adj. of, relating to, or causing *lysis. For example, bone metastases that involve lysis (destruction) of normal bone, typically seen in multiple *myeloma, are described as lytic.
mA symbol for *milliamp.
MabThera n. see rituximab.
A VIRUS which invades a bacterium (see BACTERIA). Containing either single-stranded or double-stranded DNA or RNA, a particular phage generally may infect one or a limited number of bacterial strains or species. After infection, once phage nucleic acid has entered the host cell, a cycle may result whereby the bacteria are programmed to produce viral components, which are assembled into virus particles and released on bacterial lysis (disintegration). Other (temperate) phages induce a non-lytic, or lysogenic, state, in which phage nucleic acid integrates stably into and replicates with the bacterial chromosome. The relationship can revert to a lytic cycle and production of new phages. In the process the phage may carry small amounts of donor bacterial DNA to a new host: the production of diphtheria toxin by Corynebacterium diphtheriae and of erythrogenic toxin by Streptococcus pyogenes are well-known examples of this e?ect.... bacteriophage
This is part of the body’s defence mechanism that comprises a series of 20 serum peptides (see PEPTIDE). These are sequentially activated to produce three signi?cant effects: ?rstly, the release of small peptides which provoke in?ammation and attract phagocytes (see PHAGOCYTE); secondly, the deposition of a substance (component C3b) on the membranes of invading bacteria or viruses, attracting phagocytes to destroy the microbes; thirdly, the activation of substances that damage cell membranes – called lytic components – which hasten the destruction of ‘foreign’ cells. (See IMMUNOLOGY.)... complement system
(multiple myeloma, myelomatosis) n. a malignant disease of the bone marrow, characterized by two or more of the following criteria: (1) the presence of an excess of abnormal malignant plasma cells in the bone marrow; (2) typical *lytic deposits in the bones on X-ray, giving the appearance of holes; (3) the presence in the serum of an abnormal gammaglobulin, usually IgG (an immunoglobulin; see paraprotein). *Bence-Jones protein may also be found in the serum or urine. The patient may complain of tiredness due to anaemia and of bone pain and may develop pathological fractures. Treatment is usually with such drugs as steroids, melphalan, cyclophosphamide, or thalidomide with local radiotherapy to particular areas of pain. See also plasmacytoma.... myeloma
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