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1.
Org Biomol Chem ; 20(43): 8528-8532, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36278495

RESUMO

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.


Assuntos
Alcaloides , Peganum , Humanos , Peganum/química , Peganum/metabolismo , Morfolinos/análise , Morfolinos/metabolismo , Sementes , Estrutura Molecular , Alcaloides/farmacologia , Alcaloides/química , Carbolinas/farmacologia , Carbolinas/química
2.
Mikrochim Acta ; 186(4): 220, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30847576

RESUMO

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.

3.
Bioorg Med Chem Lett ; 28(2): 103-106, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29229205

RESUMO

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.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Peganum/química , Quinazolinas/farmacologia , Sementes/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Quinazolinas/química , Quinazolinas/isolamento & purificação , Relação Estrutura-Atividade
4.
J Nat Prod ; 81(4): 749-757, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29565129

RESUMO

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.


Assuntos
Garcinia/química , Folhas de Planta/química , Xantonas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Bioensaio/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular/métodos , Cristalografia por Raios X/métodos , Células HL-60 , Humanos , Células K562 , Relação Estrutura-Atividade , Xantonas/farmacologia
5.
Bioorg Med Chem Lett ; 27(10): 2161-2165, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28377060

RESUMO

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.


Assuntos
Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Silybum marianum/química , Terpenos/química , Animais , Sítios de Ligação , Linhagem Celular , Dicroísmo Circular , Lipopolissacarídeos/toxicidade , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Silybum marianum/metabolismo , Conformação Molecular , Simulação de Acoplamento Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Extratos Vegetais/química , Estrutura Terciária de Proteína , Sementes/química , Sementes/metabolismo , Terpenos/isolamento & purificação , Terpenos/farmacologia
6.
Phytochemistry ; 197: 113107, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35121215

RESUMO

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.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Peganum , Células A549 , Alcaloides/química , Antineoplásicos Fitogênicos/química , Células Hep G2 , Humanos , Peganum/química , Extratos Vegetais/química
7.
J Healthc Eng ; 2021: 5534607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126892

RESUMO

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.


Assuntos
COVID-19 , Infecção Hospitalar , Idoso , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Tomada de Decisões , Humanos , SARS-CoV-2
8.
Org Lett ; 22(19): 7522-7525, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-32936652

RESUMO

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.


Assuntos
Alcaloides/química , Antineoplásicos Fitogênicos/farmacologia , Carbolinas/farmacologia , Peganum/química , Raízes de Plantas/química , Quinazolinas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Carbolinas/química , Carbolinas/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Estrutura Molecular , Extratos Vegetais/química
9.
Huan Jing Ke Xue ; 39(8): 3591-3600, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998665

RESUMO

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.

10.
Fitoterapia ; 125: 155-160, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29355750

RESUMO

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.


Assuntos
Alcaloides Indólicos/química , Peganum/química , Sementes/química , Linhagem Celular Tumoral , Humanos , Alcaloides Indólicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular
11.
Zhonghua Zhong Liu Za Zhi ; 28(12): 932-7, 2006 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-17533747

RESUMO

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.


Assuntos
Metronidazol/análogos & derivados , Neoplasias Nasofaríngeas/radioterapia , Radiossensibilizantes/uso terapêutico , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Metronidazol/efeitos adversos , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias/estatística & dados numéricos , Prognóstico , Modelos de Riscos Proporcionais , Radiossensibilizantes/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Vômito/induzido quimicamente
12.
Fitoterapia ; 111: 147-53, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27118321

RESUMO

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.


Assuntos
Lignanas/química , Triterpenos/química , Vitex/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Humanos , Lignanas/isolamento & purificação , Camundongos , Microglia/efeitos dos fármacos , Estrutura Molecular , Óxido Nítrico/metabolismo , Triterpenos/isolamento & purificação
13.
Biosens Bioelectron ; 58: 153-6, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24632460

RESUMO

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.


Assuntos
Técnicas Biossensoriais/instrumentação , Compostos Bicíclicos Heterocíclicos com Pontes/química , Condutometria/instrumentação , Dopamina/análise , Grafite/química , Nanocompostos/química , Polímeros/química , Dopamina/química , Condutividade Elétrica , Galvanoplastia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Microeletrodos , Nanocompostos/ultraestrutura , Oxirredução , Óxidos/química
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