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A Failli

Publications and source records attributed to A Failli.

7 recordsLinked to original sources

A putative sirolimus (rapamycin) effector protein.

Sirolimus (rapamycin), a new immunosuppressive drug, inhibits proliferation of a wide spectrum of T and B cells. The immunosuppressive mechanism of sirolimus is still unclear. We recently isolated a membrane associated protein with an apparent molecular weight of 210 kDa, p210, from cultured Molt 4 cells and BJAB cells and from normal human T cells using an affinity matrix method. The p210 binds to sirolimus:FKBP12 complex, but only at background levels to FKBP12 alone, to FK506:FKBP12 complex, or sirolimus-biotin alone. Among the sirolimus analogs tested, the binding ability of p210 to drug:FKBP12 complexes correlates with the immunosuppressive activity of the drugs, suggesting that p210 is the sirolimus effector protein.

B-Lymphocytes↗

Structure-activity relationships leading to WAY-121,520, a tris aryl-type, indomethacin-based, phospholipase A2 (PLA2)/leukotriene biosynthesis inhibitor.

We were intrigued by reports of the inhibition of phospholipase A2 (PLA2) by indomethacin. In order to increase the potency of the indomethacin system as an inhibitor of PLA2, it was decided to make more lipophilic analogs. Indeed, covalent attachment of a quinoline ring to the methoxy substituent of indomethacin affords WAY-122,220 which is almost an order of magnitude more potent than indomethacin in inhibiting human synovial fluid PLA2 (IC50 = 15 and 145 microM, respectively). The N-p-chloro-benzyl analog of this compound, WAY-121,520, was an even more potent inhibitor of PLA2 (IC50 = 4 microM). Structural analyses and molecular modeling suggest that these compounds may inhibit PLA2 by mimicking arachidonic acid. WAY-121,520 is also a potent leukotriene biosynthesis inhibitor both in the rat PMN and mouse macrophage assays (IC50 = 10 and 4 nM, respectively), possibly acting via a 5-LO (5-lipoxygenase) translocation inhibition mechanism. The multiple actions of WAY-121,520 may contribute to its favorable anti-inflammatory profile.

Animals↗

Antisecretory and antiulcer activities of a potent new histamine H2-receptor antagonist with an intermediate duration of action.

The antisecretory activities of 4-(dimethylamino)- N-[2-[3-[3-(1-piperidinyl)methyl]phenoxy]propyl]amino]- 1,2,5-thiadiazol-4-yl]amino]ethyl]-butanamide, S-oxide (AY-29,315) and ranitidine were determined in the rat, dog and monkey. In conscious, chronically cannulated rats, AY-29,315 was 10 and 208 times more potent than ranitidine as an inhibitor of spontaneous gastric acid secretion by the p.o. and i.v. routes, respectively. Tolerance did not develop in the conscious rat with either compound when administered for 8 consecutive days at doses equivalent to 4 times their antisecretory ED50. In lumen-perfused, anesthetized rats, AY-29,315 i.v. was 44 times more potent than ranitidine as an inhibitor of dimaprit-induced acid secretion. In the gastric fistula dog, AY-29,315 was 7.5 times more potent than ranitidine as an inhibitor of dimaprit-induced secretion by the i.v. route but 3 times less potent by the oral route. In the monkey, against dimaprit, AY-29,315 was 3 and 12 times more potent than ranitidine by the oral and i.v. routes, respectively. p.o./i.v. ratios indicate that, relative to ranitidine, the bioavailability of AY-29,315 by the oral route was low, particularly in the dog. In the dog, at 4 times the oral ED50 dose, the antisecretory effect of ranitidine lasted 190 +/- 3 min, while that of AY-29,315 lasted more than 9 h. AY-29,315 was 8 times more potent than ranitidine as an inhibitor of acetylsalicylic acid-induced ulcers in the rat.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia↗