Search results for "Kinetic"
showing 10 items of 3064 documents
Concentrations of 9-Tetrahydrocannabinol and 11-Nor-9-Carboxytetrahydrocannabinol in Blood and Urine After Passive Exposure to Cannabis Smoke in a C…
2010
Cannabinoid concentrations in blood and urine after passive exposure to cannabis smoke under real-life conditions were investigated in this study. Eight healthy volunteers were exposed to cannabis smoke for 3 h in a well-attended coffee shop in Maastricht, Netherlands. An initial blood and urine sample was taken from each volunteer before exposure. Blood samples were taken 1.5, 3.5, 6, and 14 h after start of initial exposure, and urine samples were taken after 3.5, 6, 14, 36, 60, and 84 h. The samples were subjected to immunoassay screening for cannabinoids and analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol (THC), 11-nor-hydroxy-Delta(9)-tetra…
Alteration of vancomycin pharmacokinetics during cardiopulmonary bypass in patients undergoing cardiac surgery.
2003
The alteration of vancomycin pharmacokinetics during cardiopulmonary bypass (CPB) in patients undergoing cardiac surgery was studied. Eighteen patients were enrolled in the study. Vancomycin (1 g) was intravenously infused one to two hours before surgery. Blood samples were taken before, during, and after CPB. Serum drug concentrations were determined by an automated fluorescence polarization immunoassay and adjusted, with a bayesian analysis, to a bi-compartmental model implemented in a pharmacokinetic system program. Serum creatinine, hematocrit, and plasma proteins were also measured before, during, and after CPB. During CPB, serum creatinine, hematocrit, and plasma protein values all de…
Do Stretch Durations Affect Muscle Mechanical and Neurophysiological Properties?
2016
International audience; The aim of the study was to determine whether stretching durations influence acute changes of mechanical and neurophysiological properties of plantar flexor muscles. Plantar flexors of 10 active males were stretched in passive conditions on an isokinetic dynamometer. Different durations of static stretching were tested in 5 randomly ordered experimental trials (1, 2, 3, 4 and 10×30-s). Fascicle stiffness index, evoked contractile properties and spinal excitability (Hmax/Mmax) were examined before (PRE), immediately after (POST0) and 5 min after (POST5) stretching. No stretch duration effect was recorded for any variable. Moreover, whatever the stretching duration, st…
Opioid Plasma Concentrations during a Switch from Transdermal Fentanyl to Methadone
2007
Opioid switching is often used to improve the opioid response in patients with cancer experiencing poor analgesia or adverse effects. When switching between drugs with delayed effect because of pharmacokinetics or type of delivery, concerns exist about the correct timing of introducing the second drug after stopping the previous one. The aim of this study was to assess plasmatic changes of fentanyl and methadone underlying the clinical events occurring during opioid switching. Eighteen patients with cancer receiving transdermal fentanyl with uncontrolled pain and/or moderate to severe opioid adverse effects, were switched to oral methadone using an initial fixed ratio of 1:20. Fentanyl patc…
Precision and Bias of Target-Controlled Prolonged Propofol Infusion for General Anesthesia and Sedation in Neurosurgical Patients
2018
The aim of this study was to determine the relationship, precision, and bias of a propofol target-controlled infusion (TCI) system during prolonged infusion in neurosurgical patients. We retrospectively included patients undergoing general anesthesia for elective neurosurgical removal of brain tumors and postoperative sedation in the intensive care unit over a period of 3 months. TCI of propofol (Diprifusor - Marsh model) and remifentanil were used for general anesthesia and sedation. We compared propofol blood concentration (Cmeas) measured by liquid chromatography-mass spectroscopy with predicted concentrations (Cpred) by the TCI system at 40 minutes (T0), 2 hours (T1), and 4 hours (T2) a…
1 Hz rTMS enhances extrastriate cortex activity in migraine
2003
We recently reported a paradoxical facilitatory effect of 1 Hz repetitive TMS (rTMS) on the primary visual cortex in migraine possibly due to the failure of inhibitory circuits, unable to be upregulated by low frequency rTMS. To investigate if inhibitory circuit dysfunction extends beyond striate cortex in migraine with aura, we studied the effects of 1 Hz rTMS over the right extrastriate cortex on perception of illusory contours in these patients. Low-frequency rTMS enhanced activity of extrastriate cortex in migraineurs, speeding up reaction times on illusory contour perception. This finding supports the view of a failure of inhibitory circuits also involving the extrastriate cortex in mi…
Study of pituitary secretion in relation to retinopathy in patients with juvenile diabetes mellitus.
1981
Fifteen juvenile diabetic patients with normal eye fundus, 6 with non proliferative retinopathy, 5 with proliferative retinopathy and 5 healthy control subjects were studied in order to investigate pituitary function in relation to diabetic retinopathy. ACTH values at 08(00) and 18(00), hPRL and TSh secretion in response to 200 microgram TRH i.v., and GH secretion in response to 500 mg oral L-dopa were evaluated. In all diabetic subjects, 08(00) ACTH levels were lower than in controls. Basal hPRL, TSH and GH values of the diabetics did not differ from those of the controls. No significant differences were found in hPRL levels in response to TRH, whereas significantly lower TSH responses wer…
Plasma levels of benperidol, prolactin, and homovanillic acid after intravenous versus two different kinds of oral application of the neuroleptic in …
2009
Plasma levels of prolactin (PRL) and the butyrophenone neuroleptic benperidol (BPD) were closely followed 0 to 48 h after acute application of 6 mg BPD as intravenous injection, orally as liquid, and orally as tablets in 12 schizophrenic patients using a partially randomized cross over design. Drug concentrations showed application specific pharmacokinetic behavior with complete elimination within 48 h. All three applications led to a biphasic PRL response with pronounced initial plasma PRL peaks returning to baseline levels within 48 h. The results suggest that after acute neuroleptic challenge BPD plasma levels as low as 2-3 ng/ml can be sufficient for complete depletion of pituitary PRL …
Effects of corticotropin-releasing hormone on respiratory parameters during sleep in normal men.
2009
Corticotropin-releasing hormone (CRH) is well-known to be a centrally acting respiratory stimulant after systemic application both in healthy subjects and in patients suffering from respiratory failure. In order to study the effects of CRH on sleep EEG and respiratory parameters during sleep, 14 healthy male volunteers were investigated in a single-blind placebo controlled design. After an adaptation night, polysomnography was performed during two successive nights between 23.00 hrs. and 7.00 hrs. During one night placebo was applied, on the other 50 μg ovine CRH was administered intravenously as a bolus every hour from 0.00 hrs. to 6.00 hrs. For the assessment of respiration, blood oxygen …
High-dose short-term administration of naringin did not alter talinolol pharmacokinetics in humans.
2015
Naringin is considered the major causative ingredient of the inhibition of intestinal drug uptake by grapefruit juice. Moreover, it is contained in highly dosed nutraceuticals available on the market. A controlled, open, randomized, crossover study was performed in 10 healthy volunteers to investigate the effect of high-dose naringin on the bioavailability of talinolol, a substrate of intestinal organic anion-transporting polypeptide (OATP)-mediated uptake. Following 6-day supplementation with 3 capsules of 350 mg naringin daily, 100mg talinolol were administered orally with 3 capsules of the same dietary supplement (1050 mg naringin) on the seventh day. This test treatment was compared to …