335 research outputs found
In Cardiac Patients β-Blockers Attenuate the Decrease in Work Rate during Exercise at a Constant Submaximal Heart Rate
Purpose Exercise prescription based on fixed heart rate (HR) values is not associated with a specific work rate (WR) during prolonged exercise. This phenomenon has never been evaluated in cardiac patients and might be associated with a slow component of HR kinetics and β-adrenergic activity. The aims were to quantify, in cardiac patients, the WR decrease at a fixed HR and to test if it would be attenuated by β-blockers. Methods Seventeen patients with coronary artery disease in stable conditions (69 ± 9 yr) were divided into two groups according to the presence (BB) or absence (no-BB) of a therapy with β-blockers, and performed on a cycle ergometer: An incremental exercise (INCR) and a 15-min "HRCLAMPED"exercise, in which WR was continuously adjusted to maintain a constant HR, corresponding to the gas exchange threshold +15%. HR was determined by the ECG signal, and pulmonary gas exchange was assessed breath-by-breath. Results During INCR, HRpeak was lower in BB versus no-BB (P < 0.05), whereas no differences were observed for other variables. During HRCLAMPED, the decrease in WR needed to maintain HR constant was less pronounced in BB versus no-BB (-16% ± 10% vs -27 ± 10, P = 0.04) and was accompanied by a decreased VO2 only in no-BB (-13% ± 6%, P < 0.001). Conclusions The decrease in WR during a 15-min exercise at a fixed HR (slightly higher than that at gas exchange threshold) was attenuated in BB, suggesting a potential role by β-adrenergic stimulation. The phenomenon may represent, also in this population, a sign of impaired exercise tolerance and interferes with aerobic exercise prescription
Predicting candidemia in internal medicine departments: are we chasing the Holy Grail?
Candidemia is a challenging clinical condition with high rates of morbidity and mortality.1 Key requirements for its prompt management include early identification and timely initiation of appropriate systemic antifungal therapy, consistently reported as a major determinant of survival. However, the diagnosis of candidemia can be challenging and is often delayed as there are no specific clinical signs, blood cultures have low sensitivity, and detection of fungal blood cultures takes a long time. In addition, there is evidence that a significant percentage of such infections occurs in patients admitted to internal medicine departments. This is not particularly surprising given the advanced age of many inpatients at internal medicine departments and multiple complex comorbidities. Moreover, related therapies and healthcare system contacts often involve the use of central venous catheters and other indwelling devices, potentially entailing high risk of candidemia.2 Therefore, optimization of the diagnostic and therapeutic approach is an important and still unfulfilled need for the management of candidemia in internal medicine department
Hybrid membrane distillation reverse electrodialysis configuration for water and energy recovery from human urine: an opportunity for off-grid decentralised sanitation
The integration of membrane distillation with reverse electrodialysis has been investigated as a sustainable sanitation solution to provide clean water and electrical power from urine and waste heat. Reverse electrodialysis was integrated to provide the partial remixing of the concentrate (urine) and diluate (permeate) produced from the membrane distillation of urine. Broadly comparable power densities to those of a model salt solution (sodium chloride) were determined during evaluation of the individual and combined contribution of the various monovalent and multivalent inorganic and organic salt constituents in urine. Power densities were improved through raising feed-side temperature and increasing concentration in the concentrate, without observation of limiting behaviour imposed by non-ideal salt and water transport. A further unique contribution of this application is the limited volume of salt concentrate available, which demanded brine recycling to maximise energy recovery analogous to a battery, operating in a ‘state of charge’. During recycle, around 47% of the Gibbs free energy was recoverable with up to 80% of the energy extractable before the concentration difference between the two solutions was halfway towards equilibrium which implies that energy recovery can be optimised with limited effect on permeate quality. This study has provided the first successful demonstration of an integrated MD-RED system for energy recovery from a limited resource, and evidences that the recovered power is sufficient to operate a range of low current fluid pumping technologies that could help deliver off-grid sanitation and clean water recovery at single household scale
How European Research Projects Can Support Vaccination Strategies: The Case of the ORCHESTRA Project for SARS-CoV-2
ORCHESTRA (“Connecting European Cohorts to Increase Common and Effective Response To SARS-CoV-2 Pandemic”) is an EU-funded project which aims to help rapidly advance the knowledge related to the prevention of the SARS-CoV-2 infection and the management of COVID-19 and its long-term sequelae. Here, we describe the early results of this project, focusing on the strengths of multiple, international, historical and prospective cohort studies and highlighting those results which are of potential relevance for vaccination strategies, such as the necessity of a vaccine booster dose after a primary vaccination course in hematologic cancer patients and in solid organ transplant recipients to elicit a higher antibody titer, and the protective effect of vaccination on severe COVID-19 clinical manifestation and on the emergence of post-COVID-19 conditions. Valuable data regarding epidemiological variations, risk factors of SARS-CoV-2 infection and its sequelae, and vaccination efficacy in different subpopulations can support further defining public health vaccination policies
Symphytum Species: A Comprehensive Review on Chemical Composition, Food Applications and Phytopharmacology
Symphytum species belongs to the Boraginaceae family and have been used for centuries for
bone breakages, sprains and rheumatism, liver problems, gastritis, ulcers, skin problems, joint pain
and contusions, wounds, gout, hematomas and thrombophlebitis. Considering the innumerable
potentialities of the Symphytum species and their widespread use in the world, it is extremely
important to provide data compiling the available literature to identify the areas of intense research
and the main gaps in order to design future studies. The present review aims at summarizing the
main data on the therapeutic indications of the Symphytum species based on the current evidence,
also emphasizing data on both the e cacy and adverse e ects. The present review was carried
out by consulting PubMed (Medline), Web of Science, Embase, Scopus, Cochrane Database, Science
Direct and Google Scholar (as a search engine) databases to retrieve the most updated articles on this
topic. All articles were carefully analyzed by the authors to assess their strengths and weaknesses,
and to select the most useful ones for the purpose of review, prioritizing articles published from 1956
to 2018. The pharmacological e ects of the Symphytum species are attributed to several chemical
compounds, among them allantoin, phenolic compounds, glycopeptides, polysaccharides and some
toxic pyrrolizidine alkaloids. Not less important to highlight are the risks associated with its use.
In fact, there is increasing consumption of over-the-counter drugs, which when associated with
conventional drugs can cause serious and even fatal adverse events. Although clinical trials sustain
the folk topical application of Symphytum species in musculoskeletal and blunt injuries, with minor
adverse e ects, its antimicrobial potency was still poorly investigated. Further studies are needed to
assess the antimicrobial spectrum of Symphytum species and to characterize the active molecules both
in vitro and in vivo
Comparison of the Electronic Structures and Energetics of Ferroelectric LiNbO3 and LiTaO3
This paper explains the origin of the ferroelectric instability in LiNbO3 and
LiTaO3 and compares the electronic structures and energetics of the two
materials.Comment: 31 pages, 11 Postscript figure
On-chip quantum interference between silicon photon-pair sources
Large-scale integrated quantum photonic technologies will require the on-chip
integration of identical photon sources with reconfigurable waveguide circuits.
Relatively complex quantum circuits have already been demonstrated, but few
studies acknowledge the pressing need to integrate photon sources and waveguide
circuits together on-chip. A key step towards such large-scale quantum
technologies is the integration of just two individual photon sources within a
waveguide circuit, and the demonstration of high-visibility quantum
interference between them. Here, we report a silicon-on-insulator device
combining two four-wave mixing sources, in an interferometer with a
reconfigurable phase shifter. We configure the device to create and manipulate
two-colour (non-degenerate) or same-colour (degenerate), path-entangled or
path-unentangled photon pairs. We observe up to 100.0+/-0.4% visibility quantum
interference on-chip, and up to 95+/-4% off-chip. Our device removes the need
for external photon sources, provides a path to increasing the complexity of
quantum photonic circuits, and is a first step towards fully-integrated quantum
technologies
The Role of Multidimensional Prognostic Index to Identify Hospitalized Older Adults with COVID-19 Who Can Benefit from Remdesivir Treatment: An Observational, Prospective, Multicenter Study
Background: Data regarding the importance of multidimensional frailty to guide clinical decision making for remdesivir use in older patients with coronavirus disease 2019 (COVID-19) are largely unexplored. Objective: The aim of this research was to evaluate if the Multidimensional Prognostic Index (MPI), a multidimensional frailty tool based on the Comprehensive Geriatric Assessment (CGA), may help physicians in identifying older hospitalized patients affected by COVID-19 who might benefit from the use of remdesivir. Methods: This was a multicenter, prospective study of older adults hospitalized for COVID-19 in 10 European hospitals, followed-up for 90 days after hospital discharge. A standardized CGA was performed at hospital admission and the MPI was calculated, with a final score ranging between 0 (lowest mortality risk) and 1 (highest mortality risk). We assessed survival with Cox regression, and the impact of remdesivir on mortality (overall and in hospital) with propensity score analysis, stratified by MPI = 0.50. Results: Among 496 older adults hospitalized for COVID-19 (mean age 80 years, female 59.9%), 140 (28.2% of patients) were treated with remdesivir. During the 90 days of follow-up, 175 deaths were reported, 115 in hospital. Remdesivir treatment significantly reduced the risk of overall mortality (hazard ratio [HR] 0.54, 95% confidence interval CI 0.35–0.83 in the propensity score analysis) in the sample as whole. Stratifying the population, based on MPI score, the effect was observed only in less frail participants (HR 0.47, 95% CI 0.22–0.96 in propensity score analysis), but not in frailer subjects. In-hospital mortality was not influenced by remdesivir use. Conclusions: MPI could help to identify less frail older adults hospitalized for COVID-19 who could benefit more from remdesivir treatment in terms of long-term survival
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