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1.
J Am Chem Soc ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968086

RESUMO

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging the synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated the synthesis of a series of chiral functionalized cyclopropanes with high yield, enantioselectivity, and diastereoselectivity (44 examples, up to 93% yield and >99% ee). A possible reaction mechanism involving cyclopropene desymmetrization by Co-H species and imine addition by Co-alkyl species was proposed. This study provides a novel route to important chiral cyclopropanes and extends the frontier of asymmetric metallaphotoredox catalysis.

2.
Chemistry ; 30(32): e202400899, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38576216

RESUMO

An amphiphilic aza-BODIPY dye (S)-1 bearing two chiral hydrophilic side chains with S-stereogenic centers was synthesized. This dye exhibited kinetic-controlled self-assembly pathways and supramolecular chiral polymorphism properties in MeOH/H2O (9/1, v/v) mixed solvent. The (S)-1 monomers first aggregated into a kinetic controlled, off-pathway species Agg. A, which was spontaneously transformed into an on-pathway metastable aggregate (Agg. B) and subsequently into the thermodynamic Agg. C. The three aggregate polymorphs of dye (S)-1 displayed distinct optical properties and nanomorphologies. In particular, chiral J-aggregation characteristics were observed for both Agg. B and Agg. C, such as Davydov-split absorption bands (Agg. B), extremely sharp and intense J-band with large bathochromic shift (Agg. C), non-diminished fluorescence upon aggregation, as well as strong bisignated Cotton effects. Moreover, the AFM and TEM studies revealed that Agg. A had the morphology of nanoparticle while fibril or rod-like helical nanostructures with left-handedness were observed respectively for Agg. B and Agg. C. By controlling the kinetic transformation process from Agg. B to Agg. C, thin films consisting of Agg. B and Agg. C with different ratios were prepared, which displayed tunable CPL with emission maxima at 788-805 nm and g-factors between -4.2×10-2 and -5.1×10-2.

3.
J Craniofac Surg ; 35(4): e389-e391, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710063

RESUMO

Extranodal natural killer/T-cell lymphoma is a distinct subtype of non-Hodgkin lymphoma that originates from natural killer cells or cytotoxic T cells. Its diagnosis is challenging due to the rarity and lack of awareness, especially in cases where osteomyelitis of the jawbone is the initial symptom. This paper reports a case of extranodal natural killer/T-cell lymphoma presenting primarily with oral ulcers. Through analyzing the clinical and pathological characteristics, differential diagnosis, treatment and prognosis, and reasons for misdiagnosis of the disease, this study aims to provide references for clinical diagnosis and treatment.


Assuntos
Neoplasias do Seio Maxilar , Osteomielite , Humanos , Osteomielite/diagnóstico , Osteomielite/diagnóstico por imagem , Diagnóstico Diferencial , Neoplasias do Seio Maxilar/patologia , Neoplasias do Seio Maxilar/diagnóstico , Masculino , Linfoma Extranodal de Células T-NK/patologia , Linfoma Extranodal de Células T-NK/diagnóstico , Tomografia Computadorizada por Raios X , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/diagnóstico , Doenças Mandibulares/patologia , Úlceras Orais/diagnóstico , Úlceras Orais/patologia , Pessoa de Meia-Idade
4.
Angew Chem Int Ed Engl ; 63(19): e202402053, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38494439

RESUMO

Direct synthesis of dimethyl carbonate (DMC) from CO2 plays an important role in carbon neutrality, but its efficiency is still far from the practical application, due to the limited understanding of the reaction mechanism and rational design of efficient catalyst. Herein, abundant electron-enriched lattice oxygen species were introduced into CeO2 catalyst by constructing the point defects and crystal-terminated phases in the crystal reconstruction process. Benefitting from the acid-base properties modulated by the electron-enriched lattice oxygen, the optimized CeO2 catalyst exhibited a much higher DMC yield of 22.2 mmol g-1 than the reported metal-oxide-based catalysts at the similar conditions. Mechanistic investigations illustrated that the electron-enriched lattice oxygen can provide abundant sites for CO2 adsorption and activation, and was advantageous of the formation of the weakly adsorbed active methoxy species. These were facilitating to the coupling of methoxy and CO2 for the key *CH3OCOO intermediate formation. More importantly, the weakened adsorption of *CH3OCOO on the electron-enriched lattice oxygen can switch the rate-determining-step (RDS) of DMC synthesis from *CH3OCOO formation to *CH3OCOO dissociation, and lower the corresponding activation barriers, thus giving rise to a high performance. This work provides insights into the underlying reaction mechanism for DMC synthesis from CO2 and methanol and the design of highly efficient catalysts.

5.
J Am Chem Soc ; 145(12): 6944-6952, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36920031

RESUMO

Enantioselective metallaphotoredox catalysis, which combines photoredox catalysis and asymmetric transition-metal catalysis, has become an effective approach to achieve stereoconvergence under mild conditions. Although many impressive synthetic approaches have been developed to access central chirality, the construction of axial chirality by metallaphotoredox catalysis still remains underexplored. Herein, we report two visible light-induced cobalt-catalyzed asymmetric reductive couplings of biaryl dialdehydes to synthesize axially chiral aldehydes (60 examples, up to 98% yield, >19:1 dr, and >99% ee). This protocol shows good functional group tolerance, broad substrate scope, and excellent diastereo- and enantioselectivity.

6.
Chemistry ; 29(20): e202204060, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36622137

RESUMO

A series of side-chain liquid crystalline polymers P4VP(CN-DBE)x , where x is the molar ratio of cyanostilbene (CN-DBE) to poly(4-vinylpyridine) (P4VP) repeating unit, was synthesized based on the intermolecular hydrogen bonding between P4VP and CN-DBE. Their luminescent property, liquid crystalline structure and photo-thermo-electric property were elucidated using photoluminescence spectra, X-ray diffraction, thermal imaging and thermoelectric experiments. With the increase of x, the supramolecular system can be changed from lamellar structure to hexagonal columnar structure. Moreover, the P4VP(CN-DBE)x polymer with columnar structure exhibits more efficient photothermal effect. The temperature of P4VP(CN-DBE)0.6 can rise to 130 °C within 10 s under the irradiation of ultraviolet lamp. In addition, the supramolecular system possesses unique photo-thermo-electric conversion ability, and 25 mA current can be detected in the circuit coupled with the thermoelectric module. This work broadens the potential applications of hydrogen-bonded polymer, and provides a simple and facile strategy to prepare liquid crystalline polymers with photo-thermo-electric property.

7.
J Acoust Soc Am ; 153(5): 3151, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37255414

RESUMO

We present an iterative nonlinear inverse scattering algorithm for high-resolution acoustic imaging of density and velocity variations. To solve the multi-parameter nonlinear direct scattering problem, the acoustic wave equation for inhomogeneous media in the frequency domain is transformed into a vectorial integral equation of the Lippmann-Schwinger type for the combined pressure and pressure-gradient field. To solve the multi-parameter nonlinear inverse scattering problem, we use the Newton-Kantorovich method in conjunction with matrix-free representations of the Fréchet derivative operators and their adjoints. The approximate Hessian information that is accounted for in our iterative solution of the (nonlinear) multi-parameter inverse scattering problem is essential for the mitigation of multi-parameter cross talk effects. Numerical examples related to seismic and medical ultrasound breast imaging illustrate the performance of the new algorithm for multi-parameter acoustic imaging.

8.
Angew Chem Int Ed Engl ; 62(37): e202306786, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37470313

RESUMO

Although considerable efforts towards directly converting syngas to liquid fuels through Fischer-Tropsch synthesis have been made, developing catalysts with low CO2 selectivity for the synthesis of high-quality gasoline remains a big challenge. Herein, we designed a bifunctional catalyst composed of hydrophobic FeNa@Si-c and HZSM-5 zeolite, which exhibited a low CO2 selectivity of 14.3 % at 49.8 % CO conversion, with a high selectivity of 62.5 % for gasoline in total products. Molecular dynamic simulations and model experiments revealed that the diffusion of water molecules through hydrophilic catalyst was bidirectional, while the diffusion through hydrophobic catalyst was unidirectional, which were crucial to tune the water-gas shift reaction and control CO2 formation. This work provides a new fundamental understanding about the function of hydrophobic modification of catalysts in syngas conversion.

9.
Mutagenesis ; 36(4): 281-293, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34132814

RESUMO

Poly (ADP-ribose) polymerase-1 (PARP1), a DNA repair gene, is the crucial player in the maintenance of genome integrity. T2285C polymorphism in coding region of PARP1 has been reported to be associated with susceptibility to tumours. We explored the relationship and mechanism of T2285C polymorphism of PARP1 to its expression and activity along with risk and prognosis in non-small cell lung cancer (NSCLC). mRNA expression was measured using quantitative RT-PCR assay or collected from TCGA dataset. Protein expression was examined with immunoblotting assay. Genotypes were determined by PCR-RFLP and sequencing approaches. PARP1 activity was determined with enzyme activity assay. Regulation of SIRT7 to PARP1 was determined by overexpression and small interference experiment. Association of PARP1 T2285C polymorphism with NSCLC risk was evaluated via multiple logistic regression analysis. Comparison of treatment response and progression-free survival (PFS) of NSCLC patients among different genotypes or regimens was made by chi-square test. Results indicated that mRNA and protein expression of PARP1 dramatically increased in NSCLC tissues in comparison with paired para-carcinoma tissues (P < 0.05). TC/CC mutant genotypes were associated with markedly enhanced PARP1 mRNA level compared with TT genotype (P = 0.011). No significant difference was discovered in PARP1 protein expression among TT, TC or CC genotypes (P > 0.05). Subjects with variant allele C had higher risk of NSCLC in comparison with allele T carriers [odds ratio = 1.560; P = 0.000]. NSCLC patients carrying mutational TC or CC genotypes were correlated with unfavourable response to platinum-based chemotherapy (TT vs. TC vs. CC, P = 0.010), and shorter PFS compared with TT genotype (TT vs. TC vs. CC, P = 0.009). T2285C mutation of PARP1 resulted in the enhancement of its mRNA, but the decrease of enzyme activity in tumour cell. Overexpression of SIRT7 attenuated PARP1 expression and activity. These findings suggest the variant allele C of T2285C polymorphism of PARP1 linked to an increase of NSCLC risk, and unfavourable efficacy and prognosis of NSCLC patients with platinum-based chemotherapy, which might be associated with enhancement of its mRNA expression and the diminishment of activity. Identification of PARP1 T2285C polymorphism and mRNA expression may be the promising way for the individualised treatment of NSCLC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Poli(ADP-Ribose) Polimerase-1/genética , Polimorfismo de Nucleotídeo Único , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Poli(ADP-Ribose) Polimerase-1/metabolismo , Prognóstico , Risco , Sirtuínas
10.
Org Biomol Chem ; 19(27): 6108-6114, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34160530

RESUMO

A novel amphiphilic B,O-chelated azadipyrromethene (aza-BODIPY) dye, containing hydrophobic dodecyloxy groups and hydrophilic tetraethylene glycol (TEG) chains, was synthesized and characterized by NMR, HRMS, Vis/NIR absorption and fluorescence spectroscopy. The B,O-chelated dye 1 exhibited largely bathochromically shifted NIR absorption and fluorescence spectra in comparison with common BF2-chelated aza-BODIPY dyes. Upon gradual addition of trifluoroacetic acid (TFA) to the dye 1 solution, obvious spectral changes were observed in Vis/NIR absorption and fluorescence spectroscopy measurements. Meanwhile, the colour change of the dye 1 solution from pink to blue was noticeable by the naked eye, indicating the pH-sensitivity of dye 1. The pH-sensitivity of dye 1 under acidic conditions could be ascribed to the formation of dye species 2·H+. Furthermore, owing to the amphiphilic feature of dye 1, it self-assembled into J-type aggregates in a mixed solvent of water/DMSO (2/8, v/v). Temperature-dependent Vis/NIR spectroscopic studies revealed a cooperative aggregation process of dye 1 and a nanowire-like morphology of the nanoaggregates was observed by AFM.

11.
J Gastroenterol Hepatol ; 36(2): 474-481, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32677707

RESUMO

BACKGROUND AND AIM: Remimazolam tosilate (RT) is a new short-acting GABA(A) receptor agonist, having potential to be an effective option for procedural sedation. Here, we aimed to compare the efficacy and safety of RT with propofol in patients undergoing upper gastrointestinal endoscopy. METHODS: This positive-controlled, non-inferiority, phase III trial recruited patients at 17 centers, between September 2017 and November 2017. A total of 384 patients scheduled to undergo upper gastrointestinal endoscopy were randomly assigned to receive RT or propofol. Primary endpoint was the success rate of sedation. Adverse events (AEs) were recorded to evaluate safety. RESULTS: The success rate of sedation in the RT group was non-inferior to that in the propofol group (97.34% vs 100.00%; difference in rate -2.66%, 95% CI -4.96 to -0.36, meeting criteria for non-inferiority). Patients in the RT group had longer time to adequate sedation (P < 0.0001) but shorter time to fully alert (P < 0.0001) than that in the propofol group. The incidences of hypotension (13.04% vs 42.86%, P < 0.0001), treatment-related hypotension (0.54% vs 5.82%, P < 0.0001), and respiratory depression (1.09% vs 6.88%, P = 0.0064) were significantly lower in the RT group. AEs were reported in 74 (39.15%) patients in the RT group and 114 (60.32%) patients in the propofol group, with significant difference (P < 0.0001). CONCLUSION: This trial established non-inferior sedation success rate of RT compared with propofol. RT allows faster recovery from sedation compared with propofol. The safety profile is favorable and appears to be superior to propofol, indicating that it was feasible and well tolerated for patients.


Assuntos
Benzodiazepinas/administração & dosagem , Sedação Consciente/métodos , Endoscopia Gastrointestinal , Adulto , Idoso , Período de Recuperação da Anestesia , Benzodiazepinas/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Hipertensão/induzido quimicamente , Hipertensão/epidemiologia , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Incidência , Masculino , Pessoa de Meia-Idade , Propofol/administração & dosagem , Propofol/efeitos adversos , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/epidemiologia , Segurança
12.
Chem Soc Rev ; 49(9): 2546-2556, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32195482

RESUMO

Due to their inherent ring strain, three-membered carbocyclic- and heterocyclic ring structures are versatile synthetic building blocks. Traditional ring-opening methods of these molecules require the use of thermolysis, acid catalysts or transition-metals via ionic reaction pathways. Recently, visible light-induced photoredox catalysis has emerged as a powerful platform for initiating new chemical transformations. In this tutorial review, the synthetic and mechanistic aspects of visible light-promoted ring-opening functionalization of three-membered carbo- and heterocycles are highlighted. By using these strategies, a variety of ring-opening functionalization products, including biologically important carbo- and heterocycles, can be efficiently accessed in a high chemo- and regioselective manner.

13.
Molecules ; 26(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833936

RESUMO

An acyl radical generation and functionalization strategy through direct photoexcitation of benzothiazolines has been developed. The formed acyl radical species can either be trapped by quinoxalin-2-ones to realize their C(3)-H functionalization or trigger a cascade radical cyclization with isonitriles to synthesise biologically important phenanthridines. The synthetic value of this protocol can be further illustrated by the modification of quinoxalin-2-ones, containing important natural products and drug-based complex molecules.

14.
Stereotact Funct Neurosurg ; 98(2): 73-79, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32036377

RESUMO

INTRODUCTION: Stereoelectroencephalography (SEEG) refers to a commonly used diagnostic procedure to localise and define the epileptogenic zone of refractory focal epilepsies, by means of minimally invasive operation techniques without large craniotomies. OBJECTIVE: This study aimed to investigate the influence of different registration methods on the accuracy of SEEG electrode implantation under neuronavigation for paediatric patients with refractory epilepsy. METHODS: The clinical data of 18 paediatric patients with refractory epilepsy were retrospectively analysed. The SEEG electrodes were implanted under optical neuronavigation while the patients were in the prone position. Patients were divided into two groups on the basis of the surface-based registration of MR scan method and refined anatomy-based registration of CT scan. Registration time, accuracy, and the differences between electrode placement and preoperative planned position were analysed. RESULTS: Thirty-six electrodes in 7 patients were placed under surface-based registration of MR scan, and 45 electrodes in 11 patients were placed under refined anatomy-based registration of CT scan. The registration time of surface-based registration of MR scan and refined anatomy-based registration of CT scan was 45 ± 12 min and 10 ± 4 min. In addition, the mean registration error, the error of insertion point, and target error were 3.6 ± 0.7 mm, 2.7 ± 0.7 mm, and 3.1 ± 0.5 mm in the surface-based registration of MR scan group, and 1.1 ± 0.3 mm, 1.5 ± 0.5 mm, and 2.2 ± 0.6 mm in the refined anatomy-based registration of CT scan group. The differences between the two registration methods were statistically significant. CONCLUSIONS: The refined anatomy-based registration of CT scan method can improve the registration efficiency and electrode placement accuracy, and thereby can be considered as the preferred registration method in the application of SEEG electrode implantation under neuronavigation for treatment of paediatric intractable epilepsy.


Assuntos
Eletrodos Implantados/normas , Imageamento por Ressonância Magnética/normas , Neuronavegação/normas , Decúbito Ventral , Técnicas Estereotáxicas/normas , Tomografia Computadorizada por Raios X/normas , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neuronavegação/métodos , Decúbito Ventral/fisiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
15.
J Mater Sci Mater Med ; 31(12): 118, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33247778

RESUMO

Redox-responsive cationic polymers have gained considerable attention in gene delivery due to low cytotoxicity and spatio-temporal release of DNA into the cells. Here, we reported the synthesis of reducible disulfide conjugated polyethyleneimine (1.8 kDa) (denoted as SS-PEI) and its application to transfer pEGFP-ZNF580 plasmid (pZNF580) into EA.hy926 cell. This reducible SS-PEI polymer was prepared by one-step polycondensation reaction of low molecular weight PEI with bis-(p-nitrophenyl)-3,3'-dithiodipropionate. The SS-PEI successfully condensed pZNF580 into nano-sized complexes (170 ± 1.5 nm to 255 ± 1.6 nm) with zeta potentials of 3 ± 0.4 mV to 17 ± 0.9 mV. The complexes could be triggered to release pZNF580 when exposed to the reducing environment of 5 mM dithiothreitol. Besides, the SS-PEI exhibited low cytotoxicity. In vitro transfection results showed that SS-PEI exhibited good transfection efficiency comparable to PEI25kDa. Thus, the SS-PEI could act as an reducible gene carrier with good transfection efficiency and low cytotoxicity.


Assuntos
Dissulfetos/química , Técnicas de Transferência de Genes , Polietilenoimina/química , Células Cultivadas , DNA/química , Vetores Genéticos/química , Humanos , Oxirredução , Polímeros/química , Fatores de Transcrição/genética , Transfecção/métodos
16.
J Am Chem Soc ; 141(51): 19964-19968, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31804817

RESUMO

The efficient electrochemical hydrogen evolution reaction (HER) plays a key role in accelerating sustainable H2 production from water electrolysis, but its large-scale applications are hindered by the high cost of the state-of-the-art Pt catalyst. In this work, submonolayer Pt was controllably deposited on an intermetallic Pd3Pb nanoplate (AL-Pt/Pd3Pb). The atomic efficiency and electronic structure of the active surface Pt layer were largely optimized, greatly enhancing the acidic HER. AL-Pt/Pd3Pb exhibits an outstanding HER activity with an overpotential of only 13.8 mV at 10 mA/cm2 and a high mass activity of 7834 A/gPd+Pt at -0.05 V, both largely surpassing those of commercial Pt/C (30 mV, 1486 A/gPt). In addition, AL-Pt/Pd3Pb shows excellent stability and robustness. Theoretical calculations show that the improved activity is mainly derived from the charge transfer from Pd3Pb to Pt, resulting in a strong electrostatic interaction that can stabilize the transition state and lower the barrier.

17.
Macromol Rapid Commun ; 40(12): e1800916, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30990950

RESUMO

Multifunctional carriers with both gene transfection property and fluorescent tracking function have attracted significant attention in recent years. Herein, a kind of perylene diimide derivative (PDI-C10C8) is conjugated onto the polyethylenimine-g-poly(lactide-co-glycolide)-g-polyethylenimine (PLGA-PEI) polymer to obtain fluorescent multifunctional polymer and micelles (abbreviated as MP). Then, the REDV-G-TAT-G-NLS (TP-G) peptide sequence is grafted onto this MP to obtain multifunctional micelles labeled by perylene diimide derivative (MP-TP-G). These micelles exhibit enhanced photobleaching stability compared with the reference Cy5-labeled micelles, and the fluorescent images of cellular uptake show bright red emission without any background noise. Confocal laser scanning microscope (CLSM) experiments show that gene complexes can deliver gene into nucleus. MP-TP-G carriers do not enter into the cell nucleus, which proves that the nuclear localization signal sequence may not exert its nucleus accumulation ability via conjugating to the amphiphilic polymers. The high transfection efficiency and the enhanced photobleaching stability, combined with the ability to monitor the detailed process of cellular uptake and gene delivery, make these multifunctional micelles have great potential application for endothelialization of artificial blood vessels and gene delivery process study.


Assuntos
Corantes Fluorescentes/química , Técnicas de Transferência de Genes , Imidas/química , Perileno/química , Células Endoteliais/citologia , Humanos , Micelas , Polímeros/química
18.
Sensors (Basel) ; 19(12)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31207984

RESUMO

Due to the flexible and compact structures, spherical joints are widely used in parallel manipulators and industrial robots. Real-time detection of the clearance between the ball and the socket in spherical joints is beneficial to compensate motion errors of mechanical systems and improve their transmission accuracy. This work proposes an improved capacitive sensor for detecting the micro-clearance of spherical joints. First, the structure of the capacitive sensor is proposed. Then, the mathematical model for the differential capacitance of the sensor and the eccentric micro-displacement of the ball is deduced. Finally, the capacitance values of the capacitive sensor are simulated with Ansoft Maxwell. The simulated values of the differential capacitances at different eccentric displacements agree well with the theoretical ones, indicating the feasibility of the proposed detection method. In addition, the simulated results show that the proposed capacitive sensor could effectively reduce the capacitive fringe effect, improving the measurement accuracy.

19.
Molecules ; 24(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167411

RESUMO

In this article, we report the facile synthesis, self-assembly, and characterization of shape amphiphiles (BPOSS-PDI-X) based on isobutyl-functionalized polyhedral oligomeric silsesquioxane (BPOSS), perylene tetracarboxylic diimide (PDI), and (60)fullerene (C60) moieties. Firstly, an asymmetrically functionalized diblock shape amphiphile precursor (BPOSS-PDI-OH) was obtained through the one-pot reaction between perylene-3,4,9,10-tetracarboxylic dianhydride and two different amines, namely BPOSS-NH2 and 3-amino-1-propanol. It was further conjugated with C60-COOH to give a tri-block shape amphiphile (BPOSS-PDI-C60). Their chemical structures were thoroughly characterized by NMR, IR and MALDI-TOF MS spectrometry. In order to gain insights on the structure-property relationship, their self-assembly in gas phase, in solution, and in solid state were characterized using traveling wave ion mobility mass spectrometry (TWIM-MS), UV/Vis absorption, fluorescence emission spectrophotometer, and transmission electron microscopy, respectively. It was found that BPOSS-PDI-OH formed more complicated dimers than BPOSS-PDI-C60. Both samples showed unique aggregation behaviors in solution with increasing concentration, which could be attributed neither to H- nor to J-type and might be related to the discrete dimers. While BPOSS-PDI-C60 could hardly crystalize into ordered structures, BPOSS-PDI-OH could form nanobelt-shaped single crystals, which may hold potential applications in microelectronics.


Assuntos
Fulerenos/química , Imidas/química , Perileno/análogos & derivados , Tensoativos/química , Cristalinas/química , Cristalinas/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nanoestruturas , Perileno/química , Espectrometria de Massas por Ionização por Electrospray/métodos
20.
J Cell Biochem ; 119(6): 4692-4710, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29278662

RESUMO

This study aims to investigate the effects of microRNA-335-5p (miR-335-5p) on lower-extremity deep vein thrombosis (LEDVT) by targeting PAI-1 through the TLR4 signaling pathway in rat models. siRNA, mimic, and inhibitor were used for transfection. The miR-335-5p expression was detected by in situ hybridization. CCK-8 assay and flow cytometry were adopted to detect proliferation, cell cycle, and apoptosis, respectively. Scratch test and Matrigel-based tube formation assay were used to detect the effect of miR-335-5p on cell migration ability and tube formation ability. A miR-335-5p lentivirus plasmid was constructed and injected into LEDVT rats. The length and weight of thrombus were measured, changes of thrombus recanalization were observed by CD34 immunohistochemistry, and levels of PAI-1 and inflammatory factors in femoral vein blood were detected by ELISA. LEDVT rats showed a higher AOD value of PAI-1, higher expression of PAI-1, NF-κB, Rac1, IL-1ß, and TLR4 and a lower miR-335-5p expression. PAI-1 and miR-335-5p were negatively correlated. Compared to the blank and siRNA-NC groups, the miR-335-5p mimic and siRNA-PAI-1 groups showed declined expression of PAI-1, TLR4, NF-κB, Rac1, and IL-1ß, increased proliferation and tube formation abilities, less cells in G0/G1 phase, and decreased apoptosis, decreased length and weight of thrombus, organized thrombus, increased new blood vessels, and decreased levels of PAI-1, IL-1, IL-6, and Tnf-a. miR-335-5p may suppress the occurrence and development of LEDVT in rats by repressing the activation of the TLR4 signaling pathway by targeted inhibition of PAI-1.


Assuntos
Membro Posterior/irrigação sanguínea , MicroRNAs/metabolismo , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Trombose Venosa/metabolismo , Animais , Feminino , Fase G1 , Regulação da Expressão Gênica , Membro Posterior/metabolismo , Membro Posterior/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Fase de Repouso do Ciclo Celular , Trombose Venosa/patologia
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