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1.
Org Biomol Chem ; 20(43): 8528-8532, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36278495

RESUMEN

Two pairs of unprecedented ß-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2-hi]ß-carboline core with two chiral centers, were isolated from the roots of Peganum harmala. The structures, including their absolute configurations, were identified using spectroscopic analyses and electronic circular dichroism (ECD) calculations. The biosynthetic hypothesis for the formation of pheharmines A-B was proposed. Compounds 1-4 exhibited moderate cytotoxic activities against HL-60 cell lines.


Asunto(s)
Alcaloides , Peganum , Humanos , Peganum/química , Peganum/metabolismo , Morfolinos/análisis , Morfolinos/metabolismo , Semillas , Estructura Molecular , Alcaloides/farmacología , Alcaloides/química , Carbolinas/farmacología , Carbolinas/química
2.
Phytochemistry ; 197: 113107, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35121215

RESUMEN

Six alkaloids peharmalines F-K, along with 14 known ones, were isolated from the aerial part of Peganum harmala L.. The structures of the isolated compounds were determined based on their HR-ESI-MS data, extensive NMR spectroscopic analyses, and ECD calculations. 3-(4-Hydroxyphenyl)quinoline exhibited potent antiproliferative activity against the HepG-2 cell lines with an IC50 value of 3.05 µM. Norharmane displayed a moderate inhibition against A549 and HepG-2 cells with IC50 values of 16.45 µM and 17.27 µM, respectively.


Asunto(s)
Alcaloides , Antineoplásicos Fitogénicos , Peganum , Células A549 , Alcaloides/química , Antineoplásicos Fitogénicos/química , Células Hep G2 , Humanos , Peganum/química , Extractos Vegetales/química
3.
J Healthc Eng ; 2021: 5534607, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35126892

RESUMEN

The prevention and control of nosocomial infection (NI) are becoming increasingly difficult, and its mechanism is becoming increasingly complex. A globally aging population means that an increasing proportion of patients have a susceptible constitution, and the frequent occurrence of severe infectious diseases has also led to an increase in the cost of prevention and control of NI. Medical buildings' spatial environment design for the prevention of NI has been a hot subject of considerable research, but few previous studies have summarized the design criteria for a medical building environment to control the risk of NI. Thus, there is no suitable evaluation framework to determine whether the spatial environment of a medical building is capable of inhibiting the spread of NI. In the context of the global spread of COVID-19, it is necessary to evaluate the performance of the existing medical building environment in terms of inhibiting the spread of NI and to verify current environmental improvement strategies for the efficient and rational use of resources. This study determines the key design elements for the spatial environment of medical buildings, constructs an evaluation framework using exploratory factor analysis, verifies the complex dominant influence relationship, and prioritizes criteria in the evaluation framework using the decision-making trial and evaluation laboratory- (DEMATEL-) based analytical network process (ANP) (DANP). Using representative real cases, this study uses the technique for order preference by similarity to ideal solution (TOPSIS) to evaluate and analyze the performance with the aspiration level of reducing the NI risk. A continuous and systematic transformation design strategy for these real cases is proposed. The main contributions of this study include the following: (1) it creates a systematic framework that allows hospital decision-makers to evaluate the spatial environment of medical buildings; (2) it provides a reference for making design decisions to improve the current situation using the results of a performance evaluation; (3) it draws an influential network relation map (INRM) and the training of influence weights (IWs) for criteria. The sources of practical problems can be identified by the proposed evaluation framework, and the corresponding strategy can be proposed to avoid the waste of resources for the prevention of epidemics.


Asunto(s)
COVID-19 , Infección Hospitalaria , Anciano , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Toma de Decisiones , Humanos , SARS-CoV-2
4.
Org Lett ; 22(19): 7522-7525, 2020 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-32936652

RESUMEN

Two nonbiaryl axially chiral ß-carboline-quinazoline dimers, pegaharmols A (1) and B (2), were isolated from the roots of Peganum harmala. Their planar structures were elucidated by the spectroscopic methods of high-resolution mass spectrometry and 1D and 2D nuclear magnetic resonance (NMR). The stereochemistry was established by a comparison between the experimental data of NMR and electronic circular dichroism and the computed data by quantum mechanical calculations. It is discovered for the first time that the ß-carboline at the C-8 position is bonded to the vasicine at the C-9 position. 1 exhibited moderate cytotoxic activity against HL-60 and A549 cell lines.


Asunto(s)
Alcaloides/química , Antineoplásicos Fitogénicos/farmacología , Carbolinas/farmacología , Peganum/química , Raíces de Plantas/química , Quinazolinas/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Carbolinas/química , Carbolinas/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Estructura Molecular , Extractos Vegetales/química
5.
Mikrochim Acta ; 186(4): 220, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30847576

RESUMEN

An electrochemical sensor that can resist biofouling even when operated in complex biological medium is developed for the determination of dopamine. It is based on the use of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) that is doped with the water insoluble ionic liquid (IL), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. A glassy carbon electrode modified with PEDOT/IL is shown to enable accurate determination of dopamine, as a model analyte in the presence of high concentrations of proteins, and resist biological fouling even in native serum. It exhibited a low limit of detection of 33 nM for the detection of dopamine, with a wide linear range from 0.2 to 328 µM (at 0.2 V vs. saturated calomel electrode). The PEDOT/IL modified glassy carbon electrode has a porous microstructure, high electrical conductivity and good stability. The sensor can be used to quantify dopamine in human urine samples with satisfying accuracy. Graphical abstract An antifouling electrochemical sensor capable of detecting target in complex biological samples was developed based on the use of a conducting polymer (PEDOT) that was doped with a water insoluble ionic liquid.

6.
Huan Jing Ke Xue ; 39(8): 3591-3600, 2018 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-29998665

RESUMEN

Reservoir/lake sediments are potential pollutant acceptors and sources of pollution. The Danjiangkou Reservoir, as the largest drinking water source in China, is the source water area for the Mid-route Project of the South-North Water Diversion. To illustrate the temporal and spatial changes in the environmental risks of both nutrients and heavy metals in the surface sediments of Danjiangkou Reservoir, the levels of pH, OM, TP, TN, and six kinds of metal elements during the period 2011-2016 were measured at five ecological sites. Canadian freshwater sediment quality guidelines for aquatic environments (from the CCME) were used to assess the potential ecological risks. The results showed that the contents of OM, TP, and TN in the surface sediments were 25.85, 0.57, and 1.34 g·kg-1, respectively, and those of Cr, Mn, Cu, Zn, Cd, and Pb were 57.96, 521.78, 13.91, 195.74, 0.37, and 12.92 mg·kg-1, respectively. The contents of both Zn and Cd were under the corresponding Ⅱ-level standards of soil environmental quality, but the contents of the other four heavy metals were lower than their corresponding I-level standards. After water diversion of the Mid-route Project, the OM, TN, Mn, and Zn contents increased, and the TP and other heavy metal contents displayed downward trends. Excluding the pH value, the distribution of measured nutrients and heavy metals in the surface sediments of the Danjiangkou Reservoir reached the extremely significant level (P<0.01). OM in the sediments was negatively correlated with TN and Pb, but had positive correlations with the other indicators measured. The results from the potential ecological risk assessment showed that:①Cd, Cu, and Pb had no harmful effects on organisms; ② OM had low ecological risk in most years; ③ the risk of TP was between zero and low ecological risk; and ④Cr, Zn, and TN had low ecological risk in most cases. The K and H sites had higher ecological risk for Cr, Zn, and TN, thus attention should be paid to those cases. These results illustrate the effects of human activities on nutrients and heavy metals in surface sediments.

7.
J Nat Prod ; 81(4): 749-757, 2018 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-29565129

RESUMEN

With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis. The separation of the enantiomers of 1-5 was accomplished by chiral-phase HPLC. The absolute configurations of the enantiomers of 1 and 5 were assigned by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The absolute configurations of the related compounds were determined via comparisons of their ECD data with those of the enantiomers of 1 and 5, respectively. Notably, compound 7, with a neo caged skeleton, is the first representative of a novel type of caged xanthone lacking a Δ8(8a) double bond. The isolated compounds exhibited significant cell growth inhibitory activities in vitro against human leukemic HL-60 and K562 cell lines, with GI50 values ranging from 0.2 to 8.8 µM. A preliminary structure-activity relationship is discussed.


Asunto(s)
Garcinia/química , Hojas de la Planta/química , Xantonas/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Bioensayo/métodos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Dicroismo Circular/métodos , Cristalografía por Rayos X/métodos , Células HL-60 , Humanos , Células K562 , Relación Estructura-Actividad , Xantonas/farmacología
8.
Fitoterapia ; 125: 155-160, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29355750

RESUMEN

Five pairs of new 2-oxoindole alkaloids, (±)-peganumalines A-E (1-5), and a new indole alkaloid, peganumaline F (6), along with two known analogues, were isolated from the seeds of Peganum harmala. Their structures and absolute configurations were elucidated through spectroscopic analyses and quantum chemistry calculations. Notably, (±)-peganumalines A (1) represent a pair of rare 2-oxoindole dimeric alkaloid enantiomer with the hitherto unknown carbon skeleton. All isolates were tested for antiproliferative and antibacterial activities.


Asunto(s)
Alcaloides Indólicos/química , Peganum/química , Semillas/química , Línea Celular Tumoral , Humanos , Alcaloides Indólicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular
9.
Bioorg Med Chem Lett ; 28(2): 103-106, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29229205

RESUMEN

Seventeen quinazoline alkaloids and derivatives, containing two pairs of new epimers, named as (S)- and (R)-1-(2-aminobenzyl)-3-hydroxypyrrolidin-2-one ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside (1, 2), (S)- and (R)-vasicinone ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside (3, 4), and a new enantiomer (12b), together with six known ones (5-8, 10, and 12a), and three pairs of known enantiomers (9, 11, and 13), were isolated from the ethanol extracts of the seeds of Peganum harmala L.. Their structures including the absolute configuration were elucidated by using 1D and 2D NMR, and ECD calculation approaches. The cytotoxic activities of all isolated compounds were evaluated. 11 showed moderate cytotoxicity against PC-3 cells with an IC50 value of 15.41 µM.


Asunto(s)
Alcaloides/farmacología , Antineoplásicos Fitogénicos/farmacología , Peganum/química , Quinazolinas/farmacología , Semillas/química , Alcaloides/química , Alcaloides/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Quinazolinas/química , Quinazolinas/aislamiento & purificación , Relación Estructura-Actividad
10.
Bioorg Med Chem Lett ; 27(10): 2161-2165, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28377060

RESUMEN

Three new (1-3) and one known (4) bioactive terpenoids were isolated from the seeds of Silybum marianum based on the investigation to get new NO inhibitors. Their structures were determined by extensive NMR (1D and 2D NMR) and MS spectroscopic data, and the absolute configurations were identified by experimental and calculated ECD spectra. The NO inhibitory activities in murine microglial BV-2 cells and interactions with iNOS protein by molecular docking were evaluated for all compounds. The results showed that these compounds had potent NO inhibitory effects.


Asunto(s)
Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico/metabolismo , Silybum marianum/química , Terpenos/química , Animales , Sitios de Unión , Línea Celular , Dicroismo Circular , Lipopolisacáridos/toxicidad , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Silybum marianum/metabolismo , Conformación Molecular , Simulación del Acoplamiento Molecular , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Extractos Vegetales/química , Estructura Terciaria de Proteína , Semillas/química , Semillas/metabolismo , Terpenos/aislamiento & purificación , Terpenos/farmacología
11.
Fitoterapia ; 111: 147-53, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27118321

RESUMEN

Three new phenylnaphthalene-type lignans, vitexnegheteroins E-G (1-3), and a new polyoxygenated ursane-type triterpene, vitexnegheteroin H (9), were isolated from the seeds of Vitex negundo var. heterophylla, together with ten known compounds. Their structures were established on the basis of extensive 1D and 2D NMR experiments, as well as their mass spectroscopic data. The absolute configurations of compounds 1 and 2 were determined by comparing their experimental ECD spectra with that calculated by the time-dependent density functional theory (TDDFT) method. The isolates were evaluated for their cytotoxicities against three human cancer cell lines, inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells, and antioxidant activities for ABTS radical scavenging.


Asunto(s)
Lignanos/química , Triterpenos/química , Vitex/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Humanos , Lignanos/aislamiento & purificación , Ratones , Microglía/efectos de los fármacos , Estructura Molecular , Óxido Nítrico/metabolismo , Triterpenos/aislamiento & purificación
12.
Biosens Bioelectron ; 58: 153-6, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24632460

RESUMEN

Significantly enhanced catalytic activity of a nanocomposite composed of conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) doped with graphene oxide (GO) was achieved through a simple electrochemical reduction process. The nanocomposite (PEDOT/GO) was electrodeposited on an electrode and followed by electrochemical reduction, and the obtained reduced nanocomposite (PEDOT/RGO) modified electrode exhibited lowered electrochemical impedance and excellent electrocatalytic activity towards the oxidation of dopamine. Based on the excellent catalytic property of PEDOT/RGO, an electrochemical sensor capable of sensitive and selective detection of DA was developed. The fabricated sensor can detect DA in a wide linear range from 0.1 to 175µM, with a detection limit of 39nM, and it is free from common interferences such as uric acid and ascorbic acid.


Asunto(s)
Técnicas Biosensibles/instrumentación , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Conductometría/instrumentación , Dopamina/análisis , Grafito/química , Nanocompuestos/química , Polímeros/química , Dopamina/química , Conductividad Eléctrica , Galvanoplastia/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Microelectrodos , Nanocompuestos/ultraestructura , Oxidación-Reducción , Óxidos/química
13.
Zhonghua Zhong Liu Za Zhi ; 28(12): 932-7, 2006 Dec.
Artículo en Chino | MEDLINE | ID: mdl-17533747

RESUMEN

OBJECTIVE: To evaluate the long-term effect of sodium glycididazole (CMNa) as a hypoxic radiosensitizer on the radiotherapy for nasopharyngeal carcinoma. METHODS: Between May 1999 and May 2002, 211 patients with pathologically confirmed nasopharyngeal carcinoma were randomized into group-A treated by radiotherapy plus CMNa or group-B by radiotherapy alone. The staging was determined according to 92' Fuzhou staging systerm. The type, procession and dosage of radiotherapy were identical in both groups. The early adverse effect grade was assessed based on the CTC2.0 criteria and the late adverse effects were evaluated according to the RTOG/EORTC criteria. The median follow-up time was 52 months. All the data was analyzed by the SPSS 13.0 software. Characteristics and adverse events of these patients were compared between the two groups using t-test and the Wilcoxin rank sum test. Time-to-event curves were estimated using the Kaplan-Meier method. The prognostic parameters were analyzed using univariate analysis and the Cox multivariate regression analysis. RESULTS: The clinical data of the two groups were comparable. The 3-year survival was 88.4% in group-A, while 75.2% in group-B, with a statistically significant difference between two groups (P = 0.010). Univariate analysis showed that the 3-year survival was statistically correlated with N-staging ((N0-1, 86.9%, N2-3 73.8%, P < 0.001), T-staging (T1-2 85.6%, T3-4 79.3%, P = 0.014), TNM staging (P = 0.039), and whether using CMNa or not during rediotherapy (Group-A 88.4%, Group-B 75.2%, P = 0.010). The 5-year recurrence-free survival, 5-year metastasis-free survival and 5-year overall survival were 75.8%, 74.9% and 77.7% in Group-A, while 63.0%, 63.0% and 62.4% in Group-B with a statistically significant difference between two groups (0.013, 0.022 and 0.010, respectively). If stratified in the subgroups, the overall survival of stage III - IV patients was statistically different between group A and B (P = 0.009), however, not of stage I - II patients (P = 0.502). Cox multivariate regression analysis showed that the independent prognostic parameters for survival were N-stage (RR = 3.288) , T-stage (RR = 2.147) and use of CMNa during rediotherapy (RR = 0.407). However, there was no statistically significant difference between two groups in acute or late adverse effects on nervous system or heart, which suggested that use of CMNa during radiotherapy would not aggravate the toxicity caused by radiotherapy. CONCLUSION: Sodium glycididazole is well tolerable effective as a hypoxic radiosensitizer, which can improve the efficacy of radiotherapy and the long-term result of nasopharyngeal carcinom a patients, especially for the stage III - IV patients.


Asunto(s)
Metronidazol/análogos & derivados , Neoplasias Nasofaríngeas/radioterapia , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Metronidazol/efectos adversos , Metronidazol/uso terapéutico , Persona de Mediana Edad , Análisis Multivariante , Neoplasias Nasofaríngeas/patología , Estadificación de Neoplasias/estadística & datos numéricos , Pronóstico , Modelos de Riesgos Proporcionales , Fármacos Sensibilizantes a Radiaciones/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Vómitos/inducido químicamente
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