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Biomedical subjects

D Zhang

Publications and source records attributed to D Zhang.

At least 217 records · Page 12Linked to original sources
PubMed2000

A trial of ademetionine in the treatment of intrahepatic biliary stasis viral hepatitis.

OBJECTIVE: To observe the efficacy and safety of ademetionine in the treatment of viral hepatitis with intrahepatic biliary stasis. METHODS: In this series, 110 patients with viral hepatitis associated intrahepatic biliary stasis were randomly divided into Groups A and B. Patients in Group A received ademetionine for four weeks. Patients in Group B received potassium magnesium aspartate for four weeks. RESULTS: In Group A, at the end of treatment, the effective rate for skin pruritus in patients with cholestatic hepatitis was 86.67% (13/15), and the effective rate for skin pruritus and anorexia were 88.24% (15/17) and 82.35% (14/17), respectively in patients with chronic hepatitis combining intrahepatic cholestasis, which were significantly higher than that in Group B (P<0.05). STB, SCB, TBA, ALT and AST were lower in Group A than Group B (P<0.05). The decrease of ALP and the increase of albumin after treatment were more significant in Group A than in Group B (P<0.05). CONCLUSION: Ademetionine has better efficacy than potassium magnesium aspartate in the treatment of patients with cholestatic viral hepatitis.

Adolescent↗
PubMed2000

Hepatitis B virus X protein activates expression of IGF-IR and VEGF in hepatocellular carcinoma cells.

OBJECTIVE: The expression of insulin-like growth factor I receptor (IGF-IR) and the vascular endothelial growth factor (VEGF) in HepG(2) cells transfected with a hepatitis B virus X (HBx) expression vector was investigated in an attempt to study their possible relationship to the growth of HBx-induced hepatocellular carcinoma (HCC). METHODS: The eucaryotic expression vector of HBx gene was constructed and introduced into HepG(2) cells. The modified cell HepaG(2)-X was synchronized in a quiescent state by culture of serum deprivation. The IGF-IR and VEGF were analyzed by immunohistochemical and Western blot technique. RESULTS: The positive rate of IGF-IR expression was 84%A3% in the transfected HBx gene cells, 26%A4% in X(0) control cells. The positive rate of VEGF expressed x cells was 83%A5%, X(0) cells was 28%A6% (P<0.001). The level of IGF-IR and VEGF in serum-starved x modified cells was 1.5 times higher than that of synchronized X(0) modified cells. CONCLUSION: Since the IGF-IR is a very important growth factor in sustaining the tumor abnormal growth and the VEGF has a crucial role in inducting tumor angiogenesis, our findings indicate that HBx may play an important role in the processes of HCC by activating IGF-IR and VEGF gene expression.

Carcinoma, Hepatocellular↗
PubMed2000

Selecting anti-HBsAg fab phage antibodies from the phage antibody library.

OBJECTIVE: Selecting Fab phage antibodies to HBsAg from the phage antibody library. METHODS: The phages displaying antibody fragments were subjected to three rounds of panning with HBsAg coated in solid phase. RESULTS: The eluted phages were enriched nearly 80-fold, and the percentage of recombinant clones increased from 17% to 100% after the third round of panning. The HBsAg specific monoclonal antibodies were determined by ELISA. These antibodies combined specifically with HBsAg, but not with BSA and HAV antigens. CONCLUSION: Our work on constructing human immunoglobulin combinatorial library and selecting anti-HBsAg Fab phage antibodies would be beneficial to the further study on the production of soluble Fab antibodies.

Bacteriophages↗
PubMed2000

[Effects of hepatitis B virus X gene on apoptosis and the activity of telomerase in HepG(2) cells].

OBJECTIVE: To observe the effects of hepatitis B virus X gene on hepatic carcinoma. METHODS: The expression vectors of HBs gene and HBc gene (pCEP4-S and pCEP4-C) were transfected into HepG(2) cells by electroporation technique, and the cells, HepG(2) cells which contained the expression vectors of HBs (pCEP4-X) were recovered and cultured stably. The activity index of telomerase and the apoptosis rates in three cell lines were determined by PCR-ELISA and flow cytometry. RESULTS: The 39.50% of cells expressed HBx gene came into S-phase of cell cycle, and the activity index of telomerase was higher in the cell line (3.95 +/- 0.07) than in other cell lines and control (F=20.85, P<0.01; d'=2.15, P<0.05) after synchronized culture. Induced by antisense oligonucleotides against telomerase the apoptosis of cell line expressed HBx gene reduced (apoptosis rate: 1.75%). The activity of cells also reduced with the dose increase of the antisense oligonucleotides and it showed a dose-response relationship. CONCLUSION: The activity of HepG(2) cell can be increased and the cell apoptosis can be reduced by HBx gene. It may be another malignant process of hepatocytes.

Apoptosis↗
PubMed2000

[Resistance of Bcl-2 adenovirus vector to HepG(2) cell apoptosis induced by ethanol].

OBJECTIVE: To evaluate the role of Bcl-2 family proteins in hepatocytic apoptosis caused by ethanol. METHODS: We induced hepatocytic apoptosis in HepG(2) cells with ethanol and detected the apoptosis with TUNEL assay. Bcl-2, Bax, and Bak protein expression in the hepatocytes was determined by immunohistochemistry method. We also observed the expression of Bcl-2 protein in HepG(2) cells infected with Bcl-2 adenovirus vector and its protection against hepatocytic apoptosis caused by ethanol. RESULTS: No obvious cytotoxicity was noted in 0.2% and 1% ethanol treatment group, while it developed in 3% ethanol treatment group and accompanied by a marked expression of Bax, Bak proteins. CONCLUSION: The overexpression of Bax, Bak proteins may play a role in HepG(2) cell apoptosis induced by ethanol and can be blocked effectively by Bcl-2 adenovirus vector.

Adenoviridae↗
PubMed2000

[Effect of domestic glutathione on the alcoholic liver disease].

OBJECTIVE: To evaluate the effect and safety of domestic glutathione (GSH) on serum ALT, AST, SB levels in alcoholic liver disease (ALD) by multicenter, randomized and TAD controlled trial. METHODS: All the 110 patients with ALD enrolled had a history of drinking over 80g-120g daily for 5 years, and were randomized either into GSH (continuous infusion of 600g daily for 30d) or TAD (with the same dosage, course and route as GSH) group. The efficacy and safery were evaluated with clinical and biochemical (ALT, AST and GGT) parameters. RESULTS: After 8 weeks of treatment, the clinical signs were improved at a different degree in both groups. ALT, AST and SB showed no significant difference in the two groups (the efficacy rate of 93% vs 96%, P>0.05). CONCLUSION: The domestic GSH, with a good tolerance and safety, has a sound efficacy in the improvement of clinical signs and hepatic functions.

Adolescent↗
PubMed2000

Chlamydia trachomatis mouse pneumonitis lung infection in IL-18 and IL-12 knockout mice: IL-12 is dominant over IL-18 for protective immunity.

BACKGROUND: Interferon (IFN)-gamma is a key to protective immunity against a variety of intracellular bacterial infections, including Chlamydia trachomatis. Interleukin (IL)-18, a recently identified Th1 cytokine, together with IL-12 is a strong stimulator for IFN-gamma production. We investigated the relative roles of IL-18 and IL- 12 in protective immunity to C. trachomatis mouse pneumonitis (MoPn) infection using gene knockout (KO) and wild-type (WT) mice. MATERIALS AND METHODS: Mice were intranasally infected with C. trachomatis MoPn and protective immunity was assessed among groups of mice by daily body weight changes, lung growth of MoPn, and histopathological appearances at day 10 postinfection. The corresponding immune responses for each group of mice at the same postinfection time point were evaluated by measuring antigen-specific antibody isotype responses and cytokine profiles. RESULTS: Our results showed that IL-18 deficiency had little or no influence on clearance of MoPn from the lung, although KO mice exhibited slightly more severe inflammatory reactions in lung tissues, as well as reduced systemic and local IFN-gamma production, compared with WT mice. Results with IL-18 KO mice were in sharp contrast to those observed with IL-12 KO mice that showed substantially reduced clearance of MoPn from the lungs, substantial reductions of antigen-specific systemic and lung IFN-gamma production, decreased ratio of MoPn-specific immunoglobulin G (IgG)2a/IgG1, and severe pathological changes in the lung with extensive polymorphonuclear, instead of mononuclear, cell infiltration. Exogenous IL-12 or IL-18 was able to increase IFN-gamma production in IL-18 KO mice; whereas, only exogenous IL-12, but not IL-18, enhanced IFN-gamma production in IL-12 KO mice. Caspase-1 is the key protease for activation of IL-18 precursor into the bioactive form, and caspase-1 KO mice also displayed similar bacterial clearance and body weight loss to that in WT mice at early stages of MoPn infection. This further confirmed that IL-18 was not essential for host defense against chlamydia infection. CONCLUSIONS: These results suggest that IL-12, rather than IL-18, plays the dominant role in the development of protective immunity against chlamydia lung infection, although both cytokines are involved in the in vivo regulation of IFN-gamma production.

Animals↗
PubMed2000

Fas ligand expression and apoptosis in primary rat hepatocytes induced by lipopolysaccharide.

OBJECTIVE: To study hepatocyte apoptosis induced by lipopolysaccharide (LPS) directly and indirectly, and to elucidate the mechanisms of liver damage in endotoxemia. METHODS: Rat hepatocytes were isolated using collagenase perfusion, and cultured in RPMI 1640 medium. After 24h or 48 h of LPS treatment at various concentrations (1, 5, 10 mug/ml), membrane-bound Fas ligand (mFasL) expression in hepatocytes was determined by immunocytochemistry, and apoptosis was detected by TUNEL. In another set of experiments it was examined whether LPS-treated hepatocytes and its supernatants can stimulate apoptosis in LPS-untreated hepatocytes. RESULTS: LPS markedly stimulated mFasL expression and apoptosis in hepatocytes in a dose and time (24-48 h) dependent manner. In the co-culture system LPS-treated hepatocytes significantly induced LPS-untreated hepatocyte apoptosis. In contrast, there was no apoptotic cells observed in the supernatant stimulation system. CONCLUSION: LPS not only directly causes hepatocyte apoptosis, but also indirectly induces apoptosis of LPS-untreated hepatocytes by way of stimulating mFasL expression in hepatocytes.

Animals↗
PubMed2000

Construction of the recombinant retrovirus vector of HBV-S gene and it's expression in eukaryotic cells.

OBJECTIVE: To investigate the effectiveness of recombinant retrovirus vector in gene therapy. METHODS: The retroviral vector PLXSN-S was constructed and transferred into PA317 by means of electroporation, then HepG(2), P815, and EL4 cells were infected with the pseudovirus produced from PA317, which highly expressed HBsAg. HBsAg expression was tested by RT-PCR and ELISA. RESULTS: HBsAg was expressed variously in the eukaryotic cells mentioned above. HBsAg (A value) of the cell supernatants (48 h) were 0.92, 0.09, 0.47, respectively. CONCLUSION: The vector used in this study is an effective one to carry genes of interest to target cells and it may be useful in the test for gene therapy.

Cell Line↗
PubMed2000

[Research on the relationship between expression of VEGF and high altitude pulmonary edema].

OBJECTIVE: To investigate the relationship between the expression of VEGF and the incidence of high altitude pulmonary edema (HAPE) and the mechanism of high altitude acclimatization-adaptation. METHODS: Pulmonary artery endothelial cells (PAEC) of rat were cultured. The expression of VEGF in PAEC was detected using RT-PCR and ELISA. Rats were divided randomly into five groups by weight: control, acute hypoxia (exposed to a simulated 8,000 m altitude for 4 hours), and three intermittent hypoxia groups (exposed to a simulated 3,000 m or 5,000 m altitude for 2 weeks, 4 hours a day, then to a simulated 8,000 m altitude for 4 hours). VEGF in the lung was detected using immunohis to chemistry and slot hybridization, and the changes of pathology in the lung were observed. VEGF in the blood plasma of rats, in men who immigrated to high altitude at different times, and in those who suffered from high altitude pulmonary edema were measured using ELISA. RESULTS: The expression of VEGF in PAEC was increased under hypoxia condition (1% O2) (P < 0.01). In the blood plasma and lung of rats during hypoxia, levels of VEGF and VEGF mRNA were higher than that in the control group. VEGF in acute hypoxia group was increased significantly compared with that in the intermittent hypoxia groups. Leakage of fluid in the lung of rats was observed in the acute hypoxia group. The longer the rats acclimatized, the lower the level of VEGF expressed, and the less the fluid leaked in the lung. The same tendency could be seen in humans. The level of VEGF in patients with high altitude pulmonary edema pre-therapy was higher than that measured post-therapy. CONCLUSIONS: Hypoxia could stimulate the expression of VEGF, and the upregulated expression of VEGF is one of the most important factors of incidence of high altitude pulmonary edema.

Altitude Sickness↗
PubMed2000

[Microwave heating modulation of skin fibrosis in chronic extremity lymphedema].

OBJECTIVE: To observe the effects of microwave heating on skin fibrosis in chronic extremity lymphedema. METHODS: Skin specimens from 8 cases of chronic limb lymphedema were tested by in situ hybridization (ISH) combined with avidin-biotin peroxidase (ABC) immunohistochemistry for detection of TGF-beta, procollagen I, procollagen III mRNAs and corresponding peptides expressions. RESULTS: It was discovered that expressions of TGF-beta 1 peptide were located at the spinous and granular layer of the epidermal cells with a great amount of dermal collagen I, III formation in accordance with high expressions of TGF-beta, procollagen I, procollagen III mRNAs in the dermal and subcutaneous tissue fibroblasts. After microwave heating treatment, the epidermal expression of TGF-beta 1 and relative TGF-beta, procollagen I, procollagen III mRNAs expressions in dermal fibroblasts were greatly reduced. The smaller calibre of collagen fibers after microwave heating was also observed. CONCLUSIONS: It is indicated that fibrosis in lymphedema is resulted from overexpressions of relevant genes like TGF-beta and subsequent extracellular matrixes (ECM) syntheses and deposition. Microwave heating can reduce fibroblast expressions of TGF-beta, procollagen I, procollagen III mRNAs as well as TGF-beta peptide synthesis, inhibiting ECM syntheses and deposition and finally reverse the skin fibrosis process.

Adolescent↗
PubMed2000

[Contraception in early 20th century China].

Modern contraception began early this century. In 1922, Mrs. Sanger of America came to China. Her theories of contraception and methods became the classical basis cited by Chinese workers on contraception. The Modern Women published since 1922 was the first professional publication in China, carrying many articles written by Chinese scholars. Monographs and translation of foreign works were also published. An institute for contraception was also founded in 1930. The Chinese Medical Association officially recognized contraceptive work as one of the public health works, marking the contraception, once lead by sociologists, under the category of the professional medical works.

China↗
PubMed2000

[Spread of Chinese variolation art to the western world and its influence].

Smallpox inoculation or variolation is a great invention of medicine in ancient China. In this paper, we introduced the process of spread of smallpox inoculation technique from China to western world (mainly to England), and reviewed the royal experiment of smallpox inoculation on human being and its influence on the prevention of smallpox in western countries. The spread and practice of smallpox inoculation in western world was an important event in the history of intercommunication between eastern and western medicines, which is worth emphasizing and further studying.

China↗
PubMed2000

Neuroendocrine differentiation in ovarian mucinous tumors.

OBJECTIVE: To investigate the relationship between neuroendocrine differentiation in ovarian mucinous tumors and its genesis. METHODS: A morphologic study of seventy-three cases of ovarian mucinous tumors (32 benign, 20 borderline, 21 malignant) using immunohistochemical and immunohistochemical/histochemical double staining techniques. RESULTS: The study showed that in tumors of benign, borderline and malignant types, the incidence of chromogranin A (CgA) positive cells was 62.5%, 75%, 76% and that of 5-hydroxytryptamine (5-HT) positive cells was 31.3%, 40% and 39%, respectively. Neuroendocrine cells (NEC) were not evenly distributed in any tumor. In four cases of the benign tumors, the number of CgA positive cells was more than 30 percent, localizing between the glandular basement membrane and the mucinous epithelial cells, with many intermediate cells containing both CgA and periodic acid-schiff (PAS) positive granules. CONCLUSION: The occurrence of both neuroendocrine and exocrine granules within the same cell has been previously described as "intermediate" in pancreatic hyperplasia, pancreatic tumors and lung signet-ring cell carcinoids. This has not previously been observed in benign ovarian mucinous tumors. Finding both endocrine and exocrine granules within a single cell seems to indicate a histogenetic relationship between the ovarian endocrine and exocrine cells. The four cases of the benign tumors might be originated from a common stem cell, such as the so-called amphocrine cell. The relationship between these four tumors and neuroendocrine differentiation in ovarian mucinous tumors needs to be further clarified.

Adenocarcinoma, Mucinous↗
PubMed2000

Effect of anti-P-selectin monoclonal antibody on renal ischemia/reperfusion injury in rats.

OBJECTIVE: To explore the effect of anti-P-selectin monoclonal antibody (mAb) on renal ischemia/reperfusion (I/R) injury in rats. METHODS: Renal function, renal histopathological changes, plasma P-selectin levels and renal P-selectin protein and mRNA expression were studied in a renal I/R injury rat models. Biochemical measurement, ELISA, Immunohistochemistry and Nested RT-PCR were used. RESULTS: Renal function insufficiency and renal histopathological damage were much less in the anti-P-selectin mAb-treated group than the saline-treated group. Plasma P-selectin levels were lower and renal P-selectin protein and mRNA expression were down-regulated in the former group. CONCLUSION: Anti-P-selectin mAb might be an efficient approach for the treatment of renal I/R injury.

Animals↗
PubMed2000

Detection of hepatitis B virus polymerase variations resistant to lamivudine therapy.

OBJECTIVE: To investigate variations in hepatitis B virus (HBV) polymerase gene in chronic HBV infected patients resistant to lamivudine therapy. METHODS: Specimens were obtained from nine patients with chronic HBV infection, who were resistant to lamivudine therapy. Partial segments of the HBV DNA polymerase gene were amplified by polymerase chain reaction (PCR). Nucleotide sequence was performed using an applied 373 automated sequencer. Titre of HBV DNA was measured by branched-DNA assay (Chiron). RESULTS: Of nine patients with HBV DNA positive after 64 weeks of treatment, five (56%) had variations in the highly conserved YMDD motif in domain C of the HBV polymerase, three of those were substitutions of isoleucine for methionine (M), and two were substitutions of valine(V) for methionine. Additionally, in two patients with variations characterized by substitutions of V for M, one had a simultaneous amino acid change from the first aspartic acid to glycine and this pattern of variation was not reported in other literatures. With respect to virernia, in two subjects with low titre of HBV DNA (< 100 MEq/ml), no variation was found in the YMDD motif, whereas in seven patients with high titre of HBV DBA (> 300 MEq/ml), five (71%) had variations in the YMDD motif. CONCLUSIONS: Lamivudine is a potent anti-viral agent for treatment of chronic HBV infection. Resistance to lamivudine is likely caused by the variations in the YMDD motif of the HBV polymerase gene.

Antiviral Agents↗
PubMed2000

[Correlation study of the longest diameter of gastric cardia cancer and its prognosis].

OBJECTIVE: Based on the longest diameter of cancer of gastric cardia, to formulate a new way of staging for better assessment of prognosis. METHODS: A total of 1,536 cases of resected carcinoma of the gastric cardia through left thoracic approach was statistically analyzed using STATA 5.0 software. The survival rate was estimated using life table method. The difference in survival rate between groups was evaluated by the log-rank test. The ratio difference between groups was evaluated by chi 2 test. RESULTS: The longest tumor diameter was divided into 6 grades according to its length: grade I, < 2 cm; grade II, 2 cm-< 4 cm; grade III, 4 cm-< 6 cm; grade IV, 6 cm-< 8 cm; grade V, 8 cm-< 11 cm and grade VI, > or = 11 cm. The 5-year survival rate was 61.5% in grade I, 44.4% in grade II, 26.4% in grade III, 20.5% in grade IV, 16.1% in grade V and 5.7% in grade VI, respectively. There was statistically significant difference (P < 0.05) in 5-year survival rate between 2 grades from grade II to grade VI. CONCLUSION: The longest tumor diameter is of prognostic significance in cancer of gastric cardia.

Adult↗