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1.
Eur Rev Med Pharmacol Sci ; 28(6): 2351-2362, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38567598

RESUMO

OBJECTIVE: This work aimed to construct and validate a model for predicting distant metastasis (DM) in thyroid carcinoma (TC) patients aged≥50. PATIENTS AND METHODS: The research data were collected from the Surveillance, Epidemiology, and End Results (SEER) program databases via SEER*Stat software (https://seer.cancer.gov/). Logistics regression was used to screen the independent risk factors for TC patients. The nomogram was constructed and validated based on the logistics regression results for predicting DM occurrence in TC patients. Moreover, the characteristic curves (ROC) were used to assess the predictive performance. The decision analysis curve (DCA) and the calibration curve were used to test this nomogram's accuracy and discrimination. Additionally, we analyzed survival and risk scores in TC patients with metastasis using the Kaplan-Meier (KM) method. RESULTS: A total of 11,166 TC patients were divided into a training set and a validation set. The results showed that topography (T), lymph node metastasis (N), and (grade) G were crucial risk factors for predicting DM. ROC analysis showed that the model had a good discriminative ability both in the training and validation set. The DCA curve showed greater net benefits across a range of DM risks for the nomogram in the training and validation set. Survival analyses showed that the metastasis cases with low-risk scores have shown a poorer prognosis in this study, both in the training and validation set. CONCLUSIONS: The nomogram model had excellent predictive performance and net benefit for predicting DM of TC patients aged ≥50. The model can help doctors develop treatment plans for their patients.


Assuntos
Nomogramas , Neoplasias da Glândula Tireoide , Humanos , Metástase Linfática , Calibragem , Bases de Dados Factuais
3.
Zhonghua Bing Li Xue Za Zhi ; 51(5): 425-430, 2022 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-35511638

RESUMO

Objective: To investigate the clinicopathologic and molecular genetic characteristics, diagnosis, differential diagnosis, treatment and prognosis of histiocyte-rich rhabdomyoblastic tumor (HRRMT). Methods: The clinical data of two cases of HRRMT diagnosed in Fujian Provincial Hospital and Fujian University of Traditional Chinese Medicine Affiliated People's Hospital from 2020 to 2021 were collected. Histopathology and immunohistochemical (IHC) staining were used to assess morphological changes; the genetic changes were analyzed with next-generation sequencing. The relevant literature was reviewed. Results: Both cases showed well-defined solid nodules and soft masses. Microscopically, the tumors had a fibrous pseudocapsule with lymphocytic aggregation, and locally invaded the surrounding skeletal muscle tissue, and the tumor cells were fusiform to epithelioid with an intensive foamy histiocytic infiltrate. No necrosis or mitosis was observed. Immunophenotyping showed the tumor cells were positive for desmin, either one or both skeletal muscle markers (myogenin or MyoD1), and negative for h-caldesmon, ALK and SMA. The Ki-67 index was<5%. Using next-generation sequencing, one case was found to harbour KRAS (G12D) and MSH3 (Q470*) mutations. Conclusions: HRRMT is a newly described skeletal muscle tumor with uncertain malignant potential. Its diagnosis and differential diagnosis depend on morphologic and IHC staining. No specific molecular genetics changes have been identified so far.


Assuntos
Biomarcadores Tumorais , Neoplasias Musculares , Biomarcadores Tumorais/análise , Diagnóstico Diferencial , Histiócitos/patologia , Humanos , Biologia Molecular , Neoplasias Musculares/patologia , Prognóstico
4.
Lett Appl Microbiol ; 73(1): 54-63, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33765334

RESUMO

Lactic Acid Bacteria (LAB) regulate and maintain the stability of healthy microbial flora, inhibit the adhesion of pathogenic bacteria and promote the colonization of beneficial micro-organisms. The drug resistance and pathogenicity of Salmonella enteritis SE47 isolated from retail eggs were investigated. Meanwhile, Enterococcus faecalis L76 and Lactobacillus salivarius LAB35 were isolated from intestine of chicken. With SE47 as indicator bacteria, the diameters of L76 and LAB35 inhibition zones were 12 mm and 8·5 mm, respectively, by agar inhibition circle method, which indicated that both of them had inhibitory effect on Salmonella, and L76 had better antibacterial effect; two chicken-derived lactic acid bacteria isolates and Salmonella SE47 were incubated with Caco-2. The adhesion index of L76 was 17·5%, which was much higher than that of LAB35 (10·21%) and SE47 (4·89%), this experiment shows that the higher the bacteriostatic effect of potential probiotics, the stronger the adhesion ability; then Caco-2 cells were incubated with different bacteria, and the survival of Caco-2 cells was observed by flow cytometry. Compared with Salmonella SE47, the results showed that lactic acid bacteria isolates could effectively protect Caco-2 cells; finally, after different bacteria incubated Caco-2 cells, according to the cytokine detection kit, the RNA of Caco-2 cells was extracted and transcribed into cDNA, then detected by fluorescence quantitative PCR, the results showed that L76 could protect Caco-2 cells from the invasion of Salmonella SE47, with less cell membrane rupture and lower expression of MIF and TNF genes. Therefore, the lactic acid bacteria isolates can effectively inhibit the adhesion of Salmonella and protect the integrity of intestinal barrier.


Assuntos
Antibiose/fisiologia , Ovos/microbiologia , Lactobacillales/fisiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/fisiologia , Animais , Células CACO-2 , Galinhas/microbiologia , Farmacorresistência Bacteriana/fisiologia , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/fisiologia , Humanos , Ligilactobacillus salivarius/isolamento & purificação , Ligilactobacillus salivarius/fisiologia , Probióticos/isolamento & purificação , Probióticos/farmacologia , Salmonella enterica/patogenicidade
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 47(7): 554-560, 2019 Jul 24.
Artigo em Chinês | MEDLINE | ID: mdl-31365997

RESUMO

Objective: To investigate the role of piperine on the transformation of endothelial cells into fibroblasts. Methods: Cultured human umbilical vein endothelial cells (HUVECs, 4-6 passage) were used for the main experiments. The transformation models of endothelial cells into fibroblasts were induced by transforming growth factor ß (TGF-ß) stimulation. HUVECs were divided into 6 groups: control group, TGF-ß group and 4 groups treated with various concentrations of piperine (1, 5, 10, 20 µmol/L). CKK-8 was used to detect cell proliferation. The CD31/α-smooth muscle actin (α-SMA) expression level was detected by fluorescent staining. The vascular endothelial cadherin (VE-cadherin)/vimentin expression was detected by immunofluorescence staining. RT-PCR was used detect the mRNA expressions of transformation markers. Western blot was used to detect the protein expression of snail and twist. Results: TGF-ß increased HUVECs proliferation (P<0.05), which could be significantly inhibited by 10 and 20 µmol/L of piperine, but not by 1 and 5 µmol/L of piperine. Immunofluorescence results demonstrated that TGF-ß increased HUVECs transformation to fibroblasts as shown by downregulated expression of endothelial markers CD31, VE-cadherin, and upregulated expression of α-SMA and vimentin, again, these effects could be attenuated by 10 and 20 µmol/L piperine. The expression levels of collagen type Ⅰ and type Ⅲ were significantly higher in TGF-ß group than in control group (P<0.05), significantly lower in TGF-ß+10 µmol/L piperine group and TGF-ß+20 µmol/L piperine group than in TGF-ß group (P<0.05).In addition, RT-PCR results showed that TGF-ß increased mRNA expression of transformation markers (snail1, snail2, twist1, twist2), while 10 and 20 µmol/L of piperine could significantly downregulated the mRNA expressions of these markers. The protein expression levels of snail and twist were significantly higher in TGF-ß group than in control group (both P<0.05), which was significantly lower in TGF-ß+20 µmol/L piperine group than in TGF-ß group (both P<0.05). Conclusions: Piperine can inhibit the transformation of endothelial cells into fibroblasts. This effect might be viewed as one of the potential mechanisms of reduced myocardial fibrosis post piperine treatment.


Assuntos
Fibroblastos , Actinas , Alcaloides , Benzodioxóis , Células Cultivadas , Células Endoteliais , Humanos , Piperidinas , Alcamidas Poli-Insaturadas , Fator de Crescimento Transformador beta1
6.
Zhonghua Yan Ke Za Zhi ; 55(6): 413-418, 2019 Jun 11.
Artigo em Chinês | MEDLINE | ID: mdl-31189270

RESUMO

Objective: To evaluate the clinical effect of rigid permeable contact lenses (RGPCL) in the correction of irregular astigmatism after keratoplasty. Methods: Retrospective case study. From June 2012 to December 2016, 31 patients (37 eyes) who underwent corneal transplantation were tested and fitted with RGPCL. The patients' data of primary disease, interval from keratoplasty to contact lens fitting, uncorrected visual acuity, best spectacle-corrected visual acuity, best RGPCL-corrected visual acuity, contrast visual acuity before and after RGPCL wear, corneal topography and corneal endothelium parameters before and after RGPCL wear were collected, including ocular complications and comfort of contact lenses. Results: Among the 31 patients, 24 were male and 7 were female, with age of (31.3±5.8) years. The mean interval between grafting and initial contact lens fitting was (4.6±2.3) years. Uncorrected visual acuity, best spectacle-corrected visual acuity, and best RGPCL-corrected visual acuity were 0.81±0.21, 0.54±0.13, and 0.10±0.07, respectively (t=7.170, 16.617, 17.866; all P<0.05). The average astigmatism was -5.76±2.23 D and -0.83±0.47 D before and after wearing RGPCL (t=8.531, P<0.05). After wearing RGPCL, the contrast visual acuity of 100%, 25%, 10%, and 5% was increased from 0.95±0.33, 1.18±0.21, 1.40±0.00, and 1.40±0.00 to 0.12±0.15, 0.37±0.17, 0.65±0.25, and 0.96±0.29, respectively (t=5.972, 8.473, 9.243, 5.104; all P<0. 05). There were no obvious changes of corneal endothelium parameters during the observation period. No obvious corneal allograft rejection or other complications occurred, and 94.6% (35/37) of the patients felt comfortable with wearing RGPCL. Conclusions: RGPCL wear is safe and effective in correcting irregular astigmatism after corneal transplantation. We can obtain good corrected vision and improve contrast visual acuity, especially for patients who can not wear spectacles. (Chin J Ophthalmol, 2019, 55: 413-418).


Assuntos
Astigmatismo , Lentes de Contato , Transplante de Córnea , Topografia da Córnea , Feminino , Humanos , Masculino , Estudos Retrospectivos
7.
Sci Adv ; 5(5): eaau6459, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31058219

RESUMO

Topological semimetals are characterized by symmetry-protected band crossings, which can be preserved in different dimensions in momentum space, forming zero-dimensional nodal points, one-dimensional nodal lines, or even two-dimensional nodal surfaces. Materials harboring nodal points and nodal lines have been experimentally verified, whereas experimental evidence of nodal surfaces is still lacking. Here, using angle-resolved photoemission spectroscopy (ARPES), we reveal the coexistence of Dirac nodal surfaces and nodal lines in the bulk electronic structures of ZrSiS. As compared with previous ARPES studies on ZrSiS, we obtained pure bulk states, which enable us to extract unambiguously intrinsic information of the bulk nodal surfaces and nodal lines. Our results show that the nodal lines are the only feature near the Fermi level and constitute the whole Fermi surfaces. We not only prove that the low-energy quasiparticles in ZrSiS are contributed entirely by Dirac fermions but also experimentally realize the nodal surface in topological semimetals.

8.
Vet J ; 231: 1-7, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29429481

RESUMO

The aim of this study was to evaluate the effect of chitosanon the immune response induced by a DNA vaccine based on the ptfA gene of avian Pasteurella multocida. Naked DNA vaccine was packed with chitosanmolecules, resulting in a chitosannanoparticle DNA vaccine. The encapsulation efficiency, shape, size and resistance to DNA degradation were determined. The vaccine was administered to chickens and serum antibody, interferon-γ (IFN-γ), interleukin-2 (IL-2) and interleukin-4 (IL-4) concentrations were determined and lymphocyte proliferation assays were performed. After challenge with virulent avian P. multocida, protective efficacy was evaluated. The encapsulation efficiency of the chitosan nanoparticle DNA vaccine was 95.3%. The particle size was approximately 200nm and close to spherical in shape and it could effectively resist degradation by DNases. Following vaccination, serum antibodies, stimulation index (SI) value and concentrations of IFN-γ and IL-2 in chickens vaccinated with the chitosan nanoparticle DNA vaccine were significantly higher than those that were vaccinated with the naked DNA vaccine (P-values are 0.026, 0.045, 0.039 and 0.024, respectively). However, the concentrations of IL-4 in the two DNA vaccines group were no significant difference (P=0.157). The protective efficacy rate provided by naked DNA vaccine, chitosan nanoparticle DNA vaccine and the attenuated live vaccine were 56%, 68% and 88%, respectively. The results indicated that chitosan was able to enhance the immune response to a naked DNA vaccine based on the ptfA gene of P. multocida.


Assuntos
Vacinas Bacterianas/imunologia , Galinhas , Imunidade Humoral , Infecções por Pasteurella/veterinária , Pasteurella multocida/imunologia , Doenças das Aves Domésticas/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Animais , Quitosana/farmacologia , Imunidade Humoral/efeitos dos fármacos , Nanopartículas/química , Infecções por Pasteurella/imunologia , Infecções por Pasteurella/microbiologia , Infecções por Pasteurella/prevenção & controle , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Vacinas de DNA/imunologia
9.
Sci Rep ; 7(1): 6133, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28733663

RESUMO

Topological materials with exotic quantum properties are promising candidates for quantum spin electronics. Different classes of topological materials, including Weyl semimetal, topological superconductor, topological insulator and Axion insulator, etc., can be connected to each other via quantum phase transition. For example, it is believed that a trivial band insulator can be twisted into topological phase by increasing spin-orbital coupling or changing the parameters of crystal lattice. With the results of LDA calculation and measurement by angle-resolved photoemission spectroscopy (ARPES), we demonstrate in this work that the electronic structure of SrSn2As2 single crystal has the texture of band inversion near the critical point. The results indicate the possibility of realizing topological quantum phase transition in SrSn2As2 single crystal and obtaining different exotic quantum states.

10.
Nature ; 546(7660): 627-631, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28628922

RESUMO

In quantum field theory, Lorentz invariance leads to three types of fermion-Dirac, Weyl and Majorana. Although the existence of Weyl and Majorana fermions as elementary particles in high-energy physics is debated, all three types of fermion have been proposed to exist as low-energy, long-wavelength quasiparticle excitations in condensed-matter systems. The existence of Dirac and Weyl fermions in condensed-matter systems has been confirmed experimentally, and that of Majorana fermions is supported by various experiments. However, in condensed-matter systems, fermions in crystals are constrained by the symmetries of the 230 crystal space groups rather than by Lorentz invariance, giving rise to the possibility of finding other types of fermionic excitation that have no counterparts in high-energy physics. Here we use angle-resolved photoemission spectroscopy to demonstrate the existence of a triply degenerate point in the electronic structure of crystalline molybdenum phosphide. Quasiparticle excitations near a triply degenerate point are three-component fermions, beyond the conventional Dirac-Weyl-Majorana classification, which attributes Dirac and Weyl fermions to four- and two-fold degenerate points, respectively. We also observe pairs of Weyl points in the bulk electronic structure of the crystal that coexist with the three-component fermions. This material thus represents a platform for studying the interplay between different types of fermions. Our experimental discovery opens up a way of exploring the new physics of unconventional fermions in condensed-matter systems.

11.
Phys Rev Lett ; 117(12): 127204, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27689296

RESUMO

By combining angle-resolved photoemission spectroscopy and quantum oscillation measurements, we performed a comprehensive investigation on the electronic structure of LaSb, which exhibits near-quadratic extremely large magnetoresistance (XMR) without any sign of saturation at magnetic fields as high as 40 T. We clearly resolve one spherical and one intersecting-ellipsoidal hole Fermi surfaces (FSs) at the Brillouin zone (BZ) center Γ and one ellipsoidal electron FS at the BZ boundary X. The hole and electron carriers calculated from the enclosed FS volumes are perfectly compensated, and the carrier compensation is unaffected by temperature. We further reveal that LaSb is topologically trivial but shares many similarities with the Weyl semimetal TaAs family in the bulk electronic structure. Based on these results, we have examined the mechanisms that have been proposed so far to explain the near-quadratic XMR in semimetals.

12.
Nat Commun ; 7: 13148, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27748456

RESUMO

Crack formation is typically undesirable as it represents mechanical failure that compromises strength and integrity. Recently, there have also been numerous attempts to control crack formation in materials with the aim to prevent or isolate crack propagation. In this work, we utilize fragmentation, at submicron and nanometre scales, to create ordered metal oxide film coatings. We introduce a simple method to create modified films using electroplating on a prepatterned substrate. The modified films undergo preferential fragmentation at locations defined by the initial structures on the substrate, yielding ordered structures. In thicker films, some randomness in the characteristic sizes of the fragments is introduced due to competition between crack propagation and crack creation. The method presented allows patterning of metal oxide films over relatively large areas by controlling the fragmentation process. We demonstrate use of the method to fabricate high-performance electrochromic structures, yielding good coloration contrast and high coloration efficiency.

13.
Neoplasma ; 63(4): 559-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27268919

RESUMO

The objective of this study was to investigate the key genes and pathways associated with thyroid carcinoma. Based on the microarray data of GSE27155, we identified the differentially expressed genes (DEGs) between four types of thyroid carcinoma samples (papillary carcinoma (PTC), oncocytic carcinoma (OTC), follicular carcinoma (FTC) and anaplastic carcinoma (ATC)) and normal controls. With the obtained DEGs, we performed gene functional interaction (FI) network analysis. Then we conducted Venn diagram analysis to identify the intersection and specific DEGs of the four types of thyroid carcinomas. The intersections DEGs were performed by functional enrichment and transcription factor (TF) prediction analyses. These specific DEGs were performed by pathway enrichment analysis. There were respectively 323, 318, 118 and 1005 DEGs identified in PTC, OTC, FTC and ATC. Twelve sub-network modules were extracted based on gene FI network analysis and eight thyroid carcinoma-associated DEGs were involved in the network, such as TIMP1. Based on the Venn diagram analysis, 27 common DEGs were identified, such as HMGB3 which was regulated by TF of NKX3-1. There were 149 PTC-specific DEGs (like CLDN1), 160 OTC-specific DEGs, 94 FTC-specific DEGs (like PPARG), and 789 ATC-specific DEGs (like CDK1). They were enriched in some pathways, such as Cell cycle, Citrate cycle, and Oxidative phosphorylation. TIMP1, HMGB3, CLDN1, CDK1 and PPARG as well as pathways of Cell cycle, Citrate cycle, and Oxidative phosphorylation may play important roles in the progression of thyroid carcinoma.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Carcinoma Anaplásico da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Ontologia Genética , Redes Reguladoras de Genes/genética , Humanos , Transdução de Sinais/genética
14.
15.
Genet Mol Res ; 14(4): 12247-53, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26505373

RESUMO

The aim of this study was to investigate the protective effects of thymoquinone treatment on cholestatic rats with liver injury. Thirty-two Sprague-Dawley rats were divided randomly into four groups: normal control, bile duct ligation model control, low-dose thymoquinone (25 mg/kg), and high-dose thymoquinone (50 mg/kg). Thymoquinone gavage was administered continuously 3 days before bile duct ligation, and saline, at the same volume, was administered to the control group. The rats were sacrificed after 2 weeks of treatment, and the liver tissues were obtained and frozen. The contents of hydroxyproline (HP), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the homogenate of the liver tissues were determined to evaluate the changes in hepatic tissue pathology by fibrosis scoring. The HP and MDA levels were significantly lower and the SOD and GPx levels were significantly higher in the thymoquinone-treatment group than the corresponding levels in the model control group, and the differences were statistically significant (P < 0.05) and dose-dependent. The hepatic necrosis areas and hepatic fibrosis scores of the thymoquinone-treatment groups were significantly lower than those of the model group (P < 0.05). Thymoquinone increased the antioxidative capacity of liver and reduced the oxidative stress damage to the liver. Thymoquinone can be used as a liver protectant in patients with cholestasis.


Assuntos
Benzoquinonas/uso terapêutico , Colestase/tratamento farmacológico , Fígado/efeitos dos fármacos , Fígado/lesões , Animais , Benzoquinonas/farmacologia , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
16.
Genet Mol Res ; 13(3): 6350-5, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24782217

RESUMO

We aimed to investigate the association of inflammation-related genes such as IL-10, IL-6 and IL-1B with risk of ischemic stroke. We included 426 cases with ischemic stroke and 426 health controls from Xinxiang, China. Genomic DNA was extracted from the buffy coat layer of collected blood with the TIANamp blood DNA kit. Diabetes, hypertension, obesity, and smoking habits were associated with risk of ischemic stroke. We found that individuals carrying the CC genotype of IL-1B rs1864169 had a higher risk of ischemic stroke when compared with the TT genotype (OR = 1.80, 95%CI = 1.16-2.80). The IL-6 rs1800796 TT genotype was associated with increased risk of ischemic stroke. We found that IL-1B rs1864169 and IL-6 rs1800796 polymorphisms may interact with diabetes, hypertension and obesity. Our study suggests that IL-6 rs1800796 and IL-1B rs1864169 polymorphisms are associated with ischemic stroke risk in the Chinese population.


Assuntos
Isquemia Encefálica/genética , Interleucina-10/genética , Interleucina-1beta/genética , Interleucina-6/genética , Trombose Intracraniana/genética , Acidente Vascular Cerebral/genética , Adulto , Povo Asiático , Isquemia Encefálica/sangue , Isquemia Encefálica/etnologia , Isquemia Encefálica/patologia , Estudos de Casos e Controles , Diabetes Mellitus/fisiopatologia , Feminino , Genótipo , Humanos , Hipertensão/fisiopatologia , Interleucina-10/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Trombose Intracraniana/sangue , Trombose Intracraniana/etnologia , Trombose Intracraniana/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar/fisiopatologia , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/etnologia , Acidente Vascular Cerebral/patologia
17.
J Chromatogr A ; 1218(48): 8664-71, 2011 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-22035696

RESUMO

A simple and direct reversed-phase high performance liquid chromatography (RP-HPLC) method with UV detection was developed and validated for the determination of mono- and di-D-α-tocopherol polyethylene glycol 1000 succinate (TPGS 1000) in TPGS mixture. Before the HPLC analysis, mono- and di-TPGS 1000 were separated by simulated moving bed (SMB) chromatography system and characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The mass spectrometric results confirmed that the molar mass distribution of TPGS prepared in our laboratory was very close to that of the product of Eastman Chemical Company with similar n¯ (average polymerization degree), M(n)¯ (number-average molecular weight) and M(w)¯ (weight-average molecular weight). The HPLC analysis was carried out on a C30 analytical column with mobile phases comprised of acetonitrile (A) and isopropanol (B) in gradient conditions. Validation of the analytical method was done on the following parameters: system suitability, linearity, limits of detection and quantification, accuracy and precision, method robustness and solution stability. The linearity of the calibration curves for mono- and di-TPGS 1000 from both sources was found to be good (r(2)>0.9996). The recovery values were from 94.6% to 103.3% for mono-TPGS, and 93.5% to 103.3% for di-TPGS. This method could be successfully used in the direct quantification of mono- and di-TPGS in TPGS 1000 mixture using TPGS standards with similar molecular mass distributions although derived from different sources.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Vitamina E/análogos & derivados , Estabilidade de Medicamentos , Modelos Lineares , Polietilenoglicóis/análise , Polietilenoglicóis/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vitamina E/análise , Vitamina E/química
18.
Phytomedicine ; 18(8-9): 710-8, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21306883

RESUMO

The emergence of multidrug resistance (MDR) is a big challenge to cancer chemotherapy. Plant-derived agents have great potential to prevent onset or delay progression of the carcinogenic process, and enhance the efficacy of mainstream antitumor agents. In this study, fractionated extracts of Curcuma wenyujin and Chrysanthemum indicum were tested for their potential to modulate the MDR phenotype and function of P-gp in MCF-7/ADR and A549/Taxol cells in vitro. Fractions C. wenyujin C10, E10 from Curcuma wenyujin, and C. indicum E10 from Chrysanthemum indicum, exhibited significant effects in sensitization of these resistant cancer cells at non-toxic concentration to doxorubicin and docetaxel by MTT method. They also increased the intracellular doxorubicin accumulation and retention in MCF-7/ADR cells. In mechanism study, an increase of Rh123 accumulation and a decrease of Rh123 efflux were observed in MCF-7/ADR cells treated with these fractions, indicating a blockage of the activity of P-gp. Furthermore, C. wenyujin C10 had the ability to down-regulate the expression of P-gp. All these fractions could enhance the apoptosis induced by doxorubicin in MCF-7/ADR cells, and restore the effect of docetaxel on the induction of G2/M arrest in A549/Taxol cells. C. wenyujin C10 and E10 also owned the ability to induce S phase arrest. These results showed the therapeutic value of the three fractions as potential MDR-reversing agents and warranted further investigations.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Chrysanthemum/química , Curcuma/química , Extratos Vegetais/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Interações Medicamentosas , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Fase G2/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Medicina Tradicional Chinesa , Paclitaxel/farmacologia , Fitoterapia
19.
Phytomedicine ; 17(10): 794-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20541923

RESUMO

Radix Polygalae ("Yuan Zhi", the roots of Polygala tenuifolia Willd., YZ) is an important herb used in traditional Chinese medicine to mediate depression. The present study was designed to verify the antidepressant effects of the standardized YZ ethanol extract (YZE) and its four fractions YZ-30, YZ-50, YZ-70 and YZ-90 on the tail suspension (TST) and forced swimming test (FST). Furthermore, the standardization of the fractions obtained from the separation procedures was carried out by high-performance liquid chromatography (HPLC)-fingerprint. The YZ-50 fraction (Oligosaccharide esters--enriched, oral (200 mg/kg) showed a significant anti-immobility like effects. The data of YZ-50 on the corticosterone-induced injure of SH-SY5Y human neuroblastoma cell indicated that YZ-50 may have biological effects on neuroprotection. Proliferation of cell lines was assessed by dimethylthiazoldiphenyltetrazoliumbromide (MTT) and 5-bromo-2'-deoxyuridine (BrdU) incorporation assays. It was found that YZ-50 and its two bioactive compounds, 3,6'-di-o-sinapoyl-sucrose (DISS) and tenuifoliside A(TEA) showed protection activities in SY5Y cells from the lesion. By using bioassay-screening methods, our results indicate that the presence of oligosaccharide esters such as DISS and TEA in this herb may be responsible for the cytoprotective activity effects.


Assuntos
Antidepressivos/farmacologia , Medicamentos de Ervas Chinesas , Extratos Vegetais/farmacologia , Polygala/química , Animais , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Humanos , Camundongos , Camundongos Endogâmicos ICR
20.
Nat Prod Res ; 24(10): 915-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20496228

RESUMO

To investigate the chemical constituents from Incarvillea delavayi Bureau et Franchet, a new sesquiterpene, named delavayol, together with three known ones, was isolated by column chromatography. Spectroscopic and chemical evidence revealed the structures to be 8beta,9beta-dihydroxy-1(10)-eremophiliene-11,12-diol (1), oleanolic acid (2), myrianthic acid (3), and sitoindoside I (4). Compounds 3 and 4 were isolated from the genus Incarvillea for the first time.


Assuntos
Bignoniaceae/química , Sesquiterpenos/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Extratos Vegetais/química , Sesquiterpenos/isolamento & purificação
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