A) were not reported previously. CONCLUSION: DJ1 mutations were rare in Chinese patients with autosomal recessive early-onset Parkinsonism.

Adolescent↗