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1.
Opt Express ; 30(10): 15929-15938, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221447

RESUMO

Augmented reality (AR) three-dimensional (3D) display is the hardware entrance of metaverse and attracts great interest. The fusion of physical world with 3D virtual images is non-trivial. In this paper, we proposed an AR 3D display based on a pixelated volume holographic optical element (P-VHOE). The see-through combiner is prepared by spatial multiplexing. A prototype of AR 3D display with high diffraction efficiency (78.59%), high transmission (>80%) and non-repeating views is realized. Virtual 3D objects with high fidelity in depth is reconstructed by P-VHOE, with a complex wavelet structural similarity (CW-SSIM) value of 0.9882. The proposed prototype provides an efficient solution for a compact glasses-free AR 3D display. Potential applications include window display, exhibition, education, teleconference.

2.
Xenotransplantation ; 24(6)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28833558

RESUMO

Xenotransplantation is an effective way to solve the problem of donor shortage in clinical transplantation. However, clinical use of xenotransplantation is currently limited due to immunological challenges such as acute vascular rejection and cell-mediated rejection. To finally surpass this immunological barrier, more preclinical research is needed into the molecular mechanisms of rejection and the possible effects of new immunosuppressants. Our aim was to create a refined, highly reproducible protocol to establish the most suitable rat-to-mouse heterotopic heart transplantation model using the cuff technique.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/imunologia , Transplante de Coração , Animais , Modelos Animais de Doenças , Rejeição de Enxerto/imunologia , Transplante de Coração/métodos , Xenoenxertos , Imunossupressores/farmacologia , Camundongos , Ratos , Transplante Heterólogo/métodos , Transplante Heterotópico/métodos
3.
Micromachines (Basel) ; 15(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38675254

RESUMO

As the next generation of in-vehicle intelligent platforms, the augmented reality heads-up display (AR-HUD) has a huge information interaction capacity, can provide drivers with auxiliary driving information, avoid the distractions caused by the lower head during the driving process, and greatly improve driving safety. However, AR-HUD systems still face great challenges in the realization of multi-plane full-color display, and they cannot truly achieve the integration of virtual information and real road conditions. To overcome these problems, many new devices and materials have been applied to AR-HUDs, and many novel systems have been developed. This study first reviews some key metrics of HUDs, investigates the structures of various picture generation units (PGUs), and finally focuses on the development status of AR-HUDs, analyzes the advantages and disadvantages of existing technologies, and points out the future research directions for AR-HUDs.

4.
Micromachines (Basel) ; 14(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37512712

RESUMO

We propose a method for designing a long-focal-depth diffractive achromat (LFDA). By applying rotational symmetric parameterization, an LFDA with a diameter of 10.89 mm is designed over three wavelengths at six focal planes. The smoothly changed slope designed by the binary variable slope search (BVSS) algorithm greatly reduces the discontinuity in depth, thus it is a fabrication-friendly process for grayscale laser direct writing lithography, involving less fabrication error and cost. The deviation between the designed and fabricated profiles amounts to 9.68%. The LFDA operates at multiple wavelengths (654 nm, 545 nm, and 467 nm) with a DOF of 500 mm~7.65λ × 105 (λ = 654 nm). The simulated and measured full-width at half-maximum (FWHM) of the focused beam is close to the diffraction limit. Experimental studies suggest that the LFDA possesses a superior capability to form high-quality chromatic images in a wide range of depths of field. The LFDA opens a new avenue to achieve compact achromatic systems for imaging, sensing, and 3D display.

5.
Life Sci ; 325: 121686, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37030616

RESUMO

AIMS: Mitochondrial dysfunction is a critical pathological change in cerebral ischemia. Mitochondrial pyruvate carrier 1 (MPC1) is a mitochondrial inner membrane protein carrier participating in pyruvate transport. The work is aiming to figure out the effect of MPC1 on cerebral ischemia. MAIN METHODS: Bilateral internal carotid artery embolization (BICAO) model and oxygen glucose deprivation/reoxygenation (OGD/R) model were used to simulate cerebral ischemia in vivo and in vitro. The effect of MPC1 on cerebral ischemia was detected by imaging, behavioral test, immunofluorescence, flow cytometry, transmission electron microscopy, Western blot and RT-Q-PCR. RNA-sequence (RNA-seq) was applied to explore the potential molecular mechanisms underlying the role of MPC1 in cerebral ischemia. KEY FINDING: After BICAO or OGD/R treatment, MPC1 expression in ischemic cortical neurons was significantly decreased. And MPC1 deficiency significantly reduced cerebral blood flow, decreased locomotion activities and exacerbated neuronal injury. Moreover, MPC1 deficiency obviously aggravated oxidative stress, structural disruption and dysfunction of mitochondria, autophagy and calcium overload of ischemic cortical neurons. Interestingly, MPC1 overexpression remarkably reversed neuronal loss and persisting neuronal deficits induced by OGD. Using RNA-seq, 38 MPC1-associated differentially expressed genes were involved in oxidative stress, autophagy and calcium overload. Our results further confirmed that MPC1 could alleviate autophagy via the PI3K/Akt/mTOR pathway in the ischemic cortical neurons. SIGNIFICANCE: MPC1 may exert neuroprotective effects by attenuating oxidative stress, mitochondrial dysfunction, calcium overload and autophagy during cerebral ischemia. MPC1-related genes identified by RNA-seq may be a novel therapeutic target for cerebral ischemia.


Assuntos
Lesões Encefálicas , Hipóxia-Isquemia Encefálica , Animais , Ratos , Apoptose , Autofagia , Isquemia Encefálica/patologia , Cálcio/metabolismo , Infarto Cerebral , Glucose/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Fosfatidilinositol 3-Quinases/metabolismo , Traumatismo por Reperfusão/patologia
6.
Talanta ; 261: 124677, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37201340

RESUMO

Since there is no effective Alzheimer's disease (AD)-modifying therapy available currently, early analysis of AD core biomarkers has become one of great significance and common concern in clinical diagnosis. Herein, we designed an Au-plasmonic shell attached polystyrene (PS) microsphere in a microfluidic chip for simultaneous detection of Aß1-42 and p-Tau181 protein. The corresponding Raman reporters were identified in femto gram level by ultrasensitive surface enhanced Raman spectroscopy (SERS). Both of Raman experimental data and finite-difference time-domain modeling demonstrates the synergetic coupling between PS microcavity with the optical confinement property and the localized surface plasmon resonance (LSPR) of AuNPs, so leading to highly amplified electromagnetic fields at the 'hot spot'. Moreover, the microfluidic system is designed with multiplex testing and control channels in which the AD-related dual proteins were detected quantitatively with a lower limit of 100 fg mL-1. Thus, the proposed microcavity-based SERS strategy initiates a new way for accurately prediction of AD in human blood samples and provides the potential application for synchronous determination of multiple analytes in general disease assays.


Assuntos
Doença de Alzheimer , Nanopartículas Metálicas , Humanos , Doença de Alzheimer/diagnóstico , Ouro/química , Microfluídica , Nanopartículas Metálicas/química , Biomarcadores/análise , Análise Espectral Raman/métodos , Diagnóstico Precoce
7.
ACS Appl Mater Interfaces ; 14(14): 16949-16957, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35363461

RESUMO

Dynamic diffraction gratings (DDGs) are considered as one of the most promising technologies for application in smart optical devices because of their in situ dynamic regulation of light propagation on demand; however, it is still a challenge to fabricate dynamic periodic micro/nanostructures due to limited materials and processes. Here, a facile and feasible strategy to construct a near-infrared (NIR) radiation-driven DDG is developed based on a double-sided surface pattern, which is fabricated by dynamic wrinkles and/or soft-imprinted static wrinkles. Poly(dimethylsiloxane) (PDMS) containing carbon nanotubes (CNTs) serves as the substrate, and wrinkles are formed on both sides. The resulting double-sided wrinkle pattern can be used as a DDG to generate various adjustable two-dimensional (2D) diffraction patterns driven by NIR light. Furthermore, with various combinations of wrinkles, we demonstrated a single-sided responsive DDG and a double-sided responsive DDG to realize the evolution of diffraction patterns from 2D to one-dimensional (1D) and 2D to zero-dimensional (0D), respectively. The results provide an alternative for DDGs that will have wide applications in smart display, sensing, and imaging systems.

8.
Int J Oncol ; 59(1)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34036374

RESUMO

Tumour necrosis factor (TNF)­α­inducible protein 8 (TNFAIP8) is the founding member of the TIPE family. According to accumulating evidence, TNFAIP8 plays a pivotal role in the regulation of a variety of tumours, as well as inflammatory diseases. TNFAIP8 is suggested to act as an anti­apoptotic protein, affecting proliferation, metastasis, invasion, angiogenesis, drug resistance and immune response through multiple signalling pathways. From the clinical point of view, further studies should be required to confirm the prognostic value of TNFAIP8 and also clarify its possible contribution to the development of a novel therapeutic strategy to treat patients with tumours, including those of the breast, colon and lung, and inflammatory diseases. The present review focuses on the TIPE family member TNFAIP8 and describes the molecular mechanisms with regard to how TNFAIP8 could participate in the development of tumours as well as other conditions.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias/metabolismo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Neoplásica , Prognóstico , Transdução de Sinais
9.
Light Sci Appl ; 10(1): 213, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642293

RESUMO

Glasses-free three-dimensional (3D) displays are one of the game-changing technologies that will redefine the display industry in portable electronic devices. However, because of the limited resolution in state-of-the-art display panels, current 3D displays suffer from a critical trade-off among the spatial resolution, angular resolution, and viewing angle. Inspired by the so-called spatially variant resolution imaging found in vertebrate eyes, we propose 3D display with spatially variant information density. Stereoscopic experiences with smooth motion parallax are maintained at the central view, while the viewing angle is enlarged at the periphery view. It is enabled by a large-scale 2D-metagrating complex to manipulate dot/linear/rectangular hybrid shaped views. Furthermore, a video rate full-color 3D display with an unprecedented 160° horizontal viewing angle is demonstrated. With thin and light form factors, the proposed 3D system can be integrated with off-the-shelf purchased flat panels, making it promising for applications in portable electronics.

10.
Cell Transplant ; 30: 9636897211054503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34814739

RESUMO

Xenotransplantation is a potential solution for the severe shortage of human donor organs and tissues. The generation of humanized animal models attenuates strong innate immune responses, such as complement-mediated hyperacute rejection. However, acute vascular rejection and cell mediated rejection remain primary barriers to xenotransplantation, which limits its clinical application. In this study, we systematically investigated the immunosuppressive effect of LEF using a rat-to-mouse heart xenotransplantation model. SD rat xenogeneic hearts were transplanted into C57BL/6 mice, and survived 34.5 days after LEF treatment. In contrast, BALB/c allogeneic hearts were transplanted into C57BL/6 mice, and survived 31 days after LEF treatment. Compared to normal saline treatment, LEF treatment decreased xenoreactive T cells and CD19+ B cells in recipient splenocytes. Most importantly, LEF treatment protected myocardial cells by decreasing xenoreactive T and B cell infiltration, inflammatory gene expression, and IgM deposition in grafts. In vivo assays revealed that LEF treatment eliminated xenoreactive and alloreactive T and B lymphocytes by suppressing the activation of the NF-κB signaling pathway. Taken together, these observations complement the evidence supporting the potential use of LEF in xenotransplantation.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Imunossupressores/uso terapêutico , Leflunomida/uso terapêutico , NF-kappa B/efeitos dos fármacos , Transplante Heterólogo/métodos , Animais , Rejeição de Enxerto/patologia , Humanos , Tolerância Imunológica , Imunossupressores/farmacologia , Leflunomida/farmacologia , Masculino , Camundongos , Ratos , Transdução de Sinais
11.
Cell Death Discov ; 7(1): 272, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34601499

RESUMO

Colorectal cancer (CRC) is a common tumor that harms human health with a high recurrence rate. It has been reported that the expression of microRNA-539 (miR-539) is low in several types of cancer, including CRC. Tumor necrosis factor (TNF)-α-induced protein 8 (TNFAIP8/TIPE) is highly expressed in CRC and promotes the proliferation, migration and angiogenesis of CRC. However, the relationship between miR-539 and TIPE and the mechanisms by which they regulate the proliferation of CRC remain to be explored. We aimed to investigate the functions and mechanisms of miR-539 in CRC proliferation. Functionally, miR-539 can bind to and regulate the expression of TIPE, and miR-539 activates SAPK/JNK to downregulate the expression of glutathione peroxidase 4 (GPX4) and promote ferroptosis. Our data reveal the novel role of miR-539 in regulating ferroptosis in CRC via activation of the SAPK/JNK axis, providing new insight into the mechanism of abnormal proliferation in CRC and a novel potential therapeutic target for advanced CRC.

12.
Int J Biol Sci ; 16(2): 272-283, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929755

RESUMO

Background: Metastasis is the leading cause of death in colorectal cancer (CRC) patients. It is regulated mainly by tumor cell angiogenesis, and angiogenesis is caused by the binding of vascular endothelial growth factor (VEGF) to vascular endothelial growth factor receptor 2 (VEGFR2). Tumor necrosis factor-α-induced protein 8 (TNFAIP8, hereto after TIPE) plays an important role in tumorigenesis, development, and prognosis. However, the relationship between TIPE and VEGFR2 in CRC angiogenesis and the mechanism of action remain unknown. Method: In this study, we used quantitative real-time PCR, Western blotting and immunohistochemistry to detect TIPE and VEGFR2 expression in 55 specimens from CRC patients. We also used HCT116 CRC cells and human umbilical vein endothelial cells (HUVECs) for in vitro experiments by stably transducing shTIPE and shRNA control lentivirus into HCT116 cells, detecting VEGFR2 expression after TIPE knockdown and repurposing the culture supernatant as conditioned medium to stimulate angiogenesis of HUVECs. In vivo experiments with chicken chorioallantoic membranes (CAMs) and a nude mouse matrix subcutaneous tumor model were performed to validate the effects of TIPE on angiogenesis. Additionally, we analyzed the expression and phosphorylation levels of PDK1 and blocked PDK1 expression using inhibitors to determine whether TIPE-induced changes in VEGFR2-mediated angiogenesis acted via the PI3K-Akt pathway. Results: We found that TIPE and VEGFR2 are highly expressed in CRC and act as oncogenes. TIPE knockdown also downregulated VEGFR2 expression, which resulted in simultaneous inhibition of cell proliferation, cell migration and angiogenesis. Then, in vivo experiments further demonstrated that TIPE promotes angiogenesis in CRC. Finally, we found that TIPE promotes VEGFR2-mediated angiogenesis by upregulating PDK1 expression and phosphorylation and that blocking PDK1 expression can inhibit this process. Conclusion: TIPE promotes angiogenesis in CRC by regulating the expression of VEGFR2, which may be a target for antiangiogenic cancer therapy.


Assuntos
Neoplasias Colorretais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neovascularização Patológica/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
13.
Dalton Trans ; 45(42): 16889-16895, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27711785

RESUMO

A mechanism for the enhanced room-temperature phosphorescence (RTP) of gadolinium-coordinated hematoporphyrin monomethyl ether (Gd-HMME) in the presence of imidazole and free gadolinium ions (Gd3+) is revealed. Imidazole, the molten solvent used in the synthesis of Gd-HMME, was effective in enhancing the Gd-HMME RTP. In the presence of imidazole, further enhancement of the Gd-HMME RTP was observed upon adding Gd3+. Overall, a 40-fold enhancement of Gd-HMME RTP intensity was achieved by adding both imidazole and Gd3+. In addition, there was an increase in the RTP lifetime. Through spectroscopic analysis, we deduced that a protective medium is formed by the imidazole and the degree of this protection is further increased by Gd3+. The protective medium enhances the Gd-HMME RTP by partially inhibiting energy transfer from the lowest triplet state of Gd-HMME to oxygen. This was demonstrated by the presence of lower levels of singlet oxygen in the Gd-HMME solution after the addition of imidazole. These results indicate that imidazole could have potential application as an RTP enhancer or triplet state protector.

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