An Adaptive Markov Chain Monte Carlo Method for GARCH Model

We propose a method to construct a proposal density for the Metropolis-Hastings algorithm in Markov Chain Monte Carlo (MCMC) simulations of the GARCH model. The proposal density is constructed adaptively by using the data sampled by the MCMC metho d itself. It turns out that autocorrelations between the data generated with our adaptive proposal density are greatly reduced. Thus it is concluded that the adaptive construction method is very efficient and works well for the MCMC simulations of the GARCH model.Comment: 11 pages, 6 figure

Modulation of dendritic cell alternative activation and function by the vitamin A metabolite retinoic acid

The archetypal Th2 cytokine IL-4 has previously been shown to alternatively activate murine macrophages and, more recently, dendritic cells (DCs) both in vitro and in vivo. IL-4 has also been shown to induce Aldh1a2 (aldehyde dehydrogenase 1a2) expression in murine macrophages recruited to the peritoneal cavity. However, the influence of IL-4 on DC Aldh1a2 induction in vivo has not yet been addressed. In this work, we found that DCs show enhanced aldehyde dehydrogenase enzyme activity in vivo, which led us to investigate the impact of the vitamin A metabolite all-trans retinoic acid (RA) on DC alternative activation and function. Antagonism of RA receptors reduced production of resistin-like molecule alpha by DCs responding to IL-4, while addition of exogenous RA enhanced production of this marker of alternative activation. Functionally, RA increased DC induction of CD4(+) T-cell IL-10, while reducing CD4(+) T-cell IL-4 and IL-13, revealing a previously unidentified role for RA in regulating the ability of alternatively activated DCs to influence Th2 polarization

Mechanisms of T cell organotropism

F.M.M.-B. is supported by the British Heart Foundation, the Medical Research Council of the UK and the Gates Foundation

Clinical Efficacy of Thrombus Aspiration on 5-Year Clinical Outcomes in Patients With ST-Segment Elevation Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention.

Background: Adjunctive thrombus aspiration (TA) during primary percutaneous coronary intervention (PCI) was reported to promote better coronary and myocardial reperfusion. However, long‐term mortality benefit of TA remains controversial. The objective of this study is to investigate the clinical impact of TA on long‐term clinical outcomes in patients with ST‐segment elevation myocardial infarction (STEMI) undergoing primary PCI. Methods and Results: The CREDO‐Kyoto AMI Registry is a large‐scale cohort study of acute myocardial infarction patients undergoing coronary revascularization in 2005–2007 at 26 hospitals in Japan. Among 5429 patients enrolled in the registry, the current study population consisted of 3536 patients who arrived at the hospital within 12 hours after the symptom onset and underwent primary PCI. Clinical outcomes were compared between the 2 patient groups with or without TA. During primary PCI procedures, 2239 out of 3536 (63%) patients underwent TA (TA group). The cumulative 5‐year incidence of all‐cause death was significantly lower in the TA group than in the non‐TA group (18.5% versus 23.9%, log‐rank P<0.001). After adjusting for confounders, however, the risk for all‐cause death in the TA group was not significantly lower than that in the non‐TA group (hazard ratio: 0.90, 95% CI: 0.76 to 1.06, P=0.21). The adjusted risks for cardiac death, myocardial infarction, stroke, and target‐lesion revascularization were also not significantly different between the 2 groups. Conclusions: Adjunctive TA during primary PCI was not associated with better 5‐year mortality in STEMI patients