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1.
Nat Commun ; 15(1): 3702, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697969

RESUMO

Hippocampal place cells represent the position of a rodent within an environment. In addition, recent experiments show that the CA1 subfield of a passive observer also represents the position of a conspecific performing a spatial task. However, whether this representation is allocentric, egocentric or mixed is less clear. In this study we investigated the representation of others during free behavior and in a task where female mice learned to follow a conspecific for a reward. We found that most cells represent the position of others relative to self-position (social-vector cells) rather than to the environment, with a prevalence of purely egocentric coding modulated by context and mouse identity. Learning of a pursuit task improved the tuning of social-vector cells, but their number remained invariant. Collectively, our results suggest that the hippocampus flexibly codes the position of others in multiple coordinate systems, albeit favoring the self as a reference point.


Assuntos
Região CA1 Hipocampal , Animais , Feminino , Região CA1 Hipocampal/fisiologia , Região CA1 Hipocampal/citologia , Camundongos , Camundongos Endogâmicos C57BL , Células de Lugar/fisiologia , Recompensa , Comportamento Animal/fisiologia
2.
Phytochem Anal ; 35(2): 321-335, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37816590

RESUMO

INTRODUCTION: Fructus Psoraleae (FP) is a well-known traditional Chinese medicine for the treatment of osteoporosis. However, major quality differences were witnessed owing to its various origins, thus influencing its safety and efficacy. OBJECTIVES: The study aimed to evaluate the quality of FP from different origins and predict its quality evaluation markers. METHODS: Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed for tentative characterisation of the constituents in 10 batches of FP, followed by the utilisation of multivariate statistical analysis methods including principal component analysis and orthogonal partial least squares discriminant analysis for quality evaluation. Network pharmacology approaches were utilised to explore the underlying mechanism of the screened chemotaxonomic markers in treating osteoporosis. RESULTS: Forty-one components in FP including, chalcones, coumarins, coumestans, flavonoids, iso-flavonoids, and phenolics, were characterised based on their fragmentation pathways. Ten batches of FP were basically divided into three categories, and eight chemotaxonomic markers including isopsoralen, calamenene, bakuchiol, psoralen, bavachinin, isoneobavaisoflavone, corylifol C, and neobavaisoflavone were screened. Network pharmacology revealed that the chemotaxonomic markers can act on targets such as AKT1, HSP90AA1, and EGFR and possess effects mainly through glycolysis and wnt/ß-catenin signalling to alleviate osteoporosis. Molecular docking and molecular dynamic simulation confirmed the good binding affinity and stability between proteins and selected markers. So, eight chemotaxonomic markers were all preferentially recommended as quality evaluation markers. CONCLUSION: The study not only provides a reference for the improvement of quality control of FP but also offers a theoretical basis for its further in-depth research in osteoporosis.


Assuntos
Quimiometria , Osteoporose , Simulação de Acoplamento Molecular , Farmacologia em Rede , Flavonoides/farmacologia , Osteoporose/tratamento farmacológico
3.
Lab Chip ; 23(3): 553-559, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36688537

RESUMO

Phagocytic activity is an extremely important indicator that evaluates medicinal effects related to the immune system and functions to investigate the mechanism of how a drug works under conditions such as immunological regulation, immune tolerance, inflammation, cancer, etc. Current techniques based on flow cytometry, fluorescence imaging or numbering CFUs after cell lysis for detecting phagocytosis suffer from long terms of bacteria culturing and complex preparation steps for fluorescent labeling or require a large amount of cell samples to be tested. This study aims at developing a simple and fast method for testing the phagocytic activity of unlabeled and native cells, taking advantage of very high-resolution direct current insulator-based dielectrophoresis (DC-iDEP). The properties of cells are characterized by native whole cell biophysical properties. This strategy not only eliminates the time-consuming bacterial culture work after cell lysis, but also lowers the expenses of bacteria labeling. The introduction of microfluidics reduces the sample volume or reagent needed. The analysis of the biophysical property distributions of native cells and medicine treated cells may lead to a less expensive and rapid tool for evaluating medicinal effects. Furthermore, berberine was investigated for decreasing the phagocytic activity of macrophages and used for comparison of activities. This study works on establishing a label-free, unbiased, and non-destructive method to determine cell phagocytic activity and investigate its use in evaluating medicinal effects on phagocytosis in a single step within a short time.


Assuntos
Microfluídica , Fagócitos , Macrófagos , Fagocitose , Dispositivos Lab-On-A-Chip
4.
Foods ; 11(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36496598

RESUMO

This study investigated the volatile composition and aromatic features of passion fruit wines using a combination of gas chromatography-quadrupole mass spectrometry (GC-qMS), gas chromatography-Orbitrap-mass spectrometry (GC-Orbitrap-MS), electronic nose (E-nose) and sensory evaluation. The results showed that these passion fruit wines possessed different aromatic features confirmed by E-nose. Seventeen sulfur compounds and seventy-eight volatiles were detected in these passion fruit wines using GC-Orbitrap-MS and GC-qMS, respectively. Forty-four volatiles significantly contributed to the overall wine aroma. These wines possessed passion fruit, mango, green apple, lemon and floral aromas confirmed by sensory evaluation. The partial least squares regression analysis indicated that sulfides, esters and terpenes, and terpenes mainly correlated to the passion fruit, mango and green apple aroma, respectively. Sulfur compounds significantly affected the aroma of passion fruit wine. The findings in this study could provide useful insight toward the quality control of passion fruit wine.

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(5): 524-529, 2021 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-34628765

RESUMO

Four-dimensional (4D) printing is an emerging technology that combines science and engineering techniques. The term, "4D printing" was coined in 2013 and since then it has attracted a lot of interests due to its unique ability to have structural or functional transformations over time in response to external stimuli. The most important element of 4D printing is the responsive material. The recent progress research of hydrogels and related new technologies for 4D printing was summarized in the field of implanted medical devices at home and abroad in this paper. Then, it was pointed out the problems of responsive materials for 4D printing. Finally, it was prospected that the development of 4D printing technology in the field of implantable medical devices.


Assuntos
Hidrogéis , Impressão Tridimensional , Próteses e Implantes
6.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(1): 52-56, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33522177

RESUMO

It is well known that chitosan-based composites are widely used in implantable medical devices. The development of chitosan-based composite materials with different types was summarized in this paper, such as inorganic, organic and composite phases. Then, combined with the research focus, the development of 3D printing technology and chitosan-based composites was summarized. It was also pointed out that the existing problems in our research, which need to be solved urgently. At last, the development direction and broad application prospect of chitosan-based composites were prospected. And we look forward to providing reference for relevant research.


Assuntos
Quitosana , Materiais Biocompatíveis , Impressão Tridimensional , Próteses e Implantes
7.
J Nanosci Nanotechnol ; 17(1): 306-12, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29620827

RESUMO

In this work, a simple and effective method for the covalent functionalization of nanodiamond (ND) with four epoxies has been developed. After homogenization by mixed acids and thionyl chlorides, the surface of ND was modified with triethylenetetramine (TETA) to possess amine groups, which were used as active points to react with epoxy by ring opening reaction. Four different epoxies used are bifunctional diglycidyl ether of bisphenol-A (DGEBA), trifunctional triglycidyl p-amino phenol (TGAP), tetrafunctional tetraglycidyldiamino diphenylmethane (TGDDM) and bisphenol-A novolac epoxy resin (BAEPN). FT-IR spectra revealed that the epoxy was covalently attached to the ND (ND-g-epoxy). In addition, functionalized ND particles were characterized with WAXD and UV-Vis spectra to confirm the result. The weight gains as a result of the epoxy-functionalized ND were determined by TGA analysis. The ND-g-epoxy particles were better dispersed in common organic solvents and the average diameters were characterized. The better dispersion and of the modified ND were identified from the SEM images.

8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 40(4): 292-3, 2016.
Artigo em Chinês | MEDLINE | ID: mdl-29775529

RESUMO

Objective: To compare the automatic potentiometry and oxidation-reduction titration methods in determining easily oxidized substances in infusion sets for single use. Methods: The easily oxidized substances in infusion sets for single use were determined using two methods. The precise test and the Student's test were be carried out. Results: Both of the methods could satisfy the analytic demand. The relative standard deviation of automatic potentiometry is 0.06%; the relative standard deviation of oxidation-reduction titration method is 0.07%; when α was 0.05, P value was 0.92. There was no statistically significant difference between the two methods. Conclusion: Automatic potentiometry method can substitute oxidation-reduction titration methods.


Assuntos
Oxirredução , Potenciometria
9.
J Nanosci Nanotechnol ; 15(5): 3780-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26505005

RESUMO

Polyimide/multiwall carbon nanotube (PI/MWCNT) nanocomposite films with homogeneous MWCNTs dispersion were prepared via a solid state shearing pulverization (S3P) approach. Polyimide precursor, viz., poly(amic acid) (PAA), was synthesized from 4,4'-oxydianiline (ODA) and pyromellitic dianhydride (PMDA). Then, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) was mixed with the PAA powder and acid functionalized MWCNTs (acid-MWCNTs) by solid state shearing pulverization (S3P) approach. Finally, PI/MWCNT nanocomposite films were prepared by thermal imidization at elevated temperatures. Using such an approach not only the MWCNTs are well-dispersed but also the mechanical and thermal properties of PI are improved. The tensile strength of PI was enhanced by 74% and the elongation at break decreased to 10.35% with 5.0 wt% acid- MWCNT loading. And the glass transition temperature of PI was increased to 341 degrees C from 303 degrees C because of the strong interfacial bonding between PI and acid-MWCNTs. The solid state shearing pulverization (S3P) approach developed in this study provides a novel method to prepare various polymer composites with desired particle dispersion.


Assuntos
Nanocompostos/química , Nanotubos de Carbono/química , Polímeros/química , Nanotecnologia , Resistência à Tração
10.
J Nanosci Nanotechnol ; 15(8): 5807-15, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369155

RESUMO

Nanodiamonds have recently attracted great attention because of their outstanding hardness in combination with excellent wear resistance. Chemistry modification of the surface and incorporation into a material are required in many applications. In this report, Nanodiamond particles were firstly reduced and two different approaches were used to prepare carbon fiber grafted with nano-diamond. Nanodiamonds functionalized with hydroxyl and amino groups via chemical modification were successfully introduced into the functionalized carbon fiber surface by covalent bonds. The modification of the carbon fibers was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and Wide-angle X-ray diffraction (WAXD). BET surface area of the carbon fibers was increased by about 58% compared with the unmodified fibers.

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