INTRODUCTIONEradication of Helicobacter pylori,a bacteriumresiding in stomach and causing peptic ulcer disease,can be achieved by using combination therapiesconsisting of one or two antibiotics with a protonpump inhib...INTRODUCTIONEradication of Helicobacter pylori,a bacteriumresiding in stomach and causing peptic ulcer disease,can be achieved by using combination therapiesconsisting of one or two antibiotics with a protonpump inhibitor (PPI).The major antibiotics widelyused in the regimens to eradicate H.pylori aremetronidazole and clarithromycin.However,resistance to these antibiotics by H.pylori展开更多
An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has be...An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis.展开更多
AIM:To characterise the cag pathogenicity island in Helicobacter pylori(H.pylori) isolates by analysing the strains' vacA alleles and metronidazole susceptibilities in light of patient ethnicity and clinical outco...AIM:To characterise the cag pathogenicity island in Helicobacter pylori(H.pylori) isolates by analysing the strains' vacA alleles and metronidazole susceptibilities in light of patient ethnicity and clinical outcome.METHODS:Ninety-five H.pylori clinical isolates obtained from patients with dyspepsia living in Malaysia were analysed in this study.Six genes in the cagPAI region(cagE,cagM,cagT,cag13,cag10 and cag67) andvacA alleles of theH.pylori isolates were identified by polymerase chain reaction.The isolates' metronidazole susceptibility was also determined using the E-test method,and the resistant gene was characterised by sequencing.RESULTS:More than 90% of the tested isolates had at least one gene in the cagPAI region,and cag67 was predominantly detected in the strains isolated from the Chinese patients,compared with the Malay and Indian patients(P < 0.0001).The majority of the isolates(88%) exhibited partial deletion(rearrangement) in the cagPAI region,with nineteen different patterns observed.Strains with intact or deleted cagPAI regions were detected in 3.2% and 8.4% of isolates,respectively.The prevalence of vacA s1m1 was significantly higher in the Malay and Indian isolates,whereas the isolates from the Chinese patients were predominantly genotyped as vacA s1m2(P = 0.018).Additionally,the isolates from the Chinese patients were more sensitive to metronidazole than the isolates from the Malay and Indian patients(P = 0.047).Although we attempted to relate the cagPAI genotypes,vacA alleles and metronidazole susceptibilities to disease outcome,no association was observed.The vacA alleles were distributed evenly among the strains with intact,partially deleted or deleted cagPAI regions.Interestingly,the strains exhibiting an intact cagPAI region were sensitive to metronidazole,whereas the strains with a deleted cagPAI were more resistant.CONCLUSION:Successful colonisation by different H.pylori genotypes is dependent on the host's genetic makeup and may play an important role in the clinical outcome.展开更多
Monitoring the concentration of antibiotics in body fluids is essential to optimizing the therapy and minimizing the risk of bacteria resistance,which can be made with electrochemical sensors tailored with appropriate...Monitoring the concentration of antibiotics in body fluids is essential to optimizing the therapy and minimizing the risk of bacteria resistance,which can be made with electrochemical sensors tailored with appropriate materials.In this paper,we report on sensors made with screen-printed electrodes(SPE)coated with fullerene(C60),reduced graphene oxide(rGO)and Nafion(NF)(C60-rGO-NF/SPE)to determine the antibiotic metronidazole(MTZ).Under optimized conditions,the C60-rGO-NF/SPE sensor exhibited a linear response in square wave voltammetry for MTZ concentrations from 2.5×10^(-7) to 34×10^(-6) mol/L,with a detection limit of 2.1×10^(-7) mol/L.This sensor was also capable of detecting MTZ in serum and urine,with recovery between 94%and 100%,which are similar to those of the standard chromatographic method(HPLC-UV).Because the C60-rGO-NF/SPE sensor is amenable to mass production and allows for MTZ determination with simple principles of detection,it fulfills the requirements of therapeutic drug monitoring programs.展开更多
Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward...Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this issue.In this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was evaluated.Major intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed herein.This plasma-catalytic process has bright prospects in the field of antibiotics degradation.展开更多
Objective:To identify the frequencies(F) of ferredoxin and nitroreductase mutations were identified on Iranian clinical isolates of Giardia lamblia in order to predict whether the nitazoxanide can be prescribed as sui...Objective:To identify the frequencies(F) of ferredoxin and nitroreductase mutations were identified on Iranian clinical isolates of Giardia lamblia in order to predict whether the nitazoxanide can be prescribed as suitable drug for symptomatic to metronidazoleresistant giardiasis.Methods:Forty Giardia lamblia isolates as of 38 symptomatic and two metronidazole-resistant patients were collected from Iran.DNAs were extracted and amplified by targeting ferredoxin and Gl NR genes.The amplicons were directly sequenced to determine gene mutations.Results:The various amino acid substitutions(F:20%,Haplotype diversity:0.891,Tajima's D:-0.44013) were identified by analyzing ferredoxin gene in four symptomatic and two resistant isolates.Only,two haplotypes(F:5%,HD:0.345; Tajima's D:0.77815) characterized in metronidazole-resistant isolates of Gl NR,however,no point mutations was found in symptomatic isolates.Conclusions:Non-synonymous mutations of ferredoxin oxidoreductase gene reduce translational regulatory protein's binding affinity which concludes reduction of ferredoxin expression and its activity.This leads to decrease in metronidazole drug delivery into the cells.Mutations in these isolates may lead to their resistance to metronidazole.No to low synonymous mutations of Gl NR demonstrates that nitazoxanide can be prescribed as promising alternative treatment for symptomatic to metronidazole-resistant giardiasis in Iranian clinical isolates.展开更多
Objective:To compare effect of Hypericum perforatum(H.perforatum) vaginal gel with metronidazole on bacterial vaginosis(BV) in terms of initial response to treatment and preventing recurrence(primary outcomes) and als...Objective:To compare effect of Hypericum perforatum(H.perforatum) vaginal gel with metronidazole on bacterial vaginosis(BV) in terms of initial response to treatment and preventing recurrence(primary outcomes) and also patient complaints(secondary outcomes).Methods:In this double-blind,double dummy trial,married women aged 18-49 with BV were randomized into two groups and administered 5 g of 3%H.perforatum and placebo of metronidazole(n=82),or 5 g of 0.75%metronidazole and placebo of H.peiforatum(n=80)vaginally for 5 d.Amsel criteria were used for diagnosis and assessing cure and recurrence of BV.The comparisons was done using Chi-square,Fisher's exact and logistic regression.Results:At 10-12 d.cure rate was 82%in the H.perforatum and 85%in metronidazole group(risk ratio 0.9.95%confidence interval 0.6 to 1.3).Among the cured women,recurrence rate was 9%in the H.perforatum and 13%in the metronidazole group at the 30-35 d visit(risk ratio 0.8,95%confidence interval 0.4 to 1.3),There was no statistically significant difference between the groups regarding any patient complaints,except itching which was less in H.perforatum group(5%vs.16%,P=0.018 at the first and 13%vs.43%,P<0.001 at the second follow-up).No significant adverse event was reported at any groups.Conclusions:H.peiforatum could be a good option for treatment of BV.However,further studies arc needed for its public use.展开更多
Aim: To investigate the efficacy and tolerability of second-line metronidazole triple therapy with vonoprazan (VPZ) for Helicobacter pylori (H. pylori). Methods: We retrospectively reviewed medical records of patients...Aim: To investigate the efficacy and tolerability of second-line metronidazole triple therapy with vonoprazan (VPZ) for Helicobacter pylori (H. pylori). Methods: We retrospectively reviewed medical records of patients who experienced clarithromycin triple therapy failure and were treated with second-line (20 mg VPZ (n = 274)/30 mg lansoprazole (n = 323) or 10 mg rabeprazole (n = 141) twice daily, 750 mg amoxicillin twice daily, 250 mg metronidazole twice daily for 7 days) eradication therapies. Successful eradication rates were compared between two groups: those receiving VPZ and those receiving a proton pump inhibitor (PPI). Adverse events were also investigated. Results: Successful second-line eradication rates according to ITT analysis and PP analysis, respectively, were 79.9% and 92.4% for VPZ therapy and 83.6% and 93.3% for PPI therapy. There were no significant differences between treatment groups. The eradication rates in those who had received first-line VPZ therapy previously according to ITT and PP analysis were 75.2% and 88.1%, respectively;in contrast, values were 82.5% and 95.4%, respectively, for those who had received first-line PPI therapy previously. In second-line therapy, the overall adverse event rate for VPZ therapy was the same as for PPI therapy. Conclusions: The efficacy and tolerability of metronidazole-containing second-line triple therapy with VPZ or a PPI were equivalent.展开更多
The present work aims to study the influence of some physicochemical parameters (light, temperature, ethanol, bile salts, potassium hydroxide, hydrogen peroxide) on the content of Metronidazole (MTZ) contained in the ...The present work aims to study the influence of some physicochemical parameters (light, temperature, ethanol, bile salts, potassium hydroxide, hydrogen peroxide) on the content of Metronidazole (MTZ) contained in the reference substance (SR) and in a pharmaceutical specialty Flagyl<sup>®</sup> 250 mg tablet (FLG). The method developed was linear and accurate in accordance with USP 38 and the MTZ contents were obtained by UV-visible spectrophotometry at 278 nm. These contents ranged from 225 mg to 275 mg and were thus consistent with the concentration present in the proprietary medicines (250 mg). The study of the influence of physicochemical parameters on the MTZ content in SR and FLG showed that MTZ contents are unstable in the presence of Ethanol at 96˚, KOH at 0.1N and bile salts but also when the temperature is higher than 25˚C. However, they remain stable in the presence of light and H<sub>2</sub>O<sub>2</sub> and undergo degradation in an acidic environment.展开更多
The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb10.8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscop...The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb10.8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscopy and UV-Vis absorption spectrum. Metronidazole is very stable and is difficult to degrade under UV irradiation. K6Nb10.8O30 photocatalyst cannot degrade metronidazole without UV irradiation and shows very high photo-catalytic activity for the degradation of metronidazole under UV irradiation. The photocatalytic degradation rate of metronidazole increased with increasing the dosage of K6Nb10.8O30 photocatalyst. The photocatalytic degradation reaction of metronidazole by nio-bate K6Nb10.8O30 follows the first-order kinetic equation.展开更多
Degradation of metronidazole (MNZ) which is a representative and stable antibiotic by dielectric barrier discharge (DBD) in an aqueous solution has been studied. Effects of initial MNZ concentration, solution pH and c...Degradation of metronidazole (MNZ) which is a representative and stable antibiotic by dielectric barrier discharge (DBD) in an aqueous solution has been studied. Effects of initial MNZ concentration, solution pH and coexisting organics on the degradation were investigated. The results illustrated that increasing the input power and the discharge frequency can improve the removal of MNZ. At low initial concentration, the removal of MNZ can reach up to 99.1%. Acidic and neutral conditions are more favorable for MNZ removal than alkaline condition in the early stage of degradation. However, the difference in MNZ removal between those in acidic or neutral media and that in alkaline one could be neglected with prolonging of the treatment time. Therefore, this method can be applied to MNZ degradation with a wide pH range. Coexisting organic matter in water can attenuate the removal to some extent. This study could provide valuable references for the degradation of nitroimidazole antibiotics by DBD.展开更多
Metronidazole(MTZ)is an important antibiotic,which has been widely applied to cure protozoal and bacterial diseases for human beings or animals.Herein,three novel drug supramolecular crystals constructed by MTZ with 2...Metronidazole(MTZ)is an important antibiotic,which has been widely applied to cure protozoal and bacterial diseases for human beings or animals.Herein,three novel drug supramolecular crystals constructed by MTZ with 2.5-dihydroxy-benzoic acid(2.5-DHBA)(1),2.6-dihydroxy-benzoic acid(2.6-DHBA)(2)and 3,5-dihydroxy-benzoic acid(3.5-DHBA)(3),respectively,have been discovered.The hydrogen bonds of N-H…O(O-H…N).C-H…O and O-H…O play important roles in the 3D supramolecular framework formation for crystals 1-3.Interestingly.due to the vary locations of the substituent groups,the two-dimensional layers in crystals 1 or 2 are constructed via intermolecular hydrogen bonds between MTZ and 2,5-DHBA or 2.6-DHBA,while in crystal 3 water molecules play a significant role except the intermolecular hydrogen bonds between MTZ and 3,5-DHBA.In addition,five synthons of I R^22(8),ⅡR3(9)in crystal 1,ⅢR1(4),ⅣR2(8)in crystal 2 andⅤR2(7)in crystal 3 formed through various hydrogen bonds are founded in this work.Systematic studies of syntheses,crystal structures and thermal analysis are reported.展开更多
Metronidazole(MTZ)loaded Eudragit S-100(ES-100)nonwoven nanofbrous mats were successfully electrospun and evaluated for intestinal drug delivery.MTZ was varied in the range of 1–15%(w/w)in ES-100 nanofbrous mats,the ...Metronidazole(MTZ)loaded Eudragit S-100(ES-100)nonwoven nanofbrous mats were successfully electrospun and evaluated for intestinal drug delivery.MTZ was varied in the range of 1–15%(w/w)in ES-100 nanofbrous mats,the morphological characterization of nanofbrous mats was carried out using FE-SEM and the average diameter of nanofber was found in the range 150–600 nm.WAXD and DSC demonstrated the amorphous nature of MTZ in ES-100 nanofbrous mats.Their contact angle analysis confrmed the hydrophobic nature.The mechanical strength of ES-100 nanofbrous mats decreased with increasing MTZ concentration.The drug release profles showed 74%MTZ release from ES-100d within 2 h at pH 6.8 which is the colonic environment.Antibacterial activities against gram-positive bacteria(Staphylococcus aureus)and gramnegative bacteria(Escherichia coli)showed that the ES-100 nanofbrous mats loaded with MTZ exhibited good activity.展开更多
Objective:To assess the pharmaceutical quality of different brands of metronidazole manufactured,available and prescribed by the doctors of Peshawar,Pakistan.Methods:Different film-coated metronidazole products manufa...Objective:To assess the pharmaceutical quality of different brands of metronidazole manufactured,available and prescribed by the doctors of Peshawar,Pakistan.Methods:Different film-coated metronidazole products manufactured by multinational and national pharmaceutical industries and prescribed by the doctors were collected from Peshawar,Khyber Pakhtunkhwa,Pakistan.Their hysico-chemical properties were assessed,which included friability,hardness,disintegration,dissolution and weight variation tests according to the the United States Pharmacopoeia(USP)standards.Results:All the brands showed a average weight of 5.74 g for 13 tablets(products A-M).Product J had the highest weight and products D and E failed the hardness,friability and disintegration time according to USP standards.Products M,K and G,L failed disintegration test and dissolution test,respectively.Weight variation of all the products proved statistically that they were in accordance with the standards of USP.Conclusions:The study suggested that products A,F,H and J passed all the tests according to the USP standards while the rest of them did not fulfill the standards specification.展开更多
AIM: To investigate the resistance of Helicobacter pylori (H. pylori ) to 6 commonly used antibiotics from 2000 to 2009 in Shanghai. METHODS: A total of 293 H. pylori strains were collected from 2000 to 2009 in Shangh...AIM: To investigate the resistance of Helicobacter pylori (H. pylori ) to 6 commonly used antibiotics from 2000 to 2009 in Shanghai. METHODS: A total of 293 H. pylori strains were collected from 2000 to 2009 in Shanghai and tested for their susceptibility to metronidazole, clarithromycin, amoxicillin, furazolidone, levofloxacin and tetracycline using agar dilution. RESULTS: The resistant rates of H. pylori to clarithromycin (8.6%, 9.0% and 20.7%) and levofloxacin (10.3%, 24.0% and 32.5%) increased from 2000 to 2009 in Shanghai. The resistant rate of H. pylori to metronidazole remained stable (40%-50%). Only one strain of H. pylori isolated in 2005 was resistant to tetracycline. All strains were sensitive to amoxicillin and furazolidone.The resistant rate of H. pylori to antibiotics was not related with the sex, age and clinical outcome of patients. CONCLUSION: Resistance of H. pylori to antibiotics plays an important role in making treatment strategies against H. pylori -associated diseases.展开更多
Helicobacter pylori(H. pylori) antibiotic resistance is the main factor affecting the efficacy of the current eradicating therapies. The aim of this editorial is to report on the recent information about the mechanism...Helicobacter pylori(H. pylori) antibiotic resistance is the main factor affecting the efficacy of the current eradicating therapies. The aim of this editorial is to report on the recent information about the mechanisms accounting for the resistance to the different antibiotics currently utilized in H. pylori eradicating treatments. Different mechanisms of resistance to clarithromycin,metronidazole,quinolones,amoxicillin and tetracycline are accurately detailed(point mutations,redox intracellular potential,pump efflux systems,membrane permeability) on the basis of the most recent data available from the literature. The next hope for the future is that by improving the knowledge of resistance mechanisms,the elaboration of rational and efficacious associations for the treatment of the infection will be possible. Another auspicious progress might be the possibility of a cheap,feasible and reliable laboratory test to predict the outcome of a therapeutic scheme.展开更多
Pelvic cancers are among the most frequently diagnosed neoplasms and radiotherapy represents one of the main treatment options. The irradiation field usually encompasses healthy intestinal tissue,especially of distal ...Pelvic cancers are among the most frequently diagnosed neoplasms and radiotherapy represents one of the main treatment options. The irradiation field usually encompasses healthy intestinal tissue,especially of distal large bowel,thus inducing gastrointestinal(GI) radiation-induced toxicity. Indeed,up to half of radiationtreated patients say that their quality of life is affected by GI symptoms(e.g.,rectal bleeding,diarrhoea). The constellation of GI symptoms- from transient to longterm,from mild to very severe- experienced by patients who underwent radiation treatment for a pelvic tumor have been comprised in the definition of pelvic radiation disease(PRD). A correct and evidence-based therapeutic approach of patients experiencing GI radiation-induced toxicity is mandatory. Therapeutic non-surgical strategies for PRD can be summarized in two broad categories,i.e.,medical and endoscopic. Of note,most of the studies have investigated the management of radiation-induced rectal bleeding. Patients with clinically significant bleeding(i.e.,causing chronic anemia) should firstly be considered for medical management(i.e.,sucralfate enemas,metronidazole and hyperbaric oxygen); in case of failure,endoscopic treatment should be implemented. This latter should be considered the first choice in case of acute,transfusion requiring,bleeding. More well-performed,high quality studies should be performed,especially the role of medical treatments should be better investigated as well as the comparative studies between endoscopic and hyperbaric oxygen treatments.展开更多
Toxic megacolon is a severe complication of Clostridium difficile (C.difficile) colitis.As the prevalence of C. difficile colitis increases and treatments become more refractory, clinicians will encounter more patient...Toxic megacolon is a severe complication of Clostridium difficile (C.difficile) colitis.As the prevalence of C. difficile colitis increases and treatments become more refractory, clinicians will encounter more patients with C. difficile associated toxic megacolon in the future. Here, we review a case of toxic megacolon secondary to C. difficile colitis and review the current literature on diagnosis and management. We identify both clinical and radiologic criteria for diagnosis and discuss both medical and surgical options for management. Ultimately, we recommend using the Jalen criteria in conjunction with daily abdominal radiographs to help establish the diagnosis of toxic megacolon and to make appropriate treatment recommendations. Aggressive medical management using supportive measures and antibiotics should remain the mainstay of treatment. Surgical intervention should be considered if the patient does not clinically improve within 2-3 d of initial treatment.展开更多
基金the National University of Singapore Grant GR6431.
文摘INTRODUCTIONEradication of Helicobacter pylori,a bacteriumresiding in stomach and causing peptic ulcer disease,can be achieved by using combination therapiesconsisting of one or two antibiotics with a protonpump inhibitor (PPI).The major antibiotics widelyused in the regimens to eradicate H.pylori aremetronidazole and clarithromycin.However,resistance to these antibiotics by H.pylori
基金financially supported by the National Natural Science Foundation of China(Grant Nos.21475046,21427809)
文摘An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis.
基金Supported by Grant from the Ministry of Science,Technology and Innovation,Malaysia,No.06-02-0055-PR0073/05
文摘AIM:To characterise the cag pathogenicity island in Helicobacter pylori(H.pylori) isolates by analysing the strains' vacA alleles and metronidazole susceptibilities in light of patient ethnicity and clinical outcome.METHODS:Ninety-five H.pylori clinical isolates obtained from patients with dyspepsia living in Malaysia were analysed in this study.Six genes in the cagPAI region(cagE,cagM,cagT,cag13,cag10 and cag67) andvacA alleles of theH.pylori isolates were identified by polymerase chain reaction.The isolates' metronidazole susceptibility was also determined using the E-test method,and the resistant gene was characterised by sequencing.RESULTS:More than 90% of the tested isolates had at least one gene in the cagPAI region,and cag67 was predominantly detected in the strains isolated from the Chinese patients,compared with the Malay and Indian patients(P < 0.0001).The majority of the isolates(88%) exhibited partial deletion(rearrangement) in the cagPAI region,with nineteen different patterns observed.Strains with intact or deleted cagPAI regions were detected in 3.2% and 8.4% of isolates,respectively.The prevalence of vacA s1m1 was significantly higher in the Malay and Indian isolates,whereas the isolates from the Chinese patients were predominantly genotyped as vacA s1m2(P = 0.018).Additionally,the isolates from the Chinese patients were more sensitive to metronidazole than the isolates from the Malay and Indian patients(P = 0.047).Although we attempted to relate the cagPAI genotypes,vacA alleles and metronidazole susceptibilities to disease outcome,no association was observed.The vacA alleles were distributed evenly among the strains with intact,partially deleted or deleted cagPAI regions.Interestingly,the strains exhibiting an intact cagPAI region were sensitive to metronidazole,whereas the strains with a deleted cagPAI were more resistant.CONCLUSION:Successful colonisation by different H.pylori genotypes is dependent on the host's genetic makeup and may play an important role in the clinical outcome.
基金The authors gratefully acknowledge the financial support granted by CNPq,INEO,CAPES and FAPESP(Grant Nos.:2018/22214-6,2017/24053-7 and 2016/0991-5).
文摘Monitoring the concentration of antibiotics in body fluids is essential to optimizing the therapy and minimizing the risk of bacteria resistance,which can be made with electrochemical sensors tailored with appropriate materials.In this paper,we report on sensors made with screen-printed electrodes(SPE)coated with fullerene(C60),reduced graphene oxide(rGO)and Nafion(NF)(C60-rGO-NF/SPE)to determine the antibiotic metronidazole(MTZ).Under optimized conditions,the C60-rGO-NF/SPE sensor exhibited a linear response in square wave voltammetry for MTZ concentrations from 2.5×10^(-7) to 34×10^(-6) mol/L,with a detection limit of 2.1×10^(-7) mol/L.This sensor was also capable of detecting MTZ in serum and urine,with recovery between 94%and 100%,which are similar to those of the standard chromatographic method(HPLC-UV).Because the C60-rGO-NF/SPE sensor is amenable to mass production and allows for MTZ determination with simple principles of detection,it fulfills the requirements of therapeutic drug monitoring programs.
基金This work was supported by the National Natural Science Foundation of China(21725601).
文摘Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this issue.In this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was evaluated.Major intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed herein.This plasma-catalytic process has bright prospects in the field of antibiotics degradation.
基金financially supported by Immunology Research Center,Tabriz University of Medical Sciences,Tabriz,Iranthe master’s thesis of the first author(Thesis No.93/2-4/12)
文摘Objective:To identify the frequencies(F) of ferredoxin and nitroreductase mutations were identified on Iranian clinical isolates of Giardia lamblia in order to predict whether the nitazoxanide can be prescribed as suitable drug for symptomatic to metronidazoleresistant giardiasis.Methods:Forty Giardia lamblia isolates as of 38 symptomatic and two metronidazole-resistant patients were collected from Iran.DNAs were extracted and amplified by targeting ferredoxin and Gl NR genes.The amplicons were directly sequenced to determine gene mutations.Results:The various amino acid substitutions(F:20%,Haplotype diversity:0.891,Tajima's D:-0.44013) were identified by analyzing ferredoxin gene in four symptomatic and two resistant isolates.Only,two haplotypes(F:5%,HD:0.345; Tajima's D:0.77815) characterized in metronidazole-resistant isolates of Gl NR,however,no point mutations was found in symptomatic isolates.Conclusions:Non-synonymous mutations of ferredoxin oxidoreductase gene reduce translational regulatory protein's binding affinity which concludes reduction of ferredoxin expression and its activity.This leads to decrease in metronidazole drug delivery into the cells.Mutations in these isolates may lead to their resistance to metronidazole.No to low synonymous mutations of Gl NR demonstrates that nitazoxanide can be prescribed as promising alternative treatment for symptomatic to metronidazole-resistant giardiasis in Iranian clinical isolates.
基金Supported by the research center of Infectious & Tropical Diseases-Tabriz University of Medical Sciences(Grant No.9108)
文摘Objective:To compare effect of Hypericum perforatum(H.perforatum) vaginal gel with metronidazole on bacterial vaginosis(BV) in terms of initial response to treatment and preventing recurrence(primary outcomes) and also patient complaints(secondary outcomes).Methods:In this double-blind,double dummy trial,married women aged 18-49 with BV were randomized into two groups and administered 5 g of 3%H.perforatum and placebo of metronidazole(n=82),or 5 g of 0.75%metronidazole and placebo of H.peiforatum(n=80)vaginally for 5 d.Amsel criteria were used for diagnosis and assessing cure and recurrence of BV.The comparisons was done using Chi-square,Fisher's exact and logistic regression.Results:At 10-12 d.cure rate was 82%in the H.perforatum and 85%in metronidazole group(risk ratio 0.9.95%confidence interval 0.6 to 1.3).Among the cured women,recurrence rate was 9%in the H.perforatum and 13%in the metronidazole group at the 30-35 d visit(risk ratio 0.8,95%confidence interval 0.4 to 1.3),There was no statistically significant difference between the groups regarding any patient complaints,except itching which was less in H.perforatum group(5%vs.16%,P=0.018 at the first and 13%vs.43%,P<0.001 at the second follow-up).No significant adverse event was reported at any groups.Conclusions:H.peiforatum could be a good option for treatment of BV.However,further studies arc needed for its public use.
文摘Aim: To investigate the efficacy and tolerability of second-line metronidazole triple therapy with vonoprazan (VPZ) for Helicobacter pylori (H. pylori). Methods: We retrospectively reviewed medical records of patients who experienced clarithromycin triple therapy failure and were treated with second-line (20 mg VPZ (n = 274)/30 mg lansoprazole (n = 323) or 10 mg rabeprazole (n = 141) twice daily, 750 mg amoxicillin twice daily, 250 mg metronidazole twice daily for 7 days) eradication therapies. Successful eradication rates were compared between two groups: those receiving VPZ and those receiving a proton pump inhibitor (PPI). Adverse events were also investigated. Results: Successful second-line eradication rates according to ITT analysis and PP analysis, respectively, were 79.9% and 92.4% for VPZ therapy and 83.6% and 93.3% for PPI therapy. There were no significant differences between treatment groups. The eradication rates in those who had received first-line VPZ therapy previously according to ITT and PP analysis were 75.2% and 88.1%, respectively;in contrast, values were 82.5% and 95.4%, respectively, for those who had received first-line PPI therapy previously. In second-line therapy, the overall adverse event rate for VPZ therapy was the same as for PPI therapy. Conclusions: The efficacy and tolerability of metronidazole-containing second-line triple therapy with VPZ or a PPI were equivalent.
文摘The present work aims to study the influence of some physicochemical parameters (light, temperature, ethanol, bile salts, potassium hydroxide, hydrogen peroxide) on the content of Metronidazole (MTZ) contained in the reference substance (SR) and in a pharmaceutical specialty Flagyl<sup>®</sup> 250 mg tablet (FLG). The method developed was linear and accurate in accordance with USP 38 and the MTZ contents were obtained by UV-visible spectrophotometry at 278 nm. These contents ranged from 225 mg to 275 mg and were thus consistent with the concentration present in the proprietary medicines (250 mg). The study of the influence of physicochemical parameters on the MTZ content in SR and FLG showed that MTZ contents are unstable in the presence of Ethanol at 96˚, KOH at 0.1N and bile salts but also when the temperature is higher than 25˚C. However, they remain stable in the presence of light and H<sub>2</sub>O<sub>2</sub> and undergo degradation in an acidic environment.
基金Supported by Program for New Century Excellent Talents in University (NCET05-0662)
文摘The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb10.8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscopy and UV-Vis absorption spectrum. Metronidazole is very stable and is difficult to degrade under UV irradiation. K6Nb10.8O30 photocatalyst cannot degrade metronidazole without UV irradiation and shows very high photo-catalytic activity for the degradation of metronidazole under UV irradiation. The photocatalytic degradation rate of metronidazole increased with increasing the dosage of K6Nb10.8O30 photocatalyst. The photocatalytic degradation reaction of metronidazole by nio-bate K6Nb10.8O30 follows the first-order kinetic equation.
文摘Degradation of metronidazole (MNZ) which is a representative and stable antibiotic by dielectric barrier discharge (DBD) in an aqueous solution has been studied. Effects of initial MNZ concentration, solution pH and coexisting organics on the degradation were investigated. The results illustrated that increasing the input power and the discharge frequency can improve the removal of MNZ. At low initial concentration, the removal of MNZ can reach up to 99.1%. Acidic and neutral conditions are more favorable for MNZ removal than alkaline condition in the early stage of degradation. However, the difference in MNZ removal between those in acidic or neutral media and that in alkaline one could be neglected with prolonging of the treatment time. Therefore, this method can be applied to MNZ degradation with a wide pH range. Coexisting organic matter in water can attenuate the removal to some extent. This study could provide valuable references for the degradation of nitroimidazole antibiotics by DBD.
基金Supported by the National Natural Science Foundation of China(Nos.21801150,51802170,51772162)the Outstanding Youth Foundation of Shandong Province,China(No.ZR2019J014)+1 种基金the Youth Innovation and Technology Foundation of Shandong Higher Education Institutions,China(No.2019KJC004)the Taishan Scholar Young Talent Program and the Major Scientific and Technological Innovation Project,China(No.2019172Y020405)。
文摘Metronidazole(MTZ)is an important antibiotic,which has been widely applied to cure protozoal and bacterial diseases for human beings or animals.Herein,three novel drug supramolecular crystals constructed by MTZ with 2.5-dihydroxy-benzoic acid(2.5-DHBA)(1),2.6-dihydroxy-benzoic acid(2.6-DHBA)(2)and 3,5-dihydroxy-benzoic acid(3.5-DHBA)(3),respectively,have been discovered.The hydrogen bonds of N-H…O(O-H…N).C-H…O and O-H…O play important roles in the 3D supramolecular framework formation for crystals 1-3.Interestingly.due to the vary locations of the substituent groups,the two-dimensional layers in crystals 1 or 2 are constructed via intermolecular hydrogen bonds between MTZ and 2,5-DHBA or 2.6-DHBA,while in crystal 3 water molecules play a significant role except the intermolecular hydrogen bonds between MTZ and 3,5-DHBA.In addition,five synthons of I R^22(8),ⅡR3(9)in crystal 1,ⅢR1(4),ⅣR2(8)in crystal 2 andⅤR2(7)in crystal 3 formed through various hydrogen bonds are founded in this work.Systematic studies of syntheses,crystal structures and thermal analysis are reported.
基金Ms.Priyanka P.Rade gratefully acknowledges the Department of Science and Technology,New Delhi,India for the award of DST-INSPIRE fellowship(IF160594)for her doctoral researchThe authors also gratefully acknowledge LIA MATSUCAT,France for the collaborationThe authors express their heartfelt gratitude to Evonik Industries,Mumbai,India,for providing Eudragit S 100 as a gift sample.
文摘Metronidazole(MTZ)loaded Eudragit S-100(ES-100)nonwoven nanofbrous mats were successfully electrospun and evaluated for intestinal drug delivery.MTZ was varied in the range of 1–15%(w/w)in ES-100 nanofbrous mats,the morphological characterization of nanofbrous mats was carried out using FE-SEM and the average diameter of nanofber was found in the range 150–600 nm.WAXD and DSC demonstrated the amorphous nature of MTZ in ES-100 nanofbrous mats.Their contact angle analysis confrmed the hydrophobic nature.The mechanical strength of ES-100 nanofbrous mats decreased with increasing MTZ concentration.The drug release profles showed 74%MTZ release from ES-100d within 2 h at pH 6.8 which is the colonic environment.Antibacterial activities against gram-positive bacteria(Staphylococcus aureus)and gramnegative bacteria(Escherichia coli)showed that the ES-100 nanofbrous mats loaded with MTZ exhibited good activity.
文摘Objective:To assess the pharmaceutical quality of different brands of metronidazole manufactured,available and prescribed by the doctors of Peshawar,Pakistan.Methods:Different film-coated metronidazole products manufactured by multinational and national pharmaceutical industries and prescribed by the doctors were collected from Peshawar,Khyber Pakhtunkhwa,Pakistan.Their hysico-chemical properties were assessed,which included friability,hardness,disintegration,dissolution and weight variation tests according to the the United States Pharmacopoeia(USP)standards.Results:All the brands showed a average weight of 5.74 g for 13 tablets(products A-M).Product J had the highest weight and products D and E failed the hardness,friability and disintegration time according to USP standards.Products M,K and G,L failed disintegration test and dissolution test,respectively.Weight variation of all the products proved statistically that they were in accordance with the standards of USP.Conclusions:The study suggested that products A,F,H and J passed all the tests according to the USP standards while the rest of them did not fulfill the standards specification.
基金Supported by National Natural Science Foundation of China,No. 30770112Shanghai Leading Academic Discipline Project, No. Y0205
文摘AIM: To investigate the resistance of Helicobacter pylori (H. pylori ) to 6 commonly used antibiotics from 2000 to 2009 in Shanghai. METHODS: A total of 293 H. pylori strains were collected from 2000 to 2009 in Shanghai and tested for their susceptibility to metronidazole, clarithromycin, amoxicillin, furazolidone, levofloxacin and tetracycline using agar dilution. RESULTS: The resistant rates of H. pylori to clarithromycin (8.6%, 9.0% and 20.7%) and levofloxacin (10.3%, 24.0% and 32.5%) increased from 2000 to 2009 in Shanghai. The resistant rate of H. pylori to metronidazole remained stable (40%-50%). Only one strain of H. pylori isolated in 2005 was resistant to tetracycline. All strains were sensitive to amoxicillin and furazolidone.The resistant rate of H. pylori to antibiotics was not related with the sex, age and clinical outcome of patients. CONCLUSION: Resistance of H. pylori to antibiotics plays an important role in making treatment strategies against H. pylori -associated diseases.
文摘Helicobacter pylori(H. pylori) antibiotic resistance is the main factor affecting the efficacy of the current eradicating therapies. The aim of this editorial is to report on the recent information about the mechanisms accounting for the resistance to the different antibiotics currently utilized in H. pylori eradicating treatments. Different mechanisms of resistance to clarithromycin,metronidazole,quinolones,amoxicillin and tetracycline are accurately detailed(point mutations,redox intracellular potential,pump efflux systems,membrane permeability) on the basis of the most recent data available from the literature. The next hope for the future is that by improving the knowledge of resistance mechanisms,the elaboration of rational and efficacious associations for the treatment of the infection will be possible. Another auspicious progress might be the possibility of a cheap,feasible and reliable laboratory test to predict the outcome of a therapeutic scheme.
文摘Pelvic cancers are among the most frequently diagnosed neoplasms and radiotherapy represents one of the main treatment options. The irradiation field usually encompasses healthy intestinal tissue,especially of distal large bowel,thus inducing gastrointestinal(GI) radiation-induced toxicity. Indeed,up to half of radiationtreated patients say that their quality of life is affected by GI symptoms(e.g.,rectal bleeding,diarrhoea). The constellation of GI symptoms- from transient to longterm,from mild to very severe- experienced by patients who underwent radiation treatment for a pelvic tumor have been comprised in the definition of pelvic radiation disease(PRD). A correct and evidence-based therapeutic approach of patients experiencing GI radiation-induced toxicity is mandatory. Therapeutic non-surgical strategies for PRD can be summarized in two broad categories,i.e.,medical and endoscopic. Of note,most of the studies have investigated the management of radiation-induced rectal bleeding. Patients with clinically significant bleeding(i.e.,causing chronic anemia) should firstly be considered for medical management(i.e.,sucralfate enemas,metronidazole and hyperbaric oxygen); in case of failure,endoscopic treatment should be implemented. This latter should be considered the first choice in case of acute,transfusion requiring,bleeding. More well-performed,high quality studies should be performed,especially the role of medical treatments should be better investigated as well as the comparative studies between endoscopic and hyperbaric oxygen treatments.
文摘Toxic megacolon is a severe complication of Clostridium difficile (C.difficile) colitis.As the prevalence of C. difficile colitis increases and treatments become more refractory, clinicians will encounter more patients with C. difficile associated toxic megacolon in the future. Here, we review a case of toxic megacolon secondary to C. difficile colitis and review the current literature on diagnosis and management. We identify both clinical and radiologic criteria for diagnosis and discuss both medical and surgical options for management. Ultimately, we recommend using the Jalen criteria in conjunction with daily abdominal radiographs to help establish the diagnosis of toxic megacolon and to make appropriate treatment recommendations. Aggressive medical management using supportive measures and antibiotics should remain the mainstay of treatment. Surgical intervention should be considered if the patient does not clinically improve within 2-3 d of initial treatment.
