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Biomedical subjects

Y Niv

Publications and source records attributed to Y Niv.

At least 37 records · Page 2Linked to original sources
PubMed2002

Association between gastric acid and mucin secretion in dyspeptic patients.

BACKGROUND AND AIMS: The maintenance of an intact gastric mucosa implies a balance between aggressive, such as acid, and protective factors such as mucin. We examined gastric aspirates to determine a possible correlation between gastric acid and mucin contents. METHODS: Gastric contents were aspirated at gastroscopy in 14 patients. Acid content was evaluated by titration, and mucin content by gel filtration. In 4 other patients these measurements were also performed for 1-hour basal gastric secretion, and after pentagastrin stimulation. Western blot and dot blot for mucin protein were performed with polyclonal antibodies to the protein of MUC 5AC and MUC 6. RESULTS: A positive correlation was demonstrated between acid and mucin content in 14 patients, r = 0.77. In 4 other patients mucin secretion, after pentagastrin injection, increased by 3-46 fold in comparison with basal secretion. A positive correlation was demonstrated between basal acid and mucin secretion, and stimulated acid and mucin secretion. In dot blot experiments, MUC 5AC had a significant higher dot blot intensity than MUC 6. CONCLUSIONS: There is a correlation between acid and mucin secretion rates. Secretagogue that causes acid secretion may also cause secretion of protective mucin.

Aged↗
PubMed2001

Effects of current cigarette smoking on clinical course of Crohn's disease and ulcerative colitis.

Cigarette smoking worsens Crohn's disease (CD) but ameliorates ulcerative colitis (UC). In Israel, where there is no epidemiological association of smoking with CD, we examined the effects of current smoking on the course of CD and UC. Patients at nine public hospitals completed a questionnaire detailing their smoking history, disease course and treatments; subjects altering their smoking habit after the onset of disease were excluded. Sixty-four smokers and 144 nonsmokers had CD, and 34 smokers and 158 nonsmokers had UC. No differences were found between CD smokers and nonsmokers for hospitalizations, operations, and requirement for corticosteroid and immunosuppressive treatment. By contrast, UC smokers had less extensive disease than nonsmokers (P < 0.02) and fewer hospitalizations (P = 0.01) and operations (P = 0.025). Our results agree with a minority of studies showing no adverse effect of smoking on the course of CD, and confirm the protective effect of smoking in UC.

Adolescent↗
PubMed2001

Evaluation of a novel continuous real time (13)C urea breath analyser for Helicobacter pylori.

AIM: To evaluate the sensitivity and specificity of a new (13)C urea breath test, Oridion BreathID, for the diagnosis of Helicobacter pylori. METHODS: A total of 97 consecutive symptomatic patients referred for upper endoscopy were included in the 'pre-therapy' part of the study. After endoscopy the patients were analysed for H. pylori by Oridion BreathID. BreathID continuously sampled the subject's breath for 20 min, and displayed the results on the BreathID screen in real time. Results of the BreathID were compared with the 'gold standard' (rapid urease test and histology). We also prospectively tested the validity of BreathID in comparison to isotope ratio mass spectrometry, in 40 patients referred to monitor the efficacy of H. pylori eradication treatment. RESULTS: Complete agreement was observed between the 'gold standard' and the Breath ID test in 96.9% (94 out of 97) of the patients. The sensitivity and specificity of BreathID were 97.8% and 96.1%, respectively. The correlation between BreathID and isotope ratio mass spectrometry breath test was 100%. CONCLUSIONS: The Oridion BreathID has comparable sensitivity and specificity to the claims of the currently available urea breath tests. Furthermore, BreathID has the potential advantages of ease of use with minimal medical staff requirement, and real time rapid results (20 min maximum) which may make the BreathID preferable to other urea breath test assays.

Adult↗
PubMed2001

Gastric corpus mucin expression after partial gastrectomy, in relation to colonization with Helicobacter pylori.

Twelve different genes for mucin have been described. MUC5AC and MUC6 encode the secreted apomucins of the stomach. A gradient from the surface epithelium (foveola) to the glands is typical for MUC5AC synthesis, whereas a gradient in the opposite direction was found for MUC6. Our goal was to determine the distribution of MUC5AC and MUC6 in the postoperative stomach, with relation to the H. pylori status. Gastric corpus biopsy specimens from patients who underwent partial gastrectomy were examined by immunohistochemistry for mucin gene (MUC5AC and MUC6) apoproteins. We used polyclonal antibodies for amino acid tandem repeats of both proteins. A scoring system (0-3) was used to assess staining intensity at four sites: the lumen, the foveola, the mucous neck cells, and the glands. Helicobacter pylori status was determined by histology and rapid urease test and was considered positive or negative when both tests were positive or negative, respectively. We studied 19 H. pylori-positive and 32 H. pylori-negative patients. No significant change in MUC5AC or MUC6 synthesis and secretion was demonstrated between H. pylori-positive or -negative patients. A gradient similar to that shown for the intact stomach (from the surface epithelium to the glands) for MUC5AC protein and an increase of MUC6 protein presentation from the mucous neck cell to the glands were demonstrated. The pattern of MUC5AC protein synthesis was not different between H. pylori-positive and -negative patients in the postoperative stomach. MUC6 expression was higher in the foveola in H. pylori-positive patients, whereas there was no difference in the other cell layers.

Gastrectomy↗
PubMed2001

Does Helicobacter pylori affect gastric mucin expression? Relationship between gastric antral mucin expression and H. pylori colonization.

BACKGROUND/OBJECTIVE: Helicobacter pylori colonizes the gastric mucous gel layer, the surface epithelium and glands. It has been shown that H. pylori infection causes aberrant expression of gastric mucins MUC 5 and MUC 6. This study aimed to determine the distribution of MUC 5 and MUC 6 in the gastric antrum of dyspeptic patients, and to investigate changes in this pattern in the presence of H. pylori and after successful eradication. MATERIALS AND METHODS: Gastric antrum biopsy specimens were examined by immunohistochemistry for mucin gene (MUC 5 and MUC 6) expression. Polyclonal antibodies were used to detect amino acid tandem repeats of each protein. A scoring system (0-3) was used to assess staining intensity at three sites: foveola, mucous neck cells and glands. H. pylori status was determined by histology and rapid urease test, and considered positive or negative when both tests were positive or negative, respectively. The study included 49 patients positive for H. pylori, in 36 of whom successful eradication was performed, and 11 H. pylori-negative patients. RESULTS: There was a gradient of MUC 5 expression, higher to lower, from the surface to the glands, which was more pronounced before eradication. Increased MUC 5 synthesis in the mucous neck cells and in the glands was found after H. pylori eradication (P = 0.016). MUC 6 was synthesized in the glands more than in the mucous neck cells or foveola. MUC 6 was also secreted into the lumen and probably comprised the superficial part of the unstirred mucous layer. CONCLUSION: The change in MUC 5 synthesis may reflect H. pylori colonization.

Adult↗
PubMed2001

Appendectomy is more frequent but not a risk factor in Crohn's disease while being protective in ulcerative colitis: a comparison of surgical procedures in inflammatory bowel disease.

OBJECTIVE: Appendectomy was shown to be protective in patients with ulcerative colitis (UC). There are fewer data in Crohn's disease (CD). Other operations were less studied. The aim of this study was to investigate the prevalence of appendectomy, cholecystectomy, and tonsillectomy, including their timing, in patients with inflammatory bowel disease in comparison to controls. METHODS: Two hundred seventy-one patients with UC and 260 with CD, 475 clinic controls, and 428 community controls were interviewed. RESULTS: Appendectomy was found in 5.5% patients with UC, in 11% of clinic controls (p < 0.05), and 7.7% of community controls (p = not significant). The differences were more significant for appendectomy before onset of disease. Appendectomy was performed in 19.2% of patients with CD, in 10.9% of clinic controls, and in 10.1% of community controls (p < 0.01). However, there were no significant differences when only appendectomy before onset of disease was considered. Cholecystectomy was found in 1.5% of patients with UC, in 6.1% of clinic controls (p < 0.01), and in 4.5% of community controls (p = not significant). The difference remained significant when confined to operations performed before disease onset. No such difference was found in patients with CD. No significant difference was found in the prevalence of tonsillectomy between patients and controls. CONCLUSIONS: Appendectomy is protective in UC; it is more frequent, but not a risk factor in CD. The role of cholecystectomy should be investigated further.

Adult↗
PubMed2001

A patient education program is cost-effective for preventing failure of endoscopic procedures in a gastroenterology department.

OBJECTIVE: The growing use and complexity of endoscopy procedures in GI units has increased the need for good patient preparation. Earlier studies in this area have focused on the psychological benefits of patient education programs. The present study was directed at determining cost-effectiveness of a patient education program. METHODS: A prospective, randomized, controlled design was used. The patient population consisted of 142 patients aged 18-90 yr referred for an endoscopy procedure. Ninety-one (64%) participated in a targeted educational session conducted by a dedicated departmental nurse (group 1), 38 (27%) did not (group 2), and 13 (9%) received telephonic instruction (group 3). Before the endoscopy, all patients completed a questionnaire covering background data, endoscopy-related variables, anxiety level, and satisfaction. Patient cooperation and success/failure of the procedure were documented by the attending nurse. RESULTS: Male gender, previous endoscopy, and explanation from the referring physician were associated with a low level of anxiety (p < 0.05). There was a significant association between attendance in the education program and success of the endoscopy (p = 0.0009). Cancellations of procedures because of poor preparation occurred in 4.39% of group 1 in comparison with 26.31% and 15.38% of groups 2 and 3, respectively (p = 0.005). The overall cost of the procedure was reduced by 8.6%, 8.9%, and 5.5% for gastroscopy, colonoscopy, and sigmoidoscopy, respectively. All participants expressed satisfaction with the brochure. CONCLUSION: A pre-endoscopy patient education program apparently increase patient compliance, thereby decreasing both the need for repeated examinations and their attendant costs.

Adolescent↗
PubMed2001

Relationship between Helicobacter pylori CagA status and colorectal cancer.

OBJECTIVES: Infection with Helicobacter pylori, particularly with strains positive for CagA protein, increases the risk of gastric adenocarcinoma. Few studies have explored the possible association between H. pylori infection and colorectal cancer. This study evaluated whether the seroprevalence of CagA in H. pylori-infected patients affected risk for colorectal cancer independently of H. pylori status. METHODS: In this study, we tested serum IgG antibodies against H. pylori (ELISA) and CagA protein (Western blot assay) in 67 patients with colorectal adenocarcinoma, 36 with gastric adenocarcinoma, 47 with other malignancies (cancer controls), and 45 hospitalized for transesophageal echocardiography (TEE controls). Colonic cancer and gastric cancer patients with H. pylori infection were compared to each control group and to the pooled controls using simple and adjusted analyses. RESULTS: H. pylori infection was noted in 50 colon cancer patients, 31 gastric cancer patients, 31 cancer controls, and 32 TEE controls. In all, 41 (82%), 29 (94%), 11 (35%), and 13 (41%), respectively, of these H. pylori-positive sera expressed CagA reactivity (p < 0.001 for all pairwise comparisons between cases and controls). In the adjusted analysis, infection with H. pylori CagA+ compared to H. pylori CagA- was associated with increased risk for colorectal adenocarcinoma (odds ratio = 10.6; 95% CI = 2.7-41.3; p = 0.001) and gastric adenocarcinoma (odds ratio = 88.1; 95% CI = 6.3-1229.2; p = 0.001). CONCLUSIONS: Among patients infected with H. pylori, CagA+ seropositivity is associated with increased risk for both gastric and colonic cancer. This finding should stimulate additional research into the role of cagA+ H. pylori infection in the development of colorectal cancer.

Antibodies, Bacterial↗
PubMed2001

Abolition of pentagastrin-stimulated alkaline tide using the carbonic anhydrase inhibitor acetazolamide.

BACKGROUND: Alkaline tide is the transient increase in blood and urine pH following stimulation of gastric acid secretion. It is attributed to HCO3- release from parietal cells in parallel with H+ secretion. The enzyme carbonic anhydrase is thought to be responsible for HCO3- production from CO2 and OH- in the parietal cell. OBJECTIVE: To examine the effect of pretreatment with the carbonic anhydrase inhibitor, acetazolamide, on the alkaline tide phenomenon. METHODS: Ten patients with dyspepsia and demonstrable alkaline tide were tested on three separate days. The pH and base excess were determined in arterialized venous blood before and 45 minutes after an intramuscular injection of pentagastrin. The pH of the urine was measured before and 120 min after pentagastrin injection. Measurements were performed after pentagastrin alone on day 1, following pretreatment with acetazolamide 60 min before pentagastrin on day 2, and after the administration of acetazolamide alone on day 3. RESULTS: Following the administration of pentagastrin alone, the blood base excess increased by 1.61 +/- 0.2 mEq/L (mean +/- standard deviation) and the calculated alkaline tide at 45 min was 33.99 +/- 4.49 mEq. On day 2 with prior administration of acetazolamide, base excess decreased by 0.21 +/- 0.39 mEq/L, and the calculated alkaline tide was -3.28 +/- 7.57 mEq, which was significantly lower than on day 1 (P = 0.0001). On day 3, following acetazolamide alone, the base excess values decreased by 0.53 +/- 0.2 mEq/L and the alkaline tide was -10.05 +/- 3.33 mEq; there was no significant difference compared with day 2 (P = 0.44). CONCLUSION: Pretreatment with acetazolamide abolished the alkaline tide induced by pentagastrin. This finding supports the view that carbonic anhydrase has a major role in the alkaline tide phenomenon.

Acetazolamide↗
PubMed2000

Pernicious anemia, gastric carcinoid, and autoimmune thrombocytopenia in a young woman.

The association between gastric carcinoid tumors and pernicious anemia is well recognized. Such tumors occur in the presence of achlorhydria, chronic atrophic gastritis, hypergastrinemia, and enterochromaffin-like cell hyperplasia. In this case report, a 29-year-old woman with pernicious anemia and autoimmune thrombocytopenia who developed gastric carcinoid tumors of the gastric body is described. This is the second description of pernicious anemia associated with autoimmune thrombocytopenia. This association in a young woman together with the therapeutic options and decisions that were taken in the treatment of the patient are discussed.

Adult↗
PubMed2000

Passive smoking in patients with inflammatory bowel disease: an Israeli multicentre case-control study.

BACKGROUND: The association between smoking and inflammatory bowel disease (IBD) is well established. There are, however, no large scale studies of passive smoking in inflammatory bowel disease and this has never been surveyed in the Jewish population of Israel. AIM: To study the passive smoking exposure of Jewish IBD patients in Israel in a large scale multicentre study. METHODS: Patients with established IBD, aged 18-70 years, were interviewed regarding smoking and other habits. Two controls, one clinic and one neighbourhood, matched by age, sex, community group, and education, were sought for each subject. RESULTS: Five hundred and thirty-four patients (273 ulcerative colitis (UC) and 261 Crohn's disease (CD)), 478 clinic controls and 430 community controls were interviewed. There were no significant differences in the passive smoking habits between IBD patients and their controls. Fifty-one percent of UC patients, 50% of the clinic controls and 58% of the community controls were exposed to passive smoking at home (NS); similar results were found among CD patients (50%, 55% and 56%, respectively). When a quantitative exposure index was used UC patients were significantly less exposed to passive smoking than were their community controls (7.46 +/- 8.40 vs 9.36 +/- 9.46, n = 229, P< 0.031). There was no difference in the exposure to passive smoking among CD patients and their controls. No differences in exposure to passive smoking were found when UC patients who had never smoked were compared with their controls. When the quantitative index was used 'never-smoked' CD patients tended to be less exposed to passive smoking at home than their community controls (5.40 +/- 7.60 vs 8.04 +/- 8.72, P < 0.05). CONCLUSION: There is a lack of association between passive smoking and IBD in Jewish patients in Israel. When a quantitative exposure index was used UC patients were found to be less exposed to passive smoking than their community controls.

Adolescent↗
PubMed2000

Percutaneous endoscopic gastrostomy: high mortality rates in hospitalized patients.

OBJECTIVE: Percutaneous endoscopic gastrostomy (PEG) is a widely used method for insertion of a gastrostomy tube in patients who are unable to eat but have a normally functioning gut. Complications have been described, especially in fragile, debilitated patients, and 30-day mortality rates of 4.1-26% have been reported. We assessed the outcome of PEG tube placement for inpatients and outpatients, based on morbidity, mortality, and long-term survival. METHODS: We reviewed the medical records of all patients who underwent PEG at our institution between January 1, 1995 and December 31, 1996. Four groups of patients were compared: Group 1, patients from nursing homes; Group 2, hospitalized patients; Group 3, hospitalized patients matched to Group 2 for diseases, except mental disorder, and not treated with PEG; and Group 4, the general hospital population matched for age. RESULTS: A total of 114 PEG tubes were inserted in 114 patients, 47 from Group 1, 67 from Group 2. Eighty-seven percent of patients in Group 1 underwent PEG because of dementia, versus 46% of Group 2 (p<0.001). The mortality rate was five times higher in Group 2 than in Group 3 (p<0.001). The 30-day mortality was seven times higher in Group 2 than in Group 1, twice that in Group 3, and five times higher than in Group 4 (p = 0.002 and p<0.001, respectively). When intention-to-treat analyses were applied to the data, 19/48 patients died (39.5%) in Group 1, and 60/83 (72.0%) died in Group 2, (p<0.001). CONCLUSIONS: Patients hospitalized with acute illness are at high risk for serious adverse events after PEG insertion and this procedure should be avoided.

Aged↗
PubMed2000

Lack of association between smoking and Crohn's disease but the usual association with ulcerative colitis in Jewish patients in Israel: a multicenter study.

OBJECTIVE: The association between smoking and inflammatory bowel disease (IBD) is well established, but data in Jewish patients in Israel were discrepant. The aim of this study was to examine the smoking habits of Jewish IBD patients in Israel in a large scale, multicenter study. METHODS: Patients with established IBD aged 18-70 yr were interviewed in relation to smoking and other habits. Two controls (one clinic and one neighborhood control matched by age, sex, community group, and education) were sought for each subject. RESULTS: A total of 534 patients (273 ulcerative colitis [UC], and 261 Crohn's disease [CD]), along with 478 clinic controls and 430 neighborhood controls, were interviewed. There was no significant difference in the smoking habits between CD patients and their controls. Of patients with CD, 24.5% were current smokers, as compared to 19.9% of clinic controls and 25.2% of neighborhood controls (NS). The odds ratio for CD in current smokers was 1.30 (95% confidence interval 0.85-1.99) versus clinic controls, and 0.96 (0.63-1.46) versus neighborhood controls. There were also no significant differences in the proportion of ex-smokers between the groups. Only 12.9% of UC patients were current smokers versus 21.9. % Clinic controls, and 26.4% community controls (p<0.005). The proportions of ex-smokers were higher in UC patients 29.7% versus 25.9%, and 19.5% in their respective controls (p<0.001 vs. community controls). No significant differences were found in the proportions of never-smokers between IBD patients and controls. All the above trends were similar in four different parts of the country. The proportion of current smokers in UC decreased with the extent of disease (19.7% in proctitis, 13.6% in left-sided, and 4.5% in total colitis) (p<0.05). Patients with UC were more likely to be light smokers(1-10 cigarettes/day), whereas patients with CD were more likely to be moderate smokers (11-20 cigarettes/day) in comparison to their controls. CONCLUSIONS: The lack of association between smoking and CD has now been established in Jewish patients in Israel. The association was found in UC. The stronger genetic tendency in CD may contribute to this discrepancy.

Adolescent↗