The aim of this study was to analyze the mediation role of cardiorespiratory fitness and waist circumference in the association between muscular strength and cardiometabolic risk. A cross‐sectional ...study involved first‐year college students (n = 370) from a Spanish public university was performed. We measured weight, height, waist circumference, blood pressure, biochemical variables, maximum handgrip strength assessment, and cardiorespiratory fitness. We calculated handgrip dynamometry/weight and a previously validated cardiometabolic risk index. Analysis of covariance models was conducted to test differences in cardiometabolic risk values across muscular strength, cardiorespiratory fitness, and waist circumference categories, controlling for confounders. Hayes’ PROCESS macro was used for the multiple mediation analysis. The relationship between muscular strength and cardiometabolic risk did not remain significant (c′ = 1.76 1.4; P > .05) in a multiple serial bootstrapped mediation model including cardiorespiratory fitness and waist circumference as mediators when controlling for age and sex. According to the indirect effect, the significant paths in the model mediating this relationship between muscular strength and cardiometabolic risk index were as follows: muscular strength → waist circumference → cardiometabolic risk index (−4.899; 95% CI: −6.690; −3.450) and muscular strength → cardiorespiratory fitness → waist circumference → cardiometabolic risk index (−0.720; 95% CI: −1.316; −0.360). Both cardiorespiratory fitness and waist circumference mediate the association between muscular strength and cardiometabolic risk in young adults. Thus, our results place cardiorespiratory fitness and waist circumference as the main targets of physical activity programmes aimed at preventing cardiometabolic diseases.
In this paper we present the results of the radio light curve and X-ray observations of broad-lined Type Ic (Ic-BL) SN 2007bg. The light curve shows three distinct phases of spectral and temporal ...evolution, implying that the supernova (SN) shock likely encountered at least three different circumstellar medium regimes. We interpret this as the progenitor of SN 2007bg having at least two distinct mass-loss episodes (i.e. phases 1 and 3) during its final stages of evolution, yielding a highly stratified circumstellar medium. Modelling the phase 1 light curve as a freely expanding, synchrotron-emitting shell, self-absorbed by its own radiating electrons, requires a progenitor mass-loss rate of
M yr−1 for the last t ∼ 20(v
w/1000 km s−1) yr before explosion and a total energy of the radio-emitting ejecta of E 1 × 1048 erg 10 d after explosion. This places SN 2007bg among the most energetic Type Ib/c events. We interpret the second phase as a sparser 'gap' region between the two winds stages. Phase 3 shows a second absorption turn-on before rising to a peak luminosity 2.6 times higher than in phase 1. Assuming this luminosity jump is due to a circumstellar medium density enhancement from a faster previous mass-loss episode, we estimate that the phase 3 mass-loss rate could be as high as
M yr−1. The phase 3 wind would have transitioned directly into the phase 1 wind for a wind speed difference of 2. In summary, the radio light curve provides robust evidence for dramatic global changes in at least some Ic-BL progenitors just prior (∼10-1000 yr) to explosion. The observed luminosity of this SN is the highest observed for a non-gamma-ray-burst Ic-BL SN, reaching L
8.46 GHz 1 × 1029 erg Hz−1 s−1, ∼567 d after explosion.
ABSTRACT
We present photometric and spectroscopic observations of the unusual Type Ia supernova ASASSN-18tb, including a series of Southern African Large Telescope spectra obtained over the course of ...nearly six months and the first observations of a supernova by the Transiting Exoplanet Survey Satellite. We confirm a previous observation by Kollmeier et al. showing that ASASSN-18tb is the first relatively normal Type Ia supernova to exhibit clear broad (∼1000 km s−1) H α emission in its nebular-phase spectra. We find that this event is best explained as a sub-Chandrasekhar mass explosion producing $M_{\mathrm{ Ni}} \approx 0.3\,\, \rm {M}_\odot$. Despite the strong H α signature at late times, we find that the early rise of the supernova shows no evidence for deviations from a single-component power-law and is best fit with a moderately shallow power law of index 1.69 ± 0.04. We find that the H α luminosity remains approximately constant after its initial detection at phase +37 d, and that the H α velocity evolution does not trace that of the Fe iii λ4660 emission. These suggest that the H α emission arises from a circumstellar medium (CSM) rather than swept-up material from a non-degenerate companion. However, ASASSN-18tb is strikingly different from other known CSM-interacting Type Ia supernovae in a number of significant ways. Those objects typically show an H α luminosity two orders of magnitude higher than what is seen in ASASSN-18tb, pushing them away from the empirical light-curve relations that define ‘normal’ Type Ia supernovae. Conversely, ASASSN-18tb exhibits a fairly typical light curve and luminosity for an underluminous or transitional SN Ia, with MR ≈ −18.1 mag. Moreover, ASASSN-18tb is the only SN Ia showing H α from CSM interaction to be discovered in an early-type galaxy.
Serum Sclerostin in Alcoholics: A Pilot Study GONZALEZ-REIMERS, E; MARTIN-GONZALEZ, C; DE LA VEGA-PRIETO, M. J ...
Alcohol and alcoholism (Oxford),
05/2013, Letnik:
48, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Sclerostin is an endogenous inhibitor of the Wnt/β-catenin pathway secreted by osteocytes, which inhibits osteoblast function, differentiation and survival. As a consequence, sclerostin tends to ...decrease bone mass. Alcoholics frequently present osteoporosis, mainly due to decreased bone synthesis. The behaviour of sclerostin in these patients is unknown. The aim of this work was to analyse the relationship between serum sclerostin levels and bone mineral density (BMD), ethanol consumption, nutritional status, liver function derangement and biomarkers of bone homeostasis in alcoholic patients.
We included 31 alcoholic patients, of whom 11 were infected with Hepatitis C virus (HCV) and 7 age and sex-matched controls. All underwent densitometry, and serum sclerostin, osteocalcin, collagen telopeptide, parathyroid hormone (PTH), vitamin D, cortisol and testosterone were determined.
Sclerostin levels were significantly higher in patients (30.95 ± 18.91 pmol/l) than controls (t = 4.4; P < 0.001), especially in non-HCV patients; they showed an inverse correlation with osteocalcin, prothrombin activity and serum albumin, and a direct correlation with bilirubin and telopeptide, but not with BMD, nutritional status or ethanol intake.
Serum sclerostin was raised in alcoholic patients, and it correlated with decreased markers of bone synthesis and increased markers of bone breakdown. The elevation in sclerostin levels was clearly related with liver function, but not with ethanol intake, nutritional status or concomitant HCV infection.
We present late-time Hubble and Spitzer Space Telescope (SST) imaging of SN 2008S and NGC 300 2008OT-1, the prototypes of a common class of stellar transients whose true nature is debated. Both ...objects are still fading and are now >15 times fainter than their progenitors in the mid-IR and are undetected in the optical and near-IR. Data from the Large Binocular Telescope and Magellan show that neither source has been variable in the optical since fading in 2010. We present models of surviving sources obscured by dusty shells or winds and find that extreme dust models are needed for surviving stars to be successfully hidden by dust, which suggests that these transients may be genuine, but low-energy, supernova explosions. Though SN 2008S is not detected in Chandra X-Ray Observatory data taken in 2012, the flux limits allow the fading IR source to be powered solely by the shock interaction of ejecta with the circumstellar medium if the shock velocity at the time of the observation was 20 per cent slower than estimated from emission line widths while the transient was still optically bright. Continued SST monitoring and 10-20 mu m observations with James Webb Space Telescope can resolve any remaining ambiguities.
Strongly out-of-equilibrium regimes in magnetic nanostructures exhibit novel properties, linked to the nonlinear nature of magnetization dynamics, which are of great fundamental and practical ...interest. Here, we demonstrate that ferromagnetic resonance driven by microwave magnetic fields can occur with substantial spatial coherency at an unprecedented large angle of magnetization precessions, which is normally prevented by the onset of spin-wave instabilities and magnetization turbulent dynamics. Our results show that this limitation can be overcome in nanomagnets, where the geometric confinement drastically reduces the density of spin-wave modes. When the obtained deeply nonlinear ferromagnetic resonance regime is perturbed, the magnetization undergoes eigenoscillations around the steady state due to torques tending to restore the stable large-angle periodic trajectory. These eigenoscillations are substantially different from the usual spin-wave modes around the ground state because their existence is connected to the presence of a large coherent precession. They are experimentally investigated by a new spectroscopic technique based on the application of a second microwave excitation field that is tuned to resonantly drive them. This two-tone spectroscopy enables us to show that they consist in slow coherent magnetization nutations around the large-angle steady precession, whose frequencies are set by the balance of restoring torques. Our experimental findings are well accounted for by an analytical model derived for systems with uniaxial symmetry. They also provide a new means for controlling highly nonlinear magnetization dynamics in nanostructures, opening interesting applicative opportunities in the context of magnetic nanotechnologies.
Myocardial infarction is one of the major causes of morbidity and mortality worldwide. Current treatments can relieve the symptoms of myocardial ischemia but cannot repair the necrotic myocardial ...tissue. Novel therapeutic strategies based on cellular therapy, extracellular vesicles, non-coding RNAs and growth factors have been designed to restore cardiac function while inducing cardiomyocyte cycle re-entry, ensuring angiogenesis and cardioprotection, and preventing ventricular remodeling. However, they face low stability, cell engraftment issues or enzymatic degradation in vivo, and it is thus essential to combine them with biomaterial-based delivery systems. Microcarriers, nanocarriers, cardiac patches and injectable hydrogels have yielded promising results in preclinical studies, some of which are currently being tested in clinical trials. In this review, we cover the recent advances made in cellular and acellular therapies used for cardiac repair after MI. We present current trends in cardiac tissue engineering related to the use of microcarriers, nanocarriers, cardiac patches and injectable hydrogels as biomaterial-based delivery systems for biologics. Finally, we discuss some of the most crucial aspects that should be addressed in order to advance towards the clinical translation of cardiac tissue engineering approaches.
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With a very poor prognosis and no clear etiology, glioma is the most aggressive cancer in the brain. Thanks to its versatility, nanomedicine is a promising option to overcome the ...limitations on chemotherapy imposed by the blood brain barrier (BBB). The objective of this paper was to obtain monitored tumor-targeted therapeutic nanoparticles (NPs). To that end, theranostic surfactant-coated polymer poly-Lactic-co-Glycolic Acid (PLGA) nanoplatform encapsulating doxorubicin hydrochloride (DOX) and superparamagnetic iron oxide NPs (SPIONs) were developed. Different non-ionic surfactants known as BBB crossing enhancers (Tween 80, Brij-35, Pluronic F68 or Vitamin E-TPGS) were used to develop 4 types of theranostic nanoplatforms, which were characterized in terms of size and morphology by DLS, TEM and STEM-HAADF analyses. Moreover, the 3-month stability test, the therapeutic efficacy against different glioma cell lines (U87-MG, 9L/LacZ and patient derived-neuronal stem cells) and the Magnetic Resonance Imaging (MRI) relaxivity were studied. Results showed that the synthesised nanoplatforms were stable at 4 °C after their lyophilization, being that of paramount importance to ensure a long-term stability in a future in vivo application. Furthermore, the theranostic nanoplatforms were efficient in the in vitro treatment of glioma cells, proving to have imaging efficacy as MRI contrast agents. Our results show an efficient loading of drugs and good value of the relaxivity. Therefore, the efficient theranostic hybrid nanoplatform developed here could be used to perform MRI-guided delivery of hydrophobic drugs.
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