Sustained proliferation in cancer: mechanisms and novel therapeutic targets

Proliferation is an important part of cancer development and progression. This is manifest by altered expression and/or activity of cell cycle related proteins. Constitutive activation of many signal transduction pathways also stimulates cell growth. Early steps in tumor development are associated with a fibrogenic response and the development of a hypoxic environment which favors the survival and proliferation of cancer stem cells. Part of the survival strategy of cancer stem cells may manifested by alterations in cell metabolism. Once tumors appear, growth and metastasis may be supported by overproduction of appropriate hormones (in hormonally dependent cancers), by promoting angiogenesis, by undergoing epithelial to mesenchymal transition, by triggering autophagy, and by taking cues from surrounding stromal cells. A number of natural compounds (e.g., curcumin, resveratrol, indole-3-carbinol, brassinin, sulforaphane, epigallocatechin-3-gallate, genistein, ellagitannins, lycopene and quercetin) have been found to inhibit one or more pathways that contribute to proliferation (e.g., hypoxia inducible factor 1, nuclear factor kappa B, phosphoinositide 3 kinase/Akt, insulin-like growth factor receptor 1, Wnt, cell cycle associated proteins, as well as androgen and estrogen receptor signaling). These data, in combination with bioinformatics analyses, will be very important for identifying signaling pathways and molecular targets that may provide early diagnostic markers and/or critical targets for the development of new drugs or drug combinations that block tumor formation and progression

Aqueous extract of Terminalia arjuna prevents carbon tetrachloride induced hepatic and renal disorders

BACKGROUND: Carbon tetrachloride (CCl(4)) is a well-known hepatotoxin and exposure to this chemical is known to induce oxidative stress and causes liver injury by the formation of free radicals. Acute and chronic renal damage are also very common pathophysiologic disturbances caused by CCl(4). The present study has been conducted to evaluate the protective role of the aqueous extract of the bark of Termnalia arjuna (TA), an important Indian medicinal plant widely used in the preparation of ayurvedic formulations, on CCl(4 )induced oxidative stress and resultant dysfunction in the livers and kidneys of mice. METHODS: Animals were pretreated with the aqueous extract of TA (50 mg/kg body weight) for one week and then challenged with CCl(4 )(1 ml/kg body weight) in liquid paraffin (1:1, v/v) for 2 days. Serum marker enzymes, namely, glutamate pyruvate transaminase (GPT) and alkaline phosphatase (ALP) were estimated in the sera of all study groups. Antioxidant status in both the liver and kidney tissues were estimated by determining the activities of the antioxidative enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); as well as by determining the levels of thiobarbutaric acid reactive substances (TBARS) and reduced glutathione (GSH). In addition, free radical scavenging activity of the extract was determined from its DPPH radical quenching ability. RESULTS: Results showed that CCl(4 )caused a marked rise in serum levels of GPT and ALP. TBARS level was also increased significantly whereas GSH, SOD, CAT and GST levels were decreased in the liver and kidney tissue homogenates of CCl(4 )treated mice. Aqueous extract of TA successfully prevented the alterations of these effects in the experimental animals. Data also showed that the extract possessed strong free radical scavenging activity comparable to that of vitamin C. CONCLUSION: Our study demonstrated that the aqueous extract of the bark of TA could protect the liver and kidney tissues against CCl(4)-induced oxidative stress probably by increasing antioxidative defense activities

Tradition of Clan names and conservation among the <i style="">Oraons</i> of Chhattishgarh

224-226The Oraons of Chattisgarh have a tradition of totemism; name their clans after plants, animals, and other objects of their daily needs or environment. They attach some special significance like faith, taboos or other practices to emphasize the importance of these things in their survival and the need for their conservation. The folk of those clans do not harm these species, and protect them from any damage. Examples of names of some animals, plants, and other objects common among the Oraons of Chattisgarh are given. Such traditions helping in conservation of biodiversity, and natural resources have been discussed

Integrated gas dynamic and thermodynamic computational modeling of multicylinder 4-stroke spark ignition engine using gasoline as a fuel

This paper presents a computational tool for the evaluation of engine performance and exhaust emissions for four stroke multi-cylinder spark ignition engine which uses gasoline as a fuel. Gas dynamics flow in multi-cylinder intake and exhaust systems are modeled by using one-dimensional unsteady compressible flow equations. The hyperbolic partial differential equations are transferred into a set of ordinary differential equations by using method of characteristics and solved by finite difference method. Compatibility relationships between local fluid velocity and sonic velocity are expressed in terms of Riemann variables, which are constant along the position characteristics. The equations are solved numerically by using rectangular grid in the flow direction and time. In this model nitric oxide concentration is predicted by using the rate kinetic model in the power cycle and along the exhaust pipes. Carbon monoxide is computed under chemical equilibrium condition and then empirical adjustment is made for kinetic behaviors based upon experimental results. A good agreement is obtained in the comparison of computed and experimental results of instantaneous cylinder pressure, manifold pressure and temperature, and nitric oxide and carbon monoxide emissions level