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1.
Adv Mater ; : e2400279, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548708

RESUMO

Light detection and ranging (LiDAR) is indispensable in applications such as unmanned aerial vehicles, autonomous driving, and biomimetic robots. However, the precision and available distance of LiDAR are constrained by the speed and sensitivity of the photodetector, necessitating the use of expensive and energy-consuming avalanche diodes. To address these challenges, in this study, a pyroelectricity-based acceleration strategy with 2D-(graded 3D) perovskite heterojunction is proposed to achieve a record high speed (27.7 ns with an active area of 9 mm2, and 176 ps with an active area of 0.2 mm2) and high responsivity (0.65 A W-1) at zero bias. This success is attributed to the unique mechanism where the electrons from the pyroelectric effect at the Cl-rich 2D/3D interface directly recombine with excess holes during light-dark transitions, breaking speed limitations related to carrier mobility and capacitive effect. Furthermore, the introduced pyroelectric effect significantly enhances the photoresponse, resulting in a self-powered external quantum efficiency exceeding 100%. The study also demonstrates precise position detection at the centimeter level. In conclusion, this research presents a pioneering approach for developing high-speed photodiodes with exceptional sensitivity, mitigating energy and cost concerns in LiDAR applications.

2.
Adv Mater ; : e2402253, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553842

RESUMO

Emerging neural morphological vision sensors inspired by biological systems that integrate image perception, memory, and information computing are expected to transform the landscape of machine vision and artificial intelligence. However, stable and reconfigurable light-induced synaptic behavior always relies on independent gateport modulation. Despite its potential, the limitations of uncontrollable defects and ionic characteristics have led to simpler, smaller, and more integration-friendly two-terminal devices being used as sidelines. In this work, the synergy between ion migration barriers and readout voltage is proven to be the key to realizing stable, reconfigurable, and precisely controllable postsynaptic current in two-terminal devices. Following the same mechanism, optical and electrical signal synchronous triggering is proposed to serve as a preprocessing method to achieve a recognition accuracy of 96.5%. Impressively, the gradual ion accumulation during the training process induces photocurrent evolution, serving as a reference for the dynamic learning rate and boosting accuracy to 97.8% in just 10 epochs. The PSC modulation potential under short optical pulse of 20 ns is also revealed. This optoelectronic device with perception, memory, and computation capabilities can promote the development of new devices for future photonic neural morphological circuits and artificial vision.

3.
Nat Commun ; 15(1): 2066, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453948

RESUMO

Free-space coupling, essential for various communication applications, often faces significant signal loss and interference from ambient light. Traditional methods rely on integrating complex optical and electronic systems, leading to bulkier and costlier communication equipment. Here, we show an asymmetric 2D-3D-2D perovskite structure device to achieve a frequency-selective photoresponse in a single device. By combining two electromotive forces of equal magnitude in the opposite directions, the device output is attenuated to zero under constant light illumination. Because these reverse photodiodes have different response speeds, the device only responds near a certain frequency, which can be tuned by manipulating the 2D perovskite components. The target device achieves an ultrafast response of 19.7/18.3 ns in the frequency-selective photoresponse range 0.8-9.7 MHz. This anti-interference photodetector can accurately transmit character and video data under strong light interference with a source intensity of up to 454 mW cm-2.

4.
Small Methods ; 7(11): e2300479, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37653642

RESUMO

The extensive applications of spectrum analysis across various fields have rendered the traditional desktop spectrometers unable to meet the market demand for portability and instantaneity. Reducing the size of spectrometers has become a topic of interest. Based on this trend, a novel type of computational spectrometer is developed and has been widely studied owing to its unique features. Such spectrometers do not need to integrate complex mechanical or optical structures, and most of them can achieve spectrum analysis by the properties of the material itself combines with the reconstruction algorithm. Impressively, a single-detector computational spectrometer has recently been successfully realized based on in situ modulation of material properties. This not only enables the further miniaturization of the device, but also means that the footprint-resolution limitation which has always existed in the field of hyperspectral imaging has been broken, opening a new era of image analysis. This review summarizes the classifications and principles of various spectrometers, compares the spectrum resolution performances of different types of spectrometers, and highlights the progress of computational spectrometers, especially the revolutionary single-detector spectrometer. It is expected that this review will provide a positive impact on expanding the boundary of spectrum analysis and move hyperspectral imaging forward.

5.
J Oncol ; 2022: 1403454, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420358

RESUMO

Background: Hepatocellular carcinoma (HCC) is a kind of primary liver cancer that accounts for more than 90% of primary hepatocellular carcinomas. Hyperuricemia is closely related to the development, recurrence, metastasis, and prognosis of cancer. Previous studies have proved that the serum uric acid level can increase the incidence rate and mortality of malignant tumors. However, the specific pathogenesis remains unstudied. Methods: RT-qPCR analysis showed that the mRNA expression of PDZK1 and ABCG2 increased significantly after HCC cells were exposed to different concentrations of soluble uric acid (2.5, 5, 10, 20 mg/dl) for 24 hours. Then, in HCC shRNAs, PDZK1, or over expression PDZK1 were used. CCK8, wound healing, and Transwell assay showed that PDZK1 regulates cell proliferation, invasion, and migration. Flow cytometry results revealed that PDZK1 affects cell apoptosis. Western blot results show that PDZK1 affects the STAT3/C-myc pathway. Then, in vivo tumorigenesis, allopurinol maybe an effective drug to advance: the prognosis of HCC. Results: In our study, RT-qPCR analysis showed that the mRNA expression of PDZK1 and ABCG2 increased significantly after different concentrations of soluble uric acid in HCC. Then, PDZK1 affects the proliferation, migration, and apoptosis of HCC through the STAT3/C-myc pathway. Conclusions: Hyperuricemia response affects the expression of PDZK1; PDZK1 affects the proliferation, migration, and apoptosis through the STAT3/C-myc pathway in hepatocellular carcinoma. It is suggested that PDZK1 maybe closely related to the occurrence, development, and prognosis of HCC and allopurinol maybe have potential anticancer effects.

6.
Contrast Media Mol Imaging ; 2022: 2413922, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992550

RESUMO

To address the problem of microstructural analysis of titania nanoparticles with high cytotoxicity, the authors propose X-ray phase-comparative CT imaging studies. In this method, the HE-stained section samples were compared with the X-ray phase-contrast CT imaging microscopic images, and 3D texture analysis was used to observe the changes in the preparation of hepatocyte microstructures in the two groups. The results show that X-ray phase-contrast CT imaging microscopic images and their larger image size are closely related to HE staining images, and X-ray phase-contrast CT microscopic images can observe important data of hepatocytes from multiple angles. The ship skeleton extraction method based on the endpoint limit also has advantages over traditional algorithms in extraction accuracy and can provide more 3D feature files, confirming the growth and transformation of normal hepatocytes into hepatocyte cytotoxic microstructures. The distribution effect of using the ensemble process is better than the simple 2D feature set and 3D feature set, and the overall accuracy is improved; the result distribution of the tree determination and random forest methods is also better than that of the support vector machine method. The experimental results show that the X-ray phase-contrast CT images can highlight the 2D and 3D imaging features of the hepatotoxic microstructure of TiO2 nanoparticles and provide data for quantitative analysis.


Assuntos
Nanopartículas , Tomografia Computadorizada por Raios X , Algoritmos , Imageamento Tridimensional/métodos , Titânio , Tomografia Computadorizada por Raios X/métodos , Raios X
7.
Contrast Media Mol Imaging ; 2022: 6483087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35854771

RESUMO

To address the question of determining the osteogenic differentiation of mesenchymal stem cells, the bone marrow studies were performed using probe microscopy. All adherent bone marrow was used to isolate the bone marrow mesenchymal stem cells and expanded and purified in vitro. Its morphology under an inverted microscope was observed. We used Zuogui Pills to differentiate the separation methods. Alcian blue staining, modified calcium cobalt alkaline phosphatase staining, and neuron-specific enolase immunohistochemical staining were performed. The experimental results are shown below. The morphology of the isolated and purified cells was analyzed with an inverted microscope, and the isolated and purified cells were analyzed with Zuogui Pill. Alcian blue staining, modified calcium cobalt alkaline phosphatase staining, and neuron-specific enolase immunohistochemical staining confirmed that the cells differentiated into cartilage and osteoblasts, and the cell structure and morphology were similar to those of the bone marrow mesenchymal stem cells. The results showed that the adherent mode of cells obtained from the whole bone marrow was the rat bone marrow mesenchymal stem cells, and the Zuogui Pills could induce multidirectional differences in the bone marrow mesenchymal stem cells.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Azul Alciano , Fosfatase Alcalina , Animais , Medula Óssea , Células da Medula Óssea , Cálcio , Células Cultivadas , Cobalto , Microscopia de Varredura por Sonda , Fosfopiruvato Hidratase , Ratos
8.
Adv Mater ; 34(33): e2200221, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35706366

RESUMO

There are significant applications for miniature on-chip spectrometers in many fields. However, at present, on-chip spectrometers have to utilize an integrated strategy to achieve spectral analysis, which undoubtedly squanders the photosensitive area and adds pressure to the miniaturization of the spectrometer. Here, a unique spectrometer design that adopts a single detection point with in situ modulation realized by the photogain control at various bias voltages is demonstrated. With micrometer-level footprints, this single-dot spectrometer processes a resolution of about 5 nm and a response time down to about 197 µs. This is the first in situ perovskite modulation strategy that breaks the footprint-resolution restriction of spectrum analysis and demonstrates a new design direction for functional perovskite devices.

9.
Adv Mater ; 33(51): e2105761, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34655116

RESUMO

The working principle of the triboelectric nanogenerator (TENG), contact electrification and electrostatic induction, has been used to harvest raindrop energy in recent years. However, the existing research is mainly concentrated on solid-liquid electrification, and adopts traditional electrostatic induction (TEI) for output. As a result, the efficiency of droplet electricity generators (DEGs) is severely constrained. Therefore, previous studies deem that the DEG output is limited by interfacial effects. This study reveals that this view is inappropriate and, in reality, the output strategy is the key bottleneck restricting the DEG performance. Here, a switch effect based on an electric-double-layer capacitor (EDLC) is introduced, and an equivalent circuit model is established to understand its working mechanism. Without pre-charging, a single droplet can generate high voltage over 100 V and the output is directly improved by two-orders of magnitude compared with TEI, which is precisely utilizing the interfacial effect. This work provides insightful perspective and lays solid foundation for DEG applications in large scale.

10.
J Control Release ; 338: 571-582, 2021 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-34481026

RESUMO

Bone is a dynamic self-healing organ and a continuous remodeling ensures the restoration of the bone structure and function over time. However, bone remodeling is not able to repair large traumatic injuries. Therefore, surgical interventions and bone substitutes are required. The aim of bone tissue engineering is to repair and regenerate tissues and engineered a bone graft as a bone substitute. To met this goal, several natural or synthetic polymers have been used to develop a biocompatible and biodegradable polymeric construct. Among the polymers, natural polymers have higher biocompatibility, excellent biodegradability, and no toxicity. So far, collagen, chitosan, gelatin, silk fibroin, alginate, cellulose, and starch, alone or in combination, have been widely used in bone tissue engineering. These polymers have been used as scaffolds, hydrogels, and micro-nanospheres. The functionalization of the polymer with growth factors and bioactive glasses increases the potential use of polymers for bone regeneration. As bone is a dynamic highly vascularized tissue, the vascularization of the polymeric scaffolds is vital for successful bone regeneration. Several in vivo and in vitro strategies have been used to vascularize the polymeric scaffolds. In this review, the application of the most commonly used natural polymers is discussed.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Materiais Biocompatíveis , Regeneração Óssea , Osso e Ossos , Polímeros
11.
Medicine (Baltimore) ; 98(24): e15945, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31192931

RESUMO

BACKGROUND: Fluoxetine has been reported to treat anorexia nervosa (AN) caused by chemotherapy in patients with cholangiocarcinoma effectively. However, no study systematically investigated its efficacy and safety. Thus, this study will systematically assess its efficacy and safety for AN caused by chemotherapy in patients with cholangiocarcinoma. METHODS: A comprehensive literature search for relevant studies will be conducted from the following databases from inception to the present: MEDILINE, EMBASE, Cochrane Library, Web of Science, PSYCINFO, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All randomized controlled trials on assessing the efficacy and safety of fluoxetine for AN caused by chemotherapy in patients with cholangiocarcinoma will be considered for inclusion in this study. RevMan V.5.3 software will be used for risk of bias assessment and statistical analysis. RESULTS: This study will summarize the latest evidence of fluoxetine for AN caused by chemotherapy in patients with cholangiocarcinoma through assessing outcomes of weight, depression, anxiety, and quality of life. Additionally, any adverse events will also be analyzed. CONCLUSION: The findings of this study will provide most recent evidence of fluoxetine for AN caused by chemotherapy in patients with cholangiocarcinoma. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019131583.


Assuntos
Anorexia Nervosa/tratamento farmacológico , Antidepressivos de Segunda Geração/uso terapêutico , Antineoplásicos/efeitos adversos , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Fluoxetina/uso terapêutico , Anorexia Nervosa/induzido quimicamente , Neoplasias dos Ductos Biliares/psicologia , China , Colangiocarcinoma/psicologia , Feminino , Humanos , Masculino , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Resultado do Tratamento
12.
Int Immunopharmacol ; 62: 114-119, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30005226

RESUMO

Thyroid cancer is one of the malignancies with better clinical outcomes. However, a minority of patients develops an aggressive anaplastic thyroid carcinoma. Development of innovative and multimodal therapeutic strategies is urgently needed. Here, we investigated the role of CXCR5+ CD8 T cells in the peripheral blood, tumor-involved lymph nodes (TILN), and tumor mass of thyroid cancer patients. In peripheral blood mononuclear cells, CXCR5+ cells represented 1.4% ±â€¯0.84% (mean ±â€¯s.d.) of total CD8 T cells, while in TILN and in tumor, the frequencies of CXCR5+ CD8 T cells were significantly higher at 27.7% ±â€¯7.8% and 15.5% ±â€¯2.9%, respectively. Compared to CXCR5- CD8 T cells, CXCR5+ CD8 T cells presented significantly higher PD-1 expression and lower or comparable TIM-3 and CTLA-4 expression. To compare and contrast the functional characteristics of CXCR5+ CD8 T cells and CXCR5- CD8 T cells, these cells were separated from TILNs and were TCR-stimulated via anti-CD3/CD28. Upon stimulation, CXCR5+ CD8 T cells presented stronger downregulation of CD27, higher expression of proinflammatory cytokines IL-2, IFN-γ, and TNF-α, and higher proliferation capacity than CXCR5- CD8 T cells. Moreover, CXCR5+ CD8 T cells presented higher expression of cytotoxic molecules Gzm-A, Gzm-B, and perforin. Overall, these results demonstrated that in thyroid cancer patients CXCR5+ CD8 T cells infiltrated the TILNs and the tumors, and were functionally more potent compared to their CXCR5- counterpart.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfonodos/imunologia , Ativação Linfocitária , Receptor de Morte Celular Programada 1/genética , Receptores CXCR5/imunologia , Câncer Papilífero da Tireoide/imunologia , Adulto , Antígeno CTLA-4/metabolismo , Células Cultivadas , Feminino , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Linfonodos/irrigação sanguínea , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Receptores CXCR5/metabolismo , Câncer Papilífero da Tireoide/sangue , Câncer Papilífero da Tireoide/patologia , Transcrição Gênica/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética
13.
Biomed Pharmacother ; 103: 167-173, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29653361

RESUMO

Over the past decades, lncRNAs have attracted more and more attentions of researchers. It has been verified that lncRNAs can modulate multiple biological behaviors in various human cancers. LncRNA ASAP1-IT1 has been certified to be a tumor facilitator in several malignant tumors. This study aims to investigate the effects of dysregulated ASAP1-IT1 on biological processes of Cholangiocarcinoma. The high expression level of ASAP1-IT1 was tested in Cholangiocarcinoma tissues and cells with qRT-PCR. Upregulation of ASAP1-IT predicted the unfavorable prognosis for Cholangiocarcinoma patients. Next, ASAP1-IT1 was knocked down in cancerous cells for loss-of function assay. MTT, colony formation and transwell and western bot assays were performed to demonstrate the specific impacts of ASAP1-IT1 on proliferation, migration and EMT progression of Cholangiocarcinoma. Cells. As a results, the Cholangiocarcinoma progression was inhibited. Hedgehog signaling pathway has been discovered to be a treatment target in Cholangiocarcinoma. In this study, the interaction between ASAP1-IT1 and hedgehog pathway was specifically investigated. Smo and Gli1, two hedgehog-related proteins were examined in Cholangiocarcinoma cells. The results of qRT-PCR and western blot assay suggested that ASAP1-IT1 could positively modulate Smo and Gli1 in Cholangiocarcinoma. Finally, rescue assays were carried out to prove that ASAP1-IT1 could improve Cholangiocarcinoma progression and development via hedgehog signaling pathway.


Assuntos
Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Proteínas Hedgehog/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , RNA Longo não Codificante/genética
14.
Oncol Rep ; 31(4): 1891-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24535079

RESUMO

Hypoxia is a microenvironmental factor which plays a critical role in tumor development and chemoresistance. Epithelial-to-mesenchymal transition (EMT) induced by hypoxia is one of the critical causes of treatment failure and chemoresistance in different types of human cancers. Stabilization of the hypoxia-inducible factor-1α (HIF-1α) transcription complex, caused by intratumoral hypoxia, promotes tumor progression and chemoresistance. Previous evidence suggests that hypoxia can also activate nuclear factor-κB (NF-κB), a known mediator of EMT, which is accompanied by reduced expression of epithelial marker E-cadherin and enhanced expression of the mesenchymal markers Vimentin and N-cadherin as well as overexpression of various transcription factors of EMT, such as Snail and Twist. Based on this evidence, the present study aimed to investigate whether downregulation of the p65 subunit of NF-κB or HIF-1α by small interfering RNA (siRNA) may reverse the EMT phenotype and inhibit the proliferation and induce the apoptosis of pancreatic cancer cell lines (PANC-1, BxPC3) under hypoxic conditions in vitro and enhance the efficacy of gemcitabine in the treatment of pancreatic cancer. These results provide molecular evidence showing that the activation of the HIF-1α and NF-κB loop is mechanistically linked with the chemoresistance phenotype (EMT phenotype) of pancreatic cancer cells under hypoxic conditions, suggesting that the inactivation of HIF-1α and NF-κB signaling by novel strategies may be a potential targeted therapeutic approach for overcoming EMT and chemoresistance induced by hypoxia.


Assuntos
Hipóxia Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , NF-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Acetilcisteína , Apoptose , Western Blotting , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Neoplasias Pancreáticas/patologia , Fenótipo , Transdução de Sinais/fisiologia , Transfecção
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