Combined oral contraceptive pills containing desogestrel or drospirenone enhance large vessel and microvasculature vasodilation in healthy premenopausal women

OBJECTIVE: To determine the effects of different COCs on endothelial function. BACKGROUND: COCs all contain ethinylestradiol, but different progestins; three of the more common progestins are DSG, LN, and DR. Ethinylestradiol enhances some measures of vascular reactivity, but certain progestins may increase risk of vascular diseases and impair endothelial vasodilation. METHODS: Twenty-nine healthy women taking COCs containing 30 μg ethinylestradiol and 150 μg DSG (Marvelon, n = 10), 150 μg LN (Microgynon, n = 10), or 3 mg DR (Yasmin, n = 9) had their vascular reactivity measured using various techniques during their pill-free week (days 5-7) and the third week of active pills (days 26-28). A reference group (n = 10) underwent the same measurements on two consecutive cycles. RESULTS: FMD and LDI were significantly higher during active-pill visits than pill-free visits in women taking DSG and DR (p < 0.02), but not in women taking LN. There were no differences between the duplicate measures in the reference group. CONCLUSIONS: COCs containing 150 μg DSG or 3 mg DR significantly increase endothelium-dependent vasodilation in both large vessels and peripheral microvasculature. These effects may be due to the progestins exhibiting differential effects on eNOS expression.

DHA-rich fish oil reverses the detrimental effects of saturated fatty acids on postprandial vascular reactivity

Background: Experimental elevation of nonesterified fatty acids (NEFAs) impairs endothelial function, but the effect of NEFA composition is unknown. Objective: The objective was to test the effect of acute elevation of NEFAs enriched with either saturated fatty acids (SFAs) or SFAs with long-chain (LC) n−3 (omega-3) PUFAs on vascular function measured via flow-mediated dilatation (FMD), laser Doppler iontophoresis (LDI), and digital volume pulse (DVP). Design: In 59 subjects (30 men and 29 women), repeated oral fat feeding of either palm stearin (SFA) or palm stearin with DHA-rich fish oil (SFA + LC n−3 PUFA) was performed on 2 separate occasions with continuous heparin infusion to elevate NEFAs for a duration of 60 to 240 min. Vascular function was measured at baseline and at the end of NEFA elevation; venous blood was collected for measurement of lipids and circulating markers of endothelial function. Results: NEFA elevation during consumption of the SFA-rich drinks was associated with a marked impairment of FMD, whereas consumption of SFAs + LC n−3 PUFAs improved FMD response, with a mean (±SEM) difference of 2.06 ± 0.29% (P < 0.001). Positive correlations were found with percentage weight of LC n−3 PUFAs in circulating NEFAs and change in FMD response [Spearman's rho (rs) = 0.460, P < 0.001]. LDI measures increased during both treatments (P ≤ 0.026), and there was no change in DVP indexes. Conclusions: The composition of NEFAs can acutely affect FMD. The beneficial effect of LC n−3 PUFAs on postprandial vascular function warrants further investigation but may be mediated by nitric oxide–independent mechanisms. This trial is registered at clinicaltrials.gov as NCT01351324.

Knowledge transfer: the facilitating attributes in supply-chain partnerships

This article examines the operational characteristics of supply-chain partnerships and identifies the relational attributes that cultivate knowledge transfer in such partnerships. A set of theoretical propositions are developed. A case study of a computer manufacturer's supply chain was conducted to examine their validity. The findings support the view that trust, commitment, interdependence, shared meaning, and balanced power facilitate knowledge transfer in supply-chain partnerships, and that knowledge transfer should be treated as a dynamic multistage process.

Protecting degraded rainforests: enhancement of forest carbon stocks under REDD+

The likely Reducing Emissions from Deforestation and Degradation (REDD+) mechanism includes strategies for the enhancement of forest carbon stocks. Recent concerns have been expressed that such enhancement, or restoration, of forest carbon could be counterproductive to biodiversity conservation, because forests are managed as “carbon farms” with the application of intensive silvicultural management that could homogenize diverse degraded rainforests. Restoration increases regeneration rates in degraded forest compared to naturally regenerating forest, and thus could yield significant financial returns for carbon sequestered. Here, we argue that such forest restoration projects are, in fact, likely to provide a number of benefits to biodiversity conservation including the retention of biodiversity, the prevention of forest conversion to agriculture, and employment opportunities for poor local communities. As with other forms of forest-based carbon offsets, there are possible moral hazard and leakage problems with restoration. However, due to the multiple benefits, we urge that enhancement of forest carbon stocks be detailed as a major component in the future negotiations of REDD+.