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1.
Nanotechnology ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33540385

RESUMO

The design of high-efficient and stable electrocatalysts for oxygen reduction reaction (ORR) is still a great challenge. Herein, we prepared Co,N-codoped carbon nanocomposites (Co@NC-ZM) with entangled carbon nanotubes. The large BET surface area (604.7 m2 g-1), rich mesoporous feature, Co,N doping and synergetic effect between various species of Co@NC-ZM can expose more active sites and facilitate the conductivity and mass transport. Benefiting from above unique superiorities, Co@NC-ZM performs excellent ORR performance with the more positive onset potential (0.96 V) and half-wave potential (0.83 V) than those of the commercial Pt/C (0.96 and 0.81 V, correspondingly). This work provides a new strategy for further exploring efficient non-precious metal-based catalysts for ORR.

2.
Sci Rep ; 11(1): 4145, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603047

RESUMO

The pandemic of Coronavirus Disease 2019 (COVID-19) is causing enormous loss of life globally. Prompt case identification is critical. The reference method is the real-time reverse transcription PCR (RT-PCR) assay, whose limitations may curb its prompt large-scale application. COVID-19 manifests with chest computed tomography (CT) abnormalities, some even before the onset of symptoms. We tested the hypothesis that the application of deep learning (DL) to 3D CT images could help identify COVID-19 infections. Using data from 920 COVID-19 and 1,073 non-COVID-19 pneumonia patients, we developed a modified DenseNet-264 model, COVIDNet, to classify CT images to either class. When tested on an independent set of 233 COVID-19 and 289 non-COVID-19 pneumonia patients, COVIDNet achieved an accuracy rate of 94.3% and an area under the curve of 0.98. As of March 23, 2020, the COVIDNet system had been used 11,966 times with a sensitivity of 91.12% and a specificity of 88.50% in six hospitals with PCR confirmation. Application of DL to CT images may improve both efficiency and capacity of case detection and long-term surveillance.

3.
Environ Sci Technol ; 55(3): 2037-2047, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33435681

RESUMO

Roxarsone (ROX) has been widely used as an organoarsenic additive in animal feeding operations and poses a risk to the environment. Here, we first report the efficient degradation of ROX by UV/chlorine, where the kinetics, removal of total arsenic (As), and cytotoxicity were investigated. The kinetics study presented that reactive chlorine species (RCS) and HO• were the dominant species to react with ROX. Furthermore, the degradation rate of ROX can reach the maximum value at pH 7.5 due to the formation of more RCS. The degradation of ROX was affected by the amount of chlorine, pH, and water matrix. Through product analysis and Gauss theoretical calculation, two possible ROX degradation pathways were proposed. The free radicals attacked the As-C bond of ROX and resulted in releasing arsenate (As(V)). It was the reason that for an enhancement of the removal of total As by ferrous appeared after UV/chlorine, and over 98% of the total As was removed. In addition, cytotoxicity studies indicated that the cytotoxicity significantly enhanced during the degradation of ROX by UV/chlorine. However, by combination of UV/chlorine and adsorption, cytotoxicity can be greatly eliminated, probably due to the removal of As(V) and chlorinated products. These results further demonstrated that UV/chlorine treatment could be an effective method for the control of the potential environmental risks posed by organoarsenic.

4.
Sci Total Environ ; 760: 144304, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341627

RESUMO

Benzothiazole (BZA) and benzotriazole (BTZ) as emerging contaminants were found persistent in aquatic environments and toxic to aquatic organisms. The degradation of BZA and BTZ by UV/chlorine was systematically investigated in this study, and the results showed that BZA and BTZ can be remarkably removed by UV/chlorine compared with UV alone and dark chlorination. The radical quenching tests showed that degradation of BZA and BTZ by UV/chlorine involved the participation of reactive chlorine species (RCS), hydroxyl radical (HO·), and UV photolysis. HO· dominated BZA degradation at neutral and alkalinity, while RCS dominated BTZ degradation. The second-rate order constants for ClO· and BZA and BTZ were 2.22 × 108 M-1 s-1, and 2.40 × 108 M-1 s-1, respectively. Besides, the second-order rate constants for HO· and BZA and BTZ were also determined at pH 5.0, 7.0, and 9.0, respectively. The degradation efficiency of BZA by UV/chlorine was substantially promoted at acidic conditions, while the degradation efficiency of BTZ was promoted at both acidic and specific alkaline range mainly due to the reactivity of radical species and deprotonated form. The influence of Cl- was negligible, but the suppression effect of humic acid was slight during the BZA and BZT degradation by UV/chlorine. The transformation products were detected and the possible pathways were proposed. Seven disinfection by-products (DBPs) were identified both in BZA and BTZ degradation and trichloromethane was the main DBP. The toxicity assessment performed by luminescent bacteria and ECOSAR analysis indicated that the detoxification of BZA could be achieved by UV/chlorine, whereas the toxicity of BTZ was increased mainly due to the formation of intermediates. The findings from this study demonstrated UV/chlorine is likewise efficient for BZA and BTZ removal but the toxicity should be considered in the BTZ degradation.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Benzotiazóis/toxicidade , Cloro/toxicidade , Desinfecção , Halogenação , Cinética , Oxirredução , Triazóis , Raios Ultravioleta , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
7.
Drug Deliv ; 26(1): 732-743, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31340678

RESUMO

Multifunctional core-shell nanocarriers based on zinc oxide (ZnO)-gated magnetic mesoporous silica nanoparticles (MMSN) were prepared for cancer treatment through magnetic targeting and pH-triggered controlled drug release. Under an external magnetic field, the MMSN could actively deliver chemotherapeutic agent, daunomycin (DNM), to the targeted sites. At neutral aqueous, the functionalized MMSN could stably accommodate the DNM molecules since the mesopores were capped by the ZnO gatekeepers. In contrast, at the acid intercellular environment, the gatekeepers would be removed to control the release of drugs due to the dissolution of ZnO. Meanwhile, ZnO quantum dots not only rapidly dissolve in an acidic condition of cancer cells but also enhance the anti-cancer effect of Zn2+. An in vitro controlled release proliferation indicated that the acid sensitive ZnO gatekeepers showed well response by the 'on-off' switch of the pores. Cellular experiments against cervical cancer cell (HeLa cells) further showed that functionalized MMSN significantly suppressed cancer cells growth through synergistic effects between the chemotherapy and Zn2+ ions with monitoring the treatment process. These results suggested that the ZnO-gated MMSN platform is a promising approach to serve as a pH-sensitive system for chemotherapies delivery and Zn2+ controlled release for further application in the treatment of various cancers by synergistic effects.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Daunorrubicina/administração & dosagem , Nanopartículas de Magnetita/química , Óxido de Zinco/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Sobrevivência Celular , Daunorrubicina/farmacologia , Daunorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Íons , Nanopartículas de Magnetita/administração & dosagem , Porosidade , Pontos Quânticos/química , Dióxido de Silício/química , Óxido de Zinco/farmacologia
8.
Carbohydr Polym ; 219: 1-11, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151505

RESUMO

Wastewater treatment materials that combine high decontamination performance, ease of use and economic production are highly desirable for practical applications. Herein, we fabricated a low-cost and recyclable bio-adsorbent based on a microbial polysaccharide (salecan) for efficient removal of methyl violet (MV) from wastewater. The success fabrication and the properties (such as thermal stability, microarchitecture, mechanical strength and water uptake) of the adsorbent had been investigated, and the hydrogels were found to have tunable properties by simple adjusting the salecan dose in hydrogel composition. Adsorption data displayed that the adsorption of MV followed the pseudo second-order kinetic model (R2 = 0.99015) and Freundlich isotherm model (R2 = 0.99221) with a maximum adsorption capacity of 178.9 mg/g. Moreover, salecan-based hydrogels showed a good reversibility in adsorption-desorption cycles. These features indicate that salecan-based bio-adsorbent may be a promising device for dye removal from dyeing waste water.


Assuntos
Descontaminação/métodos , Violeta Genciana/química , Hidrogéis/química , Polissacarídeos Bacterianos/química , Purificação da Água/métodos , beta-Glucanas/química , Corantes/química , Cinética , Águas Residuárias/toxicidade , Poluentes Químicos da Água/química
9.
Int J Biol Macromol ; 132: 429-438, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30910674

RESUMO

Adsorbents fabricated with biopolymer are extremely fascinating from the material design aspect, with numerous advantages like excellent biocompatibility, good biodegradability and availability at low cost. In this paper, a novel salecan polysaccharide-based biosorbent was designed for removal of Cd2+ ions from aqueous solutions. The resulting adsorbent was characterized by FTIR, XRD, TGA, SEM, rheology and swelling measurements. Adsorption of Cd2+ onto the salecan biosorbent was evaluated taking into account salecan amount, sorbent dosage, solution pH, initial Cd2+ concentration and contact time. Pseudo-second-order kinetic model and Weber-Morris intra-particle diffusion model well fitted the kinetic results, suggesting chemisorption and intra-particle diffusion as the most probable adsorption mechanism. Meanwhile, the equilibrium adsorption data was nicely described by Langmuir isotherm model with a maximum adsorption capacity of 170.1 mg Cd2+ per gram of sample. Finally, the salecan biosorbent exhibited an excellent reusability and 89.2% of the original sorption ability remained after 6 cycles. The present findings suggest that salecan-based biosorbents have potential for application as a wastewater remediation device.


Assuntos
Cádmio/química , Cádmio/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , beta-Glucanas/química , Adsorção , Cinética
10.
Carbohydr Polym ; 209: 101-110, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30732789

RESUMO

Polysaccharides are an important class of materials that are often exploited in the fields of food, agriculture, biomedical engineering and wastewater treatment owing to their unique and tunable properties. In this work, we utilize an inexpensive and sustainable extracellular polysaccharide salecan (EPS), which is produced by bacterium Agrobacterium sp. ZX09, as a hydrogel matrix, poly(3-sulfopropyl methacrylate potassium salt) (PSM) as side chains to fabricate EPS-grafted-PSM adsorbents through a simple one-pot approach. Scanning electron microscope, X-ray diffraction, Fourier transformed infrared spectroscopy, rheometry and thermogravimetry were conducted to characterize the physicochemical properties of resultant adsorbents. We noticed that EPS not only served as the host chains of network to adjust the water uptake ability of adsorbents, but also endued them with tunable polarity. Further, the adsorption behaviors of developed adsorbents to copper ions (Cu2+) were explored: these gels present high absorption ability for Cu2+ through a chemical adsorption process which well described by Freundlich isotherm and pseudo-second-order kinetic models. In summary, the approach exhibited in this work opens a new avenue to design polysaccharide-based materials for Cu2+ adsorption.

11.
IEEE Trans Vis Comput Graph ; 25(7): 2392-2403, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29994216

RESUMO

In recent years, some biorthogonal Catmull-Clark subdivision wavelet transforms constructed via the lifting scheme have been proposed to speed up processing of geometric models. Thanks to the idea of progressive interpolation, the compression qualities and noise-filtering effects have been improved significantly. However, the reconstruction precision fails to be improved further because many model details are removed and the noise-filtering performance decreases greatly while the noise intensity increases gradually. To deal with this dilemma, a unified Catmull-Clark subdivision based biorthogonal wavelet construction with shape control parameters is presented to process 3D models with sharp-feature constraints. By customizing its local orthogonalizing coefficients for different vertex valences of quadrilateral patches, the novel scheme can greatly strengthen the capability of the model's shape control that is vital for data compression, noise-filtering, etc. Combined with the local and in-place lifting operations, the proposed wavelet transform can dramatically decrease the memory consumption and computation complexity. Both theoretical analysis and numerical experiments show that, compared with the state-of-the-art lifting-based solutions, the proposed wavelet transform achieves higher compression ratio, more stable noise-filtering effects and better progressive transmission quality, not only decreasing the Bits/vertex of 3D meshes and improving the PSNR of reconstructed models, but also reducing the time costs of coding and decoding.

12.
Oncol Lett ; 16(5): 6065-6070, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30344750

RESUMO

Lymph node metastasis is the primary site of metastasis for patients with gallbladder cancer (GBC). Vascular endothelial growth factor-C (VEGF-C) has been implicated in the control of lymphangiogenesis and lymph node metastasis in various malignant tumors. However, the function of circulating VEGF-C is unclear and it is often difficult to evaluate lymph node metastasis and provide a prognosis for GBC. In the present study, ELISA was used to measure the preoperative serum VEGF-C (sVEGF-C) levels of 51 patients with GBC, 15 patients with chronic cholecystitis and 10 healthy volunteers. The results revealed a significantly increased sVEGF-C level in patients with GBC compared with the healthy donors, however no statistically significant difference was identified between patients with GBC and chronic cholecystitis. sVEGF-C levels were associated with lymph node metastasis in GBC and presented a positive correlation with VEGF-C expression and lymphatic vessel density (LVD) in patients with GBC. The mean survival time with high sVEGF-C was significantly reduced compared with low sVEGF-C. A similar result was also observed for VEGF-C expression and LVD. In summary, sVEGF-C levels may predict lymph node metastasis and the prognosis of patients with GBC.

13.
J Nanosci Nanotechnol ; 18(7): 4445-4456, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442618

RESUMO

The dose-dependent toxicity and low specificity against cancerous cells have restricted the clinical use of daunomycin (DNM). Titanium dioxide (TiO2) has been wildly used as an inorganic photodynamic therapy (PDT) agent and drug carrier. To facilitate the targeted drug delivery and combined therapy, in the present study, TiO2-coated Fe3O4 nanoparticles (Fe3O4@TiO2 NPs) were employed to load DNM and the drug-loaded Fe3O4@TiO2-DNM Nps exhibited smart pH-controlled releasing and satisfactory cytotoxicity as well as photocytotocity. The combination of prussian blue staining and fluorescence methods evidenced the effortless cell internalization of the fabricated Fe3O4@TiO2-DNM Nps for the cancer cells. The cell cycle status experiments indicated that the as-prepared nanospheres arrested the S and G2/M periods of the cancer cell proliferation in the dark, and further induced the apoptosis under the irradiation of ultraviolet light. The cell apoptotic results revealed that the apoptosis induced by the Fe3O4@TiO2-DNM Nps was in the early stage. The constructed Fe3O4@TiO2-DNM NPs have been endowed with multifunctions that allow them to selectively deliver combinatorial therapeutic payload and exhibit integrated therapeutic effectiveness to tumors.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Daunorrubicina/farmacologia , Nanosferas , Fotoquimioterapia , Titânio , Antibióticos Antineoplásicos/química , Daunorrubicina/química
14.
J Biomater Appl ; 32(8): 1090-1104, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29357775

RESUMO

Magnetic mesoporous silica nanospheres (MMSN) were prepared and the surface was modified with cancer cell-specific ligand folic acid. Calcium carbonate was then employed as acid-activated gatekeepers to cap the mesopores of the MMSN, namely, MMSN-FA-CaCO3. The formation of the MMSN-FA-CaCO3 was proved by several characterization techniques, viz. transmission electron microscopy, zeta potential measurement, Fourier transform infrared spectroscopy, BET surface area measurement, and UV-Vis spectroscopy. Daunomycin was successfully loaded in the MMSN-FA-CaCO3 and the system exhibited sensitive pH stimuli-responsive release characteristics under blood or tumor microenvironment. Cellular uptake by folate receptor (FR)-overexpressing HeLa cells of the MMSN-FA-CaCO3 was higher than that by non-folated-conjugated ones. Intracellular-uptake studies revealed preferential uptake of these nanoparticles into FR-positive [FR(+)] HeLa than FR-negative [FR(-)]A549 cell lines. DAPI stain experiment showed high apoptotic rate of MMSN-FA-DNM-CaCO3 to HeLa cells. The present data suggest that the CaCO3 coating and folic acid modification of MMSN are able to create a targeted, pH-sensitive template for drug delivery system with application in cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Carbonato de Cálcio/química , Daunorrubicina/administração & dosagem , Preparações de Ação Retardada/química , Ácido Fólico/química , Nanopartículas de Magnetita/química , Dióxido de Silício/química , Células A549 , Antibióticos Antineoplásicos/farmacologia , Daunorrubicina/farmacologia , Preparações de Ação Retardada/metabolismo , Sistemas de Liberação de Medicamentos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/metabolismo , Células HeLa , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
15.
Environ Technol ; 39(21): 2801-2809, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28791916

RESUMO

E-waste is a growing concern around the world and varieties of abandoned E-waste recycling sites, especially in urban area, need to remediate immediately. The impacts of dairy-manure-derived biochars (BCs) on the amelioration of soil properties, the changes in the morphologies as well as the mobility of metals were studied to test their efficacy in immobilization of metals for a potential restoration of vegetation landscape in abandoned E-waste recycling site. The amendment with BCs produced positive effects on bioavailability and mobility reduction for Pb, Cd, Zn and Cu depending on BC ratio and incubation time. The BCs promoted the transformation of species of heavy metals to a more stable fraction, and the metals concentrations in Toxicity Characteristic Leaching Procedure extract declined significantly, especially Pb and Cu. Besides, the BCs ameliorated the substrate with increasing the soil pH, cations exchangeable capacity and available phosphorous, which suggested BC as a potential amendment material for abandoned E-waste recycling sites before restoration of vegetation landscape. Generally, the BC modified by alkaline treatment has a higher efficacy, probably due to increase of specific surface area and porosity as well as the functional groups after alkaline treatment.


Assuntos
Resíduo Eletrônico , Metais Pesados , Poluentes do Solo , Carvão Vegetal , Esterco , Solo
16.
J Photochem Photobiol B ; 173: 606-617, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28697478

RESUMO

DNA polymorphism exerts a fascination on a large scientific community. Without crystallographic structural data, clarification of the binding modes between G-quadruplex (G4) and ligand (complex) is a challenging job. In the present work, three porphyrin compounds with different flexible carbon chains (arms) were designed, synthesized and characterized. Their binding, folding and stabilizing abilities to human telomeric G4 DNA structures were comparatively researched. Positive charges at the end of the flexible carbon chains seem to be favorable for the DNA-porphyrin interactions, which were evidenced by the spectral results and further confirmed by the molecular docking calculations. Biological function analysis demonstrated that these porphyrins show no substantial inhibition to Hela, A549 and BEL 7402 cancer cell lines under dark while exhibit broad inhibition under visible light. This significantly enhanced photocytotoxicity relative to the dark control is an essential property of photochemotherapeutic agents. The feature of the flexible arms emerges as critical influencing factors in the cell photocytotoxicity. Moreover, an ROS-mediated mitochondrial dysfunction pathway was suggested for the cell apoptosis induced by these flexible-armed porphyrins. It is found that the porphyrins with positive charges located at the end of the flexible arms represent an exciting opportunity for photochemotherapeutic anti-cancer drug design.


Assuntos
Apoptose/efeitos dos fármacos , Quadruplex G/efeitos dos fármacos , Porfirinas/toxicidade , Telômero/genética , Células A549 , Apoptose/efeitos da radiação , Sítios de Ligação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Dicroísmo Circular , Quadruplex G/efeitos da radiação , Células HeLa , Humanos , Luz , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Porfirinas/química , Porfirinas/metabolismo , Oxigênio Singlete/análise
17.
Tumour Biol ; 39(3): 1010428317694319, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28345461

RESUMO

The incidence rate of intrahepatic cholangiocarcinoma is rising, and treatment options are limited. Therefore, new biological markers of intrahepatic cholangiocarcinoma are needed. Immunohistochemistry and enzyme-linked immunosorbent assay were applied to analyze the expressions of CD97, CD55, and soluble CD97 in 71 patients with intrahepatic cholangiocarcinoma and 10 patients with hepatolithiasis. CD97 and CD55 were not expressed in hepatolithiatic tissues, but positive expression was observed in 76.1% (54/71) and 70.4% (50/71) of intrahepatic cholangiocarcinoma patients. The univariate analyses indicated that the positive expressions of CD97 and CD55 were related to short intrahepatic cholangiocarcinoma survival of patients (both p = 0.001). Furthermore, CD97 and CD55 expressions and biliary soluble CD97 levels were significantly associated with histological grade (p = 0.004, 0.002, and 0.012, respectively), lymph node metastases (p = 0.020, 0.038, and 0.001, respectively), and venous invasion (p = 0.003, 0.002, and 0.001, respectively). The multivariate analyses indicated that lymph node metastases (hazard ratio: 2.407, p = 0.003), positive CD55 expression (hazard ratio: 4.096, p = 0.003), and biliary soluble CD97 levels (hazard ratio: 2.434, p = 0.002) were independent risk factors for the intrahepatic cholangiocarcinoma survival. The receiver operating characteristic (ROC) curve analysis indicated that when the cutoff values of biliary soluble CD97 were 1.15 U/mL, the diagnostic value for predicting lymph node metastasis had a sensitivity of 87.5% and a specificity of 51.3%. For intrahepatic cholangiocarcinoma patient death within 60 months at a cutoff value of 0.940 U/mL, the diagnostic value sensitivity was 89.3% and the specificity was 93.3%. Biliary soluble CD97 may be a new biological marker for early diagnosis, prediction of lymph node metastasis and poor prognosis, and discovery of a therapeutic target.


Assuntos
Antígenos CD/biossíntese , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Biomarcadores Tumorais/metabolismo , Antígenos CD55/biossíntese , Colangiocarcinoma/patologia , Idoso , Bile/metabolismo , Neoplasias dos Ductos Biliares/mortalidade , Colangiocarcinoma/mortalidade , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Receptores Acoplados a Proteínas-G , Sensibilidade e Especificidade
18.
J Biomater Appl ; 31(2): 261-72, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27288463

RESUMO

The clinical use of daunomycin is restricted by dose-dependent toxicity and low specificity against cancer cells. In the present study, modified superparamagnetic iron oxide nanoparticles were employed to load daunomycin and the drug-loaded nanospheres exhibited satisfactory size and smart pH-responsive release. The cellular uptake efficiency, targeted cell accumulation, and cell cytotoxicity experimental results proved that the superparamagnetic iron oxide nanoparticle-loading process brings high drug targeting without decreasing the cytotoxicity of daunomycin. Moreover, a new concern for the evaluation of nanophase drug delivery's effects was considered, with monitoring the interactions between human serum albumin and the drug-loaded nanospheres. Results from the multispectroscopic techniques and molecular modeling calculation elucidate that the drug delivery has detectable deleterious effects on the frame conformation of protein, which may affect its physiological function.


Assuntos
Daunorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Nanopartículas de Magnetita/química , Sobrevivência Celular , Doxorrubicina/química , Liberação Controlada de Fármacos , Células HeLa , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Simulação de Acoplamento Molecular , Nanosferas/química , Albumina Sérica/química
19.
Tumour Biol ; 36(8): 6305-12, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25801241

RESUMO

Gallbladder carcinoma (GBC) is the most common cancer of the biliary tract. Lymph node metastasis (LNM) is the major diffusion route of GBC and is a prognosis factor. The aim of study was to assess the potential of the serum VEGF-C and VEGF-D (sVEGF-C/D) levels to predict the presence of LNM and the survival of GBC patients. The preoperative sVEGF-C/D levels of 31 patients with GBC, 10 patients with cholesterol polyps, and 10 healthy volunteers were measured by enzyme-linked immunoadsorbent assay (ELISA). The sVEGF-C/D levels of patients with GBC were significantly higher than those of people with healthy gallbladders (p < 0.001 and p = 0.001, respectively) and cholesterol polyp (p = 0.032 and p = 0.004, respectively). In GBC, the sVEGF-C levels were associated with LNM (p = 0.011), distant metastasis (p = 0.018), and stage (p = 0.045), but the sVEGF-D levels had a significant association with the tumor depth (p = 0.001), LNM (p = 0.001), distant metastasis (p = 0.047), and stage (p = 0.002). The sVEGF-C/D diagnostic values for the presence of GBC were sensitivity of 71.0 and 74.2 % and specificity of 80.0 and 85.0 %, respectively. With respect to the diagnosis of LNM, the diagnostic values of sVEGF-C/D were as follows: sensitivity 81.2 and 87.5 % and specificity 73.3 and 80.0 %, respectively. The mean survival time with high sVEGF-C was significantly shorter than that with low sVEGF-C (p < 0.001), which was also true for low sVEGF-D (p = 0.032). The preoperative sVEGF-C/D levels might be reliable biomarkers for the presence of disease and LNM in patients with GBC. The sVEGF-C/D levels may be prognosis factors that can predict a poor outcome for GBC patients.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma/sangue , Neoplasias da Vesícula Biliar/sangue , Fator C de Crescimento do Endotélio Vascular/sangue , Fator D de Crescimento do Endotélio Vascular/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Carcinoma/cirurgia , Feminino , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prognóstico
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