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1.
Front Public Health ; 12: 1358184, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605878

RESUMO

The rapid development of the Hospital Information System has significantly enhanced the convenience of medical research and the management of medical information. However, the internal misuse and privacy leakage of medical big data are critical issues that need to be addressed in the process of medical research and information management. Access control serves as a method to prevent data misuse and privacy leakage. Nevertheless, traditional access control methods, limited by their single usage scenario and susceptibility to single point failures, fail to adapt to the polymorphic, real-time, and sensitive characteristics of medical big data scenarios. This paper proposes a smart contracts and risk-based access control model (SCR-BAC). This model integrates smart contracts with traditional risk-based access control and deploys risk-based access control policies in the form of smart contracts into the blockchain, thereby ensuring the protection of medical data. The model categorizes risk into historical and current risk, quantifies the historical risk based on the time decay factor and the doctor's historical behavior, and updates the doctor's composite risk value in real time. The access control policy, based on the comprehensive risk, is deployed into the blockchain in the form of a smart contract. The distributed nature of the blockchain is utilized to automatically enforce access control, thereby resolving the issue of single point failures. Simulation experiments demonstrate that the access control model proposed in this paper effectively curbs the access behavior of malicious doctors to a certain extent and imposes a limiting effect on the internal abuse and privacy leakage of medical big data.


Assuntos
Pesquisa Biomédica , Blockchain , Big Data , Simulação por Computador , Comportamentos Relacionados com a Saúde
2.
J Comput Biol ; 31(2): 99-116, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271572

RESUMO

Identifying cancer subtype-specific driver genes from a large number of irrelevant passengers is crucial for targeted therapy in cancer treatment. Recently, the rapid accumulation of large-scale cancer genomics data from multiple institutions has presented remarkable opportunities for identification of cancer subtype-specific driver genes. However, the insufficient subtype samples, privacy issues, and heterogenous of aberration events pose great challenges in precisely identifying cancer subtype-specific driver genes. To address this, we introduce privatedriver, the first model for identifying subtype-specific driver genes that integrates genomics data from multiple institutions in a data privacy-preserving collaboration manner. The process of identifying subtype-specific cancer driver genes using privatedriver involves the following two steps: genomics data integration and collaborative training. In the integration process, the aberration events from multiple genomics data sources are combined for each institution using the forward and backward propagation method of NetICS. In the collaborative training process, each institution utilizes the federated learning framework to upload encrypted model parameters instead of raw data of all institutions to train a global model by using the non-negative matrix factorization algorithm. We applied privatedriver on head and neck squamous cell and colon cancer from The Cancer Genome Atlas website and evaluated it with two benchmarks using macro-Fscore. The comparison analysis demonstrates that privatedriver achieves comparable results to centralized learning models and outperforms most other nonprivacy preserving models, all while ensuring the confidentiality of patient information. We also demonstrate that, for varying predicted driver gene distributions in subtype, our model fully considers the heterogeneity of subtype and identifies subtype-specific driver genes corresponding to the given prognosis and therapeutic effect. The success of privatedriver reveals the feasibility and effectiveness of identifying cancer subtype-specific driver genes in a data protection manner, providing new insights for future privacy-preserving driver gene identification studies.


Assuntos
Neoplasias do Colo , Privacidade , Humanos , Oncogenes , Algoritmos , Benchmarking
3.
Int J Numer Method Biomed Eng ; 39(6): e3705, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37005088

RESUMO

Extracorporeal membrane oxygenation (ECMO) is a life support system used in the treatment of severe respiratory and circulatory failure. High shear stress caused by the high rotational speed of centrifugal blood pumps can cause hemolysis and platelet activation, which are among the major factors leading to the complications of the ECMO system. In this study, a novel blood pump named rotary displacement blood pump (RDBP), which can considerably reduce rotational speed and shear stress while ensuring the normal pressure flow relationship, was proposed. We employed computational fluid dynamics (CFD) analysis to investigate the performance of RDBP under adult ECMO support operating conditions (5 L/min with 350 mmHg). The efficiency and H-Q curves of the RDBP were calculated to evaluate its hydraulic performance, and pressure, flow patterns, and shear stress distribution were analyzed to estimate the hemodynamic characteristics in the pump. In addition, the modified index of hemolysis (MIH) was calculated for the RDBP based on a Eulerian approach. The hydraulic efficiency of the RDBP was 47.28%. The velocity distribution of flow field in the pump was relatively uniform. Most of the liquid (more than 75%) in the pump was exposed to low scale shear stress (<1 Pa), which was close to normal physiological conditions. The gap area was the main distribution location of high scale shear stress. The high wall shear stress (>9 Pa) volume fraction of the RDBP was small and located in the boundary areas between the rotor's edge and the housing. The MIH value of the RDBP was 9.87 ± 0.93 (mean ± SD). The RDBP can achieve better hydraulic efficiency and hemodynamic performance at lower rotational speed. The design of this novel pump is expected to provide a new direction for developing a blood pump for ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Coração Auxiliar , Humanos , Desenho de Equipamento , Hemólise , Hemodinâmica/fisiologia
4.
Adv Sci (Weinh) ; 9(12): e2103875, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35182046

RESUMO

The treatment of peripheral nerve defects has always been one of the most challenging clinical practices in neurosurgery. Currently, nerve autograft is the preferred treatment modality for peripheral nerve defects, while the therapy is constantly plagued by the limited donor, loss of donor function, formation of neuroma, nerve distortion or dislocation, and nerve diameter mismatch. To address these clinical issues, the emerged nerve guide conduits (NGCs) are expected to offer effective platforms to repair peripheral nerve defects, especially those with large or complex topological structures. Up to now, numerous technologies are developed for preparing diverse NGCs, such as solvent casting, gas foaming, phase separation, freeze-drying, melt molding, electrospinning, and three-dimensional (3D) printing. 3D printing shows great potential and advantages because it can quickly and accurately manufacture the required NGCs from various natural and synthetic materials. This review introduces the application of personalized 3D printed NGCs for the precision repair of peripheral nerve defects and predicts their future directions.


Assuntos
Regeneração Nervosa , Nervos Periféricos , Nervos Periféricos/fisiologia , Impressão Tridimensional , Alicerces Teciduais/química
5.
Front Bioeng Biotechnol ; 10: 1069932, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36636700

RESUMO

Infection is one of the most serious complications harmful to human health, which brings a huge burden to human health. Bone infection is one of the most common and serious complications of fracture and orthopaedic surgery. Antibacterial treatment is the premise of bone defect healing. Among all the antibacterial strategies, irritant antibacterial materials have unique advantages and the ability of targeted therapy. In this review, we focus on the research progress of irritating materials, the development of antibacterial materials and their advantages and disadvantages potential applications in bone infection.

6.
Int J Biol Macromol ; 183: 2121-2130, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34087301

RESUMO

Compounding is a safe method to avoid limitations of a singular gel. Here, composite gels were prepared with konjac glucomannan (KGM) and gum arabic (GA) and evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), water solubility index (WSI), water absorption index (WAI), texture profile analysis (TPA) and rheological analysis. The gel stratified when GA concentration ≥ 2.5%. FTIR indicated that the interactions of KGM and GA were mainly related to hydrogen bonds and acetyl groups, and the solution separated from gels only included GA and water molecules. The microstructures became denser and contained smaller holes at high GA concentrations as seen by SEM. WSI and WAI both increased with GA increasing. Hardness and springiness dropped when GA concentration increased from 0 to 2.0%, but they increased when GA increased from 2.0% to 4.0%. Rheological analysis showed the gels were non-Newtonian pseudoplastic fluids, with anti-thixotropy (GA ≤ 3.5%) and thixotropy (GA ≥ 4.0%). Furthermore, the gels could be classified as non-covalent gels, with higher gel strength at high GA concentrations. The non-covalent linkages included hydrogen bonding and hydrophobic interaction, and hydrogen bonding held the dominated status. Therefore, KGM and GA have antagonistic and synergistic effects.


Assuntos
Goma Arábica/química , Mananas/química , Coloides , Géis , Dureza , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Porosidade , Viscosidade , Água/química
7.
Chin J Integr Med ; 27(5): 336-344, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33420900

RESUMO

OBJECTIVE: To investigate whether ginsenoside Rb1 (Rb1) can protect human umbilical vein endothelial cells (HUVECs) against high glucose-induced apoptosis and examine the underlying mechanism. METHODS: HUVECs were divided into 5 groups: control group (5.5 mmol/L glucose), high glucose (HG, 40 mmol/L) treatment group, Rb1 (50 µ mol/L) treatment group, Rb1 plus HG treatment group, and Rb1 and 3-(1H-1,2,3-triazol-4-yl) pyridine (3-TYP, 16 µ mol/L) plus HG treatment group. Cell viability was evaluated by cell counting kit-8 assay. Mitochondrial and intracellular reactive oxygen species were detected by MitoSox Red mitochondrial superoxide indicator and dichloro-dihydro-fluorescein diacetate assay, respectively. Annexin V/propidium iodide staining and fluorescent dye staining were used to measure the apoptosis and the mitochondrial membrane potential of HUVECs, respectively. The protein expressions of apoptosis-related proteins [Bcl-2, Bax, cleaved caspase-3 and cytochrome c (Cyt-c)], mitochondrial biogenesis-related proteins [proliferator-activated receptor gamma coactivator 1-alpha, nuclear respiratory factor-1 and mitochondrial transcription factor A)], acetylation levels of forkhead box O3a and SOD2, and sirtuin-3 (SIRT3) signalling pathway were measured by immunoblotting and immunoprecipitation. RESULTS: Rb1 ameliorated survival in cells in which apoptosis was induced by high glucose (P<0.05 or P<0.01). Upon the addition of Rb1, mitochondrial and intracellular reactive oxygen species generation and malondialdehyde levels were decreased (P<0.01), while the activities of antioxidant enzymes were increased (P<0.05 or P<0.01). Rb1 preserved the mitochondrial membrane potential and reduced the release of Cyt-c from the mitochondria into the cytosol (P<0.01). In addition, Rb1 upregulated mitochondrial biogenesis-associated proteins (P<0.01). Notably, the cytoprotective effects of Rb1 were correlated with SIRT3 signalling pathway activation (P<0.01). The effect of Rb1 against high glucose-induced mitochondria-related apoptosis was restrained by 3-TYP (P<0.05 or P<0.01). CONCLUSION: Rb1 could protect HUVECs from high glucose-induced apoptosis by promoting mitochondrial function and suppressing oxidative stress through the SIRT3 signalling pathway.


Assuntos
Mitocôndrias , Apoptose , Células Endoteliais , Ginsenosídeos , Glucose/metabolismo , Glucose/toxicidade , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Sirtuína 3 , Ubiquitina-Proteína Ligases/metabolismo , Cordão Umbilical
8.
ACS Appl Mater Interfaces ; 13(4): 5266-5274, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33491442

RESUMO

Harvesting electromagnetic (EM) energy from the environment and converting it into useful micropower is a new and ideal way to eliminate EM radiation and while providing power for microelectronic devices. The key material of this technology is broadband, ultralight, and ultrathin EM-wave-absorbing materials, whose preparation remains challenging. Herein, a high magnetic field (HMF) strategy is proposed to prepare a biomass-derived CoFe/carbon fiber (CoFe/CF) composite, in which CoFe magnetic particles are aligned in CFs, creating magnetic coupling and fast electron transmission channels. The graphitization degree of CFs is improved via the "migration catalysis" of CoFe particles under HMF. The HMF-derived CoFe/CF shows a largely broadened EM wave absorption bandwidth under ultralight and ultrathin conditions (1.5 mm). Its absorption bandwidth increases 5-10 times compared with conventional CoFe/CF that has randomly distributed CoFe particles and surpasses the reported analogues. A device model for EM energy absorption and reuse is designed based on the HMF-derived CoFe/CF membrane, which exhibits a 300% higher capability than conventional CoFe/CF membrane in converting EM energy to thermal energy. This work offers a new strategy for the design and fabrication of broadband, ultrathin, and ultralight EM wave absorption materials and demonstrates a potential conversion approach of the waste EM energy.

10.
Int J Biol Macromol ; 167: 834-844, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33181211

RESUMO

A polylactide composite fracture fixator loaded with vancomycin cationic liposome (PLA@VL) was prepared by reverse evaporation method. The method of cationic liposome encapsulating vancomycin could effectively improve antibacterial property and achieve drug sustained release effect, so as to reduce toxicity of antibiotics in vivo. Scanning electron microscope (SEM) was used to observe morphology and Fourier transform infrared spectroscopy (FTIR) was used to detect the composition of the internal fixator. In vitro drug release model, in vitro degradation model and body fluid osteogenesis model were designed in this study. On the other hand, the experiments of inhibition zone and MC3T3-E1 osteoblasts in mice were conducted to explore antibacterial property, cell activity and adhesion of the PLA@VL composite internal fixator. Alkaline phosphatase (ALP) staining method and alizarin red assay were used to detect the osteogenic induction ability of the composite internal fixator. Finally, mice fracture models were established to verify osteogenic and anti-infection abilities of the composite internal fixator in vivo. The results showed that MC3T3-E1 cells had better adhesion and proliferation abilities on the PLA@VL composite internal fixator than on the PLA fixator, which indicated that the PLA@VL composite internal fixator possessed excellent osteogenic and anti-infection abilities both in vivo and in vitro. Therefore, the above experiments showed that the fracture internal fixator combined with vancomycin cationic liposome had better biocompatibility, antibacterial ability and osteogenic ability, which provides a promising anti-infection material for the clinical field of fracture.


Assuntos
Antibacterianos/administração & dosagem , Fixadores Internos , Lipossomos/química , Poliésteres/análise , Vancomicina/administração & dosagem , Fosfatase Alcalina/metabolismo , Animais , Antibacterianos/química , Materiais Biocompatíveis/química , Biomarcadores , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Liberação Controlada de Fármacos , Lipossomos/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Osteogênese/efeitos dos fármacos , Solubilidade , Análise Espectral , Engenharia Tecidual , Alicerces Teciduais/química , Vancomicina/química
11.
Front Pharmacol ; 11: 1286, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973517

RESUMO

Advanced drug carriers for the controlled release of chemotherapeutics in the treatment of malignant tumors have drawn significant notice in recent years. In the current study, microspheres (MPs) loaded with docetaxel (DTX) were prepared using polylactic-co-glycolic acid copolymer (PLGA). The double emulsion solvent evaporation method is simple to perform, and results in high encapsulation efficiency. Electron micrographs of the MPs showed that controlling the shear rate can effectively control the size of the MPs. At present, most DTX sustained-release carriers cannot maintain stable and long-term local drug release. The 1.68 µm DTX-loaded microspheres (MP/DTX) with elastase was completely degraded in 14 d. This controlled degradation period is similar to a course of treatment for most cancers. The drug release profile of all kinds of MP/DTX demonstrated an initial rapid release, then slower and stable release to the end. The current study demonstrates that it is possible to create drug-loaded MPs with specific degradation times and drug release curves, which may be useful in achieving optimal treatment times and drug release rates for different diseases, and different drug delivery routes. The initial burst release reaches the effective concentration of the drug at the beginning of release, and then the drug concentration is maintained by stable release to reduce the number of injections and improve patient compliance.

12.
Inflammation ; 43(6): 2372-2378, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32737656

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has become a major health concern worldwide. The aim of this study was to investigate the effect and mechanism of electroacupuncture (EA) on nonalcoholic fatty liver disease (NAFLD) in rats induced by high-fat diet (HFD). A model of nonalcoholic fatty liver in rats induced by high fat was established. Rats in the control group were fed standard diet. The rats in model group and EA group were fed with HFD. From the fifth week, the rats in EA group were treated with EA ("FengLongXue," "YinLingQuanXue," "SanYinJiaoXue") for 2 weeks respectively. EA could significantly reduce serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), serum triglyceride (TG), serum cholesterol (TC), and serum cytokines, and improve liver histopathological changes in rats. EA also could regulate the levels of Sirt1/NF-κB pathway in rat liver. EA relieved liver injury in NAFLD rats, and its mechanism may be related to the regulation of Sirt1/NF-κB pathway in rats. This is the first report that electroacupuncture alleviates liver inflammatory reaction of nonalcoholic fatty liver by enhancing Sirt1 expression and inhibiting NLRP3/NF-kB signal pathway.


Assuntos
Eletroacupuntura/métodos , Inflamação , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sirtuína 1/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Colesterol/sangue , Citocinas/sangue , Citocinas/metabolismo , Dieta Hiperlipídica , Progressão da Doença , Metabolismo dos Lipídeos , Lipídeos/química , Fígado/metabolismo , Masculino , Hepatopatia Gordurosa não Alcoólica/terapia , Ratos , Ratos Sprague-Dawley , Transaminases/sangue , Triglicerídeos/sangue
13.
Sci Total Environ ; 730: 138930, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32388372

RESUMO

We reported the effective removal of chromium(VI) (Cr(VI)) from wastewater with nitrogen and sulfur codoped micro-mesoporous carbon sheets (N,S-MMCSs), which were fabricated by pyrolysis of natural biomass (luffa sponge) followed by chemical activation and hydrothermal treatment. N,S-MMCSs possessed a hierarchical micro-mesoporous sheet-like framework, large specific surface area (1525.45 m2 g-1), high pore volume (1.21 cm3 g-1), and appropriate N (1.81 wt%) and S (1.01 wt%) co-doping. Batch adsorption experiments suggested that Cr(VI) adsorption by the N,S-MMCSs increased with increase the solution acidity, adsorbent dosage, Cr(VI) concentration, temperature, and time. The Cr(VI) adsorption was mainly controlled by the chemisorptions and could be well interpreted by the Langmuir isotherm and pseudo-second-order kinetic models. The maximum adsorption capacities of Cr(VI) were 217.39, 277.78, and 312.50 mg g-1 at 298, 308, and 318 K, respectively. The Cr(VI) adsorption procedure was spontaneous, endothermic, and randomness. The Cr(VI) adsorption mechanism followed the physical adsorption, electrostatic attraction, in situ reduction, and surface chelation. Besides, the density functional theory (DFT) calculation demonstrated that the N and S co-doping could decrease the adsorption energy and enhance the attractive interaction between N,S-MMCSs and Cr(VI) through the synergistic effect, and thus significantly improve the Cr(VI) adsorption property.


Assuntos
Biomassa , Purificação da Água , Adsorção , Carbono , Cromo , Concentração de Íons de Hidrogênio , Cinética , Nitrogênio , Enxofre , Poluentes Químicos da Água
14.
J Biomech ; 103: 109425, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32098680

RESUMO

The role of pulsatile unloading in hemodynamic changes in intraventricular flow and ventricular wall stress remains unknown. In this study, a finite element model of the left ventricle (LV) is proposed to calculate the mechanical response. The constitutive model of the LV is composed of a quasi-incompressible transversely isotropic model and an active contraction of the myocardium model. Pulsatile unloading is provided by the left ventricular assist device (LVAD), which is implanted between the aortic root and aortic arch. Support models (constant speed and co-pulse) were utilized to study the effect of pulsatile unloading on intraventricular flow and ventricular stress. The result indicates that the formation time of the vortex increases under pulsatile unloading. The area rate of high time-averaged wall shear stress (TAWSS) increased after pulsatile unloading. The area of the high oscillatory shear index (OSI) region (OSI > 0.375) was calculated for heart failure, constant speed, and co-pulse (9.9 cm2, 9.6 cm2, and 9.2 cm2, respectively). The maximum value of the stress that reflects the level of stretch declined after pulsatile unloading (66.4 kPa, 30.9 kPa, and 21.3 kPa, respectively). Besides, pulsatile unloading impacts the maximum value of thickness at the ventricular wall (-0.75 mm, -1 mm, and -1.25 mm, respectively). The change ratios of the thickness are 10%, 14%, and 17%, respectively. In conclusion, pulsatile unloading contributes to the distribution of intraventricular flow and the formation time of the vortex. Co-pulse support significantly reduces the maximum value of the ventricular wall stress and the area of high stress on the ventricular wall.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Insuficiência Cardíaca/terapia , Ventrículos do Coração , Hemodinâmica , Humanos , Fluxo Pulsátil
15.
ACS Biomater Sci Eng ; 6(9): 5181-5190, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-33455268

RESUMO

Titanium alloy prostheses have been widely used for the treatment of orthopedic diseases, in which the interconnected porosity and appropriate pore size are crucial for the osseointegration capacity. Three-dimensional (3D) printing technology provides an efficient method to construct prosthesis scaffolds with controllable internal and surface structure, but printing high-porosity (>60%) scaffolds with pore diameters below 300 µm as implants structures has not yet been studied. In this work, four types of titanium alloy scaffolds with interconnected porosity more than 70% were successfully prepared by selective laser melting (SLM). The actual mean pore sizes of cylindrical scaffolds are 542, 366, 202, and 134 µm. Through the in vitro characterization of the scaffolds, in vivo experiments, and mechanical experiments, it is concluded that as the scaffold pore diameter decreases, the titanium alloy scaffold with diameter of 202 µm has the strongest osseointegration ability and is also the most stable one with the surrounding bone. These findings provide a reference for the clinical pore-size design of porous scaffolds with optimal bone growth stability on the surface of the titanium alloy implant.


Assuntos
Osseointegração , Titânio , Ligas , Porosidade , Impressão Tridimensional , Próteses e Implantes
16.
Nanomedicine ; 23: 102085, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442580

RESUMO

Osteosarcoma (OS) is the most common malignant bone tumor with high metastasis and mortality. Neoadjuvant chemotherapy is an effective therapeutic regimen, but the clinical application is limited by the unsatisfactory efficacies and considerable side effects. In this study, the reduction-responsive polypeptide micelles based on methoxy poly(ethylene glycol)-block-poly(S-tert-butylmercapto-L-cysteine) copolymers (mPEG113-b-PBMLC4, P4M, and mPEG113-b-PBMLC9, P9M) were developed to control the delivery of doxorubicin (DOX) in OS therapy. Compared to free DOX, P4M/DOX and P9M/DOX exhibited 2.6 and 3.5 times increase in the area under the curve of pharmacokinetics, 1.6 and 2.0 times increase in tumor accumulation, and 1.6 and 1.7 times decrease of the distribution in the heart. Moreover, the selective accumulation of micelles, especially P9M/DOX, in tumors induced stronger antitumor effects on both primary and lung metastatic OSs with less systematic toxicity. These micelles with smart responsiveness to intracellular microenvironments are highly promising for the targeted delivery of clinical chemotherapeutic drugs in cancer therapy.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Doxorrubicina , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Osteossarcoma/tratamento farmacológico , Peptídeos , Animais , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanomedicina , Metástase Neoplásica , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Oxirredução , Peptídeos/química , Peptídeos/farmacologia , Ratos , Ratos Wistar
17.
J Cardiovasc Pharmacol ; 75(2): 155-167, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31658172

RESUMO

Oxidative low-density lipoprotein (ox-LDL) induces endothelium senescence and promotes atherosclerosis. Ginsenoside Rb1 (gRb1) has been proved to protect human umbilical vein cells (HUVECs), but its effect on ox-LDL-induced endothelium senescence and the underlying mechanism remains unknown. This study is to explore the involvement of the SIRT1/Beclin-1/autophagy axis in the effect of gRb1 on protecting endothelium against ox-LDL-induced senescence. Hyperlipidemia of Sprague Dawley rats was induced by high-fat diet, and gRb1 was intraperitoneal injected. A senescence model of HUVECs induced by ox-LDL was also established. The results showed that gRb1 alleviated hyperlipidemia-induced endothelium senescence and ox-LDL-induced HUVECs senescence. GRb1 also restored the reductions in SIRT1 and autophagy, which were involved in the anti-senescence effects. Beclin-1 acetylation was reduced, and the correlation between SIRT1 and Beclin-1 was increased by gRb1. Results of our study demonstrated the anti-senescence function of gRb1 against hyperlipidemia in the endothelium, and the underlying mechanism involves the SIRT1/Beclin-1/autophagy axis.


Assuntos
Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Senescência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Ginsenosídeos/farmacologia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Lipoproteínas LDL/toxicidade , Sirtuína 1/metabolismo , Acetilação , Animais , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Células Endoteliais/enzimologia , Células Endoteliais/ultraestrutura , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/enzimologia , Hiperlipidemias/patologia , Masculino , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuína 1/genética
18.
Appl Opt ; 58(36): 9883-9895, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31873634

RESUMO

Modulation using a rotating waveplate is the most popular way in astronomy to obtain radiation polarization states and thus the physical condition of celestial bodies. Modulation error analysis of the rotating quarter-waveplate polarimeter is presented in this paper. In terms of geometric dimensions, three modulation error sources are analyzed: the waveplate axial error, waveplate rotation axis tip-tilt error (zenithal error), and position error of the waveplate fast axis (azimuthal error). The dispersion deviation, as another dimension of modulator error, is also studied in this paper. In theory, two factors affect the accuracy of polarization measurement using waveplate polarimetry: retardance $ \delta $δand fast axis position $ \theta $θ. The temperature property of the waveplate, which represents the axial error, the waveplate mounting tip-tilt error, which represents the zenithal error, and the wavelength-based retardance characteristic, which represents the dispersion property of the waveplate, belong to the retardance error. The motorized rotary stage home position error and the random sample rotating position error, representing the azimuthal error, belong to the fast axis position error. These factors will be analyzed in detail here. Based on these analyses, the maximum allowable upper limits for each error source under $ 1 \times {10^{ - 4}} $1×10-4 polarization measurement accuracy are presented. Also, feasible solutions are proposed to address these errors.

19.
Biomed Pharmacother ; 118: 109302, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545249

RESUMO

Long non-coding RNA growth arrest-specific 5 (GAS5) has been demonstrated to be involved in the pathogenesis of atherosclerosis (AS). The purpose of the present study was to investigate the underlying mechanisms of GAS5 on the inflammation and lipid metabolic disorders of AS. ApoE-/- mice were fed on a high fat diet (HFD) and THP-1 macrophages were treated with ox-LDL to construct AS model in vivo and in vitro, respectively. The detections of blood lipids and inflammatory cytokines were performed using corresponding assay kits. qRT-PCR was used to assess the expression of GAS5 and miR-135a. Western blot was performed to detect PPARα and CPT1 levels. The targeted interaction between GAS5 and miR-135a was determined by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our data revealed that GAS5 was upregulated in AS mice model and ox-LDL-treated macrophages. GAS5 silencing alleviated lipid metabolic disorders and inflammation in AS mice and ox-LDL-treated macrophages. Moreover, GAS5 directly targeted miR-135a and repressed miR-135a expression. MiR-135a expression restoration abrogated the alleviative effects of GAS5 silencing on inflammation and lipid metabolic disorders in ox-LDL-treated macrophages. In conclusion, our study suggested that GAS5 silencing repressed the malignant progression of AS at least partly through upregulation of miR-135a. Targeting GAS5 might be a promising treatment strategy for AS management.


Assuntos
Aterosclerose/genética , Aterosclerose/patologia , Inativação Gênica , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Regulação para Cima/genética , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Sequência de Bases , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Humanos , Inflamação/patologia , Metabolismo dos Lipídeos , Lipoproteínas LDL/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Modelos Biológicos , RNA Longo não Codificante/genética , Células THP-1
20.
J Biomed Nanotechnol ; 15(6): 1213-1222, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31072429

RESUMO

The development of effective treatment for the infection and bone defect resulting from advanced osteomyelitis is an urgent task in the orthopedic clinic. To simultaneously address the issues of infection and bone defect, the multifunctional electrospun scaffolds composed of polylactide (PLA), nano-hydroxyapatite-graft-polylactide (nHA-g-PLA), and antibiotic vancomycin (VAN) were developed for the treatment of advanced osteomyelitis in the present study. The composite scaffolds PLA/nHA/VAN could sustainably release VAN and exhibited excellent antibacterial activity toward S. aureus. The rough surface of PLA/nHA/VAN induced by the presence of nHA-g-PLA promoted the adhesion and proliferation of osteoblasts. More interestingly, PLA/nHA/VAN, especially PLA/nHA10/VAN8, reduced bone infections and boosted bone regeneration at the defect site with better outcomes than other treatment groups. In conclusion, it has been demonstrated to be highly effective for the treatment of osteomyelitis using the scaffolds with sustained release properties, which has great potential for real application in the orthopedic clinic.


Assuntos
Osteomielite , Alicerces Teciduais , Durapatita , Humanos , Nanoestruturas , Poliésteres , Staphylococcus aureus
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