Quantitative myocardial blood flow imaging with integrated time-of-flight PET-MR.

Background: The use of integrated PET-MR offers new opportunities for comprehensive assessment of cardiac morphology and function. However, little is known on the quantitative accuracy of cardiac PET imaging with integrated time-of-flight PET-MR. The aim of the present work was to validate the GE Signa PET-MR scanner for quantitative cardiac PET perfusion imaging.

Flow-mediated vasodilatation: variation and interrelationships with plasma lipids and lipoproteins.

Objective: Endothelial dysfunction is a critical, prerequisite step in atherosclerosis, and may be evaluated by flow-mediated vasodilatation (FMD). The objective of this study was to examine interrelationships between FMD and plasma lipids and lipoproteins, and to determine the between-operator and within-subject variability associated with this technique.

Material And Methods: FMD, plasma lipids and lipoproteins, including small dense LDL (sdLDL), were measured twice in 40 healthy volunteers, 4 weeks apart.

The effect of a combination of plant sterol-enriched foods in mildly hypercholesterolemic subjects.

Background & Aims: The purpose of this study was to evaluate the effect of low-fat products enriched with plant sterols in addition to a National Cholesterol Education Program step 1 diet on serum lipids and lipoproteins.

Methods: This study was a double-blind, randomised, placebo-controlled cross-over design with a run-in period and 2 intervention periods, each lasting 4 weeks. A total of 46 mildly hypercholesterolemic subjects (age 50.

Are selective lung recruitment maneuvers hemodynamically safe in severe hypovolemia? An experimental study in hypovolemic pigs with lobar collapse.

Background: We have previously shown, in normovolemic pigs, that a selective lung recruitment maneuver (S-LRM), i.e., insufflation of air-oxygen via a balloon catheter with its tip located in the bronchus of a collapsed lung lobe, effectively improves oxygenation and lung volume without affecting hemodynamics negatively.

Does a positive end-expiratory pressure-induced reduction in stroke volume indicate preload responsiveness? An experimental study.

Background: Increases in positive end-expiratory pressure (PEEP) are often associated with cardiovascular depression, responding to fluid loading. Therefore, we hypothesized that if stroke volume (SV) is reduced by an increase in PEEP this reduction is an indicator of hypovolemia or preload responsiveness, i.e.

Lipoprotein-associated phospholipase A2 concentrations in plasma are associated with the extent of coronary artery disease and correlate to adipose tissue levels of marine n-3 fatty acids.

Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an emerging risk factor for cardiovascular disease. In the present study, plasma levels of Lp-PLA(2) were measured in patients (n=301) admitted to elective coronary angiography because of suspected coronary artery disease (CAD). In a multiple linear regression analysis, the degree of CAD (0-, 1-, 2- or 3-vessel disease) and plasma LDL cholesterol significantly correlated to Lp-PLA(2) levels.

Fish, marine n-3 polyunsaturated fatty acids and coronary heart disease: a minireview with focus on clinical trial data.

In this paper, we will briefly deal with the background for the possible effects of long-chain marine n-3 (also called omega-3) polyunsaturated fatty acids (PUFA) in coronary heart disease (CHD) and then focus on findings from clinical trials in humans. We will not deal with effects of alpha-linolenic acid, the non-marine type of n-3 PUFA derived from plant oils.

Marine n-3 polyunsaturated fatty acids and coronary heart disease. Part I. Background, epidemiology, animal data, effects on risk factors and safety.

In this paper, we will give an overview of the background for the possible effects of long-chain marine n-3 (synonymously called omega-3) polyunsaturated fatty acids (PUFA) in coronary heart disease (CHD) with focus on recent findings. In a forthcoming paper, we will focus on the clinical trial data, current recommendations and suggest trials to further study the role of marine n-3 PUFA in the prevention and treatment of CHD.

Kinetics of the uptake and distribution of the dopamine D(2,3) agonist (R)-N-[1-(11)C]n-propylnorapomorphine in brain of healthy and MPTP-treated Göttingen miniature pigs.

The binding of radioligand agonists to dopamine receptors in living brain can be informative about the abundance of receptors which are coupled to intracellular second messenger systems. Therefore, we developed a radiosynthesis for the dopamine D(2,3) partial agonist (R)-N- [1-(11)C]n-propylnorapomorphine ([(11)C]NPA). The uptake of this tracer in brain of anesthetized Göttingen miniature pigs was recorded by positron emission tomography (PET) and analyzed by compartmental analysis using the metabolite-corrected arterial input, and using reference tissue methods.

The competition between endogenous dopamine and radioligands for specific binding to dopamine receptors.

The ternary complex model of G-protein-linkage to receptors holds that agonists increase the affinity of the receptors for the G protein. Consequently, an agonist can exert the greatest inhibition of the binding of radioligands which are also agonists. We hypothesized that competition from endogenous dopamine in striatum of living mice should thus have a greater effect on the binding of the D(2,3) agonist N-[(3)H]propylnorapomorphine ([(3)H]NPA), than on the binding of the D(2,3) antagonist [(11)C]raclopride in living brain.

Specific binding of [(11)C]raclopride and N-[(3)H]propyl-norapomorphine to dopamine receptors in living mouse striatum: occupancy by endogenous dopamine and guanosine triphosphate-free G protein.

According to the ternary complex model of G-protein linkage to receptors, agonists increase the affinity of the receptors for the G protein. The model predicts that an endogenous agonist's constant of inhibition toward an agonist radioligand is lower than that toward an antagonistic radioligand. The authors hypothesized that competition from endogenous dopamine in striatum of living mice should have a greater effect on the binding of the D2,3 partial agonist N-[3H]propylnorapomorphine than on the binding of the D2,3 antagonist [(11)C]raclopride.

Comparison of gradient- and spin-echo imaging: CBF, CBV, and MTT measurements by bolus tracking.

The authors measured cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) in pigs by gadodiamide bolus injections and the bolus tracking technique. Two different pulse sequences were applied and compared: gradient-echo (GE) and spin-echo (SE) echoplanar imaging (EPI). After normalization of CBF and CBV values to the area under the arterial input function (AIF), a linear relation between the two methods was found, suggesting that a previous normalization approach for determining absolute CBF by SE EPI may be extended to GE EPI measurements.

The low-power laser in the treatment of tinnitus.

The purpose of this study was to evaluate the low-power laser on the treatment of tinnitus. In a randomized, prospective, double-blind, placebo-controlled trial, either active or placebo low-power laser irradiation was given through the external acoustic meatus of the affected ear towards the cochlea. The active laser applied 50 mW (cw, 830 nm) over a period of 10 min per session.

Localized in vivo 1H NMR spectroscopy of murine tumours: effect of blood flow reduction.

Single voxel 1H localized spectroscopy (PRESS at 300 MHz) was used to monitor physiological and biochemical changes induced by hydralazine (5 mg/kg, i.p.) in murine C3H mammary tumours.

Pattern recognition analysis of 1H NMR spectra from perchloric acid extracts of human brain tumor biopsies.

Pattern recognition techniques (factor analysis and neural networks) were used to investigate and classify human brain tumors based on the 1H NMR spectra of chemically extracted biopsies (n = 118). After removing information from lactate (because of variable ischemia times), unsupervised learning suggested that the spectra separated naturally into two groups: meningiomas and other tumors. Principal component analysis reduced the dimensionality of the data.

Over-mortality as related to age and gender in patients with established non-insulin-dependent diabetes mellitus.

In 1981-1982, 5699 persons representing 92.9% of the total population aged 60-74 years living in Fredericia, Denmark, were interviewed about a possible history of diabetes and had a fasting blood glucose measured. A total of 236 gave a positive history of diabetes; 88 had one fasting blood glucose of 7 mmol/L or more.

Left ventricular opacification after intravenous injection of Albunex. The effect of different administration procedures.

A clinical study has been performed to investigate the influence of different administration procedures on the degree of contrast enhancement of the left ventricle. The administration variables assessed included Albunex injection rate, arm position, flushing rate and flushing fluid. Twenty-four healthy male volunteers were included.