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1.
Int J Cancer ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31577838

RESUMO

Peritoneal metastasis is a critical feature and clinical challenge in epithelial ovarian cancer (EOC). We previously identified a novel long noncoding RNA (lncRNA, TC0101441) in epithelial ovarian cancer (EOC) using microarrays. However, the impact of TC0101441 on EOC metastasis and prognosis remains unclear. TC0101441 expression in EOC tissues and its correlation with clinicopathological factors and prognosis were examined. A series of in vitro and in vivo assays were performed to elucidate the roles and mechanism of TC0101441 in EOC metastasis. We found that TC0101441 levels were elevated in EOC tissues compared with those in normal controls and significantly correlated with an advanced clinical stage and lymph node metastasis. TC0101441 was determined to be an independent prognostic predictor of overall survival (OS) and disease-free survival (DFS). Furthermore, loss-of-function assays showed that TC0101441 promoted the invasive and metastatic capacities of EOC cells both in vitro and in vivo. Mechanistically, the prometastatic effects of TC0101441 were linked to the induction of epithelial-mesenchymal transition (EMT). Importantly, KiSS1 was identified as a downstream target gene of TC0101441 and was downregulated by TC0101441 in EOC cells. After TC0101441 was silenced, the corresponding phenotypes of EOC cell invasion and EMT were reversed by the overexpression of KiSS1. Taken together, our data suggest that TC0101441 functions as a potential promigratory/invasive oncogene by promoting EMT and metastasis in EOC through downregulation of KiSS1, which may represent a novel prognostic marker and therapeutic target in EOC. This article is protected by copyright. All rights reserved.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31269774

RESUMO

Hepatitis C remains a significant public health threat. However, the main routes of transmission have changed since the early 1990s. Currently, drug use is the main source of hepatitis C virus (HCV) infection, and some measures have been successively implemented and additional studies have been published. However, the factors correlating with HCV infection failed to clearly define. Our study pooled the odds ratios (ORs) with 95% confidence intervals (CIs) and analyzed sensitivity by searching data in the PubMed, Elsevier, Springer, Wiley, and EBSCO databases. Publication bias was determined by Egger's test. In our meta-analysis, HCV-infected and non-HCV-infected patients from 49 studies were analyzed. The pooled ORs with 95% CIs for study factors were as follows: Injecting drug use 10.11 (8.54, 11.97); sharing needles and syringes 2.24 (1.78, 2.83); duration of drug use >5 years 2.39 (1.54, 3.71); unemployment 1.50 (1.22, 1.85); commercial sexual behavior 1.00 (0.73, 1.38); married or cohabiting with a regular partner 0.88 (0.79, 0.98), and sexual behavior without a condom 1.72 (1.07, 2.78). This study found that drug users with histories of injecting drug use, sharing needles and syringes, drug use duration of >5 years, and unemployment, were at increased risk of HCV infection. Our findings indicate that sterile needles and syringes should be made available to ensure safe injection. In view of that, methadone maintenance treatment can reduce or put an end to risky drug-use behaviors, and should be scaled up further, thereby reducing HCV infection.

3.
J Zhejiang Univ Sci B ; 20(7): 563-575, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31168970

RESUMO

To explore the volatile profiles and the contents of ten bioactive components (polyphenols and caffeine) of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain, 17 samples of three tea varieties were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and high-performance liquid chromatography (HPLC). A total of 75 volatile components were tentatively identified. Laomaner (LME), Laobanzhang (LBZ), and other teas on Bulang Mountain (BL) contained 70, 53, and 71 volatile compounds, respectively. Among the volatile compounds, alcohols (30.2%-45.8%), hydrocarbons (13.7%-17.5%), and ketones (12.4%-23.4%) were qualitatively the most dominant volatile compounds in the different tea varieties. The average content of polyphenol was highest in LME (102.1 mg/g), followed by BL (98.7 mg/g) and LBZ (88.0 mg/g), while caffeine showed the opposite trend, 27.3 mg/g in LME, 33.5 mg/g in BL, and 38.1 mg/g in LBZ. Principal component analysis applied to both the volatile compounds and ten bioactive components showed a poor separation of samples according to varieties, while partial least squares-discriminant analysis (PLS-DA) showed satisfactory discrimination. Thirty-four volatile components and five bioactive compounds were selected as major discriminators (variable importance in projection (VIP) >1) among the tea varieties. These results suggest that chromatographic data combined with multivariate analysis could provide a useful technique to characterize and distinguish the sun-dried Pu-erh tea leaves from ancient tea varieties on Bulang Mountain.

4.
Reprod Sci ; : 1933719119831775, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808247

RESUMO

OBJECTIVE:: The transfer of long noncoding RNAs (lncRNAs) via exosomes to modulate recipient cells represents an important mechanism for disease progression. Antisense hypoxia-inducible factor (aHIF) is a well-known angiogenesis-related lncRNA. Here, we aimed to investigate the clinical implications of aHIF and exosomal aHIF in endometriosis and the involvement of exosome-shuttled aHIF in endometriosis angiogenesis. STUDY DESIGN:: The distribution and expression of aHIF in ectopic, eutopic, and normal endometria was evaluated. Serum exosomal aHIF levels in patients with endometriosis were tested. The correlation between serum exosomal aHIF and aHIF expression in ectopic endometria was analyzed. Endometriotic cyst stromal cells (ECSCs)-derived exosomes were characterized. The internalization of exosomes by human umbilical vein endothelial cells (HUVECs) was observed. A series of in vitro assays were conducted to investigate the roles and mechanisms of exosomal aHIF in endometriosis angiogenesis. RESULTS:: Clinically, aHIF was highly expressed in ectopic endometria and serum exosomes in patients with endometriosis. Serum exosomal aHIF was significantly correlated to aHIF expression in matched ectopic endometria. In vitro, PKH67-labeled exosomes derived from aHIF high expression ECSCs were effectively internalized by recipient HUVECs. Notably, exosome-shuttled aHIF was transferred from ECSCs to HUVECs, which in turn elicited proangiogenic behavior in HUVECs by activating vascular endothelial growth factor (VEGF)-A, VEGF-D, and basic fibroblast growth factor, thereby facilitating endometriosis angiogenesis. CONCLUSION:: Our study illustrates a potential cell-cell communication between ECSCs and HUVECs in an ectopic environment, provides a novel mechanistic model explaining how ECSCs induce angiogenesis from the perspective of the "exosomal transfer of aHIF," and highlights the clinical value of circulating exosomal aHIF in endometriosis.

5.
FASEB J ; 33(3): 4404-4417, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576233

RESUMO

Alzheimer's disease (AD) is a leading cause of dementia. However, the mechanisms responsible for development of AD, especially for the sporadic variant, are still not clear. In our previous study, we discovered that a small noncoding RNA (miR-188-3p) targeting ß-site amyloid precursor protein cleaving enzyme (BACE)-1, a key enzyme responsible for Aß formation, plays an important role in the development of neuropathology in AD. In the present study, we identified that miR-338-5p, a new miRNA that also targets BACE1, contributes to AD neuropathology. We observed that expression of miR-338-5p was significantly down-regulated in the hippocampus of patients with AD and 5XFAD transgenic (TG) mice, an animal model of AD. Overexpression of miR-338-5p in the hippocampus of TG mice reduced BACE1 expression, Aß formation, and neuroinflammation. Overexpression of miR-338-5p functionally prevented impairments in long-term synaptic plasticity, learning ability, and memory retention in TG mice. In addition, we provide evidence that down-regulated expression of miR-338-5p in AD is regulated through the NF-κB signaling pathway. Our results suggest that down-regulated expression of miR-338-5p plays an important role in the development of AD.-Qian, Q., Zhang, J., He, F.-P., Bao, W.-X., Zheng, T.-T., Zhou, D.-M., Pan, H.-Y., Zhang, H., Zhang, X.-Q., He, X., Sun, B.-G., Luo, B.-Y., Chen, C., Peng, G.-P. Down-regulated expression of microRNA-338-5p contributes to neuropathology in Alzheimer's disease.

6.
Int J Biol Sci ; 14(14): 1960-1973, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30585260

RESUMO

Exosomes mediate cell-cell crosstalk in cancer progression by transferring their molecular cargos, including long noncoding RNAs (lncRNAs). Metastasis­associated lung adenocarcinoma transcript 1 (MALAT1) is a well-known lncRNA associated with cancer angiogenesis and metastasis. However, the presence of MALAT1 in exosomes and the roles and clinical values of exosomal MALAT1 in epithelial ovarian cancer (EOC) remain unknown. The present study focused on the crosstalk between EOC cells and endothelial cells mediated by exosomal MALAT1 and aimed to explore the roles of exosomes and exosomal MALAT1 in EOC angiogenesis and to reveal the clinical relevance and prognostic predictive value of serum exosomal MALAT1 in EOC. We observed that MALAT1 was increased in both metastatic EOC cells and their secreted exosomes. Exosomal MALAT1 derived from EOC cells was transferred to recipient human umbilical vein endothelial cells (HUVECs) via exosomes. In vitro and in vivo experiments demonstrated that MALAT1 knockdown impaired the exosome-mediated proangiogenic activity of HUVECs through certain key angiogenesis-related genes. Clinically, elevated serum exosomal MALAT1 was highly correlated with an advanced and metastatic phenotype of EOC and was an independent predictive factor for EOC overall survival (OS). Moreover, a prognostic nomogram model we constructed showed a good prediction of the probability of 3-year OS of EOC patients according to the c-index (0.751, 95% confidence interval [CI]=0.691-0.811) and calibration curve. Collectively, our data provide a novel mechanism by which EOC cells transfer MALAT1 via exosomes to recipient HUVECs and influence HUVECs by stimulating angiogenesis-related gene expression, eventually promoting angiogenesis. Additionally, circulating exosomal MALAT1 can serve as a promising serum-based, noninvasive predictive biomarker for EOC prognosis.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Exossomos/metabolismo , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/metabolismo , Adenocarcinoma de Pulmão/genética , Animais , Western Blotting , Exossomos/genética , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Transmissão , Análise Multivariada , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , RNA Longo não Codificante/genética , Reação em Cadeia da Polimerase em Tempo Real
7.
Oxid Med Cell Longev ; 2018: 8549052, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849919

RESUMO

To protect against oxidative stress-induced apoptosis in lens epithelial cells is a potential strategy in preventing cataract formation. The present study aimed at studying the protective effect and underlying mechanisms of p-coumaric acid (p-CA) on hydrogen peroxide- (H2O2-) induced apoptosis in human lens epithelial (HLE) cells (SRA 01-04). Cells were pretreated with p-CA at a concentration of 3, 10, and 30 µM before the treatment of H2O2 (275 µM). Results showed that pretreatment with p-CA significantly protected against H2O2-induced cell death in a dose-dependent manner, as well as downregulating the expressions of both cleaved caspase-3 and cleaved caspase-9 in HLE cells. Moreover, p-CA also greatly suppressed H2O2-induced intracellular ROS production and mitochondrial membrane potential loss and elevated the activities of T-SOD, CAT, and GSH-Px of H2O2-treated cells. As well, in vitro study showed that p-CA also suppressed H2O2-induced phosphorylation of p-38, ERK, and JNK in HLE cells. These findings demonstrate that p-CA suppresses H2O2-induced HLE cell apoptosis through modulating MAPK signaling pathways and suggest that p-CA has a potential therapeutic role in the prevention of cataract.


Assuntos
Apoptose/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Propionatos/farmacologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Catalase/metabolismo , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Cristalino/citologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Propionatos/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(1): 8-12, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29737081

RESUMO

OBJECTIVE: To investigate the effects of pomegranate leaves extract(PLE)on proliferation,apoptosis and metastasis of prostate cancer cells. METHODS: The proliferation of TRAMP-C1,DU145,PC3 prostate cancer cells treated with different concentrations of PLE (final mass concentrations were 12.5,25,50,100, 200 µg/mL,respectively) for different time (24,48,72 h) was detected by MTT assay. Colony formation assay was performed to verify the long-term effects of PLE on the proliferation of DU145 and PC3 cells.After being treated with PLE for 48 h,Hoechst-33258 staining was used to observe the changes in the nucleus,the cell apoptotic rate was detected by flow cytometry,and wound-healing migration assay was perform to test the change of migration. RESULTS: In comparison with the control group,PLE in the range of 12.5-200 µg/mL had a certain inhibitory effect on the proliferation of TRAMP-C1,DU145 and PC3 cells ( P<0.05).In the range of 6.25-100 µg/mL,the number of colony formation of DU145 and PC3 was significantly reduced( P<0.01).After PLE treated for 48 h, the apoptotic features of nuclear fragmentation and the formation apoptotic body was observed in PC3. With the increase of concentration,the apoptotic rate increased gradually ( P<0.05),and the ability of cells to migrate to the scratch area was significantly weaker than the control group ( P<0.01). CONCLUSION: PLE has effect on proliferation,apoptosis and metastasis of prostate cancer cells.

9.
J Theor Biol ; 443: 82-91, 2018 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-29355543

RESUMO

In this paper, a mathematical model describing the transmission of two-strain Dengue virus between mosquitoes and humans, incorporating vector control and awareness of susceptible humans, is proposed. By using the next generation matrix method, we obtain the threshold values to identify the existence and stability of three equilibria states, that is, a disease-free state, a state where only one serotype is present and another state where both serotypes coexist. Further, explicit conditions determining the persistence of this disease are also obtained. In addition, we investigate the sensitivity analysis of threshold conditions and the optimal control strategy for this disease. Theoretical results and numerical simulations suggest that the measures of enhancing awareness of the infected and susceptible human self-protection should be taken and the mosquito control measure is necessary in order to prevent the transmission of Dengue virus from mosquitoes to humans.

10.
Int J Oncol ; 51(2): 507-514, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28714515

RESUMO

Previously, the novel oestrogen (E2)-upregulated lncRNA TC0101441, was identified by us, via microarray analysis. However, the detailed mechanism by which E2 upregulates TC0101441 and the role of TC0101441 in epithelial ovarian cancer (EOC) progression have not been elucidated. In the present study, we further analysed TC0101441, which we designated oestrogen-induced long non-coding RNA-1 (ElncRNA1). We showed that E2 transcriptionally upregulates ElncRNA1 through the oestrogen receptor α (ERα)-oestrogen response element (ERE) pathway using RNA stability assays, bioinformatics-based searches for ERE binding sites, chromatin immunoprecipitation (ChIP) assays and dual luciferase reporter assays. Clinically, ElncRNA1 levels are significantly higher in EOC tissues than in normal ovarian surface epithelium. In vitro and in vivo loss-of-function assays revealed that ElncRNA1 promotes EOC cell proliferation. This pro-proliferation effect of ElncRNA1 was partially mediated by the regulation of CDK4, CDK6 and cyclin D1. These findings provide the first evidence that E2 upregulates ElncRNA1 at the transcriptional level through the ERα-ERE pathway and that this novel E2-upregulated lncRNA has an oncogenic role in EOC growth. The placement of ElncRNA1 in the E2-ERα-ERE signalling pathway may provide greater insight into the effects of oestrogen on EOC progression from the perspective of lncRNA.


Assuntos
Receptor alfa de Estrogênio/genética , Estrogênios/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , Regulação para Cima , Animais , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Estabilidade de RNA , RNA Longo não Codificante/química
11.
Biosens Bioelectron ; 89(Pt 2): 937-945, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27818049

RESUMO

Quantifying the glycan expression status on cell surfaces is of vital importance for insight into the glycan function in biological processes and related diseases. Here we developed a versatile aptasensor for electrochemical quantification of cell surface glycan by taking advantage of the cell-specific aptamer, and the lectin-functionalized gold nanoparticles acting as both a glycan recognition unit and a signal amplification probe. To construct the aptasensor, amine-functionalized mucin 1 protein (MUC1) aptamer was first covalently conjugated to carboxylated-magnetic beads (MBs) using the succinimide coupling (EDC-NHS) method. On the basis of the specific recognition between aptamer and MUC1 protein that overexpressed on the surface of MCF-7 cells, the aptamer conjugated MBs showed a predominant capability for cell capture with high selectivity. Moreover, a lectin-based nanoprobe was designed by noncovalent assembly of concanavalin A (ConA) on gold nanoparticles (AuNPs). This nanoprobe incorporated the abilities of both the specific carbohydrate recognition and the signal amplification based on the gold-promoted reduction of silver ions. By coupling with electrochemical stripping analysis, the proposed sandwich-type cytosensor showed an excellent analytical performance for the ultrasensitive detection of MCF-7 cells and quantification of cell surface glycan. More importantly, taking advantage of Con A-gold nanoprobe catalyzed silver enhancement, the proposed method was further used for naked-eye tracking glycolytic inhibition in living cells. This aptasensor holds great promise as a new point-of-care diagnostic tool for analyzing glycan expression on living cells and further helps cancer diagnosis and treatment.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Mucina-1/química , Polissacarídeos/isolamento & purificação , Concanavalina A/química , Humanos , Limite de Detecção , Células MCF-7 , Nanopartículas Metálicas , Polissacarídeos/química , Succinimidas/química
12.
Chin Med J (Engl) ; 129(21): 2530-2534, 2016 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-27779157

RESUMO

BACKGROUND: High-dose methotrexate (HD-MTX) with folinic acid (leucovorin) rescue is "gold standard" therapy for osteosarcoma. Plasma concentrations of methotrexate (MTX) are closely related to its efficacy and toxicity. Delayed excretion of MTX can lead to serious adverse reactions that may result in treatment cessation, irreversible organ damage, and death. This study focused on the incidence of delayed excretion of MTX in Chinese osteosarcoma patients. METHODS: A total of 1277 osteosarcoma patients were treated with HD-MTX chemotherapy (4291 cycles) from 2010 to 2015. Factors that could influence delayed excretion of MTX (gender, age, number of chemotherapy cycles, and serum concentration of MTX) were analyzed. RESULTS: The incidence of delayed excretion of MTX (serum concentrations at 24 h [C24 h] >5 µmol/L) and severe delayed excretion of MTX (C24 h >20 µmol/L) were 6.19% and 0.86% per patient, and 2.31% and 0.26% per cycle of treatment, respectively. The incidence of severe delayed excretion of MTX was associated with gender, age, and C24 h. CONCLUSIONS: Precaution of delayed excretion of MTX is needed during osteosarcoma treatment using HD-MTX. An optimal individualized rescue strategy can be created with consideration of gender, age, and C24 h.


Assuntos
Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Osteossarcoma/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Criança , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Masculino , Metotrexato/farmacocinética , Osteossarcoma/sangue , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
13.
Org Biomol Chem ; 13(4): 1159-68, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25428174

RESUMO

Here a new method to determine the oligomeric state and orientation of coiled-coil peptide motifs is described. Peptides K and E, which are designed to form a parallel heterodimeric complex in aqueous solution, were labeled with the aromatic amino acids tryptophan and tyrosine on the C-terminus respectively as 'fingerprint' residues. One of the peptides was also labeled with the paramagnetic probe MTSL. One dimensional proton NMR spectroscopy was used to study the peptide quaternary structure by monitoring the signal suppression of the aromatic labels due to proximity of the nitroxyl radical. 1D-NMR confirmed that the peptides K and E form a heterodimeric coiled coil with a parallel orientation. In addition, fluorescence emission quenching of the aromatic labels due to electron exchange with a nitroxyl radical confirmed the parallel coiled coil orientation. Thus, paramagnetic nitroxide and aromatic fluorophore labeling of peptides yields valuable information regarding the quaternary structure from 1D-NMR and steady-state fluorescence measurements. This convenient method is useful not only to investigate coiled coil assembly, but can also be applied to any defined supramolecular assembly.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Peptídeos/química , Sequência de Aminoácidos , Dimerização , Dados de Sequência Molecular , Óxidos de Nitrogênio/química , Estrutura Secundária de Proteína
14.
Chem Cent J ; 6(1): 26, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22472205

RESUMO

BACKGROUND: Due to the extensive use of phosphates in industry, agriculture and households, the phosphate - γ-alumina interactions are important for understanding its detrimental contribution to eutrophication in lakes and rivers. In situ Fourier transform infrared (FTIR) spectroscopy can provide more detailed information on the adsorbate-adsorbent interaction and the formation of hydrogen bonds. RESULTS: In situ ATR-FTIR spectroscopy was used to identify phosphate complexes adsorbed within the three-dimensional network of mesoporous γ-alumina at pH 4.1 and 9.0. The integrated intensity between 850 cm-1 and 1250 cm-1 was used as a relative measure of the amount of adsorbed phosphate. The integrated intensity proved to be about 3 times higher at pH 4.1 as compared with the corresponding intensity at pH 9.0. The adsorption of phosphate at the two pH conditions could be well described by the Langmuir adsorption isotherm at low concentrations and the empirical Freundlich adsorption isotherm for the whole concentration range, viz. 5 - 2000 µM. CONCLUSIONS: From the band shape of infrared spectra at pH 4.1 and pH 9.0, it was proposed that the symmetry of the inner-sphere surface complex formed between phosphate and γ-alumina was C1 at the lower pH value, whilst the higher value (9.0) implied a surface complex with C2v or C1 symmetry. The difference in adsorbed amount of phosphate at the two pH values was ascribed to the reduced fraction of ≡ AlOH2+ surface sites and the increased fraction of ≡ AlO- sites upon increasing pH from 4 to 9.

15.
Analyst ; 137(6): 1316-8, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22143244

RESUMO

An electrochemical, label-free method was developed to detect folate receptor positive tumor cells by specific recognition of a polydopamine-coated carbon nanotubes-folate nanoprobe to cell-surface folate receptors. This strategy offers great promise to extend its application in studying the interaction of ligand and cell-surface receptor.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Receptores de Folato com Âncoras de GPI/química , Nanotubos de Carbono/química , Neoplasias/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Linhagem Celular Tumoral , Receptores de Folato com Âncoras de GPI/metabolismo , Humanos , Teste de Materiais , Neoplasias/patologia
16.
World J Gastroenterol ; 17(39): 4389-95, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22110264

RESUMO

AIM: To investigate the anti-tumor effects of Paris chinensis dioscin (PCD) and mechanisms regarding cell cycle regulation and apoptosis in human gastric cancer SGC-7901 cells. METHODS: Cell viability was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Cell apoptosis was evaluated by flow cytometry and laser scanning confocal microscope (LSCM) using Annexin-V/propidium iodide (PI) staining, and the cell cycle was evaluated using PI staining with flow cytometry. Intracellular calcium ions were detected under fluorescence microscope. The expression of cell cycle and apoptosis-related proteins cyclin B1, CDK1, cytochrome C and caspase-3 was measured by immunohistochemical staining. RESULTS: PCD had an anti-proliferation effect on human gastric cancer SGC-7901 cells in a dose- and time-dependent manner. After treatment of SGC-7901 cells with PCD, apoptosis appeared in SGC-7901 cells. Morphological changes typical of apoptosis were also observed with LSCM by Annexin V/PI staining, and the cell number of the G0/G1 phase was decreased, while the number of cells in the G2/M phase was increased. Cell cycle-related proteins, such as cyclin B1 and CDK1, were all down-regulated, but caspase-3 and cytochrome C were up-regulated. Moreover, intracellular calcium accumulation occurred in PCD-treated cells. CONCLUSION: G2/M phase arrest and apoptosis induced by PCD are associated with the inhibition of CDK-activating kinase activity and the activation of Ca(2+)-related mitochondrion pathway in SGC-7901 cells.


Assuntos
Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Diosgenina/análogos & derivados , Fase G2/efeitos dos fármacos , Neoplasias Gástricas/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diosgenina/farmacologia , Humanos , Liliaceae/química , Extratos Vegetais/farmacologia
17.
Anal Chem ; 83(20): 7902-9, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21888423

RESUMO

The ability for early evaluation of therapeutic effects is a significant challenge in leukemia research. To address this challenge, we developed a novel electrochemical platform for ultrasensitive and selective detection of apoptotic cells in response to therapy. In order to construct the platform, a novel three-dimensional (3-D) architecture was initially fabricated after combining nitrogen-doped carbon nanotubes and gold nanoparticles via a layer-by-layer method. The formed architecture provided an effective matrix for annexin V with high stability and bioactivity to enhance sensitivity. On the basis of the specific recognition between annexin V and phosphatidylserine on the apoptotic cell membrane, the annexin V/3-D architecture interface showed a predominant capability for apoptotic cell capture. Moreover, a lectin-based nanoprobe was designed by noncovalent assembly of concanavalin A on CdTe quantum dots (QDs)-labeled silica nanospheres with poly(allylamine hydrochloride) as a linker. This nanoprobe incorporated both the specific carbohydrate recognition and the multilabeled QDs-based signal amplification. By coupling with the QDs-based nanoprobe and electrochemical stripping analysis, the proposed sandwich-type cytosensor showed an excellent analytical performance for the ultrasensitive detection of apoptotic cells (as low as 48 cells), revealing great potential toward the early evaluation of therapeutic effects.


Assuntos
Apoptose , Técnicas Eletroquímicas , Anexina A5/metabolismo , Compostos de Cádmio/química , Linhagem Celular Tumoral , Concanavalina A/química , Eletrodos , Citometria de Fluxo , Humanos , Fosfatidilserinas/metabolismo , Poliaminas/química , Pontos Quânticos , Dióxido de Silício/química , Telúrio/química
18.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1624, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21837030

RESUMO

In the hydrazone molecule of the title compound, C(13)H(9)I(2)N(3)O(2)·CH(3)CN, the aromatic rings form a dihedral angle of 9.4 (3)°. In the crystal structure, inter-molecular I⋯N inter-actions [3.099 (4) Å] link hydrogen-bonded aggregates of the hydrozone and solvent molecules related by translation along the b axis into chains. An intramolecular O-H⋯N hydrogen bond forms an S(6) ring.

19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): o964, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754227

RESUMO

In the title compound, C(19)H(16)N(2)O(2), the benzene ring and the naphthyl ring system form a dihedral angle of 8.7 (3)° and an intra-molecular O-H⋯N hydrogen bond generates an S(6) ring. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming C(4) chains propagating in [001].

20.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): o965, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754228

RESUMO

In the title compound, C(19)H(16)N(2)O(2), the benzene ring and naphthyl ring system are inclined at a dihedral angle of 16.1 (3)°. An intra-molecular O-H⋯N hydrogen bond influences the mol-ecular conformation. In the crystal, mol-ecules are linked through N-H⋯O hydrogen bonds into chains running along the a axis.

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