Biomedical subjects

Yan Shen

Publications and source records attributed to Yan Shen.

At least 109 records · Page 6Linked to original sources

PubMed2004

Variants in TNFRSF5 locus and association analysis with Hepatitis B virus (HBV) infection.

Human TNFRSF5, a key signaling molecule expressed by antigen-presenting cells of the immune system, might have associations with autoimmune diseases and various infectious diseases. In the present study, we screened single-nucleotide polymorphisms (SNPs) in TNFRSF5 and examined whether they are risk factors for persistent HBV infection or disease severity. We resequenced all 9 exons, the promoter and splicing regions of all introns for 186 Chinese individuals, and identified 11 SNPs. Haplotypes and their frequencies were estimated. The linkage disequilibrium (LD) pattern was also evaluated. Neutrality tests indicated that the variation pattern at TNFRSF5 locus departs from neutrality and may be maintained by positive selection or demography factors such as population growth. Three SNPs (g.53031T>C, g.54068T>C and g.64493A>G) were determined as haplotype-tag SNPs (htSNPs). Furthermore, computer analyses indicated that sequences surrounding g.53031T>C and g.53824T>C were potential binding sites for transcription factors Sp1 and H4TF-2, respectively. We then genotyped these four SNPs for 603 persistent HBV infection patients and 384 spontaneously recovered subjects by PCR direct sequencing. No statistically significant associations were observed between any of the SNPs or haplotypes and persistent HBV infection or disease severity. The information from this study of the TNFRSF5 would be useful for genetic studies of other common diseases.

Adult↗

PubMed2004

Differential expression profiling of human pancreatic adenocarcinoma and healthy pancreatic tissue.

Due to poor prognosis and lack of effective treatment, pancreatic carcinoma (PC) is a devastating disease. With the goal of contributing to an improved detection, prevention and treatment of the disease, a comparative proteome analysis of PC and normal tissue was carried out. Paired tissue extracts from 12 patients (pancreatic adenocarcinoma and adjacent healthy tissue) were separated by two-dimensional electrophoresis. Differential protein expression was analyzed by gel comparison with the help of image analysis software. The differentially expressed spots were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Seventy proteins were more strongly expressed (mostly two-fold or more) in cancerous tissue, while 41 were stronger in normal pancreas respectively. Those spots highly expressed in PC were confirmed in gels from independent individual samples. Among them were several cytoskeletal proteins, small GTP-binding proteins, and members of the S100 protein family etc. Nine proteins had been reported in previous nuclear acid-based studies. The levels of two proteins were confirmed by immunohistochemistry. One of them, fascin, was detected in 13 out of 21 carcinoma and negative in all normal pancreas samples. Moreover, fascin expression was related to the differentiation of pancreatic carcinoma.

Adenocarcinoma↗

PubMed2004

No association between polymorphisms in three genes of cytochrome p450 family and paranoid schizophrenia in northern Chinese Han population.

We genotyped six SNPs in the genes of p450 family among paranoid schizophrenics and normal controls. All subjects are unrelated Han Chinese. Three showed polymorphic, and no significant differences in allele or genotype frequencies were detected between patients and controls. Thus we obtained no evidence for the involvement of the polymorphisms in paranoid schizophrenia in the population investigated.

Adult↗

PubMed2004

An association study between polymorphisms in three genes of 14-3-3 (tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein) family and paranoid schizophrenia in northern Chinese population.

We performed an association study between three SNPs in the genes of 14-3-3 family and paranoid schizophrenia. SNP rs983583 G/A in the YWHAZ gene showed significant association with paranoid schizophrenia. Our study indicated that the YWHAZ gene was a potential susceptibility gene for paranoid schizophrenia in the population studied.

Adult↗

PubMed2004

Effects of a community-based sex education and reproductive health service program on contraceptive use of unmarried youths in Shanghai.

PURPOSE: To evaluate the effectiveness of a youth-friendly intervention in promoting one safe sex behavior-contraception and condom use among unmarried young people aged 15-24 years in Shanghai, China. METHODS: The study was conducted in two towns of a suburban area of Shanghai (one as the intervention and the other as the control), with comparable socio-cultural-economic and demographic characteristics. The intervention intended to build awareness and offer counseling and services related to sexuality and reproduction among unmarried youths, in addition to the routine program activities, which were exclusively provided in the control site. Baseline surveys were conducted in both sites before the implementation of the intervention, and similar surveys were conducted in both sites 20 months after the intervention had been initiated to test the feasibility and effectiveness of the intervention. In total, 1220 unmarried young people from the intervention site and 1007 from the control site, including 1304 out-of-school youths and 923 high school students, were recruited, and about 92% of them were successfully followed up. Four main measures were examined (i.e., ever contraceptive use, current regular contraceptive use, ever condom use, and contraceptive use at onset of sexual intercourse-if it occurred during the course of the intervention). The reasons for nonuse of contraceptives, the status of joint decision on contraception and the first method used were also assessed. Data were analyzed using Logistic regression models with dichotomous measures of contraceptive use and Generalized Estimating Equations (GEEs) with repeated measures. RESULTS: At baseline, there was no statistical difference in contraceptive use between the intervention and control groups. After intervention, the proportions reporting regular contraceptive use and condom use in the intervention group were much higher than that in the control group (p <.001). A group x time interaction effect (p <.0001) was found for regular contraceptive use and ever condom use. Logistic regression analysis with dichotomous measures of contraceptive use and GEEs with repeated measures showed similar results. The regular contraceptive use and ever condom use were correlated with subject's occupation and family economic status, respectively. After adjusting for demographic factors, the subjects from the intervention group were 14.58 (OR) times as likely to use contraceptives at onset of intercourse as those from the control group (95%CI: 8.55-24.87, p <.0001). Similar results were found for both females and males. CONCLUSIONS: A multifaceted intervention program that provided information and skills, as well as counseling and services, appears to have positive influences on contraceptive practice and condom use among unmarried young females and males in suburban Shanghai.

Adolescent↗

PubMed2004

Enhanced photoluminescence of morin-bovine serum albumin on porous anodized aluminum oxide.

In this paper, the photoluminescence (PL) of porous anodized aluminum oxide (AAO) impregnated with essentially nonfluorescent morin and morin-bovine serum albumin (BSA) was investigated for the first time, respectively. The evident PL bands similar to that of morin-Al3+ complex in solution were observed and the intensity of the latter with morin-BSA was much greater than that of the former with only morin. Moreover, the enhancement increased with the larger pore diameter of the AAO membranes. The appearance of PL bands might be ascribed to the formation of morin-Al complexes in the AAO pores with its inner wall involved. A likely orderly luminescent model was proposed to be responsible for the observed enhancing phenomena of PL due to the coexistence of morin and BSA in the AAO pores.

Aluminum Oxide↗

PubMed2004

Polymorphisms in PLIN and hypertension combined with obesity and lipid profiles in Han Chinese.

The current study investigated the association between PLIN polymorphisms and the combination of hypertension and obesity (HO) and the related clinical features. The polymorphisms 1237 (T/C), 1243 (C/T), and 1323 (C/G) were genotyped in 503 cases with HO and 511 unrelated controls. No associations between polymorphism 1237 (T/C) or 1243 (C/T) and HO were found. However, total cholesterol (TC) levels were significantly different among genotypes of polymorphism 1243 (p = 0.023, power = 0.55). In male cases, 1243T carriers (TT + CT) had higher TC, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol levels compared with CC homozygote carriers (5.23 +/- 0.88 vs. 4.98 +/- 0.90, p = 0.024; 1.13 +/- 0.23 vs. 1.07 +/- 0.22 mM, p = 0.034; 3.3 +/- 0.78 vs. 3.11 +/- 0.80, p = 0.03, respectively). Additionally, 1243T allele carriers were more prevalent among the subjects with both HO and elevated TC levels (> or =5.2 mM) than those with HO and optimal TC levels (<5.2 mM) (chi(2) = 8.53; p < 0.003; odds ratio, 1.69; 95% confidence interval, 1.19 approximately 2.42). Multiple logistic regression analysis suggested a significant contribution of polymorphism 1243 to the elevated TC levels after controlling for conventional risk factors (odds ratio, 1.48; 95% confidence interval, 1.14 approximately 1.91; p = 0.003). Polymorphism 1243 in the PLIN gene did not seem to be associated with HO but with TC levels in Chinese. The PLIN gene may be involved in human lipid metabolism.

Adult↗

PubMed2004

Mutation analysis of five candidate genes in Chinese patients with hypospadias.

Hypospadias is the displacement of the urethral meatus from the tip of the glans to the ventral side of the phallus. During fetal development, SRY, SOX9, WT1, SRD5A2 and AR are important at different stages in the differentiation and development of the male genital system. Mutations in these genes impair masculinization and may be associated with hypospadias. In order to explore these possibilities, we employed polymerase chain reaction and direct sequencing to analyze the coding regions of these five genes in 90 Chinese hypospadias patients. We found a total of 16 different mutations in SRD5A2, AR and WT1 in 24 of these 90 patients. Seven mutations are novel. No mutation was found in SRY or SOX9. SNP V89L found in SRD5A2 was statistically significant between patients and controls. Our results indicated that mutations in SRD5A2, AR and WT1 were associated with hypospadias. In conclusion, mutations are frequently found in genes that control androgen action and metabolism, but are seldom found in genes active in the early phase of sex determination and differentiation. Mutations in AR, SRD5A2 or WT1 seem to be associated not only with hypospadias but also with micropenis.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

PubMed2004

Is NOTCH4 associated with schizophrenia?

The NOTCH4 locus was reported to be associated with schizophrenia in our previous study but the subsequent replication by other workers has been inconsistent. To find out possible reasons for the poor replication, the present work was undertaken to analyse four functional single nucleotide polymorphisms (SNPs) (rs367398, rs915894, rs520692 and rs422951) at the NOTCH4 locus among 141 schizophrenic family trios of Chinese Han descent. Of these four SNPs, rs520692 was the only one associated with schizophrenia (P = 0.017); the other three, however, did not show any association with the illness, including rs367398 located in the promoter region, which had shown a strong association with the illness in our previous study conducted with British samples. Although these four SNPs analysed lie within a less than 4 kb segment of genomic DNA, the pattern of linkage disequilibrium between them was unexpected. The strongest linkage disequilibrium was shown only between rs367398 and rs520692 and between rs520692 and rs422951 in both parent and patient groups. This study raises the possibility that there might be two or more disease-underlying variants at the NOTCH4 locus or at a nearby locus, and that the allelic or locus heterogeneity may be one of the possible reasons for the poor replication of the NOTCH4 finding.

Adult↗

PubMed2004

No association between polymorphisms in the DDC gene and paranoid schizophrenia in a northern Chinese population.

Several lines of evidence suggest that dysfunctions of neurotransmitters are associated with schizophrenia. DOPA decarboxylase (DDC) is an enzyme involved directly in the synthesis of dopamine and serotonin, and indirectly in the synthesis of noradrenaline. Therefore, the DDC gene can be considered a candidate gene for schizophrenia. We performed an association study between three single nucleotide polymorphisms in the DDC gene and paranoid schizophrenia. However, in our study no significant differences were found in the genotype distributions and allele frequencies between 80 paranoid schizophrenics and 108 controls for any of the polymorphisms. Neither did the haplotypes of the single nucleotide polymorphisms show any association with paranoid schizophrenia. Therefore, we conclude that the polymorphisms studied do not play a major role in paranoid schizophrenia pathogenesis in the population investigated.

Asian People↗

PubMed2004

Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells.

Severe acute respiratory syndrome coronavirus (SARS-CoV) is the pathogen of SARS, which caused a global panic in 2003. We describe here the screening of Chinese herbal medicine-based, novel small molecules that bind avidly with the surface spike protein of SARS-CoV and thus can interfere with the entry of the virus to its host cells. We achieved this by using a two-step screening method consisting of frontal affinity chromatography-mass spectrometry coupled with a viral infection assay based on a human immunodeficiency virus (HIV)-luc/SARS pseudotyped virus. Two small molecules, tetra-O-galloyl-beta-D-glucose (TGG) and luteolin, were identified, whose anti-SARS-CoV activities were confirmed by using a wild-type SARS-CoV infection system. TGG exhibits prominent anti-SARS-CoV activity with a 50% effective concentration of 4.5 microM and a selective index of 240.0. The two-step screening method described here yielded several small molecules that can be used for developing new classes of anti-SARS-CoV drugs and is potentially useful for the high-throughput screening of drugs inhibiting the entry of HIV, hepatitis C virus, and other insidious viruses into their host cells.

Animals↗

PubMed2004

Coxsackievirus group B type 3 infection upregulates expression of monocyte chemoattractant protein 1 in cardiac myocytes, which leads to enhanced migration of mononuclear cells in viral myocarditis.

Coxsackievirus group B type 3 (CVB3) is an important cause of viral myocarditis. The infiltration of mononuclear cells into the myocardial tissue is one of the key events in viral myocarditis. Immediately after CVB3 infects the heart, the expression of chemokine(s) by infected myocardial cells may be the first trigger for inflammatory infiltration and immune response. However, it is unknown whether CVB3 can induce the chemokine expression in cardiac myocytes. Monocyte chemoattractant protein 1 (MCP-1) is a potent chemokine that stimulates the migration of mononuclear cells. The objective of the present study was to investigate the effect of CVB3 infection on MCP-1 expression in murine cardiac myocytes and the role of MCP-1 in migration of mononuclear cells in viral myocarditis. Our results showed that the expression of MCP-1 was significantly increased in cardiac myocytes after wild-type CVB3 infection in a time- and dose-dependent manner, which resulted in enhanced migration of mononuclear cells in mice with viral myocarditis. The migration of mononuclear cells was partially abolished by antibodies specific for MCP-1 in vivo and in vitro. Administration of anti-MCP-1 antibody prevented infiltration of mononuclear cells bearing the MCP-1 receptor CCR2 in mice with viral myocarditis. Infection by UV-irradiated CVB3 induced rapid and transient expression of MCP-1 in cardiac myocytes. In conclusion, our results indicate that CVB3 infection stimulates the expression of MCP-1 in myocardial cells, which subsequently leads to migration of mononuclear cells in viral myocarditis.

Animals↗

PubMed2004

[Causes and management of respiratory complication after liver transplantation].

OBJECTIVE: To identify the causes of respiratory complications following liver transplantation (LT) and to discuss the management of these complications. METHODS: One hundred and twenty four cases with pulmonary complications in the first two weeks after LT were identified among 163 patients admitted to the First Affiliated Hospital, College of Medicine, Zhejiang University from February, 1999 to March, 2003. RESULTS: The incidence rate of complications was 76%(124/163) with the total cure rate of 92%(114/124). The cure rates of the various complications were as follows: pleural effusion 100%(113/113), pneumonia 92%(76/83), respiratory insufficiency 91%(59/65), pulmonary hypertension 98%(101/103), pulmonary edema 98(58/59), atelectasis 100%(4/4) and pneumothorax 100%(2/2). CONCLUSION: To drainage the pleural effusion with an unicameral venous catheter is safety and effective. To cure or prevent pneumonia and atelectasis, aseptic manipulating, aspiration of sputum and keeping respiratory channel open were the key measurements of treatment. Restrictive ventilatory functional disturbance (RVFD) and dysfunction of ventilation are two major types of respiratory insufficiency in early stage of post-transplantation. The causes of pulmonary hypertension and edema are associated with pulmonary angiotasis and blood flow volume, and the vasodilator and diuretic often introduced in the therapy.

Female↗

PubMed2004

Effect of basic fibroblast growth factor and hyaluronic acid on proliferation of rabbit chondrocytes in vitro.

OBJECTIVE: To investigate the effect of basic fibroblast growth factor (bFGF) and hyaluronic acid (HA) on the proliferation of rabbit chondrocytes in vitro. METHODS: Chondrocytes from the knee joints of New Zealand white rabbits were cultured. bFGF or HA or both were added into the culture medium respectively, and the proliferation of the chondrocytes was measured with MTT 3-(4, 5-dimethylthiazol-2-yl) 2, 5-diphenyl-tetra-zolium bromide. (MTT, Sigma, M2128). RESULTS: Basic fibroblast growth factor (10 ng/ml) with low concentration of fetal bovine serum in the culture medium promoted the proliferation of chondrocytes significantly, and this effect reached its maximum when concentration of bFGF reached 50 ng/ml. HA itself had no effect on the proliferation of chondrocytes. However, when bFGF was used in combination with HA, especially when the concentration of bFGF was 50-500 ng/ml and that of HA was 10-50 ng/ml, the effect on the proliferation of chondrocytes was much more than when bFGF or HA was used alone. CONCLUSIONS: bFGF can promote the proliferation of chondrocytes. HA, which has no effect on the proliferation of the cells, can maintain a normal growth of chondrocytes. When bFGF is used in combination with HA, more proliferation is obtained.

Analysis of Variance↗

PubMed2004

Genetic and environmental factors associated with plasma paraoxonase activity in healthy Chinese.

To characterize factors associated with plasma paraoxonase 1 (PON1) activity in healthy Chinese Han population, we carried out the present study, not only taking into account the total set of frequent polymorphisms present in PON1 gene in the Chinese Han population, but also some environmental factors. The -107T/C polymorphism as well as drinking and smoking were independently associated with plasma PON1 activity, determined by rates of phenylacetate hydrolysis. The -107T/C polymorphism had the predominant effect and accounted for 16% of the observed variability in plasma PON1 activity. Alcohol consumption can modulate the effects of cigarette smoking on PON1 activity, and smoking only decreases PON1 activity in non-drinkers. The increase of PON1 activity by drinking or the inhibition of PON1 activity by smoking varies according to PON1 -107T/C genotypes, and the associations were only observed in -107T allele carriers. The results illustrate the complexity of polymorphism-phenotype associations. The observed interactions constitute concrete examples of gene-environment and environment-environment interactions.

Adult↗

PubMed2004

Prevention and treatment of hepatic artery thrombosis after liver transplantation.

BACKGROUND: Hepatic artery thrombosis (HAT) which is a serious complication after orthotopic liver transplantation (OLT) remains a significant cause of graft loss. The purpose of this study was to sum up our experiences in the prevention, diagnosis and management of HAT after liver transplantation. METHODS: From April 1993 to September 2003, a total of 198 patients underwent OLT at our hospital. The hepatic artery was anastomosed using 7/0 prolane with running continuous suture in 96 patients (group 1) and with interrupted suture in 102 (group 2). Ultrasonography was performed every day in two weeks after operation and selectively afterwards. RESULTS: HAT occurred in 6 patients (6.3%, 6/96) of group 1, and in 1 (1%, 1/102) of group 2 (X2=4.027, P=0.045). Six patients received emergency thrombectomy, and 1 conservative therapy but died from tumor recurrence eventually. Biliary complication developed in 3 patients after thrombectomy of whom 2 died of liver failure and one waited for retransplantation. In the other 3 patients after thrombectomy, 1 died of renal failure, and 2 survived. The mortality of patients with HAT was 57.1% (4/7). CONCLUSIONS: The technique of hepatic arterial anastomosis is the key factor for the prevention of HAT. Routine ultrasonography is very important in early detection of HAT after OLT. Biliary complication is a severe outcome secondary to HAT.

Adult↗

PubMed2004

[Single nucleotide polymorphisms of growth hormone receptor gene in Chinese Han ethnic population].

OBJECTIVE: To analyze the distribution of single nucleotide polymorphisms (SNP) of growth hormone receptor (GHR) gene in Chinese Han ethnic population. METHODS: The sample of 106 unrelated healthy Chinese Hans was studied by sequencing exons of the GHR gene to detect SNP. RESULTS: There were 6 SNP spots identified in exon 6 and exon 10. Five of them were found in exon 10, and one in exon 6. There were differences between the allele frequencies of the SNP we found and those in the NCBI database. The highest heterozygosity of the SNP was found at 1630 A > C (I526L), which was 47.6%. The SNP 1483 A > C (P477T), 1735 A > C (P561T) and 1319 G > T (C422F) had polarity change. The SNP 536 A > G in exon 6 from the NCBI database was not detected in this population. The allele distribution of SNP was in good unity with the Hardey-Weinberg equilibrium. CONCLUSION: It is suggested that the SNP of GHR are unevenly distributed and different in different ethnic populations.

Asian People↗

PubMed2004

[Analysis on association between the polymorphisms in apolipoprotein E, interleukin-1 alpha genes and Alzheimer's disease in Chengdu area].

OBJECTIVE: To investigate the correlation between the polymorphisms of apolipoprotein E(APOE), the interleukin-1 alpha (IL-1 alpha ) genes and the susceptibility to Alzheimer's disease(AD). METHODS: Association study was performed in 114 AD patients and 113 healthy elderly individuals from Chengdu, China. Polymorphisms of APOE and IL-1 alpha genes were analyzed with polymerase chain reaction-restriction fragment length polymorphism. RESULTS: The frequency of APOE-epsilon 4-carrying genotype in moderate to severe AD patients (28.6%) was higher than that of mild patients (18.5%) and the controls (14.2%), and the difference between moderate to severe AD group and the control group was significant (OR=2.4, 95%CI: 1.1-5.5). The frequency of epsilon 4 was also of significant difference between the group of moderate to severe dementia and the control group (OR=2.6, 95%CI: 1.3-5.3). However, no significant difference in distribution of IL-1 alpha polymorphism between AD patients and controls was observed. CONCLUSION: The APOE epsilon 4 allele was associated with moderate to severe AD while no association between the IL-1 alpha gene polymorphism and AD was found.

Alzheimer Disease↗