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1.
Angew Chem Int Ed Engl ; 62(23): e202302266, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37009840

RESUMO

Chiral shape-persistent molecular nanocarbons are promising chiroptical materials; their synthesis, however, remains a big challenge. Herein, we report the facile synthesis and chiral resolution of a double-stranded figure-eight carbon nanobelt 1 in which two [5]helicene units are fused together. Two synthetic routes were developed, and, in particular, a strategy involving Suzuki coupling-mediated macrocyclization followed by Bi(OTf)3 -catalyzed cyclization of vinyl ether turned out to be the most efficient. The structure of 1 was confirmed by X-ray crystallographic analysis. The isolated (P,P)- and (M,M)- enantiomers show persistent chiroptical properties with relatively large dissymmetric factors (|gabs |=5.4×10-3 and |glum |=1.0×10-2 ), which can be explained by the effective electron delocalization along the fully conjugated belt and the unique D2 symmetry. 1 exhibits local aromatic character with a dominant structure containing eight Clar's aromatic sextet rings.

2.
Chemistry ; 29(18): e202203702, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36656133

RESUMO

Construction of sub-5 nm long-range ordered structures through self-assembly has received increasing attention. Herein, a series of ODMS-based thermotropic liquid crystals (LCs) containing perylene diimide (PDI) were designed and synthesized. These LCs can form ordered nanostructures with periodic sizes around 5 nm including smectic J (SmJ), oblique columnar (Colob ), and hexagonal columnar (Colh ) phases with change in the volume fraction of ODMS, where the layer spacing of the SmJ phase is less than 5 nm. Thin films with parallel oriented nanolines with line width less than 5 nm can be obtained on PDMS-modified silicon substrates by spin-casting and simple thermal annealing processes. Moreover, owing to the strong π-π interaction between PDI cores, these nanolines are long-range ordered with uniaxial orientation in relatively large areas (1.5×1.5 µm2 ) with over 300 continuous microdomains without pre-patterning. These nanostructures provide the possibility of preparing nanotemplates by oxygen plasma etching.

4.
Anal Methods ; 14(46): 4872-4878, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36416138

RESUMO

An aptamer sensor based on manganese dioxide (MnO2) nanosheets was developed for the detection of zearalenone (ZEN). The ZEN aptamer was modified at the 5'-end by a 6-carboxyfluorescein (6-FAM) fluorophore with self-assembly on MnO2 nanosheets. Interaction of the 6-FAM fluorophore at the 5'-end of the ZEN aptamer with the MnO2 nanosheet lowered fluorescence (FL) intensity due to fluorescence resonance energy transfer (FRET). The introduction of ZEN into the sensing system resulted in hybridization with the ZEN aptamer, forming a stable G-quadruplex/ZEN, which exhibited a low affinity for the MnO2 nanosheet surface. The distance between the 6-FAM fluorophore and MnO2 nanosheet hampered FRET, with a consequent strong FL signal. Under the optimal experimental conditions, the FL intensity of the sensing system showed a good linear correlation with ZEN concentration in the range of 1.5-10.0 ng mL-1, and a detection limit (S/N = 3) of 0.68 ng mL-1. The sensing system delivered enhanced specificity for the detection of ZEN, and can find wide application in the detection of other toxins by replacing the sequence of the recognition aptamer.


Assuntos
Nomes , Zearalenona , Compostos de Manganês , Óxidos , Oligonucleotídeos , Corantes Fluorescentes , Ionóforos
5.
Angew Chem Int Ed Engl ; 61(43): e202210697, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36008354

RESUMO

An [8]cyclo-para-phenylmethine derivative ([8]CPPM-Mes) was synthesized. X-ray analysis revealed a tub-shaped geometry similar to the cyclooctatetraene, with alternating benzenoid/quinoid structure. Variable-temperature NMR measurements disclosed a slow valence tautomerization process with an interconversion energy barrier of about 11.7 kcal mol-1 at coalescence temperature (273 K), and two more lower-barrier dynamic processes involving flipping of the 1,4-phenyl rings on the backbone and rotation of the mesityl substituents. Its dication ([8]CPPM-Mes2+ ) adopts a bowl-like geometry with a smaller depth of the cavity, and a slow bowl inversion process was observed by dynamic NMR. The bond lengths of the benzenoid/quinoid rings are more averaged via electron delocalization and the molecule shows global aromaticity, which was further validated by NMR and theoretical analysis. [8]CPPM-Mes2+ exhibits open-shell diradical character with a small singlet-triplet energy gap (-1.8 kcal mol-1 ).

6.
Chem Commun (Camb) ; 58(1): 108-111, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34875677

RESUMO

A series of tetraphenylporphyrin-based thermotropic liquid crystals containing oligo(dimethylsiloxane) were synthesized. These disc-coil hybrids form ordered nanostructures with periodic sizes on the sub-5 nm scale, including oblique columnar, lamellar, and hexagonal columnar phases. Films with sub-5 nm line patterns and homeotropically aligned columnar structures can be obtained by substrate-induced self-assembly.

7.
J Am Chem Soc ; 143(39): 15924-15929, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550688

RESUMO

Twisted carbon nanobelts could display persistent chirality, which is desirable for material applications, but their synthesis is very challenging. Herein, we report the successful synthesis and chiral resolution of such a kind of molecules (1-H and 1) with a figure-eight configuration. 1-H was synthesized first by macrocyclization through Suzuki coupling reaction followed by benzannulation via Bi(OTf)3-mediated cyclization reaction of vinyl ether. Oxidative dehydrogenation of 1-H gave the fully π-conjugated 1. Their twisted structures were confirmed by X-ray crystallographic analysis and calculations, and they can be resolved by chiral high-performance liquid chromatography. The isolated enantiomers showed persistent chiroptical properties according to the circular dichroism measurements, with moderate |gabs| values (0.0016 for 1-H and 0.005-0.007 for 1). Their photophysical properties were also briefly studied.

8.
Pharmazie ; 76(4): 159-164, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33849701

RESUMO

Objective: To investigate the immune cellular and genomic profiles of bisphosphonates-related osteonecrosis (BRONJ) of the jaw and excavate potential small molecule drugs. Methods and materials: The genomic profile of a multiple myeloma (MM) patient with BRONJ was downloaded from Gene Expression Omnibus (GEO). The 22 immune cell subsets infiltration in the patient were predicted by cell-type identification by estimating relative subsets of RNA transcripts. In addition, the differently expressed immune-related genes (DEMGs) of BRONJ were identified, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses for functional annotation. Then, potential drugs for BRONJ treatment were predicted by Connectivity Map (CMAP) based on DEGs. Results: High proportions of native CD4+T cells and M0 macrophages were observed while resting mast cells, NK cells, and eosinophils were downregulated in the BRONJ patient (P< 0.05). Resting dendritic cells and gamma delta T cells were positively correlated (r=0.93). Additionally, 36 DEMGs were screened from 336 DEGs in BRONJ expression profiles. GO enrichment analysis revealed that DEMGs were most associated with peptidyl-tyrosine modification, myeloid leukocyte migration, leukocyte chemotaxis and regulation of chemokine production(P<0.05). KEGG analysis indicated that DEMGs were mainly related to cytokine-cytokine receptor interaction, IL-17 signaling pathway and NF-Kappa B signaling pathway(P<0.05). Besides, 12 small molecule drugs were screened in MM patient with ONJ. Conclusion: The discovery of different composition of immune cell types and immune-related transcriptomes in BRONJ helps to explain the onset and development of MRONJ, which provides a novel target for BRONJ therapy.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/genética , Difosfonatos/efeitos adversos , Mieloma Múltiplo/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/imunologia , Células Dendríticas/imunologia , Difosfonatos/administração & dosagem , Eosinófilos/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genômica/métodos , Humanos , Células Matadoras Naturais/imunologia , Mastócitos/imunologia
9.
J Biomater Sci Polym Ed ; 31(4): 456-471, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801405

RESUMO

Synergistic delivery of two drugs is a desirable choice to overcome drug resistance. Resveratrol (RES) and xanthohumol (XAN) which are both new drugs originated from plants exhibit great potential in the treatment of cancer, but there are few studies on combining them in a delivery system. In this work, a new core/shell fiber mesh containing RES and XAN was designed out via coaxial electrospinning, and the effect of drug content on the medicated fibers was discovered. RES/polyethylene oxide (PEO) could be well combined with XAN/Poly(lactide-glycolide) (PLGA) to make core/shell fibers, but fibrous morphology worsened with increasing drug content of the core or shell to some extent. The core/shell was amorphous nature, and changing drug content had little influence on the wetability of the core/shell fibers. The release accelerated with drug content increasing in the fibers, and RES and XAN showed gradient release, which the release rate of RES was slower than XAN. These two drugs could sustain release for 350 h. When the blend ratios of RES/PEO and XAN/PLGA were 50/50 and 10/90 in the fibers, the fiber mesh showed the best mechanical properties, of which the tensile strength and elongation at break were 2.85 ± 0.10 MPa and 55.23 ± 2.53%, respectively. The medicated fibers presented good characteristics of inhibiting breast cancer cell activity.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Eletricidade , Flavonoides/administração & dosagem , Propiofenonas/administração & dosagem , Resveratrol/administração & dosagem , Linhagem Celular Tumoral , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos/instrumentação , Humanos , Teste de Materiais , Polietilenoglicóis/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Resistência à Tração , Molhabilidade
10.
ACS Nano ; 13(11): 13474-13485, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31651143

RESUMO

During the past decade, self-assembly of saccharide-containing amphiphilic molecules toward bioinspired functional glycomaterials has attracted continuous attention due to their various applications in fundamental and practical areas. However, it still remains a great challenge to prepare hierarchical glycoassemblies with controllable and diversiform structures because of the complexity of saccharide structures and carbohydrate-carbohydrate interactions. Herein, through hierarchical self-assembly of modulated amphiphilic supramolecular metallocarbohydrates, we successfully prepared various well-defined glyco-nanostructures in aqueous solution, including vesicles, solid spheres, and opened vesicles depending on the molecular structures of metallocarbohydrates. More attractively, these glyco-nanostructures can further transform into other morphological structures in aqueous solutions such as worm-like micelles, tubules, and even tupanvirus-like vesicles (TVVs). It is worth mentioning that distinctive anisotropic structures including the opened vesicles (OVs) and TVVs were rarely reported in glycobased nano-objects. This intriguing diversity was mainly controlled by the subtle structural trade-off of the two major components of the amphiphiles, i.e., the saccharides and metallacycles. To further understand this precise structural control, molecular simulations provided deep physical insights on the morphology evolution and balancing of the contributions from saccharides and metallacycles. Moreover, the multivalency of glyco-nanostructures with different shapes and sizes was demonstrated by agglutination with a diversity of sugar-binding protein receptors such as the plant lectins Concanavalin A (ConA). This modular synthesis strategy provides access to systematic tuning of molecular structure and self-assembled architecture, which undoubtedly will broaden our horizons on the controllable fabrication of biomimetic glycomaterials such as biological membranes and supramolecular lectin inhibitors.


Assuntos
Nanoestruturas/química , Compostos Organometálicos/química , Polissacarídeos/química , Tensoativos/química , Concanavalina A/antagonistas & inibidores , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Simulação de Dinâmica Molecular , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Tamanho da Partícula , Polissacarídeos/farmacologia , Propriedades de Superfície , Tensoativos/síntese química , Tensoativos/farmacologia
12.
J Mol Cell Cardiol ; 131: 12-19, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30998980

RESUMO

The leading cause of genetic dilated cardiomyopathy (DCM) is due to mutations in the TTN gene, impacting approximately 15-20% of familial and 18% of sporadic DCM cases. Currently, there is potential for a personalized RNA-based therapeutic approach in titin-based DCM, utilizing antisense oligonucleotide (AON) mediated exon-skipping, which attempts to reframe mutated titin transcripts, resulting in shortened, functional protein. However, the TTN gene is massive with 363 exons; each newly identified TTN exon mutation provides a challenge to address when considering the potential application of AON mediated exon skipping. In the initial phase of this strategy, the mutated TTN exon requires specific AON design and evaluation to assess the exon skipping effectiveness for subsequent experiments. Here, we present a detailed protocol to effectively assemble and evaluate AONs for efficient exon-skipping in targeted TTN exons. We chose a previously identified TTN 1-bp deletion mutation in exon 335 as an exemplary target exon, which causes a frameshift mutation leading to truncated A-band titin in DCM. We designed two specific AONs to mask the Ttn exon 335 and confirmed successfully mediated exon skipping without disrupting the Ttn reading frame. In addition, we evaluated and confirmed AON-treated HL-1 cells show maintained store-operated calcium entry, fractional shortening as well as preserved sarcomeric formation in comparison to control samples, indicating the treated cardiomyocytes retain adequate, essential cell function and structure, proving the treated cells can compensate for the loss of exon 335. These results indicate our method offers the first systematic protocol in designing and evaluating AONs specifically for mutated TTN target exons, expanding the framework of future advancements in the therapeutic potential of antisense-mediated exon skipping in titin-based DCM.


Assuntos
Cardiomiopatia Dilatada/genética , Conectina/genética , Éxons/genética , Mutação da Fase de Leitura/genética , Oligonucleotídeos Antissenso/genética , Deleção de Sequência/genética , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Sarcômeros/genética
13.
Micromachines (Basel) ; 10(3)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813578

RESUMO

Modern design-conscious products have raised the development of advanced electronic fabricating technologies. These widely used industrial technologies show high compatibility for inorganic materials and capacity for mass production. However, the morphology accuracy is hard to ensure and cracks happen easily, which could cause the degradation of device performance and life span. In order to make high precision 3D conformable electronics, a thermal phase-changing adhesion interlayer and modified fabricating processes are used in self-developed equipment. The working principles and influencing factors such as heating time and geometry parameters are studied quantitatively. The accuracy of fabricated patterns is enhanced by this new technology and serpentine designed structures. The delamination or detachment are significantly alleviated. Due to the operation convenience and compatibility with existing materials, the presented fabrication method has great potential for mass production of 3D curved conformable electronics.

14.
Macromol Rapid Commun ; 39(22): e1800454, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30142240

RESUMO

Chirality-tunable supramolecular metallacycles containing two light-responsive dithienylethene units and two chiral 1,1'-bi-2-naphthol (BINOL) units have been successfully constructed via coordination-driven self-assembly. These new metallacycles are well-characterized with 1D multinuclear NMR (1 H and 31 P NMR), 2D 1 H-1 H COSY and DOSY, ESI-TOF-MS, and PM6 semiempirical molecular orbital methods. Interestingly, upon irradiation with ultraviolet and visible light, the conformation of these metallacycles can undergo reversible transformation between ring-open and ring-closed forms accompanied with the obvious change of CD signals. Further investigation reveals that the photoisomerization of the dithienylethene moieties induces the change in the dihedral angle of the binaphthyl rings, thus leading to the chiral modulation of supramolecular metallacycles. Thus, this study provides very few examples of the light-induced chirality-tunable metallosupramolecular assemblies, which may find potential application in mimicking the function of natural systems in the future.


Assuntos
Naftóis/química , Compostos Organometálicos/química , Substâncias Macromoleculares/química , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos
15.
Circ Arrhythm Electrophysiol ; 11(6): e006242, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29848477

RESUMO

BACKGROUND: Atrial fibrosis is a hallmark of arrhythmogenic structural remodeling in patients with persistent atrial fibrillation (AF) and is negatively correlated with procedure outcome in patients undergoing ablation. However, noninvasive methods to determine the extent of atrial fibrosis are limited. Here, we used microRNA (miRNA) expression analysis to detect markers of left atrial low-voltage areas (LVAs) in patients with persistent AF undergoing catheter ablation. METHODS: We performed 3-dimensional voltage mapping in 102 patients (average age 62.1±13.1 years, CHA2DS2-VASc score of 2.3±1.6, LA size 41.5±5.7 mm) undergoing ablation for persistent AF and determined the extent of left atrial low-voltage. LVAs were defined if bipolar electrogram amplitudes were <0.5 mV during sinus rhythm. Before ablation, we obtained a blood sample, isolated miRNAs, and profiled them on a miRCURY LNA Universal RT microRNA PCR Human panel. RESULTS: Sixty-nine miRNAs were identified in all samples, with an average of 123 miRNAs detectable per sample. We found that the serum concentration of miR-21, a miRNA that has been previously linked to cardiac fibrosis development, was strongly associated with the extent of LVAs determined by voltage mapping. We could confirm that LVAs were negatively correlated with ablation success in a 1-year follow-up. In addition, miR-21 serum levels were associated with AF-free survival after catheter ablation. CONCLUSIONS: Circulating miR-21 correlates with left atrial LVAs and is associated with procedure outcome in patients with persistent AF undergoing ablation.


Assuntos
Função do Átrio Esquerdo , Ablação por Cateter , MicroRNA Circulante/sangue , MicroRNAs/sangue , Potenciais de Ação , Idoso , Fibrilação Atrial/sangue , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , MicroRNA Circulante/genética , Técnicas Eletrofisiológicas Cardíacas , Feminino , Perfilação da Expressão Gênica , Marcadores Genéticos , Frequência Cardíaca , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Recidiva , Fatores de Tempo
16.
Per Med ; 15(2): 127-136, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29714129

RESUMO

Inflammatory cardiomyopathy is the result of persistent myocardial inflammation which can arise from both infectious or noninfectious causes. While most patients with acute myocarditis recover, up to 20% develop inflammatory cardiomyopathy with chronic heart failure. The interaction between host factors and factors of the agent that triggered myocardial inflammation must be considered to fully understand the individual mechanism of disease. Several inflammatory biomarkers, histology, immunohistochemistry, advanced imaging technologies as well as molecular high-throughput sequencing techniques help to identify disease pathways and to establish a comprehensive, individualized treatment approach, which can include anti-inflammatory medication, antiviral drugs and heart failure therapy. This might help to prevent transition from acute inflammation to persistent heart failure and to restore cardiac function.


Assuntos
Cardiomiopatias/genética , Cardiomiopatias/imunologia , Biomarcadores , Cardiomiopatias/complicações , Cardiomiopatia Dilatada/complicações , Insuficiência Cardíaca/complicações , Humanos , Inflamação/complicações , Miocardite/tratamento farmacológico , Miocárdio/metabolismo , Miocárdio/patologia , Medicina de Precisão/efeitos adversos
17.
Chem Commun (Camb) ; 54(18): 2224-2227, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29323676

RESUMO

We present the successful construction of a new family of organometallic rotaxane-terminated dendrimers using neutral platinum-acetylides as the main scaffold. The fourth generation dendrimer has 24 rotaxane moieties on the surface termini in a monodisperse manner.

18.
Inorg Chem ; 57(7): 3516-3520, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29251490

RESUMO

A new discrete supramolecular metallacage functionalized with an alkynylplatinum(ll) 2,6-bis(benzimidazole-2'-yl)-pyridine (bzimpy) moiety has been successfully constructed via coordination-driven self-assembly. A study on the hierarchical self-assembly behavior of the obtained metallacage revealed that it displayed a solvent-induced emission switch accompanied by enhancement of the emission intensity as a result of the change in intermolecular Pt···Pt and π-π interactions. More interestingly, the metallacage has been found to spontaneously self-assemble into a transparent metallogel at room temperature without a heating-cooling process.

19.
Sensors (Basel) ; 18(1)2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286320

RESUMO

Vehicular nodes are equipped with more and more sensing units, and a large amount of sensing data is generated. Recently, more and more research considers cooperative urban sensing as the heart of intelligent and green city traffic management. The key components of the platform will be a combination of a pervasive vehicular sensing system, as well as a central control and analysis system, where data-gathering is a fundamental component. However, the data-gathering and monitoring are also challenging issues in vehicular sensor networks because of the large amount of data and the dynamic nature of the network. In this paper, we propose an efficient continuous event-monitoring and data-gathering framework based on fog nodes in vehicular sensor networks. A fog-based two-level threshold strategy is adopted to suppress unnecessary data upload and transmissions. In the monitoring phase, nodes sense the environment in low cost sensing mode and generate sensed data. When the probability of the event is high and exceeds some threshold, nodes transfer to the event-checking phase, and some nodes would be selected to transfer to the deep sensing mode to generate more accurate data of the environment. Furthermore, it adaptively adjusts the threshold to upload a suitable amount of data for decision making, while at the same time suppressing unnecessary message transmissions. Simulation results showed that the proposed scheme could reduce more than 84 percent of the data transmissions compared with other existing algorithms, while it detects the events and gathers the event data.

20.
Int J Mol Sci ; 18(4)2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28353642

RESUMO

Apoptosis (type I programmed cell death) of cardiomyocytes is a major process that plays a role in the progression of heart failure. The early response gene IER3 regulates apoptosis in a wide variety of cells and organs. However, its role in heart failure is largely unknown. Here, we investigate the role of IER3 in an inducible heart failure mouse model. Heart failure was induced in a mouse model that imitates a human titin truncation mutation we found in a patient with dilated cardiomyopathy (DCM). Transferase dUTP nick end labeling (TUNEL) and ssDNA stainings showed induction of apoptosis in titin-deficient cardiomyocytes during heart failure development, while IER3 response was dysregulated. Chromatin immunoprecipitation and knock-down experiments revealed that IER3 proteins target the promotors of anti-apoptotic genes and act as an anti-apoptotic factor in cardiomyocytes. Its expression is blunted during heart failure development in a titin-deficient mouse model. Targeting the IER3 pathway to reduce cardiac apoptosis might be an effective therapeutic strategy to combat heart failure.


Assuntos
Apoptose , Cardiomiopatia Dilatada/metabolismo , Conectina/genética , Proteínas Imediatamente Precoces/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Cardiomiopatia Dilatada/genética , Linhagem Celular , Proteínas Imediatamente Precoces/genética , Camundongos
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