Neuroendocrinology of Pyridoxine Deficiency

Veuruenducrim lri v j p .rim, deficienc:v. NEUROSCI BIOBEHAV REV 12(3/4) 189-193. 1988.- Dihydroxyphenylalanine decarboxvlase and 5-hydroxytryptophan decarboxvlase respectively have high and low affinities for pyridoxal phosphate. In the pyridoxinedeficient animal. hypothalamic serotonin content is significantly reduced without any change in catecholamine levels. Hypothalamic neurotransmitters affect the hvpothalamo-pituitary-end organ axes. Specifically, the decrease in hypothalamic serotonin in the pyridoxine-deficient rat results in tertiary hypothyroidism. In addition. pineal function is affected in deficient animals due to decreased synthesis of melatonin.

Hypertension in Pyridoxine Deficiency

Pyridoxal phosphate (PLP) is the coenzyme of various decarboxylases involved in the formation of monoamine urotransmitters such as y-aminobulyric acid (GAE3A), serotonin (5-HT) and dopamine. 1-lowever; in the pyridoxine-deficient rats GABA and 5-HT are decreased in various brain areas including the hypothalamus, with no change in the catecholamine levels. Serotonin and GABA are known to be involved in blood pressure control mechanisms. In this study adult Sprague-Dawley rats placed on a pyridoxine-deficient diet for 8 weeks showed significant hypertension compared with pyridoxine-supplemented controls. This was associated with a general sympathetic stimulation. Treatment of deficient rats with a single dose of pyridoxine (10 mg/kg body weight) reversed the blood pressure to normal levels within 24 h, with concomitant restoration of hypothalamic 5-HT and GABA, as well as the return of plasma norepinephrine to nornr;l levels. The results indicate that there is a cause-and-effect relationship between pyridoxine deficiency and hypertension.

Effect of Pyridoxine Deficiency in Young-Rats on High-Affinity Serotonin and Dopamine Receptors

The high-affinity bindings of [3H]-5-hydroxytryptamine to serotonin S-1 receptors, [3H]-ketanserin to serotonin S-2 receptors in the cerebral cortex, [3H]- fluphenazine to dopamine D-1 receptors, and [3H]-spiroperidol to dopamine D-2 receptors in the corpus striatum were studied in pyridoxine-deficient rats and compared to pyridoxine-supplemented controls. There was a significant increase in the maximal binding (Bmax) of serotonin S-1 and S-2 receptors with a significant decrease in their binding affinities (Kd). However, there were no significant changes either in the maximal binding or binding affinity of striatal dopamine D- 1 and D-2 receptors. Receptor sensitivity seems to correlate negatively with the corresponding neurotransmitter concentrations in the pyridoxine-deficient rats.

Preparation and Properties of Iodine-Doped Radiopaque Natural Rubber

Polymers exhibit low electron density and they are radiolucent. Polymers can be made radiopaque by different techniques. We report a method for the preparation of radiopaque material from natural rubber (NR). NR in its latex form was iodinated. Iodinated natural rubber (INR) was characterized by using UV, thermo gravimetric analysis (TGA), and X-ray images. INR was compounded at high and low temperatures and its physical properties were measured. The low temperature cured samples show good radiopacity and conductivity. The optical density of low temperature cured samples was measured.

Dopamine Receptor Gene Expression In Streptozotocin Induced Diabetic Rats And Its Role In Insulin Secretion

Diabetes Mellitus is a metabolic disorder associated with insulin deficiency, which not.only affects the carbohydrate metabolism but also is associated with various central and peripheral complications. Chronic hyperglycemia during diabetes mellitus is a major initiator of diabetic microvascular complications like retinopathy, neuropathy, The central nervous system (CNS) neurotransmitters play an important role in the regulation of glucose homeostasis. These neurotransmitters mediate rapid intracellular communications not only within the central nervous system but also in the peripheral tissues. They exert their function through receptors present in both neuronal and non neuronal cell surface that trigger second messenger signaling pathways. Dopamine is a neurotransmitter that has been implicated in various central neuronal degenerative disorders like Parkinson's disease and behavioral diseases like Schizophrenia. Dopamine is synthesised from tyrosine, stored in vesicles in axon terminals and released when the neuron is depolarised. Dopamine interacts with specific membrane receptors to produce its effect. Dopamine plays an important role both centrally and peripherally. The recent identification of five dopamine receptor subtypes provides a basis for understanding dopamine's central and peripheral actions . Dopamine receptors are classified into two major groups : DA D1 like and DA D2 like. Dopamine D1 like receptors consists of DA D1 and DA D5 receptors . Dopamine D2 like receptors consists of DA D2, DA D3 and DA D4 receptors. Stimulation of the DA D1 receptor gives rise to increased production of cAMP. Dopamine D2 receptors inhibit cAMP production, but activate the inositol phosphate second messenger system . Impairment of central dopamine neurotransmission causes muscle rigidity, hormonal regulation , thought disorder and cocaine addiction. Peripheral dopamine receptors mediate changes in blood flow, glomerular filtration rate, sodium excretion and catecholamine release. The dopamine D2 receptors increased in the corpus striatum and cerebral cortex but decreased in the hypothalamus and brain stem indicating their involvement in regulating insulin secretion. Dopamine D2 receptor which has a stimulatory effecton insulin secretion decreased in the pancreatic islets during diabetes. Our in vitro studies confirmed the stimulatory role of dopamine D2 receptors in stimulation of glucose induced insulin secretion. A detailed study at the molecular level on the mechanisms involved in the role of dopamine in insulin secretion, its functional modification could lead to therapeutic interventions that will have immense clinical importance.

Professional Services: Civil Liability for Deficiency

This study deals the professional Services civil Liability for deficiency with special reference to medical professionals.the study deals with the characteristics of profession,basis of liability , historical evolution of legal controls on professional services, liability of doctors for negligence under tort law. Expectations to liability for medical negligence are critically evaluated. consent of medical treatment etc are studied

Chemical Evaluation of Selected Organics and Trace Metals in the Mangrove Macroflora Of Cochin

Mangroves are considered to play a significant role in global carbon cycling. Themangrove forests would fix CO2 by photosynthesis into mangrove lumber and thus decrease the possibility of a catastrophic series of events - global warming by atmospheric CO2, melting of the polar ice caps, and inundation of the great coastal cities of the world. The leaf litter and roots are the main contributors to mangrove sediments, though algal production and allochthonous detritus can also be trapped (Kristensen et al, 2008) by mangroves due to their high organic matter content and reducing nature are excellent metal retainers. Environmental pollution due to metals is of major concern. This is due to the basic fact that metals are not biodegradable or perishable the way most organic pollutants are. While most organic toxicants can be destroyed by combustion and converted into compounds such as C0, C02, SOX, NOX, metals can't be destroyed. At the most the valance and physical form of metals may change. Concentration of metals present naturally in air, water and soil is very low. Metals released into the environment through anthropogenic activities such as burning of fossils fuels, discharge of industrial effluents, mining, dumping of sewage etc leads to the development of higher than tolerable or toxic levels of metals in the environment leading to metal pollution. Of course, a large number of heavy metals such as Fe, Mn, Cu, Ni, Zn, Co, Cr, Mo, and V are essential to plants and animals and deficiency of these metals may lead to diseases, but at higher levels, it would lead to metal toxicity. Almost all industrial processes and urban activities involve release of at least trace quantities of half a dozen metals in different forms. Heavy metal pollution in the environment can remain dormant for a long time and surface with a vengeance. Once an area gets toxified with metals, it is almost impossible to detoxify it. The symptoms of metal toxicity are often quite similar to the symptoms of other common diseases such as respiratory problems, digestive disorders, skin diseases, hypertension, diabetes, jaundice etc making it all the more difficult to diagnose metal poisoning. For example the Minamata disease caused by mercury pollution in addition to affecting the nervous system can disturb liver function and cause diabetes and hypertension. The damage caused by heavy metals does not end up with the affected person. The harmful effects can be transferred to the person's progenies. Ironically heavy metal pollution is a direct offshoot of our increasing ability to mass produce metals and use them in all spheres of existence. Along with conventional physico- chemical methods, biosystem approachment is also being constantly used for combating metal pollution

Modeling Of Work-Related Musculoskeletal Disorders In Chemical Process Industry In India

In this modern complex world, stress at work is found to be increasingly a common feature in day to day life. For the same reason, job stress is one of the active areas in occupational health and safety research for over last four decades and is continuing to attract researchers in academia and industry. Job stress in process industries is of concern due to its influence on process safety, and worker‘s safety and health. Safety in process (chemical and nuclear material) industry is of paramount importance, especially in a thickly populated country like India. Stress at job is the main vector in inducing work related musculoskeletal disorders which in turn can affect the worker health and safety in process industries. In view of the above, the process industries should try to minimize the job stress in workers to ensure a safe and healthy working climate for the industry and the worker. This research is mainly aimed at assessing the influence of job stress in inducing work related musculoskeletal disorders in chemical process industries in India