Biomedical subjects

S Wang

Publications and source records attributed to S Wang.

At least 541 records · Page 30Linked to original sources

PubMed2000

Reactive oxygen species contribute to the induction of superoxide dismutase during heat shock in cultured rat neonatal cardiomyocytes.

OBJECTIVE: To explore the influence of reactive oxygen species (ROS) during heat shock on the activity of superoxide dismutase (SOD) and the endurance of cardiomyocytes against hypoxia-reoxygenation damage. METHODS: Cultured rat neonatal cardiomyocytes were divided into 5 groups (n = 6/group): normal control, anoxic control, heat shock, heat shock + SOD (150 U/ml) and exogenous ROS pretreated. Myocytes were first incubated in a CO2 incubator (37 degrees C) with Hank's solution for 30 min, followed by specific pretreatment. Heat shock was performed by incubating the cells in a 43 degrees C incubator for 30 min; exogenous ROS were generated by the reaction of xanthine oxidase with xanthine. After the dishes were returned to normal incubation conditions for 24 h, myocytes underwent hypoxia (3 h) and reoxygenation (1 h). RESULTS: Compared with control groups, ROS production increased after the cells experienced heat shock (1.28 +/- 0.34 nmol/mg.1 protein vs 0.80 +/- 0.23 nmol/mg.protein and 0.74 +/- 0.20 nmol/mg.protein, P < 0.05) or ROS pretreatment (3.30 +/- 0.58 nmol/mg.protein, P < 0.05). 24 hours later, accompanied by attenuated cellular injury, significantly increased SOD activity was found in heat shock (2.55 +/- 0.43 U/mg.protein vs 0.77 +/- 0.12 U/mg.protein and 0.63 +/- 0.09 U/mg.protein, P < 0.05) and exogenous ROS pretreated (2.34 +/- 0.31 U/mg.protein, P < 0.05) groups following reoxygenation. Moreover, opposite results were found when myocytes were treated with SOD during heat shock. CONCLUSIONS: The release of ROS during heat shock triggers delayed myocardial protection by altering the activity of SOD. ROS may play an important pathophysiological role in heat shock induced myocardial protection.

Animals↗

PubMed2000

HLA alleles in patients with Guillain-Barre syndrome.

OBJECTIVE: To determine whether genetic factors may work in concert with autoimmune factors in the pathogenesis of Guillain-Barre syndrome (GBS). METHODS: We determined the differences in the distribution of HLA alleles between GBS patients and normal controls. HLA-DQA, -DQB and -DRB alleles were typed by the sequence specific primer polymerase chain reaction (PCR-SSP) methods in 47 GBS, 7 patients with Campylobacter jejuni (CJ) enteritis and 50 normal controls. RESULTS: There were no differences in the frequency of HLA-DQA, -DQB and -DRB among GBS group, CJ group, normal controls and GBS subgroups with respect to recent CJ infection, GM1 IgG and GM1 IgM antibodies (P > 0.05). There was an increasing tendency of DQA1 * 0301 (P = 0.056, RR = 2.991) in the subgroup with GM1 IgG antibodies and DQA1 * 0302 (P = 0.087, RR = 3.587) in the subgroup with recent CJ infection. No difference was found among GBS, CJ enteritis patients and normal controls. CONCLUSIONS: The increasing tendency of the two alleles suggests that there may be some relation between genetic factors and immunological factors, but a definite conclusion waits for more cases.

Alleles↗

PubMed2000

Molecular epidemiologic study of Mycoplasma genitalium infection in high risk populations of sexually transmitted diseases in China.

OBJECTIVE: To detect Mycoplasma genitalium (Mg) infection in high risk populations of sexually transmitted diseases (STDs) from several cities in China and to clarify the possible role of Mg in the pathogenesis of non-gonococcal urethritis. METHODS: Polymerase chain reaction (PCR) based on 2 pairs of primers, one for Mg-Pa (adhesion protein) and the other for 16S-rRNA (Mycoplasma genera) was used to detect Mg infection. Urogenital specimens of different high risk populations and urethritis patients, were collected from the Guangdong, Kunming, Shanghai, Nanjing, and Changzhou areas. RESULTS: The positive detection rate of Mg-DNA in high risk populations of STDs was significantly higher than that of the control group (chi 2 = 7.82, P < 0.01). The positive detection rates in Guangdong STD clinics and promiscuous persons from Kunming were higher than those from the Shanghai, Nanjing, and Changzhou areas (chi 2 = 8.54, P < 0.01 and chi 2 = 5.89, P < 0.05). Mg DNA could be detected in those patients without other relevant pathogens. Some patients were simultaneously infected with Mg and other microbes, such as Chlamydia trachomatis and/or Ureaplasma urelyticum. The positive Mg-DNA detection rate in patients with urethritis symptoms was higher than in patients without the symptoms (chi 2 = 11.68, P < 0.01). CONCLUSION: Mg infection exists in high risk populations of STDs in China, and the Mg infection rate is different among different high risk groups.

Adolescent↗

PubMed2000

Expression of CDKI p27Kip1 in trophoblastic neoplasm.

OBJECTIVE: To evaluate the role of p27Kip1 in tumorigenesis and the development of trophoblastic cell disease. METHODS: Using immunohistochemistry, the expression of p27-protein was investigated in 10 normal chorionic villi in the first trimester of pregnancy, 15 complete hydatidiform moles (HM), 7 invasive moles (IM) and 7 choriocarcinomas (CC). RESULTS: In all cases, immunohistochemical staining localized p27-protein in the plasma. Decreased expression of p27Kip1 was observed in malignant trophoblastic neoplasms with a positive rate of 21.43%, which is significantly less than that in normal chorionic villi (80%) and in complete HM (73.33%) (P < 0.05). The positive rate of p27Kip1 in those complete HM with large uterine size for gestational age was lower than that in those with normal or small uterus (42.86% vs 100%, P < 0.05). CONCLUSION: p27Kip1 may be involved in the tumorigenesis of gestational trophoblastic neoplasm as a negative regulator of the cell cycle. The expression level of p27Kip1 in trophoblastic cells may be a prognostic factor for complete HM.

Cell Cycle Proteins↗

PubMed2000

Advanced glycosylation end products, protein kinase C and renal alterations in diabetic rats.

OBJECTIVE: To study the relationship between advanced glycosylation end products (AGE) and protein kinase C (PKC), and their effects on renal alteration in diabetic rats. METHODS: Insulin or aminoguanidine was administered to diabetic rats. Blood glucose, hemoglobin A1c (HbA1c), glomerular tissue extracts AGE (GTE-AGE), PKC, glomerular basement membrane thickness (GBMT) and urine protein/creatinine (Pr/Cr) ratio in diabetic rats were measured and analysed. RESULTS: Levels of blood glucose, HbA1c and AGE, PKC activity, the Pr/Cr ratio and GBMT were all significantly increased (P values all less than 0.01) in diabetic rats. Insulin could decrease the formation of HbA1c and AGE, and improve PKC activity. Aminoguanidine had no influence on PKC activity (P > 0.05) although it decreased the formation of AGE. Both drugs could delay the increase of urine Pr/Cr ratio and GBMT (P < 0.05 or P < 0.01). CONCLUSIONS: Chronic hyperglycemia may lead to an increase of PKC activity. HbA1c and AGE may not directly contribute to alterations of PKC activity, but the increase of PKC activity could promote the action of AGE on GBM thickening. It is important to inhibit the formation of AGE and reduce the PKC activity so as to prevent or delay the development of diabetic nephropathy.

Animals↗

PubMed2000

[Study on interferon gamma and interleukin-4 contents of plasma and cultured monoclear cell supernatants in patients with endometriosis].

OBJECTIVE: To investigate the cytokin production of T helper cell (Th) 1, Th2 subsets in patients with endometriosis(EM). METHODS: The cytokine production of Th1, Th2 cells expressed by interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) contents respectively in supernatants of cultured PHA induced peripheral blood mononuclear cell (PBMC) and plasma, obtained from 30 EM patients and 15 normal controls were determined by enzyme linked immunoabsorbent assay (ELISA). RESULTS: IL-4 contents of EM patients were elevated both in plasma and PBMC supernatants[(32.0 +/- 22.6) ng/L and (32.8 +/- 12.5) ng/L, respectively], while IFN-gamma levels was suppressed in PBMC supernatant as compared with normal controls [(1,095.6 +/- 375.6) ng/L and (1,549.3 +/- 361.9) ng/L, respectively] (P < 0.01, P < 0.05). As a results, the ratio of IFN-gamma/IL-4 decreased in EM patients. CONCLUSIONS: Changes of IFN-gamma and IL-4 contents in EM patients may reflect functional inbalance between Th1 and Th2 cells, which may play a role in the pathogenesis of EM.

Adult↗

PubMed2000

[The value of serum alpha-L-fucosidase activity in the diagnosis of primary liver cancer].

OBJECTIVE: To analyse the value of serum alpha-L-fucosidase (AFU) in the diagnosis of primary liver cancer (PLC). METHODS: Serum AFU was studied in 141 patients with PLC, 17 patients with secondary liver cancer, 16 patients with cirrhosis, and 30 controls. Rank correlation analysis was used to assess the relation between value of AFU activity and TNM staging. The results were compared to those of serum AFP determination. RESULTS: AFU was increased in 108 of 141 (76.6%) patients. The positive rate was statistically different from that in patients with secondary liver cancer, cirrhosis, and that in normal individual. The AFU level was correlated with TNM stage. In 25 PLC patients with AFU > 500 nmol.L-1.S-1, the average survival time was only 71 days. In 36 PLC patients who had received effective treatment, the serum AFU decreased to a significantly lower level than that examined before treatment. The positive rate of AFP in PLC patients was 64.5%. It rose to 86.2% if both parameters were used. CONCLUSION: AFU is a useful marker of PLC for diagnosis and posttreatment monitoring.

Adult↗

PubMed2000

[Relationship between blast crisis of chronic myeloid leukemias and abnormality of p16 and calcitonin genes].

OBJECTIVE: To study the relationship between homozygous deletions of p16 gene and calcitonin hypermethylation and chronic myeloid leukemia (CML) blast crisis. METHODS: Semiquantitative multiplex polymerase chain reaction (PCR) was used to detect homozygous deletions of p16 gene and semiquantitative PCR to detect calcitonin gene hypermethylation in 53 CML patients. RESULTS: In 53 CML patients, homozygous deletion of p16 gene was found in none of them in chronic phase, while in 6.3% (1/16) of them in myeloid blast crisis, 66.7% (8/12) in lymphoid blast crisis, and 2/5 (40%) in mixed cell blast crisis. Calcitonin gene hypermethylation was found in 10% (2/20), 68.8%(11/16), 16.7%(2/12), and 40% (2/5), respectively. CONCLUSION: There is intimate relationship between homozygous deletions of p16 gene and CML in lymphoid blast crisis, between calcitonin gene hypermethylation and CML in myeloid blast crisis. Moreover, abnormality of both genes may be associated with mixed cell blast crisis in CML patients. Simultaneous detection of the two genes help early pickup CML patients in blast crisis.

Adult↗

PubMed2000

[Carcinoma of the vulva: a report of treatment].

OBJECTIVE: To analyse the outcome of various treatments for vulvar cancer and to investigate the characteristics of the recurrence and metastasis. METHODS: A total of 309 patients with carcinoma of vulva were analyzed retrospectively. RESULTS: The overall 5-year survival rate was 67.9%. That for stage I, II, III and IV was 86.9%, 82.5%, 59.2% and 43.6%, respectively. Treatment failure was seen in 49.8% of the treated cases, and it occurred within 2 years after primary treatment in the majority of the cases. Inguinal and pelvic recurrences, and distant metastases occurred within 2 years, while local recurreuce mostly after 2 years. Recurrence rate was not related to age of the patients. For stage I cancer, there was no difference in the results of different methods of treatment, but for stage II cancer, wide local resection plus inguinal lymphadenectomy was a better choice. In patients with regional lymph node metastases treated by nodal resection, it was less likely to recur than did radiotherapy. If no nodal involvement, the outcome of the two types of treatment was not different. Higher dose of radiation (Dm > or = 60 Gy) was better than lower dose (40-50 Gy) for prevention of recurrence. CONCLUSION: For early stage vulvar cancer, in addition to radical resection of vulva, preventive dissection of inguinal lymph nodes, or full dose radiation of the inguinal region, leads to better therapeutic results. For advanced cases, radical resection of the primary tumor with pre- and post-operative radiation, and inguinal lymph nodal disection, whenever possible, should be performed.

Female↗

PubMed2000

[Detection and significance of interleukin-8,6, tumor necrosis factor-alpha in sputa from patients with chronic obstructive pulmonary disease].

OBJECTIVE: To evaluate the role of cytokines in the pathogenesis of COPD. METHODS: Induced sputum samples were obtained from 20 patients with stable COPD, 10 healthy smokers (HS) and 10 healthy nonsmokers (HNS). Total and differential cell counts were examined, and sputum interleukin (IL)-8, tumor necrosis factor (TNF)-alpha, IL-6 level were measured by radioimmunoassay technique. RESULTS: Sputum IL-8, TNF-alpha level and neutrophil percentages (PMN) in the COPD group were significantly higher than those in the HS group and the HNS group (P < 0.01). Compared with the HNS group, there was a significant increase in the PMN and the level of IL-8 in the HS group (P < 0.05). The sputum level of IL-6 did not differ significantly among three groups (P > 0.05). In the COPD group, the sputum level of IL-8 was correlated positively with the level of TNF-alpha and the PMN (r's = 0.5999, 0.6737). In the HS group the sputum level of IL-8 was also correlated positively with the PMN (rs = 0.8424). The sputum IL-8, TNF-alpha levels and the PMN were all correlated negatively with FEV1% and FEV1/FVC in the COPD group (r's = -0.6453, -0.7341, -0.7341, -0.7624, -0.5262, -0.7353). CONCLUSIONS: IL-8, TNF-alpha and neutrophil are involved in airway inflammation which results in airflow obstruction, thus playing an important role in the pathogenetic process of COPD.

Aged↗

PubMed2000

[Drug susceptibility testing for M. tuberculosis with proportion method].

OBJECTIVE: To analyze the feasibility of proportion method in drug susceptibility testing (DST) of M. tuberculosis(MTB). METHODS: DST was performed to 360 strains of MTB using proportion method and absolute concentration method, 30 of them using both China made and Sigma produced anti-TB drugs. MIC was detected in 19 strains whose results were different from standard ones. RESULTS: In isoniazid (INH) and ethambutol (EMB), the resistance rate and the accordance rate compared with standard results were significantly higher in proportion method than absolute concentration method (P < 0.01). But in streptomycin (SM) and rifampicin (RFP), they did not show any significant difference. The accordance rates of INH, SM, EMB and RFP between two methods were 81.1%, 92.5%, 83.6% and 98.6%. The DST results using China made and Sigma produced anti-TB drugs had no significant difference. CONCLUSIONS: The main reason made proportion method differ from absolute concentration method is critical concentration of drugs. China made anti-TB drugs are also qualified for DST purpose.

Microbial Sensitivity Tests↗

PubMed2000

[Study on beta 2 adrenergic receptor genetic polymorphisms in asthmatics in the people of the Han nationality of northern China].

OBJECTIVE: To analyze the association between beta 2-AR genetic polymorphism and asthma in the people of the Han nationality of northern China. METHODS: Allele Specific-PCR techniques were used to determine 16, 27 and 164 locus alleles of beta 2-AR genetic polymorphisms in 58 unrelated patients with asthma and 89 healthy controls from the people of the Han nationality of northern China. RESULTS: (1) The distribution frequency of genotype beta 2-AR 16 loci: Arg/Arg genotype accounts for 13%, Arg/Gly 76% and Gly/Gly 11%. The beta 2-AR 27 loci: Gln/Gln genotype accounts for 36%, Gln/Glu 55% and Glu/Glu 9%. The beta 2-AR 164 loci: Thr/Thr genotype accounts for 30%, Thr/Ile 53% and Ile/Ile 17%. (2) The frequency of genotype beta 2-AR 16 loci in asthmatics: Arg/Arg genotype accounts for 24%, Arg/Gly 45% and Gly/Gly 31%. There was a significant increase in the frequency of Gly/Gly genotype in asthmatics compared with healthy group(OR = 4.0, 95% CI 1.7-9.7), but there was no significant difference in the allele frequency of asthmatics compared with healthy group. The frequency of genotype beta 2-AR 27 loci in asthmatics: Gln/Gln genotype accounts for 34%, Gln/Glu 56% and Glu/Glu 10%. There was no significant difference in the allele frequency of asthmatics compared with healthy group. The frequency of genotype beta 2-AR 164 loci in asthmatics: Thr/Thr genotype accounts for 10%, Thr/Ile 83% and Ile/Ile 7%. There was no significant difference in the frequency of Ile/Ile genotype in asthmatics compared with healthy group, and in the allele frequency of asthmatics compared with healthy group. In addition, our study reveals that beta 2-AR 16 locus genetic polymorphism is in association with asthmatic severity. CONCLUSIONS: These results suggest that beta 2-AR 16 locus genetic polymorphism is correlated with asthma severity in the people of the Han nationality of northern China.

Adolescent↗

PubMed2000

[Anatomic, sialographic, histologic and ultrastructural studies of normal parotid gland of the miniature pig].

OBJECTIVE: To investigate the morphology of normal parotid gland of the miniature pig (minipig). METHODS: Anatomic, sialographic, histologic and ultrastructural studies of parotid glands were performed in 11 Chinese experimental minipigs. RESULTS: Sialograms showed a long main duct and a triangular shape gland. All branching ducts extended from the inferior-posterior of the main duct. No necessary glands were found. Typical serous acini were found microscopically. CONCLUSIONS: This study provides basic structural information of the parotid gland of the minipig. It is considered that minipig is a useful animal model in the investigation of parotid gland diseases.

Animals↗

PubMed2000

[Clinical observation on ganrening granule in treating common cold].

OBJECTIVE: To explore the therapeutic effect of Ganrening Granule (GRN) in treating common cold. METHODS: Four hundred cases of common cold were randomly divided into three groups, the GRN group (160 Patients), the control group (100 Patients) and the opened group (140 Patients). The changes in symptoms and body temperature of patients were observed before and after treatment by single blind method, and the therapeutic effect was assessed according to the "Guideline of Clinical Research of TCM New Drugs". RESULTS: The markedly effective rate and total effective rate of the GRN group were 81.25% and 96.88% respectively, while those of the control group were 44.44% and 88.00% respectively. The difference between the two groups was significant (P < 0.01). GRN showed significant effect in subsiding fever. CONCLUSION: GRN has good effect in treating common cold (Syndrome of both Weifen and Qifen). No adverse effect was found in the clinical trial.

Adolescent↗

PubMed2000

[beta-fibrinogen gene -455A/G polymorphism and plasma fibrinogen level in Chinese stroke patients].

OBJECTIVE: To explore the relationship between beta-fibrinogen gene -455A/G polymorphism and plasma fibrinogen level and to determine the influence of the mutation on ischaemic stroke. METHODS: Ninety-one patients (63.5 +/- 10.1 years) with ischaemic stroke, 74 control patients (60.6 +/- 10.8 years) without any thromboembolic events and 98 healthy blood donors (37.5 +/- 13.3 years) were enrolled in this trial. beta-fibrinogen gene -455A/G polymorphism was analyzed from all subjects by polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP) with restrictive enzyme Hae III. Plasma fibrinogen levels were obtained from prothrombin time (PT) assay. The parameters were compared between any two different groups by unpaired t-test and Chi-square test. Before the analysis, log transformation was carried out for concentrations of fibrinogen. RESULTS: Frequency of H2 allele was higher in male patients with ischaemic stroke than in control patients (22.7% vs 7.1%, chi(2) = 5.56, P < 0.02). There was no significant difference in female patients. In the subjects without any thromboembolic events (including control patients and healthy blood donors), frequency of H2 decreased with age (>/= 40, 21.3%; 41 approximately 59, 15.4%; >/= 60, 10.0%). Among male control patients and healthy blood donors, the level of plasma fibrinogen was lower in the H1H1 genotype (287 g/L +/- 96 g/L and 234 g/L +/- 58 g/L) than in H1H2 and H2H2 genotypes (331 g/L +/- 44 g/L and 307 g/L +/- 55 g/L; t = 2.53 and 9.67, P < 0.05); among females, this tendency was not found. CONCLUSION: Plasma fibrinogen expression is affected by the beta-fibrinogen gene - 455A/G polymorphism. H2 allele is a risk factor for ischaemic stroke in Chinese men.

Adult↗

PubMed2000

[A comparison of polymerase chain reaction with other two widely used methods in detection of Porphyromonas gingivalis].

OBJECTIVE: To compare the efficiency of polymerase chain reaction (PCR) with cultural method and indirect immunofluorescence (IF) in detection of Porphyromonas gingivalis (P.g) in oral plaque samples. METHODS: 92 subgingival plaque samples were collected from patients of three kinds of periodontal disease. A program using PCR to detect Fimbrilin gene (Fim A) was designed to detect P.g. The efficiency of this PCR method was compared with cultural method and IF. RESULTS: The positive-rate of PCR was 94.6%, while that of cultural method and IF was only 48.9% and 68.5% respectively. The difference was significant in statistical analysis (P < 0.001). CONCLUSION: PCR is more sensitive than culture method and IF in detecting pathogens of periodontal diseases. The study provides a simplified and efficient method for oral clinical use.

Adult↗

PubMed2000

[Expression of VEGF and tumor angiogenesis in bladder cancer].

OBJECTIVE: To evaluate expression of vascular endothelial growth factor (VEGF) and its relation to angiogenesis in bladder cancer. METHODS: The expression of VEGF by immunohistochemical staining was examined in 68 cases of primary transitional carcinoma (TCC) and 7 subjects with normal urothelium. Microvessel density (MVD) in 40 cases of invasive bladder cancer was determined by Factor VIII immunohistochemical staining. RESULTS: The expression of VEGF was negative or low level in all normal bladder tissue but high in bladder cancer. VEGF and MVD were closely related to tumor cell nuclear grade and clinical stage. The average MVD was higher in the cases with the high level expression of VEGF, than in those with the low level expression of VEGF. CONCLUSIONS: This study indicates that VEGF is positively correlated with the occurrence and progression of bladder cancer. VEGF is one of the primary angiogenic factors for bladder cancer, and is able to induce tumor angiogenesis and accelerate tumor growth. Quantification of VEGF may provide a valuable marker for a poorer prognosis of patients.

Adult↗

PubMed2000

[Relationship between new TNM classification and the prognosis and biological behavior of gastric cancer].

OBJECTIVE: To determine the clinical value of 1997 TNM classification of gastric cancer. METHODS: 334 cases of gastric cancer with regional lymph node metastasis were used to determine the relationship between new TNM classification and the prognosis and biological behavior compared with old classification (1987). RESULTS: The 5-year survival rates of the old pN(1), pN(2) were 49.6% and 33.5% respectively; those of the new pN(1), pN(2), pN(3) were 48.5%, 24.1% and 5.6% respectively. There was a highly significant difference in survival in different new pN groups (P < 0.01). The new pN classification was correlated with the depth of cancer invasion, as well as the macroscopic type, growth pattern and serosal type (P < 0.01). Multivariate COX model analysis showed that the new pN classification was the most significant independent prognostic factor. CONCLUSIONS: The new TNM classification is not only an objective, simple and reproducible system, but also a significant prognostic index for gastric cancer superior to the old classification.

Adult↗