DNA Methylation ; Helicobacter Infections ; complications ; Helicobacter pylori ; Humans ; Stomach Neoplasms ; etiology ; genetics ; Telomerase ; physiology

Objective To investigate the molecular mechanism of Helicobacter pylori (H.pylori) resistance to clarithromycin. Methods The E test was used to determine clarithromycin resistant strains of H.pylori , and PCR Restriction Fragment Length Polymorphism (RFLP) analysis for 23S rRNA domain V gene mutations. Results Of nine clarithromycin resistant stains of H.pylori , including six primary and three acquired resistant strains, eight were found to have an A to G mutation in 23S rRNA domain V at position 2144. Conclusions The results indicated that the majority (88.8%) of clarithromycin resistant isolates of H.pylori in Shanghai have an A2144G mutation in 23S rRNA domain V.

Objective Atrophic gastritis, as a pre-cancerous condition of gastric cancer, is developed from non-atrophic gastritis.The aims of this study was to compare the gene expression profiles between atrophic gastritis and non-atrophic gastritis using cDNA microarray and to explore the molecular mechanisms in the development of atrophic gastritis. Methods Endoscopy and biopsy were performed consecutively in 227 patients (143 male, 84 female, age range between 16-72 years, with average age 48.6 years). Diagnosis of non-atrophic gastritis and atrophic gastritis was made according to histological examination, and 120 patients were in non-atrophic group and 107 in atrophic group. The total RNA was extracted from the biopsy specimens of two groups with Trizol reagent. cDNA microarray consisting 8 464 human genes (HGEC-80s kit) was used, and labeled cDNA with fluorescence probes were hybridized to microarray, and then the comparison of gene expression profiles was made between atrophic and non-atrophic gastritis. Results It was identified that in gene expression profiles of atrophic gastritis there were 165 genes showing a greater than 2-fold increase and 460 genes showing a greater than 50% decrease as compared to non-atrophic gastritis. RT-PCR analysis revealed similar results as in DNA microarray. Conclusions There is different expression in many genes between the gastric mucosal cells of non-atrophic and atrophic gastritis mucosa. Many genes expression profiles are involved in atrophic gastritis that would be of help in further understanding the development of atrophic gastritis.

Objective To investigate the main causes and strategies for the difficulties in ureteroscopic lithotripsy.Methods From March 2004 to December 2006,19 cases of ureteral calculi,who experienced difficulties during holmium laser lithotripsy or pneumatic lithotripsy under a rigid ureteroscope,were analyzed retrospectively.Among the cases,3 had difficulties in ureteroscope placement due to the narrow ureteral ingress,6 owing to calculus obstruction complicated with ureteral inflammatory polypi,4 resulted from twisted ureter,and 6 because of stenosis of the ureter.Results In 15 of the patients,the operation was successfully performed by changing surgical approach,controlling the hydraulic irrigation,and incising the stenotic segments,etc.Two patients,who had stenotic ureter,received ESWL with double-J catheter dwelling.Lithotripsy failed in 2 cases,and PCNL was used to remove the calculi.The postoperative complications occurred in 4 cases,including 2 with mucosal laceration and 2 ureteral perforations.One of the 4 cases was transferred to an open surgery,and the other 3 were cured by conservative treatments.Conclusions Holmium Laser lithotripsy and pneumatic lithotripsy under a rigid ureteroscope are safe and effective in treating ureteral calculi.

Objective To investigate whether a novel mucosal adjuvant (DNA containing six base pair motifs consisting of an unmethylated CpG dinucleotide flanked by two 5′ purines and two 3′ pyrimidines, CpG Oligodeoxynucleotide, CpG ODN),which has not been shown to have significant toxicity,could be an ideal mucosal adjuvant for the development of a H. pylori vaccine in mice model. Methods C57BL/6 mice were orally or intranasally immunized with H. pylori whole cell sonicate(WCS) / cholera toxin (CT) or WCS /CpG ODN, and the corresponding control groups were set. Mice were dosed once a week for four weeks. One week after the last immunization, all animals were challenged by live H. pylori (5?10 8) three times in a five day duration. Two and 8 weeks after the last challenge, all animals were sacrificed to examine infection of H. pylori. Sera, saliva, gastric juice were collected to measure the concentrations of IgG, IgG1, IgG2a and IgA by ELISA. Results The protecting rates against H. pylori infection were 75%(9/12), 70% (7/10) and 0 (0/10) in the group of WCS/CT orally, WCS/CpG ODN intranasally and WCS/CpG ODN orally, respectively. Significantly higher levels of serum IgG2a antibody was found in the group immunized with WCS plus CpG ODN than those found in the sham immunized controls ( P

Objective To compare the detection rates of capsule endoseopies with push endoseo-pies. Methods From May 2002 through January 2003 , thirty - nine patients with suspected small bowel diseases, particularly the gastrointestinal bleeding of unknown origin were examined by capsule endoscopies. Of the 39 patients. 32 complained of obscure recurrent gastrointestinal bleeding. From January 1993 to October 1996, 36 patients suffered from unexplained GI bleeding underwent push endoscopies. All patients had prior normal results on gastroseopy, colonoscopy, small bowel barium radiography, seintigraphy and/ or angiogra-phy. Results M2A capsule endoscopies disclosed abnormal small bowel findings in 26 out of 32 patients (81% ). Twenty one of 26 patients had significant pathological findings in explaining their clinical disorders with diagnostic yield of 66% (21 of 32 patients). Definite bleeding sites diagnosed by capsule endoscopies in 21 patients including angiodysplasia 8, inflammatory small bowel diseases 5, small bowel polyps 4, GI stro-mal tumor 2,earcinoid tumor and lipoma 1 , and bemorrhagie gastritis 1. Push endoscopies detected the definite sources of bleeding in 9 of 36 patients (25%). Definite bleeding sources included angiodysplasia 2, leiomyosareoma 2, leiomyoma 1 , lymphoma 1 , Grohns disease 1 , small bowel polyps 1 ,and adenocareinoma of ampulla 1. Suspected bleeding sources were seen with push endoscopies in two additional patients, and other five patients with capsule endoscopies. Conclusion Gapsule endoseopy is superior to push endoscopy in detecting obscure GI bleeding ( P

Objective To evaluate the effectiveness of wireless capsule endoscopies in patients with suspected CD of the small bowel.Methods From May 2002 through April 2003, we prospectively examined 20 suspected CD patients by capsule endoscopies with normal results in other conventional examinations. It includes the presence of the following symptoms and signs: abdominal pain, weight loss, positive fecal occult blood test, iron deficiency anemia, diarrhea and fever. Mean duration of symptoms before diagnosis was 6 5 years.Results Of the 20 participants, 13 (65%) were diagnosed as having CD of the small bowel according to the findings of the M2A Given Capsule. Among the findings detected by the capsule were mucosal erosions (2 patients), aphthae (5 patients), granulomatous nodularity (1 patient), large ulcers (2 patients), and ulceration with incomplete obstruction (3 patients). All of the 13 patients who received medications showed good clinical improvement.Conclusion Wireless capsule endoscopies were the effective device for diagnosing patients with suspected CD, undetected by conventional diagnostic measures.It may be more likely to detect early lesions in the small bowel of patients with CD.

objective To analyse the incidence of technical breakdown and clinical problem leading to the failure of capsule endoscopy examination and their influence on the diagnosis and to evaluate its feasibility and safety in special patient population.Methods A retrospective study of 300 consecutive patients referred to Renji Hospital for evaluation of suspected small bowel diseases between May 2002 and May 2006 was done.This included 300 consecutive patients.The median age of the patients was 51y (range,3～91Y).The young children group was defined as less than 10 years and the elderly group as more than 80 years.Technical problems were those related to the functioning of the equipment and clinical problems were those related to the patient.The incidence and the type of above-mentioned events and their influence on the diagnosis were analyzed.The safety and feasibility of the capsule endoscopy procedure were evaluated in the young children group,elderly group and patients with pacemakers,gastrectomy and Billroth Ⅱ gastrojejunostomy,intestinal diverticula,Crohn's disease and polyp of small intestine.Results A total of 300 patients were involved.The incidence of technical problems was 1.3%.including one case of failing in activating the capsule,one case of failing in loading the data and two cases of short life of battery.Failure of diagnosis was encountered in two cases.The incidence of clinical problems was 33.0%(99 cases)and they caused 35.4%(35 cases)failure of diagnosis in the 99 cases.Three patients in the young children group were unable to swallow the capsule and endoscope-guided overtube technique was used with success in all.In the elderly group.the incidence of capsule retaining in the oesophagus and stomach was as high as 23.0%.In two patients with pacemaker no interference between pacemaker and capsule was detected.In two patients with Billroth Ⅱ gastrojejunostomy uo capsule retention occurred.In 16 patients with diverticulum,capsule retention occurred in 1 case(6.0%).In 42 patients with Crohn's disease,capsule retention occurred in 5 cases.No acute gastrointestinal obstruction was found in the 42 patients with Crohn's disease and in 5 patients with polyp of small intestine.Conclusions With capsule endoscopy technical mistakes causing failure were very rare.The majority of the clinical problems were related to the inability capsule to reach the colon during the recording time.Capsule endoscopy provides a well-tolerated,safe and effective tool to investigate the gastrointestinal diseases.especially some small bowel diseases.

Objective To investigate the suppression effect of expressing parvovirus H-1 nonstructural protein 1 (NS1) gene on human gastric cancer cells and the possible mechanisms.Methods A recombinant enhanced green fluorescent protein (eGFP) labeled NS1 of parvovirus H-1 plasmid was constructed.Human gastric cancer cell line SGC7901 was transfected with recombinant plasmid (experiment group) or blank vector (negative control group) and blank control group was treated with equal amount of phosphate buffered saline (blank control group).After transfection,the distribution of fluorescent signal was observed under fluorescent microscope.The expression of NS1 at gene and protein level was measured.Cell growth curve of each group was drawn.The expression of cell senescence-associated β-galactosidase (SA-β-Gal) was tested.The changes of cell cycle were investigated by flowcytometry.Two groups' comparision was performed by t-test.Results After transfection,NS1 was expressed in SGC7901 cells at gene and protein level.Compared with negative control group,the fluorescent signal accumulated in cell nucleus in experiment group.The percentage of SA-β-Gal positive cell in experiment group ((30.5 ± 1.4) ％) was higher than that of negative control group ((4.4± 1.1) ％) and the difference was statistically significant (t =-12.931,P ＜ 0.01).The growth inhibition rate of SGC7901 cells from the first day to the fourth day was 45％,62％,73％ and 77％,respectively.The cell cycle of eGFP-NS1 expressed SGC7901 cells was arrested at G0/G1 phase.Conclusion Parvovirus H-1 NS1 play the role in cell nucleus of gastric cancer cell line SGC7901 and could make cell cycle arrested at G0/G1 phase,which effectively inhibited the proliferation SGC7901 cell.

OBJECTIVETo investigate the therapeutic effect of retroviral endostatin gene transfer on the human colon cancer cell line, LoVo.

METHODSA retroviral vector pLESSN expressing secretable endostatin was constructed and packaged with a titer of 8.2 x 10(5) CFU/ml. A LoVo cell line was subjected to retrovirus-mediated endostatin gene transfer. The proviral integration of endostatin was analyzed with PCR. The function of endostatin was tested by MTT assay in vitro and a mouse xenograft model in vivo.

RESULTSAfter transfection and superinfection, amphotropic retrovirus was collected, and transduction with amphotropic retroviruses resulted in endostatin proviral integration. The endostatin secreted by transduced LoVo cells markedly inhibited cell growth up to 67% (P<0.001), compared with the control cells. The gene expression of endostatin in LoVo colon tumor cells significantly inhibited tumor growth in vivo. There was an 86% reduction in tumor size in the endostatin-transduced group, accompanied by a reduction in vessels, compared with the control group (P<0.01).

CONCLUSIONRetroviruses can allow functional expression of the endostatin gene in human colon tumors, showing promise for an antitumor strategy using antiangiogenesis.

Cell Division ; Cell Line, Tumor ; Colonic Neoplasms ; pathology ; therapy ; Endostatins ; genetics ; Gene Transfer Techniques ; Genetic Vectors ; Humans ; Retroviridae