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Advances in Microbiology 2024年第2期14卷 122-136页

作者： Naif M. Alhawiti Agnes K. Nthenge Waeel h. Alramadhan William Boadi Abdulrahman F. Alqahtani Elber-Lewis Myles CAhFS University of California Davis USA Department of Agricultural and Environmental Sciences College of Agriculture Tennessee State University Nashville USA Department of Biological Science Tennessee State University Nashville USA Department of Chemistry Tennessee State University Nashville USA Saudi Food and Drug Authority Riyadh Saudi Arabia

The use of antibiotics in humans and animals has been marked as a significant step in health due to their effectiveness in controlling and treating bacterial infections. The misuse and overuse of antibiotics have been identified as risk factors for bacterial resistance since microorganisms adapt and develop mechanisms to defend against antibiotics. According to the Centers for Disease Protection and Control (CDC), around 23,000 individuals die every year in the United States due to antibiotic resistance complications. As a result, a demand for alternative treatments has been a goal for scientists as the microbes adapt to selective pressure. The aim of this study is to test the antibacterial activity of leaf extracts of Peganum harmala and haloxylon salicornicum on both gram-positive and gram-negative bacteria on various mediums. The results of the study showed that both P. harmala and h. salicornicum inhibited the bacterial growth in two different media. The results were also compared with different common antibiotics used in both human’s and animal’s fields and showed a promising outcome as alternative antibiotics.

关键词： Peganum harmala haloxylon salicornicum Antibiotics Resistance Medicinal Plants gram-Positive gram-Negative

Rauvolfia serpentina-Mediated Green Synthesis of CuO Nanoparticles and Its Multidisciplinary Studies

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1134-1140页

作者： K.Lingaraju h.Raja Naika K.Manjunath G.Nagaraju D.Suresh h.Nagabhushana Department of Studies and Research in Environmental Science Tumkur University Centre for Nano and Material Sciences Jain University Department of Chemsitry Siddaganga Institute of Technology Department of Studies and Research in Chemistry Tumkur University Prof. C.N.R. Rao Center for Advanced Materials Tumkur University

Copper oxide nanoparticles （CuO Nps） were successfully synthesized by solution combustion method using aqueous leaf extract of Rauvolfia serpentina as a fuel. The structure and morphology of the CuO nanoparticles （Nps） were characterized by powder X-ray diffraction （PXRD）, UV-visible spectroscopy （UV-visible）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, etc. The PXRD patterns reveal the formation of monoclinic phase with crystallite structure. SEM images indicate that the particles have sponge-like structure being highly porous and agglom- erated with large surface area. The average crystallite sizes were found to be in the range of 10-20 nm by Scherrer＇s method. The CuO Nps size was further confirmed by TEM. Further, CuO Nps exhibit good photocatalytic activity for the photodegradation of trypan blue dye, indicating that it acts as a promising semiconducting material. The antibacterial properties of CuO nanoparticles were investigated against pathogenic bacterial strains, namely gram -ve Escherichia coli （NCIM-5051） and Pseudomonas desmolyticum （NCIM-2028） and gram ＋ve bacteria Staphylococcus aureus （NCIM- 5022） using the agar well diffusion method.

关键词： CuO Nanoparticles Rauvolfia serpentina Photocatalytic activity Antibacterial activity

Photoredox-catalyzed [4+2] annulation of cyclobutylanilines with alkenes, alkynes, and diynes in continuous flow

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Science China Chemistry 2016年第2期59卷 180-183页

作者： Jiang Wang Theresa h.Nguyen Nan Zheng Department of Chemistry and Biochemistry University of Arkansas

Continuous flow has recently emerged as a powerful enabling technology that greatly improves many reactions' efficiency. here, we apply the technology to intermolecular [4+2] annulation of cyclobutylanilines with alkenes, alkynes, and diynes by photoredox catalysis. An across-the-board improvement in the annulation's efficiency is noticed. Moreover, a gram-scale annulation is successfully demonstrated in continuous flow using a much lower catalyst loading.

关键词： photocatalysis continuous flow N-cyclobutylanfline [4+2] annulation visible light

Labelling of a pyrazole derivative with ^(131)I and investigation of its radiopharmaceutical potential

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Chinese Science Bulletin 2013年第24期58卷 2964-2969页

作者： KURTDEDE Esra BILDIRICI Ishak ENGINAR hüseyin SENER Ahmet Department of Chemistry Faculty of Arts and Sciences Afyon Kocatepe University Department of Chemistry Faculty of Arts and Sciences Yuzuncu Yil University

We investigated the radiolabeling efficiency, in vitro stability, and biodistribution of radioactive iodine (131I)-labeled 4-benzoyl-1-(4-carboxyphenyl)-5-phenyl-1h-pyrazole-3-carboxylic acid (P3CA). A quality-control study of the labeled substance ( 131I-P3CA) was conducted using electrophoresis and radio thin-layer chromatography (RTLC). Biodistribution studies were undertaken in 9 female albino Wistar rats. Rats were killed at various times (15, 60 and 180 min), their organs removed, and percentage of injected dose per gram (ID%/g) values calculated. The labeling yield of P3CA was 97.08%±0.80%. The maximum uptake of 131I-P3CA was seen in the lungs, stomach and spleen at 15 min. The uptake of labeled compound decreased over time in the lungs, whereas that in the stomach decreased. These data suggest that 131I-P3CA had high binding efficiency, high uptake in the lung, and sufficient stability to be used in diagnostic studies.

关键词：吡唑衍生物放射性药物 Wistar大鼠放射性标记体外稳定性标签羧基苯基放射性碘

Use of rifaximin in gastrointestinal and liver diseases

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World Journal of Gastroenterology 2016年第29期22卷 6638-6651页

作者： Rani h Shayto Rachel Abou Mrad Ala I Sharara Division of Gastroenterology Department of Internal Medicine American University of Beirut Medical Center

Rifaximin is a broad spectrum oral antibiotic with antimicrobial activity against gram-positive and gram-negative aerobic and anaerobic bacteria. It is poorly absorbed and thus has a highly favorable safety profile. Rifaximin has been shown to be effective in the treatment of traveler’s diarrhea, functional bloating and irritable bowel syndrome, small bowel bacterial overgrowth and in the prevention of recurrent overt hepatic encephalopathy. In addition, there is emerging evidence for a possible beneficial effect of rifaximin in the treatment of uncomplicated diverticular disease and in the prevention of recurrent diverticulitis. The use of rifaximin is associated with a low incidence of development, or persistence of spontaneous bacterial mutants. Moreover, the development of important drug resistance among extra-intestinal flora during rifaximin therapy is unlikely because of minimal systemic absorption and limited cross-resistance of rifaximin with other antimicrobials. This review addresses the current and emerging role of rifaximin in the treatment of gastrointestinal and liver disorders.

关键词： Irritable bowel syndrome Inflammatory bowel disease hepatic encephalopathy Bacterial overgrowth Diverticular disease

Non-Inductive Start up of QUEST Plasma by RF Powert

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Plasma Science and Technology 2011年第3期13卷 307-311页

作者： K. hANADA h. ZUShI h. IDEI K. NAKAMURA M. IShIGURO S. TAShIMA E. I. KALINNIKOVA M. SAKAMOTO M. hASEGAWA A. FUJISAWA A. hIGAShIJIMA S. KAWASAKI h. NAKAShIMA h. LIU O. MITARAI T. MAEKAWA A. FUKUYAM Y. TAKASE J. QIAN Research Institute for Applied Mechanics Kyushu University Japan Interdisciplinary Graduate School of Engineering Science Kyushu University Japan School of Industrial Engineering Tokai University Japan Graduate School of Energy Science Kyoto University Japan Graduate School of Technology Kyoto University Japan Graduate School of Frontier Science University of Tokyo Japan Institute of Plasma Physics Chinese Academy of Sciences China

Both start-up and sustainment of plasma were successfully achieved by fully non- inductive current drive using microwave with a frequency of 8.2 Ghz. Plasmas current of 15 kA was implemented for 1 s. Magnetic surface reconstruction exhibited a plasma shape with an aspect ratio of below 1.5. The plasma current was dependent significantly on the launched microwave power and vertical magnetic field, while not affected by the mode of launched wave and the toroidal refractive index. hard X-ray （hXR） emitted from energetic electrons accelerated by the microwave was observed, and the discharge with a plasma current over 4 kA followed the same trend as the number of photons of 10 keV to 12 keV. This suggests that the plasma current may be driven by energetic electrons. Based on the experimental conditions, alternative explanations of how the plasma current could be driven are discussed.

关键词： steady-state operation of spherical tokamak non-inductive current drive QUEST

Synthesis, Structural Characterization, and Antimicrobial Activities of Mn（II）, Co（II）, Ni（II）, Cu（ll） and Zn（II） Complexes of Triazole-based Azodyes

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Chinese Journal of Chemistry 2011年第6期29卷 1124-1132页

作者： Khedr, Abdalla M. Gaber, Mohamed Abd EI-Zaher, Eman h. Chemistry Department Faculty of Science Tanta University Tanta Egypt Botany Department Faculty of Science Tanta University Tanta Egypt

The synthesis and characterization of new transition metal complexes of Mn（ll）, Co（II）, Ni（II）, Cu（II） and Zn（II） with 3-（2-hydroxynaph-l-ylazo）-1,2,4-triazole （hL1） and 3-（2-hydroxy-3-carboxynaph-l-ylazo）-1,2,4-triazole （hL2） have been carried out. Their structures were confirmed by elemental analyses, thermal analyses, spectral and magnetic data. The IR and 1h NMR spectra indicated that hL1 and hL2 coordinated to the metal ions as bidentate monobasic ligands via the hydroxyl O and azo N atoms. The UV-Vis, ESR spectra and magnetic moment data revealed the formation of octahedral complexes [MnL1（AcO）（h2O）3] （1）, [CoL1（AcO）（hzO）3]·h2O （2）, [MnL2- （AcO）（h20）3] （6） and [CoL2（AcO）（h2O）3] （7）, [NiL1（AcO）（h2O）] （3）,[ZnLI（AcO）（hzO）]·h2O （5）, [NiL2- （AcO）（h2O）] （8）, [ZnL2（AcO）（h2O）]·h2O （10） have tetrahedral geometry, whereas [CuLI（AcO）（h2O）2] （4） and [CuL2（AcO）（h2O）2]·5h2O （9） have square pyramidal geometry.. The mass spectra of the complexes under EI-con- ditions showed the highest peaks corresponding to their molecular weights, based on the atomic weights of 55Mn, 59Co, 58Ni, 63Cu and 64Zn isotopes; besides, other peaks containing other isotopes distribution of the metal. Kinetic and thermodynamic parameters of the thermal decomposition stages were computed from the thermal data using Coats-Redfern method. hL2 and complexes 6--10 were found to have moderate antimicrobial activities against Staphylococcus＇ aureus （gram positive）, Escherichia coli （gram negative） and Salmonella sp bacteria, and antifungal activity against Fusarium oxysporum, Aspergillus niger and Candida albicans. Also, in most cases, metallation increased the activity compared with the free ligand.

关键词： analytical and inorganic chemistry triazole azodyes metal(II) chelates antimicrobial activities

Metal nanoparticles as inhibitors of enzymes and toxins of multidrug-resistant Staphylococcus aureus

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Infectious Medicine 2023年第4期2卷 294-307页

作者： Amruta A.Joshi Ravindra h.Patil Department of Microbiology and Biotechnology R.C.Patel ArtsCommerce and Science CollegeShirpurMaharashtra 425405India

Staphylococcus aureus is an aerobic gram-positive spherical bacterium known to cause a broad range of infections *** is a major cause of infective skin and soft infections and severe and life-threatening conditions,such as pneumonia,bloodstream infections,and *** emergence of drug-resistant strains of S aureus,par-ticularly methicillin-resistant S aureus(MRSA),has become a significant concern in the healthcare ***-resistant S aureus is commonly acquired in hospitals and long-term care *** often affects pa-tients with weakened immune systems,those undergoing invasive medical procedures,or those who have been hospitalized for extended *** the US,S aureus is known to cause potentially fatal illnesses,such as toxic shock syndrome(TSS)and acute-onset toxic shock syndrome(TSS),which are characterized by fever and *** develops resistance to antibiotics through several mechanisms,such as the production of enzymes that inactivate antibiotics,target site modification,efflux pumps,and plasmid-mediated ***,preventing the spread of drug-resistant S aureus is needed,and there is an urgent need to explore novel ap-proaches in the development of anti-staphylococcal *** article reviews the principal infections caused by S aureus,major virulence factors,mechanisms of resistance development,and nanotechnology-based solutions for the control of drug-resistant S aureus.

关键词： Staphylococcus aureus Drug resistance Efflux pumps Plasmid Nanotechnology Inhibitors

Genomic insights into the ESBL and MCR-l-producing ST648 Escherichia coli with multi-drug resistance

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Science Bulletin 2016年第11期61卷 875-878页

作者： huimin Zhang Christopher h. Seward Zuowei Wu huiyan Ye Youjun Feng Department of Medical Microbiology and Parasitology Zhejiang University School of Medicine Hangzhou 310058 China Carl R. Woese Institute for Genomic Biology University of Illinois at Urbana-Champaign Urbana IL 61801 USA Department of Veterinary Microbiology and Preventive Medicine Iowa State University Ames IA 50010 USA

Polymyxin acts as an ultimate line of refuge against the severe infections by multidrug-resistant gram- negative pathogens. This conventional idea is challenged dramatically by the recent discovery of mobile colistin resistance gene （mcr-1） is prevalent in food animals and human beings worldwide. More importantly, the mcr-1 gene was found to be co-localized with other antibiotic resistance genes, raising the possibility that super-bugs with pan-drug resistance are emerging. however, little is reported on the genomes of the mcr-l-positive bacterial host reservoirs. here we report genome sequencing of three human isolates of the mcr-l-positive Escherichia coli （E15004, E15015 and E15017） and define general features through analyses of bacterial comparative genomics. Fur- ther genomic mining together with sequence typing allowed us to elucidate that the MCR-l-carrying E. coli E15017 belongs to the sequence type ST648 and copro- duces extended-spectrum β-1actamase （ESBL）. Given the fact that ST648 has been known to associate New Delhi metallo-β-1actamase 1 or ESBL, with either our results highlighted the possibility of ST648 as an epidemic clone with multidrug resistances.

关键词： MCR-1 Extended-spectrum beta-lactam(ESBL) Colistin resistance ST648