Deen Dayal Upadhyay Gorakhpur University

About: Deen Dayal Upadhyay Gorakhpur University is a education organization based out in Gorakhpur, Uttar Pradesh, India. It is known for research contribution in the topics: Thermal decomposition & Lymnaea acuminata. The organization has 1032 authors who have published 1591 publications receiving 21734 citations. The organization is also known as: Gorakhpur University.

Ultimobranchial gland of a freshwater teleost, Heteropneustes fossilis, in response to cadmium treatment.

Abstract: Heteropneustes fossilis were subjected to 288 mg/L (0.8 of 96 h LC50) and 72 mg/L (0.2 of 96 h LC50) of cadmium chloride for short-term and long-term experiments, respectively. After sacrificing the fish, the blood was collected on 24, 48, 72, and 96 h in short-term and after 7, 14, 21, and 28 days in long-term experiment and analyzed for plasma calcium levels. Also, ultimobranchial glands were fixed on these intervals. The plasma calcium levels of short-term cadmium-exposed fish remain unchanged after 24 h. The levels exhibit a progressive decrease from 48 h onwards. The fish exposed to cadmium for 7 days exhibit a decrease in the plasma calcium level. Thereafter, the levels progressively decrease till the end of the experiment (28 days). Up to 72 h exposure of the fish to cadmium, the ultimobranchial gland exhibits no histological change. After 96 h, a decrease in the staining response of the cytoplasm of ultimobranchial cells has been noticed. The nuclear volume of these cells records a slight decrease. Up to 14 days of cadmium exposure, there is no change in the histological structure of ultimobranchial gland. After 21 days following the exposure, the ultimobranchial cells exhibit a slight decrease in the staining response of the cytoplasm and the nuclear volume of these cells records a decrease. Following 28 days cadmium exposure the nuclear volume exhibits a further decrease, and degeneration and vacuolization sets in. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.

Redox Homeostasis in Plants Under Arsenic Stress

Abstract: Cellular and intracellular redox balance is a key factor for smooth functioning of enzymes and protein involved in essential metabolic pathways. Metalloid arsenic (As) is toxic to almost all forms of life and is a serious environmental concern due to its wide natural and anthropogenic contamination around the world. Arsenic severely impacts growth of plants and yield of crops grown in As-contaminated soils. Additionally, it gets accumulated in cereal grains, leading to contamination of food, and also hampers the nutrient (essential amino acids and minerals) accumulation grains. Redox imbalance and oxidative stress has been shown to be major cause of As toxicity. Some studies have reported that As also initiates nitrosative stress by inducing reactive nitrogen species. Therefore, understanding the mechanism of redox homeostasis in plants under As stress is important to develop tolerant plants. In the current chapter, the response of known pathways and molecules involved in maintaining cellular redox balance in plant has been discussed in relation to As stress tolerance. Furthermore, the recent studies showing the role of various plant growth regulators (signaling molecules) and glutaredoxins in As stress tolerance has also been discussed.

Prostaglandin E2 Increases Both Osteoblastic and Osteoclastic Activity in the Scales and Participates in Calcium Metabolism in Goldfish

Abstract: Using our original in vitro assay system with goldfish scales, we examined the direct effect of prostaglandin E₂ (PGE₂) on osteoclasts and osteoblasts in teleosts. In this assay system, we measured the activity of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) as respective indicators of each activity in osteoblasts and osteoclasts. ALP activity in scales significantly increased following treatment at high concentration of PGE₂(10⁻⁷ and 10⁻⁶ M) over 6 hrs of incubation. At 18 hrs of incubation, ALP activity also significantly increased in the PGE₂ (10⁻⁹ to 10⁻⁶ M)-treated scale. In the case of osteoclasts, TRAP activity tended to increase at 6 hrs of incubation, and then significantly increased at 18 hrs of incubation by PGE₂ (10(-7) to 10⁻⁶ M) treatment. At 18 hrs of incubation, the mRNA expression of osteoclastic markers (TRAP and cathepsin K) and receptor activator of the NF-κB ligand (RANKL), an activating factor of osteoclasts expressed in osteoblasts, increased in PGE₂ treated-scales. Thus, PGE₂ acts on osteoblasts, and then increases the osteoclastic activity in the scales of goldfish as it does in the bone of mammals. In an in vivo experiment, plasma calcium levels and scale TRAP and ALP activities in the PGE₂-injencted goldfish increased significantly. We conclude that, in teleosts, PGE₂ activates both osteoblasts and osteoclasts and participates in calcium metabolism.

Synthesis and characterization of dendritic polypyrrole silver nanocomposite and its application as a new urea biosensor

Abstract: Polypyrrole and its silver nanocomposite were electrochemically synthesized from aqueous solutions containing pyrrole, potassium chloride (KCl) (system A); pyrrole, KCl, and an anionic surfactant sodium dodecyl sulphate (NaDS) (system B); and pyrrole, silver nitrate, NaDS (system C). Compact and dendritic patterns were observed depending on experimental conditions. The aggregates were characterized by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, high resolution transmission electron microscopic (HRTEM), and thermal studies (TG/DTG). HRTEM studies indicate that the particle size of PPy-Ag nanocomposite is ∼30 nm. TG studies revealed that systems B and C, have different thermal behavior. Potassium ion selective electrodes were constructed using systems A, B, and C. The electrode prepared with PPy-Ag nanocomposite showed nernstian behavior with maximum slope of 57 mV. NH4+ ion-selective electrode was also constructed for this system based on nonactin-impregnated PVC matrix membrane. Urease enzyme was immobilized at the surface of as made NH4+ ion-selective electrode to develop urea biosensor showing good detection limit. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45705.