Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms i...Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms in Zhejiang Province,China,were investigated.A total of 215 isolates were identified as Escherichia coli(64.65%),Klebsiella pneumoniae(12.09%),Proteus mirabilis(10.23%),Salmonella(8.84%),and Enterobacter cloacae(4.19%).Meanwhile,all isolates were resistant to at least two antibiotics.Most isolates carried tet(A)(85.12%),blaTEM(78.60%)and sul1(67.44%)resistance genes.Gene co-occurrence analysis showed that the resistance genes were associated with IS26 and integrons.A conjugative IncFII plasmid pSDM004 containing all the above MGEs was detected in Proteus mirabilis isolate SDM004.This isolate was resistant to 18 antibiotics and carried the blaNDM-5 gene.MGEs,especially plasmids,are the primary antibiotic resistance gene transmission route in duck farms.These findings provide a theoretical basis for the rational use of antibiotics in farms which are substantial for evaluating public health and food safety.展开更多
Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, hos...Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors.展开更多
Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH)...Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH),Kuala Lumpur.Methods:The ARP and presence of the pvl gene were determined for 209 S.aureus isolates from clinical specimens.Of these,123 were methicillin-susceptible S.aureus(MSSA)isolates and 86 were MRSA isolates.All MRSA isolates were characterized using SCCmec typing and spa typing.Descriptive analysis was performed to compare the demographic data with the phenotypic and genotypic variables of the S.aureus isolates.Results:No vancomycin-intermediate and-resistant S.aureus(VISA and VRSA,respectively)were detected among the study isolates.The MSSA isolates showed low resistance rates to all tested antibiotics,were commonly invasive(28/42,66.7%),and mostly harboured pvl(35/42,83.3%).Meanwhile,MRSA isolates showed high resistance to penicillin(86/86,100%),ampicillin(86/86,100%),sulbactam/ampicillin(86/86,100%),cefuroxime(81/86,94.19%),cefoperazone(76/86,88.37%),azithromycin(56/86,65.12%),and erythromycin(54/86,62.79%).The majority of MRSA isolates were of SCCmec type IVh(65/86,75.58%),spa type t032(55/85,63.95%),and grouped into spaCC-t022(66/85,77.65%).The t032 type was found to be associated with resistance traits to azithromycin and erythromycin(P<0.05).We also found several spa types that are typically associated with hospital-,community-,and livestock-associated MRSA co-existing in our MRSA population.Conclusions:This study reflected the consistent absence of VISA and VRSA and corroborated the clonal shifting of MRSA isolates in the Malaysian MRSA isolates.展开更多
Helicobacter pylori(H.pylori)is a Gram-negative bacterium that mainly colonizes the stomach and duodenum,and it can cause gastrointestinal diseases such as gastric inflammation,peptic ulcer and gastric cancer,and erad...Helicobacter pylori(H.pylori)is a Gram-negative bacterium that mainly colonizes the stomach and duodenum,and it can cause gastrointestinal diseases such as gastric inflammation,peptic ulcer and gastric cancer,and eradication of H.pylori can effectively stop the occurrence and development of gastrointestinal diseases.Antibiotics are one of the main drugs used to treat H.pylori.Due to the long-term application of antibiotics,the resistance rate of H.pylori to antibiotics increases year by year,which greatly reduces the eradication rate of H.pylori and increases the difficulty of re-treatment and the economic burden of patients.In this paper,we will review three aspects of H.pylori resistance status,resistance mechanism and treatment to provide reference for the progress of H.pylori resistance research and its treatment strategy.展开更多
Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an incr...Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an increase in mortality as well as the cost of treatment. The present study aims to contribute to the fight against antibiotic resistance of enterobacteria. Methods: This is a prospective study from January to December, 2021 in the Microbiology laboratory of the General Reference Hospital (GRH) of Niamey including 3369 urine samples. The antibiotic resistance of enterobacteria was determined using the Viteck-2 method. Results: At least 280 strains of Enterobacteriaceae were isolated from the patient’s urine. Among these strains, Escherichia coli was the most predominant (74.64%), followed by Klebsiella pneumoniae (16.07%) and Enterobacter cloacae (7.14%) and other enterobacteria 2.15%. These Enterobacteriaceae are more common in community patients than in hospitalized patients. The average age of patients is 52 years and the age group most affected by these enterobacteria is 46 - 60 years (23.33%). The female sex is the most affected sex with (51.07%) against (48.97%) for the male sex with 1.04 as sex ratio. The hospitalization departments most affected by these enterobacteria are Nephrology (29.23%) and Endocrinology (21.54%). Up to 75% of the Enterobacteriaceae isolates show high resistance to ampicillin, amoxicillin-clavulanic acid, ticarcillin, piperacillin-tazobactam, cefoxitin, cefixime, ceftazidime, ceftriaxone, cotrimoxazole, nalidixic acid and ofloxacin. Conclusion: The high rate of antibiotic resistance among enterobacteria in urine is of concern. Only a few Enterobacteriaceae show low resistance to ertapenem, imipenem, amikacin, gentamicin, fosfomycin and nitrofurantoin. Therefore, these antibiotics are recommended as first line treatment for urinary tract infections.展开更多
This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and...This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .展开更多
In Togo, despite the government’s efforts, food requirements in terms of animal proteins are not covered by national production and are subject to huge imports of meat products. However, the hygienic quality of these...In Togo, despite the government’s efforts, food requirements in terms of animal proteins are not covered by national production and are subject to huge imports of meat products. However, the hygienic quality of these imports is not guaranteed for the consumer. The aim of this study was to estimate the frequency of unhygienically unsatisfactory imported poultry and to determine the antibiotic resistance profile of Salmonella spp. strains. A total of 285 samples of imported poultry, including 55 chicken thighs, 10 chicken backbones, 25 chicken wings, 5 whole chickens, 30 sausages, 35 chicken forequarters, 95 chicken drumsticks and 30 guinea fowl wings, were analyzed using standard AFNOR routine methods. The following germs were tested: Total Aerobic Mesophilic Flora (TAMF), Anaerobic-Sulfite-Reducing (ASR), Escherichia coli, Staphylococcus aureus and Salmonella spp. Antibiotic susceptibility testing was carried out on Salmonella spp. strains isolated using the agar disk diffusion method (CA-SFM). Results showed 100% compliance for TAMF, coagulase-positive Staphylococci and Escherichia coli. On the other hand, 3.84% and 2.46% non-compliance were recorded for ASR and Salmonella respectively. Non-compliance with hygiene rules is generally thought to be the cause of meat contamination. Seven 7 strains of Salmonella were isolated, 5 of which were of the OMA serogroup, and the other two of the OMB and HMB groups. Antibiotic susceptibility tests revealed resistance to certain beta-lactam antibiotics and quinolones, in particular: cefalexin (28.57%), cefoxitin (14.28%), cefuroxime (28.57%), ceftazidime (28.57%), ceftriaxone (28.57%) and nalidixic acid (28.57%). This result may be explained by the uncontrolled use of B-lactam and quinolone antibiotics in poultry farming. As Salmonella spp. is a pathogenic enteric bacterium that causes food-borne illness in humans, resistance to third-generation cephalosporins remains a major public health problem.展开更多
The Bacteroides species are important micro-organisms, both in the normal physiology of the intestines and as frequent opportunistic anaerobic pathogens, with a deeply-rooted phylogenetic origin endowing them with som...The Bacteroides species are important micro-organisms, both in the normal physiology of the intestines and as frequent opportunistic anaerobic pathogens, with a deeply-rooted phylogenetic origin endowing them with some interesting biological features. Their prevalence in anaerobic clinical specimens is around 60%-80%, and they display the most numerous and highest rates of antibiotic resistance among all pathogenic anaerobes. In these antibiotic resistance mechanisms there is a noteworthy role for the insertion sequence(IS) elements, which are usually regarded as representatives of ‘selfish' genes; the IS elements of Bacteroides are usually capable of up-regulating the antibiotic resistance genes. These include the cep A(penicillin and cephalosporin), cfx A(cephamycin), cfi A(carbapenem), nim(metronidazole) and erm F(clindamycin) resistance genes. This is achieved by outwardoriented promoter sequences on the ISs. Although some representatives are well characterized, e.g., the resistance gene-IS element pairs in certain resistant strains, open questions remain in this field concerning a better understanding of the molecular biology of theantibiotic resistance mechanisms of Bacteroides, which will have clinical implications.展开更多
Objective:To investigate the resistance profiles to antimicrobial agents of wound-isolated Pseudomonas(P.)aeruginosa among Chinese burn patients.Methods:Electronic databases and manual search were used to identify eli...Objective:To investigate the resistance profiles to antimicrobial agents of wound-isolated Pseudomonas(P.)aeruginosa among Chinese burn patients.Methods:Electronic databases and manual search were used to identify eligible studies published since 2010.The objectives were pooled resistance rates for eleven common antimicrobial agents,estimated by a random-effects model.Subgroup analyses were conducted by stratifying the studies into three four-year periods based on year of isolation.Results:A total of 35 studies were included.Gentamicin had the highest pooled resistance rate(56%,95%CI 48%-64%),while meropenem had the lowest pooled resistance rate(29%,95%CI 20%-40%).There was an increasing trend of resistance to common antimicrobial agents of wound-isolated P.aeruginosa over a span of twelve years(2009-2020).There remained the highest risk of gentamicin resistance over time in China.Subgroup analyses indicated significantly higher resistances to ceftazidime and levofloxacin from 2017 to 2020.Conclusions:Enhanced resistance to common antimicrobial agents in wound-isolated P.aeruginosa presents a challenge in burn wound management in China's Mainland.Effective stewardship programs should be established based on corresponding resistance profiles,thereby optimizing treatment options for hospitalized burn patients.展开更多
Objective Aeromonas has recently been recognized as an emerging human pathogen.Aeromonasassociated diarrhea is a phenomenon occurring worldwide.This study was designed to determine the prevalence,genetic diversity,ant...Objective Aeromonas has recently been recognized as an emerging human pathogen.Aeromonasassociated diarrhea is a phenomenon occurring worldwide.This study was designed to determine the prevalence,genetic diversity,antibiotic resistance,and pathogenicity of Aeromonas strains isolated from food products in Shanghai.Methods Aeromonas isolates(n=79)collected from food samples were analyzed using concatenated gyrB-cpn60 sequencing.The antibiotic resistance of these isolates was determined using antimicrobial susceptibility testing.Pathogenicity was assessed usingβ-hemolytic,extracellular protease,virulence gene detection,C.elegans liquid toxicity(LT),and cytotoxicity assays.Results Eight different species were identified among the 79 isolates.The most prevalent Aeromonas species were A.veronii[62(78.5%)],A.caviae[6(7.6%)],A.dhakensis[3(3.8%)],and A.salmonicida[3(3.8%)].The Aeromonas isolates were divided into 73 sequence types(STs),of which 65 were novel.The isolates were hemolytic(45.6%)and protease-positive(81.0%).The most prevalent virulence genes were act(73.4%),fla(69.6%),aexT(36.7%),and ascV(30.4%).The results of C.elegans LT and cytotoxicity assays revealed that A.dhakensis and A.hydrophila were more virulent than A.veronii,A.caviae,and A.bivalvium.Antibiotic resistance genes[tetE,blaTEM,tetA,qnrS,aac(6)-Ib,mcr-1,and mcr-3]were detected in the isolates.The multidrug-resistance rate of the Aeromonas isolates was 11.4%,and 93.7%of the Aeromonas isolates were resistant to cefazolin.Conclusion The taxonomy,antibiotic resistance,and pathogenicity of different Aeromonas species varied.The Aeromonas isolates A.dhakensis and A.hydrophila were highly pathogenic,indicating that food-derived Aeromonas isolates are potential risks for public health and food safety.The monitoring of food quality and safety will result in better prevention and treatment strategies to control diarrhea illnesses in China.展开更多
AIM: To study antibiotic resistance patterns and susceptibility to eye antiseptic picloxydine of conjunctival flora in patients undergoing intravitreal injections(IVIs).METHODS: Conjunctival swabs were taken in 4 grou...AIM: To study antibiotic resistance patterns and susceptibility to eye antiseptic picloxydine of conjunctival flora in patients undergoing intravitreal injections(IVIs).METHODS: Conjunctival swabs were taken in 4 groups of patients, 20 patients in each group(n=80): without IVIs and ophthalmic operations in history(group N1;control group);with the first IVI and antibiotic eye drops Tobrex applied 3 d before IVI and 5 d after it(group N2);with 20 or more IVIs and repeated courses of antibiotic eye drops(group N3);with the first IVI and antiseptic eye drops Vitabact(picloxydine) applied 3 d before IVI and 5 d after it(group N4). In groups N2 and N4 swabs were taken at baseline and after the treatment. Efficacy of picloxydine in inhibition of growth of conjunctival isolates susceptible and resistant to antibiotic was studied in vitro. Minimal inhibition concentrations(MIC) were determined with microdilution test.RESULTS: Two of the three patients who had to undergo the IVI procedure showed conjunctiva bacterial contamination. Along with few Staphylococcus aureus and Gram-negative isolates susceptible to most antibiotics, the majority(71%-77%) of causative agents were coagulase-negative Staphylococci(Co NS), 40%-50% of which were multidrug resistant(MDR). Eye disinfection in the operating room and peri-injection courses of Tobrex or Vitabact resulted in total elimination of isolates found at baseline. However, in 10% and 20% of patients, respectively, recolonization of the conjunctiva with differing strains occurred. In patients with repeated IVI and Tobrex/Maxitrol treatment, the conjunctival flora showed high resistance rates: 90% of Co NS were MDR. In the in vitro study, picloxydine showed bactericidal effect against Staphylococci isolates both antibiotic resistant and susceptible with MIC≥13.56 μg/m L. Incubation of bacteria for 15 min in Vitabact eye drops, commercially available form of picloxydine, 434 μg/m L, showed total loss of colony forming units of all tested isolates including Pseudomonas aeruginosa. CONCLUSION: The confirmed efficacy of eye antiseptic picloxydine against conjunctival bacterial isolates and the presence of its commercial form, 0.05% eye drops, convenient for use by patients before and after injection, make this eye antiseptic promising for prophylaxis of IVIassociated infectious complications.展开更多
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> The increasing phenome...<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> The increasing phenomenon of bacterial resistance to antibiotics is a real public health problem. The main causes are poor management of hygiene and water quality, but also the use of antibiotics without precaution. The objective of this study was to isolate and determine the antibiotic resistance profile of the different bacteria found in the main hospitals and bacteriology laboratories in Gabon. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> 6034 samples were taken from hospitals in seven main cities of Gabon, and analyzed according to the usual techniques. The pathogenic strains were identified by Matrix-Assisted Laser Desorption Ionization-Time Of Flight Mass Spectrometry. Antimicrobial susceptibility testing was performed by the agar disc diffusion method, according to the Antibiogram Committee of the French Society for Microbiology guidelines. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">974 pathogenic bacterial strains were found, including 890/974 (91</span><span style="font-family:Verdana;">.4%) Gram-negative bacilli. The systematic antimicrobial suscepti</span><span style="font-family:Verdana;">bility testings identified 160/974 (16.4%) multi-resistant strains. </span><i><span style="font-family:Verdana;">Escherichia coli</span></i><span style="font-family:Verdana;"> was t</span><span style="font-family:Verdana;">he most represented species. 12.5%</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">25% of </span><i><span style="font-family:Verdana;">Escherichia coli</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Klebsiel</span></i></span><i><span style="font-family:Verdana;">la pneumoniae</span></i><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Enterobacter cloacae</span></i><span style="font-family:Verdana;">, and </span><i><span style="font-family:Verdana;">Citrobacter sedlakii</span></i><span style="font-family:Verdana;"> strains were resistant to amoxicillin + clavulanic acid, third and fourth generation cephalosporins. Aminoglycoside resistance rates of 8.5%</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">19% were also noted. 4.5% to 25% of the bacteria found were resistant to quinolones and cotrimoxazole. Resistance rates to carbapenems ranged from 1% to 10.5%. 16% of </span><i><span style="font-family:Verdana;">Staphylococcus aureus</span></i><span style="font-family:Verdana;"> were methicillin-resistant (MRSA). Rates of extended spectr</span><span style="font-family:Verdana;">um beta-lactamase-producing enterobacteriaceae (ESBL-PE) ran</span><span style="font-family:Verdana;">ged from 2.5% to 25%. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> This study showed an increasing evolution of bacteri</span><span style="font-family:Verdana;">al resistance to antibiotics that </span></span><span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> spreading throughout Gabon. Th</span><span style="font-family:Verdana;">is constitutes a threat to the health of Gabonese population.展开更多
Foot infections resulting from biofilm producers and multi-drug resistant organisms is one of the most important complications of diabetes mellitus, as it can impede the wound healing process. This study was carried o...Foot infections resulting from biofilm producers and multi-drug resistant organisms is one of the most important complications of diabetes mellitus, as it can impede the wound healing process. This study was carried out in order to determine the antibiotic resistance pattern and the biofilm production in diabetic foot ulcers isolates. Clinical samples were collected from patients suffering from diabetic foot ulcers by using sterile swabs. Antibiotic susceptibility test was done using disk diffusion method on Mueller Hinton Agar. Biofilm formation was assessed by Crystal Violet Staining Method. <i>Staphylococcus aureus</i> isolates were resistant to ofloxacin (83.3%), ciprofloxacin (75.0%), trimethoprim-sulphamethoxazole (75.0%), and gentamicin (58.8%) but very sensitive to oxacillin (100.0%) and vancomycin (91.7%). <i>Pseudomonas aeruginosa</i> isolates showed resistance to the commonly used antibiotics such as ofloxacin, cefotaxime, ampicillin (81.8%), ceftazidime and imipenem (72.7%). The majority of bacteria studied were biofilm producers. This study showed that bacteria isolated from diabetic foot ulcers were biofilm producers and presented resistance to commonly used antibiotics. Knowledge on antibiotic sensitivity pattern and biofilm phenotype of the isolates will be helpful in determining the drugs for the treatment of diabetic ulcers.展开更多
The study is to identify trends and levels of antibiotic resistance of some common Gram-negative strains over time. The samples were collected from Vietnam Military Hospital 103 between 2014 and 2019. A total of 405 &...The study is to identify trends and levels of antibiotic resistance of some common Gram-negative strains over time. The samples were collected from Vietnam Military Hospital 103 between 2014 and 2019. A total of 405 <i>Acinetobacter baumannii</i>., 528 <i>Pseudomonas aeruginosa</i>, 741 <i>Escherichia coli</i>, and 352 <i>Klebsiella pneumoniae</i> strains were identified and antimicrobial susceptibility was by Vitek system and Etest method. The multi-drug resistance (MDR) was major proportion of four common bacteria. In particular, there is a tendency to shift from MDR to Extended drug resistance (XDR) or possibly Pan drug resistant (pPDR). <i>A. baumannii</i> had the highest level of antibiotic resistance, namely, carbapenem (61.5% - 82.5%) and cephalosporin (72.7% - 88.7%). <i>P. aeruginosa</i> resisted most of commonly antibiotics, ranging from 50% to 70%. <i>E. coli</i> had a high resistance with antibiotics like ampicillin (87.2% - 97.6%) and the 3rd generation cephalosporins (up to 79.6%). <i>K. pneumoniae</i> resisted carbapenem from 14.7% to 44.4%, and other antibiotics with the higher rate of 40%. The collected data will be a prerequisite for further studies on mechanisms and factors related to antibiotic resistant bacteria, in order to find out a rational and effective using strategy of antibiotics.展开更多
Antibiotic wastewater contains a variety of pollutant stressors that can induce and promote antibiotic resistance(AR)when released into the environment.Although these substances are mostly in concentrations lower than...Antibiotic wastewater contains a variety of pollutant stressors that can induce and promote antibiotic resistance(AR)when released into the environment.Although these substances are mostly in concentrations lower than those known to induce AR individually,it is possible that antibiotic wastewater discharge might still promote the AR transmission risk via additive or synergistic effects.However,the comprehensive effect of antibiotic wastewater on AR development has rarely been evaluated,and its treatment efficiency remains unknown.Here,samples were collected from different stages of a cephalosporin production wastewater treatment plant,and the potential AR induction effect of their chemical mixtures was explored through the exposure of the antibiotic-sensitive Escherichia coli K12 strain.Incubation with raw cephalosporin production wastewater significantly promoted mutation rates(3.6×10^(3)-9.3×10^(3)-fold)and minimum inhibition concentrations(6.0-6.7-fold)of E.coli against ampicillin and chloramphenicol.This may be attributed to the inhibition effect and oxidative stress of cephalosporin wastewater on E.coli.The AR induction effect of cephalosporin wastewater decreased after the coagulation sedimentation treatment and was completely removed after the full treatment process.A Pearson correlation analysis revealed that the reduction in the AR induction effect had a strong positive correlation with the removal of organics and biological toxicity.This indicates that the antibiotic wastewater treatment had a collaborative processing effect of conventional pollutants,toxicity,and the AR induction effect.This study illustrates the potential AR transmission risk of antibiotic wastewater and highlights the need for its adequate treatment.展开更多
This study explored the combined effects of Bacillus subtilis inoculation with biochar on the evolution of bacterial communities,antibiotic resistance genes(ARGs),and mobile genetic elements(MGEs)during the composting...This study explored the combined effects of Bacillus subtilis inoculation with biochar on the evolution of bacterial communities,antibiotic resistance genes(ARGs),and mobile genetic elements(MGEs)during the composting of chicken manure.The results showed that B.subtilis inoculation combined with biochar increased bacterial abundance and diversity as well as prolonged the compost thermophilic period.Promoted organic matter biodegradation and facilitated the organic waste compost humification process,reduced the proliferation of ARGs by altering the bacterial composition.Firmicutes and Actinobacteriota were the main resistant bacteria related to ARGs and MGEs.The decrease in ARGs and MGEs was associated with the reduction in the abundance of related host bacteria.Compost inoculation with B.subtilis and the addition of biochar could promote nutrient transformation,reduce the increase in ARGs and MGEs,and increase the abundance of beneficial soil taxa.展开更多
Antibiotic fermentation residue(AFR)is nutrient-rich solid waste generated from fermentative antibiotic production process.It is demonstrated that AFR contains high-concentration of remaining antibiotics,and thus may ...Antibiotic fermentation residue(AFR)is nutrient-rich solid waste generated from fermentative antibiotic production process.It is demonstrated that AFR contains high-concentration of remaining antibiotics,and thus may promote antibiotic resistance development in receiving environment or feeding farmed animals.However,the dominate microorganisms and antibiotic resistance genes(ARGs)in AFRs have not been adequately explored,hampering understanding on the potential antibiotic resistance risk development caused by AFRs.Herein,seven kinds of representative AFRs along their production,storage,and treatment processes were collected,and multiple methods including amplicon sequencing,metagenomic sequencing,and bioinformatic approaches were adopted to explore the biological characteristics of AFRs.As expected,antibiotic fermentation producer was found as the predominant species in raw AFRs,which were collected at the outlet of fermentation tanks.However,except for producer species,more environment-derived species persisted in stored AFRs,which were temporarily stored at a semi-open space.Lactobacillus genus,classified as Firmicutes phylum and Bacilli class,became predominant bacterial taxa in stored AFRs,which might attribute to its tolerance to high concentration of antibiotics.Results from metagenomic sequencing together with assembly and binning approaches showed that these newly-colonizing species(e.g.,Lactobacillus genus)tended to carry ARGs conferring resistance to the remaining antibiotic.However,after thermal treatment,remaining antibiotic could be efficiently removed from AFRs,and microorganisms together with DNA could be strongly destroyed.In sum,the main risk from the AFRs was the remaining antibiotic,while environment-derived bacteria which tolerate extreme environment,survived in ARFs with high content antibiotics,and may carry ARGs.Thus,hydrothermal or other harmless treatment technologies are recommended to remove antibiotic content and inactivate bacteria before recycling of AFRs in pharmaceutical industry.展开更多
Despite coastal mudflats serving as essential ecological zones interconnecting terrestrial/freshwater and marine systems,little is known about the profiles of antibiotic resistance genes(ARGs)in this area.In this stud...Despite coastal mudflats serving as essential ecological zones interconnecting terrestrial/freshwater and marine systems,little is known about the profiles of antibiotic resistance genes(ARGs)in this area.In this study,characteristics of typical ARGs,involving both intracellular(iARGs)and extracellular ARGs(eARGs)at different physical states,were explored in over 1000 km of coastal mudflats in Eastern China.Results indicated the presence of iARGs and eARGs at states of both freely present or attached by particles.The abundance of eARGs was significantly higher than that of iARGs(87.3%vs 12.7%),and their dominance was more significant than those in other habitats(52.7%-76.3%).ARG abundance,especially for eARGs,showed an increasing trend(p<0.05)from southern(Nantong)to northern(Lianyungang)coastalmudflats.Higher salinity facilitated the transformation from iARGs to eARGs,and smaller soil particle size was conducive to the persistence of eARGs in northern coastal mudflats.This study addresses the neglected function of coastal mudflats as eARGs reservoirs.展开更多
Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dis...Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these coselection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance(MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.展开更多
Comprehensive studies of the effects of various physical and chemical variables(including heavymetals),antibiotics,and microorganisms in the environment on antibiotic resistance genes are rare.We collected sediment sa...Comprehensive studies of the effects of various physical and chemical variables(including heavymetals),antibiotics,and microorganisms in the environment on antibiotic resistance genes are rare.We collected sediment samples from the Shatian Lake aquaculture area and surrounding lakes and rivers located in Shanghai,China.The spatial distribution of sediment ARGs was assessed by metagenomic analysis that revealed 26 ARG types(510 subtypes),dominated by Multidrug,β-lactam,Aminoglycoside,Glycopeptides,Fluoroquinolone,and Tetracyline.Redundancy discriminant analysis indicated that antibiotics(SAs and MLs)in the aqueous environment and sediment along with water TN and TP were the key variables affecting the abundance distribution of total ARGs.However,the main environmental drivers and key influences differed among the different ARGs.For total ARGs,the environmental subtypes affecting their structural composition and distribution characteristics were mainly antibiotic residues.Procrustes analysis showed a significant correlation between ARGs and microbial communities in the sediment in the survey area.Network analysis revealed that most of the target ARGs were significantly and positively correlated with microorganisms,and a small number of ARGs(e.g.,rpoB,mdtC,and efpA)were highly significantly and positively correlated with microorganisms(e.g.,Knoellia,Tetrasphaera,and Gem-matirosa).Potential hosts for the major ARGs included Actinobacteria,Proteobacteria,and Gemmatimonadetes.Our study provides new insight and a comprehensive assessment of the distribution and abundance of ARGs and the drivers of ARG occurrence and transmission.展开更多
基金supported by the National Natural Science Foundation of China(32172188)Science and Technology Cooperation Project of ZheJiang Province(2023SNJF058-3)。
文摘Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms in Zhejiang Province,China,were investigated.A total of 215 isolates were identified as Escherichia coli(64.65%),Klebsiella pneumoniae(12.09%),Proteus mirabilis(10.23%),Salmonella(8.84%),and Enterobacter cloacae(4.19%).Meanwhile,all isolates were resistant to at least two antibiotics.Most isolates carried tet(A)(85.12%),blaTEM(78.60%)and sul1(67.44%)resistance genes.Gene co-occurrence analysis showed that the resistance genes were associated with IS26 and integrons.A conjugative IncFII plasmid pSDM004 containing all the above MGEs was detected in Proteus mirabilis isolate SDM004.This isolate was resistant to 18 antibiotics and carried the blaNDM-5 gene.MGEs,especially plasmids,are the primary antibiotic resistance gene transmission route in duck farms.These findings provide a theoretical basis for the rational use of antibiotics in farms which are substantial for evaluating public health and food safety.
文摘Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors.
基金The study was funded by the UPNM Short Term Grant (UPNM/2019/GPJP/SP/1).
文摘Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH),Kuala Lumpur.Methods:The ARP and presence of the pvl gene were determined for 209 S.aureus isolates from clinical specimens.Of these,123 were methicillin-susceptible S.aureus(MSSA)isolates and 86 were MRSA isolates.All MRSA isolates were characterized using SCCmec typing and spa typing.Descriptive analysis was performed to compare the demographic data with the phenotypic and genotypic variables of the S.aureus isolates.Results:No vancomycin-intermediate and-resistant S.aureus(VISA and VRSA,respectively)were detected among the study isolates.The MSSA isolates showed low resistance rates to all tested antibiotics,were commonly invasive(28/42,66.7%),and mostly harboured pvl(35/42,83.3%).Meanwhile,MRSA isolates showed high resistance to penicillin(86/86,100%),ampicillin(86/86,100%),sulbactam/ampicillin(86/86,100%),cefuroxime(81/86,94.19%),cefoperazone(76/86,88.37%),azithromycin(56/86,65.12%),and erythromycin(54/86,62.79%).The majority of MRSA isolates were of SCCmec type IVh(65/86,75.58%),spa type t032(55/85,63.95%),and grouped into spaCC-t022(66/85,77.65%).The t032 type was found to be associated with resistance traits to azithromycin and erythromycin(P<0.05).We also found several spa types that are typically associated with hospital-,community-,and livestock-associated MRSA co-existing in our MRSA population.Conclusions:This study reflected the consistent absence of VISA and VRSA and corroborated the clonal shifting of MRSA isolates in the Malaysian MRSA isolates.
基金Construction project of Hainan Medical Center (No.2021818)Innovative Research Projects for Graduate Students of Hainan Medical College (No.HYYS2021B14)。
文摘Helicobacter pylori(H.pylori)is a Gram-negative bacterium that mainly colonizes the stomach and duodenum,and it can cause gastrointestinal diseases such as gastric inflammation,peptic ulcer and gastric cancer,and eradication of H.pylori can effectively stop the occurrence and development of gastrointestinal diseases.Antibiotics are one of the main drugs used to treat H.pylori.Due to the long-term application of antibiotics,the resistance rate of H.pylori to antibiotics increases year by year,which greatly reduces the eradication rate of H.pylori and increases the difficulty of re-treatment and the economic burden of patients.In this paper,we will review three aspects of H.pylori resistance status,resistance mechanism and treatment to provide reference for the progress of H.pylori resistance research and its treatment strategy.
文摘Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an increase in mortality as well as the cost of treatment. The present study aims to contribute to the fight against antibiotic resistance of enterobacteria. Methods: This is a prospective study from January to December, 2021 in the Microbiology laboratory of the General Reference Hospital (GRH) of Niamey including 3369 urine samples. The antibiotic resistance of enterobacteria was determined using the Viteck-2 method. Results: At least 280 strains of Enterobacteriaceae were isolated from the patient’s urine. Among these strains, Escherichia coli was the most predominant (74.64%), followed by Klebsiella pneumoniae (16.07%) and Enterobacter cloacae (7.14%) and other enterobacteria 2.15%. These Enterobacteriaceae are more common in community patients than in hospitalized patients. The average age of patients is 52 years and the age group most affected by these enterobacteria is 46 - 60 years (23.33%). The female sex is the most affected sex with (51.07%) against (48.97%) for the male sex with 1.04 as sex ratio. The hospitalization departments most affected by these enterobacteria are Nephrology (29.23%) and Endocrinology (21.54%). Up to 75% of the Enterobacteriaceae isolates show high resistance to ampicillin, amoxicillin-clavulanic acid, ticarcillin, piperacillin-tazobactam, cefoxitin, cefixime, ceftazidime, ceftriaxone, cotrimoxazole, nalidixic acid and ofloxacin. Conclusion: The high rate of antibiotic resistance among enterobacteria in urine is of concern. Only a few Enterobacteriaceae show low resistance to ertapenem, imipenem, amikacin, gentamicin, fosfomycin and nitrofurantoin. Therefore, these antibiotics are recommended as first line treatment for urinary tract infections.
文摘This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .
文摘In Togo, despite the government’s efforts, food requirements in terms of animal proteins are not covered by national production and are subject to huge imports of meat products. However, the hygienic quality of these imports is not guaranteed for the consumer. The aim of this study was to estimate the frequency of unhygienically unsatisfactory imported poultry and to determine the antibiotic resistance profile of Salmonella spp. strains. A total of 285 samples of imported poultry, including 55 chicken thighs, 10 chicken backbones, 25 chicken wings, 5 whole chickens, 30 sausages, 35 chicken forequarters, 95 chicken drumsticks and 30 guinea fowl wings, were analyzed using standard AFNOR routine methods. The following germs were tested: Total Aerobic Mesophilic Flora (TAMF), Anaerobic-Sulfite-Reducing (ASR), Escherichia coli, Staphylococcus aureus and Salmonella spp. Antibiotic susceptibility testing was carried out on Salmonella spp. strains isolated using the agar disk diffusion method (CA-SFM). Results showed 100% compliance for TAMF, coagulase-positive Staphylococci and Escherichia coli. On the other hand, 3.84% and 2.46% non-compliance were recorded for ASR and Salmonella respectively. Non-compliance with hygiene rules is generally thought to be the cause of meat contamination. Seven 7 strains of Salmonella were isolated, 5 of which were of the OMA serogroup, and the other two of the OMB and HMB groups. Antibiotic susceptibility tests revealed resistance to certain beta-lactam antibiotics and quinolones, in particular: cefalexin (28.57%), cefoxitin (14.28%), cefuroxime (28.57%), ceftazidime (28.57%), ceftriaxone (28.57%) and nalidixic acid (28.57%). This result may be explained by the uncontrolled use of B-lactam and quinolone antibiotics in poultry farming. As Salmonella spp. is a pathogenic enteric bacterium that causes food-borne illness in humans, resistance to third-generation cephalosporins remains a major public health problem.
基金Supported by The Center of Excellence at the University of Szeged(TáMOP-421B)to József Sóki.
文摘The Bacteroides species are important micro-organisms, both in the normal physiology of the intestines and as frequent opportunistic anaerobic pathogens, with a deeply-rooted phylogenetic origin endowing them with some interesting biological features. Their prevalence in anaerobic clinical specimens is around 60%-80%, and they display the most numerous and highest rates of antibiotic resistance among all pathogenic anaerobes. In these antibiotic resistance mechanisms there is a noteworthy role for the insertion sequence(IS) elements, which are usually regarded as representatives of ‘selfish' genes; the IS elements of Bacteroides are usually capable of up-regulating the antibiotic resistance genes. These include the cep A(penicillin and cephalosporin), cfx A(cephamycin), cfi A(carbapenem), nim(metronidazole) and erm F(clindamycin) resistance genes. This is achieved by outwardoriented promoter sequences on the ISs. Although some representatives are well characterized, e.g., the resistance gene-IS element pairs in certain resistant strains, open questions remain in this field concerning a better understanding of the molecular biology of theantibiotic resistance mechanisms of Bacteroides, which will have clinical implications.
文摘Objective:To investigate the resistance profiles to antimicrobial agents of wound-isolated Pseudomonas(P.)aeruginosa among Chinese burn patients.Methods:Electronic databases and manual search were used to identify eligible studies published since 2010.The objectives were pooled resistance rates for eleven common antimicrobial agents,estimated by a random-effects model.Subgroup analyses were conducted by stratifying the studies into three four-year periods based on year of isolation.Results:A total of 35 studies were included.Gentamicin had the highest pooled resistance rate(56%,95%CI 48%-64%),while meropenem had the lowest pooled resistance rate(29%,95%CI 20%-40%).There was an increasing trend of resistance to common antimicrobial agents of wound-isolated P.aeruginosa over a span of twelve years(2009-2020).There remained the highest risk of gentamicin resistance over time in China.Subgroup analyses indicated significantly higher resistances to ceftazidime and levofloxacin from 2017 to 2020.Conclusions:Enhanced resistance to common antimicrobial agents in wound-isolated P.aeruginosa presents a challenge in burn wound management in China's Mainland.Effective stewardship programs should be established based on corresponding resistance profiles,thereby optimizing treatment options for hospitalized burn patients.
基金supported by the National Key Research and Development Program of China[grant number 2018YFC1603804]。
文摘Objective Aeromonas has recently been recognized as an emerging human pathogen.Aeromonasassociated diarrhea is a phenomenon occurring worldwide.This study was designed to determine the prevalence,genetic diversity,antibiotic resistance,and pathogenicity of Aeromonas strains isolated from food products in Shanghai.Methods Aeromonas isolates(n=79)collected from food samples were analyzed using concatenated gyrB-cpn60 sequencing.The antibiotic resistance of these isolates was determined using antimicrobial susceptibility testing.Pathogenicity was assessed usingβ-hemolytic,extracellular protease,virulence gene detection,C.elegans liquid toxicity(LT),and cytotoxicity assays.Results Eight different species were identified among the 79 isolates.The most prevalent Aeromonas species were A.veronii[62(78.5%)],A.caviae[6(7.6%)],A.dhakensis[3(3.8%)],and A.salmonicida[3(3.8%)].The Aeromonas isolates were divided into 73 sequence types(STs),of which 65 were novel.The isolates were hemolytic(45.6%)and protease-positive(81.0%).The most prevalent virulence genes were act(73.4%),fla(69.6%),aexT(36.7%),and ascV(30.4%).The results of C.elegans LT and cytotoxicity assays revealed that A.dhakensis and A.hydrophila were more virulent than A.veronii,A.caviae,and A.bivalvium.Antibiotic resistance genes[tetE,blaTEM,tetA,qnrS,aac(6)-Ib,mcr-1,and mcr-3]were detected in the isolates.The multidrug-resistance rate of the Aeromonas isolates was 11.4%,and 93.7%of the Aeromonas isolates were resistant to cefazolin.Conclusion The taxonomy,antibiotic resistance,and pathogenicity of different Aeromonas species varied.The Aeromonas isolates A.dhakensis and A.hydrophila were highly pathogenic,indicating that food-derived Aeromonas isolates are potential risks for public health and food safety.The monitoring of food quality and safety will result in better prevention and treatment strategies to control diarrhea illnesses in China.
文摘AIM: To study antibiotic resistance patterns and susceptibility to eye antiseptic picloxydine of conjunctival flora in patients undergoing intravitreal injections(IVIs).METHODS: Conjunctival swabs were taken in 4 groups of patients, 20 patients in each group(n=80): without IVIs and ophthalmic operations in history(group N1;control group);with the first IVI and antibiotic eye drops Tobrex applied 3 d before IVI and 5 d after it(group N2);with 20 or more IVIs and repeated courses of antibiotic eye drops(group N3);with the first IVI and antiseptic eye drops Vitabact(picloxydine) applied 3 d before IVI and 5 d after it(group N4). In groups N2 and N4 swabs were taken at baseline and after the treatment. Efficacy of picloxydine in inhibition of growth of conjunctival isolates susceptible and resistant to antibiotic was studied in vitro. Minimal inhibition concentrations(MIC) were determined with microdilution test.RESULTS: Two of the three patients who had to undergo the IVI procedure showed conjunctiva bacterial contamination. Along with few Staphylococcus aureus and Gram-negative isolates susceptible to most antibiotics, the majority(71%-77%) of causative agents were coagulase-negative Staphylococci(Co NS), 40%-50% of which were multidrug resistant(MDR). Eye disinfection in the operating room and peri-injection courses of Tobrex or Vitabact resulted in total elimination of isolates found at baseline. However, in 10% and 20% of patients, respectively, recolonization of the conjunctiva with differing strains occurred. In patients with repeated IVI and Tobrex/Maxitrol treatment, the conjunctival flora showed high resistance rates: 90% of Co NS were MDR. In the in vitro study, picloxydine showed bactericidal effect against Staphylococci isolates both antibiotic resistant and susceptible with MIC≥13.56 μg/m L. Incubation of bacteria for 15 min in Vitabact eye drops, commercially available form of picloxydine, 434 μg/m L, showed total loss of colony forming units of all tested isolates including Pseudomonas aeruginosa. CONCLUSION: The confirmed efficacy of eye antiseptic picloxydine against conjunctival bacterial isolates and the presence of its commercial form, 0.05% eye drops, convenient for use by patients before and after injection, make this eye antiseptic promising for prophylaxis of IVIassociated infectious complications.
文摘<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> The increasing phenomenon of bacterial resistance to antibiotics is a real public health problem. The main causes are poor management of hygiene and water quality, but also the use of antibiotics without precaution. The objective of this study was to isolate and determine the antibiotic resistance profile of the different bacteria found in the main hospitals and bacteriology laboratories in Gabon. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> 6034 samples were taken from hospitals in seven main cities of Gabon, and analyzed according to the usual techniques. The pathogenic strains were identified by Matrix-Assisted Laser Desorption Ionization-Time Of Flight Mass Spectrometry. Antimicrobial susceptibility testing was performed by the agar disc diffusion method, according to the Antibiogram Committee of the French Society for Microbiology guidelines. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">974 pathogenic bacterial strains were found, including 890/974 (91</span><span style="font-family:Verdana;">.4%) Gram-negative bacilli. The systematic antimicrobial suscepti</span><span style="font-family:Verdana;">bility testings identified 160/974 (16.4%) multi-resistant strains. </span><i><span style="font-family:Verdana;">Escherichia coli</span></i><span style="font-family:Verdana;"> was t</span><span style="font-family:Verdana;">he most represented species. 12.5%</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">25% of </span><i><span style="font-family:Verdana;">Escherichia coli</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Klebsiel</span></i></span><i><span style="font-family:Verdana;">la pneumoniae</span></i><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Enterobacter cloacae</span></i><span style="font-family:Verdana;">, and </span><i><span style="font-family:Verdana;">Citrobacter sedlakii</span></i><span style="font-family:Verdana;"> strains were resistant to amoxicillin + clavulanic acid, third and fourth generation cephalosporins. Aminoglycoside resistance rates of 8.5%</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">19% were also noted. 4.5% to 25% of the bacteria found were resistant to quinolones and cotrimoxazole. Resistance rates to carbapenems ranged from 1% to 10.5%. 16% of </span><i><span style="font-family:Verdana;">Staphylococcus aureus</span></i><span style="font-family:Verdana;"> were methicillin-resistant (MRSA). Rates of extended spectr</span><span style="font-family:Verdana;">um beta-lactamase-producing enterobacteriaceae (ESBL-PE) ran</span><span style="font-family:Verdana;">ged from 2.5% to 25%. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> This study showed an increasing evolution of bacteri</span><span style="font-family:Verdana;">al resistance to antibiotics that </span></span><span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> spreading throughout Gabon. Th</span><span style="font-family:Verdana;">is constitutes a threat to the health of Gabonese population.
文摘Foot infections resulting from biofilm producers and multi-drug resistant organisms is one of the most important complications of diabetes mellitus, as it can impede the wound healing process. This study was carried out in order to determine the antibiotic resistance pattern and the biofilm production in diabetic foot ulcers isolates. Clinical samples were collected from patients suffering from diabetic foot ulcers by using sterile swabs. Antibiotic susceptibility test was done using disk diffusion method on Mueller Hinton Agar. Biofilm formation was assessed by Crystal Violet Staining Method. <i>Staphylococcus aureus</i> isolates were resistant to ofloxacin (83.3%), ciprofloxacin (75.0%), trimethoprim-sulphamethoxazole (75.0%), and gentamicin (58.8%) but very sensitive to oxacillin (100.0%) and vancomycin (91.7%). <i>Pseudomonas aeruginosa</i> isolates showed resistance to the commonly used antibiotics such as ofloxacin, cefotaxime, ampicillin (81.8%), ceftazidime and imipenem (72.7%). The majority of bacteria studied were biofilm producers. This study showed that bacteria isolated from diabetic foot ulcers were biofilm producers and presented resistance to commonly used antibiotics. Knowledge on antibiotic sensitivity pattern and biofilm phenotype of the isolates will be helpful in determining the drugs for the treatment of diabetic ulcers.
文摘The study is to identify trends and levels of antibiotic resistance of some common Gram-negative strains over time. The samples were collected from Vietnam Military Hospital 103 between 2014 and 2019. A total of 405 <i>Acinetobacter baumannii</i>., 528 <i>Pseudomonas aeruginosa</i>, 741 <i>Escherichia coli</i>, and 352 <i>Klebsiella pneumoniae</i> strains were identified and antimicrobial susceptibility was by Vitek system and Etest method. The multi-drug resistance (MDR) was major proportion of four common bacteria. In particular, there is a tendency to shift from MDR to Extended drug resistance (XDR) or possibly Pan drug resistant (pPDR). <i>A. baumannii</i> had the highest level of antibiotic resistance, namely, carbapenem (61.5% - 82.5%) and cephalosporin (72.7% - 88.7%). <i>P. aeruginosa</i> resisted most of commonly antibiotics, ranging from 50% to 70%. <i>E. coli</i> had a high resistance with antibiotics like ampicillin (87.2% - 97.6%) and the 3rd generation cephalosporins (up to 79.6%). <i>K. pneumoniae</i> resisted carbapenem from 14.7% to 44.4%, and other antibiotics with the higher rate of 40%. The collected data will be a prerequisite for further studies on mechanisms and factors related to antibiotic resistant bacteria, in order to find out a rational and effective using strategy of antibiotics.
基金supported by the National Key Research and Development Program of China(No.2017ZX07103-007)。
文摘Antibiotic wastewater contains a variety of pollutant stressors that can induce and promote antibiotic resistance(AR)when released into the environment.Although these substances are mostly in concentrations lower than those known to induce AR individually,it is possible that antibiotic wastewater discharge might still promote the AR transmission risk via additive or synergistic effects.However,the comprehensive effect of antibiotic wastewater on AR development has rarely been evaluated,and its treatment efficiency remains unknown.Here,samples were collected from different stages of a cephalosporin production wastewater treatment plant,and the potential AR induction effect of their chemical mixtures was explored through the exposure of the antibiotic-sensitive Escherichia coli K12 strain.Incubation with raw cephalosporin production wastewater significantly promoted mutation rates(3.6×10^(3)-9.3×10^(3)-fold)and minimum inhibition concentrations(6.0-6.7-fold)of E.coli against ampicillin and chloramphenicol.This may be attributed to the inhibition effect and oxidative stress of cephalosporin wastewater on E.coli.The AR induction effect of cephalosporin wastewater decreased after the coagulation sedimentation treatment and was completely removed after the full treatment process.A Pearson correlation analysis revealed that the reduction in the AR induction effect had a strong positive correlation with the removal of organics and biological toxicity.This indicates that the antibiotic wastewater treatment had a collaborative processing effect of conventional pollutants,toxicity,and the AR induction effect.This study illustrates the potential AR transmission risk of antibiotic wastewater and highlights the need for its adequate treatment.
基金supported by the Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University (No.CXZX2020073A)Project of Fujian Provincial Department of Science and Technology,China (No.2022N5007)。
文摘This study explored the combined effects of Bacillus subtilis inoculation with biochar on the evolution of bacterial communities,antibiotic resistance genes(ARGs),and mobile genetic elements(MGEs)during the composting of chicken manure.The results showed that B.subtilis inoculation combined with biochar increased bacterial abundance and diversity as well as prolonged the compost thermophilic period.Promoted organic matter biodegradation and facilitated the organic waste compost humification process,reduced the proliferation of ARGs by altering the bacterial composition.Firmicutes and Actinobacteriota were the main resistant bacteria related to ARGs and MGEs.The decrease in ARGs and MGEs was associated with the reduction in the abundance of related host bacteria.Compost inoculation with B.subtilis and the addition of biochar could promote nutrient transformation,reduce the increase in ARGs and MGEs,and increase the abundance of beneficial soil taxa.
基金supported by the National Natural Science Foundation of China (No.32141002)。
文摘Antibiotic fermentation residue(AFR)is nutrient-rich solid waste generated from fermentative antibiotic production process.It is demonstrated that AFR contains high-concentration of remaining antibiotics,and thus may promote antibiotic resistance development in receiving environment or feeding farmed animals.However,the dominate microorganisms and antibiotic resistance genes(ARGs)in AFRs have not been adequately explored,hampering understanding on the potential antibiotic resistance risk development caused by AFRs.Herein,seven kinds of representative AFRs along their production,storage,and treatment processes were collected,and multiple methods including amplicon sequencing,metagenomic sequencing,and bioinformatic approaches were adopted to explore the biological characteristics of AFRs.As expected,antibiotic fermentation producer was found as the predominant species in raw AFRs,which were collected at the outlet of fermentation tanks.However,except for producer species,more environment-derived species persisted in stored AFRs,which were temporarily stored at a semi-open space.Lactobacillus genus,classified as Firmicutes phylum and Bacilli class,became predominant bacterial taxa in stored AFRs,which might attribute to its tolerance to high concentration of antibiotics.Results from metagenomic sequencing together with assembly and binning approaches showed that these newly-colonizing species(e.g.,Lactobacillus genus)tended to carry ARGs conferring resistance to the remaining antibiotic.However,after thermal treatment,remaining antibiotic could be efficiently removed from AFRs,and microorganisms together with DNA could be strongly destroyed.In sum,the main risk from the AFRs was the remaining antibiotic,while environment-derived bacteria which tolerate extreme environment,survived in ARFs with high content antibiotics,and may carry ARGs.Thus,hydrothermal or other harmless treatment technologies are recommended to remove antibiotic content and inactivate bacteria before recycling of AFRs in pharmaceutical industry.
基金This study was supported by the National Natural Science Foundation of China(No.42177348)the Natural Science Foundation of Jiangsu Province(No.BK20201367)China Postdoctoral Science Foundation(No.2021M701663).
文摘Despite coastal mudflats serving as essential ecological zones interconnecting terrestrial/freshwater and marine systems,little is known about the profiles of antibiotic resistance genes(ARGs)in this area.In this study,characteristics of typical ARGs,involving both intracellular(iARGs)and extracellular ARGs(eARGs)at different physical states,were explored in over 1000 km of coastal mudflats in Eastern China.Results indicated the presence of iARGs and eARGs at states of both freely present or attached by particles.The abundance of eARGs was significantly higher than that of iARGs(87.3%vs 12.7%),and their dominance was more significant than those in other habitats(52.7%-76.3%).ARG abundance,especially for eARGs,showed an increasing trend(p<0.05)from southern(Nantong)to northern(Lianyungang)coastalmudflats.Higher salinity facilitated the transformation from iARGs to eARGs,and smaller soil particle size was conducive to the persistence of eARGs in northern coastal mudflats.This study addresses the neglected function of coastal mudflats as eARGs reservoirs.
基金supported by the National Natural Science Foundation of China (Nos. 41991332, 41977323 and 42090063)。
文摘Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these coselection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance(MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.
基金This work was supported by the Chinese Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07207002-03)the Science and Technology Commission of Shanghai Municipality(Nos.19050501900 and 19DZ1204504)EJ was supported by TüBITAK program BIDEB2232(No.118C250).We would also like to express our deep thanks to Anne Mette Poulsen from Aarhus University for her English assistance.
文摘Comprehensive studies of the effects of various physical and chemical variables(including heavymetals),antibiotics,and microorganisms in the environment on antibiotic resistance genes are rare.We collected sediment samples from the Shatian Lake aquaculture area and surrounding lakes and rivers located in Shanghai,China.The spatial distribution of sediment ARGs was assessed by metagenomic analysis that revealed 26 ARG types(510 subtypes),dominated by Multidrug,β-lactam,Aminoglycoside,Glycopeptides,Fluoroquinolone,and Tetracyline.Redundancy discriminant analysis indicated that antibiotics(SAs and MLs)in the aqueous environment and sediment along with water TN and TP were the key variables affecting the abundance distribution of total ARGs.However,the main environmental drivers and key influences differed among the different ARGs.For total ARGs,the environmental subtypes affecting their structural composition and distribution characteristics were mainly antibiotic residues.Procrustes analysis showed a significant correlation between ARGs and microbial communities in the sediment in the survey area.Network analysis revealed that most of the target ARGs were significantly and positively correlated with microorganisms,and a small number of ARGs(e.g.,rpoB,mdtC,and efpA)were highly significantly and positively correlated with microorganisms(e.g.,Knoellia,Tetrasphaera,and Gem-matirosa).Potential hosts for the major ARGs included Actinobacteria,Proteobacteria,and Gemmatimonadetes.Our study provides new insight and a comprehensive assessment of the distribution and abundance of ARGs and the drivers of ARG occurrence and transmission.