Theoretical analysis of blind identification of kinetic parameters in a three compartment model: nonuniqueness problem

2003 ◽  
Author(s):  
D.Y. Riabkov ◽  
E.V.R. Di Bella
Keyword(s):  
Theoretical Analysis ◽  
Kinetic Parameters ◽  
Compartment Model ◽  
Blind Identification ◽  
Three Compartment Model

scholarly journals In Vivo Measurement of Glucose Utilization in Rats using a β-Microprobe: Direct Comparison with Autoradiography

2004 ◽  
Vol 24 (9) ◽  
pp. 1015-1024 ◽  
Author(s):  
Philippe Millet ◽  
Marcelle Moulin Sallanon ◽  
Jean-Marie Petit ◽  
Yves Charnay ◽  
Philippe Vallet ◽  
...  
Keyword(s):  
Kinetic Parameters ◽  
Animal Studies ◽  
Correlation Coefficients ◽  
Compartment Model ◽  
Input Function ◽  
In Vivo Measurement ◽  
Positron Emission ◽  
Three Compartment Model ◽  
Concentration Curves

A new β-microprobe (βP) has been used to locally measure the time–concentration curve of a radiolabeled substance. The βP, analogous to positron emission tomography methodology, is useful for in vivo animal studies because it can acquire time–concentration curves with high temporal and spatial resolution. Using [18F]fluoro-2-deoxy-d-glucose and βP, we evaluated the reliability of the biologic parameters and we compared this method with the [14C]2-deoxy-d-glucose autoradiography. βP time–concentration curves in three regions of the brain were obtained from 24 rats. Four kinetic parameters (K1-k4) were estimated from 60-minute experimental periods using a three-compartment model. Best fits were obtained when the vascular fraction (Fv) was estimated simultaneously with the four kinetic parameters (K1-k4). The mean estimated Fv values were about 5.5% for the frontal cortex regions and 8.0% for the cerebellum. Correlation coefficients higher than 0.830 were observed between regional cerebral metabolic rates for glucose (rCMRglc) values obtained by βP and autoradiography. In addition, the βP-derived input function was similar to that obtained by manual sampling. Our findings show that reliable rCMRglc values can be obtained using βP.

scholarly journals Variability in Estimated Modelled Insulin Secretion

2021 ◽  
pp. 193229682199112
Author(s):  
Jennifer J. Ormsbee ◽  
Hannah J. Burden ◽  
Jennifer L. Knopp ◽  
J. Geoffrey Chase ◽  
Rinki Murphy ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Kinetic Parameters ◽  
Pancreatic Beta Cells ◽  
Compartment Model ◽  
Interquartile Range ◽  
Cumulative Distribution ◽  
Model Framework ◽  
Intravenous Glucose ◽  
C Peptide ◽  
Model Based

Background: The ability to measure insulin secretion from pancreatic beta cells and monitor glucose-insulin physiology is vital to current health needs. C-peptide has been used successfully as a surrogate for plasma insulin concentration. Quantifying the expected variability of modelled insulin secretion will improve confidence in model estimates. Methods: Forty-three healthy adult males of Māori or Pacific peoples ancestry living in New Zealand participated in an frequently sampled, intravenous glucose tolerance test (FS-IVGTT) with an average age of 29 years and a BMI of 33 kg/m2. A 2-compartment model framework and standardized kinetic parameters were used to estimate endogenous pancreatic insulin secretion from plasma C-peptide measurements. Monte Carlo analysis (N = 10 000) was then used to independently vary parameters within ±2 standard deviations of the mean of each variable and the 5th and 95th percentiles determined the bounds of the expected range of insulin secretion. Cumulative distribution functions (CDFs) were calculated for each subject for area under the curve (AUC) total, AUC Phase 1, and AUC Phase 2. Normalizing each AUC by the participant’s median value over all N = 10 000 iterations quantifies the expected model-based variability in AUC. Results: Larger variation is found in subjects with a BMI > 30 kg/m2, where the interquartile range is 34.3% compared to subjects with a BMI ≤ 30 kg/m2 where the interquartile range is 24.7%. Conclusions: Use of C-peptide measurements using a 2-compartment model and standardized kinetic parameters, one can expect ~±15% variation in modelled insulin secretion estimates. The variation should be considered when applying this insulin secretion estimation method to clinical diagnostic thresholds and interpretation of model-based analyses such as insulin sensitivity.

Vertebral fractures and luxations in dogs and cats part 2: treatment and surgery options

2021 ◽  
Vol 26 (3) ◽  
pp. 15-19
Author(s):  
Ivona Orgonikova ◽  
Josep Brocal ◽  
Giunio Bruto Cherubini ◽  
Viktor Palus
Keyword(s):  
Spinal Cord ◽  
Vertebral Fractures ◽  
Vertebral Column ◽  
Compartment Model ◽  
Spinal Instability ◽  
Decompression Surgery ◽  
Implant Loosening ◽  
Bone Fragment ◽  
Three Compartment Model ◽  
Disc Extrusion

Assessing the presence of vertebral column instability is essential in animals with vertebral fractures or luxations. Spinal instability is most commonly assessed using a three-compartment model and unstable vertebral fractures and luxations require surgical stabilisation. In cases of compression of the spinal cord (by haematoma, traumatic intervertebral disc extrusion or bone fragment), decompression surgery is necessary. Prompt surgery prevents additional spinal cord damage, but the overall condition of the patient, including any concurrent injuries, needs to be continually kept in mind. The vertebral column can be stabilised using multiple techniques, such as screws, pins, polymethylmetacrylate and plating techniques, as well as external stabilisation and spinal stapling. Complications of spinal surgeries include haemorrhage, infection, neurological deterioration, particularly in cases of spinal stabilisations, implant loosening and failure.

Disposition Kinetics of Disopyramide in Human Healthy Volunteers Described by an Open Three Compartment Model

1989 ◽  
Vol 64 (5) ◽  
pp. 412-416 ◽  
Author(s):  
Jan Bonde ◽  
Niels Melchior Jensen ◽  
Lars E. Pedersen ◽  
Helle R. Angelo ◽  
Seren N. Rasmussen ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Compartment Model ◽  
Disposition Kinetics ◽  
Three Compartment Model ◽  
Kinetics Of

scholarly journals Purified radiolabeled antithrombin III metabolism in three families with hereditary AT III deficiency: application of a three-compartment model

Blood ◽  
1986 ◽  
Vol 67 (1) ◽  
pp. 93-98
Author(s):  
EA Knot ◽  
E de Jong ◽  
JW ten Cate ◽  
AH Iburg ◽  
CP Henny ◽  
...  
Keyword(s):  
Antithrombin Iii ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Compartment Model ◽  
Control Group ◽  
Surface Binding ◽  
Catabolic Rate ◽  
At Iii ◽  
Three Compartment Model ◽  
The Mean

Purified human radioiodinated antithrombin III (125I-AT III) was used to study its metabolism in six members from three different families with a known hereditary AT III deficiency. Six healthy volunteers served as a control group. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and crossed immunoelectrophoresis (CIE) showed the purified AT III to be homogeneous. Amino acid analysis of the protein revealed a composition identical to a highly purified internal standard. The specific activity was 5.6 U/mg. Analysis of plasma radioactivity data was performed, using a three-compartment model. Neither plasma disappearance half-times nor fractional catabolic rate constants differed significantly between patients and control subjects. The mean absolute catabolic rate in the patient group was significantly lower than that of the control group at 2.57 +/- 0.44 and 4.46 +/- 0.80 mg/kg/day, respectively. In addition, the mean patient alpha 1-phase, flux ratio (k1,2 and k2,1) of the second compartment alpha 2-phase and influx (k3,1) of the third compartment were significantly reduced as compared with control values. It has been tentatively concluded that the observed reduction in the second compartment may be caused by a decrease in endothelial cell surface binding.

scholarly journals The Concentration of Digoxin Activity after Intravenous in Three Compartments Mathematical Model

2019 ◽  
Vol 8 (2S11) ◽  
pp. 3653-3657
Keyword(s):  
Mathematical Model ◽  
Laplace Transform ◽  
Digoxin Concentration ◽  
Compartment Model ◽  
System Of Equations ◽  
Transfer Coefficients ◽  
Linear Ordinary Differential Equations ◽  
Concentration Time ◽  
The Laplace Transform ◽  
Three Compartment Model

Present paper is designed to compare the distribution of digoxin in three compartment model administered through an intravenous (i.v). These models under consideration is denoted by a system of non-linear ordinary differential equations. The Eigenvalue and the Laplace transform methods were used to solve the system of equations. Digoxin was administered to five subjects through Intravenous then, the serum digoxin concentrations were measured respectively over a period of 72 hours. The transfer coefficients were obtained from observed digoxin concentrations using method of residuals and the variation of digoxin concentration – time curves plotted using MATLAB.

A three-compartment model of the hemodynamic response and oxygen delivery to brain

NeuroImage ◽  
2005 ◽  
Vol 28 (4) ◽  
pp. 925-939 ◽  
Author(s):  
Ying Zheng ◽  
David Johnston ◽  
Jason Berwick ◽  
Danmei Chen ◽  
Steve Billings ◽  
...  
Keyword(s):  
Oxygen Delivery ◽  
Compartment Model ◽  
Hemodynamic Response ◽  
Three Compartment Model

scholarly journals Erratum to: Pharmacokinetics of digoxin: Comparison of a two- and a three-compartment model in man

1975 ◽  
Vol 3 (5) ◽  
pp. 385-385
Author(s):  
William G. Kramer ◽  
Richard P. Lewis ◽  
Tyson C. Cobb ◽  
Wilbur F. Forester ◽  
James A. Visconti ◽  
...  
Keyword(s):  
Compartment Model ◽  
Three Compartment Model
Sign in / Sign up

Export Citation Format

Share Document