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1.
Molecules ; 28(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37110871

RESUMEN

In this paper, a novel phosphorus-doped sulfur quantum dots (P-SQDs) material was prepared using a simple hydrothermal method. P-SQDs have a narrow particle size distribution as well as an excellent electron transfer rate and optical properties. Compositing P-SQDs with graphitic carbon nitride (g-C3N4) can be used for photocatalytic degradation of organic dyes under visible light. More active sites, a narrower band gap, and stronger photocurrent are obtained after introducing P-SQDs into g-C3N4, thus promoting its photocatalytic efficiency by as much as 3.9 times. The excellent photocatalytic activity and reusability of P-SQDs/g-C3N4 are prospective signs of its photocatalytic application under visible light.

2.
Molecules ; 28(10)2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37241896

RESUMEN

Photocatalysis holds great promise for addressing water pollution caused by organic dyes, and the development of Ag2O/Fe3O4 aims to overcome the challenges of slow degradation efficiency and difficult recovery of photocatalysts. In this study, we present a novel, environmentally friendly Ag2O/Fe3O4 magnetic nanocomposite synthesized via a simple coprecipitation method, which not only constructs a type II heterojunction but also successfully couples photocatalysis and Fenton reaction, enhancing the broad-spectrum response and efficiency. The Ag2O/Fe3O4 (10%) nanocomposite demonstrates exceptional degradation performance toward organic dyes, achieving 99.5% degradation of 10 mg/L methyl orange (MO) within 15 min under visible light irradiation and proving its wide applicability by efficiently degrading various dyes while maintaining high stability over multiple testing cycles. Magnetic testing further highlighted the ease of Ag2O/Fe3O4 (10%) recovery using magnetic force. This innovative approach offers a promising strategy for constructing high-performance photocatalytic systems for addressing water pollution caused by organic dyes.

3.
Chembiochem ; 23(14): e202200217, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35575966

RESUMEN

Impaired mitophagy hinders the clearance of damaged mitochondria, inducing pathological states. Knowledge of this phenomenon is key to diagnosing certain diseases and understanding their pathogenesis. Mitophagy involves an acidization process that could serve as an ideal detection target. In this work, we designed and synthesized a mitochondrial-targeting fluorescence probe, Z2, for evaluating pH variation. This probe exhibited remarkable "turn-on" fluorescence under acidic conditions. In biological applications, Z2 showed a strong, specific pH detection capacity in Parkin-overexpressing HeLa cells during the mitophagy process. The "turn-on" fluorescence property of Z2 was also used to detect pH variations in Caenorhabditis elegans. This probe, as a novel pH assessment tool, may facilitate further research of mitophagy-associated pathological patterns.


Asunto(s)
Colorantes Fluorescentes , Mitofagia , Animales , Caenorhabditis elegans , Colorantes Fluorescentes/química , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Mitocondrias , Pirimidinas , Ubiquitina-Proteína Ligasas
4.
Molecules ; 23(2)2018 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-29470399

RESUMEN

A selective and ratiometric turn-on fluorescent probe was designed and synthesized by using a novel dicyanoisophorone-based derivative and acrylate moiety. The probe displayed high stability and good selectivity to cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). It also exhibited rapid response to Cys within 180 s. Most importantly, the fluorescence intensity ratio at 590 and 525 nm (I590/I525) was linearly dependent on the Cys concentration in the range from 0 to 40 µM and the detection limit calculated to be 0.48 µM. This probe was also applied for bioimaging of intracellular Cys in living HeLa cells with low cytotoxicity.


Asunto(s)
Cisteína/aislamiento & purificación , Colorantes Fluorescentes/química , Isocianatos/química , Imagen Molecular , Acrilatos/química , Cisteína/química , Glutatión/química , Glutatión/aislamiento & purificación , Homocisteína/química , Homocisteína/aislamiento & purificación , Humanos
5.
Sensors (Basel) ; 17(10)2017 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-28946632

RESUMEN

Avoiding vehicle-to-pedestrian crashes is a critical requirement for nowadays advanced driver assistant systems (ADAS) and future self-driving vehicles. Accordingly, detecting pedestrians from raw sensor data has a history of more than 15 years of research, with vision playing a central role. During the last years, deep learning has boosted the accuracy of image-based pedestrian detectors. However, detection is just the first step towards answering the core question, namely is the vehicle going to crash with a pedestrian provided preventive actions are not taken? Therefore, knowing as soon as possible if a detected pedestrian has the intention of crossing the road ahead of the vehicle is essential for performing safe and comfortable maneuvers that prevent a crash. However, compared to pedestrian detection, there is relatively little literature on detecting pedestrian intentions. This paper aims to contribute along this line by presenting a new vision-based approach which analyzes the pose of a pedestrian along several frames to determine if he or she is going to enter the road or not. We present experiments showing 750 ms of anticipation for pedestrians crossing the road, which at a typical urban driving speed of 50 km/h can provide 15 additional meters (compared to a pure pedestrian detector) for vehicle automatic reactions or to warn the driver. Moreover, in contrast with state-of-the-art methods, our approach is monocular, neither requiring stereo nor optical flow information.


Asunto(s)
Accidentes de Tránsito/prevención & control , Inteligencia Artificial , Conducción de Automóvil , Peatones/psicología , Humanos , Intención , Caminata
6.
Sensors (Basel) ; 16(6)2016 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-27271635

RESUMEN

Despite all the significant advances in pedestrian detection brought by computer vision for driving assistance, it is still a challenging problem. One reason is the extremely varying lighting conditions under which such a detector should operate, namely day and nighttime. Recent research has shown that the combination of visible and non-visible imaging modalities may increase detection accuracy, where the infrared spectrum plays a critical role. The goal of this paper is to assess the accuracy gain of different pedestrian models (holistic, part-based, patch-based) when training with images in the far infrared spectrum. Specifically, we want to compare detection accuracy on test images recorded at day and nighttime if trained (and tested) using (a) plain color images; (b) just infrared images; and (c) both of them. In order to obtain results for the last item, we propose an early fusion approach to combine features from both modalities. We base the evaluation on a new dataset that we have built for this purpose as well as on the publicly available KAIST multispectral dataset.

7.
Clin Respir J ; 18(7): e13793, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38979664

RESUMEN

One hundred eighty pairs of tissues of esophageal squamous cell carcinoma (ESCC) were tested by the transcriptome sequencing in order to explore etiology factors. The chi-square test and correlation analysis demonstrated that the relative expression levels of keratin 17 (KRT17) and collagen type I α1 chain (COL1A1) were significantly higher in EC with diabetes. Expression of KRT17 was correlated with blood glucose (r = 0.204, p = 0.001) and tumor size (r = -0.177, p = 0.038) in patients. COL1A1 correlated with age (r = -0.170, p = 0.029) and blood glucose levels (r = 0.190, p = 0.015). Experimental results of qRT-PCR: KRT17 and COL1A1 genes were highly expressed in ESCC (p < 0.05). When the two genes were used as a combination test, the positive detection rate of EC was 90.6%, and the ROC curve had greater power. The KRT17 and COL1A1 genes had the potential to be biomarkers for the diagnosis of ESCC.


Asunto(s)
Biomarcadores de Tumor , Cadena alfa 1 del Colágeno Tipo I , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Queratina-17 , Humanos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo , Masculino , Femenino , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Persona de Mediana Edad , Queratina-17/genética , Queratina-17/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Anciano , Regulación Neoplásica de la Expresión Génica
8.
Gels ; 10(3)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38534617

RESUMEN

Gel electrolytes for lithium-ion batteries continue to replace the organic liquid electrolytes in conventional batteries due to their advantages of being less prone to leakage and non-explosive and possessing a high modulus of elasticity. However, the development of gel electrolytes has been hindered by their generally low ionic conductivity at room temperature and high interfacial impedance with electrodes. In this paper, a poly (vinylidene fluoride)-hexafluoropropylene copolymer (PVdF-HFP) with a flexible structure, Li6PS5Cl (LPSCl) powder of the sulfur-silver-germanium ore type, and lithium perchlorate salt (LiClO4) were prepared into sulfide gel composite electrolyte films (GCEs) via a thermosetting process. The experimental results showed that the gel composite electrolyte with 1% LPSCl in the PVdF-HFP matrix exhibited an ionic conductivity as high as 1.27 × 10-3 S·cm-1 at 25 °C and a lithium ion transference number of 0.63. The assembled LiFePO4||GCEs||Li batteries have excellent rate (130 mAh·g-1 at 1 C and 54 mAh·g-1 at 5 C) and cycling (capacity retention was 93% after 100 cycles at 0.1 C and 80% after 150 cycles at 0.2 C) performance. This work provides new methods and strategies for the design and fabrication of solid-state batteries with high ionic conductivity and high specific energy.

9.
Adv Mater ; : e2405890, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39045923

RESUMEN

Mild-hyperthermia photothermal therapy (mPTT) has therapeutic potential with minimized damage to normal tissues. However, the poorly vascularized tumor area severely hampers the penetration of photothermal agents (PTAs), resulting in their heterogeneous distribution and the subsequent heterogeneous local temperature during mPTT. The presence of regions below the therapeutic 42 °C threshold can lead to incomplete tumor ablation and potential recurrence. Additionally, tumor anti-apoptosis and cytoprotection pathways, particularly activated thermoresistance, can nullify mild hyperthermia-induced tumor damage. Therefore, a bioinspired photosensitizer decorated with leucine to form biomimetic nanoclusters (CP-PLeu nanoparticles (NPs)) aimed at achieving rapid and homogeneous accumulation in tumors, is introduced. Moreover, CP-PLeu exhibits photodynamic effects that reverse tumor thermoresistance and physiological repair mechanisms, thereby inhibiting tumor resistance to hyperthermia. With the addition of NIR-II laser irradiation, CP-PLeu optimizes the therapeutic efficacy of mPTT and contributes to a minimally invasive therapeutic process for breast cancer. This therapeutic strategy, utilizing a biomimetic photosensitizer for homogeneous distribution of therapeutic temperature and photoactivated reversal of tumor thermoresistance, successfully achieves efficient breast tumor inhibition through an atraumatic mPTT process.

10.
J Affect Disord ; 364: 157-166, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39147147

RESUMEN

BACKGROUND: Suicidal ideation (SI) assumes a pivotal role in predicting suicidal behaviors. The incidence of SI among high (junior and senior) school students is significantly higher than that of other age groups. The aim of this study is to explore the gender differences in SI among high school students in Yunnan Province. METHOD: A total of 6180 students in grades 7-12 in Yunnan province, China from May 2021 to May 2022 participated in this survey. Univariate analysis was employed to describe the influencing factors of male and female students' SI. Subsequently, data were stratified by gender. Adopting machine learning technique, including Least Absolute Shrinkage and Selection Operator (Lasso) and Boruta algorithm, and logistic regression model to estimate the direction and effect magnitude of the influencing factors. RESULTS: The prevalence of SI was significantly higher for females (31.34 %) than males (16.73 %). The logistic regression model was established using the variables screened by Boruta algorithm, indicated that anxiety, depression, suffering emotion abuse or emotion neglect in childhood, non-suicidal self-injury, evening chronotype are common risk factors for SI in male and female students. Notably, female students who exhibited aggressive behavior, have experienced bullying, and were in the junior high school learning stage were more likely to report SI than their male counterparts. CONCLUSIONS: Females showed more vulnerability to SI than males especially among females in junior high school, reporting aggressive behavior and bullying experiences. Tailored prevention strategies, informed by these gender-related distinctions, should be developed and implemented.


Asunto(s)
Aprendizaje Automático , Estudiantes , Ideación Suicida , Humanos , Femenino , Masculino , China/epidemiología , Adolescente , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Factores Sexuales , Factores de Riesgo , Acoso Escolar/estadística & datos numéricos , Prevalencia , Depresión/epidemiología , Depresión/psicología , Ansiedad/epidemiología , Ansiedad/psicología , Encuestas y Cuestionarios , Instituciones Académicas , Modelos Logísticos
11.
Adv Mater ; 35(35): e2301901, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37079477

RESUMEN

Photothermal therapy (PTT) has received increasing interest in cancer therapeutics owing to its excellent efficacy and controllability. However, there are two major limitations in PTT applications, which are the tissue penetration depth of lasers within the absorption range of photothermal agents and the unavoidable tissue empyrosis induced by high-energy lasers. Herein, a gas/phototheranostic nanocomposite (NA1020-NO@PLX) is engineered that integrates the second near-infrared-peak (NIR-II-peak) absorbing aza-boron-dipyrromethenes (aza-BODIPY,NA1020) with the thermal-sensitive nitric oxide (NO) donor (S-nitroso-N-acetylpenicillamine, SNAP). An enhanced intramolecular charge transfer mechanism is proposed to achieve the NIR-II-peak absorbance (λmax = 1020 nm) on NA1020, thereby obtaining its deep tissue penetration depth. The NA1020 exhibits a remarkable photothermal conversion, making it feasible for the deep-tissue orthotopic osteosarcoma therapy and providing favorable NIR-II emission to precisely pinpoint the tumor for a visible PTT process. The simultaneously investigated atraumatic therapeutic process with an enhanced cell apoptosis mechanism indicates the feasibility of the synergistic NO/low-temperature PTT for osteosarcoma. Herein, this gas/phototheranostic strategy optimizes the existing PTT to present a repeatable and atraumatic photothermal therapeutic process for deep-tissue tumors, validating its potential clinical applications.


Asunto(s)
Neoplasias Óseas , Nanocompuestos , Nanopartículas , Neoplasias , Osteosarcoma , Humanos , Donantes de Óxido Nítrico , Fototerapia , Nanocompuestos/uso terapéutico , Línea Celular Tumoral
12.
Front Endocrinol (Lausanne) ; 13: 968984, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992141

RESUMEN

Background: Tumor metabolism is important for cancer progression. Nevertheless, the role of the metabolism pathway and related molecules in nasopharyngeal carcinoma (NPC) is limited. Methods: Open-accessed data was downloaded from The Cancer Genome Atlas database. All the analysis was performed using the R software and the package in R environments. Results: In our study, we firstly explored the role of 21 metabolism-related pathways in NPC patients. We found that the steroid biosynthesis and biosynthesis of unsaturated fatty acids were risk factors, while the alpha linolenic acid metabolism was a protective factor. Then, the alpha linolenic acid metabolism aroused our interest. A total of 128 differentially expressed genes (DEGs) were identified, including 71 downregulated and 57 upregulated genes identified between high and low alpha linolenic acid metabolism level. Based on these DEGs, we constructed a prognosis model including DEFB4B, FOXL2NB, MDGA2, RTL1, SLURP2, TMEM151B and TSPAN19, which showed great prediction efficiency in both training and validation cohorts. Clinical correlation analysis showed that high-risk patients might have worse clinical pathology parameters. Pathway enrichment analysis showed that riskscore was positively correlated with angiogenesis, DNA repair, G2/M checkpoints, IL6/JAK/STAT3 signaling, KRAS signaling up, WNT beta-catenin signaling, PI3K/AKT/mTOR signaling, yet positively correlated with inflammatory response, xenobiotic metabolism, TNF-α signaling via NFKB and interferon-gamma response. Immune infiltration analysis showed that the riskscore was positively correlated with the M2 and M0 macrophages, but negatively correlated with neutrophils, plasma cells, follicular helper T cells and resting dendritic cells Moreover, we found that the low-risk patients might be more sensitive to immunotherapy and lapatinib. Conclusions: In all, our study identified the genes associated with alpha linolenic acid metabolism and constructed an effective prognosis model which could robustly predict NPC patients prognosis.


Asunto(s)
Neoplasias Nasofaríngeas , Ácido alfa-Linolénico , Perfilación de la Expresión Génica , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Fosfatidilinositol 3-Quinasas/genética , Pronóstico , Microambiente Tumoral/genética
13.
Pathol Oncol Res ; 28: 1610481, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36052378

RESUMEN

Oral squamous cell carcinoma (OSCC) is a common head-and-neck cancer with a deficiency of early diagnosis and poor prognosis. To identify potential diagnostic and prognostic markers of OSCC, we firstly used weighted gene co-expression network analysis (WGCNA) to build a co-expression module from GSE42743. Next, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on specified units from selected modules utilizing Database for Annotation, Visualization, and Integrated Discovery (DAVID). Additionally, we identified and validate hub genes of these specified modules from multiple datasets like GEPIA and TCGA. In total 16 co-expression modules were built by 17,238 genes of 74 tumor samples utilizing WGCNA. Through pathway and functional enrichment analysis, the turquoise module was most firmly relevant to the cell cycle, oocyte meiosis, and p53 signaling pathway. Hub genes VRK1, NUP37, HMMR, SPC25, and RUVBL1 were identified to be related to oral cancer at both molecular level and clinical levels. The expressions of these genes differed in tumor tissues and normal tissues. Meanwhile, patients with high hub gene expression had a poor prognosis clinically. To conclude, five hub genes were identified to be relevant to oral cancer from the molecular level and the clinical level. Therefore, the detection of these genes was of great significance. They can be regarded as diagnostic and prognostic biomarkers for oral cancer. Also, they could shed light on the improvement of patients' overall survival and prognosis, which needs further analysis in the future.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Perfilación de la Expresión Génica , Redes Reguladoras de Genes/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias de la Boca/genética , Proteínas Serina-Treonina Quinasas , Carcinoma de Células Escamosas de Cabeza y Cuello/genética
14.
Biosens Bioelectron ; 210: 114328, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35512583

RESUMEN

Optical flexible biosensors are novel sensors fabricated on flexible or ductile materials that are used for the detection of analytes. Compared to traditional sensors, these biosensors offer greater flexibility, which allows them to adapt to different working environments, to meet the deformation requirements of humans. Flexible devices can not only detect alterations in analytes in vitro, but can also realize real-time and non-invasive monitoring of the variation of physical conditions or metabolites in vivo. Flexible devices are earning increasing attention from researchers and clinicians. In the present review, we summarize and introduce the detection principles, key analytes, and applications of optical flexible biosensors in the diagnosis/treatment of diseases as well as health detection. Moreover, the remaining challenges of flexible devices and their perspectives have also been addressed. We hope that this review will pave ways for the development of more feasible and multifunctional flexible devices.


Asunto(s)
Técnicas Biosensibles , Dispositivos Electrónicos Vestibles , Humanos
15.
Sci Rep ; 12(1): 20284, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36434082

RESUMEN

According to the serious problem of sulfur dioxide pollution, montmorillonite is one of the effective ways in gas pollution control because of its excellent absorption properties. One of the fundamental questions is to fully understand sulfur dioxide absorption mechanism of montmorillonite. In this study, using the first-principle methods, we studied the adsorption characteristics of Ca-montmorillonite in the presence of [Formula: see text]. The adsorption energy and elasticity constants as a function of the adsorption capacity were also studied. The calculated results show that bridge site is the most stable adsorption site for [Formula: see text] with the adsorption energy of - 140 meV. As adsorbent, Ca-montmorillonite is a clay with layer-structure, most of bond lengths(such as Al-O, Mg-O, Si-O, and H-O) does not obviously change. As adsorbed gas, the O-S-O bond angle of adsorbed [Formula: see text] change from [Formula: see text] to [Formula: see text]. The volume and adsorption energies of Ca-montmorillonite almost increase linearly with increasing [Formula: see text] adsorption. By calculating the montmorillonite elasticity constants under different adsorption capacity, we found that the elasticity constant C33 which perpendicular to the crystal face, with the maximum changes from 450 to 326 GPa. In addition, Young's modulus,bulk modulus and shear modulus significantly decrease with the increasing adsorption. The calculated results will not only help to understand the physical and chemical of montmorillonite but may also provide theoretical guidance for dealing with the problem of gas pollution.

16.
Cogn Neurodyn ; 15(1): 181-189, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33786088

RESUMEN

Deep learning has achieved great success in areas such as computer vision and natural language processing. In the past, some work used convolutional networks to process EEG signals and reached or exceeded traditional machine learning methods. We propose a novel network structure and call it QNet. It contains a newly designed attention module: 3D-AM, which is used to learn the attention weights of EEG channels, time points, and feature maps. It provides a way to automatically learn the electrode and time selection. QNet uses a dual branch structure to fuse bilinear vectors for classification. It performs four, three, and two classes on the EEG Motor Movement/Imagery Dataset. The average cross-validation accuracy of 65.82%, 74.75%, and 82.88% was obtained, which are 7.24%, 4.93%, and 2.45% outperforms than the state-of-the-art, respectively. The article also visualizes the attention weights learned by QNet and shows its possible application for electrode channel selection.

17.
J Mater Chem B ; 9(28): 5583-5598, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34161402

RESUMEN

Gold nanomaterials have potential applications in biosensors and biomedicine due to their controllable synthesis steps, high biocompatibility, low toxicity and easy surface modification. However, there are still various limitations including low water solubility and stability, which greatly affect their applications. In addition, some synthetic methods are very complicated and costly. Therefore, huge efforts have been made to improve their properties. This review mainly introduces the strategies for surface modification of gold nanomaterials, such as amines, biological small molecules and organic small molecules as well as the biological applications of these functionalized AuNPs. We aim to provide effective ideas for better functionalization of gold nanomaterials in the future.


Asunto(s)
Investigación Biomédica , Oro/química , Nanopartículas del Metal/química , Propiedades de Superficie
18.
Acta Chim Slov ; 67(3): 812-821, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33533441

RESUMEN

A series of N-alkylated deoxynojirimycin (DNJ) derivatives connected to a terminal tertiary amine at the alkyl chains of various lengths were prepared. These novel synthetic compounds were assessed for preliminary glucosidase inhibition and anticancer activities in vitro. Potent and selective inhibition was observed among them. Compound 7d (IC50 = 0.052 mM) showed improved and selective inhibitory activity against ?-glucosidase compared to DNJ (IC50 = 0.65 mM). In addition, analysis of the kinetics of enzyme inhibition by using Lineweaver-Burk plots indicated that 7d inhibited ?-glu-cosidase in a competitive manner, suggesting that 7d was expected to bind to the active site of ?-glucosidase. Compounds 8b and 8c were found to be moderate and selective inhibitors of ?-glucosidase. Nevertheless, none of compounds inhib-ited the growth of B16F10 melanoma cells.


Asunto(s)
1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/farmacología , Aminas/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , 1-Desoxinojirimicina/síntesis química , Aminas/síntesis química , Animales , Línea Celular Tumoral , Celulasas/antagonistas & inhibidores , Pruebas de Enzimas , Inhibidores de Glicósido Hidrolasas/síntesis química , Cinética , Ratones , alfa-Glucosidasas/química
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 193: 226-234, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29247919

RESUMEN

Two new sugar-rhodamine fluorescent probes (RDG1 and RDG2) have been synthesized and characterized by 1H NMR, 13C NMR and HRMS. Their UV-Vis, fluorescence spectra and fluorescence-response to Fe3+ are investigated and discussed. RDG1 had a very nice linear relationship between UV absorbance and Fe3+ concentration with the correlation coefficient as high as 0.997 and the detection limit is 3.46×10-6M. Upon the addition of Fe3+, the spirolactam ring of RDG1 was opened and a 1:1 metal ligand complex was formed from Job's plot. The results showed that RDG1 can be used as an effective fluorescent probe for selective detection of Fe3+ in water. RDG2 was incorporated the well-known rhodamine group and a water-soluble d-glucose group within one molecule and can be used for detecting Fe3+ in natural water as a selective fluorescent sensor. The addition of Fe3+ into RDG2 resulted in a strongly enhanced fluorescence as well as color change of solution from colorless to pink. Job's plot of RDG2 indicated 1:1 stoichiometry of RDG2-Fe3+. RDG2 can serve as a probe for Fe3+ between pH=4.0 to 7.0 and it's detection limit is 2.09×10-6M. The OFF-ON fluorescent mechanisms of RDG1-Fe3+ and RDG2-Fe3+ are proposed.

20.
Acta Chim Slov ; 65(3): 611-620, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-33562910

RESUMEN

Protecting groups play an important role in the carbohydrate chemistry and considerably influence the reactivity of substrate. A study of the substitution of various protecting groups in 1-deoxynojirimycin was carried out. Substrate N-benzyloxycarbonyl- 1,5-dideoxy-1,5-imino-4,6-O-isopropylidene-D-glucitol was subjected to alkylation at positions 2- and 3- to obtain di-substituted products and N-Cbz group was selectively removed by using NaOH in EtOH/H2O. Regioselective benzoylation and alkylation of N-benzyloxycarbonyl-1,5-dideoxy-1,5-imino-4,6-O-isopropylidene-D-glucitol were conducted under the action of TBAB-NaOH catalytic system. It was found that all protected and mono-protected analogs form simultaneously and their structures were confirmed by spectroscopic means. The results showed that electrophiles play an important role in determining the product distribution.

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