DETECTION OF ANTIVIRAL ANTIBODIES IN SERUM USING AN ELISA TECHNIQUE Essay

DETECTION OF ANTIVIRAL ANTIBODIES IN SERUM USING AN ELISA TECHNIQUE - Essay Example These immunoglobulins are of five types and they are different based on size, charge, amino acid composition and carbohydrate content. the class and the type of immunoglobulin molecule is determined by the heavy chain type. There are two light chains and two heavy chains. There are C and N- terminal in the heavy chains. (Crowther 1995). The N-terminals of the IgG constitute the antigen -binding site. Individuals can become resistant to many infectious diseases by active or passive immunization. The beneficial effects of the immunization are mediated by the antibodies and the effect of immunization is mediated by the immunoassays. (Crowther 2001). The measurement of the antigen and antibody by using sensitive assays are the useful indicators of the immune status. When an infectious agent enters the human body, the component is identified as the foreign particle and antibodies are produced against them. These antibodies interact with the antigens and reduce the load. (Edwards 1999). Th e immunoassay method identifies the antigens, antigen - particles present in the blood and provide the results. Each antibody is specific for an antigen. ELISA is basically of two types: competitive and non-competitive ELISA. ELISA involves two site recognition with two different antibodies (i.e.) an indirect estimation. Competitive ELISA is different from the sandwich ELISA and indirect ELISA. In the first step the unlabelled antibody is incubated on the presence of the antigen. This antigen-antibody bounded is added to the antigen- coated well. The plate is washed and the second antibody specific to the primary antibody is added and the second antibody is coupled to the enzyme. When the substrate is added, the signal is emitted by the remaining enzyme. In this ELISA, if the antigen concentration is very high, then the signal will be very weak. This method is mainly used to test the impure and crude samples. This method is very useful for the detection of HIV. For HIV diagnosis, th e patient's sample and the enzyme-labeled antibody (conjugate) is added simultaneously to the solid phase. HIV antibodies, if present in the sample will bind to the conjugate antibody and reduce the signal. Thus if the color reaction is produced, then it indicates that there are no HIV antibodies in the given sample. Applications of ELISA include screening of the donated blood for viral contaminations( HIV types, Hepatitis B and C, HTLV-1 and 2), measuring the hormone levels( pregnancy(HCG), ovulation( LH), thyroid function ( TSH, T3 and T4), anabolic steroids, hormones), detecting infections( HIV, syphilis, chlamydia, gondii), detecting allergens in foods and toxins in foods, measuring the concentration of the antibodies and detecting illicit drugs ( cocaine, opiates, marijuana, etc.), measuring auto antibodies in autoimmune diseases and measuring rheumatoid factors . (Sheehan 1997). (Wreghitt and Morgan-Capner 1990). Principle When an antibody is linked to the enzyme and allowed t o react with the immobilized antigen, antigen-antibody reaction occurs. This is identified by the production of colour by the substrate enzyme reaction. The antigen is immobilised in either a microtiter plate or on nitrocellulose membrane. An enzyme labelled antibody is added in excess to the system and these binds to the immobilised antigen. Excess antibody is removed by washing and the substrate specific for the

What adjustments to prices could Moscows Kofe Haus Essay

What adjustments to prices could Moscows Kofe Haus (КÐ ¾Ã'„Ð µ Ð ¥Ã °Ã'Æ'Ð ·) restaurant formulate in order to draw more customers during the recession - Essay Example Many assumptions will have to be made due to a lack of good market data, typical of the non-transparent Russian business operating environment. An anecdotal SWOT analysis and literature review was conducted to find solutions to the difficult economic conditions confronting COFFEE HOUSE in the global recession. Marketing strategies and business models from North America were examined. Local competition was surveyed and the target market consumer was profiled. Although the North American market leaders have a dominant world position, they have also suffered during the recession. Not all the strategies and tactics are applicable in the Russian market; but some techniques were adapted with some reservation. COFFEE HOUSEs strength lies in its long history adapting to local market conditions, close contact and development of loyal customers. An evolving strategy must respond to deteriorating purchasing power of consumers and possible loss of market share to new competitors. A shift away from food-based price discounts towards value-based espresso drinks is recommended. The retail hospitality industry is generally vulnerable to downward swings in the economy. Coffee retailers in specific exist in an extremely competive environment and need a strong strategy to survive. The retail coffee market is generally susceptible to fickle consumer tastes and highly price sensitive. Russian coffee and tea franchises are relatively young and it is assumed that much can be learned from experiences in the international arena where a longer track record is evident. Additionally, the hotter competitive scene in mature markets may provide excellent examples for where the Russian market can expect to evolve. Coffee establishments in North America, Europe and Australia have already weathered economic downturns and have applied creative tactics to maintain profitability. These examples, if carefully selected fit unique Russian consumer demands, may provide a attractive pathways