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1.
Materials (Basel) ; 15(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36556715

RESUMO

Additive manufacturing technology has been widely used in aviation, aerospace, automobiles and other fields due to the fact that near-net-shaped components with unprecedented geometric freedom can be fabricated. Additively manufactured aluminum alloy has received a lot of attention, due to its excellent material properties. However, the finished surface of additively manufactured aluminum alloy with nanoscale surface roughness is quite challenging and rarely addressed. In this paper, a novel machining technology known as ultrasonic elliptical vibration-assisted cutting (UEVC) was adopted to suppress the generation of cracks, improve the surface integrity and reduce tool wear during the ultra-precision machining of selective laser melting (SLM) additively manufactured AlSi10Mg alloy. The experimental results revealed that, in the conventional cutting (CC) process, surface defects, such as particles, pores and grooves, appeared on the machined surface, and the machined surface rapidly deteriorated with the increase in cumulative cutting area. In contrast, an almost flawless machined surface was obtained in the UEVC process, and its roughness value was less than 10 nm. Moreover, the tool wear of the CC tool was remarkably greater than that of the UEVC tool, and the standard flank wear width of the CC tool was more than twice that of the UEVC tool. Therefore, the UEVC technology is considered to be a feasible method for the ultra-precision machining of SLM additively manufactured AlSi10Mg alloy.

2.
J Comput Biol ; 28(1): 89-98, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32757947

RESUMO

Proper evaluation of the relevant clinical factors for the prognosis of breast cancer is particularly important in the selection of appropriate therapeutic strategies. To further screen and identify the clinically significant factors associated with breast cancer, the Cox risk regression model analysis was performed in this study. The follow-up data of intact breast cancer patients were downloaded from METABRIC (Molecular Taxonomy of Breast Cancer International Consortium) database, and the prognostic factors correlated with radiotherapy factors were screened using the Cox risk regression model analysis of prognostic factors. The response of different clinical features to radiotherapy was also evaluated by survival prognosis analysis and prediction. A total of 1980 breast cancer patients were enrolled in this study, including 1173 patients who received the radiotherapy treatment and 807 patients without radiotherapy treatment. To further study the correlation between the clinical prognostic factors and the overall survival, the single factor and multivariate Cox regression analysis were performed, and the clinical prognostic factors implied that the patients with age <60 years, receiving radiotherapy, grade 1, stage 0-1, or human epidermal growth factor receptor 2 (HER2) negative had a better overall clinical survival. The association analysis of the radiotherapy treatment and the clinical prognostic factors implied that the patients with younger age, stage lower, or HER2 negative showed a better overall clinical survival, and the patients who received radiotherapy had a better 3-year survival probability and 5-year survival probability. Screening and identifying the clinically significant factors associated with breast cancer can help predict the risk of disease. Age, stage, or HER2 status was the prognostic factors correlated with radiotherapy treatment.


Assuntos
Neoplasias da Mama/epidemiologia , Receptor ErbB-2/genética , Fatores Etários , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Feminino , Humanos , Gradação de Tumores/estatística & dados numéricos , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia/estatística & dados numéricos
3.
J Biomater Sci Polym Ed ; 31(12): 1538-1551, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32362234

RESUMO

The long circulation time and targeting drug delivery at tumor sites are still the main challenges of nanodrug delivery systems for antitumor activity. Herein, a cancer cell membrane-coated biomimetic nanodrug delivery system was fabricated. The paclitaxel (PTX)-loaded poly(lactic acid) (PLA) nanoparticles (PPNs) were used as the inner cores and 4T1 cancer cell membranes were coated on the surface of PPNs as the outer shells. The biomimetic platform was noted as CPPNs. The CPPNs exhibited proper sizes for the enhanced permeability and retention (EPR) effect and could maintain stability in a simulated physiological environment. The CPPNs exhibited a better antitumor effect than PPNs and free PTX in vitro. Moreover, due to the immune escape and homologous targeting abilities endowed by the cancer cell membrane coating, the CPPNs could efficiently accumulate and long-term exist at tumor sites. In the orthotopic 4T1 breast cancer mouse model, the CPPNs effectively inhibited the progression of tumor by increasing the apoptosis and necrosis areas within tumor tissues. In addition, the toxic side effects of PTX was also alleviated in the CPPNs group. As a result, CPPNs can be a promising biomimetic nanodrug delivery system for the enhanced and targeted therapy of breast cancer.


Assuntos
Neoplasias da Mama , Nanopartículas , Animais , Biomimética , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Membrana Celular , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Camundongos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico
4.
J Gene Med ; 22(3): e3141, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31697007

RESUMO

BACKGROUND: The present study aimed to identify key molecular targets of breast cancer for targeted treatment and to improve the survival rate. METHODS: Overlapped difference expression genes in three datasets were identified in a weighted gene co-expression network analysis (WGCNA) module and MetaDE.ES analysis. Combined with the prognosis information [time, death, status and relative survival (RS)] in GSE42568, single-factor Cox regression analysis was used to screen the genes that were significantly related to the prognosis in the target gene set. RESULTS: In total, 13 optimal gene combinations with a significantly correlated prognosis were obtained, including SSPN, NELL2, AGTR1, NRIP3, IKZF2, NAT1, CXCL12, NPY1R, PRAME, PPP1R1B, CRISP3, NMU and GSTP1. In addition, there was a significant correlation between the samples given by the prognostic prediction system and the validation dataset (GSE20685 and TCGA), with p values of 0.0299 in GSE20685 and 1.461 × 10-5 in TCGA, and an area under the receiver operating characteristic of 0.942 and 0.923, respectively. RS-related differentially expressed genes between high- and low-risk groups were significantly related to biological processes such as cell period and the hormone stimulation response, and were also significantly involved in KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways such as cell period, the peroxisome proliferator-activated receptor signaling pathway and the cancer pathway. CONCLUSIONS: By predicting the survival risk of breast cancer patients based on the 13 optimal genes, high-risk patients would be detected early. Accordingly, this would help in the formulation of an appropriate treatment plan for patients.


Assuntos
Neoplasias da Mama/genética , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Predisposição Genética para Doença , Biomarcadores Tumorais/genética , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Prognóstico
5.
Dalton Trans ; 48(16): 5450-5458, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30957800

RESUMO

Six metal-organic frameworks with the combination of a novel tripodal ligand tris[4-(1H-imidazol-1-yl)phenyl]phosphine oxide (tipo) and different polycarboxylates, namely [Zn2(bpdc)2(tipo)(H2O)]·5H2O (1), [Cd(tipo)2][Cd2(bdc)3]·4H2O (2), [Cd2(ndc)2(tipo)2]·3H2O (3), [Cd2(bpedc)2(tipo)2]·15H2O (4), [Cd2(hfdc)2(tipo)2]·10H2O (5) and [Ni2(tipo)2(bpedc)(H2O)4]·2NO3·2DMF (6), were synthesized and structurally characterized. Compound 1 featured a 2D → 3D parallel polycatenation of a 3,3,4-connected net with an unusual 4 degrees of catenation and an index of separation of 2. Compound 2 showed an unprecedented polycatenation of charged networks 2D kgd and 3D pcu constructed by different organic ligands. Compound 3 exhibited a combination of a 2D → 3D parallel polycatenation of the sql net and polythreading. Compound 4 featured a 4-fold interpenetration of a 3,5-connected 3,5T1 net. Compound 5 displayed an unusual 2-fold interpenetration of the sdd net. Compound 6 presented a 2-fold interpenetration of the 3,4-connected bey net with a cationic framework. The luminescence properties of 1-5 in the solid state were investigated. Also, compound 6 showed a tendency for rapid selective dye capture and highly efficient Cr2O72- removal from aqueous solution.

6.
Dalton Trans ; 46(43): 14988-14994, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29048438

RESUMO

A unique microporous anionic metal-organic framework, namely [Zn2(btb)2(bbis)](Me2NH2)2·6DMF (1), has been synthesized and structurally characterized [bbis = bis(4-benzylimidazol-ylphenyl)sulfone and H3btb = 4,4',4''-benzene-1,3,5-triyltribenzoic acid]. This compound exhibits a 4-fold interpenetrated anionic framework with ins topology. The post-synthetic cation exchange of 1 with Eu3+, Tb3+, Dy3+ and Sm3+ afforded lanthanide(iii)-loaded materials. Eu3+@1 and Tb3+@1 can be used as the potential luminescent probes in nitrobenzene. The adsorption behavior of 1 towards organic dyes was investigated, revealing rapid and selective separation of methylene blue.

7.
Dalton Trans ; 45(27): 11129-36, 2016 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-27327414

RESUMO

Core-shell-shell heterostructures of α-NaLuF4:Yb/Er@NaLuF4:Yb@MF2 (M = Ca, Sr, Ba) have been successfully fabricated via the thermal decomposition method. Upconversion nanoparticles (UCNPs) were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), upconversion luminescence (UCL) spectroscopy, etc. Under 980 nm excitation, the emission intensities of the UCNPs are remarkably enhanced after coating the MF2 (M = Ca, Sr, and Ba) shell. Among these samples, CaF2 coated UCNPs show the strongest overall emission, while BaF2 coated UCNPs exhibit the longest lifetime. These results demonstrate that alkaline earth metal fluorides are ideal materials to improve the UCL properties. Meanwhile, although the lattice mismatch between the ternary NaREF4 core and the binary MF2 (M = Sr and Ba) shell is relatively large, the successfully synthesized NaLuF4:Yb/Er@NaLuF4:Yb@MF2 indicates a new outlook on the fabrication of heterostructural core-shell UCNPs.

8.
Dalton Trans ; 39(30): 7091-7, 2010 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-20577698

RESUMO

4-Triazolyl-dipicolinic acids, prepared efficiently by CuAAC, proved to act as efficient antennae for optical lanthanide probes containing Eu(3+) or Tb(3+), under linear and non linear excitations (one, two and three photons provided by laser induced luminescence). The versatility offered by the substitution of the triazole subunit is, in addition, useful for covalent linkage to slide glass providing luminescent films.


Assuntos
Európio/química , Corantes Fluorescentes/química , Compostos Organometálicos/química , Ácidos Picolínicos/química , Térbio/química , Corantes Fluorescentes/síntese química , Estrutura Molecular , Compostos Organometálicos/síntese química
9.
Dalton Trans ; (13): 2406-14, 2009 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-19290375

RESUMO

A beta-diketone ligand 4,4,5,5,5-pentafluoro-1-(2-naphthyl)-1,3-butanedione (Hpfnp), which contains a pentafluoroalkyl chain, was synthesized as the main sensitizer for synthesizing new near-infrared (NIR) luminescent Ln(pfnp)(3)phen (phen = 1,10-phenanthroline) (Ln = Er, Nd, Yb, Sm) complexes. At the same time, a series of lanthanide complexes covalently bonded to xerogels by the ligand 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline (phen-Si) were synthesized in situvia a sol-gel process. [The obtained materials are denoted as xerogel-bonded Ln complexes (Ln = Er, Nd, Yb, Sm).] The single crystal structures of the Ln(pfnp)(3)phen complexes were determined. The properties of these complexes and the corresponding xerogel materials were investigated by Fourier-transform infrared (FTIR), diffuse reflectance (DR), and field-emission scanning electron microscopy (FE-SEM). After ligand-mediated excitation of these complexes and the corresponding xerogel materials they all show the characteristic NIR luminescence of the corresponding Ln(3+) ion. This is attributed to efficient energy transfer from the ligands to the Ln(3+) ion (the so-called "antenna effect").

10.
Langmuir ; 24(10): 5500-7, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18412375

RESUMO

A novel mesoporous material covalently bonded with 8-hydroxyquinoline (HQ) was synthesized (designated as Q-SBA-15). The 5-formyl-8-hydroxyquinoline grafted to (3-aminopropyl)triethoxysilane, that is, alkoxysilane modified 8-hydroxyquinoline (Q-Si), was used as one of the precursors for the preparation of the Q-SBA-15 material. On the basis of the other function of the Q-Si of coordinating to lanthanide (Ln) ions, for the first time, the LnQ 3 complexes (Ln = Er, Nd, Yb) have been covalently bonded to the SBA-15 materials. The derivative materials, denoted as LnQ 3-SBA-15, were characterized by field emission scanning electron microscopy (FE-SEM), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-desorption, and fluorescence spectra. Upon excitation at the ligands absorption bands, all of these materials show the characteristic near-infrared (NIR) luminescence of the corresponding lanthanide ions through the intramolecular energy transfer from the ligands to the lanthanide ions. The NIR luminescence of these mesoporous materials was compared with that of the corresponding pure LnQ 3 complexes and discussed in detail.

11.
J Phys Chem B ; 110(14): 7249-58, 2006 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-16599494

RESUMO

The near-infrared (NIR) luminescent lanthanide ions, such as Er(III), Nd(III), and Yb(III), have been paid much attention for the potential use in the optical communications or laser systems. For the first time, the NIR-luminescent Ln(dbm)(3)phen complexes have been covalently bonded to the ordered mesoporous materials MCM-41 and SBA-15 via a functionalized phen group phen-Si (phen-Si = 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline; dbm = dibenzoylmethanate; Ln = Er, Nd, Yb). The synthesis parameters X = 12 and Y = 6 h (X denotes Ln(dbm)(3)(H(2)O)(2)/phen-MCM-41 molar ratio or Ln(dbm)(3)(H(2)O)(2)/phen-SBA-15 molar ratio and Y is the reaction time for the ligand exchange reaction; phen-MCM-41 and phen-SBA-15 are phen-functionalized MCM-41 and SBA-15 mesoporous materials, respectively) were selected through a systematic and comparative study. The derivative materials, denoted as Ln(dbm)(3)phen-MCM-41 and Ln(dbm)(3)phen-SBA-15 (Ln = Er, Nd, Yb), were characterized by powder X-ray diffraction, nitrogen adsorption/desorption, Fourier transform infrared (FT-IR), elemental analysis, and fluorescence spectra. Upon excitation of the ligands absorption bands, all these materials show the characteristic NIR luminescence of the corresponding lanthanide ions through the intramolecular energy transfer from the ligands to the lanthanide ions. The excellent NIR-luminescent properties enable these mesoporous materials to have potential uses in optical amplifiers (operating at 1.3 or 1.5 mum), laser systems, or medical diagnostics. In addition, the Ln(dbm)(3)phen-SBA-15 materials show an overall increase in relative luminescent intensity and lifetime compared to the Ln(dbm)(3)phen-MCM-41 materials, which was explained by the comparison of the lanthanide ion content and the pore structures of the two kinds of mesoporous materials in detail.

12.
J Phys Chem B ; 109(32): 15278-87, 2005 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-16852935

RESUMO

A novel mesoporous SBA-15 type of hybrid material (phen-SBA-15) covalently bonded with 1,10-phenanthroline (phen) ligand was synthesized by co-condensation of tetraethoxysilane (TEOS) and the chelate ligand 5-[N,N-bis-3-(triethoxysilyl)propyl]ureyl-1,10-phenanthroline (phen-Si) in the presence of Pluronic P123 surfactant as a template. The preservation of the chelate ligand structure during the hydrothermal synthesis and the surfactant extraction process was confirmed by Fourier transform infrared (FTIR) and (29)Si MAS NMR spectroscopies. SBA-15 consisting of the highly luminescent ternary complex Eu(TTA)(3)phen (TTA = 2-thenoyltrifluoroacetone) covalently bonded to a silica-based network, which was designated as Eu(TTA)(3)phen-SBA-15, was obtained by introducing the Eu(TTA)(3).2H(2)O complex into the hybrid materials via a ligand exchange reaction. XRD, TEM, and N(2) adsorption measurements were employed to characterize the mesostructure of Eu(TTA)(3)phen-SBA-15. For comparison, SBA-15 doped with Eu(TTA)(3).2H(2)O and Eu(TTA)(3)phen complexes and SBA-15 covalently bonded with a binary europium complex with phen ligand were also synthesized, and were named SBA-15/Eu(TTA)(3), SBA-15/Eu(TTA)(3)phen, and Eu-phen-SBA-15, respectively. The detailed luminescence studies on all the materials showed that, compared with the doping sample SBA-15/Eu(TTA)(3)phen and binary europium complex functionalized sample Eu-phen-SBA-15, the Eu(TTA)(3)phen-SBA-15 mesoporous hybrid material exhibited higher luminescence intensity and emission quantum efficiency. Thermogravimetric analysis on Eu(TTA)(3)phen-SBA-15 demonstrated that the thermal stability of the lanthanide complex was evidently improved as it was covalently bonded to the mesoporous SBA-15 matrix.

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