Dengue scenario: Chennai perspective-a six-year study (2009-2014).

Dengue is a public health problem with an increasing global incidence and geographic distribution in almost all tropical and subtropical countries, with a transition from epidemic to endemic occurrence. In this study, we report a six-year analysis (2009-2014) performed at the Department of Virology, King Institute of Preventive Medicine, Chennai, Tamil Nadu, India. Our data confirm earlier findings that dengue is highly endemic in Chennai. In the present study, 10,099 serum samples from suspected dengue cases were tested for IgM ELISA (NIV Capture) and IgG Panbio ELISA (Australia). Of these suspected cases 6,798 and 3,301 were pediatric and adult cases, respectively, and 1,927 (19.08 %) were confirmed serologically as dengue. Of these, 1,752 (25.7 %) and 175 (5.3 %) were pediatric and adult cases, respectively. The aim of this study was to highlight the occurrence of DHF and DSS, mainly among the pediatric population, in which the infection causes higher mortality and morbidity. The overall positivity was higher in the pediatric group than in the adults. Detection of both IgM and IgG positivity will be useful for monitoring infection rates, the disease spectrum, and the prevalence of the different serotypes, which will give us insight about the circulating serotypes and pathogenicity. These data will be valuable for providing an early warning to predict an impending epidemic leading to major clinical manifestations of DHF and DSS.

Effect of organic-ligands on the toxicity profiles of CdS nanoparticles and functional properties.

CdS nanoparticles are one among the most promising agents for fluorescent imaging. Hence, it is essential to develop new strategies to overcome the cytotoxicity of these nanoparticles. Surface modification is one of the simplest and effective techniques. This paper assesses the effect of surface modification on toxicity of the CdS nanoparticles. Unmodified CdS and surface-modified CdS nanoparticles were synthesized in an aqueous medium using a wet chemical route at room temperature. The surface modification of the CdS nanoparticles with polyvinylpyrrolidone (PVP) and cysteine was confirmed using infrared absorption studies. The diameters of unmodified CdS, PVP-modified CdS, and cysteine-modified CdS nanoparticles were determined using HRTEM. They exhibited luminescence in the range from 500 to 800 nm. The cytotoxic effects of these CdS nanoparticles were investigated in cultures of Vero cells. The results indicated that Vero cell viability was higher for the surface-modified CdS nanoparticles than for the unmodified CdS nanoparticles. The reduction in the toxicity was related to the nature of the capping agents used for the surface modification, and the particle size.