Aim： To study the influence of enterococci on human sperm membrane in vitro. Methods： Ejaculated human sperm were artificially infected with β-hemolytic or non-β-hemolytic enterococci at the bacteria： sperm ratio...Aim： To study the influence of enterococci on human sperm membrane in vitro. Methods： Ejaculated human sperm were artificially infected with β-hemolytic or non-β-hemolytic enterococci at the bacteria： sperm ratio of 50：1 at 37℃. Sperm membrane integrity was examined after incubation for 1, 3 and 5 h by hypoosmotic swelling （HOS） test and electron microscopy. Results： Sperm infected with β-hemolytic enterococci had lower HOS scores compared with non-β-hemolytic strains or uninfected control （P 〈 0.01）. The HOS test scores of sperm infected with β-hemolytic enterococci increased in the presence of phosphatidylcholine, an inhibitor of hemolysin. Non-β-hemolytic strains showed no significant difference in swelling rate, compared with the control group （P 〉 0.05）. It was shown by electron microscopy that β-hemolytic enterococci caused significant rupture of human sperm membrane. Conclusion： β-hemolytic enterococci caused human sperm membrane injury, and might be mediated by the hemolysin of enterococci.展开更多
Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistenc...Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistence in tropical marine and fresh waters. For the clinical and epidemic strains tested, it took 2.38 ± 0.45 days for a 1-log reduction (T90) in marine water. A higher T90 average of 2.51 ± 0.08 was observed for the commensal and environmental strains. Generally, lower T90 values of 2.14 ± 0.26 and 2.15 ± 0.16 days respectively were observed for hospital and community acquired enterococci strains in fresh water mesocosms subjected to tropical ambient temperature. Beach water enterococci and enterococci recovered from faeces of humans survived for up to 20 days and 23 days respectively in fresh and marine waters. The epidemic strain, MMH594, an esp-positive clinical bacteremia isolate that previously caused multiple infections in a hospital ward outbreak fares favourably well in tropical marine and fresh aquatic environments. For enterococci, the decay rate was approximately 13% higher in fresh water than was observed for marine water. On the contrary, for E. coli, the decay rate was approximately 17% lower in fresh water than was observed in marine water. Generally, the whole, the population trends of E. coli and enterococci in fresh and marine water mesocosms did not reveal any evidence of growth. Our findings suggest that potentially pathogenic bacteria can resume active growth after three weeks of being harboured by the reservoir-beach sand and still pose threat to public health.展开更多
The emergence of daptomycin non-susceptible enterococci(DNSE) poses both treatment and infection control challenges.Clinicians should be vigilant that DNSE may be isolated from patients with or without(de novo DNSE) p...The emergence of daptomycin non-susceptible enterococci(DNSE) poses both treatment and infection control challenges.Clinicians should be vigilant that DNSE may be isolated from patients with or without(de novo DNSE) prior use of daptomycin.Recent epidemiological data suggest the presence of a community reservoir for DNSE which may be associated with environmental,foodborne and agricultural exposures.The mechanisms of nonsusceptibility to daptomycin have not been well characterized and may not parallel those for Staphylococcus aureus.The identification of daptomycin resistance genes in anaerobes,in farm animals and in an ecosystem that has been isolated for million years,suggest that the environmental reservoir for de novo DNSE may be larger than previously thought.Herein,the limited available scientific evidence regarding the possible origin of de novo DNSE is discussed.The current existing evidence is not sufficient to draw firm conclusions on the origin of DNSE.Further studies to determine the mechanisms of de novo daptomycin nonsusceptibility among enterococci are needed.展开更多
This study aims to generate data which can be used as a potential starting point for the updating of the Philippine Water Quality Criteria and the determination of the true impact of land use to the fecal contaminatio...This study aims to generate data which can be used as a potential starting point for the updating of the Philippine Water Quality Criteria and the determination of the true impact of land use to the fecal contamination of the Pampanga River Basin (PRB), the largest subwatershed of Manila Bay. Levels of fecal indicator bacteria (FIB) were determined in the selected tributaries of the PRB, representing three land use categories, namely, the forest/woodland (control), agricultural and residential lands. FIB were quantified in order to investigate the potential contribution of the selected areas in the fecal contamination of the PRB. The study was conducted in 2021 covering March, May, June, July, and September to represent the dry (March and May) and wet (June, July, and September) seasons. Counts of FIB, namely thermotolerant coliform, E. coli, and enterococci were qualitatively correlated with the results of the ocular survey and key informant interview based on known fecal contributors and their relevant rainfall data. FIB counts of water bodies in the selected agricultural and residential land use categories had Geometric Mean (GM) counts that are statistically greater than those of bodies of water near the representative forest/woodland (control), and exceeded the acceptable GM limits for all FIB, regardless of the season. Notably, the GM values recorded for the waters near the selected forest/woodland (control) passed the water quality criteria for all measured FIB parameters for both seasons. Furthermore, enterococci levels in the control site were statistically lower during the wet season. These initial findings suggest that agricultural and residential land use categories could be major contributors to the unacceptable water quality of tributaries of the Pampanga River Basin. The prevalence of thermotolerant coliforms and E. coli was noted regardless of rainfall and land use, indicating these FIB may not be adequate as water quality indicators. With their ability to survive and persist in fecally contaminated sediments in water bodies and in nutrient-poor environments, enterococci could be more definitive indicators of fecal contamination and microbiological quality of environmental waters.展开更多
Introduction: Enterococci are members of the healthy human intestinal flora, but are also leading causes of highly antibiotic-resistant infections. Serious enterococcal infections are often difficult to treat since th...Introduction: Enterococci are members of the healthy human intestinal flora, but are also leading causes of highly antibiotic-resistant infections. Serious enterococcal infections are often difficult to treat since the organisms have a tremendous capacity to acquire resistance to penicillin, high concentration of aminoglycoside & vancomycin. Careful review of in vitro susceptibility data is required to treat infections caused by MDR Enterococci. Therefore we conducted the study to find out prevalence of MDR Enterococci. Aims & Objectives: To study the prevalence of Vancomycin resistance, High Level Streptomycin Resistance (HLSR) & High Level Gentamicin Resistance (HLGR) in different enterococcal isolates. Materials & Methods: Total 180 enterococcal isolates were studied. Identification was done by conventional biochemical methods. Antibiotic susceptibility testing was done by Kirby-Bauer disc diffusion method on Mueller–Hinton agar and results were interpreted as per CLSI guidelines. HLSR & HLGR was determined by disc diffusion method using high level Gentamicin disc (120 μg) & Streptomycin (300 μg) discs. Minimum inhibitory concentration (MIC) determination for Vancomycin was done by vancomycin E test strips. Results: Total 180 entetococcal isolates were studied. E. faecalis was 60%, E. faecium was 32.2%, E. durans and E. raffinosus were 4.4% & 3.3% respectively. Enterococcus fecium showed resistance in high percentage as compared to E. faecalis. 15 isolates were found to be vancomycin resistant. Conclusion: Resistance to aminoglycoside is of great concern. Regular screening of enterococcal isolates for vancomycin resistance detection should be implemented. It is very important to implement infection control measures, screening of health care workers, surveillance cultures in intensive care units which can control spread of multidrug resistant enterococci.展开更多
Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens,thereby exacerbating infections.However,there are few effective therapeutic strategies to prevent and intervene in enter...Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens,thereby exacerbating infections.However,there are few effective therapeutic strategies to prevent and intervene in enterococci-mediated polymicrobial infections.Here,we find that enterococci at high density drive the expansion and pathogenicity of enteric Salmonella enterica serotype Typhimurium(S.Tm).Subsequently,we show that the driving role of enterococci in such infections is counteracted by dietary coumarin glycosides in vivo.Enterococci,which are tolerant of iron-deficient environments,produceβ-glucosidases to hydrolyze coumarin glycosides into bioactive aglycones,inhibiting S.Tm growth and ameliorating the severity of S.Tm-induced symptoms by inducing iron limitation.Overall,we demonstrate that coumarin glycosides as a common diet effectively reverse enterococci-facilitated enteric infections,providing an alternative intervention to combat polymicrobial infections.展开更多
Objective:To investigate the species prevalence of Enterococcus with their antimicrobial resistance pattern from patients of Dhaka Medical College Hospital.Methods:Samples were cultured and Enterococcus species were i...Objective:To investigate the species prevalence of Enterococcus with their antimicrobial resistance pattern from patients of Dhaka Medical College Hospital.Methods:Samples were cultured and Enterococcus species were identified by conventional biochemical tests as well as PCR by using species specific primers for Enterococcus faecalis(E.faecalis)and Enterococcus faecium(E.faecium).For isolation of vancomycin resistant enterococci,minimum inhibitory concentration of vancomycin and PCR was done to detect vanA and vanB genes.Results:A total of 16 enterococci were isolated from 300 urine and 200 wound swab samples(15 from urine and 1 from wound swab)from July 2011 to June 2012.Enterococci were the third most common organism(8.47%)from urine after Escherichia coli(63.28%)and Enterobacter(11.87%).Out of 16 enterococci,10(62.5%)were E.faecalis,4(25%)were E.faecium and 2(12.5%)were other species.All the enterococci(100%)were sensitive to vancomycin and linezolid.Most of the strains were resistant to ciprofloxacin and azithromycin(87.5%),gentamycin(81.25%),ceftriaxone(75%),amoxiclav(31.25%)and imipenem(25%).E.faecium was more resistant than E.faecalis to azithromycin(100%),ciprofloxacin(100%),amoxiclav(75%)and imipenem(50%).No vancomycin resistant enterococci were identified and the range of minimum inhibitory concentration for vancomycin was 1-4μg/mL.None of the enterococci were positive for vanA and vanB genes.Conclusions:The presence of multidrug resistant enterococci should be considered as danger alarm for serious enterococcal infections and further study in large scale is needed.展开更多
Background Nosocomial infection caused by methicillin-resistant Staphylococcus aureus （MRSA） and vancomycin-resistant enterococci （VRE） could lead to increased morbidity and mortality. In 2006, VRE nosocomial spre...Background Nosocomial infection caused by methicillin-resistant Staphylococcus aureus （MRSA） and vancomycin-resistant enterococci （VRE） could lead to increased morbidity and mortality. In 2006, VRE nosocomial spread became a reality in our hospital since the first VRE nosocomial infection in 2003. Little is known about the prevalence of coexistence with VRE and MRSA in the patients. The primary objective of the study was to identify the molecular characteristics of epidemic MRSA clones in our hospital and the prevalence of the coexistence with MRSA and VRE in same patients during the 2-year period, 2006-2007. Methods The clinical features, laboratory test results, and therapeutic outcomes of 129 cases who isolated MRSA collected from January 2006 to December 2007 were retrospectively analyzed. Polymerase chain reaction （PCR） was used to determine mecA-femB type and staphylococcal cassette chromosome mec （SCCmec） type. All the participants were screened for clinical and microbiological data to identify the coexistence of VRE strains with MRSA. Results One hundred and twenty-nine MRSA isolates were included in the study： 71 （55%） from the intensive care unit, 35 （27.2%） from the surgical wards and 23 （17.8%） from the medical wards. The most frequent source of isolation of MRSA was sputum （76.7%）. From seven patients we isolated MRSA and VRE （E. faecium） simultaneously during their inpatient stay. One hundred and twenty-seven （127/129, 98.4%） MRSA isolates harboured SCCmec type Ⅲ, only 2 MRSA strains contained SCCmec type Ⅱ. All of the 129 MRSA isolates remained sensitive to vancomycin, teicoplanin and linezolid. Higher sensitivity rates were noted for chloramphenicol 99.2% （128/129）. Only 20.2% （26/129） of the MRSA isolates were sensitive to rifampin. All isolates presented resistance to multiple antimicrobial agents with high minimum inhibitory concentrations （MICs）, including： β-Iactams （penicillin, oxacillin, cefoxitin, and cefazolin）, tetracycline, erythromycin, gentamicin, and quinolones （ciprofloxacin, levofloxacin, and moxifloxacin）. Conclusions The predominant MRSA clone at Beijing Chaoyang Hospital from 2006 to 2007 had the type Ⅲ SCCmec element. All of the MRSA isolates were multiresistant to antimicrobial agents. Emergence of coexistence of MRSA and VRE in the same patient was not rare. Physicians should pay more attention to infections resulting from MRSA and VRE. Aggressive infection control measures should be taken to prevent the transmission of the multidrug resistance organism.展开更多
The prevalence and transmission of vancomycin-resistant Enterococcus(VRE)in enterococci being as probiotics has been neglected in the scientific literature.The application of enterococci in feed,food and health produc...The prevalence and transmission of vancomycin-resistant Enterococcus(VRE)in enterococci being as probiotics has been neglected in the scientific literature.The application of enterococci in feed,food and health products may cause VRE transmission through the food chain.This study evaluated phenotypic resistance of Enterococcus species to 20 antibiotics along a pork production chain from feed to food.It also assessed the genetic diversity of Enterococcus faecium isolates.A total of 510 samples(feed,n=70;swine manure,n=400;swine carcasses,n=20,and retail pork,n=20)were collected in Beijing,China.A total of 328 enterococci isolates with 275 E.faecium and 53 Enterococcus faecalis were identified using 16 S rRNA.Antimicrobial susceptibility to all enterococci isolates was conducted using the KeB method for 20 antibiotics from 9 categories.Multilocus sequence typing(MLST)was conducted on the E.faecium isolates to survey the dissemination of enterococci in the pig industry.The results showed that only 26 enterococci isolates were sensitive to the 20 antibiotics,while half of the isolates(164/328)had acquired multi-drug resistance.The resistant rate to furazolidone was 68.60%,followed by 42.99%to tetracycline.One vancomycin-resistant E.faecium isolates were isolated from feed origin and 2 from manure origin,with minimum inhibitory concentrations to vancomycin of 1,024,64,and 64 mg/mL,respectively.The MLST outcomes showed that the 275 E.faecium isolates belonged to 11 sequence types(ST)including ST40,ST60,ST94,ST160,ST178,ST296,ST361,ST695,ST726,ST812 and ST1014.The ST of the feedsourced VRE was ST1014,while the 2 manure-sourced VRE was ST69.ST1014 evolved from ST78,which was the dominant clonal complex in most cities of China,leading to the spreading of VRE.These findings revealed the potential safety hazards of commercial probiotic enterococci in China and showed that there is a risk of the VRE horizontally transferring from feed to food.展开更多
Background： Vancomycin-resistant enterococci （VRE） are a major and emerging hospital-acquired pathogen associated with high mortality, particularly among the critically ill and Intensive Care Units （ICUs） patient...Background： Vancomycin-resistant enterococci （VRE） are a major and emerging hospital-acquired pathogen associated with high mortality, particularly among the critically ill and Intensive Care Units （ICUs） patients. This study aimed to determine the prevalence and demographic and clinical characteristics of VRE among patients admitted to a university hospital in Riyadh, Saudi Arabia. Methods： A study was conducted during the period from September 2014 to November 2015 at King Khalid University Hospital, a tertiary care hospital in Riyadh, Saudi Arabia, including in-patients with VRE infection. Data were collected using laboratory results and the medical records of admitted patients and were analyzed using SPSS version 19.0 statistical software. Results： In a one-year period, 231 enterococci were isolated from blood, urine, exudates, sputum, stool, and body fluid. There were 191 （82.7%） vancomycin-sensitive enterococci （VSE） and 40 （I 7.3%） isolates were VRE. The Enterococcus species included E.faecalis 168 （72.7%）, E.faecium, 53 （22.8%） E. gallinarum 5 （2.2%）, and E. avium 5 （2.2%）. VRE were more significant from blood specimens （P 〈 0.000 I） while VSE were significantly more predominant from urine specimens （P 〈 0.0001）. VRE were more commonly isolated from patients in ICUs and oncology unit （P = 0.0151 and P 〈 0.001, respectively） while VSE were more predominant in the medical and surgical areas （P = 0.0178 and P = 0.0178, respectively）. Conclusions： This study highlights the high prevalence of VRE in the hospital and the association of enterococcal infections with high-risk areas and oncology units, which warrant more studies looking for better management of these infections.展开更多
目的:系统评价氯己定全身擦浴对重症监护室(ICU)病人多重耐药菌感染的预防效果。方法:检索the Cochrane Library、PubMed、Web of Science、EMbase、中国知网、万方数据库、维普数据库、中国生物医学文献数据库中关于氯己定全身擦浴预防...目的:系统评价氯己定全身擦浴对重症监护室(ICU)病人多重耐药菌感染的预防效果。方法:检索the Cochrane Library、PubMed、Web of Science、EMbase、中国知网、万方数据库、维普数据库、中国生物医学文献数据库中关于氯己定全身擦浴预防ICU病人多重耐药菌感染效果的中英文文献。由2名研究者根据纳入与排除标准独立筛选文献、质量评价及提取资料,采用Stata 16.0软件进行Meta分析。结果:最终纳入11项研究共23090例病人。Meta分析结果显示,与常规温水或肥皂水擦浴比较,氯己定能降低ICU病人多重耐药菌感染(OR=0.770,P<0.001)。其中氯己定全身擦浴能降低耐万古霉素肠球菌(VRE)(OR=0.664,P=0.004)及耐碳青霉烯类铜绿假单胞菌(CRPA)(OR=0.442,P=0.034)的感染发生风险,但不能降低耐甲氧西林金黄色葡萄球菌(MRSA)(OR=0.852,P=0.193)及耐碳青霉烯类鲍曼不动杆菌(CRAB)的感染发生风险(OR=0.888,P=0.537)。结论:现有证据显示,氯己定全身擦浴能降低ICU病人多重耐药菌感染,但仅对部分耐药菌有效。展开更多
基金Acknowledgment This work was supported by grants from Natural Science Foundation of Fujian Province, China （No. C0510008） and Science ＆ Technology Development Plan of Fujian Province, China （No. C0101080）.
文摘Aim： To study the influence of enterococci on human sperm membrane in vitro. Methods： Ejaculated human sperm were artificially infected with β-hemolytic or non-β-hemolytic enterococci at the bacteria： sperm ratio of 50：1 at 37℃. Sperm membrane integrity was examined after incubation for 1, 3 and 5 h by hypoosmotic swelling （HOS） test and electron microscopy. Results： Sperm infected with β-hemolytic enterococci had lower HOS scores compared with non-β-hemolytic strains or uninfected control （P 〈 0.01）. The HOS test scores of sperm infected with β-hemolytic enterococci increased in the presence of phosphatidylcholine, an inhibitor of hemolysin. Non-β-hemolytic strains showed no significant difference in swelling rate, compared with the control group （P 〉 0.05）. It was shown by electron microscopy that β-hemolytic enterococci caused significant rupture of human sperm membrane. Conclusion： β-hemolytic enterococci caused human sperm membrane injury, and might be mediated by the hemolysin of enterococci.
文摘Culturable faecal coliform, epidemic, clinical, faecal and recreational beach enterococci strains possessing putative virulence genes were enumerated over the course of 5 weeks to comparatively assess their persistence in tropical marine and fresh waters. For the clinical and epidemic strains tested, it took 2.38 ± 0.45 days for a 1-log reduction (T90) in marine water. A higher T90 average of 2.51 ± 0.08 was observed for the commensal and environmental strains. Generally, lower T90 values of 2.14 ± 0.26 and 2.15 ± 0.16 days respectively were observed for hospital and community acquired enterococci strains in fresh water mesocosms subjected to tropical ambient temperature. Beach water enterococci and enterococci recovered from faeces of humans survived for up to 20 days and 23 days respectively in fresh and marine waters. The epidemic strain, MMH594, an esp-positive clinical bacteremia isolate that previously caused multiple infections in a hospital ward outbreak fares favourably well in tropical marine and fresh aquatic environments. For enterococci, the decay rate was approximately 13% higher in fresh water than was observed for marine water. On the contrary, for E. coli, the decay rate was approximately 17% lower in fresh water than was observed in marine water. Generally, the whole, the population trends of E. coli and enterococci in fresh and marine water mesocosms did not reveal any evidence of growth. Our findings suggest that potentially pathogenic bacteria can resume active growth after three weeks of being harboured by the reservoir-beach sand and still pose threat to public health.
文摘The emergence of daptomycin non-susceptible enterococci(DNSE) poses both treatment and infection control challenges.Clinicians should be vigilant that DNSE may be isolated from patients with or without(de novo DNSE) prior use of daptomycin.Recent epidemiological data suggest the presence of a community reservoir for DNSE which may be associated with environmental,foodborne and agricultural exposures.The mechanisms of nonsusceptibility to daptomycin have not been well characterized and may not parallel those for Staphylococcus aureus.The identification of daptomycin resistance genes in anaerobes,in farm animals and in an ecosystem that has been isolated for million years,suggest that the environmental reservoir for de novo DNSE may be larger than previously thought.Herein,the limited available scientific evidence regarding the possible origin of de novo DNSE is discussed.The current existing evidence is not sufficient to draw firm conclusions on the origin of DNSE.Further studies to determine the mechanisms of de novo daptomycin nonsusceptibility among enterococci are needed.
文摘This study aims to generate data which can be used as a potential starting point for the updating of the Philippine Water Quality Criteria and the determination of the true impact of land use to the fecal contamination of the Pampanga River Basin (PRB), the largest subwatershed of Manila Bay. Levels of fecal indicator bacteria (FIB) were determined in the selected tributaries of the PRB, representing three land use categories, namely, the forest/woodland (control), agricultural and residential lands. FIB were quantified in order to investigate the potential contribution of the selected areas in the fecal contamination of the PRB. The study was conducted in 2021 covering March, May, June, July, and September to represent the dry (March and May) and wet (June, July, and September) seasons. Counts of FIB, namely thermotolerant coliform, E. coli, and enterococci were qualitatively correlated with the results of the ocular survey and key informant interview based on known fecal contributors and their relevant rainfall data. FIB counts of water bodies in the selected agricultural and residential land use categories had Geometric Mean (GM) counts that are statistically greater than those of bodies of water near the representative forest/woodland (control), and exceeded the acceptable GM limits for all FIB, regardless of the season. Notably, the GM values recorded for the waters near the selected forest/woodland (control) passed the water quality criteria for all measured FIB parameters for both seasons. Furthermore, enterococci levels in the control site were statistically lower during the wet season. These initial findings suggest that agricultural and residential land use categories could be major contributors to the unacceptable water quality of tributaries of the Pampanga River Basin. The prevalence of thermotolerant coliforms and E. coli was noted regardless of rainfall and land use, indicating these FIB may not be adequate as water quality indicators. With their ability to survive and persist in fecally contaminated sediments in water bodies and in nutrient-poor environments, enterococci could be more definitive indicators of fecal contamination and microbiological quality of environmental waters.
文摘Introduction: Enterococci are members of the healthy human intestinal flora, but are also leading causes of highly antibiotic-resistant infections. Serious enterococcal infections are often difficult to treat since the organisms have a tremendous capacity to acquire resistance to penicillin, high concentration of aminoglycoside & vancomycin. Careful review of in vitro susceptibility data is required to treat infections caused by MDR Enterococci. Therefore we conducted the study to find out prevalence of MDR Enterococci. Aims & Objectives: To study the prevalence of Vancomycin resistance, High Level Streptomycin Resistance (HLSR) & High Level Gentamicin Resistance (HLGR) in different enterococcal isolates. Materials & Methods: Total 180 enterococcal isolates were studied. Identification was done by conventional biochemical methods. Antibiotic susceptibility testing was done by Kirby-Bauer disc diffusion method on Mueller–Hinton agar and results were interpreted as per CLSI guidelines. HLSR & HLGR was determined by disc diffusion method using high level Gentamicin disc (120 μg) & Streptomycin (300 μg) discs. Minimum inhibitory concentration (MIC) determination for Vancomycin was done by vancomycin E test strips. Results: Total 180 entetococcal isolates were studied. E. faecalis was 60%, E. faecium was 32.2%, E. durans and E. raffinosus were 4.4% & 3.3% respectively. Enterococcus fecium showed resistance in high percentage as compared to E. faecalis. 15 isolates were found to be vancomycin resistant. Conclusion: Resistance to aminoglycoside is of great concern. Regular screening of enterococcal isolates for vancomycin resistance detection should be implemented. It is very important to implement infection control measures, screening of health care workers, surveillance cultures in intensive care units which can control spread of multidrug resistant enterococci.
基金supported by the National Key Research and Development Program of China(2022YFD1801600)National Natural Science Foundation of China(32230106).
文摘Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens,thereby exacerbating infections.However,there are few effective therapeutic strategies to prevent and intervene in enterococci-mediated polymicrobial infections.Here,we find that enterococci at high density drive the expansion and pathogenicity of enteric Salmonella enterica serotype Typhimurium(S.Tm).Subsequently,we show that the driving role of enterococci in such infections is counteracted by dietary coumarin glycosides in vivo.Enterococci,which are tolerant of iron-deficient environments,produceβ-glucosidases to hydrolyze coumarin glycosides into bioactive aglycones,inhibiting S.Tm growth and ameliorating the severity of S.Tm-induced symptoms by inducing iron limitation.Overall,we demonstrate that coumarin glycosides as a common diet effectively reverse enterococci-facilitated enteric infections,providing an alternative intervention to combat polymicrobial infections.
文摘Objective:To investigate the species prevalence of Enterococcus with their antimicrobial resistance pattern from patients of Dhaka Medical College Hospital.Methods:Samples were cultured and Enterococcus species were identified by conventional biochemical tests as well as PCR by using species specific primers for Enterococcus faecalis(E.faecalis)and Enterococcus faecium(E.faecium).For isolation of vancomycin resistant enterococci,minimum inhibitory concentration of vancomycin and PCR was done to detect vanA and vanB genes.Results:A total of 16 enterococci were isolated from 300 urine and 200 wound swab samples(15 from urine and 1 from wound swab)from July 2011 to June 2012.Enterococci were the third most common organism(8.47%)from urine after Escherichia coli(63.28%)and Enterobacter(11.87%).Out of 16 enterococci,10(62.5%)were E.faecalis,4(25%)were E.faecium and 2(12.5%)were other species.All the enterococci(100%)were sensitive to vancomycin and linezolid.Most of the strains were resistant to ciprofloxacin and azithromycin(87.5%),gentamycin(81.25%),ceftriaxone(75%),amoxiclav(31.25%)and imipenem(25%).E.faecium was more resistant than E.faecalis to azithromycin(100%),ciprofloxacin(100%),amoxiclav(75%)and imipenem(50%).No vancomycin resistant enterococci were identified and the range of minimum inhibitory concentration for vancomycin was 1-4μg/mL.None of the enterococci were positive for vanA and vanB genes.Conclusions:The presence of multidrug resistant enterococci should be considered as danger alarm for serious enterococcal infections and further study in large scale is needed.
基金The study was supported by-grants from the National Natural Science Foundation of China （No. 30870094/C010603） and the Beijing Science ＆ Technology （No. Z08050700020801）.
文摘Background Nosocomial infection caused by methicillin-resistant Staphylococcus aureus （MRSA） and vancomycin-resistant enterococci （VRE） could lead to increased morbidity and mortality. In 2006, VRE nosocomial spread became a reality in our hospital since the first VRE nosocomial infection in 2003. Little is known about the prevalence of coexistence with VRE and MRSA in the patients. The primary objective of the study was to identify the molecular characteristics of epidemic MRSA clones in our hospital and the prevalence of the coexistence with MRSA and VRE in same patients during the 2-year period, 2006-2007. Methods The clinical features, laboratory test results, and therapeutic outcomes of 129 cases who isolated MRSA collected from January 2006 to December 2007 were retrospectively analyzed. Polymerase chain reaction （PCR） was used to determine mecA-femB type and staphylococcal cassette chromosome mec （SCCmec） type. All the participants were screened for clinical and microbiological data to identify the coexistence of VRE strains with MRSA. Results One hundred and twenty-nine MRSA isolates were included in the study： 71 （55%） from the intensive care unit, 35 （27.2%） from the surgical wards and 23 （17.8%） from the medical wards. The most frequent source of isolation of MRSA was sputum （76.7%）. From seven patients we isolated MRSA and VRE （E. faecium） simultaneously during their inpatient stay. One hundred and twenty-seven （127/129, 98.4%） MRSA isolates harboured SCCmec type Ⅲ, only 2 MRSA strains contained SCCmec type Ⅱ. All of the 129 MRSA isolates remained sensitive to vancomycin, teicoplanin and linezolid. Higher sensitivity rates were noted for chloramphenicol 99.2% （128/129）. Only 20.2% （26/129） of the MRSA isolates were sensitive to rifampin. All isolates presented resistance to multiple antimicrobial agents with high minimum inhibitory concentrations （MICs）, including： β-Iactams （penicillin, oxacillin, cefoxitin, and cefazolin）, tetracycline, erythromycin, gentamicin, and quinolones （ciprofloxacin, levofloxacin, and moxifloxacin）. Conclusions The predominant MRSA clone at Beijing Chaoyang Hospital from 2006 to 2007 had the type Ⅲ SCCmec element. All of the MRSA isolates were multiresistant to antimicrobial agents. Emergence of coexistence of MRSA and VRE in the same patient was not rare. Physicians should pay more attention to infections resulting from MRSA and VRE. Aggressive infection control measures should be taken to prevent the transmission of the multidrug resistance organism.
基金the National Key Research and Development Plan of China from People's Republic of China Ministry of Science together with Technology(grant number 2017YFD0500500,2017YFD0502200)as well as the Program for Shaanxi Science&Technology from Shaanxi Provincial Science together with Technology Department(grant number 2018ZDCXLNY-02-01,2018ZDXM-NY-051,2017TSCXL-NY-04-04).
文摘The prevalence and transmission of vancomycin-resistant Enterococcus(VRE)in enterococci being as probiotics has been neglected in the scientific literature.The application of enterococci in feed,food and health products may cause VRE transmission through the food chain.This study evaluated phenotypic resistance of Enterococcus species to 20 antibiotics along a pork production chain from feed to food.It also assessed the genetic diversity of Enterococcus faecium isolates.A total of 510 samples(feed,n=70;swine manure,n=400;swine carcasses,n=20,and retail pork,n=20)were collected in Beijing,China.A total of 328 enterococci isolates with 275 E.faecium and 53 Enterococcus faecalis were identified using 16 S rRNA.Antimicrobial susceptibility to all enterococci isolates was conducted using the KeB method for 20 antibiotics from 9 categories.Multilocus sequence typing(MLST)was conducted on the E.faecium isolates to survey the dissemination of enterococci in the pig industry.The results showed that only 26 enterococci isolates were sensitive to the 20 antibiotics,while half of the isolates(164/328)had acquired multi-drug resistance.The resistant rate to furazolidone was 68.60%,followed by 42.99%to tetracycline.One vancomycin-resistant E.faecium isolates were isolated from feed origin and 2 from manure origin,with minimum inhibitory concentrations to vancomycin of 1,024,64,and 64 mg/mL,respectively.The MLST outcomes showed that the 275 E.faecium isolates belonged to 11 sequence types(ST)including ST40,ST60,ST94,ST160,ST178,ST296,ST361,ST695,ST726,ST812 and ST1014.The ST of the feedsourced VRE was ST1014,while the 2 manure-sourced VRE was ST69.ST1014 evolved from ST78,which was the dominant clonal complex in most cities of China,leading to the spreading of VRE.These findings revealed the potential safety hazards of commercial probiotic enterococci in China and showed that there is a risk of the VRE horizontally transferring from feed to food.
文摘Background： Vancomycin-resistant enterococci （VRE） are a major and emerging hospital-acquired pathogen associated with high mortality, particularly among the critically ill and Intensive Care Units （ICUs） patients. This study aimed to determine the prevalence and demographic and clinical characteristics of VRE among patients admitted to a university hospital in Riyadh, Saudi Arabia. Methods： A study was conducted during the period from September 2014 to November 2015 at King Khalid University Hospital, a tertiary care hospital in Riyadh, Saudi Arabia, including in-patients with VRE infection. Data were collected using laboratory results and the medical records of admitted patients and were analyzed using SPSS version 19.0 statistical software. Results： In a one-year period, 231 enterococci were isolated from blood, urine, exudates, sputum, stool, and body fluid. There were 191 （82.7%） vancomycin-sensitive enterococci （VSE） and 40 （I 7.3%） isolates were VRE. The Enterococcus species included E.faecalis 168 （72.7%）, E.faecium, 53 （22.8%） E. gallinarum 5 （2.2%）, and E. avium 5 （2.2%）. VRE were more significant from blood specimens （P 〈 0.000 I） while VSE were significantly more predominant from urine specimens （P 〈 0.0001）. VRE were more commonly isolated from patients in ICUs and oncology unit （P = 0.0151 and P 〈 0.001, respectively） while VSE were more predominant in the medical and surgical areas （P = 0.0178 and P = 0.0178, respectively）. Conclusions： This study highlights the high prevalence of VRE in the hospital and the association of enterococcal infections with high-risk areas and oncology units, which warrant more studies looking for better management of these infections.
