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1.
J Acoust Soc Am ; 155(5): 3132-3143, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38727550

RESUMO

The study of transient acoustic wave propagation across the Arctic Ocean ice layer provides theoretical guidance for the design of trans-ice acoustic communication systems. In this study, the Arctic Ocean was modeled as an ice-water composite structure, where the ice and water are regarded as an elastic solid and liquid, respectively. An analytical transient solution for acoustic wave propagation in this structure was derived using the eigenfunction expansion method. Further, the numerical procedures were presented and used to analyze the acoustic wave propagation characteristics across the ice layer. The results show that waveforms corresponding to the radial displacements are more severely distorted than the axial displacements. The amplitudes of the radial and axial displacements decreased rapidly with increasing propagation distance. The ice thickness had a greater impact on the radial displacement than axial displacement; the thicker the ice, the greater the distortion for both radial and axial displacements.

2.
Aging (Albany NY) ; 15(15): 7476-7495, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37535001

RESUMO

SET binding protein 1 (SETBP1) plays crucial roles in various biological processes; however, its involvement in cancer immune checkpoint inhibitor (ICI) treatments has never been studied. In this study, we collected a total of 631 melanoma and 109 non-small cell lung cancer (NSCLC) samples treated with ICI agents (i.e., anti-CTLA-4, anti-PD-1/PD-L1, or combination therapy). Additionally, we obtained their corresponding somatic mutational profiles. We observed that SETBP1 mutated (SETBP1-MUT) melanoma patients exhibited significantly prolonged ICI survival outcomes compared to wild-type patients (HR: 0.56, 95% CI: 0.38-0.81, P = 0.002). Consistently, an elevated ICI response rate was also noticed in the SETBP1-MUT group (42.9% vs. 29.1%, P = 0.016). The Association of SETBP1 mutations with favorable immunotherapeutic prognosis and response was further supported by an independent NSCLC cohort (both P < 0.05). Additional immunological analyses revealed that favorable immune infiltration, tumor immunogenicity, and immune response circuits were enriched in SETBP1-MUT patients. Overall, our findings suggest that SETBP1 mutations may serve as a new biomarker for stratifying beneficiaries of ICI treatments in melanoma and NSCLC, which provides possible evidence for tailoring clinical immunotherapeutic strategies.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Melanoma , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Antineoplásicos Imunológicos/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Proteínas de Transporte/genética , Proteínas Nucleares/genética
3.
Toxicon ; 230: 107174, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37236550

RESUMO

Steroid-induced avascular necrosis of femoral head (SANFH) is one of the most common complications caused by long-term or excessive clinical use of glucocorticoids. This study aimed to investigate the effects of dried root of Rehmannia glutinosa extracts (DRGE) in SANFH. First, SANFH rat model was established by dexamethasone (Dex). Tissue change and proportion of empty lacunae were detected by hematoxylin and eosin staining. Protein levels were detected by western bloting analysis. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed to assess apoptosis of femoral head tissue. Cell viability and apoptosis of MC3T3-E1 cells were assessed by Cell Counting Kit-8 assay and flow cytometry. ALP activity and cell mineralization were detected by ALP staining assay and Alizarin red staining. The findings showed that DRGE improved tissue damage, inhibited apoptosis, and promoted osteogenesis in SANFH rats. In vitro, DRGE increased cell viability, inhibited cell apoptosis, promoted osteoblast differentiation, reduced the levels of p-GSK-3ß/GSK-3ß, but increased the levels of ß-catenin in cells treated with Dex. Furthermore, DKK-1, an inhibitor of the wingless-type (Wnt)/ß-catenin signaling pathway, reversed the effect of DRGE on cell apoptosis and ALP activity in cells treated with Dex. In conclusion, DRGE prevents SANFH by activating the Wnt/ß-catenin signaling pathway, indicating that DRGE may be a hopeful choice drug to prevent and treat patients with SANFH.


Assuntos
Necrose da Cabeça do Fêmur , Extratos Vegetais , Rehmannia , Animais , Ratos , beta Catenina/metabolismo , Cabeça do Fêmur/metabolismo , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/tratamento farmacológico , Necrose da Cabeça do Fêmur/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Osteogênese , Rehmannia/química , Transdução de Sinais , Esteroides/efeitos adversos , Extratos Vegetais/farmacologia
4.
Oncol Lett ; 24(5): 388, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36276499

RESUMO

The aim of this study was to investigate the potential mechanisms of long noncoding (lnc) RNA Just proximal to X-inactive specific transcript (JPX) in interleukin (IL)-1ß-stimulated chondrocytes. Human C28/I2 chondrocytes were treated with IL-1ß to simulate osteoarthritic (OA) injury. The expression levels of JPX, microRNA (miRNA/miR)-25-3p, and peptidylprolyl isomerase D (PPID) were measured using reverse transcription-quantitative PCR or western blotting. The IL-1ß-stimulated injury was assessed using a Cell Counting Kit-8 assay, flow cytometry, and western blot analysis. The targeted relationship between miR-25-3p, JPX, and PPID was verified using a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The results showed that JPX expression was upregulated in OA patients and IL-1ß-stimulated chondrocytes. JPX knockdown enhanced cell viability and suppressed apoptosis of IL-1ß-stimulated chondrocytes. miR-25-3p inhibition rescued the inhibitory effect of JPX knockdown on IL-1ß-stimulated injury. PPID overexpression eliminated the effects of JPX knockdown on IL-1ß-stimulated chondrocytes. In conclusion, JPX knockdown increased cell viability and reduced apoptosis in IL-1ß-stimulated chondrocytes, and this involved modulation of a miR-25-3p/PPID axis.

5.
Zool Stud ; 60: e64, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35665089

RESUMO

The inner ears of fish contain three pairs of otoliths-lapilli, asterisci and sagittae-which play important roles in hearing and balance. However, acoustic properties and dynamic responses of fish otoliths are poorly understood. The large yellow croaker (Larimichthys crocea), like many species in the family Sciaenidae, is extremely sensitive to sound. The present study used L. crocea sagittae as the research subject and examined the variation in shear stress on sagittae under different acoustic stimuli. For the first time, the sound speed of the sagitta was measured using ultrasonic pulse-echo techniques, and the acoustic impedance and natural frequency of the sagitta were calculated. Larimichthys crocea adults (20-22 cm standard length, n = 10) had a sagitta density of 2781.5 ± 28.06 kg/m3, sound speed of 4828-6000 m/s and acoustic impedance range of 13.4-16.7 MPa·s/m, approximately 9-11 times that of seawater (1.48 MPa·s/m). The natural frequency of the sagitta was 76.4-95.5 kHz. The shape and structural details of sagittae were reconstructed by 3D scanner and the shear stress responses of sagittae under different acoustic stimulus were investigated based on a finite element model. The simulation results showed that the shear stress responses tended to increase and then decrease in the range of sciaenid hearing frequency from 200 to 1300 Hz, peaking at 800 Hz. The shear stress responses varied with the direction of acoustic stimulus and peaked when the incident direction was perpendicular to the inner surface of the otolith. These results provide important parameters that may be used to protect L. crocea from possible underwater noise damage, particularly during their spawning aggregations and over-wintering aggregations.

6.
Brain Behav ; 9(10): e01400, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31486271

RESUMO

BACKGROUND: Peripheral nerve injury (PNI) causes motor and sensory defects, has strong impact on life quality and still has no effective therapy. Miconazole is one of the most widely used antifungal drugs; the aims of the study were to investigate the effects of miconazole during sciatic nerve regeneration in a mouse model of sciatic nerve crush injury. METHODS: We established peripheral nerve crush model and investigated the effects of miconazole by multiple aspects. We further studied the potential mechanism of action of miconazole by Western blotting, fluorescence immunohistochemistry, and PCR analysis. RESULTS: Miconazole improves the symptoms of crushed nerve by improving inflammatory cell infiltration and demyelinating myelin of sciatic nerve. Affected by miconazole, the proportion of inflammatory M1 macrophages in the distal part of the sciatic nerve was reduced, and the proportion of anti-inflammatory M2 macrophages was increased. Finally, the neuroprotective properties of miconazole may be regulated by the nuclear factor (NF)-κB pathway. CONCLUSIONS: Our data suggest that miconazole can effectively alleviate PNI, and the mechanism involves mediating a phenotype change of M1/ M2 macrophages. Thus, miconazole may represent a potential therapeutic intervention for nerve crush injury.


Assuntos
Lesões por Esmagamento/tratamento farmacológico , Miconazol/farmacologia , NF-kappa B/efeitos dos fármacos , Traumatismos dos Nervos Periféricos/tratamento farmacológico , Animais , Inibidores do Citocromo P-450 CYP2C9/farmacologia , Modelos Animais de Doenças , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Compressão Nervosa , Regeneração Nervosa/fisiologia , Fenótipo , Nervo Isquiático/lesões
7.
J Alloys Compd ; 714: 20-25, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29056824

RESUMO

Resonant ultrasound spectroscopy (RUS) was used to determine the temperature dependence of full matrix material constants of PZT-8 piezoceramics from room temperature to 100 °C. Property variations from sample to samples can be eliminated by using only one sample, so that data self-consistency can be guaranteed. The RUS measurement system error was estimated to be lower than 2.35%. The obtained full matrix material constants at different temperatures all have excellent self-consistency, which can help accurately predict device performance at high temperatures using finite element simulations.

8.
J Vis Exp ; (110)2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27168336

RESUMO

During the operation of high power electromechanical devices, a temperature rise is unavoidable due to mechanical and electrical losses, causing the degradation of device performance. In order to evaluate such degradations using computer simulations, full matrix material properties at elevated temperatures are needed as inputs. It is extremely difficult to measure such data for ferroelectric materials due to their strong anisotropic nature and property variation among samples of different geometries. Because the degree of depolarization is boundary condition dependent, data obtained by the IEEE (Institute of Electrical and Electronics Engineers) impedance resonance technique, which requires several samples with drastically different geometries, usually lack self-consistency. The resonant ultrasound spectroscopy (RUS) technique allows the full set material constants to be measured using only one sample, which can eliminate errors caused by sample to sample variation. A detailed RUS procedure is demonstrated here using a lead zirconate titanate (PZT-4) piezoceramic sample. In the example, the complete set of material constants was measured from room temperature to 120 °C. Measured free dielectric constants and  were compared with calculated ones based on the measured full set data, and piezoelectric constants d15 and d33 were also calculated using different formulas. Excellent agreement was found in the entire range of temperatures, which confirmed the self-consistency of the data set obtained by the RUS.


Assuntos
Ultrassonografia/instrumentação , Ultrassonografia/métodos , Cerâmica/química , Simulação por Computador , Chumbo/química , Temperatura , Titânio/química , Zircônio/química
9.
Appl Phys Lett ; 108(8): 082901, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26957649

RESUMO

In order to simulate the performance of electromechanical devices at elevated temperatures, full tensor properties of piezoelectric materials at high temperatures are needed. Such data are extremely difficult to get for relaxor-based single crystals because their properties are determined by domain structures, which are strongly geometry dependent. We report here the temperature dependence of full tensor material constants of [001]c poled Mn-doped 0.24Pb(In1/2Nb1/2)O3-0.46Pb(Mg1/3Nb2/3)O3-0.30PbTiO3 single crystals from 25 °C to 55 °C, which were determined by the resonant ultrasound spectroscopy. Because only one sample was used, high degree of self-consistency was achieved for the tensor constants at all measured temperatures.

10.
Appl Phys Lett ; 106(5): 052902, 2015 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-25713470

RESUMO

Up to date, there are no self-consistent data in the literature on the temperature dependence of full matrix material properties for piezoelectric materials because they are extremely difficult to determine. Using only one sample, we have measured the temperature dependence of full matrix constants of lead zirconate titanate (PZT-4) from room temperature to 120 °C by resonant ultrasound spectroscopy. Self-consistency is guaranteed here because all data at different temperatures come from one sample. Such temperature dependence data would make it a reality to accurately predict device performance at high temperatures using computer simulations.

11.
Artigo em Inglês | MEDLINE | ID: mdl-22899122

RESUMO

The objective of this study is to investigate the three-dimensional (3-D) analytical solution for transient guided wave propagation in liquid-filled pipe systems using the eigenfunction expansion method (EEM). The eigenfunctions corresponding to finite liquid-filled pipe systems with a traction-free lateral boundary and rigid smooth end boundaries are obtained. Additionally, the orthogonality of the eigenfunctions is proved in detail. Subsequently, the exact 3-D analytical transient response of finite liquid-filled pipe systems to external body forces is constructed using the EEM, based on which, the approximate 3-D analytical transient response of the systems to external surface forces is derived. Furthermore, the analytical solution for transient guided wave propagation in finite liquid-filled pipe systems is extended explicitly and concisely to infinite liquid-filled pipe systems. Several numerical examples are given to illustrate the analysis of the spatial and frequency distributions of the radial and axial displacement amplitudes of various guided wave modes; the numerical examples also simulate the transient displacement of the pipe wall and the transient pressure of the internal liquid from the present solution. The present solution can provide some theoretical guidelines for the guided wave nondestructive evaluation of liquid-filled pipes and the guided wave technique for downhole data transfer.

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