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Biomedical subjects

Y Zhou

Publications and source records attributed to Y Zhou.

At least 217 records · Page 12Linked to original sources
PubMed2001

[Study on new techniques for genetic diagnosis of deletional alpha-thalassemia].

OBJECTIVE: To develop polymerase chain reaction (PCR) techniques for diagnosis of three commonest deletional alpha-thalassemia determinants in China: - -(SA), - alpha(3.7) and - alpha(4.2). METHOD: Three groups of primers were designed and used to amplify the respective type of the deletional alpha-thalassemia under an optimized PCR condition, followed by agarose gel electrophoresis and EB-stainning. RESULT: Homozygous and heterozygotes, as well as double heterozygous of the 3 commonest deletions were successfully detected and diagnosed by the developed techniques. The results were identical to that from Southern Blot analysis. Forty two cases of alpha-thalassemia were diagnosed by these techniques. CONCLUSION: The 3 PCR-based techniques established by our lab were accurate, simple, and well reproducible for gene diagnosis of the deletional alpha-thalassemia determinants.

DNA Primers↗
PubMed2001

[Progress in telomerase and the inhibitors].

In cells division chromosome length is shorten for the ending DNA couldn't be replicated completely, and the loss of telomere DNA will lead to senescence and death. Activation of telomerase can elongate telomere length and maintain gene stability. Up-regulation of telomerase is considered to be responsible for immortalization and carcinogenesis. It plays an important role in cell-span and cell division. The telomerase inhibitors will become efficient drugs in tumor therapy.

Animals↗
PubMed2001

[The antioxidative effect of procyanidins from pine bark in vitro].

OBJECTIVE: To assess the antioxidative effect of procyanidins from pine bark on free radical damage. METHODS: Hemolysis, Malonaldehyde(MDA) level of mice liver homogenates, the conformation changes of irradiated plasmid PUC18 were used as indexes. RESULTS: Procyanidins could reduce the hemolysis degree of human RBC induced by H2O2 significantly(P < 0.01), reduce the MDA level of mice liver homogenate initiated by VitC/Fe2+ remarkably(P < 0.01), and reduce the degree of single-strain break of plamid PUC18 induced by 60Co gamma significantly(P < 0.01). CONCLUSION: Procyanidins had good antioxidative function. It can prevent RBC membrane, plasmid DNA suffering from oxygen free radical damage in vitro.

Animals↗
PubMed2001

[Diagnostic significance of measurement of the receptor for urokinase-type plasminogen activator on granulocytes and in plasma from patients with paroxysmal nocturnal hemoglobinuria].

OBJECTIVE: To investigate the expression levels of the receptor for urokinase-type plasminogen activator (uPAR) on granulocytes and the soluble uPAR (suPAR) level in plasma from patients with paroxysmal nocturnal hemoglobinuria (PNH) and its clinical application in the diagnosis of this disorder. METHODS: Expression of uPAR, CD55 and CD59 was measured on granulocytes by using flow cytometry (FCM) and the level of suPAR in plasma by using immunoradiometric assay (IRMA) in 20 patients with PNH, 59 anemic patients with diagnoses other than PNH (18 with autoimmune hemolytic anemia, 6 with other hemolytic anemias, 26 with aplastic anemia and 9 with iron deficiency anemia) and 21 healthy individuals. RESULTS: In PNH patients, both the mean fluorescence intensity and percentage of positive fluorescence-activated granulocytes of uPAR, CD55 and CD59 were remarkably decreased, while in anemic patients with diagnoses other than PNH the results were not different when compared with those of the healthy individuals. The expression level of uPAR was reduced to the same extent as that of CD55 and CD59 on the PNH-affected granulocytes. In addition, some peak shape abnormalities (double peaks and/or peak tailing) in the histogram of fluorescence intensity were also found in PNH patients. The suPAR concentration of PNH plasma was (4.04 +/- 2.47) micrograms/L, being higher than that of the healthy individuals (1.73 +/- 0.96) micrograms/L (P < 0.01). And the percentage of positive fluorescence-activated granulocytes was inversely associated with the plasma suPAR level in PNH patients (r = -0.79, P < 0.01). CONCLUSION: It is suggested that measurement of expression level of uPAR on granulocytes with FCM and suPAR in plasma with IRMA would be alteanative specific techniques for the diagnosis of PNH.

Adolescent↗
PubMed2001

[Detection of TTV DNA in liver tissues of patients with non A-G hepatitis by in situ hybridization].

OBJECTIVE: To demonstrate the existence of TT virus(transfusion-transmitted virus, TTV) in liver tissues of patients with unknown etiology. METHODS: Paraffin-embedded liver tissues from 51 cases who were non A-E hepatitis serologically and immunohistochemically negative for HBsAg, HCV NS3 antigen and HGV NS5 antigen were tested by in situ hybridization with Dig TTV DNA probe. RESULTS: The total positive rate of TTV DNA was 27.5% (14/51). Among the different pathological types, the positive rates were 30.8% (4/13) in acute mild hepatitis, 12.5% (1/8) in acute fulminante hepatitis, 42.9% (3/7) in subacute fulminante hepatitis, 33.3% (2/6) in chronic hepatitis, 22.2% (2/9) in active liver cirrhosis, 25% (1/4) in chronic fulminante hepatitis and 25% (1/4) in primary liver carcinoma respectively. Hybridization signals were detected within the nuclei or cytoplasm of the hepatocyte and most of them in nuclei. The positive cells were diffusely scattered in the intralobular areas in acute hepatitis and aggregated in periportal areas in chronic hepatitis or in the form of clustering in pseudolobules in active liver cirrhosis. CONCLUSION: Our results suggest that the TTV detected from liver tissues or sera from patients with unknown etiology is a novel virus, which belongs to hepadnavirus.

Adolescent↗
PubMed2001

[Effects of insulin and transforming growth factor-beta on alkaline phosphatase activity and total protein content in human periodontal ligament cells].

OBJECTIVE: The aim of this study is to evaluate the biological effects of insulin and/or transforming growth factor (TGF-beta) on alkaline phosphatase (ALPase) activity and protein synthesis of periodontal ligament (PDL) cells in vitro. METHODS: The fifth passage of PDL cells were cultured in a 5% humid CO2 environment at 37 degrees C by using Dulbecco minimum essential medium (DMEM) supplemented with 10% fetal bovine serum (FBS) for 24 hours, and then insulin, TGF-beta, and insulin and TGF-beta were added respectively in a medium of 1% FBS. After 5 days, their ALPase activities were measured by using a kinetic method, and the total protein content was measured by using Coomassie brilliant blue staining. RESULTS: Both insulin and TGF-beta significantly increased the ALPase activity and the total protein content of PDL cells at the concentrations from 1.0 to 100 U/L, and of 0.1-100 micrograms/L. The most optimal concentrations of insulin and TGF-beta were respectively 10 U/L and 1 microgram/L. The synergistic effect of insulin (10 U/L) and TGF-beta (1 microgram/L) was observed (P < 0.01). CONCLUSION: The results suggest that insulin and/or TGF-beta may promote the differentiation and protein synthesis of PDL cells. The combination of them may be valuable in the regeneration of periodontal tissue.

Adolescent↗
PubMed2001

[Confirmation of patulous eustachian tube syndrome by Tubo-tymanoaerodynamic graphy].

OBJECTIVE: To compare the advantage of tympanogram, Morimitsu's method and Tubotymanoaerodynamic graphy (TTAG) in the confirmation of patulous eustachian tube syndrome. METHOD: Twenty ears with patulous eustachian tube syndrome diagnosed clinically were selected. The tympanogram, Morimitsu's method and TTAG were examined in these ears and the positive rate was estimated. RESULT: The confirmation of patulous eustachian tube syndrome by tympanogram, Morimitsu's method and TTAG was 5, 12 and 20 ears in 20 ears with patulous eustachian tube syndrome. The positive rate was 25%, 60% and 100% respectively. TTAG also was useful in following-up. CONCLUSION: TTAG is an important method for diagnosis and following-up in patulous eustachian tube syndrome.

Acoustic Impedance Tests↗
PubMed2001

[Human papillomavirus DNA test in nasal polypsis].

OBJECTIVE: To evaluate pathogenesis of nasal polypsis. METHOD: To detect HPV in 26 pathological samples of 13 cases by polymerase chain reaction(PCR). Ten cases of normal nasal mucous were used as control. RESULT: HPV-DNA was positive 12 cases(92.3%) in 13 cases of the first surgical operation by PCR. HPV-DNA was positive 5 cases (38.5%) in 13 cases of the second surgical operation by PCR. The most HPV type was HPV6. HPV-DNA was negative in 10 cases of control. CONCLUSION: The results showed that HPV plays an etiologic role in the development of nasal polypsis.

Adult↗
PubMed2001

[Detection of radiation-induced apoptosis in nasopharyngeal carcinoma].

OBJECTIVE: To investigate the pathological changes after radiotherapy and its clinical significance of nasopharyngeal carcinoma (NPC). METHOD: Paraffin-embedded tissue blocks obtained from 30 cases of NPC before and during radiotherapy were used in this study. Using terminal oxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) and HE staining, the spontaneous and radiation-induced apoptotic rate (AR) were examined, and the pathological changes of NPC tissues before and after radiotherapy were compared. RESULT: The AR of radiation-induced apoptosis was significant higher than that of spontaneous apoptosis, but the AR was decreasing and the differentiation of proliferatic tumor clonogehic cell getting better during radiotherapy of NPC. CONCLUSION: The process of apoptosis was accelerated and the differentiation of proliferative tumor clonogehic cell getting better during radiotherapy of NPC.

Adolescent↗
PubMed2001

[Characterization and phylogenetics of a new species of genus Methanobacterium].

A strain of methanogenic bacterium Px1 was isolated from an anaerobic digester in the department of environmental sciences, TsingHua University, which treated the wastewater from Beijing Beer Factory. The isolate is curved rod, light-yellow colony, uses only H2 + CO2 as the substrate for CH4 formation. On the basis of physiology, morphology, structural characteristics and phylogenetic analysis, it is turned out that strain Px1 is a new species of the genus Methanobacterium, the name Methanobacterium curvum sp. nov. is proposed.

DNA, Bacterial↗
PubMed2001

Phacoemulsification in patients with secondary glaucoma caused by uveitis.

PURPOSES: To evaluate the effect of phacoemulsification in the patients with uveitis, secondary glaucoma and complicated cataract. METHODS: Phacoemulsification and implantation of a foldable intraoucular len was performed in 12 patients(13 eyes) with uveitis, secondary glaucoma and complicated cataract. The complications, intraocular pressures (IOP), and visual acuity were observed postoperatively. RESULTS: No severe complication was found in the patients postoperatively or within the operation procedure. The visual acuity was improved after the operation (P < 0.05). The intraocular pressures and/or the number of antiglaucoma medications reduced in 3 months of the follow-up time. CONCLUSION: Phacoemulsification is the best way to treat the patients with secondary glaucoma and complicated cataract caused by uveitis.

Adult↗
PubMed2001

[Influence of cell cycle in human trabecular cells induced by dexamethsone].

PURPOSE: To investigate the influence of dexamethesone (Dex) on cell cycle in human trabecular cells(HTC). METHODS: The trabecular specimens from human eyes were cultured in vitro. Then the cultured cells were immersed in DMEM solution containing 10(-7) M dexamethesone for three, five and seven days. The cell cycle was detected by Flow Cycometry. RESULTS: The G2 phase of cell cycle in HTC increased when HTC were treated by Dex. The G2 phase was 2% in control group. For three, five and seven days treated by Dex, the G2 phase were 8%, 16.3 and 19.4%. CONCLUSION: The influence of cell cycle might be induced by Dex, it may be related with the pathogenesis of glucocorticoid induced glaucoma.

Cell Cycle↗
PubMed2001

[Smoking and alcohol consumption as risk factors of pulmonary tuberculosis in Chengdu: a matched case-control study].

OBJECTIVE: The aim of this study was to assess the relationship between personal behaviors (smoking and alcohol consumption) and contracting pulmonary tuberculosis. METHODS: 346 persons (173 cases and 173 controls) were selected from 12 communities of Chengdu area, all the cases were active TB patients (by WHO criteria) from March 1996 to March 1997. Controls were matched for age, sex and living district. Subjects were interviewed face to face by trained interviewers using questionnaires. RESULTS: The results of univariate analysis showed that active smoking (OR = 2.12, P = 0.006), passive smoking (OR = 1.55, P = 0.04), type of cigarettes (OR = 1.31, P = 0.005) and alcohol consumption (OR = 1.81, P = 0.008) were significantly associated with TB. Yet, multivariate logistic regression analysis did not find smoking or alcohol consumption being in independent association with TB, but it showed that persons who were smokers with the addition of alcohol consumption had a higher risk to contract TB (OR = 7.729, 95% C.I. = 1.5215-39.2634). Significant association was noted in the dose-response analysis (OR = 1.73, 95% C.I. = 1.300-2.3028). CONCLUSION: These data indicate that smoking alone or sole alcohol consumption bears no relationship with TB, but smoking plus alcohol abuse is probably a risk factor for pulmonary tuberculosis in Chengdu, and in this connection, a proposal of prospective study to further demonstrate this risk factor is warranted.

Adolescent↗
PubMed2001

[Expression of vascular endothelial growth factor and nm23 as prognostic factors in nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the prognostic significance of vascular endothelial growth factor (VEGF) and nm23 expression for patients with nasopharyngeal carcinoma(NPC). METHODS: From Jan. 1991 to Dec. 1995, 75 NPC patients treated in Department of Radiotherapy & Chemotherapy, Zhongnan Hospital of Wuhan University, with follow-up of more than 4 yrs, were selected to enter this study. Specimens of 75 NPC were studied by immunohistochemical staining for VEGF and nm23. The immunohistochemical data were correlated with development of locoregional failure, distant metastasis and survival. RESULTS: Positive expression of VEGF and negative expression of nm23 were found in 54.7% and 56% of NPC specimens. Positive expression of VEGF and negative expression of nm23 correlated with the development of distant metastasis (P = 0.0181; P = 0.0091) and shorter survival (P = 0.0136; P = 0.0207). No association was observed with locoregional failure. No association was observed between the expression of VEGF and the expression of nm23.Cox proportional hazard model was used to compare the various factors and found the VEGF and nm23 expression were significant prognostic factors for patients with NPC. CONCLUSION: The results of the study show that the VEGF and nm23 expression are significant prognostic factors for patients with NPC and indicate that expression of VEGF and nm23 may be useful in identifying patients who may benefit from systemic chemotherapy or other novel treatment strategies.

Adolescent↗
PubMed2001

[Characteristics on ultraviolet absorption spectrum from difference in temperature and electron transition types of compounds].

The paper states a measuring method about Ultraviolet absorption spectrum from difference in temperature (UVSDT). The UVSDT of chemical compounds have been obtained with UV-240 ultraviolet spectrophotometer. The results show that the characteristic of UVSDT is related to electronic transition type of molecule. The long wave side shifts to long wave, when difference in temperature (delta t) accretes, peak high increases, bathochromic shift augments for UVSDT of n-sigma* electron transition. The UVSDT of n-pi* electron transition has two peak (one positive peak and one negative peak), when delta t accretes, the positive peak up increases, the negative peak down increases. The UVSDT of pi-pi* electron transition become negative peak, when delta t accretes, the negative peak down increases, the location of peak not moves.

Acetone↗
PubMed2001

[Research report of common oral diseases of 800 old people in Jing'an District, Shanghai].

OBJECTIVE: To find out the condition of the oral health of the old people in Jing'an district, Shanghai and explore new measures for their oral health taken by the community. METHODS: The method employed by us involves visiting 800 old people aged from 60 to 74 to inspect their oral health, using indexes and standards with reference to the standards used at the 2nd national oral epidemiological survey. RESULTS: Of the 800 old people investigated, 80.15% suffered from dental caries, 66.24% from gingivitis, 32.38% from periodontitis, 88.13% from impaired teeth, 16.25% from missing teeth and 54.63% from wedge-shaped damages of teeth. CONCLUSION: The old people have a rather poor oral-health condition and lack a self oral health awareness. The investigation suggests that in our communal health service, propaganda and education for oral hygiene should be carried out to the old people in a planned and targeted manner, along with preventive and restoration treatments.

English Abstract↗
PubMed2001

[Cell differentiation and down regulation of nm23 gene expression in HL-60 cells induced by 1,25 dihydroxyvitamin D3].

OBJECTIVE: To investigate the differentiation induction effect of 1,25 dihydroxyvitamin D3 on leukemia cell line HL-60 and its mechanisms. METHODS: The changes of proliferation rate and differentiation in HL-60 cells treated with 1,25 dihydroxyvitamin D3 were observed by MTT test, surface marker analysis and NBT reduction reaction, the effects on cell cycle and nm23 gene expression by flow cytometry and RT-PCR. RESULTS: After exposing to 1,25 dihydroxyvitamin D3, the proliferation was inhibited and the cells were induced to differentiate towards more mature monocytes. During differentiation, HL-60 cells were arrested in G1 phase and the expression of nm23 gene was down regulated. CONCLUSION: 1,25 dihydroxyvitamin D3 could induce differentiation of HL-60 cells, this effect might be related to the down regulation of nm23 gene expression.

Calcitriol↗