Gastric juice acidity in upper gastrointestinal diseases

AIM: To search the independent factors determining gastric juice acidity and to investigate the acidity of gastric juices in various benign and malignant upper gastrointestinal diseases. METHODS: Fasting gastric juice acidity of 165 healthysubjects and 346 patients with esophageal ulcer (n = 21), gastric ulcer (n = 136), duodenal ulcer (n = 100) or gastric cancer (n = 89) were measured and compared. Additionally, gastric specimens were taken from the antrum and body for rapid urease test and histological examination. RESULTS: Multivariate analysis revealed that bile stain of gastric juice, high acute inflammatory score of the corpus, and atrophy of the corpus were independent risk factors for the development of gastric hypoacidity with odds ratios of 3.1 (95% CI: 1.3-7.3), 3.1 (95% CI: 1.2-7.9) and 3.5 (95% CI: 1.3-9.2). Esophageal ulcer and duodenal ulcer patients had a lower pH level (1.9 and 2.1 vs 2.9, both P < 0.05) of gastric juices than healthy subjects. In contrast, gastric ulcer and gastric cancer patients had a higher pH level (3.4 and 6.6 vs 2.9, both P < 0.001) than healthy controls. Hypoacidity existed in 22%, 5%, 29%, 5% and 88% of healthy subjects, esophageal ulcer, gastric ulcer, duodenal ulcer and gastric cancer patients, respectively. CONCLUSION: Bile reflux, atrophy and dense neutrophil infiltrate of the corpus are three independent factors determining the acidity of gastric juice.

Microbiome changes in the gastric mucosa and gastric juice in different histological stages of Helicobacter pylori-negative gastric cancers

BACKGROUND The gastric microbiota in patients with gastric cancer(GC)has received increasing attention,but the profiling of the gastric microbiome through the histological stages of gastric tumorigenesis remains poorly understood,especially for patients with Helicobacter pylori-negative GC(HPNGC).AIM To characterize microbial profiles of gastric mucosa and juice for HPNGC carcinogenesis and identify distinct taxa in precancerous lesions.METHODS The 16S rRNA gene analysis was performed on gastric mucosa from 134 Helicobacter pylori-negative cases,including 56 superficial gastritis(SG),9 atrophic gastritis(AG),27 intestinal metaplasia(IM),29 dysplasia(Dys),and 13 GC cases,to investigate differences in gastric microbial diversity and composition across the disease stages.In addition,paired gastric mucosa and juice samples from 18 SG,18 IM,and 18 Dys samples were analyzed.α-Diversity was measured by Shannon and Chao1 indexes,andβ-diversity was calculated using partial least squares discrimination analysis(PLS-DA).Differences in the microbial composition across disease stages in different sample types were assessed using the linear discriminant analysis effect size.RESULTS The diversity and composition of the bacterial microbiota in the gastric mucosa changed progressively across stages of gastric carcinogenesis.The diversity of the gastric mucosa microbiota was found to be significantly lower in the IM and Dys groups than in the SG group,and the patients with GC had the lowest bacterial community richness(P<0.05).Patients with IM and those with Dys had similar gastric mucosa microbiota profiles with Ralstonia and Rhodococcus as the predominant genera.Microbial network analysis showed that there was increasing correlation strength between IM and Dys(|correlation threshold|≥0.5,P<0.05).GC and its precancerous lesions have distinguishable bacterial taxa;our results identified HPNGC-associated bacteria Streptococcaceae and Lactobacillaceae(P<0.05).Additionally,across precancerous lesion stages from AG to Dys in Helicobacter pylori-negative patients,Burkholderiaceae abundance continuously increased,while Streptococcaceae and Prevotellaceae abundance presented a continuous downward trend.Furthermore,the microbial diversity was higher in gastric juice(P<0.001)than in the mucosa,while PLS-DA revealed a statistically significant difference between the two groups(ANOSIM,P=0.001).A significant difference in the microbial structure was identified,with Proteobacteria being more prevalent in the gastric mucosa and Firmicutes being more abundant in gastric juice.CONCLUSION Our results provide insights into potential taxonomic biomarkers for HPNGC and its precancerous stages and assist in predicting the prognosis of IM and Dys based on the mucosal microbiota profile.

Gastric juice for the diagnosis of H pylori infection in patients on proton pump inhibitors

AIM: To determine the efficacy of gastric juice polymerase chain reaction (PCR) for the detection of H pylori infection in comparison with histology and gastric antral biopsy PCR in patients on a proton pump inhibitor (PPI). METHODS: Eighty-five consecutive patients with dyspeptic symptoms were enrolled. Gastric biopsies for histology, PCR and gastric juice were collected at endoscopy for PCR of the H pylori urease C gene (ure C). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, positive and negative likelihood ratio for PCR of gastric juice for the H pylori ure C gene was compared to histology and gastric antral biopsy H pylori ure C PCR in patients with and without PPI. RESULTS: Gastric juice PCR was positive in 66 (78%) patients. Histology showed H pylori associated gastritis in 57 (67%). Gastric biopsy PCR was positive in 72 (85%). In patients not taking PPI, the sensitivity, specificity, PPV, NPV, accuracy and positive and negative likelihood ratio for gastric juice PCR were 89%, 72%, 91%, 67%, 90%, 85%, 3.1 and 0.1 respectively. In patients on PPI these values were 86%, 100%%, 100%, 29%, 86%, 9.5 and 1.4, respectively. CONCLUSION: Gastric juice PCR for the diagnosis of H pylori infection has increased sensitivity compared to histology with PPI. The use of gastric juice PCR is recommended to confirm H pylori status in patients taking PPIs.

Intraprocedural gastric juice analysis as compared to rapid urease test for real-time detection of Helicobacter pylori

BACKGROUND Endofaster is an innovative technology that can be combined with upper gastrointestinal endoscopy(UGE)to perform gastric juice analysis and real-time detection of Helicobacter pylori(H.pylori).AIM To assess the diagnostic performance of this technology and its impact on the management of H.pylori in the real-life clinical setting.METHODS Patients undergoing routine UGE were prospectively recruited.Biopsies were taken to assess gastric histology according to the updated Sydney system and for rapid urease test(RUT).Gastric juice sampling and analysis was performed using the Endofaster,and the diagnosis of H.pylori was based on real-time ammonium measurements.Histological detection of H.pylori served as the diagnostic gold standard for comparing Endofaster-based H.pylori diagnosis with RUT-based H.pylori detection.RESULTS A total of 198 patients were prospectively enrolled in an H.pylori diagnostic study by Endofasterbased gastric juice analysis(EGJA)during the UGE.Biopsies for RUT and histological assessment were performed on 161 patients(82 men and 79 women,mean age 54.8±19.2 years).H.pylori infection was detected by histology in 47(29.2%)patients.Overall,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value(NPV)for H.pylori diagnosis by EGJA were 91.5%,93.0%,92.6%,84.3%,and 96.4%,respectively.In patients on treatment with proton pump inhibitors,diagnostic sensitivity was reduced by 27.3%,while specificity and NPV were unaffected.EGJA and RUT were comparable in diagnostic performance and highly concordant in H.pylori detection(κ-value=0.85).CONCLUSION Endofaster allows for rapid and highly accurate detection of H.pylori during gastroscopy.This may guide taking additional biopsies for antibiotic susceptibility testing during the same procedure and then selecting an individually tailored eradication regimen.

Exposure to gastric juice may not cause adenocarcinogenesis of the esophagus

AIM: To determine the effects of gastric juice on the development of esophageal adenocarcinoma (EAC). METHODS: A animal model of duodenogastroesophageal reflux was established in Sprague-Dawley rats undergoing esophagoduodenostomy. The development of EAC and forestomach adenocarcinoma was investigated 40 wk after the treatment. Intraluminal pH and bile of the forestomach were measured. RESULTS: There were no significant differences in pH (t=0.117, P=0.925) or bile (χ2=0.036, P=0.85) in the forestomach before and 40 wk after esophagoduodenostomy. There were also no significant differences between the model and controls during esophagoduodenostomy or 40 wk after esophagoduodenostomy. The incidence of intestinal metaplasia (88%) and intestinal metaplasia with dysplasia and adenocarcinoma (28%) in the esophagus in the model was higher than in the controls 40 wk after surgery (χ2=43.06, P < 0.001 and χ2=9.33, P=0.002, respectively) and in the forestomach in the model (χ2=32.05, P < 0.001 and χ2=8.14, P=0.004, respectively). The incidence rates of inflammation in the esophagus and forestomach were 100% and 96%, respectively (χ2=1.02, P=0.31) in the model, which was higher than in the esophageal control (6.8%) (χ2=42.70, P < 0.001). CONCLUSION: Gastric juice exposure may not cause intestinal metaplasia with dysplasia or adenocarcinoma of the forestomach and may not be related to EAC.

THE STUDY ON EPIDERMAL CROWTH FACTOR LEVEL IN GASTRIC JUICE OF PATIENTS WITH MALIGNANT OR BENIGN GASTRODUODENAL DISEASES

The epidermal growth factor (EGF) was studied by RIA in gastric juice of patients with gastroduodenal diseases. The concentration of EGF (pg/ml) is significantly higher in gastric cancer group than in the benign group (51. 48±3.77, n= 30 vs 31. 62 ± 3. 11, n= 136). The value disperse extensively In gastric cancer group, but they locate mostly in lower range in the benign group. The percentage of the cases with level higher than or equal to average level of all benign cases is 46. 7% in gastric cancer group and 26. 5% in the benign group (P<0. 05). The results suggest that EGF is related to gastric cancer.

Carcinogenic potential of duodenal reflux juice from patients with long-standing postgastrectomy

AIM: To determine whether study on the carcinogenic potential of reflux juice from patients with remote gastrectomy could clarify the inherent relationship between duodenal reflux and gastric stump cancer. METHODS: A total of 37 reflux juice samples (13 Billroth I, 24 Billroth II) were employed in the present study. A two-stage transformation assay using BALB/c 3T3 cells was carried out to test the initiating or promoting activity of these samples. RESULTS: Two of 18 (11.1%) reflux samples exerted initiating activities, whereas 9/19 (47.4%) samples enhanced the MNNG-initiating cell transformation, suggesting the duodenal reflux juice might more frequently possess the tumor-promoter activity (P = 0.029). In addition, there was no difference in initiating activities of the samples irrespective of surgical procedures (P = 0.488), while Billroth II samples exhibited stronger tumor-promoter activity than Billroth I samples (P = 0.027). Furthermore, the promoter activities were well correlated with the histological changes of the stomas (r(s) = 0.625, P = 0.004), but neither their cytotoxicities nor initiating activities had this correlation (Probabilities were 0.523 and 0.085, respectively). CONCLUSION: The duodenal reflux juice from patients with remote postgastrectomy did have carcinogenic potential, and suggested that tumor-promoting activity should principally account for the high incidence of gastric cancer in gastrectomy patients. In contrast, it is difficult to explain the high stump-cancer incidence with the N-nitroso compounds theory-a popular theory for the intact stomach carcinogenesis, and it seemed to be justified to focus chemo-prevention of this cancer on the tumor-promoting potential of reflux juice.

Should peri-gastrectomy gastric acidity be our focus among gastric cancer patients?

AIM: To investigate the necessity and correctness of acid suppression pre- and post-gastrectomy among gastric carcinoma (GC) patients.

幽门螺杆菌阴性的慢性萎缩性胃炎患者胃液微生物群特征分析

目的探究幽门螺杆菌阴性慢性萎缩性胃炎(CAGn)患者的胃液微生物群组成,寻找可能与CAGn发生相关的胃液微生物群。方法选取2020—2021年到兰州大学第一医院外科内镜中心接受胃镜检查的48例患者作为研究对象,其中幽门螺杆菌阴性慢性非萎缩性胃炎(CNAGn)患者21例,CAGn患者27例。收集胃液标本,使用16S rRNA三代全长测序技术测定分析两组患者的胃液微生物群组成。结果CAGn组的平均年龄高于CNAGn组[(52.33±12.20)岁vs.(40.67±7.95)岁,P=0.0004]。两组患者微生物α多样性及β多样性无明显差异,微生物群整体组成较为相似。组间差异显著性分析发现了CNAGn组显著富集的11个属和CAGn组显著富集的2个属。结论本研究筛选出CAGn患者的差异性非幽门螺杆菌微生物,这些差异微生物可能为CAGn患者的诊断和治疗提供参考。

一种新型胃液回收及存储装置的设计与应用

肠内营养是重症患者营养支持的首选方法,胃残余量监测能够很好的评估胃肠动力和肠内营养的耐受情况,也是识别高误吸风险最常用的指标。目前注射器回抽法是临床监测胃残余量最常用的方法。本研究介绍了一款实用新型胃液回收及存储装置的设计和使用方法,旨在有效降低二次污染的发生风险,同时减轻医护人员的工作负担,提高工作效率。

虾蛄生物可给性镉标准化检测方法研究

优化了虾蛄生物可给性镉检测方法的样品处理条件。运用简单的生物可给性提取技术,参照《中国药典》药物溶出度与释放度、崩解时限检查法,结合膳食摄入水平,以虾蛄为研究对象,探讨了料液比、模拟人工胃液pH值、消化时间等参数对检测结果的影响,采用响应面法对虾蛄生物可给性镉的最佳消化条件进行了优化,建立了相应的检测模型。结果表明,料液比为0.5 g/mL,人工胃液pH值调至1.1,消化时间2 h,消化温度为(37±1)℃时,生物可给性镉检测效率最高。优化后的虾蛄生物可给性镉检测方法为实现重金属人体生物可给性实验方法的标准化提供了一种解决方案。

丁香抗氧化活性物质提取及人工胃肠液对其活性的影响

采用水浴振荡、超声、微波和超声-微波协同对丁香抗氧化活性物质进行了提取,并用人工胃、肠液对有效部位进行了处理。结果表明,在4种提取方法中,协同提取和微波提取总多酚、总黄酮得率以及抗氧化能力要优于另外2种方法,协同提取时间仅为微波提取的1/2,协同提取效率最高。人工胃液处理后,丁香有效部位抗氧化活性得到显著提高(P<0.001),而人工肠液处理后,其抗氧化活性却显著性降低(P<0.001)。

化浊解毒方对慢性萎缩性胃炎胃癌前病变患者胃液成分及肿瘤标记物的影响

目的观察化浊解毒方对慢性萎缩性胃炎癌前病变的临床疗效及对胃液中乳酸、总酸、亚硝酸盐及游离酸和胃液及血中肿瘤标记物的影响。方法 229例慢性萎缩性胃炎癌前病变患者随机分为两组,治疗组119例给予化浊解毒方口服,对照组110例给予胃复春片口服,3个月为1个疗程,共治疗2个疗程。观察两组临床疗效及胃酸的含量,运用电化学发光免疫分析法检测胃液和血液中肿瘤标记物的含量。结果治疗组临床病理有效率为83.2%(99/119),对照组为60.9%(67/110),两组病理总有效率比较,差异有统计学意义(P<0.05);两组均能显著提高胃液中总酸和游离酸的含量并降低乳酸及亚硝酸盐的含量,且能显著降低胃液及血清中癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原19-9(carbohydrate antigen19-9,CA19-9)、糖类抗原72-4(carbohydrate antigen72-4,CA72-4)、糖类抗原125(carbohydrate antigen125,CA125)的含量,与对照组比较,治疗组作用更明显(P<0.05)。结论化浊解毒方能刺激胃黏膜的分泌功能,提高胃液总酸度和游离酸的含量;通过降低胃液中乳酸及亚硝酸盐的含量和胃液及血清中CEA、CA19-9、CA72-4、CA125的含量,阻止胃癌前病变的进一步发展。

纳豆发酵及后处理生产工艺对纳豆激酶活性的影响

跟踪了纳豆发酵过程中纳豆激酶的变化。考察了纳豆冻干粉在模拟胃肠环境、冷冻干燥以及破碎过程中的酶活损失情况,为纳豆胶囊生产过程中工艺确立、剂型选择和食用方法提供了技术基础。

蒙脱石散对氧氟沙星体外吸附作用研究

目的:研究蒙脱石散对氧氟沙星的体外吸附作用。方法:取不同剂量的氧氟沙星与蒙脱石散分别混合于人工胃液和人工肠液中,(37±0.5)℃水浴恒温1h后过滤,采用紫外分光光度法测定氧氟沙星的含量变化。结果:在人工胃液和人工肠液中,蒙脱石散对氧氟沙星的吸附率分别为(99.76±0.01)%和(99.55±0.02)%。结论:蒙脱石散在人工胃液和人工肠液中对氧氟沙星有强大的吸附作用,应避免同时服用2药。

胃液CEA、CA_(19-9)联检在胃癌预后判断与复发筛查中的价值

目的 探讨胃液中癌胚抗原(CEA)、糖链多肽抗原19-9(CA19-9)在胃癌预后判断和复发筛查中的价值。方法应用免疫放射法检测了62例胃癌患者(术后复发组32例,未复发组30例)手术前后胃液中CEA、CA19-9变化,并进行随访观察。结果复发组CEA为(65.81±43.62)ng/ml,CA19-9为(172.53±159.38)U/ml。两组比较,有非常显著差异(P<0.01)。CEA、CA19-9联检可将敏感性提高至81.25％,并可在胃癌术后亚临床期检出复发。结论 胃液CEA、CA19-9联检对胃癌疗效观察、预后判断和复发筛查具有重要意义。

模拟人体胃肠道环境对儿茶素稳定性的影响

为研究模拟人体胃肠道环境对儿茶素稳定性的影响,利用高压液相色谱技术测定了不同时点儿茶素在不同pH溶液及人工模拟体胃液与肠液中的含量.结果表明,儿茶素在pH5.8时最稳定,人工模拟胃液对儿茶素具有较强的破坏力,而人工模拟肠液对儿茶素的稳定性影响相对较小;胃蛋白酶、胰蛋白酶以及缓冲溶液中盐类物质并不影响儿茶素的稳定性.

斜带石斑鱼消化道乳酸菌在模拟胃肠道环境中的存活

从斜带石斑鱼(Epinephelus coioides)幼鱼消化道分离到3株乳酸菌,通过抑菌试验筛选出抑菌效果较好的2株菌(MM1和MM4),经生理生化鉴定结合16SrRNA基因测序分析,MM1菌株鉴定为乳酸乳球菌(Lactococcus lactis),MM4菌株鉴定为屎肠球菌(Enterococcus faecium)。进一步研究了MM1和MM4的体外生长特性,及其对不同pH值的人工胃液、含有不同浓度胆盐的人工肠液及高温的耐受能力。结果表明,MM1和MM4均在培养6h左右进入对数生长期。对人工胃液的耐受能力相似,pH4.0和3.0的人工胃液对2株菌存活的影响较小,而pH2.0的人工胃液对2株菌的影响较大,经2h处理后两者的存活数即下降到105CFU/mL,经4h处理后的存活数低于5.0×103CFU/mL。MM1和MM4对含不同浓度胆盐的人工肠液均具有较好的耐受能力,含中低浓度胆盐(0.1%～0.3%)的人工肠液对2株菌的存活影响很小,处理3h后2株菌的存活数均维持在107CFU/mL以上;高浓度胆盐(0.5%～0.7%)处理3h后2株菌的存活数明显下降,但活菌数仍维持在105CFU/mL以上。MM1和MM4具有一定的耐高温能力,60℃处理30min二者存活数在107CFU/mL以上;80℃处理30min二者存活数在106CFU/mL以上。结论认为,2株乳酸菌具有生长速度快、抑菌能力强、对胃肠道环境和高温耐受能力较强的特点,具有作为益生菌的应用潜力。

四乙酰葛根素在模拟人体胃肠环境中的稳定性研究

目的考察四乙酰葛根素(4ac)在模拟人胃肠环境的稳定性。方法采用高效液相色谱法测定4ac的降解剩余百分含量。结果 4ac在0.0625～1.0mg/ml浓度范围内线性良好,平均回收率为101.05%(RSD=1.59%)。人工肠液(加酶和不加酶)中,4ac在室温25℃和37℃时较稳定;人工胃液(加酶和不加酶)中,4ac在室温25℃和37℃时不稳定,半衰期分别为18.99,9.76,13.33h和8.22h。结论 4ac在人工肠液中稳定性较好,可开发肠溶制剂。

氢溴酸槟榔碱抗实验性胃溃疡效果研究

目的研究氢溴酸槟榔碱抗实验性胃溃疡的作用。方法用化学测定法观察氢溴酸槟榔碱对大鼠胃液胃酸、胃蛋白酶分泌的影响;采用小鼠应激性胃溃疡模型、大鼠乙醇型胃溃疡模型和乙酸灼烧型大鼠胃溃疡模型来观察氢溴酸槟榔碱对胃溃疡动物模型的作用。结果氢溴酸槟榔碱可显著减少胃游离酸及总酸量,降低胃蛋白酶活性;对小鼠应激性胃溃疡、大鼠乙醇型胃溃疡、大鼠乙酸型胃溃疡等具有明显的抑制和保护作用。结论氢溴酸槟榔碱具有抗实验性胃溃疡的作用。