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1.
Nanotechnology ; 31(28): 282001, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32240995

RESUMO

Artificial photosynthesis is an effective way to convert solar energy into fuels, which is of great significance to energy production and reduction of atmospheric CO2 content. In recent years, 3D structured artificial photosynthetic system has made great progress as an effective design strategy. This review first highlights several typical mechanisms for improved artificial photosynthesis with 3D structures: improved light harvesting, mass transfer and charge separation. Then, we summarize typical examples of 3D structured artificial photosynthetic systems, including bioinspired structures, photonic crystals (PC), designed photonic structures (PC coupling structure, plasmon resonance structure, optical resonance structure, metamaterials), 3D-printed systems, nanowire integrated systems and hierarchical 3D structures. Finally, we discuss the problems and challenges to the application and development of 3D artificial photosynthetic system and the possible trends of future development. We hope this review can inspire more progress in the field of artificial photosynthesis.

2.
Sensors (Basel) ; 19(5)2019 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-30832402

RESUMO

Flexible strain sensors have a wide range of applications in biomedical science, aerospace industry, portable devices, precise manufacturing, etc. However, the manufacturing processes of most flexible strain sensors previously reported have usually required high manufacturing costs and harsh experimental conditions. Besides, research interests are often focused on improving a single attribute parameter while ignoring others. This work aims to propose a simple method of manufacturing flexible graphene-based strain sensors with high sensitivity and fast response. Firstly, oxygen plasma treats the substrate to improve the interfacial interaction between graphene and the substrate, thereby improving device performance. The graphene solution is then sprayed using a soft PET mask to define a pattern for making the sensitive layer. This flexible strain sensor exhibits high sensitivity (gauge factor ~100 at 1% strain), fast response (response time: 400⁻700 µs), good stability (1000 cycles), and low overshoot (<5%) as well. Those processes used are compatible with a variety of complexly curved substrates and is expected to broaden the application of flexible strain sensors.

3.
Sensors (Basel) ; 18(7)2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29954126

RESUMO

The scale factor drifts and other long-term instability drifts of Micro-Electro-Mechanical System (MEMS) inertial sensors are the main contributors of the position and orientation errors in high dynamic environments. In this paper, a novel high dynamic micro vibrator, which could provide high acceleration and high angular rate rotation with integrated optical displacement detector, is proposed. Commercial MEMS inertial sensors, including 3-axis accelerometer and 6-axis inertial measurement unit which is about 3 mm * 3 mm * 1 mm with 19 mg, could be bonded on the vibration platform of the micro vibrator to perform in-situ during the self-calibration procedure. The high dynamic micro vibrator is fabricated by a fully-integrated MEMS process, including lead zirconate titanate (PZT) film deposition, PZT and electrodes patterning, and structural ion etching. The optical displacement detector, using vertical-cavity surface-emitting laser (VCSEL) and photoelectric diodes (PD), is integrated on the top of the package to measure the 6-DOF vibrating displacement with the detecting resolution of 150 nm in the range of 500 μm. The maximum out-of-plane acceleration of the z-axis vibrating platform loaded with commercial 3-axis accelerometer (H3LIS331DL) achieves above 16 g and the maximum angular velocity achieves above 720°/s when the driving voltage is ±6 V.

4.
J Am Chem Soc ; 139(10): 3889-3895, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28233999

RESUMO

With growing concern over world environmental problems and increasing legislative restriction on using lead and lead-containing materials, a feasible replacement for lead-based piezoceramics is desperately needed. Herein, we report a large piezoelectric strain (d33*) of 470 pm/V and a high Curie temperature (Tc) of 243 °C in (Na0.5K0.5)NbO3-(Bi0.5Li0.5)TiO3-BaZrO3 lead-free ceramics by doping MnO2. Moreover, excellent temperature stability is also observed from room temperature to 170 °C (430 pm/V at 100 °C and 370 pm/V at 170 °C). Thermally stimulated depolarization currents (TSDC) analysis reveals the reduced defects and improved ferroelectricity in MnO2-doped piezoceramics from a macroscopic view. Local poling experiments and local switching spectroscopy piezoresponse force microscopy (SS-PFM) demonstrates the enhanced ferroelectricity and domain mobility from a microscopic view. Distinct grain growth and improvement in phase angle may also account for the enhancement of piezoelectric properties.

5.
J Inorg Biochem ; 250: 112421, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37922609

RESUMO

Six half-sandwich Ru(II) complexes (Ru1-Ru6), integrated with 5-phenyl-2-(pyridin-2-yl)-2,4-dihydro-3H-pyrazol-3-one (PDPO1-PDPO6) ligands, were synthesized and spectroscopically characterized. The structure of Ru3 that crystallized as a monoclinic crystal with P21/c space group was further confirmed by X-ray single crystal diffraction. Prototropic tautomerism within the complexes transformed OH-form ligands to NH-form, forming a hydrogen bond (Cl1---H-N3). The complexes and ligands' cytotoxicity was assessed against several cancerous (HepG2, A549, MCF-7) and normal Vero cell lines. Relative to the ligands and Cisplatin, complexes (Ru2, Ru3, Ru5, Ru6) exhibited potent cytotoxicity against cancer cells, with IC50 values from 2.05 to 15.69 µM/L, excluding Ru1 and Ru4. Specifically, Ru2, Ru3, and Ru5 demonstrated superior anti-HepG2 properties. Compared to Cisplatin, Ru2 and Ru5 were less toxic to Vero cells, highlighting their enhanced selectivity in toxicity. Structure-activity relationship (SAR) studies indicated that t-butyl substitution (in Ru2) or -Cl (in Ru5) on the benzene ring significantly improved the selective toxicity. These complexes manifested substantial lipophilicity, cellular uptake, and were quickly hydrolyzed to Ru-H2O species. Roughly positive correlations were observed between hydrolysis rate, lipophilicity, cellular uptake, and anticancer activities. Ru2, investigated specifically, induced apoptosis in HepG2 cells at concentrations of 10 and 20 µM/L through ROS-mediated mitochondrial dysfunction and G0/G1phase arrest, associated with altered P21, cyclin D, and CDK4 expression levels.


Assuntos
Antineoplásicos , Complexos de Coordenação , Rutênio , Animais , Chlorocebus aethiops , Cisplatino/farmacologia , Células Vero , Antineoplásicos/química , Apoptose , Mitocôndrias , Rutênio/química , Complexos de Coordenação/química , Linhagem Celular Tumoral
6.
Transl Lung Cancer Res ; 13(4): 861-874, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38736501

RESUMO

Background: The administration of immune checkpoint inhibitors (ICIs) in advanced non-small cell lung cancer (NSCLC) with oncogenic driver alterations other than epidermal growth factor receptor (EGFR) aroused a heated discussion. We thus aimed to evaluate ICI treatment in these patients in real-world routine clinical practice. Methods: A multicenter, retrospective study was conducted for NSCLC patients with at least one gene alteration (KRAS, HER2, BRAF, MET, RET, ALK, ROS1) receiving ICI monotherapy or combination treatment. The data regarding clinicopathologic characteristics, clinical efficacy, and safety were investigated. Results: A total of 216 patients were included, the median age was 60 years, 72.7% of patients were male, and 46.8% had a smoking history. The molecular alterations involved KRAS (n=95), HER2 (n=42), BRAF (n=22), MET (n=21), RET (n=14), ALK (n=14), and ROS1 (n=8); 56.5% of patients received immunotherapy in the first-line, and the rest 43.5% were treated as a second-line and above. For the entire cohort who received immunotherapy-based regimens in the first-line, the median progression-free survival (PFS) was 7.5 months and the median overall survival (OS) was 24.8 months. For the entire cohort who received immunotherapy-based regimens in the second-line and above, the median PFS was 4.7 months and median OS was 17.1 months. KRAS mutated NSCLC treated with immunotherapy-based regimens in the first-line setting had a median PFS and OS were 7.8 and 26.1 months, respectively. Moreover, the median PFS and OS of immunotherapy-based regimens for KRAS-mutant NSCLC that progressed after chemotherapy were 5.9 and 17.1 months. Programmed death ligand 1 (PD-L1) expression level was not consistently associated with response to immunotherapy across different gene alteration subsets. In the KRAS group, PD-L1 positivity [tumor proportion score (TPS) ≥1%] was associated with better PFS and OS according to the multivariate Cox analysis. No statistically significant association was found for smoking status, age, or gender with clinical efficacy in any gene group analyses. Conclusions: KRAS-mutant NSCLC could obtain clinical benefits from ICIs either for treatment-naive patients or those who have experienced progression after chemotherapy, and PD-L1 positive expression (TPS >1%) may be a potential positive predictor. For NSCLC with ALK, RET and ROS1 rearrangement, MET exon 14 skipping mutation, or BRAF V600E mutation, effectiveness of single or combined ICI therapy remains limited, therefore, targeted therapies should be considered prior to immunotherapy regimens. Future studies should address the investigation of better predictive biomarkers for immunotherapy response in oncogene-driven NSCLC.

7.
Front Oncol ; 12: 945620, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059688

RESUMO

BRAF gene has been identified as an oncogenic driver and a potential target in various malignancies. BRAF fusions are one subtype of BRAF alterations with a rare frequency. Here, we first report a previously treated advanced lung adenocarcinoma patient with de novo SND1-BRAF fusion who achieves partial response to the MAK inhibitor trametinib. We also provide a literature review on targeted therapies for BRAF fusions.

8.
J Diabetes Investig ; 12(8): 1490-1500, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33411988

RESUMO

AIMS/INTRODUCTION: Differentially expressed microribonucleic acids (miRNAs) in the placenta and circulating exosomes are of diagnostic value for gestational diabetes mellitus (GDM). In a cross-sectional study, we identified miRNAs expressed both in the placenta and circulating exosomes of pregnant women with GDM, and estimated their diagnostic value. MATERIALS AND METHODS: Next-generation sequencing was used to identify miRNAs in the placenta that were differentially expressed between GDM and normal glucose tolerance pregnancies. Quantitative polymerase chain reaction was used to validate the identified targets. Western blot and transmission electron microscopy were used to validate exosomes. Univariate logistic regression analysis was used to establish diagnostic models based on miRNAs expression, and the diagnostic value was estimated using the receiver operator characteristic curve. RESULTS: We identified 157 dysregulated miRNAs in the placental tissue obtained from GDM pregnancies. Of these, miRNA-125b was downregulated (P < 0.001), whereas miRNA-144 was upregulated (P < 0.001). The patterns of these two miRNAs remained the same in circulating exosomes from GDM pregnancies (all P < 0.001). miRNA-144 levels in the circulating exosomes negatively correlated with body mass index both before pregnancy (P = 0.018) and before delivery (P = 0.039), and positively correlated with blood glucose at 1 h, estimated using the oral glucose tolerance test (P = 0.044). The area under curve for the established diagnostic model was 0.898, which was higher than blood glucose levels at 0 h. CONCLUSIONS: These findings suggest that miRNA-125b and miRNA-144 are consistently dysregulated in circulating exosomes and the placenta from GDM pregnancies, and are of excellent diagnostic value for GDM.


Assuntos
Diabetes Gestacional/diagnóstico , Exossomos/química , MicroRNAs/análise , Placenta/química , Adulto , Área Sob a Curva , Glicemia/análise , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , MicroRNAs/genética , Valor Preditivo dos Testes , Gravidez , Curva ROC , Adulto Jovem
9.
Front Oncol ; 11: 680402, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660263

RESUMO

BACKGROUND: Microtubule-associated proteins (MAPs) have been considered to play significant roles in the tumor evolution of non-small cell lung cancer (NSCLC). Nevertheless, mRNA transcription levels and prognostic value of distinct MAPs in patients with NSCLC remain to be clarified. METHODS: In this study, the Oncomine database, Gene Expression Profiling Interactive Analysis (GEPIA) database, and Human Protein Atlas were utilized to analyze the relationship between mRNA/protein expression of different MAPs and clinical characteristics in NSCLC patients, including tumor type and pathological stage. The correlation between the transcription level of MAPs and overall survival (OS) of NSCLC patients was analyzed by Kaplan-Meier plotter. Besides, 50 frequently altered neighbor genes of the MAPs were screened out, and a network has been constructed via the cBioPortal and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) dataset. Meanwhile, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis on the expression data of MAPs and their 50 frequently altered neighbor genes in NSCLC tissues. Furthermore, The Cancer Immunome Atlas (TCIA) was utilized to analyze the relationship between MAP expression and the response to immunotherapy. Finally, we used reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to verify the expression of MAPs in 20 patients with NSCLC. RESULTS: The present study discovered that the mRNA transcription levels of MAP7/7D2 were enriched in NSCLC tissues, while those of the MAP2/4/6/7D3 were lower in NSCLC specimens than those in control specimens. The mRNA transcription level of MAP6 was significantly associated with the advanced stage of NSCLC. Besides, survival analysis indicated that higher mRNA expressions of MAP2/4/6/7/7D3 were correlated considerably with favorable OS of NSCLC patients, whereas increased mRNA expression levels of MAP1A/1S were associated with poor OS. Moreover, the expression of MAP1A/1B/1S/4/6/7D1/7D3 was significantly correlated with immunophenoscore (IPS) in NSCLC patients. CONCLUSIONS: Our analysis indicated that MAP1A/1S could serve as potential personalized therapeutic targets for patients with NSCLC, and the enriched MAP2/4/6/7/7D3 expression could serve as a biomarker for favorable prognosis in NSCLC. Besides, the expression of MAP1A/1B/1S/4/6/7D1/7D3 was closely related to the response to immunotherapy. Taken together, MAP expression has potential application value in the clinical treatment and prognosis assessment of NSCLC patients, and further verifiable experiments can be conducted to verify our results.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33090950

RESUMO

This work demonstrates the ultrasonic imaging ability of piezoelectric micromachined ultrasonic transducer (PMUT) for the detection of defects deep in solids by total-focus imaging algorithm. The 3-MHz PMUT array uses thin-film PZT as the material for energy transformation because of its high piezoelectric coefficient. Six columns with 12 PMUT units each exhibit an acoustic pressure of 137 kPa measured in water at 1 cm away when driven by a 27-Vpp input. Butter is chosen experimentally as the coupling agent to solids because of its low noise level and short cycling down. Through multilevel processing of echoes and total-focus algorithm, the 2-D image of a graphite plant was obtained with four holes identified based on our customized impedance-matched imaging system. The 16 columns of PMUT array with an area of 5.8 mm ×4.2 mm exhibit the imaging ability of an area of 40 mm ×40 mm in the graphite plant with identified defects deep as 3 cm. These results indicate that PMUT has the detection and imaging ability for defects deep in solids, not merely surface within hundreds of micrometers, and it has the potential for 3-D imaging, especially those occasions in limited space.

11.
IEEE Trans Ultrason Ferroelectr Freq Control ; 67(10): 2135-2141, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32746162

RESUMO

This article presents the piezoelectric micromachined ultrasonic transducer (PMUT) and its arrays that were based on a sputtered PZT/Si diaphragm structure and prototyped from an SOI substrate. Due to the high piezoelectric coefficient of PZT, polarization tuning pretreatment, and membrane thickness optimization, the PMUT shows high transmitting sensitivity in air and good coupling capability to liquid and solid. The PMUT transmitter exhibited a high sensitivity of 809, 190, and 135 nm/V at a resonant frequency of 0.450, 0.887, and 1.689 MHz, respectively, in air. The 5 ×5 array of 0.5-MHz PMUTs' acoustic output in water was measured as 42.4 Pa at a distance of 3 cm with a 10.0- [Formula: see text] input. Thickness-measuring ability in solids was evaluated with an 8 ×8 array of 1-MHz PMUTs as transmitter providing 8.0- [Formula: see text] input and another single PMUT of identical frequency response as receiver showing 0.2 [Formula: see text] (after 20 times magnification) output when the acoustic wave was transmitted through a 5-cm-thick graphite plate. Meanwhile, the time response of the receiver through different thicknesses of graphite plates is in reasonable agreement with predication from the analytical calculation. This high-performance PMUT with good coupling to solids will be utilized in various applications for solid-state sensing and detecting or as an alternative to the bulk piezoelectric ceramic transducers in the near future.

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