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Biomedical subjects

W Zhu

Publications and source records attributed to W Zhu.

At least 145 records · Page 8Linked to original sources
PubMed2000

Dexamethasone differentially regulates expression of carboxylesterase genes in humans and rats.

Carboxylesterases play important roles in the metabolism of endogenous and foreign compounds, therefore, xenobiotic regulation of carboxylesterase gene expression has both physiological and pharmacological significance. We previously reported that liver microsomal esterase activity was significantly decreased in rats treated with dexamethasone accompanied by a decrease in immunoreactive proteins of rat hydrolase A, B, and C. The aim of this study was to determine whether the suppressed expression of these enzymes was linked to the change of the mRNA levels, and whether cultured hepatocytes responded similar to whole animals to this chemical. Northern blotting analyses demonstrated that the levels of the corresponding mRNA were markedly decreased in rats treated with dexamethasone, suggesting that the suppressed expression is achieved through trans-suppression and/or increased degradation of the transcripts. Exposure of cultured rat hepatocytes to nanomolar levels of dexamethasone markedly decreased the levels of immunoreactive proteins of hydrolase A, B, and C. In contrast, exposure of cultured human hepatocytes to dexamethasone caused a slight increase in HCE-1 and HCE-2, two major forms of human liver microsomal carboxylesterases. The inductive effects in human hepatocytes were observed only when micromolar concentrations of dexamethasone were used. These results suggest that a major species difference exists regarding the regulation of carboxylesterase gene expression by dexamethasone. Both the glucocorticoid receptor and the pregnane X receptor are known to mediate dexamethasone action. Differential concentrations required suggest that suppression of rat hydrolases is mediated by the glucocorticoid receptor, whereas the induction of human carboxylesterases is mediated by the pregnane X receptor.

Amino Acid Sequence↗
PubMed2000

[Bone marrow transplantation for beta-thalassemia major].

OBJECTIVE: To examine the feasibility of bone marrow hematopoietic stem cell transplantation for thalassemia major. METHODS: Bone marrow transplantation was performed on a 4-year-old patient with beta-thalassemia major, whose gene mutation was CD41-42/654. The donor was his brother. In the 850ml bone marrow, the nucleated cells were 5.6x10(8)/kg, CD(+)(34) cells 7.8 x 10(6)/kg, and colony-forming-unit-granulocyte-macrophages(CFU-GM) 5.7x10(5)/kg. HLA was one site mismatched, while RBC type matched. Pre-transplant conditions included Busulfan 16mg/kg, cyclophosphamide 200mg/kg and lymphoglobuline 88mg/kg. Cyclosporine and methotrexate were used for prevention of graft-versus-host disease(GVHD). RESULTS: After transplantation, the patient had grade II acute GVHD and cytomegalovirus(CMV) interstitial pneumonia; he was cured. White blood cells(WBC) and neutrophil granulocytes recovered to 1.1 x 10(9)/L and 0.4 x10(9)/L respectively on day 14 post transplantation. WBC was 4.5 x 10(9)/L on day 18, and descended for a time during treating interstitial pneumonia with Ganciclovir. Platelet(Plt) exceeded 50 x 10(9)/L on day 86 and recovered to normal 5 mothers and a half post transplantation. Hb reached 106g/L on day 128. The patient received the last blood transfusion on day 103. Before transplantation, the patient had to receive 200ml blood infusion per month for maintaining Hb 60-90g/L; after transplantation, his Hb kept up >110g/L for 6 months without blood transfusion. The gene type had changed to donor's CD41-42/N heterozygen. CONCLUSION: This is the first report on successful transplantation of bone marrow stem cell for thalassemia major in China, suggesting a new way to treat the disease and to expand the use of BMT. For treatment of CMV interstitial pneumonia post-transplantation, Ganciclovir should be dose enough and be used for at least 2 months.

Child, Preschool↗
PubMed2000

[Genotyping cytochrome P450IIE1 in alcoholic liver diseases and its significance].

OBJECTIVE: To study the relationship between genotypes of cytochrome P450IIE1 (IIE1 ) and development of chronic liver diseases. METHODS: Cytochrome P450IIE1 was genotyped by PCR and restricted endonucleases digestion of DNA prepared from peripheral white blood cells. RESULTS: IIE1 could be divided into three types: A, B and C based on different products digested by two endonucleases. In normal controls predominant genotypes were A and B. No relationship was found between development of non-alcoholic chronic liver diseases and IIE1 genotypes. Its genotype distribution was similar to normal controls. Detection of type A in alcoholic liver diseases was significantly decreased and type B was significantly increased (P<0.01). Detection of type A in alcohol-related hepatocellular carcinoma was also decreased and type B increased compared to non-alcohol-related hepatocellular carcinoma. CONCLUSION: IIE1 genotypes play some roles in development of alcoholic liver diseases and alcohol-related hepatocellular carcinoma.

Adult↗
PubMed2000

[Partial nucleotide sequences of hepatitis E viruses isolated from patients in 14 cities of China].

OBJECTIVE: To investigate the genotypes of hepatitis E viruses isolated in China. METHODS: The partial genome of open reading frame 2 (nt6461-6860, nt5994-6294) of 45 HEV isolated from patients in 14 cities of China was amplified and sequenced using polymerase chain reaction and direct sequencing. RESULTS: 41 of 45 isolates (91%) shared the same genotype with HEV Burma strain (B), with nucleotide identities higher than 98% with the representative HEV Chinese strain. Only 4 HEV isolates were significantly divergent from the 3 prototype strains of HEV, with nucleotide identities of 77%-80% with HEV Burmese/Chinese strain, 74%-76% with Mexico strain and 74%-77% with the newly discovered HEV US/Swine strain, respectively. Phylogenetic analysis suggested that these 4 isolates represented 2 different subtypes belonging to a novel genotype of HEV, which was significantly divergent from the prototype Mexican, Burmese and US/Swine isolates. CONCLUSION: Among patients with hepatitis E in China, most are infected with the Chinese prototype HEV, and only a small part with the new genotype HEV.

China↗
PubMed2000

[Influences of BN50739 on neutrophil elastase and phospholipase A2 in lung and tracheal mucosa of pigs with acute severe pancreatitis].

OBJECTIVE: To investigate the effects of platelet-activating factor (PAF) and a new potent PAF-receptor antagonist, BN50739, on the activities of neutrophil elastase and phospholipase A2 (PLA2) in lung and tracheal mucosa of pigs with acute severe pancreatitis (ASP) induced by sodium taurocholate. METHODS: There were twenty eight pigs weighing 16-22 kg, which were divided into five groups. Group I (n = 5): sham-control; Group II (n = 6): ASP-control; Group III (n = 5): DMSO-control; Group IV (n = 6) and Group V (n = 6): pre- and post-treatment with BN50739. Anesthesized pigs were subjected to ASP induced by injecting 1 ml/kg of combined solution of 5% sodium taurocholate and 8,000-10,000 BAEE units trypsin/ml into pancreas via pancreatic duct. All pigs were sacrificed by injecting 20 ml of 10% KCl intravenously. Specimens of lung and tracheal mucosa were removed, weighed and homogenized in grinding tubes. The homogenate was centrifuged and the supernatants were collected for the assays of NE, PLA2, MPO and PAF. RESULTS: The activities of NE, PLA2 and MPO and the levels of PAF in lung and tracheal mucosa increased significantly in ASP pigs. There are significantly positive relationships between PAF and NE, PLA2, MPO or W/D in lung and tracheal mucosa. The PAF levels in lung and tracheal mucosa and the severity of acute lung injury induced by PMN sequestration, NE and activated PLA2 reduced remarkably by the pre- and post-treatment with BN50739. CONCLUSIONS: PAF plays an important role in acute lung injury in porcine ASP, which may be associated with the increments of PMN sequestration, NE and the highly activated PLA2 in lung and tracheal mucosa. The pre- and post-treatment with BN50739 can effectively reduce the PAF levels in lung and tracheal mucosa and the severity of acute lung injury following ASP via reducing the PMN sequestration and the amount of elastase, and by inhibiting PLA2 activities in lung and tracheal mucosa.

Animals↗
PubMed2000

[Expression of Epstein-Barr virus latent membrane protein 2 in murine fibroblasts by retroviral-mediated gene transfer].

OBJECTIVE: This study is to find an efficient way to express EB virus latent membrane protein 2 in mammalian cells, and provide for further investigate on the function of LMP2 protein and its role in cellular immunity. METHODS: The LMP2 gene was cloned into the EcoR I site of a retroviral vector LXSN and the recombinant LXSN-LMP2 was transfected into PT67 by lipofect TAMINE. After screened by G418, the supernatant of G418-resistant cells was used to infect murine fibroblasts NIH 3T3 to determine the virus titer. DNA was extracted from transfected cells and tested by PCR. Indirect immunofluorescence assay was used to detect the expression of the inserted gene. RESULTS: The virus titer was 5.8 x 10(5) PFU/ml. The result of PCR showed that the LMP2 gene had been integrated into the DNA of transfected cells. Indirect immunofluorescence showed that the LMP2 gene had been expressed in the murine fibroblasts. CONCLUSIONS: EB virus LMP2 gene had been integrated into the genome of cells by retroviral-mediated transfer and the target gene had been expressed.

3T3 Cells↗
PubMed2000

[Interaction of Se and S forms in rhizospheric soil and their absorption by tobacco].

Pot experiment with tobacco shows that the amount of total, solube, exchangeable and organic Se in rhizospheric soil appeared depletory, while that of total, adsorbed and organic S appeared enriched. The influence of added S on Se depletion depended on the level of Se application, and that of added Se on S enrichment depended on the rate of S applicagtion. In the absence of added Se, the addition of S decreased the depletion of several Se forms; while in its presence, the reverse result was obtained. The addition of Se increased the enrichment of total S when the S was not added. With S application, the added Se reduced the enrichment of total S. At early stage, teh Se content of tobacco was mainly influenced by the soluble Se in rhizospheric soil, while the accumulated amount of Se in tobacco was also influenced by exchangeable, organic and acid soluble Se. The S content in the aboveground part of tobacco at its early stage was mainly influenced by soluble and organic S in the rhizosphere.

Absorption↗
PubMed2000

Effects of platelet activating factor antagonist (BN50739) on gut mucosal injury in acute severe pancreatitis in pigs.

OBJECTIVE: To study the role of platelet activating factor (PAF) in the pathogenesis of intestinal mucosal injury and endotoxin/bacterial translocation in acute severe pancreatitis (ASP) in pigs. METHODS: ASP was induced by intraductal injection of a mixture of sodium taurocholate and trypsin. BN50739, a specific antagonist of PAF, was given 30 min prior to the induction of ASP. Mucosal blood flow, mucosal myeloperoxidase (MPO) and malondialdehyde (MDA) were determined. Intestinal injury was observed microscopically. Portal blood endotoxin levels and the bacterial counts in the portal blood, intestinal lymph nodes and the pancreas were determined. RESULTS: Prior antagonism of PAF by BN50739 reduced intestinal injury, increased intestinal mucosal blood flow, and reduced blood levels of endotoxin and bacterial counts in the portal blood, mesenteric lymph nodes and pancreas. CONCLUSIONS: Intestinal mucosal injury developed in ASP. PAF is responsible for the injury. Antagonism of PAF by BN50739 can improve intestinal microcirculation and reduce the severity of intestinal mucosal injury, which may decrease endotoxin/bacterial translocation.

Acute Disease↗
PubMed2000

99mTc-MIBI and 99mTc-MDP scintimammography for detecting breast carcinoma.

OBJECTIVE: To assess the value of scintimammography with both 99mTc-MIBI and 99mTc-MDP in detecting breast cancer. METHODS: A total of 35 women with clinical findings of suspicious breast lesions were studied with both 99mTc-MIBI and 99mTc-MDP scintimammography. All patients underwent surgery within one week and the final diagnostic results (histopathological) were obtained. RESULTS: Eighteen of 35 abnormalities of breast were pathologically confirmed as breast cancer and 17 as benigN lesions. In this group of patients studied, the sensitivity, specificity and accuracy of 99mTc-MIBI scintimammography were 77.8%, 88.2% and 82.9%, respectively and those of 99mTc-MDP scintimammography were 72.2%, 88.2% and 80.0%, respectively. There was no significant difference between 99mTc-MIBI and 99mTc-MDP scintimammography. CONCLUSION: This study showed the high diagnostic accuracy of both 99mTc-MIBI and 99mTc-MDP scintimammography in detecting breast cancer. Both can be used as non-invasively assess breast cancer invasiveness before surgery.

Adult↗
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

[Value of Gallium-67 scanning in differentiation of malignant and benign tumor in oral and maxillofacial area].

OBJECTIVE: To evaluate Gallium-67 scanning in differentiation of malignant and benign tumor in oral and maxillofacial region. METHODS: 41 patients with tumors in the oral and maxillofacial region were undergone Gallium-67 scanning. The results were correlated with the final pathologic diagnosis. RESULTS: Twenty out of 21 patients who had malignant tumors showed positive Gallium-67 scanning images (95.23%); three of 20 patients who had benign tumors also demonstrated positive results (15.00%). There was a significant difference between these two groups (P < 0.001). CONCLUSIONS: Gallium-67 scanning is a useful adjunct tool for differentiation of malignant and benign tumors in oral and maxillofacial region.

Adult↗
PubMed2000

[Etiological study on patients with seronegative viral hepatitis].

OBJECTIVE: To investigate the etiology of hepatitis patients who were seronegative for viral hepatitis A through E. METHODS: By using PCR, HBV DNA, HCV RNA, HEV RNA and HGV RNA were detected in sera of 104 patients with seronegative viral hepatitis. The partial nucleotide sequences of 2 HCV and 17 HEV isolates were analysed by direct sequencing. RESULTS: Among the 104 patients with seronegative viral hepatitis, the positive rates of HBV DNA, HCV RNA, HEV RNA and HGV RNA were 29.8%, 3.8%, 22.1% and 7.7%, respectively, with only 38 cases (36.6%) negative for the genome of all known hepatitis viruses. CONCLUSION: In addition to serological tests, the polymerase chain reaction of all known hepatitis viruses should be used to make the diagnosis of non-A - E hepatitis.

Base Sequence↗
PubMed2000

[Hematopoietic stem cell transplantation for beta-thalassemia major].

OBJECTIVE: To discuss the feasibility of hematopoietic stem cell transplantation for beta-thalassemia major. METHODS: Bone marrow or cord blood of sibling was transplanted to 4 children with thalassemia, whose type of gene mutations was homozygous. All of them were diagnosed as beta-thalassemia major. HLA type was matched in 2 cases, and mismatched with 1 locus in the other 2. RBC type was mismatched in 1 cases. Pretransplant condition including busulfan (BU) 16 mg/kg, cyclophosphamide (CY) 200 mg/kg and anti-thymocyte globulin (ATG) 90 mg/kg. Graft-versus-host disease (GVHD) prophylaxis was cyclosporine-A (Cs-A) and methotrexate (MTX). RESULTS: Two Children had "serum sickness" during pretransplant condition; two children had grade II acute GVHD and 1 developed chronic GVHD, 1 case veno-occlusive disease (VOD), 1 case cytomegalovirus (CMV) interstitial pneumonia and 1 case fungemia post-transplant, which had been cured. The average time for peripheral WBC recovery > 1.0 x 10(9)/L was 16 days, 18 days for neutrophile granulocyte > 0.5 x 10(9)/L, 59 days for Plt > 50 x 10(9)/L and 39 days for Hb > 100 g/L. The average time for WBC recovery to normal was at day 24. The average time of last blood transfusion for patients was 29 days. The patients had to receive about 100 ml blood infusion per 2 months pretransplant, while not infused for 7 approximately 15 months up to now with Hb > 100 g/L. Gene mutation type of patients had changed to donor's. CONCLUSION: We report a successful transplantation of bone marrow and cord blood stem cells for thalassemia major in China. This will give a new strategy for treatment of the disease and further expand the use of stem cells transplantation.

Child, Preschool↗
PubMed2000

[Adjustable interatrial communication in management of severe congenital heart disease].

OBJECTIVE: To assess the use of adjustable interatrial communication in patient with severe congenital heart disease undergoing open heart surgery. METHODS: From February 1998 to June 1999, 13 patients with severe and complex congenital heart disease underwent open heart surgery. Seven patients underwent total cavopulmonary connection, five patients repair of Ebstein's anomaly, and one patient right atrial-pulmonary connection. Adjustable interatrial communication was made in all patients. Four patients had the communication closed at the time of operation, 4 patients had the communication opened at the time of operation, and 5 patients had the communication adjusted and closed postoperatively. RESULTS: All patients had a smooth postoperative process. There were no postoperative death and no severe postoperative complications. CONCLUSION: Adjustable interatrial communication for the patients undergoing modified Fontan procedure or correction of Ebstein's anomaly may be advantageous.

Adolescent↗
PubMed2000

Rehabilitative therapy of short bowel syndrome: experimental study and clinical trial.

OBJECTIVES: To investigate the effect of growth hormone on proliferative activity of the residual small intestinal mucosa after massive small intestinal resection and to evaluate the clinical efficacy of bowel rehabilitative therapy for short bowel syndrome. METHODS: Small intestinal mucosa proliferative activity were compared in rats from control group (sham operation), short bowel group (80% small bowel resection) and growth hormone treatment group (80% small bowel resection + growth hormone 1 U x kg(-1) x d(-1) for 28 days) with the aid of histology image analysis, flow cytometric assay, immunohistochemistry analysis and RT-PCR assay. The nutritional status, D-xylose absorption and stool nitrogen output were observed in 9 consecutive parenteral nutrition dependent patients with short bowel syndrome after intestinal rehabilitative therapy (growth hormone 8 - 12 U x kg(-1) x d(-1) im + glutamine 0.6 g x kg(-1) x d(-1) iv + special diet) for 21 continuous days. RESULTS: Growth hormone administration significantly increased rat small intestinal mucosal villous height, mucosal thickness, proliferative index, and the expression of proliferating cell nuclear antigen and c-jun mRNA. Rehabilitative therapy increased the body weight, serum total protein and album in concentrations in patients. Their D-xylose absorption indices increased and fecal nitrogen losses decreased. Follow-up data showed that 6 of the 9 patients sustained on enteral nutrition. CONCLUSION: Growth hormone enhances the proliferative activity of the mucosal epithelium and bowel rehabilitative therapy may benefit the patients with short bowel syndrome.

Adolescent↗
PubMed2000

[Study on risk factors of breast cancer among urban women in China].

OBJECTIVE: Breast cancer is the most common malignant neoplasm in women all over the world. It is necessary to establish monitoring methods and to identify risk factors. METHODS: Six cities including Beijing, Shanghai, Tianjin, Chongqing, Wuhan and Guangzhou were chosen as the sample areas. 2 100 cases with 1:1 matched controls were interviewed with a uniformed questionnaire. Conditional logistic regression and cluster analysis were used for multivariate analysis. RESULTS: The common risk factors for the combined data of the six cities were high educational level (OR: 1.17), high body mass index (OR: 1.51), high intake of milk products (OR: 1.49), high intake of eggs (OR: 1.14), psychological depression (OR: 2.78), history of benign breast diseases (OR: 2.24), old age at marriage (OR: 1.42), dysmenorrhea (OR: 1.22), short duration of lactation (OR: 1.17). Among these factors, different cities had different ORs, as high educational level (OR: 1.20 - 1.61), high body mass index (OR: 1.40 - 22.36), high intake of milk products (OR: 1.64 - 3.39), depression (OR: 1.60 - 10.50), history of benign breast diseases (OR: 1.73 - 19.44). Some statistically significant correlations existed in different cities such as early age at menarche, old age at marriage, long menstrual periods, high intake of meat, eggs, sea food and passive smoking were risk factors. Some risk factors varied between premenopausal and postmenopausal women. Beijing, Wuhan and Chongqing were clustered as the same group in cluster analysis, so did Shanghai and Tianjin, but Guangzhou could not be grouped with other cities. CONCLUSION: Some common risk factors for breast cancer did exist in the six cities, but there were varieties in different areas which showed different places would have their own characteristics. Thus, careful study of risk factors, especially in the selection of variables and data analysis need to be carried on.

Breast Neoplasms↗
PubMed2000

[Effects of methylmercury on intracellular free calcium content in cerebral cortical neurons].

OBJECTIVE: This study was conducted to explore effects and potential mechanism of methylmercury on concentration of intracellular free calcium (Ca(2+)) in the acutely isolated cerebral cortical neurons. METHODS: Calcium ion indicator Fura-2 two wave-length fluorophotometry was used to measure concentration of Ca(2+). RESULTS: (0.10 - 5.00) x 10(-6) mol/L of methylmercury could increase level of free intracellular Ca(2+) in cerebral cortical neurons significantly (P < 0.01), in a dose-response manner. Increase in intracellular free Ca(2+) of neurons caused by methylmercury associated with large influx of Ca(2+) outside cells and release of stored Ca(2+) inside cells, especially by influx of Ca(2+) outside cells. Influx of Ca(2+) outside cells associated with Ca(2+) channels regulated by receptor gate and potential gate, but not associated with sodium-dependent channel. CONCLUSION: Methylmercury lead to abnormal increase of intracellular free Ca(2+) in neurons, which is closely related to Ca(2+) channel.

Animals↗