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1.
Nature ; 591(7850): 385-390, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33731947

RESUMO

Two-dimensional (2D) materials1,2 and the associated van der Waals (vdW) heterostructures3-7 have provided great flexibility for integrating distinct atomic layers beyond the traditional limits of lattice-matching requirements, through layer-by-layer mechanical restacking or sequential synthesis. However, the 2D vdW heterostructures explored so far have been usually limited to relatively simple heterostructures with a small number of blocks8-18. The preparation of high-order vdW superlattices with larger number of alternating units is exponentially more difficult, owing to the limited yield and material damage associated with each sequential restacking or synthesis step8-29. Here we report a straightforward approach to realizing high-order vdW superlattices by rolling up vdW heterostructures. We show that a capillary-force-driven rolling-up process can be used to delaminate synthetic SnS2/WSe2 vdW heterostructures from the growth substrate and produce SnS2/WSe2 roll-ups with alternating monolayers of WSe2 and SnS2, thus forming high-order SnS2/WSe2 vdW superlattices. The formation of these superlattices modulates the electronic band structure and the dimensionality, resulting in a transition of the transport characteristics from semiconducting to metallic, from 2D to one-dimensional (1D), with an angle-dependent linear magnetoresistance. This strategy can be extended to create diverse 2D/2D vdW superlattices, more complex 2D/2D/2D vdW superlattices, and beyond-2D materials, including three-dimensional (3D) thin-film materials and 1D nanowires, to generate mixed-dimensional vdW superlattices, such as 3D/2D, 3D/2D/2D, 1D/2D and 1D/3D/2D vdW superlattices. This study demonstrates a general approach to producing high-order vdW superlattices with widely variable material compositions, dimensions, chirality and topology, and defines a rich material platform for both fundamental studies and technological applications.

2.
Nature ; 579(7799): 368-374, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32188941

RESUMO

Two-dimensional van der Waals heterostructures (vdWHs) have attracted considerable interest1-4. However, most vdWHs reported so far  are created by an arduous micromechanical exfoliation and manual restacking process5, which-although versatile for proof-of-concept demonstrations6-16 and fundamental studies17-30-is clearly not scalable for practical technologies. Here we report a general synthetic strategy for two-dimensional vdWH arrays between metallic transition-metal dichalcogenides (m-TMDs) and semiconducting TMDs (s-TMDs). By selectively patterning nucleation sites on monolayer or bilayer s-TMDs, we precisely control the nucleation and growth of diverse m-TMDs with designable periodic arrangements and tunable lateral dimensions at the predesignated spatial locations, producing a series of vdWH arrays, including VSe2/WSe2, NiTe2/WSe2, CoTe2/WSe2, NbTe2/WSe2, VS2/WSe2, VSe2/MoS2 and VSe2/WS2. Systematic scanning transmission electron microscopy studies reveal nearly ideal vdW interfaces with widely tunable moiré superlattices. With the atomically clean vdW interface, we further show that the m-TMDs function as highly reliable synthetic vdW contacts for the underlying WSe2 with excellent device performance and yield, delivering a high ON-current density of up to 900 microamperes per micrometre in bilayer WSe2 transistors. This general synthesis of diverse two-dimensional vdWH arrays provides a versatile material platform for exploring exotic physics and promises a scalable pathway to high-performance devices.

3.
Cell Mol Life Sci ; 81(1): 32, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214780

RESUMO

BACKGROUND: Dysbiosis of gut microbiota is frequent in liver cirrhosis (LC) patients, and splenectomy (SP) has been reported to improve LC. Herein, we report the effects of SP on gut microbiota, especially on Veillonella parvula, a Gram-negative coccus of the gastrointestinal tract, in LC mice, and the underlying mechanism. METHODS: LC mice models were induced by tail vein injection of concanavalin A (ConA), followed by SP. 16 s rRNA sequencing was conducted to analyze the effects of ConA induction and SP on mouse gut microbiota and the gene expression affected by gut microbiota. LC mice receiving SP were gavaged with Veillonella parvula. Likewise, hepatic stellate cells (HSC) and hepatocytes (HC) were induced with conditioned medium (CM) of Veillonella parvula. RESULTS: SP alleviated LC in mice by restoring gut barrier function and maintaining gut microbiota balance, with Veillonella as the key genus. The Veillonella parvula gavage on LC mice reversed the ameliorative effect of SP. The CM of Veillonella parvula promoted the activation of HSC and the release of IL-6, IL-1ß, and TNF-α. Also, the CM of Veillonella parvula induced HC pyroptosis and the release of ALT and AST. Veillonella parvula represented an imbalance in the gut microbiota, thus enhancing gut-derived endotoxins in the liver with the main target being Tlr4/Nlrp3. Inhibition of Tlr4 blocked Veillonella parvula-induced HC damage, HSC activation, and subsequent LC progression. CONCLUSION: SP-mediated gut microbiota regulation ameliorates ConA-related LC progression by inhibiting Tlr4/Nlrp3 in the liver.


Assuntos
Microbioma Gastrointestinal , Veillonella , Humanos , Animais , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Esplenectomia , Receptor 4 Toll-Like/metabolismo , Cirrose Hepática/terapia
4.
Nano Lett ; 24(25): 7716-7723, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38848111

RESUMO

Mixed-dimensional heterostructures integrate materials of diverse dimensions with unique electronic functionalities, providing a new platform for research in electron transport and optoelectronic detection. Here, we report a novel covalently bonded one-dimensional/two-dimensional (1D/2D) homojunction structure with robust junction contacts, which exhibits wide-spectrum (from the visible to near-infrared regions), self-driven photodetection, and polarization-sensitive photodetection capabilities. Benefiting from the ultralow dark current at zero bias voltage, the on/off ratio and detectivity of the device reach 1.5 × 103 and 3.24 × 109 Jones, respectively. Furthermore, the pronounced anisotropy of the WSe2 1D/2D homojunction is attributed to its low symmetry, enabling polarization-sensitive detection. In the absence of any external bias voltage, the device exhibits strong linear dichroism for wavelengths of 638 and 808 nm, with anisotropy ratios of 2.06 and 1.96, respectively. These results indicate that such mixed-dimensional structures can serve as attractive building blocks for novel optoelectronic detectors.

5.
Small ; : e2309620, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294996

RESUMO

2D A 2 III B 3 VI ${\mathrm{A}}_2^{{\mathrm{III}}}{\mathrm{B}}_3^{{\mathrm{VI}}}$ compounds (A = Al, Ga, In, and B = S, Se, and Te) with intrinsic structural defects offer significant opportunities for high-performance and functional devices. However, obtaining 2D atomic-thin nanoplates with non-layered structure on SiO2 /Si substrate at low temperatures is rare, which hinders the study of their properties and applications at atomic-thin thickness limits. In this study, the synthesis of ultrathin, non-layered α-In2 Te3  nanoplates is demonstrated using a BiOCl-assisted chemical vapor deposition method at a temperature below 350 °C on SiO2 /Si substrate. Comprehensive characterization results confirm the high-quality single crystal is the low-temperature cubic phase α-In2 Te3 , possessing a noncentrosymmetric defected ZnS structure with good second harmonic generation. Moreover, α-In2 Te3 is revealed to be a p-type semiconductor with a direct and narrow bandgap value of 0.76 eV. The field effect transistor exhibits a high mobility of 18 cm2 V-1  s-1 , and the photodetector demonstrates stable photoswitching behavior within a broadband photoresponse from 405 to 1064 nm, with a satisfactory response time of τrise = 1 ms. Notably, the α-In2 Te3 nanoplates exhibit good stability against ambient environments. Together, these findings establish α-In2 Te3 nanoplates as promising candidates for next-generation high-performance photonics and electronics.

6.
J Asian Nat Prod Res ; 26(4): 510-518, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37705345

RESUMO

Eriocitrin is a flavonoid glycoside with strong antioxidant capacity that has a variety of pharmacological activities, such as hypolipidemic, anticancer and anti-inflammatory effects. We found that the gut microbiota could rapidly metabolize eriocitrin. By using LC/MSn-IT-TOF, we identified three metabolites of eriocitrin metabolized in the intestinal microbiota: eriodictyol-7-O-glucoside, eriodictyol, and dihydrocaffeic acid. By comparing these two metabolic pathways of eriocitrin (the gut microbiota and liver microsomes), the intestinal microbiota may be the primary metabolic site of eriocitrin metabolism. These findings provide a theoretical foundation for the study of pharmacologically active substances.


Assuntos
Flavanonas , Microbioma Gastrointestinal , Antioxidantes/farmacologia , Flavonoides/farmacologia , Biotransformação
7.
Molecules ; 29(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38611784

RESUMO

A new structurally simple fluorescent CP probe based on chromone was designed and synthesized, and its structure was fully characterized using various analytical techniques. The CP probe displays a high selectivity and sensitivity for sensing Fe3+ with a "turn-off" fluorescence response over other metal ions in a DMSO/H2O (4:1, v/v) solution. The experiment results show that the CP probe is stable over a wide pH range of 2.0-12.0. The detection limit for Fe3+ was calculated to be 0.044 µmol•L-1. The molar ratio method indicated that the binding mode between the CP probe and Fe3+ is a 1:1 complex formation. HR-MS and density functional theory (DFT) calculations were also performed to further confirm the recognition mechanism. Both fluorescence imaging experiments and the MTT assay demonstrated that the CP probe was suitable for detecting intracellular Fe3+ and no significant cytotoxicity in living cells.


Assuntos
Cromonas , Imagem Óptica , Corantes Fluorescentes , Reconhecimento Psicológico , Projetos de Pesquisa
8.
Angew Chem Int Ed Engl ; 63(7): e202317773, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38116827

RESUMO

Enzyme-activatable near-infrared (NIR) fluorescent probes and photosensitizers (PSs) have emerged as promising tools for molecular imaging and photodynamic therapy (PDT). However, in living organisms selective retention or even enrichment of these reagents after enzymatic activation at or near sites of interest remains a challenging task. Herein, we integrate non-covalent and covalent retention approaches to introduce a novel "1-to-3" multi-effect strategy-one enzymatic stimulus leads to three types of effects-for the design of an enzyme-activatable NIR probe or PS. Using this strategy, we have constructed an alkaline phosphatase (ALP)-activatable NIR fluorogenic probe and a NIR PS, which proved to be selectively activated by ALP to switch on NIR fluorescence or photosensitizing ability, respectively. Additionally, these reagents showed significant enrichment (over 2000-fold) in ALP-overexpressed tumor cells compared to the culture medium, accompanied by massive depletion of intracellular thiols, the major antioxidants in cells. The investigation of this ALP-activatable NIR PS in an in vivo PDT model resulted in complete suppression of HeLa tumors and full recovery of all tested mice. Encouragingly, even a single administration of this NIR PS was sufficient to completely suppress tumors in mice, demonstrating the high potential of this strategy in biomedical applications.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Humanos , Camundongos , Animais , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Células HeLa , Corantes Fluorescentes , Fosfatase Alcalina
9.
Biochem Biophys Res Commun ; 672: 54-64, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37336125

RESUMO

Insulin resistance and many metabolic disorders are causally linked to mitochondrial dysfunction or defective mitochondrial quality control. Mitophagy is a highly selective mechanism that recognizes and removes damaged mitochondria to maintain mitochondrial homeostasis. Here, we addressed the potential role of FUNDC1, a mediator of mitophagy, in pancreatic ß-cell dysfunction under lipotoxicity. In pancreatic MIN6 cells, FUNDC1 deficiency aggravated palmitate-induced mitochondrial dysfunction, which led to cell death and insulin insensitivity. Interestingly, FUNDC1 overexpression prevented these cellular harms brought on by palmitate. In mice models, pancreatic-specific FUNDC1 overexpression alleviated high-fat diet (HFD)-induced insulin resistance and obesity. Mechanistically, pancreatic-specific overexpression of FUNDC1 ameliorated mitochondrial defects and endoplasmic reticulum (ER) stress upon HFD. Our research indicates that FUNDC1 plays an essential role in apoptosis and dysfunction of pancreatic ß-cells via modulating lipotoxicity-induced mitochondrial defects.


Assuntos
Resistência à Insulina , Camundongos , Animais , Proteínas Mitocondriais/metabolismo , Mitocôndrias/metabolismo , Mitofagia/fisiologia , Palmitatos/metabolismo , Proteínas de Membrana/metabolismo
10.
J Magn Reson Imaging ; 58(4): 1303-1313, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36876593

RESUMO

BACKGROUND: The volume doubling time (VDT) of breast cancer was most frequently calculated using the two-dimensional (2D) diameter, which is not reliable for irregular tumors. It was rarely investigated using three-dimensional (3D) imaging with tumor volume on serial magnetic resonance imaging (MRI). PURPOSE: To investigate the VDT of breast cancer using 3D tumor volume assessment on serial breast MRIs. STUDY TYPE: Retrospective. SUBJECTS: Sixty women (age at diagnosis: 57 ± 10 years) with breast cancer, assessed by two or more breast MRI examinations. The median interval time was 791 days (range: 70-3654 days). FIELD STRENGTH/SEQUENCE: 3-T, fast spin-echo T2-weighted imaging (T2WI), single-shot echo-planar diffusion-weighted imaging (DWI), and gradient echo dynamic contrast-enhanced imaging. ASSESSMENT: Three radiologists independently reviewed the morphological, DWI, and T2WI features of lesions. The whole tumor was segmented to measure the volume on contrast-enhanced images. The exponential growth model was fitted in the 11 patients with at least three MRI examinations. The VDT of breast cancer was calculated using the modified Schwartz equation. STATISTICAL TESTS: Mann-Whitney U test, Kruskal-Wallis test, Chi-squared test, intraclass correlation coefficients, and Fleiss kappa coefficients. A P-value <0.05 was considered statistically significant. The exponential growth model was evaluated using the adjusted R2 and root mean square error (RMSE). RESULTS: The median tumor diameter was 9.7 mm and 15.2 mm on the initial and final MRI, respectively. The median adjusted R2 and RMSE of the 11 exponential models were 0.97 and 15.8, respectively. The median VDT was 540 days (range: 68-2424 days). For invasive ductal carcinoma (N = 33), the median VDT of the non-luminal type was shorter than that of the luminal type (178 days vs. 478 days). On initial MRI, breast cancer manifesting as a focus or mass lesion showed a shorter VDT than that of a non-mass enhancement (NME) lesion (median VDT: 426 days vs. 665 days). DATA CONCLUSION: A shorter VDT was observed in breast cancer manifesting as focus or mass as compared to an NME lesion. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carga Tumoral , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Mama/diagnóstico por imagem , Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos
11.
Eur Radiol ; 33(10): 7077-7088, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37166496

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant solid tumor that lacks early diagnostic methods. Recently, targeted immunotherapy and radiotherapy have been integrated with radionuclide-antibody conjugate drugs, which can be used for targeted diagnosis and dynamic imaging of tumors. CEACAM6 is overexpressed in pancreatic tumors and is a potential theranostic target for PDAC. We aimed to develop a novel targeted carrier for theranostics of PDAC and other solid tumors. METHODS: Based on camelid heavy-chain-only antibodies, we developed a CEACAM6-targeting recombinant antibody NY004, and evaluated it as a novel antibody-carrier for imaging and therapy of cancer in tumor models. We labeled NY004 with theranostic nuclides and applied this self-developed antibody platform in diagnostic imaging and antitumor assessment in PDAC models. RESULTS: Through microPET, IHC, and biodistribution assays, targeting and biodistribution of [89Zr]-NY004 in solid tumors including PDAC was examined, and the investigated tumors were all CEACAM6-positive malignancies. We found that NY004 was suitable for use as a drug carrier for radioimmunotheranostics. Our study showed that NY004 was characterized by high targeted uptake and a long retention time in PANC-1 tumors (up to 6 days post-injection), with good specificity and high imaging efficiency. Therapeutic evaluation of the radionuclide-labeled antibody drug [177Lu]-NY004 in PDAC tumor-bearing model revealed that NY004 had high and prolonged uptake in tumors, relatively low non-target organ uptake, and good anti-tumor efficacy. CONCLUSION: As a drug platform for radiotheranostics, CEACAM6-specific antibody NY004 met the requirements of easy-labeling, targeting specificity, and effective persistence in pancreatic adenocarcinoma tissues. KEY POINTS: • [89Zr]-NY004 has good specificity and high imaging efficiency, and is characterized by high tumor-targeting uptake and a long tumor retention time as a PET molecular imaging tracer. • Therapeutic radionuclide-conjugated antibody drug [177Lu]-NY004 has high uptake and prolonged uptake duration in tumors, low non-target organ uptake, and significant tumor-inhibiting efficacy in PDAC model. • The self-developed antibody structure NY004 is a promising drug platform for radioimmunotheranostics of CEACAM6-positive tumors including pancreatic ductal adenocarcinoma.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Adenocarcinoma/patologia , Distribuição Tecidual , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/terapia , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Pancreáticas
12.
Mol Breed ; 43(5): 37, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37312749

RESUMO

The genetic base of soybean cultivars (Glycine max (L.) Merr.) has been narrowed through selective domestication and specific breeding improvement, similar to other crops. This presents challenges in breeding new cultivars with improved yield and quality, reduced adaptability to climate change, and increased susceptibility to diseases. On the other hand, the vast collection of soybean germplasms offers a potential source of genetic variations to address those challenges, but it has yet to be fully leveraged. In recent decades, rapidly improved high-throughput genotyping technologies have accelerated the harness of elite variations in soybean germplasm and provided the important information for solving the problem of a narrowed genetic base in breeding. In this review, we will overview the situation of maintenance and utilization of soybean germplasms, various solutions provided for different needs in terms of the number of molecular markers, and the omics-based high-throughput strategies that have been used or can be used to identify elite alleles. We will also provide an overall genetic information generated from soybean germplasms in yield, quality traits, and pest resistance for molecular breeding.

13.
Cell Mol Biol (Noisy-le-grand) ; 69(5): 112-118, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37571892

RESUMO

It was to explore the effect of neoadjuvant therapy (NAT) on serum-related indicators and prognosis of patients with locally advanced esophageal cancer (EC). 400 EC patients were grouped as controls (295 cases, radical EC resection alone) and research group (105 cases, NAT plus radical EC resection). The levels of serum carbohydrate antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA), and cytokeratin 19 fragment antigen 21-1 (CYFRA21-1), programmed death-1 (PD-1), PD-2, transforming growth factor-ß1 (TGF-ß1), and squamous cell carcinoma (SCC) antigen were detected before and after treatment. The follow-up lasted for 3 years. The quality of life (QoL) was evaluated by QLQ-OES24. The recurrence rate, recurrence time, overall survival rate (SR), disease-free SR, and complication rate were compared. Compared with controls, the levels of serum CA19-9, CEA, CYFRA21-1, PD-1, PD-2, TGF-ß1, and SCC were decreased, the QoL score was increased 3 years post-treatment, and the recurrence time was prolonged in the research group (P<0.05). The R0 resection rate, recurrence rate, 3-year overall SR, and disease-free SR of the two groups were 67.12% vs 85.71%, 21.36% vs 6.67%, 56.27% vs 77.14%, 29.83% vs 45.71%, respectively (P<0.05). The complication rates of the two groups were 32.54% and 29.52%, respectively (P>0.05). NAT plus radical resection of EC can effectively reduce the level of serum oncology markers in patients with locally advanced EC, reduce the postoperative recurrence rate, improve QoL and SR, and has high safety.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Antígeno Carcinoembrionário , Fator de Crescimento Transformador beta1 , Qualidade de Vida , Biomarcadores Tumorais , Antígeno CA-19-9 , Fator de Crescimento Transformador beta , Terapia Neoadjuvante , Receptor de Morte Celular Programada 1 , Carcinoma de Células Escamosas/tratamento farmacológico , Queratina-19 , Neoplasias Esofágicas/tratamento farmacológico , Fatores de Crescimento Transformadores , Células Epiteliais/patologia
14.
J Comput Assist Tomogr ; 47(2): 322-328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36957971

RESUMO

OBJECTIVE: This study aimed to investigate the correlation between apparent diffusion coefficient (ADC) and the Ki-67 proliferation index with the pathologic grades of pediatric glioma and to compare their diagnostic performance in differentiating grades of pediatric glioma. PATIENTS AND METHODS: Magnetic resonance imaging examinations and histopathologies of 121 surgically treated pediatric gliomas (87 low-grade gliomas [LGGs; grades 1 and 2] and 34 high-grade gliomas [HGGs; grades 3 and 4]) were retrospectively reviewed. The mean tumor ADC (ADCmean), minimum tumor ADC (ADCmin), tumor/normal brain ADC ratio (ADC ratio), and value of the Ki-67 proliferation index of LGGs and HGGs were compared. Correlation coefficients were calculated for ADC parameters and Ki-67 values. The receiver operating characteristic curve was used to determine the diagnostic value of ADCmean, ADCmin, ADC ratio, and Ki-67 proliferation index for differentiating LGGs and HGGs. RESULTS: The ADC values were significantly negatively correlated with glioma grade, and the Ki-67 proliferation index had a significant positive correlation with glioma grade. A significant negative correlation was observed between ADCmean and Ki-67 proliferation index, between ADCmin and Ki-67 proliferation index, and between ADC ratio and Ki-67 proliferation index. The receiver operating characteristic analysis demonstrated moderate to good accuracy for ADCmean in discriminating LGGs from HGGs (area under the curve [AUC], 0.875; sensitivity, 79.3%; specificity, 82.4%; accuracy, 80.2%; positive predictive value [PPV], 92.0%; and negative predictive value [NPV], 60.9% [cutoff value, 1.187] [×10-3 mm2/s]). Minimum tumor ADC showed very good to excellent accuracy with AUC of 0.946, sensitivity of 86.2%, specificity of 94.1%, accuracy of 88.4%, PPV of 97.4%, and NPV of 72.7% (cutoff value, 0.970) (×10-3 mm2/s). The ADC ratio showed moderate to good accuracy with AUC of 0.854, sensitivity of 72.4%, specificity of 88.2%, accuracy of 76.9%, PPV of 94.0%, and NPV of 55.6% (cutoff value, 1.426). For the parameter of the Ki-67 proliferation index, in discriminating LGGs from HGGs, very good to excellent diagnostic accuracy was observed (AUC, 0.962; sensitivity, 94.1%; specificity, 89.7%; accuracy, 90.9%; PPV, 97.5%; and NPV, 78.0% [cutoff value, 7]). CONCLUSIONS: Apparent diffusion coefficient parameters and the Ki-67 proliferation index were significantly correlated with histological grade in pediatric gliomas. Apparent diffusion coefficient was closely correlated with the proliferative potential of pediatric gliomas. In addition, ADCmin showed superior performance compared with ADCmean and ADC ratio in differentiating pediatric glioma grade, with a close diagnostic efficacy to the Ki-67 proliferation index.


Assuntos
Neoplasias Encefálicas , Imagem de Difusão por Ressonância Magnética , Glioma , Criança , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Proliferação de Células , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Glioma/patologia , Antígeno Ki-67 , Gradação de Tumores , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
BMC Anesthesiol ; 23(1): 242, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468887

RESUMO

BACKGROUND: The aim of this study was to investigate the prognostic role of platelet to albumin ratio (PAR) and in persistent acute kidney injury (pAKI) of patients admitted to the intensive care unit (ICU). METHODS: We involved pAKI patients from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database and eICU Collaborative Research Database (eICU-CRD). Receiver operating curve (ROC) analysis was performed to evaluate the optimal cut-off PAR. RESULTS: A total of 7,646 patients were finally included in the present study. The optimal cut-off value of PAR was 7.2. The high-PAR group was associated with pAKI (hazard ratio [HR]: 3.25, 95% CI: 2.85-3.72, P < 0.001). We also performed this in the validation cohort, the results further confirmed that the high-PAR group was associated with pAKI (HR: 2.24, 95% CI: 1.86-2.71, P < 0.001). The PAR exhibited good pAKI predictive abilities in the original cohort (C-index: 0.726, 95%CI: 0.714-0.739) and in the validation cohort (C-index: 0.744, 95%CI:0.722-0.766) Moreover, as a systemic inflammatory indicator, PAR depicted better predictive ability compared to other systemic inflammatory indicators. CONCLUSION: The present study manifested that elevated PAR could predicts pAKI in patients admitted to ICU. PAR may be an easily obtained and useful biomarker to clinicians for the early identification of pAKI.


Assuntos
Injúria Renal Aguda , Albuminas , Contagem de Plaquetas , Humanos , Injúria Renal Aguda/diagnóstico , Biomarcadores , Unidades de Terapia Intensiva , Prognóstico , Estudos Retrospectivos , Curva ROC
16.
Mikrochim Acta ; 190(12): 484, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38006440

RESUMO

Developing an intelligent, sensitive, and visual strategy for quickly identifying anthrax biomarkers is crucial for ensuring food safety and preventing disease outbreaks. Herein, a smartphone-integrated ratiometric fluorescent sensing platform based on bimetallic metal-organic framework (Eux/Tb1-x-MOF) nanowires was designed for specific recognition of pyridine-2,6-dicarboxylic acid (DPA, anthrax biomarker). The Eux/Tb1-x-MOF was prepared by coordinating Eu3+ and Tb3+ with BBDC ligands, which exhibited a uniform fibrous morphology and dual-emission fluorescence at 543 and 614 nm. After the introduction of DPA, the red emission at 614 nm displayed obvious fluorescence quenching, while the green emission at 543 nm was gradually enhanced. The ratiometric sensing offered a wide linear equation in the range of 0.06-15 µg/mL and a low detection limit (LOD) of 20.69 ng/mL. Furthermore, a portable smartphone installing the color recognition application can achieve sensitive, real-time, and visual detection of DPA. As a simple and effective smartphone-assisted sensing platform, this work holds admirable promise to broaden the applications in biomarker real-time determinations and other fields.


Assuntos
Antraz , Estruturas Metalorgânicas , Nanofios , Humanos , Antraz/diagnóstico , Fluorescência , Corantes Fluorescentes , Smartphone , Biomarcadores
17.
Molecules ; 28(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36985399

RESUMO

The DFT method is employed to study the adsorption and reaction behaviors of HC2O4-, H2PO4-, HSO4- and H2O on neutral and anodic aluminum slabs. With the exception of adsorption, the three acid radicals can successively take the two H atoms from the adsorbed H2O on the anodic aluminum slabs, which is the key step of the formation of anodic alumina. The dehydrogenation reaction is dominated by the Coulombic interaction of O and H, respectively belonging to acid radicals and the adsorbed H2O or OH, rather than by the interaction of electronic orbits located on the two kinds of atoms. The experiment of anodic polarization of aluminum verifies the calculation result well.

18.
J Cell Physiol ; 237(2): 1471-1485, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34698390

RESUMO

Alcohol metabolism causes hepatocytes to release damage-associated molecular patterns (DAMPs). This includes mitochondrial DNA (mtDNA), which is generated and released from damaged hepatocytes and contributes to liver injury by producing proinflammatory cytokines. STING is a pattern recognition receptor of DAMPs known to control the induction of innate immunity in various pathological processes. However, the expression profile and functions of STING in the Gao binge ethanol model remain poorly understood. We demonstrated that STING is upregulated in the Gao binge ethanol model. STING functions as an mtDNA sensor in the Kupffer cells of the liver and induces STING-signaling pathway-dependent inflammation and further aggravates hepatocyte apoptosis in the Gao binge ethanol model. This study provides novel insights into predicting disease progression and developing targeted therapies for alcoholic liver injury.


Assuntos
Etanol , Hepatócitos , Animais , DNA Mitocondrial/genética , Hepatócitos/metabolismo , Inflamação/patologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
19.
Nat Mater ; 20(6): 818-825, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33649563

RESUMO

The discovery of intrinsic ferromagnetism in ultrathin two-dimensional van der Waals crystals opens up exciting prospects for exploring magnetism in the ultimate two-dimensional limit. Here, we show that environmentally stable CrSe2 nanosheets can be readily grown on a dangling-bond-free WSe2 substrate with systematically tunable thickness down to the monolayer limit. These CrSe2/WSe2 heterostructures display high-quality van der Waals interfaces with well-resolved moiré superlattices and ferromagnetic behaviour. We find no apparent change in surface roughness or magnetic properties after months of exposure in air. Our calculations suggest that charge transfer from the WSe2 substrate and interlayer coupling within CrSe2 play a critical role in the magnetic order in few-layer CrSe2 nanosheets. The highly controllable growth of environmentally stable CrSe2 nanosheets with tunable thickness defines a robust two-dimensional magnet for fundamental studies and potential applications in magnetoelectronic and spintronic devices.

20.
Opt Lett ; 47(14): 3419-3422, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838694

RESUMO

We demonstrate two all-fiber low-frequency shift schemes based on the acousto-optic interaction in a few-mode fiber (FMF). Two acoustically induced fiber gratings (AIFGs) are cascaded in reverse to achieve an efficient cycle conversion between LP11 and LP01 core modes in the FMF while obtaining a frequency shift of 1.8 MHz. In addition, a long-period fiber grating (LPFG) is employed to replace the AIFG, which achieves a lower frequency shift of 0.9 MHz, and its tunable wavelength range exceeds 100 nm. Both schemes show the characteristics of an upward frequency shift. Moreover, we also present a heterodyne detection system based on the above frequency shift schemes, which is verified in response to micro-vibration signals ranging from tens to hundreds of kilohertz, as well as speech signals in a lower frequency range. The experimental results show that these all-fiber frequency shift schemes have potential applications, such as in fiber optic hydrophones, laser speech detection, and fiber optic sensors.

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