Τετάρτη, 18 Μαΐου 2016

PUSHing Core-collapse Supernovae to Explosions in Spherical Symmetry I: the Model and the Case of SN 1987A

We report on a method, PUSH, for artificially triggering core-collapse supernova explosions of massive stars in spherical symmetry. We explore basic explosion properties and calibrate PUSH to reproduce SN 1987A observables. Our simulations are based on the GR hydrodynamics code AGILE combined with the neutrino transport scheme isotropic diffusion source approximation for electron neutrinos and advanced spectral leakage for the heavy flavor neutrinos. To trigger explosions in the otherwise non-exploding simulations, the PUSH method increases the energy deposition in the gain region proportionally to the heavy flavor neutrino fluxes. We explore the progenitor range 18-21 ⊙ . Our studies reveal a distinction between high compactness (HC; compactness parameter {ξ }1.75\gt 0.45) and low compactness (LC; {ξ }1.75\lt 0.45) progenitor models, where LC models tend to explode earlier, with a lower explosion energy, and with a lower remnant mass. HC models are needed to obtain explosion energies around 1 Bethe, as observed for SN 1987A. However, all the models with sufficiently high explosion energy overproduce 56Ni and fallback is needed to reproduce the observed nucleosynthesis yields. 57-58Ni yields depend sensitively on the electron fraction and on the location of the mass cut with respect to the shell structure of the progenitor. We identify a progenitor and a suitable set of parameters that fit the explosion properties of SN 1987A assuming 0.1 ⊙ of fallback. We predict a neutron star with a gravitational mass of 1.50 ⊙ . We find correlations between explosion properties and the compactness of the progenitor model in the explored mass range. However, a more complete analysis will require exploring of a larger set of progenitors.

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Adipocytes Viability After Suction-Assisted Lipoplasty: Does the Technique Matter?

Abstract

Background

Suction-assisted lipoplasty (SAL; liposuction) is an established aesthetic procedure in plastic surgery. The main parameters differentiating one method of lipoplasty from another are safety, consistency of results, and other more technical parameters. Due to the recent popularity of lipotransfer, the quality of extracted fat has become a relevant parameter. We compare the viability of extracted adipocytes after dry SAL, hyper-tumescent PAL (power-assisted lipoplasty), and water-assisted lipoplasty (WAL).

Methods

We used fluorescent microscopy to differentiate viable from necrotic/apoptotic cells after liposuction using each of the mentioned methods.

Results

The ratio of living cells between the three methods was significantly different with dry liposuction yielding inferior ratios (p = 0.011). When omitting extreme results, we found that the body-jet technique (WAL) yielded higher ratios of living cells than the hyper-tumescent technique (p < 0.001). The total number of cells was highest in the hyper-tumescent method (p = 0.013).

Conclusions

Our results indicate that the hyper-tumescent technique yields the highest number of cells, whereas the body-jet technique yields the highest living cells ratio. The dry technique is clearly inferior to both.

No Level Assigned

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://ift.tt/18t7xNj.



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Tumori, fare sport abbassa il rischio. Non solo per i magri - Ladyblitz


Ladyblitz

Tumori, fare sport abbassa il rischio. Non solo per i magri
Ladyblitz
In particolare, correre, camminare o nuotare regolarmente diminuisce di oltre il 20% il rischio di ammalarsi di alcuni tumori come quello al fegato e al rene e di oltre il 40% di tumore all'esofago. A confermare l'importanza dell'allenamento aerobico ...

and more »


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The benefit of HH during the CPAP titration in the cool sleeping environment

Abstract

Purpose

Upper airway symptom associated with continuous positive airway pressure (CPAP) treatment is an important factor influencing CPAP adherence. There are conflicting data on the effect of a heated humidifier (HH) during CPAP titration for patients with obstructive sleep apnea hypopnea syndrome (OSAHS). This study investigated the effects of HH during CPAP titration in the cool sleeping environment.

Methods

Forty newly diagnosed OSAHS patients who received CPAP titration in the cool sleeping environment were randomly assigned to HH and non-HH groups. A questionnaire was used to evaluate upper airway symptoms, satisfaction with initial CPAP treatment, and willingness to further use CPAP. Some therapy parameters including leak, apnea hypopnea index (AHI) reduction, and optimal CPAP pressure level were analyzed. We compared these subjective and objective data between the two groups.

Results

In subjective sensation, the use of HH can alleviate upper airway symptoms associated with CPAP titration (P < 0.001). The HH group has benefit in satisfaction with initial CPAP treatment (P < 0.001) and further willingness to use CPAP (P < 0.01), although there were no significant differences in leak, AHI reduction, and optimal CPAP pressure between the two groups.

Conclusions

The use of HH is recommended during CPAP titration in the cool sleeping environment because of its benefit in the treatment of upper airway symptoms associated with CPAP therapy and improvement of the CPAP acceptance.



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Validation of a Hindi version of the Epworth Sleepiness Scale (ESS) at AIIMS, New Delhi in sleep-disordered breathing

Abstract

Purpose

The Epworth Sleepiness Scale (ESS) is one of the most widely used questionnaire for the assessment of excessive daytime sleepiness (EDS) in sleep-disordered breathing (SDB). This study was conducted to assess the validity of ESS in the Hindi language.

Methods

The Hindi version was developed by translation and back translation by independent translators. The English and Hindi versions were administered to 115 bilingual subjects who presented with symptoms of SDB, of whom 98 underwent a polysomnography at a tertiary care hospital in North India.

Results

The questionnaire had a high level of internal consistency as measured by Cronbach’s alpha (α = 0.84). There was no significant difference between the mean ESS scores of Hindi and English versions (11.65 ± 5.47 vs 11.70 ± 5.49, respectively; p = 0.80). The Hindi version of ESS showed a strong correlation with the English version (Spearman’s correlation ρ = 0.98 and weighted kappa = 0.94). Each of the 8 individual questions of Hindi ESS demonstrated a good agreement with the corresponding English version. The Hindi ESS score was significantly higher in subjects with OSA compared to those without OSA (12.67 ± 5.29 vs 7.76 ± 5.44, respectively; p = 0.002). However, there was no difference in ESS score between mild and moderate OSA or between moderate and severe OSA.

Conclusions

The Hindi version of the ESS showed a good internal consistency and a strong correlation with the English version and can be used in the Hindi-speaking population.



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The Roles of the Olivocerebellar Pathway in Motor Learning and Motor Control. A Consensus Paper

Abstract

For many decades, the predominant view in the cerebellar field has been that the olivocerebellar system’s primary function is to induce plasticity in the cerebellar cortex, specifically, at the parallel fiber-Purkinje cell synapse. However, it has also long been proposed that the olivocerebellar system participates directly in motor control by helping to shape ongoing motor commands being issued by the cerebellum. Evidence consistent with both hypotheses exists; however, they are often investigated as mutually exclusive alternatives. In contrast, here, we take the perspective that the olivocerebellar system can contribute to both the motor learning and motor control functions of the cerebellum and might also play a role in development. We then consider the potential problems and benefits of it having multiple functions. Moreover, we discuss how its distinctive characteristics (e.g., low firing rates, synchronization, and variable complex spike waveforms) make it more or less suitable for one or the other of these functions, and why having multiple functions makes sense from an evolutionary perspective. We did not attempt to reach a consensus on the specific role(s) the olivocerebellar system plays in different types of movements, as that will ultimately be determined experimentally; however, collectively, the various contributions highlight the flexibility of the olivocerebellar system, and thereby suggest that it has the potential to act in both the motor learning and motor control functions of the cerebellum.



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Alloplastic total temporomandibular joint replacements: do they perform like natural joints? Prospective cohort study with a historical control

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Publication date: Available online 19 May 2016
Source:International Journal of Oral and Maxillofacial Surgery
Author(s): A. Wojczyńska, C.S. Leiggener, M. Bredell, D.A. Ettlin, S. Erni, L.M. Gallo, V. Colombo
The aim of this study was to qualitatively and quantitatively describe the biomechanics of existing total alloplastic reconstructions of temporomandibular joints (TMJ). Fifteen patients with unilateral or bilateral TMJ total joint replacements and 15 healthy controls were evaluated via dynamic stereometry technology. This non-invasive method combines three-dimensional imaging of the subject's anatomy with jaw tracking. It provides an insight into the patient's jaw joint movements in real time and provides a quantitative evaluation. The patients were also evaluated clinically for jaw opening, protrusive and laterotrusive movements, pain, interference with eating, and satisfaction with the joint replacements. The qualitative assessment revealed that condyles of bilateral total joint replacements displayed similar basic motion patterns to those of unilateral prostheses. Quantitatively, mandibular movements of artificial joints during opening, protrusion, and laterotrusion were all significantly shorter than those of controls. A significantly restricted mandibular range of motion in replaced joints was also observed clinically. Fifty-three percent of patients suffered from chronic pain at rest and 67% reported reduced chewing function. Nonetheless, patients declared a high level of satisfaction with the replacement. This study shows that in order to gain a comprehensive understanding of complex therapeutic measures, a multidisciplinary approach is needed.



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Editorial Board

Publication date: July 2016
Source:Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1860, Issue 7





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Quercetin-3-O-rhamnoside from Euphorbia hirta protects against snake Venom induced toxicity

Publication date: July 2016
Source:Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1860, Issue 7
Author(s): Kadiyala Gopi, K. Anbarasu, Kadali Renu, S. Jayanthi, B.S. Vishwanath, Gurunathan Jayaraman
BackgroundThe plant Euphorbia hirta is widely used against snake envenomations in rural areas and it was proved to be effective in animal models. Therefore, the scientific validation of its phytoconstituents for their antiophidian activity is aimed in the present study.MethodsE. hirta extract was subjected to bioactivity guided fractionation and the fractions that inhibited different enzyme activities of Naja naja venom in vitro was structurally characterized using UV, FT-IR, LC–MS and NMR spectroscopy. Edema, hemorrhage and lethality inhibition activity of the compound were studied in mice model. In addition, molecular docking and molecular dynamic simulations were also performed in silico.ResultsThe bioactive fraction was identified as Quercetin-3-O-α-rhamnoside (QR, 448.38 Da). In vitro experiments indicated that protease, phospholipase-A2, hemolytic activity and hemorrhage inducing activity of the venom were inhibited completely at a ratio of 1:20 (venom: QR) w/w. At the same concentration, the edema ratio was drastically reduced from 187% to 107%. Significant inhibition (93%) of hyaluronidase activity was also observed at a slightly higher concentration of QR (1:50). Further, in in vivo analysis, QR significantly prolonged the survival time of mice injected with snake venom.ConclusionFor the first time Quercetin-3-O-α-rhamnoside, isolated from E. hirta, has been shown to exhibit anti-snake venom activity against Naja naja venom induced toxicity.General significanceExploring such multifunctional lead molecules with anti-venom activity would help in developing complementary medicine for snakebite treatments especially in rural areas where anti-snake venom is not readily available.



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An in vitro evaluation of epigallocatechin gallate (eGCG) as a biocompatible inhibitor of ricin toxin

Publication date: July 2016
Source:Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1860, Issue 7
Author(s): Paul D.R. Dyer, Arun K. Kotha, Alex S. Gollings, Susan A. Shorter, Thomas R. Shepherd, Marie W. Pettit, Bruce D. Alexander, Giulia T.M. Getti, Samer El-Daher, Les Baillie, Simon C.W. Richardson
The catechin, epigallocatechin gallate (eGCG), found in green tea, has inhibitory activity against a number of protein toxins and was investigated in relation to its impact upon ricin toxin (RT) in vitro. The IC50 for RT was 0.08±0.004ng/mL whereas the IC50 for RT+100μM eGCG was 3.02±0.572ng/mL, indicating that eGCG mediated a significant (p<0.0001) reduction in ricin toxicity. This experiment was repeated in the human macrophage cell line THP-1 and IC50 values were obtained for RT (0.54±0.024ng/mL) and RT+100μM eGCG (0.68±0.235ng/mL) again using 100μM eGCG and was significant (p=0.0013). The documented reduction in ricin toxicity mediated by eGCG was found to be eGCG concentration dependent, with 80 and 100μg/mL (i.e. 178 and 223μM respectively) of eGCG mediating a significant (p=0.0472 and 0.0232) reduction in ricin toxicity at 20 and 4ng/ml of RT in Vero and THP-1 cells (respectively). When viability was measured in THP-1 cells by propidium iodide exclusion (as opposed to the MTT assays used previously) 10ng/mL and 5ng/mL of RT was used. The addition of 1000μM and 100μM eGCG mediated a significant (p=0.0015 and <0.0001 respectively) reduction in ricin toxicity relative to an identical concentration of ricin with 1μg eGCG. Further, eGCG (100μM) was found to reduce the binding of RT B chain to lactose-conjugated Sepharose as well as significantly (p=0.0039) reduce the uptake of RT B chain in Vero cells. This data suggests that eGCG may provide a starting point to refine biocompatible substances that can reduce the lethality of ricin.



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Pulsed electrical stimulation benefits wound healing by activating skin fibroblasts through the TGFβ1/ERK/NF-κB axis

Publication date: July 2016
Source:Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1860, Issue 7
Author(s): Yongliang Wang, Mahmoud Rouabhia, Ze Zhang
BackgroundDermal fibroblasts activated by conductive polymer-mediated electrical stimulation (ES) have shown myofibroblast characteristics that favor wound healing. However, the signaling pathway related to this phenotype switch remains unclear, and the in vivo survival of the electrically activated cells has never been studied.MethodsPrimary human skin fibroblasts were exposed to pulsed-ES mediated through polypyrrole (PPy) coated fabrics. The expression of α-smooth muscle actin (α-SMA) and the signaling pathways were investigated by ELISA, Western blot and specific inhibition test, and immunocytochemistry staining as well as qRT-PCR analysis. In vivo implantation was performed in a mouse model to clarify the cell fate or contractile phenotype maintenance following ES stimulation.ResultsWe demonstrated the upregulation of TGFβ1 and phosph-ERK, and the NF-κB nuclear enrichment in the ES-activated cells. The ES-activated fibroblasts retained high level of α-smooth muscle actin expression even after prolonged subculture. Subcutaneous implantation for 15days revealed more human myofibroblasts in the experimental groups.ConclusionsThese findings demonstrate for the first time the involvement of the TGFβ1/ERK/NF-κB signaling pathway in ES-activated fibroblasts. The ES induced phenotype switch proves stable in subculture and in animal, pointing potential application in wound healing.General significanceReveal of how ES activates cells and the implication of ES activated cells in wound healing.



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Neurofilament networks: Salt-responsive hydrogels with sidearm-dependent phase behavior

Publication date: July 2016
Source:Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1860, Issue 7
Author(s): Joanna Deek, Peter J. Chung, Cyrus R. Safinya
BackgroundNeurofilaments (NFs) — the neuron-specific intermediate filament proteins — are assembled into 10nm wide filaments in a tightly controlled ratio of three different monomer types: NF-Low (NF-L), NF-Medium (NF-M), and NF-High (NF-H). Previous work on reconstituted bovine NF hydrogels has shown the dependence of network properties, including filament alignment and spacing, on the subunit composition.MethodsWe use polarized optical microscopy and SAXS to explore the full salt-dependent phase behavior of reconstituted bovine NF networks as a function of various binary and ternary subunit ratios.ResultsWe observe three salt-induced liquid crystalline phases: the liquid-ordered BG and NG phases, and the disordered IG phase. We note the emergent sidearm roles, particularly that of NF-H in driving the parallel to cross-filament transition, and the counter-role of NF-M in suppressing the IG phase.ConclusionsIn copolymers of NF-LH, NF-H shifts the IG to NG transition to nearer physiological salt concentrations, as compared to NF-M in copolymers of NF-LM. For ternary mixtures, the role of NF-H is modulated by the ratio of NF-M, where beneath 10wt.% NF-M, NF-H drives the transition to the disordered phase, and above which NF-H increases interfilament spacing.General significanceUnderstanding the role of individual subunits in regulating the network structure will enable us to understand the mechanisms that drive the dysfunction of these networks, as observed in diseased conditions.

Graphical abstract

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