0
selected
-
1.
Nanomechanical Hallmarks of Helicobacter pylori Infection in Pediatric Patients.
Deptuła, P, Suprewicz, Ł, Daniluk, T, Namiot, A, Chmielewska, SJ, Daniluk, U, Lebensztejn, D, Bucki, R
International journal of molecular sciences. 2021;(11)
Abstract
BACKGROUND the molecular mechanism of gastric cancer development related to Helicobacter pylori (H. pylori) infection has not been fully understood, and further studies are still needed. Information regarding nanomechanical aspects of pathophysiological events that occur during H. pylori infection can be crucial in the development of new prevention, treatment, and diagnostic measures against clinical consequences associated with H. pylori infection, including gastric ulcer, duodenal ulcer, and gastric cancer. METHODS in this study, we assessed mechanical properties of children's healthy and H. pylori positive stomach tissues and the mechanical response of human gastric cells exposed to heat-treated H. pylori cells using atomic force microscopy (AFM NanoWizard 4 BioScience JPK Instruments Bruker). Elastic modulus (i.e., the Young's modulus) was derived from the Hertz-Sneddon model applied to force-indentation curves. Human tissue samples were evaluated using rapid urease tests to identify H. pylori positive samples, and the presence of H. pylori cells in those samples was confirmed using immunohistopathological staining. RESULTS AND CONCLUSION collected data suggest that nanomechanical properties of infected tissue might be considered as markers indicated H. pylori presence since infected tissues are softer than uninfected ones. At the cellular level, this mechanical response is at least partially mediated by cell cytoskeleton remodeling indicating that gastric cells are able to tune their mechanical properties when subjected to the presence of H. pylori products. Persistent fluctuations of tissue mechanical properties in response to H. pylori infection might, in the long-term, promote induction of cancer development.
-
2.
Prospective study of Helicobacter pylori antigens and gastric noncardia cancer risk in the nutrition intervention trial cohort.
Murphy, G, Freedman, ND, Michel, A, Fan, JH, Taylor, PR, Pawlita, M, Qiao, YL, Zhang, H, Yu, K, Abnet, CC, et al
International journal of cancer. 2015;(8):1938-46
-
-
Free full text
-
Abstract
Helicobacter pylori (H. pylori) infection is the strongest known risk factor for gastric noncardia adenocarcinoma (GNCA). We used multiplex serology to determine whether seropositivity to 15 H. pylori proteins is associated with the subsequent development of noncardia gastric cancer in Linxian, China. We included 448 GNCA cases and 1242 controls from two time points within the Linxian General Population Nutrition Intervention Trial, Linxian. H. pylori multiplex seropositivity was defined as positivity to ≥4 of the 15 included antigens. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for major GNCA risk factors. In addition, we undertook a meta-analysis combining H. pylori multiplex serology data from both time points. H. pylori multiplex seropositivity was associated with a significant increase in risk of GNCA at one time point (1985; OR: 3.44, 95% CI: 1.91, 6.19) and this association remained significant following adjustment for H. pylori or CagA ELISA seropositivity (OR: 2.92, 95% CI: 1.56, 5.47). Combining data from both time points in a meta-analysis H. pylori multiplex seropositivity was associated with an increased risk of GNCA, as were six individual antigens: GroEL, HP0305, CagA, VacA, HcpC and Omp. CagM was inversely associated with risk of GNCA. We identified six individual antigens that confer an increase in risk of GNCA within this population of high H. pylori seroprevalence, as well as a single antigen that may be inversely associated with GNCA risk. We further determined that the H. pylori multiplex assay provides additional information to the conventional ELISA methods on risk of GNCA.
-
3.
The association between current Helicobacter pylori infection and coronary artery disease.
Jin, SW, Her, SH, Lee, JM, Yoon, HJ, Moon, SJ, Kim, PJ, Baek, SH, Seung, KB, Kim, JH, Kang, SB, et al
The Korean journal of internal medicine. 2007;(3):152-6
Abstract
BACKGROUND The role of Helicobacter pylori (H. pylori) in the pathogenesis of coronary artery disease (CAD) is still controversial, and the relation between current H. pylori infection and CAD has not been fully examined. This study evaluated the relation between H. pylori infection as confirmed by gastroduodenoscopic biopsy and CAD. METHODS We determined the presence of H. pylori infections, via gastroduodenoscopy, in 88 patients of the normal coronary angiographic group and also in 175 patients of the CAD group, and the latter patients had more than 50% coronary stenosis angiographically demonstrated. We excluded those patients with a history of previous H. pylori eradication and/or malignancy. A small piece of tissue from the antrum, which was obtained by gastroduodenoscopic biopsy, was stained by Warthin-starry silver stain. We defined a negative staining result that there was no stained tissue in the sample and the stained tissue was also positive for H. pylori infection. RESULTS There was no significant difference, except for gender, age, smoking and high density lipoprotein cholesterol (HDL-c), of the demographic and laboratory characteristics between the groups. Twenty seven (30.7%) patients of the normal control group and 71 (40.6%) patients of the CAD group were positive of H. pylori infection, yet there was no statistical difference. We angiographically followed up the 80 patients of the CAD group who were treated by percutaneous coronary intervention (PCI) at 6 to 9 months after their primary intervention. Twenty two (37.9%) of the 58 patients of the H. pylori negative group and 10 (45.5%) of the 22 patients of the H. pylori positive group were treated with reintervention, but reintervention was also not significantly different between the group with H. pylori infection and the group without the infection. CONCLUSIONS These data indicated that H. pylori infection had a modest influence on CAD and progressive atheroma, but the showed a tendency to increase. Further studies are needed to evaluate the relationship between H. pylori infection and CAD.
-
4.
Response of blood endothelin-1 and nitric oxide activity in duodenal ulcer patients undergoing Helicobacter pylori eradication.
Chang, FY, Chen, CY, Lu, CL, Luo, JC, Lu, RH, Lee, SD
World journal of gastroenterology. 2005;(7):1048-51
Abstract
AIM: To investigate the effect of Helicobacter pylori eradication on endothelin-1 (ET-1) and nitric oxide (NO) in duodenal ulcer (DU) patients. METHODS Sixty-six H pylori-infected active DU patients were consecutively enrolled to receive one-week triple therapy (rabeprazole, amoxicillin and metronidazole) and then one-month rabeprazole therapy. They were asked back to determine ulcer and H pylori status using endoscopy one month later. Thirty-seven healthy controls (H pylori +/-: 17/20) were enrolled for comparison. Blood samples were collected in each visit to measure plasma ET-1 and nitrate/nitrite levels using an enzyme immunoassay kit. RESULTS Sixty DU patients finished trial per protocol. The ulcer healing and H pylori-eradication rates were 86.7% and 83.3%, respectively. Plasma ET-1 level in DU patients was higher than that of H pylori-negative and positive controls (3.59+/-0.96 vs 0.89+/-0.54 vs 0.3+/-0.2 pg/mL, P<0.01), while nitrate/nitrite levels among them were also significantly different (8.55+/-0.71 vs 5.27+/-0.68 vs 6.39+/-0.92 mumol/L, P<0.05). H pylori eradication diminished ET-1 levels (3.64+/-0.55 vs 2.64+/-0.55 pg/mL, P<0.01) but elevated nitrate/nitrite level (8.16+/-0.84 vs 11.41+/-1.42 mumol/L, P<0.05). CONCLUSION Both plasma ET-1 and nitrate/nitrite levels increase in active DU patients. After an effective H pylori eradication, DU healing is associated with diminished blood ET-1 level and elevated nitrate/nitrite level.
-
5.
13C urea breath test (UBT) in the diagnosis of Helicobacter pylori: why does it work better with acid test meals?
Pantoflickova, D, Scott, DR, Sachs, G, Dorta, G, Blum, AL
Gut. 2003;(7):933-7
-
-
Free full text
-
Abstract
BACKGROUND Acid test meals may improve the accuracy of the (13)C urea breath test (UBT). This has been attributed to changes in gastric emptying rather than to the effects of gastric pH on Helicobacter pylori urease. AIMS To determine whether enhancement of (13)CO(2) excretion in the UBT in H pylori infected volunteers by acidification of a test meal is due to a delay in gastric emptying. METHODS Urease activity in vitro was measured in intact bacteria and in bacterial homogenates. Urease activity in vivo was assessed by means of the UBT. Eleven H pylori infected subjects underwent UBTs with neutral Ensure (pH 7.0), acidified Ensure (pH 3.0), and apple juice (pH 3.0). Gastric emptying was assessed by (13)C sodium acetate breath test. RESULTS From pH 7 to pH 3, the in vitro urease activity of intact bacteria increased sixfold. In contrast, urease activity of bacterial homogenates was inactivated by low pH. In vivo, urease activity, as measured by the UBT 20 minutes after meal ingestion, was higher with apple juice (delta (13)CO(2)=21.1; p=0.03) and acidified Ensure (delta (13)CO(2)=25.5; p=0.01) than with neutral Ensure (delta (13)CO(2)=12.5). Gastric emptying was faster with apple juice (T(max)=36.7 (8) minutes) but not with acidified Ensure (T(max)=63.3 (5) minutes; p=0.06) than with neutral Ensure (T(max)=65.0 (3) minutes; p=0.04). CONCLUSIONS The higher UBT found with acidified compared with neutral test meals was independent of the emptying rates of the test meals but may have been due to medium acidity dependent activation of intra-bacterial urease in intact H pylori.
-
6.
Prospective analysis of the association of infection with CagA bearing strains of Helicobacter pylori and coronary heart disease.
Singh, RK, McMahon, AD, Patel, H, Packard, CJ, Rathbone, BJ, Samani, NJ
Heart (British Cardiac Society). 2002;(1):43-6
-
-
Free full text
-
Abstract
OBJECTIVE To see whether it was possible to replicate in a prospective study the association recently reported between infection with the more virulent (type 1) cytotoxin associated gene A (CagA) antigen carrying strains of Helicobacter pylori and increased risk of coronary heart disease. DESIGN AND SETTING Nested case-control study in a clinical outcomes trial. SUBJECTS Participants in the West of Scotland coronary prevention study. METHODS H pylori CagA serological status was determined in plasma samples of 201 subjects (cases) who subsequently had a coronary event during follow up and in 414 subjects (controls) matched for age and smoking who remained event-free, using a semiquantitative commercial enzyme linked immunosorbent assay (ELISA) kit against the p120 antigen of CagA. RESULTS 105 (52%) in the case group and 176 (43%) in the control group were seropositive (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.06 to 2.10, p = 0.022). The association remained significant after adjustment for blood pressure, body mass index, plasma concentrations of low density lipoprotein and high density lipoprotein cholesterol, history of hypertension and diabetes, statin treatment, and socioeconomic status (OR 1.51, 95% CI 1.06 to 2.16, p = 0.023). Baseline inflammatory markers (white cell count, C reactive protein, fibrinogen) were not significantly increased in either H pylori CagA positive cases or controls. CONCLUSIONS The findings provide support from a prospective study for the hypothesis that there is an association between infection with CagA bearing strains of H pylori and coronary heart disease. The mechanism(s) underlying the association remain to be elucidated.