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1.
Chem Rev ; 122(3): 3820-3878, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-34939420

RESUMO

With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies. This review summarizes the recent progress in the field of energy storage based on conventional as well as heat-resistant all-organic polymer materials with the focus on strategies to enhance the dielectric properties and energy storage performances. The key parameters of all-organic polymers, such as dielectric constant, dielectric loss, breakdown strength, energy density, and charge-discharge efficiency, have been thoroughly studied. In addition, the applications of computer-aided calculation including density functional theory, machine learning, and materials genome in rational design and performance prediction of polymer dielectrics are reviewed in detail. Based on a comprehensive understanding of recent developments, guidelines and prospects for the future development of all-organic polymer materials with dielectric and energy storage applications are proposed.

2.
J Chem Inf Model ; 63(24): 7669-7675, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38061777

RESUMO

Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics. A molecular graph generative model based on the invertible normalizing flow is trained on a data set containing 250k polymer molecular graphs (mostly generated by an RNN-based generative model) to learn the invertible transformations between latent distributions and molecular graph structures. When generating molecular graphs, a sample vector is drawn from the latent space, and then an adjacency tensor and node attribute matrix are generated through two invertible flows in two steps and assembled into a molecular graph. The model has the merits of exact likelihood training and an efficient one-shot generation process. The learned latent space is used to generate polymers with a high glass-transition temperature (Tg) and a wide band gap (Eg) for the application of high-temperature energy storage film capacitors. This work contributes to the efficient design of high-temperature polymer dielectrics by using deep generative models.


Assuntos
Polímeros , Temperatura , Modelos Moleculares , Probabilidade
3.
Zhongguo Zhong Yao Za Zhi ; 48(2): 443-454, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725234

RESUMO

To improve the quality control methods of Poria and develop and utilize its resources fully, alkaline extraction was used in this study to determine the yield and content of alkali-soluble polysaccharides of Poria. The alkali-soluble extracts of Poria were obtained according to the optimum extraction conditions on the basis of single-factor test, and 30 batches of samples were determined. The structure and chemical composition of the alkali-soluble extracts was characterized by high-performance gel permeation chromatography(HPGPC), Fourier transform infrared spectrometry(FT-IR), nuclear magnetic resonance(NMR) spectroscopy and high-performance liquid chromatography(HPLC) with 1-phenyl-3-methyl-5-pyrazolone(PMP-HPLC). The results showed that the content of the alkali-soluble extracts was in the range of 46.98%-73.86%. The main component was ß-(1→3)-glucan, and its molecular mass was about 1.093×10~5. Further, the content of alkali-soluble polysaccharides of Poria was measured by UV-Vis spectrophotometry and HPLC coupled with the evaporative light scattering detector(HPLC-ELSD), and 30 batches of samples were measured. The results indicated that the content of alkali-soluble polysaccharides determined by UV-Vis spectrophotometry was in the range of 73.70%-92.57%, and the content of samples from Hubei province was slightly higher than that from Yunnan province, Anhui province and Hunan province. The content of alkali-soluble polysaccharides determined by HPLC-ELSD was in the range of 51.42%-76.69%, and the samples from Hunan province had slightly higher content than that from the other three provinces. The content determined by UV-Vis spectrophotometry was higher than that by HPLC-ELSD. However, the content determined by HPLC-ELSD was close to that of alkali-soluble extract, which could accurately characterize the content of alkali-soluble polysaccharides in Poria, and the method was simple and repeatable. Therefore, it is recommended that the quantitative analysis method for alkali-soluble extract and alkali-soluble polysaccharides by HPLC-ELSD be used in the quality standards of Poria in Chinese Pharmacopeia.


Assuntos
Poria , Poria/química , Espectroscopia de Infravermelho com Transformada de Fourier , China , Polissacarídeos/química , Padrões de Referência , Cromatografia Líquida de Alta Pressão/métodos
4.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1632-1641, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005851

RESUMO

With the improvement of living standards and changes in working style, the prevalence of abnormal glucose and lipid metabolism in humans is increasing in modern society. Clinically, the related indicators are often improved by changing the lifestyle and/or taking hypoglycemic and lipid-lowering drugs, but there are no therapeutic drugs for disorders of glucose and lipid metabolism at present. Hepatitis C virus core protein binding protein 6(HCBP6) is a newly discovered target that can regulate triglyceride and cholesterol content according to level oscillations in the body, thereby regulating abnormal glucose and lipid metabolism. Relevant studies have shown that ginsenoside Rh_2 can significantly up-regulate the expression of HCBP6, but there are few studies on the effect of Chinese herbal medicines on HCBP6. Moreover, the three-dimensional structural information of HCBP6 has not been determined and the discovery of potential active components acting on HCBP6 is not rapidly advanced. Therefore, the total saponins of eight Chinese herbal medicines commonly used to regulate abnormal glucose and lipid metabolism were selected as the research objects to observe their effect on the expression of HCBP6. Then, the three-dimensional structure of HCBP6 was predicted, followed by molecular docking with saponins in eight Chinese herbal medicines to quickly find potential active components. The results showed that all total saponins tended to up-regulate HCBP6 mRNA and protein expression, where gypenosides showed the optimum effect on up-regulating HCBP6 mRNA and ginsenosides showed the optimum effect on up-regulating HCBP6 protein expression. Reliable protein structures were obtained after the prediction of protein structures using the Robetta website and the evaluation of the predicted structures by SAVES. The saponins from the website and literature were also collected and docked with the predicted protein, and the saponin components were found to have good binding activity to the HCBP6 protein. The results of the study are expected to provide ideas and methods for the discovery of new drugs from Chinese herbal medicines to regulate glucose and lipid metabolism.


Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Saponinas , Humanos , Glucose , Metabolismo dos Lipídeos , Simulação de Acoplamento Molecular , Medicamentos de Ervas Chinesas/farmacologia , Proteínas , RNA Mensageiro
5.
Eur J Neurol ; 29(6): 1643-1651, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35143095

RESUMO

BACKGROUND AND PURPOSE: DIRECT-MT showed that endovascular thrombectomy was noninferior to thrombectomy preceded by intravenous alteplase with regard to functional outcome in patients with acute ischemic stroke. In this post hoc analysis, we examined whether infarct size modified the effect of alteplase. METHODS: All patients with baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) grades were included. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Multivariate ordinal logistic regression analysis was used to calculate the adjusted common odds ratio (OR) for better functional outcome based on the mRS for thrombectomy alone versus combination therapy. An interaction term was entered to test for an interaction with baseline ASPECTS subgroups: 0-4 versus 5-7 versus 8-10. RESULTS: Of 649 patients, 323 (49.8%) were in the thrombectomy-alone group and 326 (50.2%) in the combination-therapy group. There was no significant treatment-by-trichotomized ASPECTS interaction with alteplase prior to endovascular treatment for the primary endpoint of ordinal mRS (p-value interaction term relative to ASPECTS 8-10: ASPECTS 0-4, p = 0.386; ASPECTS 5-7, p = 0.936). Adjusted common ORs for improvement in the 90-day mRS with thrombectomy alone compared with combination therapy were 1.99 (95% confidence interval = 0.72-5.46) for ASPECTS 0-4, 1.07 (0.62-1.86) for ASPECTS 5-7, and 1.03 (0.74-1.45) for ASPECTS 8-10. There was no significant difference in the safety outcomes between the two groups. CONCLUSIONS: Baseline infarct size may not modify the effect of alteplase prior to endovascular thrombectomy with regard to favorable functional outcomes and adverse events.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Humanos , Infarto/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
6.
Zhongguo Zhong Yao Za Zhi ; 47(4): 980-987, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35285198

RESUMO

The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-ß-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP value>1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Coptis chinensis , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Tecnologia
7.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2912-2922, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34467681

RESUMO

The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 µm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(R > 1.5) and showed good linearity(r > 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Basidiomycota , Cromatografia Líquida de Alta Pressão , Guanosina
8.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1339-1344, 2021 Mar.
Artigo em Zh | MEDLINE | ID: mdl-33787130

RESUMO

Chrysanthemum is widely used as a type of edible flower and also considered as the important materials of many beverages in China. Due to the occurrence of diseases and pests, and the lack of regulations for species, frequency, dose of pesticides in Chrysanthemum, pesticides have become one of the main pollutants in Chrysanthemum. The pesticide residues in Chrysanthemum were detected frequently and worth noting. This paper focused on the types of pesticides, pesticide residue detection techniques, and risk assessment methods for Chrysanthemums on the basis of relevant literatures. The pesticide residues of traditional Chinese medicine are mainly organochlorines, organophosphorus and pyrethroids, and the detection techniques include gas chromatography(GC), liquid chromatography(LC) or both combined with mass spectrometry(MS). With the increasing use of traditional Chinese medicine, Chrysanthemum is widely circulated in the market. Therefore, it is important to understand the current situation of pesticide residues in different varieties of Chrysanthemum, so as to provide theoretical reference for the control of quality and safety of Chrysanthemum and the formulation of the maximum residue limit.


Assuntos
Chrysanthemum , Resíduos de Praguicidas , China , Cromatografia Líquida , Chrysanthemum/genética , Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise
9.
BMC Genomics ; 21(1): 560, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32799794

RESUMO

BACKGROUND: High temperatures, particularly at night, decrease rice yield and quality. As high nighttime temperatures (HNTs) become increasingly frequent due to climate change, it is imperative to develop rice crops that tolerate HNTs. DNA methylation may represent a potential avenue for HNT-tolerant rice strain development, as this mechanism regulates gene activity and cellular phenotype in response to adverse environmental conditions without changing the nucleotide sequence. RESULTS: After HNT exposure, the methylation patterns of cytosines in the CHH context differed noticeably between two coisogenic rice strains with significantly different levels in heat tolerance. Methylation differences between strains were primarily observed on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, the regions 358-359 bp and 2-60 bp downstream of two basal transcriptional factors (TFIID subunit 11 and mediator of RNA polymerase II transcription subunit 31, respectively) were fully demethylated in the heat-tolerant strain after HNT exposure. In the heat-tolerant strain, HNTs reversed the methylation patterns of successive cytosines in the promoter regions of various genes involved in abscisic acid (ABA)-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain gene PPR (LOC_Os07g28900) and the homeobox domain gene homeobox (LOC_Os01g19694). Indeed, PRR expression was inhibited in heat-sensitive rice strains, and the methylation rates of the cytosines in the promoter region of PRR were greater in heat-sensitive strains as compared to heat-tolerant strains. CONCLUSIONS: After HNT exposure, cytosines in the CHH context were more likely than cytosines in other contexts to be methylated differently between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes associated with ABA-related oxidation and ROS scavenging improved heat tolerance in rice. Our results help to clarify the molecular mechanisms underlying rice heat tolerance.


Assuntos
Oryza , Termotolerância , Citosina , Metilação de DNA , Regulação da Expressão Gênica de Plantas , Oryza/genética , Regiões Promotoras Genéticas
10.
J Virol ; 93(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30333168

RESUMO

Type I interferon (IFN) inhibits viruses by inducing the expression of antiviral proteins. The IFN-induced myxovirus resistance B (MxB) protein has been reported to inhibit a limited number of viruses, including HIV-1 and herpesviruses, but its antiviral coverage remains to be explored further. Here we show that MxB interferes with RNA replication of hepatitis C virus (HCV) and significantly inhibits viral replication in a cyclophilin A (CypA)-dependent manner. Our data further show that MxB interacts with the HCV protein NS5A, thereby impairing NS5A interaction with CypA and NS5A localization to the endoplasmic reticulum, two events essential for HCV RNA replication. Interestingly, we found that MxB significantly inhibits two additional CypA-dependent viruses of the Flaviviridae family, namely, Japanese encephalitis virus and dengue virus, suggesting a potential link between virus dependence on CypA and virus susceptibility to MxB inhibition. Collectively, these data have identified MxB as a key factor behind IFN-mediated suppression of HCV infection, and they suggest that other CypA-dependent viruses may also be subjected to MxB restriction.IMPORTANCE Viruses of the Flaviviridae family cause major illness and death around the world and thus pose a great threat to human health. Here we show that IFN-inducible MxB restricts several members of the Flaviviridae, including HCV, Japanese encephalitis virus, and dengue virus. This finding not only suggests an active role of MxB in combating these major pathogenic human viruses but also significantly expands the antiviral spectrum of MxB. Our study further strengthens the link between virus dependence on CypA and susceptibility to MxB restriction and also suggests that MxB may employ a common mechanism to inhibit different viruses. Elucidating the antiviral functions of MxB advances our understanding of IFN-mediated host antiviral defense and may open new avenues to the development of novel antiviral therapeutics.


Assuntos
Ciclofilina A/farmacologia , Hepacivirus/fisiologia , Interferons/farmacologia , Proteínas de Resistência a Myxovirus/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Chlorocebus aethiops , Ciclosporina/farmacologia , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Hepacivirus/efeitos dos fármacos , Humanos , Proteínas de Resistência a Myxovirus/genética , Ligação Proteica/efeitos dos fármacos , Células Vero
11.
Neuroradiology ; 62(7): 867-876, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32242265

RESUMO

PURPOSE: Data on posterior circulation tandem occlusions in acute ischemic stroke are scarce: recognition may be challenging and little is known about optimal treatment strategy. We report our endovascular treatment strategy for posterior circulation tandem occlusion. METHODS: Consecutive patients with posterior circulation tandem occlusions in our centre were enrolled retrospectively. The preferred strategy was "distal-to-proximal" strategy, which means opening the distal occlusion first followed by treatment of the proximal pathology. The imaging characteristics, treatment strategy, clinical outcomes, and complications of patients with posterior circulation tandem occlusions were analyzed. RESULTS: In total, 21 patients with posterior circulation tandem occlusions were enrolled in the study, which accounted for 23.6% of patients with posterior circulation stroke in our centre. The mean age was 60 years (range 32 to 80), and median pre-procedure NIHSS score was 28 (interquartile range: 13-31). Eighteen patients (85.7%) had vertebrobasilar artery tandem occlusions and 3 (14.3%) had basilar artery to basilar artery tandem occlusions. All distal occlusions were successfully recanalized (modified TICI 2b/3). Two (9.5%) of the proximal lesions were not treated. A total of 57.1% of the patients had stents implanted on the proximal occlusions. The rate of mRS 0-3 at 3 months was 57.1% and the mortality rate was 19.0%. CONCLUSION: In patients with acute ischaemic stroke caused by posterior circulation tandem occlusions, we favor "distal-to-proximal" strategy based on the positive results in this small series. Nevertheless, a more extensive study is required to explore the optimal treatment strategy further.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Neuroimagem/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1717-1725, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489054

RESUMO

The effects of the growing periods, processing methods, nutritive organs and cut parts of the herbs on the quality of Andrographis Herba have been studied, which could provide scientific basis for producing high-quality crude materials of Andrographis Herba. A quantitative analysis of multi-components by single-marker(QAMS) method was used to simultaneously determine 4 diterpene lactones of andrographolide(AD), neoandrographolide(NAD), 14-deoxyandrographolide(14-DAD), and dehydroandrographolide(DHAD) in 78 batches of Andrographis Herba samples. Visual analysis, clustering analysis and partial least squares discrimination analysis(PLS-DA) were used for data processing and mining. The growing periods of Andrographis Herba were divide into the rapid growing stage(Ⅰ), the luxuriant foliage stage(Ⅱ), the bud stage(Ⅲ), the flower stage(Ⅳ), the fruiting stage(Ⅴ) and the later fruiting stage(Ⅵ), six ones in total. The results showed that the total contents of 4 diterpene lactones(TC) kept almost constant in growing periods of Ⅰ-Ⅲ, began to fall off in growing period Ⅳ, decreased rapidly in growing period Ⅴ and reduced to minimum in growing period Ⅵ. Therefore, the best harvesting period for Andrographis Herba was the bud stage. For the processing methods, none significant difference occurred for TC between drying by the sun and drying in the shade. However, in comparison of the samples dried by the sun, the samples dried in the shade exhibited lower content of AD, nonetheless, the higher contents of DHAD and NAD, indicating that the process of drying in the shade may lead to the decomposition and transformation of AD. Therefore, when the weather conditions permitted, the method drying by the sun should be used. The distributions of AD, DHAD and TC in the different cut parts and nutritive organs were determined as follows: upper cut parts > middle cut parts ≈ entire herbs > lower cut parts, leaves > entire herbs > stems. Furthermore, the contents of 4 diterpene lactones in leaves and herbs were much higher than those in stems. Therefore, it was suggested that the upper and middle cut parts of the herbs or the parts containing leaves should be preferred for harvesting to ensure the proportion of the leaves in Andrographis Herba.


Assuntos
Andrographis , Diterpenos , Lactonas , Folhas de Planta
13.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2091-2102, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-32495558

RESUMO

Taking Lonicerae Japonicae Flos as an example, the method of "expert consensus of different regions" was used to screen the representative samples and evaluate their commodity grades. The correlation analysis, hierarchical cluster analysis and partial least squares discriminant analysis(PLS-DA) of "commodity grade-appearance characteristic-component content" were carried out to reveal the scientificity of traditional commodity grade of Chinese medicinal material. By referring to the existing literature and the grade investigation from the sample collection regions, 78 "initial grade" samples were screened out from 118 collected samples. Authoritative experts from four regions(n=4) including Linyi(Shangdong province), Bozhou(Anhui province), Anguo(Hebei province) and Beijing were organized to evaluate their commodity grades, separately. Based on the grade consistency rate(R_i≥70%), 69 "local grade" samples were screened out from the "initial grade" samples. Based on the average grade consistency rate ■ "authoritative grade" samples were screened out from the "local grade" samples, including15 first-grade samples, 9 second-grade samples, 11 third-grade samples and 17 fourth-grade samples. For these "authoritative grade" samples, the main appea-rance characteristics were quantified and the contents of 13 components were determined by ultra performance liquid chromatography(UPLC). Furthermore, the total contents of 6 phenolic acids, 4 flavonoids and 3 iridoids were calculated, respectively. The results of correlation analysis showed that 4 appearance characteristics indices were correlated with the commodity grades: color, rate of yellow bars(including blooming flowers), rate of black heads(including black bars), and rate of stems and leaves(including bud debris). Five component content indices were correlated with the commodity grades: chlorogenic acid, isochlorogenic acid C, sweroside, loganin and the total contents of six phenolic acids. Furthermore, chlorogenic acid, loganin and the total contents of six phenolic acids showed significantly negative correlation with the main appearance characteristics, indicating that the appearance characteristics of Lonicerae Japonicae Flos can reflect its internal quality, and these 3 indices can be used as quality markers(Q-markers). The results of hierarchical cluster analysis showed that the samples of four grades were classified into four categories, and the samples with the same grades and the same categories accounted for 80.8% of the total samples, while the samples with the different grades were obviously classified into different categories. The results of PLS-DA analysis showed that the samples of different grades showed obvious intragroup aggregation and intergroup dispersion. The above results indicated that it was feasible to evaluate the traditional commodity grade of Lonicerae Japonicae Flos by the method of "expert consensus of different regions". For the evaluation of traditional commodity grade of Chinese medicinal material, the samples should be representative, expert conclusions should have enough consensuses, and grade determination should be authoritative. As the crystallization of clinical experience, traditional commodity grade can scientifically reflect the internal quality of Chinese medicinal material.


Assuntos
Medicamentos de Ervas Chinesas , Lonicera , Cromatografia Líquida de Alta Pressão , Flores , Controle de Qualidade
14.
PLoS Pathog ; 13(9): e1006625, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28938017

RESUMO

Enterovirus 71 (EV71) is the major causative agent of hand, foot and mouth disease (HFMD) in children, causing severe clinical outcomes and even death. Here, we report an important role of the highly conserved alanine residue at position 107 in the capsid protein VP1 (VP1A107) in the efficient replication of EV71. Substitutional mutations of VP1A107 significantly diminish viral growth kinetics without significant effect on viral entry, expression of viral genes and viral production. The results of mechanistic studies reveal that VP1A107 regulates the efficient cleavage of the VP0 precursor during EV71 assembly, which is required, in the next round of infection, for the transformation of the mature virion (160S) into an intermediate or A-particle (135S), a key step of virus uncoating. Furthermore, the results of molecular dynamic simulations and hydrogen-bond networks analysis of VP1A107 suggest that flexibility of the VP1 BC loop or the region surrounding the VP1107 residue directly correlates with viral infectivity. It is possible that sufficient flexibility of the region surrounding the VP1107 residue favors VP0 conformational change that is required for the efficient cleavage of VP0 as well as subsequent viral uncoating and viral replication. Taken together, our data reveal the structural role of the highly conserved VP1A107 in regulating EV71 maturation. Characterization of this novel determinant of EV71 virulence would promote the study on pathogenesis of Enteroviruses.


Assuntos
Enterovirus Humano A/fisiologia , Infecções por Enterovirus/virologia , Células Vero/virologia , Replicação Viral/genética , Aminoácidos/genética , Animais , Proteínas do Capsídeo/metabolismo , Chlorocebus aethiops , Mutação de Sentido Incorreto/genética , Internalização do Vírus
15.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2078-2083, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-31355564

RESUMO

The traditional Chinese medicine standard decoction is prepared on the basis of the theory of traditional Chinese medicine and clinical application. With reference to the modern extraction method,the single decoction of traditional Chinese medicine is prepared by the standardized process,and the establishment of its quality standards is conducive to standardizing clinical medication. This research is to set an evaluation standard for the quality of salt-processed Psoraleae Fructus standard decoction. Twelve batches of salt-processed Psoraleae Fructus standard decoctions were prepared. The contents of psoralen and isopsoralen were determined,the transfer and extract rates were calculated,and the pH value was measured; HPLC fingerprint method was established for analysis. The results of the 12 batches of samples revealed that the transfer rates of psoralen and isopsoralen were 17. 10%-26. 40%,14. 70%-22. 70%,respectively; the extract rate was between 14. 7%-27. 0%,and the pH value was between 5. 4-6. 9. Moreover,7 common chromatographic peaks were determined based on fingerprint by using similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( 2012 A).The similarities of the 12 batches of samples were analyzed and compared,and the results showed that the similarities were all higher than0. 9. In this study,the preparation method for salt-processed Psoraleae Fructus decoction was standard,with high similarities in fingerprint. This study build a convenient and reliable method of comprehensive quality evaluation,with a high precision,stability and repeatability,which can provide a reference for the quality control of salt-processed Psoraleae Fructus dispensing granules.


Assuntos
Medicamentos de Ervas Chinesas/análise , Frutas/química , Psoralea/química , Controle de Qualidade , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa , Compostos Fitoquímicos/análise
16.
Zhongguo Zhong Yao Za Zhi ; 44(4): 730-739, 2019 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30989886

RESUMO

To solve the problems of the poor resolution of chromatographic separation,the weak durability of the relative correction factors,and the low accuracy of content determination results in the quantitative analysis of multi-components by single-marker( QAMS) method with andrographolide as the internal reference substance in the existing research of Andrographis Herba,a new QAMS method using dehydroandrographolide as the internal reference substance was established for the first time in this study. This new method can be used to simultaneously determine four diterpene lactones,including andrographolide( A),neoandrographolide( B),14-deoxyandrographolide( C),and dehydroandrographolide( S) through the optimization of chromatographic conditions and systematic investigation of methodology. At the present HPLC chromatographic conditions,four components could be well separated( R > 1. 5),and the methodology validations could satisfy the requirement of quantitative analysis. The relative correction factors( RCFs) of fA/S,fB/S,fC/S were determined as 0. 65,0. 54,0. 78,respectively. The relative standard deviations( RSDs) of their RCFs ranged between 1. 3%-5. 1%,0. 25%-0. 33%,0. 070%-0. 15%,0. 070%-0. 22%,respectively with three brands of HPLC instruments,five brands of C18 column,different flow rates( 0. 9,1. 0,1. 1 m L·min~(-1)),and different column temperatures( 25,30,35 ℃),indicating good durability of the RCFs. The relative retention value( RRV) method was used to locate the chromatographic peak of the components to be determined.The RRVs of rA/S,rB/S,and rC/Swere 0. 44,0. 86,0. 97,respectively. The RSDs of the RRVs ranged between 0. 030%-1. 6% with different HPLC instruments and columns,showing accurate peak location. The present QAMS method and the external standard method( ESM)were both used to determine the contents of four diterpene lactones from Andrographis Herba( 6 batches of medicinal materials and 18 batches of cut crude drugs). The relative errors of the determined content results between two methods were less than 2. 0%. It demonstrated that there was no significant difference in content results between these two methods,indicating good accuracy of the present QAMS method. Therefore,in this study,an accurate and highly durable QAMS method using dehydroandrographolide as the internal reference substance was established for simultaneous determination of four diterpene lactones. This method could be used to effectively control the quality of Andrographis Herba and provide technical basis for the formulation of traditional Chinese medicine industry standard and improvement of the Chinese Pharmacopoeia standard of Andrographis Herba.


Assuntos
Andrographis , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Diterpenos , Controle de Qualidade
17.
Zhongguo Zhong Yao Za Zhi ; 41(15): 2843-2854, 2016 Aug.
Artigo em Zh | MEDLINE | ID: mdl-28914027

RESUMO

Through a series of methodology investigations, we established a new method for simultaneous analysis of epimedins A, B, C, icariin and baohuoside I in Epimedii Folium by using high performance liquid chromatography (HPLC). Meanwhile, using Icariin as an internal reference substance to establish the relative correct factors and relative retention values of Epimedins A, B, C and Baohuoside I to Icariin, then using the quantitative analysis of multi-components by single-marker (QAMS) model, the five analytes can be quantitatively determined in Epimedii Folium and its processed products as well as Kanggu Zengsheng capsule only by measuring the content of icariin in the corresponding samples. All these analysis are completed in the same chromatorgraphic conditions. This paper played the part of demonstration role in the popularization and application of QAMS method established in a single herb to the proprietary Chinese medicines containing this herb.


Assuntos
Medicamentos de Ervas Chinesas/química , Epimedium/química , Flavonoides/química , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/química
18.
Zhongguo Zhong Yao Za Zhi ; 41(18): 3389-3399, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-28925122

RESUMO

Using reversed-phase high performance liquid chromatography, nine ginsenosides were simultaneously separated on an UltimateC18 column with high-resolution and high purity of each chromatographic peak. Adopting the QAMS quality evaluation model for traditional Chinese medicines, ginsenoside Rb1 was used as the internal reference substance, and the relative correction factors (RCFs) and the relative retention values (RTRs) of ginsenosides Rg1, Re, Rf, Rb1, Rc, Rb2, Rb3, Rd and 20 (S)-ginsenoside Rg3 to ginsenoside Rb1 were calculated individually. Through a series of methodology evaluations, and positioned by the red ginseng reference chromatograph and RTVs, nine ginsenosides in red ginseng were simultaneously assayed only by quantitative determined ginsenoside Rb1.


Assuntos
Ginsenosídeos/análise , Panax/química , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes
19.
Zhongguo Zhong Yao Za Zhi ; 41(14): 2660-2668, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-28905603

RESUMO

This paper aims to investigate the correlation between the antioxidant activity of Prunella vulgaris and its total phenolic acids content by measuring the antioxidant activity of different sources and different organs of P. vulgaris and the total contents of protocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid in these samples. Using the 50% methanol extract of P. vulgaris samples as the research object, DPPH method and HPLC method were used respectively to determine the antioxidant activities and the total contents of the above-mentioned five analytes in P. vulgaris samples. 0.5 mL of 50% methanol extract of P. vulgaris reacts with 0.1 mmol•L⁻¹ DPPH ethanol solution for 60 min, then the absorbance of the reaction solution was measured at 517 nm, scavenging rate and IC50 values were calculated by the absorbance and the sample concentration for evaluating the antioxidant activity. HPLC analysis was made on a C18 Epic column, with acetonitrile-0.1% formic acid aqueous solution as mobile phase (gradient elution), and the detection wavelength was set at 280 nm. The correlation between the antioxidant capacity of different habitats and different organs of P. vulgaris and the total contents of five kinds of phenolic acids was analyzed by partial least squares method. The reaction dose-response range of 50% methanol extract of P. vulgaris with 0.1 mmol•L⁻¹ DPPH ethanol solution was 0.300-1.65 g•L⁻¹. When the quantities of potocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid were respectively in 0.007 84-0.980, 0.011 5-1.44, 0.008 64-1.08, 0.080 0-1.00 and 0.079 8-0.998 µg range, their quantities were in good linear relationship with the corresponding peak areas. The average recovery of 5 components were 97.76%, 96.88%, 100.3%, 102.1%, 104.5%, with RSD of 1.8%, 1.6%, 1.7%, 1.6% and 1.7%, respectively. In a certain range of crude drug quantity, the antioxidant activity of each organ of P. vulgaris and total phenolic acids content inside has a good linear correlation. Therefore, in certain quality range of crude drug, DPPH bioassay combined with HPLC content determination can be used for the quality control of P. vulgaris, as is a new method for the quality control of P. vulgaris.


Assuntos
Antioxidantes/análise , Medicamentos de Ervas Chinesas/normas , Hidroxibenzoatos/análise , Prunella/química , Bioensaio , Cromatografia Líquida de Alta Pressão , Extratos Vegetais
20.
Biomed Chromatogr ; 29(7): 1112-23, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25545174

RESUMO

Radix Scutellariae (RS) is a herbal medicine with various pharmacological activities to treat inflammation, respiratory and gastrointestinal infections, etc. In this study, a rapid, sensitive and selective UPLC-ESI-MS/MS method was developed for simultaneous determination of 10 flavonoids - scutellarin, scutellarein, chrysin, wogonin, baicalein, apigenin, wogonoside, oroxylin A-7-O-glucuronide, oroxylin A and baicalin - from RS aqueous extracts in rat plasma with propyl paraben as internal standard (IS). Chromatographic separation was achieved on a C18 column using gradient elution with the mobile phase consisting of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. The detection was performed in multiple reaction monitoring mode using electrospray ionization in negative mode. The validated method showed good linearity over a wide concentration range (r >0.9935). The intra- and interday assay variabilities were <9.5% and <12.4% for all analytes, respectively. The extraction recovery ranged from 71.2 to 89.7% for each analyte and IS. This method was successfully applied to pharmacokinetic comparision after oral administration of crude and wine-processed RS aqueous extracts. There were significant differences in some pharmacokinetic parameters of most analytes between crude and wine-processed RS. This suggested that wine-processing exerted effects absorption of most flavonoids.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Flavonoides/sangue , Scutellaria baicalensis/química , Vinho/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas/farmacocinética , Flavonoides/química , Flavonoides/farmacocinética , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
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