Characterization of the Volatile Components of Cannabis Preparations by Solid-Phase Microextraction Coupled to Headspace-Gas Chromatography with Mass Detector (SPME-HSGC/MS)

Solid phase microextraction coupled to headspace sampling and GC/MS technique was applied to the characterization of the volatile components of several Cannabis preparations (hashish). Different parameters of the analytical method (fiber, coating thickness, sampling and exposition temperatures, sample preparation) were evaluated to optimize the characterization of the volatile components. a-Pinene, f-myrcene, limonene, 4-carene, trans-3(10) caren-2-ol, 4,7,7-trimethylbicyclo [4.1.0] heptan-3-ol, caryophyllene, f-humulene, azulene, gurjunene, ledene and caryophyllene oxide were identified among the volatile components of all hashish preparations. Moreover, a suitable internal standard (nonane) was chosen, the reproducibility and linearity of the method were evaluated in order to carry out the quantitative determination of caryphyllene, the most abundant volatile terpene. Its quantity ranged from 800 to 3000 \ub5g/g

On the Generalizability of Experimental Results

The age-old question of the generalizability of the results of experiments that are conducted in artificial laboratory settings to more realistic inferential and decision making situations is considered in this paper. Conservatism in probability revision provides an example of a result that 1) has received wide attention, including attention in terms of implications for real-world decision making, on the basis of experiments conducted in artificial settings and 2) is now apparently thought by many to be highly situational and not at all a ubiquitous phenomenon, in which case its implications for real-world decision making are not as extensive as originally claimed. In this paper we consider the questions of generalizations from the laboratory to the real world in some detail, both within the context of the experiments regarding conservatism and within a more general context. In addition, we discuss some of the difficulties inherent in experimentation in realistic settings, suggest possible procedures for avoiding or at least alleviating such difficulties, and make a plea for more realistic experiments

Effects of the long-term administration of nebivolol on the clinical symptoms, exercise capacity, and left ventricular function of patients with diastolic dysfunction: results of the ELANDD study

AIMS: We hypothesized that nebivolol, a beta-blocker with nitric oxide-releasing properties, could favourably affect exercise capacity in patients with heart failure and preserved left ventricular ejection fraction (HFPEF). METHODS AND RESULTS: A total of 116 subjects with HFPEF, in New York Heart Association (NYHA) functional class II-III, with left ventricular ejection fraction (LVEF) >45%, and with echo-Doppler signs of LV diastolic dysfunction, were randomized to 6 months treatment with nebivolol or placebo, following a double-blind, parallel group design. The primary endpoint of the study was the change in 6 min walk test distance (6MWTD) after 6 months. Nebivolol did not improve 6MWTD (from 420 ± 143 to 428 ± 141 m with nebivolol vs. from 412 ± 123 to 446 ± 119 m with placebo, P = 0.004 for interaction) compared with placebo, and the peak oxygen uptake also remained unchanged (peakVO(2); from 17.02 ± 4.79 to 16.32 ± 3.76 mL/kg/min with nebivolol vs. from 17.79 ± 5.96 to 18.59 ± 5.64 mL/kg/min with placebo, P = 0.63 for interaction). Resting and peak blood pressure and heart rate decreased with nebivolol. A significant correlation was found between the change in peak exercise heart rate and that in peakVO(2) (r = 0.391; P = 0.003) for the nebivolol group. Quality of life, assessed using the Minnesota Living with Heart Failure Questionnaire, and NYHA classification improved to a similar extent in both groups, whereas N-terminal pro brain natriuretic peptide (NT-pro BNP) plasma levels remained unchanged. CONCLUSIONS: Compared with placebo, 6 months treatment with nebivolol did not improve exercise capacity in patients with HFPEF. Its negative chronotropic effect may have contributed to this result

Metabolic exercise test data combined with cardiac and kidney indexes, the MECKI score: a multiparametric approach to heart failure prognosis

OBJECTIVES: We built and validated a new heart failure (HF) prognostic model which integrates cardiopulmonary exercise test (CPET) parameters with easy-to-obtain clinical, laboratory, and echocardiographic variables. BACKGROUND: HF prognostication is a challenging medical judgment, constrained by a magnitude of uncertainty. METHODS: Our risk model was derived from a cohort of 2716 systolic HF patients followed in 13 Italian centers. Median follow up was 1041days (range 4-5185). Cox proportional hazard regression analysis with stepwise selection of variables was used, followed by cross-validation procedure. The study end-point was a composite of cardiovascular death and urgent heart transplant. RESULTS: Six variables (hemoglobin, Na(+), kidney function by means of MDRD, left ventricle ejection fraction [echocardiography], peak oxygen consumption [% pred] and VE/VCO(2) slope) out of the several evaluated resulted independently related to prognosis. A score was built from Metabolic Exercise Cardiac Kidney Indexes, the MECKI score, which identified the risk of study end-point with AUC values of 0.804 (0.754-0.852) at 1year, 0.789 (0.750-0.828) at 2years, 0.762 (0.726-0.799) at 3years and 0.760 (0.724-0.796) at 4years. CONCLUSIONS: This is the first large-scale multicenter study where a prognostic score, the MECKI score, has been built for systolic HF patients considering CPET data combined with clinical, laboratory and echocardiographic measurements. In the present population, the MECKI score has been successfully validated, performing very high AUC

Authorship: From Credit to Accountability

The Editors' Network of the European Society of Cardiology (ESC) provides a dynamic forum for editorial discussions and endorses the recommendations of the International Committee of Medical Journal Editors (ICMJE) to improve the scientific quality of biomedical journals. Authorship confers credit and important academic rewards. Recently, however, the ICMJE emphasized that authorship also requires responsibility and accountability. These issues are now covered by the new (fourth) criterion for authorship. Authors should agree to be accountable and ensure that questions regarding the accuracy and integrity of the entire work will be appropriately addressed. This review discusses the implications of this paradigm shift on authorship requirements with the aim of increasing awareness on good scientific and editorial practices

Renal function and peak exercise oxygen consumption in chronic heart failure with reduced left ventricular ejection fraction

Background: Chronic kidney disease is associated with sympathetic activation and muscle abnormalities, which may contribute to decreased exercise capacity. We investigated the correlation of renal function with peak exercise oxygen consumption (V\u2d9O2) in heart failure (HF) patients. Methods and Results: We recruited 2,938 systolic HF patients who underwent clinical, laboratory, echocardiographic and cardiopulmonary exercise testing. The patients were stratified according to estimated glomerular filtration rate (eGFR). Mean follow-up was 3.7 years. The primary outcome was a composite of cardiovascular death and urgent heart transplantation at 3 years. On multivariable regression, eGFR was predictor of peakV\u2d9O2 (P<0.0001). Other predictors were age, sex, body mass index, HF etiology, NYHA class, atrial fibrillation, resting heart rate, Btype natriuretic peptide, hemoglobin, and treatment. After adjusting for significant covariates, the hazard ratio for primary outcome associated with peakVO2 <12 ml \u30fb kg 121 \u30fb min 121 was 1.75 (95% confidence interval (CI): 1.06\u20132.91; P=0.0292) in patients with eGFR 6560, 1.77 (0.87\u20133.61; P=0.1141) in those with eGFR of 45\u201359, and 2.72 (1.01\u2013 7.37; P=0.0489) in those with eGFR <45 ml \u30fb min 121 \u30fb 1.73 m 122. The area under the receiver-operating characteristic curve for peakV\u2d9O2 <12 ml \u30fb kg 121 \u30fb min 121 was 0.63 (95% CI: 0.54\u20130.71), 0.67 (0.56\u20130.78), and 0.57 (0.47\u20130.69), respectively. Testing for interaction was not significant. Conclusions: Renal dysfunction is correlated with peakV O2. A peakV O2 cutoff of 12 ml \u30fb kg\u20131 \u30fb min\u20131 offers limited prognostic information in HF patients with more severely impaired renal function