Arthus reaction

Examples of Arthus reaction in the following topics:

• Immune Complex Autoimmune Reactions

  • In immunology, the Arthus reaction is a type of local type III hypersensitivity reaction.
  • Type III hypersensitivity reactions are immune complex-mediated.
  • The Arthus reaction involves the in situformation of antigen/antibody complexes after the intradermal injection of an antigen (as seen in passive immunity).
  • If the animal/patient was previously sensitized (has circulating antibody), an Arthus reaction occurs.
  • Arthus reactions have been infrequently reported after vaccination against diphtheria and tetanus.

• Type III (Immune Complex) Reactions

  • The reaction can take hours, days, or even weeks to develop, depending on whether or not there is immunlogic memory of the precipitating antigen.
  • Skin response to a hypersensitivity of this type is referred to as an Arthus reaction, and is characterized by local erythema and some induration.
  • After an antigen-antibody reaction, the immune complexes can be subject to any of a number of responses, including complement deposition, opsonization, phagocytosis, or processing by proteases.

• Precipitation Reactions

  • Precipitation reactions are serological assays for the detection of immunoglobulin levels from the serum of a patient with infection.
  • Precipitation reactions are based on the interaction of antibodies and antigens.
  • Precipitation reactions differ from agglutination reactions in the size and solubility of the antigen and sensitivity.
  • Antigens are soluble molecules and larger in size in precipitation reactions.
  • Precipitation reactions are less sensitive than agglutination reactions but remain gold standard serological techniques.

• Respiration and Proton Motive Force

  • Most of these smaller reactions are redox reactions themselves.
  • While the overall reaction is a combustion reaction, no single reaction that comprises it is a combustion reaction.
  • Aerobic reactions require oxygen for ATP generation.
  • In eukaryotic cells, the post-glycolytic reactions take place in the mitochondria, while in prokaryotic cells, these reactions take place in the cytoplasm .
  • The overall reaction can be expressed this way:

• Type I (Anaphylactic) Reactions

  • The longer the time since the last exposure to an agent that caused anaphylaxis, the lower the risk of a new reaction.
  • Anaphylaxis is a severe allergic reaction that starts suddenly and affects many body systems.
  • This release is typically associated with an immune system reaction, but may also be caused by damage to cells that are not related to an immune reaction.
  • When anaphylaxis is not caused by in immune response, the reaction is due to an agent that directly damages mast cells and basophils, causing them to release histamine and other substances that are usually associated with an allergic reaction (degranulation).
  • A representation of the signs and symptoms of anaphylaxis that result from an allergic reaction.

• Enzymes Used in Industry

  • Enzymes are biological molecules that catalyze (increase the rates of) chemical reactions.
  • Enzymes are biological molecules that catalyze (increase the rates of) chemical reactions.
  • Like all catalysts, enzymes work by lowering the activation energy for a reaction, thus dramatically increasing the rate of the reaction.
  • Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions.
  • As with all catalysts, enzymes are not consumed by the reactions they catalyze, nor do they alter the equilibrium of these reactions.

• Clostridial and Propionic Acid Fermentation

  • Acetogenesis is a biological reaction wherein volatile fatty acids are converted into acetic acid, carbon dioxide, and hydrogen.
  • Hydrolysis is a chemical reaction wherein particulates are solubilized and large polymers are converted into simpler monomers.
  • Acidogenesis is a biological reaction wherein simple monomers are converted into volatile fatty acids.
  • Acetogenes is a biological reaction wherein volatile fatty acids are converted into acetic acid, carbon dioxide, and hydrogen .
  • Acetogenesis is one of the main reactions of this stage.

• Microbial Ore Leaching

  • The reaction is performed at the bacterial cell membrane.
  • The ferric iron produced in reaction (2) oxidized more sulfide as in reaction (1), closing the cycle and given the net reaction:
  • The net products of the reaction are soluble ferrous sulfate and sulfuric acid.
  • The critical reaction is the oxidation of sulfide by ferric iron.
  • The fungi use the acids that they produce in their metabolic reactions to dissolve the metal.

• Allergic Responses to Drugs

  • An allergic reaction is the body's response to clear a foreign substance.
  • The worst allergic reactions can be very severe and result in anaphylaxis .
  • While the most severe cases can result in anaphylaxis, most reactions are not severe.
  • A representation of the signs and symptoms of anaphylaxis that result from an allergic reaction.
  • Explain the physiology of an immune response responsible for an allergic reaction to drugs

• Amplifying DNA: The Polymerase Chain Reaction

  • The polymerase chain reaction (PCR) is a method by which DNA is amplified.
  • The reaction produces a limited amount of final amplified product that is governed by the available reagents in the reaction, and the feedback-inhibition of the reaction products.
  • Denaturation step: This step is the first regular cycling event and consists of heating the reaction to 94-98 °C.
  • Annealing step: The reaction temperature is lowered to 50-65 °C for 20-40 seconds allowing annealing of the primers to the single-stranded DNA template.
  • This illustrates a PCR reaction to demonstrate how amplification leads to the exponential growth of a short product flanked by the primers. 1.