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Sample records for pylori vacuolating toxin

  1. Helicobacter pylori vacuolating toxin A and apoptosis

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    Rassow Joachim

    2011-11-01

    Full Text Available Abstract VacA, the vacuolating cytotoxin A of Helicobacter pylori, induces apoptosis in epithelial cells of the gastic mucosa and in leukocytes. VacA is released by the bacteria as a protein of 88 kDa. At the outer surface of host cells, it binds to the sphingomyelin of lipid rafts. At least partially, binding to the cells is facilitated by different receptor proteins. VacA is internalized by a clathrin-independent mechanism and initially accumulates in GPI-anchored proteins-enriched early endosomal compartments. Together with early endosomes, VacA is distributed inside the cells. Most of the VacA is eventually contained in the membranes of vacuoles. VacA assembles in hexameric oligomers forming an anion channel of low conductivity with a preference for chloride ions. In parallel, a significant fraction of VacA can be transferred from endosomes to mitochondria in a process involving direct endosome-mitochondria juxtaposition. Inside the mitochondria, VacA accumulates in the mitochondrial inner membrane, probably forming similar chloride channels as observed in the vacuoles. Import into mitochondria is mediated by the hydrophobic N-terminus of VacA. Apoptosis is triggered by loss of the mitochondrial membrane potential, recruitment of Bax and Bak, and release of cytochrome c.

  2. Vacuolating cytotoxin A (VacA) - A multi-talented pore-forming toxin from Helicobacter pylori.

    Science.gov (United States)

    Junaid, Muhammad; Linn, Aung Khine; Javadi, Mohammad Bagher; Al-Gubare, Sarbast; Ali, Niaz; Katzenmeier, Gerd

    2016-08-01

    Helicobacter pylori is associated with severe and chronic diseases of the stomach and duodenum such as peptic ulcer, non-cardial adenocarcinoma and gastric lymphoma, making Helicobacter pylori the only bacterial pathogen which is known to cause cancer. The worldwide rate of incidence for these diseases is extremely high and it is estimated that about half of the world's population is infected with H. pylori. Among the bacterial virulence factors is the vacuolating cytotoxin A (VacA), which represents an important determinant of pathogenicity. Intensive characterization of VacA over the past years has provided insight into an ample variety of mechanisms contributing to host-pathogen interactions. The toxin is considered as an important target for ongoing research for several reasons: i) VacA displays unique features and structural properties and its mechanism of action is unrelated to any other known bacterial toxin; ii) the toxin is involved in disease progress and colonization by H. pylori of the stomach; iii) VacA is a potential and promising candidate for the inclusion as antigen in a vaccine directed against H. pylori and iv) the vacA gene is characterized by a high allelic diversity, and allelic variants contribute differently to the pathogenicity of H. pylori. Despite the accumulation of substantial data related to VacA over the past years, several aspects of VacA-related activity have been characterized only to a limited extent. The biologically most significant effect of VacA activity on host cells is the formation of membrane pores and the induction of vacuole formation. This review discusses recent findings and advances on structure-function relations of the H. pylori VacA toxin, in particular with a view to membrane channel formation, oligomerization, receptor binding and apoptosis.

  3. Effect of the Vacuolation of Helicobacter Pylori

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Cytotoxic test in vitro combined with cytochemical stain, fluorescent stain, transmission electronmicrograph was used to study the vacuolated effect by helicobacter pylori (H.pylori) (Toxin+) and its pathological mechanism. 78.26 % patients with peptic ulcer associated with H.pylori was infected with H.pylori (Toxin+), while 42.86 % patients with gastritis was infected with H.pylori (Toxin+). It was positive in vacuole with acridine orange and acid phosphatase stain. Transmission electronmicrograph of vacuole revealed the presence of abounding membrane. There was a closed relationship between infection with H.pylori (Toxin+) and peptic ulcer disease. The vacuole induced by H.pylori (Toxin+) was autophagosome, which was pathological phenomenon induced by toxin.

  4. Analysis of a β-helical region in the p55 domain of Helicobacter pylori vacuolating toxin

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    Algood Holly

    2010-02-01

    Full Text Available Abstract Background Helicobacter pylori is a gram-negative bacterium that colonizes the human stomach and contributes to the development of gastric cancer and peptic ulcer disease. VacA, a toxin secreted by H. pylori, is comprised of two domains, designated p33 and p55. Analysis of the crystal structure of the p55 domain indicated that its structure is predominantly a right-handed parallel β-helix, which is a characteristic of autotransporter passenger domains. Substitution mutations of specific amino acids within the p33 domain abrogate VacA activity, but thus far, it has been difficult to identify small inactivating mutations within the p55 domain. Therefore, we hypothesized that large portions of the p55 domain might be non-essential for vacuolating toxin activity. To test this hypothesis, we introduced eight deletion mutations (each corresponding to a single coil within a β-helical segment spanning VacA amino acids 433-628 into the H. pylori chromosomal vacA gene. Results All eight of the mutant VacA proteins were expressed by the corresponding H. pylori mutant strains and underwent proteolytic processing to yield ~85 kDa passenger domains. Three mutant proteins (VacA Δ484-504, Δ511-536, and Δ517-544 were secreted and induced vacuolation of mammalian cells, which indicated that these β-helical coils were dispensable for vacuolating toxin activity. One mutant protein (VacA Δ433-461 exhibited reduced vacuolating toxin activity compared to wild-type VacA. Other mutant proteins, including those containing deletions near the carboxy-terminal end of the β-helical region (amino acids Val559-Asn628, exhibited marked defects in secretion and increased susceptibility to proteolytic cleavage by trypsin, which suggested that these proteins were misfolded. Conclusions These results indicate that within the β-helical segment of the VacA p55 domain, there are regions of plasticity that tolerate alterations without detrimental effects on protein

  5. Complementary DNA display selection of high-affinity peptides binding the vacuolating toxin (VacA) of Helicobacter pylori.

    Science.gov (United States)

    Hayakawa, Yumiko; Matsuno, Mitsuhiro; Tanaka, Makoto; Wada, Akihiro; Kitamura, Koichiro; Takei, Osamu; Sasaki, Ryuzo; Mizukami, Tamio; Hasegawa, Makoto

    2015-09-01

    Artificial peptides designed for molecular recognition of a bacterial toxin have been developed. Vacuolating cytotoxin A protein (VacA) is a major virulence factor of Helicobacter pylori, a gram-negative microaerophilic bacterium inhabiting the upper gastrointestinal tract, particularly the stomach. This study attempted to identify specific peptide sequences with high affinity for VacA using systematic directed evolution in vitro, a cDNA display method. A surface plasmon resonance-based biosensor and fluorescence correlation spectroscopy to examine binding of peptides with VacA identified a peptide (GRVNQRL) with high affinity. Cyclization of the peptide by attaching cysteine residues to both termini improved its binding affinity to VacA, with a dissociation constant (Kd ) of 58 nm. This study describes a new strategy for the development of artificial functional peptides, which are promising materials in biochemical analyses and medical applications.

  6. The Expression of VacA in BCF of Helicobacter Pylori and Its Relationship to Vacuolated Effect

    Institute of Scientific and Technical Information of China (English)

    施理; 侯晓华; 易粹琼; 张锦坤

    2002-01-01

    Summary: The vacuolated effect of Helicobacter (H. Pylori) and its relationship to vacuolated cyto toxin antigen (VacA) were investigated by the method of cytotoxic test and SDS-pobyacrylamide gel electrophoresis (SDS-PAGE). Of the 62 clinical isolates, the broth culture filter (BCF) of 43 strains causecl the Vero cell intracytoplasmically vacuolated. H. Pylori strains were divided into H. Pylori (Toxin+) group with vacuolated effect and H. Pylori (Toxin-) group without vacuolated effect. The analysis of the BCF of H. Pylori (Toxin+) and that of H. Pylori (Toxin-) was studied by SDS-PAGE and Scan reader. A kind of protein with 87 ku molecular weight was recognized in the BCF of 30.23 % (13/43) H. Pylori (Toxin+) strains but in none of that of H. Pylori (Toxin-) strains, the difference was statistically significant (P<0. 05). There was a significant and concordant relation ship between OD of the protein band with 87 ku molecular weight and titer of vacuolated activity of H. Pylori(Toxin+) (r=0. 67 and P<0. 05 by linear regression analysis). H. Pylori strains were di-vided into H. Pylori (Toxin+) group with vacuolated effect and H. Pylori (Toxin-) group without vacuolated effect. The vacuolated effect of H. Pylori (Toxin+) was caused by the protein with 87 ku molecular weight (VacA).

  7. Expression of 87 kD protein in the broth culture filtrate of Helicobacter pylori and its association with the vacuolating effect

    Institute of Scientific and Technical Information of China (English)

    SHI Li; YIE Gui-an; NAN Qing-zhen; SUN Yong; ZHANG Ya-li; ZHANG Zhen-shu; ZHOU Dian-yuan

    2001-01-01

    To study the vacuolating effect of Helicobacter pylori(H.pylori). Method: The vacuolating effect and its relationship with vacuolating cytotoxin antigen (an 87 kD protein) were investigated by the method of cytotoxic test, SDS-PAGE and scanning. Result: Of the 62 clinical isolates, 43 strains were H.pylori (Toxin+) with vacuolating effect, while the others were H.pylori (Toxin-) without vacuolating effect. Altogether 78.26%(36/46) patients with peptic ulcer were infected with H.pylori (Toxin+) strains, and only 42.86%(6/14) who had gastritis were infected with H.pylori (Toxin+) strains, with significant difference between them(χ2=4.83,P<0.05). A protein with relativemolecular mass of 87 kD was identified in the broth culture filter(BCF) of 30.23% H. Pylori (Toxin+) strains (13/43) but in none of that of H.pylori (Toxin-) strains, and the difference was statistically significant(P<0.05). There was a significant and concordant relationship between the OD value of the protein band and the titer of vacuolating activity of H.pylori (Toxin+) (r=0.67 and P<0.05 by linear regression analysis). Conclusion: H.pylori (Toxin+) were more often associated with peptic ulcerous diseases than with gastritis diseases. The vacuolating effect of H.pylori (Toxin+) may be caused by the 87 kD protein.

  8. Methods to monitor autophagy in H. pylori vacuolating cytotoxin A (VacA)-treated cells.

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    Raju, Deepa; Jones, Nicola L

    2010-01-01

    Helicobacter pylori is a gram negative pathogen that infects at least half of the world's population and is associated not only with gastric cancer but also with other diseases such as gastritis and peptic ulcers. Indeed, H. pylori is considered the single most important risk factor for the development of gastric cancer. The vacuolating cytotoxin VacA, secreted by H. pylori, promotes intracellular survival of the bacterium and modulates host immune responses. In a recent study, we reported that VacA induces autophagy. Multilamellar autophagosomes are detected in gastric epithelial cells that are distinct from the large vacuoles formed by VacA. Furthermore, inhibition of autophagy stabilizes VacA and reduces vacuolation in the cells indicating that the toxin is being degraded by autophagy, thus limiting toxin-induced host cell damage. Many of the methods that were used for this study are commonly employed techniques that were adapted for H. pylori infection and VacA intoxication. In this paper, we describe the various methods and specific protocols used for the assessment and monitoring of autophagy during H. pylori infection.

  9. Characterization of the Vacuolating Cytotoxin in Helicobacter pylori Strains Isolated from Iran

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    Akbar Oghalaie

    2010-01-01

    Full Text Available Objective: Helicobacter pylori (H. pylori cytotoxin and its heterogeneity amongst strains hasbeen closely linked to the varying infection-associated clinical outcomes. In order to determinethe decisive role of the vacuolating cytotoxin (vacA gene mosaicism in its corresponding geneexpression and phenotype, we aimed to characterize vacA alleles of different H. pylori strainsin addition to the resulting protein and its vacuolating activity in epithelial cell culture.Materials and Methods: vacA gene polymorphism was determined for 80 H. pylori strainsisolated from dyspeptic patients, using multiplex gene-specific polymerase chain reaction(PCR. VacA protein was detected by immuno-blotting assay using a polyclonal anti-VacAantibody. In vitro cytotoxicity assay was conducted on HeLa cells in order to evaluate thevacuolating cytotoxin activity.Results: Genotyping revealed the following strain distribution: 26 (32.5% s1m1, 35(43.8% s1m2, and 19 (23.8% s2m2 subtypes. Infection with s1m1 type strain was significantlyassociated with gastric cancer as compared to non-ulcer dyspepsia (p=0.005and peptic ulcer disease (p=0.008. A 95-kDa immuno-reactive band that represented thevacuolating toxin was demonstrated in SDS-PAGE analysis of concentrated culture filtrate(CCF of H. pylori strains. H. pylori CCFs induced HeLa cell vacuolation which correlatedwith the strain genotype; s1m1 strains demonstrated higher levels of vacuolation as comparedto s1m2 strains, whereas s2m2 strains showed no detectable cytotoxic activity.Conclusion: The current study confirmed the relatively high cytotoxic activity of s1m1type H. pylori strains which infect the majority of patients suffering from gastric cancer andmay be partly responsible for the pathogenesis of this mortal disease.

  10. Effect of Helicobacter pylori's vacuolating cytotoxin on the autophagy pathway in gastric epithelial cells.

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    Terebiznik, Mauricio R; Raju, Deepa; Vázquez, Cristina L; Torbricki, Karl; Kulkarni, Reshma; Blanke, Steven R; Yoshimori, Tamotsu; Colombo, María I; Jones, Nicola L

    2009-04-01

    Host cell responses to Helicobacter pylori infection are complex and incompletely understood. Here, we report that autophagy is induced within human-derived gastric epithelial cells (AGS) in response to H. pylori infection. These autophagosomes were distinct and different from the large vacuoles induced during H. pylori infection. Autophagosomes were detected by transmission electron microscopy, conversion of LC3-I to LC3-II, GFP-LC3 recruitment to autophagosomes, and depended on Atg5 and Atg12. The induction of autophagy depended on the vacuolating cytotoxin (VacA) and, moreover, VacA was sufficient to induce autophagosome formation. The channel-forming activity of VacA was necessary for inducing autophagy. Intracellular VacA partially co-localized with GFP-LC3, indicating that the toxin associates with autophagosomes. The inhibition of autophagy increased the stability of intracellular VacA, which in turn resulted in enhanced toxin-mediated cellular vacuolation. These findings suggest that the induction of autophagy by VacA may represent a host mechanism to limit toxin-induced cellular damage.

  11. The vacuolating cytotoxin of Helicobacter pylori%幽门螺杆菌空泡毒素研究进展

    Institute of Scientific and Technical Information of China (English)

    刘纯杰; 陶好霞; 张兆山

    2001-01-01

    幽门螺杆菌空泡毒素是该菌产生的与已知其它细菌毒素无明显同源性的唯一蛋白毒素。该毒素是幽门螺杆菌重要的毒力致病因子,它的产生与感染者胃肠上皮损伤和溃疡形成密切相关。本文就幽门螺杆菌空泡毒素的结构与功能研究进展以及在未来免疫预防与免疫治疗中的作用进行了简述。%The vacuolating cytotoxin is a unique proteinous cytotoxin producted by H. pylori that showed no striking primary sequence homology with other known baterial toxins. The cytotoxin is an important fator in the pathogenesis of H. pylori, which induces vacuolation of epithelial cells and plays an important role in gastric epithelial necrosis and peptic ulceration. In the paper, the progress on structure and function of the vacuolating cytotoxin of H. pylori and the roles of the H. pylori vacuolating cytotoxin in the future immunoprophylaxis and immunotherapy were reviewed.

  12. Pleiotropic actions of Helicobacter pylori vacuolating cytotoxin, VacA.

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    Isomoto, Hajime; Moss, Joel; Hirayama, Toshiya

    2010-01-01

    Helicobacter pylori produces a vacuolating cytotoxin, VacA, and most virulent H. pylori strains secrete VacA. VacA binds to two types of receptor-like protein tyrosine phosphatase (RPTP), RPTPalpha and RPTPbeta, on the surface of host cells. VacA bound to RPTPbeta, relocates and concentrates in lipid rafts in the plasma membrane. VacA causes vacuolization, membrane anion-selective channel and pore formation, and disruption of endosomal and lysosomal activity in host cells. Secreted VacA is processed into p33 and p55 fragments. The p55 domain not only plays a role in binding to target cells but also in the formation of oligomeric structures and anionic membrane channels. Oral administration of VacA to wild-type mice, but not to RPTPbeta knockout mice, resulted in gastric ulcers, in agreement with the clinical effect of VacA. VacA with s1/m1 allele has more potent cytotoxic activity in relation to peptic ulcer disease and appears to be associated with human gastric cancer. VacA activates pro-apoptotic Bcl-2 family proteins, and induces apoptosis via a mitochondria-dependent pathway. VacA can disrupt other signal transduction pathways; VacA activates p38 MAPK, enhancing production of IL-8 and PGE(2), and PI3K/Akt, suppressing GSK-3beta activity. VacA has immunomodulatory actions on T cells and other immune cells, possibly contributing to the chronic infection seen with this organism. H. pylori virulence factors including VacA and CagA, which is encoded by cytotoxin-associated gene A, along with host genetic and environmental factors, constitute a complex network to regulate chronic gastric injury and inflammation, which is involved in a multistep process leading to gastric carcinogenesis.

  13. An Overview of Helicobacter pylori VacA Toxin Biology

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    Foegeding, Nora J.; Caston, Rhonda R.; McClain, Mark S.; Ohi, Melanie D.; Cover, Timothy L.

    2016-01-01

    The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease. PMID:27271669

  14. An Overview of Helicobacter pylori VacA Toxin Biology

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    Nora J. Foegeding

    2016-06-01

    Full Text Available The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease.

  15. THE EXPRESSION OF VACA IN THE BCF OF HELICOBACTER PYLORI AND ITS RELATIONSHIP TO THE VACUOLATED EFFECT%VacA在幽门螺杆菌BCF中的表达及其与空泡毒作用的关系

    Institute of Scientific and Technical Information of China (English)

    施理; 侯晓华; 易粹琼

    2002-01-01

    目的:研究幽门螺杆菌(Helicobacter pylori,H.pylori)临床分离株的空泡毒作用及其与空泡毒素抗原(Vacuolated cytotoxin antigen,VacA)的关系.方法:用细胞毒试验、SDS-PAGE结合薄层扫描研究H.pylori临床分离株空泡毒作用及其与VacA的关系.结果:62株H.pylori临床分离株,43株为空泡毒作用阳性 H.pylori(Toxin+) ,其余为空泡毒作用阴性的H.pylori(Toxin-).30.23%(13/43)H.pylori(Toxin+)临床分离株的肉汤培养滤液(broth culture filter,BCF)含有分子量为87 kDa的VacA,而所有H.pylori(Toxin-)的BCF不含有这种蛋白,二者之间差异有显著性(P<0.05);VacA含量与H.pylori(Toxin+)BCF的空泡毒作用滴度明显相关(r=0.67,P<0.05).结论:H.pylori(Toxin+)空泡毒作用是由VacA引起的.

  16. Essential domain of receptor tyrosine phosphatase beta (RPTPbeta) for interaction with Helicobacter pylori vacuolating cytotoxin

    DEFF Research Database (Denmark)

    Yahiro, Kinnosuke; Wada, Akihiro; Yamasaki, Eiki

    2004-01-01

    Helicobacter pylori produces a potent exotoxin, VacA, which causes progressive vacuolation as well as gastric injury. Although VacA was able to interact with two receptor-like protein tyrosine phosphatases, RPTPbeta and RPTPalpha, RPTPbeta was found to be responsible for gastric damage caused...

  17. Cellular vacuoles induced by Mycoplasma pneumoniae CARDS toxin originate from Rab9-associated compartments.

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    Coreen Johnson

    Full Text Available Recently, we identified an ADP-ribosylating and vacuolating cytotoxin in Mycoplasma pneumoniae designated Community Acquired Respiratory Distress Syndrome (CARDS toxin. In this study we show that vacuoles induced by recombinant CARDS (rCARDS toxin are acidic and derive from the endocytic pathway as determined by the uptake of neutral red and the fluid-phase marker, Lucifer yellow, respectively. Also, we demonstrate that the formation of rCARDS toxin-associated cytoplasmic vacuoles is inhibited by the vacuolar ATPase inhibitor, bafilomycin A1, and the ionophore, monensin. To examine the ontogeny of these vacuoles, we analyzed the distribution of endosomal and lysosomal membrane markers during vacuole formation and observed the enrichment of the late endosomal GTPase, Rab9, around rCARDS toxin-induced vacuoles. Immunogold-labeled Rab9 and overexpression of green fluorescent-tagged Rab9 further confirmed vacuolar association. The late endosomal- and lysosomal-associated membrane proteins, LAMP1 and LAMP2, also localized to the vacuolar membranes, while the late endosomal protein, Rab7, and early endosomal markers, Rab5 and EEA1, were excluded. HeLa cells expressing dominant-negative (DN Rab9 exhibited markedly reduced vacuole formation in the presence of rCARDS toxin, in contrast to cells expressing DN-Rab7, highlighting the importance of Rab9 function in rCARDS toxin-induced vacuolation. Our findings reveal the unique Rab9-association with rCARDS toxin-induced vacuoles and its possible relationship to the characteristic histopathology that accompanies M. pneumoniae infection.

  18. [A single strand comformation polymorphism of vacuolating cytotoxin gene in H. pylori].

    Science.gov (United States)

    Peng, H; Pan, G; Chao, S

    1999-03-01

    To use PCR/SSCP analysis of the vacuolating cytotoxin gene (vacA) of H. pylori for differentiation of various strains of H. pylori. PCR was performed using the primers amplifing vacA gene of the bacteria embeded in the gastric mucosa of 159 patients with various gastric duodenal diseases. The products of PCR were further processed for SSCP analysis and southern blot hybridization. In the meantime, vacA genes of three different SSCP-patterns from three patients with duodenal ulcers were sequenced. The rate of detection of H. pylori with the method was 100%. vacA1 and vacA2, the two subtypes of vacA, were 76.5% (114/149) and 23.5%(35/149), respectively. Eight different SSCP-patterns were distributed in various gastroduodenal diseases, and that 80% of duodenal ulcers was predominated with B pattern. Sequencing of DNA indicated a diversity of vacA gene structure. PCR/SSCP can be used in the differentiation of different strains of H. pylori in epidemology, and in the follow up study after H. pylori eradication, especially in the differentiation between H. pylori recrudescence and reinfection.

  19. Natural Diversity in the N Terminus of the Mature Vacuolating Cytotoxin of Helicobacter pylori Determines Cytotoxin Activity

    OpenAIRE

    Letley, D. P.; Atherton, J C

    2000-01-01

    Naturally occurring noncytotoxic vacA type s2 strains of Helicobacter pylori have a 12-residue extension to the vacuolating cytotoxin (VacA) compared with cytotoxic type s1 strains. We show that adding the region encoding this extension to type s1 vacA completely abolishes vacuolating cytotoxin activity but has no effect on VacA production.

  20. Effect of NaCl and Helicobacter pylori vacuolating cytotoxin on cytokine expression and viability

    Institute of Scientific and Technical Information of China (English)

    Juan Sun; Kazuo Aoki; Jin-Xu Zheng; Bing-Zhong Su; Xiao-Hui Ouyang; Junichi Misumi

    2006-01-01

    AIM: To determine whether Helicobacter pylori (H pylori) vacuolating cytotoxin (VacA) regulates release of proinflammatory cytokines (IL-1β, IL-8, TNF-α, and IL-6)or alters gastric epithelial cell viability and to determine whether NaCl affects these VacA-induced changes.METHODS: Vacuolating activity was determined by measuring the uptake of neutral red into vacuoles of VacA-treated human gastric epithelial (AGS) cells. AGS cell viability was assessed by direct cell counting. Specific enzyme-linked immunosorbent assays (ELISA) and reverse transcriptase-polymerase chain reaction(RT-PCR)were performed to examine the effects of Hpylori VacA and NaCl on cell pro-inflammatory cytokine production in AGS cells. Immunohistochemical staining of gastric tissue from Mongolian gerbils was used to confirm VacA-induced pro-inflammatory cytokine production and the effects of NaCl on this VacA-induced response.RESULTS: Addition of VacA alone reduced AGS cell viability (P< 0.05), and this reduction was enhanced by high doses of NaCl (P< 0.05). VacA alone induced expression of TNF-α, IL-8 and IL-1β, while NaCl alone induced expression of TNF-α and IL-1β. Changes in mRNA levels in the presence of both VacA and NaCl were more complicated. For the case of TNF-a, expression was dosedependent on NaCl. IL-6 mRNA was not detected. However, low levels of IL-6 were detected by ELISA. Positive immunohistochemical staining of IL- 1, IL-6, and TNF-αwas found in gastric tissue of H pylori-infected gerbils fed with either a normal diet or a high salt diet. However,the staining of these three cytokines was stronger in H pylori-infected animals fed with a 5g/kg NaCl diet.CONCLUSION: VacA decreases the viability of AGS cells, and this effect can be enhanced by NaCl. NaCl also affects the production of pro-inflammatory cytokines induced by Vac A, suggesting that NaCl plays an important role in Hpylori-induced gastric epithelial cell cytotoxicity.

  1. High Cell Sensitivity to Helicobacter pylori VacA Toxin Depends on a GPI-anchored Protein and is not Blocked by Inhibition of the Clathrin-mediated Pathway of Endocytosis

    OpenAIRE

    2000-01-01

    Helicobacter pylori vacuolating toxin (VacA) causes vacuolation in a variety of cultured cell lines, sensitivity to VacA differing greatly, however, among the different cell types. We found that the high sensitivity of HEp-2 cells to VacA was impaired by treating the cells with phosphatidylinositol-specific phospholipase C (PI-PLC) which removes glycosylphosphatidylinositol (GPI)-anchored proteins from the cell surface. Incubation of cells with a cholesterol-seques...

  2. the versatility of the Helicobacter pylori vacuolating cytotoxin vacA in signal transduction and molecular crosstalk.

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    Backert, Steffen; Tegtmeyer, Nicole

    2010-01-01

    By modulating important properties of eukaryotic cells, many bacterial protein toxins highjack host signalling pathways to create a suitable niche for the pathogen to colonize and persist. Helicobacter pylori VacA is paradigm of pore-forming toxins which contributes to the pathogenesis of peptic ulceration. Several cellular receptors have been described for VacA, which exert different effects on epithelial and immune cells. The crystal structure of VacA p55 subunit might be important for elucidating details of receptor interaction and pore formation. Here we discuss the multiple signalling activities of this important toxin and the molecular crosstalk between VacA and other virulence factors.

  3. Characterization of Helicobacter pylori VacA-containing vacuoles (VCVs), VacA intracellular trafficking and interference with calcium signalling in T lymphocytes.

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    Kern, Beate; Jain, Utkarsh; Utsch, Ciara; Otto, Andreas; Busch, Benjamin; Jiménez-Soto, Luisa; Becher, Dörte; Haas, Rainer

    2015-12-01

    The human pathogen Helicobacter pylori colonizes half of the global population. Residing at the stomach epithelium, it contributes to the development of diseases such as gastritis, duodenal and gastric ulcers, and gastric cancer. A major factor is the secreted vacuolating toxin VacA, which forms anion-selective channels in the endosome membrane that cause the compartment to swell, but the composition and purpose of the resulting VacA-containing vacuoles (VCVs) are still unknown. VacA exerts influence on the host immune response in various ways, including inhibition of T-cell activation and proliferation and suppression of the host immune response. In this study, for the first time the composition of VCVs from T cells was comprehensively analysed to investigate VCV function. VCVs were successfully isolated via immunomagnetic separation, and the purified vacuoles were analysed by mass spectrometry. We detected a set of 122 VCV-specific proteins implicated among others in immune response, cell death and cellular signalling processes, all of which VacA is known to influence. One of the individual proteins studied further was stromal interaction molecule (STIM1), a calcium sensor residing in the endoplasmic reticulum (ER) that is important in store-operated calcium entry. Live cell imaging microscopy data demonstrated colocalization of VacA with STIM1 in the ER and indicated that VacA may interfere with the movement of STIM1 towards the plasma membrane-localized calcium release activated calcium channel protein ORAI1 in response to Ca(2+) store depletion. Furthermore, VacA inhibited the increase of cytosolic-free Ca(2+) in the Jurkat E6-1 T-cell line and human CD4(+) T cells. The presence of VacA in the ER and its trafficking to the Golgi apparatus was confirmed in HeLa cells, identifying these two cellular compartments as novel VacA target structures.

  4. Structure of CARDS toxin, a unique ADP-ribosylating and vacuolating cytotoxin from Mycoplasma pneumoniae.

    Science.gov (United States)

    Becker, Argentina; Kannan, T R; Taylor, Alexander B; Pakhomova, Olga N; Zhang, Yanfeng; Somarajan, Sudha R; Galaleldeen, Ahmad; Holloway, Stephen P; Baseman, Joel B; Hart, P John

    2015-04-21

    Mycoplasma pneumoniae (Mp) infections cause tracheobronchitis and "walking" pneumonia, and are linked to asthma and other reactive airway diseases. As part of the infectious process, the bacterium expresses a 591-aa virulence factor with both mono-ADP ribosyltransferase (mART) and vacuolating activities known as Community-Acquired Respiratory Distress Syndrome Toxin (CARDS TX). CARDS TX binds to human surfactant protein A and annexin A2 on airway epithelial cells and is internalized, leading to a range of pathogenetic events. Here we present the structure of CARDS TX, a triangular molecule in which N-terminal mART and C-terminal tandem β-trefoil domains associate to form an overall architecture distinct from other well-recognized ADP-ribosylating bacterial toxins. We demonstrate that CARDS TX binds phosphatidylcholine and sphingomyelin specifically over other membrane lipids, and that cell surface binding and internalization activities are housed within the C-terminal β-trefoil domain. The results enhance our understanding of Mp pathogenicity and suggest a novel avenue for the development of therapies to treat Mp-associated asthma and other acute and chronic airway diseases.

  5. Sat, the secreted autotransporter toxin of uropathogenic Escherichia coli, is a vacuolating cytotoxin for bladder and kidney epithelial cells.

    Science.gov (United States)

    Guyer, Debra M; Radulovic, Suzana; Jones, Faye-Ellen; Mobley, Harry L T

    2002-08-01

    The secreted autotransporter toxin (Sat) of uropathogenic Escherichia coli exhibits cytopathic activity upon incubation with HEp-2 cells. We further investigated the effects of Sat on cell lines more relevant to the urinary tract, namely, those derived from bladder and kidney epithelium. Sat elicited elongation of cells and apparent loosening of cellular junctions upon incubation with Vero kidney cells. Additionally, incubation with Sat triggered significant vacuolation within the cytoplasm of both human bladder (CRL-1749) and kidney (CRL-1573) cell lines. This activity has been associated with only a few other known toxins. Following transurethral infection of CBA mice with a sat mutant, no reduction of CFU in urine, bladder, or kidney tissue was seen compared to that in mice infected with wild-type E. coli CFT073. However, significant histological changes were observed within the kidneys of mice infected with wild-type E. coli CFT073, including dissolution of the glomerular membrane and vacuolation of proximal tubule cells. Such damage was not observed in kidney sections of mice infected with a Sat-deficient mutant. These results indicate that Sat, a vacuolating cytotoxin expressed by uropathogenic E. coli CFT073, elicits defined damage to kidney epithelium during upper urinary tract infection and thus contributes to pathogenesis of urinary tract infection.

  6. DNA Sequence Analysis of South African Helicobacter pylori Vacuolating Cytotoxin Gene (vacA)

    Science.gov (United States)

    Tanih, Nicoline F.; Ndip, Lucy M.; Ndip, Roland N.

    2011-01-01

    Sequence diversity and population structures can vary widely among pathogenic bacteria species. In some species, all isolates are highly similar, whereas in others most of the isolates are distinguished easily. H. pylori is known for its wide genetic diversity amongst the various strains most especially in the genes involved in virulence. The aim of this study was to evaluate by PCR and sequence analysis, the genetic profile of H. pylori vacA gene (s1, s2, m1 and m2). We sequenced small DNA segments from 13 vacAs1, 10 vacAm2, 6 vacAm1 and 6 vacAs2 strains which were amplified with amplicon size of 259/286 bp, 290 bp and 352 bp for vacAs1/s2, m1 and m2 respectively. Based on similarities among our strains accession numbers were provided for seven vacAs1 (HQ709109–HQ709115), six vacAs2 (JN848463–JN848468), six vacAm1 (JN848469–JN848474) and six vacAm2 (HQ650801–HQ650806) strains. Amongst the strains studied, 98.07%, 98.58%, 97.38% and 95.41% of vacAs1, vacAs2, vacAm1 and vacAm2 of the strains were conserved respectively. Findings of this study underscores the importance of understanding the virulence composition and diversity of H. pylori in South Africa for enhanced clinico-epidemiological monitoring and pathophysiology of disease. PMID:22174610

  7. Helicobacter pylori VacA toxin/subunit p34: targeting of an anion channel to the inner mitochondrial membrane.

    Directory of Open Access Journals (Sweden)

    Grazyna Domańska

    2010-04-01

    Full Text Available The vacuolating toxin VacA, released by Helicobacter pylori, is an important virulence factor in the pathogenesis of gastritis and gastroduodenal ulcers. VacA contains two subunits: The p58 subunit mediates entry into target cells, and the p34 subunit mediates targeting to mitochondria and is essential for toxicity. In this study we found that targeting to mitochondria is dependent on a unique signal sequence of 32 uncharged amino acid residues at the p34 N-terminus. Mitochondrial import of p34 is mediated by the import receptor Tom20 and the import channel of the outer membrane TOM complex, leading to insertion of p34 into the mitochondrial inner membrane. p34 assembles in homo-hexamers of extraordinary high stability. CD spectra of the purified protein indicate a content of >40% beta-strands, similar to pore-forming beta-barrel proteins. p34 forms an anion channel with a conductivity of about 12 pS in 1.5 M KCl buffer. Oligomerization and channel formation are independent both of the 32 uncharged N-terminal residues and of the p58 subunit of the toxin. The conductivity is efficiently blocked by 5-nitro-2-(3-phenylpropylaminobenzoic acid (NPPB, a reagent known to inhibit VacA-mediated apoptosis. We conclude that p34 essentially acts as a small pore-forming toxin, targeted to the mitochondrial inner membrane by a special hydrophobic N-terminal signal.

  8. 幽门螺杆菌空泡细胞毒素(Vacuolating cytotoxin,VacA)研究进展%Study on Vacuolating Cytotoxin of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    赵雩卿; 钱家鸣

    2004-01-01

    1988年Leunk等发现幽门螺杆菌(Helicobacter pylori,H.pylori)肉汤培养基的上清液含有一种使多种体外培养的真核细胞系发生空泡样变性的毒素,1992年这种毒素得以纯化并被命名为空泡细胞毒素(Vacuo1ating cytotoxin,VacA)。1994年完成了编码VacA的基因vacA的克隆和序列分析,由此VacA作为H.pylori致病的主要毒力因子引起了研究者的广泛兴趣和关注,本文将综述近十年有关VacA的研究进展。

  9. High Cell Sensitivity to Helicobacter pylori VacA Toxin Depends on a GPI-anchored Protein and is not Blocked by Inhibition of the Clathrin-mediated Pathway of Endocytosis

    Science.gov (United States)

    Ricci, Vittorio; Galmiche, Antoine; Doye, Anne; Necchi, Vittorio; Solcia, Enrico; Boquet, Patrice

    2000-01-01

    Helicobacter pylori vacuolating toxin (VacA) causes vacuolation in a variety of cultured cell lines, sensitivity to VacA differing greatly, however, among the different cell types. We found that the high sensitivity of HEp-2 cells to VacA was impaired by treating the cells with phosphatidylinositol-specific phospholipase C (PI-PLC) which removes glycosylphosphatidylinositol (GPI)-anchored proteins from the cell surface. Incubation of cells with a cholesterol-sequestering agent, that impairs both structure and function of sphingolipid-cholesterol-rich membrane microdomains (“lipid rafts”), also impaired VacA-induced cell vacuolation. Overexpression into HEp-2 cells of proteins inhibiting clathrin-dependent endocytosis (i.e., a dominant-negative mutant of Eps15, the five tandem Src-homology-3 domains of intersectin, and the K44A dominant-negative mutant of dynamin II) did not affect vacuolation induced by VacA. Nevertheless, F-actin depolymerization, known to block the different types of endocytic mechanisms, strongly impaired VacA vacuolating activity. Taken together, our data suggest that the high cell sensitivity to VacA depends on the presence of one or several GPI-anchored protein(s), intact membrane lipid rafts, and an uptake mechanism via a clathrin-independent endocytic pathway. PMID:11071915

  10. Helicobacter pylori counteracts the apoptotic action of its VacA toxin by injecting the CagA protein into gastric epithelial cells.

    Directory of Open Access Journals (Sweden)

    Amanda Oldani

    2009-10-01

    Full Text Available Infection with Helicobacter pylori is responsible for gastritis and gastroduodenal ulcers but is also a high risk factor for the development of gastric adenocarcinoma and lymphoma. The most pathogenic H. pylori strains (i.e., the so-called type I strains associate the CagA virulence protein with an active VacA cytotoxin but the rationale for this association is unknown. CagA, directly injected by the bacterium into colonized epithelium via a type IV secretion system, leads to cellular morphological, anti-apoptotic and proinflammatory effects responsible in the long-term (years or decades for ulcer and cancer. VacA, via pinocytosis and intracellular trafficking, induces epithelial cell apoptosis and vacuolation. Using human gastric epithelial cells in culture transfected with cDNA encoding for either the wild-type 38 kDa C-terminal signaling domain of CagA or its non-tyrosine-phosphorylatable mutant form, we found that, depending on tyrosine-phosphorylation by host kinases, CagA inhibited VacA-induced apoptosis by two complementary mechanisms. Tyrosine-phosphorylated CagA prevented pinocytosed VacA to reach its target intracellular compartments. Unphosphorylated CagA triggered an anti-apoptotic activity blocking VacA-induced apoptosis at the mitochondrial level without affecting the intracellular trafficking of the toxin. Assaying the level of apoptosis of gastric epithelial cells infected with wild-type CagA(+/VacA(+H. pylori or isogenic mutants lacking of either CagA or VacA, we confirmed the results obtained in cells transfected with the CagA C-ter constructions showing that CagA antagonizes VacA-induced apoptosis. VacA toxin plays a role during H. pylori stomach colonization. However, once bacteria have colonized the gastric niche, the apoptotic action of VacA might be detrimental for the survival of H. pylori adherent to the mucosa. CagA association with VacA is thus a novel, highly ingenious microbial strategy to locally protect its

  11. Polymorphism in the Helicobacter pylori CagA and VacA toxins and disease

    Science.gov (United States)

    Bridge, Dacie R.; Merrell, D. Scott

    2013-01-01

    Half of the world’s population is infected with Helicobacter pylori and approximately 20% of infected individuals develop overt clinical disease such as ulcers and stomach cancer. Paradoxically, despite its classification as a class I carcinogen, H. pylori has been shown to be protective against development of asthma, allergy, and esophageal disease. Given these conflicting roles for H. pylori, researchers are attempting to define the environmental, host, and pathogen interactions that ultimately result in severe disease in some individuals. From the bacterial perspective, the toxins, CagA and VacA, have each been shown to be polymorphic and to contribute to disease in an allele-dependent manner. Based on the notable advances that have recently been made in the CagA field, herein we review recent studies that have begun to shed light on the role of CagA polymorphism in H. pylori disease. Moreover, we discuss the potential interaction of CagA and VacA as a mediator of gastric disease. PMID:23380646

  12. Vacuolating cytotoxin genotypes are strong markers of gastric cancer and duodenal ulcer-associated Helicobacter pylori strains: a matched case-control study.

    Science.gov (United States)

    Memon, Ameer A; Hussein, Nawfal R; Miendje Deyi, Véronique Y; Burette, Alain; Atherton, John C

    2014-08-01

    The Helicobacter pylori virulence gene, cagA, and active forms of the vacuolating cytotoxin gene, vacA, are major determinants of pathogenesis. However, previous studies linking these factors to disease risk have often included patients using aspirin/nonsteroidal anti-inflammatory agents (NSAIDs) or acid-suppressing drugs, both of which may confound results. Also, particularly for gastric cancer (GC), controls have often been of quite different ages. Here, we performed a careful study in a "clean" Belgian population with gastric cancer cases age and sex matched to 4 controls and with a parallel duodenal ulcer (DU) group. As in other populations, there was a close association between the presence of cagA and the vacA s1 genotype. For GC, associations were found for vacA s1-positive (P = 0.01, odds ratio [OR], 9.37; 95% confidence interval [CI], 1.16 to 201.89), i1-positive (P = 0.003; OR, 12.08; 95% CI, 1.50 to 259.64), and cagA-positive status (P ulcer-associated strains are the vacA s1 and i1 genotypes. This fits with experimental data showing that the s and i regions are the key determinants of vacuolating cytotoxin activity.

  13. Prevalence of Helicobacter pylori vacuolating cytotoxin and its allelic mosaicism as a predictive marker for Iranian dyspeptic patients

    DEFF Research Database (Denmark)

    Mohammadi, M; Oghalaie, A; Mohajerani, N

    2003-01-01

    Helicobacter pylori infects the majority of the population in the developing countries. However, the rate of gastrointestinal complications such as peptic ulcers and gastric malignancies has no parallel with the infection. In order to determine whether cytotoxin (vacA) and its allelic polymorphis...

  14. Piperine treatment suppresses Helicobacter pylori toxin entry in to gastric epithelium and minimizes β-catenin mediated oncogenesis and IL-8 secretion in vitro.

    Science.gov (United States)

    Tharmalingam, Nagendran; Park, Min; Lee, Min Ho; Woo, Hyun Jun; Kim, Hyun Woo; Yang, Ji Yeong; Rhee, Ki-Jong; Kim, Jong-Bae

    2016-01-01

    Helicobacter pylori related gastric cancer initiation has been studied widely. The objective of our present study was to evaluate the effect of a single compound piperine on H. pylori infection and its anti-inflammatory and anti-cancer effects in vitro. Cytotoxicity was tested by Ez-cytox cell viability assay kit. Effects of piperine on H. pylori toxin gene expression and IL-8 expression in mammalian cells during infection were assessed by RT-PCR. Effects of piperine on toxin entry into host cells, E-cadherin cleavage by H. pylori, and the changes in H. pylori mediated β-catenin expression and IL-8 secretion were determined by immunoblotting. Piperine treatment restrained the entry of CagA and VacA into AGS cells. Piperine administration in H. pylori infection reduced E-cadherin cleavage in stomach epithelium. In addition, H. pylori induced β-catenin up-regulation was reduced. Piperine administration impaired IL-8 secretion in H. pylori-infected gastric epithelial cells. As we reported previously piperine restrained H. pylori motility. The possible reason behind the H. pylori inhibition mechanism of piperine could be the dwindled motility, which weakened H. pylori adhesion to gastric epithelial cells. The reduced adhesion decreased the toxin entry thereby secreting less amount of IL-8. In addition, piperine treatment suppressed H. pylori protease led to reduction of E-cadherin cleavage and β-catenin expression resulting in diminished β-catenin translocation into the nucleus thus decreasing the risk of oncogenesis. To our knowledge, this is the preliminary report of piperine mediated H. pylori infection control on gastric epithelial cells in-vitro.

  15. Recombinant Bacillus subtilis spores expressing cholera toxin B subunit and Helicobacter pylori urease B confer protection against H. pylori in mice.

    Science.gov (United States)

    Zhou, Zhenwen; Dong, Hui; Huang, Yanmei; Yao, Shuwen; Liang, Bingshao; Xie, Yongqiang; Long, Yan; Mai, Jialiang; Gong, Sitang

    2017-01-01

    Helicobacter pylori infection is associated with chronic gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. The limitations of current therapies for H. pylori infection include poor compliance and antibiotic resistance. Therefore, an effective anti-H. pylori vaccine would be an alternative or complement to antibiotic treatment. Urease B (UreB) is considered an ideal vaccine antigen against H. pylori infection. In this study, cholera toxin B subunit (CTB), a mucosal adjuvant, was used to enhance the immunogenicity of a novel Bacillus subtilis spore vaccine expressing CTB-UreB, along with the B. subtilis spore coat protein CotC as a fusion protein. Oral administration of B. subtilis spores expressing CotC-UreB or CotC-CTB-UreB led to increased levels of UreB-specific IgG in serum and UreB-specific IgA in faeces, as well as elevated levels of IL-10 and IFN-γ in splenocytes. In addition, oral administration of CotC-UreB or CotC-CTB-UreB spores induced significant reductions (80.0 and 90.5 %, respectively) in gastric H. pylori bacterial load (1.11±0.36×105 and 0.53±0.21×105 c.f.u., respectively) compared to that of the CotC control group (5.56±1.64×105 c.f.u., P<0.01). Moreover, CotC-CTB-UreB spores were significantly more effective at reducing the bacterial load than CotC-UreB spores (P<0.05). These results indicate that CotC-CTB-UreB-expressing B. subtilis spores are a potential vaccine candidate for the control of H. pylori infection.

  16. Piperine treatment suppresses Helicobacter pylori toxin entry in to gastric epithelium and minimizes β-catenin mediated oncogenesis and IL-8 secretion in vitro

    OpenAIRE

    2016-01-01

    Helicobacter pylori related gastric cancer initiation has been studied widely. The objective of our present study was to evaluate the effect of a single compound piperine on H. pylori infection and its anti-inflammatory and anti-cancer effects in vitro. Cytotoxicity was tested by Ez-cytox cell viability assay kit. Effects of piperine on H. pylori toxin gene expression and IL-8 expression in mammalian cells during infection were assessed by RT-PCR. Effects of piperine on toxin entry into host ...

  17. Cytopathic effects of toxogenic strains of Helicobacter pylori on different cell lines

    Directory of Open Access Journals (Sweden)

    K. Lakshmana Gowda

    2014-01-01

    Full Text Available Purpose: Many virulence factors are involved in the pathomechanism of infection caused by Helicobacter pylori. Toxins such as vacuolating cytotoxin, encoded by the vacA gene and the immunogenic protein cagA, encoded by the cagA gene (cytotoxin-associated gene are major factors conferring the property of virulence. The current study is aimed at isolation of H. pylori and separation of its toxin from antral biopsies of patients. Materials and Methods: The following cell lines were used to demonstrate the cytopathic effect (CPE of the separated toxin: African green monkey kidney (Vero, baby hamster kidney, human lung carcinoma (LLC-MK2, and human epithelial. Results: H. pylori was isolated from 27 out of 45 patients (60% selected for the study. CPE of H. pylori toxin was highly significant on Vero cells than other cell lines used as it reached a high dilution titer of toxin (1/16 in 13 isolated strains (48.15%. No significant difference in CPE of toxin in different dilutions was detected among other cell lines used in different groups. H. pylori toxin could be detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis as a distinct band with a molecular weight ranging between 66 and 97 kDa and closely related to 87 kDa. Conclusion: H. pylori vacuolating cytotoxin plays a vital role in the pathogenesis of gastroduodenal diseases (gastritis, gastric ulcer, duodenal ulcer, and gastric cancer. The Vero cell lines were found to be the most suitable form of tissue culture when compared with other cell lines used in our study for demonstrating the activity of H. pylori toxin.

  18. Transcriptional profiling of type II toxin-antitoxin genes of Helicobacter pylori under different environmental conditions: identification of HP0967-HP0968 system

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    MIGUEL A DE LA CRUZ

    2016-11-01

    Full Text Available Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and is responsible for causing peptic ulcers and gastric carcinoma. The expression of virulence factors allows the persistence of H. pylori in the stomach, which results in a chronic, sometimes uncontrolled inflammatory response. Type II toxin-antitoxin systems have emerged as important virulence factors in many pathogenic bacteria. Three type II toxin-antitoxin (TA systems have previously been identified in the genome of H. pylori 26695: HP0315-HP0316, HP0892-HP0893, and HP0894-HP0895. Here we characterized a heretofore undescribed type II TA system in H. pylori, HP0967-HP0968, which is encoded by the bicistronic operon hp0968-hp0967 and belongs to the Vap family. The predicted HP0967 protein is a toxin with ribonuclease activity whereas HP0968 is an antitoxin that binds to its own regulatory region. We found that all type II TA systems were expressed in H. pylori during early stationary growth phase, and differentially expressed in the presence of urea, nickel, and iron, although the hp0968-hp0967 pair was the most affected under these environmental conditions. Transcription of hp0968-hp0967 was strongly induced in a mature H. pylori biofilm and when the bacteria interacted with AGS epithelial cells. Kanamycin and chloramphenicol considerably boosted transcription levels of all the four type II TA systems. The hp0968-hp0967 TA system was the most frequent among 317 H. pylori strains isolated from all over the world. This study is the first report on the transcription of type II TA genes in H. pylori under different environmental conditions. Our data show that the HP0967 and HP0968 proteins constitute a bona fide type II TA system in H. pylori, whose expression is regulated by environmental cues, which are relevant in the context of infection of the human gastric mucosa.

  19. Pathogenesis of Helicobacter pylori infection.

    Science.gov (United States)

    Hofman, Paul; Waidner, Barbara; Hofman, Véronique; Bereswill, Stefan; Brest, Patrick; Kist, Manfred

    2004-01-01

    Research in the last year has provided new insights into the function of the the cag-associated type IV secretion system and the vacuolating toxin VacA. A quite new aspect was disclosed by the finding that Helicobacter pylori in Mongolian gerbils colonizes a very distinct topology in the gastric mucous layer, obviously providing optimal conditions for long-term survival. Further research activities focused on H. pylori ammonia and metal metabolism as well as on bacterial stress defence mechanisms. Differential expression of approximately 7% of the bacterial genome was found at low pH suggesting that H. pylori has evolved a multitude of acid-adaptive mechanisms. VacA was shown to interrupt phagosome maturation in macrophage cell lines as well as to modulate and interfere with T lymphocyte immunological functions. Gastric mucosa as well as the H. pylori-infected epithelial cell line AGS strongly express IL-8 receptor A and B, which might contribute to the augmentation of the inflammatory response. Accumulating evidence implicates genetic variation in the inflammatory response to H. pylori in the etiology of the increased risk of gastric cancer after H. pylori infection. The chronic imbalance between apoptosis and cell proliferation is the first step of gastric carcinogenesis. In this regard, it was demonstrated that coexpression of two H. pylori proteins, CagA and HspB, in AGS cells, caused an increase in E2F transcription factor, cyclin D3, and phosphorylated retinoblastoma protein. Taken together, we now have a better understanding of the role of different virulence factors of H. pylori. There is still a lot to be learned, but the promising discoveries summarized here, demonstrate that the investigation of the bacterial survival strategies will give novel insights into pathogenesis and disease development.

  20. Relationship between VacA Toxin and Host Cell Autophagy in Helicobacter pylori Infection of the Human Stomach: A Few Answers, Many Questions

    Directory of Open Access Journals (Sweden)

    Vittorio Ricci

    2016-07-01

    Full Text Available Helicobacter pylori is a Gram-negative bacterium that colonizes the stomach of about half the global population and represents the greatest risk factor for gastric malignancy. The relevance of H. pylori for gastric cancer development is equivalent to that of tobacco smoking for lung cancer. VacA toxin seems to play a pivotal role in the overall strategy of H. pylori towards achieving persistent gastric colonization. This strategy appears to involve the modulation of host cell autophagy. After an overview of autophagy and its role in infection and carcinogenesis, I critically review current knowledge about the action of VacA on host cell autophagy during H. pylori infection of the human stomach. Although VacA is a key player in modulation of H. pylori-induced autophagy, a few discrepancies in the data are also evident and many questions remain to be answered. We are thus still far from a definitive understanding of the molecular mechanisms through which VacA affects autophagy and the consequences of this toxin action on the overall pathogenic activity of H. pylori.

  1. Frequency of vacuolating cytotoxin A (VacA)-positive Helicobacter pylori seropositivity and TGF-β1 decrease in atrial fibrillation.

    Science.gov (United States)

    Ki, Mi-Ran; Shin, Dong-Gu; Park, Jong-Sun; Hong, Kyung-Sook; Hong, Il-Hwa; Park, Jin-Kyu; Jeong, Kyu-Shik

    2010-11-19

    The study was performed to determine whether there were any associations of VacA positive Helicobacter pylori and TGF-β1 with atrial fibrillation (AF). The serum levels of antibodies to H. pylori and VacA, and cytokines were assessed using ELISA in 96 subjects. While elevated levels of TNF-α, IL-6 and CRP were associated with AF, TGF-β(1) was significantly lowered in AF patients (p=0.021). In addition, AF was associated with elevated levels of antibodies to VacA (p=0.023), compared to the control group. Accordingly, the chronic infection of VacA(+)H. pylori may increase the risk for AF by inducing systemic inflammation mediated, partly by suppressed TGF-β(1) and elevated proinflammatory cytokines.

  2. Cycad toxins, Helicobacter pylori and parkinsonism: cholesterol glucosides as the common denomenator.

    Science.gov (United States)

    Schulz, J D; Hawkes, E L; Shaw, C A

    2006-01-01

    Understanding sporadic cases of age-dependent neurodegenerative diseases such as parkinsonism requires the evaluation of potential environmental factors. Amyotrophic lateral sclerosis-parkinsonism dementia complex (ALS-PDC), a neurological disorder in which features of parkinsonism are present and for which no consistent genetic explanation has been found, has been linked to the consumption of cycad (Cycas micronesica). Similarly, epidemiological evidence suggests an association between parkinsonism and gastric ulcer caused by Helicobacter pylori infection. While common immunological and inflammatory changes have been proposed to account for the link between parkinsonism and H. pylori infection, we propose an alternate explanation based on our work on the "cycad theory" of ALS-PDC. Recent experiments in our laboratory have identified several sterol glucosides in cycad that have neurotoxic properties in vitro and that appear to be linked to the development of neurodegenerative disease in vivo. Specifically, mice fed cycad display behavioural symptoms of parkinsonism such as reduced gait length, as well as neuropathological signs such as a loss of striatal dopaminergic (DAergic) terminals and an upregulation of the dopamine D2 receptor. These cycad-derived sterol glucosides are structurally similar to cholesterol glucosides that account for a significant part pf the lipid profile of H. pylori. We hypothesize that cholesterol glucosides arising from H. pylori infection may act as neurotoxins, promoting the degeneration of the DAergic neurons affected in parkinsonism, in a similar reaction to that which is thought to link cycad consumption and ALS-PDC. This hypothesis will be tested in future studies that will include exposing mice to purified sterol or cholestorol glucosides derived from cycad and comparing these mice behaviourally and neuropathologically to ones chronically infected with H. pylori.

  3. Toxins

    Science.gov (United States)

    Toxins are substances created by plants and animals that are poisonous to humans. Toxins also include some medicines that are helpful in small doses, but poisonous in large amounts. Most toxins that cause problems ...

  4. The Immunomodulator VacA Promotes Immune Tolerance and Persistent Helicobacter pylori Infection through Its Activities on T-Cells and Antigen-Presenting Cells

    Directory of Open Access Journals (Sweden)

    Aleksandra Djekic

    2016-06-01

    Full Text Available VacA is a pore-forming toxin that has long been known to induce vacuolization in gastric epithelial cells and to be linked to gastric disorders caused by H. pylori infection. Its role as a major colonization and persistence determinant of H. pylori is less well-understood. The purpose of this review is to discuss the various target cell types of VacA and its mechanism of action; specifically, we focus on the evidence showing that VacA targets myeloid cells and T-cells to directly and indirectly prevent H. pylori-specific T-cell responses and immune control of the infection. In particular, the ability of VacA-proficient H. pylori to skew T-cell responses towards regulatory T-cells and the effects of Tregs on H. pylori chronicity are highlighted. The by-stander effects of VacA-driven immunomodulation on extragastric diseases are discussed as well.

  5. Structural modifications of Helicobacter pylori lipopolysaccharide: An idea for how to live in peace

    Science.gov (United States)

    Chmiela, Magdalena; Miszczyk, Eliza; Rudnicka, Karolina

    2014-01-01

    In this review, we discuss the findings and concepts underlying the “persistence mechanisms” of Helicobacter pylori (H. pylori), a spiral-shaped, Gram-negative rod bacterium that was discovered as a gastric pathogen by Marshall and Warren in 1984. H. pylori colonizes the gastric mucosa of nearly half of the human population. Infections appear in early childhood and, if not treated, persist for life. The presence or absence of symptoms and their severity depend on multiple bacterial components, host susceptibility and environmental factors, which allow H. pylori to switch between pathogenicity and commensalism. Many studies have shown that H. pylori components may facilitate the colonization process and the immune response of the host during the course of H. pylori infection. These H. pylori-driven interactions might result from positive or negative modulation. Among the negative immunomodulators, a prominent position is occupied by a vacuolating toxin A (VacA) and cytotoxin-associated gene A (CagA) protein. However, in light of the recent studies that are presented in this review, it is necessary to enrich this panel with H. pylori lipopolysaccharide (LPS). Together with CagA and VacA, LPS suppresses the elimination of H. pylori bacteria from the gastric mucosa by interfering with the activity of innate and adaptive immune cells, diminishing the inflammatory response, and affecting the adaptive T lymphocyte response, thus facilitating the development of chronic infections. The complex strategy of H. pylori bacteria for survival in the gastric mucosa of the host involves both structural modifications of LPS lipid A to diminish its endotoxic properties and the expression and variation of Lewis determinants, arranged in O-specific chains of H. pylori LPS. By mimicking host components, this phenomenon leaves these bacteria “invisible” to immune cells. Together, these mechanisms allow H. pylori to survive and live for many years within their hosts. PMID:25110419

  6. Persistent colonization of Helicobacter pylori in human gut induces gastroduodenal diseases

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    Animesh Sarker

    2014-12-01

    Full Text Available Helicobacter pylori are gut bacteria colonize in the epithelial cell lining of the stomach and persist there for long du­ration. Around two-thirds of the world’s populations are infected with H. pylori and cause more than 90 percent of ulcers. The development of persistent inflammation is the main cause of chronic gastritis that finally results in a severe consequence known as stomach cancer. Two major virulence factors cytotoxin-associated gene product (cagA and the vacuolating toxin (vacA are mostly investigated as their close association with gastric carcinoma. In this review, host im­munity against H. pylori infection and their evasion mechanism are intensely explored. It is the fact, that understanding pin point molecular mechanisms of any infection is critical to develop novel strategies to prevent pertinent diseases. .J Microbiol Infect Dis 2014; 4(4: 170-176

  7. 幽门螺杆菌空泡毒素的研究新进展%Recent Advances in Helicobacter pylori Vacuolating Toxin

    Institute of Scientific and Technical Information of China (English)

    陶晶; 刘晶星

    2007-01-01

    幽门螺杆菌感染与慢性胃炎、消化性溃疡、胃黏膜相关淋巴组织淋巴瘤及胃腺癌等疾病的发生密切相关,WHO已将其列为Ⅰ类致癌因子.幽门螺杆菌的空泡毒素(VacA)在其致病性中起到重要作用.本文将对近几年有关幽门螺杆菌vacA基因型、VacA的致病机制和构建VacA突变体的研究进展作一综述.

  8. Sequence and apoptotic activity of VacA cytotoxin cloned from a Helicobacter pylori Thai clinical isolate.

    Science.gov (United States)

    Junaid, Muhammad; Al-Gubare, Sarbast; Yousef, Muhammad; Ubol, Mathukorn Na; Leetachewa, Somphob; Muanprasat, Chatchai; Angsuthanasombat, Chanan; Chaicumpa, Wanpen; Ali, Niaz; Katzenmeier, Gerd

    2014-01-01

    The vacuolating cytotoxin VacA produced by Helicobacter pylori induces the formation of large cytoplasmic vacuoles in host gastric epithelial cells as well as a release of cytochrome C from mitochondria resulting in cell apoptosis. Considerable sequence diversity in VacA relating to different degrees of disease severity is observed with clinical samples from a multitude of geographic places. In this study we describe expression in Escherichia coli, purification to homogeneity and in vitro assay of its apoptotic activity of a VacA toxin from a H. pylori isolate of a Thai patient with gastrointestinal lymphoma. Sequencing revealed that the deduced amino acid sequence of the cloned Thai isolate VacA is similar to H. pylori s1/m2 type strains. The percent sequence similarity to the model strain 60190 was lower due to the presence of extra amino acids in the mid (m) region. The purified VacA toxin exhibited significant apoptotic activity on both T84 and MDCK epithelial cell lines, as revealed by DAPI staining, whereby the observed activity was significantly higher on MDCK cells. These findings could relate to a modulation of VacA activity on host cells in the Thai isolate-VacA toxin that may differ from those of the model strain.

  9. Sequence and Apoptotic Activity of VacA Cytotoxin Cloned from a Helicobacter pylori Thai Clinical Isolate

    Directory of Open Access Journals (Sweden)

    Muhammad Junaid

    2014-01-01

    Full Text Available The vacuolating cytotoxin VacA produced by Helicobacter pylori induces the formation of large cytoplasmic vacuoles in host gastric epithelial cells as well as a release of cytochrome C from mitochondria resulting in cell apoptosis. Considerable sequence diversity in VacA relating to different degrees of disease severity is observed with clinical samples from a multitude of geographic places. In this study we describe expression in Escherichia coli, purification to homogeneity and in vitro assay of its apoptotic activity of a VacA toxin from a H. pylori isolate of a Thai patient with gastrointestinal lymphoma. Sequencing revealed that the deduced amino acid sequence of the cloned Thai isolate VacA is similar to H. pylori s1/m2 type strains. The percent sequence similarity to the model strain 60190 was lower due to the presence of extra amino acids in the mid (m region. The purified VacA toxin exhibited significant apoptotic activity on both T84 and MDCK epithelial cell lines, as revealed by DAPI staining, whereby the observed activity was significantly higher on MDCK cells. These findings could relate to a modulation of VacA activity on host cells in the Thai isolate-VacA toxin that may differ from those of the model strain.

  10. Helicobacter pylori infection: An overview of bacterial virulence factors and pathogenesis

    Directory of Open Access Journals (Sweden)

    Cheng-Yen Kao

    2016-02-01

    Full Text Available Helicobacter pylori pathogenesis and disease outcomes are mediated by a complex interplay between bacterial virulence factors, host, and environmental factors. After H. pylori enters the host stomach, four steps are critical for bacteria to establish successful colonization, persistent infection, and disease pathogenesis: (1 Survival in the acidic stomach; (2 movement toward epithelium cells by flagella-mediated motility; (3 attachment to host cells by adhesins/receptors interaction; (4 causing tissue damage by toxin release. Over the past 20 years, the understanding of H. pylori pathogenesis has been improved by studies focusing on the host and bacterial factors through epidemiology researches and molecular mechanism investigations. These include studies identifying the roles of novel virulence factors and their association with different disease outcomes, especially the bacterial adhesins, cag pathogenicity island, and vacuolating cytotoxin. Recently, the development of large-scale screening methods, including proteomic, and transcriptomic tools, has been used to determine the complex gene regulatory networks in H. pylori. In addition, a more available complete genomic database of H. pylori strains isolated from patients with different gastrointestinal diseases worldwide is helpful to characterize this bacterium. This review highlights the key findings of H. pylori virulence factors reported over the past 20 years.

  11. Serum-free culture of H pylori intensifies cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Hiroyuki Ohno; Akiyuki Murano

    2007-01-01

    AIM: To perform a long culture passage of H pylori without serum, taking into account its cytotoxicity and the presence of the probable new cytotoxic factor.METHODS: One sample of H pylori 60190 (ATCC49503) was grown on Brain Heart Infusion (BHI) agar containing 0.5% 2,6-di-O-methyl-β-cyclodextrin without any serum, being passaged 70-100 times every 3-4 d for approximately 2 h, while another sample of H pylori contained 70 mL/L fetal calf serum without 2,6-di-Omethyl-β-cyclodextrin. Their supernatant and extract after 16 h in culture were evaluated for changes in cell morphology and for cell viability using HeLa cells. Furthermore, the characteristics of the probable cytotoxic factor in the extract were examined on partial purification studies and its cytotoxicity was evaluated in various human cells.RESULTS: The supernatant and the extract of the bacterium grown on serum-free medium had strong cytotoxicity compared with those grown on serumcontaining medium. They irreversibly damaged HeLa cells without vacuolation that was altogether different from that of the bacterium when grown with serum.Their cytotoxicity was easily measured by cell viability assay. The probable cytotoxic factor partially purified and detected by chromatography had characteristics difference from that of vacuolating toxin and a broad cytotoxicity toward various cell lines.CONCLUSION: Serum-free long culture method of H pylori makes its supematant and its extract cytotoxic enough to be easily measured by cell viability assay. The probable cytotoxic factor has a unique characteristic and might be a new cytotoxin.

  12. Sphingomyelin functions as a novel receptor for Helicobacter pylori VacA.

    Directory of Open Access Journals (Sweden)

    Vijay R Gupta

    2008-05-01

    Full Text Available The vacuolating cytotoxin (VacA of the gastric pathogen Helicobacter pylori binds and enters epithelial cells, ultimately resulting in cellular vacuolation. Several host factors have been reported to be important for VacA function, but none of these have been demonstrated to be essential for toxin binding to the plasma membrane. Thus, the identity of cell surface receptors critical for both toxin binding and function has remained elusive. Here, we identify VacA as the first bacterial virulence factor that exploits the important plasma membrane sphingolipid, sphingomyelin (SM, as a cellular receptor. Depletion of plasma membrane SM with sphingomyelinase inhibited VacA-mediated vacuolation and significantly reduced the sensitivity of HeLa cells, as well as several other cell lines, to VacA. Further analysis revealed that SM is critical for VacA interactions with the plasma membrane. Restoring plasma membrane SM in cells previously depleted of SM was sufficient to rescue both toxin vacuolation activity and plasma membrane binding. VacA association with detergent-resistant membranes was inhibited in cells pretreated with SMase C, indicating the importance of SM for VacA association with lipid raft microdomains. Finally, VacA bound to SM in an in vitro ELISA assay in a manner competitively inhibited by lysenin, a known SM-binding protein. Our results suggest a model where VacA may exploit the capacity of SM to preferentially partition into lipid rafts in order to access the raft-associated cellular machinery previously shown to be required for toxin entry into host cells.

  13. Effect of honokiol on Helicobacter pylori growth and the expression and activity of vacuolating cytotoxin A%和厚朴酚对幽门螺杆菌生长和空泡毒素A表达及活性的影响

    Institute of Scientific and Technical Information of China (English)

    刘丹; 廖顺花; 王莉新; 王易

    2013-01-01

    [目的]幽门螺杆菌(Helicobacter pylori,H.pylori)是胃炎和消化性溃疡的病原体,但其具有潜在的正常菌群的特性.本研究通过评价临床常用中药厚朴的活性成分和厚朴酚对H.pylori的抑制作用及对其空泡毒素A表达和活性的影响,以反映其对H.pylori具有的潜在去除毒性的作用.[方法]使用平皿稀释固体法和脑心浸液液体法测定和厚朴酚对H.pylori的最低抑菌浓度,进一步通过中性红摄入法评价经无抑菌效果的低浓度和厚朴酚干预后,H.pylori培养上清中空泡毒素A(Vacuolating cytotoxin A,VacA)的毒性作用;并通过RT-PCR和Western blot方法检测经低浓度和厚朴酚处理后,H.pylori菌体及分泌上清中VacA mRNA和蛋白的表达水平.[结果]发现高浓度(0.75 g/L)和厚朴酚对H.pylori具有抑制作用;而在远低于最低抑菌浓度时,和厚朴酚可有效抑制H.pylori VacA的形成和分泌.[结论]和厚朴酚具有下调H.pylori毒性的潜在作用,这为基于“致病性H.pylori的非致病性转变”这一机理的干预性治疗提供了有希望的研究前景.

  14. Construction and identification of the eukaryotic expression vector for gene encoding the vacuolating cytotoxin of Helicobacter pylori and observations on the induction of macrophage vacuole formation and apoptosis%幽门螺杆菌VacA N端真核表达载体的构建、鉴定及其诱导巨噬细胞空泡化和凋亡的观察

    Institute of Scientific and Technical Information of China (English)

    黎村艳; 张艳; 刘志杰; 余敏君; 于文

    2008-01-01

    目的 构建幽门螺杆菌(Helicobacter pylori,HP)空泡毒素(Vacuolating cytotoxin,VacA)基因的真核表达载体pDsRed-Monomer-C1/vacA,并在THP-1巨噬细胞中表达,为研究VacA单一毒力决定簇的致病性奠定实验基础.方法 用Primer 5.0软件设计引物,以HP基因组为模板,PCR扩增vacA目的基因片段,克隆入真核表达载体pDsRed-Monomer-C1中,经酶切、PCR鉴定及测序鉴定后,转染 THP-1巨噬细胞中,荧光显微镜和Western-blot检测VacA蛋白在细胞中的表达;电镜观察巨噬细胞(MΦ)的空泡样变和凋亡;流式细胞仪检测细胞的凋亡率.结果 PCR扩增得到了大小约为1 428bp的目的片段,双酶切及测序鉴定证明成功构建了HP真核表达重组载体;转染后24h,重组质粒组部分细胞中有聚集的荧光颗粒,部分细胞发生空泡样变和凋亡改变;细胞凋亡率明显高于空质粒组和阴性对照组(P<0.001),细胞核因子-κB(nuclear factor kappaB,NF-κB)的抑制剂二硫代氨基甲酸吡咯烷(pyrrolidine dithiocarbamate,PDTC)抑制细胞的凋亡.结论 VacA蛋白瞬时高表达促进THP-1巨噬细胞空泡样变和凋亡.NF-κB可能参与调节VacA诱导的巨噬细胞凋亡.

  15. Helicobacter pylori VacA suppresses Lactobacillus acidophilus-induced interferon beta signaling in macrophages via alterations in the endocytic pathway.

    Science.gov (United States)

    Weiss, Gudrun; Forster, Sam; Irving, Aaron; Tate, Michelle; Ferrero, Richard L; Hertzog, Paul; Frøkiær, Hanne; Kaparakis-Liaskos, Maria

    2013-06-11

    Helicobacter pylori causes chronic gastritis and avoids elimination by the immune system of the infected host. The commensal bacterium Lactobacillus acidophilus has been suggested to exert beneficial effects as a supplement during H. pylori eradication therapy. In the present study, we applied whole-genome microarray analysis to compare the immune responses induced in murine bone marrow-derived macrophages (BMDMs) stimulated with L. acidophilus, H. pylori, or both bacteria in combination. While L. acidophilus induced a Th1-polarizing response characterized by high expression of interferon beta (IFN-β) and interleukin 12 (IL-12), H. pylori strongly induced the innate cytokines IL-1β and IL-1α. In BMDMs prestimulated with L. acidophilus, H. pylori blocked the expression of L. acidophilus-induced IFN-β and IL-12 and suppressed the expression of key regulators of the Rho, Rac, and Cdc42 GTPases. The inhibition of L. acidophilus-induced IFN-β was independent of H. pylori viability and the virulence factor CagPAI; however, a vacuolating cytotoxin (vacA) mutant was unable to block IFN-β. Confocal microscopy demonstrated that the addition of H. pylori to L. acidophilus-stimulated BMDMs redirects intracellular processing, leading to an accumulation of L. acidophilus in the endosomal and lysosomal compartments. Thus, our findings indicate that H. pylori inhibits the development of a strong Th1-polarizing response in BMDMs stimulated with L. acidophilus by blocking the production of IFN-β in a VacA-dependent manner. We suggest that this abrogation is caused by a redirection of the endocytotic pathway in the processing of L. acidophilus. IMPORTANCE Approximately half of the world's population is infected with Helicobacter pylori. The factors that allow this pathogen to persist in the stomach and cause chronic infections have not yet been fully elucidated. In particular, how H. pylori avoids killing by macrophages, one of the main types of immune cell underlying the

  16. The Effect of Helicobacter Pylori Vacuolating Cytotoxin A(VacA) on Platelet Functions%幽门螺杆菌空胞毒素对血小板功能的影响

    Institute of Scientific and Technical Information of China (English)

    林香春; 佐藤金夫; 尾崎由基男

    2009-01-01

    目的 探讨幽门螺杆菌(H pylori)空胞毒素(VacA)对血小板功能的影响.方法 健康志愿者全血分离血小板,用不同浓度的VacA刺激血小板,用热灭活VacA作为对照组,观察血小板表面P-选择素的表达;采用低剂量vWF和Botrocetin刺激上述两组血小板,观察VacA对血小板凝集功能的影响.结果 与对照组比较,VacA可以引起血小板表面P-选择素表达增加;增强血小板对vWF和Botrocetin刺激的凝集反应.结论 VacA直接作用于血小板并引起血小板的活化.

  17. Toward the development of a stable, freeze-dried formulation of Helicobacter pylori killed whole cell vaccine adjuvanted with a novel mutant of Escherichia coli heat-labile toxin.

    Science.gov (United States)

    Summerton, Nancy A; Welch, Richard W; Bondoc, Laureano; Yang, Huei-Hsiung; Pleune, Brett; Ramachandran, Naryaswamy; Harris, Andrea M; Bland, Desiree; Jackson, W James; Park, Sukjoon; Clements, John D; Nabors, Gary S

    2010-02-03

    No vaccine exists for the prevention of infection with the ubiquitous gastric pathogen Helicobacter pylori, and drug therapy for the infection is complicated by poor patient compliance, the high cost of treatment, and ineffectiveness against drug-resistant strains. A new medical advancement is required to reduce the incidence of peptic ulcer disease and stomach cancer, two conditions caused by infection with H. pylori. Clinical trials have been performed with a formalin-inactivated H. pylori whole cell (HWC) vaccine, given orally in combination with the mucosal adjuvant mLT(R192G), a mutant of Escherichia coli heat-labile toxin. Following the initial dose of this vaccine, some subjects experienced gastrointestinal side effects. To reduce side effects and potentially further increase the amount of adjuvant that can safely be administered with the HWC vaccine, experiments were performed with a form of LT that carried two mutations in the A subunit, a substitution of G for R at position 192, and A for L at position 211. The double mutant LT (dmLT) adjuvant stimulated immune responses as effectively as the single mutant LT in mice. Additionally, following a challenge infection, the dmLT-adjuvanted vaccine was as effective as single mutant LT in reducing gastric urease levels (diagnostic for H. pylori infection), and H. pylori colonization in the stomach as assessed by quantitative analysis of stomach homogenates. A lyophilized formulation of HWC was developed to improve stability and to potentially reduce reliance on cold chain maintenance. It was observed that a dmLT-adjuvanted lyophilized vaccine was equally as protective in the mouse model as the liquid formulation as assessed by gastric urease analysis and analysis of stomach homogenates for viable H. pylori. No readily detectable effect of tonicity or moisture content was observed for the lyophilized vaccine within the formulation limits evaluated. In an accelerated stability study performed at 37 degrees C the

  18. Helicobacter pylori induces miR-155 in T cells in a cAMP-Foxp3-dependent manner.

    Directory of Open Access Journals (Sweden)

    Lina Fassi Fehri

    Full Text Available Amongst the most severe clinical outcomes of life-long infections with Helicobacter pylori is the development of peptic ulcers and gastric adenocarcinoma--diseases often associated with an increase of regulatory T cells. Understanding H. pylori-driven regulation of T cells is therefore of crucial clinical importance. Several studies have defined mammalian microRNAs as key regulators of the immune system and of carcinogenic processes. Hence, we aimed here to identify H. pylori-regulated miRNAs, mainly in human T cells. MicroRNA profiling of non-infected and infected human T cells revealed H. pylori infection triggers miR-155 expression in vitro and in vivo. By using single and double H. pylori mutants and the corresponding purified enzymes, the bacterial vacuolating toxin A (VacA and gamma-glutamyl transpeptidase (GGT plus lipopolysaccharide (LPS tested positive for their ability to regulate miR-155 and Foxp3 expression in human lymphocytes; the latter being considered as the master regulator and marker of regulatory T cells. RNAi-mediated knockdown (KD of the Foxp3 transcription factor in T cells abolished miR-155 expression. Using adenylate cyclase inhibitors, the miR-155 induction cascade was shown to be dependent on the second messenger cyclic adenosine monophosphate (cAMP. Furthermore, we found that miR-155 directly targets the protein kinase A inhibitor alpha (PKIalpha mRNA in its 3'UTR, indicative of a positive feedback mechanism on the cAMP pathway. Taken together, our study describes, in the context of an H. pylori infection, a direct link between Foxp3 and miR-155 in human T cells and highlights the significance of cAMP in this miR-155 induction cascade.

  19. Clustering of Helicobacter pylori VacA in lipid rafts, mediated by its receptor, receptor-like protein tyrosine phosphatase beta, is required for intoxication in AZ-521 Cells

    DEFF Research Database (Denmark)

    Nakayama, Masaaki; Hisatsune, Jyunzo; Yamasaki, Eiki;

    2006-01-01

    Helicobacter pylori vacuolating cytotoxin, VacA, induces multiple effects on epithelial cells through different cellular events: one involves pore formation, leading to vacuolation, mitochondrial damage, and apoptosis, and the second involves cell signaling, resulting in stimulation of proinflamm......Helicobacter pylori vacuolating cytotoxin, VacA, induces multiple effects on epithelial cells through different cellular events: one involves pore formation, leading to vacuolation, mitochondrial damage, and apoptosis, and the second involves cell signaling, resulting in stimulation...

  20. Pathogenesis of Helicobacter pylori infection

    Science.gov (United States)

    Sgouras, Dionyssios N.; Trang, Tran Thi Huyen; Yamaoka, Yoshio

    2015-01-01

    Three decades have passed since Warren and Marshall described the successful isolation and culture of Helicobacter pylori, the Gram-negative bacterium that colonizes the stomach of half the human population worldwide. Although it is documented that H. pylori infection is implicated in a range of disorders of the upper gastrointestinal tract, as well as associated organs, many aspects relating to host colonization, successful persistence and the pathophysiological mechanisms of this bacteria still remain controversial and are constantly being explored. Unceasing efforts to decipher the pathophysiology of H. pylori infection have illuminated the crucially important contribution of multifarious bacterial factors for H. pylori pathogenesis, in particular the cag pathogenicity island (PAI), the effector protein CagA and the vacuolating cytotoxin VacA. In addition, recent studies have provided insight into the importance of the gastrointestinal microbiota on the cumulative pathophysiology associated with H. pylori infections. This review focuses on the key findings of publications related to the pathogenesis of H. pylori infection published during the last year, with an emphasis on factors affecting colonization efficiency, cag PAI, CagA, VacA and gastrointestinal microbiota. PMID:26372819

  1. Medicinal plant activity on Helicobacter pylori related diseases

    Science.gov (United States)

    Wang, Yuan-Chuen

    2014-01-01

    More than 50% of the world population is infected with Helicobacter pylori (H. pylori). The bacterium highly links to peptic ulcer diseases and duodenal ulcer, which was classified as a group I carcinogen in 1994 by the WHO. The pathogenesis of H. pylori is contributed by its virulence factors including urease, flagella, vacuolating cytotoxin A (VacA), cytotoxin-associated gene antigen (Cag A), and others. Of those virulence factors, VacA and CagA play the key roles. Infection with H. pylori vacA-positive strains can lead to vacuolation and apoptosis, whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer. Numerous medicinal plants have been reported for their anti-H. pylori activity, and the relevant active compounds including polyphenols, flavonoids, quinones, coumarins, terpenoids, and alkaloids have been studied. The anti-H. pylori action mechanisms, including inhibition of enzymatic (urease, DNA gyrase, dihydrofolate reductase, N-acetyltransferase, and myeloperoxidase) and adhesive activities, high redox potential, and hydrophilic/hydrophobic natures of compounds, have also been discussed in detail. H. pylori-induced gastric inflammation may progress to superficial gastritis, atrophic gastritis, and finally gastric cancer. Many natural products have anti-H. pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-κB and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress. Anti-H. pylori induced gastric inflammatory effects of plant products, including quercetin, apigenin, carotenoids-rich algae, tea product, garlic extract, apple peel polyphenol, and finger-root extract, have been documented. In conclusion, many medicinal plant products possess anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect. Those plant products have showed great potential as pharmaceutical candidates for H. pylori

  2. cagA and vacA genotype of Helicobacter pylori associated with gastric diseases in Xi'an area

    Institute of Scientific and Technical Information of China (English)

    Wen Qiao; Jia-Lu Hu; Bing Xiao; Kai-Chun Wu; Dao-Rong Peng; John C Atherton; Hui Xue

    2003-01-01

    AIM: To establish stock of clinical Helicobacter pylori (H.pylon) isolates, to perform cagA and vacA typing of these isolates, to evaluate the relationship between genotypes of cagA and vacA and upper gastrointestinal diseases and to assess the association of vacA genotypes with presence of the pathogenicity marker-cagA.METHODS: Clinical H.pylori strains were isolated from the antrum of 259 patients in Clumbia agar. The isolated H.pylori strains were identified by histology, and16SrRNA PCR.CagA genotypes were detected by colony hybridization, the probe was derived from the cloned plasmid PcagA, and digested by EcoRI-HindⅢ and the isolated PcagA DNA fragment was radioactively labelled by the random priming method. vacA genes types (s,m)and subtypes (s1a, s1b,s2) were typed by PCR. Vacuolating toxin was detected with neutral red absorb test. The results were treated statistically by χ2test, ttest, and rank sum test.RESULTS: A total of 192 clinical H. pylori strains were isolated and the stock of Helicobacter pylori was established. The total positive rate of cagA was 87 % in all gastric diseases,and 95 % in gastric cancer group. There was a difference between gastric cancer group and the other groups (P<0.05)except duodenal ulcer group. The expression of type s1 of vacA was more than type s2 (P<0.05), and, the expression of type m1 was equal to type m2. In gastric cancer group,there was a difference between s1a and s1b (P<0.05), and s1a was more than s1b. Vacuolating toxins were more in Xi′an area isolates.CONCLUSION: The cagA+ vacA type s1 clinical isolates are more in Xi′an area, but this can not serve as an index to predict gastric cancer.

  3. 幽门螺杆菌VacA蛋白体外诱导胃上皮AGS细胞内HMGB1的表达%HMGB1 expression in gastric epithelial AGS cells in vitro induced by vacuolating cytotoxin of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    赵琪; 郭继中; 黄学文; 陈国千; 罗瑞华; 黄丽丽; 安仙园; 赵兰静

    2011-01-01

    目的 探讨幽门螺杆菌(HP)感染的胃上皮AGS细胞内高迁移率族蛋白B1(high mobbility group box 1,HMGB1)的表达.方法 Hpl1638(CagA+,VacA+)和Hp1638突变株(Hp1638M,CagA+,VacA-)的提取液与AGS细胞共同温育后,收集细胞及培养上清液.裂解AGS细胞,western blot分析AGS细胞内HMGB1的表达,ELISA法检测培养上清液中HMGB1的水平.结果 HpLL638提取液刺激AGS细胞后HMGB1表达量为(123.33±25.2)μg/mL,明显高于Hpll638M提取液刺激后的(46.67±7.23)μg/mL(q=8.49,P<0.01).Hp11638和Hp11638M提取液刺激的AGS细胞培养上清液中HMGB1的水平分别为(115.59±16.62)和(48.32±6.30)ng/mL,差异有统计学意义(q=12.25,P<0.01).结论 在胃炎发生、发展过程中,VacA蛋白是刺激细胞中HMGB1高表达的主要因子.%Objective To explore the expression of high mobility group box 1 (HMGB1) in gastric epithelial AGS cells infected by He-licobacter pylori (HP). Methods Both the extracts of Hp11638 strain, which was positively expressed cytotoxin-associated protein (CagA) and vacuolating cytotoxin (VacA) , and Hp] 1638 mutant strain (Hp11638M, CagA+ , VacA- ) were incubated with AGS cells respectively. The AGS cells and the supernatant were collected. The AGS cells were splitted to analyze the expression of HMGB1 by west-em blotting, and the level of HMGB1 in the supernatant was measured by ELISA. Results The content of HMGB1 in AGS cells infected by extracts of Hp11638 was (123.3 ±25.2) μg/mL, which was significantly higher than that of Hpll638M (46.67 ±7.23) μg/mL, q = 8.49, P <0.01. The level of HMGB1 in the culture supernatant infected by the extracts of Hpl 1638 was (115.59 ± 16. 62 ) ng/mL which was significantly higher than that of Hpll638M (48.32±6.30) ng/mL, q = 12. 25, P <0. 01. Conclusions During the development and advance of gastritis, vacuolating cytotoxin may be the main factor for stimulating AGS cells to highly express HMGB1 protein.

  4. Expression, purification and immuno-characteristics of recombination UreB protein of H.pylori

    Institute of Scientific and Technical Information of China (English)

    Chao Wu; Quan Ming Zou; Hong Guo; Xiao Peng Yuan; Wei Jun Zhang; Dong Shui Lu; Xu Hu Mao

    2001-01-01

    @@ INTRODUCTION Helicobacter pylori (H . pylori) is associated with the development of chronic gastritis ,peptic ulcer and gastric cancer and gastric MALT lymphoma[1-9],H .pylori has many antigens ,including urease ,heat shock protein and vacuolating cytotoxin and so on ,and urease is an important factor in the colinization of the gastric mucosa and suspected to cause damage to the gastric mucosa[10-14].At the same time ,urdase is also one of the important protective antigens .

  5. MicroRNA-3178 ameliorates inflammation and gastric carcinogenesis promoted by Helicobacter pylori new toxin, Tip-α, by targeting TRAF3.

    Science.gov (United States)

    Zou, Meijuan; Wang, Fang; Jiang, Aiqin; Xia, Anliang; Kong, Siya; Gong, Chun; Zhu, Mingxia; Zhou, Xin; Zhu, Jun; Zhu, Wei; Cheng, Wenfang

    2017-04-01

    Helicobacter pylori infection is the main cause of chronic gastritis, peptic ulcer, and gastric cancer. Tip-α is a newly identified carcinogenic factor present in H. pylori. TRAF3 can activate NF-κB by both canonical and noncanonical signaling pathways. In this study, we found that the expression of TRAF3 and NF-κB was upregulated, while microRNA-3178 (miR-3178) was decreased in H. pylori-positive gastric tissues but not in H. pylori-negative tissues. GES-1 cells were incubated with 12.5 μg/mL recombinant Tip-α (rTip-α) in RPMI1640 for 2 hours. After another 24 hours, the supernatant medium was designed as inflammatory-conditioned medium (ICM) and that from the untreated control cells was designed as untreated control medium. The release of proinflammatory cytokines from GES-1 cells and proliferation of gastric cancer cells was determined by ELISA and CCK-8 kits. Cells were transfected with the mimic, inhibitor, negative control of miR-3178, or TRAF3 siRNA control siRNA. The medium was then replaced with RPMI1640, 12.5 μg/mL rTip-α, and collected, and the total cellular RNA and protein were extracted for the following detection. MiR-3178 mimic prevented the increasement of TRAF3 and hence decreased activation of NF-κB signals, whereas miR-3178 inhibitor could not, in GES-1 cells with Tip-α treatment. The condition medium from miR-3178 mimic transfected GES-1 cells could inhibit proliferation and induce apoptosis of inflammation-related gastric cancer cells SGC7901 and MGC803 by decreasing the production of inflammatory cytokines TNF-α and IL-6, which were secreted by GES-1 cells. Taken all together, Tip-α might activate NF-κB to promote inflammation and carcinogenesis by inhibiting miR-3178 expression, which directly targeting TRAF3, during H. pylori infection in gastric mucosal epithelial cells. © 2016 John Wiley & Sons Ltd.

  6. Helicobacter pylori

    OpenAIRE

    BATESON, M

    2000-01-01

    Helicobacter pylori infection is a major cause of peptic ulcer disease, and its detection and eradication are now an important part of gastroenterology. Effective regimes are available which will eliminate the organism in about 90% of cases in developed countries.


Keywords: Helicobacter pylori

  7. Pathogenesis of helicobacter pylori infection: Bacterium and host relationship

    Directory of Open Access Journals (Sweden)

    Sokić-Milutinović Aleksandra

    2004-01-01

    Full Text Available Helicobacter pylori (H. pylori colonizes the gastric mucosa of a half of the mankind. Duodenal ulcer is found in 15-25%, t gastric ulcer in 13%, while gastric adenocarcinoma develops in 1% of all infected individuals. Pathogenesis of H. pylori infection is related to the virulence factors of the bacterium, environmental (dietary habits, hygiene, stress and host factors (age, sex, blood type. Colonization of the gastric mucosa is related to the motility of the bacterium, presence of lipopolysacharide (LPS and various bacterial enzymes. Gastric mucosal injury is the result of H. pylori LPS, vacuolization cytotoxin (vacA, cytotoxin associated protein (cagA, heat shock proteins and factors responsible for neutrophil chemotaxis and activity. H. pylori colonizes the gastric mucosa and zones of ectopic gastric epithelium. H. pylori infection is transmitted via oral-oral, fecal-oral and iatrogenic way (during endoscopy. Higher prevalence of the infection is associated with lower socioeconomic level, lack of drinking water, and living in a community. Acute H. pylori gastritis is superficial pangastritis progressing into the chronic phase after 7-10 days. Gastric mucosal atrophy and intestinal metaplasia can develop during the course of H. pylori infection. Clearly defined factors that influence the outcome of H. pylori infection include bacterial strain, distribution of gastritis, acid secretion and gastric mucosal atrophy.

  8. HELICOBACTER PYLORI

    Science.gov (United States)

    Helicobacter pylori is a pathogenic bacteria which inhabits the human stomach and upper gastrointestinal tract. This encyclopedic entry summarizes the potential role of this organism as a waterborne pathogen. Information is provided on the physiology and morphology of this bacter...

  9. HELICOBACTER PYLORI

    Science.gov (United States)

    Helicobacter pylori is a pathogenic bacteria which inhabits the human stomach and upper gastrointestinal tract. This encyclopedic entry summarizes the potential role of this organism as a waterborne pathogen. Information is provided on the physiology and morphology of this bacter...

  10. Helicobacter pylori Test

    Science.gov (United States)

    ... urease test (RUT) for H. pylori Formal name: Helicobacter pylori Related tests: Gastrin At a Glance Test Sample ... else I should know? How is it used? Helicobacter pylori testing is used to diagnose an infection due ...

  11. Protein dynamics and proteolysis in plant vacuoles.

    Science.gov (United States)

    Müntz, Klaus

    2007-01-01

    Plant cells cannot live without their vacuoles. The tissues and organs of a plant contain a wide variety of differentiated and specialized vacuoles -- even a single plant cell can possess two or more types of vacuoles. Vacuolar proteins are encoded by nuclear genes and synthesized in the cytoplasm. Their transport into the vacuolar compartment is under cytoplasmic control. Transcription seems to be a major control level for differential protein supply to the vacuoles. It is at this level that vacuole differentiation and functions are mainly integrated into cellular processes. Recycling amino acids generated by protein degradation is a major function of the vacuole. This is most evident when storage proteins are mobilized in storage tissues of generative or vegetative organs in order to nourish the embryo of germinating seeds or sprouting buds. When specific proteins are transferred to the vacuole for immediate degradation this compartment contributes to the adaptation of protein complexes in response to changes in developmental or environmental conditions. Vacuolar proteases are involved in protein degradation during reversible senescence and programmed cell death, which is also called irreversible senescence. Vacuoles contribute to defence against pathogens and herbivores by limited and unlimited proteolysis. Our present knowledge on functions and processes of vacuolar protein dynamics in plants is reviewed. Research perspectives are deduced.

  12. Helicobacter pylori HP0231 Influences Bacterial Virulence and Is Essential for Gastric Colonization.

    Directory of Open Access Journals (Sweden)

    Yu Zhong

    Full Text Available The Dsb protein family is responsible for introducing disulfide bonds into nascent proteins in prokaryotes, stabilizing the structure of many proteins. Helicobacter pylori HP0231 is a Dsb-like protein, shown to catalyze disulfide bond formation and to participate in redox homeostasis. Notably, many H. pylori virulence factors are stabilized by the formation of disulfide bonds. By employing H. pylori HP0231 deficient strains we analyzed the effect of lack of this bacterial protein on the functionality of virulence factors containing putative disulfide bonds. The lack of H. pylori HP0231 impaired CagA translocation into gastric epithelial cells and reduced VacA-induced cellular vacuolation. Moreover, H. pylori HP0231 deficient bacteria were not able to colonize the gastric mucosa of mice, probably due to compromised motility. Together, our data demonstrate an essential function for H. pylori HP0231 in gastric colonization and proper function of bacterial virulence factors related to gastric pathology.

  13. Vibrio cholerae O1 Strains of Different Ribotypes have Similar hlyA RFLP Patterns but Different Vacuolating Ability

    Directory of Open Access Journals (Sweden)

    Jorge E. Vidal

    2007-01-01

    Full Text Available Extensive cytoplasmic vacuolation on Vero and HeLa cells in vitro by the Vibrio cholerae pore forming toxin HlyA, has been previously reported by our group. Vibrio cholerae O1 and non-O1 pathogenic strains show differences in the potential to induce vacuolation, here we study occurring variations on vacuolating cytotoxic ability, related to changes in the nucleotide sequence of the hlyA-orf. A collection of eight toxigenic strains of V. cholerae O1 El Tor and a non-toxigenic one, all belonging to different ribotypes was tested for their vacuolating ability, and hlyA-orf similarity based on PCR and RFLPs. The strains had extremely different vacuolating capacities, those from the ribotype 2 isolated from the US Gulf Coast, showed the highest vacuolating titer (10240 dil, and the rest of the collection had considerably lower titers ranging among 40 to 360 dilutions. PCR of hlyA-orf, was performed and RFLPs were generated using seven restriction enzymes, this approach later revealed small changes of restriction maps, among the strains. The phenogram constructed from the RFLPs, showed two major branches, one of them included most of the strains, the other separates the only Mexican wild type non-O1 Vibrio cholerae. To test for vacuolating ability out of the Vibrio genetic context, the amplified hlyA-orfs from the collection of strains were cloned in pGEMT- vector system and supernatants from the recombinant E coli DH5-, showed no differences on vacuolating titers, the clones always were low producers. Results from the cloning, together with those from the phenogram indicated that the hlyA gene is mainly conserved and the differences on vacuolating activity are unrelated to minute changes seen in the hlyA-orf. Production of high vacuolating titers on Vibrio strains could be due to transcriptional regulation. Whether the high vacuolating titer would be related to increased virulence, is still to be found.

  14. Calcium Signals from the Vacuole

    Directory of Open Access Journals (Sweden)

    Gerald Schönknecht

    2013-10-01

    Full Text Available The vacuole is by far the largest intracellular Ca2+ store in most plant cells. Here, the current knowledge about the molecular mechanisms of vacuolar Ca2+ release and Ca2+ uptake is summarized, and how different vacuolar Ca2+ channels and Ca2+ pumps may contribute to Ca2+ signaling in plant cells is discussed. To provide a phylogenetic perspective, the distribution of potential vacuolar Ca2+ transporters is compared for different clades of photosynthetic eukaryotes. There are several candidates for vacuolar Ca2+ channels that could elicit cytosolic [Ca2+] transients. Typical second messengers, such as InsP3 and cADPR, seem to trigger vacuolar Ca2+ release, but the molecular mechanism of this Ca2+ release still awaits elucidation. Some vacuolar Ca2+ channels have been identified on a molecular level, the voltage-dependent SV/TPC1 channel, and recently two cyclic-nucleotide-gated cation channels. However, their function in Ca2+ signaling still has to be demonstrated. Ca2+ pumps in addition to establishing long-term Ca2+ homeostasis can shape cytosolic [Ca2+] transients by limiting their amplitude and duration, and may thus affect Ca2+ signaling.

  15. Helicobacter pylori impairs murine dendritic cell responses to infection.

    Directory of Open Access Journals (Sweden)

    Ya-Hui Wang

    Full Text Available BACKGROUND: Helicobacter pylori, a human pathogen associated with chronic gastritis, peptic ulcer and gastric malignancies, is generally viewed as an extracellular microorganism. Here, we show that H. pylori replicates in murine bone marrow derived-dendritic cells (BMDCs within autophagosomes. METHODOLOGY/PRINCIPAL FINDINGS: A 10-fold increase of CFU is found between 2 h and 6 h p.i. in H. pylori-infected BMDCs. Autophagy is induced around the bacterium and participates at late time points of infection for the clearance of intracellular H. pylori. As a consequence of infection, LC3, LAMP1 and MHC class II molecules are retained within the H. pylori-containing vacuoles and export of MHC class II molecules to cell surface is blocked. However, formalin-fixed H. pylori still maintain this inhibitory activity in BMDC derived from wild type mice, but not in from either TLR4 or TLR2-deficient mice, suggesting the involvement of H. pylori-LPS in this process. TNF-alpha, IL-6 and IL-10 expression was also modulated upon infection showing a TLR2-specific dependent IL-10 secretion. No IL-12 was detected favoring the hypothesis of a down modulation of DC functions during H. pylori infection. Furthermore, antigen-specific T cells proliferation was also impaired upon infection. CONCLUSIONS/SIGNIFICANCE: H. pylori can infect and replicate in BMDCs and thereby affects DC-mediated immune responses. The implication of this new finding is discussed for the biological life cycle of H. pylori in the host.

  16. Pathogenic diversity of Helicobacter pylori.

    Science.gov (United States)

    Mégraud, F

    1997-04-01

    Helicobacter pylori has been shown to possess a very heterogeneous genoma despite its common phenotypic properties. Some characteristics relevant to pathogenesis have also been found to be heterogeneous. This is the case for adherence properties and the amount of urease produced, but it was not possible to relate these properties to disease entities. A vacuolating cytotoxin which alters epithelial cells has been found in about 60% of strains isolated from patients with ulcers versus 30% from those with gastritis only. The cagA gene can be used as a marker to detect the cag pathogenicity island. This DNA fragment seems to induce an increased inflammation in the gastric tissue via release of interleukin 8 by the epithelial cells. The association of this marker is strongly linked with ulcers compared with gastritis only (80% vs 55%, respectively). A number of other properties may be heterogeneous, but the low number of strains studied does not allow conclusions to be drawn.

  17. Stool C difficile toxin

    Science.gov (United States)

    ... toxin; Colitis - toxin; Pseudomembranous - toxin; Necrotizing colitis - toxin; C difficile - toxin ... be analyzed. There are several ways to detect C difficile toxin in the stool sample. Enzyme immunoassay ( ...

  18. Helicobacter pylori virulence and cancer pathogenesis.

    Science.gov (United States)

    Yamaoka, Yoshio; Graham, David Y

    2014-06-01

    Helicobacter pylori is human gastric pathogen that causes chronic and progressive gastric mucosal inflammation and is responsible for the gastric inflammation-associated diseases, gastric cancer and peptic ulcer disease. Specific outcomes reflect the interplay between host-, environmental- and bacterial-specific factors. Progress in understanding putative virulence factors in disease pathogenesis has been limited and many false leads have consumed scarce resources. Few in vitro-in vivo correlations or translational applications have proved clinically relevant. Reported virulence factor-related outcomes reflect differences in relative risk of disease rather than specificity for any specific outcome. Studies of individual virulence factor associations have provided conflicting results. Since virulence factors are linked, studies of groups of putative virulence factors are needed to provide clinically useful information. Here, the authors discuss the progress made in understanding the role of H. pylori virulence factors CagA, vacuolating cytotoxin, OipA and DupA in disease pathogenesis and provide suggestions for future studies.

  19. Detection of H pylori antibody profile in serum by protein array

    Institute of Scientific and Technical Information of China (English)

    Feng-Chan Han; Xu-Jun Li; Hong Jiang; Li-Peng Qin; Ding Li; Yan-Hai Guo; Zhi-Guang Liu; Li Zhang; Xiao-Jun Yan

    2006-01-01

    AIM: To detect multiple H pylori antibodies in serum samples of individuals who carryH pyloriby protein array.METHODS: Recombinant H pyloriantigens, urease B subunit (UreB), vacuolating toxin A (VacA) and cytotoxin associated gene A protein (CagA), were prepared and immobilized in matrixes on nitrocellulose membrane by robotics to bind the specific immunoglobulin G (IgG) antibodies in serum. Staphylococcus protein A (SPA) labeled by colloid gold was used to integrate the immuno-complex and gave red color signal, The scanner based on charge-coupled device (CCD) could collect the image signal and convert it into digital signal.RESULTS: When human IgG was printed on the membrane in increasing concentrations and incubated with immunogold, a linear dose response curve was obtained and the detection limit for IgG was about 0.025 ng. The cutoff values, which were defined as the mean grey level plus 3 times of standard deviation, were 27.183, 28.546 and 27.402, for anti-UreB IgG, antiCagA IgG and anti-VacA IgG, respectively, as 400 human serum samples with negative H pylori antibodies were detected by the protein array. When 180 serum samples from patients in hospital were employed for detection of IgG against UreB, CagA and VacA, the sensitivity of the protein array was 93.4%, 95.4%, 96.0%, and the specificity was 94.8%, 94.4% and 97.5%, respectively,as compared with the results obtained by ELISA. The assay also showed high reproducibility, uniformity and stability, and the results were available within 30 min.CONCLUSION: The protein array is a very practical method for rapid detection of multiple antibodies in serum samples. It is especially useful for large scale epidemiological investigation of the infection of Hpylori.

  20. Virulence and potential pathogenicity of coccoid Helicobacter pylori induced by antibiotics

    Science.gov (United States)

    She, Fei-Fei; Su, Dong-Hui; Lin, Jian-Yin; Zhou, Lin-Ying

    2001-01-01

    AIM: To explore the virulence and the potential pathogenicity of coccoid Helicobacter pylori (H. pylori) transformed from spiral form by exposure to antibiotic. METHODS: Three strains of H. pylori, isolated from gastric biopsy specimens of confirmed peptic ulcer, were converted from spiral into coccoid from by exposure to metronidazole. Both spiral and coccoid form of H. pylori were tested for the urease activity, the adherence to Hep 2 cells and the vacuolating cytotoxicity to Hela cells, and the differences of the protein were analysed by SDS-PAGE and Western blot. The mutation of the genes including ureA, ureB, hpaA, vacA and cagA, related with virulence, was detected by means of PCR and PCR-SSCP. RESULTS: In the coccoid H. pylori, the urease activity, the adherence to Hep 2 cells and the vacuolating cytotoxicity to Hela cells alldecreased. In strain F44, the rate and index of adherence reduced from 70.0% ± 5.3% to 33% ± 5.1% and from 2.6 ± 0.4 to 0.96 ± 0.3 (P hpaA or vacA. CONCLUSION: The virulence and the proteins with molecular weight over Mr 74000 in coccoid H.pylori decrease, but no deletion exists in amplification fragments from ureA, ureB, hpaA, vacA and cagA genes, suggesting that coccoid H.pylori may have potential pathogenicity. PMID:11819770

  1. Helicobacter pylori

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    1992-01-01

    Helicobacter pylori (HP) are Gram-negative spiral bacteria which occur in the human stomach. The bacteria were cultured in vitro for the first time in 1983. It is suspected that the bacteria may cause chronic gastritis of type B and may also be a contributory cause of chronic ulceration and cancer...... of the stomach. The bacteria are accompanied by characteristic inflammatory changes in the gastric mucosa. The significance for gastritis, chronic ulceration, non-ulcer dyspepsia and carcinoma of the stomach is discussed. HP occurs in a great proportion of the population of the world and the frequency increases...

  2. Helicobacter pylori

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    1992-01-01

    of the stomach. The bacteria are accompanied by characteristic inflammatory changes in the gastric mucosa. The significance for gastritis, chronic ulceration, non-ulcer dyspepsia and carcinoma of the stomach is discussed. HP occurs in a great proportion of the population of the world and the frequency increases......Helicobacter pylori (HP) are Gram-negative spiral bacteria which occur in the human stomach. The bacteria were cultured in vitro for the first time in 1983. It is suspected that the bacteria may cause chronic gastritis of type B and may also be a contributory cause of chronic ulceration and cancer...

  3. The Clinical Correlations of Helicobacter pylori Virulence Factors and Chronic Spontaneous Urticaria

    Directory of Open Access Journals (Sweden)

    Yi-Chun Chiu

    2013-01-01

    Full Text Available Background and Study Aims. The association between Helicobacter pylori (H. pylori and chronic spontaneous urticaria (CSU remains controversial. This study explored the role of H. pylori in CSU among different virulent genotypes patients. Patients and Methods. Patients infected by H. pylori were sorted into two groups as group A (with CSU and group B (without CSU. The tissue materials were taken via endoscopy for polymerase chain reaction study to determine virulence factors. After H. pylori eradication therapy, the eradication rate and response of urticaria were evaluated by using C13-UBT and a three-point scale (complete remission, partial remission, or no improvement. Results. The results were comparable between patients of groups A and B in terms of H. pylori infection rates and eradication rate. Longitudinal follow-up of 23.5 months showed complete remission of urticaria in 63.6% but no improvement in 36.4% of the patients after H. pylori eradication. H. pylori infected patients with different virulence factors such as cytotoxin-associated gene A, vacuolating cytotoxin gene A signal region and middle region have similar remission rates for CSU. Conclusions. Current study suggests that H. pylori may play a role in the development and disease course of CSU but may be irrelevant to different virulent genotypes.

  4. cag Pathogenicity island-dependent upregulation of matrix metalloproteinase-7 in infected patients with Helicobacter pylori.

    Science.gov (United States)

    Sadeghiani, Marzieh; Bagheri, Nader; Shahi, Heshmat; Reiisi, Somayeh; Rahimian, Ghorbanali; Rashidi, Reza; Mahsa, Majid; Shafigh, Mohammedhadi; Salimi, Elaheh; Rafieian-Kopaei, Mahmoud; Hashemzadeh-Chaleshtori, Morteza; Shirzad, Hedayatollah

    2017-07-12

    Helicobacter pylori (H. pylori) infection has been involved in the pathogenesis of most important gastroduodenal diseases. Matrix metalloproteinases (MMPs) are a large family of zincendopeptidases which play important roles in degradation of extracellular matrix (ECM) and various inflammatory diseases. Therefore, we examined MMP-7 mRNA levels in the gastric mucosa of patients with H. pylori infection and evaluated the effects of virulence factors, such as vacA (vacuolating cytotoxin A) and cagA (cytotoxin-associated gene), in H. pylori-infected patients upon the MMP-7 mRNA mucosal levels. We also determined the correlation between mucosal MMP-7 mRNA levels and the types of disease. Total RNA was extracted from gastric biopsies of 50 H. pylori-infected patients and 50 uninfected individuals. Mucosal MMP-7 mRNA expression level in H. pylori-infected and non-infected gastric biopsies was determined by real-time polymerase chain reaction (PCR). The presences of cagA and vacA virulence factors was evaluated using PCR. MMP-7 expression was significantly higher in biopsies of patients infected with H .pylori compared to uninfected individuals. In addition, mucosal MMP-7 mRNA expression in H. pylori-infected patients significantly associated with the cagA status and the types of disease. Our results suggest that MMP-7 might be involved in the pathogenesis of H. pylori. Peptic ulcer was associated with cag pathogenicity island-dependent MMP-7 upregulation.

  5. CagA and VacA Helicobacter Pylori Antibodies in Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Renzo Suriani

    2008-01-01

    Full Text Available BACKGROUND: Infection with different genotypes of virulent Helicobacter pylori strains (cytotoxin-associated gene A [CagA]-and/or vacuolating cytotoxin A [VacA]-positive can play a role in the development of atrophic gastritis, duodenal ulcer (DU and gastric cancer (GC.

  6. H. pylori Infection

    Science.gov (United States)

    ... think you may have a high risk of stomach cancer, talk to your doctor. Together you can decide whether you may benefit from H. pylori screening. References H. pylori and peptic ulcers. National Institute ...

  7. High prevalence of cytotoxin positive Helicobacter pylori in patients unrelated to the presence of peptic ulcers in Japan

    OpenAIRE

    Ogura, K.; Kanai, F; Maeda, S; Yoshida, H.; Ogura, M; Lan, K; Hirota, K; Kawabe, T; Shiratori, Y.; Omata, M

    1997-01-01

    Background—It has been reported that infection with vacuolating cytotoxin positive Helicobacter pylori strains is associated with gastroduodenal disease in Western countries. 
Aims—To evaluate the prevalence of cytotoxin producing strains among patients with H pylori infection in relation to gastrointestinal diseases in Japan. 
Patients—Ninety seven patients undergoing endoscopy. 
Methods—A Western blot assay was conducted to detect serum antibodies against the cytotoxin usi...

  8. ER and vacuoles: never been closer

    Directory of Open Access Journals (Sweden)

    Corrado eViotti

    2014-02-01

    Full Text Available The endoplasmic reticulum (ER represents the gateway for intracellular trafficking of membrane proteins, soluble cargoes and lipids. In all eukaryotes, the best described mechanism of exiting the ER is via COPII-coated vesicles, which transport both membrane proteins and soluble cargo to the cis-Golgi. The vacuole, together with the plasma membrane, is the most distal point of the secretory pathway, and many vacuolar proteins are transported from the ER through intermediate compartments. However, past results and recent findings demonstrate the presence of alternative transport routes from the ER towards the tonoplast, which are independent of Golgi- and post-Golgi trafficking. Moreover, the transport mechanism of the vacuolar proton pumps VHA-a3 and AVP1 challenges the current model of vacuole biogenesis, pointing to the endoplasmic reticulum for being the main membrane source for the biogenesis of the plant lytic compartment. This review gives an overview of the current knowledge on the transport routes towards the vacuole and discusses the possible mechanism of vacuole biogenesis in plants.

  9. Helicobacter Pylori Infections

    Science.gov (United States)

    Helicobacter pylori (H. pylori) is a type of bacteria that causes infection in the stomach. It is found in about two-thirds of ... or stool to see if it contains H. pylori. The best treatment is a combination of antibiotics ...

  10. Helicobacter pylori and colorectal neoplasia: Is there a causal link?

    Science.gov (United States)

    Papastergiou, Vasilios; Karatapanis, Stylianos; Georgopoulos, Sotirios D

    2016-01-14

    Ever since Helicobacter pylori (H. pylori) was recognized as an infectious cause of gastric cancer, there has been increasing interest in examining its potential role in colorectal carcinogenesis. Data from case-control and cross-sectional studies, mostly relying on hospital-based samples, and several meta-analyses have shown a positive statistical relationship between H. pylori infection and colorectal neoplasia. However, the possibility exists that the results have been influenced by bias, including the improper selection of patients and disparities with respect to potential confounders. While the evidence falls short of a definitive causal link, it appears that infection with H. pylori/H. pylori-related gastritis is associated with an increased, although modest, risk of colorectal adenoma and cancer. The pathogenic mechanisms responsible for this association remain uncertain. H. pylori has been detected in colorectal malignant tissues; however, the possibility that H. pylori is a direct activator of colonic carcinogenesis remains purely hypothetical. On the other hand, experimental data have indicated a series of potential oncogenic interactions between these bacteria and colorectal mucosa, including induction and perpetuation of inflammatory responses, alteration of gut microflora and release of toxins and/or hormonal mediators, such as gastrin, which may contribute to tumor formation.

  11. [The influence of bacterial toxins on the carcinogenesis].

    Science.gov (United States)

    Stachowicz, Anna M; Łaniewski, Paweł; Jagusztyn-Krynicka, Elzbieta K

    2010-01-01

    Bacterial infections may constitute an important risk factor of developing cancer disease. Molecular mechanisms by which bacteria contribute to cancer are extremely complex and still remain not fully understood. So far, it is generally accepted that Helicobacter pylori infections are associated with induction of gastric adenocarcinoma and MALT lymphoma. Two H. pylori toxins which modulate many cellular functions are VacA and CagA. So far, CagA is the only one known bacterial oncoprotein. However, many other bacteria produce toxins or effector proteins perturbing host cell homeostasis or/and evoking chronic inflammation. Both processes may be associated with tumour formation. Bacterial toxins which interfere, with various host signal transduction pathways, deregulate processes of cell division, proliferation and differentiation and modulate apoptosis. Some toxins cause even direct DNA damage. This review discuss the potential links between action of bacterial toxins and cancer.

  12. Recombinant Helicobacter pylori catalase

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Jian-Feng Jin; Ji-De Wang; Zhao-Shan Zhang

    2003-01-01

    AIM: To construct a recombinant strain which highly expresses catalase of Helicobacter pylori(H.pylori) and assay the activity of H. pylori catalase.METHODS: The catalase DNA was amplified from H. pylori chromosomal DNA with PCR techniques and inserted into the prokaryotie expression vector pET-22b (+), and then was transformed into the BL21 (DE3) E. coli strain which expressed catalase recombinant protein. The activity of H.pylori catalase was assayed by the Beers & Sizers.RESULTS: DNA sequence analysis showed that the sequence of catalase DNA was the same as GenBank's research. The catalase recombinant protein amounted to 24.4 % of the total bacterial protein after induced with IPTG for 3 hours at 37 ℃ and the activity of H. pylori catalase was high in the BL21 (DE3) E. coli strain.CONCLUSION: A clone expressing high activity H. pylori catalase is obtained, laying a good foundation for further studies.

  13. Identification of Helicobacter pylori genes that contribute to stomach colonization.

    Science.gov (United States)

    Baldwin, David N; Shepherd, Benjamin; Kraemer, Petra; Hall, Michael K; Sycuro, Laura K; Pinto-Santini, Delia M; Salama, Nina R

    2007-02-01

    Chronic infection of the human stomach by Helicobacter pylori leads to a variety of pathological sequelae, including peptic ulcer and gastric cancer, resulting in significant human morbidity and mortality. Several genes have been implicated in disease related to H. pylori infection, including the vacuolating cytotoxin and the cag pathogenicity island. Other factors important for the establishment and maintenance of infection include urease enzyme production, motility, iron uptake, and stress response. We utilized a C57BL/6 mouse infection model to query a collection of 2,400 transposon mutants in two different bacterial strain backgrounds for H. pylori genetic loci contributing to colonization of the stomach. Microarray-based tracking of transposon mutants allowed us to monitor the behavior of transposon insertions in 758 different gene loci. Of the loci measured, 223 (29%) had a predicted colonization defect. These included previously described H. pylori virulence genes, genes implicated in virulence in other pathogenic bacteria, and 81 hypothetical proteins. We have retested 10 previously uncharacterized candidate colonization gene loci by making independent null alleles and have confirmed their colonization phenotypes by using competition experiments and by determining the dose required for 50% infection. Of the genetic loci retested, 60% have strain-specific colonization defects, while 40% have phenotypes in both strain backgrounds for infection, highlighting the profound effect of H. pylori strain variation on the pathogenic potential of this organism.

  14. Helicobacter pylori in Iran: A systematic review on the association of genotypes and gastroduodenal diseases

    Science.gov (United States)

    Hosseini, Elham; Poursina, Farkhondeh; de Wiele, Tom Van; Safaei, Hajieh Ghasemian; Adibi, Peyman

    2012-01-01

    Background: Helicobacter pylori (H. pylori) infection is known as a major etiologic factor for a variety of gastroduodenal diseases. In Iran, with a high rate of H. pylori infection close to 90%, numerous studies have revealed many aspects of interaction between the bacterium, mucosal surface and induction of disease outcome. The organism is genetically diverse and several virulence factors are attributed to the more virulent strains. The well-characterized virulence factors of H. pylori are cytotoxin associated gene A and vacuolating cytotoxin gene A. The distribution pattern of H. pylori genotypes and its association with disease status varies geographically. The present review focused on the virulence factors and genotyping of H. pylori in relation to gastroduodenal disorders in different regions of Iran. Methods: In total, 398 studies were reported on different aspects related to H. pylori in our electronic search from 1995-2011. H. pylori infection and its virulence factors in association with disease status were investigated in 159 reports. Looking specifically at the gastrointestinal tract disorders, the most relevant reports including 37 papers were selected. Results: We found no correlation of cagA genotype and disease status in the majority of studies, whereas vacA was demonstrated as a useful marker in predicting the disease outcome. The results of reports on other virulence factors of H. pylori such as blood group antigen-binding adhesion gene A, the induced by contact with epithelium gene A, the outer inflammatory protein A, the duodenal ulcer promoting gene A, and Helicobacter outer membrane gene and their relation with disease status were contradictory. Conclusions: Although different markers of H. pylori were emphasized as useful when predicting disease outcomes in some studies, the inconsistent researches and the scarcity of data made any conclusion or even comparison impossible. Considering the gap of information observed during our search

  15. H1-antihistamines induce vacuolation in astrocytes through macroautophagy

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Wei-Wei; Yang, Ying; Wang, Zhe; Shen, Zhe; Zhang, Xiang-Nan [Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, School of Basic Medical Sciences, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058 (China); Wang, Guang-Hui [College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123 (China); Chen, Zhong, E-mail: chenzhong@zju.edu.cn [Department of Pharmacology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, School of Basic Medical Sciences, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058 (China)

    2012-04-15

    H1-antihistamines induce vacuolation in vascular smooth muscle cells, which may contribute to their cardiovascular toxicity. The CNS toxicity of H1-antihistamines may also be related to their non-receptor-mediated activity. The aim of this study was to investigate whether H1-antihistamines induce vacuolation in astrocytes and the mechanism involved. The H1-antihistamines induced large numbers of giant vacuoles in astrocytes. Such vacuoles were marked with both the lysosome marker Lysotracker Red and the alkalescent fluorescence dye monodansylcadaverine, which indicated that these vacuoles were lysosome-like acidic vesicles. Quantitative analysis of monodansylcadaverine fluorescence showed that the effect of H1-antihistamines on vacuolation in astrocytes was dose-dependent, and was alleviated by extracellular acidification, but aggravated by extracellular alkalization. The order of potency to induce vacuolation at high concentrations of H1-antihistamines (diphenhydramine > pyrilamine > astemizole > triprolidine) corresponded to their pKa ranking. Co-treatment with histamine and the histamine receptor-1 agonist trifluoromethyl toluidide did not inhibit the vacuolation. Bafilomycin A1, a vacuolar (V)-ATPase inhibitor, which inhibits intracellular vacuole or vesicle acidification, clearly reversed the vacuolation and intracellular accumulation of diphenhydramine. The macroautophagy inhibitor 3-methyladenine largely reversed the percentage of LC3-positive astrocytes induced by diphenhydramine, while only partly reversing the number of monodansylcadaverine-labeled vesicles. In Atg5{sup −/−} mouse embryonic fibroblasts, which cannot form autophagosomes, the number of vacuoles induced by diphenhydramine was less than that in wild-type cells. These results indicated that H1-antihistamines induce V-ATPase-dependent acidic vacuole formation in astrocytes, and this is partly mediated by macroautophagy. The pKa and alkalescent characteristic of H1-antihistamines may be the

  16. Genipin-cross-linked fucose-chitosan/heparin nanoparticles for the eradication of Helicobacter pylori.

    Science.gov (United States)

    Lin, Yu-Hsin; Tsai, Shih-Chang; Lai, Chih-Ho; Lee, Che-Hsin; He, Zih Sian; Tseng, Guan-Chin

    2013-06-01

    Helicobacter pylori is a significant human pathogen that recognizes specific carbohydrate receptors, such as the fucose receptor, and produces the vacuolating cytotoxin, which induces inflammatory responses and modulates the cell-cell junction integrity of the gastric epithelium. The clinical applicability of topical antimicrobial agents was needed to complete the eradication of H. pylori in the infected fundal area. In the present study, we combined fucose-conjugated chitosan and genipin-cross-linking technologies in preparing multifunctional genipin-cross-linked fucose-chitosan/heparin nanoparticles to encapsulate amoxicillin of targeting and directly make contact with the region of microorganism on the gastric epithelium. The results show that the nanoparticles effectively reduced drug release at gastric acids and then released amoxicillin in an H. pylori survival situation to inhibit H. pylori growth and reduce disruption of the cell-cell junction protein in areas of H. pylori infection. Furthermore, with amoxicillin-loaded nanoparticles, a more complete H. pylori clearance effect was observed, and H. pylori-associated gastric inflammation in an infected animal model was effectively reduced.

  17. Frequency of virulence factors in Helicobacter pylori-infected patients with gastritis.

    Science.gov (United States)

    Salimzadeh, Loghman; Bagheri, Nader; Zamanzad, Behnam; Azadegan-Dehkordi, Fatemeh; Rahimian, Ghorbanali; Hashemzadeh-Chaleshtori, Morteza; Rafieian-Kopaei, Mahmoud; Sanei, Mohammad Hossein; Shirzad, Hedayatollah

    2015-03-01

    The outcome of Helicobacter pylori infection has been related to specific virulence-associated bacterial genotypes. The vacuolating cytotoxin (vacA), cagA gene, oipA and babA2 gene are important virulence factor involving gastric diseases. The objective of this study was to assess the relationship between virulence factors of H. pylori and histopathological findings. Gastroduodenoscopy was performed in 436 dyspeptic patients. Antrum biopsy was obtained for detection of H. pylori, virulence factors and for histopathological assessment. The polymerase chain reaction was used to detect virulence factors of H. pylori using specific primers. vacA genotypes in patients infected with H. pylori were associated with cagA, iceA1 and iceA2. In the patients with H. pylori infection there was a significant relationship between cagA positivity and neutrophil activity (P = 0.004) and chronic inflammation (P = 0.013) and with H. pylori density (P = 0.034). Neutrophil infiltration was found to be more severe in the s1 group than in the s2 group (P = 0.042). Also was a significant relationship between oipA positivity and neutrophil activity (P = 0.004) and with H. pylori density (P = 0.018). No significant relationships were observed between other vacA genotypes and histopathological parameters. H. pylori strains showing cagA, vacA s1 and oipA positivity are associated with more severe gastritis in some histological features but virulence factors of H. pylori do not appear to determine the overall pattern of gastritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Treatment of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Adam Harris

    2001-01-01

    @@ INTRODUCTION Using an evidence-based approach this review discusses the current treatment of Helicobacter pylori infection in patients with peptic ulcer disease, functional (non-ulcer)dyspepsia or gastro-oesophageal reflux disease (GORD).It also briefly addresses the potential role of eradication of H . pylori in preventing gastric cancer .

  19. Vacuolation induced by unfavorable pH in cyanobacteria

    Institute of Scientific and Technical Information of China (English)

    赵以军; 吴红艳; 郭厚良; 许敏; 程凯; 祝海燕

    2001-01-01

    Six species or strains of cyanobacteria, Anabaena sp. 595, Plectonema boryanum 246, Scytonema hofmanni 248, Nostoc sp. 96, Oscillatoria animlis 284 and Spirulina maxima 438, were cultured in unfavorable pH conditions for vacuole induction. At pH 5.0, 6.5, or 7.0, vacuoles were observed to form in both Anabaena sp. 595 and Plectonema boryanum 246, especially in the former. The vacuolation took place with some morphological changes, such as the cells being inflated, spherical and vacuolated, and with unequalized division. The induced vacuoles in An- abaena sp. 595 and Plectonema boryanum 246 were in spherical shape and in rather transparent appearance under a phase microscope. For Scytonema hofmanni 248, it was less sensitive to pH, its vacuole formation was found only at pH 6.5. No vacuolization occurred in the cells of Nostoc sp. 96, Oscillatoria animlis 284 and Spirulina maxima 438 at all pH conditions we used. Vacuolization under unfavorable pH provides a new proof for the existence of vacuole in cells of cyanobacteria and reflects the prokaryote's function in ecological environment.

  20. Differences in Genotypes of Helicobacter pylori from Different Human Populations

    Science.gov (United States)

    Kersulyte, Dangeruta; Mukhopadhyay, Asish K.; Velapatiño, Billie; Su, WanWen; Pan, ZhiJun; Garcia, Claudia; Hernandez, Virginia; Valdez, Yanet; Mistry, Rajesh S.; Gilman, Robert H.; Yuan, Yuan; Gao, Hua; Alarcón, Teresa; López-Brea, Manuel; Balakrish Nair, G.; Chowdhury, Abhijit; Datta, Simanti; Shirai, Mutsunori; Nakazawa, Teruko; Ally, Reidwaan; Segal, Isidore; Wong, Benjamin C. Y.; Lam, S. K.; Olfat, Farzad O.; Borén, Thomas; Engstrand, Lars; Torres, Olga; Schneider, Roberto; Thomas, Julian E.; Czinn, Steven; Berg, Douglas E.

    2000-01-01

    DNA motifs at several informative loci in more than 500 strains of Helicobacter pylori from five continents were studied by PCR and sequencing to gain insights into the evolution of this gastric pathogen. Five types of deletion, insertion, and substitution motifs were found at the right end of the H. pylori cag pathogenicity island. Of the three most common motifs, type I predominated in Spaniards, native Peruvians, and Guatemalan Ladinos (mixed Amerindian-European ancestry) and also in native Africans and U.S. residents; type II predominated among Japanese and Chinese; and type III predominated in Indians from Calcutta. Sequences in the cagA gene and in vacAm1 type alleles of the vacuolating cytotoxin gene (vacA) of strains from native Peruvians were also more like those from Spaniards than those from Asians. These indications of relatedness of Latin American and Spanish strains, despite the closer genetic relatedness of Amerindian and Asian people themselves, lead us to suggest that H. pylori may have been brought to the New World by European conquerors and colonists about 500 years ago. This thinking, in turn, suggests that H. pylori infection might have become widespread in people quite recently in human evolution. PMID:10809702

  1. Polyamine toxins

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Jensen, Lars S; Vogensen, Stine B

    2005-01-01

    Polyamine toxins, isolated from spiders and wasps, have been used as pharmacological tools for the study of ionotropic receptors, but their use have so far been hampered by their lack of selectivity. In this mini-review, we describe how careful synthetic modification of native polyamine toxins have...

  2. Pertussis toxin

    Energy Technology Data Exchange (ETDEWEB)

    Sekura, R.D.; Moss, J.; Vaughan, M.

    1985-01-01

    This book contains 13 selections. Some of the titles are: Genetic and Functional Studies of Pertussis Toxin Substrates; Effect of Pertussis Toxin on the Hormonal Responsiveness of Different Tissues; Extracellular Adenylate Cyclase of Bordetella pertussis; and GTP-Regulatory Proteins are Introcellular Messagers: A Model for Hormone Action.

  3. Evaluating the validity of the serologic test for detecting Helicobacter pylori infection in Mongolian gerbils.

    Science.gov (United States)

    Kuo, Chao-Hung; Yu, Fang-Jung; Tsai, Pei-Yun; Yang, Sheau-Fang; Chang, Lin-Li; Jan, Chang-Ming; Wang, Wen-Ming; Wu, Deng-Chyang

    2007-11-01

    A strong correlation between Helicobacter pylori infection and gastric cancer has been reported. Mongolian gerbils are regarded as the most suitable animal model in which to study carcinogenesis associated with H. pylori. The aim of our study was to evaluate the accuracy of the serologic test for detecting H. pylori infection in Mongolian gerbils. The model was developed as follows: the H. pylori colony (vacuolating cytotoxin A (+)/cytotoxin-associated gene A (+)) was cultured from the mucosas of previously H. pylori-fed gerbils. These colonies were cultured in broth. Then,we fed the gerbils with 0.5-1 mL of broth (about 10(9) CFU/mL) (intragastric administration) twice within a 3-day period. After inoculation for 6 or 26 weeks, the gerbils were sacrificed and their gastric mucosas were sampled for a series of examinations. Blood samples for serologic testing (STAT-PAK) were collected. H. pylori infection was confirmed. Statistical analysis was performed using the Chi-square test. Differences were regarded as significant when the p value was less than 0.05. A total of 50 gerbils were inoculated with H. pylori and the success rate reached 88%. All 10 gerbils in the control group showed a negative result. Damage to the mucosas was more obvious following increasing periods of inoculation. The rates of sensitivity and specificity, as determined by the STAT-PAK test, were 90.9% and 100%, respectively. The positive and negative predictive values were 100% and 60%, respectively. The STAT-PAK test seemed to be more sensitive and accurate (p < 0.05) in high H. pylori densities. In conclusion, the STAT-PAK test (blood-sampling) showed acceptable results and was suitable for long-term observation of H. pylori infection.

  4. Mixed Infections of Helicobacter pylori Isolated from Patients with Gastrointestinal Diseases in Taiwan

    Directory of Open Access Journals (Sweden)

    Chih-Ho Lai

    2016-01-01

    Full Text Available Background. Persistent Helicobacter pylori infection may induce several upper gastrointestinal diseases. Two major virulence factors of H. pylori, vacuolating cytotoxin A (VacA and cytotoxin-associated gene A (CagA, are thought to be associated with the severity of disease progression. The distribution of vacA and cag-pathogenicity island (cag-PAI alleles varies in H. pylori isolated from patients in different geographic regions. Aim. To assess the association between mixed infection of H. pylori clinical isolates from Taiwanese patients and the severity of gastrointestinal diseases. Methods. A total of 70 patients were enrolled in this study. Six distinct and well-separated colonies were isolated from each patient and 420 colonies were analyzed to determine the genotypes of virulence genes. Results. The prevalence of mixed infections of all H. pylori-infected patients was 28.6% (20/70. The rate of mixed infections in patients with duodenal ulcer (47.6% was much higher than that with other gastrointestinal diseases (P<0.05. Conclusions. H. pylori mixed infections show high genetic diversity that may enhance bacterial adaptation to the hostile environment of the stomach and contribute to disease development.

  5. Mixed Infections of Helicobacter pylori Isolated from Patients with Gastrointestinal Diseases in Taiwan

    Science.gov (United States)

    Huang, Ju-Chun; Chiang-Ni, Chuan; Li, Ju-Pi; Wu, Lii-Tzu; Wu, Hua-Shan; Sun, Yu-Chen; Lin, Mei-Ling; Lee, Ju-Fang

    2016-01-01

    Background. Persistent Helicobacter pylori infection may induce several upper gastrointestinal diseases. Two major virulence factors of H. pylori, vacuolating cytotoxin A (VacA) and cytotoxin-associated gene A (CagA), are thought to be associated with the severity of disease progression. The distribution of vacA and cag-pathogenicity island (cag-PAI) alleles varies in H. pylori isolated from patients in different geographic regions. Aim. To assess the association between mixed infection of H. pylori clinical isolates from Taiwanese patients and the severity of gastrointestinal diseases. Methods. A total of 70 patients were enrolled in this study. Six distinct and well-separated colonies were isolated from each patient and 420 colonies were analyzed to determine the genotypes of virulence genes. Results. The prevalence of mixed infections of all H. pylori-infected patients was 28.6% (20/70). The rate of mixed infections in patients with duodenal ulcer (47.6%) was much higher than that with other gastrointestinal diseases (P < 0.05). Conclusions. H. pylori mixed infections show high genetic diversity that may enhance bacterial adaptation to the hostile environment of the stomach and contribute to disease development. PMID:27738429

  6. Clinical significance of infection with cag A and vac A positive helicobacter pylori strains

    Directory of Open Access Journals (Sweden)

    Sokić-Milutinović Aleksandra

    2004-01-01

    Full Text Available Clinical relevance of infection with different Helicobacter pylori strains was reviewed in this paper. Helicobacter pylori (H. pylori infection plays a role in pathogenesis of chronic gastritis, peptic ulcer disease, gastric adenocarcinoma and MALT lymphoma. Extragastric manifestations of H. pylori infection most probably include acne rosacea and chronic urticaria, while the importance of H. pylori infection for pathogenesis of growth retardation in children, iron deficiency anemia, coronary heart disease, stroke and idiopathic thrombocytopenic purpura remains vague. The expression of two H. pylori proteins, cytotoxin associated protein (cag A and vacuolization cytotoxin (vac A is considered to be related with pathogenicity of the bacterium. It is clear that presence of cag A+ strains is important for development of peptic ulcer; nevertheless, it is also protective against esophageal reflux disease. On the other hand, cag A+ strains are common in gastric adenocarcinoma and MALT lymphoma patients, but it seems that certain subtypes of vac A cytotoxin are more important risk factors. Infection with cag A+ strains is more common in patients with acne rosacea, stroke and coronary heart disease.

  7. Helicobacter pylori in pediatrics.

    Science.gov (United States)

    Homan, Matjaž; Hojsak, Iva; Kolaček, Sanja

    2012-09-01

    This review summarizes important pediatric studies published from April 2011 up to March 2012. Proteomics profile of ulcerogenic Helicobacter pylori strains was defined in the most interesting study of the last year. The antigen stool test is becoming the "gold standard" in prevalence studies, and according to the last epidemiologic studies, the prevalence of H. pylori infection in childhood is not decreasing any more in the developed world. The resistance rate of H. pylori strains is high in children. Therefore, among other important issues concerning H. pylori in pediatrics, guidelines published by ESPGHAN and NASPGHAN last year also recommended culture and susceptibility testing before first-line treatment in areas with high or unknown antibiotic resistance rates.

  8. Pseudomembranous colitis associated with a triple therapy for Helicobacter pylori eradication.

    Science.gov (United States)

    Trifan, Anca; Girleanu, Irina; Cojocariu, Camelia; Sfarti, Catalin; Singeap, Ana Maria; Dorobat, Carmen; Grigore, Lucia; Stanciu, Carol

    2013-11-14

    Helicobacter pylori (H. pylori) is one of the most common chronic bacterial infections in humans, affecting half of world's population. Therapy for H. pylori infection has proven to be both effective and safe. The one-week triple therapy including proton pump inhibitor, clarithromycin, and amoxicillin or metronidazole is still recommended as a first-line treatment to eradicate H. pylori infection in countries with low clarithromycin resistance. Generally, this therapy is well-tolerated, with only a few and usually minor side effects. However, rare but severe adverse effects such as pseudomembranous colitis have been reported, Clostridium difficile (C. difficile) infection being the main causative factor in all cases. We report the cases of two women who developed pseudomembranous colitis after a 1-wk triple therapy consisting of pantoprazole 20 mg bid, clarithromycin 500 mg bid, and amoxicillin 1 g bid to eradicate H. pylori infection. A limited colonoscopy showed typical appearance of pseudomembranous colitis, and the stool test for C. difficile toxins was positive. Rapid resolution of symptoms and negative C. difficile toxins were obtained in both patients with oral vancomycin. No relapse occurred during a four and eleven-month, respectively, follow up. These cases suggest that physicians should have a high index of suspicion for pseudomembranous colitis when evaluate patients with diarrhea following H. pylori eradication therapy.

  9. Immunity and Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Paul Harris

    2011-03-01

    Full Text Available The bacteria called Helicobacter pylori arrived to the American continent 12,000 years ago (1, reaching South America roughly 5,400-4,600 years AC according to research by Pelayo Correa, a Colombian pathologist who found Helicobacter in stool next to Chinchorro mummies in the North of Arica close to the Pacific Ocean. In 2005, Barry Marshall was awarded the Nobel Prize for his studies on Helicobacter pylori together with Robin Warren.

  10. Helicobacter pylori and nonmalignant diseases.

    LENUS (Irish Health Repository)

    Alakkari, Alaa

    2012-02-01

    Research published over the past year has documented the continued decline of Helicobacter pylori-related peptic ulcer disease and increased recognition of non-H. pylori, non-steroidal anti-inflammatory drugs ulcer disease--idiopathic ulcers. Despite reduced prevalence of uncomplicated PUD, rates of ulcer complications and associated mortality remain stubbornly high. The role of H. pylori in functional dyspepsia is unclear, with some authors considering H. pylori-associated nonulcer dyspepsia a distinct organic entity. There is increasing acceptance of an inverse relationship between H. pylori and gastroesophageal reflux disease (GERD), but little understanding of how GERD might be more common\\/severe in H. pylori-negative subjects. Research has focused on factors such as different H. pylori phenotypes, weight gain after H. pylori eradication, and effects on hormones such as ghrelin that control appetite.

  11. Sensitivity of Hep G2 cells to Bacillus cereus emetic toxin.

    Science.gov (United States)

    Kamata, Yoichi; Kanno, Shinji; Mizutani, Noriko; Agata, Norio; Kawakami, Hiroshi; Sugiyama, Kei-ichi; Sugita-Konishi, Yoshiko

    2012-11-01

    We herein examined the sensitivity of Hep G2 human hepatoma cells to Bacillus cereus emetic toxin. Hep G2 cells were treated with the emetic toxin, and the cell shape was observed. The same experiments were performed for comparison purposes, using HEp-2 cells, which are currently used by most laboratories for a bioassay of the emetic toxin. Hep G2 cells showed clearer vacuolation in the cytosol within 2 hr and required a shorter incubation period than HEp-2 cells (10 hr). The number of vacuoles in the Hep G2 cells was greater, and the size of the vacuoles was larger than those observed in HEp-2 cells. The minimal concentration of the emetic toxin required to induce the vacuolation of Hep G2 cells was 0.04 ng/ml. The concentration for the HEp-2 cells was 1 ng/ml. These findings indicate that Hep G2 cells show higher sensitivity to the emetic toxin. Hep G2 cells may be superior to the currently used HEp-2 cells for the bioassay of the emetic toxin.

  12. V-ATPase, ScNhxlp and Yeast Vacuole Fusion

    Institute of Scientific and Technical Information of China (English)

    Quan-Sheng Qiu

    2012-01-01

    Membrane fusion is the last step in trafficking pathways during which membrane vesicles fuse with target organelles to deliver cargos.It is a central cellular reaction that plays important roles in signal transduction,protein sorting and subcellular compartmentation.Recent progress in understanding the roles of ion transporters in vacuole fusion in yeast is summanzed in this article.It is becoming increasingly evident that the vacuolar proton pump V-ATPase and vacuolar Na+/H+ antiporter ScNhxlp are key components of the vacuole fusion machinery in yeast.Yeast ScNhxlp regulates vacuole fusion by controlling the luminal pH.V-ATPases serve a dual role in vacuolar integrity in which they regulate both vacuole fusion and fission reactions in yeast.Fission defects are epistatic to fusion defects.Vacuole fission depends on the proton translocation activity of the V-ATPase; by contrast,the fusion reaction does not need the transport activity but requires the physical presence of the proton pump.Vo,the membrane-integral sector of the V-ATPase,forms trans-complexes between the opposing vacuoles in the terminal phase of vacuole fusion where the Vo trans-complexes build a continuous proteolipid channel at the fusion site to mediate the bilayer fusion.

  13. Detection of cytoplasmic proteins from Helicobacter pylori in Colony Lift Immunoassay.

    Science.gov (United States)

    Rojas-Rengifo, Diana F; Jaramillo, Carlos A; Haas, Rainer; Jiménez-Soto, Luisa F

    2015-12-01

    Use of the Colony Lift Immunoassay has been described for several Gram negative bacteria of medical interest. In all cases detection was limited to the use of antibodies against outer membrane proteins. Here we describe the adaptation of this method for detection of the cytoplasmic CagA toxin from Helicobacter pylori.

  14. Halitosis and Helicobacter pylori infection

    NARCIS (Netherlands)

    Tangerman, A.; Winkel, E. G.; de Laat, L.; van Oijen, A. H.; de Boer, W. A.

    2012-01-01

    There is disagreement about a possible relationship between Helicobacter pylori (H. pylori) infection and objective halitosis, as established by volatile sulfur compounds (VSCs) in the breath. Many studies related to H. pylori used self-reported halitosis, a subjective and unreliable method to detec

  15. Halitosis and Helicobacter pylori infection

    NARCIS (Netherlands)

    Tangerman, A.; Winkel, E. G.; de Laat, L.; van Oijen, A. H.; de Boer, W. A.

    There is disagreement about a possible relationship between Helicobacter pylori (H. pylori) infection and objective halitosis, as established by volatile sulfur compounds (VSCs) in the breath. Many studies related to H. pylori used self-reported halitosis, a subjective and unreliable method to

  16. Type IV secretion system in Helicobacter pylori: a new insight into pathogenicity

    Institute of Scientific and Technical Information of China (English)

    ZHONG Qiao; SHAO Shi-he; CUI Lei-lei; MU Run-hong; JU Xiao-li; DONG Su-rong

    2007-01-01

    Objective To review the research progress on Type IV secretion system (T4SS) in Helicobacter pylori.Data sources The data used in this review were identified by searching of PUBMED (1995-2007) online resources Study selection Mainly original articles and critical reviews written by major pioneer investigators of this field were selected.Results The research progress on T4SS in Helicobacter pylori was summarized.The structure and function was discussed.Conclusions T4SS is not only involved in toxin secretion and injection of virulence factors into eukaryotic host target cells,but also involved in horizontal DNA transfer to other bacteria and eukaryotic cells,through DNA uptake from or release into the extracellular milieu.It provides a new insight into the pathogenicity of Helicobacter pylori and a novel target for antimicrobials development.However,many challenges remain for us in understanding the biological role of T4SS in Helicobacter pylori.

  17. Botulinum toxin

    Directory of Open Access Journals (Sweden)

    Nigam P

    2010-01-01

    Full Text Available Botulinum toxin, one of the most poisonous biological substances known, is a neurotoxin produced by the bacterium Clostridium botulinum. C. botulinum elaborates eight antigenically distinguishable exotoxins (A, B, C 1 , C 2 , D, E, F and G. All serotypes interfere with neural transmission by blocking the release of acetylcholine, the principal neurotransmitter at the neuromuscular junction, causing muscle paralysis. The weakness induced by injection with botulinum toxin A usually lasts about three months. Botulinum toxins now play a very significant role in the management of a wide variety of medical conditions, especially strabismus and focal dystonias, hemifacial spasm, and various spastic movement disorders, headaches, hypersalivation, hyperhidrosis, and some chronic conditions that respond only partially to medical treatment. The list of possible new indications is rapidly expanding. The cosmetological applications include correction of lines, creases and wrinkling all over the face, chin, neck, and chest to dermatological applications such as hyperhidrosis. Injections with botulinum toxin are generally well tolerated and side effects are few. A precise knowledge and understanding of the functional anatomy of the mimetic muscles is absolutely necessary to correctly use botulinum toxins in clinical practice.

  18. Identification and characterization of receptors for vacuolating activity of subtilase cytotoxin.

    Science.gov (United States)

    Yahiro, Kinnosuke; Morinaga, Naoko; Satoh, Mamoru; Matsuura, Gen; Tomonaga, Takeshi; Nomura, Fumio; Moss, Joel; Noda, Masatoshi

    2006-10-01

    Some shiga toxin-producing Escherichia coli secrete a novel AB5 cytotoxin, named subtilase cytotoxin (SubAB), which induces vacuole formation in addition to cytotoxicity in susceptible cells. By immunoprecipitation with SubAB from Vero cells, we discovered proteins of 100 kDa, 135 kDa and 155 kDa as potential candidates for its receptor. These proteins were N-glycosylated in their extracellular domains, a modification that was necessary for interaction with SubAB. Biotinylated receptors were partially purified by Datura stramonium agglutinin affinity chromatography and avidin-agarose and analysed by TOF mass spectroscopy. The peptide sequences of p135 were identical to beta1 integrin, and its identification was confirmed with anti-integrin beta1 antibody. The p155 protein was identified as alpha2 integrin using anti-integrin alpha2 antibody. In addition, treatment of Vero cells with beta1 integrin RNAi before exposure to SubAB prevented vacuolating activity. These results suggested that SubAB recognizes alpha2beta1 integrin as a functional receptor; this first interaction may be an important key step leading to the SubAB-induced morphological changes in Vero cells.

  19. Virulence and potential pathogenicity of coccoid Helicobacter pylori induced by antibiotics

    Institute of Scientific and Technical Information of China (English)

    Fei Fei She; Dong Hui Su; Jian Yin Lin; Lin Ying Zhou

    2001-01-01

    AIM To explore the virulence and the potential pathogenicity of coccoid Helicobacter pylori (H. pylori) transformed from spiral form by exposure to antibiotic.METHODS Three strains of H. pylori, isolated from gastric biopsy specimens of confirmed peptic ulcer, were converted from spiral into coccoid from by exposure to metronidazole.Both spiral and coccoid form of H. pylori were tested for the urease activity, the adherence to Hep-2 cells and the vacuolating cytotoxicity to Hela cells, and the differences of the protein were analysed by SDS-PAGE and Western blot,The mutation of the genes including ureA, ureB,hpaA; vacA and cagA, related with virulence,was detected by means of PCR and PCR-SSCP.RESULTS In the coccoid H. pylori, the urease activity, the adherence to Hep-2 cells and the vacuolating cytotoxicity to Hela cells alldecreased. In strain F44, the rate and index of adherence reduced from 70.0% ± 5.3% to 33% ±5.1% and from 2.6 ±0.4 to 0.96 ±0.3 (P<0.01),respectively. The invasion of coccoid H. pylori into Hep-2 cell could be seen under electronmicroscope. SDS-PAGE showed that the content of the protein with the molecular weight over Mr74 000 decreased, and the hybriditional signal in band Mr 125 000 weakened, while the band Mr 110000 and Mr63000 strengthened in coccoid H. pylori as shown in Western blot. The results of PCR were all positive, and PCR-SSCP indicated that there may exist the point mutation in gene hpaA or vacA.CONCLUSION The virulence and the proteins with molecular weight over Mr74 000 in coccoid H. pylori decrease, but no deletion exists in amplification fragments from ureA, ureB, hpaA,vacA and cagA genes, suggesting that coccoid H. pylori may have potential pathogenicity.

  20. Identification of Genes Affecting Vacuole Membrane Fragmentation in Saccharomyces cerevisiae

    Science.gov (United States)

    Michaillat, Lydie; Mayer, Andreas

    2013-01-01

    The equilibrium of membrane fusion and fission influences the volume and copy number of organelles. Fusion of yeast vacuoles has been well characterized but their fission and the mechanisms determining vacuole size and abundance remain poorly understood. We therefore attempted to systematically characterize factors necessary for vacuole fission. Here, we present results of an in vivo screening for deficiencies in vacuolar fragmentation activity of an ordered collection deletion mutants, representing 4881 non-essential genes of the yeast Saccharomyces cerevisiae. The screen identified 133 mutants with strong defects in vacuole fragmentation. These comprise numerous known fragmentation factors, such as the Fab1p complex, Tor1p, Sit4p and the V-ATPase, thus validating the approach. The screen identified many novel factors promoting vacuole fragmentation. Among those are 22 open reading frames of unknown function and three conspicuous clusters of proteins with known function. The clusters concern the ESCRT machinery, adaptins, and lipases, which influence the production of diacylglycerol and phosphatidic acid. A common feature of these factors of known function is their capacity to change membrane curvature, suggesting that they might promote vacuole fragmentation via this property. PMID:23383298

  1. Consequences of Helicobacter pylori infection in children

    OpenAIRE

    Pacifico, Lucia; Anania, Caterina; Osborn, John F.; Ferraro, Flavia; Chiesa, Claudio

    2010-01-01

    Although evidence is emerging that the prevalence of Helicobacter pylori (H. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. If untreated, H. pylori infection is lifelong. Although H. pylori typically colonizes the human stomach for many decades without adverse consequences, children infected with H. pylori can manifest gastrointestinal diseases. Controversy persists regarding testing (and treating) for H. pylori infection in children wit...

  2. Consequences of Helicobacter pylori infection in children

    Institute of Scientific and Technical Information of China (English)

    Lucia; Pacifico; Caterina; Anania; John; F; Osborn; Flavia; Ferraro; Claudio; Chiesa

    2010-01-01

    Although evidence is emerging that the prevalence of Helicobacter pylori (H. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. If untreated, H. pylori infection is lifelong. Although H. pylori typically colonizes the hu-man stomach for many decades without adverse con-sequences, children infected with H. pylori can manifest gastrointestinal diseases. Controversy persists regarding testing (and treating) for H. pylori infection in children with recurrent a...

  3. Helicobacter pylori vacA Genotypes in Chronic Gastritis and Gastric Carcinoma Patients from Macau, China

    Directory of Open Access Journals (Sweden)

    Ines Pinto-Ribeiro

    2016-05-01

    Full Text Available Helicobacter pylori is the major triggering factor for gastric carcinoma, but only a small proportion of infected patients develop this disease. Differences in virulence observed among H. pylori strains, namely in the vacuolating cytotoxin vacA gene, may contribute to this discrepancy. Infection with vacA s1, i1 and m1 strains increases the risk for progression of gastric premalignant lesions and for gastric carcinoma. However, in East Asian countries most of the H. pylori strains are vacA s1, regardless of the patients’ clinical status, and the significance of the vacA i1 and m1 genotypes for gastric carcinoma in this geographic area remains to be fully elucidated. The aim of the present study was to investigate this relationship in 290 patients from Macau, China. Using very sensitive and accurate genotyping methods, we detected infection with vacA i1 and with vacA m1 strains in, respectively, 85.2% and 52.6% of the patients that were infected with single genotypes. The prevalence of cagA-positive strains was 87.5%. No significant associations were observed between vacA genotypes or cagA and gastric carcinoma. It is worth noting that 37.5% of the infected patients had coexistence of H. pylori strains with different vacA genotypes. Additional studies directed to other H. pylori virulence factors should be performed to identify high risk patients in East Asia.

  4. Helicobacter pylori Disrupts Host Cell Membranes, Initiating a Repair Response and Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Hsueh-Fen Juan

    2012-08-01

    Full Text Available Helicobacter pylori (H. pylori, the human stomach pathogen, lives on the inner surface of the stomach and causes chronic gastritis, peptic ulcer, and gastric cancer. Plasma membrane repair response is a matter of life and death for human cells against physical and biological damage. We here test the hypothesis that H. pylori also causes plasma membrane disruption injury, and that not only a membrane repair response but also a cell proliferation response are thereby activated. Vacuolating cytotoxin A (VacA and cytotoxin-associated gene A (CagA have been considered to be major H. pylori virulence factors. Gastric cancer cells were infected with H. pylori wild type (vacA+/cagA+, single mutant (ΔvacA or ΔcagA or double mutant (ΔvacA/ΔcagA strains and plasma membrane disruption events and consequent activation of membrane repair components monitored. H. pylori disrupts the host cell plasma membrane, allowing localized dye and extracellular Ca2+ influx. Ca2+-triggered members of the annexin family, A1 and A4, translocate, in response to injury, to the plasma membrane, and cell surface expression of an exocytotic maker of repair, LAMP-2, increases. Additional forms of plasma membrane disruption, unrelated to H. pylori exposure, also promote host cell proliferation. We propose that H. pylori activation of a plasma membrane repair is pro-proliferative. This study might therefore provide new insight into potential mechanisms of H. pylori-induced gastric carcinogenesis.

  5. Helicobacter pylori Infection in Pediatrics.

    Science.gov (United States)

    Roma, Eleftheria; Miele, Erasmo

    2015-09-01

    This review includes the main pediatric studies published from April 2014 to March 2015. The host response of Treg cells with increases in FOXP3 and TGF-β1 combined with a reduction in IFN-γ by Teff cells may contribute to Helicobacter pylori susceptibility in children. Genotypic variability in H. pylori strains influences the clinical manifestation of the infection. Helicobacter pylori infection is associated with variables indicative of a crowded environment and poor living conditions, while breast-feeding has a protective effect. Intrafamilial infection, especially from mother to children and from sibling to sibling, is the dominant transmission route. Studies showed conflicting results regarding the association between H. pylori infection and iron deficiency anemia. One study suggests that H. pylori eradication plays a role in the management of chronic immune thrombocytopenic purpura in H. pylori-infected children and adolescents. The prevalence of H. pylori was higher in chronic urticaria patients than in controls and, following H. pylori eradication, urticarial symptoms disappeared. An inverse relationship between H. pylori infection and allergic disease was reported. Antibiotic resistance and insufficient compliance to treatment limit the efficacy of eradication therapy. Sequential therapy had no advantage over standard triple therapy. In countries where H. pylori infection is prevalent, studies focusing on virulence factors and antibiotic susceptibility may provide anticipation of the prognosis and may be helpful to reduce morbidity and mortality.

  6. The vacuolar V1/V0-ATPase is involved in the release of the HOPS subunit Vps41 from vacuoles, vacuole fragmentation and fusion

    DEFF Research Database (Denmark)

    Takeda, Kozue; Cabrera, Margarita; Rohde, Jan

    2008-01-01

    At yeast vacuoles, phosphorylation of the HOPS subunit Vps41 depends on the Yck3 kinase. In a screen for mutants that mimic the yck3Delta phenotype, in which Vps41 accumulates in vacuolar dots, we observed that mutants in the V0-part of the V0/V1-ATPase, in particular in vma16Delta, also accumulate...... Vps41. This accumulation is not due to a phosphorylation defect, but to reduced release of Vps41 from vma16Delta vacuoles. One reason could be a connection to vacuole fission, which is blocked in V-ATPase mutants. Vacuole fusion is not impaired between vacuoles lacking the V0-subunits Vma16 or Vma6...... and wild-type vacuoles, whereas fusion between mutant vacuoles is reduced. Our data suggest a connection between vacuole biogenesis and membrane fusion....

  7. Vibrio cholerae hemolysin is required for lethality, developmental delay, and intestinal vacuolation in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Hediye Nese Cinar

    Full Text Available BACKGROUND: Cholera toxin (CT and toxin-co-regulated pili (TCP are the major virulence factors of Vibrio cholerae O1 and O139 strains that contribute to the pathogenesis of disease during devastating cholera pandemics. However, CT and TCP negative V. cholerae strains are still able to cause severe diarrheal disease in humans through mechanisms that are not well understood. METHODOLOGY/PRINCIPAL FINDINGS: To determine the role of other virulence factors in V. cholerae pathogenesis, we used a CT and TCP independent infection model in the nematode Caenorhabditis elegans and identified the hemolysin A (hlyA gene as a factor responsible for animal death and developmental delay. We demonstrated a correlation between the severity of infection in the nematode and the level of hemolytic activity in the V. cholerae biotypes. At the cellular level, V. cholerae infection induces formation of vacuoles in the intestinal cells in a hlyA dependent manner, consistent with the previous in vitro observations. CONCLUSIONS/SIGNIFICANCE: Our data strongly suggest that HlyA is a virulence factor in C. elegans infection leading to lethality and developmental delay presumably through intestinal cytopathic changes.

  8. Prevalence of virulent Helicobacter pylori strains in patients affected by idiopathic dysrhythmias.

    Science.gov (United States)

    Franceschi, Francesco; Brisinda, Donatella; Buccelletti, Francesco; Ruggieri, Maria Pia; Gasbarrini, Antonio; Sorbo, Annarita; Marsiliani, Davide; Venuti, Angela; Fenici, Peter; Gasbarrini, Giovanni; Silveri, Nicolò Gentiloni; Fenici, Riccardo

    2013-06-01

    Helicobacter pylori virulent strains have been shown to affect cardiovascular diseases through molecular mimicry mechanisms. Silent autoimmune myocarditis has been hypothesized to be the cause of idiopathic dysrhythmias (IA). The aim of this study is to assess the prevalence of virulent H. pylori strains in patients affected by IA. In this study,54 patients (40 men, mean age 44 ± 17 years) affected by IA and 50 healthy subjects (34 men, mean age 45 ± 9) were evaluated. IA, defined as dysrhythmias with no evidence of other cardiac pathology, were either supraventricular (SVA, 23 patients; mean age 45 ± 15 years) or ventricular (VA, 31 patients; mean age 42 ± 18 years). H. pylori infection and gastrointestinal (GI) symptoms were evaluated. H. pylori strains expressing the cytotoxin-associated gene A (cagA) and the vacuolating-cytotoxin A (vacA) were also assessed through western blot. The prevalence of H. pylori is similar in IA patients and in controls (42 vs. 44%; p > 0.05); H. pylori infection is observed in 48 and 39% of the patients are affected by SVA and VA, respectively. The prevalence of CagA-positive strains is increased in IA patients compared to controls (65 vs. 42%; p < 0.01); similarly, the prevalence of VacA-positive strains is also increased in IA patients (74 vs. 46%; p < 0.006). Excluding belching, infected patients did not show any difference in GI symptoms, when compared to non-infected subjects. From this study it is concluded that there is an epidemiological link between CagA and VacA-positive H. pylori strains in IA patients.

  9. Organelle acidification negatively regulates vacuole membrane fusion in vivo

    Science.gov (United States)

    Desfougères, Yann; Vavassori, Stefano; Rompf, Maria; Gerasimaite, Ruta; Mayer, Andreas

    2016-01-01

    The V-ATPase is a proton pump consisting of a membrane-integral V0 sector and a peripheral V1 sector, which carries the ATPase activity. In vitro studies of yeast vacuole fusion and evidence from worms, flies, zebrafish and mice suggested that V0 interacts with the SNARE machinery for membrane fusion, that it promotes the induction of hemifusion and that this activity requires physical presence of V0 rather than its proton pump activity. A recent in vivo study in yeast has challenged these interpretations, concluding that fusion required solely lumenal acidification but not the V0 sector itself. Here, we identify the reasons for this discrepancy and reconcile it. We find that acute pharmacological or physiological inhibition of V-ATPase pump activity de-acidifies the vacuole lumen in living yeast cells within minutes. Time-lapse microscopy revealed that de-acidification induces vacuole fusion rather than inhibiting it. Cells expressing mutated V0 subunits that maintain vacuolar acidity were blocked in this fusion. Thus, proton pump activity of the V-ATPase negatively regulates vacuole fusion in vivo. Vacuole fusion in vivo does, however, require physical presence of a fusion-competent V0 sector. PMID:27363625

  10. PIKfyve Regulates Vacuole Maturation and Nutrient Recovery following Engulfment.

    Science.gov (United States)

    Krishna, Shefali; Palm, Wilhelm; Lee, Yongchan; Yang, Wendy; Bandyopadhyay, Urmi; Xu, Haoxing; Florey, Oliver; Thompson, Craig B; Overholtzer, Michael

    2016-09-12

    The scavenging of extracellular macromolecules by engulfment can sustain cell growth in a nutrient-depleted environment. Engulfed macromolecules are contained within vacuoles that are targeted for lysosome fusion to initiate degradation and nutrient export. We have shown that vacuoles containing engulfed material undergo mTORC1-dependent fission that redistributes degraded cargo back into the endosomal network. Here we identify the lipid kinase PIKfyve as a regulator of an alternative pathway that distributes engulfed contents in support of intracellular macromolecular synthesis during macropinocytosis, entosis, and phagocytosis. We find that PIKfyve regulates vacuole size in part through its downstream effector, the cationic transporter TRPML1. Furthermore, PIKfyve promotes recovery of nutrients from vacuoles, suggesting a potential link between PIKfyve activity and lysosomal nutrient export. During nutrient depletion, PIKfyve activity protects Ras-mutant cells from starvation-induced cell death and supports their proliferation. These data identify PIKfyve as a critical regulator of vacuole maturation and nutrient recovery during engulfment.

  11. Vacuole-targeting fungicidal activity of amphotericin B

    Directory of Open Access Journals (Sweden)

    Akira eOgita

    2012-03-01

    Full Text Available Invasive fungal infections are recognized as major threats to patients with immune depression as well as those with cancer chemotherapy. Amphotericin B (AmB, a classical antifungal agent with a polyene macrolide structure, is widely used for the control of serious fungal infections. However, the clinical use of this antibiotic is limited by the treatment-associated side effects and the appearance of resistant strains. AmB lethality has been generally elucidated by the alteration of plasma membrane ion permeability due to its specific binding to plasma membrane ergosterol. While, the recent studies with Saccharomyces cerevisiae and Candida albicans reveals the vacuole disruptive action as another cause of AmB lethality on the basis of its marked amplification in combination with allicin, an allyl sulfur compound from garlic. Indeed, AmB causes a serious structural damage to the vacuole membrane at a lethal concentration, and even at a non-lethal concentration in combination with allicin. Such an enhancement effect of allicin is dependent on an inhibition of ergosterol-trafficking from the plasma membrane to the vacuole membrane, which is considered to be a cellular response to protect against the vacuole membrane disintegration. Allicin can also decrease the minimum fungicidal concentration of AmB against the pathogenic fungi C. albicans and Aspergillus fumigatus, as is the case of S. cerevisiae. The synergistic fungicidal activities of AmB and allicin may have significant implications in the development of the vacuole-targeting chemotherapy against fungal infections.

  12. Listeriolysin O Membrane Damaging Activity Involves Arc Formation and Lineaction -- Implication for Listeria monocytogenes Escape from Phagocytic Vacuole.

    Directory of Open Access Journals (Sweden)

    Yi Ruan

    2016-04-01

    Full Text Available Listeriolysin-O (LLO plays a crucial role during infection by Listeria monocytogenes. It enables escape of bacteria from phagocytic vacuole, which is the basis for its spread to other cells and tissues. It is not clear how LLO acts at phagosomal membranes to allow bacterial escape. The mechanism of action of LLO remains poorly understood, probably due to unavailability of suitable experimental tools that could monitor LLO membrane disruptive activity in real time. Here, we used high-speed atomic force microscopy (HS-AFM featuring high spatio-temporal resolution on model membranes and optical microscopy on giant unilamellar vesicles (GUVs to investigate LLO activity. We analyze the assembly kinetics of toxin oligomers, the prepore-to-pore transition dynamics and the membrane disruption in real time. We reveal that LLO toxin efficiency and mode of action as a membrane-disrupting agent varies strongly depending on the membrane cholesterol concentration and the environmental pH. We discovered that LLO is able to form arc pores as well as damage lipid membranes as a lineactant, and this leads to large-scale membrane defects. These results altogether provide a mechanistic basis of how large-scale membrane disruption leads to release of Listeria from the phagocytic vacuole in the cellular context.

  13. [Helicobacter pylori and Arteriosclerosis].

    Science.gov (United States)

    Matsui, Teruaki

    2011-03-01

    Helicobacter pylori (H. pylori) infection-related diseases are known to include gastritis, gastric and duodenal ulcer, gastric cancer, gastric MALT lymphoma, idiopathic thrombocytopenic purpura, iron-deficient anemia, urticaria, reflux esophagitis, and some lifestyle-related diseases. It is indicated that homocysteine involved with arteriosclerosis induces lifestyle-related diseases. Homocysteine is decomposed to methionine and cysteine (useful substances) in the liver, through the involvement of vitamin B₁₂ (VB₁₂) and folic acid. However, deficiency of VB₁₂ and folic acid induces an increase in unmetabolized homocysteine stimulating active oxygen and promoting arteriosclerosis. VB₁₂ and folic acid are activated by the intrinsic factors of gastric parietal cells and gastric acid. The question of whether homocysteine, as a trigger of arteriosclerosis, was influenced by H. pylori infection was investigated. H. pylori infection induces atrophy of the gastric mucosa, and the function of parietal cells decreases with the atrophy to inactivate its intrinsic factor. The inactivation of the intrinsic factor causes a deficiency of VB₁₂ and folic acid to increase homocysteine's chances of triggering arteriosclerosis. The significance and usefulness of H. pylori eradication therapy was evaluated for its ability to prevent arteriosclerosis that induces lifestyle-related diseases. Persons with positive and negative results of H. pylori infection were divided into a group of those aged 65 years or more (early and late elderly) and a group of those under 65 years of age, and assessed for gastric juice. For twenty-five persons from each group who underwent gastrointestinal endoscopy, the degree of atrophy of the gastric mucosa was observed. Blood homocysteine was measured as a novel index of arteriosclerosis, as well as VB₁₂ and folic acid that affect the metabolism of homocysteine, and then activated by gastric acid and intrinsic factors. Their

  14. Helicobacter pylori infection in Japan

    Science.gov (United States)

    Shiota, Seiji; Murakawi, Kazunari; Suzuki, Rumiko; Fujioka, Toshio; Yamaoka, Yoshio

    2013-01-01

    The prevalence of Helicobacter pylori infection is gradually decreasing in Japan. On the main island of Japan, nearly all H. pylori isolates possess cagA and vacA with strong virulence. However, less virulent H. pylori strains are frequently found in Okinawa where cases of gastric cancer are the lowest in Japan. Eradication therapy for peptic ulcer, idiopathic thrombocytopenic purpura, gastric mucosa-associated lymphoid tissue lymphoma and early gastric cancer after endoscopic resection has been approved by the Japanese national health insurance system. However, the Japanese Society for Helicobacter Research recently stated that all ‘H. pylori infection’ was considered as the indication for eradication irrespective of the background diseases. To eliminate H. pylori in Japan, the Japanese health insurance system should approve the eradication of all H. pylori infections. PMID:23265147

  15. Biopatologia do Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Ladeira Marcelo Sady Plácido

    2003-01-01

    Full Text Available A infecção pelo Helicobacter pylori (H. pylori induz inflamação persistente na mucosa gástrica com diferentes lesões orgânicas em humanos, tais como gastrite crônica, úlcera péptica e câncer gástrico. Os fatores determinantes desses diferentes resultados incluem a intensidade e a distribuição da inflamação induzida pelo H. pylori na mucosa gástrica. Evidências recentes demonstram que cepas do H. pylori apresentam diversidade genotípica, cujos produtos acionam o processo inflamatório por meio de mediadores e citocinas, que podem levar a diferentes graus de resposta inflamatória do hospedeiro, resultando em diferentes destinos patológicos. Cepas H. pylori com a ilha de patogenicidade cag induzem resposta inflamatória mais grave, através da ativação da transcrição de genes, aumentando o risco para desenvolvimento de úlcera péptica e câncer gástrico. O estresse oxidativo e nitrosativo induzido pela inflamação desempenha importante papel na carcinogênese gástrica como mediador da formação ou ativação de cancerígenos, danos no DNA, bem como de alterações da proliferação celular e da apoptose.

  16. Infecciones por helicobacter pylori Helicobacter pylori infections

    Directory of Open Access Journals (Sweden)

    Liliam Alvarez Gil

    1994-02-01

    Full Text Available

    Se revisan los conocimientos sobre el papel de Helicobacter pylori en varias enfermedades gastroduodenales como la gastritis crónica (GC, úlcera gástrica (UG, úlcera duodenal (UD y dispepsia no ulcerosa (DNU. La revisión abarca aspectos históricos, microbiológicos, clínicos, epidemiológicos, diagnósticos de laboratorio, terapéuticos y de patogénesis.

    The current knowledge of the role of Helicobacter Pylori in several gastroduodenal  diseases is reviewed. It includes chronic gastritis, gastric and duodenal ulcers and nonulcerous dyspepsia. The following aspects are treated in this paper: history, microbiology. Clinical presentation, epidemiology, laboratory diagnosis, therapy and pathogenesis.

  17. Exopolysaccharide production by Helicobacter pylori

    OpenAIRE

    2006-01-01

    Helicobacter pylori is a widespread Gram-negative bacterium that infects the stomach of humans leading to the onset of several gastric disorders, such as, gastritis, gastric ulcers, and cancers. Studies from developing countries with low socioeconomic status and poor management of the drinking water suggest that it may serve as an environmental reservoir of H. pylori and therefore contribute to human infection. It has been reported that H. pylori has the ability to form microbi...

  18. Cell-free reconstitution of vacuole membrane fragmentation reveals regulation of vacuole size and number by TORC1

    Science.gov (United States)

    Michaillat, Lydie; Baars, Tonie Luise; Mayer, Andreas

    2012-01-01

    Size and copy number of organelles are influenced by an equilibrium of membrane fusion and fission. We studied this equilibrium on vacuoles—the lysosomes of yeast. Vacuole fusion can readily be reconstituted and quantified in vitro, but it had not been possible to study fission of the organelle in a similar way. Here we present a cell-free system that reconstitutes fragmentation of purified yeast vacuoles (lysosomes) into smaller vesicles. Fragmentation in vitro reproduces physiological aspects. It requires the dynamin-like GTPase Vps1p, V-ATPase pump activity, cytosolic proteins, and ATP and GTP hydrolysis. We used the in vitro system to show that the vacuole-associated TOR complex 1 (TORC1) stimulates vacuole fragmentation but not the opposing reaction of vacuole fusion. Under nutrient restriction, TORC1 is inactivated, and the continuing fusion activity then dominates the fusion/fission equilibrium, decreasing the copy number and increasing the volume of the vacuolar compartment. This result can explain why nutrient restriction not only induces autophagy and a massive buildup of vacuolar/lysosomal hydrolases, but also leads to a concomitant increase in volume of the vacuolar compartment by coalescence of the organelles into a single large compartment. PMID:22238359

  19. Vps1 in the late endosome-to-vacuole traffic

    Indian Academy of Sciences (India)

    Jacob Hayden; Michelle Williams; Ann Granich; Hyoeun Ahn; Brandon Tenay; Joshua Lukehart; Chad Highfill; Sarah Dobard; Kyoungtae Kim

    2013-03-01

    Vacuolar protein sorting 1 (Vps1), the yeast homolog to human dynamin, is a GTP hydrolyzing protein, which plays an important role in protein sorting and targeting between the Golgi and late endosomal compartments. In this study, we assessed the functional significance of Vps1 in the membrane traffic towards the vacuole. We show here that vps1 cells accumulated FM4-64 to a greater extent than wild-type (WT) cells, suggesting slower endocytic degradation traffic toward the vacuole. In addition, we observed that two endosome-to-vacuole traffic markers, DsRed-FYVE and Ste2-GFP, were highly accumulated in Vps1-deficient cells, further supporting Vps1’s implication in efficient trafficking of endocytosed materials to the vacuole. Noteworthy, a simultaneous imaging analysis in conjunction with FM4-64 pulse-chase experiment further revealed that Vps1 plays a role in late endosome to the vacuole transport. Consistently, our subcellular localization analysis showed that Vps1 is present at the late endosome. The hyperaccumulation of endosomal intermediates in the vps1 mutant cells appears to be caused by the disruption of integrity of HOPS tethering complexes, manifested by mislocalization of Vps39 to the cytoplasm. Finally, we postulate that Vps1 functions together with the Endosomal Sorting Complex Required for Transport (ESCRT) complex at the late endosomal compartments, based on the observation that the double mutants, in which VPS1 along with singular ESCRT I, II and III genes have been disrupted, exhibited synthetic lethality. Together, we propose that Vps1 is required for correct and efficient trafficking from the late endosomal compartments to the vacuole.

  20. Helicobacter pylori and pancreatic diseases

    Institute of Scientific and Technical Information of China (English)

    Milutin; Bulajic; Nikola; Panic; Johannes; Matthias; L?hr

    2014-01-01

    A possible role for Helicobacter pylori(H. pylori) infec-tion in pancreatic diseases remains controversial. H. pylori infection with antral predomination leading to an increase in pancreatic bicarbonate output and induc-ing ductal epithelial cell proliferation could contribute to the development of pancreatic cancer via complex interactions with the ABO genotype, dietary and smok-ing habits and N-nitrosamine exposure of the host. Although the individual study data available so far is inconsistent, several meta-analyses have reported an increased risk for pancreatic cancer among H. pylori seropositive individuals. It has been suggested that H. pylori causes autoimmune pancreatitis due to molecu-lar mimicry between H. pylori a-carbonic anhydrase(a-CA) and human CA type Ⅱ, and between H. pylori plasminogen-binding protein and human ubiquitin-protein ligase E3 component n-recognin 2, enzymes that are highly expressed in the pancreatic ductal andacinar cells, respectively. Future studies involving large numbers of cases are needed in order to examine the role of H. pylori in autoimmune pancreatitis more fully. Considering the worldwide pancreatic cancer burden, as well as the association between autoimmune pan-creatitis and other autoimmune conditions, a complete elucidation of the role played by H. pylori in the gen-esis of such conditions could have a substantial impact on healthcare.

  1. Helicobacter pylori lipopolysaccharide is synthesized via a novel pathway with an evolutionary connection to protein N-glycosylation.

    Directory of Open Access Journals (Sweden)

    Isabelle Hug

    2010-03-01

    Full Text Available Lipopolysaccharide (LPS is a major component on the surface of Gram negative bacteria and is composed of lipid A-core and the O antigen polysaccharide. O polysaccharides of the gastric pathogen Helicobacter pylori contain Lewis antigens, mimicking glycan structures produced by human cells. The interaction of Lewis antigens with human dendritic cells induces a modulation of the immune response, contributing to the H. pylori virulence. The amount and position of Lewis antigens in the LPS varies among H. pylori isolates, indicating an adaptation to the host. In contrast to most bacteria, the genes for H. pylori O antigen biosynthesis are spread throughout the chromosome, which likely contributed to the fact that the LPS assembly pathway remained uncharacterized. In this study, two enzymes typically involved in LPS biosynthesis were found encoded in the H. pylori genome; the initiating glycosyltransferase WecA, and the O antigen ligase WaaL. Fluorescence microscopy and analysis of LPS from H. pylori mutants revealed that WecA and WaaL are involved in LPS production. Activity of WecA was additionally demonstrated with complementation experiments in Escherichia coli. WaaL ligase activity was shown in vitro. Analysis of the H. pylori genome failed to detect a flippase typically involved in O antigen synthesis. Instead, we identified a homolog of a flippase involved in protein N-glycosylation in other bacteria, although this pathway is not present in H. pylori. This flippase named Wzk was essential for O antigen display in H. pylori and was able to transport various glycans in E. coli. Whereas the O antigen mutants showed normal swimming motility and injection of the toxin CagA into host cells, the uptake of DNA seemed to be affected. We conclude that H. pylori uses a novel LPS biosynthetic pathway, evolutionarily connected to bacterial protein N-glycosylation.

  2. VacA and cagA genotypes status and antimicrobial resistance properties of Helicobacter pylori strains isolated from meat products in Isfahan province, Iran.

    Science.gov (United States)

    Gilani, A; Razavilar, V; Rokni, N; Rahimi, E

    2017-01-01

    Although Helicobacter pylori has a significant impact on the occurrence of severe clinical syndromes, its exact ways of transmission and origin have not been identified. According to the results of some previously published articles, foods with animal origins play a substantial role in the transmission of H. pylori to humans. The present investigation was carried out to study the vacuolating cytotoxin A (vacA) and cytotoxin associated gene A (cagA) genotypes status and antibiotic resistance properties of H. pylori strains recovered from minced-meat and hamburger samples. A total of 150 meat product samples were collected from supermarkets. All samples were cultured and the susceptive colonies were then subjected to nested-PCR, PCR-based genotyping and disk diffusion methods. 11 out of 150 samples (7.33%) were positive for H. pylori. All the isolates were further identified using the nested-PCR assay. Prevalence of H. pylori in hamburger and minced-meat samples was 1.42% and 12.5%, respectively. S1a, m1a and cagA were the most commonly detected genotypes. The most commonly detected combined genotypes in the H. pylori strains of minced-meat were s1am1a (10%), s1am1b (10%) and s2m1a (10%). Helicobacter pylori strains of meat products harbored the highest levels of resistance against ampicillin (90.90%), erythromycin (72.72%), amoxicillin (72.72%), trimethoprim (63.63%), tetracycline (63.63%), and clarithromycin (63.63%). Hamburger and minced-meat samples may be the sources of virulent and resistant strains of H. pylori. Meat products are possible sources of resistant and virulent strains of H. pylori similar to those vacA and cagA genotypes. Using healthy raw materials and observation of personal hygiene can reduce the risk of H. pylori in meat products.

  3. Inactivation of Helicobacter pylori by Chloramination

    Science.gov (United States)

    Three strains of Helicobacter pylori (H. pylori) were studied to determine their resistance to chloramination. H. pylori is an organism listed on the U.S. Environmental Protection Agency’s (USEPA) Contaminant Control List (CCL). H. pylori was exposed to 2ppm of pre-formed monoc...

  4. Inactivation of Helicobacter pylori by Chloramination

    Science.gov (United States)

    Three strains of Helicobacter pylori (H. pylori) were studied to determine their resistance to chloramination. H. pylori is an organism listed on the U.S. Environmental Protection Agency’s (USEPA) Contaminant Control List (CCL). H. pylori was exposed to 2ppm of pre-formed monoc...

  5. Rimmed vacuoles in Becker muscular dystrophy have similar features with inclusion myopathies.

    Directory of Open Access Journals (Sweden)

    Kazunari Momma

    Full Text Available Rimmed vacuoles in myofibers are thought to be due to the accumulation of autophagic vacuoles, and can be characteristic in certain myopathies with protein inclusions in myofibers. In this study, we performed a detailed clinical, molecular, and pathological characterization of Becker muscular dystrophy patients who have rimmed vacuoles in muscles. Among 65 Becker muscular dystrophy patients, we identified 12 patients who have rimmed vacuoles and 11 patients who have deletions in exons 45-48 in DMD gene. All patients having rimmed vacuoles showed milder clinical features compared to those without rimmed vacuoles. Interestingly, the rimmed vacuoles in Becker muscular dystrophy muscles seem to represent autophagic vacuoles and are also associated with polyubiquitinated protein aggregates. These findings support the notion that rimmed vacuoles can appear in Becker muscular dystrophy, and may be related to the chronic changes in muscle pathology induced by certain mutations in the DMD gene.

  6. Rimmed vacuoles in Becker muscular dystrophy have similar features with inclusion myopathies.

    Science.gov (United States)

    Momma, Kazunari; Noguchi, Satoru; Malicdan, May Christine V; Hayashi, Yukiko K; Minami, Narihiro; Kamakura, Keiko; Nonaka, Ikuya; Nishino, Ichizo

    2012-01-01

    Rimmed vacuoles in myofibers are thought to be due to the accumulation of autophagic vacuoles, and can be characteristic in certain myopathies with protein inclusions in myofibers. In this study, we performed a detailed clinical, molecular, and pathological characterization of Becker muscular dystrophy patients who have rimmed vacuoles in muscles. Among 65 Becker muscular dystrophy patients, we identified 12 patients who have rimmed vacuoles and 11 patients who have deletions in exons 45-48 in DMD gene. All patients having rimmed vacuoles showed milder clinical features compared to those without rimmed vacuoles. Interestingly, the rimmed vacuoles in Becker muscular dystrophy muscles seem to represent autophagic vacuoles and are also associated with polyubiquitinated protein aggregates. These findings support the notion that rimmed vacuoles can appear in Becker muscular dystrophy, and may be related to the chronic changes in muscle pathology induced by certain mutations in the DMD gene.

  7. Halitosis and Helicobacter pylori infection.

    Science.gov (United States)

    Tangerman, A; Winkel, E G; de Laat, L; van Oijen, A H; de Boer, W A

    2012-03-01

    There is disagreement about a possible relationship between Helicobacter pylori (H. pylori) infection and objective halitosis, as established by volatile sulfur compounds (VSCs) in the breath. Many studies related to H. pylori used self-reported halitosis, a subjective and unreliable method to detect halitosis. In this study a possible relation between H. pylori and halitosis was evaluated, using an objective method (gas chromatography, GC) to detect the VSCs, responsible for the halitosis. The levels of the VSCs hydrogen sulfide (H(2)S), methyl mercaptan (MM) and dimethyl sulfide (DMS) were measured in mouth breath and in stomach air of 11 H. pylori positive patients and of 38 H. pylori negative patients, all with gastric pathology. Halitosis was also established by organoleptic scoring (OLS) of mouth-breath. The levels of H(2)S, MM and DMS in the mouth-breath and stomach air of the H. pylori positive patients did not differ significantly from those of the H. pylori negative patients. OLS of the mouth-breath resulted in 9 patients with halitosis, 1 out of the H. pylori positive group and 8 out of the H. pylori negative group, which is not statistically different. The concentrations of the VSCs in stomach air were in nearly all cases below the thresholds of objectionability of the various VSCs, indicating that halitosis does not originate in the stomach. The patients with gastric pathology were also compared with control patients without gastric pathology and with normal volunteers. No significant differences in VSCs in mouth breath were observed between these groups. Thus, in this study no association between halitosis and H. pylori infection was found. Halitosis, as established by GC and OLS, nearly always originates within the oral cavity and seldom or never within the stomach.

  8. Usefulness of Housekeeping Genes for the Diagnosis of Helicobacter pylori Infection, Strain Discrimination and Detection of Multiple Infection.

    Science.gov (United States)

    Palau, Montserrat; Kulmann, Marcos; Ramírez-Lázaro, María José; Lario, Sergio; Quilez, María Elisa; Campo, Rafael; Piqué, Núria; Calvet, Xavier; Miñana-Galbis, David

    2016-12-01

    Helicobacter pylori infects human stomachs of over half the world's population, evades the immune response and establishes a chronic infection. Although most people remains asymptomatic, duodenal and gastric ulcers, MALT lymphoma and progression to gastric cancer could be developed. Several virulence factors such as flagella, lipopolysaccharide, adhesins and especially the vacuolating cytotoxin VacA and the oncoprotein CagA have been described for H. pylori. Despite the extensive published data on H. pylori, more research is needed to determine new virulence markers, the exact mode of transmission or the role of multiple infection. Amplification and sequencing of six housekeeping genes (amiA, cgt, cpn60, cpn70, dnaJ, and luxS) related to H. pylori pathogenesis have been performed in order to evaluate their usefulness for the specific detection of H. pylori, the genetic discrimination at strain level and the detection of multiple infection. A total of 52 H. pylori clones, isolated from 14 gastric biopsies from 11 patients, were analyzed for this purpose. All genes were specifically amplified for H. pylori and all clones isolated from different patients were discriminated, with gene distances ranged from 0.9 to 7.8%. Although most clones isolated from the same patient showed identical gene sequences, an event of multiple infection was detected in all the genes and microevolution events were showed for amiA and cpn60 genes. These results suggested that housekeeping genes could be useful for H. pylori detection and to elucidate the mode of transmission and the relevance of the multiple infection. © 2016 John Wiley & Sons Ltd.

  9. Genes controlling the development and function of plant vacuoles

    NARCIS (Netherlands)

    Li, Y.

    2017-01-01

    All plant cells contain numerous organelles, like mitochondria chloroplasts, with specific functions that are generally very similar among cell types and species. However, vacuoles, which are by far the largest compartments in plant cells, show a broad diversification in shape, dimensions, content

  10. Mycoplasma pneumoniae CARDS toxin is internalized via clathrin-mediated endocytosis.

    Directory of Open Access Journals (Sweden)

    Manickam Krishnan

    Full Text Available Bacterial toxins possess specific mechanisms of binding and uptake by mammalian cells. Mycoplasma pneumoniae CARDS (Community Acquired Respiratory Distress Syndrome toxin is a 68 kDa protein, which demonstrates high binding affinity to human surfactant protein-A and exhibits specific biological activities including mono-ADP ribosylation and vacuolization. These properties lead to inflammatory processes in the airway and a range of cytopathologies including ciliostasis, loss of tissue integrity and injury, and cell death. However, the process by which CARDS toxin enters target cells is unknown. In this study, we show that CARDS toxin binds to mammalian cell surfaces and is internalized rapidly in a dose and time-dependent manner using a clathrin-mediated pathway, as indicated by inhibition of toxin internalization by monodansylcadaverine but not by methyl-β-cyclodextrin or filipin. Furthermore, the internalization of CARDS toxin was markedly inhibited in clathrin-depleted cells.

  11. Helicobacter pylori infection

    Institute of Scientific and Technical Information of China (English)

    Yvan Vandenplas

    2000-01-01

    @@ IS THERE ANYTHING NEW? Helicobacter pylori has been for many years a forgotten bacterium, since the first report on this spiral organism dated from the 19th century[1]. As early as in 1906, an association between a spiral organism and gastric carcinoma was suggested[2].Doenges reported in 1938 that on autopsy not less than 40% of human stomachs were found to be invaded by spiral organisms[3].

  12. Nitroimidazole resistance in Helicobacter pylori

    NARCIS (Netherlands)

    Van der Wouden, EJ; Thijs, JC; Van Zwet, AA; Kleibeuker, JH

    2000-01-01

    The efficacy of a nitroimidazole-containing regimen for the treatment of Helicobacter pylori infection is decreased by nitroimidazole resistance. Nitroimidazoles are metabolized by H. pylori by several nitro-reductases of which an oxygen-insensitive NADPH nitroreductase encoded by the rdxA gene is t

  13. Helicobacter pylori infection in pediatrics

    DEFF Research Database (Denmark)

    Wewer, Anne Vibeke; Kalach, Nicolas

    2003-01-01

    in gastric manifestations is the subject of conflicting reports. Extra-digestive manifestations are also reported in the course of this infection. The treatment of H. pylori infection is influenced by resistance of the bacteria to the antibiotics used. We suggest that eradication of H. pylori should take...

  14. Helicobacter pylori and Nonmalignant Diseases.

    Science.gov (United States)

    Potamitis, Georgios S; Axon, Anthony T R

    2015-09-01

    Helicobacter pylori is responsible for most peptic ulcers, plays a role in functional dyspepsia and is thought by some to influence the course of gastroesophageal reflux disease. This article addresses recent studies that have been published in connection with these diseases. H. pylori-associated peptic ulcer is declining in prevalence but the incidence of perforation and bleeding remains high especially in the elderly. All H. pylori associated peptic ulcers should be treated by eradication of the infection. Dyspepsia is a common disorder that affects up to 25% of the population. About 8% of cases that are infected with H. pylori will respond to treatment of the infection. The association between H. pylori and gastroesophageal reflux disease continues to be debated, a number of studies have shown that there is a negative association between H. pylori infection and Gastroesophageal reflux disease but treatment of H. pylori has not been shown to induce reflux or to affect the response to medication. Gastric atrophy is known to extend when acid suppression is used in infected patients implying that H. pylori treatment should be used in infected patients who are to undergo long-term Proton Pump Inhibitor therapy.

  15. Pathogenesis of Helicobacter pylori infection

    NARCIS (Netherlands)

    J.G. Kusters (Johannes); A.H.M. van Vliet (Arnoud); E.J. Kuipers (Ernst)

    2006-01-01

    textabstractHelicobacter pylori is the first formally recognized bacterial carcinogen and is one of the most successful human pathogens, as over half of the world's population is colonized with this gram-negative bacterium. Unless treated, colonization usually persists lifelong. H. pylori infection

  16. Epidemiology of Helicobacter pylori infection.

    Science.gov (United States)

    Eusebi, Leonardo H; Zagari, Rocco M; Bazzoli, Franco

    2014-09-01

    Medline and PubMed databases were searched on epidemiology of Helicobacter pylori for the period of April 2013-March 2014. Several studies have shown that the prevalence of H. pylori is still high in most countries. In north European and North American populations, about one-third of adults are still infected, whereas in south and east Europe, South America, and Asia, the prevalence of H. pylori is often higher than 50%. H. pylori remains highly prevalent in immigrants coming from countries with high prevalence of H. pylori. However, the lower prevalence of infection in the younger generations suggests a further decline of H. pylori prevalence in the coming decades. Low socioeconomic conditions in childhood are confirmed to be the most important risk factors for H. pylori infection. Although the way the infection is transmitted is still unclear, interpersonal transmission appears to be the main route. Finally, H. pylori recurrence after successful eradication can still occur, but seems to be an infrequent event.

  17. Protein delivery to vacuole requires SAND protein-dependent Rab GTPase conversion for MVB-vacuole fusion

    NARCIS (Netherlands)

    Singh, M.K.; Krüger, F.; Beckmann, H.; Brumm, S.; Vermeer, J.E.M.; Munnik, T.; Mayer, U.; Stierhof, Y.D.; Grefen, C.; Schumacher, K.; Jürgens, G.

    2014-01-01

    Plasma-membrane proteins such as ligand-binding receptor kinases, ion channels, or nutrient transporters are turned over by targeting to a lytic compartment--lysosome or vacuole--for degradation. After their internalization, these proteins arrive at an early endosome, which then matures into a late

  18. Helicobacter pylori in gastroduodenal perforation

    Directory of Open Access Journals (Sweden)

    Bharat B Dogra

    2014-01-01

    Full Text Available Background:peptic ulcers were earlier believed to be caused by dietary factors, gastric acid, and stress. However, in 1983, Warren and Marshall identified the correlation between Helicobacter pylori (H. pylori and peptic ulcers. It is now well established that most of the peptic ulcers occur as a result of H. pylori infection. But the co-relation between perforated peptic ulcer and H. pylori infection is not yet fully established. Aims and objectives : to study the prevalence of H. pylori infection in patients with perforated peptic ulcer. Materials and methods: this was a prospective study carried out in all cases of perforated peptic ulcer reporting in surgical wards of a medical college during 2008-2010. A total of 50 cases, presenting as acute perforation of duodenum and stomach during this period, formed the study group. After resuscitation, all the cases were subjected to emergency exploratory laparotomy. The exact site of perforation was identified, biopsy was taken from the ulcer margin from 2-3 sites and the tissue was sent for H. pylori culture and histopathological examination. Simple closure of perforation, omentoplasty, thorough peritoneal lavage and drainage was carried out. Results: out of the 50 cases of perforated peptic ulcer, 38 happened to be males, and only 12 were females. The age of the patients ranged from 20 to 70 years. All the patients underwent only emergency laparotomy. As many as 46 cases (92% turned out to be positive for H. pylori and only four cases (8% were negative for this infection. Postoperatively, patients who were found to be positive for H. pylori were put on anti-H. pylori treatment. Conclusion: there was a high prevalence of H. pylori infection in patients with perforated gastroduodenal ulcers.

  19. Helicobacter pylori vacA genotypes and cagA status and their relationship to associated diseases

    Institute of Scientific and Technical Information of China (English)

    Peng Hou; Zhen Xing Tu; Guo Ming Xu; Yan Fang Gong; Xu Hui Ji; Zhao Shen Li

    2000-01-01

    Helicobacter pylori (H. pylori ) is a major causativebacterium of chronic gastritis, peptic ulcer and mucosaassociated lymphoid tissue lymphoma in humans, and associated with an increased risk of gastric cancer[1 -8]. An important virulant factor of H. pylori is the vacuolating cytotoxin ( VacA ) encoded by vacA that induces cytoplasmic vacuolation in target cells both in vitro and in vivo[9-11]. VacA is produced as a 140 kDa precursor which contains an N-terminal signal peptide and an approximately 33 kDa C-terminal outer membrance exporter. The precursor is cleaved at both N-terminal and C-terminal and secreted into the extracellular milieu as a 95 kDa mature protein. The mature protein futher undergoes specific cleavage to yield 37 kDa and 58 kDa subunits[12-14] Although vacA is present in all H. pylori strains, only about 50% to 60% of strains can induce vacuolation of epithelial cells as assessed by the HeLa cell assay. vacA shows considerable genetic variation in H. pylori isolated from all over the world and contains at least two variable regions. The s region exists as sl or s2 allelic types. Among type sl strains, subtypes sla and slb have been identified. The m region occurs as ml or m2 allelic types. Specific vacA genotype of H. pylori strains are associated with the production of the cytotoxin in vitro, epithelial damage in vivo, and clinical consequences[15-27]. The other virulant factor is the cytotoxin-associated protein (CagA) encoded by the cytotoxin-associated gene (cagA). The cagA gene is present in about 60% to 70% of strains and all of these strains express the cagA. The presence of cagA is also associated with the production of the cytotoxin in vitro, and clinical outcome[24-30]. The aim of this study was (i) to identify vacA genotypes and cagA status of H. pylori isolated from Chinese patients; (ii) to evaluation the relatioship beween vacA genotypes, cagA status and related gastroenterological disorders.

  20. Expression of the CagA gene of H. pylori and application of its product

    Institute of Scientific and Technical Information of China (English)

    Feng Chan Han; Xiao Jun Yan; Cheng Zhi Su

    2000-01-01

    @@ INTRODUCTION Helicobacter pylori (Hp) plays an important role in the upper digestive tract diseases. It can be divided into two main groups (toxic and non-toxic Hp )according to the production of vacuolating cytotoxin (VacA). The toxic bacteria also produce cytotoxin associated protein A (CagA) which might have something to do with the transcription, folding,transportation or the function of VacA. Studies showed that CagA positive Hp ( CagA+ Hp )accounted for more than 50% of all kinds of Hp,and peptic ulcer and gastric cancer were closely related to their infection[1-7].

  1. Bacterial glycosyltransferase toxins.

    Science.gov (United States)

    Jank, Thomas; Belyi, Yury; Aktories, Klaus

    2015-12-01

    Mono-glycosylation of host proteins is a common mechanism by which bacterial protein toxins manipulate cellular functions of eukaryotic target host cells. Prototypic for this group of glycosyltransferase toxins are Clostridium difficile toxins A and B, which modify guanine nucleotide-binding proteins of the Rho family. However, toxin-induced glycosylation is not restricted to the Clostridia. Various types of bacterial pathogens including Escherichia coli, Yersinia, Photorhabdus and Legionella species produce glycosyltransferase toxins. Recent studies discovered novel unexpected variations in host protein targets and amino acid acceptors of toxin-catalysed glycosylation. These findings open new perspectives in toxin as well as in carbohydrate research.

  2. Targeting bacterial toxins.

    Science.gov (United States)

    Ivarsson, Mattias E; Leroux, Jean-Christophe; Castagner, Bastien

    2012-04-23

    Protein toxins constitute the main virulence factors of several species of bacteria and have proven to be attractive targets for drug development. Lead candidates that target bacterial toxins range from small molecules to polymeric binders, and act at each of the multiple steps in the process of toxin-mediated pathogenicity. Despite recent and significant advances in the field, a rationally designed drug that targets toxins has yet to reach the market. This Review presents the state of the art in bacterial toxin targeted drug development with a critical consideration of achieved breakthroughs and withstanding challenges. The discussion focuses on A-B-type protein toxins secreted by four species of bacteria, namely Clostridium difficile (toxins A and B), Vibrio cholerae (cholera toxin), enterohemorrhagic Escherichia coli (Shiga toxin), and Bacillus anthracis (anthrax toxin), which are the causative agents of diseases for which treatments need to be improved. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Isocitrate dehydrogenase of Helicobacter pylori potentially induces humoral immune response in subjects with peptic ulcer disease and gastritis.

    Directory of Open Access Journals (Sweden)

    M Abid Hussain

    Full Text Available BACKGROUND: H. pylori causes gastritis and peptic ulcers and is a risk factor for the development of gastric carcinoma. Many of the proteins such as urease, porins, flagellins and toxins such as lipo-polysaccharides have been identified as potential virulence factors which induce proinflammatory reaction. We report immunogenic potentials of isocitrate dehydrogenase (ICD, an important house keeping protein of H. pylori. METHODOLOGY/PRINCIPAL FINDINGS: Amino acid sequences of H. pylori ICD were subjected to in silico analysis for regions with predictably high antigenic indexes. Also, computational modelling of the H. pylori ICD as juxtaposed to the E. coli ICD was carried out to determine levels of structure similarity and the availability of surface exposed motifs, if any. The icd gene was cloned, expressed and purified to a very high homogeneity. Humoral response directed against H. pylori ICD was detected through an enzyme linked immunosorbent assay (ELISA in 82 human subjects comprising of 58 patients with H. pylori associated gastritis or ulcer disease and 24 asymptomatic healthy controls. The H. pylori ICD elicited potentially high humoral immune response and revealed high antibody titers in sera corresponding to endoscopically-confirmed gastritis and ulcer disease subjects. However, urea-breath-test negative healthy control samples and asymptomatic control samples did not reveal any detectable immune responses. The ELISA for proinflammatory cytokine IL-8 did not exhibit any significant proinflammatory activity of ICD. CONCLUSIONS/SIGNIFICANCE: ICD of H. pylori is an immunogen which interacts with the host immune system subsequent to a possible autolytic-release and thereby significantly elicits humoral responses in individuals with invasive H. pylori infection. However, ICD could not significantly stimulate IL8 induction in a cultured macrophage cell line (THP1 and therefore, may not be a notable proinflammatory agent.

  4. Helicobacter pylori in lacrimal secretions.

    Science.gov (United States)

    Batioglu-Karaaltin, Aysegul; Saatci, Ozlem; Akpinar, Meltem; Celik, Melih Ozgür; Develioglu, Omer; Yigit, Ozgur; Külekçi, Mehmet; Akarsubaşı, Alper Tunga

    2016-03-01

    The aim of this study was to investigate the presence of Helicobacter pylori in human lacrimal and nasal secretions. Eighty patients with complaints of dyspepsia who had undergone endoscopies and gastric antrum biopsies were included in the study. A total of five specimens, including 2 lacrimal secretion samples, 2 nasal mucosal swab samples, and 1 gastric antrum biopsy, were collected from each patient and investigated with polymerase chain reaction (PCR) methods consisting of the urease enzyme coding gene GlmM (UreC) and the H pylori-specific 16S rRNA coding gene. The Reflux Symptom Index and ophthalmologic complaints of the patients were recorded. The detected positivity rates of the H pylori 16S rRNA coding gene in gastric biopsies and nasal mucous and lacrimal secretions were 55, 11.2, and 20%, respectively. The patients were grouped as gastric-antrum-biopsy-negative (Group I [n = 36]) and -positive (Group II [n = 44). In Group II, H pylori positivity in the lacrimal and nasal mucous secretions was 36.3 and 18%, respectively. A comparison between the groups in terms of H pylori presence in nasal mucous and lacrimal secretions yielded statistically significant differences (p = 0.0001, p = 0.003). The simultaneous presence of H pylori in nasal mucous and lacrimal secretions was 13.6% in Group II. H pylori positivity in nasal mucous and lacrimal secretions had a positive moderate correlation (r = 0.40; p = 0.0003). The present study is the first report on the presence of H pylori in lacrimal secretions through nested PCR, which suggested the presence of a number of mechanisms for H pylori transmission to lacrimal secretions.

  5. Characteristics of weak base-induced vacuoles formed around individual acidic organelles.

    Science.gov (United States)

    Hiruma, Hiromi; Kawakami, Tadashi

    2011-01-01

    We have previously found that the weak base 4-aminopyridine induces Brownian motion of acidic organelles around which vacuoles are formed, causing organelle traffic disorder in neurons. Our present study investigated the characteristics of vacuoles induced by weak bases (NH(4)Cl, aminopyridines, and chloroquine) using mouse cells. Individual vacuoles included acidic organelles identified by fluorescent protein expression. Mitochondria and actin filaments were extruded outside the vacuoles, composing the vacuole rim. Staining with amine-reactive fluorescence showed no protein/amino acid content in vacuoles. Thus, serous vacuolar contents are probably partitioned by viscous cytosol, other organelles, and cytoskeletons, but not membrane. The weak base (chloroquine) was immunochemically detected in intravacuolar organelles, but not in vacuoles. Early vacuolization was reversible, but long-term vacuolization caused cell death. The vacuolization and cell death were blocked by the vacuolar H(+)-ATPase inhibitor and Cl--free medium. Staining with LysoTracker or LysoSensor indicated that intravacuolar organelles were strongly acidic and vacuoles were slightly acidic. This suggests that vacuolization is caused by accumulation of weak base and H(+) in acidic organelles, driven by vacuolar H(+)-ATPase associated with Cl(-) entering, and probably by subsequent extrusion of H(+) and water from organelles to the surrounding cytoplasm.

  6. Vitrification Increased Vacuolization of Human Spematozoa: Application of MSOME Technology.

    Science.gov (United States)

    Taherzadeh, Sara; Khalili, Mohammad Ali; Agha-Rahimi, Azam; Anbari, Fateme; Ghazali, Shahin; Macchiarelli, Guido

    2017-01-01

    Sperm vitrification is a technique of ice and cryoprotectant free cryopreservation by direct plunging of sperm suspension into liquid nitrogen (LN2). The aim of this study was to investigate the influence of cryoprotectant free-vitrification on human sperm fine structure by MSOME technology and the fertility potential by zona binding assay (ZBA). 20 normo-ejaculates were prepared by swim up technique, and supernatants were divided into two parts of fresh and vitrified groups. For vitrification, sperm was dropped into LN2. Sperm motility, morphology, viability and MSOME were evaluated for each sample. In MSOM morphologically normal sperm (class 1), ≤2 small vacuoles (class 2), and one large vacuole or >2 small vacuoles (class 3) were evaluated. Also, fertility potential was evaluated by zona binding assay. Data was analyzed using paired t-test or Willcoxon's test and p-value <0.05 was considered significant. Vitrification significantly reduced both progressive motility, viability and morphology. Also, normal morphology of spermatozoa decreased significantly after vitrification. In MSOME evaluation, normal motile spermatozoa (Class 1) decreased from 23.00±12.44 to 16.00.56±10.79 after vitrification (p=0.008). Although spermatozoa classes 2 and 3 were increased, the difference was not significant. Moreover, fertility potential of motile spermatozoa was reduced after vitrification (9.0±13.87 vs. 13.40±22.73; p=0.07). Vitrification increased the rate of vacuolization in motile sperm head. Therefore, MSOME technology is recommended for assessment of sperm fine morphology in ICSI program used cryopreserved spermatozoa.

  7. Shigella subverts the host recycling compartment to rupture its vacuole.

    Science.gov (United States)

    Mellouk, Nora; Weiner, Allon; Aulner, Nathalie; Schmitt, Christine; Elbaum, Michael; Shorte, Spencer L; Danckaert, Anne; Enninga, Jost

    2014-10-08

    Shigella enters epithlial cells via internalization into a vacuole. Subsequent vacuolar membrane rupture allows bacterial escape into the cytosol for replication and cell-to-cell spread. Bacterial effectors such as IpgD, a PI(4,5)P2 phosphatase that generates PI(5)P and alters host actin, facilitate this internalization. Here, we identify host proteins involved in Shigella uptake and vacuolar membrane rupture by high-content siRNA screening and subsequently focus on Rab11, a constituent of the recycling compartment. Rab11-positive vesicles are recruited to the invasion site before vacuolar rupture, and Rab11 knockdown dramatically decreases vacuolar membrane rupture. Additionally, Rab11 recruitment is absent and vacuolar rupture is delayed in the ipgD mutant that does not dephosphorylate PI(4,5)P₂ into PI(5)P. Ultrastructural analyses of Rab11-positive vesicles further reveal that ipgD mutant-containing vacuoles become confined in actin structures that likely contribute to delayed vacular rupture. These findings provide insight into the underlying molecular mechanism of vacuole progression and rupture during Shigella invasion.

  8. Leishmania amazonensis Engages CD36 to Drive Parasitophorous Vacuole Maturation.

    Directory of Open Access Journals (Sweden)

    Kendi Okuda

    2016-06-01

    Full Text Available Leishmania amastigotes manipulate the activity of macrophages to favor their own success. However, very little is known about the role of innate recognition and signaling triggered by amastigotes in this host-parasite interaction. In this work we developed a new infection model in adult Drosophila to take advantage of its superior genetic resources to identify novel host factors limiting Leishmania amazonensis infection. The model is based on the capacity of macrophage-like cells, plasmatocytes, to phagocytose and control the proliferation of parasites injected into adult flies. Using this model, we screened a collection of RNAi-expressing flies for anti-Leishmania defense factors. Notably, we found three CD36-like scavenger receptors that were important for defending against Leishmania infection. Mechanistic studies in mouse macrophages showed that CD36 accumulates specifically at sites where the parasite contacts the parasitophorous vacuole membrane. Furthermore, CD36-deficient macrophages were defective in the formation of the large parasitophorous vacuole typical of L. amazonensis infection, a phenotype caused by inefficient fusion with late endosomes and/or lysosomes. These data identify an unprecedented role for CD36 in the biogenesis of the parasitophorous vacuole and further highlight the utility of Drosophila as a model system for dissecting innate immune responses to infection.

  9. In vitro activity of Aloe vera inner gel against Helicobacter pylori strains.

    Science.gov (United States)

    Cellini, L; Di Bartolomeo, S; Di Campli, E; Genovese, S; Locatelli, M; Di Giulio, M

    2014-07-01

    Aloe barbadensis Miller (Aloe vera) is a herbal remedy widely used for a variety of illnesses; A. vera leaf extracts have been promoted for detoxification, cure constipation, help flush out toxins and wastes from the body, promote digestion and are used in the treatment of peptic ulcer for cytoprotective action. The aim of this study was to evaluate the antibacterial activity of A. vera inner gel against both susceptible and resistant Helicobacter pylori strains isolated in Abruzzo region, Italy. The inner gel of leaves of a 5-year-old plant of A. vera was extracted, homogenized and tested from 800 to 1.56 mg ml(-1) against 14 clinical strains and one reference strain of H. pylori using the broth microdilution methodology. Furthermore, the sample of A. vera was investigated for the chemical fingerprint of anthraquinones. The inhibitory concentrations of A. vera inner gel were similar to the bactericidal ones, with values ranging from 6.25 to 800 mg ml(-1) . Fifty per cent of the detected strains, independently of their susceptibility profile, were inhibited in their growth at 100 mg ml(-1) . Aloe vera inner gel expresses antibacterial properties against H. pylori and, therefore, in combination with antibiotics, could represent a novel strategy for the treatment of the infection of H. pylori, especially in cases of multiresistance. The study demonstrates that the Aloe vera inner gel expresses antibacterial properties against both susceptible and resistant Helicobacter pylori strains. These findings may impact on the antimicrobial resistance phenomenon of H. pylori, proposing the A. vera inner gel as a novel effective natural agent for combination with antibiotics for the treatment of H. pylori gastric infection. © 2014 The Society for Applied Microbiology.

  10. A systematic review on the association between the Helicobacter pylori vacA i genotype and gastric disease.

    Science.gov (United States)

    Liu, Xian; He, Bangshun; Cho, William C; Pan, Yuqin; Chen, Jie; Ying, Houqun; Wang, Feng; Lin, Kang; Peng, Hongxin; Wang, Shukui

    2016-05-01

    Helicobacter pylori (H. pylori) has been recognized as a cause of gastrointestinal diseases and progress of the pathology of gastrointestinal diseases is related to the genotype of H. pylori. Published studies have indicated that the H. pylori vacuolating cytotoxin gene A (vacA) i1/i2 genotype is associated with peptic ulcer disease (PUD) and gastric cancer (GC), but their conclusions are inconsistent. This study aimed to further assess the risk of vacA i gene for PUD and/or GC. A systematic search was conducted across three main electronic databases (PubMed, Web of Science, and CNKI). A meta-analysis was then performed on the pooled data of the published articles to estimate the overall influence of vacA i polymorphisms on PUD and/or GC by crude odds ratio (OR) with 95% confidence intervals (CI). The reliability of the results were confirmed by publication bias and sensitivity analysis of included studies. A total of 14 studies were selected according to the specific inclusion and exclusion criteria. The pooled results revealed that patients with GC were more vulnerable to infection by H. pylori i1 genotype (OR = 5.12; 95% CI: 2.66-9.85; P gastritis or nonulcer disease. Moreover, the results of subgroup analysis indicated that the i1 genotype of H. pylori was associated with an increased GC risk (OR = 10.89; 95% CI: 4.11-20.88; P < 0.001) in the Middle Asian population. The H. pylori vacA i1 genotype is associated with an increased GC risk, especially in the Middle Asian population.

  11. [Helicobacter pylori -- 2014].

    Science.gov (United States)

    Buzás, György Miklós

    2015-02-08

    The author reviews the main achievements in Helicobacter pylori research in the past 2 years. Of the more than 1000 microRNAs described thus far, sets of over- and underexpressed samples were identified that are associated with either gastric cancer or precancerous lesions, and some of them could be either markers or therapeutic targets in the near future. Meta-analyses involved 95 new publications: the association between infection and oesophageal, colorectal, pancreatic and liver carcinomas is supported by the increased odds ratios, but the results do not reach the strength seen in gastric carcinoma. Epstein-Barr virus is an emerging pathogen: 10% of gastric cancers are virus-associated; the prevalence of the virus in normal mucosa, chronic gastritis and peptic ulcer are currently being studied. Current Helicobacter pylori eradication regimens frequently achieve suboptimal results: a few optimisation methods are presented, although not all are supported by the meta-analyses. In 2013, the European Helicobacter Study Group proposed the development of a pan-European registry; data from 5792 patients registered so far indicated that many therapeutic regimens resulted in a low eradication rate. In 2013, the Healthy Stomach Initiative was started with the aim of supporting and disseminating research performed in the field of healthy and diseased stomachs.

  12. Helicobacter pylori infection in pediatrics

    DEFF Research Database (Denmark)

    Wewer, Anne Vibeke; Kalach, Nicolas

    2003-01-01

    A high prevalence and early colonization of Helicobacter pylori infection in childhood was described again this year in developing countries in contrast to developed ones. Upper gastrointestinal endoscopy including gastric biopsies remains the diagnostic gold standard method for this infection...

  13. Management of Helicobacter pylori infections

    NARCIS (Netherlands)

    Abadi, Amin Talebi Bezmin; Kusters, Johannes G

    2016-01-01

    BACKGROUND: Infection with Helicobacter pylori is associated with severe digestive diseases including chronic gastritis, peptic ulcer disease, and gastric cancer. Successful eradication of this common gastric pathogen in individual patients is known to prevent the occurrence of peptic ulcer disease

  14. Management of Helicobacter pylori infections

    NARCIS (Netherlands)

    Abadi, Amin Talebi Bezmin; Kusters, Johannes G

    2016-01-01

    BACKGROUND: Infection with Helicobacter pylori is associated with severe digestive diseases including chronic gastritis, peptic ulcer disease, and gastric cancer. Successful eradication of this common gastric pathogen in individual patients is known to prevent the occurrence of peptic ulcer disease

  15. Cell vacuolation induced by Haemophilus influenzae supernatants in HEp-2 cells

    Directory of Open Access Journals (Sweden)

    Maria del Rosario Espinoza-Mellado

    2013-12-01

    Full Text Available Haemophilus influenzae belongs to respiratory tract microbiota. We observed vacuoles formation in previous studies with H. influenzae culture supernatants, so in this work we characterised that cytotoxic effect. We observed an abundant production of acidic cytoplasmic vacuoles due to the presence of a “vacuolating factor” in H. influenzae supernatants which was characterised as thermolabile. Greatest vacuolating activity was observed when utilizing the fraction > 50 kDa. The presence of a large number of vacuoles in HEp-2 cells was verified by transmission electron microscopy and some vacuoles were identified with a double membrane and/or being surrounded by ribosomes. These results suggest similar behaviour to that of vacuolating effects described by autotransporter proteins an undescribed cytotoxic effect induced by H. influenzae .

  16. Anti-CagA IgG Antibody is Independent from Helicobacter pylori vacA and cagA Genotypes

    Directory of Open Access Journals (Sweden)

    Hashem Fakhre Yaseri

    2015-12-01

    Full Text Available Background: Helicobacter pylori strains have two classical virulence genes, the cytotoxinassociated A (cagA gene and the vacuolating cytotoxin A (vacA gene, which are located in thecag pathogenicity island (cagPAI. Serum immunoglobulin G (IgG antibodies to H. pylori,especially, the CagA antigen may be a reliable marker for selection of dyspeptic patients for upperendoscopy.Methods: Serum sample of 129 dyspeptic patients with positive H. pylori, were tested for serumIgG Anti-CagA antibody by ELISA. The presence of the cagA and vacA genotypes weredetermined using polymerase chain reaction (PCR on biopsy samples taken via endoscopy.Results: Positive serum IgG anti-CagA antibodies in patients with cagA+/vacA+ and cagA+/vacA- genotypes were 22/23 (95.6% and 18/19 (94.7%, respectively. In addition, serum IgG anti-CagAantibodies in patients with cagA-/vacA+ and cagA-/vacA- genotypes were 22/47 (46.8% and 33/40(82.5%, respectively.Conclusions: It can be concluded that the serum IgG anti-CagA antibody alone could selectpatients with dyspepsia following upper endoscopy. The assessment of vacuolating cytotoxinactivity of H. Pylori is, therefore, not required, even when vacA gene is positive. This hypothesisneeds to be studied in a large number of patients with dyspepsia.

  17. The Forgotten Virulence Factor: The 'non-conventional' Hemolysin TlyA And Its Role in Helicobacter pylori Infection.

    Science.gov (United States)

    Javadi, Mohammad Bagher; Katzenmeier, Gerd

    2016-12-01

    Helicobacter pylori is a human-specific Gram-negative pathogenic bacterium which colonizes the gastric mucosal layer in the stomach causing diseases such as peptic ulcer, adenocarcinoma, and gastric lymphoma. It is estimated that approximately half of the world's population is infected with H. pylori making it the most intensively characterized microbial pathogen up to now. Hemolysis has been suggested to significantly contribute to colonization of the stomach and disease progression by H. pylori. In a number of earlier studies, TlyA was characterized as a putative pore-forming cytolysin. Although a few observations in the literature suggest a role for TlyA as significant virulence factor of H. pylori, the molecular and structural characterization of this protein is much curtailed at present. Given the intensive characterization of numerous H. pylori virulence factors over the past decade, surprisingly little information exists for the TlyA toxin and its significance for pathogenesis. This review provides a brief overview on microbial hemolysis and its role for pathogenesis and discusses recent research efforts aimed at an improved understanding of the role of the 'non-conventional' hemolysin and its associated RNA methyltransferase TlyA from H. pylori.

  18. Comparative genomics of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Quan-Jiang Dong; Qing Wang; Ying-Nin Xin; Ni Li; Shi-Ying Xuan

    2009-01-01

    Genomic sequences have been determined for a number of strains of Helicobacter pylori (H pylori) and related bacteria.With the development of microarray analysis and the wide use of subtractive hybridization techniques,comparative studies have been carried out with respect to the interstrain differences between H pylori and inter-species differences in the genome of related bacteria.It was found that the core genome of H pylori constitutes 1111 genes that are determinants of the species properties.A great pool of auxillary genes are mainly from the categories of cag pathogenicity islands,outer membrane proteins,restriction-modification system and hypothetical proteins of unknown function.Persistence of H pylori in the human stomach leads to the diversification of the genome.Comparative genomics suggest that a host jump has occurs from humans to felines.Candidate genes specific for the development of the gastric diseases were identified.With the aid of proteomics,population genetics and other molecular methods,future comparative genomic studies would dramatically promote our understanding of the evolution,pathogenesis and microbiology of H pylori.

  19. Helicobacter pylori in gastric carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Hyo; Jun; Ahn; Dong; Soo; Lee

    2015-01-01

    Gastric cancer still is a major concern as the third most common cancer worldwide, despite declining rates of incidence in many Western countries. Helicobacter pylori(H. pylori) is the major cause of gastric carcinogenesis, and its infection insults gastric mucosa leading to theoccurrence of atrophic gastritis which progress to intestinal metaplasia, dysplasia, early gastric cancer, and advanced gastric cancer consequently. This review focuses on multiple factors including microbial virulence factors, host genetic factors, and environmental factors, which can heighten the chance of occurrence of gastric adenocarcinoma due to H. pylori infection. Bacterial virulence factors are key components in controlling the immune response associated with the induction of carcinogenesis, and cag A and vac A are the most well-known pathogenic factors. Host genetic polymorphisms contribute to regulating the inflammatory response to H. pylori and will become increasingly important with advancing techniques. Environmental factors such as high salt and smoking may also play a role in gastric carcinogenesis. It is important to understand the virulence factors, host genetic factors, and environmental factors interacting in the multistep process of gastric carcinogenesis. To conclude, prevention via H. pylori eradication and controlling environmental factors such as diet, smoking, and alcohol is an important strategy to avoid H. pylori-associated gastric carcinogenesis.

  20. Does Helicobacter pylori affect portal hypertensive gastropathy?

    Directory of Open Access Journals (Sweden)

    Al Mofleh Ibrahim

    2007-01-01

    Full Text Available Helicobacter pylori (H. pylori is a major etiological factor of peptic ulcer disease (PUD. It is supposed to be a risk factor for the more frequently encountered PUD in patients with liver cirrhosis. Several investigators have evaluated the effect of H. pylori on liver cirrhosis, portal hypertensive gastropathy (PHG and encephalopathy with controversial results. Some reports have shown a higher seroprevalence and suggested a synergistic effect of H. pylori on liver cirrhosis and PHG. However, this increased prevalence is associated with a negative histology and is not influenced by the cause of cirrhosis, PHG, Child class or gender. Most studies have not found any correlation between H. pylori and PHG. In contrast, other studies have reported a markedly lower prevalence of H. pylori in cirrhotics with duodenal ulcer compared to controls. The aim of this article is to review the relationship between H. pylori infection and portal hypertensive gastropathy and the role of H. pylori eradication in cirrhotic patients.

  1. Helicobacter pylori infection- recent developments in diagnosis

    National Research Council Canada - National Science Library

    Ana Isabel Lopes Filipa F Vale Mónica Oleastro

    2014-01-01

    Considering the recommended indications for Helicobacter pylori(H.pylori)eradication therapy and the broad spectrum of available diagnostic methods,a reliable diagnosis is mandatory both before and after eradication...

  2. What Do We Do about Helicobacter pylori?

    Directory of Open Access Journals (Sweden)

    CJ Hawkey

    1999-01-01

    Full Text Available Heliobacter pylori and nonsteroidal anti-inflammatory drugs (NSAIDs cause ulcers by different mechanisms. Under some circumstances, patients infected with H pylori may be less prone to NSAID-associated ulcers than those who are H pylori-negative. Eradication trials have yielded differing results. However, those who have studied patients who have a past history of ulcer disease and are already established on NSAIDs have shown no benefit from H pylori eradication.

  3. Non-pharmacological treatment of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Haim Shmuely; Noam Domniz; Jacob Yahav

    2016-01-01

    Many food and plant extracts have shown in vitro antiHelicobacter pylori(H.pylori)activity,but are less effective in vivo.The anti-H.pylori effects of these extracts are mainly permeabilitization of the membrane,anti-adhesion,inhibition of bacterial enzymes andbacterial grown.We,herein,review treatment effects of cranberry,garlic,curcumin,ginger and pistacia gum against H.pylori in both in vitro,animal studies and in vivo studies.

  4. Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Leila Hasanzadeh

    2013-07-01

    Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

  5. Helicobacter pylori Seropositivity in Children With Asthma

    OpenAIRE

    Yousefichaijan; Mosayebi; Sharafkhah; Kahbazi; Heydarbagi; Rafiei

    2016-01-01

    Background Some studies have reported an association between Helicobacter pylori (H. pylori) colonization and the occurrence of asthma or other allergies. However, data are inconsistent, and few studies have been performed in children. Objectives The current study aimed to investigate H. pylori seropositivity in children with and without asthma. Patients and Methods This cross-sect...

  6. Inflammation, immunity, and vaccines for Helicobacter pylori

    DEFF Research Database (Denmark)

    D'Elios, Mario M; Andersen, Leif P

    2009-01-01

    Helicobacter pylori infects almost half of the population worldwide and represents the major cause of gastroduodenal diseases, such as duodenal and gastric ulcer, gastric adenocarcinoma, autoimmune gastritis, and B-cell lymphoma of mucosa-associated lymphoid tissue. Helicobacter pylori induces th...... vaccine for H. pylori that will represent a novel and very important bullet against both infection and gastric cancer....

  7. Thioploca spp: filamentous sulfur bacteria with nitrate vacuoles

    DEFF Research Database (Denmark)

    Jørgensen, BB; Gallardo, VA

    1999-01-01

    communities of large Thioploca species live along the Pacific coast of South America and in other upwelling areas of high organic matter sedimentation with bottom waters poor in oxygen and rich in nitrate. Each cell of these thioplocas harbors a large liquid vacuole which is used as a storage for nitrate...... with a concentration of lip to 506 mM. The nitrate is used as an electron acceptor for sulfide oxidation and the bacteria may grow autotrophically or mixotrophically using acetate or other organic molecules as carbon source. The filaments stretch up into the overlying seawater, from which they take up nitrate...

  8. High Frequency of cagA and vacA s1a/m2 Genotype among Helicobacter pylori Infected Gastric Biopsies of Pakistani Children

    Directory of Open Access Journals (Sweden)

    Ahmed, S.

    2011-01-01

    Full Text Available The vacuolating cytotoxin VacA and cytotoxin associated gene product CagA, encoded by vacA and cagA are major virulence determinants associated with pathogenesis of Helicobacter pylori. The presence and prevalence of two major H. pylori virulence associated genes among gastric biopsies of Pakistani children were investigated in the current study. Fifty one gastric biopsy specimens of children were analysed for 16S rRNA, vacA and cagA genes using PCR. The results showed that 21 (41.2% biopsies were positive for H. pylori as determined by 16S rRNA PCR. In the 21 H. pylori positive gastric biopsies, 19 (90.5% showed vacA s1a, 1 (4.75% was vacA s1b and 1 (4.75% was vacA s2 whereas, 5 (23.8% were vacA m1 and 16 (76.2% were vacA m2. None of the H. pylori positive biopsies carried vacA s1c subtype. The cagA gene was found in 13 (61.9% of H. pylori infected biopsies and different vacA combinations were found with or without cagA gene. H. pylori was detected with high frequency of cagA while vacA s1a and vacA m2 regions with vacA s1a/m2 genotype were predominant in H. pylori infected gastric biopsies of children.

  9. 幽门螺杆菌的CagA和VacA的致病机制及其临床意义%Pathogenic mechanism of CagA and VacA produced by Helicobacter pylori and its clinical significance

    Institute of Scientific and Technical Information of China (English)

    梅峰; 周志华; 凌娜佳; 陈维佩

    2001-01-01

    幽门螺杆菌(Helicobacter pylori,H.pylori)是消化道的主要致病因素之一,随着对H.pylori认识的深入,人们发现H.pylori的两个标志性毒素--细胞毒素相关蛋白(cytotoxin-associated protein,cagA)和空泡毒素(vacuolating cytotoxin,VacA)不仅关系紧密,而且在致病过程中扮演了重要角色.本文主要阐述CagA和VacA的致病机制和它们的临床意义.

  10. Observation of sperm-head vacuoles and sperm morphology under light microscope.

    Science.gov (United States)

    Park, Yong-Seog; Park, Sol; Ko, Duck Sung; Park, Dong Wook; Seo, Ju Tae; Yang, Kwang Moon

    2014-09-01

    The presence of sperm-head vacuoles has been suspected to be deleterious to the outcomes of assisted reproductive technology (ART). It is difficult to accurately distinguish morphologically abnormal sperm with vacuoles under a light microscope. This study was performed to analyze the result of the observation of sperm-head vacuoles using Papanicolaou staining under a light microscope and whether the male partner's age affects these vacuoles. Sperm morphology with vacuoles was evaluated using Papanicolaou staining and observed under a light microscope (400×) in 980 men. The normal morphology was divided into three categories (group A, 14% of normal morphology). The criteria for the sperm-head vacuoles were those given in the World Health Organization manual. For the analysis of the age factor, the participants were divided into the following groups: 26-30 years, 31-35 years, 36-40 years, 41-45 years, and 46-50 years. The percentage of sperm-head vacuoles increased with normal sperm morphology (group A vs. groups B, C) (p<0.05). In the case of the age factor, a statistically significant difference was not observed across any of the age groups. A majority of the sperm-head vacuoles showed a statistically significant difference among normal morphology groups. Therefore, we should consider the probability of the percentage of sperm-head vacuoles not increasing with age but with abnormal sperm morphology. A further study is required to clarify the effect of the sperm-head vacuoles on ART outcomes.

  11. Ghrelin and Helicobacter pylori infection

    Institute of Scientific and Technical Information of China (English)

    Hiroyuki Osawa

    2008-01-01

    Ghrelin is primarily secreted from the stomach and has been implicated in the coordination of eating behavior and weight regulation. Ghrelin also plays an essential role in the mechanism of gastric mucosal defense. Thus, it is important to clarify which diseases primar-ily influence changes in plasma ghrelin concentrations. Helicobacter pylori(H pylori infection is involved in the pathogenesis of gastritis, gastric and duodenal ulcer, gastric carcinoma, and mucosa-associated lym-phoid tissue lymphorna. H pylori eradication is related to body weight change. Compared, H pylori infected and negative subjects with normal body mass index, plasma ghrelin concentration, gastric ghrelin mRNA, and the number of ghrelin producing cells in gastric mucosa are significantly lower in Hpylori injected sub-jects than in H pylori-negative controls. Plasma ghrelin concentration decreases with the progression of gastric atrophy. Impaired gastric ghrelin production in associa-tion with atrophic gastritis induced by Hpylori infection accounts for the decrease in plasma ghrelin concentra-tion. However, the ratio of plasma acylated ghrelin to total ghrelin levels is higher in patients with chronic atrophic gastritis than in healthy subjects. This may re-sult from the compensatory increase in plasma active ghrelin concentration in response to gastric atrophy. After H pylori eradication, gastric preproghrelin mRNA expression is increased nearly 4-fold in most cases. However, changes in plasma ghrelin concentrations be-fore and after H pylori cure are not associated with the gastric ghrelin production. Plasma ghrelin changes are inversely correlated with both body weight change and initial plasma ghrelin levels.

  12. Redox Enzymes of Red Beetroot Vacuoles (Beta vulgaris L.

    Directory of Open Access Journals (Sweden)

    E.V. Pradedova

    2014-12-01

    Full Text Available Years of research have shown that some of the redox elements (enzymes, coenzymes, and co-substrate are isolated from each other kinetic and spatial manner (compartmentalization in the eukaryotic cells. The redox elements forming the "highly" and "widely" specialized redox system are found in all cell structures: mitochondria, plastids, peroxisomes, apoplast, nucleus etc. In recent years the active involvement of the central vacuole in the maintenance of the plant cell redox homeostasis is discussed, actually the information about the vacuolar redox system is very small. The high-priority redox processes and "redox-specialization" of the vacuolar compartment are not known. We have begun a study of red beet-root vacuole redox systems (Beta vulgaris L. and have identified redox enzymes such as: phenol peroxidase (EC 1.11.1.7, superoxide dismutase (EC 1.15.1.1 and glutathione reductase (EC 1.8.1.7. This paper presents some of the characteristics of these enzymes and considers the probable ways of their functioning in vacuolar redox chains.

  13. Enzymic and protein character of tonoplast from Hippeastrum vacuoles

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.J.

    1981-01-01

    The membrane of anthocyanin containing Hippeastrum petal vacuoles was examined for protein and enzyme content after purification by equilibrium density centrifugation. Light scattering, protein, and a Mg/sup 2 +/ -dependent nucleotide specific ATPase were associated with membrane having a density of 1.08 to 1.12 grams per cubic centimeter. A small amount of acid phosphatase was also present in this region of the gradient, but this activity peaked at about 1.12 grams per cubic centimeter. A component of yeast tonoplast, ..cap alpha..-mannosidase, was not significantly present. UDP-glucose, anthocyanidin-3-O-glucosyltransferase, thought to be a cytosol enzyme in Hippeastrum, was absent from tonoplast of vacuoles isolated by osmotic shock in 0.2 molar K/sub 2/HPO/sub 4/ or 0.35 molar mannitol. Vacuolar acid phosphatase was insensitive to ethylenediaminetetraacetate but was 80% inhibited by 10 millimolar KF, while ATPase was inactivated by 2 millimolar ethylenediaminetetraacetate and only 50% inhibited by 10 millimolar KF,. Five major and about 9 minor polypeptides were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane protein on 5 to 30 and 6 to 16% gradient gels.

  14. Purification and proteomics of pathogen-modified vacuoles and membranes

    Directory of Open Access Journals (Sweden)

    Jo-Ana eHerweg

    2015-06-01

    Full Text Available Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e. the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.

  15. Mitochondrial Extrusion through the cytoplasmic vacuoles during cell death.

    Science.gov (United States)

    Nakajima, Akihito; Kurihara, Hidetake; Yagita, Hideo; Okumura, Ko; Nakano, Hiroyasu

    2008-08-29

    Under various conditions, noxious stimuli damage mitochondria, resulting in mitochondrial fragmentation; however, the mechanisms by which fragmented mitochondria are eliminated from the cells remain largely unknown. Here we show that cytoplasmic vacuoles originating from the plasma membrane engulfed fragmented mitochondria and subsequently extruded them into the extracellular spaces in undergoing acute tumor necrosis factor alpha-induced cell death in a caspase-dependent fashion. Notably, upon fusion of the membrane encapsulating mitochondria to the plasma membrane, naked mitochondria were released into the extracellular spaces in an exocytotic manner. Mitochondrial extrusion was specific to tumor necrosis factor alpha-induced cell death, because a genotoxic stress-inducing agent such as cisplatin did not elicit mitochondrial extrusion. Moreover, intact actin and tubulin cytoskeletons were required for mitochondrial extrusion as well as membrane blebbing. Furthermore, fragmented mitochondria were engulfed by cytoplasmic vacuoles and extruded from hepatocytes of mice injected with anti-Fas antibody, suggesting that mitochondrial extrusion can be observed in vivo under pathological conditions. Mitochondria are eliminated during erythrocyte maturation under physiological conditions, and anti-mitochondrial antibody is detected in some autoimmune diseases. Thus, elucidating the mechanism underlying mitochondrial extrusion will open a novel avenue leading to better understanding of various diseases caused by mitochondrial malfunction as well as mitochondrial biology.

  16. The role of Plasmodium falciparum food vacuole plasmepsins.

    Science.gov (United States)

    Liu, Jun; Gluzman, Ilya Y; Drew, Mark E; Goldberg, Daniel E

    2005-01-14

    Plasmepsins (PMs) are thought to have an important function in hemoglobin degradation in the malarial parasite Plasmodium falciparum and have generated interest as antimalarial drug targets. Four paralogous plasmepsins reside in the food vacuole of P. falciparum. Targeted gene disruption by double crossover homologous recombination has been employed to study food vacuole plasmepsin function in cultured parasites. Parasite clones with deletions in each of the individual PM I, PM II, and HAP genes as well as clones with a double PM IV/PM I disruption have been generated. All of these clones lack the corresponding PMs, are viable, and appear morphologically normal. PM II and PM IV/I disruptions have longer doubling times than the 3D7 parental line in rich RPMI medium. This appears to be because of a decreased level of productive progeny rather than an increased cell cycle time. In amino acid-limited medium, all four knockouts exhibit slower growth than the parental strain. Compared with 3D7, knock-out clone sensitivity to aspartic and cysteine protease inhibitors is changed minimally. These results suggest substantial functional redundancy and have important implications for the design of antimalarial drugs. The slow growth phenotype may explain why P. falciparum has maintained four plasmepsin genes with overlapping functions.

  17. Epidemiology of Helicobacter pylori infection.

    Science.gov (United States)

    Leja, Mārcis; Axon, Anthony; Brenner, Hermann

    2016-09-01

    This review of recent publications related to the epidemiology of Helicobacter pylori highlights the origin of the infection, its changing prevalence, transmission, and outcome. A number of studies have addressed the ancestor roots of the bacteria, and the first genomewide analysis of bacterial strains suggests that its coexistence with humans is more ancient than previously thought. As opposed to the generally declining prevalence of H. pylori (including China and Japan), in Sweden, the prevalence of atrophic gastritis in the young population has risen. The prevalence of the infection remains high in the indigenous populations of the Arctic regions, and reinfection rates are high. A high prevalence is permanently found in the Siberian regions of Russia as well. Several studies, some of which used multiplex serology, addressed prevalence of and risks associated with various H. pylori serotypes, thereby enabling more precise risk assessment. Transmission of H. pylori was discussed, specifically fecal-oral transmission and the use of well-water and other unpurified water. Finally, the long-term course of H. pylori infection was considered, with an estimated 89% of noncardia gastric cancer cases being attributable to the infection. © 2016 John Wiley & Sons Ltd.

  18. Comprehensive mapping of the Helicobacter pylori NikR regulon provides new insights in bacterial nickel responses

    Science.gov (United States)

    Vannini, Andrea; Pinatel, Eva; Costantini, Paolo Emidio; Pelliciari, Simone; Roncarati, Davide; Puccio, Simone; De Bellis, Gianluca; Peano, Clelia; Danielli, Alberto

    2017-01-01

    Nickel homeostasis is important for pathogenic and ureolytic bacteria, which use this metal ion as enzymatic cofactor. For example, in the human pathogen Helicobacter pylori an optimal balance between nickel uptake and incorporation in metallo-enzymes is fundamental for colonization of the host. Nickel is also used as cofactor to modulate DNA binding of the NikR regulator, which controls transcription of genes involved in nickel trafficking or infection in many bacteria. Accordingly, there is much interest in a systematic characterization of NikR regulation. Herein we use H. pylori as a model to integrate RNA-seq and ChIP-seq data demonstrating that NikR not only regulates metal-ion transporters but also virulence factors, non-coding RNAs, as well as toxin-antitoxin systems in response to nickel stimulation. Altogether, results provide new insights into the pathobiology of H. pylori and contribute to understand the responses to nickel in other bacteria. PMID:28393877

  19. Reactive oxygen species (ROS) is not a promotor of taxol-induced cytoplasmic vacuolization

    Science.gov (United States)

    Sun, Qingrui; Chen, Tongsheng

    2009-02-01

    we have previously reported that taxol, a potent anticancer agent, induces caspase-independent cell death and cytoplasmic vacuolization in human lung adenocarcinoma (ASTC-a-1) cells. However, the mechanisms of taxol-induced cytoplasmic vacuolization are poorly understood. Reactive oxygen species (ROS) has been reported to be involved in the taxol-induced cell death. Here, we employed confocal fluorescence microscopy imaging to explore the role of ROS in taxol-induced cytoplasmic vacuolization. We found that ROS inhibition by addition of N-acetycysteine (NAC), a total ROS scavenger, did not suppress these vacuolization but instead increased vacuolization. Take together, our results showed that ROS is not a promotor of the taxol-induced cytoplasmic vacuolization.

  20. Simplification of vacuole structure during plant cell death triggered by culture filtrates of Erwinia carotovora

    Institute of Scientific and Technical Information of China (English)

    Yumi Hirakawa; Toshihisa Nomura; Seiichiro Hasezawa; Takumi Higaki

    2015-01-01

    Vacuoles are suggested to play crucial roles in plant defense-related cel death. During programmed cel death, previous live cel imaging studies have observed vacuoles to become simpler in structure and have implicated this simplification as a prelude to the vacuole’s rupture and consequent lysis of the plasma membrane. Here, we examined dynamics of the vacuole in cel cycle-synchronized tobacco BY-2 (Nicotiana tabacum L. cv. Bright Yel ow 2) cel s during cel death induced by application of culture filtrates of Erwinia carotovora. The filtrate induced death in about 90%of the cel s by 24 h. Prior to cel death, vacuole shape simplified and endoplasmic actin filaments disassembled;however, the vacuoles did not rupture until after plasma membrane integrity was lost. Instead of facilitating rupture, the simplification of vacuole structure might play a role in the retrieval of membrane components needed for defense-related cel death.

  1. Helicobacter pylori infection and skin disorders.

    Science.gov (United States)

    Kutlubay, Zekayi; Zara, Tuba; Engin, Burhan; Serdaroğlu, Server; Tüzün, Yalçin; Yilmaz, Erkan; Eren, Bülent

    2014-08-01

    Helicobacter pylori is a Gram-negative bacterium that has been linked to peptic ulcer disease, gastric lymphoma, and gastric carcinoma. Apart from its well-demonstrated role in gastroduodenal diseases, some authors have suggested a potential role of Helicobacter pylori infection in several extra-intestinal pathologies including haematological, cardiovascular, neurological, metabolic, autoimmune, and dermatological diseases. Some studies suggest an association between Helicobacter pylori infection and skin diseases such as chronic idiopathic urticaria and rosacea. There have also been few case reports documenting association between Helicobacter pylori and psoriasis vulgaris, Behçet's disease, alopecia areata, Henoch-Schönlein purpura, and Sweet's syndrome. However, more systematic studies are required to clarify the proposed association between Helicobacter pylori and skin diseases; most of the studies do not show relevant relationships of these diseases with Helicobacter pylori infections. This review discusses skin diseases that are believed to be associated with Helicobacter pylori.

  2. Bioterrorism: toxins as weapons.

    Science.gov (United States)

    Anderson, Peter D

    2012-04-01

    The potential for biological weapons to be used in terrorism is a real possibility. Biological weapons include infectious agents and toxins. Toxins are poisons produced by living organisms. Toxins relevant to bioterrorism include ricin, botulinum, Clostridium perfrigens epsilson toxin, conotoxins, shigatoxins, saxitoxins, tetrodotoxins, mycotoxins, and nicotine. Toxins have properties of biological and chemical weapons. Unlike pathogens, toxins do not produce an infection. Ricin causes multiorgan toxicity by blocking protein synthesis. Botulinum blocks acetylcholine in the peripheral nervous system leading to muscle paralysis. Epsilon toxin damages cell membranes. Conotoxins block potassium and sodium channels in neurons. Shigatoxins inhibit protein synthesis and induce apoptosis. Saxitoxin and tetrodotoxin inhibit sodium channels in neurons. Mycotoxins include aflatoxins and trichothecenes. Aflatoxins are carcinogens. Trichothecenes inhibit protein and nucleic acid synthesis. Nicotine produces numerous nicotinic effects in the nervous system.

  3. Bacterial toxins as immunomodulators.

    Science.gov (United States)

    Donaldson, David S; Williams, Neil A

    2009-01-01

    Bacterial toxins are the causative agent at pathology in a variety of diseases. Although not always the primary target of these toxins, many have been shown to have potent immunomodulatory effects, for example, inducing immune responses to co-administered antigens and suppressing activation of immune cells. These abilities of bacterial toxins can be harnessed and used in a therapeutic manner, such as in vaccination or the treatment of autoimmune diseases. Furthermore, the ability of toxins to gain entry to cells can be used in novel bacterial toxin based immuno-therapies in order to deliver antigens into MHC Class I processing pathways. Whether the immunomodulatory properties of these toxins arose in order to enhance bacterial survival within hosts, to aid spread within the population or is pure serendipity, it is interesting to think that these same toxins potentially hold the key to preventing or treating human disease.

  4. Structural, functional and mutational analysis of the pfr gene encoding a ferritin from Helicobacter pylori.

    Science.gov (United States)

    Bereswill, S; Waidner, U; Odenbreit, S; Lichte, F; Fassbinder, F; Bode, G; Kist, M

    1998-09-01

    The function of the pfr gene encoding the ferritin from Helicobacter pylori was investigated using the Fur titration assay (FURTA) in Escherichia coli, and by characterization of a pfr-deficient mutant strain of H. pylori. Nucleotide sequence analysis revealed that the pfr region is conserved among strains (> 95% nucleotide identity). Two transcriptional start sites, at least one of them preceded by a sigma 70-dependent promoter, were identified. Provision of the H. pylori pfr gene on a multicopy plasmid resulted in reversal of the Fur-mediated repression of the fhuF gene in E. coli, thus enabling the use of the FURTA for cloning of the ferritin gene. Inactivation of the pfr gene, either by insertion of a resistance cassette or by deletion of the up- and downstream segments, abolished this function. Immunoblot analysis with a Pfr-specific antiserum detected the Pfr protein in H. pylori and in E. coli carrying the pfr gene on a plasmid. Pfr-deficient mutants of H. pylori were generated by marker-exchange mutagenesis. These were more susceptible than the parental strain to killing by various metal ions including irons, copper and manganese, whereas conditions of oxidative stress or iron deprivation were not discriminative. Analysis by element-specific electron microscopy revealed that growth of H. pylori in the presence of iron induces the formation of two kinds of cytoplasmic aggregates: large vacuole-like bodies and smaller granules containing iron in association with oxygen or phosphorus. Neither of these structures was detected in the pfr-deficient mutant strain. Furthermore, the ferritin accumulated under iron overload and the pfr-deficient mutant strains lacked expression of a 12 kDa protein which was negatively regulated by iron in the parental strain. The results indicate that the nonhaem-iron ferritin is involved in the formation of iron-containing subcellular structures and contributes to metal resistance of H. pylori. Further evidence for an interaction of

  5. Downregulated regulatory T cell function is associated with increased peptic ulcer in Helicobacter pylori-infection.

    Science.gov (United States)

    Bagheri, Nader; Shirzad, Hedayatollah; Elahi, Shokrollah; Azadegan-Dehkordi, Fatemeh; Rahimian, Ghorbanali; Shafigh, Mohammedhadi; Rashidii, Reza; Sarafnejad, Abdulfatah; Rafieian-Kopaei, Mahmoud; Faridani, Rana; Tahmasbi, Kamran; Kheiri, Soleiman; Razavi, Alireza

    2017-09-01

    Helicobacter pylori (H. pylori) chronically colonizes gastric/duodenal mucosa and induces gastroduodenal disease such as gastritis and peptic ulcer and induces vigorous innate and specific immune responses; however, the infection is not removed, a state of chronic active gastritis persists for life if untreated. The objective of this study was to determine the number of regulatory T cells (Tregs) in gastric mucosa of patients with gastritis and peptic ulcer and determined the relationship between main virulence factor of H. pylori and Tregs. A total of 89 patients with gastritis, 63 patients with peptic ulcer and 40 healthy, H. pylori-negative subjects were enrolled in this study. Expression of CD4 and Foxp3 was determined by immunohistochemistry. Antrum biopsy was obtained for detection of H. pylori, bacterial virulence factors and histopathological assessments. TGF-β1, IL-10 and FOXP3 expressions were determined by real-time polymerase chain reaction (qPCR). The numbers of CD4(+) and Foxp3(+) T cells as well as the expression of IL-10, TGF-β1, FOXP3, INF-γ and IL-17A in infected patients were significantly higher than the ones in uninfected patients. Also, the number of CD4(+) T cells was independent on the vacuolating cytotoxin A (vacA) and outer inflammatory protein A (oipA), but it was positively correlated with cytotoxin-associated gene A (cagA). Instead, the number of Foxp3(+) T cells was dependent on the vacA and oipA, but it was independent on cagA. The number of Foxp3(+) T cells and the expression of IL-10, TGF-β1 and FOXP3 in infected patients with gastritis were significantly higher than the ones in infected patients with peptic ulcer. Moreover, the number of CD4(+) T cells and the expression of IL-17A and INF-γ was the lowest in the gastritis patients, however, increased progressively in the peptic ulcer patients. Additionally, the numbers of CD4(+) and Foxp3(+) T cells as well as the expression of IL-10, TGF-β1, FOXP3 and INF-γ were

  6. Immunofluorescent localization of ubiquitin and proteasomes in nucleolar vacuoles of soybean root meristematic cells

    OpenAIRE

    Stępiński, D.

    2012-01-01

    In this study, using the immunofluorescent method, the immunopositive signals to ubiquitin and proteasomes in nucleoli of root meristematic cells of soybean seedlings have been observed. In fact, those signals were present exclusively in nucleolar vacuoles. No signals were observed in the nucleolar territory out of the nucleolar vacuoles or in the nucleoli without vacuoles. The ubiquitin-proteasome system (UPS) may act within the nucleoli of plants with high metabolic activities and may provi...

  7. Co-occurrence of tannin and tannin-less vacuoles in sensitive plants.

    Science.gov (United States)

    Fleurat-Lessard, Pierrette; Béré, Emile; Lallemand, Magali; Dédaldéchamp, Fabienne; Roblin, Gabriel

    2016-05-01

    Vacuoles of different types frequently coexist in the same plant cell, but the duality of the tannin/tannin-less vacuoles observed in Mimosa pudica L. is rare. In this plant, which is characterized by highly motile leaves, the development and original features of the double vacuolar compartment were detailed in primary pulvini from the young to the mature leaf stage. In young pulvini, the differentiation of tannin vacuoles first occurred in the epidermis and progressively spread toward the inner cortex. In motor cells of nonmotile pulvini, tannin deposits first lined the membranes of small vacuole profiles and then formed opaque clusters that joined together to form a large tannin vacuole (TV), the proportion of which in the cell was approximately 45%. At this stage, transparent vacuole profiles were rare and small, but as the parenchyma cells enlarged, these profiles coalesced to form a transparent vacuole with a convexity toward the larger-sized tannin vacuole. When leaf motility began to occur, the two vacuole types reached the same relative proportion (approximately 30%). Finally, in mature cells displaying maximum motility, the large transparent colloidal vacuole (CV) showed a relative proportion increasing to approximately 50%. At this stage, the proportion of the tannin vacuole, occurring in the vicinity of the nucleus, decreased to approximately 10%. The presence of the condensed type of tannins (proanthocyanidins) was proven by detecting their fluorescence under UV light and by specific chemical staining. This dual vacuolar profile was also observed in nonmotile parts of M. pudica (e.g., the petiole and the stem). Additional observations of leaflet pulvini showing more or less rapid movements showed that this double vacuolar structure was present in certain plants (Mimosa spegazzinii and Desmodium gyrans), but absent in others (Albizzia julibrissin, Biophytum sensitivum, and Cassia fasciculata). Taken together, these observations strongly suggest that a

  8. Helicobacter pylori promotes the expression of Kruppel-like factor 5, a mediator of carcinogenesis, in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Jennifer M Noto

    Full Text Available Helicobacter pylori is the strongest known risk factor for the development of gastric adenocarcinoma. H. pylori expresses a repertoire of virulence factors that increase gastric cancer risk, including the cag pathogenicity island and the vacuolating cytotoxin (VacA. One host element that promotes carcinogenesis within the gastrointestinal tract is Krüppel-like factor 5 (KLF5, a transcription factor that mediates key cellular functions. To define the role of KLF5 within the context of H. pylori-induced inflammation and injury, human gastric epithelial cells were co-cultured with the wild-type cag(+ H. pylori strain 60190. KLF5 expression was significantly upregulated following co-culture with H. pylori, but increased expression was independent of the cag island or VacA. To translate these findings into an in vivo model, C57BL/6 mice were challenged with the wild-type rodent-adapted cag(+ H. pylori strain PMSS1 or a PMSS1 cagE(- isogenic mutant. Similar to findings in vitro, KLF5 staining was significantly enhanced in gastric epithelium of H. pylori-infected compared to uninfected mice and this was independent of the cag island. Flow cytometry revealed that the majority of KLF5(+ cells also stained positively for the stem cell marker, Lrig1, and KLF5(+/Lrig1(+ cells were significantly increased in H. pylori-infected versus uninfected tissue. To extend these results into the natural niche of this pathogen, levels of KLF5 expression were assessed in human gastric biopsies isolated from patients with or without premalignant lesions. Levels of KLF5 expression increased in parallel with advancing stages of neoplastic progression, being significantly elevated in gastritis, intestinal metaplasia, and dysplasia compared to normal gastric tissue. These results indicate that H. pylori induces expression of KLF5 in gastric epithelial cells in vitro and in vivo, and that the degree of KLF5 expression parallels the severity of premalignant lesions in human

  9. Comparison of the virulence markers of helicobacter pylori and their associated diseases in patients from Pakistan and Afghanistan

    Directory of Open Access Journals (Sweden)

    Javed Yakoob

    2013-01-01

    Full Text Available Background/Aim: Helicobacter pylori is a Gram-negative bacteria, which is associated with development of gastroduodenal diseases. The prevalence of H. pylori and the virulence markers cytotoxin-associated gene A and E (cagA, cagE and vacuolating-associated cytotoxin gene (vacA alleles varies in different parts of the world. H. pylori virulence markers cagA, cagE, and vacA alleles in local and Afghan nationals with H. pylori-associated gastroduodenal diseases were studied. Patients and Methods: Two hundred and ten patients with upper gastrointestinal symptoms and positive for H. pylori by the urease test and histology were included. One hundred and nineteen were local nationals and 91 were Afghans. The cagA, cagE, and vacA allelic status was determined by polymerase chain reaction. Results: The nonulcer dyspepsia (NUD was common in the Afghan patients (P = 0.025. In Afghan H. pylori strains, cagA was positive in 14 (82% with gastric carcinoma (GC compared with 29 (45% with NUD (P = 0.006, whereas cagE was positive in 11 (65% with GC and 4 (67% with duodenal ulcer (DU compared with 12 (18% with NUD (P < 0.001 and 0.021, respectively. The vacA s1a/b1was positive in 10 (59% of GC compared with 20 (31% in NUD (P = 0.033. In Pakistani strains, cagE was positive in 12 (60% with GC, 7 (58% with GU, 12 (60% with DU compared with 11 (16% with NUD (P < 0.001, 0.004, and < 0.001, respectively. In Pakistani strains, cagA/s1a/m1 was 39 (33% compared with Afghans in 17 (19% (P = 0.022. Moderate to severe mucosal inflammation was present in 51 (43% Pakistani patients compared with 26 (28% (P = 0.033 in Afghans. It was also associated with grade 1 lymphoid aggregate development in Pakistani patients 67 (56% compared with 36 (40% (P = 0.016 in Afghans. Conclusion: Distribution of H. pylori virulence marker cagE with DU was similar in Afghan and Pakistan H. pylori strains. Chronic active inflammation was significantly associated with Pakistani H. pylori strains.

  10. Helicobacter pylori outer membrane vesicles inhibit human T cell responses via induction of monocyte COX-2 expression.

    Science.gov (United States)

    Hock, Barry D; McKenzie, Judith L; Keenan, Jacqueline I

    2017-06-01

    The modulation of T cell responses by Helicobacter pylori is thought to potentiate both H. pylori persistence and development of gastric pathologies including cancer. Release of outer membrane vesicles (OMV) by H. pylori provides a potential vehicle for modulation of the immune system. Although OMV are thought to have T cell suppressive activity, this has not yet been demonstrated. Their suppressive activity was investigated in this study using the responses of peripheral blood mononuclear cells (PBMC) to T cell stimuli as a readout. We demonstrate that addition of OMV to PBMC significantly inhibits subsequent T cell proliferation in a cyclo-oxygenase-2 (COX-2)-dependent manner. Addition of OMV did not significantly modulate PBMC apoptosis, but induced strong expression of COX-2 by the monocytes present and significantly increased levels of PGE2 and IL-10. These effects were independent of vacuolating cytotoxin expression. Together, these findings demonstrate that OMV can suppress human T cell responses and that the predominant mechanism is not through a direct effect on the T cells but results from the induction of COX-2 expression in monocytes. This increased COX-2 activity may modulate not only H. pylori-directed immune responses but also wider immune responses. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Bacterial toxins: friends or foes?

    OpenAIRE

    Schmitt, C K; Meysick, K. C.; O'Brien, A D

    1999-01-01

    Many emerging and reemerging bacterial pathogens synthesize toxins that serve as primary virulence factors. We highlight seven bacterial toxins produced by well-established or newly emergent pathogenic microbes. These toxins, which affect eukaryotic cells by a variety of means, include Staphylococcus aureus alpha-toxin, Shiga toxin, cytotoxic necrotizing factor type 1, Escherichia coli heat-stable toxin, botulinum and tetanus neurotoxins, and S. aureus toxic-shock syndrome toxin. For each, we...

  12. DRUG RESISTANCE IN HELICOBACTER PYLORI

    Directory of Open Access Journals (Sweden)

    Júlia Silveira VIANNA

    Full Text Available ABSTRACT Background Helicobacter pylori has a worldwide distribution and is associated with the pathogenesis of various diseases of the digestive system. Treatment to eradicate this microorganism involves the use of a combination of antimicrobials, such as amoxicillin, metronidazole, clarithromycin, and levofloxacin, combined with proton pump inhibitors. Although the current therapy is effective, a high rate of treatment failure has been observed, mainly because of the acquisition of point mutations, one of the major resistance mechanisms developed by H. pylori. This phenomenon is related to frequent and/or inappropriate use of antibiotics. Conclusion This review reported an overview of the resistance to the main drugs used in the treatment of H. pylori, confirming the hypothesis that antibacterial resistance is a highly local phenomenon and genetic characteristics of a given population can influence which therapy is the most appropriate.

  13. Diagnosis of Helicobacter pylori Infection.

    Science.gov (United States)

    Tongtawee, Taweesak; Kaewpitoon, Soraya; Kaewpitoon, Natthawut; Dechsukhum, Chavaboon; Leeanansaksiri, Wilairat; Loyd, Ryan A; Matrakool, Likit; Panpimanmas, Sukij

    2016-01-01

    Helicobacter pylori infection plays an important role in the pathogenesis of chronic gastritis, peptic ulcer disease and gastric malignancy. A diagnosis of infection is thus an important part of a treatment strategy of many gastrointestinal tract diseases. Many diagnostic tests are available but all have some limitations in different clinical situations and laboratory settings. A single gold standard cannot available, but be used for diagnosis of Helicobacter pylori infection in daily clinical practice in all areas, so several techniques have been developed to give reliable results, especially focusing on real time endoscopic features. The narrow band imaging system (NBI) and high resolution endoscopy are imaging techniques for enhanced visualization of infected mucosa and premalignant gastric lesions. The aim of this article is to review the current diagnostic options and possible future developments detection of Helicobacter pylori infection.

  14. Pathogen vacuole purification from legionella-infected amoeba and macrophages.

    Science.gov (United States)

    Hoffmann, Christine; Finsel, Ivo; Hilbi, Hubert

    2013-01-01

    Legionella pneumophila replicates intracellularly in environmental and immune phagocytes within a unique membrane-bound compartment, the Legionella-containing vacuole (LCV). Formation of LCVs is strictly dependent on the Icm/Dot type IV secretion system and the translocation of "effector" proteins into the cell. Some effector proteins decorate the LCV membrane and subvert host cell vesicle trafficking pathways. Here we describe a method to purify intact LCVs from Dictyostelium discoideum amoebae and RAW 264.7 murine macrophages. The method comprises a two-step protocol: first, LCVs are enriched by immuno-magnetic separation using an antibody against a bacterial effector protein specifically localizing to the LCV membrane, and second, the LCVs are further purified by density gradient centrifugation. The purified LCVs can be characterized by proteomics and other biochemical approaches.

  15. The Cytoplasm-to-Vacuole Targeting Pathway: A Historical Perspective

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    Midori Umekawa

    2012-01-01

    Full Text Available From today's perspective, it is obvious that macroautophagy (hereafter autophagy is an important pathway that is connected to a range of developmental and physiological processes. This viewpoint, however, is relatively recent, coinciding with the molecular identification of autophagy-related (Atg components that function as the protein machinery that drives the dynamic membrane events of autophagy. It may be difficult, especially for scientists new to this area of research, to appreciate that the field of autophagy long existed as a “backwater” topic that attracted little interest or attention. Paralleling the development of the autophagy field was the identification and analysis of the cytoplasm-to-vacuole targeting (Cvt pathway, the only characterized biosynthetic route that utilizes the Atg proteins. Here, we relate some of the initial history, including some never-before-revealed facts, of the analysis of the Cvt pathway and the convergence of those studies with autophagy.

  16. Radiolabelling of cholera toxin

    Energy Technology Data Exchange (ETDEWEB)

    Santos, R.G.; Neves, Nicoli M.J. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Abdalla, L.F.; Brandao, R.L.; Etchehebehere, L. [Ouro Preto Univ., MG (Brazil). Escola de Farmacia. Lab. de Fisiologia e Bioquimica de Microorganismos; Lima, M.E. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Inst. de Ciencias Biologicas. Dept. de Bioquimica e Imunologia; Nicoli, J.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Inst. de Ciencias Biologicas. Dept. de Microbiologia

    1999-11-01

    Binding of cholera toxin to ganglioside receptors of enterocyte microvilli catalyzes the activation of adenylate cyclase causing a rise in cAMP which final result is a copious diarrhea. Saccharomyces boulardii, a nonpathogenic yeast has been used to prevent diarrhea. Although the antidiarrheic properties of S. boulardii are widely recognized, this yeast has been used on empirical basis, and the mechanism of this protective effect is unknown. The addition of cholera toxin to S. boulardii induces the raising of cAMP that triggers the activation of neutral trehalase. This suggests that toxin specifically binding to cells, is internalized and active the protein phosphorylation cascade. Our objective is labeling the cholera toxin to verify the presence of binding sites on yeast cell surfaces for the cholera toxin. Cholera toxin was radiolabelled with Na {sup 125} I by a chloramine-T method modified from Cuatrecasas and Griffiths et alii. The {sup 125} I-Cholera toxin showed a specific radioactivity at about 1000 cpm/fmol toxin. Biological activity of labeled cholera toxin measured by trehalase activation was similar to the native toxin. (author) 5 refs., 3 figs.; e-mail: nevesmj at urano.cdtn.br

  17. Interleukin-1 and TNF-α polymorphisms and Helicobacter pylori in a Brazilian Amazon population

    Institute of Scientific and Technical Information of China (English)

    Hivana Patricia Melo Barbosa; Luisa Caricio Martins; Sidney Emanuel Batista dos Santos; Samia Demachki; Monica Baraúna Assumpcao; Charliana Damasceno Aragao; Tereza Cristina de Oliveira Corvelo

    2009-01-01

    AIM:To study the association between Interleukin-1 (IL-1) and tumor necrosis factor (TNF)-α polymorphisms, infection by Helicobacter pylori ( H pylori) and the development of gastrointestinal diseases. METHODS:Genomic DNA was ext racted f rom the peripheral blood of 177 patients with various gastrointestinal diseases and from 100 healthy volunteers. The polymorphisms in IL-1β and TNF-α genes were analyzed using the polymerase chain reactionrestriction fragment length polymorphism method PCRRFLP) and those from IL-1RN with PCR. The presence of infection due to H pylori and the presence of the CagA toxin were detected by serology. The histopathological parameters in the gastric biopsies of the patients were according to the Sydney classification. RESULTS:A comparison of the frequencies of the different polymorphisms studied among the patients and the control group demonstrated that the allele IL- 1RN*2 was more frequent among patients with gastric ulcers and adenocarcinoma. Carriers of the allele ILRN* 2 and those with reactive serology for anti-CagA IgG had a greater risk of developing peptic ulcer and gastric adenocarcinoma, as well as a higher degree of inflammation and neutrophilic activity in the gastric mucosa. CONCLUSION:Our results indicate a positive association between IL-1RN gene polymorphism and infection by positive H pylori CagA strains and the development of gastric ulcers and adenocarcinoma.

  18. Dispepsia ed Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Giovanni Fornaciari

    2003-09-01

    Full Text Available The effect of Helicobacter pylori (HP eradication on functional dyspepsia has been analysed in several clinical trials, including large, controlled and well-designed studies as well as small, flowed studies. The results of these studies indicate that HP infection does not play a major role in the aetiology of this disease and that HP eradication improves dyspeptic symptoms in no more than 15% of patients as compared to placebo. From a practical point of view 15 patients need to be treated for one to benefit while, in duodenal ulcer, 1.4 patient need to be treated for one to benefit. It remains to be elucidated if HP eradication in functional dyspepsia is useful to reduce the risk of developing organic dyspepsia (namely peptic ulcer in functional dyspepsia. In uninvestigated dyspepsia the management of HP infection in primary care has been fully debated.Two therapeutics strategies have been proposed: test and scope and test and treat. The value of test and treat strategy over alternative strategies has been demonstrated in several decision analyses. HP test and scope increases costs in primary care without improving symptoms and saves only 15% of endoscopies.

  19. Mixed infection with cagA positive and cagA negative strains of Helicobacter pylori lowers disease burden in The Gambia.

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    Ousman Secka

    Full Text Available BACKGROUND: The prevalence of Helicobacter pylori including strains with putatively virulent genotypes is high, whereas the H. pylori-associated disease burden is low, in Africa compared to developed countries. In this study, we investigated the prevalence of virulence-related H. pylori genotypes and their association with gastroduodenal diseases in The Gambia. METHODS AND FINDINGS: DNA extracted from biopsies and H. pylori cultures from 169 subjects with abdominal pain, dyspepsia or other gastroduodenal diseases were tested by PCR for H. pylori. The H. pylori positive samples were further tested for the cagA oncogene and vacA toxin gene. One hundred and twenty one subjects (71.6% were H. pylori positive. The cagA gene and more toxigenic s1 and m1 alleles of the vacA gene were found in 61.2%, 76.9% and 45.5% respectively of Gambian patients harbouring H. pylori. There was a high prevalence of cagA positive strains in patients with overt gastric diseases than those with non-ulcerative dyspepsia (NUD (p = 0.05; however, mixed infection by cagA positive and cagA negative strains was more common in patients with NUD compared to patients with gastric disease (24.5% versus 0%; p = 0.002. CONCLUSION: This study shows that the prevalence of H. pylori is high in dyspeptic patients in The Gambia and that many strains are of the putatively more virulent cagA+, vacAs1 and vacAm1 genotypes. This study has also shown significantly lower disease burden in Gambians infected with a mixture of cag-positive and cag-negative strains, relative to those containing only cag-positive or only cag-negative strains, which suggests that harbouring both cag-positive and cag-negative strains is protective.

  20. Mixed Infection with cagA Positive and cagA Negative Strains of Helicobacter pylori Lowers Disease Burden in The Gambia

    Science.gov (United States)

    Secka, Ousman; Antonio, Martin; Berg, Douglas E.; Tapgun, Mary; Bottomley, Christian; Thomas, Vivat; Walton, Robert; Corrah, Tumani; Thomas, Julian E.; Adegbola, Richard A.

    2011-01-01

    Background The prevalence of Helicobacter pylori including strains with putatively virulent genotypes is high, whereas the H. pylori-associated disease burden is low, in Africa compared to developed countries. In this study, we investigated the prevalence of virulence-related H. pylori genotypes and their association with gastroduodenal diseases in The Gambia. Methods and Findings DNA extracted from biopsies and H. pylori cultures from 169 subjects with abdominal pain, dyspepsia or other gastroduodenal diseases were tested by PCR for H. pylori. The H. pylori positive samples were further tested for the cagA oncogene and vacA toxin gene. One hundred and twenty one subjects (71.6%) were H. pylori positive. The cagA gene and more toxigenic s1 and m1 alleles of the vacA gene were found in 61.2%, 76.9% and 45.5% respectively of Gambian patients harbouring H. pylori. There was a high prevalence of cagA positive strains in patients with overt gastric diseases than those with non-ulcerative dyspepsia (NUD) (p = 0.05); however, mixed infection by cagA positive and cagA negative strains was more common in patients with NUD compared to patients with gastric disease (24.5% versus 0%; p = 0.002). Conclusion This study shows that the prevalence of H. pylori is high in dyspeptic patients in The Gambia and that many strains are of the putatively more virulent cagA+, vacAs1 and vacAm1 genotypes. This study has also shown significantly lower disease burden in Gambians infected with a mixture of cag-positive and cag-negative strains, relative to those containing only cag-positive or only cag-negative strains, which suggests that harbouring both cag-positive and cag-negative strains is protective. PMID:22140492

  1. New insights into the tonoplast architecture of plant vacuoles and vacuolar dynamics during osmotic stress

    Directory of Open Access Journals (Sweden)

    Marty Francis

    2005-08-01

    Full Text Available Abstract Background The vegetative plant vacuole occupies >90% of the volume in mature plant cells. Vacuoles play fundamental roles in adjusting cellular homeostasis and allowing cell growth. The composition of the vacuole and the regulation of its volume depend on the coordinated activities of the transporters and channels localized in the membrane (named tonoplast surrounding the vacuole. While the tonoplast protein complexes are well studied, the tonoplast itself is less well described. To extend our knowledge of how the vacuole folds inside the plant cell, we present three-dimensional reconstructions of vacuoles from tobacco suspension cells expressing the tonoplast aquaporin fusion gene BobTIP26-1::gfp. Results 3-D reconstruction of the cell vacuole made possible an accurate analysis of large spanning folds of the vacuolar membrane under both normal and stressed conditions, and suggested interactions between surrounding plastids. Dynamic, high resolution 3-D pictures of the vacuole in tobacco suspension cells monitored under different growth conditions provide additional details about vacuolar architecture. The GFP-decorated vacuole is a single continuous compartment transected by tubular-like transvacuolar strands and large membrane surfaces. Cell culture under osmotic stress led to a complex vacuolar network with an increased tonoplast surface area. In-depth 3-D realistic inspections showed that the unity of the vacuole is maintained during acclimation to osmotic stress. Vacuolar unity exhibited during stress adaptation, coupled with the intimate associations of vacuoles with other organelles, suggests a physiological role for the vacuole in metabolism, and communication between the vacuole and organelles, respectively, in plant cells. Desiccation stress ensuing from PEG treatment generates "double" membrane structures closely linked to the tonoplast within the vacuole. These membrane structures may serve as membrane reservoirs for

  2. Toxins from Bacteria

    OpenAIRE

    Henkel, James S.; Baldwin, Michael R.; Barbieri, Joseph T.

    2010-01-01

    Bacterial toxins damage the host at the site of bacterial infection or distanced from the site of infections. Bacterial toxins can be single proteins or organized as oligomeric protein complexes and are organized with distinct AB structure-function properties. The A domain encodes a catalytic activity; ADP-ribosylation of host proteins is the earliest post-translational modification determine to be performed by bacterial toxin, and now include glucosylation and proteolysis among other s. Bact...

  3. [Intoxication of botulinum toxin].

    Science.gov (United States)

    Chudzicka, Aleksandra

    2015-09-01

    Botulinum toxin is an egzotoxin produced by Gram positive bacteria Clostridium botulinum. It is among the most potent toxins known. The 3 main clinical presentations of botulism are as follows: foodborne botulism, infant botulism and wound botulism. The main symptom of intoxication is flat muscles paralysis. The treatment is supportive care and administration of antitoxin. In prevention the correct preparing of canned food is most important. Botulinum toxin is accepted as a biological weapon.

  4. Dominant cagA/vacA genotypes and coinfection frequency of H. Pylori in peptic ulcer or chronic gastritis patients in Zhejiang Province and correlations among different genotypes, coinfection and severity of the diseases

    Institute of Scientific and Technical Information of China (English)

    CHEN Xue-jun; YAN Jie; SHEN Yue-fang

    2005-01-01

    Background Almost half of the world's population suffer from the Helicobacter pylori (H. Pylori) infection, but only some individuals develop gastric diseases with clinical symptoms. One reason for the phenomenon may be the different pathogenicity of infected H. Pylori strains. The presence of cytotoxin-associated gene A (cagA) and expression of vacuolating cytotoxin activity encoded by vacuolating cytotoxin gene A (vacA) are considered the two major virulent markers of H. Pylori. The aim of this study was to detect dominant cagA/vacA genotypes and coinfection frequency of H. Pylori in patients with peptic ulceration (PU) or chronic gastritis (CG), and to determine correlations among different cagA/vacA genotypes, coinfection and severity of the diseases. Methods For each of 139 patients in Zhejiang Province who had been diagnosed as PU or CG based on clinical symptoms and gastroscopy, two gastric biopsy specimens (one from antrum and the other from corpus) for H. Pylori isolation were taken by two different disinfected biopsy forceps. One hundred and fifty-six H. Pylori strains were isolated from both the antrum and corpus biopsy specimens of 78 patients (36 PU and 42 CG). PCRs were performed to detect cagA genes, and signal (s) and middle (m) regions of vacA genes in the H. Pylori isolates. The amplified fragments of dominant vacA gene s and m subtypes from representative H. Pylori isolates were sequenced after TA cloning. Dominant cagA/vacA genotypes of the H. Pylori isolates, coinfection frequency and correlations among the different genotypes, coinfection and severity of the diseases were determined.Results Of the H. Pylori strains isolated from the antrum specimens, 96.2% were cagA gene positive, as were 97.4% of the H. Pylori strains isolated from the corpus specimens. Only one s region subtype (s1a) and four m region subtypes m1, m2, m1b and m1b-m2 of vacA gene were found. The proportions of vacA gene subtypes s1a/m1, s1a/m2, s1a/m1b and s1a/m1b-m2 in the

  5. Helicobacter pylori and Peptic Ulcers

    Centers for Disease Control (CDC) Podcasts

    2010-08-17

    In this podcast, CDC's Dr. David Swerdlow discusses the relationship between Helicobacter pylori and peptic ulcer disease and trends in hospitalization rates for peptic ulcer disease in the United States between 1998 and 2005.  Created: 8/17/2010 by National Center for Emerging and Zoonotic Infectious Diseases.   Date Released: 8/17/2010.

  6. Chorea caused by toxins.

    Science.gov (United States)

    Miyasaki, Janis M

    2011-01-01

    Chorea is uncommonly caused by toxins. Anecdotal evidence from cases of toxin-induced chorea assists in our understanding of neurodegenerative diseases associated with chorea. Beginning in medieval Europe with ergotism and the "fire that twisted people," spanning to crack dancing in contemporary times and the coexistence of alcohol abuse with chorea, toxins may exert direct effects to enhance mesolimbic dopamine transmission or indirect effects through gamma-aminobutyric acid modulation. The following chapter will discuss toxins associated with chorea and the presumed pathophysiology underlying the movement disorders in these case series.

  7. Trypanosoma cruzi Differentiates and Multiplies within Chimeric Parasitophorous Vacuoles in Macrophages Coinfected with Leishmania amazonensis.

    Science.gov (United States)

    Pessoa, Carina Carraro; Ferreira, Éden Ramalho; Bayer-Santos, Ethel; Rabinovitch, Michel; Mortara, Renato Arruda; Real, Fernando

    2016-05-01

    The trypanosomatids Leishmania amazonensis and Trypanosoma cruzi are excellent models for the study of the cell biology of intracellular protozoan infections. After their uptake by mammalian cells, the parasitic protozoan flagellates L. amazonensis and T. cruzi lodge within acidified parasitophorous vacuoles (PVs). However, whereas L. amazonensis develops in spacious, phagolysosome-like PVs that may enclose numerous parasites, T. cruzi is transiently hosted within smaller vacuoles from which it soon escapes to the host cell cytosol. To investigate if parasite-specific vacuoles are required for the survival and differentiation of T. cruzi, we constructed chimeric vacuoles by infection of L. amazonensis amastigote-infected macrophages with T. cruzi epimastigotes (EPIs) or metacyclic trypomastigotes (MTs). These chimeric vacuoles, easily observed by microscopy, allowed the entry and fate of T. cruzi in L. amazonensis PVs to be dynamically recorded by multidimensional imaging of coinfected cells. We found that although T. cruzi EPIs remained motile and conserved their morphology in chimeric vacuoles, T. cruzi MTs differentiated into amastigote-like forms capable of multiplying. These results demonstrate that the large adaptive vacuoles of L. amazonensis are permissive to T. cruzi survival and differentiation and that noninfective EPIs are spared from destruction within the chimeric PVs. We conclude that T. cruzi differentiation can take place in Leishmania-containing vacuoles, suggesting this occurs prior to their escape into the host cell cytosol.

  8. Preparative Procedures Markedly Influence the Appearance and Structural Integrity of Protein Storage Vacuoles in Soybean Seeds

    Science.gov (United States)

    In legumes, vacuoles serve as the final depository for storage proteins. The protein storage vacuoles (PSVs) of soybean contain electron-transparent globoid regions in which phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate) is sequestered. Here, I report the effect of preparative procedures o...

  9. Helicobacter pylori and Gastrointestinal Malignancies.

    Science.gov (United States)

    Venerito, Marino; Vasapolli, Riccardo; Rokkas, Theodoros; Malfertheiner, Peter

    2015-09-01

    Helicobacter pylori infection is the principal trigger of gastric carcinogenesis and gastric cancer (GC) and remains the third leading cause of cancer-related death in both sexes worldwide. In a big Japanese study, the risk of developing GC in patients with peptic ulcer disease who received H. pylori eradication therapy and annual endoscopic surveillance for a mean of 9.9 years was significantly lower after successful eradication therapy compared to the group with persistent infection (0.21%/year and 0.45%/year, respectively, p = .049). According to a recent meta-analysis, H. pylori eradication is insufficient in GC risk reduction in subjects with advanced precancerous conditions (i.e., intestinal metaplasia and dysplasia). A microsimulation model suggested screening smokers over the age of 50 in the U.S. for serum pepsinogens. This would allow to detect advanced gastric atrophy with endoscopic follow-up of subjects testing positive as a cost-effective strategy to reduce GC mortality. In a Taiwanese study, the anti-H. pylori IgG-based test-and-treat program had lower incremental cost-effectiveness ratios than that with (13)C-urea breath test in both sexes to prevent GC whereas expected years of life lost for GC were higher and the incremental cost-effectiveness ratios of test-and-treat programs were more cost-effective in young adults (30-69 years old) than in elders (>70 years old). With respect to gastrointestinal malignancies other than GC, a meta-analysis confirmed the inverse association between H. pylori infection and esophageal adenocarcinoma. In a Finnish study, H. pylori seropositivity was associated with an increased risk of biliary tract cancers (multivariate adjusted OR 2.63; 95% CI: 1.08-6.37), another meta-analysis showed a slightly increased rate of pancreatic cancer in patients with CagA-negative strains (OR: 1.30; 95% CI: 1.02-1.65), whereas current data suggest that the association between H. pylori and colorectal neoplasms may be population

  10. Architecture of the Helicobacter pylori Cag-type IV secretion system.

    Science.gov (United States)

    Terradot, Laurent; Waksman, Gabriel

    2011-04-01

    Type IV secretion systems (T4SS) are macromolecular assemblies used by bacteria to transport material across their membranes. T4SS are generally composed of a set of twelve proteins (VirB1-11 and VirD4). This represents a dynamic machine powered by three ATPases. T4SS are widespread in pathogenic bacteria where they are often used to deliver effectors into host cells. For example, the human pathogen Helicobacter pylori encodes a T4SS, the Cag-T4SS, which mediates the injection of the toxin CagA. We review the progress made in the past decade in our understanding of T4SS architecture. We translate this new knowledge to derive an understanding of the structure of the H. pylori Cag system, and use recent protein-protein interaction data to refine this model. © 2011 The Authors Journal compilation © 2011 FEBS.

  11. H pylori are associated with chronic cholecystitis

    Institute of Scientific and Technical Information of China (English)

    Dong-Feng Chen; Lu Hu; Ping Yi; Wei-Wen Liu; Dian-Chun Fang; Hong Cao

    2007-01-01

    AIM:To study whether H pylori are associated with chronic cholecystitis.METHODS:The subjects were divided into three groups:H pylori-infected cholecystitis group,H pylorinegative cholecystitis group and control group.Pathologic changes of the gallbladder were observed by optic and electronic microscopes and the levels of interleukin-1,6 and 8(IL-1,6 and 8)were detected by radioimmunoassay.RESULTS:Histological evidence of chronic cholecystitis including degeneration,necrosis,inflammatory cell infiltration,were found in the region where H pylori-colonized.Levels of IL-1,6 and 8 in gallbladder mucosa homogenates were significantly higher in H pylori-infected cholecystitis group than those in H pylori-negative cholecystitis group and control group.CONCLUSION:H pylori infection may be related to cholecystitis.

  12. The nature of human sperm head vacuoles: a systematic literature review.

    Science.gov (United States)

    Boitrelle, Florence; Guthauser, Bruno; Alter, Laura; Bailly, Marc; Wainer, Robert; Vialard, François; Albert, Martine; Selva, Jacqueline

    2013-01-01

    Motile sperm organelle morphology examination (MSOME) involves the use of differential interference contrast microscopy (also called Nomarski contrast) at high magnification (at least 6300x) to improve the observation of live human spermatozoa. In fact, this technique evidences sperm head vacuoles that are not necessarily seen at lower magnifications - particularly if the vacuoles are small (i.e. occupying nature. In an attempt to clarify this debate, we performed a systematic literature review in accordance with the PRISMA guidelines. The PubMed database was searched from 2001 onwards with the terms "MSOME", "human sperm vacuoles", "high-magnification, sperm". Out of 180 search results, 21 relevant English-language publications on the nature of human sperm head vacuoles were finally selected and reviewed. Our review of the literature prompted us to conclude that sperm-head vacuoles are nuclear in nature and are related to chromatin condensation failure and (in some cases) sperm DNA damage.

  13. Early cytoplasmic vacuolization of African green monkey kidney cells by SV40.

    Science.gov (United States)

    Miyamura, T; Kitahara, T

    1975-01-01

    As early as 3--4 hours after infection with SV40 at a high input multiplicity, African green monkey (Cercopithecus aethiops) kidney (AGMK) cells developed cytoplasmic vacuolization. At 10--20 hours after infection, the vacuolization reached its maximal level, then disappeared and SV40 specific cytopathic change followed. This vacuolization developed before the synthesis of the specific T and V antigens. This early cytoplasmic vacuolization (ECV) was prevented by preincubating the virus with specific antiserum, or by heating the virus with MgCl2. The ECV could be induced by UV-irradiated SV40. Addition of metabolic inhibitors had no effect on the induction of the ECV. These results suggest that the capacity to induce the ECV resides in a structural component(s) of SV40 virion and the vacuolization is not associated with the replication of SV40.

  14. Early cytoplasmic vacuolization of African green monkey kidney cells by SV40. [uv radiation

    Energy Technology Data Exchange (ETDEWEB)

    Miyamura, T.; Kitahara, T.

    1975-01-01

    As early as 3 to 4 hours after infection with SV 40 at a high input multiplicity, African green monkey (Cercopithecus aethiops) kidney (AGMK) cells developed cytoplasmic vacuolization. At 10 to 20 hours after infection, the vacuolization reached its maximal level, then disappeared and SV 40 specific cytopathic change followed. This vacuolization developed before the synthesis of the specific T and V antigens. This early cytoplasmic vacuolization (ECV) was prevented by pre-incubating the virus with specific antiserum, or by heating the virus with MgCl/sub 2/. The ECV could be induced by uv-irradiated SV 40. Addition of metabolic inhibitors had no effect on the induction of the ECV. These results suggest that the capacity to induce the ECV resides in a structural component(s) of SV 40 virion and the vacuolization is not associated with the replication of SV 40.

  15. Motile tubular vacuoles in extramatrical mycelium and sheath hyphae of ectomycorrhizal systems.

    Science.gov (United States)

    Allaway, W G; Ashford, A E

    2001-01-01

    Extramatrical mycelium and outer hyphae of the sheath of Eucalyptus pilularis-Pisolithus tinctorius mycorrhizas contain abundant motile tubular vacuoles which accumulate the carboxyfluorescein analogue Oregon Green 488 carboxylic acid. The fluorochrome accumulates in a system of small vacuoles, tubules, and larger vacuoles, which are interlinked, motile, and pleiomorphic, in external hyphae, cords, and hyphae of the outer sheath. There is often a difference in fluorescence between two neighbouring cells, indicating that the dolipore septum exercises control on the movement of material between cells. Generally the motile tubular vacuole system in mycorrhizas resembles that previously found in isolated mycelium. The majority of fungal cells in the sheath contain no fluorochrome even after long exposure of the mycorrhiza to the solution, but with differential interference optics the cells are clearly seen to be alive and to contain vacuoles resembling those in the outer hyphae. In translocation experiments, long-distance transport of the fluorochrome is slow and slight, or even nonexistent in some cases.

  16. Oral Immunization with a Multivalent Epitope-Based Vaccine, Based on NAP, Urease, HSP60, and HpaA, Provides Therapeutic Effect on H. pylori Infection in Mongolian gerbils.

    Science.gov (United States)

    Guo, Le; Yang, Hua; Tang, Feng; Yin, Runting; Liu, Hongpeng; Gong, Xiaojuan; Wei, Jun; Zhang, Ying; Xu, Guangxian; Liu, Kunmei

    2017-01-01

    Epitope-based vaccine is a promising strategy for therapeutic vaccination against Helicobacter pylori (H. pylori) infection. A multivalent subunit vaccine containing various antigens from H. pylori is superior to a univalent subunit vaccine. However, whether a multivalent epitope-based vaccine is superior to a univalent epitope-based vaccine in therapeutic vaccination against H. pylori, remains unclear. In this study, a multivalent epitope-based vaccine named CWAE against H. pylori urease, neutrophil-activating protein (NAP), heat shock protein 60 (HSP60) and H. pylori adhesin A (HpaA) was constructed based on mucosal adjuvant cholera toxin B subunit (CTB), Th1-type adjuvant NAP, multiple copies of selected B and Th cell epitopes (UreA27-53, UreA183-203, HpaA132-141, and HSP60189-203), and also the epitope-rich regions of urease B subunit (UreB158-251 and UreB321-385) predicted by bioinformatics. Immunological properties of CWAE vaccine were characterized in BALB/c mice model. Its therapeutic effect was evaluated in H. pylori-infected Mongolian gerbil model by comparing with a univalent epitope-based vaccine CTB-UE against H. pylori urease that was constructed in our previous studies. Both CWAE and CTB-UE could induce similar levels of specific antibodies against H. pylori urease, and had similar inhibition effect of H. pylori urease activity. However, only CWAE could induce high levels of specific antibodies to NAP, HSP60, HpaA, and also the synthetic peptides epitopes (UreB158-172, UreB181-195, UreB211-225, UreB349-363, HpaA132-141, and HSP60189-203). In addition, oral therapeutic immunization with CWAE significantly reduced the number of H. pylori colonies in the stomach of Mongolian gerbils, compared with oral immunization using CTB-UE or H. pylori urease. The protection of CWAE was associated with higher levels of mixed CD4(+) T cell (Th cell) response, IgG, and secretory IgA (sIgA) antibodies to H. pylori. These results indic ate that a multivalent epitope

  17. Oral Immunization with a Multivalent Epitope-Based Vaccine, Based on NAP, Urease, HSP60, and HpaA, Provides Therapeutic Effect on H. pylori Infection in Mongolian gerbils

    Directory of Open Access Journals (Sweden)

    Le Guo

    2017-08-01

    Full Text Available Epitope-based vaccine is a promising strategy for therapeutic vaccination against Helicobacter pylori (H. pylori infection. A multivalent subunit vaccine containing various antigens from H. pylori is superior to a univalent subunit vaccine. However, whether a multivalent epitope-based vaccine is superior to a univalent epitope-based vaccine in therapeutic vaccination against H. pylori, remains unclear. In this study, a multivalent epitope-based vaccine named CWAE against H. pylori urease, neutrophil-activating protein (NAP, heat shock protein 60 (HSP60 and H. pylori adhesin A (HpaA was constructed based on mucosal adjuvant cholera toxin B subunit (CTB, Th1-type adjuvant NAP, multiple copies of selected B and Th cell epitopes (UreA27–53, UreA183–203, HpaA132–141, and HSP60189–203, and also the epitope-rich regions of urease B subunit (UreB158–251 and UreB321–385 predicted by bioinformatics. Immunological properties of CWAE vaccine were characterized in BALB/c mice model. Its therapeutic effect was evaluated in H. pylori-infected Mongolian gerbil model by comparing with a univalent epitope-based vaccine CTB-UE against H. pylori urease that was constructed in our previous studies. Both CWAE and CTB-UE could induce similar levels of specific antibodies against H. pylori urease, and had similar inhibition effect of H. pylori urease activity. However, only CWAE could induce high levels of specific antibodies to NAP, HSP60, HpaA, and also the synthetic peptides epitopes (UreB158–172, UreB181–195, UreB211–225, UreB349–363, HpaA132–141, and HSP60189–203. In addition, oral therapeutic immunization with CWAE significantly reduced the number of H. pylori colonies in the stomach of Mongolian gerbils, compared with oral immunization using CTB-UE or H. pylori urease. The protection of CWAE was associated with higher levels of mixed CD4+ T cell (Th cell response, IgG, and secretory IgA (sIgA antibodies to H. pylori. These results indic

  18. Uptake of Helicobacter pylori outer membrane vesicles by gastric epithelial cells.

    Science.gov (United States)

    Parker, Heather; Chitcholtan, Kenny; Hampton, Mark B; Keenan, Jacqueline I

    2010-12-01

    Helicobacter pylori bacteria colonize the human stomach where they stimulate a persistent inflammatory response. H. pylori is considered noninvasive; however, lipopolysaccharide (LPS)-enriched outer membrane vesicles (OMV), continuously shed from the surface of this bacterium, are observed within gastric epithelial cells. The mechanism of vesicle uptake is poorly understood, and this study was undertaken to examine the roles of bacterial VacA cytotoxin and LPS in OMV binding and cholesterol and clathrin-mediated endocytosis in vesicle uptake by gastric epithelial cells. OMV association was examined using a fluorescent membrane dye to label OMV, and a comparison was made between the associations of vesicles from a VacA(+) strain and OMV from a VacA(-) isogenic mutant strain. Within 20 min, essentially all associated OMV were intracellular, and vesicle binding appeared to be facilitated by the presence of VacA cytotoxin. Uptake of vesicles from the VacA(+) strain was inhibited by H. pylori LPS (58% inhibition with 50 μg/ml LPS), while uptake of OMV from the VacA(-) mutant strain was less affected (25% inhibition with 50 μg/ml LPS). Vesicle uptake did not require cholesterol. However, uptake of OMV from the VacA(-) mutant strain was inhibited by a reduction in clathrin-mediated endocytosis (42% with 15 μg/ml chlorpromazine), while uptake of OMV from the VacA(+) strain was less affected (25% inhibition with 15 μg/ml chlorpromazine). We conclude that VacA toxin enhances the association of H. pylori OMV with cells and that the presence of the toxin may allow vesicles to exploit more than one pathway of internalization.

  19. Uptake of Helicobacter pylori Outer Membrane Vesicles by Gastric Epithelial Cells▿

    Science.gov (United States)

    Parker, Heather; Chitcholtan, Kenny; Hampton, Mark B.; Keenan, Jacqueline I.

    2010-01-01

    Helicobacter pylori bacteria colonize the human stomach where they stimulate a persistent inflammatory response. H. pylori is considered noninvasive; however, lipopolysaccharide (LPS)-enriched outer membrane vesicles (OMV), continuously shed from the surface of this bacterium, are observed within gastric epithelial cells. The mechanism of vesicle uptake is poorly understood, and this study was undertaken to examine the roles of bacterial VacA cytotoxin and LPS in OMV binding and cholesterol and clathrin-mediated endocytosis in vesicle uptake by gastric epithelial cells. OMV association was examined using a fluorescent membrane dye to label OMV, and a comparison was made between the associations of vesicles from a VacA+ strain and OMV from a VacA− isogenic mutant strain. Within 20 min, essentially all associated OMV were intracellular, and vesicle binding appeared to be facilitated by the presence of VacA cytotoxin. Uptake of vesicles from the VacA+ strain was inhibited by H. pylori LPS (58% inhibition with 50 μg/ml LPS), while uptake of OMV from the VacA− mutant strain was less affected (25% inhibition with 50 μg/ml LPS). Vesicle uptake did not require cholesterol. However, uptake of OMV from the VacA− mutant strain was inhibited by a reduction in clathrin-mediated endocytosis (42% with 15 μg/ml chlorpromazine), while uptake of OMV from the VacA+ strain was less affected (25% inhibition with 15 μg/ml chlorpromazine). We conclude that VacA toxin enhances the association of H. pylori OMV with cells and that the presence of the toxin may allow vesicles to exploit more than one pathway of internalization. PMID:20876296

  20. Organelle Size Scaling of the Budding Yeast Vacuole by Relative Growth and Inheritance.

    Science.gov (United States)

    Chan, Yee-Hung M; Reyes, Lorena; Sohail, Saba M; Tran, Nancy K; Marshall, Wallace F

    2016-05-09

    It has long been noted that larger animals have larger organs compared to smaller animals of the same species, a phenomenon termed scaling [1]. Julian Huxley proposed an appealingly simple model of "relative growth"-in which an organ and the whole body grow with their own intrinsic rates [2]-that was invoked to explain scaling in organs from fiddler crab claws to human brains. Because organ size is regulated by complex, unpredictable pathways [3], it remains unclear whether scaling requires feedback mechanisms to regulate organ growth in response to organ or body size. The molecular pathways governing organelle biogenesis are simpler than organogenesis, and therefore organelle size scaling in the cell provides a more tractable case for testing Huxley's model. We ask the question: is it possible for organelle size scaling to arise if organelle growth is independent of organelle or cell size? Using the yeast vacuole as a model, we tested whether mutants defective in vacuole inheritance, vac8Δ and vac17Δ, tune vacuole biogenesis in response to perturbations in vacuole size. In vac8Δ/vac17Δ, vacuole scaling increases with the replicative age of the cell. Furthermore, vac8Δ/vac17Δ cells continued generating vacuole at roughly constant rates even when they had significantly larger vacuoles compared to wild-type. With support from computational modeling, these results suggest there is no feedback between vacuole biogenesis rates and vacuole or cell size. Rather, size scaling is determined by the relative growth rates of the vacuole and the cell, thus representing a cellular version of Huxley's model.

  1. Molecular markers for granulovacuolar degeneration are present in rimmed vacuoles.

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    Masahiro Nakamori

    Full Text Available BACKGROUND: Rimmed vacuoles (RVs are round-oval cytoplasmic inclusions, detected in muscle cells of patients with myopathies, such as inclusion body myositis (IBM and distal myopathy with RVs (DMRV. Granulovacuolar degeneration (GVD bodies are spherical vacuoles containing argentophilic and hematoxyphilic granules, and are one of the pathological hallmarks commonly found in hippocampal pyramidal neurons of patients with aging-related neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. These diseases are common in the elderly and share some pathological features. Therefore, we hypothesized that mechanisms of vacuolar formation in RVs and GVD bodies are common despite their role in two differing pathologies. We explored the components of RVs by immunohistochemistry, using antibodies for GVD markers. METHODS: Subjects included one AD case, eight cases of sporadic IBM, and three cases of DMRV. We compared immunoreactivity and staining patterns for GVD markers. These markers included: (1 tau-modifying proteins (caspase 3, cyclin-dependent kinase 5 [CDK5], casein kinase 1δ [CK1δ], and c-jun N-terminal kinase [JNK], (2 lipid raft-associated materials (annexin 2, leucine-rich repeat kinase 2 [LRRK2], and flotillin-1, and (3 other markers (charged multi-vesicular body protein 2B [CHMP2B] and phosphorylated transactive response DNA binding protein-43 [pTDP43] in both GVD bodies and RVs. Furthermore, we performed double staining of each GVD marker with pTDP43 to verify the co-localization. RESULTS: GVD markers, including lipid raft-associated proteins and tau kinases, were detected in RVs. CHMP2B, pTDP43, caspase 3, LRRK2, annexin 2 and flotillin-1 were detected on the rim and were diffusely distributed in the cytoplasm of RV-positive fibers. CDK5, CK1δ and JNK were detected only on the rim. In double staining experiments, all GVD markers colocalized with pTDP43 in RVs. CONCLUSIONS: These results suggest that RVs of muscle

  2. Helicobacter Pylori Seropostivity of Colon Cancer

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    F. Tugba Kos

    2014-03-01

    Full Text Available Aim: Until now many researches have showed that Helicobacter pylori infection may be etiological factor of colorectal cancer. The aim of current study was to investigate the frequency of H.pylori infection seropositivity of colorectal cancer patients and compare the clinicopathological features of H.pylori positive patients with negative ones. Material and Method: Seventy four colorectal patients were included in study. Retrospectively, patients clinical features, surgery history and pathological characteristics were screened. Patients group serum samples were collected. H.pylori Ig G level were quantitatively measured with ELISA method and levels above 5 arbU/ml were accepted as seropositive. Results: Patients median age was 60.5 ( range 26-83 and 56.8% (n=42 were male. H.pylori Ig G was positive in 37.8% (n=28 and negative in 62.2% (n=46 of patient group. H.pylori serpositive and negative patients median age of diagnosis were 56 and 64 respectively (p=0.01. There were no significant difference between H.pylori seropositive group when compared with negative group according to age, level of CEA and Ca 19-9, stage, lymph node involvement, perineural and vascular invasion, presence of polyps, differantion, localisation of tumours. Discussion: H.pylori seropositive patients were diagnosed at younger age. Association of this finding with etiology was confusing. Further studies with healthy controls may provide detailed information about whether H.pylori seropositivity is associated with colorectal cancer etiology.

  3. 3rd BRAZILIAN CONSENSUS ON Helicobacter pylori

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    Luiz Gonzaga Coelho

    2013-04-01

    Full Text Available Significant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.

  4. 3rd Brazilian Consensus on Helicobacter pylori.

    Science.gov (United States)

    Coelho, Luiz Gonzaga; Maguinilk, Ismael; Zaterka, Schlioma; Parente, José Miguel; do Carmo Friche Passos, Maria; Moraes-Filho, Joaquim Prado P

    2013-04-01

    Signicant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.

  5. Helicobacter pylori neutrophil activating protein as target for new drugs against H.pylori inflammation

    Institute of Scientific and Technical Information of China (English)

    Theodora Choli-Papadopoulou; Filippos Kottakis; Georgios Papadopoulos; Stefanos Pendas

    2011-01-01

    Helicobacter pylori (H. pylori ) infection is among the most common human infections and the major risk factor for peptic ulcer disease and gastric cancer. Within this work we present the implication of C-terminal region of H. pylori neutrophil activating protein in the stimulation of neutrophil activation as well as the evidence that the C-terminal region of H. pylori activating protein is indispensable for neutrophil adhesion to endothelial cells, a step necessary to H. pylori inflammation. In addition we show that arabino galactan proteins derived from chios mastic gum, the natural resin of the plant Pistacia lentiscus var. Chia inhibit neutrophil activation in vitro .

  6. Role of endodermal cell vacuoles in shoot gravitropism.

    Science.gov (United States)

    Kato, Takehide; Morita, Miyo Terao; Tasaka, Masao

    2002-06-01

    In higher plants, shoots and roots show negative and positive gravitropism, respectively. Data from surgical ablation experiments and analysis of starch deficient mutants have led to the suggestion that columella cells in the root cap function as gravity perception cells. On the other hand, endodermal cells are believed to be the statocytes (that is, gravity perceiving cells) of shoots. Statocytes in shoots and roots commonly contain amyloplasts which sediment under gravity. Through genetic research with Arabidopsis shoot gravitropism mutants, sgr1/scr and sgr7/shr, it was determined that endodermal cells are essential for shoot gravitropism. Moreover, some starch biosynthesis genes and EAL1 are important for the formation and maturation of amyloplasts in shoot endodermis. Thus, amyloplasts in the shoot endodermis would function as statoliths, just as in roots. The study of the sgr2 and zig/sgr4 mutants provides new insights into the early steps of shoot gravitropism, which still remains unclear. SGR2 and ZIG/SGR4 genes encode a phospholipase-like and a v-SNARE protein, respectively. Moreover, these genes are involved in vacuolar formation or function. Thus, the vacuole must play an important role in amyloplast sedimentation because the sgr2 and zig/sgr4 mutants display abnormal amyloplast sedimentation.

  7. Protection against Shiga Toxins

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    Simona Kavaliauskiene

    2017-02-01

    Full Text Available Shiga toxins consist of an A-moiety and five B-moieties able to bind the neutral glycosphingolipid globotriaosylceramide (Gb3 on the cell surface. To intoxicate cells efficiently, the toxin A-moiety has to be cleaved by furin and transported retrogradely to the Golgi apparatus and to the endoplasmic reticulum. The enzymatically active part of the A-moiety is then translocated to the cytosol, where it inhibits protein synthesis and in some cell types induces apoptosis. Protection of cells can be provided either by inhibiting binding of the toxin to cells or by interfering with any of the subsequent steps required for its toxic effect. In this article we provide a brief overview of the interaction of Shiga toxins with cells, describe some compounds and conditions found to protect cells against Shiga toxins, and discuss whether they might also provide protection in animals and humans.

  8. Helicobacter pylori: epidemiology and routes of transmission.

    Science.gov (United States)

    Brown, L M

    2000-01-01

    H. pylori is a common bacterium, and approximately 50 percent of the world's population has been estimated to be infected (198). Humans are the principal reservoir. The prevalence of H. pylori infection varies widely by geographic area, age, race, ethnicity, and SES. Rates appear to be higher in developing than in developed countries, with most of the infections occurring during childhood, and they seem to be decreasing with improvements in hygiene practices. H. pylori causes chronic gastritis and has been associated with several serious diseases of the gastrointestinal tract, including duodenal ulcer and gastric cancer. Since its "discovery" in 1982 by Warren and Marshall (1), H. pylori has been the topic of extensive research. A number of studies have used questionnaire components to investigate factors possibly related to the etiology of H. pylori infection. The majority of recent studies have not found tobacco use or alcohol consumption to be risk factors for H. pylori infection. Adequate nutritional status, especially frequent consumption of fruits and vegetables and of vitamin C, appears to protect against infection with H. pylori. In contrast, food prepared under less than ideal conditions or exposed to contaminated water or soil may increase the risk. Overall, inadequate sanitation practices, low social class, and crowded or high-density living conditions seem to be related to a higher prevalence of H. pylori infection. This finding suggests that poor hygiene and crowded conditions may facilitate transmission of infection among family members and is consistent with data on intrafamilial and institutional clustering of H. pylori infection. Understanding the route of H. pylori transmission is important if public health measures to prevent its spread are to be implemented. Iatrogenic transmission of H. pylori following endoscopy is the only proven mode. For the general population, the most likely mode of transmission is from person to person, by either the

  9. In vivo accumulation of Helicobacter pylori products, NOD1, ubiquitinated proteins and proteasome in a novel cytoplasmic structure.

    Directory of Open Access Journals (Sweden)

    Vittorio Necchi

    Full Text Available Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer, are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasome-enriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance.

  10. In vivo accumulation of Helicobacter pylori products, NOD1, ubiquitinated proteins and proteasome in a novel cytoplasmic structure.

    Science.gov (United States)

    Necchi, Vittorio; Sommi, Patrizia; Ricci, Vittorio; Solcia, Enrico

    2010-03-16

    Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer), are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS) we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasome-enriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance.

  11. In Vivo Accumulation of Helicobacter pylori Products, NOD1, Ubiquitinated Proteins and Proteasome in a Novel Cytoplasmic Structure

    Science.gov (United States)

    Necchi, Vittorio; Sommi, Patrizia; Ricci, Vittorio; Solcia, Enrico

    2010-01-01

    Cell internalization and intracellular fate of H. pylori products/virulence factors in vivo by human gastric epithelium, the main target of H. pylori-induced pathologies (i.e., peptic ulcer and cancer), are still largely unknown. Investigating gastric endoscopic biopsies from dyspeptic patients by means of ultrastructural immunocytochemistry, here we show that, in human superficial-foveolar epithelium and its metaplastic or dysplastic foci, H. pylori virulence factors accumulated in a discrete cytoplasmic structure characterized by 13-nm-thick cylindrical particles of regular punctate-linear substructure resembling the proteasome complex in size and structure. Inside this particle-rich cytoplasmic structure (PaCS) we observed colocalization of VacA, CagA, urease and outer membrane proteins with NOD1 receptor, ubiquitin-activating enzyme E1, polyubiquitinated proteins, proteasome components and potentially oncogenic proteins like SHP2 and ERKs in human gastric epithelium. By means of electron and confocal microscopy, we demonstrate that the in vivo findings were reproduced in vitro by incubating human epithelial cell lines with H. pylori products/virulence factors. PaCSs differed from VacA-induced vacuoles, phagosomes, aggresomes or related bodies. Our data suggest that PaCS is a novel, proteasome-enriched structure arising in ribosome-rich cytoplasm at sites of H. pylori products accumulation. As a site of selective concentration of bacterial virulence factors, the ubiquitin-proteasome system and interactive proteins, PaCS is likely to modulate immune-inflammatory and proliferative responses of the gastric epithelium of potential pathologic relevance. PMID:20300534

  12. Helicobacter pylori-induced activation of β-catenin involves low density lipoprotein receptor-related protein 6 and Dishevelled

    Directory of Open Access Journals (Sweden)

    Lendeckel Uwe

    2010-02-01

    Full Text Available Abstract Background The human microbial pathogen Helicobacter pylori resides in the stomach of about fifty percent of the world's population and represents a risk factor for chronic gastritis, peptic ulcers and, in rare cases, gastric cancer. Alterations of the Wnt/β-catenin signaling pathway have been described in almost every human cancer disease, due to the regulation of target genes being involved in cell cycle control, differentiation, cell migration or stem cell control. Our study aimed to elucidate the role of proximal Wnt signaling components low density lipoprotein receptor-related protein 6 (LRP6 and Dishevelled (Dvl in the activation of β-catenin early after infection of gastric epithelial cells with H. pylori. Results Infection of gastric epithelial NCI-N87 cells with H. pylori induces rapid phosphorylation of the Wnt/β-catenin pathway co-receptor LRP6 independent of the cytotoxin-associated gene A (CagA or vacuolating cytotoxin A (VacA. However, bacteria lacking a functional type 4 secretion system (T4SS failed to induce LRP6 phosphorylation. Further, we identified proteins of the Dvl family, namely Dvl2 and Dvl3, which are involved in LRP6 phosphorylation. H. pylori-induced nuclear accumulation of β-catenin and its transcriptional activation, and expression of Wnt target genes are strongly reduced in stable knockdown cell lines deficient for LRP6, Dvl2 or Dvl3. Conclusion We analysed the H. pylori-induced activation of Wnt-signaling factors and demonstrate for the first time that the canonical Wnt-signaling proteins LRP6 and Dvl2 and Dvl3 are involved in the regulation of β-catenin.

  13. Phytochelatin-metal(loid) transport into vacuoles shows different substrate preferences in barley and Arabidopsis.

    Science.gov (United States)

    Song, Won-Yong; Mendoza-Cózatl, David G; Lee, Youngsook; Schroeder, Julian I; Ahn, Sang-Nag; Lee, Hyun-Sook; Wicker, Thomas; Martinoia, Enrico

    2014-05-01

    Cadmium (Cd) and arsenic (As) are toxic to all living organisms, including plants and humans. In plants, Cd and As are detoxified by phytochelatins (PCs) and metal(loid)-chelating peptides and by sequestering PC-metal(loid) complexes in vacuoles. Consistent differences have been observed between As and Cd detoxification. Whereas chelation of Cd by PCs is largely sufficient to detoxify Cd, As-PC complexes must be sequestered into vacuoles to be fully detoxified. It is not clear whether this difference in detoxification pathways is ubiquitous among plants or varies across species. Here, we have conducted a PC transport study using vacuoles isolated from Arabidopsis and barley. Arabidopsis vacuoles accumulated low levels of PC2 -Cd, and vesicles from yeast cells expressing either AtABCC1 or AtABCC2 exhibited negligible PC2 -Cd transport activity compared with PC2 -As. In contrast, barley vacuoles readily accumulated comparable levels of PC2 -Cd and PC2 -As. PC transport in barley vacuoles was inhibited by vanadate, but not by ammonium, suggesting the involvement of ABC-type transporters. Interestingly, barley vacuoles exhibited enhanced PC2 transport activity when essential metal ions, such as Zn(II), Cu(II) and Mn(II), were added to the transport assay, suggesting that PCs might contribute to the homeostasis of essential metals and detoxification of non-essential toxic metal(loid)s.

  14. The Water to Solute Permeability Ratio Governs the Osmotic Volume Dynamics in Beetroot Vacuoles

    Science.gov (United States)

    Vitali, Victoria; Sutka, Moira; Amodeo, Gabriela; Chara, Osvaldo; Ozu, Marcelo

    2016-01-01

    Plant cell vacuoles occupy up to 90% of the cell volume and, beyond their physiological function, are constantly subjected to water and solute exchange. The osmotic flow and vacuole volume dynamics relies on the vacuole membrane -the tonoplast- and its capacity to regulate its permeability to both water and solutes. The osmotic permeability coefficient (Pf) is the parameter that better characterizes the water transport when submitted to an osmotic gradient. Usually, Pf determinations are made in vitro from the initial rate of volume change, when a fast (almost instantaneous) osmolality change occurs. When aquaporins are present, it is accepted that initial volume changes are only due to water movements. However, in living cells osmotic changes are not necessarily abrupt but gradually imposed. Under these conditions, water flux might not be the only relevant driving force shaping the vacuole volume response. In this study, we quantitatively investigated volume dynamics of isolated Beta vulgaris root vacuoles under progressively applied osmotic gradients at different pH, a condition that modifies the tonoplast Pf. We followed the vacuole volume changes while simultaneously determining the external osmolality time-courses and analyzing these data with mathematical modeling. Our findings indicate that vacuole volume changes, under progressively applied osmotic gradients, would not depend on the membrane elastic properties, nor on the non-osmotic volume of the vacuole, but on water and solute fluxes across the tonoplast. We found that the volume of the vacuole at the steady state is determined by the ratio of water to solute permeabilites (Pf/Ps), which in turn is ruled by pH. The dependence of the permeability ratio on pH can be interpreted in terms of the degree of aquaporin inhibition and the consequently solute transport modulation. This is relevant in many plant organs such as root, leaves, cotyledons, or stems that perform extensive rhythmic growth movements

  15. The water to solute permeability ratio governs the osmotic volume dynamics in beetroot vacuoles

    Directory of Open Access Journals (Sweden)

    Victoria Vitali

    2016-09-01

    Full Text Available Plant cell vacuoles occupy up to 90% of the cell volume and, beyond their physiological function, are constantly subjected to water and solute exchange. The osmotic flow and vacuole volume dynamics relies on the vacuole membrane -the tonoplast- and its capacity to regulate its permeability to both water and solutes. The osmotic permeability coefficient (Pf is the parameter that better characterizes the water transport when submitted to an osmotic gradient. Usually, Pf determinations are made in vitro from the initial rate of volume change, when a fast (almost instantaneous osmolality change occurs. When aquaporins are present, it is accepted that initial volume changes are only due to water movements. However, in living cells osmotic changes are not necessarily abrupt but gradually imposed. Under these conditions, water flux might not be the only relevant driving force shaping the vacuole volume response. In this study, we quantitatively investigated volume dynamics of isolated Beta vulgaris root vacuoles under progressively applied osmotic gradients at different pH, a condition that modifies the tonoplast Pf. We followed the vacuole volume changes while simultaneously determining the external osmolality time-courses and analyzing these data with mathematical modelling. Our findings indicate that vacuole volume changes, under progressively applied osmotic gradients, would not depend on the membrane elastic properties, nor on the non-osmotic volume of the vacuole, but on water and solute fluxes across the tonoplast. We found that the volume of the vacuole at the steady state is determined by the ratio of water to solute permeabilites (Pf/Ps, which in turn is ruled by pH. The dependence of the permeability ratio on pH can be interpreted in terms of the degree of aquaporin inhibition and the consequently solute transport modulation. This is relevant in many plant organs such as root, leaves, cotyledons or stems that perform extensive rhythmic

  16. Helicobacter pylori: recent advances in the study of its pathogenicity and prevention Helicobacter pylori: avances recientes en el estudio de su prevención y patogenicidad

    Directory of Open Access Journals (Sweden)

    Germán R. Aguilar

    2001-06-01

    Full Text Available Helicobacter pylori has acquired great importance during the last two decades, after being recognized as an important pathogen that infects a great portion of the human population. This microorganism is recognized as the main causal agent of chronic gastritis and duodenal ulcers, and it is associated with the subsequent development of gastric carcinoma. The pathogenic mechanisms of H. pylori and their relation to gastric ailments have not been clearly defined. However, at present it is well established that urease, vacuolating cytotoxin VacA, and the pathogenicity island (cag PAI gene products, are the main factors of virulence of this organism. Thus, individuals infected with strains that express these virulence factors probably develop a severe local inflammation that may induce the development of peptic ulcer and gastric cancer. The way the infection spreads throughout the world suggests the possibility that there are multiple pathways of transmission. Due to the importance that H. pylori has acquired as a human pathogen, laboratories worldwide are attempting to develop a vaccine that confers long-term immunological protection against infection by this microorganism. Hence, the objective of this review is to present the most relevant findings of the biology of H. Pylori and its interaction with the human host. The full version of this paper is available too at: http://www.insp.mx/salud/index.htmlHelicobacter pylori ha adquirido gran importancia durante las últimas dos décadas, al ser reconocido como un importante patógeno que infecta una gran porción de la población humana. Este microrganismo es reconocido como el principal agente que causa la gastritis crónica y la úlcera duodenal, además de que se ha asociado con el subsecuente desarrollo del carcinoma gástrico. Los mecanismos patogénicos de H. pylori y su relación con los padecimientos gástricos no se han definido en forma clara. Sin embargo, actualmente está bien establecido

  17. Helicobacter pylori colonization of the oral cavity: A milestone discovery.

    Science.gov (United States)

    Yee, John K C

    2016-01-14

    Over the past several years, the severity of Helicobacter pylori (H. pylori) infections has not significantly diminished. After successful eradication, the annual H. pylori recurrence rate is approximately 13% due to oral H. pylori infection. Established clinical diagnostic techniques do not identify an oral etiologic basis of H. pylori prior to gastric infection. There has been disagreement as to whether oral infection of H. pylori exists or not, with no definite conclusion. In medical practice, negative results with the urea breath test suggest that the stomach infection of H. pylori is cured in these patients. In fact, patients can present negative urea breath test results and yet exhibit H. pylori infection due to oral infection. The present paper provides evidence that H. pylori oral infection is nonetheless present, and the oral cavity represents a secondary site for H. pylori colonization.

  18. Helicobacter pylori colonization of the oral cavity: A milestone discovery

    Science.gov (United States)

    Yee, John KC

    2016-01-01

    Over the past several years, the severity of Helicobacter pylori (H. pylori) infections has not significantly diminished. After successful eradication, the annual H. pylori recurrence rate is approximately 13% due to oral H. pylori infection. Established clinical diagnostic techniques do not identify an oral etiologic basis of H. pylori prior to gastric infection. There has been disagreement as to whether oral infection of H. pylori exists or not, with no definite conclusion. In medical practice, negative results with the urea breath test suggest that the stomach infection of H. pylori is cured in these patients. In fact, patients can present negative urea breath test results and yet exhibit H. pylori infection due to oral infection. The present paper provides evidence that H. pylori oral infection is nonetheless present, and the oral cavity represents a secondary site for H. pylori colonization. PMID:26811613

  19. Pathogenesis of Helicobacter pylori infection.

    Science.gov (United States)

    Camilo, Vania; Sugiyama, Toshiro; Touati, Eliette

    2017-09-01

    Helicobacter pylori is responsible for the most commonly found infection in the world's population. It is the major risk factor for gastric cancer development. Numerous studies published over the last year provide new insights into the strategies employed by H. pylori to adapt to the extreme acidic conditions of the gastric environment, to establish persistent infection and to deregulate host functions, leading to gastric pathogenesis and cancer. In this review, we report recent data on the mechanisms involved in chemotaxis, on the essential role of nickel in acid resistance and gastric colonization, on the importance of adhesins and Hop proteins and on the role of CagPAI-components and CagA. Among the host functions, a special focus has been made on the escape from immune response, the ability of bacteria to induce genetic instability and modulate telomeres, the mechanism of autophagy and the deregulation of micro RNAs. © 2017 John Wiley & Sons Ltd.

  20. Immune response to H pylori

    Institute of Scientific and Technical Information of China (English)

    Giovanni Suarez; Victor E Reyes; Ellen J Beswick

    2006-01-01

    The gastric mucosa separates the underlying tissue from the vast array of antigens that traffic through the stomach lumen. While the extreme pH of this environment is essential in aiding the activation of enzymes and food digestion, it also renders the gastric epithelium free from bacterial colonization, with the exception of one important human pathogen, H pylori. This bacterium has developed mechanisms to survive the harsh environment of the stomach, actively move through the mucosal layer,attach to the epithelium, evade immune responses, and achieve persistent colonization. While a hallmark of this infection is a marked inflammatory response with the infiltration of various immune cells into the infected gastric mucosa, the host immune response is unable to clear the infection and may actually contribute to the associated pathogenesis. Here, we review the host responses involved during infection with H pylori and how they are influenced by this bacterium.

  1. Content and vacuole extravacuole distribution of neutral sugars, free amino acids, and anthocyanin in protoplasts

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.J.

    1979-07-01

    Neutral sugar, free amino acid, and anthocyanin levels and vacuole/extravacuole distribution were determined for Hippeastrum and Tulipa petal and Tulipa leaf protoplasts. Glucose and fructose, the predominant neutral monosaccharides observed, were primarily vacuolar in location. Glutamine, the predominant free amino acid found, was primarily extravacuolar. ..gamma..-methyleneglutamate was identified as a major constituent of Tulipa protoplasts. Qualitative characterization of Hippeastrum petal and vacuole organic acids indicated the presence of oxalic, malic, citric, and isocitric acids. Data are presented which indicate that vacuoles obtained by gentle osmotic shock of protoplasts in dibasic phosphate have good purity and retain their contents.

  2. Understanding malarial toxins.

    Science.gov (United States)

    Starkl Renar, Katarina; Iskra, Jernej; Križaj, Igor

    2016-09-01

    Recognized since antiquity, malaria is one of the most infamous and widespread infectious diseases in humans and, although the death rate during the last century has been diminishing, it still accounts for more than a half million deaths annually. It is caused by the Plasmodium parasite and typical symptoms include fever, shivering, headache, diaphoresis and nausea, all resulting from an excessive inflammatory response induced by malarial toxins released into the victim's bloodstream. These toxins are hemozoin and glycosylphosphatidylinositols. The former is the final product of the parasite's detoxification of haeme, a by-product of haemoglobin catabolism, while the latter anchor proteins to the Plasmodium cell surface or occur as free molecules. Currently, only two groups of antimalarial toxin drugs exist on the market, quinolines and artemisinins. As we describe, they both target biosynthesis of hemozoin. Other substances, currently in various phases of clinical trials, are directed towards biosynthesis of glycosylphosphatidylinositol, formation of hemozoin, or attenuation of the inflammatory response of the patient. Among the innovative approaches to alleviating the effects of malarial toxins, is the development of antimalarial toxin vaccines. In this review the most important lessons learned from the use of treatments directed against the action of malarial toxins in antimalarial therapy are emphasized and the most relevant and promising directions for future research in obtaining novel antimalarial agents acting on malarial toxins are discussed.

  3. Helicobacter pylori infection and serum ferritin

    DEFF Research Database (Denmark)

    Berg, Gabriele; Bode, G; Blettner, M

    2001-01-01

    OBJECTIVE: Helicobacter pylori may possibly affect the iron metabolism by occult bleeding, impaired absorption of non-hem iron, and by scavenging hem iron or ferritin, as some studies have suggested. The aim of this study was to analyze the association between H. pylori infection and serum ferrit...

  4. Helicobacter pylori eradication for preventing gastric cancer.

    Science.gov (United States)

    Lu, Bin; Li, Meng

    2014-05-21

    Helicobacter pylori (H. pylori) infection is a major risk factor for gastric cancer (GC) development, which is one of the most challenging malignant diseases worldwide with limited treatments. In the multistep pathogenesis of GC, H. pylori infection slowly induces chronic active gastritis, which progresses through the premalignant stages of atrophic gastritis, intestinal metaplasia, and dysplasia, and then finally to GC. Although eradication of H. pylori is a reasonable approach for the prevention of GC, there have been some contradictory reports, with only some long-term follow-up data showing efficacy of this approach. The inconsistencies are likely due to the insufficient number of participants, relatively short follow-up periods, poor quality of study designs, and the degree and extent of preneoplastic changes at the time of H. pylori eradication. This review analyzes recent high-quality studies to resolve the discrepancies regarding the eradication of H. pylori for GC prevention. The relationship between H. pylori eradication and GC/precancerous lesions/metachronous GC is examined, and the cost-effectiveness of this strategy in the prevention of GC is assessed. Although it is assumed that eradication of H. pylori has the potential to prevent GC, the feasibility and appropriate timing of this strategy for cancer prevention remain to be determined. As a result, additional well-designed trials with longer follow-up periods are needed to clarify this issue.

  5. Helicobacter Pylori and Gastric Cancer: Clinical Aspects

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Song

    2015-01-01

    Full Text Available Objective: Although Helicobacter pylori (H. pylori is considered as the main etiological factor for gastric cancer, the strategy of screening and treating the oncogenic bacterium is still controversial. The objective was to evaluate the status and progress of the cognition about the relationship between H. pylori infection and gastric cancer from a clinical aspect. Data Sources: The data used in this review were mainly from the PubMed articles published in English from 1984 to 2015. Study Selection: Clinical research articles were selected mainly according to their level of relevance to this topic. Results: Gastric cancer is the fifth most common malignancy and the third leading cause of cancer deaths worldwide. The main etiological factor for gastric cancer is H. pylori infection. About 74.7-89.0% gastric cancer was related to H. pylori infection. Up to date, some regional gastric cancer prevention programs including the detection and treatment of H. pylori infection are under way. Current data obtained from the randomized controlled trials suggest that population-based H. pylori screening and treatment is feasible and cost-effective in preventing gastric cancer; however, a population-based H. pylori eradication campaign would potentially lead to bacterial resistance to the corresponding antibiotics, as well as a negative impact on the normal flora. Conclusions: The important questions of feasibility, program costs, appropriate target groups for intervention, and the potential harm of mass therapy with antibiotics must first be answered before implementing any large-scale program.

  6. Helicobacter pylori: From Infection to Cure

    Directory of Open Access Journals (Sweden)

    ABR Thomson

    1996-01-01

    Full Text Available Over 380 abstracts, presentations and posters of recent advances were highlighted at the European and International Helicobacter pylori meeting held July 7 to 9, 1995 in Edinburgh, Scotland. New advances abound, with major interest focusing on the simple, safe, inexpensive new `gold standard’ for H pylori eradication therapy: a single week of tid omeprazole 20 mg, metronidazole 400 mg and clarithromycin 250 mg, or omeprazole 20 mg, amoxicillin 1000 mg and clarithromycin 500 mg. To avoid false negative results, two biopsies must be taken from the antrum and two from the gastric body at least four weeks after completion of eradication therapy, and ideally should be supplemented with at least one further H pylori test such as a biopsy for urease activity or culture, or a urea breath test. While most patients with a gastric or duodenal ulcer (DU who do not consume nonsteroidal anti-inflammatory drugs are infected with H pylori, the association is much less apparent in those with a DU who present with an upper gastrointestinal hemorrhage. H pylori eradication for nonulcer dyspepsia is not widely recommended, and the patient with a DU given effective H pylori eradication who presents with dyspepsia likely has erosive esophagitis rather than recurrent DU or H pylori. Gastroenterologists are at increased risk of H pylori infection, particularly older gastroenterologists who are very busy endoscopists.

  7. Helicobacter pylori and non-malignant diseases.

    Science.gov (United States)

    Furuta, Takahisa; Delchier, Jean-Charles

    2009-09-01

    It is well known that Helicobacter pylori infection is associated with many nonmalignant disorders such as gastritis, peptic ulcer, gastroesophageal reflux disease (GERD), gastric polyp, nonsteroidal anti-inflammatory drug (NSAID)/aspirin-induced gastric injury, and functional dyspepsia. In 2008, interesting articles on the association of H. pylori infection with these disorders were presented, some of which intended to reveal the mechanisms of inter-individual differences in response to H. pylori infection, and have demonstrated that genetic differences in host and bacterial factors as well as environmental factors account for these differences. A decline in the occurrence of peptic ulcer related to H. pylori was confirmed. An inverse relationship between H. pylori infection and GERD was also confirmed but the impact of gastric atrophy on the prevention of GERD remained debatable. For NSAID-induced gastric injury, eradication of H. pylori infection has been recommended. During this year, eradication of H. pylori infection was recommended for patients treated with antiplatelet therapy as well as aspirin and NSAID. It was also reported that for patients with functional dyspepsia, eradication of H. pylori offers a modest but significant benefit.

  8. Molecular mimicry in Helicobacter pylori infections

    Science.gov (United States)

    Chmiela, Magdalena; Gonciarz, Weronika

    2017-01-01

    Gram-negative bacteria Helicobacter pylori (H. pylori) colonize gastric mucosa in humans and increase the risk of serious diseases such as gastric and duodenal ulcers, stomach cancers and mucosa associated lymphoid tissue lymphoma. The role of H. pylori infection in the pathogenesis of several extragastric diseases has been suggested including immune thrombocytopenic purpura, iron deficiency anemia, vitamin D deficiency, cardiovascular diseases, diabetes mellitus and dermatological disorders. Also neurological diseases and even lung cancer have attracted researchers concern. The relation between H. pylori infection and a growth retardation in children has also been suggested. Many mechanisms of molecular mimicry between H. pylori and the host have been proposed as a pathogen strategy to manipulate the immune system of the host in order to remain unrecognized and avoid eradication. A lot of effort has been put into the demonstration of homologous sequences between H. pylori and host compounds. However, knowledge about how often autoantibodies or autoreactive T lymphocytes induced during H. pylori infections cause pathological disorders is insufficient. This review provides data on H. pylori antigenic mimicry and possible deleterious effects due to the induction of immune response to the components common to these bacteria and the host. PMID:28652651

  9. Alcohol consumption and Helicobacter pylori infection

    DEFF Research Database (Denmark)

    Brenner, H; Berg, Gabriele; Lappus, N

    1999-01-01

    Alcohol has strong antimicrobial activity and stimulates gastric acid secretion. Alcohol consumption may therefore compromise the living conditions of Helicobacter pylori in the stomach. We assessed the relation of alcohol consumption with H. pylori infection among 1,785 participants ages 18...

  10. Molecular mimicry in Helicobacter pylori infections.

    Science.gov (United States)

    Chmiela, Magdalena; Gonciarz, Weronika

    2017-06-14

    Gram-negative bacteria Helicobacter pylori (H. pylori) colonize gastric mucosa in humans and increase the risk of serious diseases such as gastric and duodenal ulcers, stomach cancers and mucosa associated lymphoid tissue lymphoma. The role of H. pylori infection in the pathogenesis of several extragastric diseases has been suggested including immune thrombocytopenic purpura, iron deficiency anemia, vitamin D deficiency, cardiovascular diseases, diabetes mellitus and dermatological disorders. Also neurological diseases and even lung cancer have attracted researchers concern. The relation between H. pylori infection and a growth retardation in children has also been suggested. Many mechanisms of molecular mimicry between H. pylori and the host have been proposed as a pathogen strategy to manipulate the immune system of the host in order to remain unrecognized and avoid eradication. A lot of effort has been put into the demonstration of homologous sequences between H. pylori and host compounds. However, knowledge about how often autoantibodies or autoreactive T lymphocytes induced during H. pylori infections cause pathological disorders is insufficient. This review provides data on H. pylori antigenic mimicry and possible deleterious effects due to the induction of immune response to the components common to these bacteria and the host.

  11. Helicobacter pylori therapy:Present and future

    Institute of Scientific and Technical Information of China (English)

    Vincenzo; De; Francesco; Enzo; Ierardi; Cesare; Hassan; Angelo; Zullo

    2012-01-01

    Helicobacter pylori(H.pylori) plays a crucial role in the pathogenesis of chronic active gastritis,peptic ulcer and gastric mucosa-associated lymphoid tissue-lymphoma,and is also involved in carcinogenesis of the stomach.H.pylori treatment still remains a challenge for physicians,since no current first-line therapy is able to cure the infection in all treated patients.Several factors may help in the eradication of therapy failure.We reviewed both bacterial and host factors involved in therapeutic management of the H.pylori infection.In addition,we evaluated data on the most successful therapy regimens-sequential and concomitant therapies-currently available for H.pylori eradication.

  12. Role of Helicobacter pylori in functional dyspepsia

    Institute of Scientific and Technical Information of China (English)

    Colm O'Morain

    2006-01-01

    The aetiology of dyspepsia is unknown in the majority of patients. Helicobacter pylori(H pylori) is the cause in a subset of patients. A non invasive test to assess the presence of H pylori is recommended in the management of patients under the age of 50 presenting to a family practitioner with dyspepsia. A urea breath test or a stool antigen test are the most reliable non invasive tests. Eradication of H pylori will reduce the risk to the patient with dyspepsia of developing a peptic ulcer, reduce the complication rate if prescribed nonsteroid anti-inflammatory drugs and later reduce the risk of gastric cancer. The recommended treatment for non ulcer dyspepsia associated with a H pylori infection should be a 10-d course of treatment with a PPI and two antibiotics. Treatment efficacy should be assessed four weeks after completing treatment with a urea breath test or a stool antigen test.

  13. Helicobacter pylori, Cancer, and the Gastric Microbiota.

    Science.gov (United States)

    Wroblewski, Lydia E; Peek, Richard M

    Gastric adenocarcinoma is one of the leading causes of cancer-related death worldwide and Helicobacter pylori infection is the strongest known risk factor for this disease. Although the stomach was once thought to be a sterile environment, it is now known to house many bacterial species leading to a complex interplay between H. pylori and other residents of the gastric microbiota. In addition to the role of H. pylori virulence factors, host genetic polymorphisms, and diet, it is now becoming clear that components of the gastrointestinal microbiota may also influence H. pylori-induced pathogenesis. In this chapter, we discuss emerging data regarding the gastric microbiota in humans and animal models and alterations that occur to the composition of the gastric microbiota in the presence of H. pylori infection that may augment the risk of developing gastric cancer.

  14. STUDY OF THE DYNAMIC OF HELICOBACTER PYLORI INFECTION PREVALENCE IN DIFFERENT AGE GROUPS OF ST. PETERSBURG POPULATION IN 2007-2011

    Directory of Open Access Journals (Sweden)

    A. V. Svarval

    2012-01-01

    Full Text Available Abstract. Presence of specific antibodies to H. pylori and to its Cag A toxin was studied in 1917 persons, including 860 children and 1057 adults, in Pasteur Research Institute of Epidemiology and Microbiology, St. Petersburg, Russia. The studied group was presented by the subjectively healthy individuals and blood donors living in St. Petersburg. The growth and stabilization of serological positive rates to H. pilory at high level, as well as increasing the proportion of CagA-positive infection among children and adults in St. Petersburg in 2007–2011 have been established. There are 3 age risk groups of H. pylori infection among children population: 4–5 years, 7–8 years and 14–15 years. The shift of the maximum H. pylori seropositivity rates from age group of 30–39 years in 2007 to age group 40–49 years in 2011 was detected.

  15. A soluble acid invertase is directed to the vacuole by a signal anchor mechanism.

    Science.gov (United States)

    Rae, Anne L; Casu, Rosanne E; Perroux, Jai M; Jackson, Mark A; Grof, Christopher P L

    2011-06-15

    Enzyme activities in the vacuole have an important impact on the net concentration of sucrose. In sugarcane (Saccharum hybrid), immunolabelling demonstrated that a soluble acid invertase (β-fructofuranosidase; EC 3.2.1.26) is present in the vacuole of storage parenchyma cells during sucrose accumulation. Examination of sequences from sugarcane, barley and rice showed that the N-terminus of the invertase sequence contains a signal anchor and a tyrosine motif, characteristic of single-pass membrane proteins destined for lysosomal compartments. The N-terminal peptide from the barley invertase was shown to be capable of directing the green fluorescent protein to the vacuole in sugarcane cells. The results suggest that soluble acid invertase is sorted to the vacuole in a membrane-bound form.

  16. Localization of acid hydrolases in protoplasts. Examination of the proposed lysosomal function of the mature vacuole

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, H.C.; Wagner, G.J.; Siegelman, H.W.

    1977-06-01

    The development of techniques to isolate and purify relatively large quantities of intact vacuoles from mature tissues permits direct biochemical analysis of this ubiquitous mature plant cell organelle. Vacuoles and a fraction enriched in soluble cytoplasmic constituents were quantitatively prepared from Hippeastrum flower petal protoplasts. Vacuolar lysate and soluble cytoplasmic fractions were examined for acid hydrolase activities commonly associated with animal lysosomes, and pH optima were determined. Esterase, protease, carboxypeptidase, ..beta..-galactosidase, ..cap alpha..-glycosidase and ..beta..-glycosidase, not found in the vacuole lysate fraction, were components of the soluble cytoplasmic fraction. Acid phosphatase, RNase and DNase were present in both fractions. Vacuolar enzyme activities were also examined as a function of flower development from bud through senescent stages. The data obtained are not consistent with the concept that the mature plant cell vacuole functions as a generalized lysosome.

  17. THE TONOPLAST TRANSPORT SYSTEMS OF PLANT VACUOLES AND THEIR POTENTIAL APPLICATION IN BIOTECHNOLOGY

    Directory of Open Access Journals (Sweden)

    S. V. Isayenkov

    2013-06-01

    Full Text Available The pivotal role of plant vacuoles in plant survival was discussed in the review. Particularly, the providing of cellular turgor, accumulation of inorganic osmolytes and nutrients are the primary tasks of these cellular organelles. The main mechanisms of tonoplast transport systems were described. The known transport pathways of minerals, heavy metals, vitamins and other organic compounds were classified and outlined. The main systems of membrane vacuolar transport were reviewed. The outline of the physiological functions and features of vacuolar membrane transport proteins were performed. The physiological role of transport of minerals, nutrients and other compounds into vacuoles were discussed. This article reviews the main types of plant vacuoles and their functional role in plant cell. Current state and progress in vacuolar transport research was outlined. The examples of application for rinciples and mechanisms of vacuolar membrane transport in plant biotechnology were iven. The perspectives and approaches in plant and food biotechnology concerning transport and physiology of vacuoles are discussed.

  18. Characterization of the anion sensitive ATPase in intact vacuoles of Kalanchoe diagremontiana

    Energy Technology Data Exchange (ETDEWEB)

    Kobza, J.; Uribe, E.G.

    1986-04-01

    A method for the isolation of intact vacuoles from K. daigremontiana was developed which produced high yields of relatively pure vacuoles as determined by marker enzyme contamination. Upon isolation, the vacuoles were stabilized by the inclusion of 5% (w/v) ficoll. Enzyme activity was insensitive to vanadate and azide but was strongly inhibited by DCCD. Enzyme activity was strictly dependent on the inclusion of Mg/sup 2 +/ and was stimulated by anions as depicted by the series, NO/sub 3//sup -/ < Br/sup -/ < SO/sub 4//sup -/ < HCO/sub 3//sup -/ < Cl/sup -/. It was found that in intact vacuoles the ATPase activity was stimulated by phosphate to a level equivalent to that found with the chloride. The enzyme exhibited Michaelis-Menten kinetics with a Km for Mg-ATP complex of 0.51 mM.

  19. Oculopharyngeal Weakness, Hypophrenia, Deafness, and Impaired Vision: A Novel Autosomal Dominant Myopathy with Rimmed Vacuoles

    Directory of Open Access Journals (Sweden)

    Ting Chen

    2016-01-01

    Conclusions: We reported a novel autosomal dominant myopathy with rimmed vacuoles characterized by dysarthria, dysphagia, external ophthalmoplegia, limb weakness, hypophrenia, deafness, and impaired vision, but the causative gene has not been found and needs further study.

  20. Staphylococcus aureus toxins.

    Science.gov (United States)

    Otto, Michael

    2014-02-01

    Staphylococcus aureus is a dangerous pathogen that causes a variety of severe diseases. The virulence of S. aureus is defined by a large repertoire of virulence factors, among which secreted toxins play a preeminent role. Many S. aureus toxins damage biological membranes, leading to cell death. In particular, S. aureus produces potent hemolysins and leukotoxins. Among the latter, some were recently identified to lyse neutrophils after ingestion, representing an especially powerful weapon against bacterial elimination by innate host defense. Furthermore, S. aureus secretes many factors that inhibit the complement cascade or prevent recognition by host defenses. Several further toxins add to this multi-faceted program of S. aureus to evade elimination in the host. This review will give an overview over S. aureus toxins focusing on recent advances in our understanding of how leukotoxins work in receptor-mediated or receptor-independent fashions.

  1. Signal transduction of Helicobacter pylori during interaction with host cell protein receptors of epithelial and immune cells

    Science.gov (United States)

    Pachathundikandi, Suneesh Kumar; Tegtmeyer, Nicole; Backert, Steffen

    2013-01-01

    Helicobacter pylori infections can induce pathologies ranging from chronic gastritis, peptic ulceration to gastric cancer. Bacterial isolates harbor numerous well-known adhesins, vacuolating cytotoxin VacA, protease HtrA, urease, peptidoglycan, and type IV secretion systems (T4SS). It appears that H. pylori targets more than 40 known host protein receptors on epithelial or immune cells. A series of T4SS components such as CagL, CagI, CagY, and CagA can bind to the integrin α5β1 receptor. Other targeted membrane-based receptors include the integrins αvβ3, αvβ5, and β2 (CD18), RPTP-α/β, GP130, E-cadherin, fibronectin, laminin, CD46, CD74, ICAM1/LFA1, T-cell receptor, Toll-like receptors, and receptor tyrosine kinases EGFR, ErbB2, ErbB3, and c-Met. In addition, H. pylori is able to activate the intracellular receptors NOD1, NOD2, and NLRP3 with important roles in innate immunity. Here we review the interplay of various bacterial factors with host protein receptors. The contribution of these interactions to signal transduction and pathogenesis is discussed. PMID:24280762

  2. Enhanced Membrane Fusion in Sterol-enriched Vacuoles Bypasses the Vrp1p RequirementD⃞

    OpenAIRE

    Tedrick, Kelly; Trischuk, Tim; Lehner, Richard; Eitzen, Gary

    2004-01-01

    Organization of lipids into membrane microdomains is a vital mechanism of protein processing. Here we show that overexpression of ERG6, a gene involved in ergosterol synthesis, elevates sterol levels 1.5-fold on the vacuole membrane and enhances their homotypic fusion. The mechanism of sterol-enhanced fusion is not via more efficient sorting, but instead promotes increased kinetics of fusion subreactions. We initially isolated ERG6 as a suppressor of a vrp1Δ growth defect selective for vacuol...

  3. Enhanced Membrane Fusion in Sterol-enriched Vacuoles Bypasses the Vrp1p RequirementD⃞

    OpenAIRE

    Tedrick, Kelly; Trischuk, Tim; Lehner, Richard; Eitzen, Gary

    2004-01-01

    Organization of lipids into membrane microdomains is a vital mechanism of protein processing. Here we show that overexpression of ERG6, a gene involved in ergosterol synthesis, elevates sterol levels 1.5-fold on the vacuole membrane and enhances their homotypic fusion. The mechanism of sterol-enhanced fusion is not via more efficient sorting, but instead promotes increased kinetics of fusion subreactions. We initially isolated ERG6 as a suppressor of a vrp1Δ growth defect selective for vacuol...

  4. Helicobacter pylori and pregnancy-related disorders

    Science.gov (United States)

    Cardaropoli, Simona; Rolfo, Alessandro; Todros, Tullia

    2014-01-01

    Helicobacter pylori (H. pylori) infection is investigated in gastric diseases even during pregnancy. In particular, this Gram-negative bacterium seems to be associated with hyperemesis gravidarum, a severe form of nausea and vomiting during pregnancy. During the last decade, the relationship among H. pylori and several extra-gastric diseases strongly emerged in literature. The correlation among H. pylori infection and pregnancy-related disorders was mainly focused on iron deficiency anemia, thrombocytopenia, fetal malformations, miscarriage, pre-eclampsia and fetal growth restriction. H. pylori infection may have a role in the pathogenesis of various pregnancy-related disorders through different mechanisms: depletion of micronutrients (iron and vitamin B12) in maternal anemia and fetal neural tube defects; local or systemic induction of pro-inflammatory cytokines release and oxidative stress in gastrointestinal disorders and pre-eclampsia; cross-reaction between specific anti-H. pylori antibodies and antigens localized in placental tissue and endothelial cells (pre-eclampsia, fetal growth restriction, miscarriage). Since H. pylori infection is most likely acquired before pregnancy, it is widely believed that hormonal and immunological changes occurring during pregnancy could activate latent H. pylori with a negative impact not only on maternal health (nutritional deficiency, organ injury, death), but also on the fetus (insufficient growth, malformation, death) and sometime consequences can be observed later in life. Another important issue addressed by investigators was to determine whether it is possible to transmit H. pylori infection from mother to child and whether maternal anti-H. pylori antibodies could prevent infant’s infection. Studies on novel diagnostic and therapeutic methods for H. pylori are no less important, since these are particularly sensitive topics in pregnancy conditions. It could be interesting to study the possible correlation between H

  5. Membrane-bound ATPase of intact vacuoles and tonoplasts isolated from mature plant tissue

    Energy Technology Data Exchange (ETDEWEB)

    Lin, W.; Wagner, G.J.; Siegelman, H.W.; Hind, G.

    1977-01-01

    Intact vacuoles were isolated from petals of Hippeastrum and Tulipa (Wagner, G. J. and Siegelman, H. W. (1975) Science 190, 1298 to 1299). The ATPase activity of fresh vacuole suspensions was found to be 2 to 3 times that of protoplasts from the same tissue. 70 to 80% of the ATPase activity of intact vacuoles was recovered in tonoplast preparations. The antibiotic Dio-9 at 6 ..mu..g/10/sup 6/ vacuoles or protoplasts causes 40% inhibition. However, only the protoplast ATPase is sensitive to oligomycin. N,N'-dicyclohexylcarbondiimide (DCCD) slightly stimulates ATPase activity in both vacuole and protoplast suspensions, whereas ethyl-3-(3-dimethylaminopropyl carbodiimide) (EDAC) strongly inhibits. Spectrophotometric studies show that in the petal the vacuolar contents have a pH of 4.0 for Tulipa and 4.3 for Hippeastrum, whereas the intact isolated vacuole has an internal pH of 7.0 (in pH 8.0 buffer) for Tulipa and about 7.3 for Hippeastrum. Internal ion concentrations of 150, 46, 30, 30 and 6 mM were found for K/sup +/, Na/sup +/, Mg/sup 2 +/, Cl/sup -/, and Ca/sup 2 +/ respectively, which are about the same as those in protoplasts.

  6. Design based on Bioinformatics and Expression Optimization of Fusion Protein with Cholera Toxin B Subunit and an Epitope Peptide from Helicobacter pylori Urease A Subunit%幽门螺旋杆菌尿素酶A亚基抗原表位肽与霍乱毒素B 亚基融合蛋白的生物信息学设计及表达优化研究

    Institute of Scientific and Technical Information of China (English)

    郭乐; 刘昆梅; 李小康; 汤锋; 奚涛

    2013-01-01

      幽门螺旋杆菌(Hp)是慢性胃炎、消化性溃疡和胃癌的重要致病因子.研发基于Hp尿素酶的表位疫苗是一种很有前景的防治Hp感染的策略.本研究主要通过生物信息学软件对Hp尿素酶表位肽U21和霍乱毒素B 亚基(CTB)的连接顺序和间隔序列加以分析,设计出一种由U21和CTB构成的Hp表位疫苗CTB-UA.通过基因克隆技术构建含有融合基因CTB-UA的重组表达载体pETCUA及其重组菌株;重组菌株经经蛋白表达和优化后,利用Ni-NTP 镍离子亲和层析和DEAE Sepharose FF阴离子交换层析纯化融合蛋白CTB-UA,获得高纯度(94.8%)的融合蛋白CTB-UA.并进一步通过腹腔注射免疫BALB/ c小鼠,鉴定Hp 表位疫苗CTB-UA 的免疫学活性,经间接ELISA 鉴定小鼠能够产生针对CTB和表位肽U21的高滴度特异性抗体.结果证明,Hp表位疫苗CTB-UA 具有科学合理的结构,能在大肠杆菌表达系统中获得较高水平的表达,且具有较高的免疫学特异性,为研发防治Hp感染的表位疫苗奠定一定的实验基础.%Helicobacter pylori (Hp)is associated with the development of chronic gastritis,peptic ulcer and gastric cancer. Epitope vaccine based on the enzyme urease of Hp is a promising option for prophylactic and therapeutic vaccination against Hp infection. An epitope vaccine CTB-UA composed of cholera toxin B subunit (CTB)and an epitope peptide named U21 from urease A subunit was constructed by analyzing the coupling sequence and linker between CTB and U21 using bioinformatics software. The recombinant expression vector pETCUA containing the fusion gene CTB-UA and its recombinant strain were constructed by gene cloning technology. After protein expression and optimization,the recombinant protein CTB-UA was purified by Ni2 + -charged column chromatography and anion-exchange chromatography using DEAE sepharose FF,about 51 mg of pure target protein was obtained from 1 L of fermentation broth and the purity of CTB

  7. Campylobacter pylori: clinical, histological, and serological studies.

    Science.gov (United States)

    Musgrove, C; Bolton, F J; Krypczyk, A M; Temperley, J M; Cairns, S A; Owen, W G; Hutchinson, D N

    1988-01-01

    The presence of Campylobacter pylori, histologically diagnosed gastritis, and antibodies to C pylori were determined in a series of 113 patients undergoing endoscopy. Paired biopsy specimens from the fundus, body, and antrum were collected from 59 patients and from the antrum of 54 patients. The presence of C pylori was confirmed by either culture or silver stain in 30 of 59, 31 of 59, and 54 of 103 biopsy specimens from the fundus, body, and antrum, respectively. Of the specimens which contained C pylori 20 of 30 (66%) from the fundus, 25 of 31 (80%) from the body, and 54 (100%) from the antrum showed gastritis. C pylori and gastritis were shown in seven of nine (78.1%) of patients with gastric ulcers and in nine of 11 (82%) of patients with duodenal ulcers. Using an enzyme linked immunosorbent assay (ELISA) technique to detect IgG antibody to C pylori, all patients with histologically diagnosed gastritis and organisms present had titres of greater than or equal to 640; eight of 39 (21%) of patients without gastritis and without organisms gave similar titres. Hence the presence of C pylori was associated with gastritis and with raised titres of IgG antibody. Images Fig 1 Fig 2 PMID:3225334

  8. Hematologic manifestations of Helicobacter pylori infection

    Science.gov (United States)

    Campuzano-Maya, Germán

    2014-01-01

    Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B12 (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases. PMID:25278680

  9. Study of serum Helicobacter pylori soluble antigen

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 朱永良

    2002-01-01

    Objective:to explore a new serological method for detecting Helicobacter pylori(H.pylori) infection.Methods:Serum soluble antigen of H.pylori was detected by using avidin-biotin ELISA technique to evaluate the status of H.pylori infection and for comparison with rapid urease test(RUT).histologic examination and serology,Results:The sensitivity,specificity,positive predictive value and negative predictive value were 77.46% ,91.07%,91.67% and 76.12%,respectively.The prevalence rate of werum H. pylori soluble antigen in 138 patients undergong endoscopy was similar to the rate obtained by 14 C-UBT methods(P>0.05).Conclusions:The detection of serum H.pylori soluble antigen(HpSAg) could be used as a new serological method which is accurate,and convenient,not affected by the memorizing raction of serum antibody;is more sensitive,more specific and suitable for dinical diagriosis,and evaluation of eradication and for follow-up of H.pylori as well as for detection in children and pregnant women.

  10. Th immune response induced by H pylori vaccine with chitosan as adjuvant and its relation to immune protection

    Institute of Scientific and Technical Information of China (English)

    Yong Xie; Nan-Jin Zhou; Yan-Feng Gong; Xiao-Jiang Zhou; Jiang Chen; Si-Juan Hu; Nong-Hua Lu; Xiao-Hua Hou

    2007-01-01

    AIM: To study the immunological protective effect of H pylori vaccine with chitosan as an adjuvant and its mechanism.METHODS: Female BALB/c mice were randomly divided into seven groups and orally immunized respectively with PBS, chitosan solution, chitosan particles, H pylori antigen, H pylori antigen plus cholera toxin (CT), H pylori antigen plus chitosan solution, H pylori antigen plus chitosan particles once a week for four weeks. Four weeks after the last immunization, the mice were challenged twice by alive H pylori (1 × 109 CFU/mL) and sacrificed. Part of the gastric mucosa was embedded in paraffin, cut into sections and assayed with Giemsa staining. Part of the gastric mucosa was used to quantitatively culture H pylori. ELISA was used to detect cytokine level in gastric mucosa and anti- H pylori IgGl, IgG2a levels in serum.RESULTS: In the groups with chitosan as an adjuvant, immunological protection was achieved in 60% mice, which was significantly higher than in groups with H pylori antigen alone and without H pylori antigen (P < 0.05 or 0.001). Before challenge, the level of IFN and IL-12 in gastric mucosa was significantly higher in the groups with chitosan as an adjuvant than in the control group and the group without adjuvant (P < 0.05 or 0.005). After challenge, the level of IFN and IL-12 was significantly higher in the groups with adjuvant than in the groups without adjuvant and antigen (P < 0.05 or 0.001). Before challenge, the level of IL-2 in gastric mucosa was not different among different groups. Afterchallenge the level of IL-2 was significantly higher in the groups with adjuvant than in the control group (P < 0.05 or 0.001). Before challenge, the level of IL-10 in gastric mucosa was significantly higher in the groups with chitosan as an adjuvant than in other groups without adjuvant (P < 0.05 or 0.01). After challenge, the level of IL-10 was not different among different groups. Before challenge, the level of IL-4 in gastric mucosa

  11. STUDY OF THE DYNAMIC OF HELICOBACTER PYLORI INFECTION PREVALENCE IN DIFFERENT AGE GROUPS OF ST. PETERSBURG POPULATION IN 2007-2011

    OpenAIRE

    A. V. Svarval; R. S. Ferman; A. B. Zhebrun

    2012-01-01

    Abstract. Presence of specific antibodies to H. pylori and to its Cag A toxin was studied in 1917 persons, including 860 children and 1057 adults, in Pasteur Research Institute of Epidemiology and Microbiology, St. Petersburg, Russia. The studied group was presented by the subjectively healthy individuals and blood donors living in St. Petersburg. The growth and stabilization of serological positive rates to H. pilory at high level, as well as increasing the proportion of CagA-positive infect...

  12. Targeted Silencing of Anthrax Toxin Receptors Protects against Anthrax Toxins*

    Science.gov (United States)

    Arévalo, Maria T.; Navarro, Ashley; Arico, Chenoa D.; Li, Junwei; Alkhatib, Omar; Chen, Shan; Diaz-Arévalo, Diana; Zeng, Mingtao

    2014-01-01

    Anthrax spores can be aerosolized and dispersed as a bioweapon. Current postexposure treatments are inadequate at later stages of infection, when high levels of anthrax toxins are present. Anthrax toxins enter cells via two identified anthrax toxin receptors: tumor endothelial marker 8 (TEM8) and capillary morphogenesis protein 2 (CMG2). We hypothesized that host cells would be protected from anthrax toxins if anthrax toxin receptor expression was effectively silenced using RNA interference (RNAi) technology. Thus, anthrax toxin receptors in mouse and human macrophages were silenced using targeted siRNAs or blocked with specific antibody prior to challenge with anthrax lethal toxin. Viability assays were used to assess protection in macrophages treated with specific siRNA or antibody as compared with untreated cells. Silencing CMG2 using targeted siRNAs provided almost complete protection against anthrax lethal toxin-induced cytotoxicity and death in murine and human macrophages. The same results were obtained by prebinding cells with specific antibody prior to treatment with anthrax lethal toxin. In addition, TEM8-targeted siRNAs also offered significant protection against lethal toxin in human macrophage-like cells. Furthermore, silencing CMG2, TEM8, or both receptors in combination was also protective against MEK2 cleavage by lethal toxin or adenylyl cyclase activity by edema toxin in human kidney cells. Thus, anthrax toxin receptor-targeted RNAi has the potential to be developed as a life-saving, postexposure therapy against anthrax. PMID:24742682

  13. Endoplasmic reticulum stress contributes to Helicobacter pylori VacA-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Yuko Akazawa

    Full Text Available Vacuolating cytotoxin A (VacA is one of the important virulence factors produced by H. pylori. VacA induces apoptotic cell death, which is potentiated by ammonia. VacA also causes cell death by mitochondrial damage, via signaling pathways that are not fully defined. Our aim was to determine whether endoplasmic reticulum (ER stress is associated with VacA-induced mitochondrial dysfunction and apoptosis. We found that C/EBP homologous protein (CHOP, a key signaling protein of ER stress-induced apoptosis, was transcriptionally up-regulated following incubation of gastric epithelial cells with VacA. The effect of VacA on CHOP induction was significantly enhanced by co-incubation with ammonium chloride. Phosphorylation of eukaryotic initiation factor 2 (eIF2-alpha, which is known to occur downstream of the ER stress sensor PKR-like ER-localized eIF2-alpha kinase (PERK and to regulate CHOP expression, was also observed following incubation with VacA in the presence of ammonium chloride. Knockdown of CHOP by siRNA resulted in inhibition of VacA-induced apoptosis. Further studies showed that silencing of the PERK gene with siRNA attenuated VacA-mediated phosphorylation of eIF2-alpha, CHOP induction, expression of BH3-only protein Bim and Bax activation, and cell death induced by VacA with ammonium chloride, indicating that ER stress may lead to mitochondrial dysfunction during VacA-induced toxicity. Activation of ER stress and up-regulation of BH3-only proteins were also observed in human H. pylori-infected gastric mucosa. Collectively, this study reveals a possible association between VacA-induced apoptosis in gastric epithelial cells, and activation of ER stress in H. pylori-positive gastric mucosa.

  14. Adherence of Helicobacter pylori to the Gastric Mucosa

    Directory of Open Access Journals (Sweden)

    Marguerite Clyne

    1997-01-01

    Full Text Available Bacterial adhesion to the intestinal epithelium is a critical initial step in the pathogenesis of many enteric diseases. Helicobacter pylori is a duodenal pathogen that adheres to the gastric epithelium and causes gastritis and peptic ulceration. The mechanism by which H pylori causes disease has not yet been elucidated but adherence to the gastric mucosa is thought to be an important virulence determinant of the organism. What is known about adherence of H pylori to the gastric mucosa is summarized. Topics discussed are the mechanism of H pylori adherence; in vitro and in vivo models of H pylori infection; and adherence and potential adhesins and receptors for H pylori.

  15. Novel Structure and Function of Typhoid Toxin

    Science.gov (United States)

    ... Matters NIH Research Matters July 29, 2013 Novel Structure and Function of Typhoid Toxin Structure of typhoid toxin, showing the 2 A subunits ( ... to cultured cells. The scientists next determined the structure of the typhoid toxin. The toxin was already ...

  16. Botulinum Toxin (Botox) for Facial Wrinkles

    Science.gov (United States)

    ... Stories Español Eye Health / Eye Health A-Z Botulinum Toxin (Botox) for Facial Wrinkles Sections Botulinum Toxin (Botox) ... Facial Wrinkles How Does Botulinum Toxin (Botox) Work? Botulinum Toxin (Botox) for Facial Wrinkles Written by: Kierstan Boyd ...

  17. Ultrastructural and autoradiographic studies of the role of nucleolar vacuoles in soybean root meristem.

    Directory of Open Access Journals (Sweden)

    Dariusz Stepiński

    2004-03-01

    Full Text Available Ultrastructural and autoradiographic studies of nucleoli in soybean root meristematic cells in seedlings: (1 grown for 3 days at 25 degrees C (control, (2 grown for three days at 25 degrees C and for 4 days at 10 degrees C, and (3 grown as in (2 and recovered for 1 day at 25 degrees C were carried out. Control nucleoli had dense structure and a few small nucleolar vacuoles. Chilled plant nucleoli had less dense structure and no vacuoles. Nucleoli of plants recovered at 25 degrees C had big nucleolar vacuoles. In autoradiograms of squashed preparations, the labeling of nucleoli and cytoplasm after 20-min incubation in 3H-uridine was 5- and 6-fold stronger, respectively, in control than in chilled roots. Following recovery, the labeling of nucleoli and cytoplasm was much stronger than after chilling or even than in control roots. After 80-min postincubation in non-radioactive medium, average labeling of particular areas of cells was the highest in recovered plants which indicated intensification of rRNA synthesis, maturation and transport into cytoplasm resulting from the resumption of optimal conditions which was correlated with the appearance of big nucleolar vacuoles. In autoradiograms of semi-thin sections from roots of seedlings chilled for 4 days then recovered and incubated for 20 min in 3H-uridine, practically only extravacuolar parts of nucleoli were labeled. After 80-min postincubation, the labeling of nucleolar vacuoles was observed. Thus, during postincubation the labeled molecules were translocated from the nucleolar periphery into nucleolar vacuoles in cells where intensive transport of these molecules to the cytoplasm takes place. On the basis of these results, a hypothesis has been put forward that nucleolar vacuoles may be involved in the intensification of pre-ribosome transport outside nucleolus.

  18. Helicobacter pylori: focus on CagA and VacA major virulence factors Helicobacter pylori: enfoque sobre los factores de virulencia CagA y VacA

    Directory of Open Access Journals (Sweden)

    Gonzalo Castillo-Rojas

    2004-12-01

    Full Text Available After colonizing the human gastric mucosa, Helicobacter pylori can remain within the host for years and even decades, and is associated with several, highly significant gastric pathologies. In Mexico, the seroprevalence at 1 year of age is 20% and the estimated increment in seropositivity per year is 5% for children aged 1-10 years. More than 80% of adults are infected by the time they are 18-20 years old. Bacterial virulence factors have been proposed for H. pylori, such as urease, flagella, heat-shock protein, lipopolysaccharide, adhesions, vacuolating cytotoxin, cag pathogenicity island and the cytotoxin-associated protein, the latter being the most studied mechanism to date.Después de colonizar la mucosa gástrica humana, Helicobacter pylori puede permanecer por años e incluso décadas en el humano, y se asocia a varias patologías gástricas. En México, la seroprevalencia estimada es de 20% en niños de un año de edad, con una tasa de incremento en seropositividad de 5% anual durante los primeros 10 años de vida hasta alcanzar 80% en adultos jóvenes entre los 18 y 20 años de edad. Los factores bacterianos de virulencia propuestos para H. pylori son ureasa, flagelos, proteínas de choque térmico, lipopolisacárido, adhesinas, citotoxina vacuolizante, isla de patogenicidad y la proteína asociada a la citoxina; este último factor es el más estudiado hasta la fecha.

  19. Prevalence of vacA, cagA and babA2 genes in Cuban Helicobacter pylori isolates

    Institute of Scientific and Technical Information of China (English)

    Lino E Torres; Karelia Melián; Arlenis Moreno; Jordis Alonso; Carlos A Sabatier; Mayrín Hernández; Ludisleydis Bermúdez; Boris L Rodríguez

    2009-01-01

    AIM: To investigate the prevalence of vacuolating cytotoxin ( vacA), cytotoxin associated gene A ( cagA) and blood adhesion binding antigen ( babA2) genotypes of Helicobacter pylori ( H pylori) isolates from Cuban dyspeptic patients. METHODS: DNA was extracted from H pylori-positive cultures taken from 130 dyspeptic patients. Genotyping was performed by PCR, using specific primers for vacA ( s1, s2, m1, m2), cagA and babA2 genes. Endoscopic observations and histological examinations were used to determine patient pathologies. RESULTS: vacA alleles s1, s2, m1 and m2 were detected in 96 (73.8%), 34 (26.2%), 75 (57.7%) and 52 isolates (40%), respectively, while the cagA gene was detected in 95 isolates (73.2%). One hundred and seven isolates (82.3%) were babA2-positive. A significant correlation was observed between vacAs1m1 and cagA and between vacAs1m1 and babA2 genotypes ( P < 0.001 and P < 0.05, respectively) and between babA2 genotype and cagA status ( P < 0.05); but, no correlation was observed between vacAs1 and babA2 genotypes. Eighty five (65.4%) and 73 (56.2%) strains were type 1 ( vacAs1- cagA-positive) and "triplepositive" ( vacAs1- cagA- babA2-positive), respectively, and their presence was significantly associated with duodenal ulcer ( P < 0.01 and P < 0.001, respectively). CONCLUSION: The distribution of the main virulence factors in the Cuban strains in this study resembled that of the Western-type strains, and the more virulent H pylori isolates were significantly associated with duodenal ulcer, ulcer disease being the worst pathology observed in the group studied.

  20. Helicobacter pylori infection in patients with autoimmune thrombocytopenic purpura

    Institute of Scientific and Technical Information of China (English)

    Erdal Kurtoglu; Ertugrul Kayacetin; Aysegul Ugur

    2004-01-01

    AIM: To compare the prevalence of Helicobacter pylori (Hpylori) infection in autoimmune thrombocytopenic purpura (AITP) patients with that of nonthrombocytopenic controls,and to evaluate the efficacy of the treatment in H pylori(+)and H pylori(-) AITP patients.METHODS: The prevalence of gastric H pylori infection in 38 adult AITP patients (29 female and 9 male; median age 27 years; range 18-39 years) who consecutively admitted to our clinic was investagated.RESULTS: H pylori infection was found in 26 of 38 AITP patients (68.5%). H pylori infection was found in 15 of 23control subjects (65.2%). The difference in H pylori infection between the 2 groups was not significant. Thrombocyte count of H pylori-positive AITP patients was significantly lower than that of H pylori-negative AITP patients (P<0.05).Thrombocyte recovery of H pylori-positive group was less than that of H pylori-negative group (P<0.05).CONCLUSION: H pylori infection should be considerecd in the treatment of AITP patients with H pylori infection.

  1. Eradication of Helicobacter pylori infection.

    Science.gov (United States)

    Wu, Tzung-Shiun; Hu, Huang-Ming; Kuo, Fu-Chen; Kuo, Chao-Hung

    2014-04-01

    Eradication of Helicobacter pylori infection has become an important issue recently, because this bacterial species cluster can cause many gastrointestinal diseases. Elevated antibiotic resistance is related to an increasing failure rate of H. pylori eradication. Standard triple therapy is still the first-line therapy; however, according to the Maastricht IV Consensus Report, it should be abandoned in areas of high clarithromycin resistance. Alternative first-line therapies include bismuth-containing quadruple therapy, sequential, concomitant, and hybrid therapies. Quinolone-based triple therapy may be considered as first-line therapy in areas of clarithromycin resistance >15-20% and quinolone resistance <10%. Unique second-line therapy is still unclear, and bismuth-containing quadruple therapy or levofloxacin-based triple therapy can be used as rescue treatment. Third-line therapy should be under culture guidance to select the most effective regimens (such as levofloxacin-based, rifabutin-based, or furazolidone-based therapies). Antibiotics resistance, patient compliance, and CYP 2C19 genotypes could influence the outcome. Clinicians should use antibiotics according to local reports.

  2. Treatment of Helicobacter pylori infection.

    LENUS (Irish Health Repository)

    O'Connor, Anthony

    2012-02-01

    This article aims to examine current best practice in the field reference to first-line, second-line, rescue and emerging treatment regimens for Helicobacter pylori eradication. The recommended first-line treatment in published guidelines in Europe and North American is proton pump inhibitor combined with amoxicillin and clarithromycin being the favoured regimen. Rates of eradication with this regimen however are falling alarmingly due to a combination of antibiotic resistance and poor compliance with therapy. Bismuth based quadruple therapies and levofloxacin based regimes have been shown to be effective second line regimens. Third-line options include regimes based on rifabutin or furazolidone, but susceptibility testing is the most rational option here, but is currently not used widely enough. Sequential therapy is promising but needs further study and validation outside of Italy. Although the success of first line treatments is falling, if compliance is good and a clear treatment paradigm adhered to, almost universal eradication rates can still be achieved. If compliance is not achievable, the problem of antibiotic resistance will continue to beset any combination of drugs used for H. pylori eradication.

  3. Transmission of Helicobacter pylori Infection

    Directory of Open Access Journals (Sweden)

    Giuseppina Oderda

    1999-01-01

    Full Text Available Helicobacter pylori infection is one of the most common bacterial infections worldwide. It is accepted as the major cause of chronic gastritis, peptic ulcer, carcinoma of the distal part of the stomach and gastric lymphoma. However, how and when the infection is acquired remain largely unknown. Identification of mode of transmission is vital for developing preventive measures to interrupt its spread, but studies focused on this issue are difficult to implement. From epidemiological studies, it is known that there are great differences in the prevalence of infection in different populations and in ethnic groups originating from high prevalence regions. This is likely related to inferior hygienic conditions and sanitation. In developing countries, infection occurs at a much earlier age. In developed countries, the prevalence of infection is related to poor socioeconomic conditions, particularly density of living. Humans seem to be the only reservoir of H pylori, which spread from person to person by oral-oral, fecal-oral or gastro-oral routes. Most infections are acquired in childhood, possibly from parents or other children living as close contacts. Infection from the environment or from animals cannot be entirely excluded.

  4. Prevalence of Helicobacter Pylori Infection Among Patients ...

    African Journals Online (AJOL)

    variables such as age, sex, socioeconomic status, dietary habits, genetic, and immunological ... Age distribution of H. pylori infection did not show any trend towards increase or .... infection in dyspeptic patients in Iran. Gastroenterol Insights.

  5. Helicobacter Pylori Bacteremia: An Unusual Finding

    Science.gov (United States)

    De Luca, Concetta; Mancin, Annalisa; Calabrò, Maria; Daleno, Cristina; Ferrario, Antonella; Renzulli, Raffaella; Scuderi, Cristina; Casari, Erminia

    2016-01-01

    We report a case of Helicobacter pylori transient bacteremia in a woman with ulcerated antral gastric cancer. The patient was hospitalized for laparoscopy and subtotal gastrectomy. After surgery she developed fever (39°C) and was empirically treated with levofloxacin. Blood cultures, collected and sent immediately to Laboratory, were positive for a spiral Gram-negative bacterium. This isolate was identified as H. pylori and the specific susceptibility test was performed. One day after the fever was decreased but antibiotic treatment with levofloxacin was continued and it was maintained until discharge. In summary, H. pylori transient bacteremia may occur as a rare complication after stomach surgery. Further studies are necessary to elucidate the potential role of Helicobacter pylori presence in blood.

  6. Helicobacter pylori: Basic Mechanisms to Clinical Cure

    Directory of Open Access Journals (Sweden)

    ABR Thomson

    1995-01-01

    Full Text Available Since its rediscovery 10 years ago, Helicobacter pylori has reshaped our thinking about the course of peptic ulcer disease. Our approach to the patient with a duodenal ulcer has become one of attempting eradication therapy at the time of first diagnosis, in the hope of curing the ulcer disease. Gastric and duodenal ulceration are only two of the manifestations of this chronic antral infection; other complications of H pylori include gastritis, gastric cancer and possible maltomas. Therapy of H pylori infection is complicated and involves dual therapy with an antibiotic plus a protein pump inhibitor, such as omeprazole 20 mg bid plus amoxicillin 1 g bid for two weeks, triple or quadruple therapy with bismuth, two antibiotics and an H2-receptor antagonist. Vaccination against H pylori is on the far horizon.

  7. Epidemiology and Diagnosis of Helicobacter pylori infection.

    Science.gov (United States)

    Mentis, Andreas; Lehours, Philippe; Mégraud, Francis

    2015-09-01

    During the period reviewed, prevalence studies were essentially performed in less economically advanced countries and a high prevalence was found. The traditional risk factors for Helicobacter pylori positivity were mostly found. Transmission studied by molecular typing showed a familial transmission. The eventual role of water transmission was explored in several studies with controversial results. Concerning diagnosis, most of the invasive and noninvasive methods used for the diagnosis of H. pylori infection are long standing with efficient performance. The most interesting recent improvements in H. pylori diagnosis include advances in endoscopy, developments in molecular methods, and the introduction of omics-based techniques. Interpretation of old or newer method should take into account the pretest probability and the prevalence of H. pylori in the population under investigation. © 2015 John Wiley & Sons Ltd.

  8. Relationship between helicobacter pylori infection and endoscopic ...

    African Journals Online (AJOL)

    Relationship between helicobacter pylori infection and endoscopic findings among patients with dyspepsia in north ... Sudan Journal of Medical Sciences ... Results: Of the 148 subjects studied, 68 (46.0%) were males and 80 (54.0%) females.

  9. Distribution of Helicobacter pylori in north China

    Institute of Scientific and Technical Information of China (English)

    Yue-Hua Gong; Ying Wang; Yuan Yuan

    2005-01-01

    AIM: To compare the distribution of virulence-associatedgenotypes of Helicobacter pylori(H pylori) in two areas of north China with different gastric cancer risk and furthermore probe into the pathogenicity of the bacterium. METHODS: Gastric biopsies were taken from 355 subjects from Zhuanghe, a high risk area of gastric cancer, and 136 subjects from Shenyang, a low risk area of gastric cancer. A total of 149 H pylori strains isolated from these patients were studied by PCR for differences in the genotypes of cagA, vac A, and iceA.RESULTS: In patients with high risk for gastric cancer, higher frequencies of vacA s1 or s1m1b genotypes were found as compared to those from the low risk area. CONCLUSION: There is significantly different distribution of H pylori genotypes between Zhuanghe and Shenyang areas in north China.

  10. HELICOBACTER PYLORI: THE CAUSATIVE AGENT OF PEPTIC ...

    African Journals Online (AJOL)

    DR. AMINU

    some of the virulence factors possessed by the organism, its metabolism and growth .... lymphoma and some types of gastric adenocarcinoma .... carbon to the lungs, where the patient exhales it. .... pylori as a risk factor for cancer, Bailliere's.

  11. [Toxins as a biological weapon].

    Science.gov (United States)

    Płusa, Tadeusz

    2015-09-01

    The criteria for recognizing a chemical compound for the toxin are vague and gave it the possibility of inclusion in this group a number of biological agents. Toxins list is extensive, but the interest is focused on bacterial toxins, poisons derived from snake venoms, algae and plant proteins, and small molecules. Particular attention is focused on the so-called "sea" toxins, which include tetrodotoxin, brevetoxin and saxitoxin. This indicates the search for a new hitherto unknown potential bioterrorist threats. © 2015 MEDPRESS.

  12. Burkholderia cepacia complex isolates survive intracellularly without replication within acidic vacuoles of Acanthamoeba polyphaga.

    Science.gov (United States)

    Lamothe, Julie; Thyssen, Sandra; Valvano, Miguel A

    2004-12-01

    We have previously demonstrated that isolates of the Burkholderia cepacia complex can survive intracellularly in murine macrophages and in free-living Acanthamoeba. In this work, we show that the clinical isolates B. vietnamiensis strain CEP040 and B. cenocepacia H111 survived but did not replicate within vacuoles of A. polyphaga. B. cepacia-containing vacuoles accumulated the fluid phase marker Lysosensor Blue and displayed strong blue fluorescence, indicating that they had low pH. In contrast, the majority of intracellular bacteria within amoebae treated with the V-ATPse inhibitor bafilomycin A1 localized in vacuoles that did not fluoresce with Lysosensor Blue. Experiments using bacteria fluorescently labelled with chloromethylfluorescein diacetate demonstrated that intracellular bacteria remained viable for at least 24 h. In contrast, Escherichia coli did not survive within amoebae after 2 h post infection. Furthermore, intracellular B. vietnamiensis CEP040 retained green fluorescent protein within the bacterial cytoplasm, while this protein rapidly escaped from the cytosol of phagocytized heat-killed bacteria into the vacuolar lumen. Transmission electron microscopy analysis confirmed that intracellular Burkholderia cells were structurally intact. In addition, both Legionella pneumophila- and B. vietnamiensis-containing vacuoles did not accumulate cationized ferritin, a compound that localizes within the lysosome. Thus, our observations support the notion that B. cepacia complex isolates can use amoebae as a reservoir in the environment by surviving without intracellular replication within an acidic vacuole that is distinct from the lysosomal compartment.

  13. Identification of a Peptide-Pheromone that Enhances Listeria monocytogenes Escape from Host Cell Vacuoles

    Science.gov (United States)

    Xayarath, Bobbi; Alonzo, Francis; Freitag, Nancy E.

    2015-01-01

    Listeria monocytogenes is a Gram-positive facultative intracellular bacterial pathogen that invades mammalian cells and escapes from membrane-bound vacuoles to replicate within the host cell cytosol. Gene products required for intracellular bacterial growth and bacterial spread to adjacent cells are regulated by a transcriptional activator known as PrfA. PrfA becomes activated following L. monocytogenes entry into host cells, however the signal that stimulates PrfA activation has not yet been defined. Here we provide evidence for L. monocytogenes secretion of a small peptide pheromone, pPplA, which enhances the escape of L. monocytogenes from host cell vacuoles and may facilitate PrfA activation. The pPplA pheromone is generated via the proteolytic processing of the PplA lipoprotein secretion signal peptide. While the PplA lipoprotein is dispensable for pathogenesis, bacteria lacking the pPplA pheromone are significantly attenuated for virulence in mice and have a reduced efficiency of bacterial escape from the vacuoles of nonprofessional phagocytic cells. Mutational activation of PrfA restores virulence and eliminates the need for pPplA-dependent signaling. Experimental evidence suggests that the pPplA peptide may help signal to L. monocytogenes its presence within the confines of the host cell vacuole, stimulating the expression of gene products that contribute to vacuole escape and facilitating PrfA activation to promote bacterial growth within the cytosol. PMID:25822753

  14. Effectiveness of Citrus Fruits on Helicobacter pylori

    Science.gov (United States)

    2017-01-01

    It is known that Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer, and gastric carcinoma. Due to the increased side effects of the treatment regimens and the development of antimicrobial resistance, a number of natural compounds have been tested as potential alternatives. In this review, we will examine the current knowledge on the effect of Citrus fruits and their derivatives against H. pylori, highlighting the remaining outstanding questions on the development of novel therapeutic strategies. PMID:28408943

  15. Helicobacter pylori : migrations humaines et cancer gastrique

    OpenAIRE

    Breurec, Sébastien

    2011-01-01

    Helicobacter pylori is associated with severe gastroduodenal disorders but is also a bacterial genetic marker of human migrations. First, we provide evidence that distinct H. pylori genetic populations accompanied at least four ancient human migrations into Oceania and Southeast Asia: i) an expansion of Austronesian speaking people about 5000 years ago from Taiwan into Oceania, ii) a migration from India into Southeast Asia within the last 2000 years, iii) a migration of Austro-Asiatic speaki...

  16. Detection of Helicobacter pylori in Oral Lesions

    OpenAIRE

    Irani, Soussan; Monsef Esfahani, Alireza; Bidari Zerehpoush, Farahnaz

    2013-01-01

    Background and aims. Helicobacter pylori is a microaerophilic gram-negative spiral organism. It is recognized as the etiologic factor for peptic ulcers, gastric adenocarcinoma and gastric lymphoma. Recently, it has been isolated from dental plaque and the dorsum of the tongue. This study was designed to assess the association between H. pylori and oral lesions such as ulcerative/inflammatory lesions, squamous cell carcinoma (SCC) and primary lymphoma. Materials and methods. A total of 228 bio...

  17. LYSOSOMAL DISRUPTION BY BACTERIAL TOXINS

    Science.gov (United States)

    Bernheimer, Alan W.; Schwartz, Lois L.

    1964-01-01

    Bernheimer, Alan W. (New York University School of Medicine, New York), and Lois L. Schwartz. Lysosomal disruption by bacterial toxins. J. Bacteriol. 87:1100–1104. 1964.—Seventeen bacterial toxins were examined for capacity (i) to disrupt rabbit leukocyte lysosomes as indicated by decrease in turbidity of lysosomal suspensions, and (ii) to alter rabbit liver lysosomes as measured by release of β-glucuronidase and acid phosphatase. Staphylococcal α-toxin, Clostridium perfringens α-toxin, and streptolysins O and S affected lysosomes in both systems. Staphylococcal β-toxin, leucocidin and enterotoxin, Shiga neurotoxin, Serratia endotoxin, diphtheria toxin, tetanus neurotoxin, C. botulinum type A toxin, and C. perfringens ε-toxin were not active in either system. Staphylococcal δ-toxin, C. histolyticum collagenase, crude C. perfringens β-toxin, and crude anthrax toxin caused lysosomal damage in only one of the test systems. There is a substantial correlation between the hemolytic property of a toxin and its capacity to disrupt lysosomes, lending support to the concept that erythrocytes and lysosomes are bounded by similar membranes. PMID:5874534

  18. Molecular characterization of Helicobacter pylori VacA induction of IL-8 in U937 cells reveals a prominent role for p38MAPK in activating transcription factor-2, cAMP response element binding protein, and NF-kappaB activation

    DEFF Research Database (Denmark)

    Hisatsune, Junzo; Nakayama, Masaaki; Isomoto, Hajime;

    2008-01-01

    Helicobacter pylori VacA induces multiple effects on susceptible cells, including vacuolation, mitochondrial damage, inhibition of cell growth, and enhanced cyclooxygenase-2 expression. To assess the ability of H. pylori to modulate the production of inflammatory mediators, we examined the mechan......Helicobacter pylori VacA induces multiple effects on susceptible cells, including vacuolation, mitochondrial damage, inhibition of cell growth, and enhanced cyclooxygenase-2 expression. To assess the ability of H. pylori to modulate the production of inflammatory mediators, we examined...... the mechanisms by which VacA enhanced IL-8 production by promonocytic U937 cells, which demonstrated the greatest VacA-induced IL-8 release of the cells tested. Inhibitors of p38 MAPK (SB203580), ERK1/2 (PD98059), IkappaBalpha ((E)-3-(4-methylphenylsulfonyl)-2-propenenitrile), Ca(2+) entry (SKF96365......+) in mediating activation of MAPK and the canonical NF-kappaB pathway. VacA stimulated translocation of NF-kappaBp65 to the nucleus, consistent with enhancement of IL-8 expression by activation of the NF-kappaB pathway. In addition, small interfering RNA of activating transcription factor (ATF)-2 or CREB, which...

  19. Changing epidemiology of Helicobacter pylori in Japan.

    Science.gov (United States)

    Inoue, Manami

    2017-03-01

    Helicobacter pylori (H. Pylori) is known as the most important cause of gastric cancer. The prevalence of H. pylori infection varies widely by geographic area, age, and socioeconomic status. In Japan, H. pylori infection has been highly correlated with the incidence rate of gastric cancer, and a reduction in H. pylori infection is therefore crucial for decreasing the incidence of gastric cancer, especially at the population level. Infection occurs during childhood, commonly before 5 years of age. In Japan, where gastric cancer has ranked as the most common cancer by incidence and mortality for the last several decades, the prevalence of H. pylori infection has dramatically declined by birth cohort effect, mainly due to improvements in the general hygiene environment in childhood. Older generations born before around 1950 show a high prevalence of around 80-90 %, decreasing with age to reach around 10 % or less in those born around the 1990s, and less than 2 % for children born after the year 2000. This change will have generational effects on gastric cancer prevention strategies, both primary and secondary. The risk-stratified approach to gastric cancer prevention should be considered in Japan and other countries which have similarly experienced rapid economic development.

  20. Relation between Psoriasis and Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Dursun Türkmen

    2011-06-01

    Full Text Available Objective: Psoriasis is a common, chronic, inflammatory and hyperproliferative skin disease. It was aimed to detect the role of H. pylori in triggering psoriasis. Materials and Methods: A total of 56 clinically diagnosed psoriatic patients who applied to the dermatology outpatient clinic, were included in the study. As the control group, 57 patients who do not have psoriasis and H. pylori associated dermatologic diseases were included in the study. All patients and control group were tested for H. pylori by the urea-breath test (UBT. Results: Thirty-eight (67.9% of 56 psoriasis patients (mean age 38.4±14.08 years; 32 men, 24 women and 38 (66.7% of 57 control group(men age, 37.9±13.73 years; 26 men, 31 women were positive for H. pylori. There was no statistically significant difference between psoriasis patients and controls with respect to the urea breath test (p=0.89. UBT was positive in all patiens who have gastrointestinal reflux. Conclusion: We could not determine the role of H. pylori in psoriasis. There have been some reports about the association of H. pylori and palmoplantar pustular psoriasis. Therefore, we believe that there is a need for newer studies in a large psoriasis group with tests which have higher specificity and sensitivity.

  1. Study of serum Helicobacter pylori soluble antigen

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 朱永良

    2002-01-01

    Objective: to explore a new serological method for detecting Helicobac ter pylori ( H. pylori ) infection. Methods: Serum soluble antigen of H. p ylor i was detected by using avidin-biotin ELISA technique to evaluate the status of H. pylori infection and for comparison with rapid urease test ( RUT ), histo logi c examination and serology. Results: The sensitivity, specificity, positive pred ictive value and negative predictive value were 77.46%, 91.07%, 91.67% a nd 76.12 %, respectively. The prevalence rate of serum H. pylori soluble antigen in 138 patients undergoing endoscopy was similar to the rate obtained by 14 C-UBT met hods ( P>0.05 ). Conclusions: The detection of serum H. pylori solub le antigen( HpSAg) could be used as a new serological method which is accurate, and convenie nt, not affected by the memorizing reaction of serum antibody; is more sensitive , m ore specific and suitable for clinical diagnosis, and evaluation of eradication and for follow-up of H. pylori as well as for detection in children and pre gnant women.

  2. Review: clinical management of Helicobacter pylori infection in China.

    Science.gov (United States)

    Xie, Chuan; Lu, Nong-Hua

    2015-02-01

    Helicobacter pylori (H. pylori) infection has been associated with gastric disorders. The situation of H. pylori infection in China-where a high prevalence of H. pylori infection, a high incidence of gastric cancer, and widespread resistance to clarithromycin, metronidazole, and levofloxacin exist-is quite different from that in Western countries. In order for Chinese clinicians to better manage H. pylori infection, a Chinese Study Group on H. pylori published four consensus reports regarding the management of H. pylori infection in China between 1999 and 2012. The eradication rate with standard triple therapy was pylori in China in recent years. © 2014 John Wiley & Sons Ltd.

  3. II Consenso Brasileiro sobre Helicobacter pylori Second Brazilian Consensus Conference on Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Vaz Coelho

    2005-06-01

    Full Text Available Avanços significativos ocorridos desde o Primeiro Consenso Brasileiro sobre H. pylori realizado em 1995, em Belo Horizonte, MG, justificam este segundo consenso. O evento foi organizado pela Federação Brasileira de Gastroenterologia e pelo Núcleo Brasileiro para Estudo do Helicobacter, sendo realizado em São Paulo nos dias 19 e 20 de junho de 2004. Contou com a participação das principais autoridades nacionais na área, a partir de lista elaborada pelas duas sociedades organizadoras do evento. Assim, participaram 36 delegados provenientes de 15 estados brasileiros, incluindo gastroenterologistas, patologistas, pediatras e microbiologistas. Os participantes foram alocados em um dos cinco sub-temas a serem contemplados no encontro, a saber: Helicobacter pylori e dispepsia funcional; Helicobacter pylori e AINEs; Helicobacter pylori e doença do refluxo gastroesofágico; tratamento Helicobacter pylori e retratamento Helicobacter pylori. Foi adotado como consensual as decisões que atingissem 70% ou mais de concordância entre os participantes. Os resultados foram apresentados em outubro de 2004 durante sessão especial da VI Semana Brasileira do Aparelho Digestivo, realizada em Recife, PE, e esta publicação apresenta o sumário das principais recomendações e conclusões do evento.Significant progress has been obtained since the First Brazilian Consensus Conference on H. pylori Infection held in 1995, in Belo Horizonte, MG, and justify a second meeting to establish updated guidelines on the current management of H. pylori infection. The Second Brazilian Consensus Conference on H. pylori Infection was organized by the Brazilian Federation of Gastroenterology and Brazilian Nucleus for the Study of Helicobacter and took place on June, 19-20, 2004 in São Paulo, SP. Thirty six delegates coming from 15 different Brazilian states including gastroenterologists, pathologists, microbiologists and pediatricians undertook the meeting. The

  4. Disruption of Toxoplasma gondii parasitophorous vacuoles by the mouse p47-resistance GTPases.

    Directory of Open Access Journals (Sweden)

    Sascha Martens

    2005-11-01

    Full Text Available The p47 GTPases are essential for interferon-gamma-induced cell-autonomous immunity against the protozoan parasite, Toxoplasma gondii, in mice, but the mechanism of resistance is poorly understood. We show that the p47 GTPases, including IIGP1, accumulate at vacuoles containing T. gondii. The accumulation is GTP-dependent and requires live parasites. Vacuolar IIGP1 accumulations undergo a maturation-like process accompanied by vesiculation of the parasitophorous vacuole membrane. This culminates in disruption of the parasitophorous vacuole and finally of the parasite itself. Over-expression of IIGP1 leads to accelerated vacuolar disruption whereas a dominant negative form of IIGP1 interferes with interferon-gamma-mediated killing of intracellular parasites. Targeted deletion of the IIGP1 gene results in partial loss of the IFN-gamma-mediated T. gondii growth restriction in mouse astrocytes.

  5. Disruption of Toxoplasma gondii Parasitophorous Vacuoles by the Mouse p47-Resistance GTPases.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available The p47 GTPases are essential for interferon-gamma-induced cell-autonomous immunity against the protozoan parasite, Toxoplasma gondii, in mice, but the mechanism of resistance is poorly understood. We show that the p47 GTPases, including IIGP1, accumulate at vacuoles containing T. gondii. The accumulation is GTP-dependent and requires live parasites. Vacuolar IIGP1 accumulations undergo a maturation-like process accompanied by vesiculation of the parasitophorous vacuole membrane. This culminates in disruption of the parasitophorous vacuole and finally of the parasite itself. Over-expression of IIGP1 leads to accelerated vacuolar disruption whereas a dominant negative form of IIGP1 interferes with interferon-gamma-mediated killing of intracellular parasites. Targeted deletion of the IIGP1 gene results in partial loss of the IFN-gamma-mediated T. gondii growth restriction in mouse astrocytes.

  6. Helicobacter pylori-coccoid forms and biofilm formation

    DEFF Research Database (Denmark)

    Andersen, Leif Percival; Rasmussen, Lone

    2009-01-01

    be detected by PCR in water supplies. There is no substantial evidence for viable H. pylori persisting in water supplies. Epidemiological studies suggest that environmental water is a risk factor for H. pylori infection when compared with tap water, and formation of H. pylori biofilm cannot be excluded....... Helicobacter pylori does not seem to take part in biofilm formation in the oral cavity even though the bacterium may be detected....

  7. Extraintestinal manifestations of Helicobacter pylori: A concise review

    OpenAIRE

    Wong, Frank; Rayner-Hartley, Erin; Byrne, Michael F

    2014-01-01

    Helicobacter pylori (H. pylori) infection has been clearly linked to peptic ulcer disease and some gastrointestinal malignancies. Increasing evidence demonstrates possible associations to disease states in other organ systems, known as the extraintestinal manifestations of H. pylori. Different conditions associated with H. pylori infection include those from hematologic, cardiopulmonary, metabolic, neurologic, and dermatologic systems. The aim of this article is to provide a concise review of...

  8. Association Between Helycobacter Pylori Infection and Pathological Oral Manifestations

    Institute of Scientific and Technical Information of China (English)

    Carini Francesco; Samir Mallat; Cappello Francesco; Zummo Giovani; Jurjus Abdo; Tomasello Giovanni; Leone Angelo; Di Pasquale Roberto; Saniflippo Beatrice; Sinagra Emanuele; Damiani Provvidenza; Rosalyn Jurjus; Alice Gerges-Geagea; Inaya Hajj Hussein

    2016-01-01

    Data from the literature are controversial regarding the presence of Helicobacter pylori (H. pylori) in dental plaque and its association with gastric infection. One of the possible mechanisms suggested for re-infection is the recolonization with H. pylori from dental plaque. The purpose of this review was to determine whether dental plaque, poor oral hygiene, and periodontal disease were risk factors for H. pylori infection.

  9. A study of Helicobacter pylori infection in diabetes mellitus

    OpenAIRE

    Khwaja Saifullah Zafar; Vidyasagar Ram; Manoj Kumar

    2016-01-01

    Background: Helicobacter pylori is the most common bacterial infection in human beings. The aim was to study the association of Helicobacter pylori infection in patients of diabetes mellitus. Design of the study was observational analytic cross sectional study. Methods: A total of 69 subjects were studied. Of these 30 were non diabetics and 39 were diabetics, with disease duration more than 1 year. The serological diagnosis of H. pylori was made by Anti- Helicobacter pylori antibody test....

  10. Association Between Helycobacter Pylori Infection and Pathological Oral Manifestations

    Directory of Open Access Journals (Sweden)

    Carini Francesco

    2016-03-01

    Full Text Available Data from the literature are controversial regarding the presence of Helicobacter pylori (H. pylori in dental plaque and its association with gastric infection. One of the possible mechanisms suggested for re-infection is the recolonization with H. pylori from dental plaque. The purpose of this review was to determine whether dental plaque, poor oral hygiene, and periodontal disease were risk factors for H. pylori infection.

  11. Probiotics for the treatment of Helicobacter pylori infection in children

    OpenAIRE

    Pacifico, Lucia; Osborn, John Frederick; Bonci, Enea; Romaggioli, Sara; Baldini, Rossella; Chiesa, Claudio

    2014-01-01

    The combination of a proton pump inhibitor and two antibiotics (clarithromycin plus amoxicillin or metronidazole) has been the recommended first-line therapy since the first guidelines for Helicobacter pylori (H. pylori) infection in children were published. In recent years, the success of eradication therapies has declined, in part due to the development of H. pylori resistant strains. Alternative anti-H. pylori treatments are currently becoming more popular than the traditional eradication ...

  12. Helicobacter pylori infection generates genetic instability in gastric cells

    DEFF Research Database (Denmark)

    Machado, Ana Manuel; Figueiredo, C.; Seruca, R.

    2010-01-01

    The discovery that Helicobacter pylori is associated with gastric cancer has led to numerous studies that investigate the mechanisms by which H. pylori induces carcinogenesis. Gastric cancer shows genetic instability both in nuclear and mitochondrial DNA, besides impairment of important DNA repair...... of the host, such as oxidative damage, methylation, chromosomal instability, microsatellite instability, and mutations. Interestingly, H. pylori infection generates genetic instability in nuclear and mitochondrial DNA. Based on the reviewed literature we conclude that H. pylori infection promotes gastric...

  13. Intratumoral injection of taxol in vivo suppresses A549 tumor showing cytoplasmic vacuolization.

    Science.gov (United States)

    Wang, Chaoyang; Chen, Tongsheng

    2012-04-01

    Based on our recent in vitro studies, this report was designed to explore the mechanism by which high concentration of taxol (70 µM) induced paraptosis-like cell death in human lung carcinoma (A549) cells, and to evaluate the therapeutic efficacy of taxol using A549 tumor-bearing mice in vivo. Exposure of cells to taxol induced time-dependent cytotoxicity and cytoplasmic vacuolization without the involvement of Bax, Bak, Mcl-1, Bcl-XL, and caspase-3. Although taxol treatment induced activating transcription factor 6 (ATF6) cleavage indicative of endoplasmic reticulum (ER) stress, silencing ATF6 by shATF6 did not prevent taxol-induced both cytotoxcity and cytoplasmic vacuolization, suggesting that taxol-induced cytoplasmic vacuolization and cell death were not due to ER stress. Moreover, taxol-treated cells did not show DNA fragmentation and loss of mitochondrial membrane potential, the typical characteristics of apoptosis. In addition, taxol-induced cytoplasmic vacuolization did not show the cellular lysis, the characteristics of oncosis, and positive of β-galactosidase, the characteristic of senescence, indicating that taxol induced paraptosis-like cell death is neither oncosis nor senescence. Moreover, our in vivo data showed that intratumoral injection of taxol (50 mg/kg) in A549 tumor xenograft mice on day 1 and day 19 potently suppressed tumor growth showing significant ER vacuolization without toxicity. In conclusion, high concentration of taxol exhibits a significant anticancer activity by inducing paraptosis-like cell death in vitro and in vivo, without significant toxicity, suggesting a promising therapeutic strategy for apoptosis-resistance cancer by inducing ER vacuolization.

  14. [Protein toxins of Staphylococcus aureus].

    Science.gov (United States)

    Shamsutdinov, A F; Tiurin, Iu A

    2014-01-01

    Main scientific-research studies regarding protein bacterial toxins of the most widespread bacteria that belong to Staphylococcus spp. genus and in particular the most pathogenic species for humans--Staphylococcus aureus, are analyzed. Structural and biological properties of protein toxins that have received the name of staphylococcus pyrogenic toxins (PTSAg) are presented. Data regarding genetic regulation of secretion and synthesis of these toxins and 3 main regulatory genetic systems (agr--accessory gene regulator, xpr--extracellular protein regulator, sar--staphylococcal accessory regulator) that coordinate synthesis of the most important protein toxins and enzymes for virulence of S. aureus, are presented.

  15. Helicobacter pylori VacA, acting through receptor protein tyrosine phosphatase α, is crucial for CagA phosphorylation in human duodenum carcinoma cell line AZ-521

    Science.gov (United States)

    Yahiro, Kinnosuke; Yamasaki, Eiki; Kurazono, Hisao; Akada, Junko; Yamaoka, Yoshio; Niidome, Takuro; Hatakeyama, Masanori; Suzuki, Hidekazu; Yamamoto, Taro; Moss, Joel; Isomoto, Hajime; Hirayama, Toshiya

    2016-01-01

    ABSTRACT Helicobacter pylori, a major cause of gastroduodenal diseases, produces vacuolating cytotoxin (VacA) and cytotoxin-associated gene A (CagA), which seem to be involved in virulence. VacA exhibits pleiotropic actions in gastroduodenal disorders via its specific receptors. Recently, we found that VacA induced the phosphorylation of cellular Src kinase (Src) at Tyr418 in AZ-521 cells. Silencing of receptor protein tyrosine phosphatase (RPTP)α, a VacA receptor, reduced VacA-induced Src phosphorylation. Src is responsible for tyrosine phosphorylation of CagA at its Glu-Pro-Ile-Tyr-Ala (EPIYA) variant C (EPIYA-C) motif in Helicobacter pylori-infected gastric epithelial cells, resulting in binding of CagA to SHP-2 phosphatase. Challenging AZ-521 cells with wild-type H. pylori induced phosphorylation of CagA, but this did not occur when challenged with a vacA gene-disrupted mutant strain. CagA phosphorylation was observed in cells infected with a vacA gene-disrupted mutant strain after addition of purified VacA, suggesting that VacA is required for H. pylori-induced CagA phosphorylation. Following siRNA-mediated RPTPα knockdown in AZ-521 cells, infection with wild-type H. pylori and treatment with VacA did not induce CagA phosphorylation. Taken together, these results support our conclusion that VacA mediates CagA phosphorylation through RPTPα in AZ-521 cells. These data indicate the possibility that Src phosphorylation induced by VacA is mediated through RPTPα, resulting in activation of Src, leading to CagA phosphorylation at Tyr972 in AZ-521 cells. PMID:27935824

  16. Ultrastructural and autoradiographic studies of the role of nucleolar vacuoles in soybean root meristem.

    OpenAIRE

    Dariusz Stepiński

    2004-01-01

    Ultrastructural and autoradiographic studies of nucleoli in soybean root meristematic cells in seedlings: (1) grown for 3 days at 25 degrees C (control), (2) grown for three days at 25 degrees C and for 4 days at 10 degrees C, and (3) grown as in (2) and recovered for 1 day at 25 degrees C were carried out. Control nucleoli had dense structure and a few small nucleolar vacuoles. Chilled plant nucleoli had less dense structure and no vacuoles. Nucleoli of plants recovered at 25 degrees C had b...

  17. Helicobacter Pylori and the Prevention of Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Terrence Sullivan

    2004-01-01

    Full Text Available BACKGROUND: Helicobacter pylori is an important cause of stomach cancer that infects a substantial proportion of the Canadian adult population. H pylori can be detected by noninvasive tests and effectively eradicated by medical treatment. Screening for and treatment of H pylori may represent a significant opportunity for preventive oncology.

  18. Furazolidone therapy for Helicobacter pylori: Is it effective and safe?

    Institute of Scientific and Technical Information of China (English)

    Vincenzo De Francesco; Enzo Ierardi; Cesare Hassan; Angelo Zullo

    2009-01-01

    Some aspects related with the use of furazolidone as a rescue therapy for Helicobacter pylori ( H pylori) infection should be remarked, especially regarding its potential oncologic risk. The inclusion of furazolidone in a treatment regimen for H pylori infection is, at least, controversial, and it does not appear to be safe.

  19. Autoproteolytic Activation of Bacterial Toxins

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    Aimee Shen

    2010-05-01

    Full Text Available Protease domains within toxins typically act as the primary effector domain within target cells. By contrast, the primary function of the cysteine protease domain (CPD in Multifunctional Autoprocessing RTX-like (MARTX and Clostridium sp. glucosylating toxin families is to proteolytically cleave the toxin and release its cognate effector domains. The CPD becomes activated upon binding to the eukaryotic-specific small molecule, inositol hexakisphosphate (InsP6, which is found abundantly in the eukaryotic cytosol. This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing anti-toxin therapeutics. In this review, we summarize recent findings related to defining the regulation of toxin function by the CPD and the development of inhibitors to prevent CPD-mediated activation of bacterial toxins.

  20. Autoproteolytic Activation of Bacterial Toxins

    Science.gov (United States)

    Shen, Aimee

    2010-01-01

    Protease domains within toxins typically act as the primary effector domain within target cells. By contrast, the primary function of the cysteine protease domain (CPD) in Multifunctional Autoprocessing RTX-like (MARTX) and Clostridium sp. glucosylating toxin families is to proteolytically cleave the toxin and release its cognate effector domains. The CPD becomes activated upon binding to the eukaryotic-specific small molecule, inositol hexakisphosphate (InsP6), which is found abundantly in the eukaryotic cytosol. This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing anti-toxin therapeutics. In this review, we summarize recent findings related to defining the regulation of toxin function by the CPD and the development of inhibitors to prevent CPD-mediated activation of bacterial toxins. PMID:22069620

  1. Autoproteolytic activation of bacterial toxins.

    Science.gov (United States)

    Shen, Aimee

    2010-05-01

    Protease domains within toxins typically act as the primary effector domain within target cells. By contrast, the primary function of the cysteine protease domain (CPD) in Multifunctional Autoprocessing RTX-like (MARTX) and Clostridium sp. glucosylating toxin families is to proteolytically cleave the toxin and release its cognate effector domains. The CPD becomes activated upon binding to the eukaryotic-specific small molecule, inositol hexakisphosphate (InsP(6)), which is found abundantly in the eukaryotic cytosol. This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing anti-toxin therapeutics. In this review, we summarize recent findings related to defining the regulation of toxin function by the CPD and the development of inhibitors to prevent CPD-mediated activation of bacterial toxins.

  2. Helicobacter pylori infection in pediatrics

    DEFF Research Database (Denmark)

    Wewer, Anne Vibeke; Kalach, Nicolas

    2003-01-01

    . Also noninvasive tests have been studied in children, including serology, 13C-urea breath test and stool antigen test, showing good results in the different age groups as compared to the gold standard. However, the infection often remains asymptomatic in children and the role of this bacterium......A high prevalence and early colonization of Helicobacter pylori infection in childhood was described again this year in developing countries in contrast to developed ones. Upper gastrointestinal endoscopy including gastric biopsies remains the diagnostic gold standard method for this infection...... place only after susceptibility testing. The association of a proton pump inhibitor and two antibiotics for 1 or 2 weeks gives the best eradication rates. The crucial question to elucidate is whether asymptomatic children should be treated to prevent cancer in the future....

  3. Plasmodium falciparum PfA-M1 aminopeptidase is trafficked via the parasitophorous vacuole and marginally delivered to the food vacuole

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    Nyalwidhe Julius

    2010-06-01

    Full Text Available Abstract Background The Plasmodium falciparum PfA-M1 aminopeptidase, encoded by a single copy gene, displays a neutral optimal activity at pH 7.4. It is thought to be involved in haemoglobin degradation and/or invasion of the host cells. Although a series of inhibitors developed against PfA-M1 suggest that this enzyme is a promising target for therapeutic intervention, the biological function(s of the three different forms of the enzyme (p120, p96 and p68 are not fully understood. Two recent studies using PfA-M1 transfections have also provided conflicting results on PfA-M1 localization within or outside the food vacuole. Alternative destinations, such as the nucleus, have also been proposed. Methods By using a combination of techniques, such as cellular and biochemical fractionations, biochemical analysis, mass-spectrometry, immunofluorescence assays and live imaging of GFP fusions to various PfA-M1 domains, evidence is provided for differential localization and behaviour of the three different forms of PfA-M1 in the infected red blood cell which had not been established before. Results The high molecular weight p120 form of PfA-M1, the only version of the protein with a hydrophobic transmembrane domain, is detected both inside the parasite and in the parasitophorous vacuole while the processed p68 form is strictly soluble and localized within the parasite. The transient intermediate and soluble p96 form is localized at the border of parasitophorous vacuole and within the parasite in a compartment sensitive to high concentrations of saponin. Upon treatment with brefeldin A, the PfA-M1 maturation is blocked and the enzyme remains in a compartment close to the nucleus. Conclusions The PfA-M1 trafficking/maturation scenario that emerges from this data indicates that PfA-M1, synthesized as the precursor p120 form, is targeted to the parasitophorous vacuole via the parasite endoplasmic reticulum/Golgi, where it is converted into the transient p96

  4. Diagnosis of Helicobacter pylori infection and diseases associated with Helicobacter pylori by Helicobacter pylori outer membrane proteins

    Institute of Scientific and Technical Information of China (English)

    Zheng Jiang; Ai-Long Huang; Xiao-Hong Tao; Pi-Long Wang

    2004-01-01

    AIM: To examine the serological response of patients with upper gastrointestinal diseases and Helicobocter pylori(Hpylori)infection to two H pylori outer membrane proteins (OMPs)(Mr18 000 and Mr26 000) acquired by gene recombinanttechnique, and to determine the diagnostic significance of serological tests derived from these OMPs.METHODS: Recombinant vectors encoding the two H pylori OMPs were used to transform and express in BL21 (DE3)E. coli. After purification with Ni2+-NTA agarose resin, colloid gold kits were prepared with purified recombinant proteins to detect H pylori infection and H pylori-associated diseases by the immunity-marker technology. We selected 150 patients with H pyloriinfection and digestive symptoms without previous treatment, induding chronic gastritis (n = 60), duodenal ulcer (n = 30), gastric ulcer (n = 30), and gastric cancer (n = 30).As controls, 33 H pylori-negative healthy volunteers were also recruited. Serum samples were collected from all subjects, and the antibodies to specific proteins of H pylori were tested with the colloid gold test kits. The sensitivity,specificity and accuracy of the colloid gold tests were evaluated, by using the combination of standard diagnostic methods (13C urea breath test and bacteria culture) and classic enzyme-linked immunosorbent assay (ELISA) as reference.RESULTS: After purification with Ni2+-NTA agarose resin,the purity of recombinant fusion proteins was about 95%.The recombinant fusion proteins were recognized by the specific monoclonal antibodies against the two H pylori OMPs,as demonstrated by the ELISA. Of the 150 serum samples from patients infected with H pylori 141 (94.0%) responded positively to the recombinant protein with Mr26 000, while the seropositive rates were 95.0%, 96.7%, 96.7% and 90.0%for patients with H pylori-associated chronic gastritis,duodenal ulcer, gastric ulcer, and gastric cancer respectively.The sensitivity, specificity, and accuracy of the colloid gold kit with Mr26 000

  5. Comparison of IL-6, IL-8 Concentrations in H. pylori- and non-H. pylori-associated Gastritis

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    Gontar Alamsyah Siregar

    2014-12-01

    Full Text Available BACKGROUND: Helicobacter pylori is a non-invasive microorganism causing intense gastric mucosal inflammatory and immune reaction. The gastric mucosal levels of the proinflammatory cytokines Interleukin 6 (IL-6 and IL-8 have been reported to be increased in H. pylori infection, but the serum levels in H. pylori infection is still controversial. The purpose of this study was to investigate the serum levels of IL-6 and IL-8 in H. pylori infection. METHODS: A cross sectional study was done on eighty consecutive gastritis patients admitted to endoscopy units at Adam Malik General Hospital and Permata Bunda Hospital, Medan, Indonesia from May-October 2014. Histopathology was performed for the diagnosis of gastritis. Rapid urease test for diagnosis of H. pylori infection. Serum samples were obtained to determine circulating IL-6 and IL-8. Univariate and bivariate analysis (independent t test were done. RESULTS: There were 41.25% patients infected with H. pylori. Circulatory IL-6 levels were significantly higher in H. pylori-infected patients compared to H. pylori negative, but there were no differences between serum levels of IL-8 in H. pylori positive and negative patients. CONCLUSIONS: The immune response to H. pylori promotes systemic inflammation, which was reflected in an increased level of serum IL-6. Serum levels of IL-8 were not significantly different between H. pylori positive and negative. KEYWORDS: Helicobacter pylori, gastritis, IL-6, IL-8, cytokine.

  6. Anti-Helicobacter pylori therapy significantly reduces Helicobacter pylori-induced gastric mucosal damage in Mongolian gerbils

    Institute of Scientific and Technical Information of China (English)

    Chun-Chao Chang; Sheng-Hsuan Chen; Gi-Shih Lien; Yuarn-Jang Lee; Horng-Yuan Lou; Ching-Ruey Hsieh; Chia-Lang Fang; Shiann Pan

    2005-01-01

    AIM: To investigate the effectiveness of 4 d' anti-Helicobacter pyloritherapy on the H pylori-infected Mongolian gerbils based on physiological and pathological changes.METHODS: We used 6-wk-old male gerbils orally inoculated with H pylori (ATCC43504, 2x108 CFU/mL).Seven weeks after H pylori inoculation, the animals of study group received 4 d' anti-H pylori triple therapy (H pylorieradicated group). Seven days later, all animals of the H pylori-eradicated and control groups (H pylori-infected& H pylori-uninfected groups) were sacrificed. We examined gastric mucosal lesions macroscopically, studied gastritis microscopically and determined the stomach weight ratio, myeloperoxidase (MPO) activity and prostaglandin (PG) E2 level.RESULTS: The results showed that both macroscopic and histological gastric damages were significantly less in H pylori-eradicated group than H pylori-infected group.Stomach weight ratio, MPO activity and PGE2 levels were significantly higher in H pylori-infected group than those in the other two groups.CONCLUSION: Four days' anti-H pylori therapy was effective in the improvement of H pylori-induced gastric lesions in Mongolian gerbils.

  7. Agglutination of Helicobacter pylori coccoids by lectins

    Institute of Scientific and Technical Information of China (English)

    Mar Mar Khin; Jie Song Hua; Hah Cong Ng; Bow Ho; Torkel Wadstrorr

    2000-01-01

    AIM To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms.METHODS Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS Strong agglutination was observed with mannose-specific Concanavalin A (Con A ),fucose-specific Tetragonolobus purpureas ( Lotus A ) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori-lectin agglutination. Interestingly, heating of H.pylori cells at 60℃ for 1 hour was shown to augment the agglutination with all of the lectins tested. CONCLUSION The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during theevents of morphological transformation,resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection.This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease.

  8. Helicobacter Pylori and Gastric Cancer: Clinical Aspects

    Institute of Scientific and Technical Information of China (English)

    Zhi-Qiang Song; Li-Ya Zhou

    2015-01-01

    Objective: Although Helicobacterpylori (H.pylori) is considered as the main etiological factor for gastric cancer, the strategy of screening and treating the oncogenic bacterium is still controversial.The objective was to evaluate the status and progress of the cognition about the relationship between H.pylori infection and gastric cancer from a clinical aspect.Data Sources: The data used in this review were mainly from the PubMed articles published in English from 1984 to 2015.Study Selection: Clinical research articles were selected mainly according to their level of relevance to this topic.Results: Gastric cancer is the fifth most common malignancy and the third leading cause of cancer deaths worldwide.The main etiological factor for gastric cancer is H.pylori infection.About 74.7-89.0% gastric cancer was related to H.pylori infection.Up to date, some regional gastric cancer prevention programs including the detection and treatment of H.pylori infection are under way.Current data obtained from the randomized controlled trials suggest that population-based H.pylori screening and treatment is feasible and cost-effective in preventing gastric cancer;however, a population-based H.pylori eradication campaign would potentially lead to bacterial resistance to the corresponding antibiotics, as well as a negative impact on the normal flora.Conclusions: The important questions of feasibility, program costs, appropriate target groups for intervention, and the potential harm of mass therapy with antibiotics must first be answered before implementing any large-scale program.

  9. Antibiotic susceptibility of Helicobacter pylori in Iceland.

    Science.gov (United States)

    Gunnarsdottir, Anna Ingibjorg; Gudjonsson, Hallgrimur; Hardardottir, Hjordis; Jonsdottir, Karen Drofn; Bjornsson, Einar Stefan

    2017-09-01

    Increasing resistance of Helicobacter pylori (H. pylori) to antibiotics calls for constant re-evaluation of multidrug regimens that have been used to eradicate the infection. The aim of this study was to evaluate the current antibiotic susceptibility of H. pylori in an Icelandic cohort. Patients referred for gastroscopy were recruited prospectively. Those found to have a positive rapid urease test were included in the study. Susceptibility testing was conducted by the Epsilometer test (E-test) method for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline. Results were obtained after three days of incubation in microaerophilic conditions at 37 °C, except for the metronidazole were the first 24 hours were anaerobic. Of the 613 patients who underwent gastroscopy, 138 (23%) had a positive rapid urease test. H. pylori was successfully cultured from 105 (76%) of the urease test positive patients and the isolates were tested for antibiotic susceptibility. Five patients had prior H. pylori eradication. Antibiotic resistance for ampicillin, clarithromycin, levofloxacin, metronidazole and tetracycline was 0%, 9%, 4%, 1% and 0%, respectively. If those who had previously undergone eradication treatment were excluded, the resistance was 0%, 6%, 3%, 1% and 0%, respectively. Clarithromycin resistance was higher amongst women than men, 13% vs. 5%, however, not significantly. Clarithromycin resistance was 60% amongst those who had previously received eradication treatment compared to 6% of those who had not (p pylori isolates can be considered relatively low. Therefore, in the current cohort, standard triple-drug clarithromycin-containing regimen should remain the first-line treatment against H. pylori.

  10. Helicobacter pylori Antibiotic Resistance: Trends Over Time

    Directory of Open Access Journals (Sweden)

    Raymond G Lahaie

    2000-01-01

    Full Text Available Resistance to antibiotics can be a major problem in the treatment of bacterial infections. As the use of antibiotics increases, bacterial resistance to these agents is rising and in many cases is responsible for the failure of treatment regimens. Although the treatment of Helicobacter pylori infection requires the use of more than one antibiotic to obtain adequate eradication rates, the efficacy of the currently used antibiotic combinations has been shown to be decreased by resistance to one of the antibiotics. The use of antibiotics in regimens for the treatment of H pylori is increasing in many countries, including Canada. This increase is both in the use of these antibiotics alone for the treatment of nongastrointestinal infections and in their use in association with proton pump inhibitors for the treatment of H pylori infection. In several European and Asian countries, where resistance to antibiotics is being monitored, it has been demonstrated that H pylori resistance to metronidazole and to clarithromycin increased throughout the 1990s. Thus far, the data available in Canada do not show increased resistance to either of these antibiotics. As for other antibiotics used in the treatment of H pylori infection, such as tetracycline and amoxicillin, the rate of resistance to these agents is still very low and does not constitute a significant problem. Because the efficacy of the regimens used in the treatment of H pylori infection is compromised by resistance to the antibiotics used, it is important that H pylori resistance rates in Canada and throughout the world continue to be monitored. Only with such reliable data can the most optimal regimens be recommended.

  11. Extraction of Staphylococcus aureus toxin from minced meat in Mosul City

    Directory of Open Access Journals (Sweden)

    O. H. Sheet

    2009-01-01

    Full Text Available This study was conducted to isolate and identify of Staph.aureus with its toxin from (41 sample of minced meat from different areas of Mosul city collected between April to July 2007. The positive samples to bacterial isolation reached 14.6%.In order to search the effect of bacterial toxin 0.2 ml and 0.4 ml of the toxins have been give orally and injected interperitonealy , respectively in albino mice. Histopathological changes of this toxin were described, the results showed the presence of vascular degeneration and apoptosis in hepatocyt as well as vascular and fatty degeneration in the tubercular epithelium of kidney. In the brain tissue the lesion was characterize by presence of vacuolation, gliosis and privascular odema, also the results revealed elongation and blunting of villi associated with lymphocytic proliferation in lamina properia of intestine. The histopathological changes were more severe in dose 0.4 ml as compared with 0.2 ml bacterial toxin.

  12. [Peptic Ulcer Disease Associated with Helicobacter pylori Infection].

    Science.gov (United States)

    Yeo, Se-Hwan; Yang, Chang-Hun

    2016-06-25

    Although the global prevalence of peptic ulcer disease (PUD) is decreasing, PUD is still one of the most common upper gastrointestinal diseases in the world due to Helicobacter pylori infection and increased use of non-steroidal anti-inflammatory drugs. In Korea, the prevalence of H. pylori infection is also declining, but it is still the major cause of PUD. The outcomes of H. pylori infection are caused by imbalances between bacterial virulence factors, host factors, and environmental influences. In this review, we describe the prevalence trends of H. pylori infection in Korea, the mechanism of H. pylori infection-related PUD, and treatment strategies.

  13. Innate immune responses to Helicobacter pylori infection: an overview.

    Science.gov (United States)

    Patel, Milan K; Trombly, Melanie I; Kurt-Jones, Evelyn A

    2012-01-01

    Innate immune receptors detect Helicobacter pylori infection and trigger downstream signaling events that result in the production of cytokines and interferon-β. This chapter gives an overview of the receptors and their roles in responding to H. pylori infection and details the downstream signaling events. The tools that have been developed to study the innate immune response to H. pylori are also discussed. Understanding the immune response to H. pylori is critical to develop better treatments for H. pylori-induced disease states including gastric malignancies and cancer.

  14. Helicobacter pylori Infection and atherosclerosis: a systematic review.

    Directory of Open Access Journals (Sweden)

    Reza Karbasi-Afshar

    2015-02-01

    Full Text Available Helicobacter pylori (H. pylori is a spiral-shaped gram negative bacterium that naturally colonizes the human gastric epithelium. In recent years, large evidence has come to the literature strongly proposing causal link between H. pylori and extra gastric disorders. Cardiovascular system is one of the extra gastric organs that can be affected by H. pylori infection. The first evidence suggestive of such an association comes from seroepidemiological evaluations, but histopathological and eradication studies have strongly confirmed existence of a causal association between H. pylori infection and cardiovascular events.

  15. Transcriptional Profiling of Type II Toxin–Antitoxin Genes of Helicobacter pylori under Different Environmental Conditions: Identification of HP0967–HP0968 System

    Science.gov (United States)

    Cárdenas-Mondragón, María G.; Ares, Miguel A.; Panunzi, Leonardo G.; Pacheco, Sabino; Camorlinga-Ponce, Margarita; Girón, Jorge A.; Torres, Javier; De la Cruz, Miguel A.

    2016-01-01

    Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and is responsible for causing peptic ulcers and gastric carcinoma. The expression of virulence factors allows the persistence of H. pylori in the stomach, which results in a chronic, sometimes uncontrolled inflammatory response. Type II toxin–antitoxin (TA) systems have emerged as important virulence factors in many pathogenic bacteria. Three type II TA systems have previously been identified in the genome of H. pylori 26695: HP0315–HP0316, HP0892–HP0893, and HP0894–HP0895. Here we characterized a heretofore undescribed type II TA system in H. pylori, HP0967–HP0968, which is encoded by the bicistronic operon hp0968–hp0967 and belongs to the Vap family. The predicted HP0967 protein is a toxin with ribonuclease activity whereas HP0968 is an antitoxin that binds to its own regulatory region. We found that all type II TA systems were expressed in H. pylori during early stationary growth phase, and differentially expressed in the presence of urea, nickel, and iron, although, the hp0968–hp0967 pair was the most affected under these environmental conditions. Transcription of hp0968–hp0967 was strongly induced in a mature H. pylori biofilm and when the bacteria interacted with AGS epithelial cells. Kanamycin and chloramphenicol considerably boosted transcription levels of all the four type II TA systems. The hp0968–hp0967 TA system was the most frequent among 317 H. pylori strains isolated from all over the world. This study is the first report on the transcription of type II TA genes in H. pylori under different environmental conditions. Our data show that the HP0967 and HP0968 proteins constitute a bona fide type II TA system in H. pylori, whose expression is regulated by environmental cues, which are relevant in the context of infection of the human gastric mucosa. PMID:27920769

  16. Prokaryotic toxin-antitoxin systems: novel regulations of the toxins.

    Science.gov (United States)

    Otsuka, Yuichi

    2016-05-01

    Toxin-antitoxin (TA) systems are widely conserved in prokaryotic plasmids and chromosomes and are linked to many roles in cell physiology, including plasmid maintenance, stress response, persistence and protection from phage infection. A TA system is composed of a stable toxin and a labile antitoxin that inhibits a harmful effect of the cognate toxin. When gene expression from the TA loci is repressed under certain conditions such as nutrient starvation, the toxin is freed from the rapidly degrading antitoxin and obstructs an essential cellular process, such as DNA replication, translation and peptidoglycan synthesis, which subsequently causes growth arrest. TA systems are classified into five types according to the nature and the function of antitoxins, and the activity of toxins is tightly regulated in a variety of ways. This short-review highlights several novel regulatory mechanisms for Escherichia coli toxins that we recently discovered.

  17. Rimmed vacuoles and the added value of SMI-31 staining in diagnosing sporadic inclusion body myositis.

    Science.gov (United States)

    van der Meulen, M F; Hoogendijk, J E; Moons, K G; Veldman, H; Badrising, U A; Wokke, J H

    2001-07-01

    Problems in diagnosing sporadic inclusion body myositis may arise if all clinical features fit a diagnosis of polymyositis, but the muscle biopsy shows some rimmed vacuoles. Recently, immunohistochemistry with an antibody directed against phosphorylated neurofilament (SMI-31) has been advocated as a diagnostic test for sporadic inclusion body myositis. The aims of the present study were to define a quantitative criterion to differentiate sporadic inclusion body myositis from polymyositis based on the detection of rimmed vacuoles in the haematoxylin-eosin staining and to evaluate the additional diagnostic value of the SMI-31 staining. Based on clinical criteria and creatine kinase levels in patients with endomysial infiltrates, 18 patients complied with the diagnosis of sporadic inclusion body myositis, and 17 with the diagnosis of polymyositis. A blinded observer counted the abnormal fibres in haematoxylin-eosin-stained sections and in SMI-31-stained sections. The optimal cut-off in the haematoxylin-eosin test was 0.3% vacuolated fibres. Adding the SMI-31 staining significantly increased the positive predictive value from 87 to 100%, but increased the negative predictive value only to small extent. We conclude that (1) patients with clinical and laboratory features of polymyositis, including response to treatment, may show rimmed vacuoles in their muscle biopsy and that (2) adding the SMI-31 stain can be helpful in differentiating patients who respond to treatment from patients who do not.

  18. An NPF transporter exports a central monoterpene indole alkaloid intermediate from the vacuole

    DEFF Research Database (Denmark)

    Payne, Richard; Xu, Deyang; Foureau, Emilien

    2017-01-01

    /peptide family (NPF) transporter from Catharanthus roseus, CrNPF2.9, that exports strictosidine, the central intermediate of this pathway, into the cytosol from the vacuole. This discovery highlights the role that intracellular localization plays in specialized metabolism, and sets the stage for understanding...

  19. PAS-positive lymphocyte vacuoles can be used as diagnostic screening test for Pompe disease.

    Science.gov (United States)

    Hagemans, Marloes L C; Stigter, Rolinda L; van Capelle, Carine I; van der Beek, Nadine A M E; Winkel, Leon P F; van Vliet, Laura; Hop, Wim C J; Reuser, Arnold J J; Beishuizen, Auke; van der Ploeg, Ans T

    2010-04-01

    Screening of blood films for the presence of periodic acid-Schiff (PAS)-positive lymphocyte vacuoles is sometimes used to support the diagnosis of Pompe disease, but the actual diagnostic value is still unknown. We collected peripheral blood films from 65 untreated Pompe patients and 51 controls. Lymphocyte vacuolization was quantified using three methods: percentage vacuolated lymphocytes, percentage PAS-positive lymphocytes, and a PAS score depending on staining intensity. Diagnostic accuracy of the tests was assessed using receiver operating characteristic (ROC) curves. All three methods fully discerned classic infantile patients from controls. The mean values of patients with milder forms of Pompe disease were significantly higher than those of controls, but full separation was not obtained. The area under the ROC curve was 0.98 for the percentage vacuolated lymphocytes (optimal cutoff value 3; sensitivity 91%, specificity 96%) and 0.99 for the percentage PAS-positive lymphocytes and PAS score (optimal cutoff value 9; sensitivity 100%, specificity 98%). Our data indicate that PAS-stained blood films can be used as a reliable screening tool to support a diagnosis of Pompe disease. The percentage of PAS-positive lymphocytes is convenient for use in clinical practice but should always be interpreted in combination with other clinical and laboratory parameters.

  20. Retromer and the dynamin Vps1 cooperate in the retrieval of transmembrane proteins from vacuoles

    NARCIS (Netherlands)

    Arlt, Henning; Reggiori, Fulvio; Ungermann, Christian

    2015-01-01

    Endosomes are dynamic organelles that need to combine the ability to successfully deliver proteins and lipids to the lysosome-like vacuole, and recycle others to the Golgi or the plasma membrane. We now show that retromer, which is implicated in retrieval of proteins from endosomes to the Golgi or t

  1. Effects of lysosomal membrane protein depletion on the Salmonella-containing vacuole.

    Directory of Open Access Journals (Sweden)

    Everett A Roark

    Full Text Available Salmonella is an intracellular bacterial pathogen that replicates within a membrane-bound vacuole in host cells. The major lysosomal membrane proteins 1 and 2 (LAMP-1 and LAMP-2 are recruited to the Salmonella-containing vacuole as well as Salmonella- associated filaments (Sifs that emerge from the vacuole. LAMP-1 is a dominant membrane marker for the vacuole and Sifs. Its colocalization with both is dependent on a major secreted bacterial virulence protein, SifA. Here, we show that SifA is required for the recruitment of LAMP-2 and can be used as a second independent marker for both the bacterial vacuolar membrane and Sifs. Further, RNAi studies revealed that in LAMP-1 depleted cells, the bacteria remain membrane bound as measured by their association with LAMP-2 protein. In contrast, LAMP-2 depletion increased the amount of LAMP-1 free bacteria. Together, the data suggests that despite its abundance, LAMP-1 is not essential, but LAMP-2 may be partially important for the Salmonella-containing vacuolar membrane.

  2. Caspase-11 activation requires lysis of pathogen-containing vacuoles by IFN-induced GTPases.

    Science.gov (United States)

    Meunier, Etienne; Dick, Mathias S; Dreier, Roland F; Schürmann, Nura; Kenzelmann Broz, Daniela; Warming, Søren; Roose-Girma, Merone; Bumann, Dirk; Kayagaki, Nobuhiko; Takeda, Kiyoshi; Yamamoto, Masahiro; Broz, Petr

    2014-05-15

    Lipopolysaccharide from Gram-negative bacteria is sensed in the host cell cytoplasm by a non-canonical inflammasome pathway that ultimately results in caspase-11 activation and cell death. In mouse macrophages, activation of this pathway requires the production of type-I interferons, indicating that interferon-induced genes have a critical role in initiating this pathway. Here we report that a cluster of small interferon-inducible GTPases, the so-called guanylate-binding proteins, is required for the full activity of the non-canonical caspase-11 inflammasome during infections with vacuolar Gram-negative bacteria. We show that guanylate-binding proteins are recruited to intracellular bacterial pathogens and are necessary to induce the lysis of the pathogen-containing vacuole. Lysis of the vacuole releases bacteria into the cytosol, thus allowing the detection of their lipopolysaccharide by a yet unknown lipopolysaccharide sensor. Moreover, recognition of the lysed vacuole by the danger sensor galectin-8 initiates the uptake of bacteria into autophagosomes, which results in a reduction of caspase-11 activation. These results indicate that host-mediated lysis of pathogen-containing vacuoles is an essential immune function and is necessary for efficient recognition of pathogens by inflammasome complexes in the cytosol.

  3. Retromer and the dynamin Vps1 cooperate in the retrieval of transmembrane proteins from vacuoles

    NARCIS (Netherlands)

    Arlt, Henning; Reggiori, Fulvio; Ungermann, Christian

    2015-01-01

    Endosomes are dynamic organelles that need to combine the ability to successfully deliver proteins and lipids to the lysosome-like vacuole, and recycle others to the Golgi or the plasma membrane. We now show that retromer, which is implicated in retrieval of proteins from endosomes to the Golgi or t

  4. Vacuoles in sperm head are not associated with head morphology, DNA damage and reproductive success.

    Science.gov (United States)

    Fortunato, Adriana; Boni, Raffaele; Leo, Rita; Nacchia, Giuseppina; Liguori, Francesca; Casale, Sofia; Bonassisa, Paolo; Tosti, Elisabetta

    2016-02-01

    In this retrospective study of 873 men enrolled for assisted reproduction techniques, relationships between sperm quality parameters, motile sperm organelle morphology examination (MSOME), DNA damage and live birth rate were evaluated. The presence of vacuoles in the sperm heads was detected by MSOME. Either chromatin decondensation or DNA fragmentation was used to study DNA damage. Results show that age significantly affected some of the examined parameters. In particular, sperm concentration was positively correlated (R = 0.088; P = 0.01) and chromatin decondensation was negatively correlated (R = -0.102; P = 0.003) with age. Furthermore, live birth rate was significantly lower in men aged 40 years or older (P fragmentation and live birth rate. Considering sperm heads in relation to the shape (normal/abnormal) and vacuoles (presence/absence), no significant variations in the occurrence of vacuoles in either normal or abnormal heads were found. These data suggest that vacuoles are physiological features that do not alter sperm functionality, and it seems that MSOME is not necessary for increasing the success of assisted reproduction techniques.

  5. PAS-positive lymphocyte vacuoles can be used as diagnostic screening test for Pompe disease

    NARCIS (Netherlands)

    M.L.C. Hagemans (Marloes); R.L. Stigter; C.I. van Capelle (Carine); N.A.M.E. van der Beek (Nadine); L.P.F. Winkel (Léon); L. van Vliet (Laura); W.C.J. Hop (Wim); A.J.J. Reuser (Arnold); A. Beishuizen (Auke); A.T. van der Ploeg (Ans)

    2010-01-01

    textabstractScreening of blood films for the presence of periodic acid-Schiff (PAS)-positive lymphocyte vacuoles is sometimes used to support the diagnosis of Pompe disease, but the actual diagnostic value is still unknown. We collected peripheral blood films from 65 untreated Pompe patients and 51

  6. The internalization of Helicobacter pylori plays a role in the failure of H. pylori eradication.

    Science.gov (United States)

    Wang, You-Hua; Lv, Zhi-Fa; Zhong, Yao; Liu, Dong-Sheng; Chen, Shu-Ping; Xie, Yong

    2017-02-01

    Helicobacter pylori (H. pylori) internalization involves invasion of cells by the bacterium. Several studies have shown that H. pylori can invade human gastric epithelial cells, immune cells, and Candida yeast in vivo and in vitro. Whether bacterial invasion plays a role in eradication failure is unclear. To investigate the relationship between H. pylori invasion of GES-1 cells and H. pylori eradication failure. Forty-two clinical strains isolated from H. pylori-positive patients with different outcomes after treatment with furazolidone-based therapy were examined (17 failures and 25 successes). The H. pylori strains were shown to be susceptible to amoxicillin and furazolidone, and the patients also exhibited good compliance. Genotyping was performed for cagA and vacA (s and m). The antibiotic susceptibility of the strains to amoxicillin, furazolidone, clarithromycin, metronidazole, and levofloxacin was determined by E-tests. The levels of H. pylori invasion of GES-1 cells were detected by gentamicin colony-forming unit assays. The internalization level in the eradication success group was 5.40±5.78 × 10(-3)  cfu/cell, and the median was 6.194 × 10(-3)  cfu/cell; the internalization level in the eradication failure group was 8.98±5.40 × 10(-3)  cfu/cell, and the median was 10.28 × 10(-3)  cfu/cell. The eradication failure group showed a greater invasion level than the eradication success group (P.05). The results showed that H. pylori invasion of the gastric epithelia might play a role in eradication failure. © 2016 John Wiley & Sons Ltd.

  7. Horizontal versus familial transmission of Helicobacter pylori.

    Directory of Open Access Journals (Sweden)

    Sandra Schwarz

    2008-10-01

    Full Text Available Transmission of Helicobacter pylori is thought to occur mainly during childhood, and predominantly within families. However, due to the difficulty of obtaining H. pylori isolates from large population samples and to the extensive genetic diversity between isolates, the transmission and spread of H. pylori remain poorly understood. We studied the genetic relationships of H. pylori isolated from 52 individuals of two large families living in a rural community in South Africa and from 43 individuals of 11 families living in urban settings in the United Kingdom, the United States, Korea, and Colombia. A 3,406 bp multilocus sequence haplotype was determined for a total of 142 H. pylori isolates. Isolates were assigned to biogeographic populations, and recent transmission was measured as the occurrence of non-unique isolates, i.e., isolates whose sequences were identical to those of other isolates. Members of urban families were almost always infected with isolates from the biogeographic population that is common in their location. Non-unique isolates were frequent in urban families, consistent with familial transmission between parents and children or between siblings. In contrast, the diversity of H. pylori in the South African families was much more extensive, and four distinct biogeographic populations circulated in this area. Non-unique isolates were less frequent in South African families, and there was no significant correlation between kinship and similarity of H. pylori sequences. However, individuals who lived in the same household did have an increased probability of carrying the same non-unique isolates of H. pylori, independent of kinship. We conclude that patterns of spread of H. pylori under conditions of high prevalence, such as the rural South African families, differ from those in developed countries. Horizontal transmission occurs frequently between persons who do not belong to a core family, blurring the pattern of familial

  8. Lipopolysaccharide Structure and Biosynthesis in Helicobacter pylori.

    Science.gov (United States)

    Li, Hong; Liao, Tingting; Debowski, Aleksandra W; Tang, Hong; Nilsson, Hans-Olof; Stubbs, Keith A; Marshall, Barry J; Benghezal, Mohammed

    2016-12-01

    This review covers the current knowledge and gaps in Helicobacter pylori lipopolysaccharide (LPS) structure and biosynthesis. H. pylori is a Gram-negative bacterium which colonizes the luminal surface of the human gastric epithelium. Both a constitutive alteration of the lipid A preventing TLR4 elicitation and host mimicry of the Lewis antigen decorated O-antigen of H. pylori LPS promote immune escape and chronic infection. To date, the complete structure of H. pylori LPS is not available, and the proposed model is a linear arrangement composed of the inner core defined as the hexa-saccharide (Kdo-LD-Hep-LD-Hep-DD-Hep-Gal-Glc), the outer core composed of a conserved trisaccharide (-GlcNAc-Fuc-DD-Hep-) linked to the third heptose of the inner core, the glucan, the heptan and a variable O-antigen, generally consisting of a poly-LacNAc decorated with Lewis antigens. Although the glycosyltransferases (GTs) responsible for the biosynthesis of the H. pylori O-antigen chains have been identified and characterized, there are many gaps in regard to the biosynthesis of the core LPS. These limitations warrant additional mutagenesis and structural studies to obtain the complete LPS structure and corresponding biosynthetic pathway of this important gastric bacterium.

  9. Treatment of Helicobacter Pylori in Children

    Directory of Open Access Journals (Sweden)

    F Famouri

    2014-04-01

    Full Text Available Childrenwith Helicobacter infection need treatment. The aim of treatment is elimination of H.Pylori. Most patients with this infection are asymptomatic and without peptic disease. Treatment and management of these patients are controversy. Conventional Treatment: The best treatment for H. pylori eradication regimens should have cure rates of at least 80%, be without major side effects, and induce minimal bacterial resistance. Antibiotics alone have not achieved this. Luminal acidity influences both the effectiveness of some antimicrobial agents and the survival of the bacteri; thus antibiotics have been combined with acid suppression such as proton pump inhibitors (PPIs, bismuth, or H2 antagonists. The “classic” regimen is treatment twice daily for 7 days with a PPI and clarithromycin plus either amoxicillin or metronidazole Bismuth has been used in the treatment of peptic ulcer disease and 1 part o quadruple therapy for H.Pylori but compliance of children for it is low.   Sequential Therapy  Sequential therapyinvolves dual therapy with a PPI and amoxicillin for 5 days followed sequentially by clarithromycin, Tinidazole and omeperazole for 5 days or other triple therapy for 7 days. This treatment has had 97% efficacy.   Adjunctive Therapies A number of studies have showed the potential benefits of probiotic therapy in H. pylori treatment regimens.Consumption of these drugs accompanied with other medications increase H.Pylori eradication.    

  10. Can Helicobacter pylori infection influence human reproduction?

    Science.gov (United States)

    Moretti, Elena; Figura, Natale; Collodel, Giulia; Ponzetto, Antonio

    2014-05-21

    Helicobacter pylori (H. pylori) infection could be associated with extra-digestive diseases. Here, we report the evidences concerning the decrease in reproductive potential occurring in individuals infected by H. pylori, especially by strains expressing CagA. This infection is more prevalent in individuals with fertility disorders. Infected women have anti-H. pylori antibodies in cervical mucus and follicular fluid that may decrease sperm motility and cross react immunologically with spermatozoa, conceivably hampering the oocyte/sperm fusion. Infection by CagA positive organisms enhances the risk of preeclampsia, which is a main cause of foetus death. These findings are supported by the results of experimental infections of pregnant mice, which may cause reabsorption of a high number of foetuses and alter the balance between Th1 and Th2 cell response. Infected men have decreased sperm motility, viability and numbers of normally shaped sperm and augmented systemic levels of inflammatory cytokines, such as tumor necrosis factor-α, which may damage spermatozoa. In countries where parasitic infestation is endemic, detrimental effects of infection upon spermatozoa may not occur, because the immune response to parasites could determine a switch from a predominant Th1 type to Th2 type lymphocytes, with production of anti-inflammatory cytokines. In conclusion, the evidences gathered until now should be taken into consideration for future studies aiming to explore the possible role of H. pylori infection on human reproduction.

  11. Helicobacter pylori: prospettive per un vaccino

    Directory of Open Access Journals (Sweden)

    Giuseppe Del Giudice

    2003-09-01

    Full Text Available Helicobacter pylori causes one of the most widespread infections worldwide: it affects more than 50% of the human population, and is responsible for serious gastric pathologies such as chronic gastritis, peptic ulcer, atrophic gastritis and, in some individuals, gastric cancer. Current treatments with antibiotics are efficacious, but encounters several drawbacks at the level of compliance, side effects, antibiotic resistance, etc.The availability of vaccines could contribute in reducing the burden of H. pylori associated diseases. Several bacterial antigens have been identified as virulence factors and proposed as potential vaccine candidates. Some of these antigens have been tested in experimental animal models of challenge with H. pylori. The experiments in animals have shown that prophylactic and therapeutic vaccination against H. pylori is indeed feasible. Several open questions still remain concerning the understanding of the host-microbe relationship and the quality of the immune response which should be induced in order to confer protective immunity in man.The answers to these questions will be crucial in helping the preparation of appropriate vaccine formulations able to efficaciously protect humans both prophylactically and therapeutically. A few clinical trials have been carried out so far with still limited results. Other trials in humans are in progress and are planned for the next few years.The final hope is that these new vaccines will show the expected efficacy against H. pylori and will permit the elimination of this pathogen which has cohabited with humans for more than 100,000 years.

  12. Helicobacter Pylori Infection in the Elderly

    Directory of Open Access Journals (Sweden)

    Jyh-Ming Liou

    2008-12-01

    Full Text Available The elderly often seek medical attention because of gastroduodenal diseases. Helicobacter pylori (H. pylori infection is associated with several gastroduodenal diseases and its prevalence increases with age worldwide. It is estimated that 10–15% of infected patients will have peptic ulcer disease and 1% of patients will have gastric cancer or mucosa-associated lymphoid tissue lymphoma. Notably, the most severe clinical outcomes, i.e., gastric cancer and complicated peptic ulcer diseases, usually occur in elderly patients. Thus the test-and-treatment strategy is not recommended for elderly patients with uninvestigated dyspepsia. However, biopsy specimens for the rapid urease test and histology should be taken from both the antrum and corpus to increase the detection rate in elderly patients, especially in those with atrophic gastritis. The urea breath test may increase the detection rate if the rapid urease test or histology are negative in elderly patients with atrophic gastritis. Standard triple therapy and sequential therapy can achieve satisfactory eradication rates for H. pylori in elderly patients. Elderly patients with peptic ulcers may have a similar benefit from treatment of H. pylori infection as non-elderly patients. Eradication of H. pylori infection may also lead to improvement in histologic grading of gastritis, but the risk of gastric cancer cannot be completely reduced, especially in patients with existing premalignant lesions.

  13. Lektine, Toxine und Immunotoxine

    Science.gov (United States)

    Uhlenbruck, Gerhard

    1981-12-01

    A definition and classification of lectins (carbohydrate-binding (glyco)proteins) is given on the basis of new data and experimental results. Especially the biological role of bacterial, vertebrate and sponge lectins is discussed. The lectin-toxin combination offers an excellent model not only for studying adhesion to and penetration through the cell membrane, but also for hybridization with antibody fragments showing anti-tumor specificity.

  14. Adjustment of host cells for accommodation of symbiotic bacteria: vacuole defunctionalization, HOPS suppression, and TIP1g retargeting in Medicago

    NARCIS (Netherlands)

    Gavrin, A.Y.; Kaiser, B.N.; Geiger, D.; Tyerman, S.D.; Wen, Z.; Bisseling, T.; Fedorova, E.E.

    2014-01-01

    In legume–rhizobia symbioses, the bacteria in infected cells are enclosed in a plant membrane, forming organelle-like compartments called symbiosomes. Symbiosomes remain as individual units and avoid fusion with lytic vacuoles of host cells. We observed changes in the vacuole volume of infected

  15. Adjustment of host cells for accommodation of symbiotic bacteria: vacuole defunctionalization, HOPS suppression, and TIP1g retargeting in Medicago.

    Science.gov (United States)

    Gavrin, Aleksandr; Kaiser, Brent N; Geiger, Dietmar; Tyerman, Stephen D; Wen, Zhengyu; Bisseling, Ton; Fedorova, Elena E

    2014-09-01

    In legume-rhizobia symbioses, the bacteria in infected cells are enclosed in a plant membrane, forming organelle-like compartments called symbiosomes. Symbiosomes remain as individual units and avoid fusion with lytic vacuoles of host cells. We observed changes in the vacuole volume of infected cells and thus hypothesized that microsymbionts may cause modifications in vacuole formation or function. To examine this, we quantified the volumes and surface areas of plant cells, vacuoles, and symbiosomes in root nodules of Medicago truncatula and analyzed the expression and localization of VPS11 and VPS39, members of the HOPS vacuole-tethering complex. During the maturation of symbiosomes to become N2-fixing organelles, a developmental switch occurs and changes in vacuole features are induced. For example, we found that expression of VPS11 and VPS39 in infected cells is suppressed and host cell vacuoles contract, permitting the expansion of symbiosomes. Trafficking of tonoplast-targeted proteins in infected symbiotic cells is also altered, as shown by retargeting of the aquaporin TIP1g from the tonoplast membrane to the symbiosome membrane. This retargeting appears to be essential for the maturation of symbiosomes. We propose that these alterations in the function of the vacuole are key events in the adaptation of the plant cell to host intracellular symbiotic bacteria. © 2014 American Society of Plant Biologists. All rights reserved.

  16. Saccharomyces cerevisiae depend on vesicular traffic between Golgi and vacuole when Inositolphosphorylceramide synthase Aur1 is inactivated

    DEFF Research Database (Denmark)

    Voynova, Natalia S; Roubaty, Carole; Vazquez, Hector M

    2015-01-01

    that vesicle mediated transport between Golgi, endosomes and vacuole becomes crucial for survival when Aur1 is repressed, irrespective of the mode of repression. In addition, vacuolar acidification becomes essential when cells are acutely stressed by AbA, and Quinacrine uptake into vacuoles shows that Ab...

  17. Adjustment of host cells for accommodation of symbiotic bacteria: vacuole defunctionalization, HOPS suppression, and TIP1g retargeting in Medicago

    NARCIS (Netherlands)

    Gavrin, A.Y.; Kaiser, B.N.; Geiger, D.; Tyerman, S.D.; Wen, Z.; Bisseling, T.; Fedorova, E.E.

    2014-01-01

    In legume–rhizobia symbioses, the bacteria in infected cells are enclosed in a plant membrane, forming organelle-like compartments called symbiosomes. Symbiosomes remain as individual units and avoid fusion with lytic vacuoles of host cells. We observed changes in the vacuole volume of infected cell

  18. Regulation of RKIP function by Helicobacter pylori in gastric cancer.

    Directory of Open Access Journals (Sweden)

    Erika L Moen

    Full Text Available Helicobacter pylori (H. pylori is a gram-negative, spiral-shaped bacterium that infects more than half of the world's population and is a major cause of gastric adenocarcinoma. The mechanisms that link H. pylori infection to gastric carcinogenesis are not well understood. In the present study, we report that the Raf-kinase inhibitor protein (RKIP has a role in the induction of apoptosis by H. pylori in gastric epithelial cells. Western blot and luciferase transcription reporter assays demonstrate that the pathogenicity island of H. pylori rapidly phosphorylates RKIP, which then localizes to the nucleus where it activates its own transcription and induces apoptosis. Forced overexpression of RKIP enhances apoptosis in H. pylori-infected cells, whereas RKIP RNA inhibition suppresses the induction of apoptosis by H. pylori infection. While inducing the phosphorylation of RKIP, H. pylori simultaneously targets non-phosphorylated RKIP for proteasome-mediated degradation. The increase in RKIP transcription and phosphorylation is abrogated by mutating RKIP serine 153 to valine, demonstrating that regulation of RKIP activity by H. pylori is dependent upon RKIP's S153 residue. In addition, H. pylori infection increases the expression of Snail, a transcriptional repressor of RKIP. Our results suggest that H. pylori utilizes a tumor suppressor protein, RKIP, to promote apoptosis in gastric cancer cells.

  19. Significance of dormant forms of Helicobacter pylori in ulcerogenesis

    Science.gov (United States)

    Reshetnyak, Vasiliy Ivanovich; Reshetnyak, Tatiana Magomedalievna

    2017-01-01

    Nearly half of the global population are carriers of Helicobacter pylori (H. pylori), a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease (PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However, the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms, but also contribute to the conversion of H. pylori into the resting (dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms, such as S-shaped, C-shaped, U-shaped, and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability. PMID:28785141

  20. N-acetylcysteine, a novel treatment for Helicobacter pylori infection.

    Science.gov (United States)

    Huynh, Hien Quoc; Couper, Richard T L; Tran, Cuong D; Moore, Lynette; Kelso, Richard; Butler, Ross N

    2004-01-01

    N-Acetylcysteine (NAC), being both a mucolytic agent and a thiol-containing antioxidant, may affect the establishment and maintenance of H. pylori infection within the gastric mucus layer and mucosa. Agar and broth dilution susceptibility tests determined the MIC of H. pylori strain SSI to NAC. H. pylori load in SSI strain-infected C57BL mice was determined as colony forming units per gram of gastric tissue. Gastritis assessment was scored and gastric surface hydrophobicity was determined by contact angle measurement. MICs of NAC were 5 to 10 and 10 to 15 mg/ml using the agar dilution and broth dilution methods, respectively. NAC (120 mg per day for 14 days) reduced the H. pylori load in mice by almost 1 log compared with sham treatment. Pretreatment with NAC (40 mg/day) also significantly reduced the H. pylori load but did not prevent H. pylori colonization. Both H. pylori infection and NAC reduced the surface hydrophobicity of murine gastric mucosa. No significant differences were observed in the gastritis scores of H. felis- or H. pylori-infected mice receiving either NAC or sham treatments. This study demonstrates that NAC inhibits the growth of H. pylori in both agar and broth susceptibility tests and in H. pylori-infected mice. NAC did not alter the severity of H. pylori- or H. felis-induced gastritis.

  1. Significance of dormant forms of Helicobacter pylori in ulcerogenesis.

    Science.gov (United States)

    Reshetnyak, Vasiliy Ivanovich; Reshetnyak, Tatiana Magomedalievna

    2017-07-21

    Nearly half of the global population are carriers of Helicobacter pylori (H. pylori), a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease (PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However, the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms, but also contribute to the conversion of H. pylori into the resting (dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms, such as S-shaped, C-shaped, U-shaped, and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability.

  2. Lymphoid follicles in children with Helicobacter pylori-negative gastritis.

    Science.gov (United States)

    Broide, Efrat; Richter, Vered; Mendlovic, Sonia; Shalem, Tzippora; Eindor-Abarbanel, Adi; Moss, Steven F; Shirin, Haim

    2017-01-01

    The prevalence of Helicobacter pylori gastritis has been declining, whereas H. pylori-negative gastritis has become more common. We evaluated chronic gastritis in children with regard to H. pylori status and celiac disease (CD). Demographic, clinical, endoscopic, and histologic features of children who underwent elective esophagogastroduodenoscopy were reviewed retrospectively. Gastric biopsies from the antrum and corpus of the stomach were graded using the Updated Sydney System. H. pylori presence was defined by hematoxylin and eosin, Giemsa, or immunohistochemical staining and urease testing. A total of 184 children (61.9% female) met the study criteria with a mean age of 10 years. A total of 122 (66.3%) patients had chronic gastritis; 74 (60.7%) were H. pylori-negative. Children with H. pylori-negative gastritis were younger (p=0.003), were less likely to present with abdominal pain (p=0.02), and were mostly of non-Arabic origin (p=0.011). Nodular gastritis was found to be less prevalent in H. pylori-negative gastritis (6.8%) compared with H. pylori-positive gastritis (35.4%, ppylori-positive group (ppylori. Although less typical, lymphoid follicles were demonstrated in 51.3% of H. pylori-negative patients. The presence or absence of CD was not associated with histologic findings in H. pylori-negative gastritis. Our findings suggest that lymphoid follicles are a feature of H. pylori-negative gastritis in children independent of their CD status.

  3. [Cytolethal distending toxins].

    Science.gov (United States)

    Curová, K; Kmeťová, M; Siegfried, L

    2014-06-01

    Cytolethal distending toxins (CDT) are intracellularly acting proteins which interfere with the eukaryotic cell cycle. They are produced by Gram-negative bacteria with affinity to mucocutaneous surfaces and could play a role in the pathogenesis of various mammalian diseases. The functional toxin is composed of three proteins: CdtB entering the nucleus and by its nuclease activity inducing nuclear fragmentation and chromatin disintegration, CdtA, and CdtC, the two latter being responsible for toxin attachment to the surface of the target cell. Cytotoxic effect of CDT leads to the cell cycle arrest before the cell enters mitosis and to further changes (cell distension and death, apoptosis) depending on the cell type. Thus, CDT may function as a virulence factor in pathogenic bacteria that produce it and thus may contribute to the initiation of certain diseases. Most important are inflammatory bowel diseases caused by intestinal bacteria, periodontitis with Aggregatibacter actinomycetemcomitans as the aetiologic agent and ulcus molle where Haemophilus ducreyi is the causative agent.

  4. Current Therapy for Helicobacter pylori Infection in Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Benjamin D Gold

    1999-01-01

    Full Text Available Helicobacter pylori infects approximately 50% of the world’s population and is a definitive cause of gastroduodenal disease (ie, gastritis, duodenal and gastric ulcers in children and adults. Four consensus conferences held around the globe have brought together clinicians, scientists, epidemiologists and health care economists to discuss the role of the gastric pathogen H pylori in human gastroduodenal disease. At each of these conferences, the overriding objective was to reach a consensus on the development of practical guidelines for the diagnosis and treatment of H pylori-infected individuals. However, it was not until the Canadian H pylori Consensus Conference, held in November 1997, that the issues of H pylori infection in children were addressed. Therapies for H pylori infection in children, presented in part at the First Canadian Paediatric H pylori Consensus Conference, held in Victoria, British Columbia, November 1998, are reviewed in this paper.

  5. Helicobacter pylori infection generates genetic instability in gastric cells

    DEFF Research Database (Denmark)

    Machado, Ana Manuel; Figueiredo, C.; Seruca, R.

    2010-01-01

    The discovery that Helicobacter pylori is associated with gastric cancer has led to numerous studies that investigate the mechanisms by which H. pylori induces carcinogenesis. Gastric cancer shows genetic instability both in nuclear and mitochondrial DNA, besides impairment of important DNA repair...... pathways. As such, this review highlights the consequences of H. pylori infection on the integrity of DNA in the host cells. By down-regulating major DNA repair pathways, H. pylori infection has the potential to generate mutations. In addition, H. pylori infection can induce direct changes on the DNA...... of the host, such as oxidative damage, methylation, chromosomal instability, microsatellite instability, and mutations. Interestingly, H. pylori infection generates genetic instability in nuclear and mitochondrial DNA. Based on the reviewed literature we conclude that H. pylori infection promotes gastric...

  6. Method for detecting biological toxins

    Energy Technology Data Exchange (ETDEWEB)

    Ligler, F.S.; Campbell, J.R.

    1992-01-01

    Biological toxins are indirectly detected by using polymerase chain reaction to amplify unique nucleic acid sequences coding for the toxins or enzymes unique to toxin synthesis. Buffer, primers coding for the unique nucleic acid sequences and an amplifying enzyme are added to a sample suspected of containing the toxin. The mixture is then cycled thermally to exponentially amplify any of these unique nucleic acid sequences present in the sample. The amplified sequences can be detected by various means, including fluorescence. Detection of the amplified sequences is indicative of the presence of toxin in the original sample. By using more than one set of labeled primers, the method can be used to simultaneously detect several toxins in a sample.

  7. Intracellular trafficking of bacterial toxins.

    Science.gov (United States)

    Williams, Jeffrey M; Tsai, Billy

    2016-08-01

    Bacterial toxins often translocate across a cellular membrane to gain access into the host cytosol, modifying cellular components in order to exert their toxic effects. To accomplish this feat, these toxins traffic to a membrane penetration site where they undergo conformational changes essential to eject the toxin's catalytic subunit into the cytosol. In this brief review, we highlight recent findings that elucidate both the trafficking pathways and membrane translocation mechanisms of toxins that cross the plasma, endosomal, or endoplasmic reticulum (ER) membrane. These findings not only illuminate the specific nature of the host-toxin interactions during entry, but should also provide additional therapeutic strategies to prevent or alleviate the bacterial toxin-induced diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Helicobacter pylori's cholesterol uptake impacts resistance to docosahexaenoic acid.

    Science.gov (United States)

    Correia, Marta; Casal, Susana; Vinagre, João; Seruca, Raquel; Figueiredo, Ceu; Touati, Eliette; Machado, José C

    2014-05-01

    Helicobacter pylori colonizes half of the world population and is associated with gastric cancer. We have previously demonstrated that docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid known for its anti-inflammatory and antitumor effects, directly inhibits H. pylori growth in vitro and in mice. Nevertheless, the concentration of DHA shown to reduce H. pylori mice gastric colonization was ineffective in vitro. Related to the auxotrophy of H. pylori for cholesterol, we hypothesize that other mechanisms, in addition to DHA direct antibacterial effect, must be responsible for the reduction of the infection burden. In the present study we investigated if DHA affects also H. pylori growth, by reducing the availability of membrane cholesterol in the epithelial cell for H. pylori uptake. Levels of cholesterol in gastric epithelial cells and of cholesteryl glucosides in H. pylori were determined by thin layer chromatography and gas chromatography. The consequences of epithelial cells' cholesterol depletion on H. pylori growth were assessed in liquid cultures. We show that H. pylori uptakes cholesterol from epithelial cells. In addition, DHA lowers cholesterol levels in epithelial cells, decreases its de novo synthesis, leading to a lower synthesis of cholesteryl glucosides by H. pylori. A previous exposition of H. pylori to cholesterol influences the bacterium response to the direct inhibitory effect of DHA. Overall, our results suggest that a direct effect of DHA on H. pylori survival is modulated by its access to epithelial cell cholesterol, supporting the notion that cholesterol enhances the resistance of H. pylori. The cholesterol-dependent resistance of H. pylori to antimicrobial compounds raises new important aspects for the development of new anti-bacterial strategies.

  9. Retargeting a maize β-glucosidase to the vacuole--evidence from intact plants that zeatin-O-glucoside is stored in the vacuole.

    Science.gov (United States)

    Kiran, Nagavalli S; Benková, Eva; Reková, Alena; Dubová, Jaroslava; Malbeck, Jiří; Palme, Klaus; Brzobohatý, Břetislav

    2012-07-01

    Cytokinin (CK) activity is regulated by the complex interplay of their metabolism, transport, stability and cellular/tissue localization. O-glucosides of zeatin-type CKs are postulated to be storage and/or transport forms. Active CK levels are determined in part by their differential distribution of CK metabolites across different subcellular compartments. We have previously shown that overexpressing chloroplast-localized Zm-p60.1, a maize β-glucosidase capable of releasing active cytokinins from their O- and N3-glucosides, perturbs CK homeostasis in transgenic tobacco. We obtained tobacco (Nicotiana tabacum L., cv Petit Havana SR1) plants overexpressing a recombinant Zm-p60.1 that is targeted to the vacuole. The protein is correctly processed and localized to the vacuole. When grown on medium containing exogenous zeatin, transgenic seedlings rapidly accumulate fresh weight due to ectopic growths at the base of the hypocotyl. The presence of the enzyme in these ectopic structures is shown by histochemical staining. CK quantification reveals that these transgenic seedlings are unable to accumulate zeatin-O-glucoside to levels similar to those observed in the wild type. When crossed with tobacco overexpressing the zeatin-O-glucosyltransferase gene from Phaseolus, the vacuolar variant shows an almost complete reversion in the root elongation assay. This is the first evidence from intact plants that the vacuole is the storage organelle for CK O-glucosides and that they are available to attack by Zm-p60.1. We propose the use of Zm-p60.1 as a robust molecular tool that exploits the reversibility of O-glucosylation and enables delicate manipulations of active CK content at the cellular level.

  10. Treatment of Helicobacter pylori infection 2011.

    LENUS (Irish Health Repository)

    O'Connor, Anthony

    2012-02-01

    This article reviews the literature published pertaining to Helicobacter pylori eradication over the last year. The general perception among clinicians and academics engaged in research on H. pylori has been that eradication rates for first-line therapies are falling, although some data published this year have cast doubt on this. The studies published this year have therefore focussed on developing alternative strategies for the first-line eradication of H. pylori. In this regard, clear evidence now exists that both levofloxacin and bismuth are viable options for first-line therapy. The sequential and "concomitant" regimes have also been studied in new settings and may have a role in future algorithms also. In addition, data have emerged that the probiotic Saccharomyces boulardii may be a useful adjunct to antibiotic therapy. Other studies promote individualized therapies based on host polymorphisms, age, and other such demographic factors.

  11. Helicobacter pylori vaccine: from past to future.

    Science.gov (United States)

    Agarwal, Kanishtha; Agarwal, Shvetank

    2008-02-01

    Helicobacter pylori infection is highly prevalent worldwide and is an important cause of gastritis, peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma (MALToma), and gastric adenocarcinoma. Infection is usually acquired during childhood and tends to persist unless treated. Because eradication requires treatment with multidrug regimens, prevention of initial infection by a suitable vaccine is attractive. Although immunization with H pylori protein subunits has been encouraging in animals, similar vaccine trials in humans have shown adjuvant-related adverse effects and only moderate effectiveness. Newer immunization approaches (use of DNA, live vectors, bacterial ghosts, and microspheres) are being developed. Several questions about when and whom to vaccinate will need to be appropriately answered, and a cost-effective vaccine production and delivery strategy will have to be useful for developing countries. For this review, we searched MEDLINE using the Medical Subject Heading (MeSH) terms Helicobacter pylori and vaccines for articles in English from 1990 to 2007.

  12. Recent "omics" advances in Helicobacter pylori.

    Science.gov (United States)

    Berthenet, Elvire; Sheppard, Sam; Vale, Filipa F

    2016-09-01

    The development of high-throughput whole genome sequencing (WGS) technologies is changing the face of microbiology, facilitating the comparison of large numbers of genomes from different lineages of a same organism. Our aim was to review the main advances on Helicobacter pylori "omics" and to understand how this is improving our knowledge of the biology, diversity and pathogenesis of H. pylori. Since the first H. pylori isolate was sequenced in 1997, 510 genomes have been deposited in the NCBI archive, providing a basis for improved understanding of the epidemiology and evolution of this important pathogen. This review focuses on works published between April 2015 and March 2016. Helicobacter "omics" is already making an impact and is a growing research field. Ultimately these advances will be translated into a routine clinical laboratory setting in order to improve public health. © 2016 John Wiley & Sons Ltd.

  13. Toxin Plasmids of Clostridium perfringens

    Science.gov (United States)

    Li, Jihong; Adams, Vicki; Bannam, Trudi L.; Miyamoto, Kazuaki; Garcia, Jorge P.; Uzal, Francisco A.; Rood, Julian I.

    2013-01-01

    SUMMARY In both humans and animals, Clostridium perfringens is an important cause of histotoxic infections and diseases originating in the intestines, such as enteritis and enterotoxemia. The virulence of this Gram-positive, anaerobic bacterium is heavily dependent upon its prolific toxin-producing ability. Many of the ∼16 toxins produced by C. perfringens are encoded by large plasmids that range in size from ∼45 kb to ∼140 kb. These plasmid-encoded toxins are often closely associated with mobile elements. A C. perfringens strain can carry up to three different toxin plasmids, with a single plasmid carrying up to three distinct toxin genes. Molecular Koch's postulate analyses have established the importance of several plasmid-encoded toxins when C. perfringens disease strains cause enteritis or enterotoxemias. Many toxin plasmids are closely related, suggesting a common evolutionary origin. In particular, most toxin plasmids and some antibiotic resistance plasmids of C. perfringens share an ∼35-kb region containing a Tn916-related conjugation locus named tcp (transfer of clostridial plasmids). This tcp locus can mediate highly efficient conjugative transfer of these toxin or resistance plasmids. For example, conjugative transfer of a toxin plasmid from an infecting strain to C. perfringens normal intestinal flora strains may help to amplify and prolong an infection. Therefore, the presence of toxin genes on conjugative plasmids, particularly in association with insertion sequences that may mobilize these toxin genes, likely provides C. perfringens with considerable virulence plasticity and adaptability when it causes diseases originating in the gastrointestinal tract. PMID:23699255

  14. Recombinant Toxins for Cancer Treatment

    Science.gov (United States)

    Pastan, Ira; Fitzgerald, David

    1991-11-01

    Recombinant toxins target cell surface receptors and antigens on tumor cells. They kill by mechanisms different from conventional chemotherapy, so that cross resistance to conventional chemotherapeutic agents should not be a problem. Furthermore, they are not mutagens and should not induce secondary malignancies or accelerate progression of benign malignancies. They can be mass-produced cheaply in bacteria as homogeneous proteins. Either growth factor-toxin fusions or antibody-toxin fusions can be chosen, depending on the cellular target.

  15. Intracellular Trafficking of Bacterial Toxins

    OpenAIRE

    Williams, Jeffrey M.; Tsai, Billy

    2016-01-01

    Bacterial toxins often translocate across a cellular membrane to gain access into the host cytosol, modifying cellular components in order to exert their toxic effects. To accomplish this feat, these toxins traffic to a membrane penetration site where they undergo conformational changes essential to eject the toxin’s catalytic subunit into the cytosol. In this brief review, we highlight recent findings that elucidate both the trafficking pathways and membrane translocation mechanisms of toxin...

  16. Pore formation by Cry toxins.

    Science.gov (United States)

    Soberón, Mario; Pardo, Liliana; Muñóz-Garay, Carlos; Sánchez, Jorge; Gómez, Isabel; Porta, Helena; Bravo, Alejandra

    2010-01-01

    Bacillus thuringiensis (Bt) bacteria produce insecticidal Cry and Cyt proteins used in the biological control of different insect pests. In this review, we will focus on the 3d-Cry toxins that represent the biggest group of Cry proteins and also on Cyt toxins. The 3d-Cry toxins are pore-forming toxins that induce cell death by forming ionic pores into the membrane of the midgut epithelial cells in their target insect. The initial steps in the mode of action include ingestion of the protoxin, activation by midgut proteases to produce the toxin fragment and the interaction with the primary cadherin receptor. The interaction of the monomeric CrylA toxin with the cadherin receptor promotes an extra proteolytic cleavage, where helix alpha-1 of domain I is eliminated and the toxin oligomerization is induced, forming a structure of 250 kDa. The oligomeric structure binds to a secondary receptor, aminopeptidase N or alkaline phosphatase. The secondary receptor drives the toxin into detergent resistant membrane microdomains formingpores that cause osmotic shock, burst of the midgut cells and insect death. Regarding to Cyt toxins, these proteins have a synergistic effect on the toxicity of some Cry toxins. Cyt proteins are also proteolytic activated in the midgut lumen of their target, they bind to some phospholipids present in the mosquito midgut cells. The proposed mechanism of synergism between Cry and Cyt toxins is that Cyt1Aa function as a receptor for Cry toxins. The Cyt1A inserts into midgut epithelium membrane and exposes protein regions that are recognized by Cry11Aa. It was demonstrated that this interaction facilitates the oligomerization of Cry11Aa and also its pore formation activity.

  17. THE SYNERGY OF BACTERIAL TOXINS,

    Science.gov (United States)

    TOXINS AND ANTITOXINS, STRENGTH(PHYSIOLOGY), BACTERIA, CLOSTRIDIUM PERFRINGENS, CLOSTRIDIUM TETANI , CLOSTRIDIUM , STAPHYLOCOCCUS, ESCHERICHIA COLI, PROTEUS, ETIOLOGY, ANTIGENS, ANTIBODIES, AMINO ACIDS.

  18. Giardia lamblia and Helicobater pylori Coinfection

    Directory of Open Access Journals (Sweden)

    R Shafie

    2009-03-01

    Full Text Available "nBackground: Giardia lamblia and Helicobacter pylori are two flagellate microorganisms that grow in duodenum and stom­ach. The aim of this study was to evaluate the prevalence of them in patients with dyspepsia and other GI disorders. "nMethods: In this cross-sectional study, co-infection of above-mentioned agents was investigated in a group of 130 patients [me­dian age of 40 yr (range=11-79 including 76 males (58.8%] with dyspepsia using three methods of duodenal aspiration sam­ple, duodenal biopsy samples and evaluation of stool samples."nResults: : From 105 patients (59 males, 46 females, median age 40 years, range 11-79 entering this study from 3 hospitals, 4 patients (3.8% had G. lamblia and 61 patients (58% had H. pylori. All 4 patients infected by Giardia had also H. pylori infec­tion. Tenesmus (3 out of 4 patients was the most common symptom in patients with H. pylori infection (48 out of 61 pa­tients was reflux. Other symptoms in patients infected with both organisms (4 patients included diarrhea (2 cases, weight loss (2 cases, and loss of appetite (1 case but no report of vomiting."nConclusion: In patients co-infected with Giardia, H.pylori differentiation by physical examination is not possible. So in those patients with positive Rapid Urease Test (RUT, stool examination for Giardia detection is recommended. In addition, met­ronidazole (broad spectrum, anti-protozoal drug can be useful in H. pylori infection.

  19. Endoscopic faces of Helicobacter Pylori infection

    Directory of Open Access Journals (Sweden)

    Geanina Spulber

    2015-08-01

    Full Text Available Introduction: The infection caused by H. pylori appears secondary after a bacterial colonization of the stomach and the initial portion of the small bowel. H. pylori –infected patients can develop gastritis, peptic ulcer, stomach cancer or MALT lymphoma. H. pylori infection is defined by WHO like a type I carcinogen, its role in gastric carcinogenesis being supported by the greatest researchers. Objectives: In this study our purpose was to determine the endoscopic appearances in H. pylori infection quoted in medical literature until now and the frequency of their appearance in our group of interest. Materials and methods: In this study it was made an analytic study in which it was realized a retrospective cohort investigation at the Emergency Central Military and University Hospital “Dr. Carol Davila” Bucharest, gastroenterology branch –endoscopic department between 18.12.2012- 21.08.2013 on 1694 patients between 18 and 92 years old, with the medium age of 55 years old. As a diagnostic method for H. pylori infection we used superior digestive endoscopy during which were taken biopsies and it was made a fast urease test. Results: Regarding the variation of the endoscopic aspects at the population of study, we have found gastritis with all its aspects (which was Sidney classified in the biggest percentage meaning 59.3% of the cases, followed with a percentage of 18.8% by those without any endoscopic abnormality, and then in 10,33% of the cases we have found peptic ulcer. With a smaller percentage, under 10%, we have found duodenitis at 8.67% of this patients, and finally the most severe lesions represented by gastric cancer and lymphoma were found at 2,7% of the H.pylori infected patients.

  20. Helicobacter pylori: From Bench to Bedside

    Directory of Open Access Journals (Sweden)

    N Chiba

    1997-01-01

    Full Text Available With the exponential increase in research in the field of Helicobacter pylori a paradigm shift has occurred. It is now recognized that H pylori is a chronic infection of the stomach causing inflammation. Some patients remain asymptomatic, while others may develop dyspepsia, duodenal or gastric ulcer, gastric cancer or a mucosa-associated lymphoid tissue lymphoma. However, the role of H pylori in contributing to nonulcer dyspepsia or nonsteroidal anti-inflammatory drug gastropathy remains controversial. An effective vaccine against H pylori is years away. Major interest has focused on the questions "who should be investigated and therefore treated" and "what is the latest gold standard for eradication of H pylori"? In Europe, guidelines have been developed to help the practitioner answer these important questions. Canadian guidelines will soon be available. For persons with known peptic ulcer disease there should be unequivocal acceptance that the good clinical practice of eradicating H pylori will result in substantial savings in health care expenses. The original 'classical triple therapy' (bismuth, metronidazole and tetracycline [BMT] has now been surpassed by the combination of a proton pump inhibitor (PPI plus two antibiotics (metronidazole plus clarithromycin; amoxicillin plus clarithromycin; or amoxicillin plus metronidazole, each given twice a day for one week. In Canada, the regimen of omeprazole plus one antibiotic (amoxicillin or clarithromycin was approved recently but gives an eradication rate that is lower than the current target of 90%. According to the European (Mäastricht recommendations, if a single treatment attempt with PPI plus two antibiotics fails, PPI plus BMT is recommended.

  1. Helicobacter pylori-related immunoglobulins in sarcoidosis.

    Science.gov (United States)

    Herndon, Betty L; Vlach, Victoria; Dew, Michelle; Willsie, Sandra K

    2004-03-01

    The purpose of this study was to determine serum antibody titers against a common bacterial antigen, Helicobacter pylori (H. pylon), in subjects with sarcoidosis, comparing those titers to those present in a healthy population. With the approval of the Institutional Review Board of the University of Missouri-Kansas City, patients with sarcoidosis (pulmonary and extrapulmonary) who visited the Truman Medical Center-Hospital Hill pulmonary clinic were recruited to enter the study. A serum sample was frozen at -70 degrees C for later testing (n = 20). Specific information collected on subjects included corticosteroid use, use of histamine2 blockers and antacids, date of first diagnosis, and stage of sarcoidosis. Normal controls and demographically matched individuals who lacked pulmonary diseases, including sarcoidosis, were also recruited. Serum samples were processed as above. Antibody capture enzyme immunoassay was completed for H. pylori and urease antigens by serum dilution assay for each subject, from which titers for antigen-specific immunoglobulin (Ig)G and IgA were calculated. Nonspecific serum IgE was also measured. An increased incidence of high-titer IgG antibody directed against H. pylori antigens was found in subjects with sarcoidosis compared with controls. The sarcoidosis and control groups were significantly different with respect to IgG and IgA against H. pylori, both at p = .001. IgG directed against urease was also significantly different between sarcoidosis and control patients (p = .001), but IgA directed against urease was very low in all subjects and did not yield significant differences between groups. Specific H. pylori and urease IgG antibodies exceeded those expected in the population studied. The data suggest that in pulmonary sarcoidosis, the relationship of H. pylori and its products to sarcoid granuloma formation warrants further investigation.

  2. 3rd Brazilian consensus on Helicobacter pylori 3º Consenso Brasileiro para Estudo do Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Coelho

    Full Text Available Significant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.Os avanços significativos ocorridos desde o Segundo Consenso Brasileiro sobre H. pylori realizado em 2004, em São Paulo, justificam este terceiro consenso. O evento foi organizado pelo Núcleo Brasileiro para Estudo do Helicobacter, departamento da Federação Brasileira de Gastroenterologia, tendo sido realizado em Bento Gonçalves, RS, nos dias 12 a 15 de abril de 2011. Contou com a participação de 30 delegados provenientes das cinco regiões brasileiras e um convidado internacional, incluindo gastroenterologistas

  3. Effectiveness of vaccination with recombinant HpaA from Helicobacter pylori is influenced by host genetic background.

    Science.gov (United States)

    Sutton, Philip; Doidge, Christopher; Pinczower, Gideon; Wilson, John; Harbour, Stacey; Swierczak, Agnieszka; Lee, Adrian

    2007-07-01

    Several studies have explored the production and immunogenicity of HpaA as a potential protective antigen against Helicobacter pylori but little is known regarding its protective capabilities. We therefore evaluated the protective efficacy of recombinant HpaA (rHpaA) as a candidate vaccine antigen against H. pylori. To explore the impact of genetic diversity, inbred and outbred mice were prophylactically and therapeutically immunized with rHpaA adjuvanted with cholera toxin (CT). Prophylactic immunization induced a reduction in bacterial colonization in BALB/c and QS mice, but was ineffective in C57BL/6 mice, despite induction of antigen-specific antibodies. By contrast, therapeutic immunization was effective in all three strains of mice. Prophylactic immunization with CT-adjuvanted rHpaA was more effective when delivered via the nasal route than following intragastric delivery in BALB/c mice. However, HpaA-mediated protection was inferior to that induced by bacterial lysate. Hence, protective efficacy is inducible with vaccines containing HpaA, most relevantly shown in an outbred population of mice. The effectiveness of protection induced by HpaA antigen was influenced by host genetics and was less effective than lysate. HpaA therefore has potential for the development of effective immunization against H. pylori but this would probably entail the antigen to be one component of a multiantigenic vaccine.

  4. A pore-forming toxin enables Serratia a nonlytic egress from host cells.

    Science.gov (United States)

    Di Venanzio, Gisela; Lazzaro, Martina; Morales, Enrique S; Krapf, Darío; García Véscovi, Eleonora

    2017-02-01

    Several pathogens co-opt host intracellular compartments to survive and replicate, and they thereafter disperse progeny to prosper in a new niche. Little is known about strategies displayed by Serratia marcescens to defeat immune responses and disseminate afterwards. Upon invasion of nonphagocytic cells, Serratia multiplies within autophagosome-like vacuoles. These Serratia-containing vacuoles (SeCV) circumvent progression into acidic/degradative compartments, avoiding elimination. In this work, we show that ShlA pore-forming toxin (PFT) commands Serratia escape from invaded cells. While ShlA-dependent, Ca(2)(+) local increase was shown in SeCVs tight proximity, intracellular Ca(2)(+) sequestration prevented Serratia exit. Accordingly, a Ca(2)(+) surge rescued a ShlA-deficient strain exit capacity, demonstrating that Ca(2)(+) mobilization is essential for egress. As opposed to wild-type-SeCV, the mutant strain-vacuole was wrapped by actin filaments, showing that ShlA expression rearranges host actin. Moreover, alteration of actin polymerization hindered wild-type Serratia escape, while increased intracellular Ca(2)(+) reorganized the mutant strain-SeCV actin distribution, restoring wild-type-SeCV phenotype. Our results demonstrate that, by ShlA expression, Serratia triggers a Ca(2)(+) signal that reshapes cytoskeleton dynamics and ends up pushing the SeCV load out of the cell, in an exocytic-like process. These results disclose that PFTs can be engaged in allowing bacteria to exit without compromising host cell integrity.

  5. L-forms of H. Pylori

    Institute of Scientific and Technical Information of China (English)

    Ke-Xia Wang; Chao-Pin Li; Yu-Bao Cui; Ye Tian; Qing-Gui Yang

    2003-01-01

    AIM: To study the occurrence of L-forms of H. pyloriinfection in patients with peptic ulcers and its association with possible changes of cellular immune function in the patients.METHODS: Endoscopic biopsy specimens of gastric antrum and gastric corpus were taken from 228 patients with peptic ulcers and inoculated into Skirrow selective medium for H.pylorivegetative forms and special medium for H. pylori Lforms, followed by bacterial isolation and identification. And peripheral venous blood of the patients was taken to detect the percentage of CD3+, CD4+ and CD8+ with biotin-streptavidin (BSA) and the level of IL-2, IL-6 and IL-8 with ElISA.RESULTS: (1) The detection rates of H. pyloriL-forms and vegetative forms in the patients were 50.88 % (116/228)and 64.91 % (148/228) respectively, and the co-infection rate of H. pyloriL-forms and vegetative forms was 78.38 % (116/148). To be more exact, the detection rates of H. pylori L-forms in male and female patients were 57.04 % (77/135) and 41.94 % (39/93) respectively, and statistics found significant difference between them (P<0.05). Furthermore, the detection rates of H. pyloriL-forms in patients aged 14 years-, 30 years-, 40 years- and 50 years- were 31.91%(15/47), 42.86 % (24/56), 56.94 % (41/72) and 67.92 %(36/53) respectively, and there was significant difference between them (P<0.011). (2) The percentages of CD3+, CD4+,CD8+, the ratio of CD4+/CD8+, and the level of IL-2, IL-6,IL-8 in H. pylori-positive patients were (52.59±5.44) %,(35.51±5.74) %, (27.77±8.64) %, (1.56±0.51), (2.66±0.47)mg/L, (108.62±5.85) ng/L and (115.79±7.18) ng/Lrespectively, compared with those in H. pylori-negative patients, the percentages of CD3+, CD4+ and the ratio of CD4+/CD8+ decreased, but the level of IL-2, IL-6 increased, and the difference was significant (P<0.001-P<0.011).Moreover, the percentages of CD3+, CD4+, CD8+, the ratio of CD4+/CD8+, and the level of IL-2, IL-6, IL-8 in the patients with mixed infection of

  6. Antimicrobial Nanotherapeutics Against Helicobacter pylori Infection

    Science.gov (United States)

    Thamphiwatana, Soracha

    Helicobacter pylori (H. pylori) infection with its vast prevalence is responsible for various gastric diseases including gastritis, peptic ulcers, and gastric malignancy. While effective, current treatment regimens are challenged by a fast-declining eradication rate due to the increasing emergence of H. pylori strains resistant to existing antibiotics. Therefore, there is an urgent need to develop novel antibacterial strategies against H. pylori. The first area of this research, we developed a liposomal nanoformulation of linolenic acid (LipoLLA) and evaluated its bactericidal activity against resistant strains of H. pylori. We found that LipoLLA was effective in killing both spiral and dormant forms of the bacteria via disrupting bacterial membranes. LipoLLA eradicated all strains of the bacteria regardless of their antibiotic resistance status. Furthermore, the bacteria did not develop drug resistance toward LipoLLA. Our findings suggest that LipoLLA is a promising antibacterial nanotherapeutic to treat antibiotic-resistant H. pylori infection. The next step, we investigated the in vivo therapeutic potential of LipoLLA for the treatment of H. pylori infection. In vivo tests further confirmed that LipoLLA was able to kill H. pylori and reduce bacterial load in the mouse stomach. LipoLLA treatment was also shown to reduce the levels of proinflammatory cytokines including interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha, which were otherwise elevated due to the H. pylori infection. Finally, toxicity test demonstrated excellent biocompatibility of LipoLLA to normal mouse stomach. Collectively, results from this work indicate that LipoLLA is a promising, new, effective, and safe therapeutic agent for the treatment of H. pylori infection. The second area is stimuli-responsive liposomes development. By adsorbing small chitosan-modified gold nanoparticles (AuChi) onto the outer surface of liposomes, we show that at gastric pH the liposomes have

  7. Helicobacter pylori in humans: Where are we now?

    Directory of Open Access Journals (Sweden)

    Syed Arshad Hussain

    2014-01-01

    Full Text Available Helicobacter pylori has been associated with colonization of gastro duodenal mucosa of humans from millions of years. The main burden of the disese is in the developing countries, due to overcrowding and poor hygiene. If left untreated it leads to lot of sequlae from minor to sinister diseases over a period of time. The main challenges that remain are prevention of H. pylori-related diseases by effective treatment and screening procedures and development of a vaccine, which can address all these issues including beneficial aspects of H. pylori. The literature pertaining to different aspects of H. pylori were scrutinized from Pubmed. Material on clinical behavior, complications of chronic gastric involvement, and prevention besides role of H. pylori in nongastric diseases and the latest trends of management was collected for research and review. We continue to face many challenges.The prevention of cancer of the stomach, a worst sequlae of H. pylori continues to be a big challenge despite population screening and prevention surveys being underway in many countries. On the other hand continued scientific work has now unfolded involvement of H. pylori in extragastric diseases like cerebrovascular, cardiovascular, idiopathic thrombocytopenia, sideroblastic anemia, mental diseases, and collagen vascular diseases. In contrast, the beneficial effects of H. pylori with respect to allergic diseases and obesity are now clear. Moreover, problem of drug resistance for eradication of H. pylori has arisen for which novel treatments are being tried. Lactobacillus reuteri having anti H. pylori action is emerging as one of the promising treatment.

  8. Helicobacter pylori seropositivity and risk of lung cancer.

    Directory of Open Access Journals (Sweden)

    Jill Koshiol

    Full Text Available Lung cancer is the leading cause of cancer mortality worldwide. Helicobacter pylori (H. pylori is a risk factor for distal stomach cancer, and a few small studies have suggested that H. pylori may be a potential risk factor for lung cancer. To test this hypothesis, we conducted a study of 350 lung adenocarcinoma cases, 350 squamous cell carcinoma cases, and 700 controls nested within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC cohort of male Finnish smokers. Controls were one-to-one matched by age and date of baseline serum draw. Using enzyme-linked immunosorbent assays to detect immunoglobulin G antibodies against H. pylori whole-cell and cytotoxin-associated gene (CagA antigens, we calculated odds ratios (ORs and 95% confidence intervals (95% CIs for associations between H. pylori seropositivity and lung cancer risk using conditional logistic regression. H. pylori seropositivity was detected in 79.7% of cases and 78.5% of controls. After adjusting for pack-years and cigarettes smoked per day, H. pylori seropositivity was not associated with either adenocarcinoma (OR: 1.1, 95% CI: 0.75-1.6 or squamous cell carcinoma (OR: 1.1, 95% CI: 0.77-1.7. Results were similar for CagA-negative and CagA-positive H. pylori seropositivity. Despite earlier small studies suggesting that H. pylori may contribute to lung carcinogenesis, H. pylori seropositivity does not appear to be associated with lung cancer.

  9. Role of Helicobacter pylori in gastric cancer: Updates

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Helicobacter pylori (H. pylori ) infection is highly prevalentin human, affecting nearly half of the world'spopulation; however, infection remains asymptomaticin majority of population. During its co-existence withhumans, H. pylori has evolved various strategies tomaintain a mild gastritis and limit the immune responseof host. On the other side, presence of H. pylori is alsoassociated with increased risk for the development ofvarious gastric pathologies including gastric cancer (GC).A complex combination of host genetics, environmentalagents, and bacterial virulence factors are consideredto determine the susceptibility as well as the severityof outcome in a subset of individuals. GC is one of themost common cancers and considered as the third mostcommon cause of cancer related death worldwide. Manystudies had proved H. pylori as an important risk factorin the development of non-cardia GC. Although both H.pylori infection and GC are showing decreasing trendsin the developed world, they still remain a major threatto human population in the developing countries. Thecurrent review attempts to highlight recent progress inthe field of research on H. pylori induced GC and aimsto provide brief insight into H. pylori pathogenesis,the role of major virulence factors of H. pylori thatmodulates the host environment and transform thenormal gastric epithelium to neoplastic one. This reviewalso emphasizes on the mechanistic understanding ofhow colonization and various virulence attributes of H.pylori as well as the host innate and adaptive immuneresponses modulate the diverse signaling pathways thatleads to different disease outcomes including GC.

  10. Is duodenal biopsy appropriate in areas endemic for Helicobacter pylori?

    Science.gov (United States)

    Sahin, Abdurrahman; Cihangiroglu, Gulcin; Bilgic, Yilmaz; Calhan, Turan; Cengiz, Mustafa

    2017-01-01

    The primary reason for obtaining duodenal biopsy sample is to diagnose celiac disease. Helicobacter pylori (H. pylori) and drug injury are common causes of duodenitis. The aim of this retrospective study was to explore effects of H. pylori and drugs on duodenal mucosa. Duodenal biopsy samples of patients who underwent upper gastrointestinal endoscopy (UGIE) between February 2014 and December 2014 were retrospectively examined. Clinical symptoms, referral indications, endoscopic findings, H. pylori status, and drug history were recorded. Duodenal biopsy findings were compared based on presence of H. pylori and drug history. Of 2389 patients who underwent UGIE, 206 had duodenal biopsy. Eight patients (3.9%) were diagnosed with celiac disease. After excluding cases with celiac disease, 76 patients of remaining 198 patients (36.9%) had duodenal histopathological abnormality. H. pylori was found in 95 (47.9%) patients. Drug usage was less common (42%). Of patients who had histopathological duodenitis, 59% were H. pylori-infected. Rate of duodenitis was higher in H. pylori (+) group than in H. pylori (-) group (45% vs 27.1%; odds ratio, 2.4; 95% confidence interval, 1.3-4.4; p=0.005). There was no difference between groups regarding drug use in terms of histopathological duodenitis. H. pylori is the major contributor to duodenitis in high prevalence regions. Serological testing may be more appropriate before performing duodenal biopsy in patients with suspected celiac disease.

  11. Autophagy-related genes in Helicobacter pylori infection.

    Science.gov (United States)

    Tanaka, Shingo; Nagashima, Hiroyuki; Uotani, Takahiro; Graham, David Y; Yamaoka, Yoshio

    2017-06-01

    In vitro studies have shown that Helicobacter pylori (H. pylori) infection induces autophagy in gastric epithelial cells. However, prolonged exposure to H. pylori reduces autophagy by preventing maturation of the autolysosome. The alterations of the autophagy-related genes in H. pylori infection are not yet fully understood. We analyzed autophagy-related gene expression in H. pylori-infected gastric mucosa compared with uninfected gastric mucosa obtained from 136 Bhutanese volunteers with mild dyspeptic symptoms. We also studied single nucleotide polymorphisms (SNPs) of autophagy-related gene in 283 Bhutanese participants to identify the influence on susceptibility to H. pylori infection. Microarray analysis of 226 autophagy-related genes showed that 16 genes were upregulated (7%) and nine were downregulated (4%). We used quantitative reverse transcriptase polymerase chain reaction to measure mRNA levels of the downregulated genes (ATG16L1, ATG5, ATG4D, and ATG9A) that were core molecules of autophagy. ATG16L1 and ATG5 mRNA levels in H. pylori-positive specimens (n=86) were significantly less than those in H. pylori-negative specimens (n=50). ATG16L1 mRNA levels were inversely related to H. pylori density. We also compared SNPs of ATG16L1 (rs2241880) among 206 H. pylori-positive and 77 H. pylori-negative subjects. The odds ratio for the presence of H. pylori in the GG genotype was 0.40 (95% CI: 0.18-0.91) relative to the AA/AG genotypes. Autophagy-related gene expression profiling using high-throughput microarray analysis indicated that downregulation of core autophagy machinery genes may depress autophagy functions and possibly provide a better intracellular habit for H. pylori in gastric epithelial cells. © 2017 John Wiley & Sons Ltd.

  12. Botulinum toxin: bioweapon & magic drug.

    Science.gov (United States)

    Dhaked, Ram Kumar; Singh, Manglesh Kumar; Singh, Padma; Gupta, Pallavi

    2010-11-01

    Botulinum neurotoxins, causative agents of botulism in humans, are produced by Clostridium botulinum, an anaerobic spore-former Gram positive bacillus. Botulinum neurotoxin poses a major bioweapon threat because of its extreme potency and lethality; its ease of production, transport, and misuse; and the need for prolonged intensive care among affected persons. A single gram of crystalline toxin, evenly dispersed and inhaled, can kill more than one million people. The basis of the phenomenal potency of botulinum toxin is enzymatic; the toxin is a zinc proteinase that cleaves neuronal vesicle associated proteins responsible for acetylcholine release into the neuromuscular junction. As a military or terrorist weapon, botulinum toxin could be disseminated via aerosol or by contamination of water or food supplies, causing widespread casualties. A fascinating aspect of botulinum toxin research in recent years has been development of the most potent toxin into a molecule of significant therapeutic utility . It is the first biological toxin which is licensed for treatment of human diseases. In the late 1980s, Canada approved use of the toxin to treat strabismus, in 2001 in the removal of facial wrinkles and in 2002, the FDA in the United States followed suit. The present review focuses on both warfare potential and medical uses of botulinum neurotoxin.

  13. Myelin vacuolation, optic neuropathy and retinal degeneration after closantel overdosage in sheep and in a goat.

    Science.gov (United States)

    van der Lugt, J J; Venter, I

    2007-01-01

    Toxicity of closantel, a halogenated salicylanilide anthelmintic, is described in 11 sheep and a goat, humanely killed 4-70 days after accidental overdosage. Status spongiosis of the cerebrum and cerebellum was present, its severity decreasing with time after treatment. Ultrastructurally, vacuoles in the cerebral white matter were seen to be intramyelinic due to splitting of myelin lamellae at the intraperiod lines, indicating myelin oedema. In the optic nerves, Wallerian degeneration and eventual fibrosis and atrophy of the nerves followed myelin vacuolation. Lesions in the optic nerves were particularly advanced in the intracanalicular portion, indicating a compressive neuropathy within the optic canal. Acute retinal lesions consisted of papilloedema, necrosis of the outer retinal layers (especially the photoreceptor layer), and retinal separation in tapetal and non-tapetal areas. In more chronic cases, the outer nuclear layer was diffusely attenuated and generally reduced to a single row of cells.

  14. Vacuole/extravacuole distribution of soluble protease in Hippeastrum petal and Triticum leaf protoplasts

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.J.; Mulready, P.; Cutt, J.

    1981-11-01

    The subcellular distribution of soluble protease in anthesis-stage, anthocyanin-containing Hippeastrum cv. Dutch Red Hybrid petal protoplasts has been reevaluated and that of Triticum aestivum L. var. Red Coat leaf protoplasts determined using /sup 125/I-fibrin as a protease substrate and improved methods for protoplast and vacuole volume estimation. Results indicate that about 20% of the Hippeastrum petal-soluble protease and about 90% of the wheat leaf-soluble protease can be assigned to the vacuole. Protoplast isolation enzyme labeled with /sup 125/I has been used to assess the efficiency of removing isolation enzyme from protoplasts by repeated washing and by separation of protoplasts from debris using density centrifugation. Results of these studies suggest that protoplasts prepared by both methods retain low levels of isolation enzyme. However, when protoplasts prepared by either method were lysed with washing medium lacking osmoticum, little isolation enzyme contaminated the lysates.

  15. Organization of the cytoplasmic reticulum in the central vacuole of parenchyma cells in Allium cepa L.

    Directory of Open Access Journals (Sweden)

    Tomasz J. Wodzicki

    2015-01-01

    Full Text Available An elaborate and complex cytoplasmic reticulum composed of fine filaments and lamellae ranging from 0.1 to 4 microns in size is revealed by viewing the central vacuole of onion bulb parenchyma cells with the scanning election microscope. The larger cytoplasmic strands, visible with the light microscope, are composed of numerous smaller filaments (some tubular which might explain the observed bidirectional movement of particles in these larger strands. The finely divided cytoplasmic network of filaments is continuous with the parietal cytoplasm inclosing the vacuolar sap. In these highly vacuolated cells the mass of the protoplast is in the form of an intravacuolar reticulum immersed in the cell sap. The probable significance of the vacuolar sap in relation to physiological processes of the cell is discussed.

  16. Catechins and Sialic Acid Attenuate Helicobacter pylori-Triggered Epithelial Caspase-1 Activity and Eradicate Helicobacter pylori Infection

    Directory of Open Access Journals (Sweden)

    Jyh-Chin Yang

    2013-01-01

    Full Text Available The inflammasome/caspase-1 signaling pathway in immune cells plays a critical role in bacterial pathogenesis; however, the regulation of this pathway in the gastric epithelium during Helicobacter pylori infection is yet to be elucidated. Here, we investigated the effect of catechins (CAs, sialic acid (SA, or combination of CA and SA (CASA on H. pylori-induced caspase-1-mediated epithelial damage, as well as H. pylori colonization in vitro (AGS cells and in vivo (BALB/c mice. Our results indicate that the activity of caspase-1 and the expression of its downstream substrate IL-1β were upregulated in H. pylori-infected AGS cells. In addition, we observed increased oxidative stress, NADPH oxidase gp91phox, CD68, caspase-1/IL-1β, and apoptosis, but decreased autophagy, in the gastric mucosa of H. pylori-infected mice. We have further demonstrated that treatment with CASA led to synergistic anti-H. pylori activity and was more effective than treatment with CA or SA alone. In particular, treatment with CASA for 10 days eradicated H. pylori infection in up to 95% of H. pylori-infected mice. Taken together, we suggest that the pathogenesis of H. pylori involves a gastric epithelial inflammasome/caspase-1 signaling pathway, and our results show that CASA was able to attenuate this pathway and effectively eradicate H. pylori infection.

  17. An Acanthamoeba castellanii metacaspase associates with the contractile vacuole and functions in osmoregulation.

    Science.gov (United States)

    Saheb, Entsar; Trzyna, Wendy; Bush, John

    2013-03-01

    Acanthamoeba castellanii is a free-living protozoan. Some strains are opportunistic pathogens. A type-I metacaspase was identified in A. castellanii (Acmcp) and was shown to be expressed through the encystation process. The model organism, Dictyostelium discoideum, has been used here as a model for studying these caspase-like proteins. Separate cell lines expressing a GFP-tagged version of the full length Acmcp protein, as well as a deletion proline region mutant of Acmcp protein (GFP-Acmcp-dpr), have been introduced into D. discoideum. Both mutants affect the cellular metabolism, characterized by an increase in the growth rate. Microscopic imaging revealed an association between Acmcp and the contractile vacuole system in D. discoideum. The treatment of cells with selected inhibitors in different environments added additional support to these findings. This evidence shows that Acmcp plays an important role in contractile vacuole regulation and mediated membrane trafficking in D. discoideum. Additionally, the severe defect in contractile vacuole function in GFP-Acmcp-dpr mutant cells suggests that the proline-rich region in Acmcp has an essential role in binding this protein with other partners to maintain this process. Furthermore, Yeast two-hybrid system identified there are weak interactions of the Dictyostelium contractile vacuolar proteins, including Calmodulin, RabD, Rab11 and vacuolar proton ATPase, with Acmcp protein. Taken together, our findings suggest that A. castellanii metacaspase associate with the contractile vacuole and have an essential role in cell osmoregulation, which contributes to its attractiveness as a possible target for treatment therapies against A. castellanii infection.

  18. Neospora caninum Recruits Host Cell Structures to Its Parasitophorous Vacuole and Salvages Lipids from Organelles.

    Science.gov (United States)

    Nolan, Sabrina J; Romano, Julia D; Luechtefeld, Thomas; Coppens, Isabelle

    2015-05-01

    Toxoplasma gondii and Neospora caninum, which cause the diseases toxoplasmosis and neosporosis, respectively, are two closely related apicomplexan parasites. They have similar heteroxenous life cycles and conserved genomes and share many metabolic features. Despite these similarities, T. gondii and N. caninum differ in their transmission strategies and zoonotic potential. Comparative analyses of the two parasites are important to identify the unique biological features that underlie the basis of host preference and pathogenicity. T. gondii and N. caninum are obligate intravacuolar parasites; in contrast to T. gondii, events that occur during N. caninum infection remain largely uncharacterized. We examined the capability of N. caninum (Liverpool isolate) to interact with host organelles and scavenge nutrients in comparison to that of T. gondii (RH strain). N. caninum reorganizes the host microtubular cytoskeleton and attracts endoplasmic reticulum (ER), mitochondria, lysosomes, multivesicular bodies, and Golgi vesicles to its vacuole though with some notable differences from T. gondii. For example, the host ER gathers around the N. caninum parasitophorous vacuole (PV) but does not physically associate with the vacuolar membrane; the host Golgi apparatus surrounds the N. caninum PV but does not fragment into ministacks. N. caninum relies on plasma lipoproteins and scavenges cholesterol from NPC1-containing endocytic organelles. This parasite salvages sphingolipids from host Golgi Rab14 vesicles that it sequesters into its vacuole. Our data highlight a remarkable degree of conservation in the intracellular infection program of N. caninum and T. gondii. The minor differences between the two parasites related to the recruitment and rearrangement of host organelles around their vacuoles likely reflect divergent evolutionary paths.

  19. Interorganelle interactions and inheritance patterns of nuclei and vacuoles in budding yeast meiosis.

    Science.gov (United States)

    Tsai, I-Ting; Lin, Jyun-Liang; Chiang, Yi-Hsuan; Chuang, Yu-Chien; Liang, Shu-Shan; Chuang, Chi-Ning; Huang, Tzyy-Nan; Wang, Ting-Fang

    2014-02-01

    Many of the mechanisms by which organelles are inherited by spores during meiosis are not well understood. Dramatic chromosome motion and bouquet formation are evolutionarily conserved characteristics of meiotic chromosomes. The budding yeast bouquet genes (NDJ1, MPS3, CSM4) mediate these movements via telomere attachment to the nuclear envelope (NE). Here, we report that during meiosis the NE is in direct contact with vacuoles via nucleus-vacuole junctions (NVJs). We show that in meiosis NVJs are assembled through the interaction of the outer NE-protein Nvj1 and the vacuolar membrane protein Vac8. Notably, NVJs function as diffusion barriers that exclude the nuclear pore complexes, the bouquet protein Mps3 and NE-tethered telomeres from the outer nuclear membrane and nuclear ER, resulting in distorted NEs during early meiosis. An increase in NVJ area resulting from Nvj1-GFP overexpression produced a moderate bouquet mutant-like phenotype in wild-type cells. NVJs, as the vacuolar contact sites of the nucleus, were found to undergo scission alongside the NE during meiotic nuclear division. The zygotic NE and NVJs were partly segregated into 4 spores. Lastly, new NVJs were also revealed to be synthesized de novo to rejoin the zygotic NE with the newly synthesized vacuoles in the mature spores. In conclusion, our results revealed that budding yeast nuclei and vacuoles exhibit dynamic interorganelle interactions and different inheritance patterns in meiosis, and also suggested that nvj1Δ mutant cells may be useful to resolve the technical challenges pertaining to the isolation of intact nuclei for the biochemical study of meiotic nuclear proteins.

  20. Determination of Glutathione and Its Redox Status in Isolated Vacuoles of Red Beetroot Cells

    Directory of Open Access Journals (Sweden)

    E.V. Pradedova

    2016-02-01

    Full Text Available The glutathione of the red beetroot vacuoles (Beta vulgaris L. was measured using three well-known methods: the spectrofluorimetric method with orthophthalic aldehyde (OPT; the spectrophotometric method with 5.5'-dithiobis-2-nitrobenzoic acid (DTNB; the high-performance liquid chromatography (HPLC. The content of reduced (GSH and oxidized glutathione (GSSG differed depending on the research method. With OPT the concentration of glutathione was: GSH – 0.059 µmol /mg protein; GSSG – 0.019 µmol/mg protein and total glutathione (GSHtotal – 0.097 µmol/mg protein. In the case of determining with DTNB the concentration of glutathione was: GSH – 0.091 µmol/mg protein; GSSG – 0.031 µmol/mg protein; GSHtotal – 0.153 µmol/mg protein. HPLC-defined concentration of glutathione was lower: GSH – 0.039 µmol/mg protein; GSSG – 0.007 µmol/mg protein; GSHtotal – 0.053 µmol/mg protein. Redox ratio of GSH/GSSG was also dependent on the method of determination: with OPT – 3.11; with DTNB – 2.96 and HPLC – 5.57. Redox ratio of glutathione in vacuoles was much lower than the tissue extracts of red beetroot, which, depending on the method of determination, was: 7.23, 7.16 and 9.22. The results showed the vacuoles of red beetroot parenchyma cells contain glutathione. Despite the low value of the redox ratio GSH/GSSG, in vacuoles the pool of reduced glutathione prevailed over the pool of oxidized glutathione.

  1. Oculopharyngeal Weakness, Hypophrenia, Deafness, and Impaired Vision: A Novel Autosomal Dominant Myopathy with Rimmed Vacuoles

    Institute of Scientific and Technical Information of China (English)

    Ting Chen; Xiang-Hui Lu; Hui-Fang Wang; Rui Ban; Hua-Xu Liu; Qiang Shi; Qian Wang

    2016-01-01

    Background:Myopathies with rimmed vacuoles are a heterogeneous group of muscle disorders with progressive muscle weakness and varied clinical manifestations but similar features in muscle biopsies.Here,we describe a novel autosomal dominant myopathy with rimmed vacuoles in a large family with 11 patients of three generations affected.Methods:A clinical study including family history,obstetric,pediatric,and development history was recorded.Clinical examinations including physical examination,electromyography (EMG),serum creatine kinase (CK),bone X-rays,and brain magnetic resonance imaging (MRI) were performed in this family.Open muscle biopsies were performed on the proband and his mother.To find the causative gene,the whole-exome sequencing was carried out.Results:Disease onset was from adolescence to adulthood,but the affected patients of the third generation presented an earlier onset and more severe clinical manifestations than the older generations.Clinical features were characterized as dysarthria,dysphagia,external ophthalmoplegia,limb weakness,hypophrenia,deafness,and impaired vision.However,not every patient manifested all symptoms.Serum CK was mildly elevated and EMG indicated a myopathic pattern.Brain MRI showed cerebellum and brain stem mildly atrophy.Rimmed vacuoles and inclusion bodies were observed in muscle biopsy.The whole-exome sequencing was performed,but the causative gene has not been found.Conclusions:We reported a novel autosomal dominant myopathy with rimmed vacuoles characterized by dysarthria,dysphagia,external ophthalmoplegia,limb weakness,hypophrenia,deafness,and impaired vision,but the causative gene has not been found and needs further study.

  2. Mitochondrial Extrusion through the Cytoplasmic Vacuoles during Cell Death*S⃞

    OpenAIRE

    Nakajima, Akihito; Kurihara, Hidetake; Yagita, Hideo; Okumura, Ko; Nakano, Hiroyasu

    2008-01-01

    Under various conditions, noxious stimuli damage mitochondria, resulting in mitochondrial fragmentation; however, the mechanisms by which fragmented mitochondria are eliminated from the cells remain largely unknown. Here we show that cytoplasmic vacuoles originating from the plasma membrane engulfed fragmented mitochondria and subsequently extruded them into the extracellular spaces in undergoing acute tumor necrosis factor α-induced cell death in a caspase-dependent f...

  3. Large nuclear vacuoles in spermatozoa negatively affect pregnancy rate in IVF cycles.

    Science.gov (United States)

    Ghazali, Shahin; Talebi, Ali Reza; Khalili, Mohammad Ali; Aflatoonian, Abbas; Esfandiari, Navid

    2015-07-01

    Recently, motile sperm organelle morphology examination (MSOME) criteria as a new real time tool for evaluation of spermatozoa in intracytoplasmic sperm injection (ICSI) cycles has been considered. The aim was to investigate the predictive value of MSOME in in vitro fertilization (IVF) in comparison to ICSI cycles and evaluation of the association between MSOME parameters and traditional sperm parameters in both groups. This is a cross sectional prospective analysis of MSOME parameters in IVF (n=31) and ICSI cycles (n=35). MSOME parameters were also evaluated as the presence of vacuole (none, small, medium, large or mix); head size (normal, small or large); cytoplasmic droplet; head shape and acrosome normality. In sub-analysis, MSOME parameters were compared between two groups with successful or failed clinical pregnancy in each group. In IVF group, the rate of large nuclear vacuole showed significant increase in failed as compared to successful pregnancies (13.81±9.7vs7.38±4.4, respectively, p=0.045) while MSOME parameters were the same between successful and failed pregnancies in ICSI group. Moreover, a negative correlation was noticed between LNV and sperm shape normalcy. In ICSI group, a negative correlation was established between cytoplasmic droplet and sperm shape normalcy. In addition, there was a positive correlation between sperm shape normalcy and non-vacuolated spermatozoa. The high rate of large nuclear vacuoles in sperm used in IVF cycles with failed pregnancies confirms that MSOME, is a helpful tool for fine sperm morphology assessment, and its application may enhance the assisted reproduction technology success rates.

  4. Large nuclear vacuoles in spermatozoa negatively affect pregnancy rate in IVF cycles

    Directory of Open Access Journals (Sweden)

    Shahin Ghazali

    2015-07-01

    Full Text Available Background: Recently, motile sperm organelle morphology examination (MSOME criteria as a new real time tool for evaluation of spermatozoa in intracytoplasmic sperm injection (ICSI cycles has been considered. Objective: The aim was to investigate the predictive value of MSOME in in vitro fertilization (IVF in comparison to ICSI cycles and evaluation of the association between MSOME parameters and traditional sperm parameters in both groups. Materials and Methods: This is a cross sectional prospective analysis of MSOME parameters in IVF (n=31 and ICSI cycles (n=35. MSOME parameters were also evaluated as the presence of vacuole (none, small, medium, large or mix; head size (normal, small or large; cytoplasmic droplet; head shape and acrosome normality. In sub-analysis, MSOME parameters were compared between two groups with successful or failed clinical pregnancy in each group. Results: In IVF group, the rate of large nuclear vacuole showed significant increase in failed as compared to successful pregnancies (13.81±9.7vs7.38±4.4, respectively, p=0.045 while MSOME parameters were the same between successful and failed pregnancies in ICSI group. Moreover, a negative correlation was noticed between LNV and sperm shape normalcy. In ICSI group, a negative correlation was established between cytoplasmic droplet and sperm shape normalcy. In addition, there was a positive correlation between sperm shape normalcy and non-vacuolated spermatozoa. Conclusion: The high rate of large nuclear vacuoles in sperm used in IVF cycles with failed pregnancies confirms that MSOME, is a helpful tool for fine sperm morphology assessment, and its application may enhance the assisted reproduction technology success rates.

  5. Diagnosis and treatment of Helicobacter pylori infection

    DEFF Research Database (Denmark)

    Bytzer, Peter; Dahlerup, Jens Frederik; Eriksen, Jens Ravn

    2011-01-01

    National Danish guidelines for the diagnosis and treatment of Helicobacter pylori (Hp) infection have been approved by the Danish Society for Gastroenterology. All patients with peptic ulcer disease, gastric cancer, and MALT lymphoma should be tested for Hp. We also recommend testing in first...

  6. Helicobacter pylori infection - recent developments in diagnosis.

    Science.gov (United States)

    Lopes, Ana Isabel; Vale, Filipa F; Oleastro, Mónica

    2014-07-28

    Considering the recommended indications for Helicobacter pylori (H. pylori) eradication therapy and the broad spectrum of available diagnostic methods, a reliable diagnosis is mandatory both before and after eradication therapy. Only highly accurate tests should be used in clinical practice, and the sensitivity and specificity of an adequate test should exceed 90%. The choice of tests should take into account clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy and the availability of the tests. This review concerns some of the most recent developments in diagnostic methods of H. pylori infection, namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H. pylori infection, such as magnifying endoscopy techniques and chromoendoscopy. In addition, the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups. Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test. Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance.

  7. Helicobacter pylori infection - recent developments in diagnosis

    Science.gov (United States)

    Lopes, Ana Isabel; Vale, Filipa F; Oleastro, Mónica

    2014-01-01

    Considering the recommended indications for Helicobacter pylori (H. pylori) eradication therapy and the broad spectrum of available diagnostic methods, a reliable diagnosis is mandatory both before and after eradication therapy. Only highly accurate tests should be used in clinical practice, and the sensitivity and specificity of an adequate test should exceed 90%. The choice of tests should take into account clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy and the availability of the tests. This review concerns some of the most recent developments in diagnostic methods of H. pylori infection, namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H. pylori infection, such as magnifying endoscopy techniques and chromoendoscopy. In addition, the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups. Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test. Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance. PMID:25071324

  8. Effects of Community Screening for Helicobacter pylori

    DEFF Research Database (Denmark)

    Bomme, Maria; Hansen, Jane Møller; Wildner-Christensen, Mette

    2017-01-01

    BACKGROUND & AIMS: Helicobacter pylori (Hp) eradication improves the prognosis of peptic ulcer disease (PUD), dyspepsia, and possibly gastric cancer. Hp screening tests are accurate and eradication therapy is effective. Hp population screening seems attractive. The aim of this study was to evaluate...

  9. Gastric angiogenesis and Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    I. D. Pousa

    Full Text Available The formation of new blood vessels seen in conditions commonly associated with Helicobacter pylori (H. pylori infection, including gastritis, peptic ulcer, and gastric carcinoma, prompts consideration of a potential relationship between mucosal colonization by this organism and the angiogenic process. H. pylori directly or indirectly damages endothelial cells, which induces a number of changes in the microvasculature of the gastric mucosa. In H. pylori-associated conditions, that is, in gastritis, peptic ulcer and gastric carcinoma, there is an increased concentration of angiogenic factors, and subsequently a formation of new blood vessels. However, this early angiogenesis -which is activated to repair the gastric mucosa- is subsequently inhibited in patients with peptic ulcer, and ulcer healing is thus delayed. This may be due to the antiproliferative action of this organism on endothelial cells. While the angiogenic process becomes inhibited in infected patients with peptic ulcer, it remains seemingly active in those with gastritis or gastric cancer. This fact is in support of the notion suggested by various studies that peptic ulcer and gastric cancer are mutually excluding conditions. In the case of gastric cancer, neoangiogenesis would enhance nutrient and oxygen supply to cancer cells, and thus tumor growth and metastatic spread.

  10. Natural transformation and recombination in Helicobacter pylori

    NARCIS (Netherlands)

    Smeets, L.C.

    2007-01-01

    Bacteriën kennen geen geslachtelijke voortplanting, ze hebben altijd één “ouder” in plaats van twee. Ze kunnen dus tijdens de voortplanting niet kruisen. Om toch erfelijke eigenschappen te kunnen uitwisselen hebben ze andere methoden. De maagbacterie Helicobacter pylori kan dit bijvoorbeeld doen doo

  11. Mutations that affect vacuole biogenesis inhibit proliferation of the endoplasmic reticulum in Saccharomyces cerevisiae.

    Science.gov (United States)

    Koning, Ann J; Larson, Lynnelle L; Cadera, Emily J; Parrish, Mark L; Wright, Robin L

    2002-04-01

    In yeast, increased levels of the sterol biosynthetic enzyme, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase isozyme, Hmg1p, induce assembly of nuclear-associated ER membranes called karmellae. To identify additional genes involved in karmellae assembly, we screened temperature-sensitive mutants for karmellae assembly defects. Two independently isolated, temperature-sensitive strains that were also defective for karmellae biogenesis carried mutations in VPS16, a gene involved in vacuolar protein sorting. Karmellae biogenesis was defective in all 13 other vacuole biogenesis mutants tested, although the severity of the karmellae assembly defect varied depending on the particular mutation. The hypersensitivity of 14 vacuole biogenesis mutants to tunicamycin was well correlated with pronounced defects in karmellae assembly, suggesting that the karmellae assembly defect reflected alteration of ER structure or function. Consistent with this hypothesis, seven of eight mutations causing defects in secretion also affected karmellae assembly. However, the vacuole biogenesis mutants were able to proliferate their ER in response to Hmg2p, indicating that the mutants did not have a global defect in the process of ER biogenesis.

  12. [Effect of acetylcholine and acetylcholinesterase on the activity of contractile vacuole of Amoeba proteus].

    Science.gov (United States)

    Bagrov, Ia Iu; Manusova, N B

    2011-01-01

    Acetylcholine (ACh, 1 microM) stimulates activity of the contractile vacuole of proteus. The effect of ACh is not mimicked by its analogs which are not hydrolyzed by acetylcholinesterase (AChE), i. e., carbacholine and 5-methylfurmethide. The effect of ACh is not sensitive to the blocking action of M-cholinolytics, atropine and mytolone, but is suppressed by N-cholinolytic, tubocurarine. The inhibitors of AChE, eserine (0.01 microM) and armine (0.1 microM), suppress the effect of ACh on amoeba contractile vacuole. ACh does not affect activation of contractile vacuole induced by arginine-vasopressin (1 microM), but it blocks such effect of opiate receptors agonist, dynorphin A1-13 (0.01 microM). This effect of ACh is also suppressed by the inhibitors of AChE. These results suggest that, in the above-described effects of ACh, AChE acts not as an antagonist, but rather as a synergist.

  13. Vacuolization and apoptosis induced by nano-selenium in HeLa cell line

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Selenium(Se),a potential drug candidate for cancer prevention,has a special property:Its nutritional dosage and tolerable upper intake level appear in a narrow range,while the therapeutic use of this mineral may depend on a higher body intake level.Nano-selenium(nano-Se) particles,however,preserve the selenium element’s low toxicity characteristic but give a high biochemical activity effect of selenium compounds.In the present study different morphologies of synthesized nano-Se were evaluated concerning its anti-proliferation and apoptosis-inducing effect.Then nano-Se(sphere) were picked out to investigate its influence on two significant events involved in apoptosis,cell cycle arrest and mitochondrial membrane potential disruption.Furthermore,massive vacuolization of HeLa cells treated by nano-Se(sphere) was observed and more methods were used to measure the level of vacuolization.Such vacuolization needs energy supply and has been demonstrated to be related to Se endocytosis.These results suggest a possible mechanism to trigger apoptosis initiation.

  14. Vacuole import and degradation pathway:Insights into a specialized autophagy pathway

    Institute of Scientific and Technical Information of China (English)

    Abbas; A; Alibhoy; Hui-Ling; Chiang

    2011-01-01

    Glucose deprivation induces the synthesis of pivotagluconeogenic enzymes such as fructose-1,6-bisphos-phatase, malate dehydrogenase, phosphoenolpyruvatecarboxykinase and isocitrate lyase in Saccharomycescerevisiae. However, following glucose replenishment,these gluconeogenic enzymes are inactivated and de-graded. Studies have characterized the mechanismsby which these enzymes are inactivated in response toglucose. The site of degradation of these proteins hasalso been ascertained to be dependent on the dura-tion of starvation. Glucose replenishment of short-termstarved cells results in these proteins being degradedin the proteasome. In contrast, addition of glucose tocells starved for a prolonged period results in theseproteins being degraded in the vacuole. In the vacuoledependent pathway, these proteins are sequestered inspecialized vesicles termed vacuole import and degra-dation (Vid). These vesicles converge with the endo-cytic pathway and deliver their cargo to the vacuolefor degradation. Recent studies have identified thatinternalization, as mediated by actin polymerization, isessential for delivery of cargo proteins to the vacuolefor degradation. In addition, components of the targetof rapamycin complex 1 interact with cargo proteins during glucose starvation. Furthermore, Tor1p dissoci-ates from cargo proteins following glucose replenish-ment. Future studies will be needed to elaborate on the importance of internalization at the plasma membrane and the subsequent import of cargo proteins into Vid vesicles in the vacuole dependent degradation pathway.

  15. The vacuole model: new terms in the second order deflection of light

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Amrita; Nandi, Kamal K. [Department of Mathematics, University of North Bengal, Raja Rammohunpur, Siliguri 734 013 (India); Garipova, Guzel M. [Department of Theoretical Physics, Sterlitamak State Pedagogical Academy, 49, Lenin Street, Sterlitamak 453103 (Russian Federation); Laserra, Ettore [DMI, Università di Salerno, Via Ponte Don Melillo, 84084 Fisciano, Salerno (Italy); Bhadra, Arunava, E-mail: amrita852003@yahoo.co.in, E-mail: goldberg144@gmail.com, E-mail: elaserra@unisa.it, E-mail: aru_bhadra@yahoo.com, E-mail: kamalnandi1952@yahoo.co.in [High Energy and Cosmic Ray Research Center, University of North Bengal, Raja Rammohunpur, Siliguri 734 013 (India)

    2011-02-01

    The present paper is an extension of a recent work (Bhattacharya et al. 2010) to the Einstein-Strauss vacuole model with a cosmological constant, where we work out the light deflection by considering perturbations up to order M{sup 3} and confirm the light bending obtained previously in their vacuole model by Ishak et al. (2008). We also obtain another local coupling term −5πM{sup 2}Λ/8 related to Λ, in addition to the one obtained by Sereno (2008, 2009). We argue that the vacuole method for light deflection is exclusively suited to cases where the cosmological constant Λ disappears from the path equation. However, the original Rindler-Ishak method (2007) still applies even if a certain parameter γ of Weyl gravity does not disappear. Here, using an alternative prescription, we obtain the known term −γR/2, as well as another new local term 3πγM/2 between M and γ. Physical implications are compared, where we argue that the repulsive term −γR/2 can be masked by the Schwarzschild term 2M/R in the halo regime supporting attractive property of the dark matter.

  16. Ergosteryl-β-glucosidase (Egh1) involved in sterylglucoside catabolism and vacuole formation in Saccharomyces cerevisiae.

    Science.gov (United States)

    Watanabe, Takashi; Tani, Motohiro; Ishibashi, Yohei; Endo, Ikumi; Okino, Nozomu; Ito, Makoto

    2015-10-01

    Sterylglucosides (SGs) are composed of a glucose and sterol derivatives, and are distributed in fungi, plants and mammals. We recently identified EGCrP1 and EGCrP2 (endoglycoceramidase-related proteins 1 and 2) as a β-glucocerebrosidase and steryl-β-glucosidase, respectively, in Cryptococcus neoformans. We herein describe an EGCrP2 homologue (Egh1; ORF name, Yir007w) involved in SG catabolism in Saccharomyces cerevisiae. The purified recombinant Egh1 hydrolyzed various β-glucosides including ergosteryl β-glucoside (EG), cholesteryl β-glucoside, sitosteryl β-glucoside, para-nitrophenyl β-glucoside, 4-methylumberifellyl β-glucoside and glucosylceramide. The disruption of EGH1 in S. cerevisiae BY4741 (egh1Δ) resulted in the accumulation of EG and fragmentation of vacuoles. The expression of EGH1 in egh1Δ (revertant) reduced the accumulation of EG, and restored the morphology of vacuoles. The accumulation of EG was not detected in EGH1 and UGT51(ATG26) double-disrupted mutants (ugt51Δegh1Δ), indicating that EG was synthesized by Ugt51(Atg26) and degraded by Egh1 in vivo. These results clearly demonstrated that Egh1 is an ergosteryl-β-glucosidase that is functionally involved in the EG catabolic pathway and vacuole formation in S. cerevisiae.

  17. Defining the Roles of IFN-γ and IL-17A in Inflammation and Protection against Helicobacter pylori Infection.

    Directory of Open Access Journals (Sweden)

    Louise Sjökvist Ottsjö

    Full Text Available CD4+ T cells have been shown to be essential for vaccine-induced protection against Helicobacter pylori infection. However, the effector mechanisms leading to reductions in the gastric bacterial loads of vaccinated mice remain unclear. We have investigated the function of IFN-γ and IL-17A for vaccine-induced protection and inflammation (gastritis using IFN-γ-gene-knockout (IFN-γ-/- mice, after sublingual or intragastric immunization with H. pylori lysate antigens and cholera toxin. Bacteria were enumerated in the stomachs of mice and related to the gastritis score and cellular immune responses. We report that sublingually and intragastrically immunized IFN-γ-/- mice had significantly reduced bacterial loads similar to immunized wild-type mice compared to respective unimmunized infection controls. The reduction in bacterial loads in sublingually and intragastrically immunized IFN-γ-/- mice was associated with significantly higher levels of IL-17A in stomach extracts and lower gastritis scores compared with immunized wild-type mice. To study the role of IL-17A for vaccine-induced protection in sublingually immunized IFN-γ-/- mice, IL-17A was neutralized in vivo at the time of infection. Remarkably, the neutralization of IL-17A in sublingually immunized IFN-γ-/- mice completely abolished protection against H. pylori infection and the mild gastritis. In summary, our results suggest that IFN-γ responses in the stomach of sublingually immunized mice promote vaccine-induced gastritis, after infection with H. pylori but that IL-17A primarily functions to reduce the bacterial load.

  18. Helicobacter pylori infection: New pathogenetic and clinical aspects

    Science.gov (United States)

    Hagymási, Krisztina; Tulassay, Zsolt

    2014-01-01

    Helicobacter pylori (H. pylori) infects more than half of the world’s human population, but only 1% to 3% of infected people consequently develop gastric adenocarcinomas. The clinical outcome of the infection is determined by host genetic predisposition, bacterial virulence factors, and environmental factors. The association between H. pylori infection and chronic active gastritis, peptic ulcer disease, gastric cell carcinoma, and B cell mucosa-associated lymphoid tissue lymphoma has been well established. With the exception of unexplained iron deficiency anemia and idiopathic thrombocytopenic purpura, H. pylori infection has no proven role in extraintestinal diseases. On the other hand, there is data showing that H. pylori infection could be beneficial for some human diseases. The unpredictability of the long-term consequences of H. pylori infection and the economic challenge in eradicating it is why identification of high-risk individuals is crucial. PMID:24914360

  19. Chronic urticaria and Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Yadav Mukesh

    2008-04-01

    Full Text Available Background: Helicobacter pylori (HP have recently emerged as a novel eliciting factor for chronic urticaria (CU. The possible association between HP and CU has enormous potential, as eradicating HP could cure CU. Aims and Objectives: We conducted a study to assess the prevalence of HP infection and effect of bacterium eradication on skin lesions in patients of chronic idiopathic urticaria (CIU. Settings and Design: Four hundred sixty patients of CU attending the allergy clinic, SMS hospital, Jaipur during the period February 6, 2004, to February 6, 2006, were screened for possible eliciting factors. Patients with CIU were enrolled and others were excluded. Materials and Methods: Sixty-eight patients of CIU and similar number of age and sex matched controls, attending the allergy clinic, SMS Hospital, Jaipur were enrolled in the study. All patients underwent endoscopy with antral biopsy for urease and histopathology to identify HP-associated gastritis. Infected patients were given HP eradication therapy. Eradication of bacterium was confirmed by fecal antigen assay. Subjective response to treatment was judged using chronic urticaria quality-of-life questionnaire (CU-Q 2 oL while objective response to treatment was judged by need for ′rescue medication′ (antihistaminics. Statistical Analysis: Data were analyzed using Chi square and paired′t′ test for their level of significance. Results: HP associated gastritis was present in 48 (70.58% patients, out of which 39 (81.25% patients responded to eradication therapy. Ten (50.00% patients without HP associated gastritis showed response to symptomatic therapy. Overall 49 (72.05% patients responded and 19 (27.94% showed no response. The value of χ2 was 28.571 (P = 0.003, which showed significant association between presence of HP and response to eradication regimen. Conclusion: The response of HP eradication therapy in infected patients of CIU is significant. HP should be included in diagnostic

  20. Dyslipidemia and H pylori in gastric xanthomatosis

    Institute of Scientific and Technical Information of China (English)

    Sun Young Yi

    2007-01-01

    AIM: To investigate the relationship among gastric xanthomatosis (GX),H pylori, dyslipidemia, and gastritis in Korea, a well-known H pylori endemic area.METHODS: A total of 771 patients who had undergone gastroduodenoscopy by one endoscopist were included in this study. Among them, 54 patients with GX were assessed for H pylori infection and their endoscopic characteristics and serum lipid profiles. The findings were compared with 54 age- and sex-matched control subjects without GX.RESULTS: The prevalence of GX was 7% (54/771) with no sex difference. GX was mainly single (64.8%) and located in the antrum (53.7%). The mean diameter was 7 ± 3 mm. Mean body mass index (BMI) of patients with GX was 23.1 ± 2.8 and no one was above 30.Compared with the controls, lipid profiles of GX group showed significantly lower HDL-cholesterol (48.8 ± 12.3vs 62.9 ± 40.5, P = 0.028) and higher LDL-cholesterol (112.9 ± 29.9 vs 95.9 ± 22.4, P = 0.032). The level of total serum cholesterol, triglyceride and the existence of dyslipoproteinemia were not related to the presence of GX. However, GX showed a close relationship with endoscopically determined atrophic gastritis and histologic severity (24/53, 44.4% vs 8/54, 14.8%, P =0.0082). H pylori infection and bile reflux gastritis were not significantly related with GX.CONCLUSION: The prevalence of GX is 7% and it may be an increasing entity in Korea. Moreover, dyslipidemia and atrophic gastritis are found to be related to GX, but H pylori infection is not.

  1. Helicobacter pylori and gastroesophageal reflux disease

    Directory of Open Access Journals (Sweden)

    Nigro Casimiro

    2008-07-01

    Full Text Available Abstract Background The nature of the relationship between Helicobacter pylori and reflux oesophagitis is still not clear. To investigate the correlation between Helicobacter pylori infection and GERD taking into account endoscopic, pH-metric and histopathological data. Methods Between January 2001 and January 2003 a prospective study was performed in 146 patients with GERD in order to determine the prevalence of Helicobacter pylori infection at gastric mucosa; further the value of the De Meester score endoscopic, manometric and pH-metric parameters, i.e. reflux episodes, pathological reflux episodes and extent of oesophageal acid exposure, of the patients with and without Helicobacter pylori infection were studied and statistically compared. Finally, univariate analysis of the above mentioned data were performed in order to evaluate the statistical correlation with reflux esophagitis. Results There were no statistically significant differences between the two groups, HP infected and HP negative patients, regarding age, gender and type of symptoms. There was no statistical difference between the two groups regarding severity of symptoms and manometric parameters. The value of the De Meester score and the ph-metric parameters were similar in both groups. On univariate analysis, we observed that hiatal hernia (p = 0,01, LES size (p = 0,05, oesophageal wave length (p = 0,01 and pathological reflux number (p = 0,05 were significantly related to the presence of reflux oesophagitis. Conclusion Based on these findings, it seems that there is no significant evidence for an important role for H. pylori infection in the development of GERD and erosive esophagitis. Nevertheless, current data do not provide sufficient evidence to define the relationship between HP and GERD. Further assessments in prospective large studies are warranted.

  2. Challenges in Diagnosis of H. Pylori Infection in Children

    OpenAIRE

    M Sobhani Shahmirzadi

    2014-01-01

    H. pylori infection is usually acquired in early childhood. Its role in gastrointestinal and extra intestinal complaints and serious consequences in adulthood make it as challenging issues. Despite different clinical presentations, in most children, the presence of H. pylori infection does not lead to clinically apparent disease, even when it causes chronic active gastritis. Some of most important recommendations for managing H. pylori infection in children based on Guidelines from ESPGHAN an...

  3. Helicobacter pylori infection: New pathogenetic and clinical aspects

    OpenAIRE

    Hagymási, Krisztina; Tulassay, Zsolt

    2014-01-01

    Helicobacter pylori (H. pylori) infects more than half of the world’s human population, but only 1% to 3% of infected people consequently develop gastric adenocarcinomas. The clinical outcome of the infection is determined by host genetic predisposition, bacterial virulence factors, and environmental factors. The association between H. pylori infection and chronic active gastritis, peptic ulcer disease, gastric cell carcinoma, and B cell mucosa-associated lymphoid tissue lymphoma has been wel...

  4. "Targeted disruption of the epithelial-barrier by Helicobacter pylori"

    OpenAIRE

    Wroblewski Lydia E; Peek Richard M

    2011-01-01

    Abstract Helicobacter pylori colonizes the human gastric epithelium and induces chronic gastritis, which can lead to gastric cancer. Through cell-cell contacts the gastric epithelium forms a barrier to protect underlying tissue from pathogenic bacteria; however, H. pylori have evolved numerous strategies to perturb the integrity of the gastric barrier. In this review, we summarize recent research into the mechanisms through which H. pylori disrupts intercellular junctions and disrupts the gas...

  5. Management and response to treatment of Helicobacter pylori gastritis.

    OpenAIRE

    Mahony, M J; Wyatt, J I; Littlewood, J M

    1992-01-01

    Gastritis associated with Helicobacter pylori was present in gastric biopsies from 24/95 (25%) children and adolescents undergoing endoscopy for recurrent abdominal pain and upper gastrointestinal symptoms. H pylori associated gastritis occurred mainly in older children (8-16 years) and was significantly associated with low socioeconomic class and a family history of peptic ulcer disease. Antral nodularity was a common endoscopic finding in H pylori positive children. Eighteen children, all o...

  6. Lymphoid follicles in children with Helicobacter pylori-negative gastritis

    Science.gov (United States)

    Broide, Efrat; Richter, Vered; Mendlovic, Sonia; Shalem, Tzippora; Eindor-Abarbanel, Adi; Moss, Steven F; Shirin, Haim

    2017-01-01

    Purpose The prevalence of Helicobacter pylori gastritis has been declining, whereas H. pylori-negative gastritis has become more common. We evaluated chronic gastritis in children with regard to H. pylori status and celiac disease (CD). Patients and methods Demographic, clinical, endoscopic, and histologic features of children who underwent elective esophagogastroduodenoscopy were reviewed retrospectively. Gastric biopsies from the antrum and corpus of the stomach were graded using the Updated Sydney System. H. pylori presence was defined by hematoxylin and eosin, Giemsa, or immunohistochemical staining and urease testing. Results A total of 184 children (61.9% female) met the study criteria with a mean age of 10 years. A total of 122 (66.3%) patients had chronic gastritis; 74 (60.7%) were H. pylori-negative. Children with H. pylori-negative gastritis were younger (p=0.003), were less likely to present with abdominal pain (p=0.02), and were mostly of non-Arabic origin (p=0.011). Nodular gastritis was found to be less prevalent in H. pylori-negative gastritis (6.8%) compared with H. pylori-positive gastritis (35.4%, pgastritis and lymphoid follicles were associated most commonly with H. pylori. Although less typical, lymphoid follicles were demonstrated in 51.3% of H. pylori-negative patients. The presence or absence of CD was not associated with histologic findings in H. pylori-negative gastritis. Conclusion Our findings suggest that lymphoid follicles are a feature of H. pylori-negative gastritis in children independent of their CD status. PMID:28860835

  7. "Targeted disruption of the epithelial-barrier by Helicobacter pylori"

    Directory of Open Access Journals (Sweden)

    Wroblewski Lydia E

    2011-11-01

    Full Text Available Abstract Helicobacter pylori colonizes the human gastric epithelium and induces chronic gastritis, which can lead to gastric cancer. Through cell-cell contacts the gastric epithelium forms a barrier to protect underlying tissue from pathogenic bacteria; however, H. pylori have evolved numerous strategies to perturb the integrity of the gastric barrier. In this review, we summarize recent research into the mechanisms through which H. pylori disrupts intercellular junctions and disrupts the gastric epithelial barrier.

  8. Helicobacter pylori Infection in Ontario: Prevalence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Farah Naja

    2007-01-01

    Full Text Available BACKGROUND: Helicobacter pylori has been classified by the World Health Organization as a type I carcinogen. Nearly 50% of the world’s population is estimated to be infected with H pylori. Prevalence patterns of the infection are different between developing and developed countries. The present study had two objectives – to estimate the prevalence of H pylori infection in Ontario, and to evaluate the relationship between the infection and various demographic characteristics and selected lifestyle factors.

  9. Cloning and Expression of Helicobacter pylori HpaA Gene

    OpenAIRE

    Moein Farshchian; Saman Hoseinkhani; Javad Atoofi; Shahin Najar Peerayeh

    2009-01-01

    Objective: Helicobacter pylori is associated with chronic gastritis, peptic ulcers, gastric adenocarcinomaand gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Antibiotictherapies do not protect from potential re-infection and have a risk for development of drugresistance. Therefore, prophylactic vaccine mediated protection against H. pylori is an attractiveclinical interest. H. pylori adhesin A (HpaA) is a conserved surface lipoprotein and playsimportant roles in the pathogenesis of...

  10. Precise role of H pylori in duodenal ulceration

    Institute of Scientific and Technical Information of China (English)

    Michael Hobsley; Frank I Tovey; John Holton

    2006-01-01

    The facts that H pylori infection is commoner in duodenal ulcer (DU) patients than in the normal population, and that eradication results in most cases being cured,have led to the belief that it causes DU. However, early cases of DU are less likely than established ones to be infected. H pylori-negative cases are usually ascribed to specific associated factors such as non-steroidal anti-inflammatory drugs (NSAIDs), Crohn's disease,and hypergastrinaemia, but even after excluding these, several H pylori-negative cases remain and are particularly common in areas of low prevalence of H pylori infection. Moreover, this incidence of H pylori negative DU is not associated with a fall in overall DU prevalence when compared with countries with a higher H pylori prevalence. In countries with a high H pylori prevalence there are regional differences in DU prevalence, but no evidence of an overall higher prevalence of DU than in countries with a low H pylori prevalence. There is no evidence that virulence factors are predictive of clinical outcome. After healing following eradication of H pylori infection DU can still recur.Medical or surgical measures to reduce acid output can lead to long-term healing despite persistence of H pylori infection. Up to half of cases of acute DU perforation are H pylori negative. These findings lead to the conclusion that H pylori infection does not itself cause DU, but leads to resistance to healing, i.e., chronicity. This conclusion is shown not to be incompatible with the universally high prevalence of DU compared with controls.

  11. [On the rating of Helicobacter pylori in drinking water].

    Science.gov (United States)

    Fedichkina, T P; Solenova, L G; Zykova, I E

    2014-01-01

    There are considered the issues related to the possibility to rate of Helicobacter pylori (H. pylori) content in drinking water. There is described the mechanism of of biofilm formation. The description refers to the biofilm formation mechanism in water supply systems and the existence of H. pylori in those systems. The objective premises of the definition of H. pylori as a potential limiting factor for assessing the quality of drinking water have been validated as follows: H. pylori is an etiologic factor associated to the development of chronic antral gastritis, gastric ulcer and duodenal ulcer, and gastric cancer either, in the Russian population the rate of infection with H. pylori falls within range of 56 - 90%, water supply pathway now can be considered as a source of infection of the population with H. pylori, the existence of WHO regulatory documents considering H. pylori as a candidate for standardization of the quality of the drinking water quite common occurrence of biocorrosion, the reduction of sanitary water network reliability, that creates the possibility of concentrating H. pylori in some areas of the water system and its delivery to the consumer of drinking water, and causes the necessity of the prevention of H. pylori-associated gastric pathology of the population. A comprehensive and harmonized approach to H. pylori is required to consider it as a candidate to its rating in drinking water. Bearing in mind the large economic losses due to, on the one hand, the prevalence of disease caused by H. pylori, and, on the other hand, the biocorrosion of water supply system, the problem is both relevant in terms of communal hygiene and economy.

  12. The Pathogen-Occupied Vacuoles of Anaplasma phagocytophilum and Anaplasma marginale Interact with the Endoplasmic Reticulum.

    Science.gov (United States)

    Truchan, Hilary K; Cockburn, Chelsea L; Hebert, Kathryn S; Magunda, Forgivemore; Noh, Susan M; Carlyon, Jason A

    2016-01-01

    The genus Anaplasma consists of tick-transmitted obligate intracellular bacteria that invade white or red blood cells to cause debilitating and potentially fatal infections. A. phagocytophilum, a human and veterinary pathogen, infects neutrophils to cause granulocytic anaplasmosis. A. marginale invades bovine erythrocytes. Evidence suggests that both species may also infect endothelial cells in vivo. In mammalian and arthropod host cells, A. phagocytophilum and A. marginale reside in host cell derived pathogen-occupied vacuoles (POVs). While it was recently demonstrated that the A. phagocytophilum-occupied vacuole (ApV) intercepts membrane traffic from the trans-Golgi network, it is unclear if it or the A. marginale-occupied vacuole (AmV) interacts with other secretory organelles. Here, we demonstrate that the ApV and AmV extensively interact with the host endoplasmic reticulum (ER) in endothelial, myeloid, and/or tick cells. ER lumen markers, calreticulin, and protein disulfide isomerase, and the ER membrane marker, derlin-1, were pronouncedly recruited to the peripheries of both POVs. ApV association with the ER initiated early and continued throughout the infection cycle. Both the ApV and AmV interacted with the rough ER and smooth ER. However, only derlin-1-positive rough ER derived vesicles were delivered into the ApV lumen where they localized with intravacuolar bacteria. Transmission electron microscopy identified multiple ER-POV membrane contact sites on the cytosolic faces of both species' vacuoles that corresponded to areas on the vacuoles' lumenal faces where intravacuolar Anaplasma organisms closely associated. A. phagocytophilum is known to hijack Rab10, a GTPase that regulates ER dynamics and morphology. Yet, ApV-ER interactions were unhindered in cells in which Rab10 had been knocked down, demonstrating that the GTPase is dispensable for the bacterium to parasitize the ER. These data establish the ApV and AmV as pathogen-host interfaces that directly

  13. Helicobacter pylori damages human gallbladder epithelial cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Dong-Feng Chen; Lu Hu; Ping Yi; Wei-Wen Liu; Dian-Chun Fang; Hong Cao

    2008-01-01

    AIM: To study the mechanism by which Helicobacter pylori (Hpy/orO damages human gallbladder epithelial cells (HGBEC).METHODS: H pylori isolated from gallbladder were cultured in a liquid medium. Different concentration supernatants and sonicated extracts of H pylori cells were then added to HGBEC in a primary culture. The morphological changes in HGBEC as well as changes in the levels of alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and glutamyltransferase (GGT)were measured.RESULTS: According to the culture curve of HGBEC,it was convenient to study the changes in HGBEC by adding H pylori sonicated extracts and H pylori culture supernatants. Both H pylori sonicated extracts and H pylori culture supernatants had a significant influence on HGBEC morphology, i.e. HGBEC grew more slowly, their viability decreased and their detachment increased. Furthermore, HGBEC ruptured and died. The levels of ALP (33.84 ± 6.00 vs 27.01± 4.67, P < 0.05), LDH (168.37 ± 20.84 vs 55.51 ±17.17, P < 0.01) and GGT (42.01 ± 6.18 vs 25.34 ±4.33, P < 0.01) significantly increased in the HGBEC culture supernatant in a time- and concentrationdependent. The damage to HGBEC in Hpylori culture liquid was more significant than that in H pylori sonicated extracts.CONCLUSION: H pylori induces no obvious damage to HGBEC.

  14. Celecoxib inhibits Helicobacter pylori colonization-related factors

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate the effect of celecoxib,a selective COX-2 inhibitor,on Helicobacter pylori(H.pylori) colonization-related factors and its mechanism.METHODS:After co-incubation with celecoxib,morphology of H.pylori strain 26695 was observed under a transmission electron microscope.Flagella motility was assessed by stab agar motility test.Adherence of H.pylori to AGS cells was determined by enzyme linked immunosorbent assay.Levels of mRNA expression in flagellar genes(flaA,flaB),urease genes(ureA,ureB)and ...

  15. Chronic Gastritis and its Association with H. Pylori Infection.

    Science.gov (United States)

    Fatema, J; Khan, A H; Uddin, M J; Rahman, M H; Saha, M; Safwath, S A; Alam, M J; Mamun, M A

    2015-10-01

    This cross sectional study was designed to see association of chronic gastritis including its type with H. pylori infection. Consecutive patients undergoing endoscopic examination having histopathological evidence of chronic gastritis were enrolled in the study and was done in Sylhet MAG Osmani Medical College from July 2011 to June 2012. Biopsies were taken from antrum, body and fundus in all patients. Histopathological examinations were done using H-E stain and for detection of H. pylori, rapid urease test, anti-H.pylori antibody test and histopathological test with modified Giemsa stain were done. Patients having results positive in at least two methods were considered infected by H. pylori. Total 80 dyspeptic patients having chronic gastritis were evaluated. Out of them 67(83.8%) had H. pylori infection and 13(16.2%) were H. pylori negative. Among all patients 57(71.2%) had pangastritis and 23(28.8%) had antral gastritis with female and male predominance respectively. H. pylori infection was present in 49(86.0%) cases of pangastritis and 18(78.3%) cases of antral gastritis. H. pylori infection was a little higher among males (34, 50.7%) females (33, 49.3%). H. pylori infection is the predominant cause of chronic gastritis and pangastritis is the major type.

  16. Age-dependent eradication of Helicobacter pylori in Japanese patients

    Science.gov (United States)

    Mamori, Satoshi; Higashida, Akihiro; Kawara, Fumiaki; Ohnishi, Katsuhiro; Takeda, Akihiko; Senda, Eri; Ashida, Cho; Yamada, Hajime

    2010-01-01

    AIM: To determine the general risk factors affecting the failure rate of first-line eradication therapy in Japanese patients with Helicobacter pylori (H. pylori) infection. METHODS: The present study enrolled 253 patients who had an H. pylori infection, underwent gastro-endoscopy, and were treated with H. pylori eradication therapy. Eradication therapy consisted of 30 mg lansoprazole plus 750 mg amoxicillin and 400 mg clarithromycin twice daily for 7 d. All of the patients underwent a 13C urea breath test at least 1 mo after the completion of eradication therapy. The current study investigated the independent factors associated with successful H. pylori eradication using a multiple logistic regression analysis. RESULTS: The overall success rate in the patients was 85.8%. Among the general factors examined in the multivariate analyses, only having an age less than 50 years was found to be significantly associated with a poor response to H. pylori eradication. Moreover, side effects were the only clinical factors in the patients who were under 50 years of age that significantly influenced the poor response to H. pylori eradication. CONCLUSION: H. pylori-positive elderly patients should undergo eradication therapy. In addition, it is necessary to improve H. pylori eradication therapy in younger patients. PMID:20806435

  17. Association between thyroid autoimmunity and Helicobacter pylori infection

    Science.gov (United States)

    Choi, Yun Mi; Kim, Tae Yong; Kim, Eui Young; Jang, Eun Kyung; Jeon, Min Ji; Kim, Won Gu; Shong, Young Kee; Kim, Won Bae

    2017-01-01

    Background/Aims There have been controversial reports linking Helicobacter pylori infection to autoimmune thyroid disease (AITD). However, data regarding the relationship are limited for Asian populations, which have an extremely high prevalence of H. pylori infection. We performed this study to investigate the association between H. pylori infection and AITD in Koreans. Methods This study involved adults aged 30 to 70 years who had visited a health promotion center. A total of 5,502 subjects were analysed. Thyroid status was assessed by free thyroxine, thyroid stimulating hormone, and anti-thyroid peroxidase antibody (TPO-Ab). Immunoglobulin G (IgG) antibodies to H. pylori were measured as an indication of H. pylori infection. We compared the prevalence of TPO-Ab in subjects with and without H. pylori infection. Results H. pylori IgG antibodies were found in 2,875 subjects (52.3%), and TPO-Ab were found in 430 (7.8%). Individuals positive for H. pylori Ab were older than those negative for H. pylori Ab (p thyroiditis. PMID:28092700

  18. Helicobacter pylori vs coronary heart disease- searching for connections

    Institute of Scientific and Technical Information of China (English)

    Magdalena; Chmiela; Adrian; Gajewski; Karolina; Rudnicka

    2015-01-01

    In this review,we discussed the findings and concepts underlying the potential role of Helicobacter pylori(H.pylori) infections in the initiation,development or persistence of atherosclerosis and coronary heart disease(CHD).This Gram-negative bacterium was described by Marshall and Warren in 1984.The majority of infected subjects carries and transmits H.pylori with no symptoms; however,in some individuals these bacteria may cause peptic ulcers,and even gastric cancers.The widespread prevalence of H.pylori infections and the fact that frequently they remain asymptomatic may suggest that,similarly to intestinal microflora,H.pylori may deliver antigens that stimulate not only local,but also systemic inflammatory response.Recently,possible association between H.pylori infection and extragastric disorders has been suggested.Knowledge on the etiology of atherosclerosis together with current findings in the area of H.pylori infections constitute the background for the newly proposed hypothesis that those two processes may be related.Many research studies confirm the indirect association between the prevalence of H.pylori and the occurrence of CHD.According to majority of findings the involvement of H.pylori in this process is based on the chronic inflammation which might facilitate the CHDrelated pathologies.It needs to be elucidated,if the infection initiates or just accelerates the formation of atheromatous plaque.

  19. Nobeli auhinna tõi Helicobacter pylori / Juhan Kaldre

    Index Scriptorium Estoniae

    Kaldre, Juhan

    2005-01-01

    Nobeli meditsiiniauhind määrati sel aastal Austraalia teadlastele Robin Warrenile ja Barry Marshallile, kes avastasid, et gastriit ning peptiline haavand tekib Helicobacter pylori infektsiooni tulemusena

  20. Nobeli auhinna tõi Helicobacter pylori / Juhan Kaldre

    Index Scriptorium Estoniae

    Kaldre, Juhan

    2005-01-01

    Nobeli meditsiiniauhind määrati sel aastal Austraalia teadlastele Robin Warrenile ja Barry Marshallile, kes avastasid, et gastriit ning peptiline haavand tekib Helicobacter pylori infektsiooni tulemusena

  1. Age-dependent eradication of Helicobacter pylori in Japanese patients

    Institute of Scientific and Technical Information of China (English)

    Satoshi; Mamori; Akihiro; Higashida; Fumiaki; Kawara; Katsuhiro; Ohnishi; Akihiko; Takeda; Eri; Senda; Cho; Ashida; Hajime; Yamada

    2010-01-01

    AIM:To determine the general risk factors affecting the failure rate of first-line eradication therapy in Japanese patients with Helicobacter pylori(H.pylori)infection.METHODS:The present study enrolled 253 patients who had an H.pylori infection,underwent gastroendoscopy,and were treated with H.pylori eradication therapy.Eradication therapy consisted of 30 mg lansoprazole plus 750 mg amoxicillin and 400 mg clarithromycin twice daily for 7 d.All of the patients underwent a 13 C urea breath test at least 1 mo...

  2. Food toxin detection with atomic force microscope

    Science.gov (United States)

    Externally introduced toxins or internal spoilage correlated pathogens and their metabolites are all potential sources of food toxins. To prevent and protect unsafe food, many food toxin detection techniques have been developed to detect various toxins for quality control. Although several routine m...

  3. Shiga Toxin Producing Escherichia coli.

    Science.gov (United States)

    Bryan, Allen; Youngster, Ilan; McAdam, Alexander J

    2015-06-01

    Shiga toxin-producing Escherichia coli (STEC) is among the common causes of foodborne gastroenteritis. STEC is defined by the production of specific toxins, but within this pathotype there is a diverse group of organisms. This diversity has important consequences for understanding the pathogenesis of the organism, as well as for selecting the optimum strategy for diagnostic testing in the clinical laboratory. This review includes discussions of the mechanisms of pathogenesis, the range of manifestations of infection, and the several different methods of laboratory detection of Shiga toxin-producing E coli.

  4. Helicobacter pylori may induce bile reflux: link between H pylori and bile induced injury to gastric epithelium.

    Science.gov (United States)

    Ladas, S D; Katsogridakis, J; Malamou, H; Giannopoulou, H; Kesse-Elia, M; Raptis, S A

    1996-01-01

    Helicobacter pylori and duodenogastric reflux are both recognised as playing aetiological roles in chronic gastritis. This study investigated whether H pylori colonisation of the antral mucosa and duodenogastric reflux are independent phenomena or have a causal relationship. Thirty eight patients (15 men, 23 women) aged (mean (SD)) 48 (17) years participated. Each patient underwent gastroscopy. Antral biopsy specimens were taken to investigate H pylori colonisation. In addition BrIDA-99mTc/111In-DTPA scintigraphy was used to quantify duodenogastric reflux. H pylori positive patients who were found to have duodenogastric reflux were treated with amoxycillin (1 g/d) and metronidazole (1.5 g/d) for seven days and four tablets of bismuth subcitrate daily for four weeks. Follow up antral biopsies and scintigraphy were repeated at six months. Duodenogastric reflux could not be found in 18 patients, including eight (44%) who were H pylori positive. Ten of the 11 patients who had duodenogastric reflux (reflux % 11.6 (9.2)), however, were H pylori positive (chi 2 = 6.26, p = 0.01). These 10 patients were given eradication treatment. At six months, in six patients who became H pylori negative, duodenogastric reflux was significantly reduced from a pretreatment value of 14.3% to 3.3% (two tail, paired t = 2.57, p = 0.016). These data suggest that H pylori may induced duodenogastric reflux which may be important in the pathogenesis of H pylori gastritis or carcinogenesis, or both. PMID:8566844

  5. A functional connection of Dictyostelium paracaspase with the contractile vacuole and a possible partner of the vacuolar proton ATPase

    Indian Academy of Sciences (India)

    Entsar Saheb; Ithay Biton; Katherine Maringer; John Bush

    2013-09-01

    Dictyostelium discoideum possesses only one caspase family member, paracaspase (pcp). Two separate mutant cell lines were first analysed: one cell line was an over-expressed GFP-tagged Pcp (GFP-Pcp), while the other cell line was a pcp-null (pcp-). Microscopic analysis of cells expressing GFP-Pcp revealed that Pcp was associated with the contractile vacuole membrane consisting of bladder-like vacuoles. This association was disrupted when cells were exposed to osmotic stress conditions. Compared with wild-type cells, the GFP-Pcp-over-expressing cells were susceptible to osmotic stress and were seen to be very rounded in hypo-osmotic conditions and contained more abnormally swollen contractile vacuole. Cells with pcp- were also rounded but had few, if any, contractile vacuoles. These observations suggest that Pcp is essential for Dictyostelium osmotic regulation via its functioning in the contractile vacuole system. Subjecting these cells to selected contractile vacuole inhibitor provided additional support for these findings. Furthermore, yeast two-hybrid system identified vacuolar proton ATPase (VatM) as the protein interacting with Pcp. Taken together, this work gives evidence for an eukaryotic paracaspase to be associated with both localization in and regulation of the contractile vacuolar system, an organelle critical for maintaining the normal morphology of the cell.

  6. Epsilon toxin: a fascinating pore-forming toxin.

    Science.gov (United States)

    Popoff, Michel R

    2011-12-01

    Epsilon toxin (ETX) is produced by strains of Clostridium perfringens classified as type B or type D. ETX belongs to the heptameric β-pore-forming toxins including aerolysin and Clostridium septicum alpha toxin, which are characterized by the formation of a pore through the plasma membrane of eukaryotic cells consisting in a β-barrel of 14 amphipatic β strands. By contrast to aerolysin and C. septicum alpha toxin, ETX is a much more potent toxin and is responsible for enterotoxemia in animals, mainly sheep. ETX induces perivascular edema in various tissues and accumulates in particular in the kidneys and brain, where it causes edema and necrotic lesions. ETX is able to pass through the blood-brain barrier and stimulate the release of glutamate, which accounts for the symptoms of nervous excitation observed in animal enterotoxemia. At the cellular level, ETX causes rapid swelling followed by cell death involving necrosis. The precise mode of action of ETX remains to be determined. ETX is a powerful toxin, however, it also represents a unique tool with which to vehicle drugs into the central nervous system or target glutamatergic neurons.

  7. Helicobacter pylori-induced modulation of the promoter methylation of Wnt antagonist genes in gastric carcinogenesis.

    Science.gov (United States)

    Yang, Hyo-Joon; Kim, Sang Gyun; Lim, Joo Hyun; Choi, Ji Min; Kim, Woo Ho; Jung, Hyun Chae

    2017-06-22

    This study aimed to investigate the changes in the promoter methylation and gene expression of multiple Wnt antagonists between the chronic infection and eradication of Helicobacter pylori (H. pylori) in gastric carcinogenesis. The levels of methylation and corresponding mRNA expression of seven Wnt antagonist genes (SFRP1, -2, -5, DKK1, -2, -3, WIF1) were compared among the patients with H. pylori-positive gastric cancers (GCs), and H. pylori-positive and H. pylori-negative controls, by quantitative MethyLight assay and real-time reverse transcription (RT)-polymerase chain reaction (PCR), respectively. The changes of the methylation and expression levels of the genes were also compared between the H. pylori eradication and H. pylori-persistent groups 1 year after endoscopic resection of GCs. The methylation levels of SFRP and DKK family genes were significantly increased in the patients with H. pylori-positive GCs and followed by H. pylori-positive controls compared with H. pylori-negative controls (P pylori-negative controls, H. pylori-positive controls, and to H. pylori-positive GCs (P pylori eradication (P pylori-associated gastric carcinogenesis. The epigenetic field may not be reversed even after H. pylori eradication except by DKK3 methylation.

  8. Endosome–mitochondria juxtaposition during apoptosis induced by H. pylori VacA

    Science.gov (United States)

    Calore, F; Genisset, C; Casellato, A; Rossato, M; Codolo, G; Esposti, MD; Scorrano, L; de Bernard, M

    2011-01-01

    The vacuolating cytotoxin (VacA) is an important virulence factor of Helicobacter pylori with pleiotropic effects on mammalian cells, including the ability to trigger mitochondria-dependent apoptosis. However, the mechanism by which VacA exerts its apoptotic function is unclear. Using a genetic approach, in this study we show that killing by VacA requires the proapoptotic Bcl-2 family members BAX and BAK at the mitochondrial level, but not adequate endoplasmic reticulum Ca2+ levels, similarly controlled by BAX and BAK. A combination of subcellular fractionation and imaging shows that wild-type VacA, but not mutants in its channel-forming region, induces the accumulation of BAX on endosomes and endosome–mitochondria juxtaposition that precedes the retrieval of active BAX on mitochondria. It is noteworthy that in Bax- and Bak-deficient cells, VacA is unable to cause endosome–mitochondria juxtaposition and is not retrieved in mitochondria. Thus, VacA causes BAX/BAK-dependent juxtaposition of endosomes and mitochondria early in the process of cell death, revealing a new function for these proapoptotic proteins in the regulation of relative position of organelles. PMID:20431599

  9. Host pathogen interactions in Helicobacter pylori related gastric cancer

    Science.gov (United States)

    Chmiela, Magdalena; Karwowska, Zuzanna; Gonciarz, Weronika; Allushi, Bujana; Stączek, Paweł

    2017-01-01

    Helicobacter pylori (H. pylori), discovered in 1982, is a microaerophilic, spiral-shaped gram-negative bacterium that is able to colonize the human stomach. Nearly half of the world's population is infected by this pathogen. Its ability to induce gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma has been confirmed. The susceptibility of an individual to these clinical outcomes is multifactorial and depends on H. pylori virulence, environmental factors, the genetic susceptibility of the host and the reactivity of the host immune system. Despite the host immune response, H. pylori infection can be difficult to eradicate. H. pylori is categorized as a group I carcinogen since this bacterium is responsible for the highest rate of cancer-related deaths worldwide. Early detection of cancer can be lifesaving. The 5-year survival rate for gastric cancer patients diagnosed in the early stages is nearly 90%. Gastric cancer is asymptomatic in the early stages but always progresses over time and begins to cause symptoms when untreated. In 97% of stomach cancer cases, cancer cells metastasize to other organs. H. pylori infection is responsible for nearly 60% of the intestinal-type gastric cancer cases but also influences the development of diffuse gastric cancer. The host genetic susceptibility depends on polymorphisms of genes involved in H. pylori-related inflammation and the cytokine response of gastric epithelial and immune cells. H. pylori strains differ in their ability to induce a deleterious inflammatory response. H. pylori-driven cytokines accelerate the inflammatory response and promote malignancy. Chronic H. pylori infection induces genetic instability in gastric epithelial cells and affects the DNA damage repair systems. Therefore, H. pylori infection should always be considered a pro-cancerous factor. PMID:28321154

  10. Helicobacter pylori-Negative Gastritis: Prevalence and Risk Factors

    Science.gov (United States)

    Nordenstedt, Helena; Graham, David Y.; Kramer, Jennifer R.; Rugge, Massimo; Verstovsek, Gordana; Fitzgerald, Stephanie; Alsarraj, Abeer; Shaib, Yasser; Velez, Maria E.; Abraham, Neena; Anand, Bhupinderjit; Cole, Rhonda; El-Serag, Hashem B.

    2014-01-01

    OBJECTIVES Recent studies using histology alone in select patients have suggested that Helicobacter pylori-negative gastritis may be common. The objective of this study was to investigate the prevalence of H. pylori among individuals with histologic gastritis. METHODS Subjects between 40 and 80 years underwent elective esophagogastroduodenoscopy at a VA Medical Center. Gastric biopsies were mapped from seven prespecified sites (two antrum, four corpus, and one cardia) and graded by two gastrointestinal pathologists, using the Updated Sydney System. H. pylori-negative required four criteria: negative triple staining at all seven gastric sites, negative H. pylori culture, negative IgG H. pylori serology, and no previous treatment for H. pylori. Data regarding tobacco smoking, alcohol drinking, nonsteroidal anti-inflammatory drug, and proton pump inhibitor (PPI) use were obtained by questionnaire. RESULTS Of the 491 individuals enrolled, 40.7% (200) had gastritis of at least grade 2 in at least one biopsy site or grade 1 in at least two sites. Forty-one (20.5%) had H. pylori-negative gastritis; most (30 or 73.2%) had chronic gastritis, five (12.2%) had active gastritis, and six (14.6%) had both. H. pylori-negative gastritis was approximately equally distributed in the antrum, corpus, and both antrum and corpus. Past and current PPI use was more frequent in H. pylori-negative vs. H. pylori-positive gastritis (68.2% and 53.8%; P = 0.06). CONCLUSIONS We used multiple methods to define non-H. pylori gastritis and found it in 21% of patients with histologic gastritis. While PPI use is a potential risk factor, the cause or implications of this entity are not known. PMID:23147524

  11. Helicobacter pylori and non-malignant upper gastrointestinal diseases.

    Science.gov (United States)

    Vasapolli, Riccardo; Malfertheiner, Peter; Kandulski, Arne

    2016-09-01

    Peptic ulcer disease (PUD) has been further decreased over the last decades along with decreasing prevalence of Helicobacter pylori-associated PUD. A delayed H. pylori eradication has been associated with an increased risk of rehospitalization for complicated recurrent peptic ulcer and reemphasized the importance of eradication especially in patients with peptic ulcer bleeding (PUB). PUB associated with NSAID/aspirin intake and H. pylori revealed an additive interaction in gastric pathophysiology which favors the "test-and-treat" strategy for H. pylori in patients with specific risk factors. The H. pylori-negative and NSAID-negative "idiopathic PUD" have been increasingly observed and associated with slower healing tendency, higher risk of recurrence, and greater mortality. Helicobacter pylori-associated dyspepsia has been further investigated and finally defined by the Kyoto consensus. Helicobacter pylori eradication therapy is advised as first option in this group of patients. Only in the case of symptom persistence or recurrence after eradication therapy, dyspeptic patients should be classified as functional dyspepsia (FD). There were few new data in 2015 on the role of H. pylori infection in gastroesophageal reflux disease (GERD), and in particular Barrett's esophagus. A lower prevalence of gastric atrophy with less acid output in patients with erosive esophagitis confirmed previous findings. In patients with erosive esophagitis, no difference was observed in healing rates neither between H. pylori-positive and H. pylori-negative patients nor between patients that underwent eradication therapy compared to patients without eradication. These findings are in line with the current consensus guidelines concluding that H. pylori eradication has no effects on symptoms and does not aggravate preexisting GERD. © 2016 John Wiley & Sons Ltd.

  12. Prevalence of Helicobacter pylori in benign gastric ulcers in a cohort of Sri Lankan patients.

    Science.gov (United States)

    Wijetunge, S; Kotakadeniya, R; Noordeen, F; Buharideen, S M; Samarasinghe, B; Dharmapala, A; Galketiya, K B

    2015-12-01

    Helicobacter pylori prevalence is decreasing globally and prevalence of non H. pylori gastric ulcers is increasing. The following study was conducted to assess the prevalence of H. pylori in benign gastric ulcers in a sample of Sri Lankan patients. This was a cross-sectional study of 59 dyspeptic patients with benign gastric ulcers. Multiple endoscopic gastric biopsies were obtained and histology, immunohistochemistry and polymerase chain reaction were performed for H. pylori detection. An immunochromatography assay was performed to detect blood anti H. pylori antibodies. Four (6.8%) were positive for H. pylori. Therefore, it is likely that most benign gastric ulcers are of non-H. pylori aetiology.

  13. Bacterial Toxins for Cancer Therapy

    OpenAIRE

    Zahaf, Nour-Imene; Schmidt, Gudula

    2017-01-01

    Several pathogenic bacteria secrete toxins to inhibit the immune system of the infected organism. Frequently, they catalyze a covalent modification of specific proteins. Thereby, they block production and/or secretion of antibodies or cytokines. Moreover, they disable migration of macrophages and disturb the barrier function of epithelia. In most cases, these toxins are extremely effective enzymes with high specificity towards their cellular substrates, which are often central signaling molec...

  14. A fluid model for Helicobacter pylori

    Science.gov (United States)

    Reigh, Shang-Yik; Lauga, Eric

    2015-11-01

    Swimming microorganisms and self-propelled nanomotors are often found in confined environments. The bacterium Helicobacter pylori survives in the acidic environment of the human stomach and is able to penetrate gel-like mucus layers and cause infections by locally changing the rheological properties of the mucus from gel-like to solution-like. In this talk we propose an analytical model for the locomotion of Helicobacter pylori as a confined spherical squirmer which generates its own confinement. We solve analytically the flow field around the swimmer, and derive the swimming speed and energetics. The role of the boundary condition in the outer wall is discussed. An extension of our model is also proposed for other biological and chemical swimmers. Newton Trust.

  15. Helicobacter pylori and gastric or duodenal ulcer.

    Science.gov (United States)

    2016-01-01

    In patients with gastric or duodenal ulcer associated with Helicobacter pylori, treatment of the infection improves healing and prevents complications and recurrences. The drug regimen generally consists of a high-dose proton-pump inhibitor (PPI) such as omeprazole plus antibiotics. Using the standard Prescrire methodology, we conducted a review of the literature in order to determine the standard empirical antibiotic regimen for H. pylori infection in adults with gastric or duodenal ulcer in France. In 2015, due to an increase in H. pylori resistance to clarithromycin, a 7-day course of the PPI + clarithromycin + amoxicillin combination is effective in only about 70% of cases. A Cochrane systematic review and meta-analysis of trials involving thousands of patients suggests that prolonging treatment with a PPI + amoxicillin + clarithromycin or a PPI + amoxicillin + metronidazole to 10 or 14 days improves the rate of H. pylori eradication by 5% to 10%. A metanalysis of seven trials including a total of about 1000 patients showed that combination therapy with a PPI + amoxicillin + clarithromycin + metronidazole for 5 days eradicates H. pylori in about 90% of cases, compared to about 80% of cases with a PPI + amoxicillin + clarithromycin given for 7 days. Sequential treatment with amoxicillin for 5 days, followed by clarithromycin + metronidazole for 5 days, has also been tested in thousands of patients. Efficacy and adverse effects were similar to those observed when the same antibiotics were taken simultaneously for 5 days. In randomised trials, replacing clarithromycin or amoxicillin with a fluoroquinolone yielded conflicting results. In 2009, nearly 20% of H. pylori isolates were resistant to levofloxacin in France. Tetracycline has only been evaluated in combination with bismuth. The few available data on doxycycline suggest that its efficacy is similar to that of tetracycline. A fixed-dose combination of bismuth subcitrate potassium + metronidazole

  16. Changes in vacuolation in the root apex cells of soybean seedlings in microgravity

    Science.gov (United States)

    Klymchuk, D. O.; Kordyum, E. L.; Vorobyova, T. V.; Chapman, D. K.; Brown, C. S.

    2003-05-01

    Changes in the vacuolation in root apex cells of soybean ( Glycine max L. [Merr.]) seedlings grown in microgravity were investigated. Spaceflight and ground control seedlings were grown in the absence or presence of KMnO 4 (to remove ethylene) for 6 days. After landing, in order to study of cell ultrastructure and subcellular free calcium ion distribution, seedling root apices were fixed in 2.5% (w/v) glutaraldehyde in 0.1 M cacodylate buffer and 2% (w/v) glutaraldehyde, 2.5% (w/v) formaldehyde, 2% (w/v) potassium antimonate K[Sb(OH) 6] in 0.1 M K 2HPO 4 buffer with an osmolarity (calculated theoretically) of 0.45 and 1.26 osmol. The concentrations of ethylene in all spaceflight canisters were significantly higher than in the ground control canisters. Seedling growth was reduced in the spaceflight-exposed plants. Additionally, the spaceflight-exposed plants exhibited progressive vacuolation in the root apex cells, particularly in the columella cells, to a greater degree than the ground controls. Plasmolysis was observed in columella cells of spaceflight roots fixed in solutions with relatively high osmolarity (1.26 osmol). The appearance of plasmolysis permitted the evaluation of the water status of cells. The water potential of the spaceflight cells was higher than the surrounding fixative solution. A decrease in osmotic potential and/or an increase in turgor potential may have induced increases in cell water potential. However, the plasmolysed (i.e. nonturgid) cells implied that increases in water potential were accompanied with a decrease in osmotic potential. In such cells changes in vacuolation may have been involved to maintain turgor pressure or may have been a result of intensification of other vacuolar functions like digestion and storage

  17. Human gastric cancer, Helicobacter pylori and bracken carcinogens: A connecting hypothesis.

    Science.gov (United States)

    Oliveros-Bastidas, Alberto; Calcagno-Pissarelli, María Pía; Naya, Marlene; Ávila-Núñez, Jorge Luis; Alonso-Amelot, Miguel E

    2016-03-01

    Long term infection of Helicobacter pylori (Hp) virulent strains is a key factor in the genesis of human gastric cancer, and so are certain dietary proinflammatory and genotoxic compounds. Carcinogenic bracken fern (Pteridium spp.) is one of these. Toxins from this plant are consumed as bracken culinary preparations, through milk and meat of bracken-exposed livestock, and drain waters from bracken swards. Bracken toxin ptaquiloside (PtQ), a suspected human carcinogen, elicits complex responses in animals leading to death. PtQ and Hp might cooperate in gastric pathologies. This paper presents an hypothesis on PtQ-Hp association leading to the enhancement of carcinogenesis in the human gastric environment that might explain the high gastric cancer incidence and death rates among Hp-infected people living in bracken zones at two levels: (1) The macroscopic scale comprising the flow of PtQ in the human diet. (2) the microscopic scale encompassing (A) gastric luminal medium; (B) gastric mucus structure and mucin degradation elicited by Hp; (C) bacterial pH gradient modification of the gastric mucosa that favors PtQ survival and its penetration into epithelial tissue; (D) combined PtQ/Hp effects on gastric immune and inflammatory responses; (E) PtQ-Hp complementary activity at selected cell signaling cascades and genome disturbance.

  18. The Vtc proteins in vacuole fusion: coupling NSF activity to V(0) trans-complex formation

    DEFF Research Database (Denmark)

    Müller, Oliver; Bayer, Martin J; Peters, Christopher

    2002-01-01

    vacuole system has revealed two subsequent molecular events: trans-complex formation of V-ATPase proteolipid sectors (V(0)) and release of LMA1 from the membrane. We have now identified a hetero-oligomeric membrane integral complex of vacuolar transporter chaperone (Vtc) proteins integrating these events......, LMA1 release, but dispensible for all preceding steps, including V(0) trans-complex formation. This suggests that Vtc3p might act close to or at fusion pore opening. We propose that Vtc proteins may couple ATP-dependent NSF activity to a subset of V(0) sectors in order to activate them for V(0) trans...

  19. Systems analysis of metabolism in Helicobacter pylori

    OpenAIRE

    Correia, Daniela M.

    2014-01-01

    Tese de doutoramento em Engenharia Química e Biológica Helicobacter pylori is associated with gastric diseases, such as gastritis, peptic and duodenal ulcers, mucosa associated lymphoid tissue lymphoma and gastric adenocarcinomas. Despite more than half of the global population being infected with this bacterium, not all individuals will develop clinical symptoms. Nevertheless, its association with gastric cancer, the high infection rate, as well as the failures on eradication ...

  20. Helicobacter Pylori Infection and Pediatric Asthma

    OpenAIRE

    Abdullah Karimi; Koroush Fakhimi Derakhshan; Farid Imanzadeh; Mohamad Rezaei; Zahra Cavoshzadeh; Saeid Maham

    2013-01-01

    Objective Childhood infectious diseases are one of the most known environmental pathogenic causes of childhood asthma. The high prevalence of both Helicobacter pylori infection and asthma in our country prompted us to assess anyprobable association between them in childhood. Methods This cross-sectional study recruited 196 children aged 6 to 12 years old comprising 98 asthmatic (case group) and 98 healthy (control group) individuals. Urea breath test was performed for all of the children and ...

  1. H. PYLORI AND GASTROPATHY IN DIABETES

    OpenAIRE

    Koval V. Yu.

    2015-01-01

    Over the last 11 years the prevalence of diabetes in Ukraine has increased rapidly – from 1.8 to 2.8%. This especially concerns children and adolescents. The progression and compensation of the diabetes depend on many factors. In today’s medical literature the role of Helicobacter рylori in the development and progression of diabetic gastroparesis is widely discussed. In addition, the issue of the necessity and feasibility of H. Pylori eradication in these patients is ...

  2. Helicobacter (Campylobacter) pylori and Acid Peptic Diseases

    OpenAIRE

    Sigmund Kradjen; Philip Sherman

    1990-01-01

    Helicobacter pylori is a spiral-shaped Gram-negative bacteria implicated as a cause of histological gastritis, contributing to peptic ulcer disease and perhaps playing a role in gastric cancer in humans. The organism is found worldwide; the prevalence of infection increases with age; and colonization probably persists for life. Diagnostic approaches chat have been used include tissue stains, culture of stomach biopsy specimens, labelled-urea breath tests and serology. It is ...

  3. [Second Brazilian Consensus Conference on Helicobacter pylori infection].

    Science.gov (United States)

    Coelho, Luiz Gonzaga Vaz; Zaterka, Schlioma

    2005-01-01

    Significant progress has been obtained since the First Brazilian Consensus Conference on H. pylori Infection held in 1995, in Belo Horizonte, MG, and justify a second meeting to establish updated guidelines on the current management of H. pylori infection. The Second Brazilian Consensus Conference on H. pylori Infection was organized by the Brazilian Federation of Gastroenterology and Brazilian Nucleus for the Study of Helicobacter and took place on June, 19-20, 2004 in São Paulo, SP. Thirty six delegates coming from 15 different Brazilian states including gastroenterologists, pathologists, microbiologists and pediatricians undertook the meeting. The participants were allocated in one the five main topics of the meeting: H. pylori and dyspepsia, H. pylori and NSAIDs, H. pylori and gastroesophageal reflux disease, H. pylori treatment, and H. pylori retreatment. Seventy per cent and more votes were considered as acceptance for the final statement. The results were presented during a special session on the VI Brazilian Week of Digestive System, in Recife, PE (October 2004), and this publication represents the summary of the main recommendations and conclusions emerged from the meeting.

  4. Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia.

    NARCIS (Netherlands)

    Vollaard, A.M.; Verspaget, H.W.; Ali, S.; Visser, L.G.; Veenendaal, R.A.; Asten, H.A.G.H. van; Widjaja, S.; Surjadi, C.; Dissel, J.T. van

    2006-01-01

    We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration

  5. Helicobacter pylori and cancer among adults in Uganda

    Directory of Open Access Journals (Sweden)

    Owens Marilyn

    2006-11-01

    Full Text Available Abstract Data from Africa on infection with Helicobacter pylori (H. pylori are sparse. Therefore, as part of an epidemiological study of cancer in Uganda, we investigated the prevalence and determinants of antibodies against H. pylori among 854 people with different cancer types and benign tumours. Patients were recruited from hospitals in Kampala, Uganda, interviewed about various demographic and lifestyle factors and tested for antibodies against H. pylori. In all patients combined, excluding those with stomach cancer (which has been associated with H. pylori infection, the prevalence of antibodies was 87% (723/833 overall, but declined with increasing age (p = 0.02 and was lower among people who were HIV seropositive compared to seronegative (p H. pylori antibodies (odds ratio 0.8, 95% confidence intervals 0.2–2.9, p = 0.7; estimated using all other patients as controls, with adjustment for age, sex and HIV serostatus. No other cancer site or type was significantly associated with anti-H. pylori antibodies. The prevalence of H. pylori reported here is broadly in accord with results from other developing countries, although the determinants of infection and its' role in the aetiology of gastric cancer in Uganda remain unclear.

  6. Molecular Mechanisms of Antibiotic Resistance in Helicobacter pylori

    NARCIS (Netherlands)

    M.M. Gerrits (Monique)

    2004-01-01

    textabstractAn estimated 4 to 5 million individuals in the Netherlands are actively infected with Helicobacter pylori. Eradication of this bacterium becomes more difficult as the prevalence of antibiotic resistance is increasing worldwide. Most H. pylori infections are now diagnosed by non-invasi

  7. Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia.

    NARCIS (Netherlands)

    Vollaard, A.M.; Verspaget, H.W.; Ali, S.; Visser, L.G.; Veenendaal, R.A.; Asten, H.A.G.H. van; Widjaja, S.; Surjadi, C.; Dissel, J.T. van

    2006-01-01

    We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration

  8. Helicobacter pylori infection generates genetic instability in gastric cells

    DEFF Research Database (Denmark)

    Machado, Ana Manuel Dantas; Figueiredo, Céu; Seruca, Raquel

    2010-01-01

    The discovery that Helicobacter pylori is associated with gastric cancer has led to numerous studies that investigate the mechanisms by which H. pylori induces carcinogenesis. Gastric cancer shows genetic instability both in nuclear and mitochondrial DNA, besides impairment of important DNA repair...

  9. Helicobacter pylori in out-patients of a general practitioner

    DEFF Research Database (Denmark)

    Rothenbacher, D; Bode, G; Winz, T

    1997-01-01

    Data on prevalence and determinants of Helicobacter pylori infection in well-defined populations are scarce. We investigated the prevalence and determinants of active H. pylori infection in a population of out-patients attending a general practitioner in Southern Germany. Infection status...

  10. Epidemiology of the Antibiotic Resistance of Helicobacter pylori in Canada

    Directory of Open Access Journals (Sweden)

    Carlo A Fallone

    2000-01-01

    Full Text Available BACKGROUND: The rate of Helicobacter pylori resistance to antibiotics determines the cure rate of treatment regimens containing such antibiotics. AIMS: To review the literature to determine the rates of H pylori resistance to metronidazole and clarithromycin in Canada, and whether these rates vary in different regions of Canada.

  11. Seroprevalence of Helicobacter pylori in female Vietnamese immigrants to Korea

    Institute of Scientific and Technical Information of China (English)

    Su Jung Baik; Sun Young Yi; Hye Sook Park; Bo Hyun Park

    2012-01-01

    AIM: To investigate the seroprevalence of Helicobacter pylori (H. pylori) and its relationship to nutritional factors in ^emale Vietnamese immigrants to Korea.METHODS: A total of 390 female immigrants from Vietnam and 206 Korean male spouses participated in the study. Blood samples from 321 female immigrants and 201 Korean male spouses were analyzed for H. pylori antibodies. Data on age, sex, alcohol consumption, smoking status, dietary nutritional factors and gastrointestinal symptoms were collected using questionnaires. The daily intakes of the following nutrients were estimated: energy, protein, niacin, lipid, fiber, calcium, iron, sodium, potassium, zinc, folate, cholesterol, and vitamins A, B1, B2, B6, C and E.RESULTS: The prevalence of H. pylori positivity was lower in the immigrants than in age-matched Korean females (55.7% vs 71.4%, respectively; P < 0.0001) and the domestic population of Vietnam. The prevalence of H. pylori positivity among married couples was 31.7% for both spouses. There were no statistically significant differences in the incidence of smoking, amount of alcohol consumed, or nutritional factors between the H. pylori-positive and negative groups.CONCLUSION: The prevalence of H. pylori positivity was lower among female Vietnamese immigrants than among Korean females. Nutritional factors did not differ between the H. pylori-positive and negative groups.

  12. Helicobacter pylori gastritis in HIV-infected patients: a review.

    Science.gov (United States)

    Nevin, Daniel T; Morgan, Christopher J; Graham, David Y; Genta, Robert M

    2014-10-01

    The risk factors for acquiring Helicobacter pylori and Human Immunodeficiency Virus (HIV) infections are different: H. pylori is transmitted by gastro- or fecal-oral routes and is associated with low socioeconomic conditions, while HIV is transmitted through sexual intercourse, infected body fluids, and transplacentally. If the host responses to these infections were independent, the prevalence of H. pylori should be similar in HIV-infected and non-infected patients. Yet, several studies have detected a lower prevalence of H. pylori in patients with HIV infection, whereas other studies found either no differences or greater rates of H. pylori infection in HIV-positive subjects. To review studies that addressed the issue of these two simultaneous infections and attempt to determine whether reliable conclusions can be drawn from this corpus of often contrasting evidence. Electronic literature search for relevant publications, followed by manual search of additional citations from extracted articles. The initial search yielded 44 publications; after excluding case reports, reviews, narrowly focused articles, and duplicate reports, there remained 29 articles, which are the corpus of this review. With one exception, all studies reported higher rates of H. pylori infection in HIV-negative subjects. Five studies also examined the CD4 lymphocyte counts and found an inverse correlation between the degree of immunosuppression and the prevalence of active H. pylori infection. Current evidence suggests that it is likely that H. pylori needs a functional immune system to successfully and persistently colonize the human gastric mucosa. © 2014 John Wiley & Sons Ltd.

  13. Helicobacter pylori and oral pathology: Relationship with the gastric infection

    Science.gov (United States)

    Adler, Isabel; Muiño, Andrea; Aguas, Silvia; Harada, Laura; Diaz, Mariana; Lence, Adriana; Labbrozzi, Mario; Muiño, Juan Manuel; Elsner, Boris; Avagnina, Alejandra; Denninghoff, Valeria

    2014-01-01

    Helicobacter pylori (H. pylori) has been found in the oral cavity and stomach, and its infection is one of the most frequent worldwide. We reviewed the literature and conducted a Topic Highlight, which identified studies reporting an association between H. pylori-infection in the oral cavity and H. pylori-positive stomach bacterium. This work was designed to determine whether H. pylori is the etiologic agent in periodontal disease, recurrent aphthous stomatitis (RAS), squamous cell carcinoma, burning and halitosis. Record selection focused on the highest quality studies and meta-analyses. We selected 48 articles reporting on the association between saliva and plaque and H. pylori-infection. In order to assess periodontal disease data, we included 12 clinical trials and 1 meta-analysis. We evaluated 13 published articles that addressed the potential association with RAS, and 6 with squamous cell carcinoma. Fourteen publications focused on our questions on burning and halitosis. There is a close relation between H. pylori infection in the oral cavity and the stomach. The mouth is the first extra-gastric reservoir. Regarding the role of H. pylori in the etiology of squamous cell carcinoma, no evidence is still available. PMID:25110422

  14. Flocculation of venereal disease research laboratory reagent by Helicobacter pylori.

    Science.gov (United States)

    Müller, K D; von Recklinghausen, G; Heintschel von Heinegg, E; Ansorg, R

    1991-09-01

    Helicobacter pylori strains flocculated with Venereal Disease Research Laboratory (VDRL) reagent in a glass slide test. Other pathogenic bacterial and fungal strains were nonreactive. The specific VDRL reaction property of Helicobacter pylori indicates an affinity of the cells for lipoidal substances, and can be used as a diagnostic aid for species identification.

  15. Helicobacter pylori and oral pathology: relationship with the gastric infection.

    Science.gov (United States)

    Adler, Isabel; Muiño, Andrea; Aguas, Silvia; Harada, Laura; Diaz, Mariana; Lence, Adriana; Labbrozzi, Mario; Muiño, Juan Manuel; Elsner, Boris; Avagnina, Alejandra; Denninghoff, Valeria

    2014-08-07

    Helicobacter pylori (H. pylori) has been found in the oral cavity and stomach, and its infection is one of the most frequent worldwide. We reviewed the literature and conducted a Topic Highlight, which identified studies reporting an association between H. pylori-infection in the oral cavity and H. pylori-positive stomach bacterium. This work was designed to determine whether H. pylori is the etiologic agent in periodontal disease, recurrent aphthous stomatitis (RAS), squamous cell carcinoma, burning and halitosis. Record selection focused on the highest quality studies and meta-analyses. We selected 48 articles reporting on the association between saliva and plaque and H. pylori-infection. In order to assess periodontal disease data, we included 12 clinical trials and 1 meta-analysis. We evaluated 13 published articles that addressed the potential association with RAS, and 6 with squamous cell carcinoma. Fourteen publications focused on our questions on burning and halitosis. There is a close relation between H. pylori infection in the oral cavity and the stomach. The mouth is the first extra-gastric reservoir. Regarding the role of H. pylori in the etiology of squamous cell carcinoma, no evidence is still available.

  16. Natural maternal transmission of H pylori in Mongolian gerbils

    Institute of Scientific and Technical Information of China (English)

    Jin-Uk Lee; Okjin Kim

    2006-01-01

    AIM: To investigate maternal H pylori infection status to determine the potential of maternal transmission.METHODS: In the present study, we examined these issues in an experimental murine model, which is a Mongolian gerbil model that has been reported as an optimal laboratory animal model to study H pylori.Pregnant Mongolian gerbils, infected experimentally with H pylori, were divided into as four groups. Following the experimental design, the stomachs of the mother and litters were isolated and assessed for transmission of H pylori at the prenatal period, parturition day, 1-wk old and 3-wk old respectively. Bacterial culture and polymerase chain reaction (PCR) were used to examine the presence of transmitted H pylori.RESULTS: All litters showed no transmission of H pylori during pregnancy and at parturition day. However, they revealed 33.3% and 69.6% at 1-wk and 3-wk of age respectively by PCR.CONCLUSION: These results suggested that vertical infection during the prenatal period or delivery procedure is unlikely as a route of mother-to-child H pylori infection.It may be that H pylori is acquired through breastfeeding, contaminated saliva and fecal-oral transmission during co-habitation.

  17. RECOVERY OF HELICOBACTER PYLORI FROM WATER BY IMMUNOMAGNETIC CAPTURE

    Science.gov (United States)

    A few reports have been written stating that H. pylori can be found in waters. However, detection and identification of H. pylori from water samples remains a very difficult task. One method that seems to work successfully is immunomagnetic capture. Water samples were concentr...

  18. What constitutes an Arabian Helicobacter pylori? Lessons from comparative genomics.

    Science.gov (United States)

    Kumar, Narender; Albert, M John; Al Abkal, Hanan; Siddique, Iqbal; Ahmed, Niyaz

    2017-02-01

    Helicobacter pylori, the human gastric pathogen, causes a variety of gastric diseases ranging from mild gastritis to gastric cancer. While the studies on H. pylori are dominated by those based on either East Asian or Western strains, information regarding H. pylori strains prevalent in the Middle East remains scarce. Therefore, we carried out whole-genome sequencing and comparative analysis of three H. pylori strains isolated from three native Arab, Kuwaiti patients. H. pylori strains were sequenced using Illumina platform. The sequence reads were filtered and draft genomes were assembled and annotated. Various pathogenicity-associated regions and phages present within the genomes were identified. Phylogenetic analysis was carried out to determine the genetic relatedness of Kuwaiti strains to various lineages of H. pylori. The core genome content and virulence-related genes were analyzed to assess the pathogenic potential. The three genomes clustered along with HpEurope strains in the phylogenetic tree comprising various H. pylori lineages. A total of 1187 genes spread among various functional classes were identified in the core genome analysis. The three genomes possessed a complete cagPAI and also retained most of the known outer membrane proteins as well as virulence-related genes. The cagA gene in all three strains consisted of an AB-C type EPIYA motif. The comparative genomic analysis of Kuwaiti H. pylori strains revealed a European ancestry and a high pathogenic potential. © 2016 John Wiley & Sons Ltd.

  19. Epidemiology of Helicobacter pylori Infection and Public Health Implications

    Science.gov (United States)

    Goh, Khean-Lee; Chan, Wah-Kheong; Shiota, Seiji; Yamaoka, Yoshio

    2013-01-01

    This review summarizes studies on the epidemiology and public health implications of Helicobacter pylori published in peer-reviewed journals from April 2010 through March 2011. Prevalence rates vary widely between different geographical regions and ethnic groups. An interesting study from the USA identified the degree of African ancestry as an independent predictor of H. pylori infection. Two studies have demonstrated early childhood as the period of transmission of infection and identified an infected sibling as an important risk factor. An oral–oral route of spread has been substantiated with several studies showing the presence of H. pylori in the oral cavity. Studies have shown the presence of H. pylori in drinking water and the role of poor living conditions and sanitation in H. pylori infection, supporting an oral–fecal route of spread. Screening for H. pylori as a gastric cancer prescreening strategy has been described in Japan, and the importance of H. pylori eradication as a gastric cancer–prevention strategy has now been further emphasized in Japanese guidelines. Two studies have shown a decrease in the burden of dyspepsia and peptic ulcer disease with H. pylori eradication. PMID:21896079

  20. SURVIVAL OF HELICOBACTER PYLORI IN A NATURAL FRESHWATER ENVIRONMENT

    Science.gov (United States)

    The mode by which Helicobacter pylori, the causative agent of most gastric ulcers, is transmitted remains undetermined. Epidemiological evidence suggests these organisms are waterborne; however, H. pylori has rarely been grown from potential water sources. This may be due to th...