151
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Rafiq M, Saleem M, Hanif M, Maqsood MR, Rama NH, Lee KH, Seo SY. Synthesis and Biological Activities of Some New 3,6-Disubstituted 1,2,4-Triazolo[3,4-b]1,3,4-thiadiazole Derivatives. B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.12.3943] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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152
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Costa AM, Leite M, Seruca R, Figueiredo C. Adherens junctions as targets of microorganisms: a focus on Helicobacter pylori. FEBS Lett 2012; 587:259-65. [PMID: 23262219 DOI: 10.1016/j.febslet.2012.12.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 12/07/2012] [Accepted: 12/10/2012] [Indexed: 12/14/2022]
Abstract
Mucosal epithelia are targeted by several microorganisms as a way of adhesion, internalization, and/or exploitation of the host properties to induce disease. Helicobacter pylori are worldwide prevalent bacteria that colonize the human stomach. Persistent infection of the gastric mucosa with H. pylori and concurrent chronic gastritis are risk factors for ulcer disease and gastric carcinoma. Therefore, interactions at the H. pylori-epithelial interface are important to understand the pathogenesis of these bacteria and the host responses that contribute to disease development. Here, we provide an overview of the interactions between microorganisms and the adherens junctions with an emphasis on H. pylori.
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Affiliation(s)
- Angela Margarida Costa
- IPATIMUP - Institute of Molecular Pathology and Immunology of the University of Porto,Portugal
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153
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Adsul LK, Bandgar BP, Chavan HV, Jalde SS, Dhakane VD, Shirfule AL. Synthesis and biological evaluation of novel series of aminopyrimidine derivatives as urease inhibitors and antimicrobial agents. J Enzyme Inhib Med Chem 2012; 28:1316-23. [PMID: 23230954 DOI: 10.3109/14756366.2012.740477] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A novel series of carbazole substituted aminopyrimidines (5a-p) were synthesized and screened for their in vitro urease inhibition and antimicrobial activity. Among the compounds, 4-(2,4-dichlorophenyl)-6-(9-methyl-9H-carbazol-3-yl)-pyrimidin-2-amine (5i) was found to be the most potent showing urease inhibitory activity with an IC50 value 19.4 ± 0.43 µM. Compounds 5c, 5g, 5j and 5o showed good activity against all selected bacterial strains and compounds 5b, 5c, 5m and 5o showed good activity against selected fungal strains. All the compounds were subjected for ADME predictions by computational method.
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Affiliation(s)
- Laxman K Adsul
- Medicinal Chemistry Research Laboratory, School of Chemical Sciences, Solapur University , Solapur, Maharashtra , India
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154
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Saeed A, Zaib S, Pervez A, Mumtaz A, Shahid M, Iqbal J. Synthesis, molecular docking studies, and in vitro screening of sulfanilamide-thiourea hybrids as antimicrobial and urease inhibitors. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0376-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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155
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Abstract
Animal models are important tools for studies of human disease, but developing these models is a particular challenge with regard to organisms with restricted host ranges, such as the human stomach pathogen Helicobacter pylori. In most cases, H. pylori infects the stomach for many decades before symptoms appear, distinguishing it from many bacterial pathogens that cause acute infection. To model chronic infection in the mouse, a human clinical isolate was selected for its ability to survive for 2 months in the mouse stomach, and the resulting strain, MSD132, colonized the mouse stomach for at least 28 weeks. During selection, the cagY component of the Cag type IV secretion system was mutated, disrupting a key interaction with host cells. Increases in both bacterial persistence and bacterial burden occurred prior to this mutation, and a mixed population of cagY(+) and cagY mutant cells was isolated from a single mouse, suggesting that mutations accumulate during selection and that factors in addition to the Cag apparatus are important for murine adaptation. Diversity in both alleles and genes is common in H. pylori strains, and natural competence mediates a high rate of interstrain genetic exchange. Mutations of the Com apparatus, a membrane DNA transporter, and DprA, a cytosolic competence factor, resulted in reduced persistence, although initial colonization was normal. Thus, exchange of DNA between genetically heterogeneous H. pylori strains may improve chronic colonization. The strains and methods described here will be important tools for defining both the spectrum of mutations that promote murine adaptation and the genetic program of chronic infection.
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156
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Kharat AN, Bakhoda A, Bruno G, Rudbari HA. Urease inhibitory activities of ZnBr2 and ZnI2 complexes of terpyridine derivatives: Systematic investigation of aryl substituents on urease inhibitory activities. Polyhedron 2012. [DOI: 10.1016/j.poly.2012.07.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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157
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Shi DH, Cao ZL, Liu WW, Xu RB, Zhang N, Gao LL, Zhang Q. Synthesis and Crystal Structures of Schiff Base Nickel(II) Complexes With Biological Activity. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/15533174.2012.680157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Da-Hua Shi
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
- b Jiangsu Key Laboratory of Marine Biotechnology , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Zhi-Ling Cao
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Wei-Wei Liu
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Rui-Bo Xu
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Na Zhang
- c Department of Chemistry and Chemical Engineering , Liaoning Normal University , Dalian , P. R. China
| | - Liu-Liu Gao
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Qian Zhang
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
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158
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Shi DH, Zhang N, Liu WW, Gao LL, Zhang Q, You ZL. Synthesis, Crystal Structures, and Biological Activity of Cu(II), Mn(III), and Fe(III) Complexes Derived from N,N’-Bis(4-methoxysalicylidene)ethylenediamine. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/15533174.2012.684236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Da-Hua Shi
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
- b Jiangsu Key Laboratory of Marine Biotechnology , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Na Zhang
- c Department of Chemistry , Liaoning Normal University , Dalian , P. R. China
| | - Wei-Wei Liu
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Liu-Liu Gao
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Qian Zhang
- a School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Zhong-Lu You
- c Department of Chemistry , Liaoning Normal University , Dalian , P. R. China
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159
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Saleem M, Rafiq M, Hanif M, Rama NH, Seo SY, Lee KH. Synthesis, Urease and Acetylcholine Esterase Inhibition Activities of Some 1,4-Disubstituted Thiosemicarbazides and their 2,5-Disubstituted Thiadiazoles. B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.8.2741] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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160
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Synthesis, biological evaluation, and molecular docking studies of 2,5-substituted-1,4-benzoquinone as novel urease inhibitors. Bioorg Med Chem 2012; 20:4889-94. [DOI: 10.1016/j.bmc.2012.07.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 07/01/2012] [Accepted: 07/02/2012] [Indexed: 11/23/2022]
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161
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Yahiro K, Satoh M, Nakano M, Hisatsune J, Isomoto H, Sap J, Suzuki H, Nomura F, Noda M, Moss J, Hirayama T. Low-density lipoprotein receptor-related protein-1 (LRP1) mediates autophagy and apoptosis caused by Helicobacter pylori VacA. J Biol Chem 2012; 287:31104-15. [PMID: 22822085 DOI: 10.1074/jbc.m112.387498] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In Helicobacter pylori infection, vacuolating cytotoxin (VacA)-induced mitochondrial damage leading to apoptosis is believed to be a major cause of cell death. It has also been proposed that VacA-induced autophagy serves as a host mechanism to limit toxin-induced cellular damage. Apoptosis and autophagy are two dynamic and opposing processes that must be balanced to regulate cell death and survival. Here we identify the low-density lipoprotein receptor-related protein-1 (LRP1) as the VacA receptor for toxin-induced autophagy in the gastric epithelial cell line AZ-521, and show that VacA internalization through binding to LRP1 regulates the autophagic process including generation of LC3-II from LC3-I, which is involved in formation of autophagosomes and autolysosomes. Knockdown of LRP1 and Atg5 inhibited generation of LC3-II as well as cleavage of PARP, a marker of apoptosis, in response to VacA, whereas caspase inhibitor, benzyloxycarbonyl-VAD-fluoromethylketone (Z-VAD-fmk), and necroptosis inhibitor, Necrostatin-1, did not inhibit VacA-induced autophagy, suggesting that VacA-induced autophagy via LRP1 binding precedes apoptosis. Other VacA receptors such as RPTPα, RPTPβ, and fibronectin did not affect VacA-induced autophagy or apoptosis. Therefore, we propose that the cell surface receptor, LRP1, mediates VacA-induced autophagy and apoptosis.
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Affiliation(s)
- Kinnosuke Yahiro
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
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162
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Cui YM, Dong XW, Chen W, Wang WJ, Li YG, Zhu HL. Synthesis, inhibitory activity and molecular docking studies of two Cu(II) complexes against Helicobacter pylori urease. J Enzyme Inhib Med Chem 2012; 27:528-32. [DOI: 10.3109/14756366.2011.599065] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yong-Ming Cui
- Engineering Research Center for Clean Production of Textile Printing, Ministry of Education, Wuhan Textile University,
Wuhan P.R. China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University,
Nanjing P.R. China
| | - Xiong-Wei Dong
- Engineering Research Center for Clean Production of Textile Printing, Ministry of Education, Wuhan Textile University,
Wuhan P.R. China
| | - Wu Chen
- Engineering Research Center for Clean Production of Textile Printing, Ministry of Education, Wuhan Textile University,
Wuhan P.R. China
| | - Wen-Jun Wang
- College of Life Science, South-Central University for Nationalities,
Wuhan P.R. China
| | - Yu-Guang Li
- Engineering Research Center for Clean Production of Textile Printing, Ministry of Education, Wuhan Textile University,
Wuhan P.R. China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University,
Nanjing P.R. China
| | - Hai-Liang Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University,
Nanjing P.R. China
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163
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Crystal structure of Helicobacter pylori neutrophil-activating protein with a di-nuclear ferroxidase center in a zinc or cadmium-bound form. Biochem Biophys Res Commun 2012; 422:745-50. [PMID: 22618234 DOI: 10.1016/j.bbrc.2012.05.073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 05/12/2012] [Indexed: 11/23/2022]
Abstract
Helicobacter pylori neutrophil-activating protein (HP-NAP) is a Dps-like iron storage protein forming a dodecameric shell, and promotes adhesion of neutrophils to endothelial cells. The crystal structure of HP-NAP in a Zn(2+)- or Cd(2+)-bound form reveals the binding of two zinc or two cadmium ions and their bridged water molecule at the ferroxidase center (FOC). The two zinc ions are coordinated in a tetrahedral manner to the conserved residues among HP-NAP and Dps proteins. The two cadmium ions are coordinated in a trigonal-bipyramidal and distorted octahedral manner. In both structures, the second ion is more weakly coordinated than the first. Another zinc ion is found inside of the negatively-charged threefold-related pore, which is suitable for metal ions to pass through.
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164
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The Helicobacter pylori autotransporter ImaA (HP0289) modulates the immune response and contributes to host colonization. Infect Immun 2012; 80:2286-96. [PMID: 22566509 DOI: 10.1128/iai.00312-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The human pathogen Helicobacter pylori employs a diverse collection of outer membrane proteins to colonize, persist, and drive disease within the acidic gastric environment. In this study, we sought to elucidate the function of the host-induced gene HP0289, which encodes an uncharacterized outer membrane protein. We first generated an isogenic H. pylori mutant that lacks HP0289 and found that the mutant has a colonization defect in single-strain infections and is greatly outcompeted in mouse coinfection experiments with wild-type H. pylori. Furthermore, we used protease assays and biochemical fractionation coupled with an HP0289-targeted peptide antibody to verify that the HP0289 protein resides in the outer membrane. Our previous findings showed that the HP0289 promoter is upregulated in the mouse stomach, and here we demonstrate that HP0289 expression is induced under acidic conditions in an ArsRS-dependent manner. Finally, we have shown that the HP0289 mutant induces greater expression of the chemokine interleukin-8 (IL-8) and the cytokine tumor necrosis factor alpha (TNF-α) in gastric carcinoma cells (AGS). Similarly, transcription of the IL-8 homolog keratinocyte-derived chemokine (KC) is elevated in murine infections with the HP0289 mutant than in murine infections with wild-type H. pylori. On the basis of this phenotype, we renamed HP0289 ImaA for immunomodulatory autotransporter protein. Our work has revealed that genes induced in vivo play an important role in H. pylori pathogenesis. Specifically, the outer membrane protein ImaA modulates a component of the host inflammatory response, and thus may allow H. pylori to fine tune the host immune response based on ImaA expression.
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165
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Shi DH, Wang XL, Liu WW, Jin H. Synthesis, Crystal Structures, and Biological Activity of Schiff Base Zinc(II) Complexes Derived From (2-piperidin-1-ylethyl)-(1-pyridin-2-ylethylidene)amine. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/15533174.2011.613083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Da-Hua Shi
- a School of Chemical Engineering, Huaihai Institute of Technology , Lianyungang , P. R. China
- b Jiangsu Key Laboratory of Marine Biotechnology, Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Xiao-Ling Wang
- c Department of Chemistry , Liaoning Normal University , Dalian , P. R. China
| | - Wei-Wei Liu
- a School of Chemical Engineering, Huaihai Institute of Technology , Lianyungang , P. R. China
| | - Hui Jin
- a School of Chemical Engineering, Huaihai Institute of Technology , Lianyungang , P. R. China
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166
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Synthesis, structures, and urease inhibitory activities of oxovanadium(V) complexes with Schiff bases. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2011.11.039] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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167
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Kim IJ, Blanke SR. Remodeling the host environment: modulation of the gastric epithelium by the Helicobacter pylori vacuolating toxin (VacA). Front Cell Infect Microbiol 2012; 2:37. [PMID: 22919629 PMCID: PMC3417592 DOI: 10.3389/fcimb.2012.00037] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 03/05/2012] [Indexed: 12/13/2022] Open
Abstract
Virulence mechanisms underlying Helicobacter pylori persistence and disease remain poorly understood, in part, because the factors underlying disease risk are multifactorial and complex. Among the bacterial factors that contribute to the cumulative pathophysiology associated with H. pylori infections, the vacuolating cytotoxin (VacA) is one of the most important. Analogous to a number of H. pylori genes, the vacA gene exhibits allelic mosaicism, and human epidemiological studies have revealed that several families of toxin alleles are predictive of more severe disease. Animal model studies suggest that VacA may contribute to pathogenesis in several ways. VacA functions as an intracellular-acting protein exotoxin. However, VacA does not fit the current prototype of AB intracellular-acting bacterial toxins, which elaborate modulatory effects through the action of an enzymatic domain translocated inside host cells. Rather, VacA may represent an alternative prototype for AB intracellular acting toxins that modulate cellular homeostasis by forming ion-conducting intracellular membrane channels. Although VacA seems to form channels in several different membranes, one of the most important target sites is the mitochondrial inner membrane. VacA apparently take advantage of an unusual intracellular trafficking pathway to mitochondria, where the toxin is imported and depolarizes the inner membrane to disrupt mitochondrial dynamics and cellular energy homeostasis as a mechanism for engaging the apoptotic machinery within host cells. VacA remodeling of the gastric environment appears to be fine-tuned through the action of the Type IV effector protein CagA which, in part, limits the cytotoxic effects of VacA in cells colonized by H. pylori.
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Affiliation(s)
- Ik-Jung Kim
- Department of Microbiology, Institute for Genomic Biology, University of Illinois, Urbana IL, USA
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168
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Sycuro LK, Wyckoff TJ, Biboy J, Born P, Pincus Z, Vollmer W, Salama NR. Multiple peptidoglycan modification networks modulate Helicobacter pylori's cell shape, motility, and colonization potential. PLoS Pathog 2012; 8:e1002603. [PMID: 22457625 PMCID: PMC3310797 DOI: 10.1371/journal.ppat.1002603] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 01/05/2012] [Indexed: 12/14/2022] Open
Abstract
Helical cell shape of the gastric pathogen Helicobacter pylori has been suggested to promote virulence through viscosity-dependent enhancement of swimming velocity. However, H. pylori csd1 mutants, which are curved but lack helical twist, show normal velocity in viscous polymer solutions and the reason for their deficiency in stomach colonization has remained unclear. Characterization of new rod shaped mutants identified Csd4, a DL-carboxypeptidase of peptidoglycan (PG) tripeptide monomers and Csd5, a putative scaffolding protein. Morphological and biochemical studies indicated Csd4 tripeptide cleavage and Csd1 crosslinking relaxation modify the PG sacculus through independent networks that coordinately generate helical shape. csd4 mutants show attenuation of stomach colonization, but no change in proinflammatory cytokine induction, despite four-fold higher levels of Nod1-agonist tripeptides in the PG sacculus. Motility analysis of similarly shaped mutants bearing distinct alterations in PG modifications revealed deficits associated with shape, but only in gel-like media and not viscous solutions. As gastric mucus displays viscoelastic gel-like properties, our results suggest enhanced penetration of the mucus barrier underlies the fitness advantage conferred by H. pylori's characteristic shape.
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Affiliation(s)
- Laura K. Sycuro
- Molecular and Cellular Biology Graduate Program, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Timna J. Wyckoff
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Science and Mathematics, University of Minnesota, Morris, Minnesota, United States of America
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Petra Born
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Zachary Pincus
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, United States of America
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Nina R. Salama
- Molecular and Cellular Biology Graduate Program, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
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169
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Chang CS, Liu JF, Lin HJ, Lin CD, Tang CH, Lu DY, Sing YT, Chen LY, Kao MC, Kuo SC, Lai CH. Synthesis and bioevaluation of novel 3,4,5-trimethoxybenzylbenzimidazole derivatives that inhibit Helicobacter pylori-induced pathogenesis in human gastric epithelial cells. Eur J Med Chem 2012; 48:244-54. [DOI: 10.1016/j.ejmech.2011.12.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 11/16/2011] [Accepted: 12/13/2011] [Indexed: 01/25/2023]
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170
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ANKOLEKAR CHANDRAKANT, JOHNSON KEVIN, PINTO MARCIA, JOHNSON DAVID, LABBE RONALDG, GREENE DUANE, SHETTY KALIDAS. FERMENTATION OF WHOLE APPLE JUICE USINGLACTOBACILLUS ACIDOPHILUSFOR POTENTIAL DIETARY MANAGEMENT OF HYPERGLYCEMIA, HYPERTENSION, AND MODULATION OF BENEFICIAL BACTERIAL RESPONSES. J Food Biochem 2011. [DOI: 10.1111/j.1745-4514.2011.00596.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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171
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Sokmen BB, Gumrukcuoglu N, Ugras S, Ugras HI, Yanardag R. Synthesis, antibacterial, antielastase, antiurease and antioxidant activities of new methoxy substitued bis-1,2,4-triazole derivatives. J Enzyme Inhib Med Chem 2011; 28:72-7. [DOI: 10.3109/14756366.2011.631536] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Bahar Bilgin Sokmen
- Department of Chemistry, Faculty of Arts and Sciences, Giresun University,
Giresun, Turkey
| | - Nurhan Gumrukcuoglu
- Vocational School of Health Sciences, Karadeniz Technical University,
Trabzon, Turkey
| | - Serpil Ugras
- Department of Biology, Faculty of Arts and Sciences, Giresun University,
Giresun, Turkey
| | - Halil Ibrahim Ugras
- Department of Chemistry, Faculty of Arts and Sciences, Giresun University,
Giresun, Turkey
| | - Refiye Yanardag
- Department of Chemistry Faculty of Engineering, Istanbul University,
Istanbul, Turkey
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172
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Sohn SH, Lee YC. The genome-wide expression profile of gastric epithelial cells infected by naturally occurring cagA isogenic strains of Helicobacter pylori. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2011; 32:382-389. [PMID: 22004957 DOI: 10.1016/j.etap.2011.08.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/13/2011] [Accepted: 08/06/2011] [Indexed: 05/31/2023]
Abstract
Helicobacter pylori (H. pylori) is associated with the development of gastric adenocarcinoma and lymphoma. However, the mechanisms through which H. pylori induces gastric mucosal lesions are not well defined. This study was conducted to evaluate the effect of the oncoprotein CagA on gastric cancer cells using whole-genome expression arrays. Human gastric epithelial (AGS) cells were incubated with CagA-positive H. pylori strains (147C (phosphorylated CagA) or 147A (dephosphorylated CagA)), and total protein and RNA were collected. The effects of phosphorylated and unphosphorylated CagA on AGS cells were then evaluated using Western blotting and microarray analysis. The expression levels of the genome profiles of AGS cells infected with 147A were compared with those of AGS cells infected with 147C. The expression profiles of the differentially expressed genes were grouped, and their expression patterns were validated via quantitative real-time PCR. Up- and down-regulated genes mainly included epithelial mesenchymal transition (EMT)-related genes. The results of the microarray analysis revealed that phosphorylated and unphosphorylated CagA may affect EMT in part through gene expression. This suggests that the intracellularly translocated CagA may be involved in EMT, resulting in differential expression of genes independent on the phosphorylation status of CagA.
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Affiliation(s)
- Sung-Hwa Sohn
- Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
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173
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Rassow J. Helicobacter pylori vacuolating toxin A and apoptosis. Cell Commun Signal 2011; 9:26. [PMID: 22044628 PMCID: PMC3266207 DOI: 10.1186/1478-811x-9-26] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 11/01/2011] [Indexed: 12/16/2022] Open
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.
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Affiliation(s)
- Joachim Rassow
- Ruhr-Universität Bochum, Institut für Physiologische Chemie, Medizinische Fakultät, Gebäude MA3, D-44780 Bochum, Germany.
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174
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Ankolekar C, Pinto M, Greene D, Shetty K. Phenolic Bioactive Modulation byLactobacillus acidophilusMediated Fermentation of Cherry Extracts for Anti-Diabetic Functionality,Helicobacter pyloriinhibition and ProbioticBifidobacterium longumStimulation. FOOD BIOTECHNOL 2011. [DOI: 10.1080/08905436.2011.617255] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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175
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Zhang N, Huang CY, Shi DH, You ZL. Unprecedented preparation of bis-Schiff bases and their manganese(III) complexes with urease inhibitory activity. INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.06.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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176
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Hopf PS, Ford RS, Zebian N, Merkx-Jacques A, Vijayakumar S, Ratnayake D, Hayworth J, Creuzenet C. Protein glycosylation in Helicobacter pylori: beyond the flagellins? PLoS One 2011; 6:e25722. [PMID: 21984942 PMCID: PMC3184161 DOI: 10.1371/journal.pone.0025722] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 09/09/2011] [Indexed: 12/13/2022] Open
Abstract
Glycosylation of flagellins by pseudaminic acid is required for virulence in Helicobacter pylori. We demonstrate that, in H. pylori, glycosylation extends to proteins other than flagellins and to sugars other than pseudaminic acid. Several candidate glycoproteins distinct from the flagellins were detected via ProQ-emerald staining and DIG- or biotin- hydrazide labeling of the soluble and outer membrane fractions of wild-type H. pylori, suggesting that protein glycosylation is not limited to the flagellins. DIG-hydrazide labeling of proteins from pseudaminic acid biosynthesis pathway mutants showed that the glycosylation of some glycoproteins is not dependent on the pseudaminic acid glycosylation pathway, indicating the existence of a novel glycosylation pathway. Fractions enriched in glycoprotein candidates by ion exchange chromatography were used to extract the sugars by acid hydrolysis. High performance anion exchange chromatography with pulsed amperometric detection revealed characteristic monosaccharide peaks in these extracts. The monosaccharides were then identified by LC-ESI-MS/MS. The spectra are consistent with sugars such as 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (Pse5Ac7Ac) previously described on flagellins, 5-acetamidino-7-acetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (Pse5Am7Ac), bacillosamine derivatives and a potential legionaminic acid derivative (Leg5AmNMe7Ac) which were not previously identified in H. pylori. These data open the way to the study of the mechanism and role of protein glycosylation on protein function and virulence in H. pylori.
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Affiliation(s)
- Patrick S. Hopf
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Rachel S. Ford
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Najwa Zebian
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Alexandra Merkx-Jacques
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Somalinga Vijayakumar
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Dinath Ratnayake
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Jacqueline Hayworth
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Carole Creuzenet
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
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177
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Mori N, Ishikawa C, Senba M. Induction of CD69 expression by cagPAI-positive Helicobacter pylori infection. World J Gastroenterol 2011; 17:3691-9. [PMID: 21990950 PMCID: PMC3181454 DOI: 10.3748/wjg.v17.i32.3691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/01/2011] [Accepted: 03/08/2011] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate and elucidate the molecular mechanism that regulates inducible expression of CD69 by Helicobacter pylori (H. pylori) infection.
METHODS: The expression levels of CD69 in a T-cell line, Jurkat, primary human peripheral blood mononuclear cells (PBMCs), and CD4+ T cells, were assessed by immunohistochemistry, reverse transcription polymerase chain reaction, and flow cytometry. Activation of CD69 promoter was detected by reporter gene. Nuclear factor (NF)-κB activation in Jurkat cells infected with H. pylori was evaluated by electrophoretic mobility shift assay. The role of NF-κB signaling in H. pylori-induced CD69 expression was analyzed using inhibitors of NF-κB and dominant-negative mutants. The isogenic mutants with disrupted cag pathogenicity island (cagPAI) and virD4 were used to elucidate the role of cagPAI-encoding type IV secretion system and CagA in CD69 expression.
RESULTS: CD69 staining was detected in mucosal lymphocytes and macrophages in specimens of patients with H. pylori-positive gastritis. Although cagPAI-positive H. pylori and an isogenic mutant of virD4 induced CD69 expression, an isogenic mutant of cagPAI failed to induce this in Jurkat cells. H. pylori also induced CD69 expression in PBMCs and CD4+ T cells. The activation of the CD69 promoter by H. pylori was mediated through NF-κB. Transfection of dominant-negative mutants of IκBs, IκB kinases, and NF-κB-inducing kinase inhibited H. pylori-induced CD69 activation. Inhibitors of NF-κB suppressed H. pylori-induced CD69 mRNA expression.
CONCLUSION: The results suggest that H. pylori induces CD69 expression through the activation of NF-κB. cagPAI might be relevant in the induction of CD69 expression in T cells. CD69 in T cells may play a role in H. pylori-induced gastritis.
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178
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In silico quest for putative drug targets in Helicobacter pylori HPAG1: molecular modeling of candidate enzymes from lipopolysaccharide biosynthesis pathway. J Mol Model 2011; 18:1855-66. [PMID: 21850571 DOI: 10.1007/s00894-011-1204-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 07/26/2011] [Indexed: 01/05/2023]
Abstract
Aimed at identification and structural characterization of novel putative therapeutic targets in H. pylori, the etiological agent of numerous gastrointestinal diseases including peptic ulcer and gastric cancer, the present study comprised of three phases. First, through subtractive analysis of metabolic pathways of Helicobacter pylori HPAG1 and human, as documented in the KEGG database, 11 pathogen-specific pathways were identified. Next, all proteins involved in these pathogen-specific pathways were scrutinized in search of promising targets and the study yielded 25 candidate target proteins that are likely to be essential for the pathogen viability, but have no homolog in human. The lipopolysaccharide (LPS) biosynthesis pathway was found to be the largest contributor (nine proteins) to this list of candidate proteins. Considering the importance of LPS in H. pylori virulence, 3D structural models of three predicted target enzymes of this pathway, namely 2-dehydro-3-deoxy-phosphooctonate aldolase, UDP-3-O-[3-hydroxymyristoyl] N-acetylglucosamine deacetylase and Phosphoheptose isomerase, were then built up using the homology modeling approaches. Binding site analysis and docking of the known biological substrate PEP to 2-dehydro-3-deoxyphosphooctonate aldolase revealed the potential binding pocket present in the single monomeric form of the enzyme and identified 11 amino acid residues that might play the key roles in this protein-ligand interaction.
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179
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Preparation and structural characterization of hetero-dinuclear Schiff base copper(II)–zinc(II) complexes and their inhibition studies on Helicobacter pylori urease. Polyhedron 2011. [DOI: 10.1016/j.poly.2011.05.048] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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180
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Suzuki M, Kiga K, Kersulyte D, Cok J, Hooper CC, Mimuro H, Sanada T, Suzuki S, Oyama M, Kozuka-Hata H, Kamiya S, Zou QM, Gilman RH, Berg DE, Sasakawa C. Attenuated CagA oncoprotein in Helicobacter pylori from Amerindians in Peruvian Amazon. J Biol Chem 2011; 286:29964-72. [PMID: 21757722 DOI: 10.1074/jbc.m111.263715] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Population genetic analyses of bacterial genes whose products interact with host tissues can give new understanding of infection and disease processes. Here we show that strains of the genetically diverse gastric pathogen Helicobacter pylori from Amerindians from the remote Peruvian Amazon contain novel alleles of cagA, a major virulence gene, and reveal distinctive properties of their encoded CagA proteins. CagA is injected into the gastric epithelium where it hijacks pleiotropic signaling pathways, helps Hp exploit its special gastric mucosal niche, and affects the risk that infection will result in overt gastroduodenal diseases including gastric cancer. The Amerindian CagA proteins contain unusual but functional tyrosine phosphorylation motifs and attenuated CRPIA motifs, which affect gastric epithelial proliferation, inflammation, and bacterial pathogenesis. Amerindian CagA proteins induced less production of IL-8 and cancer-associated Mucin 2 than did those of prototype Western or East Asian strains and behaved as dominant negative inhibitors of action of prototype CagA during mixed infection of Mongolian gerbils. We suggest that Amerindian cagA is of relatively low virulence, that this may have been selected in ancestral strains during infection of the people who migrated from Asia into the Americas many thousands of years ago, and that such attenuated CagA proteins could be useful therapeutically.
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Affiliation(s)
- Masato Suzuki
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
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181
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Prakash S, Tomaro-Duchesneau C, Saha S, Cantor A. The gut microbiota and human health with an emphasis on the use of microencapsulated bacterial cells. J Biomed Biotechnol 2011; 2011:981214. [PMID: 21772792 PMCID: PMC3134400 DOI: 10.1155/2011/981214] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 02/16/2011] [Accepted: 04/11/2011] [Indexed: 12/11/2022] Open
Abstract
The gut microbiota plays a crucial role in maintaining health. Alterations of the gut bacterial population have been associated with a number of diseases. Past and recent studies suggest that one can positively modify the contents of the gut microbiota by introducing prebiotics, probiotics, synbiotics, and other therapeutics. This paper focuses on probiotic modulation of the gut microbiota by their delivery to the lower gastrointestinal tract (GIT). There are numerous obstacles to overcome before microorganisms can be utilized as therapeutics. One important limitation is the delivery of viable cells to the lower GIT without a significant loss of cell viability and metabolic features through the harsh conditions of the upper GIT. Microencapsulation has been shown to overcome this, with various types of microcapsules available for resolving this limitation. This paper discusses the gut microbiota and its role in disease, with a focus on microencapsulated probiotics and their potentials and limitations.
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Affiliation(s)
- Satya Prakash
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine, McGill University, 3775 University Street, Montreal, QC, Canada H3A 2B4.
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182
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Ankolekar C, Johnson D, Pinto MDS, Johnson K, Labbe R, Shetty K. Inhibitory potential of tea polyphenolics and influence of extraction time against Helicobacter pylori and lack of inhibition of beneficial lactic acid bacteria. J Med Food 2011; 14:1321-9. [PMID: 21663484 DOI: 10.1089/jmf.2010.0237] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Tea polyphenolics such as catechins are known to have the potential to inhibit many bacterial pathogens. Helicobacter pylori has been identified as an etiologic agent in the development of gastric ulcer, peptic ulcer, gastritis, and many other stomach-related diseases. In this study, we investigated the effect of 9 tea extracts--3 different brands representing 4 different processed types (white, green, oolong, and black)--on the inhibition of H. pylori. Extraction times of 2 and 5 minutes were compared. Most 5-minute extracts showed H. pylori inhibition, whereas 2-minute extracts only of Choice darjeeling black and Tazo white showed inhibition. No recovery was observed after the addition of 0.5 and 5 mM proline, indicating that tea polyphenols do not inhibit H. pylori by inhibition of proline oxidation via proline dehydrogenase. Extracts that showed inhibition were further evaluated for their effect on beneficial lactic acid bacteria. None of the samples showed inhibition, suggesting that tea might be able to inhibit H. pylori without affecting the beneficial lactic acid bacteria. High-performance liquid chromatography indicated the presence of gallic acid, quercetin, caffeine, and tea catechins (including catechin, epicatechin, and epigallocatechin) in all the tea samples. Our study indicates that tea can be potentially used as a low-cost dietary support to combat H. pylori-linked gastric diseases without affecting the beneficial intestinal bacteria.
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Affiliation(s)
- Chandrakant Ankolekar
- Laboratory of Food Biotechnology, Department of Food Science, Chenoweth Laboratory, University of Massachusetts, Amherst, Massachusetts, USA
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183
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Ishijima N, Suzuki M, Ashida H, Ichikawa Y, Kanegae Y, Saito I, Borén T, Haas R, Sasakawa C, Mimuro H. BabA-mediated adherence is a potentiator of the Helicobacter pylori type IV secretion system activity. J Biol Chem 2011; 286:25256-64. [PMID: 21596743 DOI: 10.1074/jbc.m111.233601] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Chronic infection of Helicobacter pylori in the stomach mucosa with translocation of the bacterial cytotoxin-associated gene A (CagA) effector protein via the cag-Type IV secretion system (TFSS) into host epithelial cells are major risk factors for gastritis, gastric ulcers, and cancer. The blood group antigen-binding adhesin BabA mediates the adherence of H. pylori to ABO/Lewis b (Le(b)) blood group antigens in the gastric pit region of the human stomach mucosa. Here, we show both in vitro and in vivo that BabA-mediated binding of H. pylori to Le(b) on the epithelial surface augments TFSS-dependent H. pylori pathogenicity by triggering the production of proinflammatory cytokines and precancer-related factors. We successfully generated Le(b)-positive cell lineages by transfecting Le(b)-negative cells with several glycosyltransferase genes. Using these established cell lines, we found increased mRNA levels of proinflammatory cytokines (CCL5 and IL-8) as well as precancer-related factors (CDX2 and MUC2) after the infection of Le(b)-positive cells with WT H. pylori but not with babA or TFSS deletion mutants. This increased mRNA expression was abrogated when Le(b)-negative cells were infected with WT H. pylori. Thus, H. pylori can exploit BabA-Le(b) binding to trigger TFSS-dependent host cell signaling to induce the transcription of genes that enhance inflammation, development of intestinal metaplasia, and associated precancerous transformations.
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Affiliation(s)
- Nozomi Ishijima
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
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184
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You ZL, Cui YM, Ma YP, Wang C, Zhou XS, Li K. Synthesis, characterization and urease inhibitory activity of oxovanadium(V) complexes with similar Schiff bases. INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.01.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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185
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Paulo L, Oleastro M, Gallardo E, Queiroz JA, Domingues F. Anti-Helicobacter pylori and urease inhibitory activities of resveratrol and red wine. Food Res Int 2011. [DOI: 10.1016/j.foodres.2011.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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186
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Romi B, Soldaini E, Pancotto L, Castellino F, Del Giudice G, Schiavetti F. Helicobacter pylori induces activation of human peripheral γδ+ T lymphocytes. PLoS One 2011; 6:e19324. [PMID: 21559446 PMCID: PMC3084806 DOI: 10.1371/journal.pone.0019324] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 03/25/2011] [Indexed: 11/19/2022] Open
Abstract
Helicobacter pylori is a gram-negative bacterium that causes gastric and duodenal diseases in humans. Despite a robust antibody and cellular immune response, H. pylori infection persists chronically. To understand if and how H. pylori could modulate T cell activation, in the present study we investigated in vitro the interaction between H. pylori and human T lymphocytes freshly isolated from peripheral blood of H. pylori-negative donors. A direct interaction of live, but not killed bacteria with purified CD3+ T lymphocytes was observed by microscopy and confirmed by flow cytometry. Live H. pylori activated CD3+ T lymphocytes and predominantly γδ+ T cells bearing the TCR chain Vδ2. Upon interaction with H. pylori, these cells up-regulated the activation molecule CD69 and produced cytokines (such as TNFα, IFNγ) and chemokines (such as MIP-1β, RANTES) in a non-antigen-specific manner. This activation required viable H. pylori and was not exhibited by other gram-negative bacteria. The cytotoxin-associated antigen-A (CagA), was at least partially responsible of this activation. Our results suggest that H. pylori can directly interact with T cells and modulate the response of γδ+ T cells, thereby favouring an inflammatory environment which can contribute to the chronic persistence of the bacteria and eventually to the gastric pathology.
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Affiliation(s)
- Benedetta Romi
- Novartis Vaccines and Diagnostics Research Center, Siena, Italy
| | | | - Laura Pancotto
- Novartis Vaccines and Diagnostics Research Center, Siena, Italy
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187
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Tiwari SK, Sharma V, Sharma VK, Gopi M, Saikant R, Nandan A, Bardia A, Gunisetty S, Katikala P, Habeeb MA, Khan AA, Habibullah CM. Phylogenetic analysis, based on EPIYA repeats in the cagA gene of Indian Helicobacter pylori, and the implications of sequence variation in tyrosine phosphorylation motifs on determining the clinical outcome. Genet Mol Biol 2011; 34:280-5. [PMID: 21734830 PMCID: PMC3115323 DOI: 10.1590/s1415-47572011005000003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Accepted: 10/14/2010] [Indexed: 01/03/2023] Open
Abstract
The population of India harbors one of the world's most highly diverse gene pools, owing to the influx of successive waves of immigrants over regular periods in time. Several phylogenetic studies involving mitochondrial DNA and Y chromosomal variation have demonstrated Europeans to have been the first settlers in India. Nevertheless, certain controversy exists, due to the support given to the thesis that colonization was by the Austro-Asiatic group, prior to the Europeans. Thus, the aim was to investigate pre-historic colonization of India by anatomically modern humans, using conserved stretches of five amino acid (EPIYA) sequences in the cagA gene of Helicobacter pylori. Simultaneously, the existence of a pathogenic relationship of tyrosine phosphorylation motifs (TPMs), in 32 H. pylori strains isolated from subjects with several forms of gastric diseases, was also explored. High resolution sequence analysis of the above described genes was performed. The nucleotide sequences obtained were translated into amino acids using MEGA (version 4.0) software for EPIYA. An MJ-Network was constructed for obtaining TPM haplotypes by using NETWORK (version 4.5) software. The findings of the study suggest that Indian H. pylori strains share a common ancestry with Europeans. No specific association of haplotypes with the outcome of disease was revealed through additional network analysis of TPMs.
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Affiliation(s)
- Santosh K Tiwari
- Centre for Liver Research and Diagnostics, Deccan College of Medical Sciences, Kanchanbagh, Hyderabad, Andhra Pradesh, India
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188
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Complex cellular responses of Helicobacter pylori-colonized gastric adenocarcinoma cells. Infect Immun 2011; 79:2362-71. [PMID: 21402757 DOI: 10.1128/iai.01350-10] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Helicobacter pylori is an important class I carcinogen that persistently infects the human gastric mucosa to induce gastritis, gastric ulceration, and gastric cancer. H. pylori pathogenesis strongly depends on pathogenic factors, such as VacA (vacuolating cytotoxin A) or a specialized type IV secretion system (T4SS), which injects the oncoprotein CagA (cytotoxin-associated gene A product) into the host cell. Since access to primary gastric epithelial cells is limited, many studies on the complex cellular and molecular mechanisms of H. pylori were performed in immortalized epithelial cells originating from individual human adenocarcinomas. The aim of our study was a comparative analysis of 14 different human gastric epithelial cell lines after colonization with H. pylori. We found remarkable differences in host cell morphology, extent of CagA tyrosine phosphorylation, adhesion to host cells, vacuolization, and interleukin-8 (IL-8) secretion. These data might help in the selection of suitable cell lines to study host cell responses to H. pylori in vitro, and they imply that different host cell factors are involved in the determination of H. pylori pathogenesis. A better understanding of H. pylori-directed cellular responses can provide novel and more balanced insights into the molecular mechanisms of H. pylori-dependent pathogenesis in vivo and may lead to new therapeutic approaches.
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189
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Cioci G, Terradot L, Dian C, Mueller-Dieckmann C, Leonard G. Crystal structure of HP0721, a novel secreted protein from Helicobacter pylori. Proteins 2011; 79:1678-81. [PMID: 21365686 DOI: 10.1002/prot.22988] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/08/2010] [Accepted: 12/14/2010] [Indexed: 12/16/2022]
Affiliation(s)
- Gianluca Cioci
- Structural Biology Group, European Synchrotron Radiation Facility, Grenoble, France.
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190
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Gilbreath JJ, Cody WL, Merrell DS, Hendrixson DR. Change is good: variations in common biological mechanisms in the epsilonproteobacterial genera Campylobacter and Helicobacter. Microbiol Mol Biol Rev 2011; 75:84-132. [PMID: 21372321 PMCID: PMC3063351 DOI: 10.1128/mmbr.00035-10] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Microbial evolution and subsequent species diversification enable bacterial organisms to perform common biological processes by a variety of means. The epsilonproteobacteria are a diverse class of prokaryotes that thrive in diverse habitats. Many of these environmental niches are labeled as extreme, whereas other niches include various sites within human, animal, and insect hosts. Some epsilonproteobacteria, such as Campylobacter jejuni and Helicobacter pylori, are common pathogens of humans that inhabit specific regions of the gastrointestinal tract. As such, the biological processes of pathogenic Campylobacter and Helicobacter spp. are often modeled after those of common enteric pathogens such as Salmonella spp. and Escherichia coli. While many exquisite biological mechanisms involving biochemical processes, genetic regulatory pathways, and pathogenesis of disease have been elucidated from studies of Salmonella spp. and E. coli, these paradigms often do not apply to the same processes in the epsilonproteobacteria. Instead, these bacteria often display extensive variation in common biological mechanisms relative to those of other prototypical bacteria. In this review, five biological processes of commonly studied model bacterial species are compared to those of the epsilonproteobacteria C. jejuni and H. pylori. Distinct differences in the processes of flagellar biosynthesis, DNA uptake and recombination, iron homeostasis, interaction with epithelial cells, and protein glycosylation are highlighted. Collectively, these studies support a broader view of the vast repertoire of biological mechanisms employed by bacteria and suggest that future studies of the epsilonproteobacteria will continue to provide novel and interesting information regarding prokaryotic cellular biology.
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Affiliation(s)
- Jeremy J. Gilbreath
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - William L. Cody
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - D. Scott Merrell
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - David R. Hendrixson
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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191
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Harris P. Inmunidad y Helicobacter pylori. Medwave 2011. [DOI: 10.5867/medwave.2011.03.4950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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192
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Singh AK, Manns MP, Seidler U. Cytoprotective effects of acidosis via heat shock protein HSP27 against the anticancer drug doxorubicin. Cell Mol Life Sci 2011; 68:1041-51. [PMID: 20730553 PMCID: PMC11114508 DOI: 10.1007/s00018-010-0503-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 08/04/2010] [Accepted: 08/09/2010] [Indexed: 02/06/2023]
Abstract
Drug resistance continues to be a stumbling block in achieving better cure rates in several cancers. Doxorubicin is commonly used in treatment of a wide range of cancers. The aim of this study was to look into the mechanisms of how low ambient pH may contribute to down-regulation of apoptotic pathways in a gastric tumour cell line. Low pH culture conditions were found to dramatically prolong cell survival after doxorubicin treatment, an effect that was in part reversed by co-incubation with the specific p38 mitoge-activated protein kinase (MAP kinase) inhibitor SB203580, only mildly inhibited by blockade of the multi-drug resistance 1 (MDR1) transporter, but completely abolished by siRNA-mediated knockdown of the heat shock protein 27 (HSP27). In conclusion, acidic pH causes less accumulation of cytotoxic drug in the nucleus of adeno gastric carcinoma (AGS) cells and HSP27-dependent decrease in FasR-mediated gastric epithelial tumour cell apoptosis.
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Affiliation(s)
- Anurag Kumar Singh
- Department of Gastroenterolgy, Hepatology and Endocrinology, Hannover Medical School, Carl Neuberg Str. 1, Hannover, 30625 Germany
| | - Michael P. Manns
- Department of Gastroenterolgy, Hepatology and Endocrinology, Hannover Medical School, Carl Neuberg Str. 1, Hannover, 30625 Germany
| | - Ursula Seidler
- Department of Gastroenterolgy, Hepatology and Endocrinology, Hannover Medical School, Carl Neuberg Str. 1, Hannover, 30625 Germany
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193
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Apostolidis E, Kwon YI, Shinde R, Ghaedian R, Shetty K. Inhibition ofHelicobacter pyloriby Fermented Milk and Soymilk Using Select Lactic Acid Bacteria and Link to Enrichment of Lactic Acid and Phenolic Content. FOOD BIOTECHNOL 2011. [DOI: 10.1080/08905436.2011.547118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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194
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Wilson LG, Martinez VA, Schwarz-Linek J, Tailleur J, Bryant G, Pusey PN, Poon WCK. Differential dynamic microscopy of bacterial motility. PHYSICAL REVIEW LETTERS 2011; 106:018101. [PMID: 21231772 DOI: 10.1103/physrevlett.106.018101] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Indexed: 05/09/2023]
Abstract
We demonstrate a method for the fast, high-throughput characterization of the dynamics of active particles. Specifically, we measure the swimming speed distribution and motile cell fraction in Escherichia coli suspensions. By averaging over ∼10(4) cells, our method is highly accurate compared to conventional tracking, yielding a routine tool for motility characterization. We find that the diffusivity of nonmotile cells is enhanced in proportion to the concentration of motile cells.
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Affiliation(s)
- L G Wilson
- SUPA and COSMIC, School of Physics & Astronomy, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom
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195
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Zhu L, Do-Quang M, Lauga E, Brandt L. Locomotion by tangential deformation in a polymeric fluid. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:011901. [PMID: 21405707 DOI: 10.1103/physreve.83.011901] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Indexed: 05/30/2023]
Abstract
In several biologically relevant situations, cell locomotion occurs in polymeric fluids with Weissenberg number larger than 1. Here we present results of three-dimensional numerical simulations for the steady locomotion of a self-propelled body in a model polymeric (Giesekus) fluid at low Reynolds number. Locomotion is driven by steady tangential deformation at the surface of the body (the so-called squirming motion). In the case of a spherical squirmer, we show that the swimming velocity is systematically less than that in a Newtonian fluid, with a minimum occurring for Weissenberg numbers of order 1. The rate of work done by the swimmer always goes up compared to that occurring in the Newtonian solvent alone but is always lower than the power necessary to swim in a Newtonian fluid with the same viscosity. The swimming efficiency, defined as the ratio between the rate of work necessary to pull the body at the swimming speed in the same fluid and the rate of work done by swimming, is found to always be increased in a polymeric fluid. Further analysis reveals that polymeric stresses break the Newtonian front-back symmetry in the flow profile around the body. In particular, a strong negative elastic wake is present behind the swimmer, which correlates with strong polymer stretching, and its intensity increases with Weissenberg number and viscosity contrasts. The velocity induced by the squirmer is found to decay in space faster than in a Newtonian flow, with a strong dependence on the polymer relaxation time and viscosity. Our computational results are also extended to prolate spheroidal swimmers and smaller polymer stretching are obtained for slender shapes compared to bluff swimmers. The swimmer with an aspect ratio of two is found to be the most hydrodynamically efficient.
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Affiliation(s)
- Lailai Zhu
- Linné Flow Centre, KTH Mechanics, Stockholm, Sweden
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196
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Murtaza G, Badshah A, Said M, Khan H, Khan A, Khan S, Siddiq S, Choudhary MI, Boudreau J, Fontaine FG. Urease inhibition and anti-leishmanial assay of substituted benzoylguanidines and their copper(ii) complexes. Dalton Trans 2011; 40:9202-11. [DOI: 10.1039/c1dt10464k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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197
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Hakkim A, Fuchs TA, Martinez NE, Hess S, Prinz H, Zychlinsky A, Waldmann H. Activation of the Raf-MEK-ERK pathway is required for neutrophil extracellular trap formation. Nat Chem Biol 2010; 7:75-7. [PMID: 21170021 DOI: 10.1038/nchembio.496] [Citation(s) in RCA: 527] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 10/18/2010] [Indexed: 02/07/2023]
Abstract
The signaling mechanisms leading to the formation of neutrophil extracellular traps (NETs), relevant in infections, sepsis and autoimmune diseases, are poorly understood. Neutrophils are not amenable to studies with conventional genetic techniques. Using a new chemical genetic analysis we show that the Raf-MEK-ERK pathway is involved in NET formation through activation of NADPH oxidase and upregulation of antiapoptotic proteins. We identify potential targets for drugs addressing NET-associated diseases.
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Affiliation(s)
- Abdul Hakkim
- Department of Cellular Microbiology, Max Planck Institute for Infection Biology, Berlin
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198
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The immune modulating activity of the Helicobacter pylori HP-NAP: Friend or foe? Toxicon 2010; 56:1186-92. [DOI: 10.1016/j.toxicon.2009.09.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 09/30/2009] [Indexed: 12/20/2022]
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199
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Jones KR, Whitmire JM, Merrell DS. A Tale of Two Toxins: Helicobacter Pylori CagA and VacA Modulate Host Pathways that Impact Disease. Front Microbiol 2010; 1:115. [PMID: 21687723 PMCID: PMC3109773 DOI: 10.3389/fmicb.2010.00115] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 09/27/2010] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori is a pathogenic bacterium that colonizes more than 50% of the world's population, which leads to a tremendous medical burden. H. pylori infection is associated with such varied diseases as gastritis, peptic ulcers, and two forms of gastric cancer: gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma. This association represents a novel paradigm for cancer development; H. pylori is currently the only bacterium to be recognized as a carcinogen. Therefore, a significant amount of research has been conducted to identify the bacterial factors and the deregulated host cell pathways that are responsible for the progression to more severe disease states. Two of the virulence factors that have been implicated in this process are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA), which are cytotoxins that are injected and secreted by H. pylori, respectively. Both of these virulence factors are polymorphic and affect a multitude of host cellular pathways. These combined facts could easily contribute to differences in disease severity across the population as various CagA and VacA alleles differentially target some pathways. Herein we highlight the diverse types of cellular pathways and processes targeted by these important toxins.
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Affiliation(s)
- Kathleen R Jones
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
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200
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Polymorphisms in the intermediate region of VacA impact Helicobacter pylori-induced disease development. J Clin Microbiol 2010; 49:101-10. [PMID: 21084502 DOI: 10.1128/jcm.01782-10] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori is the etiological agent of diseases such as gastritis, gastric and duodenal ulcers, and two types of gastric cancers. While some insight has been gained into the etiology of these diverse manifestations, by and large, the reason that some individuals develop more severe disease remains elusive. Recent studies have focused on the roles of H. pylori toxins CagA and VacA on the disease process and have suggested that both toxins are intimately involved. Moreover, CagA and VacA are polymorphic within different H. pylori strains, and particular polymorphisms seem to show a correlation with the development of particular disease states. Among VacA polymorphisms, the intermediate region has recently been proposed to play a major role in disease outcome. In this article, we describe a detailed sequence analysis of the polymorphic intermediate region of vacA from strains obtained from a large South Korean population. We show that polymorphisms found at amino acid position 196 are associated with more severe disease manifestations. Additionally, polymorphisms found at amino acid position 231 are linked to disease in strains that carry the non-EPIYA-ABD allele of CagA. Collectively, these data help explain the impact of the VacA intermediate region on disease and lead to the hypothesis that there are allele-driven interactions between VacA and CagA.
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