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1.
Nanotechnology ; 35(1)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37783207

RESUMO

In order to reduce the etching effect of the catalysts to carbon fibers caused by high temperature during the chemical vapor deposition (CVD) process, four multi-element catalysts, Fe-Co, Fe-Ni, Co-Ni and Fe-Co-Ni, were used to realize the low temperature growth of carbon nanotubes (CNTs) on carbon fibers at 350 °C-400 °C. The results show that the growth state of CNTs has a great relationship with the type of catalysts. The catalytic efficiency of Fe-Co catalysts is low, but the graphitization degree of CNTs is relatively high. The Fe-Co-Ni catalysts has high catalytic efficiency but low graphitization degree of CNTs. The tensile strength of carbon fiber/CNTs reinforcements prepared by Fe-Ni catalysts at 400 °C is the highest, reaching 3.99 GPa, which is 11.14% higher than that of desized fiber. The melt drop phenomenon of the catalysts was found by TEM, indicating the formation of the liquid phase catalysts during the growth of CNTs. This phenomenon can change the diffusion mode of carbon atoms in the catalyst and significantly reduce the growth activation energy of CNTs, so that CNTs can grow at lower temperatures. Based on the detailed analysis of the CVD process, a low temperature growth model of CNTs on carbon fibers was proposed.

2.
Small ; 19(50): e2304918, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37626450

RESUMO

Developing composite materials with the synergistic effects of heterogeneous structures and multiple components is considered as a promising strategy to achieve high-performance electromagnetic wave (EMW) absorbers. To further satisfy the demand of broadband and strong microwave absorption, a novel NiS/carbon nanofibers (CNFs)/porous carbon composite is successfully synthesized by hydrothermal and chemical vapor deposition using lotus leaves as a biomass carbon source. A few carbon nanotubes (CNTs) and uniformly dispersed Ni nanocrystals have also been found in the hybrid. Benefiting from the porous structure derived from lotus leaves, the combination of dielectric NiS, conductive carbon nanomaterials, and magnetic Ni nanoparticles, together with the three-dimensional conductive network of CNFs and CNTs, the remarkable EMW absorption properties with a minimum reflection loss up to -67.65 dB have been achieved at merely 2.32 mm. Besides, the widest effective absorption band can reach 5.9 GHz with a thin thickness of 2.07 mm, covering almost the entire Ku band. In addition, under the incident angle of 31°, the radar cross-section reduction value of LNSF-600 can reach 42.88 dBm2. Therefore, this work provides an efficient and facile method for manufacturing outstanding biomass-derived EMW absorbers.

3.
J Colloid Interface Sci ; 637: 123-133, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36689798

RESUMO

Modulating the structure and morphology is essential in fabricating high-performance electromagnetic absorbing materials. Herein, we obtained porous Fe3O4/carbon hollow microspheres and porous Fe4N/carbon hollow microspheres derived from Fe-glycerol hollow microspheres. Through structure and morphology analysis, we proved the existence of porous and hollow features. By comparison, it can be found that the porous Fe4N/carbon hollow microspheres have electromagnetic wave absorption performance superior to that of porous Fe3O4/carbon hollow microspheres. The reflection loss value of porous Fe4N/carbon hollow microspheres reaches -42.2 dB at a matching thickness of merely 1.4 mm, and its effective absorbing bandwidth approaches 4.5 GHz, whereas the reflection loss of porous Fe3O4/carbon hollow microspheres in the 2-18 GHz range is over -10 dB. Reasons for the better electromagnetic wave absorption performance are revealed to be that the magnetic Fe4N has higher complex permittivity and complex permeability, and the porous hollow microspherical structure increases the multiple scattering and reflection of electromagnetic waves. Meanwhile, the impedance matching and attenuation constant are optimized together through the synergy of dielectric and magnetic loss. This research can provide instructive findings for thin-thickness electromagnetic wave absorbing materials based on Fe4N with an appropriate microstructure.

4.
Materials (Basel) ; 15(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36431362

RESUMO

Carbon fiber composites as pantograph slide materials are in the development stage, in which copper is the conductive phase, and the addition form and size need to be designed. Herein, the effects of the copper morphology, the size of the copper mesh on the performance, and the influence of the contact mode between the sliding plate and bracket on the temperature rise were compared and analyzed. The resistivity is 11.2 µΩ·m with the addition of 20 wt% copper mesh, a relative reduction of 91.77%. Importantly, the impact strength is increased by 14.19%, and the wear is reduced by 13.21%; hence, the copper mesh laid in layers is the ideal structure. Further study of the distribution and quality of the copper mesh shows that the resistivity is related only to the quality of the copper mesh; in addition, the number of layers of the copper mesh cannot exceed 16, and it is determined that the best type of copper mesh is 5#. Notably, the performance can be improved by appropriately reducing the thickness of the copper mesh and increasing the aperture while the sliding plate and the bracket are connected by copper mesh with conductive adhesive, which has the slowest heating rate of 2.27 °C/min and the smallest resistance. Therefore, the influence of copper content and distribution on the electrical conductivity are systematically investigated, and the mechanical properties and electrical conductivity are optimized through the design of the laminate structure of the compound material.

5.
RSC Adv ; 12(26): 16751-16762, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35754910

RESUMO

Zeolite supported amorphous metal oxide nanolayers with high specific surface area, abundant adsorption sites, and excellent reusability hold a bright prospect in the efficient removal of contaminants, yet it is proven to be still challenging to precisely regulate and control their synthesis. Herein, we reported a facile synthetic strategy for rational design and achieving the uniform and firm in situ growth of an amorphous ZrO2 layer decorated on the surface of zeolite (ZEO@AZ) for enhanced phosphate adsorption. The Langmuir isotherm model and pseudo-second order kinetic equation well described the adsorption process towards phosphate solution, and the synthetized ZEO@AZ exhibited an excellent maximum adsorption amount of 24.98 mgP g-1. Furthermore, the adsorption of phosphates on ZEO@AZ was confirmed to be chemisorption, endothermic and spontaneous. This approach for fabricating amorphous metal oxide nanolayers on a robust matrix may provide a new route for constructing composites with superb phosphate adsorption performance.

6.
Langmuir ; 38(7): 2392-2400, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35148119

RESUMO

Two kinds of carbon nanoproducts with different microstructures, namely, carbon nanotubes (CNTs) and carbon nanofibers (CNFs), were grown on the surface of carbon fibers (CFs) by chemical vapor deposition (CVD) at low temperatures to improve the interface bonding between fibers and resins. The short-beam method and the micro-debonding method were used to test the interlaminar shear strength (ILSS) and interfacial shear strength (IFSS) of the composites. The results showed that the contribution of CNTs to the improvement of interfacial properties was better than that of CNFs. Specifically, the ILSS and IFSS of the CF-CNFs/epoxy composites increased by 18.59 and 24.39%, respectively, while the ILSS and IFSS of the CF-CNTs/epoxy composites increased by 26.97 and 47.79%, respectively. Compared with CNFs, the high degree of graphitization of CNTs and the π-interactions with the resin can better induce the formation of an interphase between the fiber and the resin, which suppressed the initiation of cracks and extended the propagation path of the cracks in the composites.

7.
ACS Appl Mater Interfaces ; 13(43): 50936-50947, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34668370

RESUMO

To date, elemental sulfur has been considered as a prospective cathode material for exploring high-energy power systems with low cost and sustainability. However, its practical commercialization has been impeded by inherent drawbacks of notorious capacity decay, unsatisfied insulating nature, and sluggish conversion chemistry. To address these issues, for the first time, freestanding nanofibrous networks with hierarchical nanostructures are facilely constructed by inlaying electrocatalytic bimetallic chalcogenides (FexMn1-xS nanoparticles) into conductive graphene nanosheet (GN)-doped sulfurized polyacrylonitrile (SPAN) fiber matrices. Covalent-bonded SPAN featuring an insoluble mechanism serves as a reliable cathode substrate with enhanced electrostability and high sulfur utilization, while high-surface-area GN dopants promote conductivity improvement and rapid electron transfer. Meanwhile, the results prove that sulfiphilic FexMn1-xS nanoparticles with abundant electrochemically active sites facilitate construction of uniform deposition interfaces and efficient electrocatalysis conversion toward lithium polysufides. This feasible catalytic-insoluble cathode strategy drives the Li-S battery, which exhibits excellent electrochemical performances with a remarkable reversible discharge capacity of 967 mA h g-1 and a capacity retention of 623 mA h g-1 after 500 cycles. Moreover, the corresponding lithiation/delithiation mechanisms are systematically investigated through complementary morphological and spectral analyses, providing valuable insights into advanced metal-sulfur batteries.

8.
Nanotechnology ; 32(28)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33823501

RESUMO

Carbon nanotubes (CNTs) were continuously grown on the surface of the moving carbon fiber by chemical vapor deposition method using a custom-designed production line to prepare composite reinforcements on a large-scale. The systematic study of different parameters affecting the CNT growth revealed simple growth kinetics, which helps to control the surface morphology and structural quality of CNTs. Since hydrogen maintains the activity of the catalyst, it promotes the growth of CNTs in a continuous process. The increase of acetylene partial pressure promotes the accumulation of amorphous or graphite carbon on the catalyst surface, resulting in the decrease of CNT growth rate when acetylene concentration reaches 40%. The growth temperature significantly affects the CNT diameter and structural quality. As the temperature increases, the crystallinity of the tube wall increases obviously, and the CNT diameter increases due to the aggregate growth of the catalyst particles. According to the Arrhenius formula, the apparent activation energy is observed to be 0.67 eV, which proves that both bulk diffusion and surface diffusion exist when activated carbon passes through the catalyst to form CNTs.

9.
Small ; 16(42): e2003386, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32964701

RESUMO

The boosting demand for high-capacity energy storage systems requires innovative battery technologies with low-cost and sustainability. The advancement of potassium-sulfur (K-S) batteries have been triggered recently due to abundant resource and cost effectiveness. However, the functional performance of K-S batteries is fundamentally restricted by the vague understanding of K-S electrochemistry and the imperfect cell components or architectures, facing the issues of low cathode conductivity, intermediate shuttle loss, poor anode stability, electrode volume fluctuation, etc. Inspired by considerable research efforts on rechargeable metal-sulfur batteries, the holistic K-S system can be stabilized and promoted through various strategies on rational physical regulation and chemical engineering. In this review, first an attempt is made to address the electrochemical kinetic concept of K-S system on the basis of the emerging studies. Then, the classification of performance-improving strategies is thoroughly discussed in terms of specific battery component and prospective outlooks in materials optimization, structure innovations, as well as relevant electrochemistry are provided. Finally, the critical perspectives and challenges are discussed to demonstrate the forward-looking developmental directions of K-S batteries. This review not only endeavors to provide a deep understanding of the electrochemistry mechanism and rational designs for high-energy K-S batteries, but also encourages more efforts in their large-scale practical realization.

10.
Ann Transl Med ; 8(8): 541, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32411764

RESUMO

BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR) is considered as a prognostic predictor of hepatocellular carcinoma (HCC). However, its prognostic ability is still controversial. This study aimed to evaluate the prognostic value of NLR changes in HCC patients undergoing transarterial chemoembolization (TACE). METHODS: The patients who were newly diagnosed with HCC and treated with TACE in our center from July 2010 to December 2014 were enrolled in the study. The factors, including NLR, were recorded at baseline and three days and one month after TACE. RESULTS: A total of 380 consecutive patients were studied retrospectively. The median NLR values at baseline, 3 days and 1 month after TACE (2.4, 6.3 and 2.4 respectively), were used as the cut-off value for patient stratification. Compared with the patients in low NLR group, those with high NLR had a larger tumor size. For baseline measurement, the low NLR group showed improved overall survival (OS) compared with the high group (median OS, 27.1 vs. 15.6 months, P=0.004). There was no survival difference between the low and high NLR groups when measured at 3 days and at 1 month after TACE (P>0.05). Multivariate analysis showed that baseline NLR >2.4 was an independent prognostic predictor of poor OS. There was significant survival difference between the normal NLR group and the high or increased NLR group, with a median OS of 29.1 and 19.1 months, respectively (P=0.023). CONCLUSIONS: The dynamic changes of baseline NLR are significantly associated with OS in HCC patients treated with TACE, and as a result patient selection and prognostic prediction may be refined.

11.
Ann Transl Med ; 8(8): 542, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32411765

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a common cancer worldwide and prognosis for patients with the disease remains poor. Most patients are diagnosed at an advanced stage and are only eligible for palliative therapy. As a novel vascular endothelial growth factor receptor-2 tyrosine kinase inhibitor (VEGFR2-TKI), apatinib has a certain antitumor effect for a variety of solid tumors. In clinical practice, clinicians have attempted to treat intermediate- to advanced-stage HCC patients with a combination of transcatheter arterial chemoembolization (TACE) and apatinib. However, a consensus on the therapeutic effects of this treatment is yet to be reached. This meta-analysis was conducted to compare the therapeutic efficacy and clinical safety of the combination therapy of TACE plus apatinib with that of TACE alone in patients with intermediate- to advanced-stage HCC. METHODS: Relevant studies were identified by searching PubMed, Embase, Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Biomedical Literature Database (CBM), Chinese Science and Technology Periodical Database (VIP) and the reference lists of retrieved articles up to July 31, 2019. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated to express the therapeutic effects of TACE plus apatinib versus TACE on survival, objective response rate, disease control rate, progressive disease rate and adverse events using a mixed-effect model. Subgroup analyses of study type, dosage of apatinib, TACE regimen, study sample size between treatment groups and control groups were performed. Publication bias was assessed using fail-safe N, Begg-Mazumdar test and Egger's test. RESULTS: From 23 eligible studies, a total of 1,342 patients were included in this review and meta-analysis. Among these studies, 18 were randomized clinical trials and 5 were case-control studies. Compared with those being treated with TACE alone, patients receiving TACE plus apatinib showed significantly better half-year survival (OR, 2.741, 95% CI, 1.745-4.306) and 1-year survival (OR, 2.284, 95% CI, 1.442-3.620). The superiority of TACE and apatinib over TACE monotherapy was evident in the disease control rate (OR, 2.919, 95% CI, 2.184-3.903), objective response rate (OR, 2.683, 95% CI, 2.099-3.429) and progressive disease rate (OR, 0.341, 95% CI, 0.255-0.456), respectively. CONCLUSIONS: The combination treatment of apatinib and TACE provides better survival benefits for intermediate- to advanced-stage HCC patients when compared to TACE monotherapy and should be recommended for suitable patients with unresectable HCC. However, further investigation into future prospective clinical studies is warranted.

12.
Microsc Res Tech ; 82(12): 2026-2034, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31487086

RESUMO

The microfibrils served as the structural elements in polyacrylonitrile (PAN) fiber, which played an important role in the quality of the PAN precursor fibers. Their morphologies were examined by the scanning electron microscopy (SEM), atomic force microscopy (AFM) and high-resolution transmission electron microscope (HRTEM). The microfibrils existed in all of PAN fibers and arranged evenly in the cross-sections. Furthermore, the pores existed between the microfibrils. The unoriented microfibrillar network was already formed in nascent fiber during coagulated process. Although the microfibrillar network was elongated and the microfibrils oriented along the fiber longitudinal direction during the spinning process, the interconnected microfibrillar network was still existed in the fiber transverse section. Furthermore, the transverse connection of the microfibrils was reinforced and the small microfibrils were tended to aggregate into the large fibrils. For mechanical performance of PAN fibers, their tensile strength increased to 708 MPa and the elongation at break decreased to 15.5%. PAN fibers exhibited ductile rupture during the mechanical test and the microfibrils served as reinforcing elements.

13.
Oncol Lett ; 17(2): 1903-1913, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30675254

RESUMO

microRNAs (miRNAs) have been determined to be associated with cancer progression and metastasis. Mir-139 is located on 11q13.4 and exhibits anti-oncogenic and anti-metastatic activity in human cancers. It is downregulated in various malignant tumor types. In the present study, the potential functions and targets of miR-139 in hepatocellular carcinoma (HCC) were explored. Using a combinational analysis of four miRNA target prediction tools and biological experiments, it was determined that Topoisomerase I (TOP1) is a direct target of miR-139 in HCC. Several traditional topoisomerase inhibitors have demonstrated anticancer activity, but their side effects outnumbered their anticancer potential. The present study determined that overexpression of miR-139 significantly inhibits HCC cell proliferation (P<0.05) and migration (P<0.05), which is largely due to TOP1 downregulation. The present study indicated that miR-139 exerts a tumor-suppressive effect during hepatocarcinogenesis via the suppression of expression of TOP1; therefore, miR-139 is a promising target for the treatment of HCC.

14.
Nanotechnology ; 29(39): 395602, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29972379

RESUMO

An effective approach has been developed for the catalytic decomposition of acetylene (C2H2) by chemical vapor deposition (CVD), to achieve homogeneous growth of carbon nanotubes (CNTs) on the surfaces of carbon fibers. The morphology of CNTs grown on carbon fiber surfaces was observed by a scanning electron microscope and high-resolution transmission electron microscope, which revealed the uniform coverage of CNTs on the carbon fiber surfaces. The single fiber tensile test demonstrated that the tensile strength of carbon fibers could be increased by more than 12% with the catalytic growth of CNTs on their surface. The reparation of the damage caused during the formation of catalyst nanoparticles, and the cross-link of neighboring graphite crystallites induced by CNTs all occurred during the CVD process, which were considered to be the main reasons for improvement. The growth mechanism model of CNTs formation was established based on the thermodynamics principle and the interface microstructure of CNT-grown carbon fiber, illuminating the detailed mechanism for the growth of CNTs and the change of the shape of catalyst particles.

15.
Artigo em Inglês | MEDLINE | ID: mdl-28335450

RESUMO

The present work is the first systematic and large scale study on radioactive materials and heavy metals in surface soil around the Bayanwula prospective uranium mining area in China. In this work, both natural and anthropogenic radionuclides and heavy metals in 48 surface soil samples were analyzed using High Purity Germanium (HPGe) γ spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS). The obtained mean activity concentrations of 238U, 226Ra, 232Th, 40K, and 137Cs were 25.81 ± 9.58, 24.85 ± 2.77, 29.40 ± 3.14, 923.0 ± 47.2, and 5.64 ± 4.56 Bq/kg, respectively. The estimated average absorbed dose rate and annual effective dose rate were 76.7 ± 3.1 nGy/h and 83.1 ± 3.8 µSv, respectively. The radium equivalent activity, external hazard index, and internal hazard index were also calculated, and their mean values were within the acceptable limits. The estimated lifetime cancer risk was 3.2 × 10-4/Sv. The heavy metal contents of Cr, Ni, Cu, Zn, As, Cd, and Pb from the surface soil samples were measured and their health risks were then assessed. The concentrations of all heavy metals were much lower than the average backgrounds in China except for lead which was about three times higher than that of China's mean. The non-cancer and cancer risks from the heavy metals were estimated, which are all within the acceptable ranges. In addition, the correlations between the radionuclides and the heavy metals in surface soil samples were determined by the Pearson linear coefficient. Strong positive correlations between radionuclides and the heavy metals at the 0.01 significance level were found. In conclusion, the contents of radionuclides and heavy metals in surface soil around the Bayanwula prospective uranium mining area are at a normal level.


Assuntos
Metais Pesados/análise , Mineração , Poluentes do Solo/análise , Solo/química , China , Estudos Prospectivos , Radioatividade , Espectrometria gama , Urânio/análise
16.
Langmuir ; 32(33): 8339-49, 2016 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-27472250

RESUMO

In an attempt to improve the mechanical properties of carbon fiber composites, propagation of poly(amidoamine) (PAMAM) dendrimers by in situ polymerization on a carbon fiber surface was performed. During polymerization processes, PAMAM was grafted on carbon fiber by repeated Michael addition and amidation reactions. The changes in surface microstructure and the chemical composition of carbon fibers before and after modification were investigated by atomic force microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. All the results indicated that PAMAM was successfully grown on the carbon fiber surface. Such propagation could significantly increase the surface roughness and introduce sufficient polar groups onto the carbon fiber surface, enhancing the surface wettability of carbon fiber. The fractured surface of carbon fiber-reinforced composites showed a great enhancement of interfacial adhesion. Compared with those of desized fiber composites, the interlaminar shear strength and interfacial shear strength of PAMAM/fiber-reinforced composites showed increases of 55.49 and 110.94%, respectively.

17.
Ecotoxicol Environ Saf ; 130: 185-92, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27107776

RESUMO

Natural and artificial radionuclides and heavy metals in the surface soil of the uranium mining area of Tongliao, China, were measured using gamma spectrometry, flame atomic absorption spectrophotometry, graphite furnace atomic absorption spectrophotometry and microwave dissolution atomic fluorescence spectrometry respectively. The estimated average activity concentrations of (238)U, (232)Th, (226)Ra, (40)K and (137)Cs are 27.53±16.01, 15.89±5.20, 12.64±4.27, 746.84±38.24 and 4.23±4.76Bq/kg respectively. The estimated average absorbed dose rate in the air and annual effective dose rate are 46.58±5.26nGy/h and 57.13±6.45µSv, respectively. The radium equivalent activity, external and internal hazard indices were also calculated and their mean values are within the acceptable limits. The heavy metal concentrations of Pb, Cd, Cu, Zn, Hg and As from the surface soil were measured and their health risks were then determined. Although the content of Cd is much higher than the average background in China, its non-cancer and cancer risk indices are all within the acceptable ranges. These calculated hazard indices to estimate the potential radiological health risk in soil and the dose rate are well below their permissible limit. In addition the correlations between the radioactivity concentrations of the radionuclides and the heavy metals in soil were determined by the Pearson linear coefficient.


Assuntos
Exposição Ambiental/análise , Mineração , Doses de Radiação , Radioisótopos/análise , Solo/química , Urânio/análise , Poluentes Radioativos do Ar/análise , Arsênio/análise , Cádmio/análise , Radioisótopos de Césio/análise , China , Cobre/análise , Humanos , Chumbo/análise , Mercúrio/análise , Potássio/análise , Radioatividade , Rádio (Elemento)/análise , Medição de Risco , Poluentes Radioativos do Solo/análise , Espectrometria gama , Espectrofotometria Atômica , Tório/análise , Zinco/análise
18.
Oncol Res ; 23(1-2): 43-51, 2016 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-26802650

RESUMO

Medullary thyroid carcinoma (MTC) is an uncommon and highly aggressive tumor of the neuroendocrine system, which derives from the neuroendocrine C cells of the thyroid gland. Except for surgical resection, there are not very many effective systemic treatment options for MTC. N-Myc downstream-regulated gene 2 (NDRG2) had a significantly lower expression in MTC compared with normal thyroid tissue. However, the function of NDRG2 in MTC oncogenesis is largely unknown. In this study, we found that overexpression of NDRG2 inhibited the proliferation of TT cells (human medullary thyroid carcinoma cells) in vitro and suppressed the development of MTC in a nude mouse xenograft model. Further analysis revealed that NDRG2 arrested the cell cycle G0/G1 phase progression and induced TT cell apoptosis. Moreover, NDRG2 overexpression may mediate the antiproliferative effect by reducing cyclin D1 and cyclin E protein levels. We also found aberrant NDRG2-mitigated TT cell migration and invasion in vitro. Sodium/iodide symporter (NIS) mediates active I(-) transport into the thyroid follicular cells, and radionuclide treatment is a promising therapy for MTC. Our current data revealed that NDRG2 overexpression enhanced NIS level in TT cells and increased their iodine uptake in vitro. Furthermore, (99m)TcO4(-) radionuclide imaging of the xenograft tumors indicated that NDRG2 could promote NIS-mediated radionuclide transport. In conclusion, the present study suggested that NDRG2 is a critical molecule in the regulation of MTC biological behavior and a potential promoter in radioactive iodine therapy.


Assuntos
Radioisótopos do Iodo/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Neoplasias da Glândula Tireoide/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose , Carcinogênese/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Expressão Gênica , Humanos , Radioisótopos do Iodo/metabolismo , Camundongos Nus , Transplante de Neoplasias , Cintilografia , Compostos Radiofarmacêuticos/metabolismo , Pertecnetato Tc 99m de Sódio/farmacocinética , Simportadores/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Proteínas Supressoras de Tumor/genética
19.
Pathol Oncol Res ; 19(3): 397-403, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23242568

RESUMO

As important regulators of chromatin, histone deacetylases (HDACs) are involved in silencing tumor suppressor genes. HDAC2, a member of HDACs, has been demonstrated to be implicated in the development and progression of various human malignancies; however, its expression and role in human primary gallbladder carcinoma (PGC) are not fully understood. Therefore, we conducted this study to address this problem. The subjects were 136 patients underwent resection for PGC. Immunostainings for HDAC2 were performed on these archival tissues. The correlation of HDAC2 expression with clinicopathological characteristics including survival was analyzed. HDAC2 was positively expressed in the nucleus of tumor cells in 86.0 % (117/136) of PGC but not in the normal epithelium of the gallbladder. Additionally, there was a significant difference in the incidence of positive nodal metastasis between high and low HDAC2 expression groups (P = 0.001). The incidences of advanced clinical stage (P = 0.005) and pathologic T stage (P < 0.001), and higher histologic grade (P < 0.001) were respectively higher in the high HDAC2 expression group than in the low group. Moreover, univariate and multivariate analyses revealed the high HDAC2 expression to be an independent prognostic factor for both overall and disease-free survival of patients with PGC. High HDAC2 expression was correlated with a high incidence of lymph node metastasis and aggressive tumor progression of PGC. It also was an independent prognostic factor for poorer overall and disease-free survival in patients. Therefore, detection of HDAC2 expression may help us screen patients at increased risk of malignant behavior for PGC.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias da Vesícula Biliar/enzimologia , Neoplasias da Vesícula Biliar/patologia , Histona Desacetilase 2/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Especificidade de Órgãos , Prognóstico
20.
Diagn Pathol ; 7: 41, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22510499

RESUMO

AIM: SOX4, as a member of the SRY-related HMG-box (SOX) transcription factor family, has been demonstrated to be involved in tumorigenesis of many human malignancies; however, its role in primary gallbladder carcinoma (PGC) is still largely unknown. The aim of this study was to investigate SOX4 expression in PGC and its prognostic significance. METHODS: From 1997 to 2006, 136 patients underwent resection for PGC. The median follow-up was 12.8 months. Immunostainings for SOX4 were performed on these archival tissues. The correlation of SOX4 expression with clinicopathological features including survival was analyzed. RESULTS: SOX4 was expressed in 75.0% (102/136) of PGC but not in the normal epithelium of the gallbladder. In addition, the over-expression of SOX4 was significantly associated with low histologic grade (P = 0.02), low pathologic T stage (P = 0.02), and early clinical stage (P = 0.03). The levels of SOX4 immunostainings in PGC tissues with positive nodal metastasis were also significantly lower than those without (P = 0.01). Moreover, Kaplan-Meier curves showed that SOX4 over-expression was significantly related to better overall (P = 0.008) and disease-free survival (P = 0.01). Furthermore, multivariate analyses showed that SOX4 expression was an independent risk factor for both overall (P = 0.03, hazard ratio, 3.682) and disease-free survival (P = 0.04, hazard ratio, 2.215). CONCLUSION: Our data indicate for the first time that the over-expression of SOX4 in PGC was significantly correlated with favorable clinicopathologic features and was an independent prognostic factor for better overall and disease-free survival in patients. Therefore, SOX4 might be an auxiliary parameter for predicting malignant behavior for PGC. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1534825818694957.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Vesícula Biliar/metabolismo , Fatores de Transcrição SOXC/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Transcrição SOXC/análise
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