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1.
Molecules ; 23(5)2018 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-29734695

RESUMEN

Discrimination of Gastrodia elata (G. elata) geographical origin is of great importance to pharmaceutical companies and consumers in China. this paper focuses on the feasibility of near infrared spectrum (NIRS) combined multivariate analysis as a rapid and non-destructive method to prove its fit for this purpose. Firstly, 16 batches of G. elata samples from four main-cultivation regions in China were quantified by traditional HPLC method. It showed that samples from different origins could not be efficiently differentiated by the contents of four phenolic compounds in this study. Secondly, the raw near infrared (NIR) spectra of those samples were acquired and two different pattern recognition techniques were used to classify the geographical origins. The results showed that with spectral transformation optimized, discriminant analysis (DA) provided 97% and 99% correct classification for the calibration and validation sets of samples from discriminating of four different main-cultivation regions, and provided 98% and 99% correct classifications for the calibration and validation sets of samples from eight different cities, respectively, which all performed better than the principal component analysis (PCA) method. Thirdly, as phenolic compounds content (PCC) is highly related with the quality of G. elata, synergy interval partial least squares (Si-PLS) was applied to build the PCC prediction model. The coefficient of determination for prediction (Rp²) of the Si-PLS model was 0.9209, and root mean square error for prediction (RMSEP) was 0.338. The two regions (4800 cm−1⁻5200 cm−1, and 5600 cm−1⁻6000 cm−1) selected by Si-PLS corresponded to the absorptions of aromatic ring in the basic phenolic structure. It can be concluded that NIR spectroscopy combined with PCA, DA and Si-PLS would be a potential tool to provide a reference for the quality control of G. elata.


Asunto(s)
Cromatografía Líquida de Alta Presión , Gastrodia/química , Espectroscopía Infrarroja Corta , China , Análisis Discriminante , Gastrodia/clasificación , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Análisis de Componente Principal , Control de Calidad
2.
Bioorg Med Chem Lett ; 27(17): 4185-4189, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28757067

RESUMEN

A series of novel 4(1H)-quinolone derivatives was synthesized and evaluated for antiproliferative activity in vitro. The results showed that these compounds exhibited more potent antiproliferative effect against a panel of human tumorcelllines than the lead compound 7-chloro-4(1H)-quinolone 1. Compound 7e was found to be the most potent antiproliferative agent and to exhibit selective cytotoxic activity against HepG2 cell lines with IC50 value lower than 1.0µM. Annexin V/FITC-PI assay showed that compound 7e induced apoptosis in HepG2 cells with a dose-dependent manner. Western blotting analysis indicated that compound 7e induced cell cycle arrest in G2/M phase by p53-depedent pathway.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Descubrimiento de Drogas , Quinolonas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Quinolonas/síntesis química , Quinolonas/química , Relación Estructura-Actividad
3.
Plants (Basel) ; 12(12)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37376000

RESUMEN

Karst desertification control forests are essential for ecosystem multi functionality, but the trade-offs/synergies are unclear for forest ecosystem services. In order to clarify the trade-offs/synergies, this study was conducted on eight forest communities in a karst desertification control area and was based on vegetation surveys and structural and functional monitoring. It analyzes water holding capacity, species diversity, soil conservation, and carbon storage characteristics and their trade-off/synergies. The results indicate the following: (1) The Cladrastis platycarpa + Cotinus coggygria community (H1) had the highest water holding capacity and species diversity with values of 252.21 t·hm-2 and 2.56, respectively. Soil conservation was highest in the Zanthoxylum bungeanum + Glycine max community (H6), with an index value of 1.56. Carbon storage was the greatest in the Tectona grandis community (H8), at 103.93 t·hm-2. The results of these studies have shown that there are significant differences in different types of forest community ecosystem services. (2) Water holding capacity, species diversity, soil conservation, and carbon storage, all have synergistic relationships, suggesting a trend towards synergistic enhancement between the services. (3) The species diversity of the forest ecosystems was shown to be in a trade-off with carbon storage and soil conservation, which suggests that the services are in competition with each other. To further improve the service capacity of forest ecosystems, the trade-offs between the regulation of forest community structure and function and the improvement of services should be optimized.

4.
Microsc Res Tech ; 85(9): 3050-3055, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35567791

RESUMEN

The long-term stability of implants requires good peri-implant soft tissue sealing. Calcium ion (Ca2+ ) was loaded onto titanium surface by a hydrothermal method. In vitro, the morphology and composition of titanium surfaces were determined by scanning electron microscopy and energy-dispersive spectroscopy; proliferation of hGF-1 cells was measured by the CCK-8 assay; immunofluorescence staining was done to detect adherent proteins on titanium surface. In vivo, the degree of attachment between the implant and the surrounding soft tissue was measured by horseradish peroxidase (HRP). The percentage of hGF-1 cells adhering in the Ca group was significantly higher (p < .01); the fluorescence of integrin-ß1 and F-actin in the Ca group was stronger; Ca group had the shorter length of HRP (p < .01). Ca2+ can be added to the surface of titanium by a hydrothermal method and it will be more beneficial for soft tissue early sealing. HIGHLIGHTS: A simple method to form micron crystals on titanium surface. The micron crystal promotes the attachment of human gingival fibroblasts. Facilitates early and rapid formation of soft-tissue sealing around implants.


Asunto(s)
Implantes Dentales , Titanio , Adhesión Celular , Proliferación Celular , Células Cultivadas , Fibroblastos , Encía , Humanos , Propiedades de Superficie , Titanio/química , Titanio/farmacología
5.
Ann Transl Med ; 10(5): 248, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35402592

RESUMEN

Background: To evaluate the effects of four ceramic primers and two cement types on the bonding strength and durability between zirconia and resin cement. Methods: A total of 115 polished and air-abraded zirconia blocks were randomly divided into five groups (with 23 in each group) to test the performance of various primers. Meanwhile, all primer samples were divided into two subgroups randomly to measure the difference between the two cement types. Group No treat - Clearfil SA Cement (NT-C); group No treat - RelyX Unicem Cement (NT-U); group Z-Prime Plus - Clearfil SA Cement (ZPP-C); group Z-Prime Plus - RelyX Unicem Cement (ZPP-U); group Rely X Ceramic Primer - Clearfil SA Cement (RCP-C); group Rely X Ceramic Primer - RelyX Unicem Cement (RCP-U); group Clearfil Ceramic Primer - Clearfil SA Cement (CCP-C); group Clearfil Ceramic Primer - RelyX Unicem Cement (CCP-U); group Monobond-S - Clearfil SA Cement (MS-C); group Monobond-S - RelyX Unicem Cement (MS-U). According to the type of cement, the specimens were randomly selected for electron microscope scanning and energy spectrum analysis, and the tightness of zirconium porcelain resin adhesive interface was observed. The bonding strength of different adhesives and aging experiments were tested by shear test mode, and the shear strength of each experimental group was analyzed by one variable three factor analysis of variance. Results: All primers in the treated groups maintained a pristine structure without micro-crack, while the non-primer treatment sample exhibited obvious micro-cracks. Furthermore, among the four primers, the sample treated with Clearfil Ceramic Primer (CCP) obtained the highest bonding strength, with a statistically significant difference (P<0.05). However, cohesive failure mainly occurred in the CCP group before thermal cycles, and mixed failure occurred after thermal cycles. Conclusions: CCP is the superior primer, and can improve the bonding strength between zirconia and resin cement. Because the thermal cycles have a significantly adverse effect on the shear bond strength, CCP can be helpful in improving the durability of the zirconia bonding strength. Furthermore, the two cement types exhibited a similar bonding performance for zirconia.

6.
Org Lett ; 24(25): 4586-4591, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35714047

RESUMEN

The intermolecular addition of allylic copper species generated from diene and copper hydride remains elusive. Herein copper hydride catalyzed asymmetric cross reductive coupling of conjugated dienes and ketoimines including trifluoromethyl ketoimines and α-iminoacetates was first achieved using chiral Ph-BPE as the ligand, providing rapid access to structurally and optically enriched homoallylic amines containing two vicinal stereogenic centers with up to 95% yield, 99% ee, and 11:1 diastereoselectivities.


Asunto(s)
Cobre , Polienos , Aminas , Catálisis , Estereoisomerismo
7.
J Anal Methods Chem ; 2020: 8847277, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33204575

RESUMEN

Steaming is a vital unit operation in traditional Chinese medicine (TCM), which greatly affects the active ingredients and the pharmacological efficacy of the products. Near-infrared (NIR) spectroscopy has already been widely used as a strong process analytical technology (PAT) tool. In this study, the potential usage of NIR spectroscopy to monitor the steaming process of Gastrodiae rhizoma was explored. About 10 lab scale batches were employed to construct quantitative models to determine four chemical ingredients and moisture change during the steaming process. Gastrodin, p-hydroxybenzyl alcohol, parishin B, and parishin A were modeled by different multivariate calibration models (SMLR and PLS), while the content of the moisture was modeled by principal component regression (PCR). In the optimized models, the root mean square errors of prediction (RMSEP) for gastrodin, p-hydroxybenzyl alcohol, parishin B, parishin A, and moisture were 0.0181, 0.0143, 0.0132, 0.0244, and 2.15, respectively, and correlation coefficients (R p 2) were 0.9591, 0.9307, 0.9309, 0.9277, and 0.9201, respectively. Three other batches' results revealed that the accuracy of the model was acceptable and that was specific for next drying step. In addition, the results demonstrated the method was reliable in process performance and robustness. This method holds a great promise to replace current subjective color judgment and time-consuming HPLC or UV/Vis methods and is suitable for rapid online monitoring and quality control in the TCM industrial steaming process.

8.
Zhong Yao Cai ; 30(4): 401-3, 2007 Apr.
Artículo en Zh | MEDLINE | ID: mdl-17674787

RESUMEN

OBJECTIVE: To provide the scientific basis for identification and utilization of Memorialis hirta ( BL) Wedd. METHODS: Macroscopical identification and microscopic identification. RESULTS: To make system pharmacognostical studies on stalk and fine powder of Memorialis hirta (BL) Wedd. CONCLUSION: These characteristic can provide the scientific basis for identification of Memorialis hirta (BL) Wedd.


Asunto(s)
Tallos de la Planta/anatomía & histología , Plantas Medicinales/anatomía & histología , Urticaceae/anatomía & histología , Medicamentos Herbarios Chinos/aislamiento & purificación , Farmacognosia/métodos , Tallos de la Planta/citología , Plantas Medicinales/citología , Polvos , Urticaceae/citología
9.
Mol Med Rep ; 16(2): 1269-1277, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28627590

RESUMEN

In Parkinson's disease (PD), microglial activation-mediated neuroinflammation is associated with dopaminergic neurons degeneration in the substantia nigra pars compacta. Previous studies that have investigated this neurodegenerative disease have reported that the Sonic hedgehog (SHH) signaling pathway, through inhibiting the inflammatory processes, exerts a beneficial neuroprotective effect. However, the mechanisms underlying the anti­inflammatory and neuroprotective effects of this signaling pathway remain poorly understood. The present study aimed to further investigate these mechanisms in vitro and in vivo. At first, BV2 microglial cells treated with lipopolysaccharide (LPS) were used to induce an inflammatory response. It was observed that the activation of SHH signaling by Purmorphamine attenuated the LPS­induced inflammatory response, increased the expression of transforming growth factor­ß1 through the phosphatidylinositol 3­kinase (PI3K)/AKT serine/threonine kinase (Akt) intracellular signaling pathway and inhibited nuclear receptor subfamily 4 group A member 2, independently of the PI3K/Akt signaling pathway. Furthermore, the blockade of the PI3K/Akt signaling pathway by intranasal administration of LY294002, significantly reduced the SHH­associated neuroprotective effects on dopaminergic neurons, improved motor functions, and increased the microglial activation and inflammatory response in a mouse model of PD induced using 1­methyl­4­phenyl­1,2,3,6­tetrahydropyridine. In conclusion, the data of the present study reported that anti­inflammatory and neuroprotective effects can be obtained in BV2 microglial cells and in a mouse model of PD by successive activation of the SHH and PI3K/Akt signaling pathways.


Asunto(s)
Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Proteínas Hedgehog/metabolismo , Morfolinas/farmacología , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Purinas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular , Modelos Animales de Enfermedad , Inflamación/metabolismo , Masculino , Ratones , Microglía/efectos de los fármacos , Microglía/metabolismo , Fármacos Neuroprotectores/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/fisiopatología
10.
Artículo en Zh | WPRIM | ID: wpr-907046

RESUMEN

Objective@# To explore the design and manufacture of anatomical healing abutment for mandibular first molar implant in order to provide more choices for clinical healing abutment@*Methods@# The buccal lingual diameter and mesial distal diameter of the tooth neck, as well as the slope data of the four axial surfaces of the natural isolated teeth, were obtained by scanning the isolated mandibular first molar with a shining scanner. After statistical analysis of the data, the anatomical healing abutment of the mandibular first molar was designed and constructed using computer aided design/computer aided manufacturing (CAD/CAM).@*Results@#The mean buccal and lingual diameters of the mesial and distal diameters of the isolated mandibular first molars were (8.54 ± 0.78) mm and (7.87 ± 0.86) mm, and the tooth neck slopes of each axial surface of the isolated mandibular first molars were 17.53 °(buccal), 14.41 °(lingal), 13.40 °(mesial) and 13.43 °(distal), respectively. Three anatomical healing abutments with different peripheral diameters and heights of 5 mm were obtained according to a certain proportion of reduction of the natural teeth of the mandibular first molars@*Conclusion@#The anatomical healing abutment of the mandibular first molar can be quickly obtained by Shining scanning and CAD/CAM technology.

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