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1.
Opt Lett ; 49(19): 5579-5582, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39353011

RESUMEN

Integrated power dividers (PDs) are essential in terahertz (THz) communication and radar systems, but miniaturization often leads to performance degradation due to fabrication inaccuracies and sharp bends. Topological photonics offers a solution to these issues, yet creating THz power dividers with arbitrary splitting ratios remains challenging. We present a design methodology for on-chip topological THz power dividers with customizable splitting ratios using valley-locked photonic crystals. These crystals feature a tri-layered structure with two distinct valley Chern number layers and an intermediate semimetal layer. Utilizing the Jackiw-Rebbi model, we show that the characteristic impedance of the valley-locked photonic crystals, and thus the power division ratio, can be tuned by adjusting the semimetal layer width. Our approach is validated through simulations and experiments for both equal (1:1) and unequal (4:9) power ratios. This method enables efficient navigation around sharp bends and robust THz on-chip connectivity.

2.
Phytomedicine ; 135: 156031, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39305745

RESUMEN

BACKGROUND: Previous research demonstrated the effects of Sorbaria sorbifolia (SS) in combating hepatocellular carcinoma (HCC). Despite SS's proven efficacy in treating HCC, the precise bioactive constituents contributing to its therapeutic benefits, along with the mechanisms behind them, warrant further exploration. PURPOSE: The objective of our study was to illuminate the possible elements, targets, and modulatory pathways employed by specific bioactive components in SS for HCC treatment. STUDY DESIGN: Using UPLC-Q-TOF-MS to analyze and quantify the bioactive constituents in the SS sample. By literature review, we gathered potential chemical constituents of SS. We used network pharmacology approaches to identify HCC-related targets of SS components, with an emphasis on core targets. To examine the core targets' importance in HCC biological processes, bioinformatics methods were utilized. Finally, molecular docking, MD simulations, and CESTA were employed to screen SS active ingredients capable of stably binding with core targets. To verify the anti-HCC effectiveness of these active components, we conducted several cellular experiments, including CCK8, wound healing, transwell, cell cycle, and apoptosis assays, as well as animal experiments like zebrafish HepG2 cell xenotransplantation, apoptosis assays, and HE staining. We also used lentivirus transfection to modulate core protein expression in HepG2 cells, creating cell models. Further cellular tests were performed to evaluate the ability of SS active ingredients to exert anti-HCC effects by interacting with the core protein to induce apoptosis. Finally, Western Blot and ELISA experiments were carried out to track changes in core protein and apoptosis-related pathway proteins after SS active ingredient treatment RESULTS: Our study identified 50 components in SS and 119 HCC-related target genes, with DHRS13 emerging as a core target. Further bioinformatics analysis indicated that DHRS13 expression in HCC patients correlated with prognosis and apoptotic pathways. Molecular docking revealed 20 active SS constituents effectively binding to DHRS13, MD simulations and CESTA pinpointed Quercetin 7-rhamnoside (Q7R) as the most stable binder. In-vitro and in-vivo tests verified Q7R's anti-HCC properties. Lentivirus transfection results showed that knockdown DHRS13 led to reduced cell growth and increased apoptosis, while overexpression DHRS13 led to increase cell growth and decrease apoptosis. Remarkably, our experiments found that Q7R acts as an inhibitor of DHRS13 and can reverse the suppressed apoptosis and excessive HCC proliferation caused by DHRS13 overexpression. CONCLUSION: Elevated DHRS13 expression contributes to HCC progression. Q7R effectively downregulates DHRS13, encouraging apoptosis and impeding HCC growth. As a result, Q7R shows potential as a therapeutic agent for HCC treatment, targeting the apoptotic pathway through DHRS13 regulation.

3.
Proc Natl Acad Sci U S A ; 121(6): e2309096120, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38285934

RESUMEN

Invisibility, a fascinating ability of hiding objects within environments, has attracted broad interest for a long time. However, current invisibility technologies are still restricted to stationary environments and narrow band. Here, we experimentally demonstrate a Chimera metasurface for multiterrain invisibility by synthesizing the natural camouflage traits of various poikilotherms. The metasurface achieves chameleon-like broadband in situ tunable microwave reflection mimicry of realistic water surface, shoal, beach/desert, grassland, and frozen ground from 8 to 12 GHz freely via the circuit-topology-transited mode evolution, while remaining optically transparent as an invisible glass frog. Additionally, the mechanic-driven Chimera metasurface without active electrothermal effect, owning a bearded dragon-like thermal acclimation, can decrease the maximum thermal imaging difference to 3.1 °C in tested realistic terrains, which cannot be recognized by human eyes. Our work transitions camouflage technologies from the constrained scenario to ever-changing terrains and constitutes a big advance toward the new-generation reconfigurable electromagnetics with circuit-topology dynamics.

4.
J Ethnopharmacol ; 324: 117758, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38246481

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Sorbaria sorbifolia (SS) is a traditional Chinese medicine (TCM) that has been employed anti-hepatocellular carcinoma (HCC) for over 2000 years; yet, its underlying mechanism is still not fully understood. AIM OF THE STUDY: In this study, we evaluated the anti-HCC effect on the freeze-dried powder of the water extract of SS (FDSS) by inhibiting tumor-induced neovascularization, and promoting apoptosis, and elucidated the underlying mechanisms. MATERIALS AND METHODS: HCC cell lines (HepG2 and Huh7 cells) and HepG2 xenograft tumors in zebrafish were employed as in vivo and in vitro models, respectively, to evaluate the anti- HCC-indued neovascularization and apoptosis. In HCC cell lines, CCK-8 assay, wound-healing assay, transwell assay, cell circle assay, apoptosis assay, transmission electron microscopy, and co-culture assay were performed in vitro; in HepG2 xenograft tumor-zebrafish, tumor growth inhibition assay, hematoxylin and eosin (HE) staining, xenograft tumor-zebrafish apoptosis assay, and HCC-indued neovascularization assay were performed to evaluate the effect of FDSS on biological behavior of tumor, HCC-indued neovascularization, and apoptosis. The expression of VEGFR and c-Met/apoptotic pathway-related proteins was detected by western blotting analysis. Assays for c-Met and VEGFR activation were conducted to assess the impact of FDSS in either agonistic or inhibitory roles on these receptor proteins. RESULTS: The findings from our study revealed that FDSS effectively suppresses the proliferation, migration, and invasion of HepG2 and Huh7 cells, as well as inhibiting tumor growth in the HepG2 xenograft zebrafish model by downregulating the expression of p-Met and p-AKT proteins. FDSS decreased the tumor growth associated with promoting apoptosis, including arresting HepG2 and Huh7 cells cycle at G0/G1phase, increasing apoptotic cell numbers and apoptotic bodies in cancer cells, and increasing the apoptotic fluorescence of xenograft tumor zebrafish by downregulating Bcl-2 proteins and upregulating Bax, caspase-9, and caspase-3 levels. We also found that FDSS can inhibit HCC-induced neovascularization and regulate VEGFR. Using an agonist or inhibitor of c-Met and VEGFR in HepG2 cells, we discovered that FDSS can downregulate c-Met and VEGFR protein expression. CONCLUSION: FDSS exerts an anti-HCC effect by inhibiting HCC-indued neovascularization and pro-apoptosis through the inhibition of the action of VEGFR and c-Met/apoptotic pathway.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Pez Cebra , Antineoplásicos/farmacología , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Reguladoras de la Apoptosis , Apoptosis , Proliferación Celular
5.
J Colloid Interface Sci ; 465: 42-6, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26641563

RESUMEN

In this work, we present a novel approach on the simultaneous enhancement of intensity of red, green, and blue (RGB) emission by heterostructure colloidal photonic crystals (PCs) with tri-stopbands. The intensity of RGB emission on heterostructure PCs with tri-stopbands overlapping emission wavelengths of RGB QDs can be up to about 8-fold enhancement in comparison to that on the control sample. Furthermore, CIE diagrams show the chromaticity parameters approaching that of white light. The method will be favorable for developing optical devices of high performance.

6.
ACS Appl Mater Interfaces ; 7(19): 10563-75, 2015 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-25954980

RESUMEN

Composite thermoplastic elastomers (CTPEs) of magnetic copolymer-grafted nanoparticles (magnetite, Fe3O4) were synthesized and characterized to generate magnetic CTPEs, which combined the magnetic property of Fe3O4 nanoparticles and the thermoplastic elasticity of the grafted amorphous polymer matrix. Fe3O4 nanoparticles served as stiff, multiple physical cross-linking points homogeneously dispersed in the grafted poly(n-butyl acrylate-co-methyl methacrylate) rubbery matrix synthesized via the activators regenerated by electron transfer for atom transfer radical polymerization method (ARGET ATRP). The preparation technique for magnetic CTPEs opened a new route toward developing a wide spectrum of magnetic elastomeric materials with strongly enhanced macroscopic properties. Differential scanning calorimetry (DSC) was used to measure the glass transition temperatures, and thermogravimetric analysis (TGA) was used to examine thermal stabilities of these CTPEs. The magnetic property could be conveniently tuned by adjusting the content of Fe3O4 nanoparticles in CTPEs. Compared to their linear copolymers, these magnetic CTPEs showed significant increases in tensile strength and elastic recovery. In situ small-angle X-ray scattering measurement was conducted to reveal the microstructural evolution of CTPEs during tensile deformation.

7.
ACS Appl Mater Interfaces ; 3(12): 4858-64, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22103556

RESUMEN

Composites consisting of polylactide (PLA) and poly(ε-caprolactone) (PCL) filled with acid-oxidized multiwalled carbon nanotubes (A-MWCNTs) were prepared through melt compounding. Phase morphologies of PLA/PCL/A-MWCNT composites with different contents of filled A-MWCNTs and PCL compositions were mainly observed by scanning electron microscope. The results show that A-MWCNTs are selectively dispersed in the PCL phase, regardingless of PCL phase domain sizes. For PLA/PCL/A-MWCNT composites with fixed PLA/PCL ratio of 95/5, the dispersed PCL phase domain sizes in the PLA matrix decrease even though a small content of A-MWCNTs is added, compared with PLA/PCL blend with the same composition, indicating that A-MWCNTs effectively prevent from coalescence of the dispersed PCL phase domains. With filling of 1.0 wt % A-MWCNTs, an interesting change of electrical conductivity for PLA/PCL/A-MWCNT composites is observed, in which the maximum conductivity is observed for PLA/PCL/A-MWCNT composite with PLA/PCL ratio of 60/40. The result is well-explained by the formed cocontinuous phase morphology and effective A-MWCNT content.

8.
ACS Appl Mater Interfaces ; 3(9): 3744-53, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21859160

RESUMEN

Biodegradable polylactide (PLA) composites added with acid oxidized multiwalled carbon nanotubes (A-MWCNTs) of two different aspect ratios (length to diameter) were prepared by coagulation. The aspect ratios and surface structures of A-MWCNTs were characterized by TGA, Raman, and SEM measurements. The percolation thresholds for gelation in the PLA composites with A-MWCNTs of large and small aspect ratios are 2.5 and 4.0 wt %, respectively, which were determined by a rheological method, and in turn, the rheological result confirms the aspect ratio differences for the added two types of A-MWCNTs in the composites. Isothermal crystallization kinetics of neat PLA and its composites were further investigated by using polarized optical microscope (POM) and differential scanning calorimetry (DSC) to clarify the effects of A-MWCNTs of different aspect ratios and concentrations. The different aspect ratio A-MWCNTs with the same carboxyl group mass percent show substantial effects on PLA crystallization kinetics. Those with smaller aspect ratios enhance nucleation rate for PLA spherulites much more than those with larger aspect ratios. This phenomenon can be attributed to fewer sidewall carboxyl groups on the surfaces of A-MWCNTs with smaller aspect ratios, which provides more nucleation sites for PLA crystallization than those with larger aspect ratios at the same concentration, resulting in faster PLA nucleation rates for the former one.


Asunto(s)
Nanotubos de Carbono/química , Poliésteres/química , Rastreo Diferencial de Calorimetría , Cristalización , Nanotubos de Carbono/ultraestructura , Oxidación-Reducción , Espectrometría Raman , Propiedades de Superficie , Termogravimetría
9.
J Genet Genomics ; 36(7): 435-42, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19631918

RESUMEN

It is generally accepted that Oryza rufipogon is the progenitor of Asian cultivated rice (O. sativa). However, how the two subspecies of O. sativa (indica and japonica) were domesticated has long been debated. To investigate the genetic differentiation in O. rufipogon in relation to the domestication of O. sativa, we developed 57 subspecies-specific intron length polymorphism (SSILP) markers by comparison between 10 indica cultivars and 10 japonica cultivars and defined a standard indica rice and a standard japonica rice based on these SSILP markers. Using these SSILP markers to genotype 73 O. rufipogon accessions, we found that the indica alleles and japonica alleles of the SSILP markers were predominant in the O. rufipogon accessions, suggesting that SSILPs were highly conserved during the evolution of O. sativa. Cluster analysis based on these markers yielded a dendrogram consisting of two distinct groups: one group (Group I) comprises all the O. rufipogon accesions from tropical (South and Southeast) Asia as well as the standard indica rice; the other group (Group II) comprises all the O. rufipogon accessions from Southern China as well as the standard japonica rice. Further analysis showed that the two groups have significantly higher frequencies of indica alleles and japonica alleles, respectively. These results support the hypothesis that indica rice and japonica rice were domesticated from the O. rufipogon of tropical Asia and from that of Southern China, respectively, and suggest that the indica-japonica differentiation should have formed in O. rufipogon long before the beginning of domestication. Furthermore, with an O. glaberrima accession as an outgroup, it is suggested that the indica-japonica differentiation in O. rufipogon might occur after its speciation from other AA-genome species.


Asunto(s)
Productos Agrícolas/genética , Intrones , Oryza/genética , Polimorfismo Genético , Alelos , Marcadores Genéticos
10.
Fungal Genet Biol ; 45(10): 1340-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18694839

RESUMEN

Magnaporthe grisea is the most destructive fungal pathogen of rice and a model organism for studying plant-pathogen interaction. Molecular markers and genetic maps are useful tools for genetic studies. In this study, based on the released genome sequence data of M. grisea, we investigated 446 simple sequence repeat (SSR) loci and developed 313 SSR markers, which showed polymorphisms among nine isolates from rice (including a laboratory strain 2539). The number of alleles of each marker ranged 2-9 with an average of 3.3. The polymorphic information content (PIC) of each marker ranged 0.20-0.89 with an average of 0.53. Using a population derived from a cross between isolates Guy11 and 2539, we constructed a genetic map of M. grisea consisting of 176 SSR markers. The map covers a total length of 1247 cM, equivalent to a physical length of about 35.0 Mb or 93% of the genome, with an average distance of 7.1cM between adjacent markers. A web-based database of the SSR markers and the genetic map was established (http://ibi.zju.edu.cn/pgl/MGM/index.html).


Asunto(s)
Magnaporthe/genética , Repeticiones de Microsatélite , Oryza/microbiología , Mapeo Físico de Cromosoma , Enfermedades de las Plantas/microbiología , Bases de Datos Genéticas , Ligamiento Genético , Polimorfismo Genético
11.
Bioinformatics ; 23(16): 2174-7, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17545179

RESUMEN

MOTIVATION: With the recent progress made in large-scale plant functional genome sequencing projects, a great amount of EST (express sequence tag) data is becoming available. With the help of complete genomic sequence information of model plants (rice and Arabidopsis), it is possible to predict the joints between adjacent exons after splicing (or termed 'intron positions' for short) in homologous ESTs of other plants. This would allow developing potential intron polymorphism (PIP) markers in these plants by designing primers in exons flanking the target intron. RESULTS: We have extracted a total of 57,658 PIP markers in 59 plant species and created a web-based database platform named PIP to provide detailed information of these PIP markers and homologous relationships among PIP markers from different species. The platform also provides a function of online designing of PIP markers based on cDNA/EST sequences submitted by users. With evaluations performed in silico, we have found that the intron position prediction is highly reliable and the polymorphism level of PIP markers is high enough for practical need. AVAILABILITY: http://ibi.zju.edu.cn/pgl/pip/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Mapeo Cromosómico/métodos , ADN de Plantas/genética , Bases de Datos Genéticas , Marcadores Genéticos/genética , Genoma de Planta/genética , Intrones/genética , Polimorfismo de Nucleótido Simple/genética , Secuencia de Bases , Evolución Molecular , Variación Genética/genética , Almacenamiento y Recuperación de la Información/métodos , Datos de Secuencia Molecular
12.
Chin J Traumatol ; 8(6): 383-4, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16313718

RESUMEN

As an emergency, a foreign body in the heart should generally be removed as early as possible by surgical or non-surgical procedures in order to avoid any complications. Early treatment typically results in a better prognosis.

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