Platelets inflammation

Platelet activating factor (PAF) was first identified by its ability (at low levels) to cause platelet aggregation and dilation of blood vessels, but it is now known to be a potent mediator in inflammation, allergic responses, and shock. PAF effects are observed at tissue concentrations as low as 10 M. PAF causes a dramatic inflammation of air passages and induces asthma-like symptoms in laboratory animals. Toxic-shock syndrome occurs when fragments of destroyed bacteria act as toxins and induce the synthesis of PAF. This results in a drop in blood pressure and a reduced... 

Vascular constriction/bronchial cons trie tion/allergic inflamm. platelet ag... 

A ubiquitous phospholipid mediator (acetyl-glyceryl-ether-phosphorylcholine) in inflammation. Among others, it stimulates platelet aggregation and causes swelling, smooth contraction or dilation and neutrophil activation. 

Other adverse reactions associated with penicillin are hematopoietic changes such as anemia, thrombocytopenia (low platelet count), leukopenia (low white blood cell count), and bone marrow depression. When penicillin is given orally, glossitis (inflammation of the tongue), stomatitis (inflammation of die mouth), dry mouth, gastritis, nausea, vomiting, and abdominal pain occur. When penicillin is given intramuscularly (IM), there may be pain at die injection site Irritation of the vein and phlebitis (inflammation of a vein) may occur witii intravenous (IV) administration. 

MTX is a potentially toxic dmg that is also used in the treatment of malignancies and psoriasis. Nausea, vomiting, a decreased platelet count, leukopenia (decreased white blood cell count), stomatitis (inflammation of the oral cavity), rash, pruritus, dermatitis, diarrhea, alopecia (loss of hair), and diarrhea may be seen with the administration of this dmg. 

Interactions at surfaces and interfaces also play an essential role in the design and function of clinical implants and biomedical devices. With a few recent exceptions, implants do not attach well to tissue, and the resulting mobility of the tissue-implant interface encourages chroitic inflammation. The result can be a gathering of platelets at the site, leading to a blood clot or to the formation of a fibrous capsule, or scar, around the implant (Figure 3.3). 

These cells respond to a number of different chemoattractants which have specific and distinct receptors on the membrane surface (for recent reviews see Refs. 3 and 4). Such chemoattractants include N-formylpeptides, which are bacterial peptides, and mediators of inflammation such as leukotriene B4, C5a, and platelet activating factor. 

Platelet-activating factor A mediator of platelet aggregation and inflammation that is produced in response to stimuli, such as white blood cells. 

Thrombus An aggregation of fibrin and platelets within a blood vessel. A thrombus often causes vessel obstruction, inflammation, and injury. 

A. indica L. Indian Aristolochia, also known as Indian birthwort, ishvara (Sanskrit), or adagam (Tamil), is a bitter climber native to India. The medicinal material consists of the rhizome, which is to resolve inflammation (India), counteract insect poison, and as an antipyretic (Philippines and Vietnam). The rhizome contains aristolochic acid, which inhibits in vitro and dose-dependent phospholipid hydrolysis by the human synovial fluid phospholipase A2, snake venom phospholipase A2, porcine pancreatic phospholipase A2, and human platelet phospholipase A2 (2). 

Nemmar, A. et al. (2007) Enhanced peripheral fhrombogenidty after lung inflammation is mediated by platelet-leukocyte activation role of P-selectin. Journal of Thrombosis and Haemostasis,... 

It is possible that nematode-secreted AChEs act on alternative substrates to ACh. We had previously suggested, on the basis of structural similarity, that platelet-activating factor (PAF), a potent phospholipid mediator of inflammation, might represent such an alternative substrate (Blackburn and Selkirk, 1992b) but subsequent studies demonstrated that purified AChEs did not cleave PAF, and the enzyme responsible for this activity in secreted products of N. brasiliensis, PAF acetylhydrolase, was purified and defined as a distinct heterodimeric protein (Grigg et al., 1996). Although an open mind on the subject sould be kept, the strict substrate specificity of the nematode-secreted AChEs suggests that they most likely act on ACh alone. 

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