UV-Based Advanced Oxidation Processes for Antibiotic Resistance Control: Efficiency, Influencing Factors, and Energy Consumption

Antibiotic resistant bacteria(ARB)with antibiotic resistance genes(ARGs)can reduce or eliminate the effectiveness of antibiotics and thus threaten human health.The United Nations Environment Programme considers antibiotic resistance the first of six emerging issues of concern.Advanced oxidation processes(AOPs)that combine ultraviolet(UV)irradiation and chemical oxidation(primarily chlorine,hydrogen peroxide,and persulfate)have attracted increasing interest as advanced water and wastewater treatment technologies.These integrated technologies have been reported to significantly elevate the efficiencies of ARB inactivation and ARG degradation compared with direct UV irradiation or chemical oxidation alone due to the generation of multiple reactive species.In this study,the performance and underlying mechanisms of UV/chlorine,UV/hydrogen peroxide,and UV/persulfate processes for controlling ARB and ARGs were reviewed based on recent studies.Factors affecting the process-specific efficiency in controlling ARB and ARGs were discussed,including biotic factors,oxidant dose,UV fluence,pH,and water matrix properties.In addition,the cost-effectiveness of the UV-based AOPs was evaluated using the concept of electrical energy per order.The UV/chlorine process exhibited a higher efficiency with lower energy consumption than other UV-based AOPs in the wastewater matrix,indicating its potential for ARB inactivation and ARG degradation in wastewater treatment.Further studies are required to address the trade-off between toxic byproduct formation and the energy efficiency of the UV/chlorine process in real wastewater to facilitate its optimization and application in the control of ARB and ARGs.

Five-year analysis of isolated pathogens and antibiotic resistance of ocular infections from two large tertiary comprehensive hospitals in east China

AIM:To analyze the spectrum of isolated pathogens and antibiotic resistance for ocular infections within 5y at two tertiary hospitals in east China.METHODS:Ocular specimen data were collected from January 2019 to October 2023.The pathogen spectrum and positive culture rate for different infection location,such as keratitis,endophthalmitis,and periocular infections,along with antibiotic resistance were analyzed.RESULTS:We included 2727 specimens,including 827(30.33%)positive cultures.A total of 871 strains were isolated,530(60.85%)bacterial and 341(39.15%)fungal strains were isolated.Gram-positive cocci(GPC)were the most common ocular pathogens.The most common bacterial isolates were Staphylococcus epidermidis(25.03%),Staphylococcus aureus(7.46%),Streptococcus pneumoniae(4.59%),Corynebacterium macginleyi(3.44%),and Pseudomonas aeruginosa(3.33%).The most common fungal genera were Fusarium spp.(12.74%),Aspergillus spp.(6.54%),and Scedosporium spp.(5.74%).Staphylococcus epidermidis strains showed more than 50%resistance to fluoroquinolones.Streptococcus pneumoniae and Corynebacterium macginleyi showed more than 90%resistance to erythromycin.The percentage of bacteria showing multidrug resistance(MDR)significantly decreased(χ^(2)=17.44,P=0.002).CONCLUSION:GPC are the most common ocular pathogens.Corynebacterium macginleyi,as the fourth common bacterium,may currently be the local microbiological feature of east China.Fusarium spp.is the most common fungus.More than 50%of the GPC are resistant to fluoroquinolones,penicillins,and macrolides.However,the proportion of MDR strains has been reduced over time.

Mobile genetic elements facilitate the transmission of antibiotic resistance genes in multidrug-resistant Enterobacteriaceae from duck farms

Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public health.The phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms in Zhejiang Province,China,were investigated.A total of 215 isolates were identified as Escherichia coli(64.65%),Klebsiella pneumoniae(12.09%),Proteus mirabilis(10.23%),Salmonella(8.84%),and Enterobacter cloacae(4.19%).Meanwhile,all isolates were resistant to at least two antibiotics.Most isolates carried tet(A)(85.12%),blaTEM(78.60%)and sul1(67.44%)resistance genes.Gene co-occurrence analysis showed that the resistance genes were associated with IS26 and integrons.A conjugative IncFII plasmid pSDM004 containing all the above MGEs was detected in Proteus mirabilis isolate SDM004.This isolate was resistant to 18 antibiotics and carried the blaNDM-5 gene.MGEs,especially plasmids,are the primary antibiotic resistance gene transmission route in duck farms.These findings provide a theoretical basis for the rational use of antibiotics in farms which are substantial for evaluating public health and food safety.

Nonlinear impacts of temperature on antibiotic resistance in Escherichia coli

The increase in bacterial antibiotic resistance poses a significant threat to the effectiveness of antibiotics,and there is growing evidence suggesting that global warming may speed up this process.However,the direct influence of temperature on the development of antibiotic resistance and the underlying mechanisms is not yet fully understood.Here we show that antibiotic resistance exhibits a nonlinear response to elevated temperatures under the combined stress of temperatures and antibiotics.We find that the effectiveness of gatifloxacin against Escherichia coli significantly diminishes at 42°C,while resistance increases 256-fold at 27°C.Additionally,the increased transcription levels of genes such as marA,ygfA,and ibpB with rising temperatures,along with gene mutations at different sites,explain the observed variability in resistance patterns.These findings highlight the complexity of antibiotic resistance evolution and the urgent need for comprehensive studies to understand and mitigate the effects of global warming on antibiotic resistance.

Nature’s Pharmacy under Siege: Investigating Antibiotic Resistance Pattern in Endophytic Bacteria of Medicinal Plants

Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors.

Exploring the impact of rotavirus vaccination on antibiotic prescription and resistance:A comprehensive systematic review

BACKGROUND Rotavirus is a highly contagious virus responsible for a significant burden of acute gastroenteritis,particularly among infants and young children worldwide,however,vaccination against this viral agent is available.Several studies have hypothesized that rotavirus vaccination has been linked to lower rates of antibiotic resistance.AIM To assess the relationship between rotavirus vaccination and antibiotic resistance.METHODS The present systematic review was tailored based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.Several electronic databases(PubMed/MEDLINE,Scopus and Web of Science)were searched independently by two investigators in order to retrieve relevant publications published until April 2023 that investigated the aforementioned research question.RESULTS The comprehensive database search identified a total of 91 records.After the duplicates were removed(n=75),we screened the titles and abstracts of 16 potentially eligible publications.After the irrelevant records were excluded(n=5),we screened the full texts of 11 manuscripts.Finally,5 studies were entered into the qualitative and quantitative analysis.CONCLUSION In conclusion,all the studies support the idea that vaccinations can reduce the need for antibiotic prescriptions which could potentially contribute to mitigating antibiotic resistance.However,to fully comprehend the mechanisms of antibiotic resistance,enhance treatment guidelines,and consider diverse demographic situations,further research is necessary to use evidence-based strategies to fight antibiotic misuse and resistance.

Performance Parameters:Demobilization Antibiotic Resistant Bacteria(ARB)and Carrying Genes(ARG)in Wastewater Disinfection

The UV irradiation is used for removing Antibiotic Resistant Bacteria(ARB)and Antibiotic Resistance Genes(ARG)from wastewater treatment.Bacteriophages are viruses that infect within bacteria,are recognized for bacterial control.The influence of some parameters in quantification and performance influencing of pathogen demobilization could be considered in disinfection of wastewater.The comparison of Polyvalent phage(NE1)versus Coliphage(NE4)in suppressing a bacterium Escherichia coli(NDM-1:b-lactam-resistant)with UV irradiation was observed the efficacy in reduction of cells in the disinfection and parameter process.The results with the effect of UV-C irradiation on NDM-1 infected with 1%of NE4 showed a decrease of cells from 8×10^(6)to 2×10^(5)in 60 min with UV-C dose.The NDM1(E.coli)was infected with 1%of NE4(Polyvalent Phage)under magnetic stirring for 1 h,the cells count was 8×10^(6).After 1 h in UV-C e×posure,the cells number reached 3×10^(5).The NDM1 that was e×posed in 1 h of UV-C irradiation and then was infected with 1%of NE4.Cells counting were done 24 h after this procedure.These cells were e×posed in UV-C and showed a reduction in the number of cells from 1×10^(8)to 4×10^(5)after 60 min.The results indicate that bacteriophages can mitigate bacteria species,and combined the conventional water disinfection technologies that can support the microbial safety control strategies.

Antibiotic Resistance Profile of Serotypes of Streptococcus pneumoniae Strains in Bangui, from 2017 to 2022: Case of Serotype 1

Goals: The aim of this study was to determine the antibiotic resistance profile of serotypes of Streptococcus pneumoniae strains circulating in Bangui. Methodology: A prospective and analytical analysis was carried out at the National Laboratory of Clinical Biology and Public Health from 2017 to 2022. The strains came from our study on the contribution to the study of antibiotic sensitivity of Streptococcus pneumoniae strains. The multiplex PCR test was used for its cost-effectiveness in terms of amplifiers which can be purified in order to be sequenced. It also makes it possible to detect several germs as well as their serotypes. For a PCR reaction, several elements are involved in the reaction medium or Master Mix. These are the desoxyribonucleotides (dNTPs), the magnesium ions (MgCl2) and the primers. A set of 14 primers divided into 3 classes were used. Class 1 primers served as an internal control by targeting the cpsA gene. It is a highly conserved gene found in capsular loci characterized to date. The primers of the second class were used to target specific serotypes by specific reactions (out of six possibilities). The group reaction was carried out using the primers of the third class in order to carry out an initial screening of the samples and to classify the pneumococcal isolates. Related serotypes were grouped based on the amplification of common genes. Using the technique of electrophoresis on agarose gel and an ultraviolet radiation device, the migration bands are then visualized and analyzed. The data collected had been entered into Excel 2010 and analyzed with Epi info 7. The exact Fischer chi2 test at the 5% threshold, the relative risk and its 95% confidence interval were used to compare the proportions and determine the associations. Results: 187 antibiotic-resistant strains of Streptococcus pneumoniae were collected. The average frequency of serotypes 1, 9A, 4 and untypeable identified were 43.59%, 18.18%, 18.27% and 39.57% respectively. The frequency of serotype 1 was predominant for the age group over five years old with 56.88%. The male sex was predominant with 55.08% for serotype 1. Resistance to penicillin and gentamicin for serotype 1 during this study, for the age group under 5 years old, was 77%. For serotypes 19A and 4, tetracycline resistance was predominant with 20% for the age group under 5 years. The resistance to penicillin and gentamicin of non-typeable serotypes was 33% for the age group under 5 years old. For the age group over 5 years old, resistance to erythromycin predominated at 37%. The distribution of serotypes by sex depending on antibiotic resistance was variable. There was a statistically significant association between identified serotypes and antibiotic resistance (p Conclusion: The study determined serotypes 1, serotypes 19A, serotypes 4 and non-typeable serotypes. These results would be due to the quality of vaccination or poor protection of vaccines.

Antibiotic resistance and molecular typing of clinical Staphylococcus aureus isolates from Malaysian military hospital

Objective:To determine the antibiotic resistance profile(ARP)of Staphylococcus(S.)aureus isolates and molecular typing of the methicillin-resistant S.aureus(MRSA)isolates from Tuanku Mizan Armed Forces Hospital(TMAFH),Kuala Lumpur.Methods:The ARP and presence of the pvl gene were determined for 209 S.aureus isolates from clinical specimens.Of these,123 were methicillin-susceptible S.aureus(MSSA)isolates and 86 were MRSA isolates.All MRSA isolates were characterized using SCCmec typing and spa typing.Descriptive analysis was performed to compare the demographic data with the phenotypic and genotypic variables of the S.aureus isolates.Results:No vancomycin-intermediate and-resistant S.aureus(VISA and VRSA,respectively)were detected among the study isolates.The MSSA isolates showed low resistance rates to all tested antibiotics,were commonly invasive(28/42,66.7%),and mostly harboured pvl(35/42,83.3%).Meanwhile,MRSA isolates showed high resistance to penicillin(86/86,100%),ampicillin(86/86,100%),sulbactam/ampicillin(86/86,100%),cefuroxime(81/86,94.19%),cefoperazone(76/86,88.37%),azithromycin(56/86,65.12%),and erythromycin(54/86,62.79%).The majority of MRSA isolates were of SCCmec type IVh(65/86,75.58%),spa type t032(55/85,63.95%),and grouped into spaCC-t022(66/85,77.65%).The t032 type was found to be associated with resistance traits to azithromycin and erythromycin(P<0.05).We also found several spa types that are typically associated with hospital-,community-,and livestock-associated MRSA co-existing in our MRSA population.Conclusions:This study reflected the consistent absence of VISA and VRSA and corroborated the clonal shifting of MRSA isolates in the Malaysian MRSA isolates.

Trifunctional Cu-Mesh/Cu_(2)O@FeO Nanoarrays for Highly Efficient Degradation of Antibiotic, Inactivation of Antibiotic-Resistant Bacteria, and Damage of Antibiotics Resistance Genes

Trifunctional Cu-mesh/Cu_(2)O@FeO nanoarrays heterostructure is designed and fabricated by integrating CuCu_(2)O@FeO nanoarrays onto Cu-mesh(CM)via an in situ growth and phase transformation process.It is successfully applied to efficiently mitigate the antibiotic pollution,including degradation of antibiotics,inactivation of antibiotic-resistant bacteria(ARB),and damage of antibiotics resistance genes(ARGs).Under visible-light irradiation,CM/CuCu_(2)O@FeO nanoarrays exhibit a superior degradation efficiency on antibiotics(e.g.,up to 99%in 25 min for tetracycline hydrochloride,TC),due to the generated reactive oxygen species(ROS),especially the dominant·O^(2−).It can fully inactivate E.coli(HB101)with initial number of~108 CFU mL^(−1) in 10 min,which is mainly attributed to the synergistic effects of 1D nanostructure,dissolved metal ions,and generated ROS.Meanwhile,it is able to damage ARGs after 180 min of photodegradation,including tetA(vs TC)of 3.3 log 10,aphA(vs kanamycin sulfate,KAN)of 3.4 log 10,and tnpA(vs ampicillin,AMP)of 4.4 log 10,respectively.This work explores a green way for treating antibiotic pollution under visible light.

Six-year analysis of key monitoring for bacterial strain distribution and antibiotic sensitivity in a hospital

BACKGROUND With the widespread use of antimicrobial drugs,bacterial resistance has become a significant problem,posing a serious threat to public health.The prevalence of clinical infection strains in hospitals and their drug sensitivities are key to the appropriate use of antibiotics in clinical practice.AIM To identify prevalent bacteria and their antibiotic resistance profiles in a hospital setting,thereby guiding effective antibiotic usage by clinicians.METHODS Specimens from across the institution were collected by the microbiology laboratory.The VITEK 2 compact fully automatic analyzer was used for bacterial identification and antibiotic sensitivity testing,and the WHONET5.6 software was utilized for statistical analysis.RESULTS A total of 12062 bacterial strains of key monitoring significance were detected.Staphylococcus aureus demonstrated widespread resistance to penicillin,but none of the strains were resistant to vancomycin or linezolid.Moreover,219 strains of methicillin-resistant coagulase-negative staphylococci and 110 strains of methicillin-resistant Staphylococcus aureus were detected.Enterococcus faecalis showed moderate resistance to the third-generation quinolones ciprofloxacin and levofloxacin,but its resistance to nitrofurantoin and tetracycline was low.Enterococcus faecium displayed significantly lower resistance to third-and fourthgeneration quinolones than Enterococcus faecalis.The resistance of two key monitoring strains,Escherichia coli and Klebsiella pneumoniae,to piperacillin/tazobactam was 5%-8%.However,none of the Escherichia coli and Klebsiella pneumoniae strains were resistant to meropenem.The resistance of Acinetobacter baumannii to piperacillin/sulbactam was nearly 90%.Nonetheless,the resistance to tigecycline was low,and Pseudomonas aeruginosa demonstrated minimal resistance in the antibiotic sensitivity test,maintaining a resistance of<10%to the cephalosporin antibiotics cefotetan and cefoperazone over the last 6 years.The resistance to amikacin remained at 0.2%over the past 3 years.CONCLUSION Our hospital’s overall antibiotic resistance rate was relatively stable from 2017 to 2022.The detection rates of key monitoring strains are reported quarterly and their resistance dynamics are monitored and communicated to the entire hospital,which can guide clinical antibiotic selection.

Antibiotic resistance analysis and coping strategies of helicobacter pylori

Helicobacter pylori(H.pylori)is a Gram-negative bacterium that mainly colonizes the stomach and duodenum,and it can cause gastrointestinal diseases such as gastric inflammation,peptic ulcer and gastric cancer,and eradication of H.pylori can effectively stop the occurrence and development of gastrointestinal diseases.Antibiotics are one of the main drugs used to treat H.pylori.Due to the long-term application of antibiotics,the resistance rate of H.pylori to antibiotics increases year by year,which greatly reduces the eradication rate of H.pylori and increases the difficulty of re-treatment and the economic burden of patients.In this paper,we will review three aspects of H.pylori resistance status,resistance mechanism and treatment to provide reference for the progress of H.pylori resistance research and its treatment strategy.

Antibiotic Resistance in the Uropathogenic Enterobacteria Isolated from Patients Attending General Reference Hospital (GRH) of Niamey, Niger

Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an increase in mortality as well as the cost of treatment. The present study aims to contribute to the fight against antibiotic resistance of enterobacteria. Methods: This is a prospective study from January to December, 2021 in the Microbiology laboratory of the General Reference Hospital (GRH) of Niamey including 3369 urine samples. The antibiotic resistance of enterobacteria was determined using the Viteck-2 method. Results: At least 280 strains of Enterobacteriaceae were isolated from the patient’s urine. Among these strains, Escherichia coli was the most predominant (74.64%), followed by Klebsiella pneumoniae (16.07%) and Enterobacter cloacae (7.14%) and other enterobacteria 2.15%. These Enterobacteriaceae are more common in community patients than in hospitalized patients. The average age of patients is 52 years and the age group most affected by these enterobacteria is 46 - 60 years (23.33%). The female sex is the most affected sex with (51.07%) against (48.97%) for the male sex with 1.04 as sex ratio. The hospitalization departments most affected by these enterobacteria are Nephrology (29.23%) and Endocrinology (21.54%). Up to 75% of the Enterobacteriaceae isolates show high resistance to ampicillin, amoxicillin-clavulanic acid, ticarcillin, piperacillin-tazobactam, cefoxitin, cefixime, ceftazidime, ceftriaxone, cotrimoxazole, nalidixic acid and ofloxacin. Conclusion: The high rate of antibiotic resistance among enterobacteria in urine is of concern. Only a few Enterobacteriaceae show low resistance to ertapenem, imipenem, amikacin, gentamicin, fosfomycin and nitrofurantoin. Therefore, these antibiotics are recommended as first line treatment for urinary tract infections.

Antimicrobial Stewardship: Knowledge and Attitudes of Pharmacy Staff on Antibiotic Dispensing Patterns, Use and Resistance in Benin

Background: One of the key drivers for the emergence and spread of antimicrobial resistance (AMR) is non-prudent antibiotic use, which results in selection pressure toward relevant bacteria. Pharmacy staffs have pivotal roles in facilitating the prudent use of antibiotics through antimicrobial stewardship programs. Due to limited information in Benin, this study assessed the knowledge and attitudes of pharmacy staffs on antibiotic use and resistance. Materials and Methods: This cross-sectional study was conducted among 159 pharmacy staffs using a structured questionnaire from August 2018 to December 2018 in Benin. Data analysis was done by using Stata version 13.0. Results: Of the 159 participants, 54.8% knew the definition of antibiotic therapy and 66.9% knew the definition of probabilistic antibiotic therapy. The majority (88.1%) of the participants thought that the choice of antibiotics was made according to the pathology, while 60.4% thought that it depended on the pathology and the germ involved. 49.02% of dispensers in pharmacies stated that half of the patients had requested treatment without providing a prescription at the pharmacy. The top three antibiotics that were dispensed without a prescription include amoxicillin (98.1%), cloxacillin (76.7%) and metronidazole (57.2%), all from the Access group of antibiotics. Conclusion: These results underscore the need for educational and training interventions targeting specific professional groups. There is an urgent need for regulatory measures and public awareness through improved antimicrobial stewardship to limit this practice.

Enhancing Accumulation and Penetration Efficiency of Next-Generation Antibiotics to Mitigate Antibiotic Resistance in Pseudomonas aeruginosa PAO1

This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .

Evaluation of the Microbiological Quality of Poultry Imported into Togo and the Antibiotic Resistance of Salmonella spp. Isolated

In Togo, despite the government’s efforts, food requirements in terms of animal proteins are not covered by national production and are subject to huge imports of meat products. However, the hygienic quality of these imports is not guaranteed for the consumer. The aim of this study was to estimate the frequency of unhygienically unsatisfactory imported poultry and to determine the antibiotic resistance profile of Salmonella spp. strains. A total of 285 samples of imported poultry, including 55 chicken thighs, 10 chicken backbones, 25 chicken wings, 5 whole chickens, 30 sausages, 35 chicken forequarters, 95 chicken drumsticks and 30 guinea fowl wings, were analyzed using standard AFNOR routine methods. The following germs were tested: Total Aerobic Mesophilic Flora (TAMF), Anaerobic-Sulfite-Reducing (ASR), Escherichia coli, Staphylococcus aureus and Salmonella spp. Antibiotic susceptibility testing was carried out on Salmonella spp. strains isolated using the agar disk diffusion method (CA-SFM). Results showed 100% compliance for TAMF, coagulase-positive Staphylococci and Escherichia coli. On the other hand, 3.84% and 2.46% non-compliance were recorded for ASR and Salmonella respectively. Non-compliance with hygiene rules is generally thought to be the cause of meat contamination. Seven 7 strains of Salmonella were isolated, 5 of which were of the OMA serogroup, and the other two of the OMB and HMB groups. Antibiotic susceptibility tests revealed resistance to certain beta-lactam antibiotics and quinolones, in particular: cefalexin (28.57%), cefoxitin (14.28%), cefuroxime (28.57%), ceftazidime (28.57%), ceftriaxone (28.57%) and nalidixic acid (28.57%). This result may be explained by the uncontrolled use of B-lactam and quinolone antibiotics in poultry farming. As Salmonella spp. is a pathogenic enteric bacterium that causes food-borne illness in humans, resistance to third-generation cephalosporins remains a major public health problem.

Isolation and Biological Characteristics of Bacteriophage of an Antibiotic-resistant Escherchia coli Strain

In this study, bacteriophage of an antibiotic-resistant Escherchia coil strain isolated from feces of chicken was isolated. Its host range was determined by the method of spotting sample on monolayer agar, and its lysis titer, optimal multiplicity of infection （MOI）, temperature tolerance and pH tolerance were determined by the double-layer agar plate method. The results showed that the bacteriophage had a broad host range. The biological assay demonstrated that two strains of E. coil were fully lysed and one strain of E. coil was weakly lysed by the bacteriophage. The lysis titer and MOI of the bacteriophage were 1.20×10^8 PFU/ml and 1, respec- tively. Under the optimum temperature of 40℃, the Jysis titer of the bacteriophage reached 8.90×10^9 PFU/ml; however, the bacteriophage lost its infectivity at the tem- perature of 80℃. In the pH range of 5-11, the lysis titer of the bacteriophage ranged from10^6 to 10^9 PFU/mI. Under the condition of pH 4 and 12, the bacterio- phage was invalid.

Community-acquired multidrug-resistant pneumonia,bacteraemia,and infective endocarditis:A case report

BACKGROUND The prevalence of multidrug-resistant(MDR)bacteria has increased globally,with extensive drug-resistant(XDR)bacteria posing a threat to patients.CASE SUMMARY This case report describes a young man admitted for suspected tropical fever infections who experienced rapid deterioration in health.Despite negative results for tropical fever infections,he had neutrophilic leucocytosis,acute kidney injury,and chest imaging findings suggestive of bilateral consolidations.On day two,he was diagnosed with infective endocarditis with possible rheumatic heart disease and MDR methicillin-resistant Staphylococcus aureus bacteraemia,and communityacquired pneumonia.Despite treatment with broad-spectrum antibiotics,he did not respond and succumbed to death on day five.CONCLUSION This case highlights that clinicians/public should be aware of MDR communityacquired pneumonia,bacteraemia,and endocarditis which ultimately culminate in high rates of morbidity and mortality.Early identification of pathogenic strain and prompt antibiotic treatment are a mainstay for the management and prevention of early fatalities.Simultaneously,route cause analysis of communityacquired MDR/XDR pathogens is a global need.

Success of susceptibility-guided eradication of Helicobacter pylori in a region with high secondary clarithromycin and levofloxacin resistance rates

BACKGROUND Resistance to clarithromycin(CLA)and levofloxacin(LFX)of Helicobacter pylori(H.pylori)is increasing in severity,and successful eradication is essential.Presently,the eradication success rate has greatly declined,leaving a large number of patients with previous treatment histories.AIM To investigate secondary resistance rates,explore risk factors for antibiotic resistance,and assess the efficacy of susceptibility-guided therapy.METHODS We recruited 154 subjects positive for Urea Breath Test who attended The First Affiliated Hospital of China Medical University between July 2022 and April 2023.Participants underwent a string test after an overnight fast.The gastric juice was obtained and transferred to vials containing storage solution.Subsequently,DNA extraction and the specific DNA amplification were performed using quantitative polymerase chain reaction(qPCR).Demographic information was also analyzed as part of the study.Based on these results,the participants were administered susceptibility-guided treatment.Efficacy was compared with that of the empiric treatment group.RESULTS A total of 132 individuals tested positive for the H.pylori ureA gene by qPCR technique.CLA resistance rate reached a high level of 82.6%(n=109),LFX resistance rate was 69.7%(n=92)and dual resistance was 62.1%(n=82).Gastric symptoms[odds ratio(OR)=2.782;95%confidence interval(95%CI):1.076-7.194;P=0.035]and rural residence(OR=5.152;95%CI:1.407-18.861;P=0.013)were independent risk factors for secondary resistance to CLA and LFX,respectively.A total of 102 and 100 individuals received susceptibility-guided therapies and empiric treatment,respectively.The antibiotic susceptibility-guided treatment and empiric treatment groups achieved successful eradication rates of 75.5%(77/102)and 59.0%(59/411)by the intention-to-treat(ITT)analysis and 90.6%(77/85)and 70.2%(59/84)by the per-protocol(PP)analysis,respectively.The eradication rates of these two treatment strategies were significantly different in both ITT(P=0.001)and PP(P=0.012)analyses.CONCLUSION H.pylori presented high secondary resistance rates to CLA and LFX.For patients with previous treatment failures,treatments should be guided by antibiotic susceptibility tests or regional antibiotic resistance profile.

Effect of acacetin on inhibition of apoptosis in Helicobacter pyloriinfected gastric epithelial cell line

BACKGROUND Helicobacter pylori(H.pylori)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric carcinoma.Prompt eradication of H.pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer.Acacetin,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various domains.Nevertheless,the impact and underlying mechanisms of action of acacetin on H.pylori-infected gastric mucosal epithelial cells remain unclear.AIM To explore the defensive effects of acacetin on apoptosis in H.pylori-infected GES-1 cells and to investigate the underlying mechanisms.METHODS GES-1 cells were treated with H.pylori and acacetin in vitro.Cell viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot analysis.RESULTS H.pylori infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 expression.Conversely,acacetin treatment enhanced cell viability,mitigated apoptosis induced by H.pylori infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3.CONCLUSION Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H.pylori-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.