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1.
Nature ; 593(7858): 211-217, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33981050

RESUMEN

Advanced beyond-silicon electronic technology requires both channel materials and also ultralow-resistance contacts to be discovered1,2. Atomically thin two-dimensional semiconductors have great potential for realizing high-performance electronic devices1,3. However, owing to metal-induced gap states (MIGS)4-7, energy barriers at the metal-semiconductor interface-which fundamentally lead to high contact resistance and poor current-delivery capability-have constrained the improvement of two-dimensional semiconductor transistors so far2,8,9. Here we report ohmic contact between semimetallic bismuth and semiconducting monolayer transition metal dichalcogenides (TMDs) where the MIGS are sufficiently suppressed and degenerate states in the TMD are spontaneously formed in contact with bismuth. Through this approach, we achieve zero Schottky barrier height, a contact resistance of 123 ohm micrometres and an on-state current density of 1,135 microamps per micrometre on monolayer MoS2; these two values are, to the best of our knowledge, the lowest and highest yet recorded, respectively. We also demonstrate that excellent ohmic contacts can be formed on various monolayer semiconductors, including MoS2, WS2 and WSe2. Our reported contact resistances are a substantial improvement for two-dimensional semiconductors, and approach the quantum limit. This technology unveils the potential of high-performance monolayer transistors that are on par with state-of-the-art three-dimensional semiconductors, enabling further device downscaling and extending Moore's law.

2.
Nature ; 580(7805): 614-620, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32350477

RESUMEN

Epitaxial heterostructures based on oxide perovskites and III-V, II-VI and transition metal dichalcogenide semiconductors form the foundation of modern electronics and optoelectronics1-7. Halide perovskites-an emerging family of tunable semiconductors with desirable properties-are attractive for applications such as solution-processed solar cells, light-emitting diodes, detectors and lasers8-15. Their inherently soft crystal lattice allows greater tolerance to lattice mismatch, making them promising for heterostructure formation and semiconductor integration16,17. Atomically sharp epitaxial interfaces are necessary to improve performance and for device miniaturization. However, epitaxial growth of atomically sharp heterostructures of halide perovskites has not yet been achieved, owing to their high intrinsic ion mobility, which leads to interdiffusion and large junction widths18-21, and owing to their poor chemical stability, which leads to decomposition of prior layers during the fabrication of subsequent layers. Therefore, understanding the origins of this instability and identifying effective approaches to suppress ion diffusion are of great importance22-26. Here we report an effective strategy to substantially inhibit in-plane ion diffusion in two-dimensional halide perovskites by incorporating rigid π-conjugated organic ligands. We demonstrate highly stable and tunable lateral epitaxial heterostructures, multiheterostructures and superlattices. Near-atomically sharp interfaces and epitaxial growth are revealed by low-dose aberration-corrected high-resolution transmission electron microscopy. Molecular dynamics simulations confirm the reduced heterostructure disorder and larger vacancy formation energies of the two-dimensional perovskites in the presence of conjugated ligands. These findings provide insights into the immobilization and stabilization of halide perovskite semiconductors and demonstrate a materials platform for complex and molecularly thin superlattices, devices and integrated circuits.

3.
Cardiovasc Diabetol ; 23(1): 131, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637777

RESUMEN

BACKGROUND: Serum uric acid (SUA) is an important pathogenetic and prognostic factor for heart failure (HF). Gender differences are apparent in HF. Furthermore, gender differences also exist in the association between SUA and prognosis in various cardiovascular diseases. However, the gender difference for SUA in the prediction of long-term prognosis in HF is still ambiguous. METHODS: A total of 1593 HF patients (897 men, 696 women) from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 cycle were enrolled in our final analysis. Participants were categorized according to gender-specific SUA tertile. We assessed the association between SUA and long-term prognosis of HF patients, defined as all-cause mortality and cardiovascular mortality, in different genders via Kaplan-Meier curve analysis, Cox proportional hazard model, and Fine-Gray competing risk model. The restricted cubic spline (RCS) was performed to investigate the dose-response relationship between SUA and outcomes. RESULTS: Gender differences exist in demographic characteristics, clinical parameters, laboratory tests, and medication of HF patients. After a median follow-up of 127 months (95% CI 120-134 months), there were 853 all-cause deaths (493 events in men, 360 events in women) and 361 cardiovascular deaths (206 events in men, 155 events in women). Kaplan-Meier analysis showed that SUA had gender difference in the prediction of cardiovascular mortality (Log-rank p < 0.001, for male, Log-rank p = 0.150, for female), but not in all-cause mortality. Multivariate Cox regression analysis revealed that elevated SUA levels were associated with higher all-cause mortality and cardiovascular mortality in men (HR 1.11, 95% CI 1.05-1.18, p < 0.001, for all-cause death; HR 1.18, 95% CI 1.09-1.28, p < 0.001, for cardiovascular death), but not in women (HR 1.05, 95% CI 0.98-1.12, p = 0.186, for all-cause death; HR 1.01, 95% CI 0.91-1.12, p = 0.902, for cardiovascular death). Even using non-cardiovascular death as a competitive risk, adjusted Fine-Gray model also illustrated that SUA was an independent predictor of cardiovascular death in men (SHR 1.17, 95% CI 1.08-1.27, p < 0.001), but not in women (SHR 0.98, 95% CI 0.87 - 1.10, p = 0.690). CONCLUSIONS: Gender differences in the association between SUA and long-term prognosis of HF existed. SUA was an independent prognostic predictor for long-term outcomes of HF in men, but not in women.


Asunto(s)
Enfermedades Cardiovasculares , Insuficiencia Cardíaca , Humanos , Masculino , Femenino , Ácido Úrico , Factores Sexuales , Encuestas Nutricionales , Factores de Riesgo , Pronóstico , Insuficiencia Cardíaca/tratamiento farmacológico
4.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34353912

RESUMEN

Technology advancements in history have often been propelled by material innovations. In recent years, two-dimensional (2D) materials have attracted substantial interest as an ideal platform to construct atomic-level material architectures. In this work, we design a reaction pathway steered in a very different energy landscape, in contrast to typical thermal chemical vapor deposition method in high temperature, to enable room-temperature atomic-layer substitution (RT-ALS). First-principle calculations elucidate how the RT-ALS process is overall exothermic in energy and only has a small reaction barrier, facilitating the reaction to occur at room temperature. As a result, a variety of Janus monolayer transition metal dichalcogenides with vertical dipole could be universally realized. In particular, the RT-ALS strategy can be combined with lithography and flip-transfer to enable programmable in-plane multiheterostructures with different out-of-plane crystal symmetry and electric polarization. Various characterizations have confirmed the fidelity of the precise single atomic layer conversion. Our approach for designing an artificial 2D landscape at selective locations of a single layer of atoms can lead to unique electronic, photonic, and mechanical properties previously not found in nature. This opens a new paradigm for future material design, enabling structures and properties for unexplored territories.

5.
Mikrochim Acta ; 191(7): 433, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951214

RESUMEN

A cancer-targeted glutathione (GSH)-gated theranostic probe (CGT probe) for intracellular miRNA imaging and combined treatment of self-sufficient starvation therapy (ST) and chemodynamic therapy (CDT) was developed. The CGT probe is constructed using MnO2 nanosheet (MS) as carrier material to adsorb the elaborately designed functional DNAs. It can be internalized by cancer cells via specific recognition between the AS1411 aptamer and nucleolin. After CGT probe entering the cancer cells, the overexpressed GSH, as gate-control, can degrade MS to Mn2+ which can be used for CDT by Fenton-like reaction. Simultaneously, Mn2+-mediated CDT can further cascade with the enzyme-like activities (catalase-like activity and glucose oxidase-like activity) of CGT probe, achieving self-sufficient ST/CDT synergistic therapy. Meanwhile, the anchored DNAs are released, achieving in situ signal amplification via disubstituted-catalytic hairpin assembly (DCHA) and FRET (fluorescence resonance energy transfer) imaging of miR-21. The in vitro and in vivo experiments demonstrated that accurate and sensitive miRNA detection can be achieved using the CGT probe. Overall, the ingenious CGT probe opens a new avenue for the development of early clinical diagnosis and cancer therapy.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Glutatión , Compuestos de Manganeso , MicroARNs , Óxidos , Humanos , Glutatión/química , Glutatión/metabolismo , Animales , Compuestos de Manganeso/química , Óxidos/química , Aptámeros de Nucleótidos/química , Ratones , Ratones Desnudos , Nanomedicina Teranóstica/métodos , Nucleolina , Neoplasias/diagnóstico por imagen , Nanoestructuras/química , Oligodesoxirribonucleótidos/química , Ratones Endogámicos BALB C , Colorantes Fluorescentes/química
6.
Anal Chem ; 95(20): 8097-8104, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37171156

RESUMEN

Long noncoding RNAs (lncRNAs) play pivotal roles in multifarious physiological and pathological processes, and their aberrant expression may disturb the normal regulatory network of gene expression to induce diverse human diseases. Herein, we construct a fluorescent light-up biosensor with a low background for label-free detection of lncRNAs by coupling duplex-specific nuclease (DSN)-assisted target recycling amplification with transcription-driven synthesis of fluorogenic RNA aptamer-Corns. We design two linear probes, including a capture probe for initiating a cyclic cleavage reaction and a linear template for transcribing RNA aptamer-Corn. Target lncRNA is recognized by capture probes assembled on magnetic bead (MB) surfaces to trigger a DSN-assisted cyclic cleavage reaction, releasing abundant T7 promoter sequences. After magnetic separation, free T7 promoter hybridizes with a linear template to induce efficient transcription amplification with the assistance of T7 RNA polymerase, producing numerous fluorogenic RNA aptamer-Corns that can light up small-molecule fluorogens 3,5-difluoro-4-hydroxybenzylidene-imidazolinone-2-oxime (DFHO). Notably, the introduction of MBs facilitates both the separation of cleaved capture probes and the enrichment/isolation of target lncRNAs from the complex biological matrix. Benefiting from the high efficiency of DSN/T7 RNA polymerase-mediated cascade amplification and high signal-to-background ratio of the Corn-DFHO complex, this biosensor is capable of sensitively quantifying lncRNA with a detection limit of 31.98 aM. Moreover, it can precisely quantify lncRNA at the single-cell level and even in complex biological samples, and it can differentiate tumor cells from normal cells. Importantly, this Corn-based biosensor is readily extended to detect other lncRNAs by altering capture probe sequences, opening a new avenue for molecular diagnosis.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Callosidades , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Zea mays/genética , Colorantes , Límite de Detección
7.
Anal Chem ; 95(35): 13201-13210, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37603851

RESUMEN

N6-Methyladenosine (m6A) demethylases can catalyze the removal of the methyl modification on m6A, and it is closely associated with the occurrence, proliferation, differentiation, and metastasis of malignancies. The m6A demethylases (e.g., fat mass and obesity-associated protein (FTO)) may act as a cancer biomarker and are crucial for anticancer drug screening and early clinical diagnosis. Herein, we demonstrate the construction of a quantum-dot-based Förster resonance energy-transfer (FRET) nanosensor through direct encoding of streptavidin-binding RNA aptamers (SA aptamers) for m6A demethylase detection. This nanosensor employs multiple Cy5-molecule-labeled SA aptamers as the building materials to construct the 605QD-RNA-Cy5 nanoassembly, and it exploits the hinder effect of m6A upon elongation and ligation reactions to distinguish m6A-containing RNA probes from demethylated RNA probes. When m6A demethylase is present, the m6A-containing RNA probes are demethylated to generate the demethylated RNA probes, initiating strand extension and ligation reactions to yield a complete transcription template for SA aptamers. Subsequently, a T7-assisted cascade transcription amplification reaction is activated to transcribe abundant SA aptamers with the incorporation of multiple Cy5 fluorophores. The Cy5-incorporated SA aptamers can self-assembly onto the streptavidin-coated 605QD surface to obtain the 605QD-SA aptamer-Cy5 nanoassemblies, resulting in the generation of distinct FRET signals. This nanosensor exhibits ultrahigh sensitivity and excellent specificity, and it can detect endogenous FTO at the single-cell level. Furthermore, this nanosensor can precisely measure enzyme kinetic parameters, screen m6A demethylase inhibitors, and differentiate the FTO expression between breast cancer patients and healthy individual tissues, offering a versatile platform for clinical diagnostic and drug discovery.


Asunto(s)
Aptámeros de Nucleótidos , Humanos , Estreptavidina , Transferencia Resonante de Energía de Fluorescencia , Sondas ARN , Adenosina , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética
8.
Nat Mater ; 21(8): 896-902, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35835818

RESUMEN

The colour centre platform holds promise for quantum technologies, and hexagonal boron nitride has attracted attention due to the high brightness and stability, optically addressable spin states and wide wavelength coverage discovered in its emitters. However, its application is hindered by the typically random defect distribution and complex mesoscopic environment. Here, employing cathodoluminescence, we demonstrate on-demand activation and control of colour centre emission at the twisted interface of two hexagonal boron nitride flakes. Further, we show that colour centre emission brightness can be enhanced by two orders of magnitude by tuning the twist angle. Additionally, by applying an external voltage, nearly 100% brightness modulation is achieved. Our ab initio GW and GW plus Bethe-Salpeter equation calculations suggest that the emission is correlated to nitrogen vacancies and that a twist-induced moiré potential facilitates electron-hole recombination. This mechanism is further exploited to draw nanoscale colour centre patterns using electron beams.


Asunto(s)
Compuestos de Boro , Color
9.
Phys Rev Lett ; 130(1): 016101, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36669218

RESUMEN

We report the development of deep-learning coherent electron diffractive imaging at subangstrom resolution using convolutional neural networks (CNNs) trained with only simulated data. We experimentally demonstrate this method by applying the trained CNNs to recover the phase images from electron diffraction patterns of twisted hexagonal boron nitride, monolayer graphene, and a gold nanoparticle with comparable quality to those reconstructed by a conventional ptychographic algorithm. Fourier ring correlation between the CNN and ptychographic images indicates the achievement of a resolution in the range of 0.70 and 0.55 Å. We further develop CNNs to recover the probe function from the experimental data. The ability to replace iterative algorithms with CNNs and perform real-time atomic imaging from coherent diffraction patterns is expected to find applications in the physical and biological sciences.


Asunto(s)
Aprendizaje Profundo , Nanopartículas del Metal , Electrones , Oro , Redes Neurales de la Computación , Algoritmos
10.
Proc Natl Acad Sci U S A ; 116(42): 20844-20849, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31575741

RESUMEN

Two-dimensional van der Waals materials have rich and unique functional properties, but many are susceptible to corrosion under ambient conditions. Here we show that linear alkylamines n-C m H2m+1NH2, with m = 4 through 11, are highly effective in protecting the optoelectronic properties of these materials, such as black phosphorus (BP) and transition-metal dichalcogenides (TMDs: WS2, 1T'-MoTe2, WTe2, WSe2, TaS2, and NbSe2). As a representative example, n-hexylamine (m = 6) can be applied in the form of thin molecular monolayers on BP flakes with less than 2-nm thickness and can prolong BP's lifetime from a few hours to several weeks and even months in ambient environments. Characterizations combined with our theoretical analysis show that the thin monolayers selectively sift out water molecules, forming a drying layer to achieve the passivation of the protected 2D materials. The monolayer coating is also stable in air, H2 annealing, and organic solvents, but can be removed by certain organic acids.

11.
Proc Natl Acad Sci U S A ; 116(9): 3437-3442, 2019 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-30755527

RESUMEN

The 2D van der Waals crystals have shown great promise as potential future electronic materials due to their atomically thin and smooth nature, highly tailorable electronic structure, and mass production compatibility through chemical synthesis. Electronic devices, such as field effect transistors (FETs), from these materials require patterning and fabrication into desired structures. Specifically, the scale up and future development of "2D"-based electronics will inevitably require large numbers of fabrication steps in the patterning of 2D semiconductors, such as transition metal dichalcogenides (TMDs). This is currently carried out via multiple steps of lithography, etching, and transfer. As 2D devices become more complex (e.g., numerous 2D materials, more layers, specific shapes, etc.), the patterning steps can become economically costly and time consuming. Here, we developed a method to directly synthesize a 2D semiconductor, monolayer molybdenum disulfide (MoS2), in arbitrary patterns on insulating SiO2/Si via seed-promoted chemical vapor deposition (CVD) and substrate engineering. This method shows the potential of using the prepatterned substrates as a master template for the repeated growth of monolayer MoS2 patterns. Our technique currently produces arbitrary monolayer MoS2 patterns at a spatial resolution of 2 µm with excellent homogeneity and transistor performance (room temperature electron mobility of 30 cm2 V-1 s-1 and on-off current ratio of 107). Extending this patterning method to other 2D materials can provide a facile method for the repeatable direct synthesis of 2D materials for future electronics and optoelectronics.

12.
Zhongguo Zhong Yao Za Zhi ; 46(9): 2363-2369, 2021 May.
Artículo en Zh | MEDLINE | ID: mdl-34047142

RESUMEN

Chinese traditional medicine compound is the main form of Chinese medicine clinical application. The elucidation of the effective components of traditional Chinese medicine is one of the key scientific issues to promote the modernization of traditional Chinese medicine. At present, there are many research ideas on the effective components of traditional Chinese medicine compounds. By analyzing the current status and existing problems of existing research ideas, the author proposes a "double reduction network pharmacology"(2 R network pharmacology) research method based on "prediction of dominant components-potential target selection". Chemical components with good properties were selected by ADMET property prediction technology, and compared with the blood components and target organ components to determine the dominant components with potential therapeutic effect, that is "reducing constituents"; the potential core regulatory pathway of traditional Chinese medicine compound was enriched by RNA-Seq technology combined with network database, and then the target of traditional Chinese medicine compound was mined based on the signal pathway, that is "reducing targets". To improve the efficiency and accuracy of effective component screening, the network relationship of "component target" was established by the related technology of network pharmacology. The purpose of this study is to provide practical research ideas and methods for clarifying the effective components of traditional Chinese medicine, revealing the law of compatibility of traditional Chinese medicine and clarifying the target of drug action.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Bases de Datos Factuales , Medicamentos Herbarios Chinos/farmacología , Simulación del Acoplamiento Molecular , Proyectos de Investigación
13.
J Am Chem Soc ; 142(41): 17499-17507, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32942848

RESUMEN

Interlayer coupling plays essential roles in the quantum transport, polaritonic, and electrochemical properties of stacked van der Waals (vdW) materials. In this work, we report the unconventional interlayer coupling in vdW heterostructures (HSs) by utilizing an emerging 2D material, Janus transition metal dichalcogenides (TMDs). In contrast to conventional TMDs, monolayer Janus TMDs have two different chalcogen layers sandwiching the transition metal and thus exhibit broken mirror symmetry and an intrinsic vertical dipole moment. Such a broken symmetry is found to strongly enhance the vdW interlayer coupling by as much as 13.2% when forming MoSSe/MoS2 HS as compared to the pristine MoS2 counterparts. Our noncontact ultralow-frequency Raman probe, linear chain model, and density functional theory calculations confirm the enhancement and reveal the origins as charge redistribution in Janus MoSSe and reduced interlayer distance. Our results uncover the potential of tuning interlayer coupling strength through Janus heterostacking.

14.
J Clin Lab Anal ; 34(11): e23500, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32815572

RESUMEN

BACKGROUND: This study aimed to evaluate the clinical role of long noncoding RNA (lncRNA) HULC in acute ischemic stroke (AIS). METHODS: LncRNA HULC in plasma samples from 215 first episode AIS patients and 215 age/gender-matched non-AIS controls was detected by reverse transcriptional-quantitative polymerase chain reaction (RT-qPCR). Then, in AIS patients, interleukin-6 and intercellular adhesion molecule 1 (ICAM1), as well as microRNA (miR) target of lncRNA HUCL (miR-9 and miR-195), were detected by enzyme-linked immunosorbent assay and RT-qPCR, respectively. Disease severity was assessed by National Institution of Health stroke scale (NIHSS) score. AIS recurrence or death was recorded, and recurrence-free survival (RFS) was calculated. RESULTS: LncRNA HULC was increased in AIS patients compared to non-AIS controls (P < .001), and receiver operating characteristic curve showed that it was correlated with increased AIS risk (area under curve: 0.876, 95% confidence interval: 0.843-0.908). Meanwhile, lncRNA HULC was positively correlated with NIHSS score (P < .001, r = .456), interleukin-6 (P < .001, r = .275) and ICAM1 (P < .001, r = .383), whereas negatively correlated with miR-9 (P < .001, r = -.438) but not miR-195 (P = .205, r = -.087) in AIS patients. Additionally, miR-9 was negatively correlated with NIHSS score (P < .001, r = -.335), interleukin-6 (P = .001, r = -.231), and ICAM1 (P < .001, r = -.280), while miR-195 was only negatively associated with NIHSS score (P = .041, r = -.139) in AIS patients. Moreover, lncRNA HULC high expression predicted worse RFS (P = .013) in AIS patients. CONCLUSION: LncRNA HULC is correlated with higher AIS risk, increased disease severity and worse prognosis in AIS patients. Meanwhile, it associates with higher IL-6, elevated ICAM1, and lower miR-9 AIS patients.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , ARN Largo no Codificante/sangre , Anciano , Isquemia Encefálica/sangre , Isquemia Encefálica/epidemiología , Isquemia Encefálica/mortalidad , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/sangre , Interleucina-6/sangre , Accidente Cerebrovascular Isquémico/sangre , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/mortalidad , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Recurrencia , Sensibilidad y Especificidad
15.
J Cell Mol Med ; 23(7): 4666-4678, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31033175

RESUMEN

The traditional Chinese herb Lonicerae Japonicae Flos has shown significant clinical benefits in the treatment of heart failure, but the mechanism remains unclear. As the main active ingredient found in the plasma after oral administration of Lonicerae Japonicae Flos, chlorogenic acid (CGA) has been reported to possess anti-inflammatory, anti-oxidant and anti-apoptosis function. We firstly confirmed the cardioprotective effects of CGA in transverse aortic constriction (TAC)-induced heart failure mouse model, through mitigating the TNF-α-induced toxicity. We further used TNF-α-induced cardiac injury in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) to elucidate the underlying mechanisms. CGA pre-treatment could reverse TNF-α-induced cellular injuries, including improved cell viability, increased mitochondrial membrane potential and inhibited cardiomyocytes apoptosis. We then examined the NF-κB/p65 and major mitogen-activated protein kinases (MAPKs) signalling pathways involved in TNF-α-induced apoptosis of hiPSC-CMs. Importantly, CGA can directly inhibit NF-κB signal by suppressing the phosphorylation of NF-κB/p65. As for the MAPKs, CGA suppressed the activity of only c-Jun N-terminal kinase (JNK), but enhanced extracellular signal-regulated kinase1/2 (ERK1/2) and had no effect on p38. In summary, our study revealed that CGA has profound cardioprotective effects through inhibiting the activation of NF-κB and JNK pathway, providing a novel therapeutic alternative for prevention and treatment of heart failure.


Asunto(s)
Ácido Clorogénico/farmacología , Citoprotección/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/toxicidad , Animales , Aorta/patología , Apoptosis/efectos de los fármacos , Cardiotónicos/farmacología , Supervivencia Celular/efectos de los fármacos , Ácido Clorogénico/uso terapéutico , Constricción Patológica , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/tratamiento farmacológico , Células Madre Pluripotentes Inducidas/citología , Masculino , Ratones Endogámicos C57BL , Modelos Biológicos , Miocitos Cardíacos/efectos de los fármacos , Volumen Sistólico/efectos de los fármacos
16.
Molecules ; 24(15)2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31390736

RESUMEN

Four new lignan glycosides; urenalignosides A-D (1-4), along with 12 known ones (5-16) were isolated from Urena lobata. Their structures were determined on the basis of extensive spectroscopic and spectrometric data (1D and 2D NMR; IR; CD; and HRESIMS). Compounds 2-4; 6; 7; 10; and 11 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophage cells with IC50 values in the range of 25.5-98.4 µM (positive control; quercetin; IC50 = 7.2 ± 0.2 µM).


Asunto(s)
Glicósidos/química , Lignanos/química , Malvaceae/química , Extractos Vegetales/química , Animales , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Lignanos/aislamiento & purificación , Lignanos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Células RAW 264.7
17.
J Am Chem Soc ; 140(39): 12354-12358, 2018 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-30235414

RESUMEN

Lateral heterostructures with planar integrity form the basis of two-dimensional (2D) electronics and optoelectronics. Here we report that, through a two-step chemical vapor deposition (CVD) process, high-quality lateral heterostructures can be constructed between metallic and semiconducting transition metal disulfide (TMD) layers. Instead of edge epitaxy, polycrystalline monolayer MoS2 in such junctions was revealed to nucleate from the vertices of multilayered VS2 crystals, creating one-dimensional junctions with ultralow contact resistance (0.5 kΩ·µm). This lateral contact contributes to 6-fold improved field-effect mobility for monolayer MoS2, compared to the conventional on-top nickel contacts. The all-CVD strategy presented here hence opens up a new avenue for all-2D-based synthetic electronics.

18.
Zhongguo Zhong Yao Za Zhi ; 43(18): 3787-3794, 2018 Sep.
Artículo en Zh | MEDLINE | ID: mdl-30384547

RESUMEN

Heat-clearing and detoxifying Chinese herbs (HDCHs) are mainly used to treat carbuncle, sore throat, erysipelas, gills, dysentery and other diseases induced by heat-toxicity. Inflammation is a defensive response to damaging factors in living organism with vascular system. In recent years, a large amount of experimental and clinical studies showed that HDCHs had good therapeutic effect on inflammation. This review analyzed the anti-inflammatory mechanism of 11 HDCHs by retrieving literature in past 5 years, including Lonicerae Japonicae Flos (Jinyinhua), Lonicerae Flos (Jinyinhua), Lonicerae Japonicae Caulis (Rendongteng), Forsythiae Fructus (Lianqiao), Rhizoma Coptidis(Huanglian), Gardeniae Fructus (Zhizi), Andrographis Herba (Chuanxinlian), Taraxaci Herba (Pugongying), Scrophulariae Radix (Xuanshen), Pulsatillae Radix (Baitouweng), and Agrimoniae Herba (Xianhecao). The data showed that the regulatory effect of HDCHs on inflammation may be involved mainly in the nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK) or janus kinase-signal transducers and activators of transcription (JAK-STAT) pathway, with similarity of action links among these three. Based upon the analysis of literature, we proposed some promising directions in this research field, providing a reliable theoretical basis for both experimental researches and clinical practices of HDCHs.


Asunto(s)
Antiinflamatorios/farmacología , Medicamentos Herbarios Chinos/farmacología , Calor , Humanos , Medicina Tradicional China , Transducción de Señal/efectos de los fármacos
19.
J Biol Chem ; 291(51): 26352-26363, 2016 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-27624941

RESUMEN

Huntingtin-associated protein 1 (Hap1) was originally identified as a protein that binds to the Huntington disease protein, huntingtin. Growing evidence has shown that Hap1 participates in intracellular trafficking via its association with various microtubule-dependent transporters and organelles. Recent studies also revealed that Hap1 is involved in exocytosis such as insulin release from pancreatic ß-cells. However, the mechanism underlying the action of Hap1 on insulin release remains to be investigated. We found that Hap1 knock-out mice had a lower plasma basal insulin level than control mice. Using cultured pancreatic ß-cell lines, INS-1 cells, we confirmed that decreasing Hap1 reduces the number of secreted vesicles and inhibits vesicle exocytosis. Electrophysiology and imaging of intracellular Ca2+ measurements demonstrated that Hap1 depletion significantly reduces the influx of Ca2+ mediated by L-type Ca2+ channels (Cav). This decrease is not due to reduced expression of Cav1.2 channel mRNA but results from the decreased distribution of Cav1.2 on the plasma membrane of INS-1 cells. Fluorescence recovery after photobleaching showed a defective movement of Cav1.2 in Hap1 silencing INS-1 cells. Our findings suggest that Hap1 is important for insulin secretion of pancreatic ß-cells via regulating the intracellular trafficking and plasma membrane localization of Cav1.2, providing new insight into the mechanisms that regulate insulin release from pancreatic ß-cells.


Asunto(s)
Canales de Calcio Tipo L/metabolismo , Membrana Celular/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Canales de Calcio Tipo L/genética , Línea Celular Tumoral , Membrana Celular/genética , Insulina/genética , Secreción de Insulina , Células Secretoras de Insulina/citología , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética
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