Pathogenic mechanisms

Rheumatoid arthritis (RA) is a chronic inflammatory disease of unknown aetiology with some autoimmune features. Current thinking favours the hypothesis that interplay between genetic factors, sex hormones, and possibly an infectious agent or another immune activating agent initiates an autoimmune pathogenic mechanism that culminates in a disease with inflammatory and destructive features. 

The pathogenic mechanisms responsible for the association of musculoskeletal abnormalities with hypercholesterolaemia remain obscure. However, it has been hypothesized that the deposition and modification of lipoprotein components within and around the joint of patients with hyperlipidaemia-associated arthropathy results in a pro-inflammatory response, giving rise to articular disorders (Prete et al., 1993). 

Rathbone, B.J. and Heatley, R.V. (1992). Possible pathogenic mechanisms in Helicobacter pylori infection. In Helicobacter pylori and Gastroduodenal Disease (eds. B.J. Rathbone and R.V. Heatley) pp. 217-223. Blackwell Scientific Pubhcations, Oxford. 

In summary, therefore, the evidence seems convincing that exercise modifies circulating and tissue concentrations of antioxidants and enzyme activities. It is much less certain that the fatigue or damage to skeletal muscle associated with various forms of excessive or unaccustomed exercise is initiated by free radical-mediated degradation. Considerably more work is required in this area to clarify the underlying pathogenic mechanisms. 

In addition to the well-characterized role of iron in catalysing redox interactions, other metallic contaminants, for example, nickel, may also contribute. In vivo toxicity studies have demonstrated the capacity of nickel particulate compounds to induce tumours following intraperitoneal injection (Pott etal., 1987). Such activity is proportional to their phagocytic uptake, and to the associated respiratory burst and generation of PMN-derived reactive oxygen metabolites (ROMs), a proposed pathogenic mechanism (Evans et al., 1992a). 

Sansonetti PJ, Phalipon A M cells as ports of entry for enteroinvasive pathogens Mechanisms of interaction, consequences for the disease process. Semin Immunol 1999 11 193—203. 

In some cases, the primary pathogenic mechanism is an effect on one or more cytoskeletal structures. For example, some widely used chemotherapeutic agents for treatment... 

The unusual multisystemic clinical parallels between DM1 and DM2 suggest a similar pathogenic mechanism. The discovery that DM2 mapped to chromosome 3 and not to the DM1 region of chromosome 19 makes it unlikely that specific gene expression defects cause the common clinical features of the disease. The discovery that a CCTG repeat expansion located on chromosome 3... 

Jarrell, ). T., and Lansbury, P. T.,Jr. (1993). Seeding one-dimensional crystallization of amyloid A pathogenic mechanism in Alzheimer s disease and scrapie Cell 73, 1055-1058. 

Etiologic Agents and Pathogenic Mechanisms in the Acute Byssinotic Reaction... 

Involvement of complement activation in the etiology of the acute byssinotic reaction could explain the pathogenic mechanism of histamine release, non-histamine-mediated bronchoconstriction, chemotaxis, endotoxin and bacterial proteolytic enzyme action. Bronchoconstriction experienced in the acute byssinotic reaction might be attributed to the combined action of C3a and C5a mediated histamine release and non-histamine mediated kinin activity. The presence of PMN in the nasal airways of byssinotics might be explained by the chemotactic action of C5a and the C567 complex. 

Potential etiologic agents in cotton dust that release histamine are shown in Table VII. Some of these are effector molecules having potent biological effects in minute concentrations, i.e. peptides, which may act directly to affect chemotaxis and leukocyte recruitment, and also to release histamine and stimulate respiratory smooth muscle contraction. These bifunctional effector molecules are of major importance in considering pathogenic mechanisms in byssinosis. 

Pathogenic mechanism Therapeutic strategy Drug Company... 

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