Amperometric enzyme sensor to check the total antioxidant capacity of several mixed berries. comparison with two other spectrophotometric and fluorimetric methods

The aim of this research was to test the correctness of response of a superoxide dismutase amperometric biosensor used for the purpose of measuring and ranking the total antioxidant capacity of several systematically analysed mixed berries. Several methods are described in the literature for determining antioxidant capacity, each culminating in the construction of an antioxidant capacity scale and each using its own unit of measurement. It was therefore endeavoured to correlate and compare the results obtained using the present amperometric biosensor method with those resulting from two other different methods for determining the total antioxidant capacity selected from among those more frequently cited in the literature. The purpose was to establish a methodological approach consisting in the simultaneous application of different methods that it would be possible to use to obtain an accurate estimation of the total antioxidant capacity of different mixed berries and the food product

Catalytic fuel cell used as an analytical tool for methanol and ethanol determination. Application to ethanol determination in alcoholic beverages

A small direct catalytic methanol 'fuel cell' was used for analytical purposes. Three different formats were investigated for methanol and ethanol determination: two different Open Circuit Voltage (OCV) formats and a potentiostatic (i.e. amperometric) format; the latter was used if the current supplied by the cell was recorded. The measurement times using one or other of these three formats were much different. The time required by the potentiostatic format was more short for a suitable analytical measurement. The cell was used to check ethanol content in several commercial wine and beer samples and the possibility of using the fuel cell for the analytical measures in real samples, discussed. Lastly the results were compared with those obtained using two conventional amperometric enzyme sensors and statistical tests carried out. (C) 2016 Elsevier Ltd. All rights reserved

Bioethanol in biofuels checked by an amperometric organic phase enzyme electrode (OPEE) working in “substrate antagonism” format

The bioethanol content of two samples of biofuels was determined directly, after simple dilution in decane, by means of an amperometric catalase enzyme biosensor working in the organic phase, based on substrate antagonisms format. The results were good from the point of view of accuracy, and satisfactory for what concerns the recovery test by the standard addition method. Limit of detection (LOD) was on the order of 2.5 × 10−5 M. © 2016 by the authors; licensee MDPI, Basel, Switzerland

Unilateral versus bilateral antegrade cerebral protection during circulatory arrest in aortic surgery: A meta-analysis of 5100 patients

ObjectiveOur objective was to determine whether the use of unilateral (u-ACP) or bilateral antegrade cerebral perfusion (b-ACP) results in different mortality and neurologic outcomes after complex aortic surgery.MethodsPubMed, Embase, and the Cochrane Library were searched for studies reporting on postoperative mortality and permanent (PND) and temporary neurologic dysfunction (TND) in complex aortic surgery requiring circulatory arrest with antegrade cerebral protection. Analysis of heterogeneity was performed with the Cochrane Q statistic.ResultsTwenty-eight studies were analyzed for a total of 1894 patients receiving u-ACP versus 3206 receiving b-ACP. Pooled analysis showed similar rates of 30-day mortality (8.6% vs 9.2% for u-ACP and b-ACP, respectively; P = .78), PND (6.1% vs 6.5%; P = .80), and TND (7.1% vs 8.8%; P = .46). Age, sex, and cardiopulmonary bypass time did not influence effect size estimates. Higher rates of postoperative mortality and PND were among nonelective operations and for highest temperatures and duration of the circulatory arrest. The Egger test excluded publication bias for the outcomes investigated.ConclusionsThis meta-analysis shows that b-ACP and u-ACP have similar postoperative mortality and both PND and TND rates after circulatory arrest for complex aortic surgery

Assessment and Comparison of Phytochemical Constituents and Biological Activities between Full Flowering and Late Flowering of Hypericum perforatum L.

This study assessed the impact of full and late flowering stages on the polyphenols and enzyme inhibitory properties of Hypericum perforatum from Poland. Recognizing the significance of phenolic compounds in disease prevention and melatonin’s emerging protective role, we employed an UHPLC-MS/MS system to quantify 38 phenolic compounds, not typical of St. John’s wort, and to develop a new method for melatonin quantification. Afterward, the extracts were tested for their antioxidant capabilities (using phosphomolybdenum, DPPH, ABTS, FRAP, CUPRAC and ferrous chelating assays). Moreover, we investigated enzymes (acetylcholinesterase, butyrylcholinesterase and tyrosinase) involved in neurodegenerative disorders and (α-amylase and α-glucosidase) in diabetes. This study recognized the importance of phenolic compounds in disease prevention and explored the emerging protective role of melatonin, taking into account the floral ontogeny of the plant. Indeed, the full-flowering plant contained the greatest concentration of phenolic compounds (a total of 65,276.5 μg/g): hyperoside (18,726.59 μg/g), isoquercitrin (11,895.02 μg/g) and delphindin-3.5-diglucoside (10,619.51 μg/g), and showed the highest inhibitory enzyme activity. Moreover, only full-flowering St. John’s wort contained melatonin (40 ng/g). Our results offer additional perspectives on the chemical-biological characteristics of H. perforatum and scientific knowledge that testifies to the importance of considering plant growth conditions for the development of nutraceuticals

Lack of protective role of HDL-C in patients with coronary artery disease undergoing elective coronary artery bypass grafting

Aims Primary prevention studies have confirmed that high-density lipoprotein cholesterol (HDL-C) levels are strongly associated with reduced cardiovascular events. However, recent evidence suggests that HDL-C functionality may be impaired under certain conditions. In the present study, we hypothesize that HDL-C may lose their protective role in the secondary prevention of coronary artery disease (CAD). Methods and results A consecutive series of 1548 patients undergoing isolated first-time elective CABG at one institution between 2004 and 2009 was studied. According to the ATPIII criteria, pre-operative HDL-C values were used to identify patients with high (Group A) vs. low HDL-C (Group B). To eliminate biased estimates, a propensity score model was built and two cohorts of 1:1 optimally matched patients were obtained. Cumulative survival and major adverse cardiovascular events (MACE) were analysed by means of Kaplan-Meier method. Cox proportional-hazards regression models were used to identify independent predictors of MACE and death. Propensity matching identified two cohorts of 502 patients each. At a median follow-up time of 32 months, there were 44 out of 502 (8.8%) deaths in Group A and 36 out of 502 deaths in Group B (7.2%, HR 1.19; P = 0.42). MACE occurred in 165 out of 502 (32.9%) in Group A and 120 out of 502 (23.9%) in Group B (P = 0.04). Regression analysis showed that pre-operative HDL-C levels were not associated with reduced but rather increased MACE occurrence during follow-up (HR 1.43, P = 0.11). Conclusion Higher HDL-C levels are not associated with reduced risk of vascular events in CAD patients undergoing CABG. Our findings may support efforts to improve HDL-C functionality instead of increasing their level

Identification of Anti-Neuroinflammatory Bioactive Compounds in Essential Oils and Aqueous Distillation Residues Obtained from Commercial Varieties of Cannabis sativa L

Neuroinflammation, which is mainly triggered by microglia, is a key contributor to multiple neurodegenerative diseases. Natural products, and in particular Cannabis sativa L., due to its richness in phytochemical components, represent ideal candidates to counteract neuroinflammation. We previously characterized different C. sativa commercial varieties which showed significantly different chemical profiles. On these bases, the aim of this study was to evaluate essential oils and aqueous distillation residues from the inflorescences of three different hemp varieties for their anti-neuroinflammatory activity in BV-2 microglial cells. Cells were pretreated with aqueous residues or essential oils and then activated with LPS. Unlike essential oils, aqueous residues showed negligible effects in terms of anti-inflammatory activity. Among the essential oils, the one obtained from 'Gorilla Glue' was the most effective in inhibiting pro-inflammatory mediators and in upregulating anti-inflammatory ones through the modulation of the p38 MAPK/NF-kappa B pathway. Moreover, the sesquiterpenes (E)-caryophyllene, alpha-humulene, and caryophyllene oxide were identified as the main contributors to the essential oils' anti-inflammatory activity. To our knowledge, the anti-neuroinflammatory activity of alpha-humulene has not been previously described. In conclusion, our work shows that C. sativa essential oils characterized by high levels of sesquiterpenes can be promising candidates in the prevention/counteraction of neuroinflammation