胃转流术后远端肠黏膜形态及生长因子表达的变化

目的：探讨胃转流术后远端肠管黏膜的适应性变化及生长因子的表达情况。方法：将8周龄的Wistar大鼠随机分为对照组、假手术组和胃转流术组,术后8周取吻合口远端肠管行常规病理切片检查,测量肠黏膜厚度和绒毛高度,采用免疫荧光法检测肠粘膜中表皮生长因子（EGF）和胰岛素样生长因子-1（IGF—1）的表达。结果：胃转流术组黏膜厚度（672±39与500±31um,P〈0．01）和绒毛高度（445±19与342±15um,P〈0．01）均显著高于假手术组（P〈0．01）,而对照组和假手术组间均无显著差异。与假手术组比较,胃转流术组肠粘膜中EGF和IGF-1的表达显著升高（P〈0．01）,而对照组和假手术组间无显著差异。结论：胃转流术后远端肠管粘膜发生适应性增生,同时伴随着EGF和IGF—1表达水平的升高。     

晚期胃癌患者化疗中胸腺肽α1治疗疗效的临床研究

目的：探讨应用流式细胞仪（FCM）检测胃癌患者外周血免疫指标,以评价胸腺肽α1联合化疗对胃癌患者免疫功能的影响。方法：70例胃癌患者随机分为用药组和对照组。用药组35例采用胸腺肽α1＋化疗,对照组35例单用化疗,两组化疗方案相同。胸腺肽α1每次1.6mg,每周2次,连续4周（共8针）。28天为一疗程,共用2个疗程。采用FCM检测两组患者化疗前后外周血CD4、CD8、CD3＋CD4＋、CD3＋CD8＋免疫指标。结果：用药组CD4、CD8、CD3＋CD4＋、CD4/CD8均高于化疗前和对照组化疗后水平,均具有统计学意义（P〈0.05）。结论：胸腺肽α1配合化疗能提高患者的免疫功能,用FCM检测外周血免疫指标为临床观察肿瘤患者的免疫状态提供有效的依据。     

PIK3CA 基因突变的MassARRAY 分子量阵列分析

目的:利用MassARRAY分子量阵列分析系统检测胃癌组织PIK3CA基因突变。方法:从胃癌石蜡包埋组织中提取基因组,PCR反应扩增目的基因片段,MassARRAY分子量阵列分析系统检测PIK3CA基因突变;焦磷酸测序验证检测结果。结果:中国西部地区144例胃癌组织样本中PIK3CA_E542K(1624G>A)突变携带率为77.6%,PIK3CA_E545K(1633G>A)突变携带率为84%。MassARRAY分子量阵列分析系统检测结果与焦磷酸测序结果达到100%吻合。结论:建立了MassARRAY分子量阵列分析系统检测基因突变的方法,初步建立了中国西北地区汉族人群胃癌组织PIK3CA基因PIK3CA_E542K(1624G>A)和PIK3CA_E545K(1633G>A)位点突变频数。     

Detection of non-pylori Helicobacter species in "Helicobacter heilmannii"-infected humans

BACKGROUND: A small proportion of patients suffering from chronic active gastritis are diagnosed with gastric Helicobacter species other than Helicobacter pylori. Circumstantial evidence has suggested that these bacteria, also referred to as "Helicobacter heilmannii"-like organisms (HHLO), may be transmitted through animals. The isolation of a Helicobacter bizzozeronii strain from a human patient confirmed this hypothesis. It was the aim of the present study to assess the presence of animal Helicobacter species and H. pylori in humans infected with HHLO, as diagnosed by histology. METHODS: Paraffin-embedded gastric biopsy specimens of 108 HHLO-infected patients (42 women and 66 men) from three clinical centers were screened for the presence of animal gastric Helicobacter species by polymerase chain reaction (PCR), using assays targeting the 16S rDNA region of the three known canine and feline helicobacters (H. bizzozeronii, H. salomonis and H. felis), "Candidatus H. suis", and "Candidatus H. bovis". In addition, the presence of H. pylori was evaluated by multiplex PCR analysis. RESULTS: In 63.4% of the stomachs (64/101) classification of the Helicobacter infection into the above mentioned groups was achieved. Non-pylori Helicobacter species commonly colonizing the stomachs of cats and dogs were found in 48.5% (49/101) of the patients. Fourteen (13.9%) samples tested positive for "Candidatus H. suis", and "Candidatus H. bovis" was demonstrated in 1 (0.9%) patient. The presence of H. pylori was established in 13 patients (12.9%). Eleven stomachs (10.9%) were infected with at least two different Helicobacter species. CONCLUSIONS: This study identifies animal Helicobacter species in the stomach of a large series of HHLO-infected patients, which may have clinical implications in a subset of patients with gastric disease.     

Helicobacter pylori antibodies and gastric cancer: a gender-related difference

Helicobacter pylori has been proposed as a causative agent of gastric cancer. The aim of this study was to define serum antibodies response against different H. pylori antigens in patients with gastric cancer. Serum samples were collected from 115 Lithuanian patients with non-cardia gastric cancer and 110 age- and sex-matched controls without cancer. Heat-stable, low-molecular-mass, and outer membrane proteins were used as antigens to analyze serum IgG antibody response against H. pylori by enzyme-linked immunosorbent assay. Seroprevalence of H. pylori using low-molecular-mass antigen was significantly higher in gastric cancer patients, compared to controls (77% versus 57%, p<0.05). Significant differences in the prevalence of H. pylori infection between gastric cancer patients and controls were found in females using all three studied antigens: heat-stable (98% versus 84%, p<0.05), low-molecular-mass (88% versus 48%, p<0.05) and outer membrane proteins (78% versus 57%, p<0.05). In males, no significant differences were revealed between gastric cancer patients and controls. There may be other cofactors in addition to H. pylori that are important for the development of gastric cancer. H. pylori seems, however, to be a more important for development of gastric cancer in females than in males or males may have more confounding risk factors for gastric cancer than females.     

Matrix metalloproteinase 11 depletion inhibits cell proliferation in gastric cancer cells

Our previous study has shown that matrix metalloproteinase 11 (MMP11) is highly expressed in tumor cell lines and primary tumor of gastric cancer (GC). In order to reveal the correlation between expression of MMP11 and biological features of GC cell, we have constructed the recombinant plasmids producing hairpin small interfering RNA (siRNA) to target MMP11 mRNA using a vector-based RNA interference technology. Stable transfection of recombinants into GC cell line BGC823 specifically depleted the mRNA and protein of MMP11 as demonstrated by RT-PCR and Western blotting analysis. The siRNA-treated cells exhibited significantly decreased growth ability compared with mock transfectants and parental BGC823 cells. Furthermore, colony formation of MMP11 deficient cells was dramatically inhibited in soft agar and tumorigenicity was reduced in nude mice, respectively. These results provide new insights into the function of MMP11 and suggest that MMP11 may play an important role in the control of cell proliferation and tumor development in GC.     

Salicylic acid-induced inactivation of creatine kinase in the presence of lactoperoxidase and H2O2

To clarify one mechanism of aspirin-induced gastric mucosal damage, inactivation of creatine kinase (CK) by salicylic acid that is easily produced from aspirin in vivo was examined in the presence of lactoperoxidase (LPO) and H2O2 (LPO-H2O2). Salicylic acid inactivated CK (rabbit muscle) during its interaction with LPO-H2O2. CK activity in gastric mucosal homogenate decreased dependent on the concentration of salicylic acid in the presence of LPO-H2O2. Oxygen radical scavengers did not prevent the inactivation of CK. Direct detection of free radicals of salicylic acid by electron spin resonance was unsuccessful. However, glutathionyl radicals were formed during the interaction of salicylic acid with LPO-H2O2 in the presence of reduced glutathione and 5,5-dimethyl-1-pyrroline oxide as a spin trap agent. Among salicylic acid-related drugs, salsalate, but not aspirin and ethenzamide, inactivated CK, indicating the phenolic hydroxyl group is oxidized by LPO-H2O2. During oxidation of salicylic acid by LPO-H2O2, the sulfhydryl group in CK markedly decreased, and salicylic acid bound to CK. These results indicate that CK was inactivated through loss of the sulfhydryl group and binding of salicylic acid.     

Defective CD3zeta chain expression in Herpesvirus saimiri (HVS)-derived T-cell lines in gastric adenocarcinoma

Low expression of the CD3zeta chain has been reported in patients with cancer and it has been suggested that tumor-derived factors are involved in its downregulation. The expression of CD3zeta chain was measured in T-cell lines from patients with gastric adenocarcinoma and healthy volunteers and grown in vitro for several months and, hence, in the absence of any tumor-derived factors. T-cell lines of mucosal origin were obtained by Herpesvirus saimiri transformation from gastric cancer patients. The expression of CD3zeta and CD3epsilon was measured by flow cytometry and Western-blot analysis. Calcium mobilization and apoptosis rate were also measured. The levels of CD3zeta, but not CD3epsilon, chain on the cell surface were significantly reduced in T-cell lines derived from patients with gastric cancer when cultured in the absence of IL-2. Western-blot analysis of total cell extracts or lipid raft fractions confirmed this finding. Calcium mobilization, a measure of signal transduction, was reduced in T cell lines from patients with gastric cancer. We conclude that T cells from patients with cancer express lower levels of CD3zeta. This downregulation is not caused by a direct effect of tumor-derived factors but, rather, it appears to be inherent to the patient cells. The low CD3zeta expression would render T lymphocytes unable to control the growth of tumor cells.     

Gastric and thymic assay of acute oral treatment of rats with nitric oxide esters of ibuprofen or indomethacin

Two common non-steroidal anti-inflammatory drugs (NSAIDs) and their nitric oxide (NO) adducts were evaluated for effects on stomach and thymus. Following 4-h duration (acute) oral dosing of fasted male Wistar rats, 1.33 x 10(-4)mol/kg of ibuprofen caused significant visual irritation score and microscopic thinning, although an ulceration assay proved insensitive. Ibuprofen esterified with NO abolished irritation and significantly reduced thinning. Gastro-protective effects of NO-linked ibuprofen were associated with higher levels of diaphorase by optical density, an enzymatic marker of local synthesis of nitric oxide. Both indomethacin and its congener at 2 x 10(-5)mol/kg produced microscopic signs of thinning only, not visible irritation or alteration of diaphorase staining. Results suggest that NO-linked ibuprofen can promote resistance to mucosal injury, possibly via local synthesis of NO. All NO-congeners and parent NSAIDs produced comparable reductions in the abundance of medullary nitrergic cells, those synthesising NO in thymus, without significantly lowering T-cellularity, the relative size of cortex wherein T-cells are produced. Findings indicate disturbance of T-cell tolerance, consistent with increased risk of autoimmune susceptibility.