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1.
Chirality ; 36(6): e23682, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38807280

RESUMO

Obtaining optically pure compounds in an eco-friendly and cost-efficient manner plays an important role in human health and pharmaceutical industry. Racemic separation using multistage stereoselective liquid-liquid extraction has become one of the most practical and effective approach to access homochiral enantiomers. Currently, chiral ionic liquids (CILs) with structural designability have become a promising chiral additive and enable them as adjustable candidates for racemic separation. Herein, a high-effective stereoselective liquid-liquid extraction process composed of imidazolium cations and amino acid-derived anions as the chiral additive was established for racemic 2-cyclohexylmandelic acid (CHMA) separation. We have systematically investigated the choice of organic solvent, concentration of CIL, extraction temperature, and the pH of aqueous phase. For three-stage stereoselective extraction, the maximum enantiomeric excess (e.e.) for CHMA was reached up to 40.6%. Furthermore, the mechanism of steric effect and stereoselective capacity between the CILs and racemic CHMA was discussed and simulated. We envision that the work will facilitate the development of CILs in multistage liquid-liquid extraction and promote the large-scale production of optically pure enantiomers.

2.
Sensors (Basel) ; 23(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37177766

RESUMO

Deep learning technology has advanced rapidly and has started to be applied for the detection of welding defects. In the manufacturing process of power batteries for new energy vehicles, welding defects may occur due to the high directivity, convergence, and penetration of the laser beam. The accuracy of deep learning prediction relies heavily on big data, but balanced big data of welding defects is hard to acquire at the battery production site. In this paper, the authors construct a dataset named RIAM, which consists of images captured from an industrial environment for laser welding of power battery modules. RIAM contains four types of images: Normality, Lack of fusion, Surface porosity, and Scaled surface. The characteristics of RIAM are carefully considered in the application scenarios. Moreover, this paper proposes a gradient-based unsupervised model named Grad-MobileNet, which can be trained with only a few normal images and can extract the feature gradients of the input images. Welding defects can then be classified by the gradient distribution. This model is based on MobileNetV3, which is a lightweight convolutional neural network (CNN), and achieves 99% accuracy, which is higher than the accuracy expected from supervised learning.

3.
Anal Bioanal Chem ; 413(30): 7485-7494, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34642782

RESUMO

Excessive use of pesticides in modern agriculture results in large amounts of pesticide residues in agricultural production, greatly threatening human health. Herein, novel two-dimensional leaf-like zeolitic imidazolate framework-L decorated with multi-walled carbon nanotubes (MWCNTs/ZIF-L) was prepared by a facile solvent way and exploited as electrode material for sensitive electrochemical sensing of thiabendazole (TBZ). Two-dimensional ZIF-L presents high surface area, large pore volume, and abundant active sites, which exhibits high enrichment ability towards TBZ molecules, while the MWCNTs interspersed on ZIF-L can prominently enhance the electron transport capability and improve the electrocatalytic activity for TBZ oxidation. Due to the intriguing synergy between the components, the MWCNTs/ZIF-L-based electrochemical sensor reveals a limit of detection (LOD) of 6.0 nmol·L-1, which is lower than that reported in most literatures. Additionally, satisfactory reproducibility and repeatability, long-term stability, and excellent selectivity are acquired. The proposed method was also applied for the detection of TBZ in apple and orange samples with acceptable recoveries.


Assuntos
Técnicas Eletroquímicas/instrumentação , Estruturas Metalorgânicas/química , Nanotubos de Carbono/química , Resíduos de Praguicidas/análise , Tiabendazol/análise , Eletrodos , Limite de Detecção , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Zeolitas/química
4.
J Sep Sci ; 44(22): 4123-4131, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34535951

RESUMO

A stationary phase based on sub-2 µm ground silica monolith particles was fabricated by in situ polymerization and applied in micro-column for separation of peptides. The sub-2 µm silica particles were obtained from monolith using sol-gel process followed by grinding and sedimentation to remove the fines. Initially, the silica monolith particles were pretreated with 3-trimethoxysilyl propyl methacrylate to attach double-bonded ligands onto the surface, then a network structure was formed onto the surface of the particle using styrene, N-isopropylacrylamide, and ethylene glycoldimethacrylate. The effect of the flow rate of the mobile phase on the separation performance was investigated. The stationary phase was characterized by field emission scanning electron microscopy, thermogravimetry, particle size distribution, and element analysis. The resultant phase was packed in glass-lined stainless steel micro-columns (2.1 mm × 50 mm) and evaluated for fast separation. An average number of theoretical plates as high as 9800 plates/column (5.10 µm plate height) was achieved for five synthetic peptides under the optimized flow rate of 0.15 mL/min. The repeatabilities of column-to-column, intraday, and interday through relative standard deviation were found better than 4%, exhibiting satisfactory repeatability of the developed micro-column for fast separation of peptides.


Assuntos
Cromatografia Líquida/métodos , Peptídeos/química , Acrilamidas , Cromatografia Líquida de Alta Pressão/métodos , Análise de Elementos Finitos , Metacrilatos , Microscopia Eletrônica de Varredura , Compostos de Organossilício , Tamanho da Partícula , Polimerização , Dióxido de Silício/química
5.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672038

RESUMO

Our previous study found that desmethylxanthohumol (1) inhibited α-glucosidase in vitro. Recently, further investigations revealed that dehydrocyclodesmethylxanthohumol (2) and its dimer analogue rottlerone (3) exhibited more potent α-glucosidase inhibitory activity than 1. The aim of this study was to synthesize a series of rottlerone analogues and evaluate their α-glucosidase and DPP-4 dual inhibitory activity. The results showed that compounds 4d and 5d irreversibly and potently inhibited α-glucosidase (IC50 = 0.22 and 0.12 µM) and moderately inhibited DPP-4 (IC50 = 23.59 and 26.19 µM), respectively. In addition, compounds 4d and 5d significantly promoted glucose consumption, with the activity of 5d at 0.2 µM being comparable to that of metformin at a concentration of 1 mM.


Assuntos
Inibidores da Dipeptidil Peptidase IV/farmacologia , Flavonoides/síntese química , Flavonoides/farmacologia , Glucose/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Propiofenonas/síntese química , Propiofenonas/farmacologia , Dipeptidil Peptidase 4/metabolismo , Flavonoides/química , Células Hep G2 , Humanos , Cinética , Propiofenonas/química , alfa-Glucosidases/metabolismo
6.
Mikrochim Acta ; 187(11): 623, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33090285

RESUMO

A molecularly imprinted ratiometric fluorescent probe (MIRF probe) was synthesized for the determination of aristolochic acid I (AAI) based on the Schiff-base fluorescent compound N,N'-bis(o-carboxybenzylidene)-p-4,4'-diaminobiphenyl (BDDB). The BDDB was immobilized in the silica nanoparticle (BDDB@SiO2) as an internal standard material. The blue-emitting BDDB@SiO2 and the yellow-emitting carbon quantum dots (y-CDs) were wrapped in the molecularly imprinted polymer (MIP) to provide a reliable reference signal at 440 nm and a fluorescent response signal at 530 nm at the excitation wavelength of 365 nm, respectively. In the preparation of the MIP of the MIRF probe, 4-vinylbenzoic acid as the functional monomer and AAI as the template molecule were used. An imprinting factor of 2.25 was obtained. Under the optimum conditions, the fluorescent response signal at 530 nm was quenched gradually by AAI in the range 1.0 to 120.0 µmol/L, while the reference signal at 440 nm remained unchanged. The limit of detection was 0.45 µmol/L, and the fluorescent color of the MIRF probe changed gradually from yellow to green to blue, which illustrated that the developed probe had a specific AAI recognition ability, a good anti-interference ability, and a sensitively visual determination ability. The probe was successfully applied to the AAI determination in traditional Chinese medicine (TCM) Asarum. The results showed that it had satisfactory recoveries (95.5-107.3%) and low relative standard deviations (2.0%). Furthermore, this method has a potential for the onsite naked eye determination of AAI in TCM samples.Graphical abstract.


Assuntos
Ácidos Aristolóquicos/química , Corantes Fluorescentes/química , Impressão Molecular/métodos , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
7.
BMC Complement Altern Med ; 17(1): 107, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28187732

RESUMO

BACKGROUND: Aristolochiae Fructus (AF) and honey-fried Aristolochiae Fructus (HAF) have been used in China for a long time as anti-tussive and expectorant drugs. Few clinical cases have been reported to be associated with the toxicity of AF and HAF, although relatively high amounts of aristolochic acids (AAs) have been found in them. Our previous experiments have verified from the chemical changes and from traditional toxicology that honey-processing can significantly reduce the toxicity of AF. To further elucidate the detoxification mechanism of honey-processing, comparative pharmacokinetics of AAs in AF and HAF are performed in this study. METHODS: An HPLC-MS/MS (high-performance liquid chromatography-tandem mass spectrometry) method was developed and validated for the determination of AA I, AA II, AA C, AA D and 7-OH AA I in rat plasma. The multi-component pharmacokinetics of AAs in AF and HAF extracts were investigated after the oral administration of three doses to rats. The relative pharmacokinetic parameters were compared systematically. RESULTS: The five AAs shared a similar nonlinear PK (pharmacokinetic) process. They involve rapid absorption and elimination, and they were fit into a two-compartmental open model. Some significant pharmacokinetic differences were observed between the AF and HAF groups: the C max and AUC values of AA I and AA II in the AF groups were much higher than those of the HAF groups. CONCLUSIONS: Honey-frying technology can reduce the toxicity of AF by significantly decreasing the absorption of AA I and AA II. The PK parameters obtained in this work could provide valuable references for the toxicity research and clinical use of Aristolochiaceae herbs, including AF and HAF. Process diagram of comparative pharmacokinetics study.


Assuntos
Aristolochia/química , Ácidos Aristolóquicos/farmacocinética , Frutas/química , Mel , Extratos Vegetais/farmacocinética , Administração Oral , Animais , Ácidos Aristolóquicos/sangue , Ácidos Aristolóquicos/química , Limite de Detecção , Modelos Lineares , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
8.
Analyst ; 138(20): 5904-12, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23928725

RESUMO

A novel sorbent for magnetic solid-phase extraction, 1,4,7,10-tetrabenzyl-1,4,7,10-tetraazacyclododecane (TBCD) modified magnetic nanoparticles, was synthesized in this work. The four benzyl groups of TBCD provide the Fe3O4-TBCD nanoparticles with strong adsorption capacity for polycyclic aromatic hydrocarbons (PAHs) due to their π-π stacking interaction, which increases selectivity of the synthesized material to target analytes. The prepared material was characterized by scanning electron microscopy, X-ray diffraction patterns, Fourier transform infrared spectroscopy and vibrating sample magnetometry. The results indicated that the Fe3O4-TBCD nanoparticles were successfully prepared, and the particles were homogeneous nanospheres with excellent magnetic properties. Based on the optimized extraction conditions, a rapid and effective method was developed for the pre-concentration of PAHs from environmental water samples by combination with high performance liquid chromatography (HPLC). Satisfactory precision and accuracy of the developed method were obtained in a low concentration range of 0.3 ng L(-1) to 1.2 × 10(3) ng L(-1). This method produced lower limits of detection in the range of 3.0 × 10(-2) ng L(-1) to 1.2 ng L(-1). The high pre-concentration rate and efficiency of the method ensure its successful application in extraction of trace PAHs from large volumes of environmental water samples. The extraction recoveries in environmental water samples ranged from 81.1% to 115.5% with the relative standard deviations (n = 5) less than 10%.

9.
Analyst ; 138(2): 569-75, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23172420

RESUMO

An octadecyl-functionalized solid-phase microextraction (SPME) fiber was prepared by sol-gel technology with an anodized Ti wire as the substrate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (C(18)-TMS) and tetraethoxysilane (TEOS) as sol-gel precursors. The anodized Ti wire has high mechanical strength and has numerous titanol groups on its surface for sol-gel reactions, consequently offering better performances than the commercial fragile fused silica substrate. The C(18)-TMS/TEOS sol-gel coated fiber has good thermal stability and stability against organic solvents. There is no loss in the performance after 100 cycles of exposure to acetonitrile and high temperature (300 °C) in turn. The developed fiber with a very thin (ca. 2 µm) coating thickness exhibits comparable or even superior extraction capability relative to the commercial 100 µm polydimethylsiloxane (PDMS) fiber. Under optimized conditions, the detection limits for the polycyclic aromatic hydrocarbons are in the range of 0.003 to 0.025 µg L(-1) with a linear range from 0.01 to 20 µg L(-1). The proposed method was successfully applied in the analysis of environmental water samples with the recoveries ranging from 85.3 to 101.8%.

10.
Analyst ; 138(19): 5726-33, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23900298

RESUMO

In this paper, tris(2,3-dibromopropyl) isocyanurate (TBC) is for the first time as far as we know determined by ultrasensitive photoelectrochemical (PEC) immunoassay using an antibody-modified ternary hybrid CdTe/Au-TiO2 nanotube arrays (NTAs) photoelectrode, developed by the pulse electrodeposition technique. The as-prepared hybrid shows enhanced photon absorption and photocurrent response, which subsequently increased the photoelectrical conversion efficiency in the visible region. TBC-antibody (Ab) was developed in rabbits as a result of immunization with the BSA-TBC conjugate and covalently cross-linked onto the CdTe/Au-TiO2 NTAs. Since the photocurrent is highly dependent on the TiO2 surface properties, the specific interaction between TBC and the antibody results in a sensitive change in the photocurrent, which displayed a linear range of 5.0 × 10(-11) to 5.0 × 10(-5) M and a low detection limit of 5.0 × 10(-11) M for TBC determination. This proposed strategy highlights the application of TiO2 nanotube in visible-light-activated photoelectrochemical biosensing, which could largely reduce the destructive effect of UV light on biomolecules.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Nanotubos/química , Processos Fotoquímicos , Animais , Compostos de Cádmio/química , Ligas Dentárias/química , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio/métodos , Organofosfatos/química , Coelhos , Telúrio/química , Triazinas/química
11.
J Sep Sci ; 36(7): 1283-90, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23471877

RESUMO

Metal-organic frameworks, a new class of materials with high surface area and great porosity, have been widely applied in gas sorption. It is generally known that metal-organic framework 5 cannot be applied in aqueous phase since it is water sensitive. However, this work reveals that the derived material of metal-organic framework 5 is a good SPE sorbent that can be applied to aqueous phases. Metal-organic framework 5 was prepared and used as a SPE sorbent for the determination of polycyclic aromatic hydrocarbons in environmental matrices coupling with HPLC. The water treatment induced changes in the properties were investigated in detail. Even though metal-organic framework 5 is conversed to a second phase after water treatment, it still shows high extraction ability. Under the optimized experimental conditions, good sensitivity levels were achieved with low LODs ranging from 0.4 to 4.0 ng L(-1) and a linearity of 0.004-20 µg L(-1) (R(2) > 0.996) for the investigated polycyclic aromatic hydrocarbons. The method has been validated in the analysis of real water samples with recoveries in the range of 80.2-120.2% and RSDs in the range of 0.5-11.7%.


Assuntos
Monitoramento Ambiental/métodos , Compostos Organometálicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Microscopia Eletrônica de Varredura , Nanopartículas/análise , Porosidade , Água/química
12.
Zhong Yao Cai ; 36(4): 538-41, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-24133995

RESUMO

OBJECTIVE: To evaluate the degree of de-toxification of Aristolochiae Fructus by honey-toasting technology from chemical viewpoint. METHODS: The contents of aristolochic acid analogues (AAs) in Aristolochiae Fructus and its honey-toasted product were determined by HPLC, and the degree of de-toxification was evaluated comprehensively. RESULTS: After honey-toasted, the contents of AAs decreased to varying degrees, and some new compounds were found. CONCLUSION: The constituents and contents of Aristolochiae Fructus change after honey-toasted, which indicate honey-toasting can reduce the toxicity of Aristolochiae Fructus.


Assuntos
Aristolochia/química , Ácidos Aristolóquicos/química , Medicamentos de Ervas Chinesas/química , Frutas/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Mel , Reprodutibilidade dos Testes , Tecnologia Farmacêutica
13.
J Chromatogr A ; 1694: 463904, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36870253

RESUMO

Graphene-functionalized nickel foam (NF) sorbent materials were prepared and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Thermogravimetric analysis. For the separation and detection of polycyclic aromatic hydrocarbons (PAHs) in five Chinese medicine samples, namely dandelion, fructus aurantii, peppermint, mulberry leaf and embryo chrysanthemum, a method combining dispersive micro-solid phase extraction and gas chromatography-mass spectrometry (GC-MS) was developed. Four conditions affecting the extraction efficiency, such as the type of desorption solvent, the amount of sorbent, the extraction time and the volume of water sample, were optimized. The results of the methodological validation showed that NF@SiO2@G was able to adsorb PAHs well and with good reproducibility. All analytes showed good linearity in the concentration range of 20-2000 ng/mL with coefficient of determination R2≥0.9956. The limit of detection was 0.98-13.34 ng/mL, and the limit of quantification ranged from 3.25 to 44.47 ng/mL. Both the intra-day and inter-day precision were lower than 15.46%, and the spiked recoveries were in the range of 75.5-118.4%. The total contents of the 16 PAHs contained in these five Chinese herbal medicines (CHMs) were varied from 450 to 1557 µg/kg. The results indicated that the graphene-functionalized NF sorbent combined with GC-MS can effectively detect PAHs in CHMs.


Assuntos
Grafite , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Níquel/análise , Grafite/química , Dióxido de Silício/química , Reprodutibilidade dos Testes , Limite de Detecção , Extração em Fase Sólida/métodos , Extratos Vegetais , Poluentes Químicos da Água/análise
14.
Talanta ; 265: 124916, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37442001

RESUMO

Covalent organic framework coated nickel foam (NF@COF) was prepared as a sorbent for the dispersive solid phase extraction (DSPE) of polycyclic aromatic hydrocarbons (PAHs) from Chinese herbal medicines (CHMs) prior to their determination by gas chromatography-mass spectrometry (GC-MS). The structure and morphology of the as-synthesized NF@COF were characterized by different techniques. Various key parameters affecting the performance of the DSPE method, including the amount of sorbent, desorption solvent, desorption volume and time, extraction time, and sample volume, were investigated. Under the optimized conditions, NF@COF combined with GC-MS was successfully applied to the determination of 16 PAHs in CHMs. The method showed wide linearity (20-2000 ng mL-1), low limits of determination (0.3-2.7 ng mL-1), and high recoveries (78.0-124%). These results revealed that NF@COF has the potential for efficient extraction of PAHs from complex samples.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Níquel/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Limite de Detecção , Extração em Fase Sólida/métodos , Extratos Vegetais , Poluentes Químicos da Água/análise
15.
Med Image Anal ; 83: 102650, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334394

RESUMO

Dual-energy cone-beam computed tomography (DE-CBCT) is a promising imaging technique with foreseeable clinical applications. DE-CBCT images acquired with two different spectra can provide material-specific information. Meanwhile, the anatomical consistency and energy-domain correlation result in significant information redundancy, which could be exploited to improve image quality. In this context, this paper develops the Transformer-Integrated Multi-Encoder Network (TIME-Net) for DE-CBCT to remove the limited-angle artifacts. TIME-Net comprises three encoders (image encoder, prior encoder, and transformer encoder), two decoders (low- and high-energy decoders), and one feature fusion module. Three encoders extract various features for image restoration. The feature fusion module compresses these features into more compact shared features and feeds them to the decoders. Two decoders perform differential learning for DE-CBCT images. By design, TIME-Net could obtain high-quality DE-CBCT images using two complementary quarter-scans, holding great potential to reduce radiation dose and shorten the acquisition time. Qualitative and quantitative analyses based on simulated data and real rat data have demonstrated the promising performance of TIME-Net in artifact removal, subtle structure restoration, and reconstruction accuracy preservation. Two clinical applications, virtual non-contrast (VNC) imaging and iodine quantification, have proved the potential utility of the DE-CBCT images provided by TIME-Net.


Assuntos
Animais , Ratos
16.
Sci Rep ; 13(1): 6640, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095263

RESUMO

In this paper, a novel composite is constructed as a non-enzymatic hydrogen peroxide (H2O2) sensor by liquid-phase exfoliation method, which is composed of copper oxide, cuprous oxide and silver nanoparticles doped few-layer-graphene (CuxO/Ag@FLG). Its surface morphology and composition were characterized by scanning electron microscopy (SEM) and X-ray photo spectroscopy (XPS), and its H2O2 sensing performances include catalytic reduction and quantitative detection were studied with electrochemical methods. Our sensor had a high sensitivity of 174.5 µA mM-1 cm-2 (R2 = 0.9978) in an extremely wide range of concentrations from 10 µM to 100 mM, a fast response (about 5 s) and a low limit of detection (S/N = 3) of 2.13 µM. The sensor exhibits outstanding selectivity in the presence of various biological interference, such as dopamine, ascorbic acid, uric acid, citric acid, etc. In addition, the constructed sensor continued 95% current responsiveness after 1 month of storage further points to its long-term stability. Last but not least, it has a good recovery rate (90.12-102.00%) in milk sold on the open market, indicating that it has broad application possibilities in the food industry and biological medicine.


Assuntos
Grafite , Nanopartículas Metálicas , Animais , Grafite/química , Nanopartículas Metálicas/química , Peróxido de Hidrogênio/análise , Leite/química , Prata/química , Técnicas Eletroquímicas/métodos
17.
PLoS One ; 18(5): e0270614, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37141336

RESUMO

The purpose of this study was to determine whether FABP1 and FAS regulate expression of collagen and its crosslinking via lysyl oxidase in isolated adipocytes from Zongdihua pigs. We aimed to identify biochemical processes affecting meat quality using molecular tools to provide a basis for breeding improvement of these animals. We measured expression levels of FABP1 and related genes using qRT-PCR in longissimus dorsi muscle and subcutaneous adipose tissues. Primary adipocytes from fat tissues were isolated and FABP1 and FAS were over-expressed from recombinant plasmids. Sequence analysis of the cloned genes indicated that FABP1 encodes a hydrophobic protein of 128 amino acids and contained 12 predicted phosphorylation sites and no transmembrane regions. The basal levels of FABP1 and FAS expression in pig tissues were 3-3.5-fold higher in subcutaneous fat compared with muscle (P < 0.01). Recombinant expression plasmids were successfully transfected into the cloned preadipocytes and (a) over-expression of FAS resulted in significantly increased expression of COL3A1 (P < 0.05) and significantly inhibited lysyl oxidase LOX expression (P < 0.01); (b) over-expression of FABP1 significantly increased COL3A1 expression (P < 0.01) and significantly inhibited LOX expression (P< 0.05) and significantly reduced lysyl oxidase activity (P < 0.01). Therefore, FAS enhanced FABP1 expression resulting in increased collagen accumulation and this preliminarily suggested that FAS and FABP1 can serve as fat-related candidate genes and provide a theoretical basis for the study of fat deposition in Zongdihua pigs.


Assuntos
Ácidos Graxos , Proteína-Lisina 6-Oxidase , Suínos , Animais , Ácidos Graxos/metabolismo , Proteína-Lisina 6-Oxidase/genética , Adipócitos/metabolismo , Colágeno/metabolismo , Proteínas de Ligação a Ácido Graxo/genética , Ácido Graxo Sintases/metabolismo
18.
Eur J Med Chem ; 261: 115822, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37793325

RESUMO

In order to overcome the current LNP-mRNA delivery system's weakness of poor stability and rapid degradation by nuclease, a novel chol-CGYKK molecule and then the new phospholipid liposome were designed and prepared. A solid phase approach synthesized CGYKK and connected it to cholesterol via a disulfide linker to form the desired chol-CGYKK. Four formulated samples with different proportions of excipients were prepared by freeze-drying cationic liposomes and packaged S-mRNA. The stability test shows that after six months at 4 °C, the encapsulation rate of this novel phospholipid liposome was still approximately 90%, which would significantly improve the storage and transportation requirement. Transmission electron microscopy, atomic force microscopy, and scanning electron microscopy indicated that the liposomes were spherical and uniformly dispersed. On comparing the levels of mRNA protein expression of the four formulated samples, the S protein vaccine expression of formulated sample 1 was the highest. Uptake by vector cells for formulated sample 1 showed that compared to Lipo2000, and the transfection efficiency was 66.7%. Furthermore, the safety evaluation of the CGYKK and mRNA vaccine liposomes revealed no toxic effects. The in vivo study demonstrated that this novel mRNA vaccine had an immune response. However, it was still not as good as the LNP group right now, but its excellent physicochemical properties, stability, in vitro biological activity, and in vivo efficacy against SARS-CoV-2 provided new strategies for developing the next generation of mRNA delivery system.


Assuntos
Peptídeos Penetradores de Células , Lipossomos , Lipossomos/química , Esteróis , Transfecção , Fosfolipídeos
19.
Food Funct ; 14(22): 9974-9998, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37916682

RESUMO

Lycopene is an important pigment with an alkene skeleton from Lycopersicon esculentum, which is also obtained from some red fruits and vegetables. Lycopene is used in the food field with rich functions and serves in the medical field with multiple clinical values because it has dual functions of both medicine and food. It was found that lycopene was mainly isolated by solvent extraction, ultrasonic-assisted extraction, supercritical fluid extraction, high-intensity pulsed electric field-assisted extraction, enzymatic-assisted extraction, and microwave-assisted extraction. Meanwhile, it was also obtained via 2 synthetic pathways: chemical synthesis and biosynthesis. Pharmacological studies revealed that lycopene has anti-oxidant, hypolipidemic, anti-cancer, immunity-enhancing, hepatoprotective, hypoglycemic, cardiovascular-protective, anti-inflammatory, neuroprotective, and osteoporosis-inhibiting effects. The application of lycopene mainly includes food processing, animal breeding, and medical cosmetology fields. It is hoped that this review will provide some useful information and guidance for future study and exploitation of lycopene.


Assuntos
Carotenoides , Solanum lycopersicum , Licopeno/farmacologia , Licopeno/análise , Carotenoides/química , Antioxidantes/farmacologia , Antioxidantes/análise , Frutas/química
20.
NPJ Vaccines ; 8(1): 153, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37813912

RESUMO

Some studies have shown that lyophilization significantly improves the stability of mRNA-LNPs and enables long-term storage at 2-8 °C. However, there is little research on the lyophilization process of mRNA-lipid nanoparticles (LNPs). Most previous studies have used empirical lyophilization with only a single lyoprotectant, resulting in low lyophilization efficiency, often requiring 40-100 h. In the present study, an efficient lyophilization method suitable for mRNA-LNPs was designed and optimized, shortening the total length of the lyophilization process to 8-18 h, which significantly reduced energy consumption and production costs. When the mixed lyoprotectant composed of sucrose, trehalose, and mannitol was added to mRNA-LNPs, the eutectic point and collapse temperature of the system were increased. The lyophilized product had a ginger root-shaped rigid structure with large porosity, which tolerated rapid temperature increases and efficiently removed water. In addition, the lyophilized mRNA-LNPs rapidly rehydrated and had good particle size distribution, encapsulation rate, and mRNA integrity. The lyophilized mRNA-LNPs were stable at 2-8 °C, and they did not reduce immunogenicity in vivo or in vitro. Molecular dynamics simulation was used to compare the phospholipid molecular layer with the lyoprotectant in aqueous and anhydrous environments to elucidate the mechanism of lyophilization to improve the stability of mRNA-LNPs. This efficient lyophilization platform significantly improves the accessibility of mRNA-LNPs.

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