Rhône-Poulenc

About: Rhône-Poulenc is a based out in . It is known for research contribution in the topics: Alkyl & Catalysis. The organization has 8909 authors who have published 8934 publications receiving 182241 citations. The organization is also known as: Rhone-Poulenc.

Pharmacokinetics of irinotecan and its metabolites in human blood, bile, and urine

Abstract: Two patients were treated with CPT-11 for colorectal cancer and had a percutaneous biliary catheter for extrahepatic biliary obstruction. The first patient was treated with CPT-11 according to the 100-mg/m2 weekly therapeutic schedule, and the second patient was treated every 3 weeks, with a dose of 350 mg/m2 being given at the first course, after which it was decreased to 300 mg/m2 for the following courses. In plasma, the active identified metabolite of CPT-11, SN-38, occurred mainly in the form of a glucuronide conjugate. CPT-11 was mainly excreted in bile and urine as CPT-11. The cumulative biliary and urinary excretion of CPT-11 and its metabolites (SN-38 and SN-38 glucuronide conjugate) over a period of up to 48 h ranged from 25% (100 mg/m2 weekly) to 50% (300 mg/m2 every 3 weeks). This means that CPT-11 can be excreted under other, not yet identified metabolite forms. CPT-11 is active in vivo, the intensity of its in vitro activity seems rather low. It has been suggested that its major identified metabolite, 7-ethyl-10-hydroxycamptothecin (SN-38) plays a key role in the antitumor activity of CPT-11 [4]. Some in vitro data suggest that SN-38 is 250-to 1,000-fold as potent as CPT-11 in the inhibition of topoisomerase I activity [5]. Although a glucuronide of SN-38 has been found in the bile and urine of rats [3], data have not been reported on humans. However, only Rothenberg et al. [10] have studies the bile concentrations of CPT-11 and SN-38. This report summarizes the pharmacokinetics of CPT-11 and SN-38 and their glucuronide metabolites in the blood, bile, and urine of two patients treated with CPT-11.

Free-flowing pseudoplastic cosmetic compositions/suspensions

Abstract: Storage-stable, pseudoplastic free-flowing cosmetic compositions/formulations, for example shampoos, shower and exfoliating gels and hair lotions, comprise a stable and homogeneous suspension, in water, of water-insoluble particulates, and which further comprise at least one anionic surfactant, at least one nonionic or amphoteric cosurfactant and at least one electrolyte, these surfactants being present in such amounts as to impart pseudoplasticity thereto with a yield point of at least 0.2 Pa and constituting spherulites suspended within a lamellar phase.

The use of human keratinocytes and human skin models for predicting skin irritation.

Abstract: This is the report of the thirty-eighth of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAM’s main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of various types of in vitro tests and their potential uses, and make recommendations about the best ways forward (1). ATLA 27, 723–743, 1999 723

Acute and subacute effects of neuroleptics on dopamine synthesis and release in the rat striatum

Abstract: The effects of acute and subacute treatments with moderate doses of thioproperazine and haloperidol on dopamine synthesis and release have been examined in rat striatal slices. Synthesis and release of dopamine were determined by measuring the rate of formation of 3H-H2O during the conversion of l-3,5-3H-tyrosine into 3H-Dopa and the accumulation of newly synthesized 3H-dopamine in striatal slices and their incubating medium. Possible effects of the treatments on tyrosine striatal levels or tyrosine specific activity were also investigated. Dopamine synthesis rate was markedly accelerated 2.5 hrs after the acute injection of thioproperazine, but was equal to control levels 24 hrs later. The effects of thioproperazine and haloperidol were thus determined 2.5 and 24 hrs after an acute injection and following the last injection of a repeated daily treatment of 11 days. Dopamine synthesis and release were still markedly increased 2.5 hrs after the last injection of the subacute neuroleptic treatments when compared to controls, but these effects were less pronounced than those observed 2.5 hrs after an acute injection of either drug. Conversely, dopamine synthesis and release were significantly decreased 24 hrs after the last injection of the subacute neuroleptic treatments when compared to controls. Two hypotheses are proposed to explain the ments when compared to controls. Two hypotheses are proposed to explain the changes in dopamine synthesis induced by repeated treatments with neuroleptics.