Syntheses and Antibacterial Activity of N-Acylated Ciprofloxacin Derivatives Based on the Trimethyl Lock

相似文献   

Novel Oxazolidinone Antibacterial Analogues with a Substituted Ligustrazine C‐ring Unit

A series of novel oxazolidinone compounds with a substituted ligustrazine C‐ring unit and different substituted groups at the C‐5 side chain were designed and synthesized using linezolid as a lead and based on a scaffold hopping strategy. Their antibacterial and anti‐inflammatory activities were evaluated. The results of in vitro antibacterial assays showed that all fourteen target compounds displayed potent activity against Gram‐positive pathogens, particularly 8b , 13b , 14a , 14b , 15a, and 15b . Moreover, 14a and 14b exhibited significant inhibitory activities on the production of inflammatory mediators, including nitric oxide, interleukin‐6, and tumor necrosis factor‐alpha. Thus, these derivatives could serve as valuable candidates to develop anti‐infective agents for the treatment of chronic wounds.     

Filtration Materials Modified with 2D Nanocomposites—A New Perspective for Point-of-Use Water Treatment

Point-of-use (POU) water treatment systems and devices play an essential role in limited access to sanitary safe water resources. The filtering materials applied in POU systems must effectively eliminate contaminants, be readily produced and stable, and avoid secondary contamination of the treated water. We report an innovative, 2D Ti₃C₂/Al₂O₃/Ag/Cu nanocomposite-modified filtration material with the application potential for POU water treatment. The material is characterized by improved filtration velocity relative to an unmodified reference material, effective elimination of microorganisms, and self-disinfecting potential, which afforded the collection of 99.6% of bacteria in the filter. The effect was obtained with nanocomposite levels as low as 1%. Surface oxidation of the modified material increased its antimicrobial efficiency. No secondary release of the nanocomposites into the filtrate was observed and confirmed the stability of the material and its suitability for practical application in water treatment.     

Effect of UV Irradiation and TiO2-Photocatalysis on Airborne Bacteria and Viruses: An Overview

Current COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has put a spotlight on the spread of infectious diseases brought on by pathogenic airborne bacteria and viruses. In parallel with a relentless search for therapeutics and vaccines, considerable effort is being expended to develop ever more powerful technologies to restricting the spread of airborne microorganisms in indoor spaces through the minimization of health- and environment-related risks. In this context, UV-based and photocatalytic oxidation (PCO)-based technologies (i.e., the combined action of ultraviolet (UV) light and photocatalytic materials such as titanium dioxide (TiO₂)) represent the most widely utilized approaches at present because they are cost-effective and ecofriendly. The virucidal and bactericidal effect relies on the synergy between the inherent ability of UV light to directly inactivate viral particles and bacteria through nucleic acid and protein damages, and the production of oxidative radicals generated through the irradiation of the TiO₂ surface. In this literature survey, we draw attention to the most effective UV radiations and TiO₂-based PCO technologies available and their underlying mechanisms of action on both bacteria and viral particles. Since the fine tuning of different parameters, namely the UV wavelength, the photocatalyst composition, and the UV dose (viz, the product of UV light intensity and the irradiation time), is required for the inactivation of microorganisms, we wrap up this review coming up with the most effective combination of them. Now more than ever, UV- and TiO₂-based disinfection technologies may represent a valuable tool to mitigate the spread of airborne pathogens.     

中华按蚊抗菌肽defensinA编码基因cDNA克隆与序列分析

目的克隆中华按蚊defensin编码基因，并对其序列进行分析。方法提取中华按蚊总RNA。据文献报道合成1对引物deft、def2，RTPCR扩增中华按蚊defensin编码基因，克隆于T-载体，序列测定与分析。结果RT—PCR扩增中华按蚊cDNA获大约308bp片段，测定目的片段序列，结果显示，克隆基因cDNA序列长度为308bp，推导编码64个氨基酸，序列分析显示中华按蚊defensin编码基因与冈比亚按蚊defensin编码基因有高度同源性（95％）。分析结果显示，中华按蚊defensin编码基因为新基因，定名为中华按蚊defensinA。结论克隆出中华按蚊defensinA编码基因，为进一步研究该基因打下了基础。     

Special Considerations for Prophylaxis for and Treatment of Anthrax in Pregnant and Postpartum Women

In August 2012, the Centers for Disease Control and Prevention, in partnership with the Association of Maternal and Child Health Programs, convened a meeting of national subject matter experts to review key clinical elements of anthrax prevention and treatment for pregnant, postpartum, and lactating (P/PP/L) women. National experts in infectious disease, obstetrics, maternal fetal medicine, neonatology, pediatrics, and pharmacy attended the meeting, as did representatives from professional organizations and national, federal, state, and local agencies. The meeting addressed general principles of prevention and treatment for P/PP/L women, vaccines, antimicrobial prophylaxis and treatment, clinical considerations and critical care issues, antitoxin, delivery concerns, infection control measures, and communication. The purpose of this meeting summary is to provide updated clinical information to health care providers and public health professionals caring for P/PP/L women in the setting of a bioterrorist event involving anthrax.     

不同来源金银花类药材抗菌活性研究

目的：对不同来源的金银花类药材的抗菌活性进行研究,比较金银花和山银花的活性,根据研究结果为临床用药和原料生产提供实验依据。方法：测定不同来源对不同菌种MIC50。结果：抗菌活性：山银花〉金银花。     

加替沙星和司帕沙星的光动力抗菌研究

目的 喹诺酮作为抗菌药物在临床上具有一定的光敏毒副作用,那么喹诺酮化合物是否可以作为光敏抗菌药物应用呢？ 基于上述目的我们研究了加替沙星 (GFLX)、司帕沙星 (SPFX) 的光动力抗菌活性。方法 本文报道了 GFLX、SPFX 在 650、450 和 365nm 及白光不同光照波长及激光能量密度与暗反应条件下对耐药菌株金黄色葡萄球菌 (MRSA)、铜绿假单胞菌 (P. aeruginosa)、大 肠埃希菌 (E. coli) 的抗菌活性。结果 GFLX、SPFX 对 MRSA、P. aeruginosa、E. coli 暗毒性最低抑菌浓度 (MIC) ≤ 2.5μg/mL; 最低杀菌浓度 (MBC) ≤ 20μg/mL。GFLX 在 450nm 光照条件下对 MRSA、P. aeruginosa、E. coli 的 MIC 分别为 0.15、0.31 和 0.07μg/ mL;MBC 分别为 0.62、1.25 和 0.15μg/mL。相应的 SPFX 在 650nm 光照条件下抗菌活性分别为 0.31、0.31 和 0.07μg/mL;MBC 分 别为 20、5 和 0.15μg/mL。进一步研究表明 GFLX、SPFX 光动力灭菌活性及细胞毒性具有光波长及能量依赖性。结论 光照可以 一定程度上增加 GFLX 和 SPFX 的抗菌活性,但提升能力有限,在此区间其光敏毒副作用有限,这类药物不会伤及细胞,因而喹 诺酮类药物在临床上不足以作为光敏抗菌药物使用,相对安全。     

穿心莲内酯对铜绿假单胞菌PAO1诱发小鼠感染模型的体内保护作用研究

目的:考察穿心莲内酯对铜绿假单胞菌PAO1诱发小鼠感染模型的体内保护作用。方法:将左氧氟沙星配比不同剂量穿心莲内酯灌胃给予腹腔注射PAO1菌液复制的小鼠细菌感染模型,以小鼠24、48、72 h死亡率为指标,考察穿心莲内酯对左氧氧氟沙星的协同体内抗感染作用;采用全波长多功能酶标仪在420 nm下测定6个不同浓度(100、10、1、0.1、0.01、0.001μg.m L-1)穿心莲内酯对PAO1 24 h内生长速率的影响。结果:穿心莲内酯可有效提高左氧氟沙星对PAO1细菌感染小鼠模型的存活率(P0.05~0.01),但对体外铜绿假单胞菌PAO1生长无影响。结论:穿心莲内酯可提高左氧氟沙星体内抗PAO1的作用,但该作用与其直接抗菌作用无关。     

含镁多孔支架材料的体外抗菌活性和生物相容性

文题释义：快速成型：是一种材料加工方法,它是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术及新材料技术的基础上集成发展起来的。不同种类的快速成型系统因所用成形材料不同,成形原理和系统特点也各有不同,但基本原理都是“分层制造,逐层叠加”。 聚乳酸：是以乳酸为主要原料聚合得到的聚合物,具有良好的生物降解性、生物相容性以及延展性,但其机械强度不足,且降解后会产生酸性代谢产物,限制了其应用范围,常与其他一种或多种生物材料复合使用,以增强骨生物活性或生物力学强度。 背景：将多聚物材料与生物陶瓷材料复合制成有机/无机复合三维支架材料,可赋予支架骨传导所必需的理化特性,同时强化材料的力学性能,但大多数骨替代材料无法预防缺损部位的感染。研究发现由于镁的降解可产生局部碱性环境,使镁具有一定的抗菌活性。 目的：探讨含镁多孔支架材料的体外抗菌活性和细胞相容性。 方法：应用低温快速成型技术制备聚乳酸/β-磷酸三钙/镁多孔支架材料,其中β-磷酸三钙与镁的质量比分别为2∶1和1∶2,分别设为PTM(2∶1)组、PTM(1∶2)组;同时应用低温快速成型技术制备聚乳酸与聚乳酸/β-磷酸三钙多孔支架材料,分别设为P组、PT组。检测4组支架的表面形貌、孔径、孔隙率及压缩模量。将金黄色葡萄球菌(ATCC 35923)接种于4组支架表面24 h,通过涂板计数法和激光共聚焦显微镜观察材料的抗菌活性。将小鼠前成骨细胞MC3T3-E1分别与4组支架材料共培养,通过CCK-8法分析材料对细胞黏附和增殖的影响。 结果与结论：①4组支架材料表面都形成相对均匀的多孔结构,4组支架间孔径大小和孔隙率比较差异均无显著性意义(P > 0.05);②PTM(2∶1)组和PTM(1∶2)组压缩模量明显高于P组、PT组(P < 0.05),PTM(1∶2)组明显高于PTM(2∶1)组(P < 0.05);③涂板计数实验显示,PTM(2∶1)组、PTM(1∶2)组菌落形成单位明显低于P组、PT组(P < 0.05),其余组间比较差异无显著性意义(P > 0.05);④培养6 h,PT组、PTM(2∶1)组、PTM(1∶2)组黏附细胞数量多于P组(P < 0.05),PTM(2∶1)组和PTM(1∶2)组比较差异均无显著性意义(P > 0.05);⑤培养1 d时,仅PT组细胞增殖优于P组(P < 0.05);培养4,7 d时,PT组、PTM(2∶1)组、PTM(1∶2)组细胞增殖均优于P组(P < 0.05),PTM(2∶1)组和PTM(1∶2)组比较差异均无显著性意义(P > 0.05);⑥结果表明,聚乳酸/β-磷酸三钙/镁多孔支架材料不但具有良好的抗菌活性,而且具有优良的细胞相容性和一定的抗压能力。 ORCID: 0000-0002-3367-674X(马瑞) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程