AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, labor...AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm<sup>3</sup>. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.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
Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective ...Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective cohort of patients colonized and/or infected with Gram negative bacteria was conducted at two adult ICUs from hospitals in Brazil (April 2012 to February 2013). Nasal, groin and perineum swabs were performed. Samples were incubated on MacConkey and cetrimide agar (48 h at 37℃) and identification tests (Vitek-BioMérieux), antibiogram (Bauer-Kirby method), Carba NP test, Polymerase Chain Reaction (PCR) and sequencing were performed. The patterns of resistant microorganisms were compared by rep-PCR (Diversilab). Results: There were 53 cases of colonization. In these cases, we identified imipenem-resistant Acinetobacter baumannii (51%), Pseudomonas aeruginosa (32%), Klebsiella pneumoniae ESBL (38%) or imipenem resistant (5.6%). The use of antimicrobials and medical devices were related to colonization (p The resistance patterns expressed by Klebsiella pneumoniae were ESBL (CTX-M, SHV e TEM) and KPC2. A verified profile of Acinetobacter baumannii was related to OXA-23 and OXA-253 (OXA-143 variant). The profiles ESBL and KPC2 expressed by Klebsiella pneumoniae were distributed between the both ICUs. The distribution of OXA-23 and OXA-253 was verified only in one ICU. The similarity of strains ranged from 80% to 95%, highlighting the horizontal transference of these microorganisms.展开更多
The mounting threat of antibiotic-resistant bacterial infections has made it imperative to develop innovative antibacterial strategies.Here we propose a novel antibacterial nanoplatform of silver nanoparticles-decorat...The mounting threat of antibiotic-resistant bacterial infections has made it imperative to develop innovative antibacterial strategies.Here we propose a novel antibacterial nanoplatform of silver nanoparticles-decorated and mesoporous silica coated single-walled carbon nanotubes constructed via a N-[3-(trimethoxysiltyl)propyl]ethylene diamine(TSD)-mediated method(SWCNTs@mSiO2-TSD@Ag).In this system,the outer mesoporous silica shells are able to improve the dispersibility of SWCNTs,which will increase their contact area with bacteria cell walls.Meanwhile,the large number of mesopores in silica layers act as microreactors for in situ synthesis of Ag NPs with controlled small size and uniform distribution,which induces an enhanced antibacterial activity.Compared with TSD modified mesoporous silica coated single-walled carbon nanotubes(SWCNTs@mSiO2-TSD)and commercialAg NPs,this combination nanosystem of SWCNTs@mSiO2-TSD@Ag exhibits much stronger antibacterial performance against multi-drug-resistant bacteria Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)in vitro through damaging the bacterial cell membranes and a fast release of silver ions.Furthermore,the in vivo rat skin infection model verifies that SWCNTS@mSiO2-TSD@Ag have remarkably improved abilities of bacterial clearance,wound healing promoting as well as outstanding biocompatibility.Therefore,this novel nanoplatform indicates promising potentials as a safe and powerful tool for the treatment of clinical drug-resistant infections.展开更多
The abuse of antibiotics in treating microbial infections has led to the emergence and prevalence of drugresistant bacteria.Thus,the development of novel antibacterial materials is attracting increasing attention.Here...The abuse of antibiotics in treating microbial infections has led to the emergence and prevalence of drugresistant bacteria.Thus,the development of novel antibacterial materials is attracting increasing attention.Here,a series of flexible electrostatic hydrogels with excellent antibacterial ability were constructed using a mixture of nitric oxide(NO)-releasing nitrated chitosan(CSNO)and mesotetra(4-carboxyphenyl)porphine(TCPP)with salmon sperm DNA(ssDNA)solution.When cultured with gram-negative bacteria under solar simulator irradiation,TCPP-CSNO_(m)ssDNA_(n) hydrogels released reactive oxygen species(ROS)and NO to produce peroxynitrite ions(ONOO^(−)).ONOO−is efficient at killing bacteria,thereby improving the antimicrobial ability of photodynamic therapy against gram-negative bacteria.The hydrogels exhibited powerful antibacterial activity in vivo when used to treat skin infections caused by drugresistant bacteria,making them a promising candidate for clinical applications.A string of antibacterial hydrogels that release ROS and NO synergistically can bring new possibilities for effectively killing drug-resistant bacteria and be of great value in anti-infection wound dressings and other applications.展开更多
This study reports the fabrication of a novel photothermal material formed via the physical blending of excess lauric acid(LA)and cupric acetate,followed by efficient ligand exchange.Surprisingly,the copper–LA comple...This study reports the fabrication of a novel photothermal material formed via the physical blending of excess lauric acid(LA)and cupric acetate,followed by efficient ligand exchange.Surprisingly,the copper–LA complex exhibited a 12-fold enhancement of the molar extinction coefficient in the nearinfrared(NIR)region relative to aqueous cupric acetate.Inspired by this interesting finding,we formulated these photothermal materials into colloidally dispersed nanoparticles via a technique that combined nanoprecipitation and in situ surface polymerization for antibacterial studies.The resultant nanoparticles exhibited rapid and stable photothermal responses to NIR irradiation,with a 4-fold enhanced photothermal conversion efficiency relative to aqueous cupric acetate.Since a positively charged monomer was incorporated during in situ surface polymerization,these positively charged nanoparticles were ingested efficiently and subsequently digested by drug-resistant bacteria.By combining the LA-mediated membrane-damaging effect,copper-mediated Fenton-like reaction,as well as the photothermal effect of the copper–LA complex,a broad-spectrum,multimodal,and synergistic antibacterial effect was achieved both in vitro and in vivo,with the killing efficiency up to 99.99%for ampicillin-resistant Escherichia coli(Ampr E.coli)and 99.9999%for methicillinresistant Staphylococcus aureus(MRSA).Our newly developed nanobiocide represents a class of exceptional broad-spectrum antibacterial materials,holding great potential for treating drug-resistant infections in clinical settings.展开更多
通过采用构建16S r DNA克隆文库的非培养方法,对超级杂交水稻品种"深两优5814"及"Y两优900"种子内生细菌群落结构多样性进行研究。实验表明,"深两优5814"种子内生细菌含13个OUT,第一优势菌属为Pantoea,...通过采用构建16S r DNA克隆文库的非培养方法,对超级杂交水稻品种"深两优5814"及"Y两优900"种子内生细菌群落结构多样性进行研究。实验表明,"深两优5814"种子内生细菌含13个OUT,第一优势菌属为Pantoea,丰度为89.44%,第二优势菌和第三优势菌分别为Flavobacterium及Methylobacterium;"Y两优900"种子内生细菌含13个OUT,第一优势菌属为Pantoea,丰度为76.11%,第二优势菌和第三优势菌分别为Pseudomonas及Xanthomonas。由研究可见,泛菌属细菌为水稻种子中的优势菌群,同时,水稻种子基因型对其内生细菌的丰度及多样性具有一定的影响。展开更多
文摘AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm<sup>3</sup>. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.
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.
文摘Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective cohort of patients colonized and/or infected with Gram negative bacteria was conducted at two adult ICUs from hospitals in Brazil (April 2012 to February 2013). Nasal, groin and perineum swabs were performed. Samples were incubated on MacConkey and cetrimide agar (48 h at 37℃) and identification tests (Vitek-BioMérieux), antibiogram (Bauer-Kirby method), Carba NP test, Polymerase Chain Reaction (PCR) and sequencing were performed. The patterns of resistant microorganisms were compared by rep-PCR (Diversilab). Results: There were 53 cases of colonization. In these cases, we identified imipenem-resistant Acinetobacter baumannii (51%), Pseudomonas aeruginosa (32%), Klebsiella pneumoniae ESBL (38%) or imipenem resistant (5.6%). The use of antimicrobials and medical devices were related to colonization (p The resistance patterns expressed by Klebsiella pneumoniae were ESBL (CTX-M, SHV e TEM) and KPC2. A verified profile of Acinetobacter baumannii was related to OXA-23 and OXA-253 (OXA-143 variant). The profiles ESBL and KPC2 expressed by Klebsiella pneumoniae were distributed between the both ICUs. The distribution of OXA-23 and OXA-253 was verified only in one ICU. The similarity of strains ranged from 80% to 95%, highlighting the horizontal transference of these microorganisms.
基金This work is supported by the National Natural Science Foundation of China(Nos.51802192,81802156,and 81772338)the Interdisciplinary Program of Shanghai Jiao Tong University(No.YG2017ZD05)+2 种基金Natural Science Foundation of Shanghai(No.19ZR1474800)Shanghai Sailing Program(No.18YF1410700)Innovation Research Plan supported by Shanghai Municipal Education Commission(No.ZXWF082101).
文摘The mounting threat of antibiotic-resistant bacterial infections has made it imperative to develop innovative antibacterial strategies.Here we propose a novel antibacterial nanoplatform of silver nanoparticles-decorated and mesoporous silica coated single-walled carbon nanotubes constructed via a N-[3-(trimethoxysiltyl)propyl]ethylene diamine(TSD)-mediated method(SWCNTs@mSiO2-TSD@Ag).In this system,the outer mesoporous silica shells are able to improve the dispersibility of SWCNTs,which will increase their contact area with bacteria cell walls.Meanwhile,the large number of mesopores in silica layers act as microreactors for in situ synthesis of Ag NPs with controlled small size and uniform distribution,which induces an enhanced antibacterial activity.Compared with TSD modified mesoporous silica coated single-walled carbon nanotubes(SWCNTs@mSiO2-TSD)and commercialAg NPs,this combination nanosystem of SWCNTs@mSiO2-TSD@Ag exhibits much stronger antibacterial performance against multi-drug-resistant bacteria Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)in vitro through damaging the bacterial cell membranes and a fast release of silver ions.Furthermore,the in vivo rat skin infection model verifies that SWCNTS@mSiO2-TSD@Ag have remarkably improved abilities of bacterial clearance,wound healing promoting as well as outstanding biocompatibility.Therefore,this novel nanoplatform indicates promising potentials as a safe and powerful tool for the treatment of clinical drug-resistant infections.
基金supported by the National Key R&D Program of China(2021YFB3800900)the National Natural Science Foundation of China(22122501,21875014 and 52073013)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910010024)。
文摘The abuse of antibiotics in treating microbial infections has led to the emergence and prevalence of drugresistant bacteria.Thus,the development of novel antibacterial materials is attracting increasing attention.Here,a series of flexible electrostatic hydrogels with excellent antibacterial ability were constructed using a mixture of nitric oxide(NO)-releasing nitrated chitosan(CSNO)and mesotetra(4-carboxyphenyl)porphine(TCPP)with salmon sperm DNA(ssDNA)solution.When cultured with gram-negative bacteria under solar simulator irradiation,TCPP-CSNO_(m)ssDNA_(n) hydrogels released reactive oxygen species(ROS)and NO to produce peroxynitrite ions(ONOO^(−)).ONOO−is efficient at killing bacteria,thereby improving the antimicrobial ability of photodynamic therapy against gram-negative bacteria.The hydrogels exhibited powerful antibacterial activity in vivo when used to treat skin infections caused by drugresistant bacteria,making them a promising candidate for clinical applications.A string of antibacterial hydrogels that release ROS and NO synergistically can bring new possibilities for effectively killing drug-resistant bacteria and be of great value in anti-infection wound dressings and other applications.
基金supported by the start-up funding from Nankai University(to C.Z.)the National Natural Science Foundation of China(nos.52003123,21620102005,and 81722026)the CAMS Innovation Fund for Medical Sciences(no.2016-I2M-3-022).
文摘This study reports the fabrication of a novel photothermal material formed via the physical blending of excess lauric acid(LA)and cupric acetate,followed by efficient ligand exchange.Surprisingly,the copper–LA complex exhibited a 12-fold enhancement of the molar extinction coefficient in the nearinfrared(NIR)region relative to aqueous cupric acetate.Inspired by this interesting finding,we formulated these photothermal materials into colloidally dispersed nanoparticles via a technique that combined nanoprecipitation and in situ surface polymerization for antibacterial studies.The resultant nanoparticles exhibited rapid and stable photothermal responses to NIR irradiation,with a 4-fold enhanced photothermal conversion efficiency relative to aqueous cupric acetate.Since a positively charged monomer was incorporated during in situ surface polymerization,these positively charged nanoparticles were ingested efficiently and subsequently digested by drug-resistant bacteria.By combining the LA-mediated membrane-damaging effect,copper-mediated Fenton-like reaction,as well as the photothermal effect of the copper–LA complex,a broad-spectrum,multimodal,and synergistic antibacterial effect was achieved both in vitro and in vivo,with the killing efficiency up to 99.99%for ampicillin-resistant Escherichia coli(Ampr E.coli)and 99.9999%for methicillinresistant Staphylococcus aureus(MRSA).Our newly developed nanobiocide represents a class of exceptional broad-spectrum antibacterial materials,holding great potential for treating drug-resistant infections in clinical settings.
文摘通过采用构建16S r DNA克隆文库的非培养方法,对超级杂交水稻品种"深两优5814"及"Y两优900"种子内生细菌群落结构多样性进行研究。实验表明,"深两优5814"种子内生细菌含13个OUT,第一优势菌属为Pantoea,丰度为89.44%,第二优势菌和第三优势菌分别为Flavobacterium及Methylobacterium;"Y两优900"种子内生细菌含13个OUT,第一优势菌属为Pantoea,丰度为76.11%,第二优势菌和第三优势菌分别为Pseudomonas及Xanthomonas。由研究可见,泛菌属细菌为水稻种子中的优势菌群,同时,水稻种子基因型对其内生细菌的丰度及多样性具有一定的影响。
