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*

A series of 119 Mycobacterium avium complex isolates were subjected to clarithromycin susceptibility testing using microplates containing 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC). Among 119 isolates, 114 (95.8%) were susceptible to clarithromycin and 5 were resistant according to the new and the standard method. STC counts the low cost and reduces the number of procedures needed for susceptibility testing.
Clarithromycin/*pharmacology ; Culture Media ; Humans ; Microbial Sensitivity Tests/*methods ; Mycobacterium avium Complex/*drug effects/isolation & purification ; Tetrazolium Salts/*chemistry

A series of 119 Mycobacterium avium complex isolates were subjected to clarithromycin susceptibility testing using microplates containing 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC). Among 119 isolates, 114 (95.8%) were susceptible to clarithromycin and 5 were resistant according to the new and the standard method. STC counts the low cost and reduces the number of procedures needed for susceptibility testing.
Clarithromycin/*pharmacology ; Culture Media ; Humans ; Microbial Sensitivity Tests/*methods ; Mycobacterium avium Complex/*drug effects/isolation & purification ; Tetrazolium Salts/*chemistry

BACKGROUND: Antimicrobial susceptibility of Legionella spp. has rarely been studied in Korea. Therefore, we aimed to determine the susceptibility of Legionella spp. to various antibiotics. METHODS: We assessed the antimicrobial susceptibility of 66 environmental and clinical Legionella isolates collected between January 2001 and December 2008 from Korea and Japan. The minimum inhibitory concentrations (MICs) of 6 antibiotics, namely, azithromycin, ciprofloxacin, clarithromycin, clindamycin, gatifloxacin, and gemifloxacin were determined by the broth microdilution method using buffered starch yeast extract broth. RESULTS: The MIC ranges of the 6 antibiotics used against the Legionella isolates were as follows: 0.004-0.062 microgram/mL (azithromycin), 0.002-0.5 microgram/mL (ciprofloxacin), 0.004-0.5 microgram/mL (clarithromycin), 0.12-4 microgram/mL (clindamycin), 0.002-0.12 microgram/mL (gatifloxacin), and 0.008-1 microgram/mL (gemifloxacin). CONCLUSIONS: Legionella spp. isolates from Korea and Japan were most susceptible to gatifloxacin. Azithromycin, clarithromycin, ciprofloxacin, and gemifloxacin were also effective for treating legionellosis.
Anti-Bacterial Agents/*pharmacology ; Azithromycin/pharmacology ; Ciprofloxacin/pharmacology ; Clarithromycin/pharmacology ; Clindamycin/pharmacology ; Drug Resistance, Bacterial ; Fluoroquinolones/pharmacology ; Humans ; Legionella/*drug effects/isolation & purification ; Legionellosis/diagnosis/microbiology ; Microbial Sensitivity Tests ; Naphthyridines/pharmacology

BACKGROUNDMycobacterium abscessus (M. abscessus) can cause a variety of human infections, involving the lung, skin and soft tissues, and is generally believed to be acquired from environmental sources. The aim of this study was to investigate the molecular diversity and antibiotic susceptibility of M. abscessus isolates as the basis for strategies to improve control and management of infection.

METHODSSeventy M. abscessus isolates from patients attending the Guangzhou Thoracic Hospital were identified from 2003 to 2005 by biochemical tests, gas chromatography, polymerase chain reaction (PCR)-restriction analysis (PRA) of heat shock protein gene hsp65, and sequencing of the quinolone resistance determining regions (QRDRs) of gyrA. Susceptibilities to six antibiotics were determined by micro-broth dilution. Isolates were genotyped using randomly amplified polymorphic DNA (RAPD) analysis.

RESULTSMost isolates (63/70; 90%) were susceptible to amikacin but rates of susceptibility to other antibiotics varied from moderate, clarithromycin (60%) and imipenem (43%), to low for ciprofloxacin and ofloxacin (3%), and 87% of isolates had intermediate susceptibility to cefoxitin. RAPD analysis showed that the 70 clinical isolates displayed 69 unique RAPD patterns.

CONCLUSIONSThe high genetic diversity of isolates suggests that they are not transmitted from person to person but, presumably, are acquired independently from environmental sources. M. abscessus isolates displayed variable levels of susceptibility to all antibiotics tested, other than amikacin, indicating a need for routine susceptibility testing to guide treatment.

Amikacin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Cefoxitin ; pharmacology ; China ; Chromatography, Gas ; Ciprofloxacin ; pharmacology ; Clarithromycin ; pharmacology ; Imipenem ; pharmacology ; Microbial Sensitivity Tests ; Mycobacterium ; drug effects ; genetics ; Polymerase Chain Reaction ; Random Amplified Polymorphic DNA Technique

As the incidence of nontuberculous mycobacterial infection has been increasing recently in Korea, the importance of drug susceptibility test for clinical isolates of mycobacteria has become larger. In this study we determined the antimicrobial susceptibility patterns of clinical isolates of M. fortuitum and M. abscessus in Korea, and evaluated the efficacy of a modified broth microdilution method using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC), in terms of its ability to provide accurate and easy-to-read minimal inhibitory concentration (MIC) endpoints for the susceptibility testing of rapidly growing mycobacteria. Most isolates of M. fortuitum and M. abscessus in Korea are susceptible or intermediately susceptible to amikacin, cefoxitin, ciprofloxacin, and clarithromycin. Many isolates of M. fortuitum are susceptible to doxycycline, sulfamethoxazole, and imipenem, while many M. abscessus isolates are resistant to these drugs. In the present study, the modified broth microdilution method using STC was found to be reliable, easy to read, and inexpensive for M. fortuitum and M. abscessus susceptibility testing. The modified colorimetric MIC testing method using STC was proven to be a useful surrogate for RGM antibiotic susceptibility testing.
Anti-Bacterial Agents/pharmacology ; Cefoxitin/pharmacology ; Chemistry, Pharmaceutical/methods ; Ciprofloxacin/pharmacology ; Clarithromycin/pharmacology ; Colorimetry/methods ; Drug Resistance, Bacterial ; Korea ; *Microbial Sensitivity Tests ; Mycobacterium/*metabolism ; Mycobacterium fortuitum/*metabolism ; Tetrazolium Salts/*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

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

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

OBJECTIVE: To investigate the expression of vascular endothelial growth factor in the nasal mucosa of chronic rhinosinusitis with nasal polys patients, and explored the regulation of clarithromycin on VEGF. METHOD: RT-PCR was used to detect the expression of VEGF in nasal mucosa from healthy control and CRSwNP. Nasal mucosal tissue explant culture measure and ELISA were used to explore the effect of clarithromycin on VEGF expression. RESULT: (1) VEGF mRNA expression level was significantly increased in CRSwNP compared with control and showed a statistic difference (P < 0.01). (2) There was a significant decrease in CRSwNP group undergo clarithromycin treatment on protein expression level of VEGF and showed a statistic difference (P < 0.05). CONCLUSION VEGF were overexpressed in CRSwNP group, which presume that play an important role in the pathogenesis of nasal polyps. Clarithromycin may play a therapeutical role on chronic rhinosinusitis through down-regulated the expression of VEGF.
Adult ; Chronic Disease ; Clarithromycin ; pharmacology ; Female ; Humans ; Male ; Nasal Mucosa ; metabolism ; Nasal Polyps ; complications ; Rhinitis ; complications ; metabolism ; Sinusitis ; complications ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism ; Young Adult