Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Bioorg Chem ; 133: 106435, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36841049

RESUMO

Herein, we synthesized an affinity-based probe of myricanol (pMY) with a photo-affinity cross-linker to initiate a bioconjugation reaction, which was applied for target identification in live C2C12 myotubes. Pull-down of biotinylated pMY coupled with mass spectroscopy and Western blotting revealed that pMY can bind with nicotinamide phosphoribosyltransferase (Nampt), a rate-limiting enzyme in the nicotinamide adenine dinucleotide salvage pathway. Cellular thermal shift assay, drug affinity responsive target stability assay and recombinant protein labeling further validated the direct interaction between myricanol and Nampt. Myricanol did not affect the protein expression of Nampt, but enhanced its activity. Knock-down of Nampt totally abolished the promoting effect of myricanol on insulin-stimulated glucose uptake in C2C12 myotubes. Taken together, myricanol sensitizes insulin action in myotubes through binding with and activating Nampt.


Assuntos
Insulinas , Nicotinamida Fosforribosiltransferase , Nicotinamida Fosforribosiltransferase/metabolismo , Nicotinamida Fosforribosiltransferase/farmacologia , Fibras Musculares Esqueléticas , Diarileptanoides/farmacologia , Citocinas/metabolismo , Insulinas/metabolismo , Insulinas/farmacologia , NAD/metabolismo
2.
J Digit Imaging ; 36(4): 1597-1607, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36932252

RESUMO

Breast cancer is the leading cause of cancer-related mortality in women worldwide. Despite the rapid developments in diagnostic techniques and medical sciences, pathologic diagnosis is still recognized as the gold standard for disease diagnose. Pathologic diagnosis is a time-consuming task performed for pathologists, needing profound professional knowledge and long-term accumulated diagnostic experience. Therefore, the development of automatic and precise histopathological image classification is essential for medical diagnosis. In this study, an improved VGG network was used to classify the breast cancer histopathological image from intraoperative rapid frozen sections. We adopt a transformed loss function by adding a penalty to cross-entropy in our training stage, which improved the accuracy on test data by 4.39%. Laplacian-4 was used for the enhancement of images, which contributes to the improvement of the accuracy. The accuracy of the proposed model on training data and test data reached 88.70% and 82.27%, respectively, which outperforms the original model by 9.39% of accuracy in test data. The process time was less than 0.25 s per image on average. Meanwhile, the heat maps of predictions were given to show the evidential regions in histopathological images, which could drive improvements in the accuracy, speed, and clinical value of pathological diagnoses. In addition to helping with the actual diagnosis, this technology may be a benefit to pathologists, surgeons, and patients. It might prove to be a helpful tool for pathologists in the future.


Assuntos
Neoplasias da Mama , Medicina , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Secções Congeladas/métodos , Redes Neurais de Computação , Patologistas
3.
Molecules ; 28(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38067519

RESUMO

Alkaloids represent a large family of natural products with diverse structures and bioactivities. These compounds and their derivatives have been widely used in clinics to treat various diseases. The endophytic Aspergillus is a filamentous fungus renowned for its extraordinary ability to produce active natural products of high therapeutic value and economic importance. This review is the first to focus on Aspergillus-derived alkaloids. Through an extensive literature review and data analysis, 263 alkaloids are categorized according to their structural features into those containing cytochalasans, diketopiperazine alkaloids, quinazoline alkaloids, quinoline alkaloids, indole alkaloids, pyrrolidine alkaloids, and others. These metabolites exhibited diverse biological activities, such as antibacterial activity, cytotoxicity, anti-inflammatory activity, and α-glucosidase, ACE, and DPPH inhibitory activities. The bioactivity, structural diversity, and occurrence of these alkaloids are reviewed in detail.


Assuntos
Alcaloides , Produtos Biológicos , Alcaloides/química , Aspergillus/química , Fungos/metabolismo , Alcaloides Indólicos/química , Plantas/metabolismo , Produtos Biológicos/farmacologia
4.
Bioorg Chem ; 113: 105030, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34089946

RESUMO

Five new racemic alkyl-benzofuran dimers, (±)-dieupachinins I-M (1-5), were isolated from the root tubers of Eupatorium chinense, a well-known traditional Chinese medicine for the treatment of diphtheria in Guangdong province. The structures of these compounds, especially the first examples of 12,10'-epoxy dimer dieupachinin I (1), 12-nor-dimer dieupachinin J (2), and 12,12'-dinor-dimer dieupachinin K (3), were elucidated by spectroscopic data analysis. Chiral resolution were further carried out on a cellulose column by HPLC, and compounds 2-5 were successfully separated into two enantiomers, respectively. The absolute configurations of (+)-(2-5) and (-)-(2-5) were established by theoretical ECD calculation. All the compounds were evaluated for insulin-stimulated glucose uptake in C2C12 myotubes and (±)-dieupachinin I (1) exhibited the best activity. Compound 1 enhanced insulin-stimulated glucose uptake via activating the insulin receptor substrate 1/protein kinase B/glycogen synthase kinase-3ß signaling pathway. Moreover, all the isolates were tested for their nitric oxygen (NO) inhibitory effects in lipopolysaccharide-treated RAW264.7 macrophages, and compounds (±)-1, (±)-2, and (±)-4 showed promising inhibitory effects with IC50 values of 6.42 ± 1.85, 6.29 ± 1.94, and 16.03 ± 2.07 µM, respectively. (±)-Dieupachinin I (1) again dose-dependently suppressed LPS-induced expression of inducible NO synthase and nuclear translocation of p65.


Assuntos
Anti-Inflamatórios/química , Benzofuranos/química , Eupatorium/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Benzofuranos/isolamento & purificação , Benzofuranos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Eupatorium/metabolismo , Glucose/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Medicina Tradicional Chinesa , Camundongos , Conformação Molecular , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7
5.
Sensors (Basel) ; 21(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809139

RESUMO

Thermal stress is one of the main sources of micro-electro-mechanical systems (MEMS) devices error. The Wheatstone bridge is the sensing structure of a typical piezoresistive MEMS pressure sensor. In this study, the thermal stress induced by potting adhesive in MEMS pressure sensor was investigated by experiments, calculated by analytics and analyzed by simulations. An experiment system was used to test the sensor at different air pressures and temperatures. The error becomes greater with the decrease in pressure. A set of novel formulas were proposed to calculate the stress-strain on Wheatstone bridge. The error increases with the temperature deviating from 25 °C. A full-scale geometric model was developed, and finite element simulations were performed, to analyze the effect of the stress on MEMS pressure sensor induced by different temperatures and thicknesses of potting adhesive. Simulation results agree well with the experiments, which indicated that there is a 3.48% to 6.50% output error in 0.35 mm potting adhesive at 150 °C. With the thickness of potting adhesive increasing, the variations of output error of the Wheatstone bridge present an N-shaped curve. The output error meets a maximum of 5.30% in the potting adhesive of 0.95 mm and can be reduced to 2.47%, by increasing the potting adhesive to 2.40 mm.

6.
Sensors (Basel) ; 19(14)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336934

RESUMO

Acoustic injection is one of the most dangerous ways of causing micro-electro-mechanical systems (MEMS) failures. In this paper, the failure mechanism of acoustic injection on the microprocessor unit 6050 (MPU6050) accelerometer is investigated by both experiment and simulation. A testing system was built to analyze the performance of the MPU6050 accelerometer under acoustic injection. A MEMS disassembly method was adopted and a MATLAB program was developed to establish the geometric model of MPU6050. Subsequently, a finite element model of MPU6050 was established. Then, the acoustic impacts on the sensor layer of MPU6050 were studied by acoustic-solid coupling simulations. The effects of sound frequencies, pressures and directions were analyzed. Simulation results are well agreed with the experiments which indicate that MPU6050 is most likely to fail under the sounds of 11,566 Hz. The failure mechanism of MPU6050 under acoustic injection is the relative shift of the capacitor flats caused by acoustic-solid resonance that make the sensor detect false signal and output error data. The stress is focused on the center linkage. MPU6050 can be reliable when the sound pressure is lower than 100 dB.

7.
Molecules ; 24(16)2019 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-31426594

RESUMO

Background: Increasing attention has been given to the search for neuroprotective ingredients from natural plants. Myrica rubra bark (MRB) has been used in traditional oriental medicine for over thousand years and has potential neuroprotection. Methods and Results: Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was used to identify the compounds in MRB extract, and the MTT assay was performed to evaluate the neuroprotection of six major compounds from MRB against glutamate-induced damage in PC12 cells. The result displayed nineteen compounds were identified, and myricitrin and myricanol 11-sulfate were shown to have neuroprotection, which prevented cell apoptosis through alleviating oxidative stress by reducing the levels of reactive oxygen species and methane dicarboxylic aldehyde, as well as by enhancing the activities of superoxide dismutase. Conclusions: Several active compounds from MRB may offer neuroprotection and have the potential for the development of new drugs against central nervous system diseases.


Assuntos
Diarileptanoides/química , Flavonoides/química , Myrica/química , Fármacos Neuroprotetores/química , Casca de Planta/química , Ésteres do Ácido Sulfúrico/química , Animais , Apoptose/efeitos dos fármacos , Diarileptanoides/isolamento & purificação , Diarileptanoides/farmacologia , Ativação Enzimática/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Medicina Tradicional Chinesa , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Extratos Vegetais/química , Plantas Medicinais , Ratos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Ésteres do Ácido Sulfúrico/isolamento & purificação , Ésteres do Ácido Sulfúrico/farmacologia , Superóxido Dismutase/metabolismo
8.
Molecules ; 24(1)2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30621331

RESUMO

Four previously undescribed compounds, including three rarely occurring seco-dammarane triterpenoid glycosides and a pentacyclic triterpenic acid, were isolated from a 70% ethanol extract of the leaves of Cyclocarya paliurus (Juglandaceae), along with eleven known triterpenoids. Their structures were determined by spectroscopic techniques, including 2D NMR and HRESIMS, as well as chemical methods. Among them, several triterpenoids enhanced insulin stimulated glucose uptake in both 3T3-L1 adipocytes and C2C12 myotubes. Furthermore, compound 1 dose-dependently increased glucose uptake through activating AMP-activated protein kinase (AMPK)-p38 pathway. Collectively, triterpenoids from C. paliurus could be developed as insulin sensitizers, which might have therapeutic potential for insulin resistance and hyperglycemia.


Assuntos
Adipócitos/efeitos dos fármacos , Glucose/metabolismo , Juglandaceae/química , Terpenos/farmacologia , Células 3T3-L1 , Quinases Proteína-Quinases Ativadas por AMP , Adipócitos/citologia , Animais , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Glicosídeos/química , Insulina , Camundongos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Proteínas Quinases/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade , Terpenos/isolamento & purificação
9.
Planta Med ; 84(18): 1318-1333, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30312974

RESUMO

Liver fibrosis is a wound-healing response characterized by the accumulation of extracellular matrix following various liver injuries, which results in the deformation of the normal liver architecture and the development of liver cirrhosis and even hepatocellular carcinoma. Numerous in vitro and in vivo studies indicated that oxidative stress mediates the initiation and progression of liver fibrosis. Overaccumulation of reactive oxygen species disrupts macromolecules, induces necrosis and apoptosis of hepatocytes, stimulates the production of pro-fibrogenic mediators, and directly activates hepatic stellate cells, thereby resulting in liver damage and initiating liver fibrosis. Ameliorating oxidative stress is a potential therapeutic strategy for the treatment of liver fibrosis. Natural antioxidants have attracted increasing attention in treating liver fibrosis due to their safety and efficacy. In this review, the pathogenesis of liver fibrosis and the role of oxidative stress in liver fibrosis were discussed. Naturally occurring antioxidants that can treat and prevent liver fibrosis were summarized. Advances in clinical trials were also presented. The main purpose of this review is to provide a comprehensive and up-to-date knowledge from the biological importance of oxidative stress in liver fibrosis to representative antioxidants for treating liver fibrosis. Naturally occurring antioxidants show a potential for further investigations as lead compounds in fighting liver fibrosis.


Assuntos
Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Cirrose Hepática/tratamento farmacológico , Alcaloides/farmacologia , Animais , Produtos Biológicos/química , Ensaios Clínicos como Assunto , Flavonoides/farmacologia , Humanos , Cirrose Hepática/etiologia , Estresse Oxidativo/efeitos dos fármacos , Terpenos/farmacologia
10.
J Occup Environ Hyg ; 15(3): 226-234, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29194018

RESUMO

Filtering Facepiece Respirator (FFR) is the most common respirator users in the health care environment utilize for personal protection from outside particles. Comfort and fit are important while wearing an FFR. This paper proposes a novel technology to produce customized face seal design for improving the wearing comfort and fit of FFR wearers. In order to customize the design of face seals, we scanned the faces of three subjects using three-dimensional (3D) laser scanning method. A customized face seal for a 3M 8210 N95 FFR for each headform was designed using reverse engineering technique. Next, the face seal prototypes were fabricated with Acrylonitrile Butadiene Styrene (ABS) plastic using the 3D printing method. A force sensing system based on Arduino Uno R3 was developed, and the force sensor of this system was inserted between the FFR and headform to measure contact pressure. Experimental results showed that the newly designed FFR face seal provided the subjects with an improved contact pressure.


Assuntos
Desenho de Equipamento/métodos , Face/anatomia & histologia , Impressão Tridimensional , Dispositivos de Proteção Respiratória , Expressão Facial , Humanos
11.
J Occup Environ Hyg ; 14(11): D173-D178, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28825873

RESUMO

This article presents an intelligent Filtering Facepiece Respirator (FFR) with a self-adjustable ventilation fan for improved comfort. The ventilation fan with an intelligent control aims to reduce temperature, relative humidity, and CO2 concentrations inside the facepiece. Compared with a previous version of the FFR, the advantage of this new FFR is the intelligent control of the fan's rotation speed based on the change in temperature and relative humidity in the FFR dead space. The design of the control system utilizes an 8-bit, ultra-low power STC15W404AS microcontroller (HongJin technology, Shenzhen, China), and adopts a high-precision AM2320 device (AoSong electronic, Guangzhou, China) as temperature and relative humidity sensor so that control of temperature and relative humidity is realized in real time within the FFR dead space. The ventilation fan is intelligently driven and runs on a rechargeable lithium battery with a power-save mode that provides a correspondingly longer operational time. Meanwhile, the design is simplistic. Two experiments were performed to determine the best location to place the fan.


Assuntos
Desenho de Equipamento , Dispositivos de Proteção Respiratória , Ventilação/instrumentação , Dióxido de Carbono , Humanos , Umidade , Temperatura
12.
J Occup Environ Hyg ; 13(5): 372-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26653154

RESUMO

This article presents a reverse modeling of the headform when wearing a filtering facepiece respirator (FFR) and a computational fluid dynamics (CFD) simulation based on the modeling. The whole model containing the upper respiratory airway, headform, and FFR was directly recorded by computed tomography (CT) scanning, and a medical contrast medium was used to make the FFR "visible." The FFR was normally worn by the subject during CT scanning so that the actual deformation of both the FFR and the face muscles during contact can be objectively conserved. The reverse modeling approach was introduced to rebuild the geometric model and convert it into a CFD solvable model. In this model, we conducted a transient numerical simulation of air flow containing carbon dioxide, thermal dynamics, and pressure and wall shear stress distribution in the respiratory system taking into consideration an individual wearing a FFR. The breathing cycle was described as a time-dependent profile of the air velocity through the respiratory airway. The result shows that wearing the N95 FFR results in CO2 accumulation, an increase in temperature and pressure elevation inside the FFR cavity. The volume fraction of CO2 reaches 1.2% after 7 breathing cycles and then is maintained at 3.04% on average. The wearers re-inhale excessive CO2 in every breathing cycle from the FFR cavity. The air temperature in the FFR cavity increases rapidly at first and then stays close to the exhaled temperature. Compared to not wearing an FFR, wearers have to increase approximately 90 Pa more pressure to keep the same breathing flow rate of 30.54 L/min after wearing an FFR. The nasal vestibule bears more wall shear stress than any other area in the airway.


Assuntos
Dióxido de Carbono/análise , Fenômenos Fisiológicos Respiratórios , Dispositivos de Proteção Respiratória , Simulação por Computador , Desenho de Equipamento , Humanos , Hidrodinâmica , Modelos Teóricos , Pressão , Temperatura
13.
J Occup Environ Hyg ; 13(3): D50-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26558322

RESUMO

This article presents a computational study on contact characteristics of contact pressure and resultant deformation between an N95 filtering facepiece respirator and a newly developed digital headform. The geometry of the headform model is obtained based on computed tomography scanning of a volunteer. The segmentation and reconstruction of the headform model is performed by Mimics v16.0 (Materialise, Leuven, Belgium), which is a medical image processing software. The respirator model is obtained by scanning the surface of a 3M 8210 N95 respirator using a 3D digitizer and then the model is transformed by Geomagic Studio v12.0 (3D system, Rock Hill, SC), a reverse engineering software. The headform model contains a soft tissue layer, a skull layer, and a separate nose. The respirator model contains two layers (an inner face sealing layer and an outer layer) and a nose clip. Both the headform and respirator are modeled as solid elements and are deformable. The commercial software, LS-DYNA (LSTC, Livermore, CA), is used to simulate the contact between the respirator and headform. Contact pressures and resultant deformation of the headform are investigated. Effects of respirator stiffness on contact characteristics are also studied. A Matlab (MathWorks, Natick, MA) program is developed to calculate local gaps between the headform and respirator in the stable wearing state.


Assuntos
Simulação por Computador , Desenho de Equipamento , Dispositivos de Proteção Respiratória , Análise de Elementos Finitos , Cabeça , Humanos , Teste de Materiais/métodos , Modelos Anatômicos , Exposição Ocupacional/prevenção & controle , Pressão , Estresse Mecânico , Tomografia Computadorizada por Raios X
14.
Yao Xue Xue Bao ; 50(6): 746-8, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26521447

RESUMO

To study the chemical constituents from the bark of Myrica rubra, fourteen compounds were isolated from the methanolic extract using various chromatographic techniques, including silica gel, Sephadex LH-20 and preparative HPLC. Their structures were identified on the basis of chemical properties and spectroscopic data, as 3, 5-dimethoxy-4-hydroxymyricanol (1), myricanol (2), myricanone (3), myricanol 11-sulfate (4), myricitrin (5), quercetin (6), quercetin-3-rhamnoside (7), tamarixol (8), uvaol (9), ursolic acid (10), taraxerol (11), myricadiol (12), ß-sitosterol (13) and ß-daucosterol (14). Among them, compound 1 is a new compound, named as 3, 5-dimethoxy-4-hydroxymyricanol, compounds 8, 9 were isolated from the genus Myrica for the first time.


Assuntos
Diarileptanoides/química , Myrica/química , Compostos Fitoquímicos/química , Casca de Planta/química , Diarileptanoides/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação
15.
MedComm (2020) ; 5(6): e566, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38868327

RESUMO

Aging is a process that represents the accumulation of changes in organism overtime. In biological level, accumulations of molecular and cellular damage in aging lead to an increasing risk of diseases like sarcopenia. Sarcopenia reduces mobility, leads to fall-related injuries, and diminishes life quality. Thus, it is meaningful to find out novel therapeutic strategies for sarcopenia intervention that may help the elderly maintain their functional ability. Oxidative damage-induced dysfunctional mitochondria are considered as a culprit of muscle wasting during aging. Herein, we aimed to demonstrate whether myricanol (MY) protects aged mice against muscle wasting through alleviating oxidative damage in mitochondria and identify the direct protein target and its underlying mechanism. We discovered that MY protects aged mice against the loss of muscle mass and strength through scavenging reactive oxygen species accumulation to rebuild the redox homeostasis. Taking advantage of biophysical assays, peroxiredoxin 5 was discovered and validated as the direct target of MY. Through activating peroxiredoxin 5, MY reduced reactive oxygen species accumulation and damaged mitochondrial DNA in C2C12 myotubes. Our findings provide an insight for therapy against sarcopenia through alleviating oxidative damage-induced dysfunctional mitochondria by targeting peroxiredoxin 5, which may contribute an insight for healthy aging.

16.
Int J Nanomedicine ; 19: 6777-6809, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983131

RESUMO

Chloroquine is a common antimalarial drug and is listed in the World Health Organization Standard List of Essential Medicines because of its safety, low cost and ease of use. Besides its antimalarial property, chloroquine also was used in anti-inflammatory and antivirus, especially in antitumor therapy. A mount of data showed that chloroquine mainly relied on autophagy inhibition to exert its antitumor effects. However, recently, more and more researches have revealed that chloroquine acts through other mechanisms that are autophagy-independent. Nevertheless, the current reviews lacked a comprehensive summary of the antitumor mechanism and combined pharmacotherapy of chloroquine. So here we focused on the antitumor properties of chloroquine, summarized the pharmacological mechanisms of antitumor progression of chloroquine dependent or independent of autophagy inhibition. Moreover, we also discussed the side effects and possible application developments of chloroquine. This review provided a more systematic and cutting-edge knowledge involved in the anti-tumor mechanisms and combined pharmacotherapy of chloroquine in hope of carrying out more in-depth exploration of chloroquine and obtaining more clinical applications.


Assuntos
Antineoplásicos , Autofagia , Cloroquina , Neoplasias , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Autofagia/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico
17.
Mater Horiz ; 11(6): 1414-1425, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38363093

RESUMO

Taking advantage of a hybrid generator to simultaneously collect polynary energy from a single energy source provides a feasible solution for the energy dilemma in the new era. Herein, we integrate a triboelectric nanogenerator and a thermoelectric generator for polynary energy harvesting and self-powered sensing of heatwaves in large-scale industrial factory buildings, which contains both thermal energy and wind energy. The new design of the fan-shaped rotation triboelectric nanogenerator (FR-TENG) makes it more compact and easily integrated. After structure modeling, the energy conversion efficiency of the FR-TENG can reach a maximum of 37.2%, which can successfully power a Bluetooth hygrothermograph transmitting environmental information wirelessly every 30 s at a wind speed of 4.67 m s-1. An all-inorganic flexible thermoelectric generator (iThEG) is developed based on copper and constantan with an output power density of 0.73 W m-3, and maintains its original mechanical properties after 10 000 bending tests. Moreover, a self-powered hot wind sensing system based on Labview is established which can display wind-speed and wind-temperature in real time. The working concept presented here is also applicable to other single energy sources containing multiple energy forms, such as falling raindrops and sunlight, which can lift energy utilization and conversion efficiency and alleviate the energy crisis.

18.
Regen Biomater ; 11: rbae065, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933085

RESUMO

Cancer is one of the most challenging diseases in the world. Recently, iron oxide nanoparticles (IONPs) are emerging materials with rapid development and high application value, and have shown great potential on tumor therapy due to their unique magnetic and biocompatible properties. However, some data hint us that IONPs were toxic to normal cells and vital organs. Thus, more data on biosafety evaluation is urgently needed. In this study, we compared the effects of silicon-coated IONPs (Si-IONPs) on two cell types: the tumor cells (Hela) and the normal cells (HEK293T, as 293 T for short), compared differences of protein composition, allocation and physical characteristics between these two cells. The major findings of our study pointed out that 293 T cells death occurred more significant than that of Hela cells after Si-IONPs treatment, and the rate and content of endocytosis of Si-IONPs in 293 T cells was more prominent than in Hela cells. Our results also showed Si-IONPs significant promoted the production of reactive oxygen species and disturbed pathways related to oxidative stress, iron homeostasis, apoptosis and ferroptosis in both two types of cells, however, Hela cells recovered from these disturbances more easily than 293 T. In conclusion, compared with Hela cells, IONPs are more likely to induce 293 T cells death and Hela cells have their own unique mechanisms to defense invaders, reminding scientists that future in vivo and in vitro studies of nanoparticles need to be cautious, and more safety data are needed for further clinical treatment.

19.
Int J Biol Sci ; 20(14): 5510-5530, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39494324

RESUMO

Celastrol, a compound derived from traditional Chinese medicine, has therapeutic effects and has been used to treat inflammation-related diseases, cancer, cardiovascular diseases, and neurodegenerative diseases. However, current reviews lack a comprehensive and systematic summary of the anti-tumor mechanisms and molecular targets of celastrol. For this reason, this paper reviews the anticancer properties of celastrol and the molecular mechanisms underlying its anticancer effects. This paper primarily focuses on the mechanism of action of celastrol in terms of inhibition of cell proliferation and regulation of the cell cycle, regulation of apoptosis and autophagy, inhibition of cell invasion and metastasis, anti-inflammation, regulation of immunotherapy, and angiogenesis. More importantly, the target proteins of celastrol identified by chemical proteomics or other methods are highlighted, providing detailed targets with novel therapeutic potential for anti-tumor treatment. In addition, we describe the side effects and strategies to improve the bioavailability of celastrol. In summary, this paper analyzes celastrol, a natural compound with therapeutic effects and clear targets, aiming to draw more attention from the scientific and pharmacological communities and accelerating its clinical application for the benefit of cancer patients.


Assuntos
Neoplasias , Triterpenos Pentacíclicos , Triterpenos , Humanos , Triterpenos/uso terapêutico , Triterpenos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Apoptose/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos
20.
Int J Nanomedicine ; 19: 1385-1408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371457

RESUMO

Background: Acute kidney injury (AKI) is a syndrome, posing a substantial healthcare burden. The pathological basis of AKI is associated with inflammation and oxidative stress which cause additional damage to mitochondria. Artesunate (ATS) is a derivative of artemisinin isolated from Artemisia annua L. that is an effective treatment for malaria and favored for the prevention and treatment of kidney diseases. However, there are still challenges related to its efficacy, including poor water solubility, limited oral bioavailability and short half-life. Liposome-based nanoparticles are used for drug delivery due to their ideal biocompatibility and their ability to improve the bioavailability of specific drugs and enhance drug efficacy. Methods: In this study, a novel TPP-based natural ATS-nanoliposome, namely T-A-Ls, was applied for the treatment of AKI. ATS was encapsulated with or without triphenylphosphonium (TPP)-modified nanoliposomes. AKI was induced by cisplatin in C57BL/6J mice and a cisplatin-induced injury model was generated in HK-2 cells in vitro. Blood urea nitrogen (BUN), serum creatinine (Scr) measurements and section staining were utilized to assess renal protective effect of T-A-Ls. Inflammatory-related factors and proteins were quantified via Elisa, Immunofluorescence and Western Blot (WB). The anti-mitochondrial oxidative stress effect of T-A-Ls was determined by ROS, JC-1 and oxygen consumption rate (OCR) kits. Immunohistochemistry and WB were conducted to measure associated protein expressions. In vivo biodistribution and the concentration of T-A-Ls in kidney were also explored. Results: T-A-Ls exhibited good oxidative resistance, preferential renal uptake, mitochondrial targeting, and it ameliorated kidney injury in cisplatin-induced AKI mice. Mitochondrial dysfunction, ATP production and respiratory capacity were improved in damaged HK-2 cells; ROS content decreased while mitochondrial membrane potential recovered. T-A-Ls exerted renal protection by inhibiting inflammation and reducing oxidative stress; these effects were mediated by a downregulation in the expression of RAGE and iNOS and an upregulation in both Nrf2 and HO-1. Conclusion: T-A-Ls could improve the delivery of ATS to the kidney, offering a promising avenue to treat AKI.


Assuntos
Injúria Renal Aguda , Cisplatino , Compostos Organofosforados , Animais , Camundongos , Cisplatino/toxicidade , Artesunato , Espécies Reativas de Oxigênio/metabolismo , Distribuição Tecidual , Camundongos Endogâmicos C57BL , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/prevenção & controle , Rim , Estresse Oxidativo , Mitocôndrias/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Sistemas de Liberação de Medicamentos/efeitos adversos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA