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1.
J Nat Prod ; 86(10): 2326-2332, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37748016

RESUMEN

3'-O-ß-Glucosyl-4',5'-didehydro-5'-deoxyadenosine 13 is identified as a natural product of Streptomyces calvus and Streptomyces virens. It is also generated in vitro by direct ß-glucosylation of 4',5'-didehydro-5'-deoxyadenosine 12 with the enzyme NucGT. The intact incorporation of oxygen-18 and deuterium isotopes from (±)[1-18O,1-2H2]-glycerol 14 into C-5' of nucleocidin 1 and its related metabolites precludes 3'-O-ß-glucosyl-4',5'-didehydro-5'-deoxyadenosine 13 as a biosynthetic precursor to nucleocidin 1.


Asunto(s)
Productos Biológicos
2.
Org Biomol Chem ; 19(46): 10081-10084, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34779476

RESUMEN

Genome homology and the presence of a putative biosynthetic gene cluster identified Streptomyces aureorectus DSM 41692 and Streptomyces virens DSM 41465 as candidate producers of the antibiotic nucleocidin 1. Indeed when these bacterial strains were cultured in a medium supplemented with fluoride (4 mM) they each produced nucleocidin 1 and the previously identified 4'-fluoro-3'-O-ß-glucosylated adenosine 2 and its sulfamylated derivative 3. In both of these cases 4'-fluoroadenosine 9 is also identified as a natural product although it has never been observed during fermentations of Streptomyces calvus, the original source of nucleocidin 1. The identity of 4'-fluoroadenosine 9 was confirmed by a total synthesis as well as by its in vitro enzymatic conversion to metabolite 2 using the glucosyl transferase enzyme, NucGT.


Asunto(s)
Adenosina/análogos & derivados , Antibacterianos/biosíntesis , Streptomyces/metabolismo , Adenosina/biosíntesis , Adenosina/química , Antibacterianos/química , Estructura Molecular , Filogenia , Espectroscopía de Protones por Resonancia Magnética , Streptomyces/clasificación
3.
Proc Natl Acad Sci U S A ; 115(17): E3950-E3958, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29632183

RESUMEN

Understanding olfaction at the molecular level is challenging due to the lack of crystallographic models of odorant receptors (ORs). To better understand the molecular mechanism of OR activation, we focused on chiral (R)-muscone and other musk-smelling odorants due to their great importance and widespread use in perfumery and traditional medicine, as well as environmental concerns associated with bioaccumulation of musks with estrogenic/antiestrogenic properties. We experimentally and computationally examined the activation of human receptors OR5AN1 and OR1A1, recently identified as specifically responding to musk compounds. OR5AN1 responds at nanomolar concentrations to musk ketone and robustly to macrocyclic sulfoxides and fluorine-substituted macrocyclic ketones; OR1A1 responds only to nitromusks. Structural models of OR5AN1 and OR1A1 based on quantum mechanics/molecular mechanics (QM/MM) hybrid methods were validated through direct comparisons with activation profiles from site-directed mutagenesis experiments and analysis of binding energies for 35 musk-related odorants. The experimentally found chiral selectivity of OR5AN1 to (R)- over (S)-muscone was also computationally confirmed for muscone and fluorinated (R)-muscone analogs. Structural models show that OR5AN1, highly responsive to nitromusks over macrocyclic musks, stabilizes odorants by hydrogen bonding to Tyr260 of transmembrane α-helix 6 and hydrophobic interactions with surrounding aromatic residues Phe105, Phe194, and Phe207. The binding of OR1A1 to nitromusks is stabilized by hydrogen bonding to Tyr258 along with hydrophobic interactions with surrounding aromatic residues Tyr251 and Phe206. Hydrophobic/nonpolar and hydrogen bonding interactions contribute, respectively, 77% and 13% to the odorant binding affinities, as shown by an atom-based quantitative structure-activity relationship model.


Asunto(s)
Cicloparafinas/química , Modelos Moleculares , Receptores Odorantes/química , Células HEK293 , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Mutagénesis Sitio-Dirigida , Estabilidad Proteica , Estructura Secundaria de Proteína , Receptores Odorantes/genética , Receptores Odorantes/metabolismo
4.
Molecules ; 24(14)2019 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-31337084

RESUMEN

Origin traceability is important for controlling the effect of Chinese medicinal materials and Chinese patent medicines. Paris polyphylla var. yunnanensis is widely distributed and well-known all over the world. In our study, two spectroscopic techniques (Fourier transform mid-infrared (FT-MIR) and near-infrared (NIR)) were applied for the geographical origin traceability of 196 wild P. yunnanensis samples combined with low-, mid-, and high-level data fusion strategies. Partial least squares discriminant analysis (PLS-DA) and random forest (RF) were used to establish classification models. Feature variables extraction (principal component analysis-PCA) and important variables selection models (recursive feature elimination and Boruta) were applied for geographical origin traceability, while the classification ability of models with the former model is better than with the latter. FT-MIR spectra are considered to contribute more than NIR spectra. Besides, the result of high-level data fusion based on principal components (PCs) feature variables extraction is satisfactory with an accuracy of 100%. Hence, data fusion of FT-MIR and NIR signals can effectively identify the geographical origin of wild P. yunnanensis.


Asunto(s)
Melanthiaceae/química , Melanthiaceae/clasificación , Espectroscopía Infrarroja por Transformada de Fourier , Bases de Datos Factuales , Modelos Teóricos , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier/métodos
5.
Molecules ; 23(12)2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30563007

RESUMEN

Paris polyphylla, as a traditional herb with long history, has been widely used to treat diseases in multiple nationalities of China. Nevertheless, the quality of P. yunnanensis fluctuates among from different geographical origins, so that a fast and accurate classification method was necessary for establishment. In our study, the geographical origin identification of 462 P. yunnanensis rhizome and leaf samples from Kunming, Yuxi, Chuxiong, Dali, Lijiang, and Honghe were analyzed by Fourier transform mid infrared (FT-MIR) spectra, combined with partial least squares discriminant analysis (PLS-DA), random forest (RF), and hierarchical cluster analysis (HCA) methods. The obvious cluster tendency of rhizomes and leaves FT-MIR spectra was displayed by principal component analysis (PCA). The distribution of the variable importance for the projection (VIP) was more uniform than the important variables obtained by RF, while PLS-DA models obtained higher classification abilities. Hence, a PLS-DA model was more suitably used to classify the different geographical origins of P. yunnanensis than the RF model. Additionally, the clustering results of different geographical origins obtained by HCA dendrograms also proved the chemical information difference between rhizomes and leaves. The identification performances of PLS-DA and the RF models of leaves FT-MIR matrixes were better than those of rhizomes datasets. In addition, the model classification abilities of combination datasets were higher than the individual matrixes of rhizomes and leaves spectra. Our study provides a reference to the rational utilization of resources, as well as a fast and accurate identification research for P. yunnanensis samples.


Asunto(s)
Liliaceae/química , Melanthiaceae/química , Hojas de la Planta/química , Rizoma/química , Análisis Discriminante , Geografía , Análisis de los Mínimos Cuadrados , Medicina Tradicional , Análisis de Componente Principal , Espectroscopía Infrarroja por Transformada de Fourier/métodos
6.
Chemistry ; 22(31): 10998-1004, 2016 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-27374143

RESUMEN

We report a last-step fluorinase-catalyzed [(18) F]-fluorination of a cysteine-containing RGD peptide. The peptide was attached through sulfur to a modified and more hydrophilic variant of the recently disclosed Barbas linker which was itself linked to a chloroadenosine moiety via a PEGylated chain. The fluorinase was able to use this construct as a substrate for a transhalogenation reaction to generate [(18) F]-radiolabeled RGD peptides, which retained high affinity to cancer-cell relevant αv ß3 integrins.


Asunto(s)
Cisteína/química , Radioisótopos de Flúor/química , Humanos , Modelos Moleculares , Péptidos
7.
J Nutr ; 146(3): 465-73, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26843586

RESUMEN

BACKGROUND: Flavonoids have been implicated in the prevention of cardiovascular disease; however, their mechanisms of action have yet to be elucidated, possibly because most previous in vitro studies have used supraphysiological concentrations of unmetabolized flavonoids, overlooking their more bioavailable phenolic metabolites. OBJECTIVE: We aimed to explore the effects of phenolic metabolites and their precursor flavonoids at physiologically achievable concentrations, in isolation and combination, on soluble vascular cellular adhesion molecule-1 (sVCAM-1). METHOD: Fourteen phenolic acid metabolites and 6 flavonoids were screened at 1 µM for their relative effects on sVCAM-1 secretion by human umbilical vein endothelial cells stimulated with tumor necrosis factor alpha (TNF-α). The active metabolites were further studied for their response at different concentrations (0.01 µM-100 µM), structure-activity relationships, and effect on vascular cellular adhesion molecule (VCAM)-1 mRNA expression. In addition, the additive activity of the metabolites and flavonoids was investigated by screening 25 unique mixtures at cumulative equimolar concentrations of 1 µM. RESULTS: Of the 20 compounds screened at 1 µM, inhibition of sVCAM-1 secretion was elicited by 4 phenolic metabolites, of which protocatechuic acid (PCA) was the most active (-17.2%, P = 0.05). Investigations into their responses at different concentrations showed that PCA significantly reduced sVCAM-1 15.2-36.5% between 1 and 100 µM, protocatechuic acid-3-sulfate and isovanillic acid reduced sVCAM-1 levels 12.2-54.7% between 10 and 100 µM, and protocatechuic acid-4-sulfate and isovanillic acid-3-glucuronide reduced sVCAM-1 secretion 27.6% and 42.8%, respectively, only at 100 µM. PCA demonstrated the strongest protein response and was therefore explored for its effect on VCAM-1 mRNA, where 78.4% inhibition was observed only after treatment with 100 µM PCA. Mixtures of the metabolites showed no activity toward sVCAM-1, suggesting no additive activity at 1 µM. CONCLUSIONS: The present findings suggest that metabolism of flavonoids increases their vascular efficacy, resulting in a diversity of structures of varying bioactivity in human endothelial cells.


Asunto(s)
Flavonoides/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Hidroxibenzoatos/farmacología , Molécula 1 de Adhesión Celular Vascular/metabolismo , Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/genética
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 667-71, 2016 Mar.
Artículo en Zh | MEDLINE | ID: mdl-27400502

RESUMEN

The application of traditional Chinese medicine (TCM) and their preparations have a long history. With the deepening of the research, the market demand is increasing. However, wild resources are so limited that it can not meet the needs of the market. The development of wild and cultivated samples and research on accumulation dynamics of chemical component are of great significance. In order to compare composition difference of different parts (root, stem, and leaf) of wild and cultivated G. rigescens, Fourier infrared spectroscopy (FTIR) and second derivative spectra were used to analyze and evaluate. The second derivative spectra of 60 samples and the rate of affinity (the match values) were measured automatically using the appropriate software (Omnic 8.0). The results showed that the various parts of wild and cultivated G. rigescens. were high similar the peaks at 1732, 1 643, 1 613, 1 510, 1 417, 1 366, 1 322, 1 070 cm(-1) were the characteristic peak of esters, terpenoids and saccharides, respectively. Moreover, the shape and peak intensity were more distinct in the second derivative spectrum of samples. In the second derivative spectrum range of 1 800-600 cm(-1), the fingerprint characteristic peak of samples and gentiopicroside standards were 1 679, 1 613, 1 466, 1 272, 1 204, 1 103, 1 074, 985, 935 cm(-1). The characteristic peak intensity of gentiopicroside of roots of wild and cultivated samples at 1 613 cm(-1) (C-C) was higher than stems and leaves which indicated the higher content of gentiopicroside in root than in stem and leaves. Stems of wild samples at 1 521, 1 462 and 1 452 cm(-1) are the skeletal vibration peak of benzene ring of lignin, and the stem of cultivated sample have stronger peak than other samples which showed that rich lignin in stems. The iInfrared spectrum of samples were similar with the average spectral of root of wild samples, and significant difference was found for the correlation between second derivative spectrum of samples and average spectral of wild samples root, and the sequence of similarity was root > stem > leaf. Therefore, FTIR combined with second derivative spectra was an express and comprehensive approach to analyze and evaluate in the imperceptible differences among different parts of wild and cultivated of G. rigescens.


Asunto(s)
Gentiana/química , Fitoquímicos/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Glucósidos Iridoides/análisis , Hojas de la Planta/química , Raíces de Plantas/química , Tallos de la Planta/química , Programas Informáticos , Espectrofotometría Infrarroja
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1369-73, 2016 May.
Artículo en Zh | MEDLINE | ID: mdl-30001007

RESUMEN

The Processing of traditional Chinese medicine (TCM) is the key to clinical application of TCM, and processing has functions such as enhancing the efficacy, attenuating the toxicity andmoderating medicine property. In order to the realizing safe, reasonable and effective use of medicine in clinical, research on identification of TCM processed products is of great significance. The Gentiana rigescens samples which processed with five different methods were discriminated by Fourier transform infrared spectroscopy (FTIR). Baseline correction and normalization were used to pretreat all original spectra and the noise was cut off. The spectra range was from 3 400 to 600 cm-1. The effect of multiple scattering correction and standard normal variable on the model were observed and compared. Samples were divided into calibration set and prediction set at the ratio of 3∶1. The principal component analysis (PCA) was applied to reduce data dimensionality and discriminant analysis model was established. The result indicated that the main absorption peaks of samples were 3 378, 2 922, 1 732, 1 610, 1 417, 1 366, 1 316, 1 271, 1 068, 1 048 cm- 1 which 1 738, 1 643, 1 613, 1 420, 1 051 cm-1 as to gentiopicrin; 1 068, 1 048, 935 cm-1 as to carbohydrate. The accumulation contribution rate of first three principal components is 94.05%. Most of the information reflected the original data. There were differences among different samples. The result of discriminant analysis showed that the recognition rate of G. rigescens samples could achieve to 100% based on baseline correction and normalization treatment combined with MSC with the precondition of principal component scores being 10. In conclusion, FTIR is a feasible, rapid and non-destructive method to discriminate G. rigescens samples wtih different processing methods. It also provided reference for discrimination of processed products of medicine materials.


Asunto(s)
Gentiana , Espectroscopía Infrarroja por Transformada de Fourier , Calibración , Análisis Discriminante , Glucósidos Iridoides , Análisis de Componente Principal
10.
Anal Chem ; 86(20): 10052-8, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-24828315

RESUMEN

The metabolic fate of anthocyanins until recently was relatively unknown, primarily as a result of their instability at physiological pH and a lack of published methods for isolating and identifying their metabolites from biological samples. The aim of the present work was to establish methods for the extraction and quantification of anthocyanin metabolites present in urine, serum, and fecal samples. 35 commercial and 10 synthetic analytes, including both known and predicted human and microbial metabolites of anthocyanins, were obtained as reference standards. HPLC and MS/MS conditions were optimized for organic modifier, ionic modifier, mobile phase gradient, flow rate, column type, MS source, and compound dependent parameters. The impact of sorbent, solvent, acid, preservative, elution, and evaporation on solid phase extraction (SPE) efficiency was also explored. The HPLC-MS/MS method validation demonstrated acceptable linearity (R(2), 0.997 ± 0.002) and sensitivity (limits of detection (LODs): urine, 100 ± 375 nM; serum, 104 ± 358 nM; feces 138 ± 344 nM), and the final SPE methods provided recoveries of 88.3 ± 17.8% for urine, 86.5 ± 11.1% for serum, and 80.6 ± 20.9% for feces. The final methods were applied to clinical samples derived from an anthocyanin intervention study, where 36 of the 45 modeled metabolites were detected within urine, plasma, or fecal samples. The described methods provide suitable versatility for the identification and quantification of an extensive series of anthocyanin metabolites for use in future clinical studies exploring absorption, distribution, metabolism, and elimination.


Asunto(s)
Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem
11.
Angew Chem Int Ed Engl ; 53(34): 8913-8, 2014 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-24989327

RESUMEN

A strategy for last-step (18)F fluorination of bioconjugated peptides is reported that exploits an "Achilles heel" in the substrate specificity of the fluorinase enzyme. An acetylene functionality at the C-2 position of the adenosine substrate projects from the active site into the solvent. The fluorinase catalyzes a transhalogenation of 5'-chlorodeoxy-2-ethynyladenosine (ClDEA) to 5'-fluorodeoxy-2-ethynyladenosine (FDEA). Extending a polyethylene glycol linker from the terminus of the acetylene allows the presentation of bioconjugation cargo to the enzyme for (18)F labelling. The method uses an aqueous solution (H2(18)O) of [(18)F]fluoride generated by the cyclotron and has the capacity to isotopically label peptides of choice for positron emission tomography (PET).


Asunto(s)
Proteínas Bacterianas/química , Flúor/química , Oligopéptidos/química , Oxidorreductasas/química , Cromatografía Líquida de Alta Presión , Modelos Moleculares , Conformación Proteica , Radioquímica , Espectrofotometría Ultravioleta , Especificidad por Sustrato , Agua/química
12.
Org Biomol Chem ; 11(27): 4551-8, 2013 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-23733207

RESUMEN

The utility of 5-fluoro-5-deoxyribose (FDR) as an efficient bioconjugation agent for radiolabelling of the RGD peptides c(RGDfK) and c(RGDfC) is demonstrated. The bioconjugation is significantly superior to that achieved with 2-fluoro-2-deoxyglucose (FDG) and benefits from the location of the fluorine at C-5, and that ribose is a 5-membered ring sugar rather than a 6-membered ring. Both features favour ring opening to the aldehydic form of the sugar to promote smooth oxime ligation with aminooxy ether functionalised peptides. [(18)F]FDR was prepared in this study by synthesis from fluoride-18 using an automated synthesis protocol adapting that used routinely for [(18)F]FDG. c(RGDfK) was functionalised with an aminooxyacetyl group (Aoa) via its lysine terminus, while c(RGDfC) was functionalised with an aminooxyhexylmaleimide (Ahm) through a cysteine-maleimide conjugation. Bioconjugation of [(18)F]FDR to c(RGDfC)-Ahm proved to be more efficient than c(RGDfK)-Aoa (92% versus 65%). The unlabelled ((19)F) bioconjugates c(RGDfK)-Aoa-FDR and c(RGDfC)-Ahm-FDR were prepared and their in vitro affinity to purified integrin αvß3 was determined. c(RGDfK)-Aoa-FDR showed the greater affinity. Purified "hot" bioconjugates c(RGDfK)-Aoa-[(18)F]FDR and c(RGDfC)-Ahm-[(18)F]FDR were assayed by incubation with MCF7, LNCaP and PC3 cell lines. In both cases the conjugated RGD peptides showed selectivity for PC3 cells, which express αvß3 integrin, with the c(RGDfK)-Aoa-[(18)F]FDR demonstrating better binding, consistent with its higher in vitro affinity. The study demonstrates that [(18)F]FDR is an efficient bioconjugation ligand for RGD bioactive peptides.


Asunto(s)
Fluorodesoxiglucosa F18/química , Integrina alfaVbeta3/análisis , Oligopéptidos/química , Tomografía de Emisión de Positrones/métodos , Línea Celular Tumoral , Fluorodesoxiglucosa F18/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Oligopéptidos/metabolismo
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(2): 471-5, 2013 Feb.
Artículo en Zh | MEDLINE | ID: mdl-23697135

RESUMEN

In this study, Panax notoginseng samples were extracted by chloroform, ethanol and water, or by those extracted solution with 5% vanillin sulfuric acid to establish two kinds of UV fingerprint of P. notoginseng which were compared by applying the common and variation peak ratio dual index sequence analysis method and SIMCA software qualitative analysis. The results indicated that the optimization extraction time of P. notoginseng samples was 20 min with chloroform, ethanol and water extraction, but the fingerprint differed significantly after add vanillin sulfuric acid. The common peak ratios of UV fingerprint of P. notoginseng were scattered. The minimum was 25% (Y5-Y8), while the maximum was 84.38% (Y11-Y13, Y20-Y21). The maximum variation peak ratio was 177.78% (Y8-Y5), meanwhile, the variation peak ratios of several samples were more than 100%. However, the common peak ratios of UV fingerprint of P. notoginseng with vanillin sulfuric acid were concentrated (distributed in the range of 50%-70%): the minimum was 42.86%(Y1-Y19), whereas the maximum was 79.55% (Y22-Y23); the range of the variation peak ratios was also smaller with the ranges of 20%-50% in general. The result of the dual index sequence analysis was agreement with the fingerprint implied. The similarity of the UV fingerprint of the extracts of P. notoginseng after adding vanillin sulfuric acid was greater than before. Both the ages and origin was related with the difference of UV fingerprint. The similarity of the two samples with same age was more significant than those with different ages. The similarity and difference between samples was no correlation with the distance of geographic space, the near origin samples maybe have a significant similarity or difference. This method appears as good alternative for evaluate quality of the P. notoginseng and can distinguish at least two samples quantitatively, duo to it reaches the limitation of the multiple methods which only could be used to indistinctly distinguish herbs.


Asunto(s)
Panax notoginseng/química , Espectrofotometría Ultravioleta/métodos , Benzaldehídos/química , Colorimetría/métodos , Control de Calidad , Ácidos Sulfúricos/química
14.
Org Lett ; 25(37): 6802-6807, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37682007

RESUMEN

The (ß,ß',ß″-trifluoro)-tert-butyl (TFTB) group has received very little attention in the literature. This work presents a direct synthesis of this group and explores its properties. The TFTB group arises when the methyl groups of a tert-butyl moiety are exchanged for fluoromethyl groups. Sequential fluoromethylations result in a decrease of Log P (increasing hydrophilicity), ultimately by 1.7 Log P units in the TFTB group relative to that of tert-butyl benzene itself. A focus is placed on synthetic transformations, conformational analysis, and metabolism of the TFTB group in the context of presenting a favorable profile as a motif for the discovery of bioactives.

15.
Anal Chem ; 83(23): 9191-6, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22029608

RESUMEN

We have developed a nanotube-based colorimetric probe using multiwalled carbon nanotubes (MWNTs), anti-immunoglobulin G (anti-IgG), and horseradish peroxidase (HRP). The probe was used as an alternative to conventional colorimetric conjugates to obtain amplified signals in a sandwich-type immunoassay for ataxia telangiectasia mutated (ATM), a potential biomarker for radiation doses and cancers. Results show that the MWNT-based probe colorimetry was 5000 times more sensitive than a conventional ELISA, while its concentration range was 10,000 times wider than that of the latter. Its limit of detection (LOD) was 0.2 fg/mL (54 aM, ~32 molecules in 1 µL samples). Control experiments showed that detection of ATM molecules at the picogram-level could still be achieved in samples that contained protein makers present at more than 100 times the ATM concentration, demonstrating the high specificity of the technique. The MWNT-based probe also has the potential to become a universal probe for colorimetric assays of most protein markers because it can recognize the associated rabbit polyclonal antibodies.


Asunto(s)
Proteínas de Ciclo Celular/análisis , Colorimetría , Proteínas de Unión al ADN/análisis , Nanotubos de Carbono/química , Proteínas Serina-Treonina Quinasas/análisis , Proteínas Supresoras de Tumor/análisis , Animales , Proteínas de la Ataxia Telangiectasia Mutada , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/inmunología , Proteínas de Ciclo Celular/inmunología , Proteínas de Unión al ADN/inmunología , Peroxidasa de Rábano Silvestre/metabolismo , Inmunoensayo , Inmunoglobulina G/inmunología , Proteínas Serina-Treonina Quinasas/inmunología , Conejos , Proteínas Supresoras de Tumor/inmunología
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120070, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34153549

RESUMEN

Dendrobium Sw., as a traditional herb and function food with over 1500 years of history, shows a significant effect in improving immunity and fatigue resistance. However, due of course the large number of species and the quality fluctuating in different species, a fast and effective discrimination method is in need. Recently, spectroscopic techniques combined with chemometrics have become an effective method for low-cost and fast analysis in food and herb. Nevertheless, chemometrics method which based on one-dimensional spectral dataset still encounter the difficulty that can not effectively extract useful information from the spectra. Different from one-dimensional spectra, the two-dimensional correlation spectroscopy (2DCOS) can reveal more detail information of the spectral dataset. Moreover, the appearance of convolutional neural network makes the application of deep learning in image recognition faster and more accurate. In this study, a novel method 2DCOS combined with residual convolutional neural network (ResNet) was used to discriminate the 20 species of Dendrobium. Five feature bands were selected based on spectrum standard deviation (SDD) method in NIR and MIR spectra. Moreover, the models based on full band, total five feature bands, and their fusion-bands had been compared. The results showed that two feature bands 1800-450 cm-1 and 2400-1900 cm-1 displayed 100% accuracy in both training set and test set. And also, the accurate discrimination of 10% external validation showed that these models have good generalization ability. In conclusion, 2DCOS combined with ResNet could be an effective and accurate method for classify different Dendrobium species.


Asunto(s)
Dendrobium , Redes Neurales de la Computación , Análisis Espectral
17.
Ann Anat ; 234: 151665, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33400984

RESUMEN

INTRODUCTION: Amelogenin (AMEL) plays critical roles during enamel and dentin matrix deposition and mineralization. Most studies focused on the expression patterns of AMEL through the bud, cap, and bell stages. The spatial-temporal expression of AMEL protein during different mineralization stages, especially from presence of crypts to crown completed stages, remains unknown. Thus, the distribution pattern of AMEL in tooth crown formation from Nolla Stage 1 to 6 was investigated. METHODS: Porcine mandibular molar tooth germs from Nolla Stage 1 to 6 were obtained. The dynamic morphologic changes of tooth germs were examined by X-ray and surgical operating microscope. The AMEL protein expression was evaluated immunohistochemically, then analyzed semi-quantitatively, and further visualized via heat map. RESULTS: Tooth germs continuously increased in size from Nolla Stage 1 to 6. AMEL expression in the newly formed enamel kept negative, but presented intensively positive in the previously formed enamel from Stage 1 to 3. The adjacent enamel-dentin junction (EDJ) was strongly positive during the whole process. In predentin, AMEL was weakly seen at Stage 1 and then dramatically up-regulated from Stage 2 to Stage 3, then down-regulated but was still apparently seen in the whole process. AMEL expression in dentin was decreased during dentin matrix secretion and mineralization. CONCLUSIONS: This study identified the dynamic distribution of AMEL during porcine tooth crown formation. Semi-quantitative analysis and heat map emerged as reliable indicators in demonstrating AMEL distribution pattern.


Asunto(s)
Proteínas del Esmalte Dental , Corona del Diente , Amelogenina , Animales , Diente Molar , Porcinos , Germen Dentario
18.
Oncol Lett ; 22(5): 754, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34539858

RESUMEN

In the present study, due to the complex and numerous targets of Sarcandrae Herb (also known as Zhong Jie Feng), network pharmacology was performed to analyze its therapeutic effect on 2 cervical cancer cell lines, which could assist with the development of novel therapies. The results suggested that the natural flavonoid quercetin (Que), the effective antitumor ingredient in SH, which is widely present in a variety of plants, may depend on the target, EGFR. Previous studies have shown that EGFR serves a crucial role in the occurrence and development of cervical cancer, but its downstream molecules and regulatory mechanisms remain unknown. The anti-cervical cancer cell properties of Que, which are present in ubiquitous plants, were examined in vitro to identify the association between Que and its underlying pathway using MTT assays, flow cytometry, western blot analysis and Transwell assays. It was found that Que reduced cervical cancer cell viability, promoted G2/M phase cell cycle arrest and cell apoptosis, as well as inhibited cell migration and invasion. The Tyr1068 phosphorylation site of EGFR and the corresponding ERK target were also examined and the 2 kinases were markedly activated by Que. Furthermore, the EGFR inhibitor, afatinib and the ERK inhibitor, U0126 blocked the increase of EGFR and ERK phosphorylation, and resulted in a notable enhancement of apoptosis and cell cycle arrest. Therefore, to the best of our knowledge, the current results provided the first evidence that EGFR and ERK activation induced by Que could resist Que-induced anticancer activities. On this basis, the present study determined the role of EGFR and the underlying signaling pathways involved in the anti-cervical cancer malignant behavior induced by Que and identified the negative regulatory association.

19.
J Ethnopharmacol ; 278: 114293, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34102270

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Paris L. (Liliaceae) consisted of 33 species, of which the study focused on Paris polyphylla Smith, P. polyphylla var. chinensis (Franch.) Hara, and P. polyphylla Smith var. yunnanensis (Franch.) Hand. -Mazz. Due of course to the good effects of analgesia and hemostasis, it was traditionally used to treat trauma by folk herbalists. AIM OF THIS REVIEW: This study summarized the traditional uses, distributions, phytochemical components, pharmacological properties, and toxicity evaluation of the genus Paris, and reviewed the economic value of cultivate P. polyphylla. This aim was that of providing a new and comprehensive recognition of these medicinal plants for the further utilization of Paris plants. MATERIALS AND METHODS: The literature about traditional and folk uses of genus Paris was obtained from Duxiu Search, and China National Knowledge Infrastructure (CNKI). The other literature about genus Paris was searched online on Web of Science, PubMed, Google Scholar, Baidu Scholar, Scifinder database, and Springer research. The Scientific Database of China Plant Species (DCP) (http://db.kib.ac.cn/Default.aspx) databases were used to check the scientific names and provide species, varieties, and distribution of genus Paris. The botany studies information of genus Paris was available online from Plant Plus of China (www.iplant.cn). All the molecular structures of chemical compounds displayed in the text were produced by ChemBioDraw Ultra 14.0. RESULTS: The plants of genus Paris, containing about 33 species and 15 varieties, are mainly distributed in Southwest China (Yunnan, Sichuan, and Guizhou provinces). More than 320 chemical components have been isolated from genus Paris since 2020, including steroidal saponins, C-21 steroids, phytosterols, insect hormones, pentacyclic triterpenes, flavonoids, and other compounds. Arrays of pharmacological investigations revealed that compounds and extracts of Paris species possess a wide spectrum of pharmacological effects, such as antitumor, cytotoxic, antimicrobial, antifungal, hemostatic, and anti-inflammatory activities. The studies about toxicity evaluation suggested that Rhizome Paridis had slight liver toxicity. CONCLUSIONS: The dried rhizomes of P. polyphylla, P. polyphylla var. chinensis, and P. polyphylla var. yunnanensis were used to treat wound, bleeding, and stomachache, etc. in folk medicine. Phytochemistry researches showed that different species had pretty similarities especially in terms of chemical constituents. Pharmacological studies witnessed that Rhizome Paridis has various activities. Among these activities, steroidal saponins were the main active ingredients. Furthermore, an important aspect responsible for increasing interest in genus Paris is the use of antifertility-nonhormonal contraceptives by women. Also, the development of TCM (Traditional Chinese medicine) planting industry can improve the income of ethnic minorities and promote economic development.


Asunto(s)
Liliaceae/química , Fitoquímicos , Fitoterapia , Plantas Medicinales/química , Humanos , Medicina Tradicional
20.
Crit Rev Anal Chem ; 50(5): 405-423, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31357868

RESUMEN

Genus Paris mainly distributed in Asia and served as traditional ethnobotanical medicine in China, India, and Nepal. The main aim of this study was to review ethnic minorities medicinal records for Paris in China, the Chinese patent medicines based on Paris materials and the authentication and quality evaluation of Paris based on two parts of analytical technologies and data analysis. This article reviews approximately 100 articles from 1980 to 2019 published on the research of genus Paris materials and their Chinese patent medicines. Additionally, local books were also searched. Five major kinds of chemical techniques have been applied to authentication and quality assessment of Paris and among them, chromatography was the most widely used one, and DNA barcoding technique was the most worth further study. Additionally, more than 70% of the research studies were analyzed by unsupervised pattern-recognition techniques combined with analytical technologies such as spectroscopy. Meanwhile, the data fusion strategy with higher classification ability combined multiple supervised pattern-recognition techniques have been gradually applied to authentication assessment. The optimal analytical technologies and methods applied to Paris qualities for authentication and quality evaluation are greatly important, which could promote the development and utilization for ethnomedicines of Paris.


Asunto(s)
Liliaceae/química , Plantas Medicinales/química , Medicina Tradicional China
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