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1.
Preprint in English | medRxiv | ID: ppmedrxiv-21261992

ABSTRACT

IntroductionAfter emerging the global pandemic of SARS-CoV2 some preliminary studies demonstrated the efficacy of antiviral treatments. But shortly thereafter, inconsistencies in the results of further clinical trials raised doubts on the efficacy of these agents. In this study, we aimed to evaluate the effect of Remdesivir on hospitalized COVID-19 patients outcomes. Material and methodsThis study was an open-label, single-armed, clinical trial on hospitalized patients diagnosed with COVID-19 who had progressive respiratory symptoms despite receiving standard care. All patients received Remdesivir and their characteristics, outcomes, time of treatment initiation, and respiratory support stages during hospitalization were registered and followed up for 14 days. Results145 patients with the mean age of 52.89 {+/-} 1.12 years enrolled in this study, 38 (26.2%) died at the end of 14 days period. The mean time interval from the onset of the symptoms to antiviral treatment was 10.63{+/-}0.56 days. Thirty deceased patients (78.9%) were men, showing 2.8 times higher mortality chance compared to women (ORadj=2.77; 95%CI=1.08-7.09). The type of respiratory support on the first day of treatment initiation showed a significantly lower mortality chance in patients receiving O2 only than those who needed non-invasive and/or mechanical ventilation (ORadj=3.91; 95%CI=1.64-9.32). The start time (early vs late administration) and duration (less or more than 7 days) of antiviral treatment had no statistically significant association with mortality or ventilation escalation among the patients (p-value > 0.05). ConclusionIn this study, we showed that Remdesivir probably is not effective on the outcome of hospitalized COVID-19 patients.

2.
Am J Cardiol ; 124(8): 1171-1178, 2019 10 15.
Article in English | MEDLINE | ID: mdl-31409450

ABSTRACT

The effect of normalization of serum testosterone levels with testosterone replacement therapy (TRT) in patients with a history of myocardial infarction (MI) is unknown. The objective of this study was to determine the incidence of recurrent MI and all-cause mortality in subjects with a history of MI and low total testosterone (TT) with and without TRT. We retrospectively examined 1,470 men with documented low TT levels and previous MI, categorized into Gp1: TRT with normalization of TT levels (n = 755) Gp2: TRT without normalization of TT levels (n = 542), and Gp3: no TRT (n = 173). The association of TRT with all-cause mortality and recurrent MI was compared using propensity score-weighted Cox proportional hazard models. All-cause mortality was lower in Gp1 versus Gp2 (hazard ratio [HR] 0.76, confidence interval [CI] 0.64 to 0.90, p = 0.002), and Gp1 versus Gp3 (HR 0.76, CI 0.60 to 0.98, p = 0.031). There was no significant difference in the risk of death between Gp2 versus Gp3 (HR 0.97, CI 0.76 to 1.24, p = 0.81). Adjusted regression analyses showed no significant differences in the risk of recurrent MI between groups (Gp1 vs Gp3, HR 0.79, CI 0.12 to 5.27, p = 0.8; Gp1 vs Gp2 HR 1.10, CI 0.25 to 4.77, p = 0.90; Gp2 vs Gp3 HR 0.58, CI 0.08 to 4.06, p = 0.58). In conclusion, in a large observational cohort of male veterans with previous MI, normalization of TT levels with TRT was associated with decreased all-cause mortality compared with those with non-normalized TT levels and the untreated group. Furthermore, in this high-risk population, TRT was not associated with an increased risk of recurrent MI.


Subject(s)
Hormone Replacement Therapy/adverse effects , Hypogonadism/drug therapy , Myocardial Infarction/epidemiology , Testosterone/blood , Aged , Biomarkers/blood , Cause of Death/trends , Follow-Up Studies , Humans , Hypogonadism/blood , Hypogonadism/complications , Incidence , Male , Middle Aged , Myocardial Infarction/blood , Myocardial Infarction/etiology , Prognosis , Propensity Score , Recurrence , Retrospective Studies , Risk Factors , Survival Rate/trends , Time Factors , United States/epidemiology
3.
Nano Lett ; 19(4): 2620-2626, 2019 04 10.
Article in English | MEDLINE | ID: mdl-30908917

ABSTRACT

Nanoscale field-effect transistors (FETs) represent a unique platform for real time, label-free transduction of biochemical signals with unprecedented sensitivity and spatiotemporal resolution, yet their translation toward practical biomedical applications remains challenging. Herein, we demonstrate the potential to overcome several key limitations of traditional FET sensors by exploiting bioactive hydrogels as the gate material. Spatially defined photopolymerization is utilized to achieve selective patterning of polyethylene glycol on top of individual graphene FET devices, through which multiple biospecific receptors can be independently encapsulated into the hydrogel gate. The hydrogel-mediated integration of penicillinase was demonstrated to effectively catalyze enzymatic reaction in the confined microenvironment, enabling real time, label-free detection of penicillin down to 0.2 mM. Multiplexed functionalization with penicillinase and acetylcholinesterase has been demonstrated to achieve highly specific sensing. In addition, the microenvironment created by the hydrogel gate has been shown to significantly reduce the nonspecific binding of nontarget molecules to graphene channels as well as preserve the encapsulated enzyme activity for at least one week, in comparison to free enzymes showing significant signal loss within one day. This general approach presents a new biointegration strategy and facilitates multiplex detection of bioanalytes on the same platform, which could underwrite new advances in healthcare research.


Subject(s)
Biosensing Techniques/methods , Nanotechnology/methods , Penicillinase/chemistry , Penicillins/isolation & purification , Biomedical Research/trends , Graphite/chemistry , Humans , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Penicillins/chemistry , Polyethylene Glycols/chemistry , Transistors, Electronic
4.
Sci Rep ; 6: 21858, 2016 Feb 24.
Article in English | MEDLINE | ID: mdl-26908346

ABSTRACT

Water decontamination and oil/water separation are principal motives in the surge to develop novel means for sustainability. In this prospect, supplying clean water for the ecosystems is as important as the recovery of the oil spills since the supplies are scarce. Inspired to design an engineering material which not only serves this purpose, but can also be altered for other applications to preserve natural resources, a facile template-free process is suggested to fabricate a superporous, superhydrophobic ultra-thin graphite sponge. Moreover, the process is designed to be inexpensive and scalable. The fabricated sponge can be used to clean up different types of oil, organic solvents, toxic and corrosive contaminants. This versatile microstructure can retain its functionality even when pulverized. The sponge is applicable for targeted sorption and collection due to its ferromagnetic properties. We hope that such a cost-effective process can be embraced and implemented widely.

5.
Medicine (Baltimore) ; 94(28): e1098, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26181543

ABSTRACT

This study aimed to evaluate dosimetric characteristics based on Monte Carlo (MC) simulations for a proposed beta emitter bioglass 188Re seed for internal radiotherapy applications. The bioactive glass seed has been developed using the sol-gel technique. The simulations were performed for the seed using MC radiation transport code to investigate the dosimetric factors recommended by the AAPM Task Group 60 (TG-60). Dose distributions due to the beta and photon radiation were predicted at different radial distances surrounding the source. The dose rate in water at the reference point was calculated to be 7.43 ±â€Š0.5 cGy/h/µCi. The dosimetric factors consisting of the reference point dose rate, D(r0,θ0), the radial dose function, g(r), the 2-dimensional anisotropy function, F(r,θ), the 1-dimensional anisotropy function, φan(r), and the R90 quantity were estimated and compared with several available beta-emitting sources. The element 188Re incorporated in bioactive glasses produced by the sol-gel technique provides a suitable solution for producing new materials for seed implants applied to brachytherapy applications in prostate and liver cancers treatment. Dose distribution of 188Re seed was greater isotropic than other commercially attainable encapsulated seeds, since it has no end weld to attenuate radiation. The beta radiation-emitting 188Re source provides high doses of local radiation to the tumor tissue and the short range of the beta particles limit damage to the adjacent normal tissue.


Subject(s)
Brachytherapy/instrumentation , Radioisotopes/administration & dosage , Rhenium/administration & dosage , Humans , Radiometry
6.
Sci Rep ; 5: 8781, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-25740298

ABSTRACT

Highly monodisperse porous silicon nanospheres (MPSSs) are synthesized via a simple and scalable hydrolysis process with subsequent surface-protected magnesiothermic reduction. The spherical nature of the MPSSs allows for a homogenous stress-strain distribution within the structure during lithiation and delithiation, which dramatically improves the electrochemical stability. To fully extract the real performance of the MPSSs, carbon nanotubes (CNTs) were added to enhance the electronic conductivity within the composite electrode structure, which has been verified to be an effective way to improve the rate and cycling performance of anodes based on nano-Si. The Li-ion battery (LIB) anodes based on MPSSs demonstrate a high reversible capacity of 3105 mAh g(-1). In particular, reversible Li storage capacities above 1500 mAh g(-1) were maintained after 500 cycles at a high rate of C/2. We believe this innovative approach for synthesizing porous Si-based LIB anode materials by using surface-protected magnesiothermic reduction can be readily applied to other types of SiOx nano/microstructures.

7.
Nanoscale ; 7(16): 7051-5, 2015 Apr 28.
Article in English | MEDLINE | ID: mdl-25712745

ABSTRACT

For the first time, SiO2-coated sulfur particles (SCSPs) were fabricated via a facile two-step wet chemical process for application as a novel lithium-sulfur cathode material. With the addition of mildly reduced graphene oxide (mrGO), SCSPs demonstrate even greater cycling stability, maintaining over 700 mA h g(-1) after the 50(th) cycle.

8.
Sci Rep ; 5: 8246, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25655007

ABSTRACT

The need for more energy dense and scalable Li-ion battery electrodes has become increasingly pressing with the ushering in of more powerful portable electronics and electric vehicles (EVs) requiring substantially longer range capabilities. Herein, we report on the first synthesis of nano-silicon paper electrodes synthesized via magnesiothermic reduction of electrospun SiO2 nanofiber paper produced by an in situ acid catalyzed polymerization of tetraethyl orthosilicate (TEOS) in-flight. Free-standing carbon-coated Si nanofiber binderless electrodes produce a capacity of 802 mAh g(-1) after 659 cycles with a Coulombic efficiency of 99.9%, which outperforms conventionally used slurry-prepared graphite anodes by over two times on an active material basis. Silicon nanofiber paper anodes offer a completely binder-free and Cu current collector-free approach to electrode fabrication with a silicon weight percent in excess of 80%. The absence of conductive powder additives, metallic current collectors, and polymer binders in addition to the high weight percent silicon all contribute to significantly increasing capacity at the cell level.

9.
Sci Rep ; 4: 5623, 2014 Jul 08.
Article in English | MEDLINE | ID: mdl-25001507

ABSTRACT

Herein, porous nano-silicon has been synthesized via a highly scalable heat scavenger-assisted magnesiothermic reduction of beach sand. This environmentally benign, highly abundant, and low cost SiO2 source allows for production of nano-silicon at the industry level with excellent electrochemical performance as an anode material for Li-ion batteries. The addition of NaCl, as an effective heat scavenger for the highly exothermic magnesium reduction process, promotes the formation of an interconnected 3D network of nano-silicon with a thickness of 8-10 nm. Carbon coated nano-silicon electrodes achieve remarkable electrochemical performance with a capacity of 1024 mAhg(-1) at 2 Ag(-1) after 1000 cycles.

10.
Small ; 10(16): 3389-96, 2014 Aug 27.
Article in English | MEDLINE | ID: mdl-24753292

ABSTRACT

In this work, we report the synthesis of an three-dimensional (3D) cone-shape CNT clusters (CCC) via chemical vapor deposition (CVD) with subsequent inductively coupled plasma (ICP) treatment. An innovative silicon decorated cone-shape CNT clusters (SCCC) is prepared by simply depositing amorphous silicon onto CCC via magnetron sputtering. The seamless connection between silicon decorated CNT cones and graphene facilitates the charge transfer in the system and suggests a binder-free technique of preparing lithium ion battery (LIB) anodes. Lithium ion batteries based on this novel 3D SCCC architecture demonstrates high reversible capacity of 1954 mAh g(-1) and excellent cycling stability (>1200 mAh g(-1) capacity with ≈ 100% coulombic efficiency after 230 cycles).

11.
Sci Rep ; 4: 4605, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24732245

ABSTRACT

Herein, SiO2 nanotubes have been fabricated via a facile two step hard-template growth method and evaluated as an anode for Li-ion batteries. SiO2 nanotubes exhibit a highly stable reversible capacity of 1266 mAhg(-1) after 100 cycles with negligible capacity fading. SiO2 NT anodes experience a capacity increase throughout the first 80 cycles through Si phase growth via SiO2 reduction. The hollow morphology of the SiO2 nanotubes accommodates the large volume expansion experienced by Si-based anodes during lithiation and promotes preservation of the solid electrolyte interphase layer. The thin walls of the SiO2 nanotubes allow for effective reduction in Li-ion diffusion path distance and, thus, afford a favorable rate cyclability. The high aspect ratio character of these nanotubes allow for a relatively scalable fabrication method of nanoscale SiO2-based anodes.

12.
Appl Radiat Isot ; 68(1): 211-3, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19762248

ABSTRACT

Monte Carlo calculations have been performed using the MCNP4C code for an iodine seed design. As the ADVANTAGE I-125, Model IAI-125 source is commercially available for interstitial brachytherapy treatment, dosimetric characteristics (dose rate constant, radial dose function and anisotropy function) of this source were theoretically determined following the updated AAPM task group 43 (TG-43U1) recommendations. The dose distribution around the seed was calculated with Monte Carlo simulation in liquid water. The Monte Carlo calculated dose rate constant of this source in water was found to be 0.986cGyh(-1)U(-1), with an approximate uncertainty of 0.4%. The obtained result has been compared with the previous study. Comparison of the calculated dose rate constant with the value presented by Meigooni et al. shows a very good agreement. Also the anisotropy function and the radial dose function for this source are graphically compared.


Subject(s)
Brachytherapy/methods , Iodine Radioisotopes/therapeutic use , Radiotherapy Dosage , Anisotropy , Monte Carlo Method
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