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1.
The WHO has stated that antibiotic resistance is escalating to perilously high levels globally and that traditional therapies of antimicrobial drugs are futile against infections caused by resistant microorganisms. Novel antimicrobial drugs are therefore required. We report in this study on the inhibitory activity of the 1,4-naphthoquinone-2,3-bis-sulfides and 1,4-naphthoquinone sulfides against two bacteria and a fungus to determine their antimicrobial properties. The 1,4-naphthoquinone sulfides have potent activity with a minimum inhibitory concentration (MIC) of 7.8 μg/mL against Staphylococcus aureus (Gram +ve), an MIC of 23.4 μg/mL against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.3 μg/mL), and against Escherichia coli (Gram −ve) an MIC of 31.3 μg/mL was obtained. The 1,4-naphthoquinone had an MIC of 11.7 μg/mL against S. aureus and the 1,4-naphthohydroquinone also had the same activity against E. coli.
Hit, Lead & Candidate Discovery
  相似文献   
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These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of post‐operative surgical site infections (SSIs) in solid organ transplantation. SSIs are a significant cause of morbidity and mortality in SOT recipients. Depending on the organ transplanted, SSIs occur in 3%‐53% of patients, with the highest rates observed in small bowel/multivisceral, liver, and pancreas transplant recipients. These infections are classified by increasing invasiveness as superficial incisional, deep incisional, or organ/space SSIs. The spectrum of organisms implicated in SSIs in SOT recipients is more diverse than the general population due to other important factors such as the underlying end‐stage organ failure, immunosuppression, prolonged hospitalizations, organ transportation/preservation, and previous exposures to antibiotics in donors and recipients that could predispose to infections with multidrug‐resistant organisms. In this guideline, we describe the epidemiology, clinical presentation, differential diagnosis, potential pathogens, and management. We also provide recommendations for the selection, dosing, and duration of peri‐operative antibiotic prophylaxis to minimize post‐operative SSIs.  相似文献   
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This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.

The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same.  相似文献   

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目的:研究复方益气润肠胶囊对肠道常见细菌的体外抗菌作用,及对正常小鼠、便秘小鼠排便和肠推进作用的影响。方法:采用微量稀释法测定复方益气润肠胶囊对多种常见临床致病菌(金黄色葡萄球菌耐甲氧西林株、肺炎克雷伯菌、鼠伤寒沙门菌、蜡样芽孢杆菌、粪肠球菌、藤黄微球菌、铜绿假单胞菌等)的最小抑菌浓度(MIC)值,以评价其体外抗菌活性;通过小鼠肠推进实验观察该胶囊对正常小鼠肠推进率的影响和对便秘模型小鼠首次排黑便时间、6 h排便量及肠推进率的影响。结果:抗菌实验显示,复方益气润肠胶囊体外对金黄色葡萄球菌耐甲氧西林株M1233和肺炎克雷伯菌的MIC均为3.125 mg/mL,对金黄色葡萄球菌耐甲氧西林株M1805、铜绿假单胞菌、蜡样芽孢杆菌、粪肠球菌及藤黄微球菌的MIC均为6.250 mg/mL,对鼠伤寒沙门菌的MIC为25.000 mg/mL。对正常小鼠的肠推进实验显示,复方益气润肠胶囊高、中、低剂量给药组小肠推进率均高于空白组,差异有统计学意义(P<0.05或P<0.01);对便秘模型小鼠的肠推进实验显示,各给药组首次排黑便时间均短于便秘模型组,6 h排便量均大于便秘模型组,小鼠肠推进率均高于便秘模型组,差异有统计学意义(P<0.05或P<0.01)。结论:复方益气润肠胶囊具有理想的体外抗菌效果和较好的肠推进作用。  相似文献   
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目的:药学干预对喹诺酮类抗菌药物临床合理用药的影响效果。方法:选取2017年4月~2018年3月、2018年4月~2019年3月两时段就诊的患者,分别设为对照阶段、观察阶段,在两个阶段内于某院就诊且接受喹诺酮类抗菌药物治疗患者各选取115例,分别作为观察组及对照组,实施或未实施药学干预,分析组间干预效果差异。结果:观察组干预后喹诺酮类抗菌药物引发的不良反应发生率低于对照组(P<0.05);观察组干预后不合理使用率均低于对照组(P<0.05)。结论:药学干预对喹诺酮类抗菌药物临床合理用药能够产生积极影响效果。  相似文献   
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俞小霞  王巧红 《临床荟萃》2021,36(2):153-156
目的 分析我院147例泌尿系感染住院患儿的临床及治疗情况,并结合国内外新的研究进展,为临床诊治提供参考依据。方法 应用描述性方法对我院2016年5月至2020年5月住院的147例泌尿系感染病例进行回顾性分析。结果 147例患儿中,男性88例(59.86%)。婴儿期人数最多,共63例(42.86%)。尿培养中以屎肠球菌及大肠埃希菌多见。治疗上有136例(92.52%)选用头孢菌素类抗生素,其中三代头孢有132例(89.80%);45例行排泄性膀胱输尿管造影的患儿中有22例(48.89%)存在膀胱输尿管返流。结论 泌尿系感染是儿童的常见病,由于它与泌尿系畸形特别是膀胱输尿管返流密切相关,易导致感染反复,因此早期诊治并寻找其潜在的畸形,可预防复发,改善预后。  相似文献   
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Infections caused by Gram-positive and -negative bacteria are one of the foremost causes of morbidity and mortality globally. Antibiotics are the mainstay of therapy for bacterial infections, but the emergence and wide spread of drug-resistant pathogens have already become a huge issue for public healthcare systems. The coumarin moiety, which is ubiquitous in nature, could bind to the B subunit of DNA gyrase in bacteria and inhibit DNA supercoiling by blocking the ATPase activity; hence, coumarin derivatives possess potential antibacterial activity. Several coumarin-containing hybrids such as coumermycin A1, clorobiocin, and novobiocin have already been used in clinical practice for the treatment of various bacterial infections; thus, it is conceivable that hybridization of the coumarin moiety with other antibacterial pharmacophores may provide opportunities for the development of novel antibiotics. This review outlines the advances in coumarin-containing hybrids with antibacterial potential in the recent 5 years and the structure–activity relationships are also discussed.  相似文献   
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