|
| ||
|
|
||
Absorption Time (absorption + time)
Selected AbstractsNovel insulin analogues and its mitogenic potentialDIABETES OBESITY & METABOLISM, Issue 6 2006Ivana Zib Abstract:, Insulin analogues were developed to modify the structure of the human insulin molecule in order to more accurately approximate the endogenous secretion of insulin. With the help of recombinant technology and site-directed mutagenesis, the insulin molecule can be modified to either delay or shorten absorption time, providing better insulin treatment options and facilitating the achievement of glycaemic goals. Changing the structure of the insulin molecule, however, may significantly alter both its metabolic and mitogenic activity. Multiple factors such as residence time on the receptor, dissociation rate, rate of receptor internalization and the degree of phosphorylation of signalling proteins can affect the mitogenic potencies of insulin analogues. Changes in the structure of the insulin have raised concern about the safety of the insulin analogues. For example, questions have emerged about the relationship between the use of insulin lispro and insulin glargine and the progression of diabetic retinopathy. Two studies have shown progression of retinopathy with the use of insulin lispro. However, others have not confirmed these results, and causality could not be proven as progression of retinopathy can occur with rapid improvement in glycaemic control, and methods of assessments among studies were not consistent. Therefore, we examine the metabolic and mitogenic characteristics of the three insulin analogues, insulin lispro, insulin aspart and insulin glargine, that are currently on the market, as well as the two insulin analogues, insulin glulisine and insulin detemir, that are soon going to be available for clinical use. [source] Enhancement of heat transfer in hydrogen storage tank with hydrogen absorbing alloy (optimum fin layout)HEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 3 2008Yuichi Mitsutake Abstract Optimization of the fin layout in a metal hydride (MH) bed has been sought to enhance poor heat transmission in a hydrogen storage tank, and to obtain a maximum hydrogen absorption rate with a smaller volume of fins. Two different fin configurations, radial and circular fins, in a vertical cylindrical reactor vessel were tested with a La-Ni-based AB5 type hydrogen storage alloy. A two-dimensional transient heat conduction analysis, coupled with predicted temperature and concentration of absorbed hydrogen in the bed for the exothermic hydride reaction, was used to evaluate enhancement of the hydrogen absorption time. The estimated temperature and concentration agreed within 6 K and 8.5%, respectively, with our experimental results. The effect of thickness and the spacing and shape of fins on the hydrogen absorption time were analytically evaluated, so that the optimum range of the each fin layout was obtained by the trade off between absorption time and reduction in the MH volume due to the volume occupied by fins. The hydrogen absorption time for the recommended layout of circular fins was reduced to approximately one-third of that without fins. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(3): 165,183, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20195 [source] Comparative pharmacokinetics of amikacin in Greyhound and Beagle dogsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2008B. KUKANICH The purpose of the study was to compare the pharmacokinetics of amikacin administered i.v., to Greyhound and Beagle dogs and determine amikacin pharmacokinetics administered subcutaneously to Greyhounds. Amikacin was administered i.v. at 10 mg/kg to six healthy Greyhounds and six healthy Beagles. The Greyhounds also received amikacin, 10 mg/kg s.c. Plasma was sampled at predetermined time points and amikacin concentrations determined by a fluorescence polarization immunoassay (FPIA). The volume of distribution was significantly smaller in Greyhounds (mean = 176.5 mL/kg) compared to Beagles (234.0 mL/kg). The C0 and AUC were significantly larger in Greyhounds (86.03 ,g/mL and 79.97 h·,g/mL) compared to Beagles (69.97 ,g/mL and 50.04 h·,g/mL). The plasma clearance was significantly lower in Greyhounds (2.08 mL/min/kg) compared to Beagles (3.33 mL/min/kg). The fraction of the dose absorbed after s.c. administration to Greyhounds was 0.91, the mean absorption time was 0.87 h, and the mean maximum plasma concentration was 27.40 ,g/mL at 0.64 h. Significant differences in the pharmacokinetics of amikacin in Greyhounds indicate it should be administered at a lower dose compared to Beagles. The dose in Greyhounds to achieve a Cmax:AUC , 8 for bacteria (with an MIC , 4 ,g/mL) is 12 mg/kg q24 h compared to 22 mg/kg q24 in Beagles. [source] Pharmacokinetics of sarafloxacin in pigs and broilers following intravenous, intramuscular, and oral single-dose applicationsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2001H. Z. Ding Pharmacokinetics of sarafloxacin, a fluoroquinolone antibiotic, was determined in pigs and broilers after intravenous (i.v.), intramuscular (i.m.), or oral (p.o.) administration at a single dose of 5 (pigs) or 10 mg/kg (broilers). Plasma concentration profiles were analysed by a noncompartmental pharmacokinetic method. Following i.v., i.m. and p.o. doses, the elimination half-lives (t1/2,) were 3.37 ± 0.46, 4.66 ± 1.34, 7.20 ± 1.92 (pigs) and 2.53 ± 0.82, 6.81 ± 2.04, 3.89 ± 1.19 h (broilers), respectively. After i.m. and p.o. doses, bioavailabilities (F) were 81.8 ± 9.8 and 42.6 ± 8.2% (pigs) and 72.1 ± 8.1 and 59.6 ± 13.8% (broilers), respectively. Steady-state distribution volumes (Vd(ss)) of 1.92 ± 0.27 and 3.40 ± 1.26 L/kg and total body clearances (ClB) of 0.51 ± 0.03 and 1.20 ± 0.20 L/kg/h were determined in pigs and broilers, respectively. Areas under the curve (AUC), mean residence times (MRT), and mean absorption times (MAT) were also determined. Sarafloxacin was demonstrated to be more rapidly absorbed, more extensively distributed, and more quickly eliminated in broilers than in pigs. Based on the single-dose pharmacokinetic parameters determined, multiple dosage regimens were recommended as: a dosage of 10 mg/kg given intramuscularly every 12 h in pigs, or administered orally every 8 h in broilers, can maintain effective plasma concentrations with bacteria infections, in which MIC90 are <0.25 ,g/mL. [source] | ||||||||||