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Background: Non-antifungal drugs appear promising in treatment of opportunistic infections of Candida spp. that are often resistant to current antifungals. Methods: The broth macrodilution method (NCCLS M27-P document) was used to compare the antifungal activity of trifluoperazine, propranolol, and lansoprazole with that of ketoconazole and amphotericin B, using 50 yeast isolates from the GI tract. The minimum fungicidal concentrations (MFCs), resistance rates and the time required for fungicidal activity of the drugs (2--48 hours) were determined. Results: The most effective antifungal activity was exhibited by trifluoperazine. Its MFC was 32 µg/mL for Candida albicans (3.3% resistance) and Candida spp. (0% resistance) yeasts, and 64 µg/mL for Candida tropicalis with 10% resistance. The MFC for C. albicans and Candida spp. was comparable to that of ketoconazole. However, the time required for the inhibitory effect (6 hr) was shorter than that of ketoconazole (48 hr) or amphotericin B (24 hr). The time required for the inhibitory activity on C. tropicalis was 24 hr, which was shorter than that of ketoconazole and amphotericin B (48 hr). A considerable number (40%) of Candida spp. showed resistance to ketoconazole, and 20% of C. tropicalis showed resistance to amphotericin B. Trifluoperazine, an antipsychotic drug, exhibited effective antifungal activity with the MFC, comparable to ketoconazole (32 µg/mL). Among the three yeast groups, C. tropicalis showed resistance to trifluoperazine and amphotericin B, and Candida spp. was considerably resistant to ketoconazole. Conclusion: Trifluoperazine could be considered as an alternative antifungal when encountering Candida spp. resistant to current antifungals. [ABSTRACT FROM AUTHOR]

Antimicrobials have been useful in the treatment of H.pylori-related dyspeptic diseases. However, emergence of resistant strains often decreases the eradication rates of H.pylori infections. Large-scale use of antimicrobials will lead to the diminishment of susceptible strains while allowing resistant survivors to outgrow and spread resistance genes. The aim of this study was to assess the change in antimicrobial resistance rate of H.pylori isolates from 2005 to 2008 and indicate the consequences of indiscriminate and widespread use of antimicrobials against H. pylori- and non-H.pylori-related infections. Methods: A total of 110 H. pylori strains were isolated from dyspeptic patients during 2005 to 2008 and tested for their susceptibility to antimicrobials using the disk diffusion method. MICs were determined for metronidazole (8 μg/mL), tetracycline (0.5 μg/mL), clarithromycin (2 μg/mL), amoxicillin (1 μg/mL) and furazolidone (0.5 μg/mL). Since the rates of resistance to metronidazole and tetracycline were remarkably high, another 50 isolates were tested for their susceptibility to metronidazole at the same MIC (8 μg/mL) and tetracycline at MICs of 0.5,1 and 2 μg/mL. Resistance rates were compared to those obtained in our two previous studies between 1997 - 2000 and 2001 - 2004. Results: The resistance rates of 110 H.pylori isolates to clarithromycin, amoxicillin and furazolidone were 7.3%, 7.3%, and 4.5%, respectively. Among 160 H.pylori isolates, 55.6% exhibited resistance to metronidazole and 38.1% to tetracycline. Discussion: Compared to our two previous studies, the resistance rates of H.pylori isolates to current antimicrobials has changed over time. The change in resistance rates of clarithromycin, amoxicillin and furazolidone was not statistically significant. However, resistance to metronidazole and tetracycline showed a considerable increase from 33 - 36.3% to 55.6% and 0 - 0.7% to 38.1%, respectively. Emergence of resistance due to the intensive use of antibiotics has become a global public health problem. It appears that plasmid-carried genes are involved in the spread of resistance traits among bacteria. Results obtained in this study indicate that the increase in resistance rates of H.pylori isolates to metronidazole and tetracycline could be the indication of indiscriminate and frequent use of antibiotics in Iran. [ABSTRACT FROM AUTHOR]

Background: Antimicrobials have been useful in the treatment of H. pylori-related dyspeptic diseases. However, emergence of resistant strains often decreases the eradication rates of H. pylori infections. Large-scale use of antimicrobials will lead to the diminishment of susceptible strains while allowing resistant survivors to outgrow and spread resistance genes. The aim of this study was to assess the change in antimicrobial resistance rate of H. pylori isolates from 2005 to 2008 and indicate the consequences of indiscriminate and widespread use of antimicrobials against H. pylori- and non-H. pylori-related infections., Methods: A total of 110 H. pylori strains were isolated from dyspeptic patients during 2005 to 2008 and tested for their susceptibility to antimicrobials using the disk diffusion method. MICs were determined for metronidazole (8 microg/mL), tetracycline (0.5 microg/mL), clarithromycin (2 microg/mL), amoxicillin (1 microg/mL) and furazolidone (0.5 microg/mL). Since the rates of resistance to metronidazole and tetracycline were remarkably high, another 50 isolates were tested for their susceptibility to metronidazole at the same MIC (8 microg/mL) and tetracycline at MICs of 0.5,1 and 2 microg/mL. Resistance rates were compared to those obtained in our two previous studies between 1997-2000 and 2001-2004., Results: The resistance rates of 110 H. pylori isolates to clarithromycin, amoxicillin and furazolidone were 7.3%, 7.3%, and 4.5%, respectively. Among 160 H. pylori isolates, 55.6% exhibited resistance to metronidazole and 38.1% to tetracycline., Discussion: Compared to our two previous studies, the resistance rates of H. pylori isolates to current antimicrobials has changed over time. The change in resistance rates of clarithromycin, amoxicillin and furazolidone was not statistically significant. However, resistance to metronidazole and tetracycline showed a considerable increase from 33-36.3% to 55.6% and 0-0.7% to 38.1%, respectively. Emergence of resistance due to the intensive use of antibiotics has become a global public health problem. It appears that plasmid-carried genes are involved in the spread of resistance traits among bacteria. Results obtained in this study indicate that the increase in resistance rates of H. pylori isolates to metronidazole and tetracycline could be the indication of indiscriminate and frequent use of antibiotics in Iran.

Stool-antigen detection kits for diagnosis of Helicobacter pylori infection have been widely used because of their full non-invasive nature. Because Helicobacter pylori strains show a distinctive genetic diversity, it is important to find a protein that is a common antigen of various strains and shows a strong immunogenicity for the development of a stool- antigen detection kit. Alkyl hydroperoxide reductase (AhpC) of Helicobacter pylori strongly reacts with the sera of patients with gastritis and peptic ulcer. Therefore, AhpC seems to be an excellent candidate as a target protein for this study. Accordingly, polyclonal antiserum against AhpC was produced in adult New Zealand white rabbits by using AhpC in the gel bands without adding Freund's adjuvant. In addition, isolation and purification of AhpC were perfomed by preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis and electroelution. In this study, a simple method was used for rapid production of polyclonal antibody against AhpC of H. pylori, which avoids both the long-term AhpC purification and the addition of Freund's adjuvant. One-dimensional preparative gel electrophoresis allows a single and short purification step; the high-resolution capacity of this technique leads to a high level of purity of the protein and consequently to a very high specificity of the antibody. Moreover, this method avoids contamination by other non-specific proteins, which often appear during the purification process by column chromatographic techniques, which may also decrease the purity of the immunogen. The present method is simple, rapid and cost-effective, and also makes it possible to produce antibody for stool-antigen enzyme immunoassay in a short time and at low cost.

Smoking has not only enormous deleterious effects on cardiovascular, cerebral, and bronchial organs but also profoundly alters the function of all parts of the gastrointestinal tract through various mechanisms. Except the sole curiously observed benefit of smoking on the course of ulcerative colitis, it increases the prevalence of the common gastrointestinal diseases namely gastroesophageal acid reflux, peptic ulcer, and Crohn's diseases. It also increases the incidence of cancer of oral cavity, esophagus, stomach, pancreas, and liver mostly in a dose-response relationship and worsens the prognosis of colon cancer. The cessation of smoking is associated with the reduced incidence of cancer in the reported organs, but its effect on the regression of benign disease is not generally studied. The physicians must be aware not only of the harmful effect of smoking on the cardiovascular and bronchial systems, but also about the detrimental consequences of life-long smoking on the gastrointestinal tract and the increase of its benign and malignant diseases.

Background: Furazolidone has been effective against Helicobacter pylori in Iran, with no resistance, but with intolerable side effects in the second week. One-week regimens have not been useful here. We compared the efficacy and side effect profiles of three anti-H. pylori regimens., Methods: Patients with peptic ulcer disease and positive H. pylori infection were randomly allocated into three groups. The patients in group A received omeprazole 20 mg + amoxicillin 1g + metronidazole 500 mg, and bismuth subcitrate 240 mg twice daily each, for two weeks; the patients in group B received the same regimen but metronidazole was replaced by furazolidone 200 mg twice daily; and the patients in group C received regimen B for the first week and regimen A for the second week. H. pylori eradication was verified with 13C-urea breath test at the tenth week., Results: Three hundred and fourteen patients were enrolled; 107, 104, and 103 patients in groups A-C, respectively but 278 patients completed the study. Seven, three, and six patients discontinued their medication in groups A-C, respectively. Fever, dizziness, and weakness were more common in group B than group C (P < 0.05). Vomiting, pruritus, and rash were more common in group C than group A (P < 0.05). Per-protocol eradication rates were 83.1%, 95.2%, and 95.3% in groups A-C, respectively (P = 0.005, groups A and C). Intention to treat eradication rates were 74.5%, 87.0%, and 86.6% in groups A-C, respectively (P = 0.02, groups A and C)., Conclusion: One-week furazolidone followed by one-week metronidazole regimen is as efficient as two-week furazolidone regimen but with fewer side effects. Furazolidone-based regimens are superior to metronidazole-based ones for H. pylori eradication in Iran.

Aim: To examine the frequency of antibiotic resistance in Iranian Helicobacter pylori (H pylori) strains isolated from two major hospitals in Tehran., Methods: Examination of antibiotic resistance was performed on 120 strains by modified disc diffusion test and PCR-RFLP methods. In addition, in order to identify the possible causes of the therapeutic failure in Iran, we also determined the resistance of these strains to the most commonly used antibiotics (metronidazole, amoxicillin, and tetracycline) by modified disc diffusion test., Results: According to modified disc diffusion test, 1.6% of the studied strains were resistant to amoxicillin, 16.7% to clarithromycin, 57.5% to metronidazole, and there was no resistance to tetracycline. Of the clarithromycin resistant strains, 73.68% had the A2143G mutation in the 23S rRNA gene, 21.05% A2142C, and 5.26% A2142G. None of the sensitive strains were positive for any of the three point mutations. Of the metronidazole resistant strains, deletion in rdxA gene was studied and detected in only 6 (5%) of the antibiogram-based resistant strains. None of the metronidazole sensitive strains possessed rdxA gene deletion., Conclusion: These data show that despite the fact that clarithromycin has not yet been introduced to the Iranian drug market as a generic drug, nearly 20% rate of resistance alerts toward the frequency of macrolide resistance strains, which may be due to the widespread prescription of erythromycin in Iran. rdxA gene inactivation, if present in Iranian H pylori strains, may be due to other genetic defects rather than gene deletion.