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1.
Nano Lett ; 24(7): 2299-2307, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38334593

RESUMO

Organic-inorganic hybrid perovskites have attracted tremendous attention owing to their fascinating optoelectronic properties. However, their poor air stability seriously hinders practical applications, which becomes more serious with thickness down to the nanoscale. Here we report a one-step vapor phase growth of HC(NH2)2PbBr3 (FAPbBr3) single-crystalline nanosheets of tunable size up to 50 µm and thickness down to 20 nm. The FAPbBr3 nanosheets demonstrate high stability for over months of exposure to air with no degradation in surface roughness and photoluminescence efficiency. Besides, the FAPbBr3 photodetectors exhibit superior overall performance as compared to previous devices based on nonlayered perovskite nanosheets, such as an ultralow dark current of 24 pA, an ultrahigh responsivity of 1033 A/W, an external quantum efficiency over 3000%, a rapid response time around 25 ms, and a high on/off ratio of 104. This work provides a strategy to tackle the challenges of hybrid perovskites toward integrated optoelectronics with requirements of nanoscale thickness, high stability, and excellent performance.

2.
J Proteome Res ; 23(6): 2195-2205, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38661673

RESUMO

The programmed death-ligand 1 (PD-L1) is a key mediator of immunosuppression in the tumor microenvironment. The expression of PD-L1 in cancer cells is useful for the clinical determination of an immune checkpoint blockade (ICB). However, the regulatory mechanism of the PD-L1 abundance remains incompletely understood. Here, we integrated the proteomics of 52 patients with solid tumors and examined immune cell infiltration to reveal PD-L1-related regulatory modules. Wiskott-Aldrich syndrome protein (WASP) was identified as a potential regulator of PD-L1 transcription. In two independent cohorts containing 164 cancer patients, WASP expression was significantly associated with PD-L1. High WASP expression contributed to immunosuppressive cell composition, including cells positive for immune checkpoints (PD1, CTLA4, TIGIT, and TIM3), FoxP3+ Treg cells, and CD163+ tumor-associated macrophages. Overexpression of WASP increased, whereas knockdown of WASP decreased the protein level of PD-L1 in cancer cells without alteration of PD-L1 protein stability. The WASP-mediated cell migration and invasion were markedly attenuated by the silence of PD-L1. Collectively, our data suggest that WASP is a potential regulator of PD-L1 and the WASP/PD-L1 axis is responsible for cell migration and an immunosuppressive microenvironment.


Assuntos
Antígeno B7-H1 , Neoplasias , Proteômica , Microambiente Tumoral , Proteína da Síndrome de Wiskott-Aldrich , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Proteômica/métodos , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Neoplasias/metabolismo , Neoplasias/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
3.
J Thromb Thrombolysis ; 57(1): 67-81, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37940761

RESUMO

BACKGROUND: Accumulating evidence links the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement to venous thromboembolism (VTE) in non-small cell lung cancer (NSCLC) patients. However, the corresponding mechanisms remain unclear. METHOD: High-throughput sequencing analysis of H3122 human ALK-positive NSCLC cells treated with ALK inhibitor/ dimethyl sulfoxide (DMSO) was performed to identify coagulation-associated differential genes between EML4-ALK fusion protein inhibited cells and control cells. Sequentially, we confirmed its expression in NSCLC patients' tissues and in the plasma of a subcutaneous xenograft mouse model. An inferior vena cava (IVC) ligation model was used to assess clot formation potential. Additionally, pathways involved in tissue factor (TF) regulation were explored in ALK-positive cell lines H3122 and H2228. Statistical significance was determined by Student t-test and one-way ANOVA using SPSS. RESULTS: Sequencing analysis identified a significant downregulation of TF after inhibiting EML4-ALK fusion protein activity in H3122 cells. In clinical NSCLC cases, TF expression was increased especially in ALK-positive NSCLC tissues. Meanwhile, H3122 and H2228 with high TF expression exhibited shorter plasma clotting time and higher TF activity versus ALK-negative H1299 and A549 in cell culture supernatant. Mice bearing H2228 tumor showed a higher concentration of tumor-derived TF and TF activity in plasma and the highest adjusted IVC clot weights. Limiting EML4-ALK protein phosphorylation downregulated extracellular regulated protein kinases 1/2 (ERK1/2)-activating the protein-1(AP-1) signaling pathway and thus attenuated TF expression. CONCLUSION: EML4-ALK fusion protein may enhance venous thrombogenicity by regulating coagulation factor TF expression. There was potential involvement of the pERK1/2-AP-1 pathway in this process.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/uso terapêutico , Tromboplastina/genética , Fator de Transcrição AP-1/uso terapêutico , Proliferação de Células , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/análise , Proteínas de Fusão Oncogênica/metabolismo
4.
Gerontology ; : 1-21, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857587

RESUMO

INTRODUCTION: Anxiety and depression are prevalent among older adults, and digital interactive interventions have shown promise in promoting their mental well-being. However, limited research has explored the effects of different types of digital interactive interventions across various devices on anxiety and depression in older adults with different health conditions. METHODS: A systematic literature review and meta-analysis were conducted using seven selected databases to identify relevant studies up to July 19, 2023. Two reviewers independently conducted study selection, data extraction, and quality appraisals. The risk of bias in the included studies was assessed using the Cochrane risk-of-bias tool. For the meta-analysis, the effect size was calculated as the standardized mean difference (SMD) using a random-effects model. RESULTS: A total of 20 randomized control trails involving 1,309 older adults fulfilled inclusion criteria. The meta-analysis results demonstrates that the digital interactive intervention technologies had a significance on depression (SMD = -0.656 s, 95% confidence interval [CI] = -0.992 to -0.380, p < 0.001) and anxiety (SMD = -0.381 s, 95% CI = -0.517 to -0.245, p < 0.001). Physical interactive interventions demonstrated a significant effect on depression and anxiety (SMD = -0.711 s, 95% CI = -1.102 to -0.319, p < 0.001) and (SMD = -0.573 s, 95% CI = -0.910 to -0.236, p = 0.001). Similarly, immersive interactive interventions also showed a significant effect on depression and anxiety (SMD = -0.699 s, 95% CI = -1.026 to -0.373, p < 0.001) and (SMD = -0.343 s, 95% CI = -0.493 to -0.194, p < 0.001). Additionally, in the internal medicine group, significant intervention effects were observed for depression (SMD = -0.388, 95% CI = -0.630 to -0.145, p = 0.002) and anxiety (SMD = -0.325, 95% CI = -0.481 to -0.169, p < 0.001). Similarly, in the neurocognitive disorders group, significant intervention effects were found for depression (SMD = -0.702, 95% CI = -0.991 to -0.413, p < 0.001) and anxiety (SMD = -0.790, 95% CI = -1.237 to -0.342, p = 0.001). CONCLUSION: The results indicated that various digital interactive devices, including physical and immersive interactive devices, have a positive impact on depression and anxiety among older adults. However, mobile games were not effective in addressing depression. Digital interactive technologies did not significantly influence anxiety intervention, except for elderly individuals undergoing surgical procedures. Nevertheless, these interventions effectively addressed depression and anxiety in older individuals with neurocognitive disorders, internal medical issues, and those without health issues.

5.
Alzheimers Dement ; 20(4): 2698-2706, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38400532

RESUMO

INTRODUCTION: Increasing evidence suggests that amyloid reduction could serve as a plausible surrogate endpoint for clinical and cognitive efficacy. The double-blind phase 3 DIAN-TU-001 trial tested clinical and cognitive declines with increasing doses of solanezumab or gantenerumab. METHODS: We used latent class (LC) analysis on data from the Dominantly Inherited Alzheimer Network Trials Unit 001 trial to test amyloid positron emission tomography (PET) reduction as a potential surrogate biomarker. RESULTS: LC analysis categorized participants into three classes: amyloid no change, amyloid reduction, and amyloid growth, based on longitudinal amyloid Pittsburgh compound B PET standardized uptake value ratio data. The amyloid-no-change class was at an earlier disease stage for amyloid amounts and dementia. Despite similar baseline characteristics, the amyloid-reduction class exhibited reductions in the annual decline rates compared to the amyloid-growth class across multiple biomarker, clinical, and cognitive outcomes. DISCUSSION: LC analysis indicates that amyloid reduction is associated with improved clinical outcomes and supports its use as a surrogate biomarker in clinical trials. HIGHLIGHTS: We used latent class (LC) analysis to test amyloid reduction as a surrogate biomarker. Despite similar baseline characteristics, the amyloid-reduction class exhibited remarkably better outcomes compared to the amyloid-growth class across multiple measures. LC analysis proves valuable in testing amyloid reduction as a surrogate biomarker in clinical trials lacking significant treatment effects.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Amiloide , Peptídeos beta-Amiloides , Proteínas Amiloidogênicas , Biomarcadores , Método Duplo-Cego , Análise de Classes Latentes , Tomografia por Emissão de Pósitrons/métodos
6.
Molecules ; 29(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38474473

RESUMO

Transition metal nitride negative electrode materials with a high capacity and electronic conduction are still troubled by the large volume change in the discharging procedure and the low lithium ion diffusion rate. Synthesizing the composite material of F-doped Fe3N and an N-doped porous carbon framework will overcome the foregoing troubles and effectuate a preeminent electrochemical performance. In this study, we created a simple route to obtain the composite of F-doped Fe3N nanoellipsoids and a 3D N-doped porous carbon framework under non-ammonia atmosphere conditions. Integrating the F-doped Fe3N nanoellipsoids with an N-doped porous carbon framework can immensely repress the problem of volume expansion but also substantially elevate the lithium ion diffusion rate. When utilized as a negative electrode for lithium-ion batteries, this composite bespeaks a stellar operational life and rate capability, releasing a tempting capacity of 574 mAh g-1 after 550 cycles at 1.0 A g-1. The results of this study will profoundly promote the evolution and application of transition metal nitrides in batteries.

7.
J Neurochem ; 166(4): 678-691, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37439370

RESUMO

Peripheral nerves have limited regeneration ability following nerve injury. Applying growth factors with neurotrophic roles is beneficial for accelerating peripheral nerve regeneration. Here we show that after rat sciatic nerve injury, growth factor amphiregulin (AREG) is upregulated in Schwann cells of sciatic nerves. Elevated AREG stimulates the proliferation and migration of Schwann cells by activating ERK1/2 cascade. Schwann cell-secreted AREG further facilitates the outgrowth of neurites and the elongation of injured axons. Administration of AREG to injured sciatic nerves stimulates the proliferation of Schwann cells to replace lost cell population, encourages the migration of Schwann cells to form cell cords, and facilitates the regrowth of axons. Overall, our results identify AREG as an important neurotrophic factor and thus provide a promising therapeutic avenue towards peripheral nerve injury.


Assuntos
Axônios , Traumatismos dos Nervos Periféricos , Ratos , Animais , Anfirregulina/farmacologia , Anfirregulina/metabolismo , Axônios/metabolismo , Células de Schwann/metabolismo , Regeneração Nervosa/fisiologia , Nervo Isquiático/lesões , Traumatismos dos Nervos Periféricos/metabolismo , Proliferação de Células
8.
Biochem Biophys Res Commun ; 650: 62-72, 2023 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-36773341

RESUMO

Silk methacrylate (SilMA) has been studied extensively due to its ability to modify Silk fibroin (SF) by increasing the water solubility and enhancing the mechanical properties of SF hydrogels. However, SilMA hydrogels are generally soft with weak mechanical properties. In order to enhance the mechanical properties of hydrogel scaffolds, we used liquid nitrogen to modify SilMA to obtain a novel N2-SilMA/gelatin-methacryloyl (GelMA) composite hydrogel. N2-SilMA was successfully detected by Fourier transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance. Scanning electron microscope showed that the composite hydrogel still had certain arrangement characteristics of SF and dense pores which met the necessary conditions for the cell scaffold. The mechanical tests showed that the mechanical properties of SilMA were greatly enhanced after modification at ultra-low temperature. We evaluated its cytocompatibility and biocompatibility, and the results showed that the composite scaffold promoted the growth of cells. Different types of composite hydrogels were injected into ICR mice and the results showed a stable scaffold structure in vivo, suggesting their ability to promote angiogenesis. In conclusion, the N2-SilMA/GelMA composite hydrogel had better mechanical properties, excellent cytocompatibility, and biological properties compared to the other groups.


Assuntos
Fibroínas , Engenharia Tecidual , Animais , Camundongos , Engenharia Tecidual/métodos , Seda/química , Gelatina/química , Hidrogéis/química , Estudos de Viabilidade , Camundongos Endogâmicos ICR , Alicerces Teciduais/química , Fibroínas/química , Metacrilatos
9.
Small ; 19(43): e2301573, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37365697

RESUMO

2D metal halides have attracted increasing research attention in recent years; however, it is still challenging to synthesize them via liquid-phase methods. Here it is demonstrated that a droplet method is simple and efficient for the synthesis of multiclass 2D metal halides, including trivalent (BiI3 , SbI3 ), divalent (SnI2 , GeI2 ), and monovalent (CuI) ones. In particular, 2D SbI3 is first experimentally achieved, of which the thinnest thickness is ≈6 nm. The nucleation and growth of these metal halide nanosheets are mainly determined by the supersaturation of precursor solutions that are dynamically varying during the solution evaporation. After solution drying, the nanosheets can fall on the surface of many different substrates, which further enables the feasible fabrication of related heterostructures and devices. With SbI3 /WSe2 being a good demonstration, the photoluminescence intensity and photo responsivity of WSe2 is obviously enhanced after interfacing with SbI3 . The work opens a new pathway for 2D metal halides toward widespread investigation and applications.

10.
Mol Carcinog ; 62(6): 771-785, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36988339

RESUMO

Replication factor C 5 (RFC5) is involved in a variety of biological functions of cancer. However, the expression pattern of RFC5 and the underlying mechanisms in colorectal cancer (CRC) remain elusive. Here, we show that RFC5 is significantly upregulated in CRC tissues and cells. Patients with CRC and increased RFC5 levels have an unfavorable prognosis. RFC5 can promote the proliferation, migration, and invasion of CRC cells and inhibit the apoptosis of CRC cells. Additionally, upstream of RFC5, we constructed the competing endogenous RNA network and confirmed that RFC5 in this network was inhibited by miR-3614-5p by directly targeting its 3'-untranslated regions. We verified that circ_0038985, which is positively correlated with RFC5, directly targeted miR-3614-5p. Overexpression of circ_0038985 promoted CRC cell migration and invasion, and these effects were partially reversed by the reintroduction of miR-3614-5p. Moreover, we found that RFC5 may promote the vascular endothelial growth factor A (VEGFa)/vascular endothelial growth factor receptor 2 (VEGFR2)/extracellular signal-regulated protein kinase (ERK) pathway. The knockdown of RFC5 reduced CRC tumorigenesis in vivo. Collectively, these data demonstrate that the circ_0038985/miR-3614-5p/RFC5 axis plays a critical role in the progression of CRC, and RFC5 may promote CRC progression by affecting the VEGFa/VEGFR2/ERK pathway.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína de Replicação C/genética , Proteína de Replicação C/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Oncogenes
11.
J Med Virol ; 95(1): e28310, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36377393

RESUMO

Cellular infections by DNA viruses trigger innate immune responses mediated by DNA sensors. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) signaling pathway has been identified as a DNA-sensing pathway that activates interferons in response to viral infection and, thus, mediates host defense against viruses. Previous studies have identified oncogenes E7 and E1A of the DNA tumor viruses, human papillomavirus 18 (HPV18) and adenovirus, respectively, as inhibitors of the cGAS-STING pathway. However, the function of STING in infected cells and the mechanism by which HPV18 E7 antagonizes STING-induced Interferon beta production remain unknown. We report that HPV18 E7 selectively antagonizes STING-triggered nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation but not IRF3 activation. HPV18 E7 binds to STING in a region critical for NF-κB activation and blocks the nuclear accumulation of p65. Moreover, E7 inhibition of STING-triggered NF-κB activation is related to HPV pathogenicity but not E7-Rb binding. HPV18 E7, severe acute respiratory syndrome coronavirus-2 open reading frame 3a, human immunodeficiency virus-2 viral protein X, and Kaposi's sarcoma-associated herpesvirus KSHV viral interferon regulatory factor 1 selectively inhibited STING-triggered NF-κB or IRF3 activation, suggesting a convergent evolution among these viruses toward antagonizing host innate immunity. Collectively, selective suppression of the cGAS-STING pathway by viral proteins is likely to be a key pathogenic determinant, making it a promising target for treating oncogenic virus-induced tumor diseases.


Assuntos
COVID-19 , NF-kappa B , Humanos , NF-kappa B/metabolismo , Interferon beta/genética , Papillomavirus Humano 18/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Imunidade Inata , DNA , Vírus de DNA/genética , Vírus de DNA/metabolismo , Proteínas Oncogênicas
12.
Opt Express ; 31(13): 22144-22156, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381295

RESUMO

Aiming at the problems of narrow working bandwidth, low efficiency, and complex structure of existing terahertz chiral absorption, we propose a chiral metamirror composed of C-shaped metal split ring and L-shaped vanadium dioxide (VO2). This chiral metamirror is composed of three layers of structure, a gold substrate at the bottom, the first polyethylene cyclic olefin copolymer (Topas) dielectric layer and VO2-metal hybrid structure as the top. Our theoretical results led us to show that this chiral metamirror has a circular dichroism (CD) value greater than 0.9 at 5.70 to 8.55 THz and has a maximum value of 0.942 at f = 7.18 THz. In addition, by adjusting the conductivity of VO2, the CD value can be continuously adjustable from 0 to 0.942, which means that the proposed chiral metamirror supports the free switching of the CD response between the on and off states, and the CD modulation depth exceeds 0.99 in the range of 3 to 10 THz. Moreover, we discuss the influence of structural parameters and the change of incident angle on the performance of the metamirror. Finally, we believe that the proposed chiral metamirror has important reference value in the terahertz range for constructing chiral light detectors, CD metamirrors, switchable chiral absorbers and spin-related systems. This work will provide a new idea for improving the terahertz chiral metamirror operating bandwidth and promote the development of terahertz broadband tunable chiral optical devices.

13.
Opt Lett ; 48(19): 5153-5156, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773408

RESUMO

The deep application of chiral metasurfaces requires higher flexibility. Herein, we propose a multidimensional tunable chiral graphene metasurface, which uses coherent control to obtain more than 0.8 circular conversion dichroism (CCD) at 2.4 THz as a transmission structure. Its operating frequency can be changed in the 1.3-2.4 THz range, while the amplitude has almost perfect modulation depth in the range of 0-0.8. The mechanism of differential absorption was analyzed through numerical simulation. The device designed is easy to obtain reverse CCD, which is used for unit layout and proves its advantages in near-field imaging. Our work has broadened the path for the development of chiral metasurfaces towards higher degrees of freedom.

14.
Eur J Nucl Med Mol Imaging ; 50(9): 2669-2682, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37017737

RESUMO

PURPOSE: Pittsburgh Compound-B (11C-PiB) and 18F-florbetapir are amyloid-ß (Aß) positron emission tomography (PET) radiotracers that have been used as endpoints in Alzheimer's disease (AD) clinical trials to evaluate the efficacy of anti-Aß monoclonal antibodies. However, comparing drug effects between and within trials may become complicated if different Aß radiotracers were used. To study the consequences of using different Aß radiotracers to measure Aß clearance, we performed a head-to-head comparison of 11C-PiB and 18F-florbetapir in a Phase 2/3 clinical trial of anti-Aß monoclonal antibodies. METHODS: Sixty-six mutation-positive participants enrolled in the gantenerumab and placebo arms of the first Dominantly Inherited Alzheimer Network Trials Unit clinical trial (DIAN-TU-001) underwent both 11C-PiB and 18F-florbetapir PET imaging at baseline and during at least one follow-up visit. For each PET scan, regional standardized uptake value ratios (SUVRs), regional Centiloids, a global cortical SUVR, and a global cortical Centiloid value were calculated. Longitudinal changes in SUVRs and Centiloids were estimated using linear mixed models. Differences in longitudinal change between PET radiotracers and between drug arms were estimated using paired and Welch two sample t-tests, respectively. Simulated clinical trials were conducted to evaluate the consequences of some research sites using 11C-PiB while other sites use 18F-florbetapir for Aß PET imaging. RESULTS: In the placebo arm, the absolute rate of longitudinal change measured by global cortical 11C-PiB SUVRs did not differ from that of global cortical 18F-florbetapir SUVRs. In the gantenerumab arm, global cortical 11C-PiB SUVRs decreased more rapidly than global cortical 18F-florbetapir SUVRs. Drug effects were statistically significant across both Aß radiotracers. In contrast, the rates of longitudinal change measured in global cortical Centiloids did not differ between Aß radiotracers in either the placebo or gantenerumab arms, and drug effects remained statistically significant. Regional analyses largely recapitulated these global cortical analyses. Across simulated clinical trials, type I error was higher in trials where both Aß radiotracers were used versus trials where only one Aß radiotracer was used. Power was lower in trials where 18F-florbetapir was primarily used versus trials where 11C-PiB was primarily used. CONCLUSION: Gantenerumab treatment induces longitudinal changes in Aß PET, and the absolute rates of these longitudinal changes differ significantly between Aß radiotracers. These differences were not seen in the placebo arm, suggesting that Aß-clearing treatments may pose unique challenges when attempting to compare longitudinal results across different Aß radiotracers. Our results suggest converting Aß PET SUVR measurements to Centiloids (both globally and regionally) can harmonize these differences without losing sensitivity to drug effects. Nonetheless, until consensus is achieved on how to harmonize drug effects across radiotracers, and since using multiple radiotracers in the same trial may increase type I error, multisite studies should consider potential variability due to different radiotracers when interpreting Aß PET biomarker data and, if feasible, use a single radiotracer for the best results. TRIAL REGISTRATION: ClinicalTrials.gov NCT01760005. Registered 31 December 2012. Retrospectively registered.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Compostos de Anilina , Etilenoglicóis , Encéfalo/metabolismo
15.
Langmuir ; 39(10): 3792-3799, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36853231

RESUMO

Low-dimension perovskite materials have attracted wide attention due to their excellent optical properties and stability. Herein, Sb3+-doped Cs2ZrCl6 crystals are synthesized by a coprecipitation method in which Sb3+ ions partially replace Zr4+ ions. The Cs2ZrCl6:xSb3+ powder shows blue and orange-red emissions under a 254 and 365 nm light, respectively, due to the [ZrCl6]2- octahedron and [SbCl6]3- octahedron. The photoluminescence quantum yield (PLQY) of Cs2ZrCl6:xSb3+ (x = 0.1) crystals is up to 52.5%. According to experimental and computational results, the emission mechanism of the Cs2ZrCl6:xSb3+ crystals is proposed. On the one hand, a wide blue emission with a large Stokes shift is caused by the self-trapping excitons of [ZrCl6]2- octahedra under a 260 nm excitation. On the other hand, the luminescence mechanism of [SbCl6]3- octahedron is divided into two parts: 1P1 → 1S0 (490 nm) and 3P1 → 1S0 (625 nm). The broad-band emission, high PLQY, and excellent stability endow the Cs2ZrCl6:xSb3+ powders with the potential for the fabrication of white light-emitting diodes (WLEDs). A WLED device is fabricated using a commercial 310 nm NUV chip, which shows a high color rendering index of 89.7 and a correlated color temperature of 5333 K. In addition, the synthesized Cs2ZrCl6:xSb3+ crystals can be also successfully used for information encryption. Our work will provide a deep understanding of the photophysical properties of Sb3+-doped perovskites and facilitate the development of Cs2ZrCl6:xSb3+ crystals in encrypting multilevel optical codes and WLEDs.

16.
Appl Opt ; 62(23): 6205-6211, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707089

RESUMO

In this paper, a nested micro-ring refractive index sensor based on a subwavelength grating waveguide and the Vernier effect is proposed. In this scheme, the nested micro-ring structure is combined with a subwavelength grating structure to enhance the contact area between the optical field and the analyte, and the wavelength offset is doubled through the Vernier effect. The proposed sensor can effectively increase sensing sensitivity, taking into account the improvement of the free spectral range. This structure enables the device to reach a sensitivity of 8030 nm/RIU near 1550 nm wavelength in a deionized water environment, with a detection limit of 5.659×10-5 RIU and free spectral range of 41.956 nm. The device suggested in this study has a greater reduced footprint than the conventional micro-ring resonant sensor, measuring just 35µm×25µm. Due to its high integration, high sensitivity, and large free spectral range compared to conventional micro-ring resonant sensors, such structures are of great value in biosensing and environmental monitoring.

17.
Appl Opt ; 62(28): 7346-7353, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855501

RESUMO

Electro-optic modulators are essential devices on silicon photonic chips in modern optical communication networks. This paper presents a compact, low-loss electro-optic modulator. The modulation efficiency is greatly improved by embedding the lower half of the slot waveguide into the buried oxide layer and inserting graphene at the junction. The interaction of graphene with an optical field in a waveguide is studied using the finite element method. The functions of phase modulation and absorption modulation are realized by changing the gate voltage to change the chemical potential of graphene. The semi-embedded slot waveguide optical modulator has a length of 50 µm. After simulation verification, it can be used as an electro-absorption modulator and can achieve a modulation depth of 26.38 dB and an insertion loss of 0.60 dB. When used as an electro-refractive modulator, it can be realized with a linear change of phase from zero to π; the total insertion loss is only 0.59 dB. The modulator has a modulation bandwidth of 79.6 GHz, and the energy consumption as electro-absorption and electro-refraction modulation are 0.51 and 1.92 pj/bit, respectively. Compared with common electro-optic modulators, the electro-optic modulator designed in this paper has a higher modulation effect and also takes into account the advantages of low insertion loss and low energy consumption. This research is helpful for the design of higher-performance optical communication network devices.

18.
Metab Brain Dis ; 38(7): 2369-2381, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37256467

RESUMO

Neuropsychiatric disorders have a high incidence worldwide. Kinesins, a family of microtubule-based molecular motor proteins, play essential roles in intracellular and axonal transport. Variants of kinesins have been found to be related to many diseases, including neurodevelopmental/neurodegenerative disorders. Kinesin-12 (also known as Kif15) was previously found to affect the frequency of both directional microtubule transports. However, whether Kif15 deficiency impacts mood in mice is yet to be investigated. In this study, we used the CRISPR/Cas9 method to obtain Kif15-/- mice. In behavioral tests, Kif15-/- female mice exhibited prominent depressive characteristics. Further studies showed that the expression of BDNF was significantly decreased in the frontal cortex, corpus callosum, and hippocampus of Kif15-/- mice, along with the upregulation of Interleukin-6 and Interleukin-1ß in the corpus callosum. In addition, the expression patterns of AnkG were notably changed in the developing brain of Kif15-/- mice. Based on our previous studies, we suggested that this appearance of altered AnkG was due to the maladjustment of the microtubule patterns induced by Kif15 deficiency. The distribution of PSD95 in neurites notably decreased after cultured neurons treated with the Kif15 inhibitor, but total PSD95 protein level was not impacted, which revealed that Kif15 may contribute to PSD95 transportation. This study suggested that Kif15 may serve as a potential target for future depression studies.


Assuntos
Depressão , Cinesinas , Animais , Feminino , Camundongos , Depressão/genética , Cinesinas/genética , Cinesinas/metabolismo , Microtúbulos/metabolismo , Neurônios/metabolismo
19.
Sensors (Basel) ; 23(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37430682

RESUMO

In this study, a new temperature sensor with high sensitivity was achieved by four-layer Ge and B co-doped long-period fiber grating (LPFG) based on the mode coupling principle. By analyzing the mode conversion, the influence of the surrounding refractive index (SRI), the thickness and the refractive index of the film on the sensitivity of the sensor is studied. When 10 nm-thick titanium dioxide (TiO2) film is coated on the surface of the bare LPFG, the refractive index sensitivity of the sensor can be initially improved. Packaging PC452 UV-curable adhesive with a high-thermoluminescence coefficient for temperature sensitization can realize high-sensitivity temperature sensing and meet the requirements of ocean temperature detection. Finally, the effects of salt and protein attachment on the sensitivity are analyzed, which provides a reference for the subsequent application. The sensitivity of 3.8 nm/°C in the range of 5-30 °C was achieved for this new sensor, and the resolution is about 0.00026 °C, which is over 20 times higher than ordinary temperature sensors. This new sensor meets the accuracy and range of general ocean temperature measurements and could be used in various marine monitoring and environmental protection applications.

20.
J Environ Manage ; 344: 118340, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37336018

RESUMO

Co-existence of antibiotics (ABX) in soil may expand the environmental harm of pesticide pollution. Our study investigated the combined effects of five antibiotics chlortetracycline (CTC), oxytetracycline (OTC), tetracycline (TC), sulfamethoxazole (SMX), enrofloxacin (ENR) on enantioselective fate of zoxamide (ZXM) and soil health. The results showed that S-(+)-ZXM preferentially dissipated in soil. ABX prolonged dissipation half-life and reduced enantioselectivity of ZXM. Soil was detected to be more acidic after long-term treatment of ZXM and ABX. Lowest soil available N, P, K were found in ZXM + SMX, ZXM + OTC and ZXM + SMX groups at 80 days, respectively. ABX had demonstrated effective promotion of catalase (S-CAT), urease (S-UE) and negative impact on dehydrogenase (S-DHA), sucrase (S-SC) activities. Bacteria Lysobacter, Sphingomonas and fungus Mortierella were identified as the most dominant genera, which possessed as potential microbial resources for removal of composite pollution from ZXM and ABX. SMX and TC, SMX, ENR, respectively, contributed to the alteration of bacteria and fungi community abundance. Soil acidity, available N and enzyme activity showed stronger correlations with bacteria and fungi compared to other environmental factors. Our findings highlighted the interactions between ZXM and ABX from the perspective of soil microenvironment changes. Moreover, a theoretical basis for the mechanism was actively provided.


Assuntos
Oxitetraciclina , Poluentes do Solo , Antibacterianos/farmacologia , Solo , Estereoisomerismo , Oxitetraciclina/análise , Tetraciclina , Sulfametoxazol , Bactérias , Poluentes do Solo/análise
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