217 research outputs found
Prenatal Medication Use And Autistic Behaviors In A South Korean Cohort
Autism spectrum disorder (ASD) is thought to result from a combination of genetic and environmental factors, yet a specific cause remains unknown. In this study, exposure and outcome data from a South Korean cohort (N=3,711) were analyzed to investigate the possibility of an environmental contribution to autism etiology. No significant association was observed between use of prenatal medications and autistic behaviors, as measured by Korean versions of both the Autism Spectrum Screening Questionnaire (ASSQ; OR 1.20, 95% CI 0.95–1.51) and the Social Responsiveness Scale (SRS; OR 0.98, 95% CI 0.78–1.25). Similarly, no significant associations were observed when use of prenatal vitamins, folic acid, or iron supplements was examined. There was also no dose-response relationship observed between number of medications taken during pregnancy and increased autistic behaviors. No evidence for a role of prenatal medication use in autism etiology is suggested by the data in this study. Future investigations focusing on specific subgroups of medications in this population are warranted
P2Y12 inhibition in patients with NSTEMI--can later be better
Acute coronary syndrome is an umbrella term that is used to describe the abrupt reduction of blood flow to myocardial tissue, typically associated with the rupture of a coronary atherosclerotic plaque. Rupture exposes the blood to plaque contents, resulting in the deposition and activation of platelets and the formation of thrombi. Complete thrombotic occlusion produces ST-segment elevation myocardial infarction, whereas incomplete impairment of coronary blood flow results in unstable angina or, when biomarkers for myocardial injury are present, non–ST-segment elevation myocardial infarction (NSTEMI). Because the rupture of a plaque incites platelet activation and thrombosis, treatments for unstable angina and NSTEMI have focused on inhibiting platelet function and the coagulation cascade. In patients at high risk for future events (i.e., reinfarction or recurrent ischemia), an early invasive strategy of cardiac catheterization and revascularization is recommended, and in most of these patients intracoronary stents are implanted to treat the plaque rupture. Since stents can produce further plaque trauma, platelet-dependent thrombosis, and embolization into the coronary microcirculation, it is best practice to treat patients with agents that inhibit platelet activation to prevent recurrent ischemia after percutaneous coronary intervention (PCI). As a consequence, current guidelines recommend dual antiplatelet therapy with aspirin plus another agent in patients with NSTEMI who are undergoing PCI
Proof That Lower Is Better--LDL Cholesterol and IMPROVE-IT
The so-called LDL hypothesis is the concept that excess low-density lipoprotein (LDL) cholesterol is a causal factor in the development of atherosclerotic vascular disease. By extension, this hypothesis also assumes that reducing LDL cholesterol levels, regardless of the means, should produce a corresponding reduction in cardiovascular events. Considerable evidence supports the LDL hypothesis, including animal studies and epidemiologic studies involving humans, as well as clinical trials of both statins and nonstatin lipid-modifying agents. In a meta-analysis that included more than 90,000 participants in 14 randomized trials of statins, the Cholesterol Treatment Trialists’ (CTT) collaborators found that, on average, a reduction of 1 mmol per liter (38.7 mg per deciliter) in LDL cholesterol levels yields a consistent 23% reduction in the risk of major coronary events over 5 years
Evanescent wave reduction using a segmented wavemaker in a two dimensional wave tank
The concept of a segmented wavemaker, in a two dimensional
tank, has been investigated analytically to see if it can
reduce the effect of parasitic evanescent waves in a wave tank.
Evanescent waves can contaminate test areas in tanks leading
to unreliable results, but are typically avoided by establishing
the test area two to three times the water depth away from the
wavemaker. This space requirement can be quite restrictive in
terms of the necessary tank size and, with the increasing interest
in off-shore renewable energy, many technology developers may
not be able to afford a workspace large enough to accommodate
a long tank. Previously, flexible wavemakers have been designed
to tackle the problem and, in some cases have proven very effective
in eliminating evanescent waves at the wavemaker’s ”tuned”
frequency. However, flexible wavemakers have been shown to
have little benefit in modeling panchromatic seas. Discussed
here is the linear potential theory of a segmented wavemaker designed
to reduce the evanescent waves in a tank over a large
frequency range. Each segment in the segmented wavemaker is
programmed with an individual stroke, allowing the system to
best approximate the horizontal displacement of the fluid over
the depth of the water in a naturally occurring wave. A comparison
of the influence of evanescent waves created by segmented
wavemakers, piston and hinged paddle wavemakers, on the free
surface elevation is presented
Joseph A. Vita, MD, 1956-2014
On November 2, 2014, our friend and colleague, Joseph Vita, died after a short but gallant struggle with lung cancer at the age of 58. Joe was never a smoker and typically appeared 10 years younger than his age; thus, it was particularly shocking to many when he became ill so suddenly and in his prime. He will be sorely missed; his contributions to cardiovascular medicine were many and diverse. He was a brilliant investigator, a superb clinician, an outstanding mentor, and an expert journal editor
Postmenopausal Hormone Therapy and Atherosclerosis--Time Is of the Essence
In this issue of the Journal, Hodis et al. provide a test of this hypothesis in the Early versus Late Intervention Trial with Estradiol (ELITE)
General practitioner screening for excessive alcohol use. General practitioners' experiences are important.
Short-term e-cigarette vapour exposure causes vascular oxidative stress and dysfunction: evidence for a close connection to brain damage and a key role of the phagocytic NADPH oxidase (NOX-2)
AIMS: Electronic (e)-cigarettes have been marketed as a \u27healthy\u27 alternative to traditional combustible cigarettes and as an effective method of smoking cessation. There are, however, a paucity of data to support these claims. In fact, e-cigarettes are implicated in endothelial dysfunction and oxidative stress in the vasculature and the lungs. The mechanisms underlying these side effects remain unclear. Here, we investigated the effects of e-cigarette vapour on vascular function in smokers and experimental animals to determine the underlying mechanisms.
METHODS AND RESULTS: Acute e-cigarette smoking produced a marked impairment of endothelial function in chronic smokers determined by flow-mediated dilation. In mice, e-cigarette vapour without nicotine had more detrimental effects on endothelial function, markers of oxidative stress, inflammation, and lipid peroxidation than vapour containing nicotine. These effects of e-cigarette vapour were largely absent in mice lacking phagocytic NADPH oxidase (NOX-2) or upon treatment with the endothelin receptor blocker macitentan or the FOXO3 activator bepridil. We also established that the e-cigarette product acrolein, a reactive aldehyde, recapitulated many of the NOX-2-dependent effects of e-cigarette vapour using in vitro blood vessel incubation.
CONCLUSIONS: E-cigarette vapour exposure increases vascular, cerebral, and pulmonary oxidative stress via a NOX-2-dependent mechanism. Our study identifies the toxic aldehyde acrolein as a key mediator of the observed adverse vascular consequences. Thus, e-cigarettes have the potential to induce marked adverse cardiovascular, pulmonary, and cerebrovascular consequences. Since e-cigarette use is increasing, particularly amongst youth, our data suggest that aggressive steps are warranted to limit their health risks
Common Statistical Pitfalls in Basic Science Research
In this review, we focused on common sources of confusion and errors in the analysis and interpretation of basic science studies. The issues addressed are seen repeatedly in the authors\u27 editorial experience, and we hope this article will serve as a guide for those who may submit their basic science studies to journals that publish both clinical and basic science research. We have discussed issues related to sample size and power, study design, data analysis, and presentation of results. We then illustrated these issues using a set of examples from basic science research studies
Short-Term Exposure to Air Pollution and Biomarkers of Oxidative Stress: The Framingham Heart Study
BACKGROUND: Short-term exposure to elevated air pollution has been associated with higher risk of acute cardiovascular diseases, with systemic oxidative stress induced by air pollution hypothesized as an important underlying mechanism. However, few community-based studies have assessed this association.
METHODS AND RESULTS: Two thousand thirty-five Framingham Offspring Cohort participants living within 50 km of the Harvard Boston Supersite who were not current smokers were included. We assessed circulating biomarkers of oxidative stress including blood myeloperoxidase at the seventh examination (1998-2001) and urinary creatinine-indexed 8-epi-prostaglandin F2alpha (8-epi-PGF2alpha) at the seventh and eighth (2005-2008) examinations. We measured fine particulate matter (PM2.5), black carbon, sulfate, nitrogen oxides, and ozone at the Supersite and calculated 1-, 2-, 3-, 5-, and 7-day moving averages of each pollutant. Measured myeloperoxidase and 8-epi-PGF2alpha were loge transformed. We used linear regression models and linear mixed-effects models with random intercepts for myeloperoxidase and indexed 8-epi-PGF2alpha, respectively. Models were adjusted for demographic variables, individual- and area-level measures of socioeconomic position, clinical and lifestyle factors, weather, and temporal trend. We found positive associations of PM2.5 and black carbon with myeloperoxidase across multiple moving averages. Additionally, 2- to 7-day moving averages of PM2.5 and sulfate were consistently positively associated with 8-epi-PGF2alpha. Stronger positive associations of black carbon and sulfate with myeloperoxidase were observed among participants with diabetes than in those without.
CONCLUSIONS: Our community-based investigation supports an association of select markers of ambient air pollution with circulating biomarkers of oxidative stress
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