Search results for " Drug"
showing 10 items of 3138 documents
The role of drug sequence in therapeutic selectivity of the combination of 5-fluorouracil and cis-platin.
1989
The therapeutic efficacy of 5-fluorouracil (FUra) and cis-dichlorodiamine-platinum (cis-DDP) in mice bearing transplantable leukemia and solid tumors was evaluated using different sequences of combination of these agents. The optimal sequence was cis-DDP administered 24 h after FUra. The administration of FUra at its maximally tolerated dose (MTD) followed 24 h later by low doses of cis-DDP yielded less toxicity and higher response rate against L1210 and colon 26 than the administration of these two agents in the opposite sequence or concurrently at the MTD. The sequence of administration of these two agents was not therapeutically important when the antitumor activity was evaluated against…
Alendronate-related oral mucosa ulcerations
2000
Alendronate is widely used in the treatment of osteoporosis and other bone diseases. Although it is considered a well-tolerated drug, there are numerous reports of adverse effects on the mucosa in the upper aerodigestive tract, with oesophagitis as the most common complication. The strict regulations for the proper administration of the drug indicate that these side effects might well be the result of a direct, irritant mechanism on the upper aerodigestive tract. We present two clinical cases of patients who developed extensive palatal ulcers as a result of taking alendronate. We discuss possible mechanisms implicated in the production of the ulcers and some clinical factors of interest.
Entrapment of an EGFR inhibitor into nanostructured lipid carriers (NLC) improves its antitumor activity against human hepatocarcinoma cells
2014
Background: In hepatocellular carcinoma (HCC), different signaling pathways are de-regulated, and among them, the expression of the epidermal growth factor receptor (EGFR). Tyrphostin AG-1478 is a lipophilic low molecular weight inhibitor of EGFR, preferentially acting on liver tumor cells. In order to overcome its poor drug solubility and thus improving its anticancer activity, it was entrapped into nanostructured lipid carriers (NLC) by using safe ingredients for parenteral delivery. Results: Nanostructured lipid carriers (NLC) carrying tyrphostin AG-1478 were prepared by using the nanoprecipitation method and different matrix compositions. The best system in terms of mean size, PDI, zeta…
Lipid Nanoparticles for Drug Targeting to the Brain
2012
In this chapter, the main production methods of lipid nanostructures such as solid lipid nanoparticles and nanostructured lipid carriers, and their application are described. In particular, we describe the strategies commonly used to obtain lipid nanoparticles to overcome the blood-brain barrier (BBB) for the treatment of several brain diseases. The use of these carriers as targeted drug delivery systems is associated with many advantages that include excellent storage stability, easy production without the use of any organic solvent, the possibility of steam sterilization and lyophilization, and large scale production. They exhibit good stability during long-term storage, consist of physio…
Modeling of Cell Membrane Targeting: Specific Recognition, Binding, and Protein Domain Formation in Ligand-Containing Model Biomembranes
1990
Drug delivery systems are designed to assist, accelerate, and control transport of pharmacologically active agents from sites of administration to specified targets in organs and tissues. So-called controlled drug delivery systems are intended to maintain continuously efficacious drug concentrations in vivo, either locally or systemically, over longer time periods. They should provide constant dosage levels above a minimum level of efficacy yet below mandated toxicity levels — a significant advantage over many conventional systemically administered formulations. Site-specific targeting of drugs, particularly those agents which prove highly toxic in small doses, can be utilized to maintain t…
Determination of the enantiomeric composition of amphetamine, methamphetamine and 3,4-methylendioxy-N-methylamphetamine (MDMA) in seized street drug …
2021
Amphetamine (speed), methamphetamine (crystal meth), and 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy) represent the most frequently abused amphetamine-type stimulants (ATS). Differences in pharmacological potency and metabolism have been shown for the enantiomers of all three stimulants. Legal consequences in cases of drug possession may also differ according to the German law depending on the enantiomeric composition of the seized drug. Therefore, enantioselective monitoring of seized specimens is crucial for legal and forensic casework. Various kinds of samples of amphetamine (n = 143), MDMA (n = 94), and methamphetamine (n = 528) that were seized in southern Germany in 2019 and…
Montmorillonite nanodevices for the colon metronidazole delivery.
2013
The adsorption profiles of the antibiotic metronidazole (MNE) into the K10-montmorillonite (MMT-K10) clay and the subsequent release have been investigated as a function of pH and MNE/MMT-K10 ratio, in order to evaluate the potential of the MNE/MMT-K10 hybrids as controlled drug delivery system. The adsorption mechanism has been first elucidated by performing complementary equilibrium and kinetic studies and through the X-ray diffractometry (XRD) characterization of the obtained composite materials. The gathered results allowed us to propose a mechanism consisting of a multi-step pathway involving the neutral and the cationic form of the drug, which interact with different sites of the clay…
Automated analysis of quetiapine and other antipsychotic drugs in human blood by high performance-liquid chromatography with column-switching and spe…
2004
Abstract An automated HPLC method with column switching is described for the determination of quetiapine, clozapine, perazine, olanzapine and metabolites in blood serum. After clean-up on silica C8 material (20 μm particle size) drugs were separated on ODS Hypersil C18 material (5 μm; column size 250 mm × 4.6 mm i.d.) within 25 min and quantified by ultraviolet (UV) detection at 254 nm. The limit of quantification ranged between 10 and 50 ng/ml. At therapeutic concentrations of the drugs, the inter-assay reproducibility was below 10%. Analyses of drug concentrations in serum of 75–295 patients treated with therapeutic doses of the antipsychotic drugs revealed mean ± S.D. steady state concen…
A Colorimetric Membrane-Based Sensor with Improved Selectivity towards Amphetamine
2021
Due to their simplicity, speed and low cost, chemical spot tests are increasingly demanded for the presumptive identification of illicit drugs in a variety of contexts such as point-of-care assistance or prosecution of drug trafficking. However, most of the colorimetric reactions used in these tests are, at best, drug class selective. Therefore, the development of tests based on chemical reactions with improved discrimination power is of great interest. In this work, we propose a new colorimetric assay for amphetamine (AMP) based on its reaction with solutions of alkaline gold bromide to form an insoluble yellow–orange derivative. The resulting suspensions are then filtered onto nylon membr…
Core-crosslinked polymeric micelles: Principles, preparation, biomedical applications and clinical translation
2015
Polymeric micelles (PM) are extensively used to improve the delivery of hydrophobic drugs. Many different PM have been designed and evaluated over the years, and some of them have steadily progressed through clinical trials. Increasing evidence suggests, however, that for prolonged circulation times and for efficient EPR-mediated drug targeting to tumors and to sites of inflammation, PM need to be stabilized, to prevent premature disintegration. Core-crosslinking is among the most popular methods to improve the in vivo stability of PM, and a number of core-crosslinked polymeric micelles (CCPM) have demonstrated promising efficacy in animal models. The latter is particularly true for CCPM in…