Biomedical subjects

S Zhang

Publications and source records attributed to S Zhang.

At least 253 records · Page 14Linked to original sources

PubMed2001

[Detection of methylation status of p16 tumor suppressor gene in soft tissue leiomyosarcoma].

OBJECTIVE: To observe the methylation status of p16 tumor suppressor gene in human soft tissue leiomyosarcoma (LMS) and its relationship with p16 protein expression. METHODS: Methylation-specific PCR (MSP) assay was used to analyze the methylation status of 5' CpG island promoter/exon I region of p16 tumor suppressor gene in 38 LMS, 10 leiomyomas and 5 normal smooth muscle tissues. p16 expression in these tissues were examined by immunohistochemical assay. RESULTS: Hypermethylation of p16 was observed in 23.7% (9/38) of cases, of which 7 with negative pl6 staining and 2 with faint positive staining. In the cases without protein expression, hypermethylation rate of p16 was 50% (7/14). CONCLUSIONS: Epigenetic change due to 5' CpG methylation is the main cause of inactivation of p16 (INK4) gene which may be involved in tumor pathogenesis.

CpG Islands↗

PubMed2001

[Introduction to health education institutions in China in the first half of 20th century].

The "School Hygienic Committee" established in 1929 by coordinated work of ministry of Health and Education was the earliest health education institution, promoting school hygiene education. In the same year, the "Project of School hygiene" and "Project of Health Education" were issued which were the important regulations for hygienic education in which the requirements for hygienic education unit pushed the setting up of provincial or county hygienic education committee. Based on materials from over 20 provinces and cities, about a half of the units were named health education committee, the others were called hygienic education committee, mostly attached to the Bureau of Education with its tasks aiming at students. In a few provinces and cities, health education were listed in their working program.

China↗

PubMed2001

[Mechanotransduction in bone].

This article reviewed the progresses in the research of mechanisms of bone adaptation. The process of mechanotransduction can be divided into four distinct steps: mechanocoupling; biochemical coupling; transmission of signal; effector cell response. Through these four steps, the loads acting on the bones are transduced into biochemical signals, and then change the function of bone cells, finally induce the changes of bone structures to adapt the mechanical environment.

Adaptation, Physiological↗

PubMed2001

[Study on applicability of hepatitis C virus serotyping].

BACKGROUND: To explore the applicability of HCV serotyping. METHODS: Enzyme immunoassay (EIA) was used to detect the serotypes of 148 patients with viral hepatitis C. RESULTS: 56.08%(83/148) patients were serotyped,of whom 50.06%(42/83) were identified to be serotype 1,43.37%(36/83) serotype 2, and 6.03%(5/83)mixed serotype 1 and 2. The sera from 70 HCV RNA-positive patients out of the 83 ones who were successfully serotyped were detected for genotyping. The results were completely consistent between serotyping and genotyping. CONCLUSIONS: Serotyping of HCV has its clinical applicable value.

Genotype↗

PubMed2001

[Validation and comparison of ISO standard method for the examination of fluoride in drinking water].

The validation of ISO standard method for the examination of fluoride in drinking water was introduced. The test for compensating interference, standard curves, accuracy, precision and the minimum detection limit etc were included. The comparison between ISO method and others was made. The results indicated that the ISO method was better in anti-interference, wider linear range and higher precision. The points designed were reasonable. The method is superior to other methods in the same kind, and it should be adopted and extended.

Fluorides↗

PubMed2001

[Inhibitory effect of antisense c-myb cDNA on the growth of asynchronous glioma cells in vivo].

OBJECTIVE: To examine the therapeutic effect of oncogene c-myb antisense oligodeoxynucleotide (AON) on rat C6 glioma in vivo. METHODS: C6 glioma cells were implanted into the subcutis of nude mice, the animals were randomly divided into three groups (12 mice respectively) when the tumor grew about 10 mm in size, and the mice with subcutaneous tumor foci were treated with sense oligodeoxynucleotide (SON), AON and normal saline. Three animals of each group were killed after treatment at 4, 8, 12 and 16 days respectively. The dynamic growth manifestations, features, histopathological changes and apoptosis of the glioma in each group were observed. RESULTS: AON suppressed the growth of C6 glioma cells, the suppression rates being 66.7%, 71.4%, 72% and 73% at 4, 8, 12, 16 days respectively (P < 0.05). The changes in weight were concurrent with the variations of tumor volume, the tumor weight of AON groups was significantly decreased (P < 0.05). The immunohistochemical assay showed the expression of c-myb proto-oncogenes was significantly decreased in AON groups (P < 0.05). The flow cytometry analysis found the apoptosis cell percentage of AON groups to be 13.4%, 27.1%, 46.1% and 48.4% at 4, 8, 12 and 16 days respectively, and this percentage of AON groups was about 3.5 times the apoptosis cell percentage of SON and control groups at the corresponding time. In addition, noticeable inflammatory infiltration and calcification were observed after the treatment with AON. CONCLUSION: The above findings indicate that c-myb gene might be associated with the suppression of carcinogenesis in brain glioma, and oncogene c-myb might be chosen as a target for antisense gene therapy of gliomas.

Animals↗

PubMed2001

[The prognostic value of vascular endothelial growth factor in breast cancer].

OBJECTIVE: To define the relevance of VEGF status to the prognosis of breast cancer. METHODS: The tissues of 70 invasive ductal breast carcinomas were evaluated for VEGF protein expression by immunohistochemistry LSAB method, and the prognostic value of VEGF status was assessed in combination with the follow-up data on those breast cancer patients. RESULTS: VEGF status was inversely correlated with relapse-free survival and overall survival. Kaplan-Merier survival curve showed that VEGF-rich tumor group had higher relapse rate and mortality rate. Multivariate regression analysis confirmed that the VEGF status had certain prognostic value, but it could not be considered as an independent prognostic indicator. CONCLUSION: VEGF status is one of the significant prognostic indicators of breast cancer.

Biomarkers, Tumor↗

PubMed2001

[Clinical comparison between intraoperative local arterial infusion chemotherapy and systemic venous chemotherapy of gastric cancer].

OBJECTIVE: To evaluate the effect of intraoperative local arterial infusion chemotherapy for gastric cancer. METHODS: The effects of intraoperative local arterial infusion chemotherapy in 40 patients with gastric cancer were assessed. Twenty-four patients with gastric cancers who underwent the intraoperative systemic chemotherapy were taken as controls. The removed specimens were examined microscopically to show the degeneration and necrosis of the tumour cell. RESULTS: After the treatment of the tumour cells, all of the cases in the study group showed various degrees of degeneration and necrosis. The immediate effective rate was 95% for the the study group but only 41.67% for the control group (P < 0.05). CONCLUSION: Intraoperative local arterial infusion chemotherapy for gastric cancer has good immediate effect and little side effect; it prevents the intraoperative iatrogenic metastases and implantation and decreases the postoperative recurrence of gastric cancer.

Adenocarcinoma↗

PubMed2001

[Expression of KDR in medulloblastoma and its clinical implication].

OBJECTIVE: To gain an insight into the possible relationship between the expression of kinase insert domain-containning receptor (KDR) and the prognosis of medulloblastoma. METHODS: Fifty cases of medulloblastoma of the posterior fossa and ten cases of normal cerebellar tissue were studied via a combination of immunnohistochemical staining in formalin fixed paraffin-embedded sections. RESULTS: KDR was expressed weakly in 1 of 10 normal cerebellar tissues, while KDR was either moderately or strongly expressed in most of the medulloblastomas (49 of 50 cases). Moreover, KDR was expressed not only in the endothelial cells of tumor vasculature, but also in tumor cells. Correlation analysis indicated that expression of KDR was correlated significantly with survival time (r = -0.527, P < 0.01). CONCLUSION: KDR was expressed in most of the medulloblastomas, not only in the endothelial cells of tumor vasculature, but also in tumor cells. The expression level of KDR had a negative correlation with the survival time, thus it might be used as one of the prognosticators of medulloblastoma.

Adolescent↗

PubMed2001

[Expression and significance of urokinase-type plasminogen activator in medulloblastoma].

OBJECTIVE: To detect the expression and evaluate the clinical significance of urokinase-type plasminogen activator (uPA) in medulloblastoma. METHODS: LSAB (labelled streptavidin biotin method) immunohistochemical technique was applied for detecting the expression of uPA in 50 patients with medulloblastoma, and a follow-up survey with Cox regression analysis was made. RESULTS: The staining for uPA was localized on tumor cells and endothelial cells. Cox regression analysis showed that uPA was an independent prognostic factor affecting survival and it had a negative correlation with the prognosis. CONCLUSION: uPA appears to be an independent marker for predicting the prognosis of medulloblastoma.

Adolescent↗

PubMed2001

[Study on the working noise in BYPC and the effects caused by working noise on the workers' vestibular and auditory function].

OBJECTIVE: In order to observe the kinds and intensity of the working noise of Yansan Petrochemical Co. and the effects caused by the working noise on the workers' vestibular and auditory function. METHOD: The intensity and frequency of the working noise were recorded by exactolnoisemeter in the workshop. One hundred and seventeen workers were tested in routine pure-tone tested method. The SPVN and ABR were tested within fifty-one workers of all. RESULT: The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. The intensity of the working noise were during 85.7-104.0 dB(A) and the main frequency were during 1-8 kHz. About 59 percent workers who exposed to the working noise had hearing loss. The most hearing-loss were in the high frequency. The hearing-loss of speech frequency were slight. Workers who have more six years standing have obviously increased hearing-loss than the workers who have less five years standing. There were significant differences the ABR thresholds and wave-interval between the tested and controlled groups. The SPVN and CP were abnormal in more than 17.4 percent workers with hearing loss. CONCLUSION: The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. Working noise can lead to workers' hearing loss of certain degrees who exposed in the noise for a long time. Obvious correlation was not defined between the hearing-loss and the abnormal vestibular response group.

Adult↗

PubMed2001

[Separation of standard proteins and actual samples using cross-axis counter current chromatography].

A system of m (12.5% PEG8000): m (25% K2HPO4) = 1:1 was used to separate two kinds of standard proteins, glycoprotein in Morchella esculenta (L.) and glycoprotein in Lycium barbarum (L.), the upper phase was used as stationary phase, and the lower phase was used as mobile phase. The revolution speed was 500 r/min and the flow rate was 60 mL/h. In comparing with high performance liquid chromatography, cross-axis counter current chromatography can increase load capacity without loss of resolution. The advantage of this method was verified, indicating that cross-axis counter current chromatography was a useful method for biopolymer separation.

Ascomycota↗

PubMed2001

[Primary restoration for congenital malformation of external and middle ear].

OBJECTIVE: To promote the hearing, improve the appearance, shorten the therapeutic course in congenital malformation of external and middle ear, the program of primary restoration has been designed. METHOD: Under general or local anaesthesia a Z-shaped incision is made in skin. After turn up the flap A (defective ear) and flap B(retroauricular skin), a periosteal flap C with pedicle in front is made and elevated from mastoid. Then made frameworklize on mastoid and perform tympanoplasty. Once the myringograft is put properly the flap C is turn into the mastoidal cavity to serve as the lining of anterior wall. Flap A is sutured with the edge of retroauricular incision to serve as the lower part of new auricle. Then use the flap B to wrap a siliceous frame to make the upper part of new auricle. Finally, the naked walls of mastoidal cavity are lined with free skin graft and the cavity is packed with vaseline gauze for two weeks. RESULT: Two cases of congenital malformation of external and middle ear were treated with the procedure mentioned above and were followed up for one and 3 years respectively. Both effects of shape and hearing were good. CONCLUSION: The primary restoration for congenital malformation of external and middle ear designed by the authors is an excellent method worthy to be recommended.

Adolescent↗

PubMed2001

[Research of drug resistance and detection of methicillin-resistant Staphylococcus aureus in chronic maxillary sinusitis].

OBJECTIVE: To investigate the detection method of methicillin-resistant staphylococcus aureus (MRSA) in chronic maxillary sinusitis and the situation of drug resistance to some common antibiotics. METHOD: Using multiplex polymerase chain reaction technique to detect the drug resistant gene (mecA) of MRSA and specific gene (femA) of staphylococcus aureus at the same time. Drug resistant tests were performed with disk diffusion (K-B) method. RESULT: femA is a specific gene of staphylococcus aureus, the detective ratio of mecA in MRSA is 96.2% (51/53). Vancomycin is the only antibiotic which is sensitive to MRSA, while others are not. CONCLUSION: MRSA can be rapidly and specifically identified with multiplex PCR. There are drug resistance to many antibiotic drugs for MRSA.

Adolescent↗

PubMed2001

[Studies on characteristics of kinetics and metabolic shift of genetically engineered yeast Pichia pastoris in high-density chemostat cultivation].

Kinetics and metabolic shift of DNA recombinant yeast Pichia pastoris was studied in high-density chemostat cultivation in which the glycerol was used as a limited substrate. The experimental results showed that (1) cell optical density (OD600) of Pichia pastoris was linear with its dry cell weight (DCW) and wet cell weight (WCW), and reached 100 OD600 = 128.3 g WCW/L or 100 OD600 = 22.9 g DCW/L; (2) The relationship of specific growth rate (mu) and residual concentration of glycerol is accorded with Monod Equation, to obtain mu = mumax S/(Ks + S), where mumax = 0.366 h-1, Ks = 0.1823 g/L. The maximum cell yield of glycerol substrate YG = 0.54 g/g, growth maintaining coefficient m = 0.0069 g/(g.h), The cell yield of oxygen YX/O2 = 30.96 g/moL, and the optimum theoretical dilution rate Dm = 0.341 h-1 by parameter inference; (3) With specific growth rate (mu) increasing, glycerol metablic flux shifts linearly from glycogenesis and hexosephosphate pathways to glycolysis and tricarboxylic acid cycle pathways on basis of variations of consumption rate of NH3.H2O and respiratory quotient value.

Biotechnology↗

PubMed2001

[Inhibition the growth of human leukemia cells by Lycium barbarum polysaccharide].

The effect and the mechanism of Lycium barbarum polysaccharide (LBP-X) on inhibiting the growth of human leukemia HL-60 cells were examined. LBP-X(20, 100, 500, 1000 mg/L) could inhibit the growth of HL-60 cells in dose-dependent manner and decrease the membrane fluidity of the cell. Agarose gel electrophoresis of DNA from the cells treated with LBP-X revealed a "DNA ladder" and positive TUNEL test. The results showed that the apoptosis of HL-60 cells induced by LBP-X maybe its important mechanism on anti-tumorgenesis.

Antineoplastic Agents, Phytogenic↗

PubMed2001

[Investigation on genotype constitution of different Plasmodium vivax isolates and its geographical distribution in China].

OBJECTIVE: To investigate the population constitution and geographical distribution of Plasmodium vivax in China using molecular technique. METHODS: Blood-spot filter paper samples with related epidemiological data were collected from vivax malaria patients living in malarious area of 10 provinces (autonomous region) in China. Semi-nested- or nested-allelic-specific PCR genotyping method was used to identify CSP genotypes, families and types of Plasmodium vivax of each isolate from these patients. RESULTS: Of 384 field isolates of Plasmodium vivax, 258 temperate zone family strains were identified, including 14 allelic variant genotypes spreading among 10 sampling provinces; allelic variants sized less than 731 bp were only seen in 5 provinces in southern China; 79 tropical zone family strains including 5 genotypes were also distributed in 5 provinces of southern China south to 25 degrees N. lat; and 14 PV Type-2 strains including 2 genotypes were found in some areas of Hainan and Yunnan Provinces. In addition, 33 isolates from genotype-mixed infections were revealed. CONCLUSION: At present, area north to 25 degrees N. lat. of the country is the sole area prevalent for Plasmodium vivax family strains of temperate zone; there is overlapping distribution of P. v. of temperate zone family and tropical zone family of this parasite in the southern China south to 25 degrees N. lat; where the most complex isolate constitution is in Yunnan and Hainan Provinces, and PV Type-2 strains have been found in some areas of the two provinces. Besides, there were 2 groups of genotype with distinct geographic distribution feature within the temperate zone family.

Animals↗

PubMed2001

[The effects of safflor yellow on microcirculation and hemorheology of acute blood stasis rats].

OBJECTIVE: To observe the effects of safflor yellow on microcirculation and hemorheology of acute blood stasis rats. METHODS: The acute blood stasis medel was made by i.p. adrenalin (0.07 ml/(kg.time) for 2 times and the stimulation of ice-water. RESULTS: Safflor could markedly improve the number of net dot in microcirculation, and eta b, eta p, eta f in hemorheology (P < 0.05). CONCLUSION: Safflor yellow played an important role on blood stasis of rats.

Animals↗