Search results for "Drugs"
showing 10 items of 747 documents
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…
Common Neural Mechanisms of Palatable Food Intake and Drug Abuse: Knowledge Obtained with Animal Models
2019
Eating is necessary for survival, but it is also one of the great pleasures enjoyed by human beings. Research to date shows that palatable food can be rewarding in a similar way to drugs of abuse, indicating considerable comorbidity between eating disorders and substance-use disorders. Analysis of the common characteristics of both types of disorder has led to a new wave of studies proposing a Gateway Theory of food as a vulnerability factor that modulates the development of drug addiction. The homeostatic and hedonic mechanisms of feeding overlap with some of the mechanisms implicated in drug abuse and their interaction plays a crucial role in the development of drug addiction. Studies in…
Preliminary Practical Findings on Drug Monitoring by a Transcutaneous Collection Device
1996
A noninvasive and nonocclusive skin patch (Sudormed™) was investigated for the systematic collection of drugs of abuse over a period of several days. First, the applicability and user friendliness were tested by volunteers. The permeability of the polyurethane dressing from the outside to the inside for an aqueous solution was shown by incubating the outside layer with Rhodamine B. No fluorescence could be detected in the cotton pad beneath. A single dose experiment using theophylline as a model compound showed that there was a delay in time before the substance could be determined in the pad. The drug content decreased with increasing time of patch application. When eight volunteers partic…
Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Enalapril
2018
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence testing for the marketing authorization of immediate-release, solid oral dosage forms containing enalapril maleate are reviewed. Enalapril, a prodrug, is hydrolyzed by carboxylesterases to the active angiotensin-converting enzyme inhibitor enalaprilat. Enalapril as the maleate salt is shown to be highly soluble, but only 60%-70% of an orally administered dose of enalapril is absorbed from the gastrointestinal tract into the enterocytes. Consequently, enalapril maleate is a Biopharmaceutics Classification System class III substance. Because in situ conversion of the maleate salt to the sodium salt is sometim…
Potential transbuccal delivery of l-DOPA methylester prodrug: stability in the environment of the oral cavity and ability to cross the mucosal tissue
2016
Levodopa (l-DOPA) is the most effective pharmacologic agent in Parkinson's disease and remains the "gold standard". Nevertheless, in long-term treatments, dyskinesias and motor complications can emerge. In this work, the combined use of l-DOPA methylester hydrochloride prodrug (LDME) with transbuccal drug delivery was supposed as a good alternative method to optimize the bioavailability of l-DOPA, to maintain constant plasma levels and to decrease the drug unwanted effects. The effects of environmental pH on buccal delivery of LDME were evaluated ex vivo. The increase of pH value from 5.8 to 6.2 implies an improvement of drug permeation. Since the pH increase causes the raising of hydrolyti…
The zebrafish embryo as an in vivo model for screening nanoparticle-formulated lipophilic anti-tuberculosis compounds.
2021
ABSTRACT With the increasing emergence of drug-resistant Mycobacterium tuberculosis strains, new and effective antibiotics against tuberculosis (TB) are urgently needed. However, the high frequency of poorly water-soluble compounds among hits in high-throughput drug screening campaigns is a major obstacle in drug discovery. Moreover, in vivo testing using conventional animal TB models, such as mice, is time consuming and costly, and represents a major bottleneck in lead compound discovery and development. Here, we report the use of the zebrafish embryo TB model for evaluating the in vivo toxicity and efficacy of five poorly water-soluble nitronaphthofuran derivatives, which were recently id…
Gender difference in drug use in hospitalized elderly patients.
2015
Purpose The aims of this study were to evaluate whether or not there are gender differences in drug use at hospital admission and prescription at discharge and to evaluate the effect of hospitalization on medication patterns in the elderly. Method In-patients aged > 65 years included in the REPOSI registry during a recruitment period of 3 years (2008-2010-2012) were analyzed in order to evaluate drug use at hospital admission and prescription at discharge according to gender. Results A total of 3473 patients, 52% women and 48% men, were considered. Polypharmacy (> 5 drugs) is more frequent in men both at hospital admission and discharge. At hospital discharge, the number of prescripti…
Effects of Some Directly-Acting Smooth Muscle Relaxant Drugs on Isolated Human Preparations of the Upper Urinary Tract
1985
It is generally assumed that drugs which induce relaxation of smooth muscles may be of clinical importance in some urological disorders; such drugs are indeed widely used, for example in the therapy of unstable bladders or to facilitate the passage of ureteral stones. Antispasmodic action may be classified in neurotropic and musculo-tropic action; the former acting on the autonomic nervous system and the latter directly on smooth muscle cells. Examples for the first type of action are anticholinergic drugs or alpha-adrenoceptor-antagonists, whereas papaverine is a classic drug with the second type of action.
Selected cytotoxic gold compounds cause significant inhibition of 20S proteasome catalytic activities
2014
Abstract Six structurally diverse cytotoxic gold compounds are reported to cause profound and differential inhibition of the three main catalytic activities of purified 20S proteasome whilst auranofin , an established gold(I) drug in clinical use, is nearly ineffective. In particular, the gold(I) complex [( pbiH ) Au ( PPh 3 )] PF 6 , turns out to be the most potent inhibitor of all three enzyme activities with sub-micromolar IC 50 values. The present results further support the view that proteasome inhibition may play a major – yet not exclusive – role in the cytotoxic actions of gold based anticancer agents.
Perspiration versus saliva--basic aspects concerning their use in roadside drug testing.
1999
Various aspects concerning the practical application and forensic interpretation of data obtained by saliva drug testing and drug monitoring from the skin surface are discussed. Basic information on the composition of saliva and skin secretions and their particular transport mechanisms, as far as known, are given. For drugs of abuse secretion into saliva is suggested to be by passive diffusion and to depend on lipid solubility, pKa, plasma protein binding and on the pH of saliva. Drug molecules from blood are considered to reach the skin surface by various routes such as by sweat and sebum as well as by inter- and/or transcellular diffusion. The role of the stratum corneum as a temporary dr…