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1.
Nature ; 613(7943): 280-286, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631649

RESUMO

Macroscopic electric motors continue to have a large impact on almost every aspect of modern society. Consequently, the effort towards developing molecular motors1-3 that can be driven by electricity could not be more timely. Here we describe an electric molecular motor based on a [3]catenane4,5, in which two cyclobis(paraquat-p-phenylene)6 (CBPQT4+) rings are powered by electricity in solution to circumrotate unidirectionally around a 50-membered loop. The constitution of the loop ensures that both rings undergo highly (85%) unidirectional movement under the guidance of a flashing energy ratchet7,8, whereas the interactions between the two rings give rise to a two-dimensional potential energy surface (PES) similar to that shown by FOF1 ATP synthase9. The unidirectionality is powered by an oscillating10 voltage11,12 or external modulation of the redox potential13. Initially, we focused our attention on the homologous [2]catenane, only to find that the kinetic asymmetry was insufficient to support unidirectional movement of the sole ring. Accordingly, we incorporated a second CBPQT4+ ring to provide further symmetry breaking by interactions between the two mobile rings. This demonstration of electrically driven continual circumrotatory motion of two rings around a loop in a [3]catenane is free from the production of waste products and represents an important step towards surface-bound14 electric molecular motors.

2.
Mol Cell ; 76(6): 981-997.e7, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31757757

RESUMO

Visualizing the location and dynamics of RNAs in live cells is key to understanding their function. Here, we identify two endonuclease-deficient, single-component programmable RNA-guided and RNA-targeting Cas13 RNases (dCas13s) that allow robust real-time imaging and tracking of RNAs in live cells, even when using single 20- to 27-nt-long guide RNAs. Compared to the aptamer-based MS2-MCP strategy, an optimized dCas13 system is user friendly, does not require genetic manipulation, and achieves comparable RNA-labeling efficiency. We demonstrate that the dCas13 system is capable of labeling NEAT1, SatIII, MUC4, and GCN4 RNAs and allows the study of paraspeckle-associated NEAT1 dynamics. Applying orthogonal dCas13 proteins or combining dCas13 and MS2-MCP allows dual-color imaging of RNAs in single cells. Further combination of dCas13 and dCas9 systems allows simultaneous visualization of genomic DNA and RNA transcripts in living cells.


Assuntos
Imagem Molecular/métodos , RNA/fisiologia , Imagem Individual de Molécula/métodos , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Humanos , Mucina-4 , Engenharia de Proteínas/métodos , RNA Guia de Cinetoplastídeos/genética , RNA Longo não Codificante , Ribonucleases/genética , Ribonucleases/metabolismo , Coloração e Rotulagem/métodos
3.
Mol Cell ; 68(5): 940-954.e3, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29174924

RESUMO

Many eukaryotic genes generate linear mRNAs and circular RNAs, but it is largely unknown how the ratio of linear to circular RNA is controlled or modulated. Using RNAi screening in Drosophila cells, we identify many core spliceosome and transcription termination factors that control the RNA outputs of reporter and endogenous genes. When spliceosome components were depleted or inhibited pharmacologically, the steady-state levels of circular RNAs increased while expression of their associated linear mRNAs concomitantly decreased. Upon inhibiting RNA polymerase II termination via depletion of the cleavage/polyadenylation machinery, circular RNA levels were similarly increased. This is because readthrough transcripts now extend into downstream genes and are subjected to backsplicing. In total, these results demonstrate that inhibition or slowing of canonical pre-mRNA processing events shifts the steady-state output of protein-coding genes toward circular RNAs. This is in part because nascent RNAs become directed into alternative pathways that lead to circular RNA production.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Precursores de RNA/biossíntese , Splicing de RNA , RNA Mensageiro/biossíntese , RNA/biossíntese , Spliceossomos/genética , Transcrição Gênica , Animais , Linhagem Celular , Proteínas de Drosophila/biossíntese , Drosophila melanogaster/metabolismo , Lacase/biossíntese , Lacase/genética , RNA/genética , Interferência de RNA , RNA Polimerase II/metabolismo , Precursores de RNA/genética , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Estabilidade de RNA , RNA Circular , RNA Mensageiro/genética , Ribonucleoproteínas Nucleolares Pequenas/genética , Ribonucleoproteínas Nucleolares Pequenas/metabolismo , Spliceossomos/metabolismo , Terminação da Transcrição Genética , Transfecção
4.
J Am Chem Soc ; 146(14): 9801-9810, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38551407

RESUMO

The sequence-controlled assembly of nucleic acids and amino acids into well-defined superstructures constitutes one of the most revolutionary technologies in modern science. The elaboration of such superstructures from carbohydrates, however, remains elusive and largely unexplored on account of their intrinsic constitutional and configurational complexity, not to mention their inherent conformational flexibility. Here, we report the bottom-up assembly of two classes of hierarchical superstructures that are formed from a highly flexible cyclo-oligosaccharide─namely, cyclofructan-6 (CF-6). The formation of coordinative bonds between the oxygen atoms of CF-6 and alkali metal cations (i) locks a myriad of flexible conformations of CF-6 into a few rigid conformations, (ii) bridges adjacent CF-6 ligands, and (iii) gives rise to the multiple-level assembly of three extended frameworks. The hierarchical superstructures present in these frameworks have been shown to modulate their nanomechanical properties. This research highlights the unique opportunities of constructing convoluted superstructures from carbohydrates and should encourage future endeavors in this underinvestigated field of science.


Assuntos
Carboidratos , Metais , Metais/química , Carboidratos/química , Conformação Molecular , Aminoácidos
5.
J Virol ; 97(3): e0194222, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36856422

RESUMO

African swine fever virus (ASFV) is a large DNA virus that causes African swine fever (ASF), an acute and hemorrhagic disease in pigs with lethality rates of up to 100%. To date, how ASFV efficiently suppress the innate immune response remains enigmatic. In this study, we identified ASFV cysteine protease pS273R as an antagonist of type I interferon (IFN). Overexpression of pS273R inhibited JAK-STAT signaling triggered by type I IFNs. Mechanistically, pS273R interacted with STAT2 and recruited the E3 ubiquitin ligase DCST1, resulting in K48-linked polyubiquitination at K55 of STAT2 and subsequent proteasome-dependent degradation of STAT2. Furthermore, such a function of pS273R in JAK-STAT signaling is not dependent on its protease activity. These findings suggest that ASFV pS273R is important to evade host innate immunity. IMPORTANCE ASF is an acute disease in domestic pigs caused by infection with ASFV. ASF has become a global threat with devastating economic and ecological consequences. To date, there are no commercially available, safe, and efficacious vaccines to prevent ASFV infection. ASFV has evolved a series of strategies to evade host immune responses, facilitating its replication and transmission. Therefore, understanding the immune evasion mechanism of ASFV is helpful for the development of prevention and control measures for ASF. Here, we identified ASFV cysteine protease pS273R as an antagonist of type I IFNs. ASFV pS273R interacted with STAT2 and mediated degradation of STAT2, a transcription factor downstream of type I IFNs that is responsible for induction of various IFN-stimulated genes. pS273R recruited the E3 ubiquitin ligase DCST1 to enhance K48-linked polyubiquitination of STAT2 at K55 in a manner independent of its protease activity. These findings suggest that pS273R is important for ASFV to escape host innate immunity, which sheds new light on the mechanisms of ASFV immune evasion.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Cisteína Proteases , Interferon Tipo I , Animais , Cisteína Proteases/genética , Cisteína Proteases/metabolismo , Imunidade Inata/genética , Interferon Tipo I/metabolismo , Sus scrofa , Suínos , Ubiquitina-Proteína Ligases/metabolismo , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais
6.
PLoS Pathog ; 18(1): e1010270, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35089988

RESUMO

ASFV is a large DNA virus that is highly pathogenic in domestic pigs. How this virus is sensed by the innate immune system as well as why it is so virulent remains enigmatic. In this study, we show that the ASFV genome contains AT-rich regions that are recognized by the DNA-directed RNA polymerase III (Pol-III), leading to viral RNA sensor RIG-I-mediated innate immune responses. We further show that ASFV protein I267L inhibits RNA Pol-III-RIG-I-mediated innate antiviral responses. I267L interacts with the E3 ubiquitin ligase Riplet, disrupts Riplet-RIG-I interaction and impairs Riplet-mediated K63-polyubiquitination and activation of RIG-I. I267L-deficient ASFV induces higher levels of interferon-ß, and displays compromised replication both in primary macrophages and pigs compared with wild-type ASFV. Furthermore, I267L-deficiency attenuates the virulence and pathogenesis of ASFV in pigs. These findings suggest that ASFV I267L is an important virulence factor by impairing innate immune responses mediated by the RNA Pol-III-RIG-I axis.


Assuntos
Vírus da Febre Suína Africana/patogenicidade , Imunidade Inata/imunologia , Fatores de Virulência/imunologia , Virulência/imunologia , Febre Suína Africana/imunologia , Vírus da Febre Suína Africana/imunologia , Animais , RNA Polimerase III/imunologia , Receptores de Superfície Celular/imunologia , Suínos
7.
Mol Cell ; 64(3): 534-548, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27871485

RESUMO

We identify a type of polycistronic transcript-derived long noncoding RNAs (lncRNAs) that are 5' small nucleolar RNA (snoRNA) capped and 3' polyadenylated (SPAs). SPA processing is associated with nascent mRNA 3' processing and kinetic competition between XRN2 trimming and Pol II elongation. Following cleavage/polyadenylation of its upstream gene, the downstream uncapped pre-SPA is trimmed by XRN2 until this exonuclease reaches the co-transcriptionally assembled snoRNP. This snoRNP complex prevents further degradation, generates a snoRNA 5' end, and allows continuous Pol II elongation. The imprinted 15q11-q13 encodes two SPAs that are deleted in Prader-Willi syndrome (PWS) patients. These lncRNAs form a nuclear accumulation that is enriched in RNA binding proteins (RBPs) including TDP43, RBFOX2, and hnRNP M. Generation of a human PWS cellular model by depleting these lncRNAs results in altered patterns of RBPs binding and alternative splicing. Together, these results expand the diversity of lncRNAs and provide additional insights into PWS pathogenesis.


Assuntos
Sequência de Bases , Síndrome de Prader-Willi/genética , RNA Longo não Codificante/genética , RNA Nucleolar Pequeno/genética , Deleção de Sequência , Transcrição Gênica , Processamento Alternativo , Cromossomos Humanos Par 15 , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Exorribonucleases/genética , Exorribonucleases/metabolismo , Loci Gênicos , Impressão Genômica , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/patologia , Humanos , Síndrome de Prader-Willi/metabolismo , Síndrome de Prader-Willi/patologia , Ligação Proteica , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , RNA Longo não Codificante/metabolismo , RNA Nucleolar Pequeno/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
8.
J Vis ; 24(2): 1, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300556

RESUMO

The intricate interrelationships between visual acuity (VA) and stereopsis depend on an array of factors, incorporating the nature of vision impairment, its manifestation (monocular versus binocular), and the classification of stereopsis test symbols used. The objectives of this study were to methodically dissect these multifaceted interactions by simulating a diverse range of vision loss conditions. Thirty medical students with normal vision were subjected to simulated vision loss through opacification and blurring methodologies. Stereopsis was assessed at a distance using both contour-based and random-dot-based symbols under equal binocular and varied monocular VA conditions. In this study, opacification consistently affected stereopsis more than blurring at equivalent VA reductions. However, this difference was absent in contour-based symbols under binocular vision impairment conditions. Significant differences in stereopsis emerged between monocular and binocular vision within the opacification contour-based groups. These differences were less evident in the opacification and blurring groups using random-dot-based patterns. In terms of symbols, the contour-based test demonstrated superior results to the random-dot-based test, particularly under decreased VA. In sum, the method of VA reduction and the choice of stereogram significantly impact distance stereopsis outcomes. This understanding can guide clinical assessments of stereopsis in individuals with varying visual impairments.


Assuntos
Baixa Visão , Humanos , Percepção de Profundidade , Visão Binocular , Acuidade Visual
9.
Int J Mol Sci ; 25(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38928077

RESUMO

Mechanical ventilation (MV), used in patients with acute lung injury (ALI), induces diaphragmatic myofiber atrophy and contractile inactivity, termed ventilator-induced diaphragm dysfunction. Phosphoinositide 3-kinase-γ (PI3K-γ) is crucial in modulating fibrogenesis during the reparative phase of ALI; however, the mechanisms regulating the interactions among MV, myofiber fibrosis, and PI3K-γ remain unclear. We hypothesized that MV with or without bleomycin treatment would increase diaphragm muscle fibrosis through the PI3K-γ pathway. Five days after receiving a single bolus of 0.075 units of bleomycin intratracheally, C57BL/6 mice were exposed to 6 or 10 mL/kg of MV for 8 h after receiving 5 mg/kg of AS605240 intraperitoneally. In wild-type mice, bleomycin exposure followed by MV 10 mL/kg prompted significant increases in disruptions of diaphragmatic myofibrillar organization, transforming growth factor-ß1, oxidative loads, Masson's trichrome staining, extracellular collagen levels, positive staining of α-smooth muscle actin, PI3K-γ expression, and myonuclear apoptosis (p < 0.05). Decreased diaphragm contractility and peroxisome proliferator-activated receptor-γ coactivator-1α levels were also observed (p < 0.05). MV-augmented bleomycin-induced diaphragm fibrosis and myonuclear apoptosis were attenuated in PI3K-γ-deficient mice and through AS605240-induced inhibition of PI3K-γ activity (p < 0.05). MV-augmented diaphragm fibrosis after bleomycin-induced ALI is partially mediated by PI3K-γ. Therapy targeting PI3K-γ may ameliorate MV-associated diaphragm fibrosis.


Assuntos
Lesão Pulmonar Aguda , Bleomicina , Diafragma , Modelos Animais de Doenças , Fibrose , Camundongos Endogâmicos C57BL , Animais , Bleomicina/efeitos adversos , Diafragma/metabolismo , Diafragma/patologia , Camundongos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/metabolismo , Masculino , Respiração Artificial/efeitos adversos , Classe Ib de Fosfatidilinositol 3-Quinase/metabolismo , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Fator de Crescimento Transformador beta1/metabolismo , Apoptose/efeitos dos fármacos , Quinoxalinas , Tiazolidinedionas
10.
J Am Chem Soc ; 145(3): 1855-1865, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36642916

RESUMO

Cocrystal engineering, involving the assembly of two or more components into a highly ordered solid-state superstructure, has emerged as a popular strategy for tuning the photophysical properties of crystalline materials. The reversible co-assembly and disassembly of multicomponent cocrystals and their reciprocal transformation in the solid state remain challenging objectives. Herein, we report a color-tunable upconversion-emission switch based on the interconversion between two cocrystals. One red- and one yellow-emissive cocrystal, composed of an electron-deficient naphthalenediimide-based triangular macrocycle and different electron donors, have been obtained. The red- and yellow-emissive cocrystals undergo reversible transformations on exchanging the electron donors. Benefiting from intermolecular charge transfer interactions, the two cocrystals display superior two-photon excited upconversion emission. Accompanying the interconversion of the two cocrystals, their luminescent color changes between red and yellow, forming a dual-color upconversion-emission switch. This research provides a rare yet critical example involving precise control of cocrystal-to-cocrystal transformation and affords a reference for fabricating color-tunable nonlinear optical materials in the solid state.

11.
J Am Chem Soc ; 145(33): 18402-18413, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37578165

RESUMO

Organic trisradicals featuring threefold symmetry have attracted significant interest because of their unique magnetic properties associated with spin frustration. Herein, we describe the synthesis and characterization of a triangular prism-shaped organic cage for which we have coined the name PrismCage6+ and its trisradical trication─TR3(•+). PrismCage6+ is composed of three 4,4'-bipyridinium dications and two 1,3,5-phenylene units bridged by six methylene groups. In the solid state, PrismCage6+ adopts a highly twisted conformation with close to C3 symmetry as a result of encapsulating one PF6- anion as a guest. PrismCage6+ undergoes stepwise reduction to its mono-, di-, and trisradical cations in MeCN on account of strong electronic communication between its 4,4'-bipyridinium units. TR3(•+), which is obtained by the reduction of PrismCage6+ employing CoCp2, adopts a triangular prism-shaped conformation with close to C2v symmetry in the solid state. Temperature-dependent continuous-wave and nutation-frequency-selective electron paramagnetic resonance spectra of TR3(•+) in frozen N,N-dimethylformamide indicate its doublet ground state. The doublet-quartet energy gap of TR3(•+) is estimated to be -0.08 kcal mol-1, and the critical temperature of spin-state conversion is found to be ca. 50 K, suggesting that it displays pronounced spin frustration at the molecular level. To the best of our knowledge, this example is the first organic radical cage to exhibit spin frustration. The trisradical trication of PrismCage6+ opens up new possibilities for fundamental investigations and potential applications in the fields of both organic cages and spin chemistry.

12.
Small ; 19(40): e2301934, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37271893

RESUMO

Supramolecular hydrogels involved macrocycles have been explored widely in recent years, but it remains challenging to develop hydrogel based on solitary macrocycle with super gelation capability. Here, the construction of lantern[33 ]arene-based hydrogel with low critical gelation concentration (0.05 wt%), which can be used for efficient oil-water separation, is reported. The lantern[33 ]arenes self-assemble into hydrogen-bonded organic nanoribbons, which intertwine into entangled fibers to form hydrogel. This hydrogel which exhibits reversible pH-responsiveness characteristics can be coated on stainless-steel mesh by in situ sol-gel transformation. The resultant mesh exhibits excellent oil-water separation efficiency (>99%) and flux (>6 × 104 L m-2 h-1 ). This lantern[33 ]arene-based hydrogel not only sheds additional light on the gelation mechanisms for supramolecular hydrogels, but also extends the application of macrocycle-based hydrogels as functional interfacial materials.

13.
RNA Biol ; 20(1): 419-430, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37405372

RESUMO

The genetic disorder Prader-Willi syndrome (PWS) is mainly caused by the loss of multiple paternally expressed genes in chromosome 15q11-q13 (the PWS region). Early diagnosis of PWS is essential for timely treatment, leading to effectively easing some clinical symptoms. Molecular approaches for PWS diagnosis at the DNA level are available, but the diagnosis of PWS at the RNA level has been limited. Here, we show that a cluster of paternally transcribed snoRNA-ended long noncoding RNAs (sno-lncRNAs, sno-lncRNA1-5) derived from the SNORD116 locus in the PWS region can serve as diagnostic markers. In particular, quantification analysis has revealed that 6,000 copies of sno-lncRNA3 are present in 1 µL whole blood samples from non-PWS individuals. sno-lncRNA3 is absent in all examined whole blood samples of 8 PWS individuals compared to 42 non-PWS individuals and dried blood samples of 35 PWS individuals compared to 24 non-PWS individuals. Further developing a new CRISPR-MhdCas13c system for RNA detection with a sensitivity of 10 molecules per µL has ensured sno-lncRNA3 detection in non-PWS, but not PWS individuals. Together, we suggest that the absence of sno-lncRNA3 represents a potential marker for PWS diagnosis that can be detected by both RT-qPCR and CRISPR-MhdCas13c systems with only microlitre amount of blood samples. Such an RNA-based sensitive and convenient approach may facilitate the early detection of PWS.


Assuntos
Síndrome de Prader-Willi , RNA Longo não Codificante , Humanos , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética , RNA Longo não Codificante/genética , RNA Nucleolar Pequeno/genética
14.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36982609

RESUMO

Mechanical ventilation (MV) used in patients with acute lung injury (ALI) induces lung inflammation and causes fibroblast proliferation and excessive collagen deposition-a process termed epithelial-mesenchymal transition (EMT). Phosphoinositide 3-kinase-γ (PI3K-γ) is crucial in modulating EMT during the reparative phase of ALI; however, the mechanisms regulating the interactions among MV, EMT, and PI3K-γ remain unclear. We hypothesized that MV with or without bleomycin treatment would increase EMT through the PI3K-γ pathway. C57BL/6 mice, either wild-type or PI3K-γ-deficient, were exposed to 6 or 30 mL/kg MV for 5 h after receiving 5 mg/kg AS605240 intraperitoneally 5 days after bleomycin administration. We found that, after bleomycin exposure in wild-type mice, high-tidal-volume MV induced substantial increases in inflammatory cytokine production, oxidative loads, Masson's trichrome staining level, positive staining of α-smooth muscle actin, PI3K-γ expression, and bronchial epithelial apoptosis (p < 0.05). Decreased respiratory function, antioxidants, and staining of the epithelial marker Zonula occludens-1 were also observed (p < 0.05). MV-augmented bleomycin-induced pulmonary fibrogenesis and epithelial apoptosis were attenuated in PI3K-γ-deficient mice, and we found pharmacological inhibition of PI3K-γ activity through AS605240 (p < 0.05). Our data suggest that MV augmented EMT after bleomycin-induced ALI, partially through the PI3K-γ pathway. Therapy targeting PI3K-γ may ameliorate MV-associated EMT.


Assuntos
Lesão Pulmonar Aguda , Fosfatidilinositol 3-Quinases , Camundongos , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Bleomicina/toxicidade , Camundongos Endogâmicos C57BL , Pulmão/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo
15.
Curr Issues Mol Biol ; 44(4): 1701-1712, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35723375

RESUMO

Sepsis may induce immunosuppression and result in death. S100A12 can bind to the receptor for advanced glycation end-products (RAGE) and Toll-like receptor (TLR)4 following induction of various inflammatory responses. It is unclear whether S100A12 significantly influences the immune system, which may be associated with sepsis-related mortality. We measured plasma S100A12 levels and cytokine responses (mean ± standard error mean) of lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) after S100A12 inhibition in healthy controls and patients with sepsis on days one and seven. Day one plasma soluble RAGE (sRAGE) and S100A12 levels in patients with sepsis were significantly higher than those in controls (2481.3 ± 295.0 vs. 1273.0 ± 108.2 pg/mL, p < 0.001; 530.3 ± 18.2 vs. 310.1 ± 28.1 pg/mL, p < 0.001, respectively). Day seven plasma S100A12 levels in non-survivors were significantly higher than those in survivors (593.1 ± 12.7 vs. 499.3 ± 23.8 pg/mL, p = 0.002, respectively). In survivors, plasma sRAGE levels were significantly decreased after 6 days (2297.3 ± 320.3 vs. 1530.1 ± 219.1 pg/mL, p = 0.009, respectively), but not in non-survivors. Inhibiting S100A12 increased the production of tumor necrosis factor (TNF)-α and interleukin (IL)-10 in stimulated PBMCs for both controls and patients. Therefore, S100A12 plays an important role in sepsis pathogenesis. S100A12 may competitively bind to TLR4 and RAGE, resulting in decreased IL-10 and TNF-α production.

16.
Crit Care Med ; 50(11): 1577-1587, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35916411

RESUMO

OBJECTIVES: Hyperphenylalaninemia predicts poor outcomes in patients with cardiovascular disease. However, the prognostic value and factors associated with stress hyperphenylalaninemia (SHP) were unknown in critical patients in the cardiac ICU. DESIGN: Prospective observational study. SETTING: Single-center, cardiac ICU in Taiwan. PATIENTS: Patients over 20 years old with Acute Physiology And Chronic Health Evaluation II scores greater than or equal to 15 and/or ventilatory support in the cardiac ICU. INTERVENTIONS: We measured plasma phenylalanine levels serially during patients' stays in the ICU to investigate their prognostic value for 90-day mortality. Gene array was performed to identify genetic polymorphisms associated with SHP (phenylalanine level ≥ 11.2 µmol/dL) and to develop a Genetic Risk Score (GRS). We analyzed the associations between SHP and clinical factors and genetic variants and identified the correlation between pteridines and genetic variants. MEASUREMENTS AND MAIN RESULTS: The study enrolled 497 patients. Increased phenylalanine concentration was independently associated with increased mortality risk. Patients with SHP had a higher mortality risk compared with those without SHP (log rank = 41.13; p < 0.001). SHP was associated with hepatic and renal dysfunction and with genetic polymorphisms on the pathway of tetrahydrobiopterin (BH4) synthesis (CBR1 and AKR1C3) and recycling (PCBD2). Higher GRSs were associated with lower BH4 bioavailability in response to stress ( p < 0.05). In patients without SHP at baseline, those with GRSs gretaer than or equal to 2 had a higher frequency of developing SHP during the ICU stay (31.5% vs 16.1%; p = 0.001) and a higher mortality risk ( p = 0.004) compared with those with GRSs less than 2. In patients with SHP at baseline, genetic variants did not provide additional prognostic value. CONCLUSIONS: SHP in patients admitted to the ICU was associated with a worse prognosis. In patients without SHP, genetic polymorphisms associated with SHP measured using a GRS of greater than or equal to 2 was associated with the subsequent SHP and higher mortality risk.


Assuntos
Unidades de Terapia Intensiva , Pteridinas , APACHE , Adulto , Humanos , Fenilalanina/genética , Prognóstico , Estudos Prospectivos , Adulto Jovem
17.
Acc Chem Res ; 54(8): 2027-2039, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33793191

RESUMO

ConspectusMacrocycles have had a profound influence on the establishment of supramolecular chemistry because of their abundant molecular recognition and self-assembly characteristics. The design of new macrocyclic receptors that can be tailored by synthesis to display new and exotic properties is an important research objective for chemists and materials scientists. Rigid macrocycles with π-conjugated aromatic units, in contrast with flexible ones, tend to possess large interior and exterior π-surfaces in addition to persistent shapes. These features not only endow these macrocycles with a wide range of host-guest properties but also render them ideal building blocks for constructing a diverse variety of supramolecular architectures. The incorporation of π-conjugated units into macrocycles also imbues them with a wealth of optical, electronic, and magnetic properties, resulting in their broad application in materials science and molecular nanotechnology.Recently, we have designed and synthesized a new class of macrocycles, namely, molecular triangles, which have rigid structures with triangular geometries. They consist of three chiral trans-1,2-cyclohexano apexes and three aromatic tetracarboxylic diimide linkers, such as pyromellitic diimide, naphthalene diimide, and perylene diimide. Benefiting from the availability of facile synthetic protocols, the geometries and properties of these rigid molecular triangles can be altered at will. By combining these tetracarboxylic diimide linkers, we have been able to synthesize both molecular equilateral and isosceles triangles. During the past few years, we have conducted research in a systematic manner on the structural features and self-assembly characteristics of these molecular triangles. The following points are worthy of note regarding these molecular triangles: (i) They possess shape-persistent inner cavities of a highly electron-deficient nature. These features endow them with the ability to complex with anions and electron-rich molecules, forming supramolecular nanotubes and two-dimensional tilings. (ii) Those with intrinsic chirality are able to self-assemble into solid-state nonhelical or single-handed helical superstructures, inducing selective chirality transfer from the macrocycles to their crystalline supramolecular assemblies. (iii) The triangular arrangement of aromatic tetracarboxylic diimide linkers contributes to through-space electron delocalization encompassing the entire macrocycle, conferring exotic electronic and spin properties. To date, the family of molecular triangles has exhibited a range of physicochemical properties, such as anion recognition, chiral assembly, supramolecular gelation, energy storage, solid-state luminescence, and nonlinear optical response.In this Account, we summarize our recent progress in research into these molecular triangles. We present an overview of their design and synthesis, as well as a general summary of their structural features. Thereafter, we discuss state-of-the-art developments in relation to their molecular recognition properties and their assembly characteristics. In addition, we highlight the potential applications of these molecular triangles and their complexes with a range of solvents and electron-rich molecules. Finally, we speculate on further structural modifications and application-oriented explorations based on this class of molecular triangles.

18.
Arterioscler Thromb Vasc Biol ; 41(12): 2877-2889, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34645279

RESUMO

OBJECTIVE: METTL3 (methyltransferase-like protein 3)-mediated N6-methyladenosine modification is the most abundant RNA modification on eukaryote mRNAs and plays a crucial role in diverse physiological and pathological processes. However, whether N6-methyladenosine modification has function in thrombosis is unknown. This study aims to determine the role of METTL3 in the endothelial cells-mediated thrombosis. Approach and Results: RNA-sequencing and real-time quantitative PCR revealed that the expression of PAI-1 (plasminogen activator inhibitor-1) was downregulated in METTL3 knockdown human umbilical vein endothelial cells. In vitro experiments showed that METTL3 suppressed fibrinolysis. Mechanically, RNA methylation sequencing and meRIP-quantitative real-time PCR showed that METTL3 catalyzed N6-methyladenosine modification on 3' UTR of JUN mRNA. Western blotting analysis showed that METTL3 promoted JUN protein expression. Chromatin immunoprecipitation analysis demonstrated that JUN bound to the PAI-1 promoter in human umbilical vein endothelial cells. Furthermore, mice challenged with lipopolysaccharide resulted in higher METTL3 expression in vessels. Endothelial-specific knockdown of Mettl3 decreased expression of active PAI-1 in plasma and attenuated fibrin deposition in livers and lungs during endotoxemia. CONCLUSIONS: Our study reveals that METTL3-mediated N6-methyladenosine modification plays a crucial role in fibrinolysis and is an underlying target for the therapy of thrombotic disorders.


Assuntos
Endotélio Vascular/metabolismo , Fibrinólise , Metiltransferases/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Proteínas de Ligação a RNA/metabolismo , Trombose/metabolismo , Regiões 3' não Traduzidas , Animais , Regulação para Baixo , Genes jun , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Regulação para Cima
19.
Sleep Breath ; 26(2): 549-558, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34145538

RESUMO

PURPOSE: Continuous positive airway pressure (CPAP) is a standard treatment for obstructive sleep apnea (OSA). However, CPAP has limitations. High-flow nasal cannula (HFNC) is already in use for various types of respiratory diseases. As HFNC generates positive airway pressure, it may be a potential candidate for OSA treatment. This prospective study compared the therapeutic effects of HFNC to CPAP in patients with OSA. METHODS: Patients whose apnea-hypopnea index (AHI) was > 5 events/h were enrolled in this study. All participants were randomly divided into two groups. The first group underwent CPAP the first night and HFNC the second night. Conversely, the second group received HFNC the first night and CPAP the second night. Their respiratory events and sleep quality were compared using baseline polysomnography, CPAP, and HFNC. RESULTS: In total, 28 participants completed this study. Median [interquartile range] AHI (35.0 [20.0-48.6] vs. 10.8 [5.5-20.6] events/h; p < 0.001) was significantly improved by the HFNC. However, sleep quality was not improved. When CPAP was compared directly with HFNC, CPAP demonstrated a more favorable effect for respiratory events (AHI 5.0 [2.0-7.0] vs. 10.8 [5.5-20.6] events/h; p < 0.001) and sleep efficiency (88.1 [79.9-92.5] vs. 77.9 [69.2-86.6] %; p = 0.001). CONCLUSION: The efficacy of CPAP was superior to HFNC for both respiratory events and sleep quality. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03843372; URL: www. CLINICALTRIALS: gov ; Date of registration: November 2, 2019.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Apneia Obstrutiva do Sono , Cânula , Humanos , Polissonografia , Estudos Prospectivos , Apneia Obstrutiva do Sono/terapia
20.
Altern Ther Health Med ; 28(1): 72-79, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34559685

RESUMO

BACKGROUND: Tuberculosis (TB) infection triggers the innate and adaptive immune responses. Eucommia ulmoides Oliv., Gynostemma pentaphyllum (Thunb.) Makino, and Curcuma longa L. extracts exhibit various immunomodulatory effects. OBJECTIVE: This study aimed to determine the effects of 3 extracts used in Traditional Chinese Medicine (TCM) on cytokine production in peripheral blood mononuclear cells (PBMCs) obtained from patients with TB. DESIGN: The research team performed an in vitro study with self controls. SETTING: The study took place at the Department of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Taiwan. PARTICIPANTS: 18 patients diagnosed with pulmonary TB were enrolled in the study. INTERVENTION: Purified protein derivative (PPD)-stimulated PBMCs were cultured for 48 h in the presence and absence of 0.05 or 0.1 mg/mL of herbal extracts. OUTCOME MEASURES: Cytokine levels of interferon (IFN)-γ, interleukin (IL)-10, IL-12, tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-ß1 in the culture supernatant were measured. RESULTS: C longa L., E ulmoides Oliv. and G pentaphyllum (Thunb.) Makino extracts decreased IFN-γ production in PPD-stimulated PBMCs. C longa L. extract did not exhibit a marked and consistent effect on the production of IL-10, IL-12, TNF-α and TGF-ß1. E ulmoides Oliv. extract increased the production of IL-10, TNF-α and TGF-ß1. G pentaphyllum (Thunb.) Makino extract increased the production of IL-10, IL-12, TNF-α and TGF-ß1. CONCLUSION: These results show that G pentaphyllum (Thunb.) Makino might enhance cell immunity since it increased the production of IL-12 and TNF-α with dose effect.


Assuntos
Eucommiaceae , Tuberculose , Curcuma , Citocinas , Gynostemma , Humanos , Leucócitos Mononucleares , Extratos Vegetais/farmacologia
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