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
BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae inf...BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae infections.Nanodefensin with a 14-carbon saturated fatty acid(ND-C14)is a novel nanoantimicrobial peptide designed by modifying myristic acid at the C-terminus of humanα-defensin 5(HD5)via an amide bond.However,it is unclear whether ND-C14 is effective against lung infections caused by S.pneumoniae.METHODS:In vitro,three groups were established,including the control group,and the HD5 and ND-C14 treatment groups.A virtual colony-count assay was used to evaluate the antibacterial activity of HD5 and ND-C14 against S.pneumoniae.The morphological changes of S.pneumoniae treated with HD5 or ND-C14 were observed by scanning electron microscopy.In vivo,mice were divided into sham,vehicle,and ND-C14 treatment groups.Mice in the sham group were treated with 25μL of phosphate-buffered saline(PBS).Mice in the vehicle and ND-C14 treatment groups were treated with intratracheal instillation of 25μL of bacterial suspension with 2×108 CFU/mL(total bacterial count:5×10^(6) CFU),and then the mice were given 25μL PBS or intratracheally injected with 25μL of ND-C14(including 20μg or 50μg),respectively.Survival rates were evaluated in the vehicle and ND-C14 treatment groups.Bacterial burden in the blood and bronchoalveolar lavage fluid were counted.The lung histology of the mice was assessed.A propidium iodide uptake assay was used to clarify the destructive eff ect of ND-C14 against S.pneumoniae.RESULTS:Compared with HD5,ND-C14 had a better bactericidal eff ect against S.pneumoniae because of its stronger ability to destroy the membrane structure of S.pneumoniae in vitro.In vivo,ND-C14 significantly delayed the death time and improved the survival rate of mice infected with S.pneumoniae.ND-C14 reduced bacterial burden and lung tissue injury.Moreover,ND-C14 had a membrane permeation eff ect on S.pneumoniae,and its destructive ability increased with increasing ND-C14 concentration.CONCLUSION:The ND-C14 may improve bactericidal eff ects on S.pneumoniae both in vitro and in vivo.展开更多
Melittin,a classical antimicrobial peptide,is a highly potent antitumor agent.However,its significant toxicity seriously hampers its application in tumor therapy.In this study,we developed novel melittin analogs with ...Melittin,a classical antimicrobial peptide,is a highly potent antitumor agent.However,its significant toxicity seriously hampers its application in tumor therapy.In this study,we developed novel melittin analogs with pH-responsive,cell-penetrating and membranelytic activities by replacing arginine and lysine with histidine.After conjugation with camptothecin(CPT),CPT-AAM-1 and CPT-AAM-2 were capable of killing tumor cells by releasing CPT at low concentrations and disrupting cell membranes at high concentrations under acidic conditions.Notably,we found that the C-terminus of the melittin analogs was more suitable for drug conjugation than the N-terminus.CPT-AAM-1 significantly suppressed melanoma growth in vivo with relatively low toxicity.Collectively,the present study demonstrates that the development of antitumor drugs based on pH-responsive antimicrobial peptide-drug conjugates is a promising strategy.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
AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collecte...AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.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
Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used thro...Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used throughout the world to reduce the incidence of SSI.However,the correct dosage and frequency of administration remains debatable.In this editorial,we emphasized the determination of the effect of administration of weight-adjusted antimicrobial antibiotic prophylaxis regime on the incidence of SSI and postoperative dosage reduction compared to the conventionally used regime during total joint arthroplasty.The results demonstrated similar efficacy between both regimes with respect to the incidence of SSI.In addition,weight-adjustment led to reduced postoperative dosage and has the potential to reduce chances of achieving lower therapeutic concentration,drug resistance,drug toxicity,and costs.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
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
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
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
Microorganisms are omnipresent in all environments and play mainly the role of transformers, thanks to the multiple enzymes they are able to produce. In order to valorize fermented foods in the Republic of the Congo, ...Microorganisms are omnipresent in all environments and play mainly the role of transformers, thanks to the multiple enzymes they are able to produce. In order to valorize fermented foods in the Republic of the Congo, this work aimed to characterize and study some properties of microorganisms isolated from samples of peppers sold in three markets of Brazzaville. A numeration of the total aerobic mesophilic flora (TAMF) was made in a solid medium, allowing the evaluation of each sample’s microbial concentration. The microbial mass varied from 2.8 × 105 CFU/g for the Ouénzé sample to 1.8 × 104 CFU/g for the Total sample and 2 × 104 CFU/g for the Moungali market sample. The evaluation of the enzymatic properties of the Bacillus isolates showed that 68.42% were capable of producing cellulases and 78.94% were capable of producing amylases and proteases. Antimicrobial activities revealed that 63.15% of the isolates were able to secrete inhibitory substances against E. coli and Staphylococcus aureus. Molecular analysis by PCR amplification, sequencing of the 16S rRNA gene and BLAST bioinformatics analysis provides newly identified bacteria strains with new accession numbers in GenBank: Bacillus thuringiensis MBCBR322 (OP474008), Bacillus megaterium MBCBJ1822 (OP476493), Bacillus thuringiensis MBCBR222 (OP476494), Priestia megaterium MBCBJ2022 (OP476495) and Lactobacillus paraplantarum MBCBR1522 (OP476496). Multiple sequences alignment of identified sequences with their homologs of GenBank has shown high similarities. The phylogenetic inference assay has provided the two groups of strains observed in this study, and the two groups are very coherent with the phylogeny of the reference.展开更多
Background:Many herbal essential oils are potential antimicrobials but their pharmaceutical utility is restricted due to a lack of suitable excipients to mollify their dermatotoxicity and irritant property,and outcome...Background:Many herbal essential oils are potential antimicrobials but their pharmaceutical utility is restricted due to a lack of suitable excipients to mollify their dermatotoxicity and irritant property,and outcome of their therapeutic use may vary with different diluents used.Methods:Effect of 16 diluents(dimethyl sulfoxide,liquid paraffin,glycerine,oils of mustard,sunflower,rice bran,palm,groundnut,olive,coconut,sesame,avocado,jojoba,castor,linseed and soybean)was assessed on antimicrobial activity of 2%cinnamon(Cinnamomum zelylanicum album),thyme(Thymus vulgaris)and ajowan(Trachyspermum ammi)oils using agar well diffusion assay.The effect of excipients was evaluated on six Candida albicans,five Escherichia coli,four Acinetobacter lwoffii,two strains each of Staphylococcus aureus,Enterobacter agglomerans,and Enterococcus faecium and one strain each of Acinetobacter calcoaceticus,Escherichia fergusonii,Klebsiella oxytoca,K.pneumoniae ssp.pneumoniae,Leclercia adecarboxylata,Paenibacillus amylolyticus,Proteus mirabilis,P.vulgaris,Pseudomonas aeruginosa,Raoultella terrigena,Staphylococcus capitis ssp.capitis,S.chromogenes,S.epidermidis,S.warneri and Streptococcus pyogenes.Results:Thyme oil(2%)maintained it antimicrobial activity on dilution in dimethyl sulfoxide and glycerine,and ajowan oil(2%)completely lost its antibacterial activity in all diluents except dimethyl sulfoxide.However,cinnamon oil partially lost its antimicrobial activity upon dilution in glycerine,vegetable,and mineral oils in comparison to dimethyl sulfoxide.Olive oil was the best vegetable oil,almost comparable to dimethyl sulfoxide and castor oil was the worst diluent for maintaining antimicrobial activity of cinnamon oil.Conclusion:The study indicated the non-suitability of vegetable oils for pharmaceutical formulations of essential oils except olive oil for dilution of cinnamon oil and glycerol for thyme oil to replace dimethyl sulfoxide as diluent.展开更多
Background:The uroculturome indicates the profile of culturable microbes inhabiting the urinary tract,and it is often required to do a urine culture to find an effective antimicrobial to treat urinary tract infections...Background:The uroculturome indicates the profile of culturable microbes inhabiting the urinary tract,and it is often required to do a urine culture to find an effective antimicrobial to treat urinary tract infections(UTIs).Methods:This study targeted to understand the profile of culturable pathogens in the urine of apparently healthy(128)and humans with clinical UTIs(161)and their antimicrobial susceptibility.All the urine samples were analyzed to quantify microbial load and determine the diversity and antimicrobial susceptibility of microbes following standard microbiological methods.Results:In urine samples from UTI cases,microbial counts were 1.2×10^(4)±6.02×10^(3) colony-forming units(cfu)/mL,while in urine samples from apparently healthy humans,the average count was 3.33±1.34×10^(3) cfu/mL.In eight samples(six from UTI cases and two from apparently healthy people,Candida(C.albicans 3,C.catenulata 1,C.krusei 1,C.tropicalis 1,C.parapsiplosis 1,C.gulliermondii 1)and Rhizopus species(1)were detected.Candida krusei was detected only in a single urine sample from a healthy person and C.albicans was detected both in urine of healthy and clinical UTI cases.Gram-positive(G+ve)bacteria were more commonly(Odds ratio,1.98;CI99,1.01-3.87)detected in urine samples of apparently healthy humans,and Gram-negative(G−ve)bacteria(Odds ratio,2.74;CI99,1.44-5.23)in urines of UTI cases.From urine samples of 161 UTI cases,a total of 90 different types of microbes were detected and,73 samples had only a single type of bacteria.In contrast,49,29,3,4,1,and 2 samples had 2,3,4,5,6 and 7 types of bacteria,respectively.The most common bacteria detected in urine of UTI cases was Escherichia coli(52 samples),in 20 cases as the single type of bacteria,other 34 types of bacteria were detected in pure form in 53 cases.From 128 urine samples of apparently healthy people,88 types of microbes were detected either singly or in association with others,from 64 urine samples only a single type of bacteria was detected while 34,13,3,11,2 and 1 sample yielded 2,3,4,5,6 and seven types of microbes,respectively.In the urine of apparently healthy humans too,E.coli was the most common bacteria,(10 samples)followed by Staphylococcus haemolyticus(9),S.intermedius(5),and S.aureus(5),and similar types of bacteria also dominated in cases of mixed occurrence,E.coli was detected in 26,S.aureus in 22 and S.haemolyticus in 19 urine samples,respectively.G+ve bacteria isolated from urine samples’irrespective of health status were more often(P<0.01)resistant than G−ve bacteria to ajowan oil,holy basil oil,cinnamaldehyde,and cinnamon oil,but more susceptible to sandalwood oil(P<0.01).However,for antibiotics,G+ve were more often susceptible than G−ve bacteria to cephalosporins,doxycycline,and nitrofurantoin.Conclusion:The study concludes that to understand the role of good and bad bacteria in the urinary tract microbiome more targeted studies are needed to discern the isolates at the pathotype level.Further,the study suggests the use of antibiotics by observing good antibiotic stewardship following antibiotic susceptibility testing only.展开更多
Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides...Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications.展开更多
Copper nanoparticles(CuNPs)have emerged as a promising alternative due to their unique antimicrobial properties.The synthesis of CuNPs using Asparagus racemosus,commonly known as Shatavari,offers a sustainable and env...Copper nanoparticles(CuNPs)have emerged as a promising alternative due to their unique antimicrobial properties.The synthesis of CuNPs using Asparagus racemosus,commonly known as Shatavari,offers a sustainable and environmentally friendly approach to producing nanomaterials.Moreover,the resulting CuNPs have been found to possess excellent antibacterial,and antioxidant properties,which further expands their potential applications in medicine and environmental remediation.In this article,we discussed the in vitro characterization of the CuNPs.In vitro studies revealed that CuNPs have the potential for biomedical applications and as a base nanomaterial for the construction of drug delivery and targeting vehicles.展开更多
The recent global spread of the pandemic underscores the necessity of seeking new materials effective against microorganisms. Nanotechnology offers avenues for developing multifunctional materials. In this study, alph...The recent global spread of the pandemic underscores the necessity of seeking new materials effective against microorganisms. Nanotechnology offers avenues for developing multifunctional materials. In this study, alpha-titanium phosphate (α-TiP) nanoparticles were synthesized and treated with silver salt to enhance their antimicrobial properties. The physicochemical characteristics and antimicrobial activity were evaluated. It was revealed by X-ray diffraction analysis that the structural integrity of α-TiP was influenced by ethylenediamine and silver ions. Distinct degradation profiles for each chemical modification were shown by thermogravimetric analysis. Infrared spectroscopy detected shifts and new absorption peaks in the spectra depending on the type of modification. Energy dispersive spectroscopy confirmed the disaggregation of α-TiP galleries following the addition of silver salt, which increased their effectiveness against microorganisms. Notably, only the sample treated with silver ions exhibited antimicrobial action. Antimicrobial activity was tested against the bacteria of medical importance Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Listeria momocytogenes and the yeast Candida albicans. All microorganisms were inhibited by sample containing silver. Minor inhibition was observed against the Gram-positive bacteria L. monocytogenes and Bacillus cereus, while the greatest inhibition occurred against the fungus (yeast) C. albicans. The results revealed a potential application of the nanoparticles for control of microorganisms in public health.展开更多
Objective:To analyze the therapeutic effect of Xuebijing+antimicrobials in intensive care unit(ICU)patients with severe pneumonia.Methods:60 ICU patients with severe pneumonia from June 2021 to June 2023 were selected...Objective:To analyze the therapeutic effect of Xuebijing+antimicrobials in intensive care unit(ICU)patients with severe pneumonia.Methods:60 ICU patients with severe pneumonia from June 2021 to June 2023 were selected and divided by the random number table method,with 30 cases in each group.The observation group received Xuebijing+antimicrobial treatment,while the control group received only antimicrobial treatment.The differences in rehabilitation indexes,test indexes,and inflammation indexes were compared between the two groups.Results:Mechanical ventilation time,fever reduction time,cough relief time,and hospitalization time of the observation group were significantly shorter than those of the control group(P<0.05);C-reactive protein,procalcitonin,and white blood cell count of the observation group were significantly lower than those of the control group(P<0.05);interleukin-6 and tumor necrosis factor-aαof the observation group were significantly lower than those of the control group(P<0.05).Conclusion:The treatment of severe pneumonia patients in ICU with Xuebijing+antibacterial drugs can reduce inflammation,enhance immune function,shorten the pneumonia recovery time,and reduce the adverse reactions of severe pneumonia.展开更多
Introduction: The inappropriate antimicrobial usage (AMU) in chicken production has led to an increase in the prevalence of antimicrobial resistance (AMR). In Zambia, there is little information documented regarding t...Introduction: The inappropriate antimicrobial usage (AMU) in chicken production has led to an increase in the prevalence of antimicrobial resistance (AMR). In Zambia, there is little information documented regarding the knowledge, attitude, and practices of poultry farmers on AMU and AMR. Therefore, this study assessed the knowledge, attitude and practices regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Methods: This was a cross-sectional study conducted among 106 poultry farmers from November to December 2021 using a structured questionnaire. Data analysis was done using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: Overall, of the 106 participants, 90.6% knew what antimicrobials were, but only 29.2% were aware of AMR. The study showed that 46.2% of the participants had low knowledge, 71.7% had negative attitudes, and 61.3% had poor practices regarding AMR. The prevalence of antibiotic use in poultry production was 83%. The most used antimicrobials were tetracycline (84%) and gentamicin (35.2%). The commonly reported reason for the use of antimicrobials was for the treatment (93.2%) and prevention (89.8%) of diseases. Further, 76.9% of the administered antimicrobials were usually done without veterinarian consultation or prescription. Conclusion: The study shows that there was high AMU in poultry farms in Kitwe. However, there was low knowledge, negative attitude, and poor practices towards AMU and AMR. Therefore, there is a need for educational and sensitisation programmes regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Alongside this, antimicrobial stewardship and surveillance systems should be strengthened in the livestock production sector. This will ensure food safety and public health.展开更多
Background: Antimicrobial resistance (AMR) is a global health challenge that has escalated due to the inappropriate use of antimicrobials in humans, animals, and the environment. Developing and implementing strategies...Background: Antimicrobial resistance (AMR) is a global health challenge that has escalated due to the inappropriate use of antimicrobials in humans, animals, and the environment. Developing and implementing strategies to reduce and combat AMR is critical. Purpose: This study aimed to highlight some global strategies that can be implemented to address AMR using a One Health approach. Methods: This study employed a narrative review design that included studies published from January 2002 to July 2023. The study searched for literature on AMR and antimicrobial stewardship (AMS) in PubMed and Google Scholar using the 2020 PRISMA guidelines. Results: This study reveals that AMR remains a significant global public health problem. Its severity has been markedly exacerbated by inappropriate use of antimicrobials in humans, animals, and the broader ecological environment. Several strategies have been developed to address AMR, including the Global Action Plan (GAP), National Action Plans (NAPs), AMS programs, and implementation of the AWaRe classification of antimicrobials. These strategies also involve strengthening surveillance of antimicrobial consumption and resistance, encouraging the development of new antimicrobials, and enhancing regulations around antimicrobial prescribing, dispensing, and usage. Additional measures include promoting global partnerships, combating substandard and falsified antimicrobials, advocating for vaccinations, sanitation, hygiene and biosecurity, as well as exploring alternatives to antimicrobials. However, the implementation of these strategies faces various challenges. These challenges include low awareness and knowledge of AMR, a shortage of human resources and capacity building for AMR and AMS, in adequate funding for AMR and AMS initiatives, limited laboratory capacities for surveillance, behavioural change issues, and ineffective leadership and multidisciplinary teams. Conclusion: In conclusion, this study established that AMR is prevalent among humans, animals, and the environment. Successfully addressing AMR calls for a collaborative, multifaceted One Health approach. Despite this, some gaps remain effectively implementing strategies currently recommended to combat AMR. As a result, it is essential to reinforce the strategies that are deployed to counter AMR across the human, animal, and environmental sectors.展开更多
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.
基金supported by the National Natural Science Foundation of China(82072148)Zhejiang Provincial Basic Public Welfare Research Program of Zhejiang Province(LGF21H150002)+1 种基金Zhejiang Medicine and Health Science and Technology Project(2022RC245&2023KY255)Ningbo Municipal Natural Science Foundation(2023J134).
文摘BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae infections.Nanodefensin with a 14-carbon saturated fatty acid(ND-C14)is a novel nanoantimicrobial peptide designed by modifying myristic acid at the C-terminus of humanα-defensin 5(HD5)via an amide bond.However,it is unclear whether ND-C14 is effective against lung infections caused by S.pneumoniae.METHODS:In vitro,three groups were established,including the control group,and the HD5 and ND-C14 treatment groups.A virtual colony-count assay was used to evaluate the antibacterial activity of HD5 and ND-C14 against S.pneumoniae.The morphological changes of S.pneumoniae treated with HD5 or ND-C14 were observed by scanning electron microscopy.In vivo,mice were divided into sham,vehicle,and ND-C14 treatment groups.Mice in the sham group were treated with 25μL of phosphate-buffered saline(PBS).Mice in the vehicle and ND-C14 treatment groups were treated with intratracheal instillation of 25μL of bacterial suspension with 2×108 CFU/mL(total bacterial count:5×10^(6) CFU),and then the mice were given 25μL PBS or intratracheally injected with 25μL of ND-C14(including 20μg or 50μg),respectively.Survival rates were evaluated in the vehicle and ND-C14 treatment groups.Bacterial burden in the blood and bronchoalveolar lavage fluid were counted.The lung histology of the mice was assessed.A propidium iodide uptake assay was used to clarify the destructive eff ect of ND-C14 against S.pneumoniae.RESULTS:Compared with HD5,ND-C14 had a better bactericidal eff ect against S.pneumoniae because of its stronger ability to destroy the membrane structure of S.pneumoniae in vitro.In vivo,ND-C14 significantly delayed the death time and improved the survival rate of mice infected with S.pneumoniae.ND-C14 reduced bacterial burden and lung tissue injury.Moreover,ND-C14 had a membrane permeation eff ect on S.pneumoniae,and its destructive ability increased with increasing ND-C14 concentration.CONCLUSION:The ND-C14 may improve bactericidal eff ects on S.pneumoniae both in vitro and in vivo.
基金supported by the grants from the National Natural Science Foundation of China(Nos.81773566 and 21602092)Innovation Project of Medicine and Health Science and Technology of Chinese Academy of Medical Sciences(2019-I2M-5-074)+1 种基金the Funds for Fundamental Research Creative Groups of Gansu Province(No.20JR5RA310)the Fundamental Research Funds for the Central Universities(No.lzujbky-2021-38).
文摘Melittin,a classical antimicrobial peptide,is a highly potent antitumor agent.However,its significant toxicity seriously hampers its application in tumor therapy.In this study,we developed novel melittin analogs with pH-responsive,cell-penetrating and membranelytic activities by replacing arginine and lysine with histidine.After conjugation with camptothecin(CPT),CPT-AAM-1 and CPT-AAM-2 were capable of killing tumor cells by releasing CPT at low concentrations and disrupting cell membranes at high concentrations under acidic conditions.Notably,we found that the C-terminus of the melittin analogs was more suitable for drug conjugation than the N-terminus.CPT-AAM-1 significantly suppressed melanoma growth in vivo with relatively low toxicity.Collectively,the present study demonstrates that the development of antitumor drugs based on pH-responsive antimicrobial peptide-drug conjugates is a promising strategy.
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.
文摘AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.
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Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used throughout the world to reduce the incidence of SSI.However,the correct dosage and frequency of administration remains debatable.In this editorial,we emphasized the determination of the effect of administration of weight-adjusted antimicrobial antibiotic prophylaxis regime on the incidence of SSI and postoperative dosage reduction compared to the conventionally used regime during total joint arthroplasty.The results demonstrated similar efficacy between both regimes with respect to the incidence of SSI.In addition,weight-adjustment led to reduced postoperative dosage and has the potential to reduce chances of achieving lower therapeutic concentration,drug resistance,drug toxicity,and costs.
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.
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Microorganisms are omnipresent in all environments and play mainly the role of transformers, thanks to the multiple enzymes they are able to produce. In order to valorize fermented foods in the Republic of the Congo, this work aimed to characterize and study some properties of microorganisms isolated from samples of peppers sold in three markets of Brazzaville. A numeration of the total aerobic mesophilic flora (TAMF) was made in a solid medium, allowing the evaluation of each sample’s microbial concentration. The microbial mass varied from 2.8 × 105 CFU/g for the Ouénzé sample to 1.8 × 104 CFU/g for the Total sample and 2 × 104 CFU/g for the Moungali market sample. The evaluation of the enzymatic properties of the Bacillus isolates showed that 68.42% were capable of producing cellulases and 78.94% were capable of producing amylases and proteases. Antimicrobial activities revealed that 63.15% of the isolates were able to secrete inhibitory substances against E. coli and Staphylococcus aureus. Molecular analysis by PCR amplification, sequencing of the 16S rRNA gene and BLAST bioinformatics analysis provides newly identified bacteria strains with new accession numbers in GenBank: Bacillus thuringiensis MBCBR322 (OP474008), Bacillus megaterium MBCBJ1822 (OP476493), Bacillus thuringiensis MBCBR222 (OP476494), Priestia megaterium MBCBJ2022 (OP476495) and Lactobacillus paraplantarum MBCBR1522 (OP476496). Multiple sequences alignment of identified sequences with their homologs of GenBank has shown high similarities. The phylogenetic inference assay has provided the two groups of strains observed in this study, and the two groups are very coherent with the phylogeny of the reference.
基金supported by grants received from CAAST-ACLH(NAHEP/CAAST/2018-19)of ICAR-World Bank-funded National Agricultural Higher Education Project(NAHEP).
文摘Background:Many herbal essential oils are potential antimicrobials but their pharmaceutical utility is restricted due to a lack of suitable excipients to mollify their dermatotoxicity and irritant property,and outcome of their therapeutic use may vary with different diluents used.Methods:Effect of 16 diluents(dimethyl sulfoxide,liquid paraffin,glycerine,oils of mustard,sunflower,rice bran,palm,groundnut,olive,coconut,sesame,avocado,jojoba,castor,linseed and soybean)was assessed on antimicrobial activity of 2%cinnamon(Cinnamomum zelylanicum album),thyme(Thymus vulgaris)and ajowan(Trachyspermum ammi)oils using agar well diffusion assay.The effect of excipients was evaluated on six Candida albicans,five Escherichia coli,four Acinetobacter lwoffii,two strains each of Staphylococcus aureus,Enterobacter agglomerans,and Enterococcus faecium and one strain each of Acinetobacter calcoaceticus,Escherichia fergusonii,Klebsiella oxytoca,K.pneumoniae ssp.pneumoniae,Leclercia adecarboxylata,Paenibacillus amylolyticus,Proteus mirabilis,P.vulgaris,Pseudomonas aeruginosa,Raoultella terrigena,Staphylococcus capitis ssp.capitis,S.chromogenes,S.epidermidis,S.warneri and Streptococcus pyogenes.Results:Thyme oil(2%)maintained it antimicrobial activity on dilution in dimethyl sulfoxide and glycerine,and ajowan oil(2%)completely lost its antibacterial activity in all diluents except dimethyl sulfoxide.However,cinnamon oil partially lost its antimicrobial activity upon dilution in glycerine,vegetable,and mineral oils in comparison to dimethyl sulfoxide.Olive oil was the best vegetable oil,almost comparable to dimethyl sulfoxide and castor oil was the worst diluent for maintaining antimicrobial activity of cinnamon oil.Conclusion:The study indicated the non-suitability of vegetable oils for pharmaceutical formulations of essential oils except olive oil for dilution of cinnamon oil and glycerol for thyme oil to replace dimethyl sulfoxide as diluent.
基金supported by grants received from CAAST-ACLH(NAHEP/CAAST/2018-19)of ICAR-World Bank-funded National Agricultural Higher Education Project(NAHEP).
文摘Background:The uroculturome indicates the profile of culturable microbes inhabiting the urinary tract,and it is often required to do a urine culture to find an effective antimicrobial to treat urinary tract infections(UTIs).Methods:This study targeted to understand the profile of culturable pathogens in the urine of apparently healthy(128)and humans with clinical UTIs(161)and their antimicrobial susceptibility.All the urine samples were analyzed to quantify microbial load and determine the diversity and antimicrobial susceptibility of microbes following standard microbiological methods.Results:In urine samples from UTI cases,microbial counts were 1.2×10^(4)±6.02×10^(3) colony-forming units(cfu)/mL,while in urine samples from apparently healthy humans,the average count was 3.33±1.34×10^(3) cfu/mL.In eight samples(six from UTI cases and two from apparently healthy people,Candida(C.albicans 3,C.catenulata 1,C.krusei 1,C.tropicalis 1,C.parapsiplosis 1,C.gulliermondii 1)and Rhizopus species(1)were detected.Candida krusei was detected only in a single urine sample from a healthy person and C.albicans was detected both in urine of healthy and clinical UTI cases.Gram-positive(G+ve)bacteria were more commonly(Odds ratio,1.98;CI99,1.01-3.87)detected in urine samples of apparently healthy humans,and Gram-negative(G−ve)bacteria(Odds ratio,2.74;CI99,1.44-5.23)in urines of UTI cases.From urine samples of 161 UTI cases,a total of 90 different types of microbes were detected and,73 samples had only a single type of bacteria.In contrast,49,29,3,4,1,and 2 samples had 2,3,4,5,6 and 7 types of bacteria,respectively.The most common bacteria detected in urine of UTI cases was Escherichia coli(52 samples),in 20 cases as the single type of bacteria,other 34 types of bacteria were detected in pure form in 53 cases.From 128 urine samples of apparently healthy people,88 types of microbes were detected either singly or in association with others,from 64 urine samples only a single type of bacteria was detected while 34,13,3,11,2 and 1 sample yielded 2,3,4,5,6 and seven types of microbes,respectively.In the urine of apparently healthy humans too,E.coli was the most common bacteria,(10 samples)followed by Staphylococcus haemolyticus(9),S.intermedius(5),and S.aureus(5),and similar types of bacteria also dominated in cases of mixed occurrence,E.coli was detected in 26,S.aureus in 22 and S.haemolyticus in 19 urine samples,respectively.G+ve bacteria isolated from urine samples’irrespective of health status were more often(P<0.01)resistant than G−ve bacteria to ajowan oil,holy basil oil,cinnamaldehyde,and cinnamon oil,but more susceptible to sandalwood oil(P<0.01).However,for antibiotics,G+ve were more often susceptible than G−ve bacteria to cephalosporins,doxycycline,and nitrofurantoin.Conclusion:The study concludes that to understand the role of good and bad bacteria in the urinary tract microbiome more targeted studies are needed to discern the isolates at the pathotype level.Further,the study suggests the use of antibiotics by observing good antibiotic stewardship following antibiotic susceptibility testing only.
文摘Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications.
文摘Copper nanoparticles(CuNPs)have emerged as a promising alternative due to their unique antimicrobial properties.The synthesis of CuNPs using Asparagus racemosus,commonly known as Shatavari,offers a sustainable and environmentally friendly approach to producing nanomaterials.Moreover,the resulting CuNPs have been found to possess excellent antibacterial,and antioxidant properties,which further expands their potential applications in medicine and environmental remediation.In this article,we discussed the in vitro characterization of the CuNPs.In vitro studies revealed that CuNPs have the potential for biomedical applications and as a base nanomaterial for the construction of drug delivery and targeting vehicles.
文摘The recent global spread of the pandemic underscores the necessity of seeking new materials effective against microorganisms. Nanotechnology offers avenues for developing multifunctional materials. In this study, alpha-titanium phosphate (α-TiP) nanoparticles were synthesized and treated with silver salt to enhance their antimicrobial properties. The physicochemical characteristics and antimicrobial activity were evaluated. It was revealed by X-ray diffraction analysis that the structural integrity of α-TiP was influenced by ethylenediamine and silver ions. Distinct degradation profiles for each chemical modification were shown by thermogravimetric analysis. Infrared spectroscopy detected shifts and new absorption peaks in the spectra depending on the type of modification. Energy dispersive spectroscopy confirmed the disaggregation of α-TiP galleries following the addition of silver salt, which increased their effectiveness against microorganisms. Notably, only the sample treated with silver ions exhibited antimicrobial action. Antimicrobial activity was tested against the bacteria of medical importance Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Listeria momocytogenes and the yeast Candida albicans. All microorganisms were inhibited by sample containing silver. Minor inhibition was observed against the Gram-positive bacteria L. monocytogenes and Bacillus cereus, while the greatest inhibition occurred against the fungus (yeast) C. albicans. The results revealed a potential application of the nanoparticles for control of microorganisms in public health.
文摘Objective:To analyze the therapeutic effect of Xuebijing+antimicrobials in intensive care unit(ICU)patients with severe pneumonia.Methods:60 ICU patients with severe pneumonia from June 2021 to June 2023 were selected and divided by the random number table method,with 30 cases in each group.The observation group received Xuebijing+antimicrobial treatment,while the control group received only antimicrobial treatment.The differences in rehabilitation indexes,test indexes,and inflammation indexes were compared between the two groups.Results:Mechanical ventilation time,fever reduction time,cough relief time,and hospitalization time of the observation group were significantly shorter than those of the control group(P<0.05);C-reactive protein,procalcitonin,and white blood cell count of the observation group were significantly lower than those of the control group(P<0.05);interleukin-6 and tumor necrosis factor-aαof the observation group were significantly lower than those of the control group(P<0.05).Conclusion:The treatment of severe pneumonia patients in ICU with Xuebijing+antibacterial drugs can reduce inflammation,enhance immune function,shorten the pneumonia recovery time,and reduce the adverse reactions of severe pneumonia.
文摘Introduction: The inappropriate antimicrobial usage (AMU) in chicken production has led to an increase in the prevalence of antimicrobial resistance (AMR). In Zambia, there is little information documented regarding the knowledge, attitude, and practices of poultry farmers on AMU and AMR. Therefore, this study assessed the knowledge, attitude and practices regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Methods: This was a cross-sectional study conducted among 106 poultry farmers from November to December 2021 using a structured questionnaire. Data analysis was done using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: Overall, of the 106 participants, 90.6% knew what antimicrobials were, but only 29.2% were aware of AMR. The study showed that 46.2% of the participants had low knowledge, 71.7% had negative attitudes, and 61.3% had poor practices regarding AMR. The prevalence of antibiotic use in poultry production was 83%. The most used antimicrobials were tetracycline (84%) and gentamicin (35.2%). The commonly reported reason for the use of antimicrobials was for the treatment (93.2%) and prevention (89.8%) of diseases. Further, 76.9% of the administered antimicrobials were usually done without veterinarian consultation or prescription. Conclusion: The study shows that there was high AMU in poultry farms in Kitwe. However, there was low knowledge, negative attitude, and poor practices towards AMU and AMR. Therefore, there is a need for educational and sensitisation programmes regarding AMU and AMR among poultry farmers in Kitwe, Zambia. Alongside this, antimicrobial stewardship and surveillance systems should be strengthened in the livestock production sector. This will ensure food safety and public health.
文摘Background: Antimicrobial resistance (AMR) is a global health challenge that has escalated due to the inappropriate use of antimicrobials in humans, animals, and the environment. Developing and implementing strategies to reduce and combat AMR is critical. Purpose: This study aimed to highlight some global strategies that can be implemented to address AMR using a One Health approach. Methods: This study employed a narrative review design that included studies published from January 2002 to July 2023. The study searched for literature on AMR and antimicrobial stewardship (AMS) in PubMed and Google Scholar using the 2020 PRISMA guidelines. Results: This study reveals that AMR remains a significant global public health problem. Its severity has been markedly exacerbated by inappropriate use of antimicrobials in humans, animals, and the broader ecological environment. Several strategies have been developed to address AMR, including the Global Action Plan (GAP), National Action Plans (NAPs), AMS programs, and implementation of the AWaRe classification of antimicrobials. These strategies also involve strengthening surveillance of antimicrobial consumption and resistance, encouraging the development of new antimicrobials, and enhancing regulations around antimicrobial prescribing, dispensing, and usage. Additional measures include promoting global partnerships, combating substandard and falsified antimicrobials, advocating for vaccinations, sanitation, hygiene and biosecurity, as well as exploring alternatives to antimicrobials. However, the implementation of these strategies faces various challenges. These challenges include low awareness and knowledge of AMR, a shortage of human resources and capacity building for AMR and AMS, in adequate funding for AMR and AMS initiatives, limited laboratory capacities for surveillance, behavioural change issues, and ineffective leadership and multidisciplinary teams. Conclusion: In conclusion, this study established that AMR is prevalent among humans, animals, and the environment. Successfully addressing AMR calls for a collaborative, multifaceted One Health approach. Despite this, some gaps remain effectively implementing strategies currently recommended to combat AMR. As a result, it is essential to reinforce the strategies that are deployed to counter AMR across the human, animal, and environmental sectors.
