BACKGROUND In the absence of effective antimicrobials,transplant surgery is not viable,and antirejection immunosuppressants cannot be administered,as resistant infections compromise the life-saving goal of organ trans...BACKGROUND In the absence of effective antimicrobials,transplant surgery is not viable,and antirejection immunosuppressants cannot be administered,as resistant infections compromise the life-saving goal of organ transplantation.AIM To evaluate the efficacy of antimicrobials in preventing resistance in solid organ transplant recipients.METHODS A systematic review was conducted using a search methodology consistent with the preferred reporting items for systematic reviews and meta-analyses.This review included randomized clinical trials that evaluated the efficacy of antimicrobial agents(prophylactic or therapeutic)aimed at preventing antimicrobial resistance.The search strategy involved analyzing multiple databases,including PubMed/MEDLINE,Web of Science,Embase,Scopus,and SciELO,as well as examining gray literature sources on Google Scholar.A comprehensive electronic database search was conducted from the databases’inception until May 2024,with no language restrictions.RESULTS After the final phase of the eligibility assessment,this systematic review ultimate-ly included 7 articles.A total of 2318 patients were studied.The most studied microorganisms were cytomegalovirus,although vancomycinresistant enterococci,Clostridioides difficile,and multidrug-resistant Enterobacterales were also analyzed.The antimicrobials used in the interventions were mainly maribavir,valganciclovir,gancic-lovir,and colistin-neomycin.Of concern,all clinical trials showed significant proportions of resistant microorga-nisms after the interventions,with no statistically significant differences between the groups(mean resistance 13.47%vs 14.39%),except for two studies that demonstrated greater efficacy of maribavir and valganciclovir(mean resistance 22.2%vs 41.1%in the control group;P<0.05).The total reported deaths in three clinical trials were 75,and there were 24 graft rejections in two studies.CONCLUSION All clinical trials reported significant proportions of antimicrobial-resistant microorganisms following interventions.More high-quality randomized clinical trials are needed to corroborate these results.展开更多
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"></span><b> </b><span style="font-family:Verdan...<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"></span><b> </b><span style="font-family:Verdana;">Antibiotic resistance is putting the commercial poultry production systems across the globe at risk of losses due to the failure of treatments for animals and human health which has been associated with overuse and misuse of antibiotics in poultry farming. One possible approach to the resistance problem is ensuring adequate knowledge, attitudes, and practices on antimicrobial use by farmers on commercial production systems across the globe are applied. Therefore, the current study was carried out to determine factors that could promote antimicrobial use in commercial poultry production systems of Kiambu County, Kenya. </span><b><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">Methods:</span></b><span></span></b><span style="font-family:Verdana;"> A descriptive cross-sectional survey was conducted on commercial poultry production systems of Kiambu County to determine the level of knowledge, attitudes, and practices on antimicrobial use. One hundred and fifty-six (n = 156) semi-structured questionnaires imprinted in a mobile Open data kit were administered to capture the level of knowledge, attitudes, and practices on antimicrobial usage in commercial poultry production systems of Kiambu County. </span><b><b><span style="font-family:Verdana;">Results:</span></b><span></span></b><span style="font-family:Verdana;"> Out of the 156 commercial poultry farmers who participated in this study, females accounted for (64%) with 51% of them keeping layers between 50 - 500 birds as medium scale farmers. In the study</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> most of the farmers were 45 years and above (61%) and they had obtained a secondary level of education (34%). We further noted that 67% of the farmers obtain antibiotics through self-prescription/personal experience. Additional lack of veterinary officers (77%) and consultation services (72%) was also mentioned as</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">key challenges in poultry production. The majority of the respondents (63%), indicated Tetracycline as the most commonly used antibiotic in their farms, with the most preferred subtypes of tetracycline and Amoxicillin being Oxytetracyclines (85%) and Amoxi (88%) respectively. Nearness to veterinary services significantly (P < 0.05) contributed to the use of antibiotics agents. Additionally, the area of residence, type of production, number of years in farming, and average number of birds kept also significantly (P < 0.05) influenced the level of knowledge and practice on antimicrobial usage. </span><b><b><span style="font-family:Verdana;">Conclusion:</span></b><span></span></b> <span style="font-family:Verdana;">Generally, the level of knowledge and practice on antibiotic use among commercial poultry farmers in Kiambu County is still lacking. This was witne</span></span><span style="font-family:Verdana;">ssed</span><span style="font-family:Verdana;"> with continued use of antibiotics without a prescription from veterinary/</span><span style="font-family:Verdana;">livestock extension offices, which is inconsis</span><span style="font-family:Verdana;">tent with the general recommendation on antimicrobial stewardship. Therefore, the current research calls for intervention measures such as extensive education to farmers on the rat</span><span style="font-family:Verdana;">ional use of antimicrobial agents in commercial poultry disease management, observance of withdraw</span><span style="font-family:Verdana;">al</span><span style="font-family:Verdana;"> periods, and the impacts of residues on public health.</span>展开更多
Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial infections.Despite its importance,the characterization of ARGs and microbiom...Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial infections.Despite its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or regions.Here,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and Europe.Results showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(P<0.05).ANT(6)-Ib,APH(3')-IIIa,and tet(40)were identified as shared core ARGs between the two pig populations.Furthermore,the core ARGs identified in pig populations were correlated with those found in human populations within the same geographical regions.Lactobacillus and Prevotella were identified as the dominant genera in the core microbiomes of Chinese and European pigs,respectively.Forty ARG markers and 43 biomarkers were able to differentiate between the Chinese and European pig manure samples with accuracies of 100%and 98.7%,respectively.Indicators for assessing ARG contamination in Chinese and European pigs also achieved high accuracy(r=0.72-0.88).Escherichia flexneri in both Chinese and European pig populations carried between 21 and 37 ARGs.The results of this study emphasize the importance of global collaboration in reducing antimicrobial resistance risk and provide validated indicators for evaluating the risk of ARG contamination in pig farms.展开更多
AIM: To investigate the efficacy of extended antimicrobial prophylaxis (EAP) after gastrectomy by systematic review of literature and meta-analysis. METHODS: Electronic databases of PubMed, Embase, CINAHL, the Cochran...AIM: To investigate the efficacy of extended antimicrobial prophylaxis (EAP) after gastrectomy by systematic review of literature and meta-analysis. METHODS: Electronic databases of PubMed, Embase, CINAHL, the Cochrane Database of Systematic Reviews, the Cochrane Controlled Trials Register and the China National Knowledge Infrastructure were searched systematically from January 1980 to October 2012. Strict literature retrieval and data extraction were carried out independently by two reviewers and meta-analyses were conducted using RevMan 5.0.2 with statistics tools risk ratios (RRs) and intention-to-treat analyses to evaluate the items of total complications, surgical site infection, incision infection, organ (or space) infection, remote site infection, anastomotic leakage (or dehiscence) and mortality. Fixed model or random model was selected accordingly and forest plot was conducted to display RR. Likewise, Cochrane Risk of Bias Tool was applied to evaluate the quality of randomized controlled trials (RCTs) included in this meta-analysis. RESULTS: A total of 1095 patients with gastric cancer were enrolled in four RCTs. No statistically significant differences were detected between EAP and intraoperative antimicrobial prophylaxis (IAP) in total complications (RR of 0.86, 95%CI: 0.63-1.16, P = 0.32), surgical site infection (RR of 1.97, 95%CI: 0.86-4.48, P = 0.11), incision infection (RR of 4.92, 95%CI: 0.58-41.66, P = 0.14), organ or space infection (RR of 1.55, 95%CI: 0.61-3.89, P = 0.36), anastomotic leakage or dehiscence (RR of 3.85, 95%CI: 0.64-23.17, P = 0.14) and mortality (RR of 1.14, 95%CI: 0.10-13.12; P = 0.92). Likewise, multiple-dose antimicrobial prophylaxis showed no difference compared with single-dose antimicrobial prophylaxis in surgical site infection (RR of 1.10, 95%CI: 0.62-1.93, P = 0.75). Nevertheless, EAP showed a decreased remote site infection rate compared with IAP alone (RR of 0.54, 95%CI: 0.34-0.86, P = 0.01), which is the only significant finding. Unfortunately, EAP did not decrease the incidence of surgical site infections after gastrectomy; likewise, multipledose antimicrobial prophylaxis failed to decrease the incidence of surgical site infection compared with single-dose antimicrobial prophylaxis. CONCLUSION: We recommend that EAP should not be used routinely after gastrectomy until more high-quality RCTs are available.展开更多
[Objective] The study was to explore whether antimicrobial activity of the antimicrobial peptides extracted from immunized Tenebrio molitor varied with different pathogens as inducers.[Method]By inducing T.molitor hun...[Objective] The study was to explore whether antimicrobial activity of the antimicrobial peptides extracted from immunized Tenebrio molitor varied with different pathogens as inducers.[Method]By inducing T.molitor hungry larvaes to generate immune response via feeding with bacteria and with fungi or actinomycete post to pricking,the antimicrobial peptides extracts were obtained by grinding and centrifuging the cultures.Its antimicrobial activity against 26 pathogens was measured by bacteriostatic ring,and evaluated by trisection to four types and inhibitory spectrum.[Result]Both the antimicrobial activity and antimicrobial spectrum of the antimicrobial peptides extracts varied remarkably among different pathogens as inducers.[Conclusion]Bio-control used strains have obvious advantage in inducing the insect to express body fluid immunity material-antimicrobial peptides.展开更多
Objective This study aimed to evaluate the genetic diversity,virulence,and antimicrobial resistance of Aeromonas isolates from clinical patients,tap water systems,and food.Methods Ninety Aeromonas isolates were obtain...Objective This study aimed to evaluate the genetic diversity,virulence,and antimicrobial resistance of Aeromonas isolates from clinical patients,tap water systems,and food.Methods Ninety Aeromonas isolates were obtained from Ma’anshan,Anhui province,China,and subjected to multi-locus sequence typing(MLST)with six housekeeping genes.Their taxonomy was investigated using concatenated gyr B-cpn60 sequences,while their resistance to 12 antibiotics was evaluated.Ten putative virulence factors and several resistance genes were identified by PCR and sequencing.Results The 90 Aeromonas isolates were divided into 84 sequence types,80 of which were novel,indicating high genetic diversity.The Aeromonas isolates were classified into eight different species.PCR assays identified virulence genes in the isolates,with the enterotoxin and hemolysin genes act,aer A,alt,and ast found in 47(52.2%),13(14.4%),22(24.4%),and 12(13.3%)of the isolates,respectively.The majority of the isolates(≥90%)were susceptible to aztreonam,imipenem,cefepime,chloramphenicol,gentamicin,tetracycline,and ciprofloxacin.However,several resistance genes were detected in the isolates,as well as a new mcr-3 variant.Conclusions Sequence type,virulence properties,and antibiotic resistance vary in Aeromonas isolates from clinical patients,tap water systems,and food.展开更多
Nanomaterials have been found increasing applications in the food sector.Nanostructured antimicrobials can be incorporated either to food matrix of food packaging or to provide extended safety and quality.However,the ...Nanomaterials have been found increasing applications in the food sector.Nanostructured antimicrobials can be incorporated either to food matrix of food packaging or to provide extended safety and quality.However,the interactions and effects of nanomaterials with biological systems are still poorly understood.Nanoparticles can enter the organism by oral,dermal and inhalation routes and distributed to different tissues by the circulatory system.Increasing evidence indicate that targeting to specific tissues,cellular uptake and intracellular fate of nanoparticles are strongly influenced by size,shape and surface properties.The specific characteristics of nanomaterials are also determinant for their toxicity in higher organisms.The dose,exposure time and administration route are important aspects influencing toxicity of nanoparticles as well.Both in vitro and in vivo evaluation studies on different types of nanostructures have providing information to support a better understanding about the interactions of nanoscale materials with biological systems.展开更多
A simple route to synthesize novel fluorinated fused hetero-polycyclic nitrogen systems containing a pyrazolotriazine moiety (5,8,11) have been deduced from cyclization of 2-aminothiocarbonyl-5-arylidene-3-phenyl-1,2,...A simple route to synthesize novel fluorinated fused hetero-polycyclic nitrogen systems containing a pyrazolotriazine moiety (5,8,11) have been deduced from cyclization of 2-aminothiocarbonyl-5-arylidene-3-phenyl-1,2,4-triazin-6(1H)one (2) with diethoxy-phosphine, diethyl carbonate and/or diethyl oxalate in boil THF followed by cyclo condensation with aryl sulfonic acid hydrazide in EtOH/piperidine and finally fluorination with trifluoroethyl acetate. Structures of the products have been established from their elemental analysis and spectral measurements. The antimicrobial activity of the targets has also been evaluated.展开更多
There has been a rising interest in using natural antimicrobial compounds in food industry due to current trend of giving value to natural and renewable resources. These antimicrobials provide new modalities to ensure...There has been a rising interest in using natural antimicrobial compounds in food industry due to current trend of giving value to natural and renewable resources. These antimicrobials provide new modalities to ensure microbial safety and extend the shelf-life of foodstuffs. Natural antimicrobials can be directly added into the food, but several efforts have been made to find alternative solutions to the aim of avoiding undesirable inactivation. Some different ways such as, dipping, spraying, and coating treatment of food are currently applied to product before packaging considered as valid options. The present paper aims to review the use of natural compounds to control microbiological and physicochemical shelf life of major food categories such as, meat, fish, dairy-based products, fruit and vegetables, and cereal-based products.展开更多
A laboratory information system (LIS) established in a microbiology department has the potential to play an important role in the quality of microbiology data such as culture of blood, urine, stool, pus swab samples e...A laboratory information system (LIS) established in a microbiology department has the potential to play an important role in the quality of microbiology data such as culture of blood, urine, stool, pus swab samples etc. Such data could be effectively utilised to measure the burden of antimicrobial resistance among patients presented to various hospitals and clinics with an episode of an infectious illness of bacterial origin. A variety of clinical and epidemiological investigations are conducted using culture data and the presence of an electronic system such as LIS enhances such investigations and improves the reliability of measures of antimicrobial resistance owing to improved data quality as well as completeness of data gathered as opposed to paper based system. Therefore to improve surveillance of antimicrobial resistance in South Africa, there is a need to reinforce the functionality of the LIS in both public and private microbiology laboratories as this will help to improve internal quality control methodologies.展开更多
Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poult...Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and control.Antibiotics have been used not only for the treatment and prevention of such diseases,but also for growth promotion.Consequently,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the environment.To break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’demands.However,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome.Various Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,E.coli)and Gram-positive(Enterococcus spp.,Staphylococcus spp.and C.perfringens)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised chickens.In this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.展开更多
Endophytic fungi(EF)colonize plant tissues without causing damage;this relationship brings benefits to both,including a greater resistance to environmental stresses,but the influence of genotypes and culture system in...Endophytic fungi(EF)colonize plant tissues without causing damage;this relationship brings benefits to both,including a greater resistance to environmental stresses,but the influence of genotypes and culture system in endophytic community is still unraveled.Thus,this work aimed to study EF from Sorghum bicolor and correlate to its genotypes submitted to different culture systems;their potential to produce antimicrobial compounds was also evaluated.To optimize the production of metabolites,four isolates were submitted to liquid medium and the crude extracts of different culture times were analyzed.EF of leaves of Qualimax and SF15 genotypes were isolated after superficial disinfection.Fungal identification was made using classical taxonomy.As results,the traditional system presented the lowest number EF isolates,while the minimum system showed the highest.The genera Aspergillus,Fusarium,Penicillium,Cladosporium,Curvularia and Syncephalastrum were found;Aspergillus spp.was pointed out as a predominant endophyte of genotype Qualimax.Among the 25 endophytes submitted antimicrobial activity assay in solid medium,21 presented antibacterial activity against at least one bacterium with the highest inhibition zone of 29.3 mm of diameter against Staphylococcus aureus.All EF submitted to liquid medium kept the capacity to produce antibacterial metabolites.In conclusion,regardless of genotype and culture system,sorghum is colonized by different EF,mainly Aspergillus spp.EF from leaves of S.bicolor produce antibacterial compounds and their biotechnological applications can be explored in future.展开更多
<b><span style="font-family:Verdana;">Introduction:</span></b><span style="font-family:""><span style="font-family:Verdana;"> In the last two deca...<b><span style="font-family:Verdana;">Introduction:</span></b><span style="font-family:""><span style="font-family:Verdana;"> In the last two decades, the treatment of enteric infections has been complicated by the emergence of antimicrobial resistant strains. Occurrence of multidrug resistant Extended Spectrum Beta Lactamase (ESBL) producing </span><i><span style="font-family:Verdana;">Enterobactaeraceae</span></i><span style="font-family:Verdana;"> pose</span></span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> the greatest risk to public health by raising morbidity and mortality by six folds in developing countries. The present study aims to determine the antibiotics resistance patterns of selected</span><i><span style="font-family:Verdana;"> Entero</span><span style="font-family:Verdana;">bacteriaceae</span></i><span style="font-family:Verdana;"> isolated from commercial poultry production systems i</span><span style="font-family:Verdana;">n Kiamb</span><span><span style="font-family:Verdana;">u County. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> A laboratory based cross-sectional study was co</span></span><span style="font-family:Verdana;">nducted in six purposively selected Sub-Counties of Kiambu County from October 2020, to February 2021. A total of 437 fecal samples were collected from each household. The antibiotic susceptibility testing using disk diffusion method w</span></span><span style="font-family:Verdana;">as</span><span style="font-family:""><span style="font-family:Verdana;"> used against </span><i><span style="font-family:Verdana;">E.</span></i></span><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">coli</span></i><span style="font-family:""><span style="font-family:Verdana;">;</span><i><span style="font-family:Verdana;"> Salmonella spps.</span></i><span style="font-family:Verdana;">;</span><i><span style="font-family:Verdana;"> Shigella spps.</span></i><span style="font-family:Verdana;">;</span><i> </i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Klebsiella spps. </span></i><span style="font-family:Verdana;">which were isolated and identified th</span></span><span style="font-family:Verdana;">r</span><span style="font-family:""><span style="font-family:Verdana;">ough standard biochemical. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Out of 437 fecal and stool samples collected, 591 isolates were recovered with </span><i><span style="font-family:Verdana;">E.</span></i></span><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">coli</span></i><span style="font-family:""><span style="font-family:Verdana;"> (48.9%) being the most frequently identified, followed by </span><i><span style="font-family:Verdana;">Shigella spps.</span></i><span style="font-family:Verdana;"> (18.8%), </span><i><span style="font-family:Verdana;">Salmonella spps.</span></i><span style="font-family:Verdana;"> (18.3%), and </span><i><span style="font-family:Verdana;">Klebsiella spps.</span></i><span style="font-family:Verdana;"> (14.0%). The study shows there was high prevalence of multiple resistance among isolates especially to Sulfamethoxazole (79%), Trimethoprim (71%), and Tetracyclines (59%), correspondingly. Additionally, the isolates showed </span></span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">highest rate of suscep</span><span style="font-family:Verdana;">tibility against Cefuroxime (94%), Gentamicin (93%), Ceftriaxo</span><span style="font-family:Verdana;">ne (91%), Cefepime (89%), Cefotaxime (85%), Ceftazidime (84%), and Chloramphenicol (77%), respectively. </span><b><span style="font-family:Verdana;">Discussion:</span></b><span style="font-family:Verdana;"> Our study indicates that both fecal and stool materials from commercial poultry and humans can be reservoir of multi-drug resistance enteric’s which can be a potential route</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">of transmission of resistance genes, which pose a great risk to public health of Kiambu Residence.展开更多
Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious d...Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases.展开更多
The world will benefit from more effective antimicrobial agents against oral conditions arising from the actions of biofilm forming bacteria. Also, information is lacking on the oral biofilm-forming bacterial diversit...The world will benefit from more effective antimicrobial agents against oral conditions arising from the actions of biofilm forming bacteria. Also, information is lacking on the oral biofilm-forming bacterial diversity in Southwestern Nigeria. In this study, we isolate and characterize oral biofilm producing bacteria in the oral cavities of schoolchildren in Southwestern Nigeria. We also investigate the antimicrobial properties of Macrosphyra longistyla extracts against the biofilm-formers and the toxicity of potent extracts. Samples were obtained from 109 schoolchildren aged 4 - 14 years from Lagos, Oyo and Osun States. Agar well diffusion technique was used in the antimicrobial susceptibility testing. Toxicity testing was done using brine shrimps (Artemia salina). Biofilm-formers in this study are Klebsiella sp., Streptococcus sp., Staphylococcus sp., and Micrococcus sp. Ethanol leaf extracts had the highest activity against all biofilm-producing bacteria. Ethanol stem bark extract, which elicited activity against Klebsiella only, was found to be less toxic than the ethanol leaf extract. Staphylococcus showed >10 mm susceptibility to the ethanol and aqueous extracts of Macrosphyra longistyla. Streptococcus and Micrococcus were susceptible to the antimicrobial actions of the ethanolic leaf extracts. Although the ethanol extracts of the leaves had lower minimum inhibitory concentrations than the ethanol extracts of the stem bark, toxicity studies showed ethanol extracts of the stem-bark to be more toxic than the ethanol extracts of the leaves. In conclusion, ethanolic extracts of Macrosphyra longistyla show potential as sources of antimicrobials against gram-positive, oral biofilm-forming bacteria.展开更多
Objective: To evaluate the spread of Multidrug-Resistant (MDR) bacterial infections in Bukavu hospitals and test antimicrobial susceptibility patterns of some isolates to usual marketed antibiotics. Methods: The preva...Objective: To evaluate the spread of Multidrug-Resistant (MDR) bacterial infections in Bukavu hospitals and test antimicrobial susceptibility patterns of some isolates to usual marketed antibiotics. Methods: The prevalence of MDR strains was determined by using general antimicrobial susceptibility data collected from 3 hospital laboratories. The susceptibility of some isolates to usual antibiotics was processed by agar diffusion method with standard E. coli ATCC8739 and standard antibiotics discs as controls. The tested antibiotics were ampicillin, ceftriaxone, gentamicin, chloramphenicol and ciprofloxacin. Results: At the 3 hospitals, 758 tests were realized in urine, pus, stool, FCV, blood, LCR, split and FU specimens;46 strains were unidentified and 712 strains were identified. Of 712 identified strains, 223 (31.4%) were MDR or XDR strains including Escherichia coli, Klebsiella pneumoniae, Enterobacter, Proteus mirabilis, Salmonella enterica, Pseudomonas aeruginosa, Citrobacter freundii, Morganella morganii, Enterococcus faecalis and E. faecium, Neisseria gonorrohoae, Staphylococcus aureus, coagulase-negative, staphylococci, Streptococcus pneumoniae and Streptococcus pyogenes. Of the infected patients, 36 (21.5%) children were under 16 years and 188 (78.5%) adults were predominately women (58.5%). The susceptibility test showed that all strains but S. aureus were resistant to ampicillin and amoxicillin and ciprofloxacin. Gentamicin, ceftriaxone, and chloramphenicol remain partially active (27% - 80%) against P. mirabilis, E. coli and P. aeruginosa. The resistance is more likely related to strain mutation than to pharmaceutical quality of the antibiotics prescribed. Conclusion: Both data from hospital laboratories and in vitro post-testing findings confirmed the ongoing elevated prevalence of MDR strains in Bukavu. The causes of antibiotic misuse and socio-economic determinants of the phenomenon of resistance should be scrutinized in order to take adequate strategies in the prospective of establishing an effective control system against this threat to overall health. The results of this work on MDR profiles have various implications for the management of infectious diseases. It provides indicators for the surveillance of antimicrobial resistance, practical guidelines for antibiotic susceptibility testing in biomedical laboratories, and guidance for antibiotic therapy.展开更多
Some bacteria have the ability to co-exist, proliferate and survive in a multicellular community, biofilm. Each participating bacteria can form its colonies and encases itself by a self-produced insoluble extracellula...Some bacteria have the ability to co-exist, proliferate and survive in a multicellular community, biofilm. Each participating bacteria can form its colonies and encases itself by a self-produced insoluble extracellular matrix substance (EPS). Microcolonies within biofilm are held together by interactions and bonding of the substances present in the EPS with their separation from the water channels. Similar to insoluble EPS, bacterial microcolonies release soluble exofactors that have direct impacts on the survivability, growth and antibacterial resistivity of other microcolonies made of single- or multi-species bacteria in the same biofilm. How the exofactors of microcolonies of one-type bacteria impact on microcolonies of other-type bacteria is still unclear. We studied about the role of exofactors released from Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, which are common biofilm-forming pathogenic bacteria. Exofactors facilitate to transform the microenvironment where bacteria can acquire alternative lifestyle with a long survival period and resistivity to certain antimicrobial drugs.展开更多
Piptoporellus baudonii, previously known as Laetiporus baudonii, is an African species that was considered to be a sister species to Laetiporus sulphureus, another European species known for its medicinal value. While...Piptoporellus baudonii, previously known as Laetiporus baudonii, is an African species that was considered to be a sister species to Laetiporus sulphureus, another European species known for its medicinal value. While much is known about the edibility and antimicrobial properties of L. sulphureus, African species like P. baudonii remain understudied. This study investigated the antimicrobial and antioxidant properties of P. baudonii extracts (powder maceration) prepared using ethanol, methanol and water with fractions obtained via differential solubility in hexane, ethyl acetate and n-butanol. Before the antimicrobial analysis, the study material was accurately identified using both morphology and molecular techniques. Antimicrobial activity was tested against fungi, gram-positive, and gram-negative bacteria using a broth serial microdilution method, while antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power FRAP methods. Phylogenetic analysis confirmed the specimen as P. baudonii, with genetic material from Benin grouping it with other P. baudonii from Tanzania and other unknown regions, forming a well-supported clade (100/100). The ethanol (1.71), methanol (2.41) extracts, along with ethyl acetate (1.36), n-butanol (1.18), and hexane (12.91) fractions showed significant antioxidant activity with EC50 values below 20 µg∙mL−1. The highest antimicrobial inhibition was seen in the n-butanol (58%) and ethyl acetate (54%) fractions, followed by ethanol (49%) and hexane (48%). Methanol exhibited the lowest inhibition (46.10%). These values were compared to the standard (Vitamin C). The examined extracts demonstrated high bactericidal properties, with an MBC/MIC ratio (R) of 1 to 4, particularly effective ethyl acetate against Escherichia coli (R = 2) and ethanol extract with strong activity against Enterococcus faecalis (R = 4). Further chemical and cytotoxicity studies are warranted to fully explore the pharmaceutical potential of P. baudonii.展开更多
Objective:To fully understand the overall system and implementation of antimicrobial stewardship(AMS)at different levels in China,an evaluation according to the integrated AMS evaluation tool developed by World Health...Objective:To fully understand the overall system and implementation of antimicrobial stewardship(AMS)at different levels in China,an evaluation according to the integrated AMS evaluation tool developed by World Health Organization(WHO)was conducted.Methods:A comprehensive search on the AMS relevant government policies,regulations,scientific research results,public and social activities was conducted,and the implementation of AMS strategies in national,subnational and hospital level were evaluated by the standards of the WHO.Results:The results shew that the system construction,technical infrastructure and actions of AMS in China at the national level is relatively satisfied,but the AMS system needs to be further strengthened at the subnational and the medical institutional level,especially the integration of multidisciplinary teams and relevant departments;the implementation of professional intervention strategies,national education and publicity,professional education and training are relatively weak.AMS implementation is mainly promoted at the national level,and AMS in primary medical institutions is almost missing.It is necessary to carry out AMS at the provincial level and medical institutions as soon as possible.The focus is to establish a professional AMS team,prepare AMS guideline,implement AMS strategy,raise public awareness and ensure the long‐term and sustainable development of AMS in the country.Conclusion:The Chinese government has established a system for AMS,and implemented a multisectoral coordinative mechanism.However,at the subnational and district levels,an AMS system and practice should be set up soon to promote the rational use of antibiotics.展开更多
BACKGROUND:Prompt pathogen identification can have a substantial impact on the optimization of antimicrobial treatment.The objective of the study was to assess the diagnostic value of next-generation sequencing(NGS)fo...BACKGROUND:Prompt pathogen identification can have a substantial impact on the optimization of antimicrobial treatment.The objective of the study was to assess the diagnostic value of next-generation sequencing(NGS)for identifying pathogen and its clinical impact on antimicrobial intervention in immunocompromised patients with suspected infections.METHODS:This was a retrospective study.Between January and August 2020,47 adult immunocompromised patients underwent NGS testing under the following clinical conditions:1)prolonged fever and negative conventional cultures;2)new-onset fever despite empiric antimicrobial treatment;and 3)afebrile with suspected infections on imaging.Clinical data,including conventional microbial test results and antimicrobial treatment before and after NGS,were collected.Data were analyzed according to documented changes in antimicrobial treatment(escalated,no change,or deescalated)after the NGS results.RESULTS:The median time from hospitalization to NGS sampling was 19 d.Clinically relevant pathogens were detected via NGS in 61.7% of patients(29/47),more than half of whom suffered from fungemia(n=17),resulting in an antimicrobial escalation in 53.2% of patients(25/47)and antimicrobial de-escalation in 0.2% of patients(1/47).Antimicrobial changes were mostly due to the identification of fastidious organisms such as Legionella,Pneumocystis jirovecii,and Candida.In the remaining three cases,NGS detected clinically relevant pathogens also detected by conventional cultures a few days later.The antimicrobial treatment was subsequently adjusted according to the susceptibility test results.Overall,NGS changed antimicrobial management in 55.3%(26/47)of patients,and conventional culture detected clinically relevant pathogens in 14.9% of the patients(7/47).CONCLUSION:With its rapid identification and high sensitivity,NGS could be a promising tool for identifying relevant pathogens and enabling rapid appropriate treatment in immunocompromised patients with suspected infections.展开更多
文摘BACKGROUND In the absence of effective antimicrobials,transplant surgery is not viable,and antirejection immunosuppressants cannot be administered,as resistant infections compromise the life-saving goal of organ transplantation.AIM To evaluate the efficacy of antimicrobials in preventing resistance in solid organ transplant recipients.METHODS A systematic review was conducted using a search methodology consistent with the preferred reporting items for systematic reviews and meta-analyses.This review included randomized clinical trials that evaluated the efficacy of antimicrobial agents(prophylactic or therapeutic)aimed at preventing antimicrobial resistance.The search strategy involved analyzing multiple databases,including PubMed/MEDLINE,Web of Science,Embase,Scopus,and SciELO,as well as examining gray literature sources on Google Scholar.A comprehensive electronic database search was conducted from the databases’inception until May 2024,with no language restrictions.RESULTS After the final phase of the eligibility assessment,this systematic review ultimate-ly included 7 articles.A total of 2318 patients were studied.The most studied microorganisms were cytomegalovirus,although vancomycinresistant enterococci,Clostridioides difficile,and multidrug-resistant Enterobacterales were also analyzed.The antimicrobials used in the interventions were mainly maribavir,valganciclovir,gancic-lovir,and colistin-neomycin.Of concern,all clinical trials showed significant proportions of resistant microorga-nisms after the interventions,with no statistically significant differences between the groups(mean resistance 13.47%vs 14.39%),except for two studies that demonstrated greater efficacy of maribavir and valganciclovir(mean resistance 22.2%vs 41.1%in the control group;P<0.05).The total reported deaths in three clinical trials were 75,and there were 24 graft rejections in two studies.CONCLUSION All clinical trials reported significant proportions of antimicrobial-resistant microorganisms following interventions.More high-quality randomized clinical trials are needed to corroborate these results.
文摘<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"></span><b> </b><span style="font-family:Verdana;">Antibiotic resistance is putting the commercial poultry production systems across the globe at risk of losses due to the failure of treatments for animals and human health which has been associated with overuse and misuse of antibiotics in poultry farming. One possible approach to the resistance problem is ensuring adequate knowledge, attitudes, and practices on antimicrobial use by farmers on commercial production systems across the globe are applied. Therefore, the current study was carried out to determine factors that could promote antimicrobial use in commercial poultry production systems of Kiambu County, Kenya. </span><b><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">Methods:</span></b><span></span></b><span style="font-family:Verdana;"> A descriptive cross-sectional survey was conducted on commercial poultry production systems of Kiambu County to determine the level of knowledge, attitudes, and practices on antimicrobial use. One hundred and fifty-six (n = 156) semi-structured questionnaires imprinted in a mobile Open data kit were administered to capture the level of knowledge, attitudes, and practices on antimicrobial usage in commercial poultry production systems of Kiambu County. </span><b><b><span style="font-family:Verdana;">Results:</span></b><span></span></b><span style="font-family:Verdana;"> Out of the 156 commercial poultry farmers who participated in this study, females accounted for (64%) with 51% of them keeping layers between 50 - 500 birds as medium scale farmers. In the study</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> most of the farmers were 45 years and above (61%) and they had obtained a secondary level of education (34%). We further noted that 67% of the farmers obtain antibiotics through self-prescription/personal experience. Additional lack of veterinary officers (77%) and consultation services (72%) was also mentioned as</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">key challenges in poultry production. The majority of the respondents (63%), indicated Tetracycline as the most commonly used antibiotic in their farms, with the most preferred subtypes of tetracycline and Amoxicillin being Oxytetracyclines (85%) and Amoxi (88%) respectively. Nearness to veterinary services significantly (P < 0.05) contributed to the use of antibiotics agents. Additionally, the area of residence, type of production, number of years in farming, and average number of birds kept also significantly (P < 0.05) influenced the level of knowledge and practice on antimicrobial usage. </span><b><b><span style="font-family:Verdana;">Conclusion:</span></b><span></span></b> <span style="font-family:Verdana;">Generally, the level of knowledge and practice on antibiotic use among commercial poultry farmers in Kiambu County is still lacking. This was witne</span></span><span style="font-family:Verdana;">ssed</span><span style="font-family:Verdana;"> with continued use of antibiotics without a prescription from veterinary/</span><span style="font-family:Verdana;">livestock extension offices, which is inconsis</span><span style="font-family:Verdana;">tent with the general recommendation on antimicrobial stewardship. Therefore, the current research calls for intervention measures such as extensive education to farmers on the rat</span><span style="font-family:Verdana;">ional use of antimicrobial agents in commercial poultry disease management, observance of withdraw</span><span style="font-family:Verdana;">al</span><span style="font-family:Verdana;"> periods, and the impacts of residues on public health.</span>
基金supported by the Foundation for the National Key R&D Program(2022YFD1800400)Innovative Research Groups of the National Natural Science Foundation of China(32121004)Natural Science Foundation of Guangdong Province of China(2021A1515011159)。
文摘Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial infections.Despite its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or regions.Here,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and Europe.Results showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(P<0.05).ANT(6)-Ib,APH(3')-IIIa,and tet(40)were identified as shared core ARGs between the two pig populations.Furthermore,the core ARGs identified in pig populations were correlated with those found in human populations within the same geographical regions.Lactobacillus and Prevotella were identified as the dominant genera in the core microbiomes of Chinese and European pigs,respectively.Forty ARG markers and 43 biomarkers were able to differentiate between the Chinese and European pig manure samples with accuracies of 100%and 98.7%,respectively.Indicators for assessing ARG contamination in Chinese and European pigs also achieved high accuracy(r=0.72-0.88).Escherichia flexneri in both Chinese and European pig populations carried between 21 and 37 ARGs.The results of this study emphasize the importance of global collaboration in reducing antimicrobial resistance risk and provide validated indicators for evaluating the risk of ARG contamination in pig farms.
文摘AIM: To investigate the efficacy of extended antimicrobial prophylaxis (EAP) after gastrectomy by systematic review of literature and meta-analysis. METHODS: Electronic databases of PubMed, Embase, CINAHL, the Cochrane Database of Systematic Reviews, the Cochrane Controlled Trials Register and the China National Knowledge Infrastructure were searched systematically from January 1980 to October 2012. Strict literature retrieval and data extraction were carried out independently by two reviewers and meta-analyses were conducted using RevMan 5.0.2 with statistics tools risk ratios (RRs) and intention-to-treat analyses to evaluate the items of total complications, surgical site infection, incision infection, organ (or space) infection, remote site infection, anastomotic leakage (or dehiscence) and mortality. Fixed model or random model was selected accordingly and forest plot was conducted to display RR. Likewise, Cochrane Risk of Bias Tool was applied to evaluate the quality of randomized controlled trials (RCTs) included in this meta-analysis. RESULTS: A total of 1095 patients with gastric cancer were enrolled in four RCTs. No statistically significant differences were detected between EAP and intraoperative antimicrobial prophylaxis (IAP) in total complications (RR of 0.86, 95%CI: 0.63-1.16, P = 0.32), surgical site infection (RR of 1.97, 95%CI: 0.86-4.48, P = 0.11), incision infection (RR of 4.92, 95%CI: 0.58-41.66, P = 0.14), organ or space infection (RR of 1.55, 95%CI: 0.61-3.89, P = 0.36), anastomotic leakage or dehiscence (RR of 3.85, 95%CI: 0.64-23.17, P = 0.14) and mortality (RR of 1.14, 95%CI: 0.10-13.12; P = 0.92). Likewise, multiple-dose antimicrobial prophylaxis showed no difference compared with single-dose antimicrobial prophylaxis in surgical site infection (RR of 1.10, 95%CI: 0.62-1.93, P = 0.75). Nevertheless, EAP showed a decreased remote site infection rate compared with IAP alone (RR of 0.54, 95%CI: 0.34-0.86, P = 0.01), which is the only significant finding. Unfortunately, EAP did not decrease the incidence of surgical site infections after gastrectomy; likewise, multipledose antimicrobial prophylaxis failed to decrease the incidence of surgical site infection compared with single-dose antimicrobial prophylaxis. CONCLUSION: We recommend that EAP should not be used routinely after gastrectomy until more high-quality RCTs are available.
基金Supported by Natural Science Foundation of Hebei Province(C200700450)~~
文摘[Objective] The study was to explore whether antimicrobial activity of the antimicrobial peptides extracted from immunized Tenebrio molitor varied with different pathogens as inducers.[Method]By inducing T.molitor hungry larvaes to generate immune response via feeding with bacteria and with fungi or actinomycete post to pricking,the antimicrobial peptides extracts were obtained by grinding and centrifuging the cultures.Its antimicrobial activity against 26 pathogens was measured by bacteriostatic ring,and evaluated by trisection to four types and inhibitory spectrum.[Result]Both the antimicrobial activity and antimicrobial spectrum of the antimicrobial peptides extracts varied remarkably among different pathogens as inducers.[Conclusion]Bio-control used strains have obvious advantage in inducing the insect to express body fluid immunity material-antimicrobial peptides.
基金supported by the National Natural Science Foundation of China grant numbers NSFC 81861138053 and NSFC 31761133004。
文摘Objective This study aimed to evaluate the genetic diversity,virulence,and antimicrobial resistance of Aeromonas isolates from clinical patients,tap water systems,and food.Methods Ninety Aeromonas isolates were obtained from Ma’anshan,Anhui province,China,and subjected to multi-locus sequence typing(MLST)with six housekeeping genes.Their taxonomy was investigated using concatenated gyr B-cpn60 sequences,while their resistance to 12 antibiotics was evaluated.Ten putative virulence factors and several resistance genes were identified by PCR and sequencing.Results The 90 Aeromonas isolates were divided into 84 sequence types,80 of which were novel,indicating high genetic diversity.The Aeromonas isolates were classified into eight different species.PCR assays identified virulence genes in the isolates,with the enterotoxin and hemolysin genes act,aer A,alt,and ast found in 47(52.2%),13(14.4%),22(24.4%),and 12(13.3%)of the isolates,respectively.The majority of the isolates(≥90%)were susceptible to aztreonam,imipenem,cefepime,chloramphenicol,gentamicin,tetracycline,and ciprofloxacin.However,several resistance genes were detected in the isolates,as well as a new mcr-3 variant.Conclusions Sequence type,virulence properties,and antibiotic resistance vary in Aeromonas isolates from clinical patients,tap water systems,and food.
文摘Nanomaterials have been found increasing applications in the food sector.Nanostructured antimicrobials can be incorporated either to food matrix of food packaging or to provide extended safety and quality.However,the interactions and effects of nanomaterials with biological systems are still poorly understood.Nanoparticles can enter the organism by oral,dermal and inhalation routes and distributed to different tissues by the circulatory system.Increasing evidence indicate that targeting to specific tissues,cellular uptake and intracellular fate of nanoparticles are strongly influenced by size,shape and surface properties.The specific characteristics of nanomaterials are also determinant for their toxicity in higher organisms.The dose,exposure time and administration route are important aspects influencing toxicity of nanoparticles as well.Both in vitro and in vivo evaluation studies on different types of nanostructures have providing information to support a better understanding about the interactions of nanoscale materials with biological systems.
文摘A simple route to synthesize novel fluorinated fused hetero-polycyclic nitrogen systems containing a pyrazolotriazine moiety (5,8,11) have been deduced from cyclization of 2-aminothiocarbonyl-5-arylidene-3-phenyl-1,2,4-triazin-6(1H)one (2) with diethoxy-phosphine, diethyl carbonate and/or diethyl oxalate in boil THF followed by cyclo condensation with aryl sulfonic acid hydrazide in EtOH/piperidine and finally fluorination with trifluoroethyl acetate. Structures of the products have been established from their elemental analysis and spectral measurements. The antimicrobial activity of the targets has also been evaluated.
文摘There has been a rising interest in using natural antimicrobial compounds in food industry due to current trend of giving value to natural and renewable resources. These antimicrobials provide new modalities to ensure microbial safety and extend the shelf-life of foodstuffs. Natural antimicrobials can be directly added into the food, but several efforts have been made to find alternative solutions to the aim of avoiding undesirable inactivation. Some different ways such as, dipping, spraying, and coating treatment of food are currently applied to product before packaging considered as valid options. The present paper aims to review the use of natural compounds to control microbiological and physicochemical shelf life of major food categories such as, meat, fish, dairy-based products, fruit and vegetables, and cereal-based products.
文摘A laboratory information system (LIS) established in a microbiology department has the potential to play an important role in the quality of microbiology data such as culture of blood, urine, stool, pus swab samples etc. Such data could be effectively utilised to measure the burden of antimicrobial resistance among patients presented to various hospitals and clinics with an episode of an infectious illness of bacterial origin. A variety of clinical and epidemiological investigations are conducted using culture data and the presence of an electronic system such as LIS enhances such investigations and improves the reliability of measures of antimicrobial resistance owing to improved data quality as well as completeness of data gathered as opposed to paper based system. Therefore to improve surveillance of antimicrobial resistance in South Africa, there is a need to reinforce the functionality of the LIS in both public and private microbiology laboratories as this will help to improve internal quality control methodologies.
基金supported by Agriculture and Agri-Food Canada to M.S.Diarra through the Genomics Research and Development Initiative (PSS#1858 J-001262) and A-Base (PSS#3441,J-002363) projects on “Mitigating Antimicrobial Resistance”.
文摘Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and control.Antibiotics have been used not only for the treatment and prevention of such diseases,but also for growth promotion.Consequently,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the environment.To break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’demands.However,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome.Various Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,E.coli)and Gram-positive(Enterococcus spp.,Staphylococcus spp.and C.perfringens)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised chickens.In this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.
文摘Endophytic fungi(EF)colonize plant tissues without causing damage;this relationship brings benefits to both,including a greater resistance to environmental stresses,but the influence of genotypes and culture system in endophytic community is still unraveled.Thus,this work aimed to study EF from Sorghum bicolor and correlate to its genotypes submitted to different culture systems;their potential to produce antimicrobial compounds was also evaluated.To optimize the production of metabolites,four isolates were submitted to liquid medium and the crude extracts of different culture times were analyzed.EF of leaves of Qualimax and SF15 genotypes were isolated after superficial disinfection.Fungal identification was made using classical taxonomy.As results,the traditional system presented the lowest number EF isolates,while the minimum system showed the highest.The genera Aspergillus,Fusarium,Penicillium,Cladosporium,Curvularia and Syncephalastrum were found;Aspergillus spp.was pointed out as a predominant endophyte of genotype Qualimax.Among the 25 endophytes submitted antimicrobial activity assay in solid medium,21 presented antibacterial activity against at least one bacterium with the highest inhibition zone of 29.3 mm of diameter against Staphylococcus aureus.All EF submitted to liquid medium kept the capacity to produce antibacterial metabolites.In conclusion,regardless of genotype and culture system,sorghum is colonized by different EF,mainly Aspergillus spp.EF from leaves of S.bicolor produce antibacterial compounds and their biotechnological applications can be explored in future.
文摘<b><span style="font-family:Verdana;">Introduction:</span></b><span style="font-family:""><span style="font-family:Verdana;"> In the last two decades, the treatment of enteric infections has been complicated by the emergence of antimicrobial resistant strains. Occurrence of multidrug resistant Extended Spectrum Beta Lactamase (ESBL) producing </span><i><span style="font-family:Verdana;">Enterobactaeraceae</span></i><span style="font-family:Verdana;"> pose</span></span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> the greatest risk to public health by raising morbidity and mortality by six folds in developing countries. The present study aims to determine the antibiotics resistance patterns of selected</span><i><span style="font-family:Verdana;"> Entero</span><span style="font-family:Verdana;">bacteriaceae</span></i><span style="font-family:Verdana;"> isolated from commercial poultry production systems i</span><span style="font-family:Verdana;">n Kiamb</span><span><span style="font-family:Verdana;">u County. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> A laboratory based cross-sectional study was co</span></span><span style="font-family:Verdana;">nducted in six purposively selected Sub-Counties of Kiambu County from October 2020, to February 2021. A total of 437 fecal samples were collected from each household. The antibiotic susceptibility testing using disk diffusion method w</span></span><span style="font-family:Verdana;">as</span><span style="font-family:""><span style="font-family:Verdana;"> used against </span><i><span style="font-family:Verdana;">E.</span></i></span><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">coli</span></i><span style="font-family:""><span style="font-family:Verdana;">;</span><i><span style="font-family:Verdana;"> Salmonella spps.</span></i><span style="font-family:Verdana;">;</span><i><span style="font-family:Verdana;"> Shigella spps.</span></i><span style="font-family:Verdana;">;</span><i> </i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Klebsiella spps. </span></i><span style="font-family:Verdana;">which were isolated and identified th</span></span><span style="font-family:Verdana;">r</span><span style="font-family:""><span style="font-family:Verdana;">ough standard biochemical. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Out of 437 fecal and stool samples collected, 591 isolates were recovered with </span><i><span style="font-family:Verdana;">E.</span></i></span><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">coli</span></i><span style="font-family:""><span style="font-family:Verdana;"> (48.9%) being the most frequently identified, followed by </span><i><span style="font-family:Verdana;">Shigella spps.</span></i><span style="font-family:Verdana;"> (18.8%), </span><i><span style="font-family:Verdana;">Salmonella spps.</span></i><span style="font-family:Verdana;"> (18.3%), and </span><i><span style="font-family:Verdana;">Klebsiella spps.</span></i><span style="font-family:Verdana;"> (14.0%). The study shows there was high prevalence of multiple resistance among isolates especially to Sulfamethoxazole (79%), Trimethoprim (71%), and Tetracyclines (59%), correspondingly. Additionally, the isolates showed </span></span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">highest rate of suscep</span><span style="font-family:Verdana;">tibility against Cefuroxime (94%), Gentamicin (93%), Ceftriaxo</span><span style="font-family:Verdana;">ne (91%), Cefepime (89%), Cefotaxime (85%), Ceftazidime (84%), and Chloramphenicol (77%), respectively. </span><b><span style="font-family:Verdana;">Discussion:</span></b><span style="font-family:Verdana;"> Our study indicates that both fecal and stool materials from commercial poultry and humans can be reservoir of multi-drug resistance enteric’s which can be a potential route</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">of transmission of resistance genes, which pose a great risk to public health of Kiambu Residence.
文摘Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases.
文摘The world will benefit from more effective antimicrobial agents against oral conditions arising from the actions of biofilm forming bacteria. Also, information is lacking on the oral biofilm-forming bacterial diversity in Southwestern Nigeria. In this study, we isolate and characterize oral biofilm producing bacteria in the oral cavities of schoolchildren in Southwestern Nigeria. We also investigate the antimicrobial properties of Macrosphyra longistyla extracts against the biofilm-formers and the toxicity of potent extracts. Samples were obtained from 109 schoolchildren aged 4 - 14 years from Lagos, Oyo and Osun States. Agar well diffusion technique was used in the antimicrobial susceptibility testing. Toxicity testing was done using brine shrimps (Artemia salina). Biofilm-formers in this study are Klebsiella sp., Streptococcus sp., Staphylococcus sp., and Micrococcus sp. Ethanol leaf extracts had the highest activity against all biofilm-producing bacteria. Ethanol stem bark extract, which elicited activity against Klebsiella only, was found to be less toxic than the ethanol leaf extract. Staphylococcus showed >10 mm susceptibility to the ethanol and aqueous extracts of Macrosphyra longistyla. Streptococcus and Micrococcus were susceptible to the antimicrobial actions of the ethanolic leaf extracts. Although the ethanol extracts of the leaves had lower minimum inhibitory concentrations than the ethanol extracts of the stem bark, toxicity studies showed ethanol extracts of the stem-bark to be more toxic than the ethanol extracts of the leaves. In conclusion, ethanolic extracts of Macrosphyra longistyla show potential as sources of antimicrobials against gram-positive, oral biofilm-forming bacteria.
文摘Objective: To evaluate the spread of Multidrug-Resistant (MDR) bacterial infections in Bukavu hospitals and test antimicrobial susceptibility patterns of some isolates to usual marketed antibiotics. Methods: The prevalence of MDR strains was determined by using general antimicrobial susceptibility data collected from 3 hospital laboratories. The susceptibility of some isolates to usual antibiotics was processed by agar diffusion method with standard E. coli ATCC8739 and standard antibiotics discs as controls. The tested antibiotics were ampicillin, ceftriaxone, gentamicin, chloramphenicol and ciprofloxacin. Results: At the 3 hospitals, 758 tests were realized in urine, pus, stool, FCV, blood, LCR, split and FU specimens;46 strains were unidentified and 712 strains were identified. Of 712 identified strains, 223 (31.4%) were MDR or XDR strains including Escherichia coli, Klebsiella pneumoniae, Enterobacter, Proteus mirabilis, Salmonella enterica, Pseudomonas aeruginosa, Citrobacter freundii, Morganella morganii, Enterococcus faecalis and E. faecium, Neisseria gonorrohoae, Staphylococcus aureus, coagulase-negative, staphylococci, Streptococcus pneumoniae and Streptococcus pyogenes. Of the infected patients, 36 (21.5%) children were under 16 years and 188 (78.5%) adults were predominately women (58.5%). The susceptibility test showed that all strains but S. aureus were resistant to ampicillin and amoxicillin and ciprofloxacin. Gentamicin, ceftriaxone, and chloramphenicol remain partially active (27% - 80%) against P. mirabilis, E. coli and P. aeruginosa. The resistance is more likely related to strain mutation than to pharmaceutical quality of the antibiotics prescribed. Conclusion: Both data from hospital laboratories and in vitro post-testing findings confirmed the ongoing elevated prevalence of MDR strains in Bukavu. The causes of antibiotic misuse and socio-economic determinants of the phenomenon of resistance should be scrutinized in order to take adequate strategies in the prospective of establishing an effective control system against this threat to overall health. The results of this work on MDR profiles have various implications for the management of infectious diseases. It provides indicators for the surveillance of antimicrobial resistance, practical guidelines for antibiotic susceptibility testing in biomedical laboratories, and guidance for antibiotic therapy.
文摘Some bacteria have the ability to co-exist, proliferate and survive in a multicellular community, biofilm. Each participating bacteria can form its colonies and encases itself by a self-produced insoluble extracellular matrix substance (EPS). Microcolonies within biofilm are held together by interactions and bonding of the substances present in the EPS with their separation from the water channels. Similar to insoluble EPS, bacterial microcolonies release soluble exofactors that have direct impacts on the survivability, growth and antibacterial resistivity of other microcolonies made of single- or multi-species bacteria in the same biofilm. How the exofactors of microcolonies of one-type bacteria impact on microcolonies of other-type bacteria is still unclear. We studied about the role of exofactors released from Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, which are common biofilm-forming pathogenic bacteria. Exofactors facilitate to transform the microenvironment where bacteria can acquire alternative lifestyle with a long survival period and resistivity to certain antimicrobial drugs.
文摘Piptoporellus baudonii, previously known as Laetiporus baudonii, is an African species that was considered to be a sister species to Laetiporus sulphureus, another European species known for its medicinal value. While much is known about the edibility and antimicrobial properties of L. sulphureus, African species like P. baudonii remain understudied. This study investigated the antimicrobial and antioxidant properties of P. baudonii extracts (powder maceration) prepared using ethanol, methanol and water with fractions obtained via differential solubility in hexane, ethyl acetate and n-butanol. Before the antimicrobial analysis, the study material was accurately identified using both morphology and molecular techniques. Antimicrobial activity was tested against fungi, gram-positive, and gram-negative bacteria using a broth serial microdilution method, while antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power FRAP methods. Phylogenetic analysis confirmed the specimen as P. baudonii, with genetic material from Benin grouping it with other P. baudonii from Tanzania and other unknown regions, forming a well-supported clade (100/100). The ethanol (1.71), methanol (2.41) extracts, along with ethyl acetate (1.36), n-butanol (1.18), and hexane (12.91) fractions showed significant antioxidant activity with EC50 values below 20 µg∙mL−1. The highest antimicrobial inhibition was seen in the n-butanol (58%) and ethyl acetate (54%) fractions, followed by ethanol (49%) and hexane (48%). Methanol exhibited the lowest inhibition (46.10%). These values were compared to the standard (Vitamin C). The examined extracts demonstrated high bactericidal properties, with an MBC/MIC ratio (R) of 1 to 4, particularly effective ethyl acetate against Escherichia coli (R = 2) and ethanol extract with strong activity against Enterococcus faecalis (R = 4). Further chemical and cytotoxicity studies are warranted to fully explore the pharmaceutical potential of P. baudonii.
基金Key Research and Development Program of Zhejiang Province,Grant/Award Number:2021C03068。
文摘Objective:To fully understand the overall system and implementation of antimicrobial stewardship(AMS)at different levels in China,an evaluation according to the integrated AMS evaluation tool developed by World Health Organization(WHO)was conducted.Methods:A comprehensive search on the AMS relevant government policies,regulations,scientific research results,public and social activities was conducted,and the implementation of AMS strategies in national,subnational and hospital level were evaluated by the standards of the WHO.Results:The results shew that the system construction,technical infrastructure and actions of AMS in China at the national level is relatively satisfied,but the AMS system needs to be further strengthened at the subnational and the medical institutional level,especially the integration of multidisciplinary teams and relevant departments;the implementation of professional intervention strategies,national education and publicity,professional education and training are relatively weak.AMS implementation is mainly promoted at the national level,and AMS in primary medical institutions is almost missing.It is necessary to carry out AMS at the provincial level and medical institutions as soon as possible.The focus is to establish a professional AMS team,prepare AMS guideline,implement AMS strategy,raise public awareness and ensure the long‐term and sustainable development of AMS in the country.Conclusion:The Chinese government has established a system for AMS,and implemented a multisectoral coordinative mechanism.However,at the subnational and district levels,an AMS system and practice should be set up soon to promote the rational use of antibiotics.
基金supported by National Natural Science Foundation of China(72274067)。
文摘BACKGROUND:Prompt pathogen identification can have a substantial impact on the optimization of antimicrobial treatment.The objective of the study was to assess the diagnostic value of next-generation sequencing(NGS)for identifying pathogen and its clinical impact on antimicrobial intervention in immunocompromised patients with suspected infections.METHODS:This was a retrospective study.Between January and August 2020,47 adult immunocompromised patients underwent NGS testing under the following clinical conditions:1)prolonged fever and negative conventional cultures;2)new-onset fever despite empiric antimicrobial treatment;and 3)afebrile with suspected infections on imaging.Clinical data,including conventional microbial test results and antimicrobial treatment before and after NGS,were collected.Data were analyzed according to documented changes in antimicrobial treatment(escalated,no change,or deescalated)after the NGS results.RESULTS:The median time from hospitalization to NGS sampling was 19 d.Clinically relevant pathogens were detected via NGS in 61.7% of patients(29/47),more than half of whom suffered from fungemia(n=17),resulting in an antimicrobial escalation in 53.2% of patients(25/47)and antimicrobial de-escalation in 0.2% of patients(1/47).Antimicrobial changes were mostly due to the identification of fastidious organisms such as Legionella,Pneumocystis jirovecii,and Candida.In the remaining three cases,NGS detected clinically relevant pathogens also detected by conventional cultures a few days later.The antimicrobial treatment was subsequently adjusted according to the susceptibility test results.Overall,NGS changed antimicrobial management in 55.3%(26/47)of patients,and conventional culture detected clinically relevant pathogens in 14.9% of the patients(7/47).CONCLUSION:With its rapid identification and high sensitivity,NGS could be a promising tool for identifying relevant pathogens and enabling rapid appropriate treatment in immunocompromised patients with suspected infections.