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1.
Sci Adv ; 1(3): e1500036, 2015 Apr.
Article in English | MEDLINE | ID: mdl-26601167

ABSTRACT

Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

2.
J Med Chem ; 52(23): 7528-36, 2009 Dec 10.
Article in English | MEDLINE | ID: mdl-19388676

ABSTRACT

In seeking broad-spectrum anticonvulsants to treat epilepsy and other neurological disorders, we synthesized and tested a group of sulfamide derivatives (4a-k, 5), which led to the clinical development of 4a (JNJ-26990990). This compound exhibited excellent anticonvulsant activity in rodents against audiogenic, electrically induced, and chemically induced seizures, with very weak inhibition of human carbonic anhydrase-II (IC(50) = 110 microM). The pharmacological profile for 4a supports its potential in the treatment of multiple forms of epilepsy, including pharmacoresistant variants. Mechanistically, 4a inhibited voltage-gated Na(+) channels and N-type Ca(2+) channels but was not effective as a K(+) channel opener. The pharmacokinetics and metabolic properties of 4a are discussed.


Subject(s)
Amides/chemistry , Amides/pharmacology , Anticonvulsants/chemistry , Anticonvulsants/pharmacology , Sulfonamides/chemistry , Sulfonamides/pharmacology , Thiophenes/chemistry , Thiophenes/pharmacology , Amides/metabolism , Amides/pharmacokinetics , Animals , Anticonvulsants/metabolism , Anticonvulsants/pharmacokinetics , Carbonic Anhydrase II/antagonists & inhibitors , Cell Line , Clinical Trials as Topic , Drug Evaluation, Preclinical , Female , Humans , Male , Mice , Rats , Sulfonamides/metabolism , Sulfonamides/pharmacokinetics , Thiophenes/metabolism , Thiophenes/pharmacokinetics
3.
Drug Metab Dispos ; 32(3): 314-20, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14977865

ABSTRACT

Ezetimibe [1-(4-fluorophenyl)-3(R)-[3-(4-fluorophenyl)-3(S)-hydroxypropyl]-4(S)-(4-hydroxyphenyl)-2-azetidinone] (Zetia; Schering-Plough, Kenilworth, NJ) is the first in a new class of cholesterol-lowering agents known as cholesterol absorption inhibitors. The objective of this study was to identify the isoform(s) of human liver and intestinal UDP-glucuronosyltransferase (UGT) enzymes responsible for the glucuronidation of ezetimibe. The main circulating metabolite of this drug in human plasma is SCH 60663, the phenolic glucuronide conjugate of ezetimibe. SCH 60663 [m/z = 584 Thompsons (Th)] is also the major in vitro metabolite formed by human liver microsomes supplemented with UDP glucuronic acid (UDPGA). In contrast to the liver, human jejunum microsomes supplemented with UDPGA converted ezetimibe to two glucuronides with the same mass (m/z = 584 Th) by liquid chromatography-mass spectrometry. One corresponds to the phenolic glucuronide (1-O-[4-trans-2S,3R)-1-(4-fluorophenyl)-4-oxo-3-[3(S)-hydroxy-3-(4-fluorophenyl)propyl]-2-azetidinyl]phenyl-beta-D-glucopyranuronic acid; SCH 60663) and the other was identified as the benzylic glucuronide of ezetimibe (1-O-[1(S)-(4-fluorophenyl)-3-[1-(4-fluorophenyl)-2(S)-(4-hydroxyphenyl)-4-oxo-3(R)-azetidinyl]propyl]-beta-D-glucopyranuronic acid; SCH 488128). Recombinant human UGT1A1, UGT1A3, and UGT2B15 all exhibited catalytic activity with respect to the formation of the phenolic glucuronide. However, UGT2B7 exclusively formed SCH 488128, a trace metabolite detected in dog and human plasma samples after oral administration of ezetimibe. In conclusion, the formation of SCH 60663 is mediated via UGT1A1, UGT1A3, and UGT2B15, and the formation SCH 488128 is mediated via UGT2B7.


Subject(s)
Anticholesteremic Agents/metabolism , Azetidines/metabolism , Glucuronosyltransferase/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anticholesteremic Agents/pharmacokinetics , Azetidines/pharmacokinetics , Biotransformation , Chromatography, High Pressure Liquid , DNA, Complementary/metabolism , Diclofenac/pharmacology , Enzyme Inhibitors/pharmacology , Ezetimibe , Glucuronides/metabolism , Glucuronosyltransferase/antagonists & inhibitors , Humans , Hydrolysis , In Vitro Techniques , Isoenzymes/metabolism , Jejunum/enzymology , Mass Spectrometry , Microsomes/enzymology , Microsomes, Liver/enzymology
4.
Drug Metab Dispos ; 32(2): 267-71, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14744950

ABSTRACT

Posaconazole (Noxafil, SCH 56592), an orally available broad-spectrum triazole antifungal, is currently in phase III clinical studies for treating serious opportunistic fungal infections. The major in vitro metabolite of posaconazole formed by human liver microsomes supplemented with uridine 5'-diphosphate-glucuronic acid was a glucuronide of posaconazole (m/z877). Screening of 10 cDNA-expressed recombinant human UDP-glucuronosyltransferase (UGT) enzymes showed that only UGT1A4 exhibited catalytic activity with respect to the formation of the glucuronide of posaconazole. The formation of glucuronide by human liver microsomes and UGT1A4 was inhibited by bilirubin, a known inhibitor of UGT1A4. There was a high correlation (r =0.90) between the rate of formation of glucuronide, determined in 10 human liver microsomal samples, and trifluoperazine glucuronidation catalyzed by UGT1A4. These results confirmed that the formation of major posaconazole-glucuronide produced from human liver microsomes was mediated via UGT1A4.


Subject(s)
Antifungal Agents/metabolism , Glucuronides/biosynthesis , Glucuronosyltransferase/metabolism , Triazoles/metabolism , Chromatography, Liquid , Coumarins/metabolism , Glucuronosyltransferase/antagonists & inhibitors , Humans , In Vitro Techniques , Kinetics , Mass Spectrometry , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism , Recombinant Proteins/metabolism , Trifluoperazine/metabolism
5.
Drug Metab Dispos ; 30(4): 430-7, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11901097

ABSTRACT

Ezetimibe [SCH 58235; 1-(4-fluorophenyl)-3(R)-[3-(4-fluorophenyl)-3(S)-hydroxypropyl]-4(S)-(4-hydroxyphenyl)-2-azetidinone], a selective cholesterol absorption inhibitor, is being developed for the treatment of primary hypercholesterolemia. The absorption, metabolism, and excretion of ezetimibe were characterized in eight healthy male volunteers in this single-center, single-dose, open-label study. Subjects received a single oral 20-mg dose of [14C]ezetimibe (approximately 100 microCi) with 200 ml of noncarbonated water after a 10-h fast. Concentrations of radioactivity and/or ezetimibe (conjugated and unconjugated) were determined in plasma, urine, and fecal samples. Ezetimibe was rapidly absorbed and extensively conjugated following oral administration. The main circulating metabolite in plasma was SCH 60663 [1-O-[4-[trans-(2S,3R)-1-(4-fluorophenyl)-4-oxo-3-[3(S)-hydroxy-3-(4-fluorophenyl)propyl]-2-azetidinyl]phenyl]-beta-D-glucuronic acid], the glucuronide conjugate of ezetimibe. Plasma concentration-time profiles of unconjugated and conjugated drug exhibited multiple peaks, indicating enterohepatic recycling. Approximately 78 and 11% of the administered [14C]ezetimibe dose were excreted in feces and urine, respectively, by 240 h after drug administration. Total recovery of radioactivity averaged 89% of the administered dose. The main excreted metabolite was the glucuronide conjugate of ezetimibe. The primary metabolite in urine (0- to72-h composite) was also the glucuronide conjugate (about 9% of the administered dose). Significant amounts (69% of the dose) of ezetimibe were present in the feces, presumably as a result of SCH 60663 hydrolysis and/or unabsorbed drug. No adverse events were reported in this study. A single 20-mg capsule of [(14)C]ezetimibe was safe and well tolerated after oral administration. The pharmacokinetics of ezetimibe are consistent with extensive glucuronidation and enterohepatic recirculation. The primary metabolic pathway for ezetimibe is by glucuronidation of the 4-hydroxyphenyl group.


Subject(s)
Anticholesteremic Agents/metabolism , Anticholesteremic Agents/pharmacokinetics , Azetidines/metabolism , Azetidines/pharmacokinetics , Adult , Anticholesteremic Agents/analysis , Area Under Curve , Azetidines/analysis , Azetidines/blood , Azetidines/urine , Biotransformation , Chromatography, Liquid , Enterohepatic Circulation , Ezetimibe , Feces/chemistry , Humans , Male , Mass Spectrometry , Urine/chemistry
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