Search results for "Kinetic"
showing 10 items of 3064 documents
Clearance and metabolism of arachidonic acid by C6 glioma cells and astrocytes.
1995
Effects of increased levels of arachidonic acid (AA) were analyzed in vitro by employment of C6 glioma cells and astrocytes from primary culture. The cells were suspended in a physiological medium added with arachidonic acid (AA) in a concentration range from 0.01 to 0.5 mM. The concentration profiles of the fatty acid and AA-metabolites were subsequently followed for 90 min. AA was measured by gas chromatography, whereas the AA-metabolites PGF2 alpha and LTB4 by radioimmunoassay (RIA). Following administration of AA at 0.05 or 0.1 mM the medium was completely cleared from the fatty acid within 10 to 15 min. However, when 0.5 mM were added, AA concentrations of 0.36 +/- 0.055 mM were found …
Parathyroid hormone serum concentration kinetic profile in critically ill patients undergoing continuous renal replacement therapies: a prospective o…
2021
Introduction: Elevated serum parathormone (PTH) levels have been observed in acute kidney injury and are related to calcium-phosphate metabolism disturbance, decreased renal production of 1,25 dihydroxyvitamin D3, impaired renal PTH excretion, and other renal-independent factors. There are no data regarding PTH concentration kinetics in critically ill patients undergoing continuous renal replacement therapies (CRRT) in an intensive care setting. The primary objective of this study was to investigate trends in PTH serum levels in critically ill patients with multiorgan failure undergoing CRRT, by performing periodic PTH measurements in the acute phase of critical illness. Material and method…
Concentric and/or Eccentric Training-Induced Alterations in Shoulder Flexor and Extensor Strength
1997
To examine the effect of specific concentric and eccentric training on muscular strength following an initial standardized period of excessive training, shoulder extensors and flexors were tested. The shoulder is a joint particularly susceptible to injury and requires a specific strength training program. For a period of 12 weeks, subjects performed training, including concentric and eccentric actions. Thereafter, they were divided into three groups that performed specific 12-week programs, including either concentric (C-E/C), eccentric (C-E/E), or a combination of both concentric and eccentric exercises (C-E/C-E). Following the initial period of training, significant increases (p0.05) in p…
Effect of aging on pain relief in the older cancer patients: pharmacokinetic and pharmacodynamic aspects.
2016
The prevalence of cancer rises with advancing age. A large number of cancer patients are aged over 65 years, and it is expected that even more patients will develop cancer as a consequence of the g...
Serum Levels of Sulpiride Enantiomers after Oral Treatment with Racemic Sulpiride in Psychiatric Patients: a Pilot Study1
2001
Sulpiride (SULP), a substituted benzamide with high selectivity for D 2 -like dopamine receptors, has a chiral structure and is used in most countries as the racemate. In an open pilot study, we investigated 26 inpatients (13 female, 13 male) with schizophrenic or depressive disorder treated with SULP (mean daily dosage 64-1062 mg) administered orally, either as a monotherapy or as an add-on treatment to a stable and unchanged medication for 3-60 days. Serum levels of total SULP and of its enantiomers were measured by high-performance liquid chromatography (HPLC) procedures. Clinically relevant indicators of hepatic and renal function as well as retrospectively assessed clinical outcome par…
The lipoprotein lipase activity in cultured beating heart cells of the post-natal rat.
1974
Summary The lipoprotein lipase (LPL) activity was studied in cultured beating heart cells of the post natal rat as a function of the culture age, from the freshly trypsinized cell suspension up to the 14th day of culture. The LPL activity remains at a practically stationary level during the first four days of culture, and then increases rapidly to reach a plateau, at a level 3–4 times higher at the 21th day of culturing. The significance of this enzymatic activity progression comparing to 3H thymidine incorporation from the point of view of cell differentiation is discussed. Our results suggest that after the 12th day of culture, cells contain their optimal enzymatic apparatus for lipid met…
Identification of α2-adrenoceptors and non-adrenergic idazoxan binding sites in rabbit colon epithelial cells
1990
alpha 2-Adrenoceptors are possibly involved in the regulation of the hydroelectrolytic flux across the digestive mucosa. As no data are available concerning the existence of these receptors in colon epithelial cells, we aimed to investigate the existence of alpha 2-adrenoceptors in this tissue using tritiated antagonists. [3H]Yohimbine and [3H]rauwolscine were not usable to label colonic alpha 2-adrenoceptors because of their very high level of non-specific binding. In contrast, the methoxy derivative of idazoxan, [3H]RX821002, appeared a convenient radioligand for the purpose. [3H]RX821002 bound with high affinity (KD = 6.2 +/- 0.8 nM) to a single population of non-interacting sites (Bmax …
Clinical management of drug-drug interactions in HCV therapy: Challenges and solutions.
2013
Contains fulltext : 118153.pdf (Publisher’s version ) (Open Access) Hepatitis C virus (HCV) infected patients often take multiple co-medications to treat adverse events related to HCV therapy, or to manage other co-morbidities. Drug-drug interactions associated with this polypharmacy are relatively new to the field of HCV pharmacotherapy. With the advent of the direct-acting antivirals telaprevir and boceprevir, which are both substrates and inhibitors of the cytochrome P450 (CYP) 3A iso-enzyme, knowledge and awareness of drug-drug interactions have become a cornerstone in the evaluation of patients starting and continuing HCV combination therapy. In our opinion, an overview of conducted dr…
Relaxation by Calcium Antagonists of Potassium-contracted Trachea from Normal and Sensitized Guinea-pigs: Influence of Epithelium and the Surface of …
1993
Abstract A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings, isolated from normal (unsensitized) or sensitized guinea-pigs, was used to study the role of the epithelium in the relaxation produced by calcium antagonists (verapamil, nifedipine, cinnarizine and flunarizine) of K+-induced contraction. In trachea from normal guinea-pigs, the relaxation to verapamil for unrestricted or mucosal drug entry was reduced in the absence of epithelium, whereas the relaxation produced by nifedipine, cinnarizine or flunarizine was unchanged. In sensitized trachea, the relaxation elicited by the calcium antagonists tested was similar in intact…
Different muscarine receptors mediate the prejunctional inhibition of [3H]-noradrenaline release in rat or guinea-pig iris and the contraction of the…
1989
To investigate the muscarine receptor type mediating inhibition of [3H]-noradrenaline release from the isolated rat and guinea-pig iris we have determined the potency of antimuscarinic drugs to antagonize the methacholine-induced inhibition of [3H]-noradrenaline overflow evoked by field stimulation (3 Hz, 2 min). The prejunctional apparent affinities were compared with those obtained for postjunctional muscarine receptors mediating the methacholine-induced contraction of the isolated rabbit iris sphincter muscle. Prejunctional apparent affinity constants of pirenzepine (6.67), himbacine (8.51), methoctramine (7.92), 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, 8.00), hexahydro-d…