Fetus synthase

Another location with high prostaglandin-synthase activity and low P450 levels is the fetus, and it has been proposed that the teratogenicities of benzo[a]pyrene and phenytoin are due to cyclooxygenase-mediated bioactivation of these agents (45,46). 

Increased HA levels in the bloodstream decrease immune competence.153 Various mechanisms have been invoked. An HA coating around circulating lymphocytes may prevent ligand access to lymphocyte surface receptors.95 96 154 155 The increased HA may represent one of the mechanisms for the immunosuppression in the fetus. The reappearance of high levels of HA in old age may be one of the mechanisms of the deterioration of the immune system in the elderly. The increasing levels of HA with aging may be a reflection of the deterioration of hydrolytic reactions, including the hyaluronidases that maintain the steady state of HA. This is a far more likely mechanism than an increase in HA synthase activity. 

Inhibitors of prostaglandin synthase (aspirin, indomethacin) may delay onset of labour and, in the fetus, cause closure of the ductus arteriosus, patency of which is dependent on prostaglandins. It is probable that drug allergy in the mother can also occur in the fetus and it is possible that the fetus may be sensitised where the mother shows no effect, e.g. neonatal thrombocytopenia from thiazide diuretics. 

A couple comes to the physician s office after having had two sons affected with a similar disease. The first-born son is tall and thin and has dislocated lenses and an IQ of 70. He has also experienced several episodes of deep vein thromboses. The chart mentions deficiency of the enzyme cystathionine-P-synthase, but a diagnosis is not given. The second son was treated from an early age with pyridoxine (vitamin Bg) and is less severely affected. No other family members are affected. While taking a family history, the physician discovers that the parents are first cousins. The 38-year-old mother is pregnant, and amniocentesis has demonstrated that the fetus has a 46,XY karyotype. The risk that the fetus will be affected with the same disease is... 

Feruloylhistamme, 866, 876 4Fe-4S cluster, 2701, 2703 Festuca arundinacea, 164 Festucalvine synthase, 701 Fetus, 374,1319 Fevers, 3795 F-gitogeum, 3666... 

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