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Biomedical subjects

S Wang

Publications and source records attributed to S Wang.

At least 721 records · Page 40Linked to original sources
PubMed1999

[The relationship between polymorphism of LMP2 and LMP7 genes and the phenotype of ankylosing spondylitis].

OBJECTIVE: To evaluate the relationship of the polymorphism of LMP2 and LMP7 genes and the phenotype of patients with ankylosing spondylitis(AS). METHODS: One hundred and eighteen blood samples were collected from patients with AS and acute anterior uveitis(AAU). HLA-B(27) typing was performed and LMP2 and LMP7 amplified fragment length polymorphisms were determined after PCR and digestion with Cfo I restriction enzyme in the study. RESULTS: There was a significantly increased LMP2 BB genotype frequency in patients with AS+AAU(86.9%) and AAU(87%), compared with controls(53.3%) and AS patients(63.1%)(P<0.05); the odds ratio(OR) relating LMP2 BB and AAU was 5.83, and the OR for AS+AAU was 3.71. No difference was found between adult AS and junior AS and between AS patients with and without extraspinal arthritis. No difference was found in LMP7 genotype. CONCLUSION: The polymorphism of LMP2 gene is strongly associated with the development of AAU in AS patients and in uncomplicated AAU patients, but not with the age at onset and the type of joints affected.

Adolescent↗
PubMed1999

[The relationship between apolipoprotein E gene polymorphism and coronary heart disease and arteriosclerotic cerebral infarction].

OBJECTIVE: To detect the relationship between ApoE gene polymorphism and coronary heart disease(CHD), arteriosclerotic cerebral infarction(ACI). METHODS: Exon 4 of ApoE gene was analyzed in normal group(87 cases), CHD group(78 cases) and ACI group(55 cases) by a combination of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct AgNO(3) staining technique. RESULTS: Between the control group and CHD group, ACI group, chi(2) test showed no significant difference in genotype of E3/E3 (P>0.5, P>0.1, respectively); while mu test showed no significant difference in allele epsilon(2)(P>0.25, P>0.1, respectively), epsilon(4)(P>0.1, P>0.25, respectively) of ApoE. CONCLUSION: No relationship between ApoE gene polymorphism and CHD and ACI was noted in this study.

Apolipoproteins E↗
PubMed1999

Effect of dexamethasone on cardiovascular response induced by norepinephrine in nucleus tractus solitarii.

AIM: To study the effect of dexamethasone on cardiovascular response induced by norepinephrine (NE) in nucleus tractus solitarii (NTS). METHODS: The variations of cardiovascular action caused by these drugs were observed after injection of mifepristone (Mif), dexamethasone (Dex), bicuculline (Bic), and NE into the medial and intermediate NTS. RESULTS: Microinjection of Dex (0.39 mmol.L-1, 0.1 microL) into the medial and intermediate NTS abolished the vasodepressed response to NE (8 mmol.L-1, 0.1 microL) microinjected into the same area 10 min later, and the inhibition did not disappear until 4 h. The rapid inhibitory effects of Dex on NE vasodepression was not antagonized by Mif (4.66 mumol.L-1, 0.1 microL), but it was blocked by Bic (3.24 mumol.L-1, 0.1 microL). CONCLUSION: Dex abolished cardiovascular response to NE microinjected into NTS which may be mediated by GABAA receptor.

Animals↗
PubMed1999

Tissue selectivity of antidiabetic agent nateglinide: study on cardiovascular and beta-cell K(ATP) channels.

Nateglinide (NAT) stimulates insulin secretion from pancreatic beta-cells by closing K(ATP) channels. Because K(ATP) channels are widely distributed in cardiovascular (CV) tissues, we assessed the tissue specificity of NAT by examining its effect on K(ATP) channels in enzymatically isolated rat beta-cells, rat cardiac myocytes, and smooth muscle cells from porcine coronary artery and rat aorta with the patch-clamp method. The selectivity of known antidiabetic agents glyburide (GLY) and repaglinide (REP) was also studied for comparison. NAT was found to inhibit K(ATP) channels in the cells from porcine coronary artery and rat aorta with IC(50)s of 2.3 and 0. 3 mM, respectively, compared with 7.4 microM in rat beta-cells, indicating a respective 311- and 45-fold selectivity (p <.01) for beta-cells. With an IC(50) of 5.0 nM in beta-cells, REP displayed an approximately 16-fold (p <.05) selectivity for beta-cells over both types of vascular cells. GLY was nonselective between vascular and beta-cells. At equipotent concentrations (2x respective IC(50)s in beta-cells), NAT, GLY, and REP all caused 62% reduction of pancreatic K(ATP) current but a respective 39, 55, and 66% inhibition of cardiac K(ATP) current. These data collectively indicate that NAT, when compared with GLY and REP, at concentrations effective in stimulating insulin secretion is least likely to cause detrimental CV effects via blockade of CV K(ATP) channels.

Animals↗
PubMed1999

Amplification of calcium signals at dendritic spines provides a method for CNS quantal analysis.

It has been proposed that the small volume of a dendritic spine can amplify Ca2+ signals during synaptic transmission. Accordingly, we have performed calculations to determine whether the activation of N-methyl-D-aspartate (NMDA) type glutamate receptors during synaptic transmission results in significant elevation in intracellular Ca2+ levels, permitting optical detection of synaptic signals within a single spine. Simple calculations suggest that the opening of even a single NMDA receptor would result in the influx of approximately 310 000 Ca2+ ions into the small volume of a spine, producing changes in Ca2+ levels that are readily detectable using high affinity Ca2+ indicators such as fura-2 or fluo-3. Using fluorescent Ca2+ indicators, we have imaged local Ca2+ transients mediated by NMDA receptors in spines and dendritic shafts attributed to spontaneous miniature synaptic activity. Detailed analysis of these quantal events suggests that the current triggering these transients is attributed to the activation of <10 NMDA receptors. The frequency of these miniature synaptic Ca2+ transients is not randomly distributed across synapses, as some synapses can display a >10-fold higher frequency of transients than others. As expected for events mediated by NMDA receptors, miniature synaptic Ca2+ transients were suppressed by extracellular Mg2+ at negative membrane potentials; however, the Mg2+ block could be removed by depolarization.

Animals↗
PubMed1999

Activation of cyclins and cyclin-dependent kinases, DNA synthesis, and myocyte mitotic division in pacing-induced heart failure in dogs.

The inability of myocytes to reenter the cell cycle in vitro may result from a block in the activation of cyclins and cyclin-dependent kinases (cdk). This inhibition may not occur in vivo because myocyte proliferation is present in the failing heart. Thus, cardiac failure was induced by ventricular pacing in dogs, and changes in the quantity of cyclin D2, cyclin A, cyclin B, cdk2, and cell-division cycle-2 (cdc2) in control and paced myocytes were measured. The kinase activity of these nuclear proteins was also established. Finally, DNA synthesis and mitotic indices in myocytes were evaluated. Cyclin D2 in myocytes increased 7-fold after pacing, and cyclin D2-associated kinase activity increased 3-fold. Similarly, cyclin A quantity and activity increased 4-fold. Comparable changes were observed for cyclin B. cdc2 protein increased 8-fold, and cdk2 and cdc2 activity increased 3-fold and 5-fold, respectively. DNA synthesis was detected in 556 myocyte nuclei/10(6) and 2,467 myocyte nuclei/10(6) in control and paced hearts, respectively. Corresponding mitotic indices were 16/10(6) and 95/106, respectively. In conclusion, myocytes react to cardiac failure by activating cyclins and cdk, which are coupled with cell regeneration and the recovery of muscle mass.

Animals↗
PubMed1999

[Detection of S-gene mutation strain in vertical transmission of HBV and its significance].

OBJECTIVE: To study S-gene mutation of hepatitis B virus (HBV) in its vertical transmission and its significance. METHODS: Nucleotides of S-gene NT451-660 of HBV were sequenced with dideoxy end termination technique in four female and six male carriers without HBV markers in their spouses and in their intrauterine infected fetuses. RESULTS: It was showed that homology of HBV nucleotide and amino acid sequences in the mothers, fathers and their fetuses was very high. Mutation at the sites 491, 494, 530, 546 and 581 of S-gene resulted in amino acid substitution at the sites 113, 114, 126, 131 and 143, respectively. Mutations at the sites 126 were detected in two pairs of mother or father and her or his fetuses and mutations at the sites 131 in four fetuses, respectively, including combined mutation at the site 143 in two fetuses. CONCLUSION: Strains with S-gene mutation, mainly at the sites 126, 131 and 143, could be found in HBV vertical transmissions, which could cause failure in HB vaccine immunization.

Adult↗
PubMed1999

[Epidemiological analysis of the fires happened in China from 1950 to 1994].

OBJECTIVE: Approaching the harmful factors and the preventive steps of fires for controlling and preventing fires from harming people. METHOD: Descriptive analysis was used to review 2,905,504 fires-cases in China from 1950 to 1994. RESULTS: On average, there were 3,432 people died and 6,726 injured in 64,567 fires per year. From the middle of 70's, the means of injured and death rates decreased slightly, but have gone up a little after 80's. The economical loss has risen greatly year after year, reaching the maximum of 1.3 billion Yuan (RMB) in 1994. The loss of a fire case in 1994 was more than twice than that in 1990. 89.4% fires were caused by man's faults. The fire cases in Sichuan, Yunnan, Jiangshu, Zhejiang and Guangdong Provinces were more serious than the average, of which Guangdong was the worst. Data from 17 departments showed that, the fire frequency in residential quarters of cities and countryside were highest (24%), and the number of injury and death accounted for 28.4%. The fire happens frequently in winter, and least in summer. CONCLUSIONS: The problem caused by accounted fire has not been controlled effectively.

Burns↗
PubMed1999

[HBV transmission from father to foetus and HBV DNA in tissues outside the liver].

OBJECTIVE: To study the possibility of HBV Transmission from father to foetus and HBV DNA in tissues outside liver. METHODS: Paired sera were from 8 HBV man carriers whose wives were negative for HBVM and 8 foetuses who were infected with HBV in the womb. S gene nt 451-660 nucleotide, C gene nt 2,022-2,321 nucleotide were directly sequenced. RESULTS: The homology of HBV sequence between father and foetus was very high. The mutations of 491, 494, 530, 546 and 581 nucleotide in the S gene caused 113, 114, 126, 131 and 143 amino acid substitution. HBV DNA can be detected in the tissues outside liver of foetus. CONCLUSION: HBV transmission from father to foetus may be present. HBV DNA in tissues outside liver of foetus can be detected.

Adult↗
PubMed1999

Evaluation of recombinant chitinase antigen in serological diagnosis and surveillance of lymphatic filariasis.

Apply recombinant chitinase fusion protein antigen, enzyme-linked immunosorbent assays examined anti-filarial antibodies and evaluated of useful value in serological diagnosis and surveillance of lymphatic filariasis. The test jirds were immunized and infected by chitinase and B. malayi third stage larvae respectively. Functional protein molecular of chitinase was analyzed by SDS-PAGE, Western blot. The result shown that jirds from microfilaremia (mf) and donors with Mf were directly to react with chitinase antigen that positive rate was 100%, but Mf-xt antigen was only 80%. Normal jirds and persons sera from unepidemic control donors all were negative. False positives of 5% and 20% reacted with chitinase and Mf-xt antigens respectively. The results indicate that recombinant chitinase antigen is suitable for detection of active occult or patent lymphatic filariasis with daytime blood samples in residents of endemic areas, is easy to be performed and inexpensive.

Animals↗
PubMed1999

The third lumbar transverse process syndrome treated by electroacupuncture at huatuojiaji points.

32 cases of the third lumbar transverse process syndrome were treated mainly by electroacupuncture at Huatuojiaji points of the first and second lumbar vertebrae, and another 30 cases of the syndrome by conventional acupuncture as the controls. The results showed that treatment by electroacupuncture at Huatuojiaji points was superior in analgesic effect and clinical total effective rate to that by conventional acupuncture. It is considered that the mechanism of treatment by electroacupuncture at Huatuojiaji points is related to the trunk of posterior ramus of the spinal nerve where the points are located.

Acupuncture Points↗
PubMed1999

[Association of glucokinase gene with gestational diabetes mellitus in Chinese].

OBJECTIVE: To evaluate the role of glucokinase(GCK) gene in the pathogenesis of gestational diabetes mellitus (GDM) in Chinese. METHODS: Two microsatellite polymorphisms, GCK1 and GCK2 which located at approximately 10 Kb 3' and 6 Kb 5', respectively, of the human glucokinase gene on chromosome 7p13, were genotyped in 40 unrelated gestational diabetics and 43 controls. RESULTS: Four alleles (A, B, C, D) and seven genotypes were identified at the GCK1 locus. There was no significant difference in allele and genotype frequency between GDM and control groups at the GCK1 locus. For GCK2, four alleles(1,2,3,4) and eight genotypes were detected. When compared with control subjects, the GDM group had a much less frequency of the allele 2 (51.3% vs 69.8%, chi 2 = 5.965, P = 0.015), and a much more frequency of allele 3(31.3% vs 17.4%, chi 2 = 4.321, P = 0.038). Nine haplotypes of GCK1 and GCK2 were observed and haplotype B/2 was much less in GDM group(1.9% vs 19.4%, RR = 0.078 6, P = 0.003). Among the GDM patients, comparing with carriers of other alleles, the carriers of allele 3 of GCK2 locus had significantly elevated fasting and 2 hour's blood glucose levels during OGTT, and their insulin levels at 2nd and 3rd hour during the OGTT test were significantly decreased. Our results suggest that GCK gene was associated with Chinese GDM, and haplotype of GCK1/GCK2 B/2 was a protective factor for GDM.

Adult↗
PubMed1999

[Epidemiological analysis on the risk factors of intrauterine transmission of hepatitis virus C].

OBJECTIVE: To investigate the possibility and risk factors of intrauterine transmission of hepatitis virus C (HCV) in Taiyuan City. METHODS: Anti-HCV and HCV RNA were detected by enzyme linked immunosorbent assay(ELISA) and reverse transcriptase Polymerase Chain Reaction(RT-PCR), in 64 mothers with HCV or HCV RNA positive and their newborns cord blood samples. Case-control study was used for the risk factors analysis. RESULTS: The infection rate of HCV was 66.15% in newborns from anti-HCV or HCV RNA positive mothers. The intrauterine transmission rate was 100% in newborns from HCV RNA positive mothers. There was a significant correlation between HCV intrauterine transmission and maternal history of blood transfusion and abnormal serum alanine aminotransferase(ALT), and the relative risk was 317.15 and 2.60, respectively. CONCLUSIONS: The higher incidence of intrauterine transmission was found in newborns from HCV RNA or anti-HCV positive mothers. The high risk factors of intrauterine transmission are maternal blood transfusion history and abnormal ALT.

Antibodies, Viral↗
PubMed1999

[Effects of nitric oxide on platelet function in burned rats].

OBJECTIVE: To investigate the effects of nitric oxide (NO) on rat platelet function after burn injury. METHODS: Wistar rats with 30% TBSA full thickness burns were used as model, indices of platelet functions including platelet aggregation rate in first minute (PAR-1), maximal platelet aggregation rate (PAR-m), platelet dissipation rate (PDR) and platelet adhesion rate (PAR) were determined in four groups, namely burn control (B), NO donor (sin-1), NO synthesis inhibitor (L-NAME) and the normal control (C). RESULTS: The PAR-1, PAR-m and PAR were significantly increased and the PDR was decreased remarkably after burn injury. In sin-1 group the PAR-1, PAR-m and PAR were obviously lower and the PDR was higher than that of B group (P < 0.05-0.01). In L-NAME group the PAR-1 was higher and the PDR was lower as compared with B group, but the PAR-m and PAR showed no significant differences between two groups. CONCLUSIONS: The ability of platelet adhesion and aggregation induced by activated platelet are increased after burn injury. NO can partially reduce the degree of platelet activation and inhibit platelet aggregation. Moreover, it may dissipate aggregated platelets.

Animals↗
PubMed1999

Combination of intraoperative embolization with surgical resection for treatment of giant cerebral arteriovenous malformation.

OBJECTIVE: To reduce the risk of surgical resection of giant arteriovenous malformation (AVM) (> 6.0 cm) and prevent normal perfusion pressure breakthrough (NPPB) for lowering the postoperative mortality. METHODS: During the operation under barbiturate anesthesia, the proximal end of the feeding arteries were ligated at first, and 0.5 ml isobutyl 12-cyanoacrylate (IBCA) with 0.5 ml 5% glucose was injected into the vessels towards the AVM, then the malformed vessels were resected totally. Postoperative digital subtraction angiography of the four vessels was performed in all patients. RESULTS: 50 patients with giant AVM survived after operation, only 6 (12.0%) had transient neurological dysfunction and 44 (88.0%) recovered after a follow-up of 6-36 months. No patient suffered from normal perfusion pressure breakthrough (NPPB). CONCLUSIONS: The embolization could block the arteriovenous shunts sufficiently to decrease the blood flow away from the normal areas of the brain so as to prevent the incidence of intra- and postoperative rebleeding, especially in NPPB. Therefore, the combination of intraoperative embolization with surgical resection is an effective strategy in the treatment of giant cerebral AVMs, which make it operable for those used to be regarded as inoperable cases.

Adolescent↗