STEPS IN THE PROCESS OF NEW DRUG DEVELOPMENT

This review determines the various stages of drug discovery, pre clinical trials and clinical trials. This process involves the identification of chemical compound, synthesis, characterization, validation, optimization, screening and assay for therapeutic efficacy. Once a new drug target or promising molecule has been identified the process of moving from the science laboratory to the pre clinical to clinical trials have been discussed in this article. The main aim of this process is identifying the chemical compound which is therapeutically useful in treating and curing the disease. The most common steps in the development of a new drug are discovery or synthesis of a potential new drug compound or elucidation of a new drug. Once a chemical compound has shown its therapeutic efficacy in these investigations, it will initiate the process of drug development earlier to clinical trials. The drug development from initial idea to the market is a very complex process which can take upto 5 to 10 years and cost of $17 billion. Due to high budget of research & development and clinical trials drug discovery process is the most expensive. The average time taken for the drug discovery is almost 12 -15 years to develop a single new compound and enter into market

Nanoselenium Enhanced Wheat Resistance to Aphids by Regulating Biosynthesis of DIMBOA and Volatile Components

Aphid s are one of the most destructive insects in many cultivated plants including wheat, which can cause significant yield loss and damage the quality of agricultural products. Therefore, it is essential to control the occurrence of aphids during wheat growth. Previous studies reported the alterations in the resistance of wheat to pests induced by several external factors such as nutrients in soils and nano-carbonaceous materials. In this study, nanoselenium (nano-Se) was sprayed on wheat leaves at several concentration levels (1.0, 5.0, and 20 mg/L). Nano-Se (5.0 mg/L) could significantly reduce Sitobion avenae number (36%) compared with the control . The foliar application of nano-Se was found to enhance the antioxidation capacity by reducing MDA concentration and increasing GSH-Px, CAT, GSH, Pro and VE concentrations. Phenylpropane pathway was activated after the application of nano-Se, with significantly increasing apigenin and caffeic acid concentrations. The high-level expression of the related genes ( TaBx1A , TaBx3A , TaBx4A, TaASMT2, and TaCOMT ) induced the increasing melatonin concentration by 88.6% and DIMBOA concentration by 64.3%. Different ratios of the secondary metabolites to nano-Se were conducted to examine the effects on wheat resistance to the Sitobion avenae . The results revealed the combination of nano-Se and melatonin can achieve the best overall performance by reducing the Sitobion avenae infection by 52.2%. The results from this study suggest that the coordinative applications nano-Se and melatonin combination could be more effectively improve the wheat resistance to aphids via promotion of volatile organic compound synthesis and modulation in phenylpropane and indole metabolism pathways.