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1.
Luminescence ; 39(5): e4769, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720528

RESUMEN

Fluorene nucleus derivatives show great potential for building outstanding fluorescence probes. In this paper, a novel fluorescent probe was developed by reacting with fluorene core with azacyclobutane, which exhibits typical solvation chromogenic effect in solvent. The fluorescence of the probe quenched in highly polar solvent. Based on this phenomenon, a novel fluorescence system for trace water was constructed. The response of this probe was fast (30 s) and sensitive for the detection of trace water in organic solvents, and the detection limit of water content in DMSO reached 0.13%. In addition, the probe can also be made as a test strip combined with homemade portable device and a smartphone for rapid detection of trace water. The luminescence mechanism of the probe is theoretically calculated based on time-contained density functional theory (TDDFT). To showcase its practicality, it has been applied for the detection of trace water in honey and alcohol by dipstick. This method provides a new idea for designing efficient fluorescent probes based on dipstick and mobile phone rapid detection.


Asunto(s)
Fluorenos , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Agua , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Fluorenos/química , Agua/química , Estructura Molecular , Límite de Detección , Teoría Funcional de la Densidad , Fluorescencia , Contaminantes Químicos del Agua/análisis
2.
ACS Omega ; 8(39): 36302-36310, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37810707

RESUMEN

Cannabis is the most prevalent abused substance after alcohol, and its consumption severely harms human health and thus adversely impacts society. The identification and quantification of cannabis in urine play important roles in practical forensics. Excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor (PARAFAC) analysis was developed to identify and quantify the four main ingredients of cannabis in urine samples. The main ingredients of cannabis including Δ-9-tetrahydrocannabinol (THC), cannabidiol, cannabinol, and tetrahydrocannabinolic acid (THC-COOH) exhibited diverse fluorescence characteristics, and the concentrations of these compounds depicted a positive linear relationship with the fluorescence intensity at the ng/mL level. The EEM/PARAFAC method adequately characterized and discriminated the four ingredients in calibration and prediction samples with a low root-mean-square error of prediction (RMSEP; 0.03-0.07 µg/mL) and limit of quantitation (LOQ; 0.26-0.71 µg/mL). The prediction results of the EEM/PARAFAC method well correlated with that of GC-MS with a low RMSEP range (0.01-0.05 µg/mL) and LOQ range (0.07-0.44 µg/mL) in urine samples. The EEM spectroscopic investigation coupled with the PARAFAC algorithm results in an organic, solvent-less, fast, reliable tool to perform accurate and rapid screening of cannabis abusers.

3.
Sci Rep ; 13(1): 14526, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37666953

RESUMEN

Herein, a novel Ag NP substrate doped with Au nanobipyramids was designed and fabricated via a convenient procedure of galvanic reaction for the identification and classification of amphetamine-type stimulants (ATS) in oral fluids in combination with surface enhanced Raman scattering (SERS). The substrate was shown to have a three-dimensional nanostructure, high SERS activity, and good stability. In combination with SERS, the Ag NP substrate doped with Au nanobipyramids was able to detect ultra-low traces of ATS, including amphetamine, methylamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), and 3,4-methylenedioxymethylamphetamine (MDMA) in oral fluid with limit of detection (LOD) and limit of determination quantitation (LOQ) as low as 10-9 mg/mL, which is much better than the current spectroscopic techniques. The equations between concentration and peaks intensity for quantitative analysis displied good doublelogarithmic linear relations and reliability figures of merit at nanogram concentration level in compartion with GC-MS method. The approach can be broadly applied to the ultra-low trace detection of ATS in oral fluid and would be particularly useful for the analyses of nitrogenous organic compounds.


Asunto(s)
3,4-Metilenodioxianfetamina , Estimulantes del Sistema Nervioso Central , Metanfetamina , Anfetamina , Reproducibilidad de los Resultados , Compuestos de Nitrógeno
4.
ACS Omega ; 7(2): 1712-1721, 2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35071866

RESUMEN

Recently, the application of novel nanomaterials, especially magnetic nanomaterials in the development of latent fingerprints (LFP), has become the hot focus for forensic scientists and criminal investigators. As a type of recyclable, environment-friendly material, Fe3O4 nanoparticles achieve a wonderful effect in visualization of LFP. We first report the synthesis and encapsulation of nano-Fe3O4 through "facile coprecipitation", (3-mercaptopropyl)triethoxysilane was covalently embedded into Fe3O4 nanoparticles, and the Fe3O4 core was encapsulated by the nanosilver to prepare novel magnetic nanomaterials (P-MNP@Ag) with the core-shell configuration. For comparison, the magnetic nanomaterials (S-MNP@Ag) were prepared by surface modification. Their composition, structure, and properties were characterized by SEM, TEM, XRD, IR, XPS, and VSM. Compared with commercially available gold powder, silver powder, bare magnetic powder, and prepared S-MNP@Ag, the development effect of LFP on different objects by using P-MNP@Ag had better performance, which presented the advantages of low background interference, high sensitivity, and clear secondary details in LFP. In the crime scenes of some influential cases, P-MNP@Ag had been applied to the visualization of LFP. The biometric identification of criminal suspects was confirmed through fingerprint comparison, which was highly affirmed by the public security department.

5.
Int J Oncol ; 59(4)2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34515325

RESUMEN

Glioblastoma multiforme (GBM) is the most prevalent and aggressive type of adult gliomas. Despite intensive therapy including surgery, radiation, and chemotherapy, invariable tumor recurrence occurs, which suggests that glioblastoma stem cells (GSCs) render these tumors persistent. Recently, the induction of GSC differentiation has emerged as an alternative method to treat GBM, and most of the current studies aim to convert GSCs to neurons by a combination of transcriptional factors. As the tumor microenvironment is typically acidic due to increased glycolysis and consequently leads to an increased production of lactic acid in tumor cells, in the present study, the role of acid­sensing ion channel 1a (ASIC1a), an acid sensor, was explored as a tumor suppressor in gliomagenesis and stemness. The bioinformatics data from The Cancer Genome Atlas revealed that ASIC1 expression levels in GBM tumor tissues were lower than those in normal brain, and glioma patients with high ASIC1 expression had longer survival than those with low ASIC1 expression. Our immunohistochemistry data from tissue microarray revealed that ASIC1a expression was negatively associated with glioma grading. Functional studies revealed that the downregulation of ASIC1a promoted glioma cell proliferation and invasion, while upregulation of ASIC1a inhibited their proliferation and invasion. Furthermore, ASIC1a suppressed growth and proliferation of glioma cells through G1/S arrest and apoptosis induction. Mechanistically, ASIC1a negatively modulated glioma stemness via inhibition of the Notch signaling pathway and GSC markers CD133 and aldehyde dehydrogenase 1. ASIC1a is a tumor suppressor in gliomagenesis and stemness and may serve as a promising prognostic biomarker and target for GBM patients.


Asunto(s)
Canales Iónicos Sensibles al Ácido/fisiología , Neoplasias Encefálicas/patología , Glioblastoma/patología , Células Madre Neoplásicas/fisiología , Antígeno AC133/análisis , Canales Iónicos Sensibles al Ácido/análisis , Familia de Aldehído Deshidrogenasa 1/análisis , Apoptosis , Neoplasias Encefálicas/mortalidad , Línea Celular Tumoral , Proliferación Celular , Glioblastoma/mortalidad , Humanos , Invasividad Neoplásica , Microambiente Tumoral
6.
Front Pharmacol ; 11: 590723, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33381038

RESUMEN

We have reported that transient receptor potential melastatin-related 7 (TRPM7) regulates glioma stem cells (GSC) growth and proliferation through Notch, STAT3-ALDH1, and CD133 signaling pathways. In this study, we determined the major contributor(s) to TRPM7 mediated glioma stemness by further deciphering each individual Notch signaling. We first determined whether TRPM7 is an oncotarget in glioblastoma multiforme (GBM) using the Oncomine database. Next, we determined whether TRPM7 silencing by siRNA TRPM7 (siTRPM7) induces cell growth arrest or apoptosis to reduce glioma cell proliferation using cell cycle analysis and annexin V staining assay. We then examined the correlations between the expression of TRPM7 and Notch signaling activity as well as the expression of GSC markers CD133 and ALDH1 in GBM by downregulating TRPM7 through siTRPM7 or upregulating TRPM7 through overexpression of human TRPM7 (M7-wt). To distinguish the different function of channel and kinase domain of TRPM7, we further determined how the α-kinase-dead mutants of TRPM7 (α-kinase domain deleted/M7-DK and K1648R point mutation/M7-KR) affect Notch activities and CD133 and ALDH1 expression. Lastly, we determined the changes in TRPM7-mediated regulation of glioma cell growth/proliferation, cell cycle, and apoptosis by targeting Notch1. The Oncomine data revealed a significant increase in TRPM7 mRNA expression in anaplastic astrocytoma, diffuse astrocytoma, and GBM patients compared to that in normal brain tissues. TRPM7 silencing reduced glioma cell growth by inhibiting cell entry into S and G2/M phases and promoting cell apoptosis. TRPM7 expression in GBM cells was found to be positively correlated with Notch1 signaling activity and CD133 and ALDH1 expression; briefly, downregulation of TRPM7 by siTRPM7 decreased Notch1 signaling whereas upregulation of TRPM7 increased Notch1 signaling. Interestingly, kinase-inactive mutants (M7-DK and M7-KR) resulted in reduced activation of Notch1 signaling and decreased expression of CD133 and ALDH1 compared to that of wtTRPM7. Finally, targeting Notch1 effectively suppressed TRPM7-induced growth and proliferation of glioma cells through cell G1/S arrest and apoptotic induction. TRPM7 is responsible for sustained Notch1 signaling activation, enhanced expression of GSC markers CD133 and ALDH1, and regulation of glioma stemness, which contributes to malignant glioma cell growth and invasion.

7.
Front Oncol ; 9: 1413, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31921670

RESUMEN

Objectives: Our previous findings demonstrate that channel-kinase transient receptor potential (TRP) ion channel subfamily M, member 7 (TRPM7) is critical in regulating human glioma cell migration and invasion. Since microRNAs (miRNAs) participate in complex regulatory networks that may affect almost every cellular and molecular process during glioma formation and progression, we explored the role of miRNAs in human glioma progression by comparing miRNA expression profiles due to differentially expressed TRPM7. Methods: First, we performed miRNA microarray analysis to determine TRPM7's miRNA targets upon TRPM7 silencing in A172 cells and validated the miRNA microarray data using A172, U87MG, U373MG, and SNB19 cell lines by stem-loop RT-qPCRs. We next determined whether TRPM7 regulates glioma cell proliferation and migration/invasion through different functional domains by overexpressing wild-type human TRPM7 (wtTRPM7), two mutants with TRPM7's α-kinase domain deleted (Δkinase-DK), or a point mutation in the ATP binding site of the α-kinase domain (K1648R-KR). In addition, we determined the roles of miR-28-5p in glioma cell proliferation and invasion by overexpressing or under expressing miR-28-5p in vitro. Lastly, we determined whether a Ras-related small GTP-binding protein (Rap1b) is a target of miR-28-5p in glioma tumorigenesis. Results: The miRNA microarray data revealed a list of 16 downregulated and 10 upregulated miRNAs whose transcripts are significantly changed by TRPM7 knock-down. Cell invasion was significantly reduced in two TRPM7 mutants with inactive kinase domain, Δkinase, and K1648R transfected glioma cells. miR-28-5p overexpression suppressed glioma cells' proliferation and invasion, and miR-28-5p under expression led to a significant increase in glioma cell proliferation and migration/invasion compared to that of the controls. miR-28-5p suppressed glioma cell proliferation and migration by targeting Rap1b. Co-transfection of siRap1b with miR28-5p inhibitor reduced the glioma cell proliferation and invasion, caused by the latter. Conclusions: These results indicate that TRPM7's channel activity is required for glioma cell growth while the kinase domain is required for cell migration/invasion. TRPM7 regulates miR-28-5p expression, which suppresses cell proliferation and invasion in glioma cells by targeting Rap1b signaling.

8.
Food Res Int ; 108: 237-245, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29735053

RESUMEN

Emotional reactions towards products play an essential role in consumers' decision making, and are more important than rational evaluation of sensory attributes. It is crucial to understand consumers' emotion, and the relationship between sensory properties, human liking and choice. There are many inconsistencies between Asian and Western consumers in the usage of hedonic scale, as well as the intensity of facial reactions, due to different culture and consuming habits. However, very few studies discussed the facial responses characteristics of Asian consumers during food consumption. In this paper, explicit liking measurement (hedonic scale) and implicit emotional measurement (facial expressions) were evaluated to judge the consumers' emotions elicited by five types of juices. The contributions of this study included: (1) Constructed the relationship model between hedonic liking and facial expressions analyzed by face reading technology. Negative emotions "sadness", "anger", and "disgust" showed noticeable high negative correlation tendency to hedonic scores. The "liking" hedonic scores could be characterized by positive emotion "happiness". (2) Several emotional intensity based parameters, especially dynamic parameter, were extracted to describe the facial characteristic in sensory evaluation procedure. Both amplitude information and frequency information were involved in the dynamic parameters to remain more information of the emotional responses signals. From the comparison of four types of emotional descriptive parameters, the maximum parameter and dynamic parameter were suggested to be utilized for representing emotional state and intensities.


Asunto(s)
Pueblo Asiatico/psicología , Comportamiento del Consumidor , Emociones , Expresión Facial , Preferencias Alimentarias , Jugos de Frutas y Vegetales , Filosofía , Adolescente , Adulto , China , Conducta de Elección , Femenino , Preferencias Alimentarias/etnología , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Factores de Tiempo , Grabación en Video , Adulto Joven
9.
Org Biomol Chem ; 12(41): 8336-45, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25216100

RESUMEN

A new class of 9-amino-(9-deoxy)cinchona alkaloid-derived chiral phase-transfer catalysts bearing amino groups was developed by using known cinchona alkaloids as the starting materials. Due to the transformation of the 9-hydroxyl group into a 9-amino functional group, the catalytic performances were significantly improved in comparison with the corresponding first generation phase-transfer catalysts, and excellent yields (92-99%) and high enantioselectivities (87-96% ee) were achieved in the benchmark asymmetric α-alkylation of glycine Schiff base. Based on the special contribution of the amino group to the high yield and enantioselectivity, the possible catalytic mechanism was conjectured.


Asunto(s)
Alcaloides de Cinchona/química , Alcaloides Indólicos/química , Quinuclidinas/química , Catálisis , Alcaloides de Cinchona/síntesis química , Alcaloides Indólicos/síntesis química , Estructura Molecular , Transición de Fase , Quinuclidinas/síntesis química , Estereoisomerismo
10.
Dalton Trans ; 42(18): 6513-22, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23474609

RESUMEN

A novel type of phosphonate-containing polystyrene copolymers 1a-e bearing an N'-alkylated TsDPEN chiral ligand and double-stranded polystyrene chains were prepared for the first time using simple radical copolymerization of 1-phosphonate styrene with (R,R)-N'-4'-vinylbenzyl-N-4-vinylbenzenesulfonyl-1,2-diphenylethylene-1,2-diamine. Through the coprecipitation of their supported Ru polystyrene copolymers 2a-e and NaH2PO4 with ZrOCl2, pillared hybrid zirconium phosphate-phosphonate-anchored Ru catalysts 3a-e and 4d1-d5 were obtained as heterogeneous catalysts suitable for aqueous asymmetric transfer hydrogenation. In the aqueous asymmetric transfer hydrogenation of aromatic ketones, the anchored Ru catalysts showed good catalytic activities, chemoselectivities (~100%), and enantioselectivities (73.6% ee to 95.6% ee). The Ru catalysts retained their catalytic properties even at the fifth recycle time (92.2% conv., 92.1% ee). However, corresponding supported Ru catalyst 3d' resulted in disappointing reusability because of the loss of ruthenium in every recycle process. The conversions of aromatic ketones were closely related to the o-, m- or p-positions of the substituents on the aromatic ring caused by shape-selective matching.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Organometálicos/química , Organofosfonatos/química , Poliestirenos/química , Rutenio/química , Agua/química , Circonio/química , Catálisis , Hidrogenación , Modelos Moleculares , Conformación Molecular , Estereoisomerismo , Propiedades de Superficie
11.
Dalton Trans ; 41(18): 5715-26, 2012 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-22451074

RESUMEN

A series of novel porous zirconium phosphonate-supported 9-amino-9-deoxy-epi-cinchonidines of general formulae Zr(OH)(4-2x)(O(3)PR)(x)·nH(2)O and Zr(HPO(4))(2-x)(O(3)PR)(x)·nH(2)O with the different arm chain lengths (n = 2-6) and mean diameters of approximately 20-40 nm have been prepared as heterogeneous organocatalysts. The different microtextures of zirconium phosphonates were also obtained by using template guest molecules, such as Et(3)N, NaH(2)PO(4) and sodium dodecyl benzene sulfonate. In the heterogeneous asymmetric aldol addition of p-nitrobenzaldehyde to cyclohexanone, excellent catalytic properties were achieved, especially in an aqueous medium. After completing the reaction, those zirconium phosphonate-supported 9-amino-9-deoxy-epi-cinchonidine organocatalysts could be readily recovered in quantitative yield by centrifugation or filtration, and reused for five consecutive runs without significant loss in catalytic performance. In particular, due to the steric confinement effect of the inorganic backbone, the single different configuration among possible four stereo-isomers in aldol adducts were favorably obtained, respectively depending on the interaction between the o-, m- or p-position of nitrobenzaldehyde and the backbone, which was never observed in homogeneous aldol addition.


Asunto(s)
Alcaloides de Cinchona/química , Organofosfonatos/química , Circonio/química , Aldehídos/química , Catálisis , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión
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