54 research outputs found
HPLC-DAD-ESI-QTOF-MS and HPLC-FLD-MS as valuable tools for the determination of phenolic and other polar compounds in the edible part and by-products of avocado
Avocado is a tropical fruit increasingly cultivated around the world due to global interest and rising consumption. Thus, there is also a surge in avocado by-products that needs assessment. The aim of this work is to compare the phenolic profile of avocado pulp, peel and seed when the fruit is at optimal ripeness for consumption and when overripe. Two analytical techniques were used: (1) HPLC-DAD-ESI-QTOF-MS was used for the first time to determine phenolic and other polar compounds in avocado peel and seed. Phenolic compounds quantified with these methods were in higher concentration in overripe than in pulp and seed of optimally ripe fruit. (2) HPLC-FLD-MS was used to specifically determine flavan-3-ols. Procyanidins to degree of polymerization 13 have been quantified singularly here for the first time. In addition, A- and B-type procyanidins from the degree of polymerization 2 to 6 were differentiated and quantified. The procyanidin concentration increased after ripening probably due to the release of tannins linked to cell-wall structures. Because of this situation and the presence of A-type procyanidins, avocado peel and seed from overripe fruit, the main by-products of avocado processing, hold interest for developing functional foods, nutraceuticals and cosmetics
Geographical variation in therapy for bloodstream infections due to multidrug-resistant enterobacteriaceae: a post hoc analysis of the INCREMENT study
We aimed to describe regional differences in therapy for bloodstream infection (BSI) caused by extended-spectrum ?-lactamase-producing Enterobacteriaceae (ESBL-E) or carbapenemase-producing Enterobacteriaceae (CPE). 1,482 patients in 12 countries were included from an observational study of BSI caused by ESBL-E or CPE. Multivariate logistic regression was used to calculate adjusted odds ratios (aORs) for the influence of country of recruitment on empirical use of ?-lactam/?-lactamase inhibitors (BLBLI) or carbapenems, targeted use of BLBLI for ESBL-E and use of targeted combination therapy for CPE. The use of BLBLI for empirical therapy was least likely in sites from Israel (aOR 0.34, 95% CI 0.14-0.81), Greece (aOR 0.49, 95% CI 0.26-0.94) and Canada (aOR 0.31, 95% CI 0.11-0.88) but more likely in Italy (aOR 1.58, 95% CI 1.11-2.2) and Turkey (aOR 2.09, 95% CI 1.14-3.81), compared to Spain as a reference. Empirical carbapenems were more likely to be used in sites from Taiwan (aOR 1.73, 95% CI 1.03-2.92) and USA (aOR 1.89; 95% CI 1.05-3.39), and less likely in Italy (aOR 0.44, 95% CI 0.28-0.69) and Canada (aOR 0.10, 95% CI 0.01-0.74). Targeted BLBLI for ESBL-E was more likely in sites from Italy. Treatment at sites within Israel, Taiwan, Turkey and Brazil was associated with less combination therapy for CPE. Although this study does not provide precise data on the relative prevalence of ESBL-E or CPE, significant variation in therapy exists across countries even after adjustment for patient factors. A better understanding of what influences therapeutic choices for these infections will aid antimicrobial stewardship efforts.PH is supported by an Australian Postgraduate Award from the University of
Queensland. The study was funded by the Ministerio de EconomĂa y Competitividad,
Instituto de Salud Carlos III - co-financed by European Development Regional Fund "A way to
achieve Europe" ERDF, Spanish Network for the Research in Infectious Diseases (REIPI
RD12/0015). BGG, JRB, APH and YC also received funds from the COMBACTE-CARE
project (grant agreement 115620), Innovative Medicines Initiative (IMI), the European
Union's Seventh Framework Programme (FP7/2007-2013) and in-kind contributions from
EFPIA companies
Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study
Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28â2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65â3·22], p\textless0·0001), American Society of Anesthesiologists grades 3â5 versus grades 1â2 (2·35 [1·57â3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01â2·39], p=0·046), emergency versus elective surgery (1·67 [1·06â2·63], p=0·026), and major versus minor surgery (1·52 [1·01â2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
Search for flavor-changing neutral current interactions of the top quark and the Higgs boson decaying to a bottom quark-antiquark pair at â s = 13 TeV
A preprint version of the article is available at arXiv (https://arxiv.org/abs/2112.09734).Copyright © CERN, for the benefit of the CMS Collaboration. A search for flavor-changing neutral current interactions of the top quark (t) and the Higgs boson (H) is presented. The search is based on a data sample corresponding to an integrated luminosity of 137 fbâ1 recorded by the CMS experiment at the LHC in proton-proton collisions at sâ = 13 TeV. Events containing exactly one lepton (muon or electron) and at least three jets, among which at least two are identified as originating from the hadronization of a bottom quark, are analyzed. A set of deep neural networks is used for kinematic event reconstruction, while boosted decision trees distinguish the signal from the background events. No significant excess over the background predictions is observed, and upper limits on the signal production cross sections are extracted. These limits are interpreted in terms of top quark decay branching fractions (B) to the Higgs boson and an up (u) or a charm quark (c). Assuming one nonvanishing extra coupling at a time, the observed (expected) upper limits at 95% confidence level are B(t â Hu) < 0.079 (0.11)% and B(t â Hc) < 0.094 (0.086)%.SCOAP3
Search for long-lived particles decaying to leptons with large impact parameter in proton-proton collisions at root s=13 TeV
A search for new long-lived particles decaying to leptons using protonâproton collision data produced by the CERN LHC at sâ=13TeV is presented. Events are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10cm and are not required to form a common vertex. Data used for the analysis were collected with the CMS detector in 2016, 2017, and 2018, and correspond to an integrated luminosity of 118 (113)fbâ1 in the ee channel (eÎŒ and ΌΌ channels). The search is designed to be sensitive to a wide range of models with displaced eÎŒ, ee, and ΌΌ final states. The results constrain several well-motivated models involving new long-lived particles that decay to displaced leptons. For some areas of the available phase space, these are the most stringent constraints to date
Monitoring of Bioactive Compounds from Hojiblanca Extra Virgin Olive Oil Variety and Olive Oil Byproducts During Storage Time
Extra Virgin Olive Oil (EVOO), the juice derived from the first cold pressing of the olives without any further refining process, naturally contains high levels of phenolic compounds associated with the health benefits. Indeed, these compounds exert strong antiproliferative effects on many pathological processes, which have stimulated chemical characterization of the large quantities of wastes generated during olive oil production. In the Mediterranean area, EVOO is produced from September to February, and oil is generally stored in the mill plant until commercialization. During this storage time suspended solids and others materials are deposited by precipitation in the bottom of the tank generating a solid waste. Phenolic fraction has been previously assessed in these byproducts which can be considered an important natural source of phenolic compounds, mainly hydroxytyrosol, tyrosol and decarboxymethyl oleuropein aglycone.
In this investigation, phenolic profile on EVOO and solid waste generated during storage has been monitored using solid phase and solid\u2013liquid extraction processes followed by high performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (TOF-MS). EVOO from Hojiblanca variety was obtained and stored in ten tanks without headspace at room temperature in darkness. In order to monitoring phenolic profile in both, EVOO and solid waste, sample collection and phenolic compound extraction were carried out every thirty days during a period of ten months. Half-life (t1/2) of the individual compounds was calculated as ln 2/ Kel, where Kel (elimination rate constant) was established from the slope of the elimination phase in the concentration vs. time plot.
A variable trend was observed for phenolic content in both, EVOO and byproducts, during the storage. Qualitative results of phenolic and derived compounds in EVOO and storage byproduct suggested degradation pathways which were confirmed taking into account half-life and Kel for the complex phenols and their oxidized and hydrolyzed derivatives. Indeed, when the correlation for the pair oleuropein aglycone or decarboxymethyl oleuropein aglycon and their hydrolyzed derivatives was evaluated, the determination coefficients (r2) were higher than 0.970. These results showed the trend of the phenolic compounds in EVOO as well as byproduct during storage time, which are of great value in establishing of the EVOO quality and solid waste. These phenolic molecules, after suitable purification, can be used as food antioxidants or as ingredients in nutraceutical products due to their interesting technological and pharmaceutical properties
Determination of the Major Phenolic Compounds in Pomegranate Juices by HPLC\u2013DAD\u2013ESI-MS
Traditionally, pomegranate (Punica granatum L.) has been consumed as fresh fruit or as pomegranate juice. In this study, the main phenolic compounds of 12 pomegranate varieties and 5 pomegranate clones were determined by HPLC-DAD-ESI-MS. Two chromatographic methods with a fused-core C18 column and a classical HPLC system were developed. Thirteen anthocyanins and fourteen other phenolic compounds were determined in the pomegranate juices. As far as we are concerned, a new flavonol-glycoside, phellatin or its isomer amurensin, has been tentatively identified for the first time in pomegranate juices. Total phenolic content ranged from 580.8 to 2551.3 mg/L of pomegranate juice. Anthocyanins varied between 20 to 82% of total phenolic content. Flavonoids were 1.6-23.6% of total phenolic compounds, while phenolic acids and ellagitannins were in the range 16.4-65.8%. The five clones reported a phenolic content comparable with that of the other pomegranate samples
Analytical determination of polyphenols in olive oils
An overview of analytical methods for the measurement of polyphenols in olive oil is presented. A great number of procedures for the isolation of the polar phenolic fraction of virgin olive oil, utilizing two basic extraction techniques, LLE or SPE, have been included. The reviewed techniques are those based on spectrophotometric methods, as well as analytical separation (gas chromatography (GC), high-performance liquid chromatography (HPLC), and capillary electrophoresis (CE))
Development of a rapid method to determine phenolic and other polar compounds in walnut by capillary electrophoresis\u2013electrospray ionization time-of-flight mass spectrometry
The aim of this work was to develop a capillary electrophoresis\u2013mass spectrometry (CE\u2013MS) method to identify and quantify phenolic and other related polar compounds in walnut samples. The extraction capacity of several solvent mixtures of phenolic compounds from walnut by conventional solid\u2013liquid extractions was tested, and CE and electrospray ionization MS parameters were optimized. The finalized procedure is able to determine many well-known phenolic compounds present in walnuts and provide
relevant information about the presence of minor polar compounds. A new compound in walnut ((2E,4E)-8-hydroxy-2,7-dimethyl-2,4-decadiene-1,10-dioic acid 6-O-beta-d-glucopiranosyl ester, [M−H]−
403.161m/z) with a structure similar to glansregininswas also identified. Phenolic compounds correspond to 14\u201328% of total polar compounds quantified. Aglycone and glycosylated ellagic acid represent the principalcomponents and account for 64\u201375% of total phenols inwalnuts.However, thesumof glansregininsA, B and (2E,4E)-8-hydroxy-2,7-dimethyl-2,4-decadiene-1,10-dioic acid 6-O--d-glucopiranosyl ester was in the range of 72\u201386% of total quantified compounds. In addition, this is the first time that separation by CE with detection by electrospray ionization time-of-flightMShas been applied to the analysis of phenolic and other polar compounds in walnut samples, providing results in less than 15 min
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