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1.
Sensors (Basel) ; 24(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38794038

RESUMO

The U-shaped fiber configuration represents the elementary form of micro-displacement sensing, characterized by its exceptional freedom and flexibility. The study proposes the U-shaped bent single-mode-multimode-single-mode (SMS) fiber structure that integrates the multimode interference (MMI) effect for enhanced mode dispersion and the Mach-Zönder interference (MZI) effect for spectral sensitivity improvement. The transmission spectral properties of the U-shaped SMS fiber structure with a bent radius over 1 cm are experimentally measured as the change in displacement varied within the range of 5 mm in this work. As the radius decreases, the spectrum shows redshift, which is related to the central wavelength of the peak or dips-a smaller wavelength results in a stronger redshift for the same displacement change. The average sensitivity of micro-displacement measurement within a range of 5 mm is 5.41 pm/µm, and the linearity is 99.62%. The maximum sensitivity of U-shaped SMS fiber structure is 34.46 pm/µm, with the minimum displacement change of approximately 5.804 nm. The transmission spectral properties of the U-shaped SMS fiber structure within the ranges of 50 µm, 500 µm, and 5 mm are experimentally measured in this work. This experiment observed a relatively uniform spectral drift pattern in a large range of micro-displacement sensing. The measurement range is limited by the limited spectral range of the light source and the discontinuous variation in the effective refractive index. This provides an experimental reference for further understanding the characteristics of U-shaped fiber structures and applying its application in micro-displacement sensing.

2.
Opt Lett ; 49(3): 518-521, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300048

RESUMO

We designed a broadband lens along with a graphene/silicon photodiode for wide spectral imaging ranging from ultraviolet to near-infrared wavelengths. By using five spherical glass lenses, the broadband lens, with the modulation transfer function of 0.38 at 100 lp/mm, corrects aberrations ranging from 340 to 1700 nm. Our design also includes a broadband graphene/silicon Schottky photodiode with the highest responsivity of 0.63 A/W ranging from ultraviolet to near-infrared. By using the proposed broadband lens and the broadband graphene/silicon photodiode, several single-pixel imaging designs in ultraviolet, visible, and near-infrared wavelengths are demonstrated. Experimental results show the advantages of integrating the lens with the photodiode and the potential to realize broadband imaging with a single set of lens and a detector.

3.
Chemosphere ; 339: 139610, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37482311

RESUMO

Because of the potential environmental harm caused by the extensive application of tetracycline (TC), this study used jasmine waste rich in organic matter as a precursor and one-step carbonization into metal-free carbon-based materials to efficiently activate peroxymonosulfate (PMS) toward degrading TC. The jasmine waste biochar (JWB) with a heating rate of 10 °C min-1 and a heating temperature of 700 °C was selected as the most suitable material based on its catalytic performance. The effects of catalyst dose, PMS dose, initial pH value, coexisting inorganic anions and TC concentration on the JWB/PMS/TC system were thoroughly optimized. The results showed that the degradation efficiency of TC by JWB/PMS system was 90%. Meanwhile, the combination of electron paramagnetic resonance, masking experiments and X-ray photoelectron spectrometry confirmed that JWB degraded TC mainly through the non-radical radical pathway of 1O2 oxidation and mediated the electron transfer to PMS. In addition, some degradation products were analyzed by LC-MS and possible degradation pathways of the system were proposed. Therefore, this paper proposes a novel method for recycling jasmine waste and providing a low-cost catalyst for the oxidation treatment of refractory organic matter.


Assuntos
Compostos Heterocíclicos , Jasminum , Sulfatos , Tetraciclina , Antibacterianos , Peróxidos
4.
Opt Express ; 30(13): 23217-23226, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225007

RESUMO

Chiral structures have a wide range of applications, such as biometric identification, chemical analysis, and chiral sensing. The simple fabrication process of chiral nanostructures that can produce a significant circular dichroism (CD) effect remains a challenge. Here, a three-dimensional (3D) cantilever-shaped nanostructure, which inherits the chiral advantages of 3D nanostructures and simplicity of 2D nanostructures, is proposed. The nanostructure can be prepared by the combination of one-time electron beam lithography and oblique-angle deposition and consists of a thin metal film with periodic holes such that two hanging arms were attached to the edges of holes. The length of the cantilever and the height difference between the two arms can be adjusted by controlling the tilt angle of beam current during the deposition processes. Numerical calculations showed that the enhancement of CD signal was achieved by plasmon distortion on the metal film by the lower hanging part of the cantilever structure. Furthermore, signals can be actively adjusted using a temperature-sensitive polydimethylsiloxane (PDMS) material. The angle between the lower cantilever and the top metal film was regulated by the change in PDMS volume with temperature. The results provide a new way to fabricating 3D nanostructures and a new mechanism to enhance the CD signal. The proposed nanostructure may have potential applications, such as in ultra-sensitive detection and remote temperature readout, and is expected to be an ultra-compact detection tool for nanoscale structural and functional information.

5.
mBio ; 13(3): e0069922, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35420479

RESUMO

Although the phosphorothioate (PT) modification, in which the nonbridging oxygen in the DNA sugar-phosphate backbone is replaced by sulfur, has been reported to play versatile roles in multiple cellular processes, very little data have been obtained to define the role of PT in epigenetic regulation. In this study, we report that the PT system in Salmonella enterica serovar Cerro 87 is involved in the transcriptional regulation of the torCAD operon encoding the trimethylamine N-oxide (TMAO) respiration machinery that enables the use of TMAO as a terminal electron acceptor for respiration when oxygen is not available. In vitro, PT enhanced the binding of the transcriptional activator of the torCAD operon, namely, TorR, to its DNA substrate (tor boxes). However, in vivo, the PT modification protein complex DndCDE downregulated torCAD transcription through competing with the binding of TorR to the tor boxes. The altered expression of torCAD caused by PT modification proteins affected cell growth that relied on TMAO respiration. To our knowledge, this is the first report supporting that PT proteins participate in transcriptional regulation, showing a new function of PT systems. IMPORTANCE Since the initial discovery of DNA phosphorothioate (PT) modification systems in Streptomyces lividans in the 1980s, explorations of the biological functions of DNA PT systems have advanced and yielded a number of important findings. However, the functions of PT systems, especially in genetic regulation, remain largely unknown. In this study, we report a case in which the PT system participates in the transcriptional regulation of the torCAD operon in Salmonella enterica serovar Cerro 87. While the PT modification enhanced the binding of TorR, the torCAD operon transcriptional activator, to its DNA substrate in vitro, we found that the PT modification protein complex DndCDE directly competed with TorR binding in vivo and subsequently repressed the expression of torCAD and attenuated cell growth that relied on TMAO respiration. These findings provide a deeper understanding of the characteristics of the PT chemical structure and broaden our understanding of the mechanisms by which PT regulates gene expression.


Assuntos
Metilaminas , Salmonella enterica , Anaerobiose , Proteínas de Bactérias/metabolismo , DNA/metabolismo , Epigênese Genética , Metilaminas/metabolismo , Oxigênio/metabolismo , Respiração , Salmonella enterica/genética , Salmonella enterica/metabolismo , Fatores de Transcrição/metabolismo
6.
Am J Physiol Renal Physiol ; 322(5): F512-F526, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35253468

RESUMO

Injury-induced fibroblast-to-myofibroblast differentiation is a key event of renal fibrosis. Yes-associated protein (YAP), a transcriptional coactivator, plays an important role in fibroblast activation and Smad transcriptional activity to promote transforming growth factor-ß (TGF-ß)-induced differentiation from fibroblasts to myofibrolasts. Macrophage stimulating 1/2 (MST1/2), a negative regulator of YAP, also increases in fibroblasts by TGF-ß stimulation. Here, we examined whether MST1/2, as a negative regulator, attenuated YAP and TGF-ß/Smad signaling in fibroblasts to reduce fibrosis. MST1/2 and YAP expression levels increased in platelet-derived growth factor receptor-α (PDGFRα)+ cells of obstructed kidneys following the increase of TGF-ß and renal fibrosis after unilateral ureteral obstruction. PDGFRα+ cell-specific knockout of Mst1/2 in mice increased unilateral ureteral obstruction-induced myofibroblast accumulation and fibrosis. In cultured fibroblasts, TGF-ß increased YAP and promoted its nucleus entry, but a high dose and prolonged treatment of TGF-ß increased the MST1/2 activation to prevent YAP from entering the nucleus. Our results indicate that MST1/2 is a negative feedback signal of TGF-ß-induced fibroblast differentiation.NEW & NOTEWORTHY Using a mouse model with macrophage stimulating 1/2 (Mst1/2) double knockout in PDGFRα+ cells and an MST1/2 inhibitor, we demonstrated that MST1/2 acted as a negative feedback signal of transforming growth factor-ß-induced fibroblast differentiation. Furthermore, we demonstrated that Hippo-MST as a negative feedback signal can decrease the renal fibrosis process. This finding contributes to our understanding of the mechanism of coregulated renal remodeling after injury.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Rim , Miofibroblastos , Proteínas Serina-Treonina Quinases , Serina-Treonina Quinase 3 , Fibroblastos/metabolismo , Fibrose , Fator de Crescimento de Hepatócito , Via de Sinalização Hippo , Humanos , Rim/patologia , Macrófagos/metabolismo , Miofibroblastos/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
7.
Appl Opt ; 60(23): 6742-6747, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613151

RESUMO

Circular dichroism (CD) demonstrates broad application prospects in enantioselective catalysis, chiral separation, and ultrasensitive detection. Increasing the CD intensity of easily fabricated plasmonic nanostructures will promote the application of these artificial nanostructures. A chiral plasmonic system that consists of two unaligned nanorods and a metal film is proposed in this study to achieve a large CD effect. Indirect coupling of a nanorod-film-nanorod in the proposed chiral plasmonic system generates a larger CD intensity compared to the direct coupling of a nanorod-nanorod. In addition, the effects of structural parameters on the CD effect of the proposed system are numerically investigated. Results showed that the indirect coupling is strongly dependent on the separation between the nanorod and the metal film. The results of this study can provide an effective strategy to enhance the CD effect of plasmonic chiral systems.

8.
J Environ Manage ; 298: 113473, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34358937

RESUMO

For the first time, spent Zn-MnO2 primary batteries are recycled to directly build rechargeable Zn-MnO2 batteries with a mixed solution of sulfuric acid and hydrogen peroxide as the leachate, which aimed to the efficient recovery of spent Zn-MnO2 primary batteries and the realization of high-powered rechargeable Zn-MnO2 batteries. After simple purification, the leached liquid is directly used as the working solution to prepare an electrolytic rechargeable Zn-MnO2 battery. The experimental results show that the performance of the recycling solution of the neutral Zn-MnO2 primary battery was better than that of the alkaline Zn-MnO2 primary battery, and both performed better than the solution prepared with chemically pure reagents. After optimizing the pH of the working solution and charging current, the obtained rechargeable Zn-MnO2 battery can provide an energy efficiency of 72.33 % ± 0.55, a coulombic efficiency of 90.17 % ± 0.71, and excellent cycle stability. These experimental results show that spent Zn-MnO2 primary batteries can be successfully recycled to prepare rechargeable Zn-MnO2 batteries, demonstrating very good application potential.


Assuntos
Compostos de Manganês , Zinco , Fontes de Energia Elétrica , Óxidos , Reciclagem
9.
Front Chem ; 9: 646218, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732687

RESUMO

A high energy efficiency, low charging voltage cathode is of great significance for the development of non-aqueous lithium-oxygen batteries. Non-stoichiometric manganese dioxide (MnO2-x) and chromium trioxide (Cr2O3) are known to have good catalytic activities for the discharging and charging processes, respectively. In this work, we prepared a cathode based on Cr2O3 decorated MnO2-x nanosheets via a simple anodic electrodeposition-electrostatic adsorption-calcination process. This combined fabrication process allowed the simultaneous introduction of abundant oxygen vacancies and trivalent manganese into the MnO2-x nanosheets, with a uniform load of a small amount of Cr2O3 on the surface of the MnO2-x nanosheets. Therefore, the Cr2O3/MnO2-x electrode exhibited a high catalytic effect for both discharging and charging, while providing high energy efficiency and low charge voltage. Experimental results show that the as-prepared Cr2O3/MnO2-x cathode could provide a specific capacity of 6,779 mA·h·g-1 with a terminal charge voltage of 3.84 V, and energy efficiency of 78%, at a current density of 200 mA·g-1. The Cr2O3/MnO2-x electrode also showed good rate capability and cycle stability. All the results suggest that the as-prepared Cr2O3/MnO2-x nanosheet electrode has great prospects in non-aqueous lithium-oxygen batteries.

10.
Nanoscale Res Lett ; 15(1): 122, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32458218

RESUMO

Polyethylene oxide (PEO)-based solid polymer electrolyte (SPE) is considered to have great application prospects in all-solid-state li-ion batteries. However, the application of PEO-based SPEs is hindered by the relatively low ionic conductivity, which strongly depends on its crystallinity and density of grain boundaries. In this work, a simple and effective press-rolling method is applied to reduce the crystallinity of PEO-based SPEs for the first time. With the rolled PEO-based SPE, the LiFePO4/SPE/Li all-solid li-ion battery delivers a superior rechargeable specific capacity of 162.6 mAh g-1 with a discharge-charge voltage gap of 60 mV at a current density of 0.2 C with a much lower capacity decay rate. The improvement of electrochemical properties can be attributed to the press-rolling method, leading to a doubling conductivity and reduced activation energy compared with that of electrolyte prepared by traditional cast method. The present work provides an effective and easy-to-use grain reforming method for SPE, worthy of future application.

11.
RSC Adv ; 10(26): 15650-15655, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35495472

RESUMO

Small Ag nanoparticles are well dispersed onto graphene sheets via a simple and environmentally friendly route using disposable paper-cups. The obtained Ag/graphene materials exhibit much higher catalytic activity for the oxygen reduction reaction than the conventional Ag/graphene catalyst does in alkaline media.

12.
Int J Mol Sci ; 20(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480213

RESUMO

Cafestol and kahweol are natural diterpenes extracted from coffee beans. In addition to the effect of raising serum lipid, in vitro and in vivo experimental results have revealed that the two diterpenes demonstrate multiple potential pharmacological actions such as anti-inflammation, hepatoprotective, anti-cancer, anti-diabetic, and anti-osteoclastogenesis activities. The most relevant mechanisms involved are down-regulating inflammation mediators, increasing glutathione (GSH), inducing apoptosis of tumor cells and anti-angiogenesis. Cafestol and kahweol show similar biological activities but not exactly the same, which might due to the presence of one conjugated double bond on the furan ring of the latter. This review aims to summarize the pharmacological properties and the underlying mechanisms of cafestol-type diterpenoids, which show their potential as functional food and multi-target alternative medicine.


Assuntos
Diterpenos/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Diterpenos/química , Humanos , Hipoglicemiantes/farmacologia
13.
Circ J ; 82(9): 2332-2341, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-29998929

RESUMO

BACKGROUND: In a previous study, a low level of miR-126-3p in endothelial progenitor cells (EPCs) was linked to the outcome of ischemic cardiomyopathy (ICM) patients. However, it remains unclear whether transplantation with miR-126-3p-overexpressing EPCs (MO-EPCs) can improve the cardiac function of ICM animal models. Methods and Results: miR-126-3p overexpression by lentiviral vector significantly increased migration and tube-like structures of EPCs from ICM patients. MO-EPCs or non-modified EPCs (NM-EPCs) were transplanted into nude rats with ICM induced by coronary artery ligation. MO-EPC transplantation increased capillary density and EPC survival rate in myocardial tissues of nude rats. Cytokines were also assessed by antibody array and real-time RT-PCR. G-CSF, VEGF-A, IL-3, IL-10, IGF-1, angiogenin, HGF, TIMP-1 and TIMP-2 were upregulated, and IL-8, MCP-1, MCP-2, TNF-α, TNF-ß and MIP-1ß were downregulated after miR-126-3p overexpression in EPCs. The same results were obtained in infarction tissues of nude rats after MO-EPC transplantation. Eight weeks after MO-EPC transplantation, left ventricular function improved significantly with clearly decreased infarction size, increased anterior wall thickness, and inhibition of inflammation compared with the results for NM-EPC transplantation. However, MO-EPC transplantation showed no increase in survival time of nude rats with ICM during 8 weeks of observation. CONCLUSIONS: miR-126-3p can restore the biology of EPCs from ICM patients. Moreover, MO-EPC transplantation improves cardiac function effectively, representing a promising future treatment for ICM.


Assuntos
Cardiomiopatias/terapia , Células Progenitoras Endoteliais/transplante , MicroRNAs/biossíntese , Infarto do Miocárdio/terapia , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Animais , Movimento Celular , Sobrevivência Celular , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Fisiológica , Ratos , Ratos Nus
14.
Sci Rep ; 6: 20021, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26805027

RESUMO

Electrochemical performance and production cost are the main concerns for the practical application of supercapacitors. Here we report a simple and universally applicable method to prepare hybrid metal oxides by metal redox reaction utilizing the inherent reducibility of metals and oxidbility of for the first time. As an example, Ni(OH)2/MnO2 hybrid nanosheets (NMNSs) are grown for supercapacitor application by self-reaction of Ni foam substrates in KMnO4 solution at room temperature. The obtained hybrid nanosheets exhibit high specific capacitance (2,937 F g(-1)). The assembled solid-state asymmetric pseudocapacitors possess ultrahigh energy density of 91.13 Wh kg(-1) (at the power density of 750 W kg(-1)) and extraordinary cycling stability with 92.28% capacitance retention after 25,000 cycles. Co(OH)2/MnO2 and Fe2O3/MnO2 hybrid oxides are also synthesized through this metal redox mechanism. This green and low-cost method is capable of large-scale production and one-step preparation of the electrodes, holding promise for practical application of high-performance pseudocapacitors.

15.
Heart Vessels ; 30(5): 669-74, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25260401

RESUMO

The aim of this study was to explore myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs. 24 male pigs (34.6 ± 1.3 kg) were randomly divided into three groups-control group, drug therapy group, and ECMO group. Myocardial infarction model was created in drug therapy group and ECMO group by ligating coronary artery. When cardiogenic shock occurred, drugs were given in drug therapy group and ECMO began to work in ECMO group. The pigs were killed 24 h after cardiogenic shock. Compared with in drug therapy group, left ventricular end-diastolic pressure in ECMO group decreased significantly 6 h after ligation (P < 0.05). At the end of the experiments, LV - dp/dt among three groups was significantly different, drug therapy group < ECMO group < control group. There was no difference in LV + dp/dt between drug therapy group and ECMO group. Compared with drug group, myocardial infarct size of ECMO group did not reduce significantly, but myocardial enzyme and troponin-I decreased significantly. Compared with drug therapy, ECMO improves left ventricular diastolic function, and may improve systolic function. ECMO cannot reduce myocardial infarct size without revascularization, but may have positive effects on ischemic areas by avoiding further injuring.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Infarto do Miocárdio/terapia , Miocárdio/patologia , Choque Cardiogênico/terapia , Animais , Modelos Animais de Doenças , Seguimentos , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Choque Cardiogênico/etiologia , Choque Cardiogênico/fisiopatologia , Volume Sistólico/fisiologia , Suínos , Porco Miniatura , Fatores de Tempo , Função Ventricular Esquerda/fisiologia
16.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(6): 527-9, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24113050
17.
Zhonghua Yi Xue Za Zhi ; 92(44): 3104-7, 2012 Nov 27.
Artigo em Chinês | MEDLINE | ID: mdl-23328418

RESUMO

OBJECTIVE: To assess the clinical and predictive value of cardiopulmonary exercise testing (CPET) used in heart failure with normal left ventricular ejection fraction (HFNEF). METHODS: A total of 49 HFNEF patients of (New York Heart Association) NYHA class II were randomly selected from September 2010 to July 2012. The parameters of CPET and ultrasonic cardiogram (UCG) were collected at Day 3 post-admission. Person's and partial correlations were used to perform to compare CPET and UCG. RESULTS: Pearson's correlation revealed that mitral peak velocity of early filling/early diastolic mitral annular velocity (E/E', 10.14 ± 2.05) was significantly correlated with peak oxygen uptake (VO2 peak, (24.15 ± 8.31) ml×kg⁻¹×min⁻¹, r = -0.287, P = 0.046), carbon dioxide production (VCO2, (1.63 ± 0.51) L/min, r = -0.429, P = 0.002), partial pressure of end-tidal carbon dioxide (PET CO2, (39.50 ± 7.77) mm Hg, r = -0.282, P = 0.050) and minute ventilation/carbon dioxide production (VE/VCO2, 31.69 ± 5.32, r = 0.411, P = 0.003). Early diastolic mitral annular velocity (E', (6.46 ± 1.60) cm/s) was relevant to VO2 peak (r = 0.351, P = 0.013), VCO(2) (r = 0.452, P = 0.001), PET CO2 (r = 0.310, P = 0.030), VE/VCO2 (r = -0.434, P = 0.002) and respiratory exchange ratio (RER, 1.18 ± 0.13, r = 0.350, P = 0.014). After adjustment, VCO2 was correlated with E/E' (r = -0.369, P = 0.019) and E' (r = 0.393, P = 0.010). VE/VCO2 was relevant to E/E' (r = 0.414, P = 0.006) and E' (r = -0.334, P = 0.031). CONCLUSION: For HFNFE patients, CPET has high values of assessment and prognosis.


Assuntos
Ecocardiografia , Teste de Esforço , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Volume Sistólico
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