Linezolid Susceptibility And Potential Resistance Mechanisms Among Mrsa Isolated From Two Major Public Hospitals In Malaysia

Linezolid is the first antibiotic of a new structural class, the oxazolidinones, to be approved for clinical use in 35 years. This antimicrobial agent is broadly effective against drug-resistant gram-positive pathogens which commonly cause infections. Linezolid merupakan antibiotik pertama dari kelas struktur baru, oksazolidinon, yang telah diluluskan untuk kegunaan klinikal setelah 35 tahun. Ejen anti-mikrob ini berkesan secara meluas terhadap patogen gram-positif rintang-antibiotik yang sering menjadi punca jangkitan bakteria

Exploring Various Techniques for the Chemical and Biological Synthesis of Polymeric Nanoparticles

Nanoparticles (NPs) have remarkable properties for delivering therapeutic drugs to the body’s targeted cells. NPs have shown to be significantly more efficient as drug delivery carriers than micron-sized particles, which are quickly eliminated by the immune system. Biopolymer-based polymeric nanoparticles (PNPs) are colloidal systems composed of either natural or synthetic polymers and can be synthesized by the direct polymerization of monomers (e.g., emulsion polymerization, surfactant-free emulsion polymerization, mini-emulsion polymerization, micro-emulsion polymerization, and microbial polymerization) or by the dispersion of preformed polymers (e.g., nanoprecipitation, emulsification solvent evaporation, emulsification solvent diffusion, and salting-out). The desired characteristics of NPs and their target applications are determining factors in the choice of method used for their production. This review article aims to shed light on the different methods employed for the production of PNPs and to discuss the effect of experimental parameters on the physicochemical properties of PNPs. Thus, this review highlights specific properties of PNPs that can be tailored to be employed as drug carriers, especially in hospitals for point-of-care diagnostics for targeted therapies

Biomedical Applications of Polyhydroxyalkanoate in Tissue Engineering

Tissue engineering technology aids in the regeneration of new tissue to replace damaged or wounded tissue. Three-dimensional biodegradable and porous scaffolds are often utilized in this area to mimic the structure and function of the extracellular matrix. Scaffold material and design are significant areas of biomaterial research and the most favorable material for seeding of in vitro and in vivo cells. Polyhydroxyalkanoates (PHAs) are biopolyesters (thermoplastic) that are appropriate for this application due to their biodegradability, thermo-processability, enhanced biocompatibility, mechanical properties, non-toxicity, and environmental origin. Additionally, they offer enormous potential for modification through biological, chemical and physical alteration, including blending with various other materials. PHAs are produced by bacterial fermentation under nutrient-limiting circumstances and have been reported to offer new perspectives for devices in biological applications. The present review discusses PHAs in the applications of conventional medical devices, especially for soft tissue (sutures, wound dressings, cardiac patches and blood vessels) and hard tissue (bone and cartilage scaffolds) regeneration applications. The paper also addresses a recent advance highlighting the usage of PHAs in implantable devices, such as heart valves, stents, nerve guidance conduits and nanoparticles, including drug delivery. This review summarizes the in vivo and in vitro biodegradability of PHAs and conducts an overview of current scientific research and achievements in the development of PHAs in the biomedical sector. In the future, PHAs may replace synthetic plastics as the material of choice for medical researchers and practitioners

Rapid and sensitive detection of Salmonella with reduced graphene oxide-carbon nanotube based electrochemical aptasensor

Rapid detection of foodborne pathogens is crucial as ingestion of contaminated food products may endanger human health. Thus, the objective of this study was to develop a biosensor using reduced graphene oxide-carbon nanotubes (rGO-CNT) nanocomposite via the hydrothermal method for accurate and rapid label-free electrochemical detection of pathogenic bacteria such as Salmonella enterica. The rGO-CNT nanocomposite was characterized using Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction and transmission electron microscopy. The nanocomposite was dropped cast on the glassy carbon electrode and further modified with amino-modified DNA aptamer. The resultant ssDNA/rGO-CNT/GCE aptasensor was then used to detect bacteria by using differential pulse voltammetry (DPV) technique. Synergistic effects of aptasensor was evident through the combination of enhanced electrical properties and facile chemical functionality of both rGO and CNT for the stable interface. Under optimal experimental conditions, the aptasensor could detect S. Typhimurium in a wide linear dynamic range from 101 until 108 cfu mL−1 with a 101 cfu mL−1 of the limit of detection. This aptasensor also showed good sensitivity, selectivity and specificity for the detection of microorganisms. Furthermore, we have successfully applied the aptasensor for S. Typhimurium detection in real food samples. © 2019 Elsevier Inc

Synthesis, characterization and cytotoxicity studies of nanocrystalline cellulose from the production waste of rubber-wood and kenaf-bast fibers

In the present study, nanocrystalline cellulose (NCC) was successfully prepared from raw rubberwood fiber (RRaw) and raw Kenaf-bast fiber (KRaw) via a series of multi-step chemical-mechanical purification techniques, namely, alkalization treatment, hydrogen peroxide bleaching and acid hydrolysis. The obtained nanocellulose yields were 27.51% and 32.53% for RRaw and KRaw, respectively. The crystallinity index of the RRaw and KRaw based nanocellulose increased from 61.21% to 74.34% and 54.12% to 73.19%, respectively, after acid hydrolysis. Morphological characterization by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) clearly showed the formation of rod-shaped NCC with an average diameter of 5.14 ± 1.91 nm and 5.27 ± 2.38 nm for RRaw and KRaw, respectively. Their size distributions significantly reduced compared to raw cellulose biomass fiber and extracted cellulose (EC). Furthermore, changes in the Fourier transform-infrared (FTIR) peaks showed that amorphous regions (e.g. hemicelluloses and lignin) were successfully removed from the fibre surface. The thermogravimetric analysis (TGA) of as-synthesized NCC confirmed its thermostability. Cytotoxicity tests demonstrated that NCC did not exhibit cellular toxicity upon exposure to macrophages (RAW 264.7) and HaCaT cells up to 700 µg mL−1. © 2019 Elsevier Lt