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1.
Molecules ; 29(3)2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38338463

RESUMEN

Here, we report the synthesis of adamantane-based macrocycle 2 by combining adamantane building blocks with π-donor 1,3-dimethoxy-benzene units. An unpredictable keto-adamantane-based macrocycle 3 was obtained by the oxidation of 2 using DDQ as an oxidant. Moreover, a new type of macrocyclic molecule-based CT cocrystal was prepared through exo-wall CT interactions between 3 and DDQ. The cocrystal material showed selective vapochromism behavior towards THF, specifically, among nine volatile organic solvents commonly used in the laboratory. Powder X-ray diffraction; UV-Vis diffuse reflectance spectroscopy; 1H NMR; and single crystal X-ray diffraction analyses revealed that color changes are attributed to the vapor-triggered decomplexation of cocrystals.

2.
Molecules ; 28(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37375339

RESUMEN

In this study, we explorethe synthesis of binaphthyl-based chiral macrocyclic hosts for the first time. They exhibited the selective recognition abilities of iodide anions which can be favored over those of other anions (AcO-, NO3-, ClO4-, HSO4-, Br-, PF6-, H2PO4-, BF4-, and CO3F3S-), as confirmed by UV-vis, HRMS, and 1H NMR spectroscopy experiments, as well as DFT calculations. Neutral aryl C-H···anion interactions play an important role in the formation complexes. The recognition process can be observed by the naked eye.

3.
Molecules ; 28(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36838835

RESUMEN

A turn-on fluorescent probe, cage 1, was efficiently self-assembled by condensing 4,4'-(benzothiadiazole-4,7-diyl)dibenzaldehyde and TREN in chloroform. The formation of cage 1 was characterized and confirmed by NMR spectroscopy, mass spectrometry, and theoretical calculations. The yield of cage 1 could be controlled by tuning the reaction conditions, such as the precursor concentration. Interestingly, the addition of 10 equiv of Cd2+ relative to cage 1 could increase the fluorescence almost seven-fold. 1H NMR and fluorescence experiments indicating fluorescence enhancement may be caused by the decomposition of cage 1. Such a high selectivity toward Cd2+ implies that the cage could potentially be employed in cadmium detection.


Asunto(s)
Cadmio , Tiadiazoles , Cadmio/química , Microscopía Fluorescente/métodos , Cloroformo , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos
5.
Sci Rep ; 12(1): 19338, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36369247

RESUMEN

To investigate the effectiveness of long-term Baduanjin and aerobic training on the 10-year risk of atherosclerotic cardiovascular disease in prediabetic patients. This study was single-blind randomized controlled trial. A total of 98 participants with prediabetes were randomly divided into three groups: the BDJ (n = 34), AT (n = 32), and control (n = 32) groups. Participants in the BDJ and AT groups underwent one year of supervised group exercise, consisting of 60 min/session every other day. The primary outcomes were metabolic control and the 10-year risk of ASCVD. The secondary outcome was a change in blood glucose status. After the intervention, various metabolic indexes were significantly improved in the two exercise groups relative to the control group and baseline measurements (p < 0.05). Compared with no exercise, BDJ and AT had significant preventive and protective effects against the risk of ASCVD in patients with prediabetes (p < 0.001). The overall effects of the two exercise groups were similar (p > 0.05). Long-term BDJ training can effectively reduce the risk of type 2 diabetes mellitus (T2DM) and its cardiovascular complications in prediabetic patients. The effect of BDJ is similar to that of moderate-intensity aerobic exercise.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Estado Prediabético , Humanos , Estado Prediabético/complicaciones , Estado Prediabético/terapia , Estado Prediabético/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Método Simple Ciego , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Ejercicio Físico
7.
ACS Synth Biol ; 11(1): 85-91, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-35006674

RESUMEN

Nosiheptide (NOS), a potent bactericidal thiopeptide, belongs to a class of natural products produced by ribosomal synthesis and post-translational modifications, and its biosynthetic pathway has largely been elucidated. However, the central trithiazolylpyridine structure of NOS remains inaccessible to structural changes. Here we report the creation of a NOS analogue containing a unique selenazole ring by the construction of an artificial system in Streptomyces actuosus ATCC25421, where the genes responsible for the biosynthesis of selenoprotein from Escherichia coli and the biosynthetic gene cluster of NOS were rationally integrated to produce a selenazole-containing analogue of NOS. The thiazole at the fifth position in NOS was specifically replaced by a selenazole to afford the first selenazole-containing "unnatural" natural product. The present strategy is useful for structural manipulation of various RiPP natural products.


Asunto(s)
Péptidos , Tiazoles , Vías Biosintéticas/genética , Familia de Multigenes , Péptidos/metabolismo , Tiazoles/química , Tiazoles/metabolismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-34471419

RESUMEN

To explore the main active components and effects of cell cycle regulation mechanism of Astragali radix (AR) and Angelicae sinensis radix (ASR) on oxidative damage in vascular endothelial cells, a model of oxidative damage in human umbilical vein endothelial cells (HUVECs) induced by oxidized low-density lipoprotein (ox-LDL) treatment was developed. Based on the "knock-out/knock-in" model of the target component, cell viability, intracellular reactive oxygen species (ROS), and lactate dehydrogenase (LDH) leakage were assessed by Cell Counting Kit-8 assay, fluorescent probe 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA), and colorimetric assay, respectively, to evaluate the protective effect of the active components of AR and ASR (astragaloside IV (AS IV), astragaloside I (AS I), formononetin (FRM), calycosin (CAL), calycosin-7-O-ß-D glucoside (CLG), and ferulic acid (FRA)) against oxidative damage. The cell cycle and expression of genes encoding cyclins and cyclin-dependent kinases (CDKs) were observed using flow cytometry and quantitative real-time polymerase chain reaction. The results showed that the combination of active components (ACC) significantly inhibited the decrease in cell viability as well as the increase in ROS and LDH release in HUVECs induced by ox-LDL treatment. AS IV and FRM promoted the proliferation of HUVECs but the proliferation index was decreased in the AS I and FRA groups; this inhibitory effect was counteracted by the ACC. The ACC reduced and increased the proportion of positive cells in G1 and S phases, respectively, followed by the upregulation of cyclin A (CCNA), cyclin E (CCNE), and CDK2 mRNA expression and downregulation of cyclin B (CCNB), cyclin D1 (CCND1), CDK1, CDK4, and CDK6 mRNA expression, which significantly mitigated inhibition of HUVECs proliferation induced by ox-LDL treatment. Taken together, AS IV, AS I, FRM, CAL, CLG, and FRA were the primary pharmacodynamic substances of AR and ASR that alleviated oxidative injury in HUVECs. ACC mitigated the upregulation of intracellular ROS levels and LDH release induced by ox-LDL treatment, which promoted the cell cycle procession of HUVECs by regulating the expression of genes encoding cyclins and CDKs and thus preventing oxidative damage in HUVECs.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 201: 216-222, 2018 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-29753966

RESUMEN

A fluorescence probe based on thiosemicarbazide has been synthesized and well characterized by 1H NMR, 13C NMR, Elemental analysis, Electrospray ionization mass spectra. The probe 1 functions as a multitarget ion sensor, detect biologically and ecologically important Cd2+, PO43- and Cr3+. Meanwhile, probe 1 displays selectivity for Cd2+ over other metal ions and anions in DMF by emission spectrum. Interestingly, probe 1 has been explored to recognize PO43- in CH3OH-H2O (v:v = 1:9). The binding stoichiometry of probe 1 with Cd2+ and PO43- are 2:1 and 1:1, respectively, which are confirmed by Electrospray ionization mass spectra. Probe 1 is selective, sensitive and reversibility/reusability to Cd2+ and PO43- with the detection limit as low as 0.035 µM and 0.011 µM respectively. Besides, the designed probe 1 has shown potential applications in the area of photo-printing.

10.
Nanoscale ; 7(32): 13734-46, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26219748

RESUMEN

The electronic and magnetic properties of transition metal (TM = Sc, Ti, V, Cr and Mn) atom incorporated single and double one-dimensional (1D) styrene molecular wires confined on the hydrogen-terminated Si(100) surface are explored for the first time by means of spin-polarized density functional theory, denoted as Si-[TM(styrene)]. It is unveiled that TM atoms bind asymmetrically to the adjacent phenyl rings, which leads to novel electronic and magnetic properties in stark contrast to the well-studied gas phase TM-benzene molecular wires. Si-[Mn(styrene)]∞ and Si-[Cr(styrene)]∞ single molecular wires (SMWs) are a ferromagnetic semiconductor and half metal, respectively. Creation of H-atom defects on the silicon surface can introduce an impurity metallic band, which leads to novel half-metallic magnetism of a Si-[Mn(styrene)]∞ system. Moreover, double molecular wires (DMWs) containing two identical or hetero SMWs are theoretically designed. The [Mn(styrene)]∞-[Cr(styrene)]∞ DMW exhibits half-metallic magnetism where the spin-up and spin-down channels are contributed by two single molecular wires. Finally, we demonstrate that introducing a TM-defect may significantly affect the electronic structure and magnetic properties of molecular wires. These studies provide new insights into the structure and properties of surface supported 1-D sandwiched molecular wires and may inspire the future experimental synthesis of substrate confined organometallic sandwiched molecular wires.

11.
Genet Test Mol Biomarkers ; 19(8): 439-43, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26076219

RESUMEN

BACKGROUND: Genome-wide association studies have validated the RAS guanyl nucleotide-releasing protein 1 (RASGRP1) gene as a type 2 diabetes (T2D) susceptibility locus. AIMS: This study aimed to replicate and verify the association of RASGRP1 tag single-nucleotide polymorphisms with T2D in a Chinese Han population. METHODS: Eleven common variants of RASGRP1 were detected using TaqMan technology in 1272 healthy controls and 1234 T2D patients. All study participants were unrelated members of the Han ethnic group in China. In this study, the rs7403531 genotype frequency differed significantly between T2D patients and controls (allele: adjusted p=8.30×10(-6), genotype: adjusted p=2.50×10(-5), OR=1.366 [95% CI=1.206-1.546]). The rs4465567-rs4567661 C-A and C-C haplotypes were also significant risk factors for T2D (adjusted p=0.0002 and p=0.0006, respectively) with a global p-value of 6.46×10(-5). These results indicate that in a Chinese Han population, RASGRP1 variants, particularly rs7403531, confer a risk for developing T2D.


Asunto(s)
Pueblo Asiatico/genética , Proteínas de Unión al ADN/genética , Diabetes Mellitus Tipo 2/genética , Factores de Intercambio de Guanina Nucleótido/genética , Adulto , Estudios de Casos y Controles , China , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores de Riesgo
12.
J Am Chem Soc ; 135(7): 2583-95, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23343464

RESUMEN

We have systematically studied the CO oxidation on various nanosized gold clusters with sizes ranging from 0.3 to 0.8 nm on the basis of density functional theory (DFT) calculations. A hitherto unreported trimolecular Langmuir-Hinshelwood (LH) mechanism is proposed, which offers new insights into the fundamental mechanism for CO oxidation on nanosized gold clusters. Specifically, we find that the coadsorbed CO molecule at a unique triangular Au(3) active site can act as a promoter for the scission of an O-O bond, leading to the spontaneous formation (due to extremely low energy barrier) of two CO(2) molecules as product. The key step to the O-O bond scission in the OCOO* intermediate is significantly accelerated due to the electrophilic attack of the coadsorbed neighboring CO molecule on the triangular Au(3) site. This new mechanism is called CO self-promoting oxidation, which can be visualized in real time from the trajectory of a Born-Oppenheimer molecular dynamics (BOMD) simulation. We also find that such CO self-promoting oxidation is quite universal, as long as the triangular Au(3) reaction site is available. This is demonstrated in two prototype metal oxide supported gold nanostructure systems: namely, Au(n)/MgO and bilayer-Au/TiO(2). The coadsorbed CO can not only serve as a promoter for its own oxidation but also promote other oxidation reactions such as styrene oxidation through expediting O-O scission on gold nanostructures.

13.
Yi Chuan ; 34(12): 1537-44, 2012 Dec.
Artículo en Chino | MEDLINE | ID: mdl-23262100

RESUMEN

Diabetic nephropathy (DN) is one of the most serious chronic complications of diabetes mellitus. The observed incidence patterns in different ethnics and familial clustering have suggested that the genetic factor plays an important role in the development and progression of DN. This paper reviews the recent advances on genetics of DN, including candidate genes association studies, linkage studies and genome-wide association studies (GWASs). Candidate genes association studies and meta-analysis showed that a few candidate genes have been reproducibly associated with DN, such as ACE, AGT and PPARG genes. Linkage studies and genome-wide linkage studies have also identified susceptibility chromosomal loci. With the development of high-throughput sequencing and chip techniques, GWAS has become an important strategy to identify variants responsible for DN. The genetic factor has been the significant contribution to the pathobiology of DN. However, it is not the only cause of the pathobiology of DN, because the environment factor also influences the pathobiology of DN. Nonetheless, genetic studies may provide valuable information for the pathobiology of nephropathy and potential targets of its treatment.


Asunto(s)
Nefropatías Diabéticas/genética , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Humanos
14.
Xenobiotica ; 41(4): 290-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21319959

RESUMEN

The absorption and transport mechanisms of berberine, palmatine, jateorhizine, and coptisine were studied using a Caco-2 cells uptake and transport model, with the addition of cyclosporin A and verapamil as P-glycoprotein (P-gp) inhibitors and MK-571 as a multidrug resistance-associated protein 2 (MRP(2)) inhibitor. In the uptake experiment, berberine, palmatine, jateorhizine, and coptisine were all taken into Caco-2 cells, and their uptakes were increased in the presence of cyclosporin A or verapamil. In the transport experiment, P(app) (AP-BL) was between 0.1 and 1.0 × 10(6) cm/sec for berberine, palmatine, jateorhizine, and coptisine and was lower than P(app) (BL-AB). ER values were all >2. Cyclosporin A and verapamil both increased P(app) (AP-BL) but decreased P(app) (BL-AB) for berberine, palmatine, jateorhizine, and coptisine; ER values were decreased by >50%. MK-571 had no influence on the transmembrane transport of berberine, palmatine, jateorhizine, and coptisine. At a concentration of 1-100 µM, berberine, palmatine, jateorhizine, and coptisine had no significant effects on the bidirection transport of Rho123. Berberine, palmatine, jateorhizine, and coptisine were all P-gp substrates; and at the range of 1-100 µM, berberine, palmatine, jateorhizine, and coptisine had no inhibitory effects on P-gp.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Alcaloides de Berberina/metabolismo , Medicamentos Herbarios Chinos/metabolismo , Absorción Intestinal/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Berberina/análogos & derivados , Berberina/metabolismo , Transporte Biológico/efectos de los fármacos , Células CACO-2 , Ciclosporina/metabolismo , Ciclosporina/farmacología , Humanos , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Propionatos/metabolismo , Propionatos/farmacología , Quinolinas/metabolismo , Quinolinas/farmacología , Verapamilo/metabolismo , Verapamilo/farmacología
15.
Zhonghua Gan Zang Bing Za Zhi ; 16(2): 121-4, 2008 Feb.
Artículo en Chino | MEDLINE | ID: mdl-18304429

RESUMEN

OBJECTIVE: To establish an in vitro model applicable for fatty liver lipotoxicity pharmacological research. METHODS: HepG2 cells were cultured with rat serum instead of fetal bovine serum and with long-chain free fatty acid (FFA) added. The tested indices were: the content of serum TNFa, cellular triglycerides (TG) content, Oil Red staining and ultrastructural changes; protein expression and gene expression of cellular TNFa, and the expression and distribution of cathepsin B (Ctsb). RESULTS: After incubation with FFA for 24 hours, the TG deposition of HepG2 in the model group increased markedly and TG content was 627.24 mg/g protein (t = 23.6, P less than 0.01), TNFa content in the cell supernatant also increased to 52.04 pg/mg protein (t = 2.6, P less than 0.05). Compared with those of the normal group, the protein expression and mRNA expression of cellular TNFa and Ctsb also increased significantly. CONCLUSION: FFA could induce a model of HepG2 steatosis with TNFa secretion through the Ctsb signal pathway using rat serum in the culture media. The method is simple and economical, which is an ideal model applicable for fatty liver lipotoxicity pharmacological research.


Asunto(s)
Ácidos Grasos/toxicidad , Factor de Necrosis Tumoral alfa/análisis , Animales , Modelos Animales de Enfermedad , Células Hep G2 , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Triglicéridos/sangre
16.
Chin J Integr Med ; 12(3): 207-11, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17005083

RESUMEN

OBJECTIVE: To study the effect of salvianolic acid B (SAB) and curcumin, the extracts of Salvia Miltiorrhiza and Curcuma Longa, on the proliferation and activation of hepatic stellate cell (HSC), and the extracellular signal regulated kinase (ERK) expression in it. METHODS: Rat's HSC-T6 were cultured and treated by SAB or curcumin. The inhibitory effect on cell proliferation was determined by 3-(4, 5-dimthyl-2-2thiazoly)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) colorimetry, and the expression levels of alpha smooth actin (alpha-SMA), collagen type I, and ERK were determined by Western blot. RESULTS: SAB and curcumin inhibited the proliferation and activation of rat's HSC-T6 in dose-dependent fashion and significantly reduced the expression level of alpha-SMA (P < 0.01). Curcumin significantly reduced the expression of collagen type I (P < 0.05). Both SAB and curcumin showed insignificant effect on the ERK expression level, but they could significantly reduce the level of phosphorylated-ERK expression, showing significant difference as compared with that in the control group (P < 0.01 and P < 0.05 respectively). CONCLUSION: SAB and curcumin could significantly inhibit the proliferation, activation of HSC, and the production of type I collagen in HSC, the mechanism may be associated with their inhibition on ERK phosphorylation.


Asunto(s)
Curcuma , Medicamentos Herbarios Chinos/farmacología , Hepatocitos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Salvia miltiorrhiza , Vasodilatadores/farmacología , Animales , División Celular/efectos de los fármacos , Línea Celular , Matriz Extracelular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Hepatocitos/enzimología , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Fosforilación/efectos de los fármacos , Extractos Vegetales , Ratas
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