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Dian-yuan Zhou

Publications and source records attributed to Dian-yuan Zhou.

13 recordsLinked to original sources
PubMed2006

[Clinical classification of Peutz-Jeghers syndrome].

OBJECTIVE: To propose the clinical classification of Peutz-Jeghers syndrome (PJS). METHODS AND RESULTS: Retrospective analysis of 52 patients with PJS admitted in Nanfang Hospital from 1980 to 2003 was conducted. Twenty-four patients were found to have family history of PJS, who had a mean age of 19 years. In the PJS patients, the incidence of gastric polyps was 64.4%, colorectal polyps 76%, and small bowel polyps 95%. The number of polyps was above 50 in 19 of the 31 patients with gastric polyps, in 18 of the 38 patients with colorectal polyps, and in 8 of the 19 patients with small bowel polyps. The pathology of the majority of the polyps (63/108) was characterized by hamartomas, and the incidence of malignancy was 13.5% in the PJS patients. CONCLUSIONS: PJS can be classified according to family history and location, pathology, and number of the polyps. As most patients with over 50 polyps require surgical intervention, 50 polyps is recommended as the criteria for PJS classification. Endoscopic surgery may suffice for management of patients with fewer polyps (<50), while in patients with more polyps or small bowel polyps, open surgery combined with intraoperative endoscopic surgery is recommended.

Adolescent↗
PubMed2006

[Clinical value of monitoring CD14+ monocyte human leukocyte antigen (locus) DR levels in the early stage of sepsis].

OBJECTIVE: To explore the relationship of monitoring CD14(+) monocyte human leucocyte antigen (locus) DR (HLA-DR) and the outcome in the early stage of sepsis. METHODS: Thirty-six definitely diagnosed septic patients in intensive care unit (ICU) were included. CD14(+) monocyte HLA-DR levels were detected by flow cytometer on the first day of the study, and acute physiology and chronic health evaluation II (APACHE II) scores were evaluated. Their clinical values in predicting the outcome of the disease were assessed through correlation analysis. RESULTS: Among 36 sepsis patients CD14(+) monocyte HLA-DR level<30% was found in 6 patients (16.67%). The average APACHE II score was 24.17+/-4.45 (r=0.212, P=0.687), all of them die, CD14(+) monocyte HLA-DR level <40% was 27.78% (10/36), the scores of APACHE II score was 23.50+/-4.30 (r=-0.0251, P=0.484), and the mortality rate was 80% (8/10). CONCLUSION: CD14(+) monocyte HLA-DR level <30% is an immunosuppressive index. In predicting the outcome of sepsis, it might be better than APACHE II scores. Immunosuppression is primarily found in the early stage of sepsis, suggesting that the classical compensatory anti-inflammatory response syndrome (CARS) hypothesis needs to be revised and improved.

APACHE↗
PubMed2005

[Preparation oral liposome-encapsulated recombinant Helicobacter pylori heat shock protein 60 vaccine for prevention of Hp infection].

OBJECTIVE: To prepare oral liposome-encapsulated recombinant Helicobacter pylori (Hp) heat shock protein 60 (Hsp60) vaccine and investigate its effect against Hp infection in mice. METHODS: The recombinant vector PET-22(+)/Hsp60 was transformed into BL21(DE3) E.coli. The recombinant protein was purified with Ni-NTA agrose resin and the oral liposome-encapsulated vaccine was prepared with phosphatidyl choline and cholesterols using film method, with the size distribution of the folate liposomes measured by transmission electronic microscopy. BALB/c mice were divided into 5 groups and immunized by intragastric administration of PBS, liposome, rHsp60 plus choleratoxin (CT), liposome-encapsulated rHsp60, and liposome-encapsulated rHsp60 plus CT, respectively, given once a week for 4 weeks. All the mice were challenged by Hp for 3 times within two weeks following the last immunization and sacrificed 3 weeks after the last challenge. Hp detection was performed by fast urease test. Semi-quantitative assessment of the bacterial colonization density observation of the inflammation severity and gastric histopathology were carried out. RESULTS: The soluble expression product accounted for 27% of the total bacterial protein. The purity of recombinant fusion protein was about 95% after purification. The mean size of the folate liposomes was 0.7+/-0.4 mum. PBS or liposome alone showed no immune-enhancing effect, and rHsp60 plus CT, liposome-encapsulated rHsp60 and liposome-encapsulated rHsp60 plus CT had the protective rates against Hp infection of 73.3%, 66.7% and 86.7%, respectively. The latter 3 preparations effected significantly reduced Hp infection and alleviated the inflammation in the gastric mucosa of the mice challenged with Hp. CONCLUSION: The oral liposome may serve as a potential adjuvant for Hp vaccine in preventing Hp infection.

Animals↗
PubMed2004

[Electron microscopic observation of primary cultured laterally spreading tumor cell line].

OBJECTIVE: To observe the microscopic characteristics of laterally spreading tumor (LST) cell line in primary culture. METHODS: The cells isolated from a rectum LST specimen obtained by endoscopic mucosal resection was primary cultured, followed by observation with scanning and transmission electron microscope in comparison with the cells of adenocarcinoma and normal mucosa of the rectum. RESULTS: Scanning and transmission electron microscopes both revealed numerous microvilli covering the surface of the LST cells, and the cytoplasm contained large quantity of lysosomes, mitochondria and phagosomes. Obviously heterogeneous cell nuclei were present with abnormal nuclear fossa and huge nucleoli. CONCLUSION: The cultured LST cells are highly malignant.

Adenocarcinoma↗
PubMed2004

[Preparation and characterization of monoclonal antibody against Clostridium difficile toxin A].

AIM: To prepare monoclonal antibodies (mAbs) against Clostridium difficile toxin A and identify their properties. METHODS: BALB/c mice were immunized with C.difficile toxin A. The splenocytes from immunized mice were fused with myeloma cells Sp2/0. The hybridoma cells were screened by indirect ELISA and limiting dilution method. The titer and relative affinity of ascitic mAbs were determined by ELISA. Specificity of mAbs was analyzed by Western blot. RESULTS: Six hybridoma cell lines (2H7, 3E9, 4B5, 5C10, 6G8 and 8A1) secreting mAbs against C.difficile toxin A were obtained. The Ig classes and subclasses of mAbs 2H7, 3E9 and 6G8 were IgM, mAbs 4B5 and 8A1 were IgG1, and mAb 5C10 was IgG2a. All 6 mAbs had no neutralization activity. Epitope recognized by 5 mAbs(2H7, 4B5, 5C10, 6G8 and 8A1) differed from that by mAb 3E9. Relative affinities of mAbs 8A1 and 4B5 were all above 10(5), and those of other 4 mAbs were 10(4). Western blot analysis no-denatured PAGE showed that all 6 mAbs reacted to C.difficile toxin A with M(r) being 55 x 10(4), and under the condition of denatured SDS-PAGE, Western blot analysis showed that all 6 mAbs reacted to subunits of C.difficile toxin A with M(r) being 5 x 10(4)-24 x 10(4). CONCLUSION: Six mAbs against C.difficile toxin A with high titers were obtained successfully with satisfactory specificity and relative affinity, which will be useful for detection of C.difficile toxin A.

Animals↗
PubMed2003

[Cloning and immunogenicity of conservative region of adhesin gene of Helicobacter pylori].

OBJECTIVE: To construct a candidate strain of Helicobacter pylori (Hp) that expresses the proteins of the conservative region of 4 adhesins (BabA2, AlpA, AlpB, and HopZ) and study its immunogenicity. METHODS: The DNA of Hp was extracted. Primers were designed according to the C-terminal structural gene sequence (called CB) of AlpA. The CB gene was amplified by PCR and inserted into the prokaryotic expression vector pET-22b (+) and expressed in BL21 (DE3) strain of Escherichia coli. The product of expression, CB, was purified by affinity chromatography and identified by Western blot analysis. ELISA assay was used to measure the CB-specific antibody in the specimens of serum of 55 Hp infected patients. Rapid urease test (RUT) was used on biopsy specimens collected by gastroscopy as parallel control. RESULTS: A recombinant plasmid pET-22b (+)/CB was constructed with the conservative region of the 4 adhesins. DNA sequencing showed one open reading frame of 588 bp encoding a polypeptide of 195 amino acids. The recombinant CB (rCB) protein, with a molecular weight of 22.5KD, amounted to 29% of the total bacterial protein. The purity of purified rCB was 96%. Western blot analysis showed that the rCB protein could be specifically recognized by the serum from Hp infected patients. The kappa coefficient was 0.76 for evaluation by ELISA and RUT results. CONCLUSION: CB has the potential to be used as a vaccine against Hp infection.

Adhesins, Bacterial↗
PubMed2003

[Pit pattern and endoscopic mucosal resection in diagnosis and treatment of colorectal tumors].

OBJECTIVE: To explore the effective methods to diagnose and treat colorectal cancer in its early stage. METHODS: 1 205 patients were examined by colonoscopy and mucosa staining with indigocarmine. The pit patterns were observed with magnifying endoscope and stereomicroscope according to the Kudo classification. The pathological diagnoses of the lesions were compared with their pit patterns. Electrocoagulation resection was performed on the prominent lesions and endoscopic mucosal resection (EMR) or endoscopic partial mucosal resection (EPMR) was performed on the flat lesions. RESULTS: In the 282 patients 478 prominent and flat lesions were found. There were 16 cases of laterally spreading tumor (LST), including I case of pit pattern II, 6 of pit pattern IIIL, 8 of pit pattern IV, and 1 of pit pattern Va, with 2 cases of intramembrane cancer and 1 case of IIa + IIc lesions invading the superficial myometrium among them. EMR and EPMR were performed on 14 LST lesions, 22 IIa lesions, and 14 IIb lesions. CONCLUSION: The examination of pit pattern is very important in early diagnosis of colorectal cancer and differentiation tumorous from non-tumorous lesions. V type pit pattern is an indicator of colorectal cancer. EMR and EPMR are safe and effective for flat lesions.

Colonoscopy↗
PubMed2003

[Construction of the non-resistant attenuated Salmonella typhimurium strain expressing Helicobacter pylori catalase].

OBJECTIVE: To construct a non-resistant attenuated Salmonella typhimurium (S.typhimurium) strain capable of expressing Helicobacter pylori (Hp) catalase. METHODS: After PCR amplification, the gene fragment encoding Hp catalase was inserted into the expression vector pYA248 containing asd gene, and the recombinant vector was then introduced into the host S.typhimurium strain X4072 depleted of genes encoding adenylate cyclase (delta cya), cyclic adenosine monophosphate receptor protein (delta crp) and aspartate-beta-semialdehyde dehydrogenase (delta asd). Bridged enzyme-linked immunosorbent assay (ELISA) was employed to measure the antigenicity of the catalase expressed in the sonicate and culture supernatant. According to Meacock's method and with the assistance of the growth curve, the stability of the recombinant strain was evaluated. A half lethal oral dose test was conducted to evaluate the safety of recombinant strain. RESULTS: S.typhimurium X4072 (pYA248-CAT) with expected capacity was successfully constructed, and bridged ELISA demonstrated higher catalase levels in the culture supernatant than in the sonicate of the recombinant strain X4072 (pYA248-CAT). After the strain was passaged for 100 generations without selection pressure, all the randomly selected colony of the recombinant strain grew well with positive catalase antigenicity as identified by ELISA. The growth curve of the recombinant strain showed comparable growth status of the 2 strains X4072 (pYA248) and X4072 (pYA248-CAT). The survival rate of C57BL/6 mice was 100% 30 d after oral administration of 1.0x10(10) cfu X4072 (pYA248-CAT). CONCLUSION: Non-resistant S. typhimurium vaccine X4072 (pYA248- CAT) is constructed successfully, which is stable in vitro and safe as confirmed by animal experiment. This vaccine provides a new candidate for viable oral vaccine against Hp infection.

Administration, Oral↗
PubMed2003

[In vitro evaluation of the safety and biological activity of recombinant Helicobacter pylori blood group antigen-binding adhesin].

OBJECTIVE: To evaluate the safety and biological activity of recombinant Helicobacter pylori (Hp) blood group antigen- binding adhesin (rBabA ) in vitro so as to investigate the feasibility of using rBabA as a Hp vaccine. METHODS: ELISA was used to measure rBabA-specific antibody in the serum of Hp-infected patients, and the proliferation of T lymphocytes in response to rBabA was examined by MTT assay. T cell apoptosis induced by rBabA was detected by diphenylamine assay. The effect of rBabA on Hp binding into human gastric carcinoma cell line(MGC-803) was determined by light microscopy. RESULTS: rBabA did not induce T cell apoptosis in BabA antibody- negative patients and was capable of stimulating T cell proliferation in rBabA antibody-positive patients. In the serum samples from 38 Hp-infected patients, the rBabA antibody positivity rate was 18.4%. rBabA could partially inhibit the binding of Hp to gastric epithelial cells. Under light microscope, the adhesion of Hp to MGC-803 was significantly inhibited by rBabA in comparison with negative control with PBS pretreatment. CONCLUSION: rBabA proves to be a safe and immunogenic bacterial component of Hp, which stimulates humoral and cellular immunity and can be a hopeful antigen targeting at BabA2 gene-positive Hp strain for the development of Hp vaccine.

Adhesins, Bacterial↗
PubMed2003

[Effects of the antibacterial peptide cecropins from Chinese oak silkworm, Antheraea pernyi on 1, 2-dimethylhydrazine-induced colon carcinogenesis in rats].

OBJECTIVE: To gain insight into the putative anticancer effect of the antibacterial peptides, cecropins, from Chinese oak silkworm, Antheraea pernyi, on the cancer cells and 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis in rats. METHODS: Growth inhibitory effect of the cecropins on normal human gastric epithelial cell line (GES-1) and human colon adenocarcinoma cell line (LS-174T) was observed using a microculture tetrazolium (MTT) colorimetric methods. Male Wistar rats were divided into 4 groups. Group1 was given on a weekly basis cecropins from Antheraea pernyi (3,000 Ua/ml) by gavage at 2 doses of 10 ml/kg body weight and exposed to subcutaneous injection of DMH at the dose of 20 mg/kg body weight. Group 2 was received weekly DMH only. Group 3 was given the cecropins by gavage at the same dose as in group 1. Group 4 was weekly exposed to subcutaneous injection of EDTA (1 mmol/L). All treatments were completed in a course of 18 weeks and the experiment was finished at week 33. RESULTS: MTT assay showed selective cytotoxic activity of the cecropins against the human colon adenocarcinoma cells line. The viability of the cancer cells was about 54% and 100% for the normal cells. There was a significantly lower incidence of large intestinal tumors in rats gavaged with cecropins (65%, P<0.01), but the tumor burden (tumors/tumor-bearing animal) and tumor mass index were comparable between the groups (P>0.05). CONCLUSION: The cecropins possess effective anti-tumor activity with no cytotoxicity against normal eukaryotic cells, and impede the neoplastic process in murine large intestines.

1,2-Dimethylhydrazine↗
PubMed2003

[Regulation of Fas expression in gastric epithelium: one of the auto-immune mechanisms of Helicobacter pylori pathogenesis].

OBJECTIVE: To investigate the pathogenic mechanism of Helicobacter pylori (H.pylori)-mediated gastric epithelial cell damage. METHODS: Fas expressions in gastric epithelial cell lines and freshly isolated gastric epithelial cells with or without H.pylori infection were evaluated by flow cytometry. The modulation of Fas expression in gastric epithelial cells by H.pylori or by Th1 cytokines present in H.pylori-infected gastric mucosa was assessed in vitro. The function of Fas expressed by the gastric epithelial cells to induce cell apoptosis was determined by enzyme-linked immunosorbent assay (ELISA) after incubation of the cells with anti-Fas antibody. RESULTS: All of the three gastric epithelial cell lines, AGS, N87 and kato-III, expressed detectable Fas protein when examined by flow cytometry. The percentage of positive cells and the amount of Fas protein on cell surface were larger in freshly isolated gastric epithelial cells with H.pylori infection than in uninfected cells (P<0.05). H. pylori alone or in combination with Th1 cytokines (IFN-gamma and TNF-alpha) significantly increased the expression of Fas in gastric epithelial cell lines in vitro. After incubation with IgM anti-Fas mAb, Fas-bearing gastric epithelial cells underwent apoptosis, and this effect of Fas was enhanced by IFN-gamma. CONCLUSION: Th1 cells accumulated in the gastric mucosa during H.pylori infection is involved in the damage of gastric epithelium through the modulation of Fas/Fas ligand interaction.

Apoptosis↗