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1.
Regen Ther ; 27: 464-481, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38745840

RESUMO

Stem cells (SCs) play a crucial role in tissue repair, regeneration, and maintaining physiological homeostasis. Exercise mobilizes and enhances the function of SCs. This review examines the effects of acute and chronic aerobic and resistance exercise on the population of SCs in healthy and diseased individuals across different age groups. Both acute intense exercise and moderate regular training increase circulating precursor cells CD34+ and, in particular, the subset of angiogenic progenitor cells (APCs) CD34+/KDR+. Conversely, chronic exercise training has conflicting effects on circulating CD34+ cells and their function, which are likely influenced by exercise dosage, the health status of the participants, and the methodologies employed. While acute activity promotes transient mobilization, regular exercise often leads to an increased number of progenitors and more sustainable functionality. Short interventions lasting 10-21 days mobilize CD34+/KDR + APCs in sedentary elderly individuals, indicating the inherent capacity of the body to rapidly activate tissue-reparative SCs during activity. However, further investigation is needed to determine the optimal exercise regimens for enhancing SC mobilization, elucidating the underlying mechanisms, and establishing functional benefits for health and disease prevention. Current evidence supports the integration of intense exercise with chronic training in exercise protocols aimed at activating the inherent regenerative potential through SC mobilization. The physical activity promotes endogenous repair processes, and research on exercise protocols that effectively mobilize SCs can provide innovative guidelines designed for lifelong tissue regeneration. An artificial neural network (ANN) was developed to estimate the effects of modifying elderly individuals and implementing chronic resistance exercise on stem cell mobilization and its impact on individuals and exercise. The network's predictions were validated using linear regression and found to be acceptable compared to experimental results.

3.
J Mol Liq ; 341: 117430, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34483415

RESUMO

The coronavirus pandemic is caused by intense acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Identifying the atomic structure of this virus can lead to the treatment of related diseases in medical cases. In the current computational study, the atomic evolution of the coronavirus in an aqueous environment using the Molecular Dynamics (MD) approach is explained. The virus behaviors by reporting the physical attributes such as total energy, temperature, potential energy, interaction energy, volume, entropy, and radius of gyration of the modeled virus are reported. The MD results indicated the atomic stability of the simulated virus significantly reduced after 25.33 ns. Furthermore, the volume of simulated virus changes from 182397 Å3 to 372589 Å3 after t = 30 ns. This result shows the atomic interaction between various atoms in coronavirus structure decreases in the vicinity of H2O molecules. Numerically, the interaction energy between virus and aqueous environment converges to -12387 eV and -251 eV values in the initial and final time steps of the MD study procedure, respectively.

4.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-441024

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation that have a major impact on many diseases and provides an exciting avenue towards antiviral therapeutics. From patient transcriptomic data, we have discovered a circulating miRNA, miR-2392, that is directly involved with SARS-CoV-2 machinery during host infection. Specifically, we show that miR-2392 is key in driving downstream suppression of mitochondrial gene expression, increasing inflammation, glycolysis, and hypoxia as well as promoting many symptoms associated with COVID-19 infection. We demonstrate miR-2392 is present in the blood and urine of COVID-19 positive patients, but not detected in COVID-19 negative patients. These findings indicate the potential for developing a novel, minimally invasive, COVID-19 detection method. Lastly, using in vitro human and in vivo hamster models, we have developed a novel miRNA-based antiviral therapeutic that targets miR-2392, significantly reduces SARS-CoV-2 viability in hamsters and may potentially inhibit a COVID-19 disease state in humans.

5.
Chem Rec ; 18(2): 165-229, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28745452

RESUMO

The carbon-carbon and carbon-heteroatom bonds catalytic formation is among the most significant reactions in organic synthesis which extensively applied for synthesis of natural products, heterocycles, dendrimers, biologically active molecules and useful compounds. This review provides the latest advances in the preparation of graphene supported metal nanoparticles and their application in the catalytic formation of both carbon-carbon (C-C) and carbon-heteroatom (C-X) bonds including the Suzuki, Heck, Hiyama, Ullmann, Buchwald and Sonogashira coupling reactions. Numerous examples are given concerning the use of these catalysts in C-C and C-X coupling reactions along with the reliable and simple preparation methods of these catalysts, their characterization and catalytic properties and also the recycling possibilities.

6.
J Colloid Interface Sci ; 497: 1-13, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28260670

RESUMO

In this work, the Ag/Fe3O4 nanocomposite was prepared by Euphorbia peplus Linn (L.) leaf extract as a suitable reducing source and stabilizing agent. The green synthesized nanocomposite was characterized using X-ray diffraction analysis (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) images, energy-dispersive X-ray spectroscopy (EDS) and FT-IR spectroscopy. TEM analysis of Ag/Fe3O4 nanocomposite showed the spherical shape nanoparticles (NPs) with an average size of 5-10nm. The Ag/Fe3O4 nanocomposite then was used as a magnetically recoverable catalyst for the [2+3] cycloaddition of arylcyanamides and sodium azide in high yields and short reaction times without formation of hydrazoic acid (HN3). Also it can be easily recovered via applying of external magnetic field and reused several times without significant loss of activity.


Assuntos
Euphorbia/química , Química Verde , Nanocompostos/química , Extratos Vegetais/química , Folhas de Planta/química , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
J Colloid Interface Sci ; 462: 272-9, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26469545

RESUMO

This work reports a facile and green synthesis of Ag/TiO2 nanocomposite by extract of leaves of Euphorbia heterophylla without any stabilizer or surfactant. The green synthesized Ag/TiO2 nanocomposite was characterized by field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDS), fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction analysis (XRD) and UV-vis. The Ag/TiO2 nanocomposite was found to be effective catalyst for reduction of various dyes, such as 4-nitrophenol (4-NP), Methyl orange (MO), Congo red (CR) and Methylene blue (MB) in the presence of NaBH4 in water at room temperature. Catalysis reactions were monitored by employing UV-vis spectroscopy. Catalysis reactions followed pseudo-first order rate equation. The catalyst can be recovered and reused several times without significant loss of its catalytic activity.


Assuntos
Corantes/química , Euphorbia/química , Nanocompostos/química , Folhas de Planta/química , Prata/química , Titânio/química , Água/química , Catálise , Oxirredução , Tamanho da Partícula , Extratos Vegetais/química , Propriedades de Superfície
8.
J Colloid Interface Sci ; 462: 243-51, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26462089

RESUMO

For the first time the extract of the plant of Euphorbia granulate was used to green synthesis of Pd nanoparticles (NPs) as a heterogeneous catalyst for the phosphine-free Suzuki-Miyaura coupling reaction at room temperature. This method is a facile and eco-friendly way in organic synthesis using the plant extract as biomedia, bioreductant and capping ligand which considerably stabilizes the surface of Pd NPs. The presence of flavonoid and phenolics acids in the extract could be responsible for the reduction of Pd(2+) ions and formation of the corresponding Pd NPs.


Assuntos
Euphorbia/química , Nanopartículas Metálicas/química , Paládio/química , Extratos Vegetais/química , Folhas de Planta/química , Catálise , Euphorbia/metabolismo , Paládio/metabolismo , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Propriedades de Superfície
9.
J Colloid Interface Sci ; 459: 183-188, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26291574

RESUMO

CuO nanoparticles (NPs) were prepared by Anthemis nobilis flowers extract as a reducing and stabilizing agent and employed in catalyzing an aldehyde-amine-alkyne coupling reaction. The synthesized CuO NPs was characterized by SEM, EDS, XRD, FT-IR and UV-visible techniques. A diverse range of propargylamines were obtained in a good to high yield. Furthermore, the separation and reuse of CuO NPs was very simple, effective and economical.


Assuntos
Chamaemelum/química , Cobre/química , Flores/química , Nanopartículas/química , Propilaminas/química , Propilaminas/síntese química , Catálise
10.
J Colloid Interface Sci ; 450: 374-380, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25854504

RESUMO

During this study, we report the green synthesis of silver nanoparticles (Ag NPs) using Euphorbia helioscopia Linn leaf extract for the synthesis of propargylamines. Also, the structural and optical properties are studied. The synthesized nanoparticles are characterized by TEM, XRD, FT-IR and UV-visible techniques. UV-visible studies show an absorption band at 440 nm due to surface plasmon resonance (SPR) of the silver nanoparticles. Furthermore, the catalyst exhibits high catalytic activity, superior cycling stability and excellent substrate applicability.


Assuntos
Euphorbia/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Folhas de Planta/química , Prata/química
11.
Chromatographia ; 72(5-6): 523-533, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20835381

RESUMO

High resolution gas chromatographic relative retention time (HRGC-RRT) models were developed to predict relative retention times of the 209 individual polychlorinated biphenyls (PCBs) congeners. To estimate and predict the HRGC-RRT values of all PCBs on 18 different stationary phases, a multiple linear regression equation of the form RRT = a(o) + a(1) (no. o-Cl) + a(2) (no. m-Cl) + a(3) (no. p-Cl) + a(4) (V(M) or S(M)) was used. Molecular descriptors in the models included the number of ortho-, meta-, and para-chlorine substituents (no. o-Cl, m-Cl and p-Cl, respectively), the semi-empirically calculated molecular volume (V(M)), and the molecular surface area (S(M)). By means of the final variable selection method, four optimal semi-empirical descriptors were selected to develop a QSRR model for the prediction of RRT in PCBs with a correlation coefficient between 0.9272 and 0.9928 and a leave-one-out cross-validation correlation coefficient between 0.9230 and 0.9924 on each stationary phase. The root mean squares errors over different 18 stationary phases are within the range of 0.0108-0.0335. The accuracy of all the developed models were investigated using cross-validation leave-one-out (LOO), Y-randomization, external validation through an odd-even number and division of the entire data set into training and test sets. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1365/s10337-010-1696-5) contains supplementary material, which is available to authorized users.

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