Marie-France Hétu

Carnitine therapy for the treatment of metabolic syndrome and cardiovascular disease: Evidence and controversies

As the incidence of metabolic syndrome increases, there is also a growing interest in finding safe and inexpensive treatments to help lower associated risk factors. L-carntine, a natural dietary supplement with the potential to ameliorate atherosclerosis, has been the subject of recent investigation and controversy. A majority of studies have shown benefit of L-C supplementation in the metabolic syndrome or cardiovascular risk factors. However, recent work has suggested that dietary L-C may accelerate atherosclerosis via gut microbiota metabolites, complicating the role of L-C supplementation in health.

High root biomass production in anchored Arabidopsis plants grown in axenic sucrose supplemented liquid culture

There are many benefits to growing Arabidopsis in solution-based media, especially when large amounts of root tissue are required for molecular and biochemical studies. Roots grown in soil are brittle and tend to break easily when removed from their substrate. We have developed an axenic liquid culture system that simplifies growing large amounts of roots from intact plants. This technique consists of germinating 15 seeds on 2.5 cm2 stainless steel screens placed on half-strength semisolid Murashige and Skoog medium containing 1% or 2% sucrose. The screens anchor and support the plantlets in an upright position while keeping the roots and shoots separate. The seedlings are transferred with forceps to 125-mL wide-mouth Erlenmeyer flasks containing 10 mL of half-strength Murashige and Skoog liquid medium and 1% sucrose. The flasks are placed onto a floor rotary shaker under fluorescent lights. After 3 days, the sucrose is increased to 3% and the volume to 15 mL for 7 days. During any further experimental manipulations, sucrose is not supplied. The media is changed every 3-4 days to replenish the nutrients. The presence of sucrose in the media dramatically increases the biomass, and large amounts of root tissue can easily be harvested.

Carotid Ultrasound Maximum Plaque Height-A Sensitive Imaging Biomarker for the Assessment of Significant Coronary Artery Disease

We investigated the use of carotid intima–media thickness and carotid plaque in predicting significant angiographic coronary stenosis.

THE EFFECT OF ETHYLENE GLYCOL ON THE PHYTOVOLATILIZATION OF 1,4-DIOXANE

Phytoremediation at contaminated sites is often complicated by the presence of more than one chemical. However, the effects of common co-contaminants such as ethylene glycol on the phytoremediation of other chemicals, e.g., 1,4-dioxane, is not well understood. Field studies with DN34 poplar trees revealed a 28% decline in growth rate in response to 10 g/L ethylene glycol in the groundwater, thus indicating a significant and deleterious effect on tree viability, and likely, the plants’ utility for phytoremediation. Thorough investigations using Arabidopsis thaliana, with its small size and rapid life cycle, indicated significant growth reduction at 10 g/L and complete inhibition of germination at 40 g/L ethylene glycol. Ethylene glycol was almost as severe a stressor as the well characterized osmotic inhibitor, sorbitol. Watering potted trees with 10 g/L ethylene glycol reduced their growth by more than 50%, and similar results were observed in hydroponically grown poplar and willow trees. Under hydroponic conditions, 60 g/L ethylene glycol inhibited the phytovolatilization of 1,4-dioxane by more than 80%, and all trees evapo-transpired 1,4-dioxane less efficiently than water. In fact, this efficiency differed between trees and the difference became more pronounced in the presence of ethylene glycol.

Carotid Plaque or CIMT: What is the Future for Carotid US Imaging?

Carotid intima-media thickness (CIMT) measured by ultrasound has shown value for the prediction and assessment of cardiovascular disease (CVD). Recent advances in technology have now stimulated interest in how quantification of carotid plaque may enhance the utility of CIMT for predicting CVD and assessing atherosclerosis. Total plaque volume (TPV) measured by three-dimensional ultrasound (3D US) appears to have a high sensitivity for angiographic coronary artery disease and is useful for detecting changes in atherosclerotic progression or regression in response to therapy in clinical trials. There continues to be a need to develop a standardized approach to both CIMT and carotid plaque quantification. In the future, plaque quantification is likely to be the main ultrasound measure used in the prediction of cardiovascular disease with CIMT having a complementary role.

Interatrial block predicts atrial fibrillation in patients with carotid and coronary artery disease

Background Interatrial block (IAB) has been previously shown to predict atrial fibrillation (AF) in cardiac populations. This study sought to evaluate the relationship between IAB and new-onset AF in a population of patients undergoing clinically indicated coronary angiography who received carotid ultrasonography. Methods A population of 355 subjects undergoing coronary angiography and carotid ultrasound were retrospectively studied. Common carotid artery (CCA) far-wall intima-media thickness (CIMT), and total carotid plaque area were measured. Coronary artery disease was measured by angiography and IAB by electrocardiograph (ECG). Results The mean population age was 64.4 years, 70.4% male, mean BMI 29.9 kg/m2. IAB was a predictor of new-onset AF (OR =2.40, 95% CI: 1.33-4.29; P=0.003). There was a significant difference in AF free survival time between patients with IAB and without IAB via Cox proportional hazard analysis [52.9 months (95% CI: 47.1-58.7 months) vs. 62.6 months (95% CI: 58.8-66.5 months); P=0.006]. Patients with IAB had a significantly greater CIMT (0.883±0.193 vs. 0.829±0.192 mm; P=0.013) and a higher prevalence of significant (>70%) right coronary artery lesions than patients without (45.8% vs. 34.4%; P=0.026). Significant predictors of IAB on multivariate analysis were BMI ≥30 kg/m2 (OR =3.14, 95% CI: 1.14-6.71, P=0.003), male sex (OR =1.78, 95% CI: 1.05-3.03, P=0.034), increased mean CIMT (per 0.1 mm increase) (OR =1.75, 95% CI: 1.00-3.07, P=0.050) and increased age (per 10-year increase) (OR =1.46, 95% CI: 1.14-1.88, P=0.003). Conclusions IAB is a predictor of new-onset AF in patients with carotid and coronary artery disease. Both carotid and coronary artery disease are associated with a higher prevalence of IAB.

Speckle tracking carotid artery circumferential strain is a marker of arterial sclerosis but not coronary atherosis

Circumferential speckle tracking carotid artery strain is a novel method of quantifying vessel wall stiffness. We hypothesized that carotid wall stiffness would be associated with carotid intimal medial thickening (a medial process associated with risk factors), but not coronary artery disease (an intimal process).