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1.
FASEB J ; 34(8): 10860-10870, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32592239

RESUMO

The tumor microenvironment (TME) is a crucial factor in cancer progression. In breast cancer, cancer-associated fibroblasts (CAFs) and the derived stromal components have been recognized as comprising the majority of the pathological structure of the TME. In this study, we show that metformin (Met), a diabetes drug, transforms CAFs in the TME. Met disrupts tumor-stromal cross talk by preventing breast cancer cell transforming growth factor-ß (TGF-ß) signaling and the production of stromal-derived factor-1 (SDF-1) and interleukin-8 (IL-8) by CAFs. The suppression of bidirectional signaling between tumor cells and CAFs by Met is attributed to increased phospho-AMP kinase (p-AMPK) levels. By upregulating p-AMPK in CAFs, Met induces prolyl hydroxylases (PHDs), leading to the degradation of hypoxia-inducible factor-1α (HIF-1α) in CAFs. Moreover, interruption of HIF-1α-driven SDF-1 signaling in CAFs by Met leads to decreased breast cancer cell invasion. These findings suggest that Met may be used to target tumor-promoting signaling between CAFs and breast cancer cells in the TME.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metformina/farmacologia , Adenilato Quinase/metabolismo , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Interleucina-8/metabolismo , Células MCF-7 , Invasividade Neoplásica/patologia , Prolil Hidroxilases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
2.
Biomacromolecules ; 22(8): 3590-3600, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34286578

RESUMO

One of the biggest challenges of the protein delivery system is to realize stable and high protein encapsulation efficiency in blood circulation and rapid release of protein in the targeted tumor cells. To overcome these hurdles, we fabricated enzyme-responsive photo-cross-linked nanogels (EPNGs) through UV-triggered chemical cross-linking of cinnamyloxy groups in the side chain of PEGylation hyaluronic acid (HA) for CD44-targeted transport of cytochrome c (CC). The EPNGs showed high loading efficiency and excellent stability in different biological media. Notably, CC leakage effectively suppressed under physiological conditions but accelerated release in the presence of hyaluronidase, an overexpressed enzyme in tumor cells. Moreover, thiazolylblue tetrazolium bromide (MTT) results indicated that the vacant EPNGs showed excellent nontoxicity, while CC-loaded EPNGs exhibited higher killing efficiency to CD44-positive A549 cells than to CD44-negative HepG2 cells and free CC. Confocal images confirmed that CC-loaded EPNGs could effectively be internalized by CD44-mediated endocytosis pathway and rapidly escape from the endo/lysosomal compartment. Human lung tumor-bearing mice imaging assays further revealed that CC-loaded EPNGs actively target tumor locations. Remarkably, CC-loaded EPNGs also exhibited enhanced antitumor activity with negligible systemic toxicity. These results implied that these EPNGs have appeared as stable and promising nanocarriers for tumor-targeting protein delivery.


Assuntos
Nanopartículas , Células A549 , Animais , Linhagem Celular Tumoral , Humanos , Ácido Hialurônico , Camundongos , Nanogéis
3.
J Obstet Gynaecol Res ; 39(3): 746-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23106919

RESUMO

Ewing sarcomas/peripheral primitive neuroectodermal tumors (ES/pPNET) are extremely rare in the vulva. A review of the literature reveals only 14 previously reported possible cases. Here we reported a case of primary extraskeletal Ewing's sarcoma (EES) of the vulva in a 37-year-old woman. Characteristic histologic features of ES/pPNET were present in this case, including a monomorphic population of small round blue cells with cytoplasmic glycogen confirmed by periodic acid-Schiff, membrane staining with CD99 and nuclear staining with FLI-1. After surgery, the patient was found to have pulmonary metastasis and then received six cycles of polychemotherapy. She is still alive with stable disease after 1 year of follow up. Our findings underline the crucial role of immunohistochemical techniques in the differential diagnosis of small round cell tumors in these unusual locations. We also give a summary about the clinical and pathological features of the primary ES/pPNET in the vulva reported previously in the literature.


Assuntos
Sarcoma de Ewing/patologia , Vulva/patologia , Neoplasias Vulvares/patologia , Adulto , Feminino , Humanos , Tumores Neuroectodérmicos Primitivos Periféricos/patologia
4.
Cell Death Dis ; 13(8): 751, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042202

RESUMO

There is a potential correlation between G-protein-coupled receptor-associated sorting protein 1 (GASP1) and breast tumorigenesis. However, its biological function and underlying molecular mechanism in breast cancer have not been clearly delineated. Here, we demonstrated that GASP1 was highly expressed in breast cancers, and patients harboring altered GASP1 showed a worse prognosis than those with wild-type GASP1. Functional studies showed that GASP1 knockout significantly suppressed malignant properties of breast cancer cells, such as inhibition of cell proliferation, colony formation, migration, invasion and xenograft tumor growth in nude mice as well as induction of G1-phase cell cycle arrest, and vice versa. Mechanistically, GASP1 inhibited proteasomal degradation of insulin-like growth factor 1 receptor (IGF1R) by competitively binding to IGF1R with ubiquitin E3 ligase MDM2, thereby activating its downstream signaling pathways such as NF-κB, PI3K/AKT, and MAPK/ERK pathways given their critical roles in breast tumorigenesis and progression. IGF1, in turn, stimulated GASP1 expression by activating the PI3K/AKT pathway, forming a vicious cycle propelling the malignant progression of breast cancer. Besides, we found that GASP1 knockout obviously improved the response of breast cancer cells to paclitaxel. Collectively, this study demonstrates that GASP1 enhances malignant behaviors of breast cancer cells and decreases their cellular response to paclitaxel by interacting with and stabilizing IGF1R, and suggests that it may serve as a valuable prognostic factor and potential therapeutic target in breast cancer.


Assuntos
Neoplasias da Mama , Fator de Crescimento Insulin-Like I , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Nus , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais
5.
Breast ; 60: 287-294, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34844175

RESUMO

BACKGROUND: Radiotherapy after breast-conserving surgery (BCS) is not always necessary in older women staged T1N0M0 with low-risk invasive breast cancer, but few studies have concluded the detailed tumor size as a reference for avoiding radiotherapy. The study was conducted to explore and identify the optimal cutoff tumor size. METHODS: The study population was from the Surveillance, Epidemiology, and End Results (SEER) database in 2010-2016. Propensity score matching was used to balance the confounders between groups. Predictors associated with survival were analyzed by Kaplan-Meier, X-tile, Cox proportional hazards model and competing risk model. RESULTS: A total of 52049 women and 3846 deaths were included in the cohort with a median follow-up of 34 months. Based on the cutoff value determined by X-tile analysis, the study population were divided into small tumor group (≤14 mm in diameter) and large tumor group (>14 mm in diameter). Small tumors and radiotherapy were correlated with better breast cancer-specific survival (BCSS). In subgroup analysis, the absolute benefit of BCSS in 6 years attributed to radiotherapy was only 0.90% (RT vs. non- RT:98.77% vs. 97.87%) for patients with small tumors but up to 3.33% (RT vs. non- RT:97.10% vs. 93.77%) for those with large tumors. CONCLUSION: Small tumors and adjuvant radiotherapy were associated with improved long-term prognosis, and 14 mm in diameter was the cutoff tumor size of omitting radiotherapy for patients aged 65 or older with T1N0M0 stage, ER+ and HER2-breast carcinoma after BCS.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Idoso , Mama/patologia , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Estadiamento de Neoplasias , Radioterapia Adjuvante , Programa de SEER
6.
J Vis Exp ; (159)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32420992

RESUMO

Stereotaxic injection has been widely used for direct delivery of compounds or viruses to targeted brain areas in rodents. Direct targeting of serotonergic neurons in the dorsal raphe nucleus (DRN) can cause excessive bleeding and animal death, due to its location below the superior sagittal sinus (SSS). This protocol describes the generation of a DRN serotonergic neuron-lesioned mouse model (>90% survival rate) with stable loss of >70% 5-HT-positive cells in the DRN. The lesion is induced by stereotaxic injection of a selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) into the DRN using an angled approach (30° in the anterior/posterior direction) to avoid injury to the SSS. DRN serotonergic neuron-lesioned mice display anxiety-associated behavior alterations, which helps to confirm success of the DRN lesion surgery. This method is used here for DRN lesions, but it can also be used for other stereotaxic injections that require angular injections to avoid midline structures. This DRN serotonergic neuron-lesioned mouse model provides a valuable tool for understanding the role of serotonergic neurons in the pathogenesis of psychiatric disorders, such as generalized anxiety disorder and major depressive disorder.


Assuntos
5,7-Di-Hidroxitriptamina/administração & dosagem , Núcleo Dorsal da Rafe/efeitos dos fármacos , Neurônios Serotoninérgicos/fisiologia , Técnicas Estereotáxicas , 5,7-Di-Hidroxitriptamina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL
7.
Int J Radiat Oncol Biol Phys ; 107(3): 499-511, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32179132

RESUMO

PURPOSE: To evaluate the effect of hyperthermia combined with concurrent radiochemotherapy (RCT) and treatment-related toxicity in patients with cervical cancer (CC) stage IB-IV. METHODS AND MATERIALS: This study was conducted between 2009 and 2013 in patients with International Federation of Gynecology and Obstetrics (FIGO) stage IB-IV CC. The patients were randomly assigned into 2 treatment groups: RCT and RCT plus hyperthermia (RCHT). Five-year survival, treatment-related toxicity, and other prognostic factors were evaluated. RESULTS: Three hundred seventy-three patients completed treatment and were analyzed by per-protocol (PP) analysis. The 5-year overall survival (OS) in the RCHT group (81.9%) was better than that in RCT group (72.3%), and the log-rank test showed a statistically significant difference between the 2 groups (P = .040). Univariate and multivariate Cox regression analysis for 5-year OS showed a statistically significant difference (P = .043, P = .045, respectively). The 5-year local relapse-free survival in RCHT (86.8%) was also better than that in RCT (82.7%), but the difference was not significant. Acute or late toxicity was not significantly different between the 2 groups. Advanced clinical stage (FIGO) and larger tumor size showed higher risk of death and a relatively poor prognosis in univariate and multivariate analysis. CONCLUSIONS: The study confirmed that hyperthermia combined with RCT yielded a better 5-year OS in CC. Acute and late toxicity was similar between the RCT and RCHT groups. Clinical stage (FIGO) and tumor size were independent prognostic factors in CC.


Assuntos
Quimiorradioterapia , Hipertermia Induzida , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Sobrevida , Neoplasias do Colo do Útero/patologia
8.
Onco Targets Ther ; 12: 3919-3931, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213826

RESUMO

Background: Breast cancer is one of the foremost threats to female health nowadays. Tamoxifen, an antagonist of estrogen receptor-α (ERα), is the first choice for endocrine-dependent breast cancer (ERα-positive breast cancer) treatment. However, ERα has an important function in the normal physical regulation of estrogen, and current oral administration of tamoxifen has potential side effects on normal endocrine secretion. In the present work, we aim to develop novel approaches to increase the antitumor effect of tamoxifen on breast cancer cells and decrease the potential side effects in the human body during treatment. Methods: A temperature-sensitive phase-change hydrogel for tamoxifen (Tam-Gel) was generated. After establishing subcutaneous tumors formed by MCF-7, an ERα-positive breast cancer cell line, in nude mice, an intratumoral injection of Tam-Gel was performed to examine whether Tam-Gel facilitated the slow-release or antitumor effect of tamoxifen. A metastatic breast cancer model was established using the intrahepatic growth of MCF-7 cells in immunodeficient rats. Results: Tam-Gel can transform from liquid to hydrogel at room temperature. An intratumoral injection of Tam-Gel facilitated the slow-release or antitumor effect of tamoxifen. Once Tam-Gel, but not Tam-Sol, was administered by intratumoral injection, it significantly decreased the uptake of radionuclide probes (18F-fluoroestradiol or 18F-fluorodeoxyglucose) by cells in rats' livers and the intrahepatic growth of MCF-7 cells in rats' livers. Conclusion: A novel slow-release system was successfully prepared to facilitate the long-term release of tamoxifen in breast cancer tissues, and achieved an antitumor effect in the long term.

9.
J Cancer Res Clin Oncol ; 145(2): 411-427, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30483898

RESUMO

The pre-metastatic niche has been shown to play a critical role in tumor metastasis, and its formation is closely related to the tumor microenvironment. However, the underlying molecular mechanisms remain unclear. In the present study, we successfully established a mouse model of lung metastasis using luciferase-expressing MDA-MB-435s cells. In this model, recruitment of vascular endothelial growth factor receptor-1 (VEGFR1)+CD133+ hematopoietic progenitor cells (HPCs) was gradually increased in lung but gradually decreased after the formation of tumor colonies in lung. We also established a highly metastatic MDA-MB-435s (MDA-MB-435s-HM) cell line from the mouse model. Changes in protein profiles in different culture conditions were investigated by protein microarray analysis. The levels of CXC chemokine ligand 16, interleukin (IL)-2Rα, IL-2Rγ, matrix metalloproteinase (MMP)-1, MMP-9, platelet-derived growth factor receptor (PDGFR)-α, stromal cell-derived factor (SDF)-1α, transforming growth factor (TGF)-ß, platelet endothelial cell adhesion molecule (PECAM)-1 and vascular endothelial (VE)-cadherin were significantly greater (> fivefold) in the culture medium from MDA-MB-435s-HM cells than in that from MDA-MB-435s cells. Moreover, the levels of MMP-9, PDGFR-α, and PECAM-1 were significantly greater in the co-culture medium of MDA-MB-435s-HM cells and CD133+ HPCs than in that from MDA-MB-435s-HM cells. Differentially expressed proteins were validated by enzyme-linked immunosorbent assay, and expression of their transcripts was confirmed by quantitative real-time polymerase chain reaction. Moreover, inhibition of MMP-9, PDGFR-α, and PECAM-1 by their specific inhibitors or antibodies significantly decreased cell migration, delayed lung metastasis, and decreased recruitment of VEGFR1+CD133+ HPCs into lung. Intra-hepatic growth of HPCs enhanced the invasive growth of MDA-MB-435s-HM cells in the liver. Our data indicate that VEGFR1+CD133+ HPCs contribute to lung metastasis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Células-Tronco Hematopoéticas , Neoplasias Pulmonares/secundário , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Análise Serial de Proteínas , Bibliotecas de Moléculas Pequenas/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Hazard Mater ; 150(3): 494-503, 2008 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-17561342

RESUMO

The adsorption of two basic dyes (Basic Green 5 (BG5) and Basic Violet 10 (BV10)) onto titanate nanotubes (TNT) that were prepared via a hydrothermal method with different synthesis temperatures was studied to examine the potential of TNT for the removal of basic dyes from aqueous solution. Effects of synthesis temperature on the microstructures of TNT were characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption-desorption isotherms. For synthesis temperature greater than 160 degrees C, the microstructure of titanate might transform from nanotube into nanorod accompanying with the sharp decrease in the titanate interlayer spacing, BET surface area, and pore volume. Effects of the pore structure variation on the basic dyes adsorption of TNT were discussed. Moreover, the adsorption mechanisms of basic dyes from aqueous solution onto TNT were examined with the aid of model analyses of the adsorption equilibrium and kinetic data of BG5 and BV10. The regeneration of TNT was also briefly discussed.


Assuntos
Corantes/química , Nanotubos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Temperatura Alta , Cinética , Microscopia Eletrônica de Transmissão , Nanotubos/ultraestrutura , Porosidade , Propriedades de Superfície , Titânio/química , Difração de Raios X
11.
Onco Targets Ther ; 11: 7733-7743, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464522

RESUMO

BACKGROUND: Urokinase plasminogen activator (uPA) promotes the in vivo invasive growth of HCC cells by cleaving and activating matrix metalloproteinases (MMPs) to induce the destruction of the extracellular matrix of triple-negative breast cancer (TNBC) cells. The identification of microRNAs that target uPA and decrease uPA expression would be useful for attenuating the in vivo invasive growth of TNBC cells. MATERIALS AND METHODS: MicroRNA-645 (miR-645) was identified using an online tool (miRDB) as potentially targeting uPA; miR-645 inhibition of uPA was confirmed by western blot experiments. The effects of miR-645 on the in vivo invasive growth of TNBC cells were examined using an intrahepatic tumor model in nude mice, and the miR-645 mechanism of action was explored with MMP cleaving experiments. RESULTS: Through virtual screening, we discovered that miR-645 potentially targeted the uPA 3' untranslated region. This targeting was confirmed by western blot experiments and miR-645 lentiviral particle (LV-645) transduction that inhibited uPA expression in MDA-MB-231 TNBC cells. The LV-645 inhibition of uPA led to the decreased invasive growth of TNBC cells in nude mice. The mechanism data indicated that the uPA inhibition resulted in a decreased cleaving of the pro-MMP-9 protein. CONCLUSION: Targeting uPA with miR-645 decreased the in vivo invasive growth of TNBC cells. These results suggest that miR-645 may represent a promising treatment strategy for TNBC.

12.
Curr Pharm Des ; 24(15): 1682-1688, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29766795

RESUMO

INTRODUCTION: Although a great many strategies have been proposed for tumor-targeted chemotherapy, current delivery methods of anticancer drugs present limited success with inevitable systemic toxicity. The aim of this study was to develop a new kind of theranostic carrier for targeted tumor therapy. METHODS: Prior to prepare CHC-PFP-DOX, carboxymethyl-hexanoyl chitosan (CHC) was synthesized by acylation of carboxymethyl chitosan. To develop CHC-PFP, perfluoropentane (PFP), an ultrasound gas precursor, was simultaneously encapsulated into the hydrophobic inner cores of pre-formulated CHC micelle in aqueous phase via using the oil in water (O/W) emulsion method. The size distribution and surface charges of these nanodroplets were measured and the morphology was observed by transmission electron microscopy (TEM). For ultrasound imaging application, in vitro model was established to evaluate the imaging of CHC-PFP-DOX under different concentration and mechanical index. After that, the anti-tumor effect of ultrasound combined with CHC-PFPDOX on ovarian cancer cells was investigated. RESULTS: The resulting CHC-PFP-DOX had a nano-sized particle structure, with hydrophobic anticancer DOX/PFP inner cores and a hydrophilic carboxymethyl chitosan polymer outer shell. The favorable nano-scaled size offers the potential to extravagate from veins and accumulate in tumor tissues via enhanced permeation and retention (EPR) effect. Additionally, CHC-PFP-DOX showed the ability to serve as ultrasound imaging agent at body temperature. Notably, it exhibited an ultrasound-triggered drug release profile through the external ultrasound irradiation. Further study demonstrated that ultrasound combined with CHC-PFP-DOX can improve the killing effect of chemotherapy for tumor. CONCLUSION: CHC-PFP-DOX holds great promise in simultaneous cancer-targeting ultrasound imaging and ultrasound- mediated delivery for cancer chemotherapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Quitosana/análogos & derivados , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Ultrassonografia , Antibióticos Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Micelas , Neoplasias Ovarianas/patologia , Tamanho da Partícula , Propriedades de Superfície
13.
Artigo em Chinês | WPRIM | ID: wpr-981322

RESUMO

This paper explored the chemical constituents of Boswellia carterii by column chromatography on silica gel, Sephadex LH-20, ODS column chromatography, and semi-preparative HPLC. The structures of the compounds were identified by physicochemical properties and spectroscopic data such as infrared radiation(IR), ultra violet(UV), mass spectrometry(MS), and nuclear magnetic resonance(NMR). Seven diterpenoids were isolated and purified from n-hexane of B. carterii. The isolates were identified as(1S,3E,7E,11R,12R)-11-hydroxy-1-isopropyl-4,8,12-trimethyl-15-oxabicyclo[10.2.1]pentadeca-3,7-dien-5-one(1),(1R,3S,4R,7E,11E)-4,8,12,15,15-pentamethyl-14-oxabicyclo[11.2.1]hexadeca-7,11-dien-4-ol(2), incensole(3),(-)-(R)-nephthenol(4), euphraticanoid F(5), dilospirane B(6), and dictyotin C(7). Among them, compounds 1 and 2 were new and their absolute configurations were determined by comparison of the calculated and experimental electronic circular dichroisms(ECDs). Compounds 6 and 7 were obtained from B. carterii for the first time.


Assuntos
Estrutura Molecular , Boswellia/química , Diterpenos/química , Espectrometria de Massas
14.
J Colloid Interface Sci ; 316(2): 562-9, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17765912

RESUMO

Titanate nanotubes (TNT) were prepared via a hydrothermal treatment of TiO(2) powders (P25) in a 10 M NaOH solution at 150 degrees C for 24 h and subsequently washed with HCl aqueous solution of different concentrations (0.1, 0.01, and 0.001 N). Samples with different contents of remnant sodium in nanotubes were characterized, as synthesized and after heat-treatment, by transmission electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption isotherms. The photocatalytic activity of TNT was evaluated by photocatalytic oxidation of basic dye (basic violet 10 (BV10)) in water solution. It was found that if the sodium was not completely exchanged with proton, the removal of sodium increased the specific surface area (and pore volume), while the thermal stability was reduced. When the sodium content of TNT was approximately 0 wt% (nearly complete proton exchange), the nanotubular structure of titanates might be destroyed. The effects of the alterations of microstructures induced by the exchange of sodium and heat-treatment on the photocatalytic activity of TNT were discussed with the variations of specific surface area, pore volume, and the amounts of anatase phase in TNT.


Assuntos
Nanotubos/química , Hidróxido de Sódio/química , Temperatura , Titânio/química , Catálise , Tamanho da Partícula , Fotoquímica , Propriedades de Superfície
15.
J Hazard Mater ; 148(3): 756-60, 2007 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-17689860

RESUMO

The potential of adsorptive removal of basic dyes with titanate nanotubes (TNTs) and acid dyes with surfactant (hexadecyltrimethylammonium (HDTMA) chloride)-modified TNTs were investigated. TNTs were prepared via a hydrothermal method and subsequently washed with HCl aqueous solutions of different concentrations. The prepared TNTs were then mediated by the HDTMA ions through the cation exchange process. Effects of acid washing and HDTMA-modified process on the revolution of microstructure and surface chemistry characteristics of TNTs were characterized with XRD, nitrogen adsorption-desorption isotherms, and FTIR. The adsorption capacities of two basic dyes (two acid dyes) on TNTs (their HDTMA-modified version) at initial dye concentration of 2000 mg/L were measured. It was experimentally concluded that if the amount of Na(+) in the TNTs was not very low, the TNTs and their HDTMA-modified version might be a good adsorbent for the removal of basic and acid dyes from aqueous solution through the cation and anion exchange mechanism, respectively. The adsorption capacity for basic and acid dyes could reach 380 and 400 mg/g, respectively.


Assuntos
Corantes/química , Nanotubos , Titânio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Estrutura Molecular , Espectrofotometria Atômica , Tensoativos/química
16.
J Hazard Mater ; 147(3): 997-1005, 2007 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-17337117

RESUMO

The adsorption of three basic dyes (Rhodamine B (RB), Crystal Violet (CV), and Methylene Green (MG)) and two acid dyes (Acid Red 1 (AR1) and Erioglaucine (EG)) onto MCM-41 was studied to examine the potential of MCM-41 for the removal of dyes from water solution. The revolution of pore structure and surface chemical characteristics of MCM-41 induced by dyes adsorption was characterized based on the analyses of XRD patterns, FTIR spectra, and nitrogen adsorption-desorption isotherms. The adsorption capacity of MCM-41 for the five dyes followed a decreasing order of RB>CV>MG>EG approximately AR1. It was experimentally concluded that if the dyes adsorption did not introduce a serious disorder on the pore structure of MCM-41 (such as RB adsorption), MCM-41 might be a good adsorbent for the removal of basic dyes from water solution. The fitness of both Langmuir and Freundlich adsorption model on describing the equilibrium isotherms of three basic dyes was examined. The suitability of both pseudo-second-order kinetic model and the intraparticle diffusion model for the description of the kinetic data was investigated, from which the adsorption mechanism was examined.


Assuntos
Corantes/isolamento & purificação , Resíduos Industriais , Dióxido de Silício/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Difração de Raios X
18.
Oncotarget ; 8(54): 93103-93116, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29190981

RESUMO

The radioresistance of hepatocellular carcinoma (HCC) cells is a critical obstacle for effectively applying radiotherapy (RT) in HCC treatment. NF-κB, an important transcription factor, can influence critical cell fate decisions by promoting cell survival or anti-apoptosis in response to cell-stress, e.g. chemotherapies or ionizing radiation (IR). A20, also named as tumor necrosis factor α induced protein 3 (TNFAIP3), is a dominant negative regulator of NF-κB pathway and its functions in HCC are largely unknown. The present work aimed to reveal the role of A20 plays in affecting the radiosensitivity of HCC cells. Higher expression of A20 was detected in hepatic non-tumor cell line or clinical specimens compared with HCC cell lines or clinical specimens. A20 decreased the expression of proteins mediating cellular stress/injury response or epithelial-mesenchymal transition (EMT) process. Overexpression of A20 via adenovirus enhanced the effect of 60Co-γ ionizing radiation (IR) on HCC cells' injury, e.g. G2/M arrest or DNA double strands break (DSB). Moreover, A20 also enhanced the in vitro or in vivo survival inhibiting of HCC cells induced by IR. These results reveal the roles of A20 in HCC radiosensitization and overexpression of A20 would be a novel strategy for HCC radiotherapy.

19.
Journal of Forensic Medicine ; (6): 254-257, 2022.
Artigo em Inglês | WPRIM | ID: wpr-984117

RESUMO

OBJECTIVES@#To study the distribution of total phosphine in phosphine poisoning victims and summarize the characteristics of phosphine poisoning cases.@*METHODS@#The phosphine and its metabolites in the biological samples of 29 victims in 16 phosphine poisoning cases were qualified and quantified by headspace gas chromatography-mass spectrometry.@*RESULTS@#Five victims among 29 were poisoned by ingestion of aluminium phosphide and 24 by inhalation of phosphine gas. Phosphine metabolites were detected in the biological samples of 23 victims, and the concentrations of total phosphine in blood ranged 0.5-34.0 μg/mL. The total concentration of phosphine in liver tissue was up to 71.0 μg/g. Phosphine was not detected in the blood of the other six survived victims, which may be related to the small amount of phosphine exposure and the delay in blood sampling.@*CONCLUSIONS@#The total concentration of phosphine in blood and tissues caused by aluminum phosphine ingestion is higher than that caused by phosphine gas inhalation. The death cases of phosphine inhalation are characterized by long exposure time, repeated exposures and age susceptibility.


Assuntos
Humanos , Compostos de Alumínio/análise , Cromatografia Gasosa-Espectrometria de Massas , Fígado/química , Fosfinas/análise , Intoxicação/diagnóstico
20.
Artigo em Chinês | WPRIM | ID: wpr-1015680

RESUMO

Mitochondria are dynamic organelles that continuously divide and fuse. In recent years, in addition to the studies related to mitochondrial metabolism, the unique dynamics of mitochondria have gradually attracted researchers' attention. A growing body of research has revealed that mitochondrial dynamics are related to the biological behavior of tumor cells. Mitochondrial fission proteins (mitochondrial fission protein 1, FIS1) mediate the assembly of mitochondrial fission complexes and participate in the execution of mitochondrial fission. They are important proteins in the process of mitochondrial fusion and fission. However, few studies have revealed the expression and role of FIS1 in human cervical cancer. In this study, the expression level of FIS1 in human cervical cancer tissues and paracancer tissues were compared. The results showed that the level of FIS1 mRNA in human cervical cancer tissues was significantly lower than that in paracancer tissues (P<0. 01). Further KEGG pathway and GO Term-BP pathway analysis showed that the differential genes are mainly related to mitochondrial biological functions. Subsequently, HeLa cells with overexpressed FIS1 were investigated for their proliferation, migration, mitochondrial fission and ROS levels. The experimental results showed that FIS1 overexpression decreased HeLa cell proliferation and migration ability, enhanced mitochondrial fission and higher ROS levels. In conclusion, the expression of FIS1 in human cervical cancer cells was attenuated, while overexpression of FIS1 resulted in a series of abnormal biological functions in human cervical cancer cells. Further studies can be carried out to investigate the role of FIS1 in the treatment of human cervical cancer.

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