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1.
J Biochem Mol Toxicol ; 34(11): e22562, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32659858

RESUMO

The in vivo toxicity of Gd2 O3 :Eu3+ nanoparticles (NPs) used as dual-modal nanoprobes for molecular imaging has not been studied, and the corresponding molecular mechanism of immunotoxicity remains unknown. In this study, we investigated the cytotoxicity, in vitro apoptosis, and in vivo immunotoxicity of Gd2 O3 :Eu3+ NPs. The NPs showed little immunotoxicity to BALB/c mice. We explored the possible role of the phosphoinositide 3-kinase (PI3K) signaling pathway and found that reactive oxygen species could act as secondary messengers in cellular signaling, inhibiting PI3K expression in the liver. The immune suppression caused by PI3K inhibition helped the mice adapt to stress. The immunotoxicities caused by Gd2 O3 :Eu3+ and gadodiamide, a commonly used contrast agent, were not significantly different, and the mice were able to tolerate the immunotoxicity caused Gd2 O3 :Eu3+ NPs in vitro and in vivo experiments. The results suggest that Gd2 O3 :Eu3+ NPs are sufficiently biocompatible to be used safely in preclinical applications and show promise as bio-imaging agents. Moreover, the in vivo molecular mechanism of immunotoxicity caused by the Gd2 O3 :Eu3+ NPs provides a platform for further research on the immunotoxicity of nano-sized biomaterials.


Assuntos
Európio/química , Gadolínio/química , Nanopartículas Metálicas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
2.
Water Sci Technol ; 82(11): 2296-2303, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33339785

RESUMO

In this study, the removal effect of free and immobilized bacteria on crude oil was determined. Sodium alginate and polyvinyl alcohol were used as embedding agent, and ramie was modified as an adsorbent to immobilize free bacteria. The conditions for preparing immobilized pellets were optimized using the response surface method, and the best combination was simulated and obtained by Design-Expert 8.0. The best degradation rate of immobilized bacteria was 75.52%. The degradation by free bacteria and immobilized bacteria showed that the selected microorganisms had a good degradation effect on petroleum hydrocarbons.


Assuntos
Poluição por Petróleo , Petróleo , Bactérias , Biodegradação Ambiental , Hidrocarbonetos
3.
Bioorg Med Chem ; 27(1): 133-143, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30482547

RESUMO

A novel scaffold of arylpiperazine derivatives was discovered as potent androgen receptor (AR) antagonist through rational drug designation based on our pre-work, leading to the discovery of a series of new antiproliferative compounds. Compounds 10, 16, 27, 29 and 31 exhibited relatively strong antagonistic potency against AR and exhibited potent AR binding affinities, while compounds 5, 6, 10, 14, 16, 19, 21, 27 and 31 exhibited strong cytotoxic activities against LNCaP cells (AR-rich) as well as also displayed the higher activities than finasteride toward PC-3 (AR-deficient) and DU145 (AR-deficient). Docking study suggested that the most potent antagonist 16 mainly bind to AR ligand binding pocket (LBP) site through hydrogen bonding interactions. The structure-activity relationship (SAR) of these designed arylpiperazine derivatives was rationally explored and discussed. These results indicated that the novel scaffold compounds demonstrated a step towards the development of novel and improved AR antagonists, and promising candidates for future development were identified.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Piperazinas/farmacologia , Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Relação Estrutura-Atividade
4.
Bioorg Med Chem Lett ; 28(9): 1534-1539, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29615343

RESUMO

For the development of potential anti-prostate cancer agents, 24 kinds of novel naftopidil-based arylpiperazine derivatives have been synthesized and characterized by spectroscopic methods. Their antitumor activities were evaluated against several classical prostate cancer cell lines including PC-3, LNCaP, and DU145. Among all the compounds, 9, 13, 17, 21 and 27 showed strong cytotoxic activities against DU145 cells (IC50 < 1 µM). Further testing confirmed that compound 17 inhibited the growth of DU145 cells by inducing cell cycle arrest at G0/G1 phase. Besides, antagonistic activities of compounds (9, 13, 17, 21 and 27) towards a1-ARs (α1A, α1B, and α1D) were further evaluated using dual-luciferase reporter assays, and the compounds 13 and 17 exhibited better a1-ARs subtype selectivity. The structure-activity relationship (SAR) of these developed arylpiperazine derivatives was rationally discussed. Taken together, these results suggested that further development of such compounds may be of great interest.


Assuntos
Antineoplásicos/farmacologia , Naftalenos/farmacologia , Piperazina/farmacologia , Piperazinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Naftalenos/química , Piperazina/síntese química , Piperazina/química , Piperazinas/química , Relação Estrutura-Atividade
5.
Nanotechnology ; 29(29): 295604, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29715197

RESUMO

The fabrication of inorganic fullerene-like nanoparticles (IFNPs) is an attractive idea due to their unique structures and various potential applications. To date, IFNPs have been made from numerous compounds with layered two-dimensional structures, based on various synthetic methods. Here we have demonstrated for the first time that inorganic fullerene-like molybdenum selenide nanoparticles (MoSe2 IFNPs) can be synthesized by laser ablating a molybdenum selenide target in 30 vol % ethanol/water mixture at ambient temperature and pressure. The formation mechanism was proposed to elucidate the production of MoSe2 IFNPs in the process of laser ablation in liquids (LAL). The appropriate solvent facilitates the condensation of the plasma plume created by LAL to planar MoSe2. Then, laser-induced high temperature and high pressure lead to the formation of a vacancy in the planar MoSe2, causing the generation of nucleation and growth of the MoSe2 IFNPs. In addition, a CCK-8 (cell counting kit-8) assay and a cell viability assay were performed to examine the cytotoxic behavior and the effect on cell viability of MoSe2 IFNPs. The results show that MoSe2 IFNPs are reasonably nontoxic and biocompatible with the given cells, showing they have significant potential in biomedical applications.

6.
Water Sci Technol ; 78(12): 2626-2638, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30767927

RESUMO

The aim of this study was to isolate hydrocarbons-degrading bacteria for treatment of oily wastewater from long-standing petroleum-polluted sediments in Bohai Bay, China. Six hydrocarbons-degrading bacteria were screened and identified as Pseudomonas sp. and Bacillus sp. A new approach using a combination of various bacterial species in petroleum biodegradation was proposed and evaluated for its degradation characteristics. Gas chromatography-flame ionization detection (GC-FID) analysis showed that mixed bacterial agents (YJ01) degraded 80.64% of crude oil and 76.30% of crude oil alkanes, exhibiting good biodegradation effect. Besides, after 14 days of culture, the biodegradation assessment markers, pristane and phytane, showed significant degradation rates of 46.75% and 78.23%, respectively. Kinetic analysis indicated that the degradation trends followed a single first-order kinetics model and the degradation half-life (t1/2) of 15 g/L crude oil was significantly shorter (5.48 days). These results indicated that YJ01 could degrade a wider range of hydrocarbons as well as some recalcitrant hydrocarbon components, and can be applied for bioremediation and treatment of oil-contaminated environment.


Assuntos
Biodegradação Ambiental , Petróleo/metabolismo , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismo , China , Hidrocarbonetos , Cinética , Petróleo/análise , Águas Residuárias/química , Microbiologia da Água , Poluentes Químicos da Água/análise
7.
J Xray Sci Technol ; 24(6): 837-853, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27612048

RESUMO

Dynamic cerebral perfusion x-ray computed tomography (PCT) imaging has been advocated to quantitatively and qualitatively assess hemodynamic parameters in the diagnosis of acute stroke or chronic cerebrovascular diseases. However, the associated radiation dose is a significant concern to patients due to its dynamic scan protocol. To address this issue, in this paper we propose an image restoration method by utilizing coupled dictionary learning (CDL) scheme to yield clinically acceptable PCT images with low-dose data acquisition. Specifically, in the present CDL scheme, the 2D background information from the average of the baseline time frames of low-dose unenhanced CT images and the 3D enhancement information from normal-dose sequential cerebral PCT images are exploited to train the dictionary atoms respectively. After getting the two trained dictionaries, we couple them to represent the desired PCT images as spatio-temporal prior in objective function construction. Finally, the low-dose dynamic cerebral PCT images are restored by using a general DL image processing. To get a robust solution, the objective function is solved by using a modified dictionary learning based image restoration algorithm. The experimental results on clinical data show that the present method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the state-of-the-art methods.


Assuntos
Circulação Cerebrovascular , Processamento de Imagem Assistida por Computador/métodos , Imagem de Perfusão/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Aprendizado de Máquina
8.
Langmuir ; 30(43): 13005-13, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25289961

RESUMO

Monoclinic Gd2O3:Eu(3+) nanoparticles (NPs) possess favorable magnetic and optical properties for biomedical application. However, how to obtain small enough NPs still remains a challenge. Here we combined the standard solid-state reaction with the laser ablation in liquids (LAL) technique to fabricate sub-10 nm monoclinic Gd2O3:Eu(3+) NPs and explained their formation mechanism. The obtained Gd2O3:Eu(3+) NPs exhibit bright red fluorescence emission and can be successfully used as fluorescence probe for cells imaging. In vitro and in vivo magnetic resonance imaging (MRI) studies show that the product can also serve as MRI good contrast agent. Then, we systematically investigated the nanotoxicity including cell viability, apoptosis in vitro, as well as the immunotoxicity and pharmacokinetics assays in vivo. This investigation provides a platform for the fabrication of ultrafine monoclinic Gd2O3:Eu(3+) NPs and evaluation of their efficiency and safety in preclinical application.


Assuntos
Európio/química , Gadolínio/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas Metálicas/química , Imagem Óptica/métodos , Tamanho da Partícula , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Feminino , Gadolínio/farmacocinética , Gadolínio/toxicidade , Masculino , Camundongos , Modelos Moleculares , Conformação Molecular , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
9.
Int J Mol Sci ; 15(8): 13649-62, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25105724

RESUMO

We have successfully synthesized SiO2@(Y0.5Gd0.45Eu0.05)2O3 nanocomposites as a potential dual-modality nanoprobe for molecular imaging in vitro. However, their immunotoxicity assessment in vivo remains unknown. In this article, the in vitro biocompatibility of our dual-modality nanoprobes was assayed in terms of cell viability and apoptosis. In vivo immunotoxicity was investigated by monitoring the generation of reactive oxygen species (ROS), cluster of differentiation (CD) markers and cytokines in Balb/c mice. The data show that the in vitro biocompatibility was satisfactory. In addition, the immunotoxicity data revealed there are no significant changes in the expression levels of CD11b and CD71 between the nanoprobe group and the Gd in a diethylenetriaminepentaacetic acid (DTPA) chelator (Gd-DTPA) group 24 h after injection in Balb/c mice (p>0.05). Importantly, there are significant differences in the expression levels of CD206 and CD25 as well as the secretion of IL-4 and the generation of ROS 24 h after injection (p<0.05). Transmission electron microscopy (TEM) images showed that few nanoprobes were localized in the phagosomes of liver and lung. In conclusion, the toxic effects of our nanoprobes may mainly result from the aggregation of particles in phagosomes. This accumulation may damage the microstructure of the cells and generate oxidative stress reactions that further stimulate the immune response. Therefore, it is important to evaluate the in vivo immunotoxicity of these rare earth-based biomaterials at the molecular level before molecular imaging in vivo.


Assuntos
Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/toxicidade , Nanocompostos/toxicidade , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Európio/química , Európio/metabolismo , Európio/toxicidade , Gadolínio/química , Gadolínio/metabolismo , Gadolínio/toxicidade , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Compostos Heterocíclicos/toxicidade , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-4/metabolismo , Lectinas Tipo C/metabolismo , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/química , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Compostos Organometálicos/toxicidade , Óxidos/química , Óxidos/metabolismo , Óxidos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Receptores de Superfície Celular/metabolismo , Dióxido de Silício/metabolismo , Distribuição Tecidual , Ítrio/química , Ítrio/metabolismo , Ítrio/toxicidade
10.
J AOAC Int ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902942

RESUMO

BACKGROUND: AnticFast® Beta-lactams & Tetracyclines Combo Test Kit is a qualitative two-step (2 min + 5 min) rapid lateral flow assay to detect ß-lactam (penicillins and cephalosporins) and tetracycline antibiotic residues in raw commingled cows' milk. OBJECTIVE: The method performance was evaluated according to Commission Implementing Regulation 2021/808 and Community Reference Laboratories Residues Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines and submitted for AOAC Performance Tested Methods  SM certification. METHODS: The AnticFast Beta-lactams & Tetracyclines Combo Test Kit was evaluated for detection capability (CCß), selectivity, false-positive results, repeatability, robustness, suitability for various milk types and milk compositions, milks from various species, and test kit consistency and stability. Samples included milks spiked at concentrations bracketing the EU Maximum Residue Limits (MRLs) for ß-lactams and tetracyclines as well as bulk farm and tanker milks. RESULTS: The AnticFast Beta-lactams & Tetracyclines Combo Test Kit is specific for the detection of residues of ß-lactams and tetracyclines in milk and does not detect residues from other antibiotic families. Interference was seen with clavulanic acid, a ß-lactamase inhibitor, which was expected. The test can detect (minimum a 95% detection) all residues of ß-lactams (penicillins and cephalosporins) and tetracyclines (parent drugs and their 4-epimers) present on the EU-MRL list for milk at their respective MRL except for desfuroylceftiofur and cephalexin, with a 95% detection only above the MRL. No false positives were detected in 599 (305 blank farm and 301 tanker load) samples tested on both channels. Five real positives were detected and confirmed on the tetracycline channel for the blank farm milk, and two positives were detected and confirmed on the ß-lactam channel for the tanker samples. Robustness testing indicated that the detection in high protein raw cows' milk and heat-treated milk types (UHT, sterilized and reconstituted milk powder) may be slightly hampered. For substances with a detection capability well below the MRL this interference is not causing problems since detection at MRL remains guaranteed, but care should be taken for substances with a CCß at or near their MRL. Diminished sample flow was seen for high fat raw cows' milk and for all other cows' milk types other than raw milk and blank ewes' milk, so sample flow should always be verified for these milk types. CONCLUSIONS: Results of this validation show that the AnticFast Beta-lactams & Tetracyclines Combo Test Kit is a reliable test for rapid screening of raw cows' milk for residues of ß-lactam and tetracycline antibiotics. HIGHLIGHTS: The AnticFast Beta-lactams & Tetracycline Combo Test Kit is an easy, reliable, robust and highly specific test for screening of ß-lactam (penicillins and cephalosporins) and tetracycline antibiotic residues in milk with incubation at room temperature. In raw cows' milk, all tetracyclines are detected below 10 µg/kg.

11.
Phys Chem Chem Phys ; 15(29): 12235-40, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23771105

RESUMO

Gadolinium oxide (Gd2O3), which can be used as a T1-weighted magnetic resonance imaging (MRI) contrast agent, has attracted intense attention in recent years. In this paper, ligand-free monoclinic Gd2O3 nanocrystals of 7.1 nm in diameter are synthesized by a simple and green approach, namely microsecond laser ablation of a gadolinium (Gd) target in deionized water. These nanocrystals obtain high r1 relaxivity of 5.53 s(-1) mM(-1), and their low toxicity was demonstrated by the cell viability of S18 cells and apoptosis in RAW264.7 cells. In vitro and in vivo MR images show these particles to be good T1-weighted MRI contrast agents. Base on the experimental results and theoretical analysis, we suggest that the purity of the Gd2O3 contributes to its high r1 relaxivity value, while the low toxicity is due to its good crystallinity. These findings show that laser ablation in liquid (LAL) is a promising strategy to synthesize ligand-free monoclinic Gd2O3 nanocrystals for use as high efficient T1-weighted MRI contrast agents.


Assuntos
Gadolínio/química , Animais , Apoptose/efeitos dos fármacos , Carcinoma , Linhagem Celular , Meios de Contraste/química , Meios de Contraste/toxicidade , Humanos , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico por imagem , Radiografia , Transplante Heterólogo
12.
Water Sci Technol ; 68(1): 209-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23823557

RESUMO

Ethylenediaminetetraacetic dianhydride (EDTAD)-modified magnetic-Fe3O4 chitosan (EMC), prepared using the cross-link agent glutaraldehyde and chemicals Fe3O4, chitosan, and EDTAD, was used to compare the adsorption of methylene blue (MB) with magnetic chitosan (MC). The composite structure was confirmed by multiple characterization techniques, including scanning electron microscopy (SEM), X-ray powder diffraction, Fourier transform infrared spectroscopy (FTIR), and potentiometric titration methods. The characterization results suggest that Fe3O4 particles successfully bound on the surface of chitosan, and the EDTAD thoroughly modified the MC. Furthermore, EMC had more amino, carboxyl, and hydroxy groups than typical MC. Adsorption conditions, such as pH values, initial concentrations of MB, reaction temperature, and contact time were systematically examined. In comparison, the maximum adsorption capacity of EMC was approximately twice as much as that of MC. The recovery efficiency for EMC was >80% using 0.1 M HCl as an eluent solution. Therefore, the results reported herein indicate that EMC is very attractive and imply a practical application for dye wastewater treatment.


Assuntos
Quitosana/química , Corantes/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Magnetismo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
J AOAC Int ; 106(5): 1197-1208, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37171872

RESUMO

BACKGROUND: AnticFast® Beta-Lactams Rapid Test Kit is a qualitative two-step (2 min + 5 min) rapid lateral flow assay to detect ß-lactam (penicillins and cephalosporins) antibiotic residues in raw commingled cow's milk. OBJECTIVE: The method performance was evaluated according to Commission Decision 2002/657/EC, Commission Implementing Regulation 2021/808, and Community Reference Laboratories Residues Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines. METHODS: The AnticFast Beta-Lactams Rapid Test Kit was evaluated for detection capability, selectivity, false-positive results, repeatability, robustness, suitability for various milk types and milk compositions, milks from various species, and test kit consistency and stability. Samples included milks spiked at concentrations bracketing the EU maximum residue limits (MRLs) for ß-lactams as well as bulk farm and tanker milks. RESULTS: The AnticFast Beta-Lactams Rapid Test Kit is specific for the detection of ß-lactams in milk and does not detect compounds from other antibiotic families. Interference was seen with clavulanic acid, a ß-lactamase inhibitor, which was expected. The test can detect all residues of ß-lactams (penicillins and cephalosporins) present on the EU-MRL list for milk at their respective MRL except for desfuroylceftiofur and cephalexin, which were above the MRL. No false positives were detected in the 602 (300 blank farm and 302 tanker load) samples tested. Robustness testing indicated that the detection in heat-treated milk types may be slightly hampered. For substances with a detection capability well below the MRL, this interference does not cause problems since detection at MRL remains guaranteed, but care should be taken for substances with a CCß at or near their MRL. Diminished sample flow was seen with reconstituted milk powder and blank ewes' milk, so sample flow should always be verified for these milk types. CONCLUSIONS: Results of this validation show that the AnticFast Beta-Lactams Rapid Test Kit is a reliable test for rapid screening of raw cows' milk for residues of ß-lactam antibiotics. HIGHLIGHTS: AnticFast Beta-Lactams Rapid Test Kit is an easy, realiable, robust and highly specific test for screening of raw cows' milk for residues of penicillins and cephalosporins.


Assuntos
Resíduos de Drogas , beta-Lactamas , Animais , Feminino , Ovinos , Bovinos , beta-Lactamas/análise , Penicilinas/análise , Cefalosporinas/análise , Leite/química , Resíduos de Drogas/análise , Antibacterianos/análise , Monobactamas/análise , Contaminação de Alimentos/análise
14.
Med Phys ; 50(5): 3127-3136, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36960718

RESUMO

BACKGROUND: Stereotactic radiotherapy (SRT) has been widely used for the treatment of brain metastases and early stage non-small-cell lung cancer (NSCLC). Excellent SRT plans are characterized by steep dose fall-off, making it critical to accurately and comprehensively predict and evaluate dose fall-off. PURPOSE: A novel dose fall-off index was proposed to ensure high-quality SRT planning. METHODS: The novel gradient index (NGI) had two different modes: NGIx V for three-dimensions and NGIx r for one-dimension. NGIx V and NGIx r were defined as the ratios of the decreased percentage dose (x%) to the corresponding isodose volume and equivalent sphere radii, respectively. A total of 243 SRT plans at our institution between April 2020 and March 2022 were enrolled, including 126 brain and 117 lung SRT plans. Measurement-based verifications were performed using SRS MapCHECK. Ten plan complexity indexes were calculated. Dosimetric parameters related to radiation injuries were also extracted, including the normal brain volume exposed to 12 Gy (V12 ) and 18 Gy (V18 ) during single-fraction SRT (SF-SRT) and multi-fraction SRT (MF-SRT), respectively, and the normal lung volume exposed to 12 Gy (V12 ). The performance of NGI and other common dose fall-off indexes, gradient index (GI), R50% and D2cm were evaluated using Spearman correlation analysis to explore their correlations with the PTV size, gamma passing rate (GPR), plan complexity indexes, and dosimetric parameters. RESULTS: There were statistically significant correlations between NGI and PTV size (r = -0.98, P < 0.01 for NGI50 V and r = -0.93, P < 0.01 for NGI50 r), which were the strongest correlations compared with GI (r = 0.11, P = 0.13), R50% (r = -0.08, P = 0.19) and D2cm (r = 0.84, P < 0.01). The fitted formulas of NGI50 V = 23.86V-1.00 and NGI50 r = 113.5r-1.05 were established. The GPRs of enrolled SRT plans were 98.6 ± 1.7%, 94.2 ± 4.7% and 97.1 ± 3.1% using the criteria of 3%/2 mm, 3%/1 mm, and 2%/2 mm, respectively. NGI50 V achieved the strongest correlations with various plan complexity indexes (|r| ranged from 0.67 to 0.91, P < 0.01). NGI50 V also showed the highest r values with V12 (r = -0.93, P < 0.01) and V18 (r = -0.96, P < 0.01) of the normal brain during SF-SRT and MF-SRT, respectively, and V12 (r = -0.86, P < 0.01) of the normal lung during lung SRT. CONCLUSIONS: Compared with GI, R50% and D2cm , the proposed dose fall-off index, NGI, had the strongest correlations with the PTV size, plan complexity and V12 /V18 of the normal tissues. These correlations established on NGI are more helpful and reliable for SRT planning, quality control, and reducing the risk of radiation injuries.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Lesões por Radiação , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radiocirurgia/métodos , Pulmão , Encéfalo , Radioterapia de Intensidade Modulada/métodos
15.
ACS Appl Mater Interfaces ; 15(38): 44631-44640, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37706663

RESUMO

In photothermal treatments (PTTs), normal tissues around cancerous tumors get injured by excessive heat, whereas damaged cancer cells are easily restored by stress-induced heat shock proteins (HSPs) at low temperatures. Therefore, to achieve a unique tumor microenvironment (TME), it is imperative to increase PTT efficiency and reduce normal tissue injury by adopting appropriate reactive oxygen species (ROS) and lipid peroxides (LPO) cross-linked with HSPs. In the present research, a potential strategy for mild photothermal treatments (mPTTs) was proposed by initiating localized catalytic chemical reactions in TME based on Pd nanozyme-modified hydrogenated TiO2 (H-TiO2@Pd). In vitro and in vivo evaluations demonstrated that H-TiO2@Pd had good peroxidase-like activities (POD), glutathione oxidase-like activities (GSHOx), and photodynamic properties and also satisfactory biocompatibility for 4T1 cells. Localized catalytic chemical reactions in H-TiO2@Pd significantly depleted GSH to downregulate the protein expression of GPX4 and promoted the accumulation of LPO and ROS, which consumed HSP70 or inhibited its function in 4T1 cells. Hence, the as-constructed low-temperature photothermal therapeutic platform based on Pd nanozyme-modified H-TiO2 can be a promising candidate to develop a safe and effective mPTT for cancer treatments.


Assuntos
Peróxidos Lipídicos , Terapia Fototérmica , Espécies Reativas de Oxigênio , Temperatura , Catálise
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 271: 120915, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35121472

RESUMO

Both HClO and pH are essential players in multiple biological processes, which thus need to be controlled properly. Dysregulated HClO or pH correlates with many diseases. To meet these challenges, we need to develop highly competent probes for monitoring them. Over the years, despite a rich history of the development of HClO or pH probes, those that can do both jobs are still deficient. Herein, we present a novel dual-functional chemosensor, CMHN, which exhibits a blue and red shift of its fluorescence emission upon reacting with HClO or OH-, respectively. CMHN was successfully harnessed in the imaging detection of HClO or OH- in aqueous solutions, live cells, and zebrafish. Results indicated CMHN can detect HClO with high sensitivity (LOD -132 nM), a quick response time (<70 s), and high selectivity over dozens of interfering species through a colorimetric and ratiometric response. Besides, CMHN can probe pH changes sensitively and reversibly. Its working mechanism was verified by DFT calculations. These superior features make CMHN excel among the HClO or pH probes reported so far. Taken together, CMHN replenishes the deficiency in currently developed HClO or pH probes and paves the way for developing multifunctional HClO or pH probes in the future.


Assuntos
Ácido Hipocloroso , Peixe-Zebra , Animais , Colorimetria , Corantes Fluorescentes , Concentração de Íons de Hidrogênio
17.
Colloids Surf B Biointerfaces ; 218: 112755, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35973237

RESUMO

Strontium carbonate (SrC) bioceramics are proposed as potential biomaterials to efficaciously repair the bone defects. However, the development of SrC bioceramics is restricted by their intrinsic low mechanical strength. In this study, SrC-based composite bioceramics (SrC-SrP) were fabricated by incorporating strontium-containing phosphate glass (SrP). The results indicated that aside from the main crystalline phase SrC, new compounds were generated in the SrC-SrP bioceramics. Incorporating 10 wt% SrP promoted densification, thus dramatically improving compressive strength of SrC-SrP bioceramics. The SrC-SrP bioceramics facilitated apatite precipitation on their surface, and sustainedly released strontium, phosphorus and sodium ions. Compared with the well-known ß-tricalcium phosphate bioceramics, the SrC-SrP bioceramics with certain amounts of SrP enhanced proliferation, alkaline phosphatase activity and osteogenesis-related gene expressions of mouse bone mesenchymal stem cells. The SrC-SrP bioceramics with appropriate constituent can serve as novel bone regenerative biomaterials.


Assuntos
Fosfatase Alcalina , Materiais Biocompatíveis , Fosfatase Alcalina/metabolismo , Animais , Apatitas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Carbonatos , Cerâmica/química , Cerâmica/farmacologia , Camundongos , Osteogênese/genética , Fosfatos , Fósforo , Sódio , Estrôncio/química , Estrôncio/farmacologia
18.
ACS Appl Mater Interfaces ; 14(48): 53475-53490, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36413755

RESUMO

Hydrogen sulfide releasing agents (or H2S donors) have been recognized gasotransmitters with potent cytoprotective and anticancer properties. However, the clinical application of H2S donors has been hampered by their fast H2S-release, instability, and lack of tumor targeting, despite the unclear molecular mechanism of H2S action. Here we rationally designed an amphiphilic pentapeptide (RGDFF) to coassemble with the de novo designed thiol-activated H2S donors (CL2/3) into nanocarriers for targeted therapy of non-small-cell lung cancer, which has been proved as a one-stone-three-birds strategy. The coassembly approach simply solved the solubility issue of CL2/3 by the introduction of electron-donating groups (phenyl rings) to slow down the H2S release while dramatically improving their biocompatible interface, circulation time, slow release of H2S, and tumor targeting. Experimental results confirmed that as-prepared coassembled nanocarriers can significantly induce the intrinsic apoptotic, effectively arrest cell cycle at the G2/M phase, inhibit H2S-producing enzymes, and lead to mitochondrial dysfunction by increasing intracellular ROS production in H1299 cells. The mouse tumorigenesis experiments further confirmed the in vivo anticancer effects of the coassembled nanocarriers, and such treatment made tumors more sensitive to radiotherapy then improved the prognosis of tumor-bearing mice, which holds great promise for developing a new combined approach for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Sulfeto de Hidrogênio , Neoplasias Pulmonares , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Compostos de Sulfidrila
19.
Radiat Oncol ; 16(1): 134, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289863

RESUMO

BACKGROUND: Both patient-specific dose recalculation and γ passing rate analysis are important for the quality assurance (QA) of intensity modulated radiotherapy (IMRT) plans. The aim of this study was to analyse the correlation between the γ passing rates and the volumes of air cavities (Vair) and bony structures (Vbone) in target volume of head and neck cancer. METHODS: Twenty nasopharyngeal carcinoma and twenty nasal natural killer T-cell lymphoma patients were enrolled in this study. Nine-field sliding window IMRT plans were produced and the dose distributions were calculated by anisotropic analytical algorithm (AAA), Acuros XB algorithm (AXB) and SciMoCa based on the Monte Carlo (MC) technique. The dose distributions and γ passing rates of the targets, organs at risk, air cavities and bony structures were compared among the different algorithms. RESULTS: The γ values obtained with AAA and AXB were 95.6 ± 1.9% and 96.2 ± 1.7%, respectively, with 3%/2 mm criteria (p > 0.05). There were significant differences (p < 0.05) in the γ values between AAA and AXB in the air cavities (86.6 ± 9.4% vs. 98.0 ± 1.7%) and bony structures (82.7 ± 13.5% vs. 99.0 ± 1.7%). Using AAA, the γ values were proportional to the natural logarithm of Vair (R2 = 0.674) and inversely proportional to the natural logarithm of Vbone (R2 = 0.816). When the Vair in the targets was smaller than approximately 80 cc or the Vbone in the targets was larger than approximately 6 cc, the γ values of AAA were below 95%. Using AXB, no significant relationship was found between the γ values and Vair or Vbone. CONCLUSION: In clinical head and neck IMRT QA, greater attention should be paid to the effect of Vair and Vbone in the targets on the γ passing rates when using different dose calculation algorithms.


Assuntos
Osso e Ossos/patologia , Neoplasias de Cabeça e Pescoço/patologia , Linfoma Extranodal de Células T-NK/patologia , Carcinoma Nasofaríngeo/patologia , Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Osso e Ossos/efeitos da radiação , Raios gama , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Linfoma Extranodal de Células T-NK/radioterapia , Método de Monte Carlo , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Prognóstico , Dosagem Radioterapêutica
20.
J Oncol ; 2021: 6690275, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859690

RESUMO

In clinical practice, tegafur, gimeracil, and oteracil potassium (S-1) therapy is commonly administered to treat nasopharyngeal carcinoma (NPC). However, its efficacy and safety remain controversial in both randomized controlled trials (RCTs) and non-RCTs. We aimed to evaluate the efficacy and safety of S-1 treatment for NPC. We searched PubMed, Ovid, EMBASE, the Cochrane Library, China National Knowledge Infrastructure, Wanfang Database, and VIP databases for RCTs of chemotherapy with or without S-1 for NPC, from 2001 to 2020. A meta-analysis was performed using RevMan5.3 and Stata15. Randomized controlled trials published in journals were included irrespective of blinding and language used. Patients were diagnosed with NPC through a clinicopathological examination; patients of all cancer stages and ages were included. Overall, 25 trials and 1858 patients were included. There were significant differences in the complete remission (OR = 2.42, 95% CI (1.88-3.10), P < 0.05) and overall response rate (OR = 2.68, 95% CI (2.08-3.45), P < 0.05) between the S-1 and non-S-1 groups. However, there was no significant difference in partial remission (OR = 1.10, 95% CI (0.87-1.39), P=0.42) and seven adverse reactions (leukopenia, thrombocytopenia, nausea and vomiting, diarrhea, dermatitis, oral mucositis, and anemia) between the S-1 and non-S-1 groups. Additionally, statistical analyses with six subgroups were performed. S-1 was found to be a satisfactory chemotherapeutic agent combined with radiotherapy, intravenous chemotherapy, or chemoradiotherapy for NPC. As an oral medicine, the adverse reactions of S-1, especially gastrointestinal reactions, can be tolerated by patients, thereby optimizing their quality of life. S-1 may be a better choice for the treatment of NPC. This trial is registered with CRD42019122041.

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