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1.
Biochim Biophys Acta Mol Cell Res ; 1870(1): 119381, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36265657

RESUMO

Endometriosis, characterized by ectopic endometrium growth in the extrauterine environment, is one of the most notable diseases of the female reproductive system. Worldwide, endometriosis affects nearly 10 % of women in their reproductive years and causes a significant decline in quality of life. Despite extensive investigations of endometriosis over the past years, the mechanisms of endometriosis pathogenesis remain unclear. In recent years, metabolic factors have increasingly been considered factors in endometriosis. There is compelling evidence regarding the progress of endometriosis in the context of severe metabolic dysfunction. Hence, the curative strategies and ongoing attempts to conquer endometriosis might start with metabolic pathways. This review focuses on metabolic mechanisms and summarizes current research progress. These findings provide valuable information for the non-intrusive diagnosis of the disease and may contribute to the understanding of the pathogenesis of endometriosis.


Assuntos
Endometriose , Feminino , Humanos , Endometriose/etiologia , Endometriose/metabolismo , Endometriose/patologia , Qualidade de Vida , Endométrio/metabolismo
2.
Ultrasonics ; 128: 106856, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36242803

RESUMO

In this work, a circular statistics vector (CSV) weighting Fourier domain (FD) beamforming for ultrasound plane-wave images was proposed to achieve better image quality with a high frame rate. Firstly, the cosine and sine components of the instantaneous phase are extracted from undelayed RF signals. Secondly, the FD beamformed cosine and sine components are used to establish the CSV. Finally, the FD beamformed amplitude image is weighted by the CSV. The resolution, contrast, and computation complexity were used to assess the performance of the proposed method. The results revealed that FD_CSV could significantly reduce the computational load compared to the conventional DAS_CSV on the equal improvement of image quality. Besides, compared to coherence factor (CF), phase coherence factor (PCF), etc., based on variance calculation, the CSV based on mean resultant vector calculation can effectively preserve the speckle due to the more tolerant to phase errors. The proposed FD_CSV weighting method has successfully conducted high image quality and low computational load.


Assuntos
Algoritmos , Ondas Ultrassônicas , Imagens de Fantasmas , Ultrassonografia/métodos , Processamento de Imagem Assistida por Computador/métodos
3.
Microbiol Spectr ; : e0346822, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36354336

RESUMO

The appearance and prevalence of novel plasmid-encoded tigecycline resistance efflux pump gene clusters tmexC1D1-toprJ1 and tmexC2D2-toprJ2 in Enterobacteriaceae have raised a threat to public health. Here, another tigecycline resistance gene cluster, tmexC2D2.2-toprJ2, was identified in two Aeromonas isolates recovered from fish meat and vegetables. Cloning confirmed the expression of tmexC2D2.2-toprJ2 mediated the resistance to tigecycline and decreased susceptibility to tetracyclines and cephalosporins in both Escherichia coli and Aeromonas. In an Aeromonas veronii strain, four copies of tmexC2D2.2-toprJ2 were located on the chromosome. Further analysis revealed that tmexC2D2.2-toprJ2 has been detected in the chromosomes of A. veronii, Aeromonas hydrophila, and Aeromonas caviae with one to four copies due to the insertion of a potential integrative transferable unit. The occurrence of multiple copies of chromosomal tmexC2D2.2-toprJ2 may act as a sink for this tigecycline resistance gene cluster, which requires continuous monitoring. IMPORTANCE Tigecycline is regarded as one of the few effective drugs against multidrug-resistant bacterial infection. However, mobile tigecycline resistance efflux pump gene clusters such as tmexC1D1-toprJ1 and its variants have been identified in both animal- and human-origin Enterobacteriaceae. In this study, we first found another efflux pump gene cluster, tmexC2D2.2-toprJ2, in the Aeromonas chromosome. This gene cluster could mediate tigecycline resistance and decrease susceptibility to tetracyclines and cephalosporins in the Aeromonas host strain. Meanwhile, tmexC2D2.2-toprJ2 was detected with multiple copies in Aeromonas spp. This multidrug resistance efflux pump gene cluster with multiple copy numbers might stably exist in Aeromonas and serve as a reservoir for tmexCD2-toprJ2, facilitating its persistent presence and spread.

4.
ACS Appl Mater Interfaces ; 14(46): 52262-52269, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36373964

RESUMO

Solution-processed polycrystalline perovskites (PVKs) have aroused tremendous interest in the optoelectronic device field. However, the inherent high-density defects in the polycrystalline hindered achieving efficient and stable large-area PVK solar cells (PSCs). Although organic molecules are already employed to passivate PVK defects, they are insulating by nature, limiting the carrier transport. Here, we design an assembly of a small molecule (N,N'-di(propanoic acid)-perylene-3,4,9,10-tetracarboxylic diamide, PDI) via confinement-assisted supramolecular polymerization technology, which is used as a binder for grain boundaries to simultaneously passivate defects and promote carrier transport. The synergistic effect allows the efficiency of all-air processed carbon-based PSCs to reach a decent power conversion efficiency of 14.17%. Importantly, the as-prepared supramolecular assembly completely breaks through the insulating nature of the single molecule, which exists in the long-term defect passivation of PSCs by organic molecules. It is expected that this finding may provide novel design ideas to apply the assemblies to improve the performance of PSCs.

5.
Chin J Integr Med ; 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36374440

RESUMO

OBJECTIVE: To observe the clinical efficacy of transcutaneous electrical acupoint stimulation (TEAS) combined with warm acupuncture in treating breast cancer associated with upper limb lymphedema (BCRL). METHODS: This was a retrospective cohort study using a paired control design. Fifty-two BCRL patients were assigned to the control group (27 cases) and the treatment group (25 cases). The patients in the control group were treated with lymphedema comprehensive detumescence treatment (CDT) for 4 weeks, including systematic therapy composed of manual lymphatic drainage, compression bandage, skincare, and functional exercise. The patients in the treatment group were treated with TEAS combined with warm acupuncture based on the control group methods. Each treatment lasted for 30 min and was applied twice a week for 4 weeks. The arm circumference (AC) of different positions of the affected limb and the degree of swelling of the affected limb were evaluated before the first treatment and after the last treatment. The clinical efficacy was evaluated according to the degree of edema before and after treatment. All adverse events during treatment were recorded. RESULTS: The patients' AC and the swelling feeling of the affected limb in the treatment group and the control group were both reduced compared with those before treatment. Compared with the control group, AC of the wrist joint transverse stria, the midpoint between the wrist joint transverse stria and the elbow joint transverse stria in the treatment group were significantly reduced (P<0.05). The decrease in AC diameter at the midpoint between the elbow joint transverse stria and the axillary transverse stria was the most significant (P<0.01). The swelling degree of the affected limbs in the treatment group was significantly lower than before treatment, and was significantly lower compared with the control group after treatment (P<0.01). The total effective rate was 72% in the treatment group, significantly higher than that in the control group (55.56%, P<0.05). No serious adverse events occured in either group. CONCLUSIONS: TEAS combined with warm acupuncture can effectively reduce AC and swelling feeling of the affected limb in patients with BCRL. The effect is better than that of CDT therapy alone. (Registration No. ChiCTR2200062075).

6.
Ageing Res Rev ; 83: 101785, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36371015

RESUMO

Age-related diseases have become more common with the advancing age of the worldwide population. Such diseases involve multiple organs, with tissue degeneration and cellular apoptosis. To date, there is a general lack of effective drugs for treatment of most age-related diseases and there is therefore an urgent need to identify novel drug targets for improved treatment. Acid-sensing ion channel 1a (ASIC1a) is a degenerin/epithelial sodium channel family member, which is activated in an acidic environment to regulate pathophysiological processes such as acidosis, inflammation, hypoxia, and ischemia. A large body of evidence suggests that ASIC1a plays an important role in the development of age-related diseases (e.g., stroke, rheumatoid arthritis, Huntington's disease, and Parkinson's disease.). Herein we present: 1) a review of ASIC1a channel properties, distribution, and physiological function; 2) a summary of the pharmacological properties of ASIC1a; 3) and a consideration of ASIC1a as a potential therapeutic target for treatment of age-related disease.

7.
iScience ; 25(11): 105363, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36339263

RESUMO

Endometriosis is a common chronic condition characterized by abnormal growth of the endometrium outside the uterus. Heat shock transcription factor 1 (HSF1) is a significant regulator of the proteotoxic stress response and plays an essential role in developing endometriosis. However, the mechanisms regulating HSF1 protein stability in endometriosis remain unclear. Here, we demonstrate that OTUB1 interacts with HSF1 and promotes HSF1 protein stability through deubiquitination. In addition, OTUB1 enhances glycolysis and epithelial-mesenchymal transition of endometriosis cells, leading to promote proliferation, migration, and invasion of endometriosis cells. The progression of endometriosis is inhibited in an OTUB1-knockout mouse model. In summary, OTUB1 promotes the development of endometriosis by up-regulating HSF1. OTUB1/HSF1 axis may become a new therapeutic target for endometriosis.

8.
Anal Chem ; 94(47): 16461-16469, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36383051

RESUMO

The combination of gold nanoclusters (AuNCs) with surface plasmonic metal nanomaterials is an effective and direct method to improve the photoluminescence efficiency of AuNCs. However, the plasmon-enhanced AuNC luminescence strategies usually utilize silica as the separation layer, which requires further functionalization because the silica layer has no functional groups for in situ bonding of AuNCs. Therefore, it appears as a crucial need to develop an appropriate separation layer for the preparation of plasmon-enhanced AuNC luminescent nanomaterials. In this work, employing bovine serum albumin (BSA) as a novel separation layer, we prepared gold nanoparticles (AuNPs)@BSA@Au35NCs by a controllable and in situ synthesis method. BSA can form a BSA layer on the surface of AuNPs through Au-S bonds. Meanwhile, BSA can reduce AuCl4- ions to generate Au35NCs. In comparison with pure BSA-AuNCs, the quantum yield of the AuNPs@BSA@Au35NCs was increased by nearly 7 times as a result of plasmonic coupling, and the time of in situ synthesis of Au35NCs was shortened by 8 h. More importantly, the preparation of the BSA layer was simple and time-saving without functionalization, in contrast to the previously reported silica layer. Moreover, the simulation calculation of different dimensions determined the optimal binding sites between Au35NCs and BSA, confirming that BSA can be an effective spatial spacer. Finally, it was found that the BSA layer between AuNPs and AuNCs can improve the specificity of AuNCs toward H2S, which is extremely difficult for pure BSA@AuNCs.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ouro/química , Soroalbumina Bovina/química , Nanopartículas Metálicas/química , Corantes , Dióxido de Silício , Espectrometria de Fluorescência
9.
Front Endocrinol (Lausanne) ; 13: 1027603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36325458

RESUMO

Objective: To explore the global research trends and hotspots of steroid-induced osteonecrosis of the femoral head (SONFH) through qualitative and quantitative analysis of bibliometrics. Methods: All publications on SONFH published from 1992 to 2021 were extracted from the Web of Science Core Collection database. CiteSpace was used for the visualization analysis of major countries, active institutions, productive authors, and the burst of keywords. VOSviewer was used for coupling analysis of countries/regions, institutions, and authors. Microsoft Excel 2017 was used for statistical analysis, drawing bar charts, pie charts, and cumulative area charts. The software of MapInfo was used to draw the distribution map of the publications. Results: A total of 780 publications were included for analyses. The most productive year was 2020 with 98 records. China was the most influential country with 494 publications, an H-index of 59, and total citations of 16820. The most prolific institution was Shanghai Jiaotong University in China with 53 publications and 998 citations. Clinical Orthopaedics and Related Research (IF = 4.755, 2021) was the most active journal with 26 articles. The hot keywords were "osteonecrosis", "avascular necrosis", "osteogenic differentiation", "proliferation", "PPAR gamma", "apoptosis", "oxidative stress", "genetic polymorphism" and "mesenchymal stem cells". The keywords like "proliferation", "PPAR gamma" and "genome-wide" have emerged in recent years. Conclusion: The number of publications in SONFH has increased significantly in the last three decades. The pathologic mechanism of SONFH gathered most research interests. Genomics and cell molecular biology of SONFH are the research frontiers.


Assuntos
Cabeça do Fêmur , Receptores Ativados por Proliferador de Peroxissomo , Humanos , China , Bibliometria , Esteroides
10.
J Chem Theory Comput ; 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384001

RESUMO

Accurate prediction of the pKa's of protein residues is crucial to many applications in biological simulation and drug discovery. Here, we present the use of free energy perturbation (FEP) calculations for the prediction of single-protein residue pKa values. We begin with an initial set of 191 residues with experimentally determined pKa values. To isolate sampling limitations from force field inaccuracies, we develop an algorithm to classify residues whose environments are significantly affected by crystal packing effects. We then report an approach to identify buried histidines that require significant sampling beyond what is achieved in typical FEP calculations. We therefore define a clean data set not requiring algorithms capable of predicting major conformational changes on which other pKa prediction methods can be tested. On this data set, we report an RMSE of 0.76 pKa units for 35 ASP residues, 0.51 pKa units for 44 GLU residues, and 0.67 pKa units for 76 HIS residues.

11.
Opt Express ; 30(14): 25308-25317, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237063

RESUMO

Electro-optic (EO) modulators with a high modulation bandwidth are indispensable parts of an optical interconnect system. A key requirement for an energy-efficient EO modulator is the low drive voltage, which can be provided using a standard complementary metal oxide semiconductor circuity without an amplifying driver. Thin-film lithium niobate has emerged as a new promising platform, and shown its capable of achieving driverless and high-speed EO modulators. In this paper, we report a compact high-performance modulator based on the thin-film lithium niobate platform on a silicon substrate. The periodic capacitively loaded travelling-wave electrode is employed to achieve a large modulation bandwidth and a low drive voltage, which can support a driverless single-lane 100Gbaud operation. The folded modulation section design also helps to reduce the device length by almost two thirds. The fabricated device represents a large EO bandwidth of 45GHz with a half-wave voltage of 0.7V. The driverless transmission of a 100Gbaud 4-level pulse amplitude modulation signal is demonstrated with a power consumption of 4.49fj/bit and a bit-error rate below the KP4 forward-error correction threshold of 2.4×10-4.

12.
Opt Express ; 30(13): 22860-22870, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36224977

RESUMO

In this paper, a high-sensitivity distributed optical fiber salinity sensor based on frequency-scanning phase-sensitive optical time-domain reflectometry (φ-OTDR) and polyimide-coated single-mode fiber is proposed. Distributed salinity sensing over an 1100 m polyimide-coated fiber with a 1 m spatial resolution was demonstrated, and a sensitivity of 782.4 MHz/(mol/L) was achieved with the salinity changing from 0 mol/L to 1.61 mol/L. Then the measurement accuracies of frequency shift and salinity were evaluated theoretically and experimentally. Both theoretical and experimental results show that the measurement accuracy deteriorates as the pulse width decreases, resulting in a trade-off between the spatial resolution and measurement accuracy. The measurement uncertainty of salinity is 0.022 mol/L in the case of 30 cm spatial resolution. And when the spatial resolution is set to be 2 m, the measurement uncertainty of salinity decreases to 0.005 mol/L. The response time of the fiber to external salinity change has also been investigated, and it takes about 8 minutes for the fiber to reach a stable state. The proposed salinity sensor exhibits high sensitivity and long measurement range, which may be used for distributed marine environmental monitoring.

13.
Phys Rev Lett ; 129(14): 140401, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36240393

RESUMO

Quantum mechanics is commonly formulated in a complex, rather than real, Hilbert space. However, whether quantum theory really needs the participation of complex numbers has been debated ever since its birth. Recently, a Bell-like test in an entanglement-swapping scenario has been proposed to distinguish standard quantum mechanics from its real-valued analog. Previous experiments have conceptually demonstrated, yet not satisfied, the central requirement of independent state preparation and measurements and leave several loopholes. Here, we implement such a Bell-like test with two separated independent sources delivering entangled photons to three separated parties under strict locality conditions that are enforced by spacelike separation of the relevant events, rapid random setting generation, and fast measurement. With the fair-sampling assumption and closed loopholes of independent source, locality, and measurement independence simultaneously, we violate the constraints of real-valued quantum mechanics by 5.30 standard deviations. Our results disprove the real-valued quantum theory to describe nature and ensure the indispensable role of complex numbers in quantum mechanics.

14.
Opt Express ; 30(19): 33708-33720, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36242399

RESUMO

We demonstrate a flat broadband time-stretched swept source based on extra-cavity spectral shaping. By adjusting the polarization-dependent gain profile and driving current of the booster optical amplifier (BOA), extra-cavity spectral shaping is optimized to generate output with a 1-dB bandwidth of ∼100 nm, 3-dB bandwidth of ∼140 nm and output power of ∼21.4 mW. The short-term and long-term stabilities are characterized. The average cross correlation of 183,485 round trips is 0.9997 with a standard deviation of 2×10-5, indicating high single-shot spectral similarity and high coherence. The noise floor of relative spectral energy jitter is -141.7 dB/Hz, indicating a high short-term spectral energy stability. The proposed highly stable flat broadband time-stretched swept source is applied to an optical coherence tomography (OCT) system. The axial resolution is 10.8 µm. The proposed swept source can serve as excellent light sources in ultra-fast coherent detection systems for high precision sensing and imaging.

15.
Pharm Biol ; 60(1): 1865-1875, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36205544

RESUMO

CONTEXT: Sasanquasaponin (SQS) is a commonly used traditional Chinese medicine proved to have a wide range of pharmacological functions. OBJECTIVE: The objective of this study is to explore the effect and underlying mechanism of SQS in the treatment of prostate cancer (PC). MATERIALS AND METHODS: PC cell lines (22Rv1 and PC-3) were treated with SQS (0, 0.5, 1, 2, and 4 µM) for 12 or 24 h. The viability of cells was evaluated, while the mRNA and protein levels of epithelial to mesenchymal transition (EMT)-related genes in PC cell lines were measured (Groups: Control, TGF-ß1, TNF-α, TGF-ß1 + TNF-α, and TGF-ß1 + TNF-α + SQS). The migration and invasion abilities of PC cell lines were evaluated (Groups: Control, SQS). Finally, the antitumour effect of SQS (25, 50,100, and 200 mg/kg) in BALB/c nude mice (6 weeks, 18-20 g) was evaluated (Groups: Control, Vehicle, 25, 50,100, and 200 mg/kg SQS). The study duration was 1 month. RESULTS: SQS inhibited the viability and the number of colonies of 22Rv1 or PC-3 cells. The IC50 of SQS of 12 and 24 h in these two cells was 3.25, 1.82, 4.76, and 4.70 µM, respectively. SQS inhibited the adhesion, migration, and invasion of PC cells. It also inhibited the expression of EMT-related markers of PC cells. The PI3K/Akt/mTOR and Smad2/3 signalling pathways were activated in the process of EMT, and SQS could significantly reduce the activation of the PI3K/Akt/mTOR and Smad2/3 pathways. Finally, SQS inhibited the growth of xenograft tumours in vivo. CONCLUSIONS: SQS inhibited EMT in PC by regulating the PI3K/Akt/mTOR and Smad pathways.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias da Próstata , Animais , Linhagem Celular Tumoral , Movimento Celular , Humanos , Masculino , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro , Saponinas , Proteínas Smad/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
16.
Opt Lett ; 47(19): 5144-5147, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181207

RESUMO

In C-band intensity modulation and direct detection (IM/DD) systems, the frequency-dependent power fading induced by chromatic dispersion (CD) and square-law detection limits the transmission capacity and distance, especially for beyond 100-Gb/s transmissions over a 100-km dispersion-uncompensated link. To reach this goal, we propose a scheme of nonlinear pre-distortion, novel, to the best of our knowledge, combined pulse shaping, and post nonlinear equalization for four-level pulse amplitude modulation (PAM-4)-based IM/DD systems. At the transmitter, the nonlinear pre-distortion is used to generate unequally spaced PAM-4 symbols for pre-compensating the nonlinearities. While the novel pulse shaping, simply shaped by the linear combination of two inter-symbol interference (ISI)-free pulses, alters the frequency-domain power distribution of the PAM-4 signal and results in performance improvement. At the receiver, low-complexity post nonlinear equalization using an absolute-term based nonlinear equalizer with weight sharing (AT-NLE-WS) is performed to eliminate CD-induced power fading and residual nonlinear impairments. With the cooperation of these techniques, record 120-Gb/s PAM-4 signals are successfully transmitted over a 100-km standard single-mode fiber (SSMF) with the measured bit error ratio (BER) below 3.8 × 10-3, achieving >9% improvement of system capacity in comparison with the conventional pulse shaping schemes.

17.
Opt Express ; 30(20): 36343-36357, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258564

RESUMO

To cope with the nonlinear distortions and the chromatic dispersion (CD) induced power fading in double-side band (DSB) intensity modulation and direct detection (IM/DD) transmission systems, high-performance Volterra nonlinear equalizers (VNLEs) including Volterra feed-forward equalizer (VFFE) and Volterra decision-feedback equalizer (VDFE) are widely applied. However, the conventional VNLEs have high computational complexity, especially for longer memory lengths. In this paper, based on sparse and weight-sharing strategies for significant kernel reduction, we propose four low-complexity NLEs including a sparse diagonally pruned VDFE (S-DP-VDFE), a sparse diagonally pruned absolute-term DFE (S-DP-ATDFE), a weight-sharing DP-VDFE (WS-DP-VDFE), and a weight-sharing DP-ATDFE (WS-DP-ATDFE), and present a comprehensive comparison among them in terms of computational complexity and bit error ratio (BER) performance in a C-band 100-Gbit/s PAM-4 transmission system over 60-km standard single-mode fiber (SSMF). The experimental results show that the proposed S-DP-VDFE and WS-DP-VDFE not only exhibit comparable performance with the conventional DP-VDFE but also reduce the complexity by 54.5% and 45.9%, respectively. While the proposed S-DP-ATDFE and WS-DP-ATDFE yield lower complexity at the expense of a slight performance degradation. Compared with the proposed S-DP-VDFE, S-DP-ATDFE, and WS-DP-VDFE, the proposed WS-DP-ATDFE with the lowest number of real-valued multiplications of 45 achieves up to 90.9%, 81.6%, and 95.8% complexity reduction, respectively, at the 7% hard-decision forward error correction (HD-FEC) BER limit of 3.8 × 10-3. The proposed low-complexity WS-DP-ATDFE shows great potential in low-cost and high-performance IM/DD optical transmission systems.

18.
Molecules ; 27(19)2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36235054

RESUMO

Carbon dots (CDs) have excellent optical properties, low toxicity and easy preparation, which have led to them being widely used in biomedicine, sensing and optical devices. However, although great progress has been made in the preparation of CDs, the detailed exploration of their photoluminescence (PL) mechanism is still under debate due to their complex structures and surface functionalities. Here, we proposed a single change in the pH of the synthesis condition, which had no effect on the CDs intrinsic core states and avoided the mutual influence of multiple PL origins. The m-phenylenediamine (m-PD) served as a carbon source, whose protonation degree determined the surface state of the resulting CDs and the accompanying fluorescence characteristics. The as-obtained CDs materials can be applied in the chemical sensor and anti-counterfeiting fields in a targeted manner. Therefore, our work not only contributes to the explanation of the CDs PL mechanism, but also obtains a series of CDs materials with controllable PL properties.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Pontos Quânticos/química
19.
Mol Cell ; 82(20): 3901-3918.e7, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36206767

RESUMO

How cancer-associated chromatin abnormalities shape tumor-immune interaction remains incompletely understood. Recent studies have linked DNA hypomethylation and de-repression of retrotransposons to anti-tumor immunity through the induction of interferon response. Here, we report that inactivation of the histone H3K36 methyltransferase NSD1, which is frequently found in squamous cell carcinomas (SCCs) and induces DNA hypomethylation, unexpectedly results in diminished tumor immune infiltration. In syngeneic and genetically engineered mouse models of head and neck SCCs, NSD1-deficient tumors exhibit immune exclusion and reduced interferon response despite high retrotransposon expression. Mechanistically, NSD1 loss results in silencing of innate immunity genes, including the type III interferon receptor IFNLR1, through depletion of H3K36 di-methylation (H3K36me2) and gain of H3K27 tri-methylation (H3K27me3). Inhibition of EZH2 restores immune infiltration and impairs the growth of Nsd1-mutant tumors. Thus, our work uncovers a druggable chromatin cross talk that regulates the viral mimicry response and enables immune evasion of DNA hypomethylated tumors.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Histona Metiltransferases , Evasão Tumoral , Animais , Camundongos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Cromatina , Metilação de DNA , Neoplasias de Cabeça e Pescoço/genética , Histona Metiltransferases/genética , Histona Metiltransferases/metabolismo , Histonas/genética , Histonas/metabolismo , Interferons/genética , Proteínas Nucleares/metabolismo , Receptores de Interferon/genética , Retroelementos , Evasão Tumoral/genética
20.
Nature ; 610(7933): 661-666, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198794

RESUMO

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

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