The effect of long-term homocysteine-lowering on carotid intima-media thickness and flow-mediated vasodilation in stroke patients: a randomized controlled trial and meta-analysis

<p>Abstract</p> <p>Background</p> <p>Experimental and epidemiological evidence suggests that homocysteine (tHcy) may be a causal risk factor for atherosclerosis. B-vitamin supplements reduce tHcy and improve endothelial function in short term trials, but the long-term effects of the treatment on vascular structure and function are unknown.</p> <p>Methods</p> <p>We conducted a sub-study of VITATOPS, a randomised, double-blind, placebo-controlled intervention trial designed to test the efficacy of long term B-vitamin supplementation (folic acid 2 mg, vitamin B₆25 mg and vitamin B₁₂0.5 mg) in the prevention of vascular events in patients with a history of stroke. We measured carotid intima-medial thickness (CIMT) and flow-mediated dilation (FMD) at least two years after randomisation in 162 VITATOPS participants. We also conducted a systematic review and meta-analysis of studies designed to test the effect of B-vitamin treatment on CIMT and FMD.</p> <p>Results</p> <p>After a mean treatment period of 3.9 ± 0.9 years, the vitamin-treated group had a significantly lower mean plasma homocysteine concentration than the placebo-treated group (7.9 μmol/L, 95% CI 7.5 to 8.4 versus 11.8 μmol/L, 95% CI 10.9 to 12.8, p < 0.001). Post-treatment CIMT (0.84 ± 0.17 mm vitamins versus 0.83 ± 0.18 mm placebo, p = 0.74) and FMD (median of 4.0%, IQR 0.9 to 7.2 vitamins versus 3.0%, IQR 0.6 to 6.6 placebo, p = 0.48) did not differ significantly between groups. A meta-analysis of published randomised data, including those from the current study, suggested that B-vitamin supplements should reduce CIMT (-0.10 mm, 95% CI -0.20 to -0.01 mm) and increase FMD (1.4%, 95% CI 0.7 to 2.1%). However, the improvement in endothelial function associated with homocysteine-lowering treatment was significant in short-term studies but not in longer trials.</p> <p>Conclusion</p> <p>Although short-term treatment with B-vitamins is associated with increased FMD, long-term homocysteine-lowering did not significantly improve FMD or CIMT in people with a history of stroke.</p> <p>Trial Registration</p> <p>Clinical Trial Registration URL: <url>http://www.actr.org.au/</url></p> <p>Trial Registration number: 12605000005651</p

64-multidetector computed tomographic angiography of the canine coronary arteries

Canine coronary artery angiography (CTA) was performed in four anesthetized healthy dogs using 64-multi-detector computed tomography. Esmolol, a β-1 adrenergic receptor antagonist, and sodium nitroprusside, an arteriolar and venous dilator, were administered to enhance visualization of the coronary arteries by reducing heart rate and creating vasodilation. The left main coronary artery with its three main branches and the right coronary artery were visualized and subdivided in 13 segments for evaluation. Optimal reconstruction interval, expressed as percentage of the R-to-R interval, was determined at 5% in 2.9%, 35% in 1%, 75% in 21.2%, 85% in 43.3%, and 95% in 31.7% of the segments. Overall image quality was good in 41.3% of the segments and excellent in 14.4%. There was blur in 98.1%, motion in 17.3%, and stair step in 6.7% of the evaluated segments, but these artifacts did not interfere with anatomic depiction of the arteries. Cross-sectional anatomy of the coronary arteries as evaluated from the coronary CTA agreed well with gross anatomic evaluation and published information. The use of esmolol did not lead to the target heart rate of 60–65 beats/min. Nitroprusside had no significant effect on visualized length or diameter of the coronary artery branches. Coronary CTA is useful for the anatomic depiction of coronary artery branches in the dog

Helpful and challenging aspects of breastfeeding in public for women living in Australia, Ireland and Sweden: A cross-sectional study

Background: Breastfeeding in public continues to be contentious with qualitative evidence confirming that women face many challenges. It is therefore important to gain understanding of not only the challenges but also what women perceive is helpful to breastfeed in public. Methods: A cross-sectional study was conducted with women living in Australia, Ireland or Sweden currently breastfeeding or having breastfed within the previous 2 years. Our objective was to explore and compare what women do when faced with having to breastfeed in the presence of someone they are uncomfortable with and what women think is helpful and challenging when considering whether to breastfeed in public. Data were collected in 2018 from an online survey over a 4 week period in each country. Content analysis revealed data similarity and theme names and definitions were negotiated until consensus was reached. How often each theme was cited was counted to report frequencies. Helpful and challenging aspects were also ranked by women to allow international comparison. Results: Ten themes emerged around women facing someone they were uncomfortable to breastfeed in the presence of with the most frequently cited being: 'made the effort to be discreet'; 'moved to a private location'; 'turned away' and 'just got on with breastfeeding'. Nine themes captured challenges to breastfeed in public with the following ranked in the top five across countries: 'unwanted attention'; 'no comfortable place to sit'; 'environment not suitable'; 'awkward audience' and 'not wearing appropriate clothing'. Nine themes revealed what was helpful to breastfeed in public with the top five: 'supportive network'; 'quiet private suitable environment'; 'comfortable seating'; 'understanding and acceptance of others' and 'seeing other mothers' breastfeed'. Conclusions: When breastfeeding in public women are challenged by shared concerns around unwanted attention, coping with an awkward audience and unsuitable environments. Women want to feel comfortable when breastfeeding in a public space. How women respond to situations where they are uncomfortable is counterproductive to what they share would be helpful, namely seeing other mothers breastfeed. Themes reveal issues beyond the control of the individual and highlight how the support required by breastfeeding women is a public health responsibility