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1.
Nucleic Acids Res ; 51(D1): D39-D45, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36268869

RESUMO

Transcription factors (TFs) are proteins that interact with specific DNA sequences to regulate gene expression and play crucial roles in all kinds of biological processes. To keep up with new data and provide a more comprehensive resource for TF research, we updated the Animal Transcription Factor Database (AnimalTFDB) to version 4.0 (http://bioinfo.life.hust.edu.cn/AnimalTFDB4/) with up-to-date data and functions. We refined the TF family rules and prediction pipeline to predict TFs in genome-wide protein sequences from Ensembl. As a result, we predicted 274 633 TF genes and 150 726 transcription cofactor genes in AnimalTFDB 4.0 in 183 animal genomes, which are 86 more species than AnimalTFDB 3.0. Besides double data volume, we also added the following new annotations and functions to the database: (i) variations (including mutations) on TF genes in various human cancers and other diseases; (ii) predicted post-translational modification sites (including phosphorylation, acetylation, methylation and ubiquitination sites) on TFs in 8 species; (iii) TF regulation in autophagy; (iv) comprehensive TF expression annotation for 38 species; (v) exact and batch search functions allow users to search AnimalTFDB flexibly. AnimalTFDB 4.0 is a useful resource for studying TF and transcription regulation, which contains comprehensive annotation and classification of TFs and transcription cofactors.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica , Fatores de Transcrição , Animais , Humanos , Bases de Dados de Proteínas , Anotação de Sequência Molecular , Fatores de Transcrição/metabolismo
2.
Chem Soc Rev ; 52(4): 1215-1272, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36601686

RESUMO

Together with the development of two-dimensional (2D) materials, transition metal dichalcogenides (TMDs) have become one of the most popular series of model materials for fundamental sciences and practical applications. Due to the ever-growing requirements of customization and multi-function, dozens of modulated structures have been introduced in TMDs. In this review, we present a systematic and comprehensive overview of the structure modulation of TMDs, including point, linear and out-of-plane structures, following and updating the conventional classification for silicon and related bulk semiconductors. In particular, we focus on the structural characteristics of modulated TMD structures and analyse the corresponding root causes. We also summarize the recent progress in modulating methods, mechanisms, properties and applications based on modulated TMD structures. Finally, we demonstrate challenges and prospects in the structure modulation of TMDs and forecast potential directions about what and how breakthroughs can be achieved.

3.
J Sci Food Agric ; 103(4): 1964-1973, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36533998

RESUMO

BACKGROUND: In this study, a new crosslinking agent (CA) containing whey protein, papin, glycerin, and epigallocatechin gallate (EGCG), was prepared. The effects of CA content (0, 10, 20, 30, and 40%, v/v) on food packaging properties, crystallinity, microstructure, and antioxidant properties of pectin-CA and chitosan-CA composite films were analyzed. The results of this research offer a theoretical basis for engineering improved films for food packing. RESULTS: Pectin-CA (30%) and chitosan-CA (40%) composite films showed the best light transmission, water retention, breathability, plasticity, and antioxidant activity. Scanning electron microscopy revealed that these composite films exhibited a uniform and homogeneous structure without obvious pores. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) indicated that the amino acids and EGCG in CA were bonded to the film substrate (pectin/chitosan) via electrostatic interactions, hydrogen bonding, and covalent bonding, which led to an improvement in the film's properties. CONCLUSION: The CA has broad application prospects in food packaging as a cross-linking agent and antioxidant. © 2022 Society of Chemical Industry.


Assuntos
Quitosana , Quitosana/química , Antioxidantes/química , Pectinas/química , Difração de Raios X , Embalagem de Alimentos/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Sci Food Agric ; 103(15): 7798-7808, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37463295

RESUMO

BACKGROUND: This study developed an intelligent, pH-sensitive and amine-responsive colorimetric label based on chitosan, whey protein and thymol blue by controlling the pH value of the film-forming solution. The obtained label was used to monitor shrimp freshness in real time. The results of this study offer a new approach for developing highly intelligent biogenic labels for freshness monitoring during seafood preservation and processing. RESULTS: The pH 2.0 chitosan-whey protein-thymol blue (CWT-pH 2.0) label exhibited remarkable properties, including the highest tensile strength (5.90 MPa), excellent thermal stability, low water solubility (27.80%) and highly sensitive color responsiveness. The characterization techniques of scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy confirmed the effective immobilization of thymol blue within the film-forming matrix through hydrogen bonding. Furthermore, the CWT-pH 2.0 label demonstrated visible color changes in the presence of volatile ammonia concentrations ranging from 25 to 25 000 ppm. Consequently, the label successfully facilitated real-time monitoring of shrimp freshness during storage at 4 °C. Importantly, the release rate of thymol blue from the label in food simulants was minimal, measuring only 2.53%. CONCLUSION: The CWT-pH 2.0 label exhibits significant potential as a highly intelligent biogenic label for freshness monitoring in seafood preservation and processing. © 2023 Society of Chemical Industry.


Assuntos
Quitosana , Quitosana/química , Aminas , Proteínas do Soro do Leite , Alimentos Marinhos/análise , Concentração de Íons de Hidrogênio , Antocianinas/química , Embalagem de Alimentos/métodos
5.
Anal Chem ; 94(22): 7861-7867, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35603578

RESUMO

Since aggregation-induced electrochemiluminescence (AIECL) combined the merits of aggregation-induced emission (AIE) and electrochemiluminescence (ECL), it has become a research hotspot recently. Herein, novel kinds of functional metal-organic frameworks (MOFs) with strong AIECL were reported through doping tetraphenylethylene (TPE) into UiO-66. Due to the porosity and highly ordered topological structure that caused the confinement effect of MOFs, the molecular motion of TPE was effectively limited within UiO-66, resulting in strong AIE. Meanwhile, the large specific surface area and porous structure of UiO-66 allowed TPE to react with coreactants more effectively, which was beneficial to ECL. Thus, the TPE-functionalized UiO-66 (TPE-UiO-66) showed excellent AIECL performance surprisingly. Inspired by this, a multiple convertible ECL resonance energy transfer (ECL-RET) system was constructed through a DNA Y structure that regulated the distance between the energy donor (TPE-UiO-66) and different energy acceptors (gold nanoparticles and Adriamycin). Furthermore, an ultrasensitive ECL biosensor for the detection of Mucin 1 (MUC1) was developed through the introduction of the novel ECL-RET system. In the presence of MUC1, the DNA Y structure was constructed, keeping the gold nanoparticles (AuNPs) away from TPE-UiO-66. Then, Adriamycin (Dox) could be embedded in the DNA Y structure and act as an energy acceptor to receive the energy of TPE-UiO-66, which made the biosensor produce a strong ECL response. As expected, the developed ECL biosensor exhibited superior detection performance for MUC1. This work provided a novel way to realize AIECL and board the application of AIECL in analytical chemistry.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , Técnicas Biossensoriais/métodos , DNA , Doxorrubicina , Técnicas Eletroquímicas/métodos , Transferência de Energia , Ouro/química , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Ácidos Ftálicos , Estilbenos
6.
Anal Chem ; 94(40): 13719-13727, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36173369

RESUMO

Based on the Venturi self-pumping effect, real-time sniffing with mass spectrometry (R-sniffing MS) is developed as a tool for direct and real-time mass spectrometric analysis of both gaseous and solid samples. It is capable of dual-mode operation in either gaseous or solid phase, with the corresponding techniques termed as Rg-sniffing MS and Rs-sniffing MS, respectively. In its gaseous mode, Rg-sniffing MS is capable of analyzing a gaseous mixture with response time (0.8-2.1 s rise time and 7.3-9.6 s fall time), spatial resolution (<80 µm), three-dimensional diffusion imaging, and aroma distribution imaging of red pepper. In its solid mode, an appropriate solvent droplet desorbs the sample from a solid surface, followed by the aspiration of the mixture using the Venturi self-pumping effect into the mass spectrometer, wherein it is ionized by a standard ion source. Compared with the desorption electrospray ionization (DESI) technique, Rs-sniffing MS demonstrated considerably improved limit of detection (LOD) values for arginine (0.07 µg/cm2 Rs-sniffing vs 1.47 µg/cm2 DESI), thymopentin (0.10 µg/cm2 vs 2.67 µg/cm2), and bacitracin (0.16 µg/cm2 vs 2.28 µg/cm2). Rs-sniffing is applicable for the detection of C60(OCH3)6Cl-, an intermediate in the methoxylation reaction involving C60Cl6 (solid) and methanol (liquid). The convenient and highly sensitive R-sniffing MS has a characteristic separation of desorption from the ionization process, in which the matrix atmosphere of desorption can be interfaced by a pipe channel and self-pumped by the Venturi effect with consequent integration using a standard ion source. The R-sniffing MS operates in a voltage-, heat-, and vibration-free environment, wherein the analyte is ionized by a standard ion source. Consequently, a wide range of samples can be analyzed simultaneously by the R-sniffing MS technique, regardless of their physical state.


Assuntos
Gases , Espectrometria de Massas por Ionização por Electrospray , Arginina , Bacitracina , Metanol , Solventes , Espectrometria de Massas por Ionização por Electrospray/métodos , Timopentina
7.
Anal Chem ; 93(25): 8791-8798, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34125511

RESUMO

Programmed cell death protein 1 (PD-1) is one of the coinhibitory checkpoints upon T cell activation, the abnormal expression of which severely threatens host immune modulatation for chronic infection. Thus, fast and sensitive monitoring of PD-1 is of vital importance for early diagnosis and cancer treatment. The current detection methods largely based on enzyme-linked immunosorbent assay (ELISA) require time-consuming incubation and complicated washing steps. Herein, we designed a simple and portable nanofiber paper (NFP)-based fluorescence "off-on" immunosensor for PD-1 rapid determination. Molybdenum disulfide (MoS2) nanosheets modified NFP (MoS2-NFP) was employed for adsorbing and immobilizing CdSe/ZnS quantum dots-antibody (QDs-Ab) complex to construct a ready-to-use fluorescent immunosensor. The fluorescent signal of QDs-Ab was initially quenched by MoS2 under the Förster resonance energy transfer (FRET) effect. When the PD-1 target was specifically captured onto NFP by immunization, the QDs-Ab-PD-1 complex was promptly desorbed from the MoS2-NFP surface, resulting in FRET impediment and fluorescence recovery. As an alternative quenching agent, graphene oxide (GO) served as a contrast to investigate NFP-based sensing performance. Owing to superior quenching and desorption efficiency, the MoS2-NFP-based fluorescence immunosensor exhibited nearly 2-fold lower detection limit (85.5 pg/mL) than GO-NFP-based sensor (151 pg/mL) for PD-1 monitoring. Excellent selectivity and satisfactory recovery in PD-1 mouse cell culture supernatant samples were confirmed as well. In addition, the comparable detectability of the MoS2-NFP-based immunosensor was accurately evaluated by a standard PD-1 mouse ELISA kit. This study displayed a simple, rapid, low-cost, and portable point-of-care PD-1 assay, indicating its broad application prospect toward clinical diagnoses.


Assuntos
Técnicas Biossensoriais , Nanofibras , Pontos Quânticos , Animais , Dissulfetos , Imunoensaio , Limite de Detecção , Camundongos , Molibdênio , Sistemas Automatizados de Assistência Junto ao Leito , Receptor de Morte Celular Programada 1
8.
Anal Chem ; 93(18): 7102-7109, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33908770

RESUMO

Effective acquirement of highly pure circulating tumor cells (CTCs) is very important for CTC-related research. However, it is a great challenge since abundant white blood cells (WBCs) are always co-collected with CTCs because of nonspecific bonding or low depletion rate of WBCs in various CTC isolation platforms. Herein, we designed a three-dimensional (3D) conductive scaffold microchip for highly effective capture and electrochemical release of CTCs with high purity. The conductive 3D scaffold was prepared by dense immobilization of gold nanotubes (Au NTs) on porous polydimethylsiloxane and was functionalized with a CTC-specific biomolecule facilitated by a Au-S bond before embedding into a microfluidic device. The spatially distributed 3D macroporous structure compelled cells to change migration from linear to chaotic and the densely covered Au NTs enhanced the topographic interaction between cells and the substrate, thus synergistically improving the CTC capture efficiency. The Au NT-coated 3D scaffold had good electrical conductivity and the Au-S bond was breakable by voltage exposure so that captured CTCs could be specifically released by electrochemical stimulation while nonspecifically bonded WBCs were not responsive to this process, facilitating recovery of CTCs with high purity. The 3D conductive scaffold microchip was successfully applied to obtain highly pure CTCs from cancer patients' blood, benefiting the downstream analysis of CTCs.


Assuntos
Células Neoplásicas Circulantes , Contagem de Células , Linhagem Celular Tumoral , Separação Celular , Condutividade Elétrica , Humanos , Dispositivos Lab-On-A-Chip , Análise em Microsséries
9.
Brain Behav Immun ; 95: 310-320, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33838249

RESUMO

Complement pathway over-activation has been implicated in a variety of neurological diseases. However, the signaling pathways governing astrocytic complement activation in Parkinson's disease (PD) are poorly understood. Kir6.1, a pore-forming subunit of ATP-sensitive potassium (K-ATP) channel, is prominently expressed in astrocytes and exhibits anti-inflammatory effects. Therefore, we hypothesize that Kir6.1/K-ATP channel may regulate astrocytic complement activation in the pathogenesis of PD. In this study, astrocytic Kir6.1 knockout (KO) mice were used to examine the effect of astrocytic Kir6.1/K-ATP channel on astrocytic complement activation triggered by the lipopolysaccharide (LPS). Here, we found that astrocytic Kir6.1 KO mice showed more dopaminergic neuron loss and more astrocyte reactivity in substantia nigra compacta than controls. We also found that astrocytic Kir6.1 KO increased the expression of complement C3 in astrocytes in LPS-induced mouse model of PD. Mechanistically, astrocytic Kir6.1 KO promoted astroglial NF-κB activation to elicit extracellular release of C3, which in turn interacted with neuronal C3aR to induce neuron death. Blocking complement function by NF-κB inhibitor or C3aR antagonist rescued the aggravated neuron death induced by Kir6.1 KO. Collectively, our findings reveal that astrocytic Kir6.1/K-ATP channel prevents neurodegeneration in PD via astrocyte-neuron cross talk through NF-κB/C3/C3aR signaling and suggest that targeting astroglial Kir6.1/K-ATP channel-NF-κB-C3-neuronal C3aR signaling represents a novel therapeutic strategy for PD.


Assuntos
Astrócitos , Canais KATP/genética , Doença de Parkinson , Animais , Complemento C3/metabolismo , Deleção de Genes , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios , Receptores de Complemento/metabolismo
10.
Anal Chem ; 92(7): 5447-5455, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32162513

RESUMO

Current strategies for in vitro isolation of circulating tumor cells (CTCs) fail to detect extremely rare CTCs heterogeneously distributed in blood. It is possible to devise methods for in vivo capture of CTCs based on processing almost all of the blood in the human body to improve detection sensitivity, but the complicated manipulation, biosafety concerns, and limited capture efficiency of conventional detection strategies prohibit their implementation in the clinic. Herein, we present a flexible three-dimensional (3-D) CTC-Net probe for intravascular collection of CTCs. The CTC-Net, consisting of a 3-D elastic scaffold with an interconnected, spatially distributed network accommodates a large quantity of immobilized antibodies and provides an enhanced substrate-cell contact frequency, which results in an enhanced capture efficiency and effective detection of heterogeneous CTCs. The as-prepared CTC-Net can be readily compressed and injected into blood vessels and fully unfolded to form a 3-D "fishing-net" structure for capture of the CTCs, and then retracted for imaging and downstream gene analysis of the captured CTCs. Significant advantages for the CTC-Net over currently available in vitro and in vivo procedures are demonstrated for detection of extremely rare CTCs from wild-type rats and successful capture of CTCs and CTC clusters before metastasis in the case of tumor-bearing rats. Our research demonstrates for the first time the use of a 3-D scaffold CTC-Net probe for in vivo capture of CTCs. The method shows exceptional performance for cell capture, which is readily implemented and holds great potential in the clinic for early diagnosis of cancer.


Assuntos
Vasos Sanguíneos/patologia , Separação Celular/instrumentação , Fenômenos Mecânicos , Células Neoplásicas Circulantes/patologia , Animais , Elasticidade , Humanos , Células MCF-7 , Ratos
11.
J Insect Sci ; 20(3)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32396202

RESUMO

A large number of ecdysteroid-regulated 16 kDa proteins (ESR16s) of insects have been isolated and annotated in GenBank; however, knowledge on insect ESR16s remain limited. In the present study, we characterized an ecdysteroid-regulated 16 kDa protein gene isolated in Chinese oak silkworm, Antheraea pernyi Guérin-Méneville ('ApESR16' in the following), an important silk-producing and edible insect. The obtained cDNA sequence of ApESR16 is 1,049 bp, harboring an open reading frame of 441 bp that encodes a polypeptide of 146 amino acids. CD-search revealed that ApESR16 contains the putative cholesterol/lipid binding sites on conserved domain Npc2_like (Niemann-Pick type C-2) belonging to the MD-2-related lipid-recognition superfamily. Sequence comparison revealed that ApESR16 exhibits 51-57% identity to ESR16s of lepidopteran insects, 36-41% identity to ESR16 or NPC2a of nonlepidopteran insects, and 28-32% identity to NPC2a of vertebrates, indicating a high sequence divergence during the evolution of animals. Phylogenetic analysis found that the used sequences were divided into two groups corresponding to vertebrates and invertebrates, and the used insect sequences were also well clustered according to their families. The A. pernyi ESR16 mRNA is expressed during all four developmental stages and in all tested tissues. Injection of 20-hydroxyecdysone (20-E) into A. pernyi diapausing pupae triggering diapause termination induced upregulation of ESR16 mRNA compared to the diapausing pupae, with the highest expression level at day 2 in the ovaries but day 12 in the fat body. Our results suggested that ApESR16 might be a diapause-related gene and plays a vital role in the pupal diapause of A. pernyi.


Assuntos
Ecdisteroides/metabolismo , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Mariposas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Masculino , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Filogenia , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Alinhamento de Sequência
12.
J Am Chem Soc ; 141(16): 6651-6657, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30879294

RESUMO

The combustion has long been applied for industrial synthesis of carbon materials such as fullerenes as well as carbon particles (known as carbon black), but the components and structures of the carbon soot are far from being clarified. Herein, we retrieve an unprecedented hydrofullerene C66H4 from a soot of a low-pressure combustion of benzene-acetylene-oxygen. Unambiguously characterized by single-crystal X-ray diffraction, the C66H4 renders a nonclassical geometry incorporating two heptagons and two pairs of fused pentagons in a C2 v symmetry. The common vertexes of the fused pentagons are bonded with four hydrogen atoms to convert the hydrogen-linking carbon atoms from sp2 to sp3 hybridization, which together with the adjacent heptagons essentially releases the sp2-bond strains on the abutting-pentagon sites of the diheptagonal fused pentagon C66 (dihept-C66). DFT computations suggest the possibility for an in situ hydrogenation process leading to stabilization of the dihept-C66. In addition, the experiments have been carried out to study heptagon-dependent properties of dihept-C66H4, indicating the key responsibility of the heptagon for changing hydrocarbon activity and electronic properties. The present work with the unprecedented double-heptagon-containing hydrofullerene successfully isolated and identified as one of the low-pressure combustion products shows that the heptagon is a new building block for constructing fullerene products in addition to pentagons and hexagons in low-pressure combustion systems.

13.
Analyst ; 144(8): 2550-2555, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30865739

RESUMO

In this study, an ultrasensitive electrochemiluminescence (ECL) aptasensor based on Ru(bpy)32+-doped silica nanoparticles (Ru@SiO2 NPs) coupled with gold nanoparticles (Au NPs) was developed for the determination of ractopamine (Rac). TPrA is used as the coreactant, the Ru@SiO2 NPs serve as the ECL luminophores, and the Au NPs work as a catalyzer in the redox reaction as well as the carrier that immobilizes the aptamer. Meanwhile, the complete incorporation of the Ru@SiO2 NPs and Au NPs increases the localized surface plasmon resonance (LSPR) probability, thus promoting ECL emission. The ractopamine (Rac) target molecules are specifically captured on the electrode surface by aptamer recognition. The ECL signal is quenched by energy transfer from the luminophore to benzoquinone compounds, which are oxidative products of Rac from the electrochemical scanning process. The proposed ECL aptasensor exhibits ultrahigh sensitivity and excellent selectivity for Rac detection. The linear response ranged over Rac concentrations from 1.5 × 10-12 M to 1.5 × 10-8 M with a detection limit of 4.1 × 10-14 M (S/N = 3). The detection recovery of Rac in real meat samples confirmed the satisfactory performance of the method. This study describes a versatile ECL aptasensor based on the combined functions of luminous nanospheres and Au NPs, indicating its potential application for the ultrasensitive analysis of targets in diverse systems.

14.
Anal Chem ; 90(8): 5075-5081, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29595051

RESUMO

Electrochemiluminescence (ECL) detection has attracted increasing attention as a promising analytical approach. A considerable number of studies showed that ECL intensity can be definitely improved by resonance energy transfer (RET), while the RET efficiency is strongly dependent on the distance between exited donors and acceptors. Herein we disclose for the first time a highly enhanced RET strategy to promote the energy transfer efficiency by coencapsulating the donor ([Ru(bpy)3]2+)/acceptor (CdTe quantum dots, CdTe QDs) pairs into a silica nanosphere. Plenty of [Ru(bpy)3]2+ and CdTe QDs closely packed inside a single nanosphere greatly shortens the electron-transfer path and increases the RET probability, therefore significantly enhancing the luminous efficiency. Further combining with molecularly imprinting technique, we develop a novel ECL sensor for ultrasensitive and highly selective detection of target molecules. Proof of concept experiments showed that extremely low detection limits of subfg/mL (S/N = 3) with broad linear ranges (fg/mL to ng/mL) could be obtained for detection of two kinds of mycotoxins (α-ergocryptine and ochratoxin A) that are recognized as potential health hazards at very low concentrations. This strategy combining enhanced RET system and molecularly imprinting technique, represents a versatile ECL platform toward low-cost, rapid, ultrasensitive, and highly selective detection of target molecules in diverse applications.

15.
J Pharmacol Exp Ther ; 364(3): 367-376, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298819

RESUMO

To investigate the role of histamine N-methyltransferase (HNMT) activity in the development of motion sickness (MS) in the dorsal vagal complex (DVC) to inform the development of new drugs for MS, Beagle dogs and Sprague-Dawley rats were rotated to simulate MS. HNMT expression in the brain stem and DVC was measured. The effects of systemic application of tacrine, an HNMT inhibitor, on the development of MS were observed. Moreover, we microinjected a histamine receptor H1 inhibitor, promethazine, into the DVC to verify the involvement of histaminergic neurotransmission in MS. Finally, lentiviral vectors were microinjected into the DVC to determine the effects of altered HNMT expression on MS. We found the following: 1) HNMT expression in the medulla oblongata of dogs and rats insusceptible to MS was higher than in susceptible animals; 2) tacrine dose-dependently promoted MS in both animals and raised histamine level in rat medulla oblongata; 3) blocking histaminergic neurotransmission in the DVC with promethazine inhibited MS; 4) rotatory stimulus induced an elevation in HNMT expression, and vestibular training elevated the basal level of HNMT in the DVC during habituation to MS; 5) in vivo transfection of a lentiviral vector packaged with the HNMT gene increased HNMT expression in the DVC and reduced MS; and 6) microinjection of a lentiviral vector driving the interference of HNMT gene expression in vivo significantly inhibited HNMT expression in the DVC and exacerbated MS. In conclusion, HNMT expression in the brain stem is inversely correlated with MS development. Increasing HNMT expression or stimulating its activity in the DVC could inhibit MS.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Histamina N-Metiltransferase/metabolismo , Terapia de Alvo Molecular , Enjoo devido ao Movimento/tratamento farmacológico , Enjoo devido ao Movimento/enzimologia , Nervo Vago/efeitos dos fármacos , Animais , Cães , Feminino , Histamina/metabolismo , Masculino , Enjoo devido ao Movimento/metabolismo , Ratos , Ratos Sprague-Dawley , Nervo Vago/metabolismo
16.
Org Biomol Chem ; 16(34): 6284-6294, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30116808

RESUMO

An efficient palladium-catalyzed ortho-aroylation of O-arylmethyl and aryl-substituted acetoxime ethers has been developed; this method has high mono-site selectivity and does not require exogenous ligands. Under the direction of a simple exo-acetoxime auxiliary, a broad scope of masked arylmethyl alcohols and phenols as well as various aromatic aldehydes are compatible with this transformation, which probably follows a mechanistic pathway involving a six- or five-membered exo-cyclopalladated intermediate. The strategy can be expediently adopted to prepare synthetically valuable 1H-benzo[d][1,2]oxazines and benzo[d]isoxazoles. The directing group can be easily removed from the products to afford the functionalized diaryl ketones.

17.
Angew Chem Int Ed Engl ; 56(32): 9454-9458, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28636246

RESUMO

Existing methods offer little direct and real-time information about stretch-triggered biochemical responses during cell mechanotransduction. A novel stretchable electrochemical sensor is reported that takes advantage of a hierarchical percolation network of carbon nanotubes and gold nanotubes (CNT-AuNT). This hybrid nanostructure provides the sensor with excellent time-reproducible mechanical and electrochemical performances while granting very good cellular compatibility, making it perfectly apt to induce and monitor simultaneously transient biochemical signals. This is validated by monitoring stretch-induced transient release of small signaling molecules by both endothelial and epithelial cells cultured on this sensor and submitted to stretching strains of different intensities. This work demonstrates that the hybrid CNT-AuNT platform offers a versatile and highly sensitive way to characterize and quantify short-time mechanotransduction responses.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro/química , Células Endoteliais da Veia Umbilical Humana/química , Mecanotransdução Celular , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Óxido Nítrico/biossíntese , Óxido Nítrico/química , Óxido Nítrico Sintase Tipo III/metabolismo , Tamanho da Partícula , Fatores de Tempo
18.
J Am Chem Soc ; 138(30): 9629-33, 2016 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-27377559

RESUMO

Curvature prevalently exists in the world of carbon materials (e.g., fullerenes, buckyl bowls, carbon nanotubes, and onions), but traditional C2-addition mechanisms fail to elucidate the mechanism responsible for the formation of carbon curvature starting from a pentagonal carbon ring in currently available chemical-physical processes such as combustion. Here, we show a complete series of nascent pentagon-incorporating C5-C18 that are online produced in the flame of acetylene-cyclopentadiene-oxygen and in situ captured by C60 or trapped as polycyclic aromatic hydrocarbons for clarifying the growth of the curved subunit of C20H10. A mechanism regarding C1-substitution and C2-addition has been proposed for understanding the formation of curvature in carbon materials, as exemplified by the typical curved molecule containing a single pentagon completely surrounded by five hexagons. The present mechanism, supported by the intermediates characterized by X-ray crystallography as well as NMR, has been experimentally validated for the rational synthesis of curved molecule in the commercially useful combustion process.

19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(8): 929-932, 2016 08.
Artigo em Zh | MEDLINE | ID: mdl-30640986

RESUMO

Objective To observe distribution laws and features of syndrome types of Chinese medicine (CM) in hyperlipidemia patients of Han, Uyghur, Kazakh nationalities in Xinjiang Uyghur Auton- omous Region. Methods Using cluster random sampling, 1 410 hyperlipidemia patients (18 -70 years old ) were recruited from Urumqi, Turpan, Altay, Ili, Aksu, Hetian in Xinjiang Uyghur Autonomous Re- gion. The general condition, susceptible factors, classification of blood lipids, complications, syndromes of CM, tongue figure, etc. clinical data were investigated using self-formulated Epidemiological Investiga- tion Questionnaire on Susceptible Factors in Different Nationalities of Hyperlipemia Patients in Xinjiang (abbreviated as Questionnaire thereafter). Factor analysis and cluster analysis were performed. Results Cronbach's coefficient for the 54 syndrome items in Questionnaire was 0.891, Kaiser-Meyer-Olkin (KMO) 0. 897, Sig <0.05 in Bartlett's sphericity test. Seventeen common factors were obtained using principal component analysis (PCA). Totally 54 common symptoms of hyperlipidemia were screened, which were then divided into 17 groups with 1 -6 symptoms in each group. F4 (soreness and weakness of waist and knees, sour pain in joints and muscles, body numbness, heavy body sensation, cold limbs), F5 (frequent and clear nocturia, dysuria,-dribble of urine, frequent urination at night), F10 (thirsty, no desire for water, tastelessness, hydroadipsia) , F12 (a white complexion with puffiness, hid- ing fever, hypoactive sexual desire) , and F17 (enuresis) were merged as Shen yang deficiency (SYD) ; F2 (fatigue, drowsiness, depression, spiritlessness, fatigue and disinclination to talk) and F15 (poor ap- petite) were merged as Pi-qi deficiency (PQD) ; F3 (dry mouth and dry pharynx, thirsty, propensity for water, bitter mouth, greasy mouth, stingy mouth, irritability and upset) and F16 (dark red tongue proper, greasy tongue fur) were merged as damp-heat trapped in Pi (DHTP). Results of cluster analysis showed that Pi-Shen deficiency (PSD) was most often seen in hyperlipidemia, and main syndrome types were sequenced from high to low as Pi-Shen deficiency type (46. 2%, 652/1 410) , blockage of cardiac vessels type ( 31. 1% , 438/1 410 ), phlegm and blood stasis internal resistance type ( 13. 3% , 187/1 410), Pi-deficiency induced damp abundance type (8. 3%, 123/1 410), Gan-Shen yin deficiency type (0. 7%, 10/1 410). Conclusions Deficiency syndrome was dominant in hyperlipidemia patients of Xinjiang Uyghur Autonomous Region. Phlegm turbidity, damp heat, and etc. were often complicated. The complex situation was manifested to be involved in multiple organs, qi-blood-fluid mixed disease.


Assuntos
Hiperlipidemias , Medicina Tradicional Chinesa , Adolescente , Adulto , Idoso , China , Humanos , Hiperlipidemias/diagnóstico , Hiperlipidemias/terapia , Pessoa de Meia-Idade , Síndrome , Deficiência da Energia Yang , Deficiência da Energia Yin , Adulto Jovem
20.
J Insect Sci ; 14: 168, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25480968

RESUMO

Eukaryotic initiation factor 4A (eIF-4A) is an essential component for protein translation in eukaryotes. The eIF-4A gene (ApeIF-4A) was isolated and characterized from Antheraea pernyi (Guérin-Méneville) (Lepidoptera: Saturniidae). The obtained cDNA sequence was 1,435-bp long with an open reading frame of 1,266 bp encoding 421 amino acids. The predicted amino acid sequence shared several conserved features as found in known eIF-4As and revealed 74 and 78% identities with eIF-4As of Homo sapiens L. and Drosophila melanogaster (Meigen), respectively. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that ApeIF-4A was transcribed at four developmental stages and in all tissues tested, suggesting that it plays an important role in development of A. pernyi. Homologous alignment suggested that eIF-4As are highly conserved throughout evolution of eukaryote organisms. Phylogenetic trees based on the amino acid and nucleotide sequences of eIF-4A demonstrated a similar topology with the classical systematics, suggesting that it has the potential value in phylogenetic inference of eukaryotes.


Assuntos
Fator de Iniciação 4A em Eucariotos/genética , Proteínas de Insetos/genética , Mariposas/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Fator de Iniciação 4A em Eucariotos/metabolismo , Etiquetas de Sequências Expressas , Feminino , Expressão Gênica , Proteínas de Insetos/metabolismo , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
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