AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhiz...AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhizoma coptidis has been used for more than two thousand years in China to treat diarrhea, fever, and jaundice. In this study, the anti-MRSA activity of Rhizoma coptidis is examined and its effective components sought. METHODS： The mecA and norA genes were determined by PCR amplification and sequencing. Drug susceptibility of Staphylococcus aureus ATCC43300 was performed using the VITEK2 compact system. The chemical fingerprint of Rhizoma coptidis was investigated using HPLC and preparative liquid chromatography, and the anti-MRSA activity was determined using an improved broth microdilution method. RESULTS： The drug susceptibility test revealed that the penicillin-binding protein phenotype of the strain changed in comparison to penicillin-sensitive Staphylococcus aureus. Ten batches of Rhizoma coptidis showed anti-MRSA activity on the norA-negative Staphylococcus aureus strain, as well as the strain that contained a norA gene. The spectrum-effect relationship revealed that the berberine alkaloids were the effective components, within which berberine, coptisine, palmatine, epiberberine,, and jatrorrhizine were the major components. CONCLUSION： This study lays a foundation for in vivo studies of Rhizoma eoptidis and for the development of multi-component drugs.展开更多
In dairy and food industries lactic acid bacteria （LAB） have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing e...In dairy and food industries lactic acid bacteria （LAB） have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing evidence that lactobacilli which inhabit the gastrointestinal tract develop antimicrobial activities and participate in the host＇s defence system[1]. During fermentation, most of the LAB produces a number of different compounds like organic acids, hydrogen peroxide, diacetyl, acetaldehyde, carbon dioxide, polysaccharides, and proteinaceous compounds called bacteriocins or bacteriocinogenic peptides.展开更多
Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibito...Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibitory concentrations（MICs）. Methods：Isolates were collected from clinical patients with UU infection, and cultured in UU broth. In order to test the different effects on clinical strains of UU, the assays were performed by microdilution inhibition tests, and MICs of the herbs against the clinical strains of UU were calculated. Results：The MICs of eight pure herbs against clinical strains of UU were as follows： Galla Chinensis：0.313-1.25 g/L; Fructus Forsythiae： 1.25-5.00 g/L; Cortex Phellodendri： 1.25-5.00 g/L; Radix Paeoniae Rubra： 1.25-2.50 g/L; Semen Plantaginis：2.50-10.00 g/L; Herba Lysimachiae： 5.00-20.00 g/L; Rhizoma Coptidis： 5.00-20.00g/L, Herba Houttuyniae： 10.00-20.00 g/L. The MICs of compound herbs were： Liuheji： 0.625-2.50 g/L; Bazhengsan： 5.00-20.00 g/L; Wulinsan：2.50-20.0 g/L.Conclusion：Galla Chinensis, Fructus Forsythiae, Cortex Phellodendrim, Radix Paeoniae Rubra, and Semen Plantaginis, exerted the stronger antibacterial effect against clinical strains of UU, whereas Herba Lysimachiae, Rhizoma Coptidis and Herba Houttuyniae, had relatively weaker activity against UU. Compound herbs, Bazhengsan and Wulinsan, and particularly Liuheji, also had antibacterial effects against UU. Further studies of the effects and mechanisms of action of Chinese crude drugs against UU infections are worthwhile.展开更多
Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,an...Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,and Rosa damascena alone and then synergy testing of these extracts with known antimicrobial agents including oxytetracycline HCl,gentamicin sulfate,penicillin G,cephalexin and enrofloxacin.This study was conducted against five S.aureus isolates;one is Methicillin -resistant Staphylococcus aureus(MRSA) and 4 Methicillin - sensitive Staphylococcus aureus(MSSA).Methods:Evaluation of the interaction between plant extracts and different antimicrobial agents has been done using well - diffusion and microdilution methods. Results:The results of the conducted experiments using well - diffusion method demonstrate that these plants showed in vitro interactions between antimicrobial agents and plant extracts were additive,while using microdilution method showed synergistic effects with significant reduction in the MICs of the test antibiotics against these strains of S.aureus.This change in MIC was noticed in all plant extracts against test antibiotics including these plants showed weak antibacterial activity by well diffusion method.Synergism effect was occurred in both sensitive and resistant strains but the magnitude of minimum fold reduction of inhibitory concentration in resistant strains especially MRSA strain was higher than the sensitive strains.Coclusion:This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S.aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.展开更多
The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by ep...The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by epidemiological cut-off(ECOFF)finder against E.coli from chickens in China.Anal swabs were collected from chicken farms in China.BMD method was used to measure MIC50 and MIC90 of colistin which were 2 and 4μg•mL^(-1),respectively.MIC frequency distributions for colistin were used to estimate preliminary ECV(8μg•mL^(-1)).High percentages of resistance to ampicillin(94.12%),nalidixic acid(94.12%),enrofloxacin(94.12%),tetracycline(94.12%),ciprofloxacin(88.24%),florfenicol(88.24%),neomycin(64.71%),gentamicin(58.82%),levofloxacin(58.82%),doxycycline(88.24%)and cefalexin(76.47%)were found.In addition,low percentages of resistance to amikacin(5.88%),spectinomycin(17.65%)and fosfomycin(41.18%)were noted.Notably,amoxicillin,sulfisoxazole and trimethoprim resulted in a 100%resistance generation efficacy rate.Prevalence of mcr-1 in E.coli(9/17)in chromosomal DNA was higher than mcr-4(2/17)gene,and mcr-1(5/17)was higher than mcr-4(3/17)in plasmid.展开更多
[Objective] The aim was to explore the antibacterial effect of in -vitro combined application of imipenem and ceftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox on E. coliATCC25922. [Methods] Th...[Objective] The aim was to explore the antibacterial effect of in -vitro combined application of imipenem and ceftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox on E. coliATCC25922. [Methods] The minimum inhibition concentration of all kinds of the drugs to E. co/i ATCC25922 was determined and bacteriostatic effect of imipenem and ceffriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox on E. coli ATCC＇25922 was determined with chessboard microdilution method. [ Results] Combined applications of imipenem and caftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox to E. coli ATCC25922 revealed synergistic effects. [ Ceedusion] Combined applications of imipenem and ceftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox greatly reduced drug dosa,qe, imDroved the druq effect, and provided theoretical support for clinical medicine.展开更多
[Objective] The paper was to investigate in vitro antibacterial effect of alkaline hydrogen water on Escherichia coli,Salmonella,Pseudomonas aeruginosa and Staphylococcus aureus.[Method] With Cortex cinnamomi extract...[Objective] The paper was to investigate in vitro antibacterial effect of alkaline hydrogen water on Escherichia coli,Salmonella,Pseudomonas aeruginosa and Staphylococcus aureus.[Method] With Cortex cinnamomi extract（1 g/m L） and pure water as the control,the minimal inhibitory concentrations（MIC） against four kinds of common pathogenic microorganisms were tested through microdilution method.[Result] When the alkaline hydrogen water was diluted to 1/8 times of the original concentration,it had significant antibacterial effects on four kinds of common mi-croorganisms with the concentration of 1.5 ×10^5 CFU/m L,which had equivalent effect with C.cinnamomi extract group.[Conclusion]The alkaline hydrogen water has remarkable antibacterial effects on the four kinds of common microorganisms,which may provide a new important way for pre-venting disease occurrence and reducing the harms of pathogenic microorganisms.展开更多
[ Objective] This paper aimed to understand drug resistance of Escherichia coli isolated from pets in Guangzhou. I Method ] Broth microdilution method was used to determine the minimal inhibitory concentration （MIC）...[ Objective] This paper aimed to understand drug resistance of Escherichia coli isolated from pets in Guangzhou. I Method ] Broth microdilution method was used to determine the minimal inhibitory concentration （MIC） of ceftiofur, enrofloxacin and other 11 kinds of antibiotics for antimicrobial agent susceptibility testing of 120 strains of clinical E. coli and the experimental data were processed by WHONET 5.4 software. Based on the results of drug resistance pattern analysis, it helped to analyze and study the resistance mechanism. EResultl Clinical E. coli isolated from pets showed a different drug resistance to the 13 kinds of veterinary clinical antibiotics, and the different sources of E. coli also showed a different drug resistance pattern.[Cenclmion] The study provided a theoretical basis for the clinical use of drugs and druq resistance surveillance.展开更多
Mycobacteria constitute vast population of bacteria that are found in animals, plants and outer environments. Tuberculosis mycobacteria are a group that causes very dangerous diseases for human and animals. Nontubercu...Mycobacteria constitute vast population of bacteria that are found in animals, plants and outer environments. Tuberculosis mycobacteria are a group that causes very dangerous diseases for human and animals. Nontuberculous mycobacteria are mainly environmental and are pathogenic in certain circumstances. There are reports of finding mycobacteria in plant tissues, which can be effective to survey in case of different infectious disease issues. In a previous study, we found mycobacteria strains in alfalfa vascular tissues and identified them to species level using 16S rRNA gene sequence analysis, causing some symptoms in plant tissues and aerial parts. As these rapidly growing mycobacteria (RGM) have the potential to cause opportunistic infections in human tissues, one of the most important issues for dealing with these agents is to find the best and most effective drug to treat them. Here, we conducted some assays to investigate the MIC of 7 antibiotics and two antibacterial agents against eight Mycobacterium frederiksbergense alfalfa isolated strains, in order to find the susceptible and resistant ones. We performed susceptibility testing based on broth microdilution method using Mueller hinton broth as the medium used. Results were different among the strains and different resistant and susceptible reactions were observed among different strains against each drug tested, but ethambutol resulted in similar high MIC for all of them. This variability could be attributed to many factors, such as plant tissue composition and developmental stage from which the strains have been isolated, existence and nature of drug targets and other factors such as test conditions and environmental causes. These results can bring us some insights into design and develop new drugs for treating these kinds of organisms, based on the variations in susceptibility reactions and the plant composition effect on them.展开更多
Introduction:Nocardia species are found worldwide in soil rich in organic matter and can cause nocardiosis in humans.Trimethoprimsulfamethoxazole has long been the first-line treatment for Nocardia infections;however,...Introduction:Nocardia species are found worldwide in soil rich in organic matter and can cause nocardiosis in humans.Trimethoprimsulfamethoxazole has long been the first-line treatment for Nocardia infections;however,resistance to this therapy has recently been reported.Methods:Sixty-three clinical Nocardia isolates collected in China were tested against 32 antimicrobial agents using the broth microdilution method.Phylogenetic analysis of the 16S rRNA gene was performed to identify the species.Results:Three sequences from samples collected in Hainan Province did not match any known Nocardia species,suggesting significant genetic diversity among Nocardia isolates.Nocardia strains generally exhibited high resistance to clarithromycin,clindamycin,and isoniazid.Clinical and reference strains of N.farcinica and N.otitidiscaviarum were susceptible to amikacin and linezolid.Amoxicillin-clavulanate and imipenem were effective against all clinical and reference strains of N.farcinica,whereas gentamicin was effective against all clinical and reference strains of N.otitidiscaviarum.Conclusions:Linezolid and amikacin were the most consistently active drugs among the analyzed species.Variability of antimicrobial susceptibility was observed among clinical isolates of the same species and between clinical and reference isolates of the same species.Overall,this study highlights the need for better assessment of the burden of nocardiosis in China and for continuous monitoring of antimicrobial resistance among Nocardia isolates.展开更多
To performance susceptibility testing of antifungal agents Due to the increasing number of resistant strains, susceptibility testing of antifungal agents is gaining importance Methods We compared the results of s...To performance susceptibility testing of antifungal agents Due to the increasing number of resistant strains, susceptibility testing of antifungal agents is gaining importance Methods We compared the results of standard macrotube dilution reference method with two different microdilution methods, as well as the disc diffusion method in order to test the susceptibility of 150 Candida strains to fluconazole Results Overall correlation between microdilution and macrodilution methods was 86% It was 91% between the Minimal Inhibitory Concentrations obtained from macrodilution and disc diffusion zone diameters Conclusion The disc diffusion test was evaluated as a low-cost, reproducible, and efficient way of assessing the in vitro susceptibility of Candida strains to fluconazole展开更多
基金supported by the National Natural Science Foundation of China(No.81073043)
文摘AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhizoma coptidis has been used for more than two thousand years in China to treat diarrhea, fever, and jaundice. In this study, the anti-MRSA activity of Rhizoma coptidis is examined and its effective components sought. METHODS： The mecA and norA genes were determined by PCR amplification and sequencing. Drug susceptibility of Staphylococcus aureus ATCC43300 was performed using the VITEK2 compact system. The chemical fingerprint of Rhizoma coptidis was investigated using HPLC and preparative liquid chromatography, and the anti-MRSA activity was determined using an improved broth microdilution method. RESULTS： The drug susceptibility test revealed that the penicillin-binding protein phenotype of the strain changed in comparison to penicillin-sensitive Staphylococcus aureus. Ten batches of Rhizoma coptidis showed anti-MRSA activity on the norA-negative Staphylococcus aureus strain, as well as the strain that contained a norA gene. The spectrum-effect relationship revealed that the berberine alkaloids were the effective components, within which berberine, coptisine, palmatine, epiberberine,, and jatrorrhizine were the major components. CONCLUSION： This study lays a foundation for in vivo studies of Rhizoma eoptidis and for the development of multi-component drugs.
文摘In dairy and food industries lactic acid bacteria （LAB） have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing evidence that lactobacilli which inhabit the gastrointestinal tract develop antimicrobial activities and participate in the host＇s defence system[1]. During fermentation, most of the LAB produces a number of different compounds like organic acids, hydrogen peroxide, diacetyl, acetaldehyde, carbon dioxide, polysaccharides, and proteinaceous compounds called bacteriocins or bacteriocinogenic peptides.
文摘Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibitory concentrations（MICs）. Methods：Isolates were collected from clinical patients with UU infection, and cultured in UU broth. In order to test the different effects on clinical strains of UU, the assays were performed by microdilution inhibition tests, and MICs of the herbs against the clinical strains of UU were calculated. Results：The MICs of eight pure herbs against clinical strains of UU were as follows： Galla Chinensis：0.313-1.25 g/L; Fructus Forsythiae： 1.25-5.00 g/L; Cortex Phellodendri： 1.25-5.00 g/L; Radix Paeoniae Rubra： 1.25-2.50 g/L; Semen Plantaginis：2.50-10.00 g/L; Herba Lysimachiae： 5.00-20.00 g/L; Rhizoma Coptidis： 5.00-20.00g/L, Herba Houttuyniae： 10.00-20.00 g/L. The MICs of compound herbs were： Liuheji： 0.625-2.50 g/L; Bazhengsan： 5.00-20.00 g/L; Wulinsan：2.50-20.0 g/L.Conclusion：Galla Chinensis, Fructus Forsythiae, Cortex Phellodendrim, Radix Paeoniae Rubra, and Semen Plantaginis, exerted the stronger antibacterial effect against clinical strains of UU, whereas Herba Lysimachiae, Rhizoma Coptidis and Herba Houttuyniae, had relatively weaker activity against UU. Compound herbs, Bazhengsan and Wulinsan, and particularly Liuheji, also had antibacterial effects against UU. Further studies of the effects and mechanisms of action of Chinese crude drugs against UU infections are worthwhile.
文摘Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,and Rosa damascena alone and then synergy testing of these extracts with known antimicrobial agents including oxytetracycline HCl,gentamicin sulfate,penicillin G,cephalexin and enrofloxacin.This study was conducted against five S.aureus isolates;one is Methicillin -resistant Staphylococcus aureus(MRSA) and 4 Methicillin - sensitive Staphylococcus aureus(MSSA).Methods:Evaluation of the interaction between plant extracts and different antimicrobial agents has been done using well - diffusion and microdilution methods. Results:The results of the conducted experiments using well - diffusion method demonstrate that these plants showed in vitro interactions between antimicrobial agents and plant extracts were additive,while using microdilution method showed synergistic effects with significant reduction in the MICs of the test antibiotics against these strains of S.aureus.This change in MIC was noticed in all plant extracts against test antibiotics including these plants showed weak antibacterial activity by well diffusion method.Synergism effect was occurred in both sensitive and resistant strains but the magnitude of minimum fold reduction of inhibitory concentration in resistant strains especially MRSA strain was higher than the sensitive strains.Coclusion:This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S.aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.
基金Supported by the National Key Research and Development Program of China(2016YFD0501302)the National Natural Science Foundation of China(31772801)。
文摘The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by epidemiological cut-off(ECOFF)finder against E.coli from chickens in China.Anal swabs were collected from chicken farms in China.BMD method was used to measure MIC50 and MIC90 of colistin which were 2 and 4μg•mL^(-1),respectively.MIC frequency distributions for colistin were used to estimate preliminary ECV(8μg•mL^(-1)).High percentages of resistance to ampicillin(94.12%),nalidixic acid(94.12%),enrofloxacin(94.12%),tetracycline(94.12%),ciprofloxacin(88.24%),florfenicol(88.24%),neomycin(64.71%),gentamicin(58.82%),levofloxacin(58.82%),doxycycline(88.24%)and cefalexin(76.47%)were found.In addition,low percentages of resistance to amikacin(5.88%),spectinomycin(17.65%)and fosfomycin(41.18%)were noted.Notably,amoxicillin,sulfisoxazole and trimethoprim resulted in a 100%resistance generation efficacy rate.Prevalence of mcr-1 in E.coli(9/17)in chromosomal DNA was higher than mcr-4(2/17)gene,and mcr-1(5/17)was higher than mcr-4(3/17)in plasmid.
文摘[Objective] The aim was to explore the antibacterial effect of in -vitro combined application of imipenem and ceftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox on E. coliATCC25922. [Methods] The minimum inhibition concentration of all kinds of the drugs to E. co/i ATCC25922 was determined and bacteriostatic effect of imipenem and ceffriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox on E. coli ATCC＇25922 was determined with chessboard microdilution method. [ Results] Combined applications of imipenem and caftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox to E. coli ATCC25922 revealed synergistic effects. [ Ceedusion] Combined applications of imipenem and ceftriaxone sodium, imipenem and cefotaxime sodium, amikacin and maquinox greatly reduced drug dosa,qe, imDroved the druq effect, and provided theoretical support for clinical medicine.
文摘[Objective] The paper was to investigate in vitro antibacterial effect of alkaline hydrogen water on Escherichia coli,Salmonella,Pseudomonas aeruginosa and Staphylococcus aureus.[Method] With Cortex cinnamomi extract（1 g/m L） and pure water as the control,the minimal inhibitory concentrations（MIC） against four kinds of common pathogenic microorganisms were tested through microdilution method.[Result] When the alkaline hydrogen water was diluted to 1/8 times of the original concentration,it had significant antibacterial effects on four kinds of common mi-croorganisms with the concentration of 1.5 ×10^5 CFU/m L,which had equivalent effect with C.cinnamomi extract group.[Conclusion]The alkaline hydrogen water has remarkable antibacterial effects on the four kinds of common microorganisms,which may provide a new important way for pre-venting disease occurrence and reducing the harms of pathogenic microorganisms.
基金supported by the Special Fund Project for the Institute Science and Technology Development and Demostration Extention of Henan Provincial Academy of Argricultural Sciences(Research of Zoonotic Small Animal Diseases)the Project for the 2012 Annual"University Students'Innovation Training Program",Southwest University for Nationalities(201210656017)the Special Fund Project for the Central University Basic Scientific Research Fund,Southwest University for Nationalities(11NZYTD02)
文摘[ Objective] This paper aimed to understand drug resistance of Escherichia coli isolated from pets in Guangzhou. I Method ] Broth microdilution method was used to determine the minimal inhibitory concentration （MIC） of ceftiofur, enrofloxacin and other 11 kinds of antibiotics for antimicrobial agent susceptibility testing of 120 strains of clinical E. coli and the experimental data were processed by WHONET 5.4 software. Based on the results of drug resistance pattern analysis, it helped to analyze and study the resistance mechanism. EResultl Clinical E. coli isolated from pets showed a different drug resistance to the 13 kinds of veterinary clinical antibiotics, and the different sources of E. coli also showed a different drug resistance pattern.[Cenclmion] The study provided a theoretical basis for the clinical use of drugs and druq resistance surveillance.
文摘Mycobacteria constitute vast population of bacteria that are found in animals, plants and outer environments. Tuberculosis mycobacteria are a group that causes very dangerous diseases for human and animals. Nontuberculous mycobacteria are mainly environmental and are pathogenic in certain circumstances. There are reports of finding mycobacteria in plant tissues, which can be effective to survey in case of different infectious disease issues. In a previous study, we found mycobacteria strains in alfalfa vascular tissues and identified them to species level using 16S rRNA gene sequence analysis, causing some symptoms in plant tissues and aerial parts. As these rapidly growing mycobacteria (RGM) have the potential to cause opportunistic infections in human tissues, one of the most important issues for dealing with these agents is to find the best and most effective drug to treat them. Here, we conducted some assays to investigate the MIC of 7 antibiotics and two antibacterial agents against eight Mycobacterium frederiksbergense alfalfa isolated strains, in order to find the susceptible and resistant ones. We performed susceptibility testing based on broth microdilution method using Mueller hinton broth as the medium used. Results were different among the strains and different resistant and susceptible reactions were observed among different strains against each drug tested, but ethambutol resulted in similar high MIC for all of them. This variability could be attributed to many factors, such as plant tissue composition and developmental stage from which the strains have been isolated, existence and nature of drug targets and other factors such as test conditions and environmental causes. These results can bring us some insights into design and develop new drugs for treating these kinds of organisms, based on the variations in susceptibility reactions and the plant composition effect on them.
基金Supported by National Natural Science Foundation of China(82073624)Hangzhou Medical and Health Technology Project(A20230270).
文摘Introduction:Nocardia species are found worldwide in soil rich in organic matter and can cause nocardiosis in humans.Trimethoprimsulfamethoxazole has long been the first-line treatment for Nocardia infections;however,resistance to this therapy has recently been reported.Methods:Sixty-three clinical Nocardia isolates collected in China were tested against 32 antimicrobial agents using the broth microdilution method.Phylogenetic analysis of the 16S rRNA gene was performed to identify the species.Results:Three sequences from samples collected in Hainan Province did not match any known Nocardia species,suggesting significant genetic diversity among Nocardia isolates.Nocardia strains generally exhibited high resistance to clarithromycin,clindamycin,and isoniazid.Clinical and reference strains of N.farcinica and N.otitidiscaviarum were susceptible to amikacin and linezolid.Amoxicillin-clavulanate and imipenem were effective against all clinical and reference strains of N.farcinica,whereas gentamicin was effective against all clinical and reference strains of N.otitidiscaviarum.Conclusions:Linezolid and amikacin were the most consistently active drugs among the analyzed species.Variability of antimicrobial susceptibility was observed among clinical isolates of the same species and between clinical and reference isolates of the same species.Overall,this study highlights the need for better assessment of the burden of nocardiosis in China and for continuous monitoring of antimicrobial resistance among Nocardia isolates.
文摘To performance susceptibility testing of antifungal agents Due to the increasing number of resistant strains, susceptibility testing of antifungal agents is gaining importance Methods We compared the results of standard macrotube dilution reference method with two different microdilution methods, as well as the disc diffusion method in order to test the susceptibility of 150 Candida strains to fluconazole Results Overall correlation between microdilution and macrodilution methods was 86% It was 91% between the Minimal Inhibitory Concentrations obtained from macrodilution and disc diffusion zone diameters Conclusion The disc diffusion test was evaluated as a low-cost, reproducible, and efficient way of assessing the in vitro susceptibility of Candida strains to fluconazole
