Enantioselective pharmacokinetics of ketoprofen in calves after intramuscular administration of a racemic mixture

Citalopram (CITA) is available as a racemic mixture or as (+)-(S)-CITA. In humans, CITA is metabolized to demethylcitalopram (DCITA) by CYP2C19, CYP2D6, and CYP3A and to didemethylcitalopram by CYP2D6. There are no data regarding the enzymes involved in CITA and DCITA metabolism in rats. The present study investigated the influence of CYP inhibitors on the enantioselective metabolism of CITA in rats. Male Wistar rats (n = 6) received a single dose of 20 mg·kg–1 CITA after pretreatment with 80 mg·kg–1 quinidine, 10 mg·kg–1 fluvoxamine, 50 mg·kg–1 ketoconazole, or vehicle (control). Blood samples were collected up to 20 h after CITA administration. The CITA and DCITA enantiomers were analyzed by LC-MS/MS using a Chiralcel OD-R column. The kinetic disposition of CITA was enantioselective in rats (AUCS/R ratio = 0.4). Coadministration with quinidine resulted in non-enantioselective inhibition of the metabolism of CITA. Coadministration with fluvoxamine or ketoconazole, however, inhibited only the metabolism of (+)-(S)-CITA, but not of (–)-(R)-CITA when the racemic drug was administered to rats.

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Serum enzyme values following intramuscular administration of lidocaine

Archives of Internal Medicine ◽

10.1001/archinte.134.1.48 ◽

1974 ◽

Vol 134 (1) ◽

pp. 48-49 ◽

Cited By ~ 4

Author(s):

J. C. Zener

Keyword(s):

Intramuscular Administration ◽

Serum Enzyme

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L'esperienza clinica con Levometadone nel trattamento del disturbo da uso di oppiacei

MISSION ◽

10.3280/mis52-2018oa8541 ◽

2019 ◽

pp. 54-57

Author(s):

Marco Riglietta ◽

Paolo Donadoni ◽

Grazia Carbone ◽

Caterina Pisoni ◽

Franca Colombi ◽

...

Keyword(s):

Adverse Events ◽

Real Life ◽

Opioid Use Disorder ◽

Racemic Mixture ◽

Opioid Use ◽

The Real ◽

New Formulation

In Italy, at the end of the 1970s, methadone hydrochloride was introduced for the treatment of opioid use disorder, in the form of a racemic mixture consisting of levomethadone and dextromethadone.In 2015 Levometadone was introduced, a new formulation marketed in Italy for the treatment of opioid use disorder in 2015.The article aims to bring the experience of an Italian Addiction Centre back to the use of this new formulation in the "real life" analyzing the efficacy, the trend of adverse events and pharmacological iterations in a context in which the treated population often uses besides the opiates, cocaine and alcohol, are burdened by a relevant physical and psychic comorbidity and frequently have a prescribed polypharmacy.

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TRANSFORMATION OF Δ5-ANDROSTENE-3,17-DIONE TO A Δ5-3α-HYDROXYSTEROID IN MAN

Acta Endocrinologica ◽

10.1530/acta.0.0410391 ◽

1962 ◽

Vol 41 (3) ◽

pp. 391-394 ◽

Cited By ~ 3

Author(s):

David K. Fukushima ◽

Kenneth I. H. Williams ◽

Barnett Zumoff ◽

T. F. Gallagher

Keyword(s):

Intramuscular Administration ◽

No Conversion

ABSTRACT 3α-Hydroxy-Δ5-androsten-17-one has been isolated following intramuscular administration of Δ5-androstene-3,17-dione to man. There was very little or no conversion to 3β-hydroxy-Δ5 epimer. Significant amounts of androsterone and aetiocholanolone were obtained.

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Conversion of fructose into methyl lactate over SnO2/Al2O3 catalystin flow regime

Catalysis and petrochemistry ◽

10.15407/kataliz2020.30.043 ◽

2020 ◽

pp. 43-47

Author(s):

S.V. Prudius ◽

◽

N.L. Hes ◽

A.M. Mylin ◽

V.V. Brei ◽

...

Keyword(s):

Flow Reactor ◽

Practical Interest ◽

Dimethyl Acetal ◽

Racemic Mixture ◽

Process Conditions ◽

Impregnation Method ◽

Aqueous Methanol ◽

Methyl Lactate ◽

Al2o3 Catalyst ◽

Target Reaction

In recent years, numerous researchers have focused on the development of catalytic methods for processing of biomass-derived sugars into alkyl lactates, which are widely used as non-toxic solvents and are the starting material for obtaining monomeric lactide. In this work, the transformation of fructose into methyl lactate on Sn-containing catalyst in the flow reactor that may be of practical interest was studied. The supported Sn-containing catalyst was ob-tained by a simple impregnation method of granular γ-Al2O3. The catalytic ex-periments were performed in a flow reactor at temperatures of 160-190 °C and pressure of 3.0 MPa. The 1.6-9.5 wt.% fructose solutions in 80% aqueous methanol were used as a reaction mixture. It was found that addition to a reac-tion mixture of 0.03 wt.% potassium carbonate leads to the increase in selec-tivity towards methyl lactate on 15% at 100% conversion of fructose. Prod-ucts of the target reaction С6Н12О6 + 2СН3ОН = 2С4Н8О3 + 2Н2О were ana-lyzed using 13C NMR method. The following process conditions for obtaining of 65 mol% methyl lactate yield at 100% fructose conversion were found: use of 4.8 wt.% fructose solution in 80% methanol, 180 °С, 3.0 МПа and a load on catalyst 1.5 mmol C6H12O6/mlcat/h at contact time of 11 minutes. The cata-lyst productivity is 2.0 mmol C4H8O3/mlcat/h and the by-productі are 1,3-dihydroxyacetone dimethyl acetal (20%) and 5-hydroxymethylfurfural (10%). It should be noted that a racemic mixture of L- and D-methyl lactates has been obtained by conversion of D-fructose on the SnO2/Al2O3 catalyst. The SnO2/Al2O3 catalyst was found to be stable for 6 h while maintaining full fruc-tose conversion at 55–70% methyl lactate selectivity. After regeneration the catalyst completely restores the initial activity.

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