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1.
Biomed Mater Eng ; 35(3): 303-321, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517766

RESUMO

BACKGROUND: The clinical outcomes of bipolar radiofrequency (RF) lipolysis, a prevalent non-invasive fat reduction procedure, hinge on the delicate balance between effective lipolysis and patient safety, with skin overheating and subsequent tissue damage as primary concerns. OBJECTIVE: This study aimed to investigate a novel bipolar radiofrequency lipolysis technique, safeguarding the skin through an innovative PID temperature control algorithm. METHODS: Utilizing COMSOL Multiphysics simulation software, a two-dimensional fat and skin tissue model was established, simulating various PID temperature control schemes. The crux of the simulation involved a comparative analysis of different PID temperatures at 45 °C, 50 °C, and 55 °C and constant power strategies, assessing their implications on skin temperature. Concurrently, a custom bipolar radiofrequency lipolysis device was developed, with ex vivo experiments conducted using porcine tissue for empirical validation. RESULTS: The findings indicated that with PID settings of Kp = 7, Ki = 2, and Kd = 0, and skin temperature control at 45 °C or 50 °C, the innovative PID-based epidermal temperature control strategy successfully maintained the epidermal temperature within a safe range. This maintenance was achieved without compromising the effectiveness of RF lipolysis, significantly reducing the risk of thermal damage to the skin layers. CONCLUSION: Our research confirms the substantial practical utility of this advanced PID-based bipolar RF lipolysis technique in clinical aesthetic procedures, enhancing patient safety during adipose tissue ablation therapies.


Assuntos
Algoritmos , Lipólise , Temperatura Cutânea , Suínos , Animais , Tecido Adiposo , Humanos , Simulação por Computador , Pele/efeitos da radiação , Modelos Biológicos , Lipectomia/métodos , Lipectomia/instrumentação , Ablação por Radiofrequência/métodos
2.
Talanta ; 274: 125983, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537350

RESUMO

The utilization of deep eutectic solvents (DES) in sustainable extracting and separating of phytochemicals shows promising prospect. An exceptionally fast, eco-friendly, and sustainable approach was proposed for extracting bioactive compounds from Coptidis Rhizoma based on deep eutectic solvent-based ultrasound-assisted matrix solid phase dispersion (DES-UA-MSPD). Single-factor experiments and Box-Behnken design were utilized to explore the optimal extraction conditions. The analysis indicated that the acidic DES, especially betaine-acrylic acid (Bet-Aa 1:4 mol/mol) with 50% water content, was proved to be the most effective medium for the extraction of alkaloids (magnoflorine, groenlandicine, coptisine, epiberberine, berberine and palmatine) and organic acid (chlorogenic acid). With the parameters optimized, the total maximum extraction yield of alkaloids and organic acids reached 128.83 mg g-1 applying the optimal DES, which was 1.33-5.33 folds higher than conventional extraction solvents. Additionally, through microstructure analysis using scanning electron microscopy, density functional theory , and frontier molecular orbitals theory, a deeper understanding of the extraction principle was gained, and the molecular mechanism of DES synthesis and the interactions between target compounds were systematically elucidated. The sustainable and green potential of the DES-UA-MSPD method was demonstrated through Green Analytical Procedure Indexanalysis. The overall results of this investigation revealed that the proposed technology was a highly promising and sustainable alternative for effective extraction and quantification of natural products.


Assuntos
Alcaloides , Solventes Eutéticos Profundos , Alcaloides/análise , Alcaloides/química , Alcaloides/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Solventes Eutéticos Profundos/química , Ondas Ultrassônicas , Química Verde/métodos , Extração em Fase Sólida/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Coptis chinensis
3.
Small ; 19(38): e2302055, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37222116

RESUMO

Heteroatoms Fe, F co-doped NiO hollow spheres (Fe, F-NiO) are designed, which simultaneously integrate promoted thermodynamics by electronic structure modulation with boosted reaction kinetics by nano-architectonics. Benefiting from the electronic structure co-regulation of Ni sites by introducing Fe and F atoms in NiO , as the rate-determined step (RDS), the Gibbs free energy of OH* intermediates (ΔGOH* ) for Fe, F-NiO catalyst is significantly decreased to 1.87 eV for oxygen evolution reaction (OER) compared with pristine NiO (2.23 eV), which reduces the energy barrier and improves the reaction activity. Besides, densities of states (DOS) result verifies the bandgap of Fe, F-NiO(100) is significantly decreased compared with pristine NiO(100), which is beneficial to promote electrons transfer efficiency in electrochemical system. Profiting by the synergistic effect, the Fe, F-NiO hollow spheres only require the overpotential of 215 mV for OER at 10 mA cm-2 and extraordinary durability under alkaline condition. The assembled Fe, F-NiO||Fe-Ni2 P system only needs 1.51 V to reach 10 mA cm-2 , also exhibits outstanding electrocatalytic durability for continuous operation. More importantly, replacing the sluggish OER by advanced sulfion oxidation reaction (SOR) not only can realize the energy saving H2 production and toxic substances degradation, but also bring additional economic benefits.

4.
Life Sci ; 257: 118080, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653520

RESUMO

The COVID-19 pandemic raised by SARS-CoV-2 is a public health emergency. However, lack of antiviral drugs and vaccine against human coronaviruses demands a concerted approach to challenge the SARS-CoV-2 infection. Under limited resource and urgency, combinatorial computational approaches to identify the potential inhibitor from known drugs could be applied against risen COVID-19 pandemic. Thereof, this study attempted to purpose the potent inhibitors from the approved drug pool against SARS-CoV-2 main protease (Mpro). To circumvent the issue of lead compound from available drugs as antivirals, antibiotics with broad spectrum of viral activity, i.e. doxycycline, tetracycline, demeclocycline, and minocycline were chosen for molecular simulation analysis against native ligand N3 inhibitor in SARS-CoV-2 Mpro crystal structure. Molecular docking simulation predicted the docking score >-7 kcal/mol with significant intermolecular interaction at the catalytic dyad (His41 and Cys145) and other essential substrate binding residues of SARS-CoV-2 Mpro. The best ligand conformations were further studied for complex stability and intermolecular interaction profiling with respect to time under 100 ns classical molecular dynamics simulation, established the significant stability and interactions of selected antibiotics by comparison to N3 inhibitor. Based on combinatorial molecular simulation analysis, doxycycline and minocycline were selected as potent inhibitor against SARS-CoV-2 Mpro which can used in combinational therapy against SARS-CoV-2 infection.


Assuntos
Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Tetraciclinas/farmacologia , Antibacterianos , Antivirais/farmacologia , Sítios de Ligação/fisiologia , COVID-19 , Biologia Computacional/métodos , Infecções por Coronavirus/tratamento farmacológico , Bases de Dados Genéticas , Humanos , Ligantes , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Pandemias , Peptídeo Hidrolases/efeitos dos fármacos , Peptídeo Hidrolases/farmacologia , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2 , Proteínas não Estruturais Virais/antagonistas & inibidores
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