scholarly journals Blue light emitting diodes enhance the antivirulence effects of Curcumin against Helicobacter pylori

2020 ◽  
Vol 69 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Homa Darmani ◽  
Ehda A.M. Smadi ◽  
Sereen M.B. Bataineh
Keyword(s):  
Helicobacter Pylori ◽  
Blue Light ◽  
Type Species ◽  
Light Emitting Diodes ◽  
Light Therapy ◽  
Content Type ◽  
Light Emitting ◽  
Link Type ◽  
Urease Production ◽  
H Pylori

Introduction. Growing concern about the increasing frequency of resistance of Helicobacter pylori to the available antimicrobial agents worldwide has encouraged the search for new strategies in treating and eradicating H. pylori infections. Endoscopic blue-light therapy has been used in patients with H. pylori gastritis with limited success due to subsequent repopulation with H. pylori . Clinical trials using Curcumin could not eradicate infection either. Aim. We studied the effect of blue light emitting diodes (LEDs) in conjunction with Curcumin on H. pylori , since this has not been previously reported. Methodology. We examined the effect of Curcumin with and without irradiation with blue LEDs on the viability of H. pylori and four key factors important for colonization and establishment of H. pylori infection, namely urease production, motility, adhesion and biofilm formation. Results. We found that a combination of Curcumin and blue LEDs caused significant reductions in viability, urease production, motility, haemagglutination activity, as well as increased disruption of mature preformed biofilms of H. pylori , in comparison to Curcumin alone (P<0.0001), at sublethal concentrations of Curcumin. Conclusion. Targeting the virulence factors of H. pylori with blue LED photoactivated Curcumin would theoretically cripple this pathogen from colonizing and causing tissue damage and perhaps overcome the problem of repopulation with H. pylori that often occurs following endoscopic blue-light therapy.

scholarly journals Genome-wide association study of gastric cancer- and duodenal ulcer-derived Helicobacter pylori strains reveals discriminatory genetic variations and novel oncoprotein candidates

2021 ◽  
Vol 7 (11) ◽  
Author(s):  
Vo Phuoc Tuan ◽  
Koji Yahara ◽  
Ho Dang Quy Dung ◽  
Tran Thanh Binh ◽  
Pham Huu Tung ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Duodenal Ulcer ◽  
Helicobacter Pylori ◽  
Type Species ◽  
Genetic Variations ◽  
Genome Wide Association ◽  
Content Type ◽  
Link Type ◽  
Genome Wide ◽  
H Pylori

Genome-wide association studies (GWASs) can reveal genetic variations associated with a phenotype in the absence of any hypothesis of candidate genes. The problem of false-positive sites linked with the responsible site might be bypassed in bacteria with a high homologous recombination rate, such as Helicobacter pylori , which causes gastric cancer. We conducted a small-sample GWAS (125 gastric cancer cases and 115 controls) followed by prediction of gastric cancer and control (duodenal ulcer) H. pylori strains. We identified 11 single nucleotide polymorphisms (eight amino acid changes) and three DNA motifs that, combined, allowed effective disease discrimination. They were often informative of the underlying molecular mechanisms, such as electric charge alteration at the ligand-binding pocket, alteration in subunit interaction, and mode-switching of DNA methylation. We also identified three novel virulence factors/oncoprotein candidates. These results provide both defined targets for further informatic and experimental analyses to gain insights into gastric cancer pathogenesis and a basis for identifying a set of biomarkers for distinguishing these H. pylori -related diseases.

scholarly journals Protective effects of Helicobacter pylori membrane vesicles against stress and antimicrobial agents

Microbiology ◽  
2020 ◽  
Vol 166 (8) ◽  
pp. 751-758 ◽  
Author(s):  
Benjamin Oliver Murray ◽  
Robin Andrew Dawson ◽  
Lolwah Mohammad Alsharaf ◽  
Jody Anne Winter
Keyword(s):  
Helicobacter Pylori ◽  
Type Species ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Host Cells ◽  
Content Type ◽  
Link Type ◽  
H Pylori

Outer-membrane vesicles (OMVs) produced by Helicobacter pylori deliver bacterial components to host cells, provide a mechanism for stabilization of secreted components and may allow the bacteria to exert ‘long-range’ effects in the gastric niche, promoting persistence. In addition to their well-characterized host cell interactions, membrane vesicles improve stress survival in other bacterial species, and are constitutively produced by both pathogenic and non-pathogenic bacteria. We aimed to determine whether OMVs could improve H. pylori survival of a range of stressors. The effects of purified OMVs on the resistance of H. pylori to a range of environmental and antimicrobial stresses were determined using growth curves and survival assays. Addition of purified OMVs to H. pylori cultures provided dose-dependent protection against hydrogen peroxide-mediated killing. Supplementation with OMVs also partially protected H. pylori against the bactericidal effects of the antibiotics clarithromycin and levofloxacin, but not against amoxicillin nor metronidazole. Addition of purified OMVs allowed H. pylori to grow in the presence of inhibitory concentrations of the antimicrobial peptide LL-37. In the presence of 50 µg OMVs ml−1, significantly enhanced H. pylori growth was observed at higher LL-37 concentrations compared with lower LL-37 concentrations, suggesting that OMV–LL-37 interactions might facilitate release of growth-promoting nutrients. Taken together, these data indicate that production of membrane vesicles could help H. pylori to survive exposure to antibiotics and host antimicrobial defences during infection.

scholarly journals Staphylococcus borealis sp. nov., isolated from human skin and blood

2020 ◽  
Vol 70 (12) ◽  
pp. 6067-6078
Author(s):  
Maria Pain ◽  
Runa Wolden ◽  
Daniel Jaén-Luchoro ◽  
Francisco Salvà-Serra ◽  
Beatriz Piñeiro Iglesias ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Novel Species ◽  
Culture Collection ◽  
Rrna Gene ◽  
Phylogenetic Distance ◽  
Content Type ◽  
Link Type ◽  
Urease Production

When analysing a large cohort of Staphylococcus haemolyticus , using whole-genome sequencing, five human isolates (four from the skin and one from a blood culture) with aberrant phenotypic and genotypic traits were identified. They were phenotypically similar with yellow colonies, nearly identical 16S rRNA gene sequences and initially speciated as S. haemolyticus based on 16S rRNA gene sequence and MALDI-TOF MS. However, compared to S. haemolyticus , these five strains demonstrate: (i) considerable phylogenetic distance with an average nucleotide identity <95 % and inferred DNA–DNA hybridization <70  %; (ii) a pigmented phenotype; (iii) urease production; and (iv) different fatty acid composition. Based on the phenotypic and genotypic results, we conclude that these strains represent a novel species, for which the name Staphylococcus borealis sp. nov. is proposed. The novel species belong to the genus Staphylococcus and is coagulase- and oxidase-negative and catalase-positive. The type strain, 51-48T, is deposited in the Culture Collection University of Gothenburg (CCUG 73747T) and in the Spanish Type Culture Collection (CECT 30011T).

Anti-proliferation effect of blue light-emitting diodes against antibiotic-resistant Helicobacter pylori

2018 ◽  
Vol 33 (8) ◽  
pp. 1492-1499 ◽  
Author(s):  
Jianwei Ma ◽  
Takahiro Hiratsuka ◽  
Tsuyoshi Etoh ◽  
Junko Akada ◽  
Hajime Fujishima ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Blue Light ◽  
Light Emitting Diodes ◽  
Antibiotic Resistant ◽  
Light Emitting

scholarly journals N-terminal region of Helicobacter pylori CagA induces IL-8 production in gastric epithelial cells via the β1 integrin receptor

2020 ◽  
Vol 69 (3) ◽  
pp. 457-464 ◽  
Author(s):  
Bangwei Zeng ◽  
Chu Chen ◽  
Qingfeng Yi ◽  
Xiaoyan Zhang ◽  
Xiangyan Wu ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Epithelial Cells ◽  
Type Species ◽  
Terminal Region ◽  
Enzyme Linked Immunosorbent Assay ◽  
Gastric Epithelial Cells ◽  
Ags Cells ◽  
Content Type ◽  
Link Type ◽  
Prokaryotic Expression System

Introduction. Helicobacter pylori is associated with gastrointestinal disease, most notably gastric cancer. Cytotoxin-associated antigen A (CagA), an important virulence factor for H. pylori pathogenicity, induces host cells to release inflammatory factors, especially interleukin-8 (IL-8). The mechanism by which C-terminal CagA induces IL-8 production has been studied extensively, but little is known about the role of the N-terminus. Aim. To investigate the effect of CagA303–456aa (a peptide in the N-terminal CagA) on IL-8 production by gastric epithelial cells. Methodology. CagA303-456aa was produced by a prokaryotic expression system and purified by Strep-tag affinity chromatography. An integrin β1 (ITGB1)-deficient AGS cell line was constructed using the CRISPR/Cas9 technique, and NCTC 11637 cagA and/or cagL knockout mutants were constructed via homologous recombination. The levels of IL-8 production were determined by enzyme-linked immunosorbent assay (ELISA), and p38 and ERK1/2 phosphorylation were examined by Western blot. Results. CagA303-456aa induced IL-8 expression by AGS cells. IL-8 induction by CagA303-456aawas specifically inhibited by ITGB1 deficiency. Notably, CagA303-456aa activated the phosphorylation of both p38 and ERK1/2, and blocking p38 and ERK1/2 activity significantly reduced IL-8 induction by CagA303-456aa. ITGB1 deficiency also inhibited the activation of p38 phosphorylation by CagA303-456aa. Finally, experiments in CagA and/or CagL knockout bacterial lines demonstrated that extracellular CagA might induce IL-8 production by AGS cells. Conclusion. Residues 303–456 of the N-terminal region of CagA induce IL-8 production via a CagA303-456–ITGB1–p38–IL-8 pathway, and ERK1/2 is also involved in the release of IL-8. Extracellular CagA might induce IL-8 production before translocation into AGS cells.

scholarly journals Agent-Based Modeling Demonstrates How Local Chemotactic Behavior Can Shape Biofilm Architecture

mSphere ◽  
2019 ◽  
Vol 4 (3) ◽  
Author(s):  
Emily G. Sweeney ◽  
Andrew Nishida ◽  
Alexandra Weston ◽  
Maria S. Bañuelos ◽  
Kristin Potter ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Three Dimensional ◽  
Structural Features ◽  
Agent Based Modeling ◽  
Emergent Properties ◽  
Cellular Interactions ◽  
Biofilm Growth ◽  
Content Type ◽  
Agent Based ◽  
H Pylori

ABSTRACTBacteria are often found living in aggregated multicellular communities known as biofilms. Biofilms are three-dimensional structures that confer distinct physical and biological properties to the collective of cells living within them. We used agent-based modeling to explore whether local cellular interactions were sufficient to give rise to global structural features of biofilms. Specifically, we asked whether chemorepulsion from a self-produced quorum-sensing molecule, autoinducer-2 (AI-2), was sufficient to recapitulate biofilm growth and cellular organization observed for biofilms ofHelicobacter pylori, a common bacterial resident of human stomachs. To carry out this modeling, we modified an existing platform, Individual-based Dynamics of Microbial Communities Simulator (iDynoMiCS), to incorporate three-dimensional chemotaxis, planktonic cells that could join or leave the biofilm structure, and cellular production of AI-2. We simulated biofilm growth of previously characterizedH. pyloristrains with various AI-2 production and sensing capacities. Using biologically plausible parameters, we were able to recapitulate both the variation in biofilm mass and cellular distributions observed with these strains. Specifically, the strains that were competent to chemotax away from AI-2 produced smaller and more heterogeneously spaced biofilms, whereas the AI-2 chemotaxis-defective strains produced larger and more homogeneously spaced biofilms. The model also provided new insights into the cellular demographics contributing to the biofilm patterning of each strain. Our analysis supports the idea that cellular interactions at small spatial and temporal scales are sufficient to give rise to larger-scale emergent properties of biofilms.IMPORTANCEMost bacteria exist in aggregated, three-dimensional structures called biofilms. Although biofilms play important ecological roles in natural and engineered settings, they can also pose societal problems, for example, when they grow in plumbing systems or on medical implants. Understanding the processes that promote the growth and disassembly of biofilms could lead to better strategies to manage these structures. We had previously shown thatHelicobacter pyloribacteria are repulsed by high concentrations of a self-produced molecule, AI-2, and thatH. pylorimutants deficient in AI-2 sensing form larger and more homogeneously spaced biofilms. Here, we used computer simulations of biofilm formation to show that localH. pyloribehavior of repulsion from high AI-2 could explain the overall architecture ofH. pyloribiofilms. Our findings demonstrate that it is possible to change global biofilm organization by manipulating local cell behaviors, which suggests that simple strategies targeting cells at local scales could be useful for controlling biofilms in industrial and medical settings.

Blue light-emitting diodes in hair regrowth: the first prospective study

2021 ◽  
Author(s):  
G. Lodi ◽  
M. Sannino ◽  
G. Cannarozzo ◽  
A. Giudice ◽  
E. Del Duca ◽  
...  
Keyword(s):  
Prospective Study ◽  
Blue Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
Hair Regrowth
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