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1.
Opt Lett ; 49(10): 2685-2688, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748136

RESUMO

Compact light couplers between III-V devices and Si waveguides are crucial for advancing the scalability of Si photonics. Here, we present a compact light coupling strategy for lateral III-V membrane lasers and PDs directly grown on SOI platforms. Benefiting from the coplanar configuration of epitaxial III-V membranes and Si device layer, we designed novel, to our knowledge, butt couplers to achieve both small footprint and high efficiency coupling. We employed sub-wavelength grating structures to gradually bridge the effective refractive index between the III-V membranes and Si waveguide and obtained a coupling loss of less than 0.5 dB across the entire telecom band in a length of less than 10 µm. Our work here offers a fresh perspective for future densely integrated Si photonics.

2.
J Nat Prod ; 83(6): 1766-1777, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32479076

RESUMO

Fourteen new terpenoids plagicosins A-N (1-14), including seven sesquiterpenoids (1-7) consisting of six ent-bicyclogermacrenes and one ent-2,3-seco-aromadendrane, as well as seven diterpenoids (8-14) comprising five fusicoccanes, a eunicellane, and a rare gersemiane, were isolated from the Chinese liverwort Plagiochila fruticosa Mitt. The structures of these terpenoids were determined on the basis of comprehensive analysis of MS and NMR spectroscopic data coupled with electronic circular dichroism (ECD) and coupling constant calculations. Plagicosin F (6) displayed potent antivirulence activity through inhibiting the hyphal morphogenesis, adhesion, and biofilm formation of Candida albicans. The genes related to hyphal formation were regulated by 6.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Hepatófitas/química , Terpenos/farmacologia , Biofilmes/efeitos dos fármacos , Dicroísmo Circular , Diterpenos/química , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Sesquiterpenos/química , Terpenos/química , Virulência/efeitos dos fármacos
3.
Bioorg Med Chem ; 26(9): 2392-2400, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29655613

RESUMO

Five new terpenoids (1-5) including two dollabellane-type, one ent-kaurane-type diterpenoids and two sesquiterpenoids were isolated from the Chinese liverwort Lepidozia reptans (L.) Dumort., together with nine known terpenoids (6-14). Their structures were determined on the basis of analysis of MS and NMR spectroscopic data, single-crystal X-ray diffraction and electronic circular dichroism calculations. The selected compounds 1, 2, 6, 7, 9 and 14 were screened for anti-inflammatory activities by the model of LPS-induced nitric oxide (NO) production with macrophage cells, and the mechanism of the active compounds 1 and 2 were further explored.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Ciclo-Oxigenase 2/metabolismo , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/isolamento & purificação , Hepatófitas/química , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Células RAW 264.7/metabolismo , RNA Mensageiro/genética , Sesquiterpenos/síntese química , Sesquiterpenos/isolamento & purificação , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
4.
Mitochondrial DNA B Resour ; 7(4): 683-685, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35478861

RESUMO

Plastid genomes are useful markers in resolving plant phylogenetic relationships for various taxonomic groups. Here, we sequenced and de novo assembled the complete plastid genome sequence of an Antarctic moss Chorisodontium aciphyllum (Hook. f. & Wilson) Broth using genome skimming data. The newly generated plastid genome is conserved in structure and gene content compared with that of other Bryopsida. Plastid phylogenetic analysis of mosses recovered a robust phylogeny in which Chorisodontium aciphyllum clustered with Fissidens nobilis from the Dicranales. The plastid genome sequence of C. aciphyllum will aid future evolution and diversification studies of land plants.

5.
Phytochemistry ; 158: 77-85, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30476899

RESUMO

Six previously undescribed labdane diterpenoids, frullanians A-F, along with five known diterpenoids, were isolated from the Chinese liverwort Frullania hamatiloba Stephani. Their structures were determined using NMR data, electronic circular dichroism (ECD) calculations as well as the single crystal X-ray diffraction measurement. NAD(P)H: QR (quinone reductase) assay demonstrated that frullanian D and four known compounds displayed antioxidant effect mediated via Nrf2 (Nuclear factor-erythroid 2-related factor 2) induction. Further investigation of the most bioactive frullanian D in MOVAS cells revealed that it ameliorated H2O2-induced oxidative insults without toxicity by increasing cell viability, attenuating morphological changes, and reducing intracellular ROS production. In addition, frullanian D promoted the nuclear translocation of Nrf2 and upregulated the expressions of antioxidant proteins NQO1 (NAD(P)H quinone oxidoreductase 1) and γ-GCS (γ-glutamyl cysteine synthetase). Docking analysis using MOE software further supported the activation of the Nrf2 pathway by frullanian D.


Assuntos
Antioxidantes/farmacologia , Diterpenos/farmacologia , Frullania/química , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Linhagem Celular , Dicroísmo Circular , Cristalografia por Raios X , Diterpenos/administração & dosagem , Diterpenos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Peróxido de Hidrogênio/toxicidade , Espectroscopia de Ressonância Magnética , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
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