North Eastern Hill University

About: North Eastern Hill University is a education organization based out in Shillong, Meghalaya, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 2318 authors who have published 4476 publications receiving 48894 citations.

A nano-organo catalyzed route towards the efficient synthesis of benzo[b]pyran derivatives under ultrasonic irradiation

Abstract: An efficient, one-pot synthesis of benzo[b]pyrans catalyzed by vitamin B1 functionalized Fe2O3@SiO2 NPs under ultrasonic conditions is reported herein. The nano-organocatalyst was synthesized and characterized by FT-IR, TEM, EDS, powder XRD, etc. Several benzo[b]pyran derivatives were prepared with satisfactory yields and the nanocatalyst was magnetically retrieved and recycled. The salient features of this protocol include convenient work-up procedure, mild reaction conditions, easy catalyst recovery, shorter reaction time and use of green solvents. Ultrasound energy has been meticulously exploited for the synthesis of a nano-organocatalyst as well as for the preparation of several benzo[b]pyran derivatives. The biological activity of the synthesized benzo[b]pyrans were investigated and one of the derivatives was found to demonstrate profound activity in suppressing the side-effects of chlorpyrifos, an insecticide on the morphology of the external gills of the Duttaphrynus melanostictus tadpoles.

Synergistic effect of resveratrol and radiotherapy in control of cancers.

Abstract: Cancers will continue to be a threat to health unless they can be controlled by combinations of treatment modalities. In this review, evaluate the role of resveratrol (RSV) as a radiosensitizing agent was evaluated and underlying mechanisms holistically explored in different cancer models focusing on therapeutic possibilities. The ability of RSV to modify the effect of radiation exposure in normal and cancer cells has indeed been shown quite convincingly, the combination of RSV and IR exhibiting synergistic effects on different cancer cells. This is relevant since controlled exposure to IR is one of the most frequently applied treatments in cancer patients. However, radiotherapy (XRT) treatment regimes are very often not effective in clinical practice as observed in patients with glioma, prostate cancer (PCa), melanoma, for example, largely due to tumour radioresistant properties. Sensitization of IR-induced apoptosis by natural products such as RSV is likely to be relevant in cancer control and treatment. However, all cancers do not respond to RSV+IR in a similar manner. Therefore, for those such as the radioresistant PCa or melanoma cells, the RSV+IR regime has to be very carefully chosen in order to achieve effective and desirable outcomes with minimum toxicity to normal cells. They are reports that the highest concentration of 100 mM RSV and highest dose of 5 Gy IR are sufficient to kill cells by induction of apoptosis, indicating that RSV is effective in radiosensitizing otherwise radioresistant cells. In general, it has been shown in different cancer cells that RSV+XRT effectively act by enhancing expression of anti-proliferative and pro-apoptotic molecules, and inhibiting pro-proliferative and anti-apoptotic molecules, leading to induction of apoptosis through various pathways, and cell death. If RSV+XRT can suppress the signature of cancer stemness, enhance the radiosensitivity by either targeting the mitochondrial functionality or modulating the tumour necrosis factor-mediated or Fas-FasL-mediated pathways of apoptosis in different cancers, particularly in vivo, its therapeutic use in the control of cancers holds promise in the near future.

Enzyme activities in soils: Effects of leaching, ignition, autoclaving and fumigation

Abstract: Cette etude montre qu'il y a au moins trois sites d'activite enzymatique dans le sol A l'interieur des cellules, sur la surface des colloides argilo-humiques et dans la solution du sol Les cellules representent la majeure partie des activites dehydrogenase et urease Les enzymes extracellulaires adsorbees sur les colloides argilo-humiques sont responsables de la majeure partie de l'activite de la phosphatase Les enzymes de la solution du sol representent une tres faible fraction de l'activite enzymatique totale