The Experts below are selected from a list of 1857 Experts worldwide ranked by ideXlab platform

Sicen Wang - One of the best experts on this subject based on the ideXlab platform.

  • screening active anti breast cancer compounds from cortex magnolia officinalis by mcf 7 cell membrane chromatography coupled with uhplc esi ms ms
    Analytical Methods, 2017
    Co-Authors: Ping Zhang, Xiaofang Hou, Muhammad Saqib, Sicen Wang
    Abstract:

    Breast cancer is one of the most frequent malignant tumors in females. Extracts from Cortex Magnolia Officinalis (CMO) have shown the ability to inhibit the growth of breast cancer cells. In the present study, we developed MCF-7 cell membrane chromatography (CMC) combined with a UHPLC-ESI-MS/MS method to screen and identify the active components from the extract of CMO. Sorafenib and Dexamethasone Acetate were used as positive and negative control drugs, respectively, to investigate the suitability of this system. Under optimum experimental conditions, two components showed strong retention characteristics on the MCF-7 cell membrane chromatographic column. These compounds were identified as magnolol and honokiol by UHPLC-ESI-MS/MS. Cytotoxicity assay and Hoechst 33258 staining were done to investigate the anti-proliferative activity of the two compounds. The MTT results showed that MCF-7 cell viability decreased gradually in a dose-dependent manner during 48 h. The IC50 of magnolol and honokiol were 85.4 μM and 58.1 μM, respectively. After Hoechst 33258 staining, the cells were observed with bright blue nuclei due to karyopyknosis and chromatin condensation. The screening results showed that both magnolol and honokiol were promising active components of CMO extract having an inhibitory effect on MCF-7 cell growth. This two-dimensional method CMC-UHPLC-ESI-MS/MS could have potential utility for screening target components from traditional Chinese medicines.

  • screening anti tumor compounds from ligusticum wallichii using cell membrane chromatography combined with high performance liquid chromatography and mass spectrometry
    IEEE Journal of Solid-state Circuits, 2015
    Co-Authors: Tao Zhang, Liuxin Feng, Yuanyuan Ding, Sicen Wang
    Abstract:

    Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry was developed. Tyrosine 367 Cysteine-HEK293 cells were used as the cell membrane stationary phase. The specificity and reproducibility of the cell membrane chromatography was evaluated using 1-tert-butyl-3-{2-[4-(diethylamino)butylamino]-6-(3,5-dimethoxyphenyl)pyrido[2,3-d]pyrimidin-7-yl}urea, nimodipine and Dexamethasone Acetate. Then, anti-tumor components acting on Tyrosine 367 Cysteine-fibroblast growth factor receptor 4 were screened and identified from extracts of Ligusticum wallichii. Components from the extract were retained on the cell membrane chromatographic column. The retained fraction was directly eluted into high-performance liquid chromatography with mass spectrometry system for separation and identification. Finally, Levistolide A was identified as an active component from Ligusticum wallichii extracts. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide-formazan colorimetric assay revealed that Levistolide A inhibits proliferation of overexpressing the mutated receptor cells with dose-dependent manner. Phosphorylation of fibroblast growth factor receptor 4 was also decrease under Levistolide A treatment. Flex dock simulation verified that Levistolide A could bind with the tyrosine kinase domain of fibroblast growth factor receptor 4. Therefore, Levistolide A screened by the cell membrane chromatography combined with high-performance liquid chromatography and mass spectrometry can arrest cell growth. In conclusion, the two-dimensional high-performance liquid chromatography method can screen and identify potential anti-tumor ingredients that specifically act on the tyrosine kinase domain of the mutated fibroblast growth factor receptor 4.

Shen Gao - One of the best experts on this subject based on the ideXlab platform.

  • plga peg plga hydrogel for ocular drug delivery of Dexamethasone Acetate
    Drug Development and Industrial Pharmacy, 2010
    Co-Authors: Yuan Gao, Yan Sun, Fuzheng Ren, Shen Gao
    Abstract:

    Aim: This study aims to investigate the suitability of thermosensitive triblock polymer poly-(dl-lactic acid-co-glycolic acid) (PLGA)–polyethylene glycol (PEG)–PLGA as a matrix material for ocular delivery of Dexamethasone Acetate (DXA). Methods: The copolymer was synthesized and evaluated for its thermosensitive and gelation properties. DXA in situ gel-forming solution based on PLGA–PEG–PLGA copolymer of 20% (w/w) was prepared and evaluated for ocular pharmacokinetics in rabbit according to the microdialysis method, which was compared to the normal eye drop. Result: The copolymer with 20% (w/w) had a low critical solution temperature of 32°C, which is close to the surface temperature of the eye. The Cmax of DXA in the anterior chamber for the PLGA–PEG–PLGA solution was 125.2 μg/mL, which is sevenfold higher than that of the eye drop, along with greater area under the concentration–time curves (AUC). Conclusion: These results suggest that the PLGA–PEG–PLGA copolymer is potential thermosensitive in situ ge...

Mostafa A Shehata - One of the best experts on this subject based on the ideXlab platform.

  • spectrophotometric resolution of the severely overlapped spectra of clotrimazole with Dexamethasone in cream dosage form by mathematical manipulation steps
    Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2018
    Co-Authors: Hayam M Lotfy, Shereen M Tawakkol, Nesma Mahmoud Fahmy, Yasmin Mohammed Fayez, Mostafa A Shehata
    Abstract:

    Abstract Several spectrophotometric techniques were recently conducted for the determination of binary mixtures of clotrimazole (CLT) and Dexamethasone Acetate (DA) without any separation procedure. The methods were based on generation of ratio spectra of mixture then applying simple mathematic manipulation. The zero order absorption spectra of both drugs could be obtained by the constant center (CC) method. The concentration of both CLT and DA could be obtained by constant value via amplitude difference (CV-AD) method depending on ratio spectra, Ratio difference (RD) method where the difference between the amplitudes at two wavelengths (ΔP) on the ratio spectra could eliminate the contribution of the interfering substance and bring the concentration of the other, and the derivative ratio (DD1) method where the derivative of the ratio spectra was able to determine the drug of interest without any interference of the other one. While the concentration of DA could be measured after graphical manipulation as concentration using the novel advanced concentration value method (ACV). Calibration graphs were linear in the range of 75–550 μg/mL for CLT and 2–20 μg/mL for DA. The methods applied to the binary mixture under study were successfully applied for the simultaneous determination of the two drugs in synthetic mixtures and in their combined form Mycuten-D cream. The results obtained were compared statistically to each other and to the official methods.

  • validated stability indicating spectrophotometric methods for the determination of lidocaine hydrochloride calcium dobesilate and Dexamethasone Acetate in their dosage forms
    Analytical Chemistry Letters, 2013
    Co-Authors: Hayam M Lotfy, Shereen M Tawakkol, Nesma Mahmoud Fahmy, Mostafa A Shehata
    Abstract:

    AbstractSimple, specific, accurate and precise spectrophotometric methods were developed for determination of lidocaine hydrochloride, and calcium dobesilate in their binary mixture, or combined with Dexamethasone Acetate as a ternary mixture; in the presence of hydroquinone, the degradation product of calcium dobesilate without prior separation. In binary mixture lidocaine hydrochloride was determined using novel mathematical methods namely amplitude subtraction and amplitude factor, in addition to ratio subtraction coupled with first derivative. While dexamathasone Acetate was assayed by first derivative method. Lidocaine and Dexamethasone in ternary mixture could be determined by a novel resolution technique namely successive spectrophotometric resolution; including successive ratio subtraction coupled with either first derivative, or extended ratio subtraction for Dexamethasone and ratio subtraction coupled with first derivative for lidocaine hydrochloride; and finally the calcium dobesilate could be ...

Yuan Gao - One of the best experts on this subject based on the ideXlab platform.

  • plga peg plga hydrogel for ocular drug delivery of Dexamethasone Acetate
    Drug Development and Industrial Pharmacy, 2010
    Co-Authors: Yuan Gao, Yan Sun, Fuzheng Ren, Shen Gao
    Abstract:

    Aim: This study aims to investigate the suitability of thermosensitive triblock polymer poly-(dl-lactic acid-co-glycolic acid) (PLGA)–polyethylene glycol (PEG)–PLGA as a matrix material for ocular delivery of Dexamethasone Acetate (DXA). Methods: The copolymer was synthesized and evaluated for its thermosensitive and gelation properties. DXA in situ gel-forming solution based on PLGA–PEG–PLGA copolymer of 20% (w/w) was prepared and evaluated for ocular pharmacokinetics in rabbit according to the microdialysis method, which was compared to the normal eye drop. Result: The copolymer with 20% (w/w) had a low critical solution temperature of 32°C, which is close to the surface temperature of the eye. The Cmax of DXA in the anterior chamber for the PLGA–PEG–PLGA solution was 125.2 μg/mL, which is sevenfold higher than that of the eye drop, along with greater area under the concentration–time curves (AUC). Conclusion: These results suggest that the PLGA–PEG–PLGA copolymer is potential thermosensitive in situ ge...

I Ivanovic - One of the best experts on this subject based on the ideXlab platform.