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T Borody

Publications and source records attributed to T Borody.

12 recordsLinked to original sources
PubMed2005

Evaluation of anti-Helicobacter pylori IgG2 antibody for the diagnosis of Helicobacter pylori infection in western and Chinese populations.

BACKGROUND: The performance of commercial Helicobacter pylori diagnostic kits developed for particular geographic regions has often been found to be of poor diagnostic value when applied to other regions, possibly because of infections being caused by different H. pylori strains in different regions. AIM: To evaluate the performance of an IgG2 anti-H. pylori enzyme-linked immunoassay test (Helirad Alert) for detection of H. pylori infection in both Australian and Hong Kong (Chinese) subjects. METHODS: Serum samples were tested for H. pylori specific IgG2 and IgG antibodies by enzyme-linked immunoassay kits using identical antigen preparation in 168 Australian and 160 Hong Kong (Chinese) subjects diagnosed with dyspepsia. RESULTS: Using a cut-off value determined by analysis of H. pylori-negative Australian samples, the sensitivity, specificity and accuracy of the IgG2 assay were 77.8, 97.4 and 91.1%, respectively, for the Australian samples and 96.3, 83.8 and 90% for Hong Kong samples. For the IgG assay, sensitivity, specificity and accuracy were 87.0, 99.1 and 95.2% for Australian samples and 97.5, 75 and 86.3% for Hong Kong samples respectively. Receiver-operating characteristic analysis showed better discrimination of H. pylori status when the IgG2 assay was applied to Hong Kong samples, while the IgG assay was better in the Australian samples. CONCLUSION: These data demonstrate that the Helirad Alert enzyme-linked immunoassay could provide a reliable method for screening H. pylori infection in both western and Chinese populations.

Adult↗
PubMed2003

Efficacy and safety of single-triple capsules of bismuth biskalcitrate, metronidazole and tetracycline, given with omeprazole, for the eradication of Helicobacter pylori: an international multicentre study.

BACKGROUND: The high prevalence of Helicobacter pylori resistance to metronidazole demands treatments more effective than standard bismuth-based triple therapy against these strains. AIM: To evaluate the H. pylori eradication rate in both metronidazole-sensitive and -resistant strains following quadruple therapy using single-triple capsules of bismuth biskalcitrate, metronidazole and tetracycline, given with omeprazole. METHODS: One hundred and seventy valid patients with duodenal ulcer, gastric ulcer or non-ulcer dyspepsia were treated in eight centres located in five countries. H. pylori was confirmed at baseline using 13C-urea breath test, histology and/or culture. Patients received three single-triple capsules q.i.d. and omeprazole, 20 mg b.d., for 10 days. Each capsule contained bismuth biskalcitrate, 140 mg (as 40 mg Bi2O3 equivalent), metronidazole, 125 mg, and tetracycline, 125 mg. 13C-Urea breath test was repeated at least 4 and 8 weeks post-treatment. RESULTS: Overall eradication rates were 93% (158/170) by modified intention-to-treat analysis and 97% (142/146) by per protocol analysis. Eradication rates were 93% (40/43) and 95% (38/40) for strains resistant to metronidazole and 95% (82/86) and 99% (75/76) for strains sensitive to metronidazole by modified intention-to-treat and per protocol analysis, respectively. CONCLUSION: This omeprazole-bismuth biskalcitrate-metronidazole-tetracycline 10-day regimen is a very effective and well-tolerated treatment, which overcomes metronidazole resistance.

Adolescent↗
PubMed2001

Shift of the gastric T-cell response in gastric carcinoma.

BACKGROUND AND AIMS: The etiology and pathophysiology of stomach carcinoma is complex, and the mechanism whereby H. pylori directly or indirectly induces carcinoma remains unclear. In this study, interleukin (IL)-8, IL-4 and interferon (IFN)-gamma were measured in the tissue culture supernatant of gastric organ cultures from subjects with chronic gastritis with or without H. pylori infection, and with or without gastric cancer and gastric dysplasia. RESULTS: Interleukin-8 levels were higher in cancer- and H. pylori-infected gastritis subjects than in H. pylori-negative subjects (12.95 +/- 3.16, 10.48 +/- 1.55 and 4.49 +/- 1.28 ng/mL, respectively). Elevated levels of IFN-gamma were detected in both H. pylori-infected and non-infected subjects with uncomplicated gastritis (72.23 +/- 19.0 and 34.61 +/- 5.30 pg/mL) and in non-infected dysplasia subjects (88 +/- 20.5 pg/mL). Background levels of IL-4 (< or = 9.4 pg/mL) in uncomplicated gastritis subjects and relatively high levels of IL-4 in dysplasia subjects (25.8 +/- 7.3 pg/mL) were detected. In contrast, trace amounts of IFN-gamma (16.01 +/- 0.35 pg/mL) and high levels of IL-4 (42.81 +/- 8.49 pg/mL) in gastric biopsy culture supernatants were found in cancer subjects. Mucosal IL-4 levels (but not IL-8 levels) correlated with infection and mucosal anti-H. pylori immunoglobulin G antibody. CONCLUSIONS: The significant differences between gastritis with and without cancer and dysplasia indicated a shift from a Th1 to a Th2 helper cell pattern of cytokine secretion. This study has identified a local mucosal defect in gastric cancer. The near absence of IFN-gamma production from the mucosa at the margins of the tumor may be a critical factor in promoting growth of neoplastic cells.

Adenocarcinoma↗
PubMed2000

Circulating T-cell response to Helicobacter pylori infection in chronic gastritis.

BACKGROUND: Helicobacter pylori elicits a specific humoral and cellular immune response. There is increasing evidence that the type of T-cell response contributes to clinical outcome in H. pylori infection. MATERIALS AND METHODS: The host response to H. pylori infection in 34 subjects with chronic gastritis was examined in terms of T-cell proliferation and cytokine production in whole-blood cultures stimulated or unstimulated with H. pylori acid-glycine extract antigens (AGE). RESULTS: The proliferative response in whole-blood cultures was similar for both H. pylori-positive and -negative subjects stimulated with H. pylori AGE. While an increase in interferon-gamma (IFN-gamma) production was observed from both H. pylori-positive and -negative subjects with gastritis, significantly higher levels of IFN-gamma were detected in the former when stimulated with H. pylori AGE. In contrast, interleukin 4 (IL-4) was undetectable regardless of antigen stimulation. However, if an in situ IL-4 antibody capture assay was used, antigen-independent production of IL-4 was detected, but there was no difference between H. pylori-positive and -negative subjects with gastritis. After eradication of H. pylori, antigen-induced production of IL-4 was increased, with no decrease in the levels of secretion of IFN-gamma. IL-4 production was dependent on CD4+ T cells, as addition of anti-CD4 but not anti-CD8 mouse monoclonal antibody or matched IgG isotype to the whole-blood culture inhibited the production of IL-4. CONCLUSION: The results suggest that a shift toward a balanced Th1-Th2 response due to an increase in antigen-induced IL-4 production from CD4+ T cells follows eradication. We suggest that the downregulation of mucosal inflammation consequent on reduction in antigen levels or removal of downregulation after eradication of H. pylori contributes to this shift in cytokine balance.

Adult↗
PubMed1998

Nizatidine in combination with amoxycillin and clarithromycin in the treatment of Helicobacter pylori infection.

BACKGROUND: The efficacy of H2-antagonists in combination with antibiotics in curing Helicobacter pylori infection remains controversial, and it is uncertain whether double dose H2-antagonist therapy is superior to standard dose. AIM: To determine the efficacy of two doses of nizatidine in combination with two antibiotics in the treatment of H. pylori. METHODS: A randomized controlled trial was conducted in 160 patients comparing nizatidine 150 mg with 300 mg b.d. (standard vs. double dose), in combination with clarithromycin (500 mg) and amoxycillin (1000 mg) b.d. for 14 days, in Australia and Taiwan. Compliance was based on a clinical assessment and pill count. H. pylori status was determined by histology (antrum and corpus) and CLO-test. RESULTS: Baseline clinical and endoscopic findings were similar in both arms of the study. Based on an intention-to-treat analysis, cure of H. pylori was achieved in 78% (95% CI: 70.4-85.4%) in the standard nizatidine dose arm and 70% (95% CI: 61.6-78.2%) in the double dose arm (P=0.2). Similar cure rates were observed in ulcer and non-ulcer patient groups. Compliance was excellent in the single and double dose arms (85 and 91%, respectively). CONCLUSIONS: The combination of nizatidine in standard or double dose with clarithromycin and amoxycillin is similarly efficacious in curing H. pylori infection.

Adult↗
PubMed1981

Radioimmunoassay of cholecystokinin in human plasma.

A sensitive radioimmunoassay for cholecystokinin (CCK) has been developed. Porcine CCK-33 was labelled by conjugation with 125I-hydroxyphenyl-propionic acid succinimide ester. Antibodies were raised against porcine CCK-33 covalently coupled to egg albumin. Plasma samples were extracted with 96% ethanol prior to assay. Free and bound hormone were separated by dextran-coated charcoal. The antibodies bound CCK-8 and CCK-33 with equimolar potency. The assay detection limit was 1 pmol/l plasma. Within and between assay coefficients of variation were +/- 12.7 and 13.0% at mean plasma CCK concentrations of 13.2 and 13.6 pmol/l. The concentration of CCK in 47 normal fasting subjects ranged from undetectable to 22 pmol/l. Ingestion of a mixed meal in 9 normal subjects increased the plasma concentration from 8.3 +/- 2.5 S.E. to 24.4 +/- 6.5 pmol/l.

Animals↗
PubMed1981

Cholecystokinin and gallbladder contraction: effect of CCK infusion.

Cholecystokinin octapeptide (CCK-8) was infused intravenously in five normal subjects. Plasma levels of CCK-8 and infusion concentrations were measured by a specific radioimmunoassay and gallbladder volumes wee monitored using ultrasound. Calculated CCK-8 infusion rates were 16.4, 32.8, and 65.6 pmol.kg(-1) hr(-1). During infusion of the lowest dose plasma concentrations rose from 8 +/- S.E. 5 to 18 +/- 4 pmol.1(-1) equivalent to normal postprandial concentrations of CCK and were accompanied by a 76 +/- 7% reduction in gallbladder volume. Infusion at the two higher rates resulted in 87 +/- 3% and 88 +/- 3% reduction of initial gallbladder volumes returned to 73 +/- 26% of initial volumes within 30 minutes. These studies are consistent with the hypothesis that CCK is the main postprandial stimulus for gall-bladder contraction.

Cholecystokinin↗
PubMed1979

Chlorbutol toxicity and dependence.

A case of chlorbutol toxicity and dependence is presented. A very long elimination half-life (13.2 days) was found in the patient. The data suggest that chlorbutol is an unsuitable sedative to be available freely to the public.

Adult↗
PubMedDate not supplied

The use of serology to diagnose active Campylobacter pylori infection.

A serological test that predicts accurately active Campylobacter pylori infection in the human stomach has been developed and validated by means of serum from 189 patients who were undergoing endoscopy in Sydney. Our enzyme-linked immunosorbent assay (ELISA) has a sensitivity of 100% and a specificity of 94%. An important part of the test is the inclusion of a simple absorption step with C. jejuni for those sera whose results are close to the cut-off point for positivity. This has been shown to be particularly relevant in epidemiological studies on populations that are likely to be exposed to C. jejuni continually. For example, by means of the ELISA test without an absorption step, the infection rate in Papua New Guineans was shown to be 56%, whereas use of the validated test showed the infection rate to be 25%. Compared with an age-matched normal control group of Australians, this still is higher. These studies suggest a need for the reappraisal of some of the reported epidemiological data. The development of a validated diagnostic test that is a highly-accurate predictor of active C. pylori infection will be useful for epidemiological studies, particularly for comparative studies among populations that are known to differ significantly in the incidence of stomach disease. However, routine use of this test in diagnosis in general practice awaits the definition of more precise markers of C. pylori-associated symptomatology and the development of improved regimens for the treatment of C. pylori infections.

Adolescent↗