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1.
Biomed Pharmacother ; 174: 116572, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626519

RESUMO

Epigenetic regulation and mitochondrial dysfunction are essential to the progression of idiopathic pulmonary fibrosis (IPF). Curcumin (CCM) in inhibits the progression of pulmonary fibrosis by regulating the expression of specific miRNAs and pulmonary fibroblast mitochondrial function; however, the underlying mechanism is unclear. C57BL/6 mice were intratracheally injected with bleomycin (5 mg/kg) and treated with CCM (25 mg/kg body weight/3 times per week, intraperitoneal injection) for 28 days. Verhoeff-Van Gieson, Picro sirius red, and Masson's trichrome staining were used to examine the expression and distribution of collagen and elastic fibers in the lung tissue. Pulmonary fibrosis was determined using micro-computed tomography and transmission electron microscopy. Human pulmonary fibroblasts were transfected with miR-29a-3p, and RT-qPCR, immunostaining, and western blotting were performed to determine the expression of DNMT3A and extracellular matrix collagen-1 (COL1A1) and fibronectin-1 (FN1) levels. The expression of mitochondrial electron transport chain complex (MRC) and mitochondrial function were detected using western blotting and Seahorse XFp Technology. CCM in increased the expression of miR-29a-3p in the lung tissue and inhibited the DNMT3A to reduce the COL1A1 and FN1 levels leading to pulmonary extracellular matrix remodeling. In addition, CCM inhibited pulmonary fibroblasts MRC and mitochondrial function via the miR-29a-3p/DNMT3A pathway. CCM attenuates pulmonary fibrosis via the miR-29a-3p/DNMT3A axis to regulate extracellular matrix remodeling and mitochondrial function and may provide a new therapeutic intervention for preventing pulmonary fibrosis.


Assuntos
Curcumina , DNA Metiltransferase 3A , Matriz Extracelular , Fibroblastos , Camundongos Endogâmicos C57BL , MicroRNAs , Mitocôndrias , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Curcumina/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , DNA Metiltransferase 3A/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Humanos , Camundongos , Masculino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Bleomicina , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Modelos Animais de Doenças
2.
Opt Lett ; 49(5): 1289-1292, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426995

RESUMO

Spatial-spectral interferometry (SSI) is a technique used to reconstruct the electrical field of an ultrafast laser. By analyzing the spectral phase distribution, SSI provides valuable information about the optical dispersion affecting the spectral phase, which is related to the energy distribution of the laser pulses. SSI is a single-shot measurement process and has a low laser power requirement. However, the reconstruction algorithm involves numerous Fourier transform and filtering operations, which limits the applicability of SSI for real-time dispersion analysis. To address this issue, this Letter proposes a field-programmable gate array (FPGA)-based deep neural network to accelerate the spectral phase reconstruction and dispersion estimation process. The results show that the analysis time is improved from 124 to 9.27 ms, which represents a 13.4-fold improvement on the standard Fourier transform-based reconstruction algorithm.

3.
Chemistry ; 29(67): e202302466, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37792566

RESUMO

Hybrid organic-inorganic molecules have recently received great interest due to their unique properties, which give access to their implementation in biological and material sciences. Herein, a new synthetic approach for the direct-linkage of the purely inorganic dodecaborate cluster to organic building blocks through B-C bond is established, using boronic acids as functional groups on the organic moiety, reacting under Suzuki-Miyaura coupling conditions with iodo-undecahydridododecaborate. The choices of ligand (DavePhos) and solvent (N-methylpyrrolidone for electron-poor, CD3 CN for electron-rich groups) are essential for the successful coupling. Ultimately, the newly described methodology is found to be functional-group tolerant covering a wide spectrum of substrates including electron-poor arenes.

4.
Molecules ; 28(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37050008

RESUMO

Cross-coupling reactions with [B12H11I]2- as one partner have been used successfully for Kumada and Buchwald Hartwig couplings with Pd catalysis. Here, we found that the iodide could be substituted easily, and unexpectedly, with other halides such as Br and Cl, and with pseudohalides such as cyanide, azide, and isocyanate. We found that for Cl, Br, N3, and NCO, tetrabutylammonium salts-or sodium salts-were successful halide sources, whereas for cyanide, CuCN was the only halide source that allowed a successful exchange. The azide could be reacted further in a click reaction with triazoles. While no substitution with fluoride occurred, tetrabutylammonium fluoride in the presence of water led to [B12H11OH]2-. Yields were high to very high, and reaction times were short when using a microwave oven as a heating source.

5.
Rev Sci Instrum ; 94(3): 035008, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37012794

RESUMO

Ultrafast lasers concentrate the energy in a short pulse with a duration of several tens to hundreds of femtoseconds. The resulting high peak power induces various nonlinear optical phenomena that find use in many different fields. However, in practical applications, the optical dispersion broadens the laser pulse width and spreads the energy in time, thereby reducing the peak power. Accordingly, the present study develops a piezo bender-based pulse compressor to compensate for this dispersion effect and restore the laser pulse width. The piezo bender has a rapid response time and a large deformation capacity and thus provides a highly effective means of performing dispersion compensation. However, due to hysteresis and creep effects, the piezo bender is unable to maintain a stable shape over time and hence the compensation effect is gradually degraded. To address this problem, this study further proposes a single-shot modified laterally sampled laser interferometer to estimate the parabolic shape of the piezo bender. The curvature variation of the bender is then sent as a feedback signal to a closed-loop controller to restore the bender to the desired shape. It is shown that the steady-state error of the converged group delay dispersion is around 530 fs2. Moreover, the ultrashort laser pulse is compressed from 1620 fs in the original condition to 140 fs in the compressed condition, corresponding to a 12-fold improvement.

6.
Opt Express ; 30(15): 26492-26503, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236840

RESUMO

The optical dispersion effect in ultrafast pulse laser systems broadens the laser pulse duration and reduces the theoretical peak power. The present study proposes an adaptive ultrashort pulse compressor for compensating the optical dispersion using a direct optical-dispersion estimation by spectrogram (DOES) method. The DOES has fast and accurate computation time which is suitable for real time controller design. In the proposed approach, the group delay dispersion (GDD) and its polarity are estimated directly from the delay marginal of the trace obtained from a single-shot frequency-resolved optical gating (FROG). The estimated GDD is then processed by a closed-loop controller, which generates a command signal to drive a linear deformable mirror as required to achieve the desired laser pulse compression. The dispersion analysis, control computation, and deformable mirror control processes are implemented on a single field programmable gate array (FPGA). It is shown that the DOES dispersion computation process requires just 0.5 ms to complete. Moreover, the proposed pulse compressor compensates for both static dispersion and dynamic dispersion within five time steps when closed-loop controller is performed at a frequency of 100 Hz. The experimental results show that the proposed pulse compressor yields an effective fluorescence intensity improvement in a multiphoton excited fluorescence microscope (MPEFM).

7.
Rev Sci Instrum ; 92(11): 113702, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852563

RESUMO

In ultrashort pulse laser applications, optical dispersion seriously affects the energy concentration in the laser pulse duration and lowers the peak power. Accordingly, this study proposes a rapid dispersion estimation mechanism to facilitate the compensation of optical dispersion using a closed-loop control system. In the proposed approach, the optical dispersion information of the laser pulse is estimated directly from a frequency-resolved optical gating trace without the need for an iterative pulse-retrieval algorithm. In particular, the group delay dispersion (GDD) is determined from frequency and delay marginals, which are related to the laser spectrum and intensity autocorrelation, respectively, using a simple lookup table approach. The accuracy of the estimated GDD results is confirmed via a comparison with the spectral phase distribution of the electric field reconstructed using the principal component generalized projections algorithm. It is shown that the computation time of the proposed direct estimation method is around 13 times faster than that of the traditional iterative algorithm. It thus provides a feasible approach for enabling the real-time compensation of ultrafast laser pulse compression. Moreover, in a multiphoton-excited fluorescence imaging application, the proposed pulse compression mechanism yields an effective improvement in the intensity and contrast of the reconstructed image due to the increased nonlinear optical excitation efficiency of the optimized laser pulses.

8.
Opt Express ; 29(14): 21129-21142, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265906

RESUMO

Adaptive optics (AO) is an effective technique for compensating the aberrations in optical systems and restoring their performance for various applications such as image formation, laser processing, and beam shaping. To reduce the controller complexity and extend the compensation capacity from static aberrations to dynamic disturbances, the present study proposes an AO system consisting of a self-built Shack-Hartmann wavefront sensor (SHWS), a deformable mirror (DM), and field programmable gate array (FPGA)-based controllers. This AO system is developed for tracking static and dynamic disturbances and tuning the controller parameters as required to achieve rapid compensation of the incoming wavefront. In the proposed system, the FPGA estimates the coefficients of the eight Zernike modes based on the SHWS with CameraLink operated at 200 Hz. The estimated coefficients are then processed by eight parallel independent discrete controllers to generate the voltage vectors to drive the DM to compensate the aberrations. To have the DM model for controller design, the voltage vectors are identified offline and are optimized by closed-loop controllers. Furthermore, the controller parameters are tuned dynamically in accordance with the main frequency of the aberration as determined by a fast Fourier transform (FFT) process. The experimental results show that the AO system provides a low complexity and effective means of compensating both static aberrations and dynamic disturbance up to 20 Hz.

9.
Interact Cardiovasc Thorac Surg ; 12(3): 389-93, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21172947

RESUMO

We aimed to analyse the outcomes of the deployment of extracorporeal membrane oxygenation assisted cardiopulmonary resuscitation (E-CPR) 11 times for acute myocardial infarction (AMI) in 10 adult patients at a very low-volume (VLV) centre, where perfusionists or surgeons are not always available. We conducted a three-year retrospective chart review. E-CPR was performed 13 times in 12 adult patients who had cardiac arrest events and who underwent conventional CPR for longer than 10 min. We excluded other aetiologies that led to E-CPR. All 11 selected episodes of E-CPR were diagnosed as AMI. Seven patients (63.6%) were successfully weaned off extracorporeal membrane oxygenation (ECMO). Four patients survived to discharge without neurological deficits or other postE-CPR complications (36.3%). Seven patients died after E-CPR, and with one patient, there was no return of spontaneous beating during E-CPR (0.9%). Three patients died of unstable haemodynamics despite revascularisation of the coronary circulation. Three patients were successfully weaned off ECMO; however, they died subsequently of multiple organ dysfunction, unstable haemodynamic changes and septic shock from nosocomial infections, respectively. The outcome of E-CPR in adults with AMI was compared with previous studies at high-volume centres. Mortality or morbidity rates are not higher at a VLV centre.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca/terapia , Hospitais Gerais , Infarto do Miocárdio/terapia , Idoso , Reanimação Cardiopulmonar/efeitos adversos , Reanimação Cardiopulmonar/mortalidade , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/mortalidade , Feminino , Parada Cardíaca/etiologia , Parada Cardíaca/mortalidade , Mortalidade Hospitalar , Hospitais Gerais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida , Taiwan , Fatores de Tempo , Resultado do Tratamento
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