In-vitro characterisation of a novel antimicrobial agent, TNP-2092, against Helicobacter pylori clinical isolates

The essential oil of the dried aerial parts of Thymus caramanicus at full flowering stage was prepared by hydrodistillation with a yield of 2.5% oil. The oil analysis by a combination of capillary GC and GC-MS revealed 26 components of which carvacrol (68.9%) was the main component, followed by p-cymene (6.0%), thymol (5.3%), γ-terpinene (4.6%) and borneol (4.0%) representing 98.9% of the total oil. The in vitro antibacterial activity of the essential oil was determined against ten clinical isolates of Helicobacter pylori using disc diffusion, as well as measurement of minimum inhibitory concentrations. The results showed high inhibitory activity against all test bacteria by the disc diffusion method (zones of inhibition of 50.0 – 65.0 mm). Minimum inhibitory concentration values were within the range 14.5 – 58.0 μg/mL for the clinical isolates.

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M1067 In Vitro Activityies of Levofloxacin and Seven Other Fluorquinolones Against Clinical Isolates of Helicobacter pylori with or Without gYRA Mutations; What Regimen Is a Promising Eradication Therapy in the Next Generation?

Gastroenterology ◽

10.1016/s0016-5085(08)61543-7 ◽

2008 ◽

Vol 134 (4) ◽

pp. A-331

Author(s):

Hideyuki Miyachi ◽

Ikuya Miki ◽

Daisuke Shirasaka ◽

Yuko Matsumoto ◽

Shigeto Mizuno ◽

...

Keyword(s):

Helicobacter Pylori ◽

Eradication Therapy ◽

Clinical Isolates ◽

Next Generation

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In Vitro and In Vivo Antibacterial Activities of Patchouli Alcohol, a Naturally Occurring Tricyclic Sesquiterpene, against Helicobacter pylori Infection

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00122-17 ◽

2017 ◽

Vol 61 (6) ◽

Cited By ~ 16

Author(s):

Y. F. Xu ◽

D. W. Lian ◽

Y. Q. Chen ◽

Y. F. Cai ◽

Y. F. Zheng ◽

...

Keyword(s):

Helicobacter Pylori ◽

Bacterial Resistance ◽

Clinical Isolates ◽

Potential Candidate ◽

Necrosis Factor Alpha ◽

Content Type ◽

Patchouli Alcohol ◽

H Pylori

ABSTRACT This study further evaluated the in vitro and in vivo anti-Helicobacter pylori activities and potential underlying mechanism of patchouli alcohol (PA), a tricyclic sesquiterpene. In the in vitro assay, the capacities of PA to inhibit and kill H. pylori were tested on three standard strains at different pH values and on 12 clinical isolates. The effects of PA on H. pylori adhesion (and its alpA, alpB, and babA genes), motility (and its flaA and flaB genes), ultrastructure, and flagellation were investigated. Moreover, the H. pylori resistance to and postantibiotic effect (PAE) of PA were determined. Furthermore, the in vivo effects of PA on H. pylori eradication and gastritis were examined. Results showed that MICs of PA against three standard strains (pH 5.3 to 9) and 12 clinical isolates were 25 to 75 and 12.5 to 50 μg/ml, respectively. The killing kinetics of PA were time and concentration dependent, and its minimal bactericidal concentrations (MBCs) were 25 to 75 μg/ml. In addition, H. pylori adhesion, motility, ultrastructure, and flagellation were significantly suppressed. PA also remarkably inhibited the expression of adhesion genes (alpA and alpB) and motility genes (flaA and flaB). Furthermore, PA treatment caused a longer PAE and less bacterial resistance than clarithromycin and metronidazole. The in vivo study showed that PA can effectively eradicate H. pylori, inhibit gastritis, and suppress the expression of inflammatory mediators (COX-2, interleukin 1β, tumor necrosis factor alpha, and inducible nitric oxide synthase [iNOS]). In conclusion, PA can efficiently kill H. pylori, interfere with its infection process, and attenuate gastritis with less bacterial resistance, making it a potential candidate for new drug development.

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Variations in Helicobacter pylori Lipopolysaccharide To Evade the Innate Immune Component Surfactant Protein D

Infection and Immunity ◽

10.1128/iai.73.11.7677-7686.2005 ◽

2005 ◽

Vol 73 (11) ◽

pp. 7677-7686 ◽

Cited By ~ 38

Author(s):

Wafa Khamri ◽

Anthony P. Moran ◽

Mulugeta L. Worku ◽

Q. Najma Karim ◽

Marjorie M. Walker ◽

...

Keyword(s):

Helicobacter Pylori ◽

Gastric Mucosa ◽

Phase Variation ◽

Surfactant Protein ◽

Clinical Isolates ◽

Surfactant Protein D ◽

Human Gastric Mucosa ◽

H Pylori

ABSTRACT Helicobacter pylori is a common and persistent human pathogen of the gastric mucosa. Surfactant protein D (SP-D), a component of innate immunity, is expressed in the human gastric mucosa and is capable of aggregating H. pylori. Wide variation in the SP-D binding affinity to H. pylori has been observed in clinical isolates and laboratory-adapted strains. The aim of this study was to reveal potential mechanisms responsible for evading SP-D binding and establishing persistent infection. An escape variant, J178V, was generated in vitro, and the lipopolysaccharide (LPS) structure of the variant was compared to that of the parental strain, J178. The genetic basis for structural variation was explored by sequencing LPS biosynthesis genes. SP-D binding to clinical isolates was demonstrated by fluorescence-activated cell sorter analyses. Here, we show that H. pylori evades SP-D binding through phase variation in lipopolysaccharide. This phenomenon is linked to changes in the fucosylation of the O chain, which was concomitant with slipped-strand mispairing in a poly(C) tract of the fucosyltransferase A (fucT1) gene. SP-D binding organisms are predominant in mucus in vivo (P = 0.02), suggesting that SP-D facilitates physical elimination. Phase variation to evade SP-D contributes to the persistence of this common gastric pathogen.

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In – Vitro activity of Desmostachya bipinnata (L.) Stapf successive extracts against Helicobacter pylori clinical isolates

Saudi Pharmaceutical Journal ◽

10.1016/j.jsps.2018.02.002 ◽

2018 ◽

Vol 26 (4) ◽

pp. 535-540 ◽

Cited By ~ 4

Author(s):

Nermin H. Ibrahim ◽

Amani S. Awaad ◽

Rawan A. Alnafisah ◽

Saleh I. Alqasoumi ◽

Reham.M. El-Meligy ◽

...

Keyword(s):

Helicobacter Pylori ◽

Vitro Activity ◽

Clinical Isolates ◽

In Vitro Activity

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In Vitro Activities of Rabeprazole, a Novel Proton Pump Inhibitor, and Its Thioether Derivative Alone and in Combination with Other Antimicrobials against Recent Clinical Isolates ofHelicobacter pylori

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.2.458-461.2000 ◽

2000 ◽

Vol 44 (2) ◽

pp. 458-461 ◽

Cited By ~ 33

Author(s):

Yoshiyuki Kawakami ◽

Takayuki Akahane ◽

Masaru Yamaguchi ◽

Kozue Oana ◽

Yuko Takahashi ◽

...

Keyword(s):

Helicobacter Pylori ◽

Proton Pump Inhibitor ◽

Proton Pump ◽

Synergistic Effects ◽

Antagonistic Effect ◽

Clinical Isolates ◽

Rabeprazole Sodium ◽

Kill Curve ◽

Time Kill

ABSTRACT The MICs of rabeprazole sodium (RPZ), a newly developed benzimidazole proton pump inhibitor (PPI), against 133 clinicalHelicobacter pylori strains revealed a higher degree of activity than the another two PPIs, lansoprazole and omeprazole. Time-kill curve assays of RPZ, when combined with amoxicillin, clarithromycin, or metronidazole, disclosed that synergistic effects were demonstrated in combination with each antibiotic examined. Moreover, no apparent antagonistic effect appeared among all of the strains tested.

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In Vitro and In Vivo Inhibition of Helicobacter pylori by Lactobacillus casei Strain Shirota

Applied and Environmental Microbiology ◽

10.1128/aem.70.1.518-526.2004 ◽

2004 ◽

Vol 70 (1) ◽

pp. 518-526 ◽

Cited By ~ 188

Author(s):

D. Sgouras ◽

P. Maragkoudakis ◽

K. Petraki ◽

B. Martinez-Gonzalez ◽

E. Eriotou ◽

...

Keyword(s):

Helicobacter Pylori ◽

Lactobacillus Casei ◽

Clinical Isolates ◽

Mucosal Inflammation ◽

Control Group ◽

Study Group ◽

Milk Product ◽

H Pylori

ABSTRACT We studied the potential inhibitory effect of Lactobacillus casei strain Shirota (from the fermented milk product Yakult [Yakult Ltd., Tokyo, Japan]) on Helicobacter pylori by using (i) in vitro inhibition assays with H. pylori SS1 (Sydney strain 1) and nine H. pylori clinical isolates and (ii) the in vivo H. pylori SS1 mouse model of infection over a period of 9 months. In vitro activity against H. pylori SS1 and all of the clinical isolates was observed in the presence of viable L. casei strain Shirota cells but not in the cell-free culture supernatant, although there was profound inhibition of urease activity. In vivo experiments were performed by oral administration of L. casei strain Shirota in the water supply over a period of 9 months to 6-week-old C57BL/6 mice previously infected with H. pylori SS1 (study group; n = 25). Appropriate control groups of H. pylori-infected but untreated animals (n = 25) and uninfected animals given L. casei strain Shirota (n = 25) also were included in the study. H. pylori colonization and development of gastritis were assessed at 1, 2, 3, 6, and 9 months postinfection. A significant reduction in the levels of H. pylori colonization was observed in the antrum and body mucosa in vivo in the lactobacillus-treated study group, as assessed by viable cultures, compared to the levels in the H. pylori-infected control group. This reduction was accompanied by a significant decline in the associated chronic and active gastric mucosal inflammation observed at each time point throughout the observation period. A trend toward a decrease in the anti-H. pylori immunoglobulin G response was measured in the serum of the animals treated with lactobacillus, although this decrease was not significant.

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