Search results for "Dosage"
showing 10 items of 516 documents
Sequential injection analysis (SIA)-chemiluminescence determination of indomethacin using tris[(2,2'-bipyridyl)]ruthenium(III) as reagent and its app…
2006
Abstract Automated sequential injection (SIA) method for chemiluminescence (CL) determination of nonsteroidal anti-inflammatory drug indomethacin ( I ) was devised. The CL radiation was emitted in the reaction of I (dissolved in aqueous 50% v/v ethanol) with intermediate reagent tris(2,2′-bipyridyl)ruthenium(III) (Ru(bipy) 3 3+ ) in the presence of acetate. The Ru(bipy) 3 3+ was generated on-line in the SIA system by the oxidation of 0.5 mM tris(2,2′-bipyridyl)ruthenium(II) (Ru(bipy) 3 2+ ) with Ce(IV) ammonium sulphate in diluted sulphuric acid. The optimum sequence, concentrations, and aspirated volumes of reactant zones were: 15 mM Ce(IV) in 50 mM sulphuric acid 41 μL, 0.5 mM Ru(bipy) 3 …
Physico-chimie des lipopolysaccharides et réponse inflammatoire : rôle des lipoprotéines
2014
LPS is a potent bacterial pro-inflammatory agent, consisting of hydrophilic, polysaccharide part and of a lipid A which is considered like active moiety. Nevertheless, the O chain of LPS influences their aggregation in aqueous media. Therefore, our goal has been to determine the role of O chain on the LPS biological and physiopathological effects. Our work was organized according to three main axes, and led to the following findings :- development of a new LPS assay by LC-MS/MS. The combination of this new technique with LAL test allowed us to calculate an inactivation ratio which reflects the ability of host organism to inactivate LPS, especially through their transfer to HDL by PLTP. The …
Monte Carlo evaluation of kerma in an HDR brachytherapy bunker
2004
In recent years, the use of high dose rate (HDR) after-loader machines has greatly increased due to the shift from traditional Cs-137/Ir-192 low dose rate (LDR) to HDR brachytherapy. The method used to calculate the required concrete and, where appropriate, lead shielding in the door is based on analytical methods provided by documents published by the ICRP, the IAEA and the NCRP. The purpose of this study is to perform a more realistic kerma evaluation at the entrance maze door of an HDR bunker using the Monte Carlo code GEANT4. The Monte Carlo results were validated experimentally. The spectrum at the maze entrance door, obtained with Monte Carlo, has an average energy of about 110 keV, m…
Phantom development for daily checks in electron intraoperative radiotherapy with a mobile linac.
2020
Abstract Purpose IORT with mobile linear accelerators is a well-established modality where the dose rate and, therefore, the dose per pulse are very high. The constancy of the dosimetric parameters of the accelerator has to be checked daily. The aim of this work is to develop a phantom with embedded detectors to improve both accuracy and efficiency in the daily test of an IORT linac at the surgery room. Methods The developed phantom is manufactured with transparent polymethyl methacrylate (PMMA), allocating 6 parallel-plate chambers: a central one to evaluate the on-axis beam output, another on-axis one placed at a fixed depth under the previous one to evaluate the energy constancy and four…
Ion-exchange fibers and drugs: a transient study.
2003
The objective of this study was to theoretically model and experimentally measure the kinetics and extent of drug release from different ion-exchange materials using an in-house-designed flow-cell. Ion-exchange fibers (staple fibers and fiber cloth) were compared with commercially available ion-exchange materials (resins and gels). The functional ion-exchange groups in all the materials were weak -COOH or strong -SO3H groups. The rate and extent of drug release from the fibers (staple fiber>fiber cloth) was much higher than that from the resin or the gel. An increase in the hydrophilicity of the model drugs resulted in markedly higher rates of drug release from the fibers (nadolol>metoprolo…
In vitro pulsatile and continuous transdermal delivery of buserelin by iontophoresis
1993
Abstract Transdermal delivery of buserelin, a nonapeptide, from hydroxyethylcellulose hydrogel through isolated human stratum comeum was studied. In vitro studies were carried out in a drug release apparatus (DAB 10/USP XII) using self designed rotary disk cells equipped with platinum electrodes. Different forms of current were examined. A pulsatile application of continuous current resulted in a step-like permeation profile. Different on/off ratios (5 min/55 min; 10 min/50 min; 15 min/45 min)) were studied. When continuous non-interrupted current with different current densities (0.1–0.3 mA·cm −2 ) was applied, linear dependence of the final cumulative amount of buserelin on current durati…
Influence of cryogenic grinding on properties of a self-emulsifying formulation
2003
Abstract Recently, self-emulsifying drug delivery systems (SEDDS) have been developed as a method to deliver lipophilic drugs. Gelucire® 44/14 is an excipient, from the lauroyl macrogolglycerides family, producing a fine oil-in-water emulsion when introduced into an aqueous phase under gentle agitation as SEDDS, improving thereby solubility of poorly water-soluble drugs and their bioavailability. The aims of this study were to process Gelucire® 44/14 into a powder by cryogenic grinding to produce solid oral dosage forms and to investigate influence of this process on different properties of a formulation made of Gelucire® 44/14 and ketoprofen (90/10). Cryogenic grinding produced Gelucire® 4…
Colonic drug delivery: influence of cross-linking agent on pectin beads properties and role of the shell capsule type.
2006
For colonic delivery, pectin beads obtained by ionotropic gelation method have been already reported as an interesting approach. This study investigated the influence of the cross-linking agent (calcium or zinc) and the type of shell capsule used (classical or enteric capsules) on pectin beads properties and on their performance to target the colon (in vitro dissolution studies with subsequent pH change to mimic overall gastro-intestinal tract). Zinc pectinate beads seemed to be relatively similar to calcium's ones in morphological point, except on the surface aspect. When beads were introduced in classical hard capsules, ketoprofen release was not significantly different between CPG and ZP…
Association of mechanical bowel preparation with oral antibiotics and anastomotic leak following left sided colorectal resection: an international, m…
2018
INTRODUCTION: The optimal bowel preparation strategy to minimise the risk of anastomotic leak is yet to be determined. This study aimed to determine whether oral antibiotics combined with mechanical bowel preparation (MBP+Abx) was associated with a reduced risk of anastomotic leak when compared to mechanical bowel preparation alone (MBP) or no bowel preparation (NBP).METHODS: A pre-planned analysis of the European Society of Coloproctology (ESCP) 2017 Left Sided Colorectal Resection audit was performed. Patients undergoing elective left sided colonic or rectal resection with primary anastomosis between 1 January 2017 and 15 March 2017 by any operative approach were included. The primary out…
Safety and efficacy of intensity-modulated radiotherapy in the management of spermatic cord sarcoma.
2017
International audience; Purpose. - Spermatic cord sarcoma is a rare disease, which management remains controversial due to the lack of guidelines. The standard therapeutic approach is surgical: wide soft-tissue resection with radical inguinal orchidectomy, The diagnosis is made during the analysis of the specimen. The high rate of local recurrence indicates adjuvant radiotherapy of the tumor bed. The aim of this series is to determine the efficacy and safety of postoperative intensity-modulated radiotherapy for spermatic cord sarcomas. Patients and methods. - Our series included five consecutive cases of spermatic cord sarcoma treated between 2011 and 2014. The indications for radiotherapy …