299 research outputs found
Relationship between systolic time intervals and arterial blood pressure.
It has been suggested that systolic time intervals (STI) can be used to monitor the cardiac effects of antihypertensive treatments and also to evaluate hypertensive patients. STI changes observed in hypertensives have been ascribed to myocardial disease, although they could be due to the existence of a relationship between STI and blood pressure. A group of 37 subjects (18 normotensives and 19 hypertensives) with no signs of heart failure and left ventricular dysfunction were studied to examine the relationship of STI to blood pressure. Pacing with an external battery pulse generator was performed at the rate of 95 beats/min in order to eliminate differences in heart rate. STI were measured from good quality high speed (100 mm/s) recordings and the average value of 10 consecutive cardiac cycles was used for statistical analysis. Normal subjects showed significantly lower values of pre-ejection period (PEP), electromechanical systole (QS2), and pre-ejection period/left ventricular ejection time ratio (PEP/LVET). Moreover, a significant inverse relationship between diastolic pressure and LVET and significant direct relationships between diastolic pressure and PEP, systolic pressure and PEP, diastolic pressure and PEP/LVET, and between systolic pressure and PEP/LVET were demonstrated. We suggest to consider the relation of STI to blood pressure to provide regression equations to best appreciate and use STI
Cambios en aceites de oliva usados como coberturas en la conservación de berenjenas (Solanum Melongena) en relación con el tiempo y las condiciones de almacenamiento
The use of the extra virgin olive oil as covering in food preserves presents some problems and still today object of study. With this research it was investigate the changes of some analytical parameters that occur during the storage in the olive oils used as covering in eggplant preserves. It was ascertained that in the oils in presence of the eggplants a drastic decrease of the total phenols was verified immediately after the thermal treatment affecting the oxidative processes. Besides it was observed that in all the oils stored under light the values of the K270. ΔK, the total chlorophylls and the 1,2-DG36/1,3-DG36 ratio were significantly changed.El uso de aceite de oliva virgen extra como cobertura en conservas alimentarias presenta una serie de problemas que son todavía hoy objeto de estudio. El objetivo de este estudio fue investigar los cambios de algunos parámetros analíticos producidos durante el almacenamiento en aceite de oliva usado como cobertura en la conservación de berenjenas. Se encontró que el aceite que ha estado en contacto con las berenjenas, sufrió una disminución de los fenoles totales inmediatamente después del tratamiento térmico, afectando a los procesos oxidativos. Se observó asimismo, que en todos los aceites almacenados a la luz variaron significativamente los valores del K270, del ΔK, de la clorofila y de la proporción de 1,2-DG36/1,3- DG36
Incidence of pneumomediastinum in COVID-19: A single-center comparison between 1st and 2nd wave
In this study, we compared the incidence of pneumomediastinum in coronavirus disease (COVID-19) patients during the ascending phases of the 1st and 2nd epidemic waves. Crude incidence was higher during the 2nd wave at a quasi-significant level (0.68/1000 vs. 2.05/1000 patient-days, p = 0.05). When restricting the analysis to patients who developed pneumomediastinum during noninvasive ventilation, the difference became clearly significant (0.17/1000 vs 1.36/1000 patient-days, p = 0.039). At logistic regression, predisposing factors (p = 0.031), and COVID-19 radiological severity (p = 0.019) were independently associated with pneumomediastinum. Mortality in patients with pneumomediastinum was 87.5%. However, pneumomediastinum seemed to be related to a generally worse disease presentation in hospitalized patients during the 2nd wave, rather than to a separate pattern of disease. (C) 2021 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved
Diamond Detectors for the TOTEM Timing Upgrade
This paper describes the design and the performance of the timing detector
developed by the TOTEM Collaboration for the Roman Pots (RPs) to measure the
Time-Of-Flight (TOF) of the protons produced in central diffractive
interactions at the LHC. The measurement of the TOF of the protons allows the
determination of the longitudinal position of the proton interaction vertex and
its association with one of the vertices reconstructed by the CMS detectors.
The TOF detector is based on single crystal Chemical Vapor Deposition (scCVD)
diamond plates and is designed to measure the protons TOF with about 50 ps time
precision. This upgrade to the TOTEM apparatus will be used in the LHC run 2
and will tag the central diffractive events up to an interaction pileup of
about 1. A dedicated fast and low noise electronics for the signal
amplification has been developed. The digitization of the diamond signal is
performed by sampling the waveform. After introducing the physics studies that
will most profit from the addition of these new detectors, we discuss in detail
the optimization and the performance of the first TOF detector installed in the
LHC in November 2015.Comment: 26 pages, 18 figures, 2 tables, submitted for publication to JINS
Evidence for non-exponential elastic proton-proton differential cross-section at low |t| and sqrt(s) = 8 TeV by TOTEM
The TOTEM experiment has made a precise measurement of the elastic
proton-proton differential cross-section at the centre-of-mass energy sqrt(s) =
8 TeV based on a high-statistics data sample obtained with the beta* = 90
optics. Both the statistical and systematic uncertainties remain below 1%,
except for the t-independent contribution from the overall normalisation. This
unprecedented precision allows to exclude a purely exponential differential
cross-section in the range of four-momentum transfer squared 0.027 < |t| < 0.2
GeV^2 with a significance greater than 7 sigma. Two extended parametrisations,
with quadratic and cubic polynomials in the exponent, are shown to be well
compatible with the data. Using them for the differential cross-section
extrapolation to t = 0, and further applying the optical theorem, yields total
cross-section estimates of (101.5 +- 2.1) mb and (101.9 +- 2.1) mb,
respectively, in agreement with previous TOTEM measurements.Comment: Final version published in Nuclear Physics
Progression and mortality in patients with CKD attending outpatient nephrology clinics across Europe: A novel analytic approach
The incidence of renal replacement therapy (RRT) varies across countries. Yet, little is known about the epidemiology of chronic kidney disease (CKD) outcomes. Our aim was to describe progression and mortality risk in CKD patients not on RRT attending outpatient nephrology clinics across Europe.
We used individual data from nine CKD cohorts participating in the European CKD Burden Consortium. A joint model was used to estimate mean eGFR change and mortality risk simultaneously, thereby accounting for mortality risk when estimating eGFR decline and vice versa, while also correcting for the measurement error in eGFR. Results were adjusted for important risk factors (baseline eGFR, age, sex, albuminuria, primary renal disease, diabetes, hypertension, obesity and smoking).
27,771 patients from five countries were included. The adjusted mean annual eGFR decline varied from 0.77 (95%CI 0.45,1.08) ml/min/1.73m2 in the Belgium cohort to 2.43 (95%CI 2.11,2.75) ml/min/1.73m2 in the Spanish cohort. As compared to the Italian PIRP cohort, the adjusted mortality hazard ratio varied from 0.22 (95%CI 0.11,0.43) in the London LACKABO cohort to 1.30 (95%CI 1.13,1.49) in the English CRISIS cohort.
Outcomes in CKD patients attending outpatient nephrology clinics varied markedly across European regions. Although eGFR decline showed minor variation, the most variation was observed in CKD mortality. Our results suggest that different healthcare organization systems are potentially associated with differences in outcome of CKD patients within Europe. These results can be used by policy makers to plan resources on a regional, national and European level
KRAS-regulated glutamine metabolism requires UCP2-mediated aspartate transport to support pancreatic cancer growth
The oncogenic KRAS mutation has a critical role in the initiation of human pancreatic ductal adenocarcinoma (PDAC) since it rewires glutamine metabolism to increase reduced nicotinamide adenine dinucleotide phosphate (NADPH) production, balancing cellular redox homeostasis with macromolecular synthesis1,2. Mitochondrial glutamine-derived aspartate must be transported into the cytosol to generate metabolic precursors for NADPH production2. The mitochondrial transporter responsible for this aspartate efflux has remained elusive. Here, we show that mitochondrial uncoupling protein 2 (UCP2) catalyses this transport and promotes tumour growth. UCP2-silenced KRASmut cell lines display decreased glutaminolysis, lower NADPH/NADP+ and glutathione/glutathione disulfide ratios and higher reactive oxygen species levels compared to wild-type counterparts. UCP2 silencing reduces glutaminolysis also in KRASWT PDAC cells but does not affect their redox homeostasis or proliferation rates. In vitro and in vivo, UCP2 silencing strongly suppresses KRASmut PDAC cell growth. Collectively, these results demonstrate that UCP2 plays a vital role in PDAC, since its aspartate transport activity connects the mitochondrial and cytosolic reactions necessary for KRASmut rewired glutamine metabolism2, and thus it should be considered a key metabolic target for the treatment of this refractory tumour
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