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1.
J Sep Sci ; 45(3): 739-751, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34865311

RESUMO

Trace amounts of components in traditional Chinese medicine are considered pharmacological active substances used for treating many serious diseases. However, purifying all the trace substances and making clear their structures are not easy. In this context, high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry based molecular networking was applied to investigate the chemical constituents of the roots of Aconitum kusnezoffii Reichb., which led to the identification of 33 nodes in different groups (N1-N33). Based on the excremental fragmentation pathway of known diterpenoid alkaloids (1-9) and comparisons of characteristic ions and characteristic loss of analogs in literature, the structures of unknown ions were deduced. This work lays a foundation for the evaluation of the clinical basis and mechanism of traditional Chinese medicine from the aspects of chemistry. In this paper, the method speculation of unknown natural products by means of molecular network method is expected to be applied in the discovery and change law of relevant active components in clinical pharmacology and the change of complex systems caused by trace active compounds.


Assuntos
Aconitum , Alcaloides , Diterpenos , Medicamentos de Ervas Chinesas , Aconitum/química , Alcaloides/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Diterpenos/análise , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem
2.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3066-3075, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467697

RESUMO

Lycii Cortex, the dry root bark of Lycium barbarum(Solanaceae), is rich in chemical compositions with unique structures, such as organic acids, lipids, alkaloids, cyclopeptides and other components, and plays an important role in traditional Chinese medicine. It has the effect of cooling blood and removing steam, clearing lung and reducing fire. It is mainly used in the treatment of hot flashes due to Yin deficiency, hectic fever with night sweat, cough, hemoptysis and internal heat and diabetes. Modern pharmacological studies have shown that the crude extract or monomer of Lycii Cortex has a variety of pharmacological activities, such as hypoglycemic, hypotensive, hypolipidemic, antibacterial, and antiviral effects. In this paper, the chemical constituents and pharmacological effects of Cortex Lycii were reviewed in order to further clarify its effective substances, promote the development of medical undertakings, and ensure the "Healthy China" plan.


Assuntos
Lycium , China , Hipoglicemiantes , Medicina Tradicional Chinesa , Casca de Planta
3.
Zhongguo Zhong Yao Za Zhi ; 46(5): 1155-1159, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787110

RESUMO

Chemical constituents of water extracts of Asplenium ruprechtii were investigated. Five compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC, and their structures were identified by various spectral analyses as aspleniumside G(1), trans-p-coumaric acid(2), trans-p-coumaric acid 4-O-ß-D-glucoside(3), cis-p-coumaric acid 4-O-ß-D-glucoside(4), and(E)-ferulic acid-4-O-ß-D-glucoside(5). Among them, compound 1 is a new 9,19-cycloartane glycoside.


Assuntos
Glicosídeos , Triterpenos , Cromatografia Líquida de Alta Pressão , Glucosídeos
4.
Chem Biodivers ; 17(12): e2000500, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078897

RESUMO

We characterized a new cycloartane glycoside, herein known as aspleniumside F (1), along with five known compounds as kaempferol-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-galacopyranoside (2), quercetin-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (3), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (4), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (5), and kaempferol-3-O-[(6-O-p-coumaroyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (6), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat Thromboangiitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HR-ESI-MS, analyses as well as through comparisons with previous reports, its chemical structure was determined as 3ß,24,30-tri-ß-D-glucopyranosyl-23,25-dihydroxycycloartane (= (23R,24R)-3ß,24-bis-(ß-D-glucopyranosyloxy)-23,25-dihydroxy-9ß-9,19-cyclolanostan-29-yl ß-D-glucopyranoside). According to the 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 were revealed as ß-D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC50 of 12.43, 6.78, 9.12, 6.94 and 4.85 µM revealed that compounds 2-6 had bioactivity.


Assuntos
Glicosídeos/química , Traqueófitas/química , Triterpenos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética
5.
Medicine (Baltimore) ; 103(8): e37236, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394495

RESUMO

To investigate the association of systemic inflammation index (SII) with psoriasis risk and psoriasis severity. This is a retrospective cohort study based on data from the National Health and Nutrition Examination Survey database from 2009 to 2014. The psoriasis information was obtained from the questionnaire data, and the SII was calculated as neutrophil × platelet/lymphocyte. We performed matching by controlling age and gender to reach a 1:2 ratio for better statistical power. Weighted logistic regression analysis, subgroup analysis, restricted cubic spline analysis, and threshold analysis were used to evaluate the association of SII with psoriasis risk. Besides, mediation analysis was conducted to assess the possible regulatory path. Finally, the receiver operating characteristic curve was plotted to analyze the predictive value of SII for psoriasis severity. The study involved 16,466 participants including 16,020 no-psoriasis participants and 446 psoriasis participants. After matching, psoriasis and non-psoriasis individuals were 446 and 892, respectively. SII was significantly higher in the psoriasis group than the non-psoriasis group (P < .05). Additionally, white blood cells and monocytes were significantly linked to psoriasis risk and SII scores (P < .05). Besides, SII elevation was an independent predictor for upregulated psoriasis risk (P < .05). There was a nonlinear relationship between SII and psoriasis risk (P nonlinear < .05), which was not mediated by white blood cells and monocytes. Unexpectedly, SII had no significance in predicting SII severity (P > .05). SII can independently predict psoriasis risk but has no impact on psoriasis severity. Further, SII serves as a potential and robust biomarker for identifying high-risk psoriasis individuals.


Assuntos
Plaquetas , Psoríase , Humanos , Inquéritos Nutricionais , Estudos Retrospectivos , Inflamação/epidemiologia , Psoríase/complicações , Psoríase/epidemiologia
6.
ACS Appl Mater Interfaces ; 13(1): 912-923, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356114

RESUMO

Microwave dielectric ceramics are vital for filters, dielectric resonators, and dielectric antennas in the 5G era. It was found that the (Cu1/3Nb2/3)4+ substitution can effectively adjust the TCF (temperature coefficient of resonant frequency) of Li2TiO3 and simultaneously increase its Q × f (Q and f denote the quality factor and the resonant frequency, respectively) value. Notably, excellent microwave dielectric properties (εr (permittivity) ≈ 18.3, Q × f ≈ 77,840 GHz, and TCF ≈ +9.8 ppm/°C) were achieved in the Li2Ti0.8(Cu1/3Nb2/3)0.2O3 (LTCN0.2) ceramic sintered at 1140 °C. Additionally, the sintering temperature of LTCN0.2 was reduced to 860 °C by the addition of 3 wt % H3BO3, exhibiting superior microwave dielectric properties (εr ≈ 21.0, Q × f ≈ 51,940 GHz, and TCF ≈ 1.4 ppm/°C) and being chemically compatible with silver. Moreover, LTCN0.2 + 3 wt % H3BO3 ceramics were designed as a patch antenna and a dielectric resonator antenna, both of which showed high simulated radiation efficiencies (88.4 and 93%) and gains (4.1 and 4.03 dBi) at the center frequencies (2.49 and 10.19 GHz). The LTCN0.2 + 3 wt % H3BO3 materials have promising future application for either 5G mobile communication devices and/or in low-temperature co-fired ceramic technology owing to their high Q, low sintering temperature, small density, and good temperature stability.

7.
Nanoscale ; 12(17): 9769-9775, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32324192

RESUMO

We propose a method for achieving THz ultra-broadband coherent absorption using the anti-reflection theory of metamaterials. The metamaterial absorber consists of a periodic array of electric ring resonators with a multilayered structure which form the desired refractive index dispersion and provide continuous anti-reflection over a wide frequency range. The destructive interference mechanism and resonance absorption of the absorber are determined by simulation analysis and numerical simulation. Simulation results show that the absorption bandwidth is almost 8.02 THz (absorption rate >90%) over the entire terahertz band (0.1 THz-10 THz). This design provides an effective and viable method for constructing broadband absorbers for stealth technology and the construction of enhanced transmittance devices.

8.
Vector Borne Zoonotic Dis ; 12(12): 1042-52, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23176446

RESUMO

Japanese encephalitis (JE) can infect many agriculturally important animals and humans, and has a high incidence in Asia. One of the natural hosts of the mosquito-borne JE virus (JEV) is domestic pigs, which act as amplifier hosts. Porcine infection results in fatal encephalitis, abortion, and stillbirth in pregnant sows, and hypospermia in boars. In this study, a rapid JEV detection method for swine and mosquitoes was developed based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) targeting the nucleocapsid (E) genes of JEV genotype I (lineage K94PO5), and genotype III (lineage SA14-14-2). Fifty-six swine blood samples and 20,000 mosquitoes were used to evaluate the method, compared to conventional RT-polymerase chain reaction (PCR) and real-time RT-PCR. RT-LAMP had detection limits of 2.57 and 2.34 copies/µL for JEV I and III, respectively. Assay sensitivity was similar to real-time RT-PCR, but was 10-fold higher than conventional RT-PCR. Assay specificity was high, showing no cross-reactivity to other flaviviruses. The results of virus isolation and identification of swine blood samples and mosquito samples were fully consistent with RT-LAMP. Finally, the JEV RT-LAMP assay was simpler and less time consuming than conventional RT-PCR or real-time RT-PCR, since the amplification step could be completed in a single tube within 50 min at 63°C. In conclusion, the newly-developed RT-LAMP assay is an accurate and convenient method for rapid and sensitive diagnosis of JEV in swine and mosquitoes, and may prove to be a practical molecular tool for surveillance and epidemiological investigations.


Assuntos
Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Encefalite Japonesa/veterinária , Insetos Vetores/virologia , Proteínas do Nucleocapsídeo/genética , Doenças dos Suínos/diagnóstico , Animais , Primers do DNA/genética , Reservatórios de Doenças , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/diagnóstico , Encefalite Japonesa/epidemiologia , Feminino , Humanos , Limite de Detecção , Gravidez , RNA Viral/sangue , Padrões de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Reversa/genética , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Fatores de Tempo , Zoonoses
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