Mechanisms of interacting <i>Helicobacter pylori</i> with gastric mucosal epithelium. II. A reaction of gastric epithelium on <i>Helicobacter pylori</i> colonization and persistence

Gastric and duodenal recurrent inflammatory diseases have a high prevalence, but the role played by microbes in its development remained unclear. However, the data published in 1983 by Marshall and Warren about isolating Helicobacter pylori from the stomach mucosa of the patient with gastritis and proposing relevant cultivation methods was the turning point in investigating etiology of the upper digestive tract inflammatory disorders. Moreover, it was shown that the majority of H. pylori spp. are found within the gastric lumen upon colonization, whereas around 20% of them are attached to the epithelial cells in the stomach. In addition, effects of interacting H. pylori with gastric epithelium and activation of some defense mechanisms due to bacterial colonization and spreading were analyzed. It was found that along with triggering pro-inflammatory response induced by proteins VacA as well as phosphorylated/unphosphorylated CagA, wherein the latter is able to induce a set of protective reactions H. pylori disrupts intercellular contacts, affects epithelial cell polarity and proliferation, and activates SHP-2 phosphatase resulting in emerging diverse types of cellular responses. The activation mechanisms for the mitogen-activated protein kinase (MAPK) pathway were discussed. The ability of H. pylori to regulate apoptosis, particularly via its suppression, by expressing ERK kinase and protein MCL1 facilitating bacterial survival in the gastric mucosa as well as beneficial effects related to bacterial circulation on gastric epithelial cell survival elicited by anti-apoptotic factors were also examined. Of note, persistence of H. pylori are mainly determined by activating transcriptional factors including NF-κB, NFAT, SRF, T-cell lymphoid enhancing factor (TCF/LEF), regulating activity of MCL1 protein, in turn, being one of the main anti-apoptotic factors, as well as induced production of the migration inhibitory factor (MIF). The role of VacA cytotoxin in triggering epithelial cell apoptosis via caspase-mediated pathways was also considered. Infection with H. pylori is accompanied by release of proinflammatory cytokine cocktail detected both in vitro and in vivo. In particular, bacterial urease activating transcriptional factor NF-κB was shown to play a crucial role in inducing cytokine production. Moreover, such signaling pathways may be activated after H. pylori is attached to the cognate receptor in the gastric epithelial surface by interacting with CD74 and MHC class II molecules. Finally, a role for various CD4+ T cell subsets, particularly type 17 T helper cells (Th17) in inducing immune response against H. pylori antigens in gastric mucosa was revealed were also discussed

Chiral S-stannyl dithiophosphates and dithiophosphonates on the basis of monoterpenols

Copyright © 2018 John Wiley & Sons, Ltd. Chiral S-tributylstannyl dithiophosphates and dithiophosphonates were obtained by the reactions of optically active dithiophosphoric and dithiophosphonic acids containing (S)-(–)-menthyl and (R)-(+)-menthyl substituents with gaseous ammonia and tributyl chlorostannane. The reactions of chiral ammonium dithiophosphate containing (1R)-endo-(+)-fenchyl substituent with tributyl chlorostannane or tetrachlorostannane result in corresponding S-tributylstannyl dithiophosphate or tetrakis(dithiophosphato)stannane. Molecular structure of ammonium O,O-di-(–)-menthyldithiophosphate was studied by X-ray single crystal diffraction. Bactericidal activity of S-tributylstannyl dithiophosphates was tested

Antibiotic Susceptibility Assessment of Helicobacter pylori Isolates by Disk-Diffusion Method

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Helicobacter pylori (H. pylori) infection is tightly associated with gastrointestinal disorders such as chronic gastritis, peptic ulcer, gastric MALToma, and gastric cancer. Decreased antibiotic susceptibility in H. pylori is a worldwide problem. Our objective was to determine in vitro antimicrobial susceptibility of H. pylori isolates obtained from gastric mucosa biopsies of children with H. pylori-associated gastroduodenal diseases using disk-diffusion method. A total 76 biopsy specimens were studied; antibiotic susceptibility was assessed in case of 30 children in whom H. pylori was revealed by bacteriology. The maximum resistance of H. pylori isolates was revealed to clarithromycin with nine resistant isolates (30.0%). The rate of resistance to metronidazole, amoxicillin, furazolidone, tetracycline, and levofloxacin was 23.3, 33.3, 16.7, 25.0, and 16.7%, respectively. Multidrug resistance was detected in 20.0% of H. pylori strains. The high prevalence of resistance to antibiotics used in eradication therapy is becoming a problem which needs eradication therapy regimen use based on regional H. pylori resistance rates

Synthesis and structure of novel phosphorylated azomethines

© 2016 Taylor & Francis Group, LLC.The condensation of do-, hexa-, octadecan-1-amines with bromo- and nitrobenzaldehydes yielded a series of Schiff bases in good yields. Subsequent reaction of these compounds with dioctylphosphine oxide yielded phosphorylated azomethines and some were characterized using X-ray crystallography. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compounds were tested for their antibacterial and anti-Candida activity. A number of the compounds exhibited antimicrobial activity comparable to that of the commercially available drugs, ciprofloxacin and clotrimazole

Chiral S-stannyl dithiophosphates and dithiophosphonates on the basis of monoterpenols

Copyright © 2018 John Wiley & Sons, Ltd. Chiral S-tributylstannyl dithiophosphates and dithiophosphonates were obtained by the reactions of optically active dithiophosphoric and dithiophosphonic acids containing (S)-(–)-menthyl and (R)-(+)-menthyl substituents with gaseous ammonia and tributyl chlorostannane. The reactions of chiral ammonium dithiophosphate containing (1R)-endo-(+)-fenchyl substituent with tributyl chlorostannane or tetrachlorostannane result in corresponding S-tributylstannyl dithiophosphate or tetrakis(dithiophosphato)stannane. Molecular structure of ammonium O,O-di-(–)-menthyldithiophosphate was studied by X-ray single crystal diffraction. Bactericidal activity of S-tributylstannyl dithiophosphates was tested

Antibiotic Susceptibility Assessment of Helicobacter pylori Isolates by Disk-Diffusion Method

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Helicobacter pylori (H. pylori) infection is tightly associated with gastrointestinal disorders such as chronic gastritis, peptic ulcer, gastric MALToma, and gastric cancer. Decreased antibiotic susceptibility in H. pylori is a worldwide problem. Our objective was to determine in vitro antimicrobial susceptibility of H. pylori isolates obtained from gastric mucosa biopsies of children with H. pylori-associated gastroduodenal diseases using disk-diffusion method. A total 76 biopsy specimens were studied; antibiotic susceptibility was assessed in case of 30 children in whom H. pylori was revealed by bacteriology. The maximum resistance of H. pylori isolates was revealed to clarithromycin with nine resistant isolates (30.0%). The rate of resistance to metronidazole, amoxicillin, furazolidone, tetracycline, and levofloxacin was 23.3, 33.3, 16.7, 25.0, and 16.7%, respectively. Multidrug resistance was detected in 20.0% of H. pylori strains. The high prevalence of resistance to antibiotics used in eradication therapy is becoming a problem which needs eradication therapy regimen use based on regional H. pylori resistance rates

The Pudovik reaction: the synthesis of bioactive α-aminophosphonates with long alkyl chains

© 2019, © 2019 Taylor & Francis Group, LLC. In this research we investigated the reactions of substituted naphthaldehyde with amines. The condensation of do-, tetra-, hexa-, octadecan-1-amines with 2-hydroxy-1-naphthaldehyde yielded a series of azomethines in good yields. Subsequent reaction of these compounds with didodecylphosphine oxide yielded α-aminophosphonates. The in vitro microbiological activity of the synthesized phosphorus compounds against gram-positive, gram-negative bacteria and the yeast Candida albicans was determined in comparison to standard agents. The synthesized compounds showed a high antibacterial and antimycotic activity against human and animal pathogenic microflora. Every newly synthesized compound was characterized by elemental analyses, IR, 1H NMR, 31P NMR spectral studies. The thermal stability was studied by synchronous thermogravimetry and differential scanning calorimetry (TG/DSC)

Synthesis and structure of novel phosphorylated azomethines

© 2016 Taylor & Francis Group, LLC.The condensation of do-, hexa-, octadecan-1-amines with bromo- and nitrobenzaldehydes yielded a series of Schiff bases in good yields. Subsequent reaction of these compounds with dioctylphosphine oxide yielded phosphorylated azomethines and some were characterized using X-ray crystallography. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compounds were tested for their antibacterial and anti-Candida activity. A number of the compounds exhibited antimicrobial activity comparable to that of the commercially available drugs, ciprofloxacin and clotrimazole

Synthesis and structure of novel phosphorylated azomethines

© 2016 Taylor & Francis Group, LLC.The condensation of do-, hexa-, octadecan-1-amines with bromo- and nitrobenzaldehydes yielded a series of Schiff bases in good yields. Subsequent reaction of these compounds with dioctylphosphine oxide yielded phosphorylated azomethines and some were characterized using X-ray crystallography. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. All of the synthesized compounds were tested for their antibacterial and anti-Candida activity. A number of the compounds exhibited antimicrobial activity comparable to that of the commercially available drugs, ciprofloxacin and clotrimazole

First Trifluoromethylated Phenanthrolinediamides: Synthesis, Structure, Stereodynamics and Complexation with Ln(III)

The first examples of 1,10-phenanthroline-2,9-diamides bearing CF3-groups on the side amide substituents were synthesized. Due to stereoisomerism and amide rotation, such complexes have complicated behavior in solutions. Using advanced NMR techniques and X-ray analysis, their structures were completely elucidated. The possibility of the formation of complex compounds with lanthanoids nitrates was shown, and the constants of their stability are quantified. The results obtained are explained in terms of quantum-chemical calculations