Extensively drug-resistant bacteria are an independent predictive factor of mortality in 130 patients with spontaneous bacterial peritonitis or spontaneous bacteremia

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/mm3. 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.

Excipient effect on antimicrobial activity of Cinnamon (Cinnamomum zelylanicum album) oil, Thyme (Thymus vulgaris) oil and Ajowan (Trachyspermum ammi) oil

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.

Synthesis of Novel Chitosan Microspheres Grafted with β-Cyclodextrins and Their Adsorption for Iodine for Antibacterial Activities

The novel chitosan microspheres grafted with beta-cyclodextrins (CMGC) wereprepared by means of the reaction of chitosan microspheres and mono-(6-p-tosyl)- beta-cyclodextrins(beta-CD-OTs-6). beta-CD-OTs-6 were gained by the reaction of p-toluenesul-fonyl chloride (TsCl) andbeta-cyclodextrins (beta-CDs). Their structures were proved by Fourier transform infrared spectralanalysis (FT-IR), X ray powder diffraction analysis, and ^(13)C NMR; the configuration of CMGC wascharacterized by scanning electron micrograph (SEM) and transmittance electron micrograph (TEM). Theinclusion complex of CMGC with iodine was prepared and its inclusion ability was studied. Theexperimental results showed that some iodine was included with CMGC and formed a stable inclusion.The stable complex of CMGC and iodine (CMGC-1) shows good antibacterial effect.

Biodiversity and Screening of Moderately Halophilic Bacteria with Hydrolytic and Antimicrobial Activities from Yuncheng Salt Lake,China

1 Introduction Yuncheng Salt Lake is an old lake with a history of more than 5000 years,which locates in the margins of the central plains of China,with an area of about 130 km.It was an important resource of salt for human consumption from early times.Major chemicals in Yuncheng Salt Lake contain Na Cl,Na2SO4 and Mg SO4(Gao et al.2007).In recent years,some halophilic bacteria and archaea were

Observation of Traditional Chinese Medicine's Anti-bacterial Effect on the Main Pathogenic Bacteria of Dairy Cow Recessive Mastitis

[Objective]This paper aimed to study the anti-bacterial effect of traditional Chinese medicine on cow recessive mastitis＇ s main pathogenic bacteria and provide basis for its clinical application.[Method]Plating and test-tube methods were used to determine the anti-bacterial diameter,minimum inhibitory concentration（MIC）and minimum bactericidal concentration（MBC）of 20 kinds of traditional Chinese medicine on dairy cow recessive mastitis＇ s clinically isolated main pathogenic bacteria,Staphylococcus aureus and Streptococcus agalactiae.[Conclusion]The results indicated that 7 kinds of traditional Chinese medicine,Herba Taraxaci,Rhizoma Coptidis,Fructus Forsythiae,Herba Andrographis,Radix Scutellar iae,Flos Carthami,Flos Chrysanthemi Indici had strong anti-bacterial effect.

耐药菌的环境分布、传播及新型抗菌技术研究进展

抗生素的广泛使用导致细菌耐药性增加、多重耐药菌菌群数量急剧增多,严重威胁着人类生命健康.环境中耐药菌(ARB)及耐药基因(ARGs)的存在给临床治疗耐药菌感染带来了巨大挑战.有关医院中常见耐药致病菌的研究已有很多,尚缺乏环境中耐药菌的分布、传播及新型耐药菌抗菌技术等的相关研究.本文综述了耐药菌的环境分布特征及其传播机制,概述了新型抗菌技术及其应用,最后展望了有关环境耐药菌研究的未来发展方向.

Medical titanium surface-modified coatings with antibacterial and anti-adhesive properties for the prevention of implant-associated infections

Implant-associated infections(IAIs)caused by drug-resistant bacteria remain a critical factor in the fail-ure of implant procedures.Therefore,it is urgent to develop an effective anti-infection coating for im-plant surface modification to prevent IAIs.Herein,an antibacterial and anti-adhesive coating(CMP-Ti)constructed on the surface of titanium implants is reported,formed by the nanomaterial CeO_(2)@Mn_(3)O_(4) NRs(CM NRs)with antibacterial activity and the superhydrophilic polymer polyethylene glycol(PEG).The nanocatalyst CM NRs on the surface of CMP-Ti induce ferroptosis-like death of bacteria by catalyzing the production of hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2))and the consumption of glutathione(GSH).The superhydrophilic coating of CMP-Ti can effectively prevent adherence of drug-resistant bac-teria and avoid biofilm formation.By combining the"active offense"antibacterial mechanism with the"passive defense"anti-adhesion mechanism,CMP-Ti can kill bacteria and inhibit biofilm formation.The results of in vivo studies showed that CMP-Ti effectively prevented implant-associated infections caused by Methicillin-resistant Staphylococcus aureus(MRSA),thus promoting tissue repair and osseointegra-tion.Therefore,this multifunctional coating combining"active offense"and"passive defense"provides a promising way to prevent IAIs caused by drug-resistant bacteria and to promote tissue repair in the future.

天然植物多糖的提取、分离及其在皮肤领域的研究进展

植物多糖是一种从植物各部位中提取的天然高分子聚合物,由十个或十个以上的单糖单元通过糖苷键聚合而成。近年来,由于其丰富的生物活性、安全性、亲肤性等特点越来越受到人们的关注。多糖的结构和功能之间具有密切关系,不同的提取和纯化方法会对多糖的结构产生影响,进而改变其生物活性。本文阐述了植物多糖的提取、分离、纯化工艺,并同时对植物多糖具有的保湿补水、抗氧化、抗炎、抑菌、美白等功效进行了总结,以期为植物多糖在功能化妆品的开发和应用提供理论支撑。

乳酸菌发酵对花生衣抗糖化缓解皮肤衰老功能的影响

糖化会导致晚期糖基化终末产物(AGEs)形成并在体内积累,引起皮肤衰老。体外实验表明花生衣具有抗糖化作用,乳酸菌发酵能否提升花生衣的抗糖能力尚不清楚。本研究采用体外AGEs生成模型和丙酮醛损伤皮肤成纤维细胞(HSF)模型,从10株乳酸菌中筛出植物乳植杆菌CCFM1354,该菌具有很好的抑制AGEs生成能力,能缓解HSF细胞的糖化损伤。高糖细胞模型实验发现,CCFM1354发酵花生衣能显著降低HSF细胞中BAX和NFKB1的mRNA的相对表达量;D-半乳糖诱导的衰老小鼠实验结果表明,口服植物乳植杆菌CCFM1354发酵花生衣能显著降低小鼠血清AGEs含量,提高小鼠皮肤弹性,改善小鼠皮肤萎缩状况,且效果优于未发酵花生衣。由此可见,植物乳植杆菌CCFM1354发酵能显著提升花生衣的抗糖化功能,缓解皮肤衰老。

防根面龋牙科材料的研究进展

根面龋是老年人口腔常见病和多发病,发病率和未治疗率高,治疗难度大,可迅速进展引起牙髓根尖周病或残冠根,是老年人失牙的重要原因,已成为严重影响老年人生活质量的常见口腔慢性病之一。因此,根面龋早期干预和防治非常重要。传统防根面龋牙科材料如氟化物、氯己定等在临床中广泛应用,但是其具有牙齿着色、再矿化及杀菌效率低下等缺点。近年来,一系列新兴防根面龋牙科材料如无机纳米材料、胶原交联剂等逐步成为研究热点,新兴材料具有促进深部牙体组织再矿化、作用时间延长、黏附力增强等优点。未来防龋材料应根据根面龋的特点及应用人群进行设计,朝着简便化、高效化、低毒性方面发展。本文对目前防根面龋牙科材料的研究及应用进行综述,以期能够为防根面龋牙科材料的研究提供理论基础,对促进根面龋的有效预防,改善老年人的口腔健康状况和生活质量具有重要意义。

二氧化氯的抗菌效果及其在食品保鲜中的研究进展

二氧化氯是一种强氧化剂,其对微生物细胞膜、蛋白、遗传物质的破坏作用以及对果蔬中乙烯的代谢抑制和氧化作用,使其具有优良的杀菌、食品保鲜效果,是稳定可靠的食品保鲜剂。主要对二氧化氯的生物安全性、抗菌保鲜机理、抗菌效果以及其在食品保鲜中的研究和应用进展进行综述,并对未来的研究重点提出建议。

基于RBL-2H3细胞脱颗粒抑制作用的体外抗过敏活性益生菌的筛选及鉴定

为探究乳酸菌的抗过敏活性,本研究采用传统分离技术从发酵蔬菜中获得乳酸菌,并进行益生菌体外评价,结合RBL-2H3细胞脱颗粒抑制实验筛选具有抗过敏活性的益生菌。结果表明,从发酵蔬菜中分离的4株菌株表现出良好的益生特性和安全性;所选4株乳酸菌对RBL-2H3细胞脱颗粒释放β-己糖胺酶均具有较高的抑制作用,并对RBL-2H3细胞脱颗粒释放组胺、肿瘤坏死因子-α和白介素-4均有明显的下调作用,具有作为抗过敏活性益生菌的可能性。4株菌株经16S rDNA测序鉴定为植物乳杆菌2株、发酵乳杆菌和副干酪乳杆菌各1株。

硫酸黏菌素联合治疗ICU内广泛耐药革兰阴性杆菌感染的疗效与安全性

目的:评价硫酸黏菌素治疗ICU内广泛耐药(XDR)革兰阴性杆菌感染的疗效与安全性。方法:纳入我院ICU收治的XDR革兰阴性杆菌感染并使用硫酸黏菌素治疗的患者,收集其目标病原菌、联合用药方案、给药方式及剂量等,观察和评估其疗效与不良反应。结果:使用硫酸黏菌素联合抗感染治疗的患者共109例,临床有效68例(62.4%);细菌学清除65例(59.6%);发生肾损伤不良反应3例(2.8%),其中1例为很可能,2例为可能。结论:对于XDR革兰阴性杆菌感染的重症患者,以硫酸黏菌素为基础的联合抗感染方案具有较好的疗效,雾化吸入安全性较高,但仍需关注其肾损伤可能的不良反应。

冰川前缘冰舌区可培养细菌多样性及抗辐射-抗氧化特征——以老虎沟12号冰川为例

全球变化导致气温上升加速冰川退缩,冰川前缘进化出大量抗辐射-抗氧化微生物资源。细菌作为影响冰川前缘演替过程的重要类群之一,对其冰舌区新融化的冰碛物生境中抗辐射-抗氧化细菌的研究却较为少见。基于16S rRNA基因序列系统发育学的研究,不仅对老虎沟12号冰川前缘冰舌区冰碛物生境可培养细菌多样性进行研究,同时对菌株的抗辐射和抗氧化能力进行筛选和评估。研究表明,研究区域分离出的259株细菌分别归属于放线菌门(Actinobacteria)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和异常球菌-栖热菌门(Deinococcus-Thermus),其中放线菌门的菌株数量最多,其次是变形菌门>拟杆菌门>厚壁菌门>异常球菌-栖热菌门;在物种多样性方面,放线菌门和变形菌门是物种丰富度最高的门。TN、TOC、WC和pH是影响可培养细菌群落结构的主要因素。UVC辐照强度的D10(致死率为10%)剂量高于100 J·m^(-2)的菌株占可培养细菌总数的94.9%,过氧化氢耐受浓度的D10剂量高于10 mmol·L^(-1)的菌株占100%;其中有20株抗辐射菌株氧化胁迫后的存活率在90%以上。此外,氧化胁迫后存活率高于Deinococcus-radiodurans R1的菌株均是100 J·m^(-2)UVC辐照后抗辐射存活率高于50%的抗辐射菌株。该研究不仅可以为冰川前缘环境中细菌的多样性和生态适应性提供理论基础,也可以为后续辐照、氧化损伤保护机制的研究提供丰富的抗辐射-抗氧化冰川细菌资源。

土曲霉抗耐药菌活性成分及其逆转耐药性作用研究

目的探讨土曲霉的抗菌活性成分及其对临床耐药菌的逆转作用。方法采用体外抗菌活性导向法及现代分离技术对土曲霉的代谢产物进行活性物质分离,采用核磁共振波谱法和质谱法确定化合物的结构。采用96孔板测定单体化合物对耐药菌的作用,筛选活性成分,并在无抗菌作用的浓度下分析活性成分对抗菌药物、耐药菌株最低抑菌浓度(MIC)的影响,评价活性成分逆转耐药菌耐药性的作用。结果从土曲霉的活性组分中分离出5种化合物,分别为烟曲霉酸(HA,化合物1)、对羟基苯丙酸(化合物2)、对甲氧基苯甲酸(化合物3)、吲哚-3-乙酸(化合物4)、对羟基苯甲酸(化合物5)。HA对多重耐药菌金黄色葡萄球菌、表皮葡萄球菌、屎肠球菌的抑菌圈大小分别为(21.00±0.37)mm、(19.00±0.21)mm、(32.00±0.23)mm。HA在1/2 MICHA的浓度下,使头孢曲松对耐药菌金黄色葡萄球菌、表皮葡萄球菌、屎肠球菌的MIC分别降低了75.00%,75.00%,87.50%,使氨苄西林对上述3种耐药菌的MIC分别降低了75.00%,75.00%,93.75%,使左氧氟沙星和环丙沙星对上述3种耐药菌的MIC均降低了75.00%;HA在1/4 MICHA的浓度下,使头孢曲松、氨苄西林、左氧氟沙星、环丙沙星对耐药菌金黄色葡萄球菌、表皮葡萄球菌的MIC均降低了50.00%,使头孢曲松、氨苄西林、左氧氟沙星、环丙沙星对耐药菌屎肠球菌的MIC分别降低了50.00%,87.50%,50.00%,50.00%;HA在1/8 MICHA的浓度下,使左氧氟沙星、环丙沙星对耐药菌金黄色葡萄球菌的MIC均降低了50.00%,使头孢曲松对耐药菌表皮葡萄球菌的MIC降低了50.00%,使氨苄西林、左氧氟沙星、环丙沙星对耐药菌屎肠球菌的MIC分别降低75.00%,50.00%,50.00%。结论化合物2至化合物5均为从真菌土曲霉代谢物中首次分离出。HA是土曲霉抗多重耐药菌的主要活性成分,对多重耐药菌金黄色葡萄球菌、表皮葡萄球菌和屎肠球菌均有抗菌、逆转耐药性作用,对3种耐药菌的最佳逆转浓度为1/2 MICHA。

泡菜中产β-葡萄糖苷酶植物乳杆菌的益生和酶学特性

乳酸菌因自身特性和分泌多种代谢物而在发酵过程中起重要的作用。从泡菜中筛选出2株高产β-葡萄糖苷酶乳酸菌,经16S rRNA基因测序比对后均鉴定为植物乳杆菌(命名为PC7-C6和PC7-C11)。随后对2菌株的益生特性以及酶产量较高的PC7-C11的酶学特性进行分析。结果显示:2菌株为γ-溶血,对氨苄西林、克拉霉素敏感,对四环素、红霉素和克林霉素中度敏感;可在pH 4条件下生长;培养8 h后自聚集率在50%~64%范围,与大肠杆菌共聚集率均大于60%;对乙酸乙酯的疏水率分别为70.41%,61.19%,对二甲苯和正己烷的疏水率在30%~40%范围;能够抑制大肠杆菌、蜂房哈夫尼菌、腐生葡萄球菌、粘质沙雷氏菌和马胃葡萄球菌等细菌的生长;PC7-C11的抗氧化能力优于PC7-C6,PC7-C11对DPPH自由基清除率和羟自由基清除率分别为59.33%和53.49%。植物乳杆菌PC7-C11菌株酶活力的最适反应温度40℃、最适pH值7,乙醇、葡萄糖、二甲基亚砜、SDS、EDTA、Fe^(2+)、Mg^(2+)、Na^(+)、Ca^(2+)会不同程度地抑制酶活,K^(+)对酶活力有一定的促进作用。

北部湾海洋真菌Aspergillus fumigatus DL-p0m-g2的化学成分及药理活性研究

为获得具有生物活性的化合物,对一株分离于北部湾钉螺菌株Aspergillus fumigatus DL-p0m-g2的化学成分及药理活性进行研究。综合应用反相ODS(octadecylsilyl)柱色谱、半制备液相等多种色谱学方法进行分离纯化,根据化合物理化性质、质谱和核磁共振波谱学数据进行结构鉴定,并对分离得到的化合物进行细胞毒活性、抑菌活性和胆固醇转运蛋白NPC1L1(NPC1-like intracellular cholesterol transporter 1)蛋白结合等生物活性评价。实验共分离得到21个生物碱类化合物和1个甾体,分别鉴定为6-methoxyspirotryprostatin B(1)、spirotryprostatin A(2)、fumitremorgin C(3)、cyclotryprostatin A(4)、fumitremorgin B(5)、pseurotin A(6)、azaspirofuran A(7)、azaspirofuran B(8)、cephalimysin C(9)、cephalimysin B(10)、fumiquinazoline C(11)、fumiquinazoline B(12)、fumiquinazoline A(13)、fumiquinazoline D(14)、fumiquinazoline F(15)、tryprostatin B(16)、verruculogen(17)、chaetominine(18)、bisdethiobis(methylthio)glitoxin(19)、helvolic acid(20)、7-deacetylpyripyropene A(21)、terezine D(22)。其中化合物6对人肝癌细胞(Hep G2)、人肺癌细胞(A549)、人直肠癌细胞(HCT116)有一定的细胞毒活性;化合物1、3和20对金黄色葡萄球菌表现出抑菌活性;化合物14与NPC1L1蛋白具有较好的结合,显示其在降脂药物开发中的研究潜力。

树木防冻防病膜剂室内抑菌效果研究

【目的】探究树木防冻防病膜剂的抑菌效果,为生产提供一种良好的防冻保护剂。【方法】利用课题组研制的树木防冻防病膜剂对2种冰核细菌(丁香假单胞菌和菠萝泛生氏菌)和3种真菌(小穴壳菌属、金黄壳囊孢菌、污黑腐皮壳菌)进行抑菌效果研究,并与市面常用药剂进行比较。采用滤纸片扩散法对比3个浓度(0.3‰、0.6‰和1‰)下农用链霉素和防冻防病膜剂对两种冰核细菌抑制效果。采用生长速率法对比4个浓度(100 mg·L^(-1)、300 mg·L^(-1)、600 mg·L^(-1)和1000 mg·L^(-1))下多菌灵、甲基硫菌灵、百菌清和防冻防病膜剂4种药剂对3种引起杨树溃疡病和烂皮病真菌的抑制效果。【结果】(1)与农用链霉素相比,防冻防病膜剂对2种冰核细菌的抑制效果较好,且抑菌效果随着药剂浓度的增大而增大。在设置的最高试验浓度下,防冻防病膜剂对丁香假单胞菌和菠萝泛生氏菌的抑菌直径分别为10.9 mm和19.1 mm。(2)多菌灵和甲基硫菌灵对3种真菌抑制效果较好,多菌灵在100 mg·L^(-1)浓度下对3种真菌抑制率能达到100%,甲基硫菌灵在100 mg·L^(-1)浓度下对2种真菌(金黄壳囊孢菌、污黑腐皮壳菌)抑制率能达到100%,在600 mg·L^(-1)浓度下对小穴壳菌属抑制率能达到100%。(3)防冻防病膜剂与百菌清对3种真菌的抑制效果相当,防冻防病膜剂的抑制效果随着药剂浓度增大而增强,当浓度达到1000 mg·L^(-1)时,抑菌率为100%。【结论】树木防冻防病膜剂对2种冰核细菌和3种真菌均有较好抑制效果。

Silver nanoparticles-decorated and mesoporous silica coated single-walled carbon nanotubes with an enhanced antibacterial activity for killing drug-resistant bacteria

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.

Mechanisms, prevention and clinical implications of nonsteroidal anti-inflammatory drug-enteropathy

This article reviews the latest developments in understanding the pathogenesis, detection and treatment of small intestinal damage and bleeding caused by nonsteroidal anti-inflammatory drugs (NSAIDs). With improvements in the detection of NSAID-induced damage in the small intestine, it is now clear that this injury and the associated bleeding occurs more frequently than that occurring in the stomach and duodenum, and can also be regarded as more dangerous. However, there are no proven-effective therapies for NSAID-enteropathy, and detection remains a challenge, particularly because of the poor correlation between tissue injury and symptoms. Moreover, recent studies suggest that commonly used drugs for protecting the upper gastrointestinal tract (i.e., proton pump inhibitors) can significantly worsen NSAID-induced damage in the small intestine. The pathogenesis of NSAID-enteropathy is complex, but studies in animal models are shedding light on the key factors that contribute to ulceration and bleeding, and are providing clues to the development of effective therapies and prevention strategies. Novel NSAIDs that do not cause small intestinal damage in animal models offer hope for a solution to this serious adverse effect of one of the most widely used classes of drugs.