Isolation and Antimicrobial Susceptibility of Bacteria from Chronic Suppurative Otitis Media Patients in Kerman, Iran

Background: Chronic supportive otitis media (CSOM) is one of the commonest illnesses in ENT practice. This study was conducted to find out the various aerobic microorganisms associated with CSOM and their current antimicrobial susceptibility patterns to commonly used antimicrobials. Methods: samples were collected from 117 clinically diagnosed cases of CSOM and processed according to standard protocols. Results: Out of 117 CSOM cases, 105 (86) showed positive bacterial culture. The Staphylococcus aureus was the commonest aerobic isolate in CSOM. The sensitivity of Staphylococci spp. to commonly used antimicrobials varied from 27.2 for cefixime to 95.5 for gentamicin and coagulase positive. Pseudomonas isolates showed complete (100) resistance to amoxicillin/clavulanate (co-amoxiclave), cloxacillin and cefixime, and high sensitivity to ciprofloxacin (95) and cephalexin (90). Conclusion: An appropriate knowledge of antibacterial susceptibility of microorganisms would contribute to a rational antibiotic use and the success of treatment for chronic supportive otitis media. © Iranian Red Crescent Medical Journal

Production of selenium nanoparticles in Pseudomonas putida KT2440

Selenium (Se) is an essential element for the cell that has multiple applications in medicine and technology; microorganisms play an important role in Se transformations in the environment. Here we report the previously unidentified ability of the soil bacterium Pseudomonas putida KT2440 to synthesize nanoparticles of elemental selenium (nano-Se) from selenite. Our results show that P. putida is able to reduce selenite aerobically, but not selenate, to nano-Se. Kinetic analysis indicates that, in LB medium supplemented with selenite (1 mM), reduction to nano-Se occurs at a rate of 0.444 mmol L−1 h−1 beginning in the middle-exponential phase and with a final conversion yield of 89%. Measurements with a transmission electron microscope (TEM) show that nano-Se particles synthesized by P. putida have a size range of 100 to 500 nm and that they are located in the surrounding medium or bound to the cell membrane. Experiments involving dynamic light scattering (DLS) show that, in aqueous solution, recovered nano-Se particles have a size range of 70 to 360 nm. The rapid kinetics of conversion, easy retrieval of nano-Se and the metabolic versatility of P. putida offer the opportunity to use this model organism as a microbial factory for production of selenium nanoparticles.Universidad de Costa Rica/[809-B5-A68]/UCR/Costa RicaCentro Nacional de Innovaciones Biotecnológicas/[]/CENIBiot/Costa RicaBio-SEA/[]//FranciaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Estructuras Microscópicas (CIEMIC)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuímicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Electroquímica y Energía Química (CELEQ)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA

Horizontal transfer of antibiotic resistance genes among gram negative bacteria in sewage and lake water and influence of some physico-chemical parameters of water on conjugation process

Transfer of antibiotic resistance genes among gram negative bacteria in sewage and lake water and easy access of these bacteria to the community are major environmental and public health concern, The aim of this study was to determine transfer of the antimicrobial resistance genes from resistant to susceptible gram negative bacteria in the sewage and lake water by conjugation process and to determine the influence of some physico-chemical parameters of sewage and lake water on the transfer of these resistance genes. For this reason, we isolated 20 liter of each sewage and lake water from coconut area within university campus and Lingambudi lake respectively in Mysore city, India, during monsoon season and studied different physical parameters of the water samples like pH, temperature, conductivity, turbidity and color as well as chemical parameters like BOD, COD, field DO and total chloride ion. The gram negative bacteria were isolated and identified from the above water samples using microbiological and biochemical methods and their sensitivity to different antibiotics was determined by disc diffusion break point assay. Conjugation between two multiple antibiotic resistant isolates Pseudomonas aeuginosa and E. coli as donor and E. coli Rif' (sensitive to antibiotics) as recipient were carded out in 5ml sterile sewage and lake water All isolates were resistant to Am, moderately resistant to Te and E, while majority were sensitive to Cip, Gm and CAZ antibiotics. Horizontal transfer of antibiotic resistance genes by conjugation process revealed transfer of Gm, Te and E resistant genes from Ps. aeruginosa to E.coli Rif recipient with mean frequency of +/- 2.3 x 10(-4) in sewage and +/- 2.6 x 10(-6) in lake water respectively. Frequency of conjugation in sewage was two fold more as compared to lake water (p <= 0.05). Co-transfer study revealed simultaneous transfer of above resistant markers together to the recipient cells, As the above results indicate, due to selective pressure in sewage (presence of antibiotics), the isolates from sewage were more resistant to different antibiotics as compared to those from lake water Furthermore, these resistance genes can transfer to sensitive bacteria by conjugation. Physico-chemical parameters of water may play role in this process

Microwave-assisted synthesized zinc nanoparticles attenuate cisplatin-induced testicular toxicity in mice

The purpose of this study was to investigate the protective effects of zinc nanoparticles against cisplatin-induced testicular toxicity in mice. Zinc nanoparticles were produced by microwave-assisted synthesis using Lavandula vera extract as reducing agent. Single doses of cisplatin (7 mg/kg, intraperitoneally) and ZnSO4 (10 mg/kg, orally), and various doses of zinc nanoparticles (10 � 50 mg/kg, orally) and vitamin E (100 mg/kg, interaperitoneally) were administered. The protective role of zinc nanoparticles was determined biochemically and histologically. Gradual reduction in malondialdehyde levels and elevation in glutathione levels and in the activities of superoxide dismutase and catalase upon administration of zinc nanoparticles were observed. The pathology of mice treated with cisplatin/vitamin E and cisplatin/zinc nanoparticles were apparently equal, but vitamin E treatment was more effective in lowering oxidative stress markers than zinc nanoparticles. These findings suggest that co-administration of zinc nanoparticles with cisplatin could prevent adverse effects on the male reproductive system via their potential antioxidant properties. © 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group

Rapid and Facile Microwave-Assisted Synthesis of Palladium Nanoparticles and Evaluation of Their Antioxidant Properties and Cytotoxic Effects Against Fibroblast-Like (HSkMC) and Human Lung Carcinoma (A549) Cell Lines

We report here a simple microwave irradiation method (850 W, 3 min) for the synthesis of palladium nanoparticles (Pd NPs) using ascorbic acid (as reducing agent) and sodium alginate (as stabilizer agent). The synthesized nanoparticles were characterized using transmission electron microscopy (TEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), UV-Visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR) techniques. Antioxidant properties and cytotoxic effects of as-synthesized Pd NPs and Pd (II) acetate were also assessed. UV-Vis study showed the formation of Pd NPs with maximum absorption at 345 nm. From TEM analysis, it was observed that the Pd NPs had spherical shape with particle size distribution of 13�33 nm. Based on DPPH radical scavenging activity and reducing power assay, the antioxidant activities of Pd NPs were significantly higher than the Pd (II) acetate (p &lt; 0.05). At the same concentration of 640 μg/mL, the scavenging activities were 32.9 ± 3.2 (Pd (II) acetate) and 27.2 ± 2.1 (Pd NPs). For A549 cells treated 48 h with Pd NPs, Pd (II) acetate, and cisplatin, the measured concentration necessary causing 50 cell death (IC50) was 7.2 ± 1.7 μg/mL, 32.1 ± 2.1 μg/mL, and 206.2 ± 3.5 μg/mL, respectively. On HSkMC cells, the IC50 of the Pd NPs (320 μg/mL) was higher compared to Pd (II) acetate (228.7 ± 3.6 μg/mL), which confirmed lower cytotoxicity of the Pd NPs. © 2019, Springer Science+Business Media, LLC, part of Springer Nature

Bioactive anti-oxidative polycaprolactone/gelatin electrospun nanofibers containing selenium nanoparticles/vitamin E for wound dressing applications

In this study, polycaprolactone/gelatin (PCL/GEL) electrospun nanofibers containing biogenic selenium nanoparticles (Se NPs) and Se NPs/vitamin E (VE) with average diameters of 397.8 nm and 279.5 nm, respectively (as determined by SEM inspection) were prepared and their effect on wound healing was evaluated using in-vivo studies. The energy dispersive X-ray (EDX) mapping, TEM micrograph, and FTIR spectra of the prepared nanofibers strongly demonstrated well entrapment of Se NPs and VE into scaffolds. An amount of 57 Se NPs and 43 VE were gradually released from PCL/GEL/Se NPs/VE scaffold after 4 days immersion in PBS solution (pH 7.4). The both PCL/GEL/Se NPs and PCL/GEL/Se NPs/VE scaffolds supported 3T3 cell proliferation and attachment as confirmed by MTT assay and SEM imaging. Complete re-epithelialization, low level of edema and inflammatory cells in coordination with high level of oriented collagens demonstrated the wound healing activity of PCL/GEL/Se NPs/VE. Besides, significant antioxidant efficacy of PCL/GEL/Se NPs and PCL/GEL/Se NPs/VE scaffolds was demonstrated according to GSH and MDA assays. To sum up, the prepared PCL/GEL/Se NPs/VE scaffold in the present study represented suitable healing effect on animal model which candidate it for further studies. © The Author(s) 2021