Search results for "45"
showing 10 items of 1896 documents
Influence of concomitant medications on the total clearance and the risk for supra-therapeutic plasma concentrations of Citalopram. A population-base…
2014
Introduction: The main objective of this study was to investigate the influence of the use of multiple medications and other risk factors on citalopram plasma concentrations. Methods: A retrospective cohort study with a naturalistic population of 957 patients for whom routine therapeutic drug monitoring (TDM) of citalopram had been requested between 2006 and 2013 was conducted. Results: Concomitant drugs inhibiting at least 2 different CYP subtypes involved in the metabolism of citalopram decreased statistically significantly the total clearance (Clt). Compared to younger patients over 64-year-old patients had on average a 4.5 times higher risk rate of supra-therapeutic plasma concentration…
CYP3 phylogenomics: evidence for positive selection of CYP3A4 and CYP3A7.
2008
CYP3A metabolizes 50% of currently prescribed drugs and is frequently involved in clinically relevant drug interactions. The understanding of roles and regulations of the individual CYP3A genes in pharmacology and physiology is incomplete.Using genomic sequences from 16 species we investigated the evolution of CYP3 genomic loci over a period of 450 million years.CYP3A genes in amniota evolved from two ancestral CYP3A genes. Upon the emergence of eutherian mammals, one of them was lost, whereas, the other acquired a novel genomic environment owing to translocation. In primates, CYP3A underwent rapid evolutionary changes involving multiple gene duplications, deletions, pseudogenizations, and …
Hepatocytes--the choice to investigate drug metabolism and toxicity in man: in vitro variability as a reflection of in vivo.
2007
The pharmaceutical industry is committed to marketing safer drugs with fewer side effects, predictable pharmacokinetic properties and quantifiable drug-drug interactions. Drug metabolism is a major determinant of drug clearance and interindividual pharmacokinetic differences, and an indirect determinant of the clinical efficacy and toxicity of drugs. Progressive advances in the knowledge of metabolic routes and enzymes responsible for drug biotransformation have contributed to understanding the great metabolic variations existing in human beings. Phenotypic as well genotypic differences in the expression of the enzymes involved in drug metabolism are the main causes of this variability. How…
Frontiers of metal-coordinating drug design
2020
INTRODUCTION: The occurrence of metal ions in biomolecules is required to exert vital cellular functions. Metal-containing biomolecules can be modulated by small-molecule inhibitors targeting their metal-moiety. As well, the discovery of cisplatin ushered the rational discovery of metal-containing-drugs. The use of both drug types exploiting metal–ligand interactions is well established to treat distinct pathologies. Therefore, characterizing and leveraging metal-coordinating drugs is a pivotal, yet challenging, part of medicinal chemistry. AREA COVERED: Atomic-level simulations are increasingly employed to overcome the challenges met by traditional drug-discovery approaches and to compleme…
Interacciones farmacológicas de los fármacos antihipertensivos
2005
A drug interaction is the quantitative or qualitative modification of the effect of a drug by the simultaneous or successive administration of a different one. Hypertensive patients, mainly the more elderly ones, frequently present concomitant diseases that require the administration of several medicines which facilitates the appearance of interactions. The lack of effectiveness of the antihypertensive treatment is a relatively frequent fact that sometimes is due to interactions of antihypertensive drugs with other treatments. It is difficult to determine the incidence of interactions, but it is related to the number of drugs administered simultaneously. Between 37 and 60% of hospital-admis…
Drug-metabolizing enzymes in the skin of man, rat, and pig.
2007
The mammalian skin has long been considered to be poor in drug metabolism. However, many reports clearly show that most drug metabolizing enzymes also occur in the mammalian skin albeit at relatively low specific activities. This review summarizes the current state of knowledge on drug metabolizing enzymes in the skin of human, rat, and pig, the latter, because it is often taken as a model for human skin on grounds of anatomical similarities. However only little is known about drug metabolizing enzymes in pig skin. Interestingly, some cytochromes P450 (CYP) have been observed in the rat skin which are not expressed in the rat liver, such as CYP 2B12 and CYP2D4. As far as investigated most d…
Fast Regulation of Cytochrome P450 Activities by Phosphorylation and Consequences for Drug Metabolism and Toxicity
2002
In contrast to the well-known regulation of cytochrome P450 (CYP) activity by enzyme induction, which represents a process with slow onset and slow offset, more recent studies revealed phosphorylation as a fast (within observation instantaneous) and isoenzyme-selective regulation. The phosphorylated enzyme (investigated isozyme: CYP2B1) was fully inactive. The phosphorylation is mediated by PKA and hence under control of hormones and drugs that alter cellular cAMP levels. The consequences for the metabolic control of toxic species derived from drugs and environmental carcinogens are discussed. This information will help to improve therapy with drugs metabolized by CYPs which are phosphoryla…
Cell Lines: A Tool for In Vitro Drug Metabolism Studies
2008
Primary cultured hepatocytes are a valuable in vitro model for drug metabolism studies. However, their widespread use is greatly hindered by the scarcity of suitable human liver samples. Moreover, the well-known in vitro phenotypic instability of hepatocytes, the irregular availability of fresh human liver for cell harvesting purposes, and the high batch-to-batch functional variability of hepatocyte preparations obtained from different human liver donors, seriously complicate their use in routine testing. To overcome these limitations, different cell line models have been proposed for drug metabolism screening. Human liver-derived cell lines would be ideal models for this purpose given thei…
Judges, Politics and Democracy: A Discursive Analysis of the Judicial Elite during the Weimar Republic and post-WWII Germany
2014
Die personelle Kontinuität innerhalb der Justiz und der juristischen Eliten über die drei Regimewechsel hinaus, die Deutschland in der ersten Hälfte des Jahrhunderts erlebte, wurde bereits breit erforscht. Um die Entwicklung dieser Eliten in der Weimarer Republik und der frühen Nachkriegszeit zu analysieren, geht deshalb der vorliegende Beitrag nicht von den Personen, sondern von den Diskursen aus. Aus den damaligen leidenschaftlichen Debatten um die Justiz und insbesondere den Richter sticht eine zentrale, wiederkehrende Frage hervor: sollte der Übergang zur Demokratie zu einer Neubestimmung der Stellung, Funktion und Arbeit des Richters führen, und wenn ja in welchem Sinne? In der Weimare…
"Table 1" of "Study of e+ e- ---> pi+ pi- pi0 process using initial state radiation with BABAR"
2004
The measured 3PI mass spectrum calculated for a 25 MeV bin size.