Lovastatin decreases de novo cholesterol synthesis and LDL Apo B-100 production rates in combined-hyperlipidemic males

The effect of lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity, on the kinetics of de novo cholesterol synthesis and apolipoprotein (apo) B in very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and low-density lipoprotein (LDL) was investigated in five male patients with combined hyperlipidemia. Subjects were counseled to follow a Step 2 diet and were treated with lovastatin and placebo in randomly assigned order for 6-week periods. At the end of each experimental period, subjects were given deuterium oxide orally and de novo cholesterol synthesis was assessed from deuterium incorporation into cholesterol and expressed as fractional synthesis rate (C-FSR) and production rate (C-PR). Simultaneously, the kinetics of VLDL, IDL, and LDL apo B-100 were studied in the fed state using a primed-constant infusion of deuterated leucine to measure fractional catabolic rates (FCR) and production rates (PR). Drug treatment resulted in significant decreases in total cholesterol (-29%), VLDL cholesterol (-40%), LDL cholesterol (-27%), and apo B (-16%) levels and increases in HDL cholesterol (+13%) and apolipoprotein (apo) A-I (+11%) levels. Associated with these plasma lipoprotein responses was a significant reduction in both de novo C-FSR (-40%; P = .04) and C-PR (-42%; P = .03). Treatment with lovastain in these patients had no significant effect on the FCR of apoB-100 in VLDL, IDL, or LDL, but resulted in a significant decrease in the PR of apoB-100 in IDL and LDL. Comparing the kinetic data of these patients with those of 10 normolipidemic control subjects indicates that lovastatin treatment normalized apoB-100 IDL and LDL PR. The results of these studies suggest that the declines in plasma lipid levels observed after treatment of combined hyperlipidemic patients with lovastatin are attributable to reductions in the C-FSR and C-PR of de novo cholesterol synthesis and the PR of apoB-100 containing lipoproteins. The decline in de novo cholesterol synthesis, rather than an increase in direct uptake of VLDL and IDL, may have contributed to the decline in the PR observed.     

3D reconstruction of tomographic images applied to largely spaced slices

This paper presents a full reconstruction process of magnetic resonance images. The first step is to bring the acquired data from the frequency domain, using a Fast Fourier Transform algorithm. A Tomographic Image Interpolation is then used to transform a sequence of tomographic slices in an isotropic volume data set, a process also called 3D Reconstruction. This work describes an automatic method whose interpolation stage is based on a previous matching stage using Delaunay Triangulation. The reconstruction approach uses an extrapolation procedure that permits appropriate treatment of the boundaries of the object under analysis.     

Quantitative assessment of the motion of the lumbar spine in the low back pain population and the effect of different spinal pathologies of this motion

There are few objective means by which disability caused by low back pain (LBP) can be quantified. The purpose of this study was to investigate the usefulness of motion measurements in the assessment of LBP. The motion characteristics of 138 LBP subjects were investigated, and the data compared with a previously published database of normal subjects. Values of range of motion and angular velocity were obtained for all subjects in each plane of motion. Analysis of these motion characteristics demonstrated significant differences (P < 0.0001) between the two populations; however both populations demonstrated considerable intersubject variation. Multiple regression analysis revealed that some of the variance in the LBP population was attributable to the underlying diagnosis. Patients with a spondylolisthesis tended to be hypermobile whilst those with spinal stenosis, disc prolapse or degenerative disc disease tended to be hypomobile. All diagnostic groups showed impairments in their velocity characteristics.     

Caffeine self-administration in humans: 1. Efficacy of cola vehicle

Eight exclusive cola drinkers in Experiment 1 (mean caffeine intake = 157 +/- 74 mg/day) and 16 drinkers of both cola and coffee in Experiment 2 (mean caffeine intake = 579 +/- 201 mg/day) underwent 6 independent, double-blind weekly trials. Each trial began with a randomized cross-over sampling period of 1 day of access to noncaffeinated cola and 1 day of access to caffeinated (33 mg/8 oz) cola. During the subsequent 1- or 2-day test period, participants had unlimited concurrent access to the 2 colas. Reliable caffeine self-administration occurred in 2 of 8 participants in Experiment 1 and in 4 of 16 participants in Experiment 2. Self-reported drowsiness, fatigue, and headache were higher when participants received only placebo colas in Experiment 2, but not Experiment 1. Caffeine self-administration via cola occurs both among people whose primary source of caffeine is cola and among those whose primary source of caffeine is coffee.