Objective To explore the inhibitory effects and mechanisms of benzodiazepines on Helicobacter pylori (Hp).Methods The Hp international standard strain ATCC43504 was treated with benzodiazepines diazepam,midazolam,and remimazolam,respectively.The treatments with amoxicillin and clarithromycin were taken as the positive controls,and that with water for injection as the negative control.The inhibition zone of each drug was measured by the disk diffusion method.The minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of each drug against Hp were determined.Hp suspension was configured and treated with diazepam and midazolam,respectively.The bacterial suspension without drug added was used as the control group.The concentration of K⁺ in each bacterial suspension was measured by an automatic biochemical analyzer before drug intervention(T₀)and 1(T₁),2(T₂),3(T₃),4(T₄),5(T₅),6(T₆),and 7 h(T₇)after intervention.Hp urease was extracted and treated with 1/2 MIC diazepam,1 MIC diazepam,2 MIC diazepam,1/2 MIC midazolam,1 MIC midazolam,2 MIC midazolam,1 mg/ml acetohydroxamic acid,and water for injection,respectively.The time required for the rise from pH 6.8 to pH 7.7 in each group was determined by the phenol red coloring method.Results The inhibition zones of diazepam,midazolam,remimazolam,amoxicillin,clarithromycin,and water for injection against Hp were 52.3,42.7,6.0,72.3,60.8,and 6.0 mm,respectively.Diazepam and midazolam showed the MIC of 12.5 μg/ml and 25.0 μg/ml and the MBC of 25 μg/ml and 50 μg/ml,respectively,to Hp.The concentrations of K⁺ in the diazepam,midazolam,and control groups increased during T₁-T₇ compared with those at T₀(all P<0.01).The concentration of K⁺ in diazepam and midazolam groups during T₁-T₄ was higher than that in the control group(all P<0.01).The time of inhibiting urease activity in the 1/2 MIC diazepam,1 MIC diazepam,2 MIC diazepam,1/2 MIC midazolam,1 MIC midazolam,and 2 MIC midazolam groups was(39.86±5.11),(36.52±6.65),(38.58±4.83),(39.25±6.19),(36.36±4.61),and(35.81±6.18)min,respectively,which were shorter than that in the acetohydroxamic acid group(all P<0.01)and had no significance differences from that in the water for injection group(all P>0.05).Conclusion Diazepam and midazolam exerted inhibitory effects on Hp,which may be related to the cleavage of Hp cells rather than inhibiting urease.
Midazolam ; Helicobacter pylori ; Urease ; Clarithromycin/pharmacology* ; Benzodiazepines/pharmacology* ; Diazepam/pharmacology* ; Amoxicillin ; Water ; Anti-Bacterial Agents/pharmacology*

OBJECTIVETo investigate the resistance of Helicobacter pylori (H. pylori) to antimicrobial agents in adolescents.

METHODSOne hundred and eight adolescents (6-18 years old) underwent a gastroscopy examination. H. pylori strains were isolated from gastric mucosa. Antimicrobial susceptibility testing was performed by means of Kirby-Baner.

RESULTSThirty-six H. pylori strains were identified. The resistant rate of H. pylori strains to clarithromycin, fruranzolidone and amoxicillin was 8.3%, 16.7% and 33.3%, respectively. H. pylori strains showed a high resistance to metronidazole (94.4%), while no strain was resistant to gentamicin and levofloxacin.

CONCLUSIONSThe H. pylori strains from the adolescents in Zhejiang showed a high resistance to metronidazole and amoxicillin but a low resistance to clarithromycin and fruranzolidone. All of H. pylori strains were susceptive to gentamicin and levofloxacin.

Adolescent ; Amoxicillin ; pharmacology ; Anti-Infective Agents ; pharmacology ; Child ; Clarithromycin ; pharmacology ; Drug Resistance, Bacterial ; Female ; Gastroscopy ; Helicobacter pylori ; drug effects ; Humans ; Levofloxacin ; Male ; Metronidazole ; pharmacology ; Microbial Sensitivity Tests ; Ofloxacin ; pharmacology

The standard therapy for Helicobacter pylori infection in Korea is a triple-drug regimen consisting of a proton pump inhibitor with two antibiotics such as clarithromycin, amoxicillin, and metronidazole. However, as the eradication rate of this regimen has declined over the past decade, this prompted the formulation of new therapeutic regimens. New therapeutic strategies against H. pylori infection that had been tried all over the world include sequential therapy, concomitant therapy, and tailored therapy This article will review the basic concepts and the results of previous clinical trials on the aforementioned new therapeutic regiments.
Amoxicillin/pharmacology/therapeutic use ; Anti-Bacterial Agents/pharmacology/*therapeutic use ; Clarithromycin/pharmacology/therapeutic use ; Disease Eradication/trends ; Drug Therapy, Combination ; Helicobacter Infections/*drug therapy ; *Helicobacter pylori/drug effects ; Humans ; Nitroimidazoles/pharmacology/therapeutic use ; Proton Pump Inhibitors/pharmacology/therapeutic use

Antimicrobial susceptibility testing was conducted with 6 different spirochetal strains (4 strains of Leptospira spp. and 2 strains of Borrelia burgdorferi) against 3 antimicrobial agents, commonly used in equine and bovine practice. The ranges of MIC and MBC of amoxicillin against Leptospira spp. were 0.05 - 6.25 microgram/ml and 6.25 - 25.0 microgram/ml, respectively. And the ranges of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of amoxicillin against B. burgdorferi were 0.05 - 0.39 microgram/ml and 0.20 - 0.78 microgram/ml, respectively. The ranges of MIC and MBC of enrofloxacin against Leptospira spp. were 0.05 - 0.39 microgram/ml and 0.05 - 0.39 microgram/ml, respectively. Two strains of B. burgdorferi were resistant to enrofloxacin at the highest concentration tested for MBC (> or = 100 microgram/ml). Therefore, the potential role of tilmicosin in the treatment of leptospirosis and borreliosis should be further evaluated in animal models to understand whether the in vivo studies will confirm in vitro results. All spirochetal isolates were inhibited (MIC) and were killed (MBC) by tilmicosin at concentrations below the limit of testing (< or = 0.01 microgram/ml).
Amoxicillin/pharmacology ; Anti-Bacterial Agents/*pharmacology ; Borrelia burgdorferi/*drug effects/growth & development/isolation & purification ; Fluoroquinolones/pharmacology ; Leptospira/*drug effects/growth & development/isolation & purification ; Leptospirosis/*microbiology ; Lyme Disease/*microbiology ; Macrolides/pharmacology ; Microbial Sensitivity Tests ; Reproducibility of Results ; Tylosin/analogs & derivatives/pharmacology

OBJECTIVETo investigate the prevalence of Helicobacter pylori (Hp) resistant to clarithromycin, amoxicillin and metronidazole in children.

METHODSA total of 44 Hp clinical isolates were cultured from children patients with Hp gastritis and peptic ulcer who underwent gastroscopy during the period from October 2002 to November 2003 in Children's Hospital affiliated to Medical College of Zhejiang University. Nineteen of the patients were girls and 25 boys. The mean age was 8.66 +/- 2.66 years (3 approximately 14 years). The susceptibilities of the 44 Hp strains to clarithromycin, amoxicillin and metronidazole were tested by agar dilution test to determine minimum inhibitory concentration (MIC)(50), MIC(90) and resistance rates were also calculated.

RESULTSAmong the 44 Hp strains isolated from children, 8, 4, and 14 strains were resistant to clarithromycin, amoxicillin and metronidazole and the resistant rate was 18.2% (8/44), 9.1% (4/44) and 31.8% (14/44), with MICs for all strains ranging from < 0.125 microg/ml to 64 microg/ml, < 0.125 microg/ml to 64 microg/ml and < 0.125 microg/ml to 128 microg/ml, respectively. MIC(50) and MIC(90) of clarithromycin, amoxicillin and metronidazole were < 0.125 microg/ml, 8 microg/ml; < 0.125 microg/ml, 0.5 microg/ml; 0.5 microg/ml, 128 microg/ml, respectively. The prevalence of Hp resistant to clarithromycin was higher in children than that in adults, while to metronidazole was lower than that in adults with high MICs (32 - 128 microg/ml) and MIC(90) (128 microg/ml) of metronidazole for resistant isolates. Three multidrug resistant strains (6.8%) were simultaneously resistant to these three antibiotics.

CONCLUSIONSThe prevalence of Helicobacter pylori resistant to metronidazole was high in children, and the rate of resistance to clarithromycin was higher than that isolated from adults. Amoxicillin-resistant strains were now found, and multidrug resistant strains which resistant to the three antibiotics also emerged.

Adolescent ; Amoxicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Child ; Child, Preschool ; Clarithromycin ; pharmacology ; Drug Resistance, Multiple, Bacterial ; Female ; Gastritis ; microbiology ; Gastroscopy ; Helicobacter pylori ; drug effects ; isolation & purification ; Humans ; Male ; Metronidazole ; pharmacology ; Microbial Sensitivity Tests ; Peptic Ulcer ; microbiology ; Prevalence

Bismuth-containing quadruple therapy (BQT) has long been recommended for Helicobacter pylori ( H. pylori ) eradication in China. Meanwhile, in the latest national consensus in China, dual therapy (DT) comprising an acid suppressor and amoxicillin has also been recommended. In recent years, the eradication rate of H. pylori has reached >90% using DT, which has been used not only as a first-line treatment but also as a rescue treatment. Compared with BQT, DT has great potential for H. pylori eradication; however, it has some limitations. This review summarizes the development of DT and its application in H. pylori eradication. The H. pylori eradication rates of DT were comparable to or even higher than those of BQT or standard triple therapy, especially in the first-line treatment. The incidence of adverse events associated with DT was lower than that with other therapies. Furthermore, there were no significant differences in the effects of dual and quadruple therapies on gastrointestinal microecology. In the short term, H. pylori eradication causes certain fluctuations in the gastrointestinal microbiota; however, in the long term, the gastrointestinal microbiota eventually returns to its normal state. In the penicillin-naïve population, patients receiving DT have a high eradiation rate, better compliance, lower incidence of adverse reactions, and lower primary and secondary resistance to amoxicillin. These findings suggest the safety, efficacy, and potential of DT for H. pylori eradication.
Humans ; Helicobacter Infections/drug therapy* ; Anti-Bacterial Agents/pharmacology* ; Helicobacter pylori ; Proton Pump Inhibitors ; Drug Therapy, Combination ; Amoxicillin/therapeutic use* ; Treatment Outcome

BACKGROUND/AIMS: This study was performed to compare the prevalence rates of primary antibiotic resistance in Helicobacter pylori (H. pylori) isolates among different regions of Korea. METHODS: H. pylori were isolated from gastric mucosal biopsy specimens of 99 Koreans who lived in Gyeonggi (n=40), Kangwon province (n=40) and Busan (n=19) from April to August in 2008. All the patients had no history of H. pylori eradication therapy. The susceptibilities of the H. pylori isolates to amoxicillin, clarithromycin, metronidazole, tetracycline, azithromycin, ciprofloxacin, levofloxacin, and moxifloxacin were tested according to the agar dilution method. RESULTS: There was a difference in resistance to clarithromycin in three institutes located among Gyeonggi (32.5%), Kangwon province (12.5%) and Busan (42.1%) by One way ANOVA test (p=0.027) and nonparametric Kruskal Wallis test (p=0.027). However, by post-hoc analysis, there was no statistically significant difference among three regions. Similarly, the other 7 antibiotics (amoxicillin, metronidazole, tetracycline, azithromycin, ciprofloxacin, levofloxacin and moxifloxacin) did not show any significant difference. CONCLUSIONS: There was no significant regional difference of the primary antibiotic resistance of H. pylori. However, the included patient number might not be enough for this conclusion demanding further evaluations.
Amoxicillin/pharmacology ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Aza Compounds/pharmacology ; Azithromycin/pharmacology ; Ciprofloxacin/pharmacology ; Clarithromycin/pharmacology ; *Drug Resistance, Bacterial ; Female ; Helicobacter Infections/*epidemiology/microbiology ; Helicobacter pylori/*drug effects/isolation & purification ; Humans ; Male ; Metronidazole/pharmacology ; Microbial Sensitivity Tests ; Middle Aged ; Ofloxacin/pharmacology ; Quinolines/pharmacology ; Republic of Korea/epidemiology ; Tetracycline/pharmacology

BACKGROUND/AIMS: This study was performed to compare the prevalence rates of primary antibiotic resistance in Helicobacter pylori (H. pylori) isolates among different regions of Korea. METHODS: H. pylori were isolated from gastric mucosal biopsy specimens of 99 Koreans who lived in Gyeonggi (n=40), Kangwon province (n=40) and Busan (n=19) from April to August in 2008. All the patients had no history of H. pylori eradication therapy. The susceptibilities of the H. pylori isolates to amoxicillin, clarithromycin, metronidazole, tetracycline, azithromycin, ciprofloxacin, levofloxacin, and moxifloxacin were tested according to the agar dilution method. RESULTS: There was a difference in resistance to clarithromycin in three institutes located among Gyeonggi (32.5%), Kangwon province (12.5%) and Busan (42.1%) by One way ANOVA test (p=0.027) and nonparametric Kruskal Wallis test (p=0.027). However, by post-hoc analysis, there was no statistically significant difference among three regions. Similarly, the other 7 antibiotics (amoxicillin, metronidazole, tetracycline, azithromycin, ciprofloxacin, levofloxacin and moxifloxacin) did not show any significant difference. CONCLUSIONS: There was no significant regional difference of the primary antibiotic resistance of H. pylori. However, the included patient number might not be enough for this conclusion demanding further evaluations.
Amoxicillin/pharmacology ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Aza Compounds/pharmacology ; Azithromycin/pharmacology ; Ciprofloxacin/pharmacology ; Clarithromycin/pharmacology ; *Drug Resistance, Bacterial ; Female ; Helicobacter Infections/*epidemiology/microbiology ; Helicobacter pylori/*drug effects/isolation & purification ; Humans ; Male ; Metronidazole/pharmacology ; Microbial Sensitivity Tests ; Middle Aged ; Ofloxacin/pharmacology ; Quinolines/pharmacology ; Republic of Korea/epidemiology ; Tetracycline/pharmacology

OBJECTIVETo investigate the relationship between point mutation of penicillin-binding protein gene (pbp) and amoxicillin resistance (AMOgamma) of Helicobacter pylori (H. pylori) as well as to compare the protein profiles under proteomic technology to get the candidate resistance-related proteins.

METHODS(1) AMOgamma strains were selected from the sensitive H. pylori strain 26695 by serial passage technique in vitro. (2) Point mutations of five putative resistance genes (HP0597, HP1565, HP1542, HP1556, and HP0160) were analyzed by denaturing high-performance liquid chromatography (DHPLC) and DNA sequencing. (3) Proteins samples were separated by two-dimensional electrophoresis (2-DE). Protein profiles were compared between the AMOgamma strain obtained in vitro and its sensitive parent strain 26695. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was performed to identify the proteins of interest. The proteins were searched by software MASCOT and identified by peptide fingerprint map using the program MS-FIT of Protein Prospect.

RESULTS(1) An AMOgamma strain (MIC 8 microg/ml) was obtained. Complete loss of the resistant phenotype was observed after cultivation in the absence of AMO or storage at - 80 degrees C. (2) DHPLC and Sequencing result showed no point mutations in five pbp genes in the AMOgamma strain when compared with the corresponding PCR products from its parent strain 26695. (3) Protein profiling showed that eleven protein spots were differently expressed between 26695 and the AMOgamma strain. Of these protein spots in the AMOgamma strain, two new spots (Spot 1 and Spot 2) were observed with one (Spot 3) was up-regulated three-fold and the remained ones (Spot 4-11) were down-regulated.

CONCLUSIONAMO resistance of H. pylori might be resulted from, unstable phenotype change rather than point mutations of pbp genes. These differentially regulated proteins in AMOgamma strain might play a role in development of resistance to AMO in H. pylori.

Amoxicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Chromatography, High Pressure Liquid ; Drug Resistance, Bacterial ; genetics ; Electrophoresis, Gel, Two-Dimensional ; Helicobacter pylori ; drug effects ; genetics ; metabolism ; Point Mutation ; genetics ; physiology ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

BACKGROUND: Given the general unavailability, common adverse effects, and complicated administration of tetracycline, the clinical application of classic bismuth quadruple therapy (BQT) is greatly limited. Whether minocycline can replace tetracycline for Helicobacter pylori ( H . pylori ) eradication is unknown. We aimed to compare the eradication rate, safety, and compliance between minocycline- and tetracycline-containing BQT as first-line regimens. METHODS: This randomized controlled trial was conducted on 434 naïve patients with H . pylori infection. The participants were randomly assigned to 14-day minocycline-containing BQT group (bismuth potassium citrate 110 mg q.i.d., esomeprazole 20 mg b.i.d., metronidazole 400 mg q.i.d., and minocycline 100 mg b.i.d.) and tetracycline-containing BQT group (bismuth potassium citrate/esomeprazole/metronidazole with doses same as above and tetracycline 500 mg q.i.d.). Safety and compliance were assessed within 3 days after eradication. Urea breath test was performed at 4-8 weeks after eradication to evaluate outcome. We used a noninferiority test to compare the eradication rates of the two groups. The intergroup differences were evaluated using Pearson chi-squared or Fisher's exact test for categorical variables and Student's t -test for continuous variables. RESULTS: As for the eradication rates of minocycline- and tetracycline-containing BQT, the results of both intention-to-treat (ITT) and per-protocol (PP) analyses showed that the difference rate of lower limit of 95% confidence interval (CI) was >-10.0% (ITT analysis: 181/217 [83.4%] vs . 180/217 [82.9%], with a rate difference of 0.5% [-6.9% to 7.9%]; PP analysis: 177/193 [91.7%] vs . 176/191 [92.1%], with a rate difference of -0.4% [-5.6% to 6.4%]). Except for dizziness more common (35/215 [16.3%] vs . 13/214 [6.1%], P = 0.001) in minocycline-containing therapy groups, the incidences of adverse events (75/215 [34.9%] vs . 88/214 [41.1%]) and compliance (195/215 [90.7%] vs . 192/214 [89.7%]) were similar between the two groups. CONCLUSION: The eradication efficacy of minocycline-containing BQT was noninferior to tetracycline-containing BQT as first-line regimen for H . pylori eradication with similar safety and compliance. TRIAL REGISTRATION ClinicalTrials.gov, ChiCTR 1900023646.
Humans ; Bismuth/therapeutic use* ; Metronidazole/therapeutic use* ; Esomeprazole/pharmacology* ; Minocycline/pharmacology* ; Helicobacter pylori ; Potassium Citrate/therapeutic use* ; Anti-Bacterial Agents ; Tetracycline/adverse effects* ; Helicobacter Infections/drug therapy* ; Drug Therapy, Combination ; Amoxicillin