Search results for "Kinetic"
showing 10 items of 3064 documents
Histamine up-regulates phosphodiesterase 4 activity and reduces prostaglandin E2-inhibitory effects in human neutrophils.
2000
Objective: To investigate whether histamine produces up-regulation of phosphodiesterase (PDE) activity with functional consequences in human peripheral blood neutrophils.¶Methods: PDE activity was studied by a radioisotopic method following anion-exchange chromatography. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of mRNA transcripts of PDE4 subtypes. Cyclic AMP (cAMP) levels were measured by enzyme-immunoassay, and superoxide generation by cytochrome c reduction.¶Treatment: Neutrophils were incubated for 4 h with histamine (1 μM).¶Results: PDE4 was the only isoenzyme activity increased in treated neutrophils. Kinetic analysis showed a ∼1.5-fold increase …
External evaluation of population pharmacokinetic models of vancomycin in neonates: the transferability of published models to different clinical set…
2013
Vancomycin is one of the most evaluated antibiotics in neonates using modeling and simulation approaches. However no clear consensus on optimal dosing has been achieved. The objective of the present study was to perform an external evaluation of published models, in order to test their predictive performances in an independent dataset and to identify the possible study-related factors influencing the transferability of pharmacokinetic models to different clinical settings. Published neonatal vancomycin pharmacokinetic models were screened from the literature. The predictive performance of 6 models was evaluated using an independent dataset (112 concentrations from 78 neonates). The evaluati…
In vivo metabolism of LDL subfractions in patients with heterozygous FH on statin therapy
2004
LDL can be subfractionated into buoyant (1.020-1.029 g/ml(-1)), intermediate (1.030-1.040 g/ml(-1)), and dense (1.041-1.066 g/ml(-1)) LDLs. We studied the rebound of these LDL-subfractions after LDL apheresis in seven patients with heterozygous familial hypercholesterolemia (FH) regularly treated by apheresis (58 +/- 9 years, LDL-cholesterol = 342 +/- 87 mg/dl(-1), triglycerides = 109 +/- 39 mg/dl(-1)) and high-dose statins. Apolipoprotein B (apoB) concentrations were measured in LDL subfractions immediately after and on days 1, 2, 3, 5, and 7 after apheresis. Compartmental models were developed to test three hypotheses: 1) that dense LDLs are derived from the delipidation of buoyant and in…
Clinical and Epidemiological Study on Patients with Mandibular Fractures within the Oral and Maxillofacial Surgery Compartment in the Sibiu County Cl…
2019
Abstract Traumatology from the oral and maxillofacial area represents a very important and frequent pathology within this specialty, the mandibular fractures occupying the first place in terms of location and frequency due to the anatomical prominent position of the mandible. The first three etiological factors are represented by aggressions, accidental falls and car accidents. This article, accomplished in collaboration with the statistical service of the Sibiu County Clinical Emergency Hospital, aims at analysing the distribution by sex, origin environments, levels of studies, presentation of patients, analysis which was broken down by days of the week, frequent symptoms of these types of…
Single Intravenous Dose Kinetics and Accumulation of Atenolol in Patients with Impaired Renal Function and on Hemodialysis
1980
The concentration of atenolol in plasma and urine was determined following an intravenous (i.v.) dose given to 17 hypertensive patients with a glomerular filtration rate (GFR) between 5 and 105 ml/min and in 4 patients on hemodialysis. In patients with normal renal function the mean half life of elimination was calculated to be 6.8 h. This value increased to a mean of 50.1 h in patients with a GFR below 10 ml/min. In patients on hemodialysis the half life of elimination was about 4 h. The elimination rate constants as well as the body and renal clearances of atenolol have a significant correlation with the GFR. Although accumulation of atenolol was observed, especially after multiple oral d…
Specific, concentration-dependent uptake of vitellin by the oocytes ofNereis virens (Annelida, Polychaeta) in vitro
1991
One purpose of this study was the development of methods for radioactive labeling and handling of the yolk protein of Nereis virens, another, the utilization of this tracer in nereid oocyte cultures to describe the kinetics and specificity of yolk protein uptake. Accumulation of labeled yolk protein by growing oocytes is linear over time, specific for yolk protein, and dependent on tracer concentration in the medium. Incorporation of yolk protein follows saturation kinetics which allows us to reproducibly determine the characteristics of this process. The apparent KM of ∼ 1 × 10−8 M indicates the high affinity of the transport system; the Vmax (160–400 pg protein/day × oocyte) reveals that …
Effects of rectilinear acceleration and optokinetic and caloric stimulations in space.
1984
During the flight of Spacelab 1 the crew performed a number of experiments to explore changes in vestibular function and visual-vestibular interactions on exposure to microgravity. Measurements were made on the threshold for detection of linear oscillation, vestibulo-ocular reflexes elicited by angular and linear movements, oculomotor and posture responses to optokinetic stimulations, and responses to caloric stimulation. Tests were also conducted on the ground, during the 4 months before and on days 1 to 6 after flight. The most significant result was that caloric mystagmus of the same direction as on the earth could also be evoked in the weightless environment.
Electronystagmography in the diagnosis of central vertigo.
2011
Objective: Determine the efficacy and applicability of electronystagmography (ENG) testing in the differential diagnosis between peripheral and central vertigo, through the visual-vestibular interaction test, in patients with vertigo.Method: Patients were submitted to ENG recording. Patients sat on a rotatory chair, which was placed in the middle of a rotary rotatory cylindrical chamber. The rotatory chamber was driven by a direct current engine, which turned it clockwise and counterclockwise, and its internal area was covered with 32 black vertical contrast.Results: All patients underwent rotatory vestibular stimulation by Stop test (VOR), optokinetic stimulation (OKN), and contemporary ro…
Muscle conduction velocity, strength, neural activity, and morphological changes after eccentric and concentric training
2014
This study compared the effects of concentric and eccentric training on neuromuscular adaptations in young subjects. Twenty-two men and women were assigned to one of two groups: concentric (CON, n = 11) and eccentric (ECC, n = 11) training. Training consisted of 6 weeks of isokinetic exercise, performed twice weekly, starting with two sets of eight repetitions, and progressing to five sets of 10 repetitions. Subjects were tested in strength variables [concentric, eccentric, and isometric peak torque (PT), and rate of force development (RFD)], muscle conduction velocity (CV), neuromuscular activity, vastus lateralis (VL) muscle thickness, and echo intensity as determined by ultrasonography. …
INT-009 Pharmacokinetics of linezolid and meropenem in intensive care unit patients receiving continuous renal replacement therapy
2016
Background Intensive care unit (ICU) patients often suffer from infections and acute renal failure and might need continuous renal replacement therapy commonly applied by veno-venous hemodialysis (CVVHD) or hemodiafiltration (CVVHDF). In this case there are no dosage recommendations in the product informations of antibiotics and literature data are scarce. The risk for therapy failure, development of resistance and adverse drug effects is elevated. Purpose Aim of the presented study was to find out if standard therapy of Linezolid (LZ) and Meropenem (MP) results in adequate plasma levels in surgical ICU patients receiving CVVHD(F). Materials and Methods Surgical ICU patients receiving CVVHD…