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Yan Shen

Publications and source records attributed to Yan Shen.

At least 145 records · Page 8Linked to original sources
PubMed2003

Association between genetic variation of CACNA1H and childhood absence epilepsy.

Direct sequencing of exons 3 to 35 and the exon-intron boundaries of the CACNA1H gene was conducted in 118 childhood absence epilepsy patients of Han ethnicity recruited from North China. Sixty-eight variations have been detected in the CACNA1H gene, and, among the variations identified, 12 were missense mutations and only found in 14 of the 118 patients in a heterozygous state, but not in any of 230 unrelated controls. The identified missense mutations occurred in the highly conserved residues of the T-type calcium channel gene. Our results suggest that CACNA1H might be an important susceptibility gene involved in the pathogenesis of childhood absence epilepsy.

Age of Onset↗
PubMed2003

GenomeComp: a visualization tool for microbial genome comparison.

We have developed a software tool, GenomeComp, for summarizing, parsing and visualizing the genome sequences comparison results derived from voluminous BLAST textual output. With GenomeComp, the variation between genomes can be easily highlighted, such as repeat regions, insertions, deletions and rearrangements of genomic segments. This software provides a new visualizing tool for microbe comparative genomics.

Computational Biology↗
PubMed2003

Genome-based analysis of virulence genes in a non-biofilm-forming Staphylococcus epidermidis strain (ATCC 12228).

Staphylococcus epidermidis strains are diverse in their pathogenicity; some are invasive and cause serious nosocomial infections, whereas others are non-pathogenic commensal organisms. To analyse the implications of different virulence factors in Staphylococcus epidermidis infections, the complete genome of Staphylococcus epidermidis strain ATCC 12228, a non-biofilm forming, non-infection associated strain used for detection of residual antibiotics in food products, was sequenced. This strain showed low virulence by mouse and rat experimental infections. The genome consists of a single 2499 279 bp chromosome and six plasmids. The chromosomal G + C content is 32.1% and 2419 protein coding sequences (CDS) are predicted, among which 230 are putative novel genes. Compared to the virulence factors in Staphylococcus aureus, aside from delta-haemolysin and beta-haemolysin, other toxin genes were not found. In contrast, the majority of adhesin genes are intact in ATCC 12228. Most strikingly, the ica operon coding for the enzymes synthesizing interbacterial cellular polysaccharide is missing in ATCC 12228 and rearrangements of adjacent genes are shown. No mec genes, IS256, IS257, were found in ATCC 12228. It is suggested that the absence of the ica operon is a genetic marker in commensal Staphylococcus epidermidis strains which are less likely to become invasive.

Adhesins, Bacterial↗
PubMed2003

Association analysis of a polymorphism of interleukin 1 beta (IL-1 beta) gene with temporal lobe epilepsy in a Chinese population.

PURPOSE: Temporal lobe epilepsy with hippocampal sclerosis (TLE-HS+) is one of the most common medically intractable epilepsies. Although the pathogenesis of HS+ still remains highly controversial, genetics may play a role as a predisposing factor. Previous evidence in a Japanese population shows that the homozygotes for allele 2 at position -511 of the interleukin (IL)-1 beta gene promoter region (IL-1 beta-511*2/2) confers susceptibility to the development of HS. However, this result has not been confirmed in populations of European ancestry. Given that the discrepancy may be attributed to ethnic differences, our aim in this study was to test the validity of a previous report in another Asian population. METHODS: This study consisted of total 112 nonlesional TLE patients of Chinese ancestry, and 115 ethnically matched control subjects. A 304-base pair fragment in position of IL-1 beta-511 was amplified by polymerase chain reaction (PCR). The PCR products were digested with restriction enzyme AvaI, and run on a 12% polyacrylamide gel. We compared the frequency of this gene variation among 67 refractory TLE-HS+ patients, 45 patients without HS (TLE-HS-), and normal control subjects. RESULTS: The heterozygous type (-511*1/2) is the most common genotype in our patient groups and controls. Allele 1 (-511C) and allele 2 (-511T) showed equal frequency ( approximately 50%), which is similar to that (46%) in Japanese. Analysis of genotype and allele distribution showed no significant difference among the three groups (p > 0.05). CONCLUSIONS: In contrast with the lower frequency in the white population (35 and 34%) and higher rate in the population of African ancestry (60%), the allele -511T frequency in our present study is approximately 50%, indicating differences in the distribution of allele frequencies in IL-1 beta-511 among different ethnic groups. In this Chinese population, however, we still did not find a strong association between IL-1 beta-511 polymorphism and the development of HS.

Adult↗
PubMed2003

Linkage analysis of 2q14-q23 and 5q32 with blood pressure quantitative traits in Chinese sib pairs.

OBJECTIVES: Several genome-wide scans recently accomplished in the ethnic Chinese revealed a number of candidate loci possibly contributing to essential hypertension, and some appeared to be replicable in 2q14-q23 and 5q32. The current study aimed to examine the linkage of qualitative and blood pressure quantitative traits in essential hypertension with these genomic regions in a large sample of Chinese hypertensive families. METHODS: We performed a genetic analysis on 148 randomly ascertained families containing 328 affected sib pairs, grouped into two geographically distinct subsets. Five highly informative microsatellite markers (D2S151, D2S142, D5S2090, D5S413 and D5S2013) were genotyped, and linkage analyses were performed with different genetic models. RESULTS: We did not observe consistent evidence for excess allele sharing identity by descent in either of the qualitative or the quantitative test. However, higher LOD scores were found at D5S2013 in North Group subset with Haseman-Elston and maximum likelihood (ML) variance (no dominance variance, NDV) algorithms. With the ML (NDV) algorithm, the LOD was 1.410 for diastolic blood pressure at this locus, although this was not statistically significant. CONCLUSIONS: These findings provide no evidence to support a significant linkage of 2q14-q23 or 5q32 with essential hypertension or blood pressure quantitative traits in the ethnic Chinese, and indicate the aetiologic diversity and complexity of hypertension. Previous reports implied 2q14-q23 or beta 2- adrenergic receptor gene potentially linked to essential hypertension in the ethnic Chinese. To replicate these results and perform quantitative linkage analysis, we genotyped members of 148 hypertensive families with five highly informative microsatellite markers. We observed no evidence of excess allele sharing identity by descent in sib pairs, revealing a lack of linkage between 2q14-q23 or 5q32 (chromosome region harboring the gene encoding beta 2 adrenergic receptor) and hypertension in our study sample.

Adult↗
PubMed2003

Variation near the region of the lipoprotein lipase gene and hypertension or blood pressure levels in Chinese.

Essential hypertension (EH) is a common late-onset disease that exhibits complex genetic heterogeneity. Human lipoprotein lipase (LPL) is a rate-limiting enzyme that regulates the catabolism of triglycerides (TG) and chylomicrons (CM). Since dyslipidemia is a common finding in hypertensive patients, the LPL gene is a logical candidate gene that could contribute to the development of hypertension. Using linkage analysis in 148 Chinese hypertensive families, we identified a region of linkage with systolic blood pressure (SBP) and diastolic blood pressure (DBP) that consisted of a 10.6-cM interval defined by markers D8S1145, D8S261, and D8S282 on chromosome 8, which maps between 31 to 41.6 cM from the 8p-telomere contained LPL gene, with statistically significant p values for the marker D8S261 (p = 0.0021 for SBP, and p = 0.0395 for DBP). In the qualitative-trait linkage analysis, evidence for linkage between the marker D8S1145 and EH was found (p = 0.0286). The transmission/disequilibrium test (TDT/S-TDT) also supported a significant linkage-disequilibrium of the allele 3 of D8S261 with EH (chi2 = 8.643, p < 0.01). Furthermore, the marker neurofilament light polypeptide (NEFL) (11 cM centromeric to the LPL gene) appeared to be in linkage with SBP and DBP (p = 0.0329 for SBP; p = 0.0319 for DBP). Additionally, two flanking markers for LPL, D8S511 (9.5 cM telomeric to the LPL gene) and D8S560 (3.2 cM centromeric to the LPL gene), also showed significant linkage with EH (p = 0.0036 for D8S511; p = 0.0115 for D8S560). Previous knowledge about the physiological involvement of LPL in blood pressure regulation and the present findings of variation near the LPL gene support the proposition that a region near the LPL gene or the LPL gene itself might contribute to the individual blood pressure variation in Chinese.

Adult↗
PubMed2003

Synergistic effect of cell differential agent-II and arsenic trioxide on induction of cell cycle arrest and apoptosis in hepatoma cells.

AIM: To illustrate the possible role of cell differential agent-II (CDA-II) in the apoptosis of hepatoma cells induced by arsenic trioxide (As(2)O(3)). METHODS: Hepatoma cell lines BEL-7402 and HepG2 were treated with As(2)O(3) together with CDA-II. Cell surviving fraction was determined by MTT assay; morphological changes were observed by immunofluorescence staining of Hoechst 33,258; and cell cycle and the apoptosis index were determined by flow cytometry (FCM). RESULTS: Cytotoxicity of CDA-II was low. Nevertheless, CDA-II could strongly potentiate arsenic trioxide-induced apoptosis. At 1.0 g/L CDA-II, IC(50) of As(2)O(3) in hepatoma cell lines was reduced from 5.0 micromol/L to 1.0 micromol/L (P<0.01). The potentiation of apoptosis was dependent on the dosage of CDA-II. FCM indicated that in hepatoma, cell growth was inhibited by CDA-II at lower concentrations (<2.0 g/L) primarily by arresting at S and G(2) phase, and at higher concentrations (>2.0 g/L) apoptotic cell and cell cycle arresting at G(1) phase increased proportionally. The combination of two drugs led to much higher apoptotic rates, as compared with the either drug used alone. CONCLUSION: CDA-II can strongly potentiate As(2)O(3)-induced apoptosis in hepatoma cells, and two drugs can produce a significant synergic effect.

Apoptosis↗
PubMed2003

Protein kinase C/zeta (PRKCZ) gene is associated with type 2 diabetes in Han population of North China and analysis of its haplotypes.

AIM: To identify the susceptible gene (s) for type 2 diabetes in the previously mapped region, 1p36.33-p36.23, in Han population of North China using single nucleotide polymorphisms (SNPs) and to analyze the haplotypes of the gene (s) related to type 2 diabetes. METHODS: Twenty three SNPs located in 10 candidate genes in the mapped region were chosen from public SNP domains with bioinformatic methods, and the single base extension (SBE) method was used to genotype the loci for 192 sporadic type 2 diabetes patients and 172 normal individuals, all with Han ethical origin, to perform this case-control study. The haplotypes with significant difference in the gene (s) were further analyzed. RESULTS: Among the 23 SNPs, 8 were found to be common in Chinese Han population. Allele frequency of one SNP, rs436045 in the protein kinase C/zetagene (PRKCZ) was statistically different between the case and control groups(P<0.05). Furthermore, haplotypes at five SNP sites of PRKCZ gene were identified. CONCLUSION: PRKCZ gene may be associated with type 2 diabetes in Han population in North China. The haplotypes at five SNP sites in this gene may be responsible for this association.

Asian People↗
PubMed2003

[Ototoxic study spiral ganglion neurons in the pig guinea with ethylene oxide remained in absorbable gelatin sponge].

OBJECTIVE: To measure ethylene oxide remained in absorbable gelatin sponge, and to observe change of ultrastructure in spiral ganglion neurons after deposited in otic vesicle of pig guinea with ethylene oxide sterilized absorbable gelatin sponge. METHOD: To use comparative colour technique measuring ethylene oxide remained in absorbable gelatin sponge, by means of transmission electron microscope to observe change of ultrastructure in spiral ganglion neurons after 3 months deposited in otic vesicle of pig guinea with ethylene oxide sterilized absorbable gelatin sponge. RESULT: The mean value of ethylene oxide remained in absorbable gelatin sponge were 438.32 mg, while nation standard are less 10 mg, FDA standard(1978) less 25 mg. ultrastructural appearance showed condensed matric electron dense of spiral ganglion mitochondria and dark crista of mitochondria, vacuolated cytoplasm. Ultrastructural observation also demonstrated dissolution or necrosis of ganglion cells, satellite cells, and vacuolated myelin. These changes were near Donson reported(1997) intracochlear perfusion with aminoglycosides. CONCLUSION: The mean value of ethylene oxide remained in absorbable gelatin sponge were 40 times nation standard. Toxic changes of ethylene oxide remained in absorbable gelatin sponge in spiral ganglion neurons were similar to intracochlear perfusion with aminoglycosides.

Animals↗
PubMed2003

[Clinical analysis of different periods of liver transplantation at an organ transplantation centre].

OBJECTIVE: To summarize our clinical experience in liver transplantation while considering the background in this field in China. METHODS: Ninety-five patients who had received liver transplantation from April 1993 to March 2002 were analyzed retrospectively. Three periods were defined objectively as period I (1993 - 1997), II (1999) and III (2000 - 2002). Operative techniques, recipients, original diseases, complications and survival rates were compared among the three periods. RESULTS: Malignant liver lesions were the main cause for liver transplantation in period I and II. The ratio of number of malignant disease to total recipients decreased gradually from period I to III (100%, 53% and 35%, respectively). The 1-year survival rate in patients with benign liver disease was 85% and the total operative mortality was 5% in period III. The incidence of hepatitis B virus reactivation or reinfection was 24% twelve months after liver transplantation. Vascular complication decreased but biliary complications did not and remained a major long-standing problem. No veno-venous bypass technique was used in period III, and its advantages were obvious when comparing with those with veno-venous bypass in period I and II. CONCLUSIONS: Strict selection of recipients, fine operative technique, familiarity with various complications and correct therapeutic methods, prophylaxis of recurrence of hepatitis B and hepatocellular carcinoma are necessary to improve long-term results of liver transplantation in China.

Adult↗
PubMed2003

[Exogenous expression of SOCS box-deficient mutant ASB-8 suppresses the growth of lung adenocarcinoma SPC-A1 cells].

ASB-8 is a new member of the human ankyrin repeat and SOCS box containing protein family (ASB). This report deals with the expression of ASB-8 protein in lung carcinoma tissue, as well as its biological effect on the proliferation and growth of lung cancer cell line SPC-A1. ASB-8 was expressed in pT7-450 expression vector, and an anti-ASB-8 rabbit polyclonal antibody was prepared. The expression of ASB-8 protein in lung carcinoma tissue was detected using immunohistochemistry. The growth characteristics of the lung adenocarcinoma SPC-A1 cells expressing either exogenous ASB-8 or ASB-8 SB (SOCS box-deficient) was studied by both in vitro cell growth curve and in vivo nude mouse tumor formation assay. Immunohistochemical staining detected positive reaction of 96.8% (30/31) showing that ASB-8 was highly expressed in lung cancer tissues; however, the expression of ASB-8 was lower, or even no expression in noncancerous lung tissues. Significant growth inhibition was observed in SPC-A1 cell line expressing ASB-8 SB on day 4 and persisted to day 6, compared with mock transfected cells (P<0.01). No difference in the growth properties was observed between ASB-8 and mock transfected cells. In vivo study also showed that tumor formation of ASB-8 SB expressing cells was significantly inhibited as compared with that of the control group (P<0.01). Therefore, ASB-8 may play an important role in growth and proliferation of lung cancer, possibly as positive regulator.

Adenocarcinoma↗
PubMed2003

Glivec enhances the down-regulated cytotoxicity of adriamycin in acquired tamoxifen-resistant MCF-7 cell line.

OBJECTIVE: To study the alteration of bax, bcl-2, p170 expressing and the second effect on the adriamycin (ADR) induced cytotoxicity in acquired tamoxifen (TAM)-resistant MCF-7 cell line. METHODS: The bax, bcl-2, p170 protein expressions were detected by flow cytometry respectively, as well as the content of intracellular ADR. The in vitro adenosine triphosphate tumor chemosensitivity assay (ATP-TCA) was performed to evaluate the cytotoxicity of ADR, and also the effect of Glivec on the cytotoxicity of ADR. RESULTS: The percentages of bax, bcl-2 expressions in the acquired TAM resistant MCF-7 were down-regulated from 53.17+/-1.45% to 28.70+/-1.41% (P <0.01), 41.53+/-2.17% to 37.87+/-1.86% P >0.05 respectively, the p170 was up-regulated from 27.43+/-2.16% to 32.13+/-1.31% (P <0.05), after a 16-week-treatment with 1 x 10(-7) mol/L TAM. Accordingly, the chemosensitivity and the fluorescence intensity of intracellular ADR declined, both of them can be significantly reversed by 10 microg/ml Glivec. CONCLUSION: The acquired TAM resistant MCF-7 accompanied with a declined ADR cytotoxicity, down-regulation of bcl-2/bax-induced apoptosis and up-regulation of p170-induced drug efflux may had a synergic devotion. Glivec may enhance the cytotoxicity of ADR on the acquired TAM-resistant MCF-7 cell line.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed2003

[Early diagnosis of pancreatic cancer is essential to improving the effect of treatment].

OBJECTIVES: To explore the relation between tumor TNM of pancreatic cancer and treatment, and to summarize the experience in diagnosis and treatment of pancreatic cancer. METHODS: The data on 321 patients with pancreatic cancer treated at our hospital between January 1990 and December 2000 were reviewed retrospectively. Radical resection and survival for various TNM stages were analyzed. RESULTS: The rates of radical resection for stage I, stage II, stage III, stage IVA, and stage IVB were 100%, 100%, 82.6%, 12.3% and 2.1% respectively. The 1-, 3- and 5-year survivals of stage I, II were 73.3%, 40.0% and 30.0% respectively, and higher than those of other groups. CONCLUSIONS: The patients with pancreatic cancer diagnosed early can undergo radical resection. The elevation of early diagnosis rate is significant for the improvement of survival.

Adolescent↗
PubMed2003

[Analysis on the SARS-CoV genome of PUMC01 isolate].

OBJECTIVE: To perform variation and phylogenetics analysis on the SARS-CoV genome sequence (PUMC01) isolated in the Peking Union Medical College Hospital. METHODS: The cDNA library of SARS-CoV (PUMC01 isolate) was constructed by means of random-priming strategy. Random selected plasmid was sequenced and the genome sequence of SARS-CoV-PUMC01 was assembled by conventional methods (The Genebank Accession No. of SARS-CoV-PUMC01 is AY350750). The variation and phylogenetics analysis were performed by comparing the PUMC01 sequence with other SARS-CoV isolates. RESULTS: Ten variation sites were found by comparing PUMC01 isolate with Tor2 and Urbani isolates. In phylogenetic analysis of 18 SARS-CoV isolates, two classes were observed and there is different differential time between these two classes and the different isolates in each class. CONCLUSIONS: The evidence of phylogenetic analysis of different SARS-CoV isolates from different region is instructive for understanding the clinical relations between the different isolates and the transmission chain of SARS-CoV.

Amino Acid Sequence↗
PubMed2003

[cDNAs cloning of SARS-CoV PUMC2 viral genome].

OBJECTIVE: To get the cDNA clones which cover the whole genome of SARS-CoV PUMC2 strain. METHODS: Using the SARS-CoV PUMC2 strain genomic RNA as the template, the cDNA fragments were amplified by RT-PCR, the PCR products were further purified and ligated into the pGEM-T vector, and all the clones obtained were sequenced. RESULTS: The cDNA clones which cover the whole genome of SARS-CoV PUMC2 strain were obtained. CONCLUSIONS: These cDNAs can be provided for the function study of SARS-CoV proteins and the construction of full-length infectious cDNA clone of SARS-CoV.

Amino Acid Sequence↗
PubMed2003

[Cloning, expression and purification of SARS coronavirus PUMC2 strain nucleocapsid protein].

OBJECTIVE: To clone, express and purify nucleocapsid protein from SARS coronavirus PUMC2 strain. METHODS: According to the published SARS coronavirus genome sequences, the full length cDNA of N protein from SARS coronavirus PUMC2 strain was cloned by RT-PCR and the cDNA was cloned into the pET32a expression vector. The recombinant N protein was expressed in E. coli BL21 (DE3), and purified by Ni(2+)-NTA. RESULTS: Prokaryoticly expressed and purified N protein of SARS coronavirus PUMC2 strain was obtained. CONCLUSIONS: The SARS coronavirus recombinant N protein obtained by genetic engineering methods can be used for further functional study of SARS coronavirus N protein.

Amino Acid Sequence↗
PubMed2003

[Isolation and identification of SARS-coronavirus in nasal and throat swabs collected from clinically diagnosed SARS patients].

OBJECTIVE: To isolate and identify SARS-coronavirus in nasal and throat swabs collected from clinically diagnosed severe acute respiratory syndrome (SARS) patients. METHODS: Nasal and throat swab specimens were inoculated onto well of 24-well plate containing confluent monolayers of Vero and MRC-5 cells. Isolates were identified with serology, electron microscopy and genome sequence. RESULTS: One hundred and fifty-eight nasal and throat swabs specimens from 79 SARS patients in Peking Union Medical College Hospital between April and May, 2003 were cultured for SARS-coronavirus. Cytopathic effect (CPE) was found in three nasal swab specimens inoculated in Vero cells. Acute and convalescent phase serum specimens collected from SARS patients were found with seroconversions and/or a fourfold or greater rises in indirect fluorescence antibodies (IgG and IgM) titers when the 3 isolates (infected Vero cells) were used as antigen. Coronavirus was observed in the culture supernatant by negative-stain electron microscopy. Genome sequence confirmed the isolates were SARS-coronavirus. CONCLUSIONS: The 3 isolates from nasal and throat swabs samples collected from 79 clinically diagnosed SARS patients were SARS coronavirus.

Adolescent↗