Prevalence of non Helicobacter pylori species in patients presenting with dyspepsia

<p>Abstract</p> <p>Background</p> <p>Helicobacter species associated with human infection include <it>Helicobacter pylori, Helicobacter heilmannii </it>and <it>Helicobacter felis </it>among others. In this study we determined the prevalence of <it>H. pylori </it>and non-<it>Helicobacter pylori </it>organisms <it>H. felis and H. heilmannii </it>and analyzed the association between coinfection with these organisms and gastric pathology in patients presenting with dyspepsia. Biopsy specimens were obtained from patients with dyspepsia on esophagogastroduodenoscopy (EGD) for rapid urease test, histology and PCR examination for Helicobacter genus specific 16S rDNA, <it>H. pylori </it>phosphoglucosamine mutase (<it>glmM</it>) and urease B (<it>ureB</it>) gene of <it>H. heilmannii </it>and <it>H. felis</it>. Sequencing of PCR products of <it>H. heilmannii </it>and <it>H. felis </it>was done.</p> <p>Results</p> <p>Two hundred-fifty patients with dyspepsia were enrolled in the study. The mean age was 39 ± 12 years with males 162(65%). Twenty-six percent (66 out of 250) were exposed to cats or dogs. PCR for Helicobacter genus specific 16S rDNA was positive in 167/250 (67%), <it>H. pylori glmM </it>in 142/250 (57%), <it>H. heilmannii </it>in 17/250 (6%) and <it>H. felis </it>in 10/250 (4%), respectively. All the <it>H. heilmannii </it>and <it>H. felis </it>PCR positive patients were also positive for <it>H. pylori </it>PCR amplification. The occurrence of coinfection of <it>H. pylori </it>and <it>H. heilmannii </it>was 17(6%) and with <it>H. felis </it>was 10(4%), respectively. Only one out of 66 exposed to pets were positive for <it>H. heilmannii </it>and two for <it>H. felis</it>. Histopathology was carried out in 160(64%) of 250 cases. Chronic active inflammation was observed in 53(56%) (p = 0.001) of the patients with <it>H. pylori </it>infection alone as compared to 3(37%) (p = 0.73) coinfected with <it>H. heilmannii </it>and <it>H. pylori </it>and 3(60%) coinfected with <it>H. felis </it>and <it>H. pylori </it>(p = 0.66). Intestinal metaplasia was observed in 3(3%)(p = 1.0) of the patients with <it>H. pylori </it>infection alone as compared to 2(25%) (p = 0.02) coinfected with <it>H. heilmannii </it>and <it>H. pylori </it>and 1(20%) coinfected with <it>H. felis </it>and <it>H. pylori </it>(p = 0.15).</p> <p>Conclusion</p> <p>The prevalence of <it>H. heilmannii </it>and <it>H. felis </it>was low in our patients with dyspepsia. Exposure to pets did not increase the risk of <it>H. heilmannii </it>or <it>H. felis </it>infection. The coinfection of <it>H. pylori </it>with <it>H. heilmannii </it>was seen associated with intestinal metaplasia, however this need further confirmation.</p

Medicinal importance of grapefruit juice and its interaction with various drugs

Grapefruit juice is consumed widely in today's health conscious world as a protector against cardiovascular diseases and cancers. It has however, been found to be an inhibitor of the intestinal cytochrome P – 450 3A4 system, which is responsible for the first pass metabolism of many drugs. The P – glycoprotein pump, found in the brush border of the intestinal wall which transports many of these cytochrome P – 450 3A4 substrates, has also been implicated to be inhibited by grapefruit juice. By inhibiting these enzyme systems, grapefruit juice alters the pharmacokinetics of a variety of medications, leading to elevation of their serum concentrations. Most notable are its effects on the calcium channel antagonist and the statin group of drugs. In the case of many drugs, the increased serum concentration has been found to be associated with increased frequency of dose dependent adverse effects. In this review, we have discussed the phytochemistry of grapefruit juice, the various drugs involved in the drug – grapefruit juice eraction with their mechanisms of action and have presented the clinical implications of these interactions

cis-Urocanic Acid Attenuates Acute Dextran Sodium Sulphate-Induced Intestinal Inflammation

On exposure to sunlight, urocanic acid (UCA) in the skin is converted from trans to the cis form and distributed systemically where it confers systemic immunosuppression. The aim of this study was to determine if administration of cis-UCA would be effective in attenuating colitis and the possible role of IL-10. Colitis was induced in 129/SvEv mice by administering 5% dextran sodium sulfate (DSS) for 7 days in drinking water. During this period mice received daily subcutaneously injections of cis-UCA or vehicle. To examine a role for IL-10, 129/SvEv IL-10−/− mice were injected for 24 days with cis-UCA or vehicle. Clinical disease was assessed by measurement of body weight, stool consistency, and presence of blood. At sacrifice, colonic tissue was collected for histology and measurement of myeloperoxidase and cytokines. Splenocytes were analyzed for CD4+CD25+FoxP3+ T-regulatory cells via flow cytometry. Murine bone-marrow derived antigen-presenting cells were treated with lipopolysaccharide (LPS) ± UCA and cytokine secretion measured. Our results demonstrated that cis-UCA at a dose of 50 µg was effective in ameliorating DSS-induced colitis as evidenced by reduced weight loss and attenuated changes in colon weight/length. This protection was associated with reduced colonic expression of CXCL1, an increased expression of IL-17A and a significant preservation of splenic CD4+CD25+FoxP3+ T-regulatory cells. cis-UCA decreased LPS induced CXCL1, but not TNFα secretion, from antigen-presenting cells in vitro. UCA reduced colonic levels of IFNγ in IL-10−/− mice but did not attenuate colitis. In conclusion, this study demonstrates that cis-urocanic acid is effective in reducing the severity of colitis in a chemically-induced mouse model, indicating that pathways induced by ultraviolet radiation to the skin can influence distal sites of inflammation. This provides further evidence for a possible role for sunlight exposure in modulating inflammatory disorders

High power Q-switched thulium doped fibre laser using carbon nanotube polymer composite saturable absorber

We have proposed and demonstrated a Q-switched Thulium doped bre laser (TDFL) with a ‘Yin-Yang’ all- bre cavity scheme based on a combination of nonlinear optical loop mirror (NOLM) and nonlinear ampli ed loop mirror (NALM). Unidirectional lasing operation has been achieved without any intracavity isolator. By using a carbon nanotube polymer composite based saturable absorber (SA), we demonstrated the laser output power of ~197 mW and pulse energy of 1.7 μJ. To the best of our knowledge, this is the highest output power from a nanotube polymer composite SA based Q-switched Thulium doped bre laser

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data