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1.
Nano Lett ; 24(35): 11036-11042, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39185718

RESUMO

The phase-shifting structured light illumination technique is widely used in imaging but often relies on mechanical translation stages or spatial light modulators, leading to system instability, low displacement accuracy, and limited integration feasibility. In response to these challenges, we propose and demonstrate an approach for generating far-field phase-shifting structured light using a polarization multiplexing metasurface. By controlling the polarization states of incident and transmitted light, the metasurface creates a three-step displacement of structured light, eliminating the need to move samples or illumination sources. As a proof of concept, we experimentally demonstrate microscopic imaging using structured light illumination generated by metasurfaces, extracting high-frequency information from objects, and surpassing the diffraction limit. The proposed metasurface platform offers a promising approach for developing compact and robust phase-shifting imaging systems, with broad prospects in quantitative detection, machine vision, and beyond.

2.
Nat Commun ; 15(1): 3055, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594345

RESUMO

Providing additional degrees of freedom to manipulate light, spatiotemporal optical vortex (STOV) beams carrying transverse orbital angular momentum are of fundamental importance for spatiotemporal control of light-matter interactions. Unfortunately, existing methods to generate STOV are plagued by various limitations such as inefficiency, bulkiness, and complexity. Here, we theoretically propose and experimentally demonstrate a microscale singlet platform composed of a slanted nanograting to generate STOV. Leveraging the intrinsic topological singularity induced by C2 symmetry and z-mirror symmetry breaking of the slanted nanograting, STOV is generated through the Fourier transform of the spiral phase in the momentum-frequency space to the spatiotemporal domain. In experiments, we observe the space-time evolution of STOV carried by femtosecond pulses using a time-resolved interferometry technique and achieve a generation efficiency exceeding 40%. Our work sheds light on a compact and versatile platform for light pulse shaping, and paves the way towards a fully integrated system for spatiotemporal light manipulation.

3.
ACS Appl Mater Interfaces ; 16(17): 22571-22579, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38640486

RESUMO

Conducting polymer (CP)-based supercapacitors show great promise for applications in the field of wearable and portable electronics. However, these supercapacitors face persistent challenges, notably low energy density and inadequate stability. In this study, we introduce a polythiophene derivative, designated as poly(EPE), synthesized via the electrochemical polymerization of 8-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-3,3-dimethyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine (EPE). The resulting poly(EPE) polymer exhibits an exemplary 3D porous network-like structure, significantly enhancing its capacitance performance. When employed as the electrode material, the symmetric supercapacitor demonstrates an exceptionally high specific capacitance of 1342 F g-1 at a current density of 4.0 A g-1, along with impressive energy and power densities of 119.3 W h kg-1 and 38.83 kW kg-1, respectively. These capacitance values surpass those of previously reported pristine CP-based supercapacitors. Notably, the supercapacitor showcases outstanding stability, maintaining a retention rate of 92.5% even after 50,000 charge-discharge cycles. These findings underscore the substantial potential of poly(EPE) as an electrode material for the advancement of the supercapacitor technology.

4.
Opt Lett ; 49(1): 21-24, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134142

RESUMO

Reconstructive spectrometers/spectral cameras have immense potential for portable applications in various fields, including environmental monitoring, biomedical research and diagnostics, and agriculture and food safety. However, the performance of these spectrometers/spectral cameras is severely limited by the operational bandwidth, spectral diversity, and angle sensitivity of the spectral modulation devices. In this work, we propose a compact spectrometer based on plasmonic metasurfaces that operate across the entire visible wavelength range, covering wavelengths from 400 to 750 nm. We experimentally demonstrate the effective spectral reconstruction achieved by the designed metasurface spectrometer, exhibiting angle tolerance to the incident light within the range of ± 12°. Our results highlight the potential for constructing broadband, large field-of-view hyperspectral cameras.

5.
Nat Commun ; 14(1): 7180, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935685

RESUMO

Polarization, one of the fundamental properties of light, is critical for certain imaging applications because it captures information from the scene that cannot directly be recorded by traditional intensity cameras. Currently, mainstream approaches for polarization imaging rely on strong dichroism of birefringent crystals or artificially fabricated structures that exhibit a high diattenuation typically exceeding 99%, which corresponds to a polarization extinction ratio (PER) >~100. This not only limits the transmission efficiency of light, but also makes them either offer narrow operational bandwidth or be non-responsive to the circular polarization. Here, we demonstrate a single-shot full-Stokes polarization camera incorporating a disordered metasurface array with weak dichroism. The diattenuation of the metasurface array is ~65%, which corresponds to a PER of ~2. Within the framework of compressed sensing, the proposed disordered metasurface array serves as an efficient sensing matrix. By incorporating a mask-aware reconstruction algorithm, the signal can be accurately recovered with a high probability. In our experiments, the proposed approach exhibits high-accuracy full-Stokes polarimetry and high-resolution real-time polarization imaging. Our demonstration highlights the potential of combining meta-optics with reconstruction algorithms as a promising approach for advanced imaging applications.

6.
Front Genet ; 14: 1186862, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323657

RESUMO

Background: Anoikis is a type of apoptosis associated with cell detachment. Resistance to anoikis is a focal point of tumor metastasis. This study aimed to explore the relationship among anoikis-related genes (ARGs), immune infiltration, and prognosis in colorectal cancer (CRC). Methods: The transcriptome profile and clinical data on patients with CRC were retrieved from The Cancer Genome Atlas and Gene Expression Omnibus databases. Patients were divided into two clusters based on the expression of ARGs. Differences between the two ARG molecular subtypes were analyzed in terms of prognosis, functional enrichment, gene mutation frequency, and immune cell infiltration. An ARG-related prognostic signature for predicting overall survival in patients with CRC was developed and validated using absolute value convergence and selection operator (LASSO) regression analysis. The correlation between the signature risk score and clinicopathological features, immune cell infiltration, immune typing, and immunotherapy response was analyzed. The risk score combined with clinicopathological characteristics was used to construct a nomogram to assess CRC patients' prognosis. Results: Overall, 151 ARGs were differentially expressed in CRC. Two ARG subtypes, namely, ARG-high and ARG-low groups, were identified and correlated with CRC prognosis. The gene mutation frequency and immune, stromal, and ESTIMATE scores of the ARG-high group were higher than those of the ARG-low group. Moreover, CD8, natural killer cells, M1 macrophages, human leukocyte antigen (HLA), and immune checkpoint-related genes were significantly increased in the ARG-high group. An optimized 25-gene CRC prognostic signature was successfully constructed, and its prognostic predictive ability was validated. The high-risk score was correlated with T, N, M, and TNM stages. Risk scores were negatively correlated with dendritic cells, eosinophils, and CD4 cells, and significantly positively correlated with regulatory T cells. Patients in the high-risk group were more likely to exhibit immune unresponsiveness. Finally, the nomogram model was constructed and showed good prognostic predictive power. Conclusion: ARGs are associated with clinicopathological features and the prognosis of CRC, and play important roles in the immune microenvironment. Herein, we underpinned the usefulness of ARGs in CRC to develop more effective immunotherapy techniques.

7.
Opt Lett ; 48(7): 1722-1725, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221750

RESUMO

Polarizing beam splitters (PBSs) play an important role in applications requiring polarization multiplexing or high polarization purity. Traditional prism-based PBSs usually have large volumes, which hampers their further applications in ultracompact integrated optical systems. Here, we demonstrate a single-layer silicon metasurface-based PBS with the ability to deflect two orthogonally linearly polarized infrared light beams to on-demand angles. The metasurface consists of silicon anisotropic microstructures, which can provide different phase profiles for the two orthogonal polarization states. In experiments, two metasurfaces designed with arbitrary deflection angles for x- and y-polarized light exhibit good splitting performance at an infrared wavelength of 10 µm. We envision that this type of planar and thin PBS can be used in a series of compact thermal infrared systems.

8.
Nano Lett ; 23(7): 2991-2997, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36971648

RESUMO

Spiral phase contrast imaging and bright-field imaging are two widely used modes in microscopy, providing distinct morphological information about objects. However, conventional microscopes are always unable to operate with these two modes at the same time and need additional optical elements to switch between them. Here, we present a microscopy setup that incorporates a dielectric metasurface capable of achieving spiral phase contrast imaging and bright-field imaging synchronously. The metasurface not only can focus the light for diffraction-limited imaging but also can perform a two-dimensional spatial differentiation operation by imparting an orbital angular momentum to the incident light field. This allows two spatially separated images to be simultaneously obtained, one containing high-frequency edge information and the other showing the entirety of the object. Combined with the advantages of planar architecture and ultrathin thickness of the metasurface, this approach is expected to provide support in the fields of microscopy, biomedicine, and materials science.

9.
Front Oncol ; 12: 850242, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158665

RESUMO

Objective: We conducted a phase 2 trial to compare the safety and efficacy of intravenous paclitaxel or intraperitoneal paclitaxel plus mFOLFOX6 vs. mFOLFOX6 in untreated advanced gastric cancer. Methods: Participants with untreated advanced gastric cancer were randomly assigned (1:1:1) to: intravenous paclitaxel 135 mg/m2 or intraperitoneal paclitaxel 80 mg/m2 plus mFOLFOX6 omitting bolus fluorouracil; or mFOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, fluorouracil 400 mg/m2 bolus, fluorouracil 2,400 mg/m2 46-h continuous infusion). Treatment was every 14 days for up to 9 cycles followed by S-1 maintenance. The primary outcome was progression-free survival. Results: Of 90 enrolled participants, 30 in the intravenous paclitaxel group, 29 in the intraperitoneal paclitaxel group, and 30 in the mFOLFOX6 group were included in the analyses. The median progression-free survival was 6.52, 5.83, and 4.55 months, respectively, for the intravenous paclitaxel group, intraperitoneal paclitaxel group, and mFOLFOX6 group. The hazard ratios were 0.56 (95% CI: 0.33-0.94; p = 0.026) and 0.56 (95% CI: 0.33-0.96; p = 0.037), respectively, for the intravenous paclitaxel group and the intraperitoneal paclitaxel group vs. the mFOLFOX6 group. The most common grade 3/4 adverse events for the intravenous paclitaxel group, intraperitoneal paclitaxel group, and mFOLFOX6 group, respectively, were neutropenia (30.0%, 34.5%, 33.3%), diarrhea (13.3%, 20.7%, 13.3%), and leukopenia (10.0%, 13.8%, 10.0%). No treatment-related death occurred. Conclusion: The findings of this phase 2 trial suggest that adding intravenous paclitaxel or intraperitoneal paclitaxel to mFOLFOX6 for untreated advanced gastric cancer improved progression-free survival with manageable adverse events.

10.
J Int Med Res ; 48(9): 300060520953315, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32938273

RESUMO

PURPOSE: To characterize the pattern of post-mastectomy supraclavicular lymph node (LN) metastases in patients with breast cancer (BC) and to provide insights for individualized clinical target volume delineation for radiotherapy. METHODS: We retrospectively analyzed 88 patients with BC who developed post-mastectomy regional LN metastases. The affected regional LNs were categorized as the ipsilateral medial supraclavicular LN area (IMSC-LN), ipsilateral lateral supraclavicular LN area (ILSC-LN), ipsilateral infraclavicular LN area (IIC-LN), and ≥2 groups in the ipsilateral clavicular LN area (MMIC-LN). Clinical characteristics were included in a multivariate analysis to identify risk factors for clavicular LN metastases. RESULTS: The ILSC-LNs (68.2%) were the most common metastatic site. IMSC-LN metastases showed a significant association with estrogen-receptor (ER) negative status, left-sided BC, and positive axillary LNs. Tumor size ≥2.4 cm and Her2 type were predictors of ILSC-LN metastases. Additionally, tumor size ≥2.4 cm, and level I ipsilateral axillary metastases were associated with MMIC-LN metastasis. CONCLUSION: ILSC-LN was the most frequently affected group of supraclavicular lymph nodes. ER-negative status, left-sided BC, tumor size, and positive ipsilateral axillary LNs are potentially associated with the pattern of supraclavicular LN metastatic involvement.


Assuntos
Neoplasias da Mama , Metástase Linfática , Mastectomia , Axila/patologia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Linfonodos/patologia , Linfonodos/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
11.
Phys Rev Lett ; 125(26): 267402, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449781

RESUMO

Exquisite polarization control using optical metasurfaces has attracted considerable attention thanks to their ability to manipulate multichannel independent wavefronts with subwavelength resolution. Here we present a new class of metasurface polarization optics, which enables imposition of two arbitrary and independent amplitude profiles on any pair of orthogonal states of polarization. The implementation method involves a polarization-dependent interference mechanism achieved by constructing a metasurface composed of an array of nanoscale birefringent waveplates. Based on this principle, we experimentally demonstrate chiral grayscale metasurface and chiral shadow rendering of structured light. These results illustrate a general approach interlinking amplitude profiles and orthogonal states of polarization and expands the scope of metasurface polarization shaping optics.

12.
Biomed Res Int ; 2016: 5382047, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27738632

RESUMO

Purpose. This study aimed to evaluate the characteristics of the HVGGSSV peptide, exploring radiation-guided delivery in a mouse model of nasopharyngeal carcinoma. Methods. Mice with CNE-1 nasopharyngeal carcinoma were assigned to two different groups treated with Cy7-NHS and Cy7-HVGGSSV, respectively. Meanwhile, each mouse received a single dose of 3 Gy radiation. Biological distribution of the recombinant peptide was assessed on an in vivo small animal imaging system. Results. The experimental group showed maximum fluorescence intensity in irradiated tumors treated with Cy7-labeled HVGGSSV, while untreated (0 Gy) control tumors showed lower intensity levels. Fluorescence intensities of tumors in the right hind limbs of experimental animals were 7.84 × 107 ± 1.13 × 107, 1.35 × 108 ± 2.66 × 107, 4.05 × 108 ± 1.75 × 107, 5.57 × 108 ± 3.47 × 107, and 9.26 × 107 ± 1.73 × 107 photons/s/cm2 higher compared with left hind limb values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence intensities of tumor in the right hind limbs of the experimental group were 1.66 × 108 ± 1.71 × 107, 1.51 × 108 ± 3.23 × 107, 5.38 × 108 ± 1.96 × 107, 5.89 × 108 ± 3.57 × 107, and 1.62 × 108 ± 1.69 × 107 photons/s/cm2 higher compared with control group values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence was not specifically distributed in the control group. Compared with low fluorescence intensity in the heart, lungs, and tumors, high fluorescence distribution was found in the liver and kidney at 48 h. Conclusions. HVGGSSV was selectively bound to irradiated nasopharyngeal carcinoma, acting as a targeting transport carrier for radiation-guided drugs that are mainly metabolized in the kidney and liver.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Raios gama , Neoplasias Nasofaríngeas/terapia , Neoplasias Experimentais/terapia , Peptídeos/farmacologia , Animais , Carcinoma , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
13.
Mol Cell Biochem ; 311(1-2): 179-87, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18228117

RESUMO

Chronic cardiac ischemia/hypoxia induces coronary collateral formation and cardiomyocyte proliferation. Hypoxia can induce cellular adaptive responses, such as synthesis of VEGF for angiogenesis and IGF-2 for proliferation. Both reduce apoptotic effects to minimize injury or damage. To investigate the mechanism of neoangiogenesis and proliferation of fetal heart under umbilical cord compression situation, we used H9c2 cardiomyoblast cell culture, and in vivo embryonic hearts as our study models. Results showed hypoxia induced not only the increase of IGF-2 and VEGF expression but also the activation of their upstream regulatory genes, HIF-1alpha and Shh. The relationship between HIF-1alpha and Shh was further studied by using cyclopamine and 2-ME2, inhibitor of Shh and HIF-1alpha signaling, respectively, in the cardiomyoblast cell culture under hypoxia. We found that the two inhibitors not only blocked their own signal pathway, but also inhibited each other. The observations revealed when fetal heart under hypoxia that HIF-1alpha and Shh pathways maybe involve in cell proliferation and neoangiogenesis to minimize injury or damage, whereas the complex cross-talk between the two pathways remains unknown.


Assuntos
Embrião de Mamíferos , Coração/embriologia , Proteínas Hedgehog/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia , Isquemia Miocárdica/metabolismo , Miocárdio , Animais , Células Cultivadas , Embrião de Mamíferos/anatomia & histologia , Embrião de Mamíferos/fisiologia , Feminino , Proteínas Hedgehog/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Camundongos , Miocárdio/citologia , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Gravidez , Ratos , Receptores de Somatomedina/genética , Receptores de Somatomedina/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
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