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1.
PLoS Genet ; 18(10): e1010433, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36301831

RESUMO

Circular RNAs (circRNAs) are a new group of noncoding/regulatory RNAs that are particularly abundant in the nervous system, however, their physiological functions are underexplored. Here we report that the brain-enriched circular RNA Edis (Ect4-derived immune suppressor) plays an essential role in neuronal development in Drosophila. We show that depletion of Edis in vivo causes defects in axonal projection patterns of mushroom body (MB) neurons in the brain, as well as impaired locomotor activity and shortened lifespan of adult flies. In addition, we find that the castor gene, which encodes a transcription factor involved in neurodevelopment, is upregulated in Edis knockdown neurons. Notably, castor overexpression phenocopies Edis knockdown, and reducing castor levels suppresses the neurodevelopmental phenotypes in Edis-depleted neurons. Furthermore, chromatin immunoprecipitation analysis reveals that the transcription factor Relish, which plays a key role in regulating innate immunity signaling, occupies a pair of sites at the castor promoter, and that both sites are required for optimal castor gene activation by either immune challenge or Edis depletion. Lastly, Relish mutation and/or depletion can rescue both the castor gene hyperactivation phenotype and neuronal defects in Edis knockdown animals. We conclude that the circular RNA Edis acts through Relish and castor to regulate neuronal development.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , RNA Circular/genética , Proteínas de Drosophila/genética , Fatores de Transcrição/genética , Corpos Pedunculados , Drosophila melanogaster/fisiologia
2.
PLoS Genet ; 18(10): e1010429, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36301822

RESUMO

Circular RNAs (circRNAs) are widely expressed in eukaryotes. However, only a subset has been functionally characterized. We identify and validate a collection of circRNAs in Drosophila, and show that depletion of the brain-enriched circRNA Edis (circ_Ect4) causes hyperactivation of antibacterial innate immunity both in cultured cells and in vivo. Notably, Edis depleted flies display heightened resistance to bacterial infection and enhanced pathogen clearance. Conversely, ectopic Edis expression blocks innate immunity signaling. In addition, inactivation of Edis in vivo leads to impaired locomotor activity and shortened lifespan. Remarkably, these phenotypes can be recapitulated with neuron-specific depletion of Edis, accompanied by defective neurodevelopment. Furthermore, inactivation of Relish suppresses the innate immunity hyperactivation phenotype in the fly brain. Moreover, we provide evidence that Edis encodes a functional protein that associates with and compromises the processing and activation of the immune transcription factor Relish. Importantly, restoring Edis expression or ectopic expression of Edis-encoded protein suppresses both innate immunity and neurodevelopment phenotypes elicited by Edis depletion. Thus, our study establishes Edis as a key regulator of neurodevelopment and innate immunity.


Assuntos
Imunidade Inata , RNA Circular , Animais , RNA Circular/genética , Imunidade Inata/genética , Fatores de Transcrição/genética , Drosophila/genética , Drosophila/metabolismo , Transdução de Sinais , RNA/genética
3.
J Am Chem Soc ; 146(5): 3449-3457, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38268407

RESUMO

The core features of covalent organic frameworks (COFs) are crystallinity and porosity. However, the synthesis of single-crystal COFs with monomers of diverse reactivity and adjustment of their pore structures remain challenging. Here, we show that linkers that can react with a node to form single-crystal COFs can guide other linkers that form either COFs or amorphous polymers with the node to gain single-crystal COFs with mixed components, which are homogeneous on the unit cell scale with controlled ratios. With the linker-guided crystal growth method, we created nine types of single-crystal COFs with up to nine different components, which are more complex than any known crystal. The structure of the crystal adapted approximately to that of the main component, and its pore volume could be expanded up to 8.8%. Different components lead to complex and diverse pore structures and offer the possibilities to gain positive synergies, as exemplified by a bicomponent COF with 2200 and 733% SO2 uptake capacity of that of the two pure-component counterparts at 298 K and 0.002 bar. The selectivity for separation of SO2/CO2 ranges from 1230 to 4247 for flue gas based on ideal adsorbed solution theory, recording porous crystals. The bicomponent COF also exhibits a 1300% retention time of its pure-component counterparts for SO2 in a dynamic column breakthrough experiment for deep desulfurization.

4.
Gastroenterology ; 165(4): 932-945.e9, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37399999

RESUMO

BACKGROUND & AIMS: Early detection of esophageal squamous cell carcinoma (ESCC) will facilitate curative treatment. We aimed to establish a microRNA (miRNA) signature derived from salivary extracellular vesicles and particles (EVPs) for early ESCC detection and prognostication. METHODS: Salivary EVP miRNA expression was profiled in a pilot cohort (n = 54) using microarray. Area under the receiver operator characteristic curve (AUROC) and least absolute shrinkage and selector operation regression analyses were used to prioritize miRNAs that discriminated patients with ESCC from controls. Using quantitative reverse transcription polymerase chain reaction, the candidates were measured in a discovery cohort (n = 72) and cell lines. The prediction models for the biomarkers were derived from a training cohort (n = 342) and validated in an internal cohort (n = 207) and an external cohort (n = 226). RESULTS: The microarray analysis identified 7 miRNAs for distinguishing patients with ESCC from control subjects. Because 1 was not always detectable in the discovery cohort and cell lines, the other 6 miRNAs formed a panel. A signature of this panel accurately identified patients with all-stage ESCC in the training cohort (AUROC = 0.968) and was successfully validated in 2 independent cohorts. Importantly, this signature could distinguish patients with early-stage (stage Ⅰ/Ⅱ) ESCC from control subjects in the training cohort (AUROC = 0.969, sensitivity = 92.00%, specificity = 89.17%) and internal (sensitivity = 90.32%, specificity = 91.04%) and external (sensitivity = 91.07%, specificity = 88.06%) validation cohorts. Moreover, a prognostic signature based on the panel was established and efficiently predicted the high-risk cases with poor progression-free survival and overall survival. CONCLUSIONS: The salivary EVP-based 6-miRNA signature can serve as noninvasive biomarkers for early detection and risk stratification of ESCC. Chinese Clinical Trial Registry, ChiCTR2000031507.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Humanos , Biomarcadores Tumorais/genética , Detecção Precoce de Câncer , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Prognóstico , Curva ROC
5.
Anal Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946253

RESUMO

The determination of pH values is crucial in various fields, such as analytical chemistry, medical diagnostics, and biochemical research. pH test strips, renowned for their convenience and cost-effectiveness, are commonly utilized for pH qualitative estimation. Recently, quantitative methods for determining pH values using pH test strips have been developed. However, these methods can be prone to errors due to environmental factors, such as lighting conditions, which affect the imaging quality of the pH test strips. To address these challenges, we developed an innovative approach that combines machine learning techniques with pH test strips for the quantitative determination of pH values. Our method involves extracting artificial features from the pH test strip images and combining them across multiple dimensions for comprehensive analysis. To ensure optimal feature selection, we developed a feature selection strategy based on SHAP importance. This strategy helps in identifying the most relevant features that contribute to accurate pH prediction. Furthermore, we integrated multiple machine learning algorithms, employing a robust stacking fusion strategy to establish a highly reliable pH value prediction model. Our proposed method automates the determination of pH values through pH test strips, effectively overcoming the limitations associated with environmental lighting interference. Experimental results demonstrate that this method is convenient, effective, and highly reliable for the determination of pH values.

6.
Plant Biotechnol J ; 22(1): 116-130, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37752622

RESUMO

Arabidopsis RESISTANCE TO POWDERY MILDEW 8.1 (RPW8.1) is an important tool for engineering broad-spectrum disease resistance against multiple pathogens. Ectopic expression of RPW8.1 leads to enhanced disease resistance with cell death at leaves and compromised plant growth, implying a regulatory mechanism balancing RPW8.1-mediated resistance and growth. Here, we show that RPW8.1 constitutively enhances the expression of transcription factor WRKY51 and activates salicylic acid and ethylene signalling pathways; WRKY51 in turn suppresses RPW8.1 expression, forming a feedback regulation loop. RPW8.1 and WRKY51 are both induced by pathogen infection and pathogen-/microbe-associated molecular patterns. In ectopic expression of RPW8.1 background (R1Y4), overexpression of WRKY51 not only rescues the growth suppression and cell death caused by RPW8.1, but also suppresses RPW8.1-mediated broad-spectrum disease resistance and pattern-triggered immunity. Mechanistically, WRKY51 directly binds to and represses RPW8.1 promoter, thus limiting the expression amplitude of RPW8.1. Moreover, WRKY6, WRKY28 and WRKY41 play a role redundant to WRKY51 in the suppression of RPW8.1 expression and are constitutively upregulated in R1Y4 plants with WRKY51 being knocked out (wrky51 R1Y4) plants. Notably, WRKY51 has no significant effects on disease resistance or plant growth in wild type without RPW8.1, indicating a specific role in RPW8.1-mediated disease resistance. Altogether, our results reveal a regulatory circuit controlling the accumulation of RPW8.1 to an appropriate level to precisely balance growth and disease resistance during pathogen invasion.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Resistência à Doença/genética , Retroalimentação , Arabidopsis/metabolismo , Morte Celular , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas/genética
7.
Phys Rev Lett ; 132(22): 223801, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38877932

RESUMO

Hybrid microresonators have served an intriguing platform for fundamental research and applied photonics. Here, we study the plasmonics-engineered coupling between degenerate optical whispering gallery modes, which can be tuned in a complex space featuring the dissipative strong, dispersive strong, and weak coupling regimes. Experimentally, the engineering of a single plasmonic resonance to a cavity mode family is examined in a waveguide-integrated high-Q microdisk, from which the complex coupling coefficients are extracted and agree well with theoretical predictions. The coupling strength over 10 GHz is achieved for both dissipative and dispersive interactions, showing a remarkable enhancement compared to that induced by a dielectric scatterer. Furthermore, the far fields of hybridized cavity modes are measured, revealing the coherent interference between the radiative channels. Our results shed light on the engineering of whispering gallery modes through plasmonic resonances, and provide fundamental guidance to practical microcavity devices.

8.
J Nutr ; 154(3): 940-948, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38215939

RESUMO

BACKGROUND: Gangliosides are crucial for early-life cognition and immunity development. However, limited data exist on gangliosides within the Chinese population, and maternal-to-fetal/infant ganglioside transport remains unclear. OBJECTIVES: This study aimed to investigate gangliosides concentrations and trajectories in Chinese human milk during the first 400 d of lactation, and seek to understand gangliosides transmission between mother and offspring. METHODS: This study involved 921 cross-sectional participants providing human milk samples across 0-400 d of lactation and 136 longitudinal participants offering maternal plasma, cord plasma, and human milk samples within the first 45 d postpartum. Ultrahigh-performance liquid chromatography-tandem mass spectrometry was used for the quantification of gangliosides. RESULTS: Human milk GM3 (Neu5Acα2-3Galß1-4GlcßCer) concentration increased from 2.29 ± 1.87 to 13.93 ± 4.82 µg/mL, whereas GD3 (Neu5Acα2-8Neu5Acα2-3Galß1-4GlcßCer) decreased from 17.94 ± 6.41 to 0.30 ± 0.50 µg/mL during the first 400 d postpartum (all P < 0.05). Consistent results were observed in cross-sectional and longitudinal participants. GD3 concentration gradually increased from maternal plasma (1.58 µg/mL) through cord plasma (2.05 µg/mL) to colostrum (21.35 µg/mL). Significant positive correlations were observed between maternal and cord plasma for both GM3 (r = 0.30, P < 0.001) and GD3 (r = 0.35, P < 0.001), and maternal plasma GD3 also correlated positively with colostrum concentrations (r = 0.21, P = 0.015). Additionally, in maternal and cord plasma, gangliosides were mainly linked with 16- and 18-carbon fatty acids. However, human milk GM3 showed a broad spectrum of fatty acid chain lengths, whereas GD3 was primarily tied to very long-chain fatty acids (≥20 carbon). CONCLUSIONS: We identified an increase in GM3 and a decrease in GD3 concentration in human milk, with GD3 notably more concentrated in cord plasma and colostrum. Importantly, ganglioside concentrations in maternal plasma positively correlated with those in cord plasma and colostrum. Our findings contribute to the existing Chinese data on gangliosides and enhance understanding of their transmission patterns from mother to offspring. This trial was registered at chictr.org.cn as ChiCTR1800015387.


Assuntos
Gangliosídeos , Leite Humano , Gravidez , Feminino , Humanos , Leite Humano/química , Gangliosídeos/análise , Estudos de Coortes , Estudos Transversais , Ácidos Graxos , Carbono , China
9.
Bioorg Chem ; 143: 107005, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043397

RESUMO

Uveal melanoma (UM) represents the predominant ocular malignancy among adults, exhibiting high malignancy and proclivity for liver metastasis. GNAQ and GNA11 encoding Gαq and Gα11 proteins are key genes to drive UM, making the selective inhibition of Gαq/11 proteins to be a potential therapeutic approach for combating UM. In this study, forty-six quinazoline derivatives were designed, synthesized, and assessed for their ability to inhibit Gαq/11 proteins and UM cells. Compound F33 emerged as the most favorable candidate, and displayed moderate inhibitory activity against Gαq/11 proteins (IC50 = 9.4 µM) and two UM cell lines MP41 (IC50 = 6.7 µM) and 92.1 (IC50 = 3.7 µM). Being a small molecule inhibitor of Gαq/11 proteins, F33 could effectively suppress the activation of downstream signaling pathways in a dose-dependent manner, and significantly inhibits UM in vitro.F33 represents a promising lead compound for developing therapeutics for UM by targeting Gαq/11 proteins.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Melanoma/patologia , Transdução de Sinais , Neoplasias Uveais/tratamento farmacológico , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismo , Linhagem Celular Tumoral
10.
Acta Pharmacol Sin ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902502

RESUMO

The vasopressin V2 receptor (V2R) is a validated therapeutic target for autosomal dominant polycystic kidney disease (ADPKD), with tolvaptan being the first FDA-approved antagonist. Herein, we used Gaussian accelerated molecular dynamics simulations to investigate the spontaneous binding of tolvaptan to both active and inactive V2R conformations at the atomic-level. Overall, the binding process consists of two stages. Tolvaptan binds initially to extracellular loops 2 and 3 (ECL2/3) before overcoming an energy barrier to enter the pocket. Our simulations result highlighted key residues (e.g., R181, Y205, F287, F178) involved in this process, which were experimentally confirmed by site-directed mutagenesis. This work provides structural insights into tolvaptan-V2R interactions, potentially aiding the design of novel antagonists for V2R and other G protein-coupled receptors.

11.
Acta Pharmacol Sin ; 45(1): 166-179, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37605050

RESUMO

Dry eye disease (DED) is a prevalent ocular disorder with a multifactorial etiology. The pre-angiogenic and pre-inflammatory milieu of the ocular surface plays a critical role in its pathogenesis. DZ2002 is a reversible type III S-adenosyl-L-homocysteine hydrolase (SAHH) inhibitor, which has shown excellent anti-inflammatory and immunosuppressive activities in vivo and in vitro. In this study, we evaluated the therapeutic potential of DZ2002 in rodent models of DED. SCOP-induced dry eye models were established in female rats and mice, while BAC-induced dry eye model was established in female rats. DZ2002 was administered as eye drops (0.25%, 1%) four times daily (20 µL per eye) for 7 or 14 consecutive days. We showed that topical application of DZ2002 concentration-dependently reduced corneal neovascularization and corneal opacity, as well as alleviated conjunctival irritation in both DED models. Furthermore, we observed that DZ2002 treatment decreased the expression of genes associated with angiogenesis and the levels of inflammation in the cornea and conjunctiva. Moreover, DZ2002 treatment in the BAC-induced DED model abolished the activation of the STAT3-PI3K-Akt-NF-κB pathways in corneal tissues. We also found that DZ2002 significantly inhibited the proliferation, migration, and tube formation of human umbilical endothelial cells (HUVECs) while downregulating the activation of the STAT3-PI3K-Akt-NF-κB pathway. These results suggest that DZ2002 exerts a therapeutic effect on corneal angiogenesis in DED, potentially by preventing the upregulation of the STAT3-PI3K-Akt-NF-κB pathways. Collectively, DZ2002 is a promising candidate for ophthalmic therapy, particularly in treating DED.


Assuntos
Neovascularização da Córnea , Síndromes do Olho Seco , Ratos , Humanos , Camundongos , Animais , Feminino , Neovascularização da Córnea/tratamento farmacológico , Neovascularização da Córnea/metabolismo , Neovascularização da Córnea/patologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Roedores/metabolismo , Células Endoteliais/metabolismo , Angiogênese , Inflamação/tratamento farmacológico , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/induzido quimicamente , Fator de Transcrição STAT3/metabolismo
12.
J Am Chem Soc ; 145(26): 14354-14364, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37348117

RESUMO

Deep SO2 removal and recovery as industrial feedstock are of importance in flue-gas desulfurization and natural-gas purification, yet developing low-cost and scalable physisorbents with high efficiency and recyclability remains a challenge. Herein, we develop a viable synthetic protocol to produce DUT-67 with a controllable MOF structure, excellent crystallinity, adjustable shape/size, milli-to-kilogram scale, and consecutive production by recycling the solvent/modulator. Furthermore, simple HCl post-treatment affords depurated DUT-67-HCl featuring ultrahigh purity, excellent chemical stability, fully reversible SO2 uptake, high separation selectivity (SO2/CO2 and SO2/N2), greatly enhanced SO2 capture capacity, and good reusability. The SO2 binding mechanism has been elucidated by in situ X-ray diffraction/infrared spectroscopy and DFT/GCMC calculations. The single-step SO2 separation from a real quaternary N2/CO2/O2/SO2 flue gas containing trace SO2 is implementable under dry and 50% humid conditions, thus recovering 96% purity. This work may pave the way for future SO2 capture-and-recovery technology by pushing MOF syntheses toward economic cost, scale-up production, and improved physiochemical properties.

13.
Gastroenterology ; 163(4): 1024-1037.e9, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35788345

RESUMO

BACKGROUND & AIMS: Studies have reported abnormal gut microbiota or circulating metabolome associated with colorectal cancer (CRC), but it remains a challenge to capture the CRC-relevant features consistent across geographic regions. This is particularly the problem for metabolic traits of CRC because the analyses generally use different platforms and laboratory methods, which poses a barrier to cross-dataset examination. In light of this, we sought to elucidate the microbial and metabolic signatures of CRC with broad population relevance. METHODS: In this integrated metagenomic (healthy controls [HC], n = 91; colorectal adenoma [CRA], n = 63; CRC, n = 71) and metabolomic (HC, n = 34; CRA, n = 31; CRC, n = 35) analysis, CRC-associated features and microbe-metabolite correlations were first identified from a Shanghai cohort. A gut microbial panel was trained in the in-house cohort and cross-validated in 7 published metagenomic datasets of CRC. The in-house metabolic connections to the cross-cohort microbial signatures were used as evidence to infer serum metabolites with potentially external relevance. In addition, a combined microbe-metabolite panel was produced for diagnosing CRC or adenoma. RESULTS: CRC-associated alterations were identified in the gut microbiome and serum metabolome. A composite microbe-metabolite diagnostic panel was developed and yielded an area under the curve of 0.912 for adenoma and 0.994 for CRC. We showed that many CRC-associated metabolites were linked to cross-cohort gut microbiome signatures of the disease, including CRC-enriched leucylalanine, serotonin, and imidazole propionate; and CRC-depleted perfluorooctane sulfonate, 2-linoleoylglycerol (18:2), and sphingadienine. CONCLUSIONS: We generated cross-cohort metagenomic signatures of CRC, some of which linked to in-house CRC-associated serum metabolites. The microbial and metabolic shifts may have wide population relevance.


Assuntos
Adenoma , Neoplasias Colorretais , Microbioma Gastrointestinal , Adenoma/diagnóstico , China , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Fezes , Humanos , Metabolômica/métodos , Serotonina
14.
J Med Virol ; 95(1): e28290, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367083

RESUMO

The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015-2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1-/- ) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50 ). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Camundongos , Filogenia , Infecção por Zika virus/epidemiologia , Camboja/epidemiologia , Ásia/epidemiologia
15.
Opt Express ; 31(2): 2345-2358, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785250

RESUMO

Plasmonic nanocavities have emerged as a promising platform for next-generation spectroscopy, sensing and photonic quantum information processing technologies, benefiting from a unique confluence of nanoscale compactness and integrability, ultrafast functionality and room-temperature viability. Harnessing their unprecedented optical field confinement and enhancement properties for such diverse application domains, however, demands continued innovation in cavity design and robust strategies for engineering their plasmonic mode characteristics, with the aim of optimizing spatial and spectral matching conditions for strong light-matter interaction involving embedded quantum emitters. Adopting the canonical gold bowtie nanoantenna, we show that the complex refractive index, n + ik, of the substrate material provides additional design flexibility in tailoring the properties of plasmonic nanocavity modes, including their resonance wavelengths, hotspot locations, intracavity field polarization and radiative decay rates. In particular, we predict that highly refractive (n ≥ 4) or highly absorptive (k ≥ 4) substrates provide two complementary approaches to engineering nanocavity modes that are especially desirable for coupling two-dimensional quantum materials, featuring namely an elevated hotspot with a dominantly in-plane polarized near-field, as well as a strongly radiative character. Our study elucidates the benefits and intricacies of a largely unexplored facet of nanocavity mode manipulation, beyond the widely practiced synthetic control over the cavity topology or physical dimensions, and paves the way for plasmonic cavity quantum electrodynamics with two-dimensional excitonic matter.

16.
Fish Shellfish Immunol ; 134: 108579, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36738947

RESUMO

Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) that can recognize pathogen-associated molecular patterns (PMPs) and play important roles in the innate immune system in vertebrates. In this study, we identified a teleost-specific tlr22 gene from yellow catfish (Pelteobagrus fulvidraco) and its immune roles in response to different pathogens were also determined. The open reading frame (ORF) of the tlr22 was 2892 bp in length, encoding a protein of 963 amino acids. Multiple protein sequences alignment, secondary and three-dimensional structure analyses revealed that TLR22 is highly conserved among different fish species. Phylogenetic analysis showed that the phylogenetic topology was divided into six families of TLR1, TLR3, TLR4, TLR5, TLR7 and TLR11, and TLR22 subfamily was clustered into TLR11 family. Meanwhile, synteny and gene structure comparisons revealed functional and evolutionary conservation of the tlr22 gene in teleosts. Furthermore, tlr22 gene was shown to be widely expressed in detected tissues except barbel and eye, with highest expression level in liver. The transcription of tlr22 was significantly increased in spleen, kidney, liver and gill tissues at different timepoints after Poly I:C infection, suggesting TLR22 plays critical roles in defensing virus invasion. Similarly, the transcription of tlr22 was also dramatically up-regulated in spleen, kidney and gill tissues with different patterns after Aeromonas hydrophila infection, indicating that TLR22 is also involved in resisting bacteria invasion. Our findings will provide a solid basis for the investigation the immune functions of tlr22 gene in teleosts, as well as provide useful information for disease control and treatment for yellow catfish.


Assuntos
Peixes-Gato , Doenças dos Peixes , Animais , Regulação da Expressão Gênica , Aeromonas hydrophila/fisiologia , Filogenia , Receptores Toll-Like/genética , Poli I-C , Proteínas de Peixes/genética
17.
Bioorg Med Chem ; 93: 117457, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688996

RESUMO

KRAS serves as a vital regulator for cellular signaling and drives tumor pathogenesis after mutation. Despite extensive research efforts spanning several decades, targeting KRAS is still challenging due to the multiple KRAS mutations and the emergence of drug resistance. Interfering the interactions between KRAS and SOS1 is one of the promising approaches for modulating KRAS functions. Herein, we discovered small-molecule SOS1 agonists with novel indazole scaffold. Through structure-based optimization, compound 11 was identified with high SOS1 activation potency (p-ERK EC50 = 1.53 µM). In HeLa cells, compound 11 enhances cellular RAS-GTP levels and exhibits biphasic modulation of ERK1/2 phosphorylation through an on-target mechanism and presents the therapeutic potential to modulate RAS signaling by activating SOS1.


Assuntos
Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Células HeLa , Indazóis/farmacologia , Mutação
18.
Phys Chem Chem Phys ; 25(6): 4794-4802, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36692210

RESUMO

We report a joint photoelectron spectroscopic and relativistic quantum chemistry study on gaseous NUO2-. The electron affinity (EA) of the neutral NUO2 molecule is reported for the first time with a value of 2.602(28) eV. The U-O and U-N stretching vibrational modes for the ground state and the first excited state are observed for NUO2. The geometric and electronic structures of both the anions and the corresponding neutrals are investigated by relativistic quantum chemistry calculations to interpret the photoelectron spectra and to provide insights into the nature of the chemical bonding. Both the ground state of the anion and neutral are calculated to be planar structures with C2v symmetry. Unlike the "T"-shape structure of UO3 which has a quasi-linear O-U-O angle, both the ground-state geometries of the anion and neutral have O-U-O bond angles of around 90°. The significant contraction of the O-U-O bond angle indicates the strong interaction between the U and N atoms compared with the "additional" oxygen in UO3. The chemical bonding calculation indicates that multiple bonding of U(VI) can occur in NUO2- and NUO2, and the UVI-N bond is significantly more covalent than the U-O bond. The current experimental and theoretical results reveal the difference between the U-N and U-O bond in the unified molecular system, and expand our understanding of the bonding capacities of actinide elements with the nitrogen atom.

19.
Exp Cell Res ; 419(1): 113303, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35934101

RESUMO

Angiotensin II (Ang II) plays a central role in vascular smooth muscle cell (VSMC) proliferation and migration, being key to regulate vascular function and promote vascular remodeling in cardiovascular diseases. We recently showed that miR-31-5p promoted oxidative stress in spontaneously hypertensive rats. In this study, we aim to investigate whether miR-31-5p and fibronectin type III domain-containing 5 (FNDC5) contribute to Ang II-induced VSMC proliferation and migration. Experiments were performed in primary VSMCs of wide-type (WT) and FNDC5-/- mice as well as the rat A7r5 cell line. We found that Ang II increased miR-31-5p level, reduced FNDC5 expression and stimulated VSMC proliferation and migration, which were aggravated by miR-31-5p mimic, and prevented by miR-31-5p inhibitor in VSMCs. The Ang II-induced VSMC proliferation were prevented by exogenous FNDC5 in both WT and FNDC5-/- mice, while the effects were more significant in FNDC5-/- mice. Furthermore, exogenous FNDC5 reversed the effects of miR-31-5p mimic on VSMC proliferation and migration in Ang II-treated VSMCs. Meanwhile, FNDC5 deficiency prevented the effects of miR-31-5p inhibitor on VSMC proliferation and migration in Ang II-treated VSMCs. In conclusion, our findings demonstrate that the miR-31-5p upregulation and the following FNDC5 downregulation contribute to Ang II-induced VSMC proliferation and migration.


Assuntos
Angiotensina II , MicroRNAs , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Fibronectinas , Camundongos , Músculo Liso Vascular , Miócitos de Músculo Liso , Ratos , Fatores de Transcrição , Regulação para Cima
20.
Proc Natl Acad Sci U S A ; 117(12): 6726-6732, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32156725

RESUMO

The extrahypothalamic growth hormone-releasing hormone (GHRH) and its cognate receptors (GHRH-Rs) and splice variants are expressed in a variety of cancers. It has been shown that the pituitary type of GHRH-R (pGHRH-R) mediates the inhibition of tumor growth induced by GHRH-R antagonists. However, GHRH-R antagonists can also suppress some cancers that do not express pGHRH-R, yet the underlying mechanisms have not been determined. Here, using human esophageal squamous cell carcinoma (ESCC) as a model, we were able to reveal that SV1, a known splice variant of GHRH-R, is responsible for the inhibition induced by GHRH-R antagonist MIA-602. We demonstrated that GHRH-R splice variant 1 (SV1) is a hypoxia-driven promoter of tumor progression. Hypoxia-elevated SV1 activates a key glycolytic enzyme, muscle-type phosphofructokinase (PFKM), through the nuclear factor kappa B (NF-κB) pathway, which enhances glycolytic metabolism and promotes progression of ESCC. The malignant actions induced by the SV1-NF-κB-PFKM pathway could be reversed by MIA-602. Altogether, our studies demonstrate a mechanism by which GHRH-R antagonists target SV1. Our findings suggest that SV1 is a hypoxia-induced oncogenic promoter which can be an alternative target of GHRH-R antagonists.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Receptores LHRH/genética , Sermorelina/análogos & derivados , Processamento Alternativo , Animais , Apoptose , Proliferação de Células , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Glicólise , Humanos , Camundongos , Camundongos Nus , NF-kappa B/genética , NF-kappa B/metabolismo , Fosfofrutoquinase-1 Muscular/genética , Fosfofrutoquinase-1 Muscular/metabolismo , Receptores LHRH/antagonistas & inibidores , Sermorelina/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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