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1.
Phys Rev Lett ; 132(16): 160801, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701444

RESUMO

A solid-state approach for quantum networks is advantageous, as it allows the integration of nanophotonics to enhance the photon emission and the utilization of weakly coupled nuclear spins for long-lived storage. Silicon carbide, specifically point defects within it, shows great promise in this regard due to the easy of availability and well-established nanofabrication techniques. Despite of remarkable progresses made, achieving spin-photon entanglement remains a crucial aspect to be realized. In this Letter, we experimentally generate entanglement between a silicon vacancy defect in silicon carbide and a scattered single photon in the zero-phonon line. The spin state is measured by detecting photons scattered in the phonon sideband. The photonic qubit is encoded in the time-bin degree of freedom and measured using an unbalanced Mach-Zehnder interferometer. Photonic correlations not only reveal the quality of the entanglement but also verify the deterministic nature of the entanglement creation process. By harnessing two pairs of such spin-photon entanglement, it becomes straightforward to entangle remote quantum nodes at long distance.

2.
Phys Rev Lett ; 132(8): 083601, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457704

RESUMO

Quantum non-Gaussianity, a more potent and highly useful form of nonclassicality, excludes all convex mixtures of Gaussian states and Gaussian parametric processes generating them. Here, for the first time, we conclusively test quantum non-Gaussian coincidences of entangled photon pairs with the Clauser-Horne-Shimony-Holt-Bell factor S=2.328±0.004 from a single quantum dot with a depth up to 0.94±0.02 dB. Such deterministically generated photon pairs fundamentally overcome parametric processes by reducing crucial multiphoton errors. For the quantum non-Gaussian depth of the unheralded (heralded) single-photon state, we achieve the value of 8.08±0.05 dB (19.06±0.29 dB). Our Letter experimentally certifies the exclusive quantum non-Gaussianity properties highly relevant for optical sensing, communication, and computation.

3.
Orthop Surg ; 16(2): 462-470, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086608

RESUMO

OBJECTIVE: Osteosarcoma is a primary malignancy originating from mesenchymal tissue characterized by rapid growth, early metastasis and poor prognosis. Ginsenoside Rg5 (G-Rg5) is a minor ginsenoside extracted from Panax ginseng C.A. Meyer which has been discovered to possess anti-tumor properties. The objective of current study was to explore the mechanism of G-Rg5 in the treatment of osteosarcoma by network pharmacology and molecular docking technology. METHODS: Pharmmapper, SwissTargetPrediction and similarity ensemble approach databases were used to obtain the pharmacological targets of G-Rg5. Related genes of osteosarcoma were searched for in the GeneCards, OMIM and DrugBank databases. The targets of G-Rg5 and the related genes of osteosarcoma were intersected to obtain the potential target genes of G-Rg5 in the treatment of osteosarccoma. The STRING database and Cytoscape 3.8.2 software were used to construct the protein-protein interaction (PPI) network, and the Database for Annotation, Visualization and Integrated Discovery (DAVID) platform was used to perform gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. AutoDock vina software was used to perform molecular docking between G-Rg5 and hub targets. The hub genes were imported into the Kaplan-Meier Plotter online database for survival analysis. RESULTS: A total of 61 overlapping targets were obtained. The related signaling pathways mainly included PI3K-Akt signaling pathway, Proteoglycans in cancer, Lipid and atherosclerosis and Kaposi sarcoma-associated herpesvirus infection. Six hub targets including PIK3CA, SRC, TP53, MAPK1, EGFR, and VEGFA were obtained through PPI network and targets-pathways network analyses. The results of molecular docking showed that the binding energies were all less than -7 kcal/mol. And the results of survival analysis showed TP53 and VEGFA affect the prognosis of sarcoma patients. CONCLUSION: This study explored the possible mechanism of G-Rg5 in the treatment of osteosarcoma using network pharmacology method, suggesting that G-Rg5 has the characteristics of multi-targets and multi-pathways in the treatment of osteosarcoma, which lays a foundation for the follow-up experimental and clinical researches on the therapeutic effects of G-Rg5 on osteosarcoma.


Assuntos
Neoplasias Ósseas , Medicamentos de Ervas Chinesas , Ginsenosídeos , Osteossarcoma , Humanos , Simulação de Acoplamento Molecular , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/tratamento farmacológico
4.
Phys Rev Lett ; 131(13): 133601, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37831993

RESUMO

Berry curvature is a fundamental element to characterize topological quantum physics, while a full measurement of Berry curvature in momentum space was not reported for topological states. Here we achieve two-dimensional Berry curvature reconstruction in a photonic quantum anomalous Hall system via Hall transport measurement of a momentum-resolved wave packet. Integrating measured Berry curvature over the two-dimensional Brillouin zone, we obtain Chern numbers corresponding to -1 and 0. Further, we identify bulk-boundary correspondence by measuring topology-linked chiral edge states at the boundary. The full topological characterization of photonic Chern bands from Berry curvature, Chern number, and edge transport measurements enables our photonic system to serve as a versatile platform for further in-depth study of novel topological physics.

5.
Opt Lett ; 48(13): 3507-3510, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390167

RESUMO

The refractive index is a critical parameter in optical and photonic device design. However, due to the lack of available data, precise designs of devices working in low temperatures are still frequently limited. In this work, we have built a homemade spectroscopic ellipsometer (SE) and measured the refractive index of GaAs at a matrix of temperatures (4 K < T < 295 K) and photon wavelengths (700 nm < λ < 1000 nm) with a system error of ∼0.04. We verified the credibility of the SE results by comparing them with afore-reported data at room temperature and with higher precision values measured by vertical GaAs cavity at cryogenic temperatures. This work makes up for the lack of the near-infrared refractive index of GaAs at cryogenic temperatures and provides accurate reference data for semiconductor device design and fabrication.


Assuntos
Fótons , Refratometria , Temperatura , Semicondutores
6.
Sci Bull (Beijing) ; 68(8): 807-812, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36990872

RESUMO

Semiconductor quantum dots, as promising solid-state platform, have exhibited deterministic photon pair generation with high polarization entanglement fidelity for quantum information applications. However, due to temporal correlation from inherently cascaded emission, photon indistinguishability is limited, which restricts their potential scalability to multi-photon experiments. Here, by utilizing quantum interferences to decouple polarization entanglement from temporal correlation, we improve four-photon Greenberger-Horne-Zeilinger (GHZ) state entanglement fidelity from (58.7±2.2)% to (75.5±2.0)%. Our work paves the way to realize scalable and high-quality multi-photon states from quantum dots.

7.
Mar Drugs ; 20(11)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36355019

RESUMO

Phycocyanin is an excellent antioxidant with anti-inflammatory effects on which recent studies are growing; however, its specific target remains unclear. Linear tetrapyrrole compounds such as bilirubin have been shown to lead to the induction of heme oxygenase 1 expression in vivo, thus achieving antioxidant and anti-inflammatory effects. Phycocyanin is bound internally with linear tetrapyrrole phycocyanobilin in a similar structure to bilirubin. We speculate that there is probably a way of inducing the expression of heme oxygenase 1, with which tissue oxidative stress and inflammation can be inhibited, thus inhibiting pulmonary fibrosis caused by oxidative damage and inflammation of lung. By optimizing the enzymatic hydrolysis process, phycocyanobilin-bound phycocyanin peptide were obtained, and its in vitro antioxidant, anti-inflammatory, and anti-pulmonary fibrosis activities were investigated. The results show that the phycocyanobilin peptide was able to alleviate oxidative and inflammatory damage in cells through the Keap1-Nrf2-HO-1 pathway, which in turn relieved pulmonary fibrosis symptoms.


Assuntos
Heme Oxigenase-1 , Ficocianina , Humanos , Ficocianina/farmacologia , Ficocianina/uso terapêutico , Ficocianina/metabolismo , Heme Oxigenase-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Antioxidantes/metabolismo , Estresse Oxidativo , Inflamação/tratamento farmacológico , Bilirrubina/metabolismo , Bilirrubina/farmacologia , Bilirrubina/uso terapêutico , Anti-Inflamatórios/farmacologia , Tetrapirróis/farmacologia , Tetrapirróis/uso terapêutico , Fibrose
8.
Mol Biol Rep ; 49(8): 7899-7909, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35708862

RESUMO

BACKGROUND: Trophinin-associated protein (TROAP) mediates embryonic transfer, regulates microtubules, and is associated with the biological behavior of various cancers. However, there is limited information on the role of TROAP in glioma. METHODS AND RESULTS: We obtained clinical information on 1948 patients with glioma from The Cancer Genome Atlas, Gene Expression Omnibus and the Chinese Glioma Genome Atlas. Basal assays were used to measure changes in TROAP expression levels in high-grade glioma cell lines and in normal human astrocytes. Quantitative reverse transcription polymerase chain reaction assays showed that TROAP expression was higher in glioma cell lines than in normal astrocytes. The expression level of TROAP in 749 glioma was significantly higher than that in 228 normal brain tissues using Student's t test. The expression of TROAP has a positive relationship with the clinical characteristics of poor prognosis, such as WHO grade, age and has negatively correlated with the indicators of beneficial prognosis, such as IDH mutation and 1p19q co-deletion. Kaplan-Meier survival curves, single multifactor analysis were used to analyze correlations between TROAP and clinical features and prognosis of gliomas. In addition, TROAP overexpression was an independent risk factor for glioma and was associated with reduced overall survival of patients with glioma particularly in patients with WHO grade III and grade IV glioma. Gene set enrichment analysis showed that homologous recombination, cell cycle, and p53 signaling pathways were enriched in samples overexpressing TROAP. CONCLUSION: TROAP is a potential risk factor associated with poor prognosis in patients with glioma and may act as a highly specific biomarker, offering the possibility of individualized glioma treatment.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Ciclo Celular , Glioma/metabolismo , Humanos , Estimativa de Kaplan-Meier
9.
Eur J Med Chem ; 228: 114031, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34875520

RESUMO

Alzheimer's disease (AD) possesses a complex pathogenetic mechanism. Nowadays, multitarget agents are considered to have potential in effectively treating AD via triggering molecules in functionally complementary pathways at the same time. Here, based on the screening (∼1400 compounds) against neuroinflammation, an imidazolylacetophenone oxime ether (IOE) was discovered as a novel hit. In order to obtain SARs, a series of imidazolylacetophenone oxime derivatives were constructed, and their C=N bonds were confirmed as the Z configuration by single crystals. These derivatives exhibited potential multifunctional neuroprotective effects including anti-neuroinflammatory, antioxidative damage, metal-chelating, inhibition of acetylcholinesterase (AChE) properties. Among these derivatives, compound 12i displayed the most potent inhibitory activity against nitric oxide (NO) production with EC50 value of 0.57 µM 12i can dose-dependently suppress the expression of iNOS and COX-2 but not change the expression of HO-1 protein. Moreover, 12i exhibited evidently neuroprotective effects on H2O2-induced PC12 cells damage and ferroptosis without cytotoxicity at 10 µM, as well as selectively metal chelating properties via chelating Cu2+. In addition, 12i showed a mixed-type inhibitory effect on AChE in vitro. The structure-activity relationships (SARs) analysis indicated that dioxolane groups on benzene ring and rigid oxime ester can improve the activity. Parallel artificial membrane permeation assay (PAMPA) also verified that 12i can overcome the blood-brain barrier (BBB). Overall, this is the first report on imidazolylacetophenone oxime-based multifunctional neuroprotective effects, suggesting that this type of compounds might be novel multifunctional agents against AD.


Assuntos
Acetofenonas/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Fármacos Neuroprotetores/farmacologia , Oximas/farmacologia , Acetofenonas/síntese química , Acetofenonas/química , Acetilcolinesterase/metabolismo , Animais , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Electrophorus , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Imidazóis/síntese química , Imidazóis/química , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Oximas/síntese química , Oximas/química , Picratos/antagonistas & inibidores , Ratos , Relação Estrutura-Atividade
10.
Biomed Pharmacother ; 146: 112583, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34954644

RESUMO

Andrographis paniculata (A. paniculata) is a traditional herbal medicine that has been widely used in Asian countries for hundreds of years. Andrographolide (AG) is a diterpene lactone extracted from A. paniculata. Owing to the in-depth study of pharmacological mechanisms, the therapeutic potential of AG, including its anti-inflammatory, anti-tumor, and immunoregulatory attributes, has attracted the attention of many researchers. Studies testing the therapeutic effects of AG have demonstrated desirable results in the treatment of a variety of clinical diseases. With high safety and various biological functions, AG might be a promising candidate for the treatment of musculoskeletal disorders. Here, we review all available literatures to summarize the pharmacological effects of AG and facilitate further researches on musculoskeletal diseases.


Assuntos
Diterpenos/farmacologia , Doenças Musculoesqueléticas/patologia , Andrographis paniculata , Animais , Artrite/patologia , Linhagem Celular , Diterpenos/efeitos adversos , Diterpenos/farmacocinética , Interações Medicamentosas , Humanos , Degeneração do Disco Intervertebral/patologia , Medicina Tradicional , Osteoporose/patologia
11.
Mar Drugs ; 19(8)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34436300

RESUMO

Sea cucumbers are a class of marine invertebrates and a source of food and drug. Numerous microorganisms are associated with sea cucumbers. Seventy-eight genera of bacteria belonging to 47 families in four phyla, and 29 genera of fungi belonging to 24 families in the phylum Ascomycota have been cultured from sea cucumbers. Sea-cucumber-associated microorganisms produce diverse secondary metabolites with various biological activities, including cytotoxic, antimicrobial, enzyme-inhibiting, and antiangiogenic activities. In this review, we present the current list of the 145 natural products from microorganisms associated with sea cucumbers, which include primarily polyketides, as well as alkaloids and terpenoids. These results indicate the potential of the microorganisms associated with sea cucumbers as sources of bioactive natural products.


Assuntos
Produtos Biológicos , Fungos/metabolismo , Pepinos-do-Mar/microbiologia , Animais , Organismos Aquáticos
12.
Phys Rev Lett ; 127(3): 030402, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34328769

RESUMO

We propose a new method to directly measure a general multiparticle quantum wave function, a single matrix element in a multi-particle density matrix, by quantum teleportation. The density matrix element is embedded in a virtual logical qubit and is nondestructively teleported to a single physical qubit for readout. We experimentally implement this method to directly measure the wave function of a photonic mixed quantum state beyond a single photon using a single observable for the first time. Our method also provides an exponential advantage over the standard quantum state tomography in measurement complexity to fully characterize a sparse multiparticle quantum state.

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