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Monthly Archives: May 2012

Glucocorticoids

The Glucocorticoids influence carbohydrate and protein metabolism whereas the mineralocorticoids affect water and electrolyte balance. Glucocorticoids enter target cells by diffusion and bind to specific receptors present in the cell nucleus. Thus they regulate protein synthesis by stimulating messenger RNA formation. Partly the metabolic effects of glucocorticoids may be due …

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Anaphylactic reaction

Anaphylactic reaction is acute, life-threatening IgE-mediated hypersensitivity reaction, provoked by variety of injected, inhaled or ingested foreign substances. Note that the term anaphylactic reaction denotes clinically similar reactions to certain agents e.g. radid-contrast dyes, which are not immunologically mediated. Causes Common precipitating agents for anaphylactic reaction are shown on many sites online, …

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Phagocytosis

Phagocytosis process is the first line of immunological defense to engulf and digest foreign antigens and process them for presentation to  its specific cells. It is mediated by two different cell types i.e. circulatory phagocytes i.e. neutrophils and tissue phagocytes i.e. macrophages, which are derived from monocytes and populate tissues …

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Complement deficiency

Complement deficiency are rarely congenital, seen more commonly as acquired defects due to — a) Deficient production e.g. in newborns, PEM and chronic liver diseases, b) Defective function e.g. in sickle cell disease, c) Increased consumption or loss e.g. in septicemia, bums, SLE and nephrotic syndrome. Clinical features Clinically, complement deficiency …

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Immunoglobulins

Immunoglobulins (IgG) or antibodies are serum proteins, produced by B cells, which a) inactivate, agglutinate antigens for phagocytosis, b) activate complement system for cytolysis. These immunoglobulins may be present on the surface of B- cells (surface immuno globulins) or secreted in extracellular medium (secretory immuno globulins). Depending on their properties and role …

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Antihistamines

Antihistamines – There are two types of histamine antagonists namely H1 receptor antagonists (classical type) and H2 receptor antagonists (used in peptic ulcer). Only H1 receptor antagonists are described below and 112 receptor antagonists will be discussed along with other drugs used for the treatment of peptic ulcer. H1 antihistamines antagonists act by …

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Exogenous (dietary) & Endogenous Lipids

Lipids are heterogeneous group of compounds and are two types, namely, exogenous lipids and endogenous lipids. These are related to fatty acids and are insoluble in water. However, these are soluble in ether and chloroform. These are of three types: a. Simple lipids: These are esters of alcohol and fatty …

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Lipoproteins & their types

Lipoproteins are spherical particles. They transport triglycerides and cholesterol esters through the plasma. Both are non-polar hydrophobic lipids. They form the core of it, which is surrounded by a hydrophilic surface coat of phospholipids, unesterified cholesterol and apoproteins. Due to hydrophilic surface coat, it becomes soluble in plasma and acts …

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