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Background H. pylori strains with different genetic contents may infect different or an individual human host. Genetic diversity of cagA is thought to contribute to differences in H. pylori strains pathogenicity. In this study, diversity of cagA genotype, EPIYA motif and copy number was assessed in H. pylori single colonies isolated from individual patients. Materials and methods Gastric biopsies from 14H. pylori-positive dyspeptic patients were cultured on selective brucella blood agar and incubated at 37 °C under microaerobic conditions. Four single colonies were obtained from each biopsy subculture on brucella blood agar under similar incubation condition. Presence of cagA and types of EPIYA motifs was determined by polymerase chain reaction (PCR) and cagA copy number by quantitative real-time (RT) PCR. Results Single colonies of 5 patients showed no variation in cagA genotype, EPIYA motif and copy number. Out of the remaining 9 patients, 1 patient showed presence or absence of cagA gene, 2 patients had mixed EPIYA motifs, 2 patients had different cagA copy number, 1 patient showed absence or presence of cagA and mixed motifs, 2 patients had cagA genes with different nucleotide sequences, 1 patient showed presence or absence of cagA and difference in cagA nucleotide sequence. Four isolates that contained multiple copies of cagA, carried EPIYA-ABC motif. Conclusion Genetic diversity of cagA among single colonies isolated from individual patients represents evidence that gastric mucosa of every individual is colonized with a specific and heterogeneous population of H. pylori. Future studies on patients in different disease groups may elucidate the role of mixed populations of H. pylori in development of gastric diseases.

With the increasing prevalence of obesity, non-alcoholic fatty liver disease (NAFLD), has become a frequent cause of chronic liver disease, often leading to cirrhosis. In recent decades, gut microbiota have been evaluated as an effective factor in NAFLD pathogenesis, causing steatohepatitis by involving the host immune system. The aim of this study is to evaluate gut microbiota dysbiosis in NAFLD/NASH patients in comparison to healthy controls.We conducted a systematic search of published studies that have examined the composition of gut microbiota in relation to NAFLD. PubMed, Scopus and ISI Web of Science were searched. After the exclusion of irrelevant studies, 15 eligible studies were included and summarized.Overall, some studies reported the composition of microbiota at the phyla level, while others reported them at smaller subgroups; the results of studies were contradictory in some cases.Overall, study findings indicate a relationship between microbial composition and NAFLD. Study methods and sequencing techniques influenced these results.

To evaluate the efficacy of Pistacia atlantica Desf. oleoresin essential oil on peptic ulcer (PU) and its antibacterial effect on metronidazole-resistant Helicobacter pylori, as well as chemical composition of the essential oil.The essential oil was standardized using gas chromatography mass spectrometry (GC/MS) analysis. Acute toxicity of the essential oil was assessed in animal model. In vitro anti-Helicobacter pylori activity was performed through disc diffusion and minimum inhibitory concentration method. For gastroprotective assay, rats received Pistacia atlantica Desf. essential oil (25, 50 and 100 mg/kg orally) 1 h before induction of ulcer by ethanol. Macroscopic (ulcer index and protection rate) and microscopic examination were performed.The GC/MS analysis of the essential oil led to the identification of twenty constituents and α-pinene is predominant constituent. The essential oil was safe up to 2000 mg/kg. All Helicobacter pylori strains were susceptible to the essential oil and the MIC ranged from 275 to 1100 μg/mL. The ulcer index for treated groups was significantly reduced compared to control (P0.001) with EC(50) value of 12.32 mg/kg. In microscopic examination, Pistacia atlantica attenuated destruction and necrosis of gastric tissue.Current study exhibited protective effect of standardized Pistacia atlantica essential oil against ethanol-induced gastric ulcer and its antibacterial activity on Helicobacter pylori. α-pinene might be the responsible agent.

Vacuole of eukaryotic cells, beyond intracellular digestion plays additional roles such as storage of nutrients that provide favorable conditions for bacterial survival. In this study, occurrence of H. pylori inside the vacuole of Candida yeast was studied and the role of vacuolating cytotoxin A (VacA) in constructing the vacuole was discussed. One gastric Candida yeast was used for Live/Dead stain and fluorescence in situ hybridization (FISH) with universal bacterial probe. Yeast total DNA was used for amplification of full-length bacterial 16S rDNA as well as H. pylori-specific 16S rDNA and vacA alleles. Vacuoles were isolated from yeast cells and stained with fluorescent yeast vacuole membrane marker MDY-64. DNA extracted from vacuoles was used for amplification of H. pylori-specific 16S rDNA. Fluorescent microscopy showed occurrence of viable bacteria inside the vacuole of intact Candida yeast cells. FISH showed intracellular bacteria as fluorescent spots inside the vacuole of mother and daughter yeast cells, suggesting bacterial transmission to next generations of yeast. Sequencing of amplified products of bacterial 16S rDNA and amplification of H. pylori 16S rDNA and vacA confirmed the identity of intracellular bacteria as H. pylori. Isolated vacuoles were stained with membrane-specific marker and H. pylori 16S rDNA was amplified from their DNA content. Results of this study suggest yeast vacuole as a specialized niche for H. pylori. It appears that sequestration inside the vacuole may enhance bacterial survival.

Helicobacter pylori might become highly resistant to antibiotics taken through the life time of patients. This study examined the change in antibiotic resistance of H. pylori by time.Out of 985 dyspeptic patients who were referred to the endoscopy unit of Shariati hospital during 2010-2017, 218 patients with gastric biopsies positive for rapid urease test (RUT) and H. pylori culture were recruited in the study. H. pylori isolates were examined for resistance to 8 currently used antibiotics by the disc diffusion method. Results were compared with those from our three previous studies. The frequency of multidrug resistance (MDR) was also assessed.The highest resistance rate was to metronidazole (MTZ) (79.4%) followed by ofloxacin (OFX) (58.7%), ciprofloxacin (CIP) (46.8%), levofloxacin (LVX) (45%), tetracycline (TET) (38.5%), clarithromycin (CLR) (34.4%), amoxicillin (AMX) (27.1%) and furazolidone (FRZ) (23.9%). No significant difference was found between resistance of H. pylori isolates from male and female40 and40 years old and patients with gastritis and peptic ulcer. The highest rates of MDR were to MTZ+OFX (4.6%), MTZ+OFX+TET (2.8%), MTZ+OFX+CIP+LVX (6.4%) and MTZ+OFX+TET+ CIP+LVX (5%).Resistance to MTZ increased from 33%-55.6% in previous studies to 79.4% by time, to CLR increased from 1.4-7.3% to 34.4%, to TET increased from 0-38.1% to 38.5%, to AMX increased from 1.4%-7.3% to 27.1% and to FRZ increased from 0%-4.5% to 23.9%. Resistance to FQs was 45%-58.7%. Increase in H. pylori antibiotic resistance indicates antibiotic misuse. In Iran, with a considerable number of H. pylori- infected patients, antibiotic therapy should be saved for high risk patients and according to local antibiotic resistance patterns.

Background Proton-pump inhibitor (PPI) consumption does lead to false-negative results of Helicobacter pylori diagnostic tests such as biopsy culture and rapid urease test (RUT). Materials and Methods Helicobacter pylori isolates from 112 dyspeptic patients with (56.5%) or without (43.5%) PPI consumption were recruited for examining the negative effects of omeprazole (OMP), lansoprazole (LPZ), and pantoprazole (PAN) on H. pylori viability, morphology, and urease, in vitro. The effect of a sublethal concentration of OMP on bacterial features and their recovery after removal of OMP was also assessed. Results Of 112 culture-positive gastric biopsies, 87.5% were RUT positive and 12.5% RUT negative. There was a significant correlation between negative RUT results and PPI consumption (p

Despite the rich literature on GERD, its cause and reason for increased prevalence remain obscure. Currently accepted mechanisms leave many questions unanswered. Nitrite chemistry at the GEJ is well described for carcinogenesis. Recent epidemiological and animal data have linked nitrates to GERD. “Nitrate reductase” of oral bacteria converts nitrates to nitrites. We hypothesized that nitrate reductase activity is higher in patients with erosive GERD, delivering more nitrite at the gastroesophageal-junction for a given nitrate intake. To compare oral nitrate reductase activity of erosive GERD patients with controls. Patients with erosive GERD and controls without GERD were enrolled. After overnight fasting, nitrite of oral cavity contents was measured at 1-min intervals for 3 min while incubating a 10-mg nitrate-N/L solution in the mouth. Nitrate reductase activity was calculated and compared between groups. Eleven cases (ten males, mean age: 42.6 ± 11.7 year) and ten controls (eight males, mean age: 37.6 ± 9.2 year) were enrolled. Mean nitrate reductase activity was 3.23 ± 0.99 vs. 2.30 ± 0.83 “μg nitrite-N formed/person/minute” in cases and controls, respectively (p = 0.03). Oral nitrate reductase activity in erosive GERD patients is higher than controls. Therefore, any dietary nitrate load generates more nitrite in these patients. This excess nitrite at the gastroesophageal junction, may potentially contribute to the development of GERD. This is the first report linking oral nitrite production to erosive GERD in man. We suggest that a “nitrate hypothesis” may answer yet unanswered questions about GERD pathogenesis. If confirmed, it may change our understanding of mechanisms of GERD and provide novel therapeutic targets.

Human gastric epithelium and immunocytes have been recognized as the sole specialized eukaryotic cells that host Helicobacter pylori (H. pylori). The aim of this study was to provide further evidence for our previous proposal regarding the occurrence of H.pylori inside the yeast vacuole, verifying the viability of the intravacuolar H.pylori by western blotting.Light microscopy and polymerase chain reaction (PCR) were used for primary detection of nonculturable H.pylori in 11 Candida yeasts (six oral and five gastric). Boiling was used for extraction of proteins from yeasts and the control H.pylori. Western blot analysis was recruited to assess the occurrence of H.pylori-specific proteins in protein pool of yeasts, using IgY-Hp raised in hens and IgG1-Hp raised in mice.The fast-moving bacterium-like bodies (BLBs) were identified as H.pylori by amplification of H.pylori 16S rRNA, ureAB, vacA s1, and ahpC genes from the whole DNA of yeasts. Analysis of the sequenced products of 16S rRNA gene amplified from the yeast and H.pylori isolates of patient #2 showed 100 % homology with the corresponding sequences of the reference H. pylori strains in GenBank. According to published data, it was plausible to assign the H.pylori-specific proteins, detected by western blot analysis, as thiol peroxidase (21 kDa), peroxiredoxin (AhpC) (26 kDa), urease-A subunit (UreA) (32 kDa), vacuolating cytotoxin A (VacA) small subunit (36 kDa), and VacA large subunit (56 kDa).Results of this study show that inside yeast, H.pylori expresses proteins and is viable. These proteins appear to serve as powerful tools to help H.pylori to establish in the vacuole of yeast where it can reach nutrients and multiply. The intimate relationship between H.pylori and Candida yeast which began long time ago, could have led to the establishment of H.pylori inside the yeast vacuole before invading human cells.

Oral cavity has been proposed as an important reservoir of H.pylori, being implicated in bacterial transmission through oral-oral route. However, some investigators believe that the newborn acquires H.pylori from mother through vaginal delivery. In this study, oral and vaginal yeasts were examined for the intracellular occurrence of H.pylori and their possible role in bacterial transmission. Sixty nine oral and vaginal yeasts from expecting mothers (39 oral and 30 vaginal) and seven oral yeasts from neonates(6/46 vaginal delivery, 1/43 cesarean) were identified and studied by light and fluorescent microscopy for observing the intracellular bacterium-like bodies(BLBs). Whole DNAs of yeasts were recruited for detection of H.pylori-specific genes. Urea breath test (UBT) was performed for detection of H.pylori infection in mothers. Stool antigen test (SAT) was used for detection of H.pylori antigens in infants' stool at birth and six months of age. Oral yeasts were isolated more frequently from normally-delivered neonates. The frequency of H.pylori genes in mothers' vaginal yeasts was significantly higher than in mothers' oral yeasts. A significant correlation was found between the occurrence of H.pylori genes in vaginal yeasts and that in neonates' oral yeasts, occurrence of H.pylori genes in mothers' vaginal yeasts or neonates' oral yeasts, and UBT+ results in mothers.C.albicans which colonizes the oral cavity of neonates through vaginal delivery or contact with environment or healthcare workers could be an important reservoir of H.pylori. Vaginal yeasts are more potent in accommodating H.pylori than oral yeasts. Accordingly, vaginal yeast is proposed as the primary reservoir of H.pylori which facilitates H.pylori transmission to neonates.

Non-antifungal drugs appear promising in treatment of opportunistic infections of Candida spp. that are often resistant to current antifungals.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.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.Trifluoperazine could be considered as an alternative antifungal when encountering Candida spp. resistant to current antifungals.

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.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.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.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.