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RNAs play crucial roles in various essential biological functions, including catalysis and gene regulation. Despite the widespread use of coarse-grained (CG) models/simulations to study RNA 3D structures and dynamics, their direct application is challenging due to the lack of atomic detail. Therefore, the reconstruction of full atomic structures is desirable. In this study, we introduced a straightforward method called ABC2A for reconstructing all-atom structures from RNA CG models. ABC2A utilizes diverse nucleotide fragments from known structures to assemble full atomic structures based on the CG atoms. The diversification of assembly fragments beyond standard A-form ones, commonly used in other programs, combined with a highly simplified structure refinement process, ensures that ABC2A achieves both high accuracy and rapid speed. Tests on a recent large dataset of 361 RNA experimental structures (30-692 nt) indicate that ABC2A can reconstruct full atomic structures from three-bead CG models with a mean RMSD of ~0.34 Å from experimental structures and an average runtime of ~0.5 s (maximum runtime < 2.5 s). Compared to the state-of-the-art Arena, ABC2A achieves a ~25% improvement in accuracy and is five times faster in speed.
Assuntos
Simulação de Dinâmica Molecular , RNA , RNA/química , NucleotídeosRESUMO
Panax ginseng, known as the "king of herbs", is a highly valued medicinal plant, and its medicinal parts include roots, stems, leaves, flowers, and fruits, among which the roots are the most commonly used. The main active components of this medicinal plant include triterpenoid saponins, polysaccharides, peptides, and volatile oils. The chemical components and active metabolites endow this herb with a variety of pharmacological effects, and thus this herb is used to treat various diseases and play healthcare roles. Currently, a wide range of preparations of P. ginseng have been officially registered and marketed, including tablets, oral liquids, and injections, which demonstrate good clinical efficacy in regulating immunity, adjuvant treatment of tumors, alleviating fatigue, delaying the aging process, improving glucose and lipid metabolism, treating cardiovascular diseases, and relieving inflammation and pain. The production process and quality standards of these drugs are of great significance to ensure their efficacy. According to the theory that Ginseng Radix et Rhizoma can greatly replenish original Qi, tonify the spleen and lung, promote fluid production to quench thirst, tranquilize mind and enrich the intelligence, this paper systematically summarized the clinical application progress of P. ginseng and rela-ted preparations on the market and prospected the further development of preparations from P. ginseng, providing a reference for further exploring the medicinal value and healthcare function of this herb. The above contents, as an important basis for the in-depth development of P. ginseng and related drugs, increase the possibilities for the application of P. ginseng.
Assuntos
Medicamentos de Ervas Chinesas , Panax , Panax/química , Humanos , Medicamentos de Ervas Chinesas/química , AnimaisRESUMO
Herein, by directly limiting the reaction space, an ingenious three-dimensional (3D) DNA walker (IDW) with high walking efficiency is developed for rapid and sensitive detection of miRNA. Compared with the traditional DNA walker, the IDW immobilized by the DNA tetrahedral nanostructure (DTN) brings stronger kinetic and thermodynamic favorability resulting from its improved local concentration and space confinement effect, accompanied by a quite faster reaction speed and much better walking efficiency. Once traces of target miRNA-21 react with the prelocked IDW, the IDW could be largely activated and walk on the interface of the electrode to trigger the cleavage of H2 with the assistance of Mg2+, resulting in the release of amounts of methylene blue (MB) labeled on H2 from the electrode surface and the obvious decrease of the electrode signal. Impressively, the IDW reveals a conversion efficiency as high as 9.33 × 108 in 30 min with a much fast reaction speed, which is at least five times beyond that of typical DNA walkers. Therefore, the IDW could address the inherent challenges of the traditional DNA walker easily: slow walking speed and low efficiency. Notably, the IDW as a DNA nanomachine was utilized to construct a sensitive sensing platform for rapid miRNA-21 detection with a limit of detection (LOD) of 19.8 aM and realize the highly sensitive assay of biomarker miRNA-21 in the total RNA lysates of cancer cell. The strategy thus helps in the design of a versatile nucleic acid conversion and signal amplification approach for practical applications in the areas of biosensing assay, DNA nanotechnology, and clinical diagnosis.
Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanoestruturas , MicroRNAs/genética , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , DNA/química , Nanoestruturas/química , Limite de DetecçãoRESUMO
Distant metastasis is the primary reason for treatment failure in patients with nasopharyngeal carcinoma (NPC). In this study, we investigated the effect of ulinastatin (UTI) on NPC metastasis and its underlying mechanism. Highly-metastatic NPC cell lines S18 and 58F were treated with UTI and the effect on cell proliferation, migration, and invasion were determined by MTS and Transwell assays. S18 cells with luciferase-expressing (S18-1C3) were injected into the left hind footpad of nude mice to establish a model of spontaneous metastasis from the footpad to popliteal lymph node (LN). The luciferase messenger RNA (mRNA) was measured by quantitative polymerase chain reaction (qPCR), and the metastasis inhibition rate was calculated. Key molecular members of the UTI-related uPA, uPAR, and JAT/STAT3 signaling pathways were detected by qPCR and immunoblotting. UTI suppressed the migration and infiltration of S18 and 5-8F cells and suppressed the metastasis of S18 cells in vivo without affecting cell proliferation. uPAR expression decreased from 24 to 48 h after UTI treatment. The antimetastatic effect of UTI is partly due to the suppression of uPA and uPAR. UTI partially suppresses NPC metastasis by downregulating the expression of uPA and uPAR.
Assuntos
Neoplasias Nasofaríngeas , Animais , Camundongos , Humanos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Camundongos Nus , Linhagem Celular Tumoral , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Luciferases , Movimento Celular , Invasividade Neoplásica , Metástase NeoplásicaRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can induce acute inflammatory response like acute lung inflammation (ALI) or acute respiratory distress syndrome, leading to severe progression and mortality. Therapeutics for treatment of SARS-CoV-2-triggered respiratory inflammation are urgent to be discovered. Our previous study shows that Salvianolic acid C potently inhibits SARS-CoV-2 infection. In this study, we investigated the antiviral effects of a Salvia miltiorrhiza compound, Danshensu, in vitro and in vivo, including the mechanism of S protein-mediated virus attachment and entry into target cells. In authentic and pseudo-typed virus assays in vitro, Danshensu displayed a potent antiviral activity against SARS-CoV-2 with EC50 of 0.97 µM, and potently inhibited the entry of SARS-CoV-2 S protein-pseudo-typed virus (SARS-CoV-2 S) into ACE2-overexpressed HEK-293T cells (IC50 = 0.31 µM) and Vero-E6 cell (IC50 = 4.97 µM). Mice received SARS-CoV-2 S via trachea to induce ALI, while the VSV-G treated mice served as controls. The mice were administered Danshensu (25, 50, 100 mg/kg, i.v., once) or Danshensu (25, 50, 100 mg·kg-1·d-1, oral administration, for 7 days) before SARS-CoV-2 S infection. We showed that SARS-CoV-2 S infection induced severe inflammatory cell infiltration, severely damaged lung tissue structure, highly expressed levels of inflammatory cytokines, and activated TLR4 and hyperphosphorylation of the NF-κB p65; the high expression of angiotensinogen (AGT) and low expression of ACE2 at the mRNA level in the lung tissue were also observed. Both oral and intravenous pretreatment with Danshensu dose-dependently alleviated the pathological alterations in mice infected with SARS-CoV-2 S. This study not only establishes a mouse model of pseudo-typed SARS-CoV-2 (SARS-CoV-2 S) induced ALI, but also demonstrates that Danshensu is a potential treatment for COVID-19 patients to inhibit the lung inflammatory response.
Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Humanos , Lactatos , Camundongos , Glicoproteína da Espícula de CoronavírusRESUMO
Kaixinsan powder (KXS), a classic prescription of traditional Chinese Medicine (TCM), is widely used in the treatment of depression, but its mechanism remains unclear. The network pharmacology method was used to constructe the "herb-component-target" network, and elucidated KXS potential mechanisms of action in the treatment of depression. Moreover, molecular docking was applied to valid the important interactions between the ingredients and the target protein. The "herb-component-target" network indicated that the ingredients of Girinimbin, Gomisin B and Asarone, and the protein targets of ESR, AR and NR3C1 mostly contribute to the antidepressant effect of KXS. KEGG pathway analysis highlighted the most significant pathways associated with depression treatment, including neuroactive ligand-receptor interaction pathway, serotonergic synapse pathway, PI3K-Akt signaling pathway and MAPK signaling pathway. Go enrichment analysis indicated that the mechanism of KXS in treating depression was involved in the biological process of GPCR signal transduction, hormone metabolism and nerve cell apoptosis. Moreover, molecular docking results showed that Polygalaxanthone III, Girinimbine and Pachymic acid performed greater binding ability with key antidepressant target 5-HTR. In conclusion, this study preliminarily revealed key active components in KXS, including Gomisin B, Asarone, Ginsenoside Rg1, Polygalaxanthone III and Pachymic acid, could interact with multiple targets (5-HTR, DR, ADRA, AR, ESR, NR3C1) and modulate the activation of multiple pathways (Neuroactive ligand -receptor interaction pathway, serotonergic synapse pathway, PI3K-Akt signaling pathway and MAPK signaling pathway).
Assuntos
Depressão , Fosfatidilinositol 3-Quinases , Pós , Simulação de Acoplamento Molecular , Depressão/tratamento farmacológico , Ligantes , Proteínas Proto-Oncogênicas c-akt , Antidepressivos/farmacologia , Antidepressivos/uso terapêuticoRESUMO
Two new furoquinoline alkaloids, named 1'-oxo-isoplatydesmine (1) and demethoxyacrophylline (2), as well as 11 known alkaloids (3-13) were isolated from the root bark of Dictamnus dasycarpus Turcz. The structures of 1 and 2 were established by detailed spectroscopic elucidation, such as 1 D & 2 D NMR and HRMS, etc. The unexpected autoracemization of 1 was discussed based on the stereochemistry of reported dihydrofuroquinolines. Compounds 3-5 exhibited moderate inhibitory activities against Bacillus subtilis, Candida albicans, and Pseudomonas aeruginosa with MICs 32-64 µg/ml, revealing the active principles of D. dasycarpus for treating skin diseases in its traditional usage.
Assuntos
Alcaloides , Anti-Infecciosos , Dictamnus , Anti-Infecciosos/farmacologia , Dictamnus/química , Estrutura Molecular , Casca de Planta/químicaRESUMO
Xuanfu Daizhe Decoction, first seen in Zhang Zhongjing's Treatise on Cold Damage Diseases, was composed of seven medicinal materials: Inulae Flos, Glycyrrhizae Radix, Ginseng Radix, Zingiberis Rhizoma Recens, Haematitum, Pinelliae Rhizoma and Jujubae Fructus. It was used to treat gastric fullness and hardness and belching due to the wrong treatment of typhoid fever and sweating. With detailed records and description in ancient medical books, Xuanfu Daizhe Decoction was widely adopted in clinical practice by physicians of later generations, which expanded its main therapeutic functions. By comprehensive collation of ancient and modern literature on Xuanfu Daizhe Decoction, this paper systematically explored the historical evolution of the prescription from the source, composition, dosage, processing, clinical application, function interpretation and decocting method. It was found that the composition and processing method of the prescription in the past dynasties were relatively consistent, and there was a gradual decrease in dosage in clinical application. In ancient times, Xuanfu Daizhe Decoction was mainly used to treat nausea, vomiting, hiccups, constipation, etc., while modern clinicians mainly used it for digestive diseases such as reflux esophagitis and gastritis. Through the analysis and textual research, the composition, dosage, processing, function evolution and decocting method of this prescription were determined, which provided reference for the research and development of compound preparations of Xuanfu Daizhe Decoction.
Assuntos
Medicamentos de Ervas Chinesas , Triterpenos , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Extratos Vegetais , RizomaRESUMO
Organophosphorus pesticides (OP) affect the crops and environments, and the reliable approach to the prediction of soil sorption of pesticides is required. In this respect, we proposed a simple Chemometrics approach, in which the Tchebichef image moment (TM) method was used to extract useful information from the greyscale images of molecular structures and the quantitative model was established by stepwise regression to predict the soil sorption of OPs. Different squared correlation coefficients including the leave-one-out cross-validation (LOO-CV) (Q2) that concerns the training set and the (R2test) which concerns the external independent test set are more than 0.96. This reflects that the established model has considerably high accuracy and reliability. Compared with the literature on the strategies of quantitative structure-property relationship (QSPR), the proposed method is more suitable, in which the established model shows a high predictive ability. Our study provides another effective approach to predict the soil sorption of OPs and also extends the innovative pathway of QSPR modelling.
Assuntos
Modelos Químicos , Compostos Organofosforados/química , Praguicidas/química , Poluentes do Solo/química , Adsorção , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Solo/químicaRESUMO
Indication and functions is an important key information in the research and development of the ancient classical formulas, which directly affects the clinical positioning of the compound formulas and their reasonable, effective and safe use after marke-ting. It is also the embodiment of the ultimate vitality of ancient classical formulas. Due to the particularity of ancient classical formulas, it is of great significance to accurately define and describe the functions and indications of classical formulas to exert their unqiue advantages. Based on the analysis of the provenances, classification of clinical indications, and functions of 100 prescriptions in the Catalogue of Ancient Classical Formulas(First Batch), this paper summarized the incompleteness, irregularity and inconsistency in the original text, the differences in terminology between ancient and modern times, and the evolution of the meanings of prescriptions in different dynasties. In addition, under the guidance of the general principle of textual researh on ancient classical formulas, which is to inherit the essence, make the past serve the present, link up the past and the present, and bulid consensus, this paper proposed the following ideas: respecting the original meanings and provenances of ancient classical formulas, taking full consideration of the development and evolution, serving the current clinical application and health needs, accurately linking up the ancient and modern terminologies, standardizing the expression of traditional Chinese medicine(TCM) terminology, highlighting the characteristics of TCM, attaching importance to the textual research principles and suggestions of post-marketing evidence-based and clinical positioning research, so as to determine the the functions and indications of the ancient classical formulas in a scientific, standardized and reasonable way and better guide the clinical application of the classical formulas.
Assuntos
Medicamentos de Ervas Chinesas , Óleos Voláteis , Medicina Tradicional Chinesa , PrescriçõesRESUMO
The determination of curcuminoids in mixtures is more difficult due to their similar chemical structures as well as serious interferences, thus the complex pretreatments of samples and the optimization of experimental conditions are often required. Here, owing to the mathematical separation of chemical signals by Tchebichef image moments, a simple and effective approach to the simultaneous quantitative analysis was proposed, and applied to the determination of the three curcuminoids in turmeric and curry based on their raw fluorescence 3D spectra. For the established linear models, the leave-one-out correlation coefficients (R loo-cv) were more than 0.9816 within the linear ranges, and the predictive correlation coefficients (R p) for the external independent samples were more than 0.9897. The intra- and inter-day precision (less than 6.82%, RSD), average spiked recovery (89.9% ~ 100.8%), LOD (less than 0.07 µg/mL) and LOQ (less than 0.23 µg/mL) suggest that the proposed approach is accurate and reliable. Compared with N-PLS and MCR-ALS methods, our method can obtain more satisfactory results. This study provides a convenient pathway for the rapid analysis of multi-target components with similar chemical structures in mixture of different substrates.
RESUMO
Chemicals pollution in the environment has attracted attention all over the world, and the toxicity prediction of chemical pollutants has become quite important. In this paper, we introduce a simple approach to predict the toxicity of some chemical components, in which the Tchebichef image moment (TM) method was employed to extract useful chemical information from the images of molecular structures to establish quantitative structure-activity relationship (QSAR) prediction models. The proposed approach was applied to predict the toxicity of anilines and phenols for the aquatic organisms of P. subcapitata and V. fischeri, in which the obtained TMs were defined as the independent variables, while the biological toxicity (pEC50) was regarded to be the dependent variable. Then, the predictive models were established by stepwise regression, respectively. The obtained squared correlation coefficients of leave-one-out cross-validation (Q2) for training sets and the predictive squared correlation coefficients (Rp2) for test sets of the two groups of data were higher than 0.79 and 0.75, respectively, which indicated that the obtained models possessed satisfactory accuracy and reliability. Compared with several reported methods, the proposed approach was more convenient and has a higher predictive capability. Our study provides another perspective in QSAR research.
Assuntos
Compostos de Anilina/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Modelos Teóricos , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Compostos de Anilina/química , Clorófitas/efeitos dos fármacos , Fenóis/química , Valor Preditivo dos Testes , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Poluentes Químicos da Água/químicaRESUMO
Although a large number of fluorescent probes have been developed, the simultaneous quantitative analysis of intracellular thiols is still difficult due to the spectral overlap and the complexity of the intracellular environment. In this study, a multi-signal fluorescent probe was employed for the simultaneous quantification of intracellular glutathione (GSH), cysteine (Cys) and homocysteine (Hcy). As the feature variables of the target components, the Tchebichef image moments (TMs) calculated from the grayscale images of the 3D fluorescence spectra were used to establish the quantitative linear models by stepwise regression. The intra-day and inter-day precisions of the proposed method were less than 5.6% and 8.7%, respectively. The recoveries ranged from 97.0% to 105.9%. In addition, the proposed approach was applied to the simultaneous quantitative determination of Cys, GSH and Hcy in the MCF-10A cell (a type of normal cell) and MDA-MB-231 cancer cell. The obtained results indicated that the concentrations of the three thiols in the cancer cell were higher than those in the normal cell. This study not only provides an effective approach for the quantification of multi-target bio-molecules in complicated intracellular environments, but also further extends the applications of multi-signal fluorescent probes, which will promote the design of new multi-signal fluorescent probes.
Assuntos
Benzotiazóis/química , Cumarínicos/química , Cisteína/análise , Corantes Fluorescentes/química , Glutationa/análise , Homocisteína/análise , Linhagem Celular Tumoral , Humanos , Análise dos Mínimos Quadrados , Limite de Detecção , Modelos Químicos , Análise de Componente Principal , Espectrometria de Fluorescência/métodosRESUMO
To extract the features in first-order or second-order signals, the two kinds of discrete Shmaliy moment (DSM) methods were proposed and applied to the quantitative analysis of multitarget compounds in complexes based on the UV-vis and high-performance liquid chromatography with pulsed amperometric detector (HPLC-PAD) spectra of samples for the first time. All the statistical parameters demonstrated that the obtained models were accurate and the established analytical methods were reliable, even in the presence of a different degree of overlapping signals as well as various interferences. Compared with Tchebichef moment (TM) and other classical methods such as multivariate curve resolution-alternating least-squares (MCR-ALS), partial least-squares (PLS) regression, and N-way partial least-squares (N-PLS), the proposed methods are more convenient and efficient, which not only provides another suitable tool for the quantitative analysis of multitarget components in complex samples but also extends the application of moment invariants in chemical signal analyses.
Assuntos
Bases de Dados de Compostos Químicos , Desenvolvimento de Medicamentos , Cromatografia Líquida de Alta Pressão , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Análise EspectralRESUMO
Circular dichroism (CD) spectroscopy is a widely used technique for the evaluation of protein secondary structures that has a significant impact for the understanding of molecular biology. However, the quantitative analysis of protein secondary structures based on CD spectra is still a hard work due to the serious overlap of the spectra corresponding to different structural motifs. Here, Tchebichef image moment (TM) approach is introduced for the first time, which can effectively extract the chemical features in CD spectra for the quantitative analysis of protein secondary structures. The proposed approach was applied to analyze reference set and the obtained results were evaluated by the strict statistical parameters such as correlation coefficient, cross-validation correlation coefficient and root mean squared error. Compared with several specialized prediction methods, TM approach provided satisfactory results, especially for turns and unordered structures. Our study indicates that TM approach can be regarded as a feasible tool for the analysis of the secondary structures of proteins based on CD spectra. An available TMs package is provided and can be used directly for secondary structures prediction.
Assuntos
Dicroísmo Circular , Estrutura Secundária de Proteína , Proteínas/química , Bases de Dados de ProteínasRESUMO
Ginsenoside-Rg1 (G-Rg1) is an agent isolated from Panax ginseng that exerts anti-fibrotic effects; however, the mechanism is still unclear. Herein, we investigated whether G-Rg1 administration can mitigate or reverse unilateral ureteral obstruction (UUO)-induced renal fibrosis by regulating the Klotho/transforming growth factor (TGF)-ß1/Smad signaling pathway in rats. Sprague-Dawley male rats were subjected to UUO, and rats in the treatment group were administered G-Rg1 or G-Rg1 plus Klotho short hairpin RNA interference (shRNA), while rats in the control and model groups were administered vehicle for 14 d. Epithelial-mesenchymal transition (EMT) biomarkers and Klotho/TGF-ß1 signaling molecules were examined by immunohistochemistry, quantitative real-time PCR and Western blotting. Immunohistochemistry showed that UUO induced increased pro-fibrotic TGF-ß1 expression, overexpression of the mesenchymal marker, α-smooth muscle actin (α-SMA), and suppression of the epithelial marker, E-cadherin. Moreover, Western blotting analysis indicated that UUO promoted TGF-ß1 and phosphorylated Smad3 (p-Smad3) expression (p<0.01), but blocked Klotho and Smad7 expression (p<0.01). After G-Rg1 administration, the UUO-induced TGF-ß1 and p-Smad3 expression was suppressed (p<0.01), whereas the reduced Klotho and Smad7 expression was reversed (p<0.05), followed by amelioration of the EMT process. Intriguingly, the G-Rg1 effects were largely abrogated by Klotho knockdown. Furthermore, Klotho expression was upregulated by G-Rg1 treatment at the mRNA and protein levels. Our results suggest that G-Rg1 may be beneficial for ameliorating renal fibrosis by targeting Klotho/TGF-ß1/Smad signaling in UUO rats.
Assuntos
Ginsenosídeos/farmacologia , Nefropatias/metabolismo , Substâncias Protetoras/farmacologia , Animais , Fibrose , Ginsenosídeos/uso terapêutico , Glucuronidase/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/tratamento farmacológico , Proteínas Klotho , Masculino , Substâncias Protetoras/uso terapêutico , Ratos Sprague-Dawley , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/complicaçõesRESUMO
Efficient separation and preconcentration of trace nanoparticulate silver (NAg) from large-volume environmental waters is a prerequisite for reliable analysis and therefore understanding the environmental processes of silver nanoparticles (AgNPs). Herein, we report the novel use of polyvinylidene fluoride (PVDF) filter membrane for disk-based solid phase extraction (SPE) of NAg in 1 L of water samples with the disk-based SPE system, which consists of a syringe pump and a syringe filter holder to embed the filter membrane. While the PVDF membrane can selectively adsorb NAg in the presence of Ag+, aqueous solution of 2% (m/v) FL-70 is found to efficiently elute NAg. Analysis of NAg is performed following optimization of filter membrane and elution conditions with an enrichment factor of 1000. Additionally, transmission electron microscopy (TEM), UV-vis spectroscopy, and size-exclusion chromatography coupled with ICP-MS (SEC-ICP-MS) analysis showed that the extraction gives rise to no change in NAg size or shape, making this method attractive for practical applications. Furthermore, feasibility of the protocol is verified by applying it to extract NAg in four real waters with recoveries of 62.2-80.2% at 0.056-0.58 µg/L spiked levels. This work will facilitate robust studies of trace NAg transformation and their hazard assessments in the environment.
Assuntos
Nanopartículas Metálicas , Polivinil , Poluentes Químicos da Água , Prata , Extração em Fase SólidaRESUMO
The present study was designed to simultaneously isolate the less polar ginsenosides from the flower buds of Panax ginseng (FBPG). Five ginsenosides, including a pair of new 20-methoxyl isomers, were extracted from FBPG and purified through a five-step integrated strategy, by combining ultrasonic extraction, Diaion Hp-20 macroporous resin column enrichment, solid phase extraction (SPE), reversed-phase high-performance liquid chromatography (RP-HPLC) analysis and preparation, and nuclear magnetic resonance (NMR) analysis. The quantification of the five ginsenosides was also discussed by a developed method with validations within acceptable limits. Ginsenoside Rg5 showed content of about 1% in FBPG. The results indicated that FBPG might have many different ginsenosides with diverse chemical structures, and the less polar ginsenosides were also important to the quality control and standardization of FBPG.
Assuntos
Flores/química , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Panax/química , Cromatografia Líquida de Alta Pressão , Isomerismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase SólidaRESUMO
In the daily life, we perceive the world around us by integrating multiple sensory cues (visual, auditory, olfactory, gustatory, tactile, vestibular and proprioceptive) to create a coherent, reliable representation that allows us to interact meaningfully with the environment. The integration of different sensory information is necessary for our perception, motor transformation, decision making, learning and memory. In the past decades, many interdisciplinary researchers have been attracted to the field of multisensory research, and tremendous advances have been made in this field. We review the researches on multisensory integration during self-motion perception in the past decades from the candidate areas, the integration principles and the neural correlation of the behaviors, with the intention to provide a comprehensive source for those interested in understanding the neural substrates for multisensory integration. Meanwhile, we also provide a prospect for the future research in this field.
Assuntos
Percepção de Movimento/fisiologia , Sensação/fisiologia , HumanosRESUMO
A simple and sensitive high-performance liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry (Q-trap-MS) method was developed and validated for the determination of veratramine, the major bioactive and neurotoxic component in Veratrum nigrum L. Veratramine and the internal standard (IS) were separated with a Waters Symmetry C18 column and eluted with a gradient mobile phase system containing acetonitrile and 0.1% aqueous formic acid. The analysis was performed by using positive electrospray ionization mode with multiple reaction monitoring (MRM). Transition ions of m/z 410.2 â 295.2 for veratramine and m/z 426.1 â 113.8 for the IS were monitored. The method was validated with a good linearity in the range of 1-1000 ng/mL and lower limit of quantification of 1 ng/mL. The precision (CV) of intra- and inter-day ranged from 3.92 to 7.29%, while the accuracy (bias) intra- and inter-day were between -4.78 and 1.65%. The recovery, stability and matrix effect were within the acceptable ranges. Five metabolites of veratramine, including four hydroxylated and one sulfated metabolites, were tentatively identified using predictive MRM-information dependent acquisition-enhanced product ion mode (predictive MRM-IDA-EPI). The developed method was successfully applied to the pharmacokinetic and metabolic study of veratramine in mice after oral administration of veratramine. Copyright © 2016 John Wiley & Sons, Ltd.