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1.
J Nanosci Nanotechnol ; 19(4): 2166-2173, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486961

RESUMO

Osteoclasts are multinucleated terminal cells that originate from a hematopoietic monocyte/macrophage lineage. Excessive osteoclast formation in vivo can lead to bone metabolic diseases such as postmenopausal osteoporosis, multiple myeloma, rheumatoid arthritis, and lytic bone metastases of cancer cells. Au nanoparticles (AuNPs) are inorganic nanoparticles with outstanding biocompatibility. We assessed their effect on osteoclastogenesis and found that pre-osteoclast fusion induced by receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colonystimulating factor (M-CSF) was suppressed by AuNPs. Cell migration and actin ring formation were also significantly inhibited. Finally, AuNPs reduced osteoclast bone absorption function. Interestingly, we observed altered fusogenic gene expression in treated pre-osteoclasts. Our results suggest that AuNPs have potential as a therapeutic agent for osteoclast-related bone metabolism diseases.


Assuntos
Nanopartículas Metálicas , Osteoclastos , Diferenciação Celular , Ouro/farmacologia , Osteogênese/genética
2.
Part Fibre Toxicol ; 15(1): 5, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343276

RESUMO

BACKGROUND: Nanoparticles (NPs) administered orally will meet the gut microbiota, but their impacts on microbiota homeostasis and the consequent physiological relevance remain largely unknown. Here, we describe the modulatory effects and the consequent pharmacological outputs of two orally administered fullerenols NPs (Fol1 C60(OH)7(O)8 and Fol113 C60(OH)11(O)6) on gut microbiota. RESULTS: Administration of Fol1 and Fol113 NPs for 4 weeks largely shifted the overall structure of gut microbiota in mice. The bacteria belonging to putative short-chain fatty acids (SCFAs)-producing genera were markedly increased by both NPs, especially Fol1. Dynamic analysis showed that major SCFAs-producers and key butyrate-producing gene were significantly enriched after treatment for 7-28 days. The fecal contents of SCFAs were consequently increased, which was accompanied by significant decreases of triglycerides and total cholesterol levels in the blood and liver, with Fol1 superior to Fol113. Under cultivation in vitro, fullerenols NPs can be degraded by gut flora and exhibited a similar capacity of inulin to promote SCFA-producing genera. The differential effects of Fol1 and Fol113 NPs on the microbiome may be attributable to their subtly varied surface structures. CONCLUSIONS: The two fullerenol NPs remarkably modulate the gut microbiota and selectively enrich SCFA-producing bacteria, which may be an important reason for their anti-hyperlipidemic effect in mice.


Assuntos
Fulerenos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Hipolipemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Nanopartículas , Animais , Ácidos Graxos Voláteis/biossíntese , Fezes/microbiologia , Fulerenos/química , Fulerenos/farmacocinética , Microbioma Gastrointestinal/genética , Homeostase/efeitos dos fármacos , Hipolipemiantes/química , Hipolipemiantes/farmacocinética , Masculino , Camundongos Endogâmicos C57BL , Filogenia , RNA Ribossômico 16S/genética , Propriedades de Superfície , Distribuição Tecidual
3.
Int J Mol Sci ; 19(9)2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30227604

RESUMO

Endocytosis is an important pathway to regulate the metabolism of low-density lipoprotein (LDL) in cells. At the same time, engineering nanoparticles (ENPs) enter the cell through endocytosis in biomedical applications. Therefore, a crucial question is whether the nanoparticles involved in endocytosis could impact the natural metabolism of LDL in cells. In this study, we fabricated a series of gold nanoparticles (AuNPs) (13.00 ± 0.69 nm) with varied surface charge densities. The internalized AuNPs with high-surface negative-charge densities (HSNCD) significantly reduced LDL uptake in HepG-2, HeLa, and SMMC-7721 cells compared with those cells in control group. Notably, the significant reduction of LDL uptake in cells correlates with the reduction of LDL receptors (LDL-R) on the cell surface, but there is no change in protein and mRNA of LDL-Rs. The cyclic utilization of LDL-R in cells is a crucial pathway to maintain the homoeostasis of LDL uptake. The release of LDL-Rs from LDL/LDL-R complexes in endosomes depended on reduction of the pH in the lumen. AuNPs with HSNCD hampered vacuolar-type H⁺-ATPase V1 (ATPaseV1) and ATPaseV0 binding on the endosome membrane, blocking protons to enter the endosome by the pump. Hence, fewer freed LDL-Rs were transported into recycling endosomes (REs) to be returned to cell surface for reuse, reducing the LDL uptake of cells by receptor-mediated endocytosis. The restrained LDL-Rs in the LDL/LDL-R complex were degraded in lysosomes.


Assuntos
Ouro/metabolismo , Lipoproteínas LDL/metabolismo , Nanopartículas/metabolismo , Transporte Biológico , Endocitose , Endossomos/metabolismo , Ouro/química , Células Hep G2 , Humanos , Lisossomos/metabolismo , Nanopartículas/química , Nanopartículas/ultraestrutura , Receptores de LDL/metabolismo , Eletricidade Estática , Propriedades de Superfície
4.
Int J Mol Sci ; 19(3)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29494500

RESUMO

The excellent biocompatibility and biological effects of fullerenol and its derivatives make their biomedical application promising. The potential effects of fullerenol in mammals have been extensively studied, but little is known about its effects on female reproduction. Using canonical oocyte-granulosa cell complexes (OGCs) in vitro maturation culture model, we investigated the effect of fullerenol on the first oocyte meiotic resumption. In the surrounding granulosa cells, fullerenol nanoparticles occluded the extracellular domain of the epidermal growth factor receptor (EGFR) to reduce EGFR-ligand binding and subsequent extracellular signal-regulated kinase 1 and 2 (ERK1/2) activation, which involved the regulation of connexin 43 (CX43) expression and internalization. Downregulation of CX43 expression and the retraction of transzonal projections (TZPs) interrupted the gap junction channel and TZPs based mass transportation. This effect decreased cyclic adenosine monophosphate (cAMP) levels in the oocyte and thereby accelerated rat oocyte meiosis resumption. Moreover, perinuclear distribution of CX43 and EGFR was observed in granulosa cells, which could further exacerbate the effects. Fullerenol nanoparticles interfered with the strict process of oocyte meiosis resumption, which likely reduced the oocyte quality.


Assuntos
Fulerenos/farmacologia , Meiose/efeitos dos fármacos , Nanopartículas , Oócitos/metabolismo , Animais , Conexina 43/genética , Conexina 43/metabolismo , AMP Cíclico , Receptores ErbB/metabolismo , Feminino , Fulerenos/química , Junções Comunicantes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ligação Proteica , Transporte Proteico/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos
5.
Int J Mol Sci ; 16(12): 28334-46, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26633364

RESUMO

Carbon ion radiation is a promising treatment for brain cancer; however, the immune system involved long-term systemic effects evoke a concern of complementary and alternative therapies in clinical treatment. To clarify radiotherapy caused fundamental changes in peripheral immune system, examinations were performed based on established models in vitro and in vivo. We found that brain-localized carbon ion radiation of neural cells induced complex changes in the peripheral blood, thymus, and spleen at one, two, and three months after its application. Atrophy, apoptosis, and abnormal T-cell distributions were observed in rats receiving a single high dose of radiation. Radiation downregulated the expression of proteins involved in T-cell development at the transcriptional level and increased the proportion of CD3⁺CD4(-)CD8⁺ T-cells in the thymus and the proportion of CD3⁺CD4⁺CD8(-) T-cells in the spleen. These data show that brain irradiation severely affects the peripheral immune system, even at relatively long times after irradiation. In addition, they provide valuable information that will implement the design of biological-based strategies that will aid brain cancer patients suffering from the long-term side effects of radiation.


Assuntos
Carbono , Íons , Sistema Nervoso/imunologia , Sistema Nervoso/efeitos da radiação , Lesões Experimentais por Radiação/imunologia , Radiação Ionizante , Animais , Apoptose/imunologia , Apoptose/efeitos da radiação , Biomarcadores , Encéfalo/imunologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/efeitos da radiação , Linhagem Celular , Modelos Animais de Doenças , Humanos , Terapia de Imunossupressão , Ativação Linfocitária/imunologia , Ativação Linfocitária/efeitos da radiação , Masculino , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Ratos , Baço/imunologia , Baço/metabolismo , Baço/patologia , Baço/efeitos da radiação , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Linfócitos T/efeitos da radiação , Timo/imunologia , Timo/patologia , Timo/efeitos da radiação
6.
Mol Biol Rep ; 41(9): 5729-34, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24928088

RESUMO

Reactive oxygen species (ROS) are produced due to oxidative stress which has wide range of affiliation with different diseases including cancer, heart failure, diabetes and neurodegenerative diseases like Alzheimer's disease, Parkinson's disease, ischemic and hemorrhagic diseases. This study shows the involvement of BNIP3 in the amplification of metabolic pathways related to cellular quality control and cellular self defence mechanism in the form of autophagy. We used conventional methods to induce autophagy by treating the cells with H2O2. MTT assay was performed to observe the cellular viability in stressed condition. MDC staining was carried out for detection of autophagosomes formation which confirmed the autophagy. Furthermore, expression of BNIP3 was validated by western blot analysis with LC3 antibody. From these results it is clear that BNIP3 plays a key role in defence mechanism by removing the misfolded proteins through autophagy. These results enhance the practical application of BNIP3 in neuroblastoma cells and are helpful in reducing the chances of neurodegenerative diseases. Although, the exact mode of action is still unknown but these findings unveil a molecular mechanism for the role of autophagy in cell death and provide insight into complex relationship between ROS and non-apoptotic programmed cell death.


Assuntos
Autofagia/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Neuroblastoma/patologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas/metabolismo , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Peróxido de Hidrogênio/efeitos adversos , Proteínas de Membrana/genética , Neuroblastoma/metabolismo , Plasmídeos/genética , Proteínas Proto-Oncogênicas/genética , Espécies Reativas de Oxigênio/metabolismo
8.
Radiat Oncol ; 19(1): 77, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909242

RESUMO

BACKGROUND: Volumetric modulated arc therapy (VMAT) is a novel form of IMRT, which can deliver more accurate dose distribution and shorten treatment time. Compared to MRI-guided adaptive brachytherapy, which is recommended as gold standard imaging for cervical cancer contours, CT-guided adaptive brachytherapy (CTGAB) is more available, more widespread, and more affordable in many centers. This study aims to retrospectively analyze the efficacy and the safety of VMAT combined with CTGAB for patients with locally advanced cervical cancer. METHODS AND MATERIALS: This study retrospectively analyzed 102 patients with locally advanced cervical cancer who underwent VMAT and CTGAB. Clinical outcomes including local control (LC), overall survival (OS) and progression-free survival (PFS), tumor response to treatment evaluated by the Response Evaluation Criteria in Solid Tumors (RECIST) (version 1.1), and toxicities including gastrointestinal toxicity, urinary toxicity and hematologic toxicity evaluated by the Common Terminology Criteria for Adverse Events (CTCAE) (version 5.0) were analyzed. The Kaplan-Meier method was used to calculate LC, OS, and PFS. RESULTS: Median follow-up time was 19 months. Complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) occurred in 68 (66.7%), 24 (23.5%), 4 (3.92%), and 6 (5.88%), respectively. The 2-year and 3-year OS were 89.6% and 83%, respectively. The 2-year and 3-year PFS were 84.2% and 74.3%, respectively. The 2-year and 3-year LC were 90.1% and 79.3%, respectively. The average cumulative D2cm3 in the rectum, the bladder, the colon, and the small intestine were 78.07 (SD: 0.46) Gy, 93.20 (SD: 0.63) Gy, 63.55 (SD: 1.03) Gy and 61.07 (SD: 0.75) Gy, respectively. The average cumulative D90% of the high-risk clinical target volume (HR-CTV) was 92.26 (SD: 0.35) Gy. Grade ≥ 3 gastrointestinal and urinary toxicities occurred in 4.9% and 0.98%, respectively. 1.96% of patients were observed grade ≥ 4 gastrointestinal toxicities and none of the patients observed grade ≥ 4 urinary toxicities. CONCLUSION: VMAT combined with CTGAB for locally advanced cervical cancer was an effective and safe treatment method, which showed satisfactory LC, OS, PFS, and acceptable toxicities.


Assuntos
Braquiterapia , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Tomografia Computadorizada por Raios X , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/mortalidade , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Braquiterapia/métodos , Braquiterapia/efeitos adversos , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Idoso , Radioterapia Guiada por Imagem/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Idoso de 80 Anos ou mais , Taxa de Sobrevida
9.
Phys Med ; 122: 103377, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838467

RESUMO

PURPOSE: To investigate the clinical impact of plan complexity on the local recurrence-free survival (LRFS) of non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiation therapy (SBRT). METHODS: Data from 123 treatment plans for 113 NSCLC patients were analyzed. Plan-averaged beam modulation (PM), plan beam irregularity (PI), monitor unit/Gy (MU/Gy) and spherical disproportion (SD) were calculated. The γ passing rates (GPR) were measured using ArcCHECK 3D phantom with 2 %/2mm criteria. High complexity (HC) and low complexity (LC) groups were statistically stratified based on the aforementioned metrics, using cutoffs determined by their significance in correlation with survival time, as calculated using the R-3.6.1 packages. Kaplan-Meier analysis, Cox regression, and Random Survival Forest (RSF) models were employed for the analysis of local recurrence-free survival (LRFS). Propensity-score-matched pairs were generated to minimize bias in the analysis. RESULTS: The median follow-up time for all patients was 25.5 months (interquartile range 13.4-41.2). The prognostic capacity of PM was suggested using RSF, based on Variable Importance and Minimal Depth methods. The 1-, 2-, and 3-year LRFS rates in the HC group were significantly lower than those in the LC group (p = 0.023), when plan complexity was defined by PM. However, no significant difference was observed between the HC and LC groups when defined by other metrics (p > 0.05). All γ passing rates exceeded 90.5 %. CONCLUSIONS: This study revealed a significant association between higher PM and worse LRFS in NSCLC patients treated with SBRT. This finding offers additional clinical evidence supporting the potential optimization of pre-treatment quality assurance protocols.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/radioterapia , Masculino , Feminino , Planejamento da Radioterapia Assistida por Computador/métodos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Recidiva Local de Neoplasia , Intervalo Livre de Doença , Estudos Retrospectivos
10.
ACS Appl Mater Interfaces ; 16(3): 3232-3242, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38221726

RESUMO

Accurate prediction of the relative biological effectiveness (RBE) of boron neutron capture therapy (BNCT) is challenging. The therapy is different from other radiotherapy; the dynamic distribution of boron-containing compounds in tumor cells affects the therapeutic outcome considerably and hampers accurate measurement of the neutron-absorbed dose. Herein, we used boron-containing metal-organic framework nanoparticles (BMOFs) with high boron content to target U87-MG cells and maintain the concentration of the 10B isotope in cells. The content of boron in the cells could maintain 90% (60 ppm) within 20 min compared with that at the beginning; therefore, the accurate RBE of BNCT can be acquired. The effects of BNCT upon cells after neutron irradiation were observed, and the neutron-absorbed dose was obtained by Monte Carlo simulations. The RBE of BMOFs was 6.78, which was 4.1-fold higher than that of a small-molecule boron-containing agent (boric acid). The energy spectrum of various particles was analyzed by Monte Carlo simulations, and the RBE was verified theoretically. Our results suggested that the use of nanoparticle-based boron carriers in BNCT may have many advantages and that maintaining a stable boron distribution within cells may significantly improve the efficiency of BNCT.


Assuntos
Terapia por Captura de Nêutron de Boro , Boro , Terapia por Captura de Nêutron de Boro/métodos , Eficiência Biológica Relativa , Nêutrons
11.
Int J Mol Sci ; 15(1): 1-14, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24451124

RESUMO

The effect of chemotherapy drug Mitomycin C (MMC) in combination with recombinant adeno-associated virus II (rAAV2) in cancer therapy was investigated, and the mechanism of MMC affecting rAAV2's bioactivity was also studied. The combination effect was evaluated by the level of GFP and TNF expression in a human glioma cell line, and the mechanism of MMC effects on rAAV mediated gene expression was investigated by AAV transduction related signal molecules. C57 and BALB/c nude mice were injected with rAAV-EGFP or rAAV-TNF alone, or mixed with MMC, to evaluate the effect of MMC on AAV-mediated gene expression and tumor suppression. MMC was shown to improve the infection activity of rAAV2 both in vitro and in vivo. Enhancement was found to be independent of initial rAAV2 receptor binding stage or subsequent second-strand synthesis of target DNA, but was related to cell cycle retardation followed by blocked genome degradation. In vivo injection of MMC combined with rAAV2 into the tumors of the animals resulted in significant suppression of tumor growth. It was thus demonstrated for the first time that MMC could enhance the expression level of the target gene mediated by rAAV2. The combination of rAAV2 and MMC may be a promising strategy in cancer therapy.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Dependovirus/genética , Mitomicina/uso terapêutico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Genética , Vetores Genéticos/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Mitomicina/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transplante Heterólogo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
Front Cell Neurosci ; 17: 1252958, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107411

RESUMO

Background and objective: Heavy ion radiation is one of the major hazards astronauts face during space expeditions, adversely affecting the central nervous system. Radiation causes severe damage to sensitive brain regions, especially the striatum, resulting in cognitive impairment and other physiological issues in astronauts. However, the intensity of brain damage and associated underlying molecular pathological mechanisms mediated by heavy ion radiation are still unknown. The present study is aimed to identify the damaging effect of heavy ion radiation on the striatum and associated underlying pathological mechanisms. Materials and methods: Two parallel cohorts of rats were exposed to radiation in multiple doses and times. Cohort I was exposed to 15 Gy of 12C6+ ions radiation, whereas cohort II was exposed to 3.4 Gy and 8 Gy with 56Fe26+ ions irradiation. Physiological and behavioural tests were performed, followed by 18F-FDG-PET scans, transcriptomics analysis of the striatum, and in-vitro studies to verify the interconnection between immune cells and neurons. Results: Both cohorts revealed more persistent striatum dysfunction than other brain regions under heavy ion radiation at multiple doses and time, exposed by physiological, behavioural, and 18F-FDG-PET scans. Transcriptomic analysis revealed that striatum dysfunction is linked with an abnormal immune system. In vitro studies demonstrated that radiation mediated diversified effects on different immune cells and sustained monocyte viability but inhibited its differentiation and migration, leading to chronic neuroinflammation in the striatum and might affect other associated brain regions. Conclusion: Our findings suggest that striatum dysfunction under heavy ion radiation activates abnormal immune systems, leading to chronic neuroinflammation and neuronal injury.

13.
Med Phys ; 49(11): 7316-7326, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35833330

RESUMO

PURPOSE: Automatic segmentation of colon, small intestine, and duodenum is a challenging task because of the great variability in the scale of the target organs. Multi-scale features are the key to alleviating this problem. Previous works focused on extracting discriminative multi-scale features through a hierarchical structure. Instead, the purpose of this work is to exploit these powerful multi-scale features more efficiently. METHODS: A Scale Attention Module (SAM) was proposed to recalibrate multi-scale features by explicitly modeling their importance score adaptively. The SAM was introduced into the segmentation model to construct the Scale Attention Network (SANet). The multi-scale features extracted from the encoder were first re-extracted to obtain more specific multi-scale features. Then the SAM was applied to recalibrate the features. Specifically, for the feature of each scale, a summation of Global Average Pooling and Global Max Pooling was used to create scale-wise feature representations. According to the representations, a lightweight network was used to generate the importance score of each scale. The features were recalibrated based on the scores, and a simple pixel-by-pixel summation was used to fuse the multi-scale features. The fused multi-scale feature was fed into a segmentation head to complete the task. RESULTS: The models were evaluated using fivefold cross-validation on 70 upper abdominal computed tomography scans of patients in a volume manner. The results showed that SANet could effectively alleviate the scale-variability problem and achieve better performance compared with UNet, Attention UNet, UNet++, Deeplabv3p, and CascadedUNet. The Dice similarity coefficients (DSCs) of colon, small intestine, and duodenum were (84.06 ± 3.66)%, (76.79 ± 5.12)%, and (61.68 ± 4.32)%, respectively. The HD95 were (7.51 ± 2.45) mm, (11.08 ± 2.45) mm, and (12.21 ± 1.95) mm, respectively. The values of relative volume difference were (3.4 ± 0.8)%, (11.6 ± 11.81)%, and (6.2 ± 3.71)%, respectively. The values of center-of-mass distance were 7.85 ± 2.82, 9.89 ± 2.70, and 9.94 ± 1.58, respectively. Compared with other attention modules and multi-scale feature exploitation approaches, SAM could obtain a 0.83-2.71 points improvement in terms of DSC with a comparable or even less number of parameters. The extensive experiments confirmed the effectiveness of SAM. CONCLUSIONS: The SANet can efficiently exploit multi-scale features to alleviate the scale-variability problem and improve the segmentation performance on colon, small intestine, and duodenum of the upper abdomen.


Assuntos
Duodeno , Intestino Delgado , Humanos , Intestino Delgado/diagnóstico por imagem , Duodeno/diagnóstico por imagem , Colo , Projetos de Pesquisa , Tomografia Computadorizada por Raios X
14.
Front Oncol ; 11: 702171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367986

RESUMO

BACKGROUND: To improve the quality of plan for the radiation treatment of advanced left breast cancer by introducing the auxiliary structures (ASs) which are used to spare the regions with no intact delineated structures adjacent to the target volume. METHODS: CT data from 20 patients with left-sided advanced breast cancer were selected. An AS designated as A1 was created to spare the regions of the aorta, pulmonary artery, superior vena ava, and contralateral tissue of the upper chest and neck, and another, designated as A2, was created in the regions of the cardia and fundus of the stomach, left liver lobe, and splenic flexure of the colon. IMRT and VMAT plans were created for cases with and without the use of the AS dose constraints in plan optimization. Dosimetric parameters of the target and organs at risk (OARs) were compared between the separated groups. RESULTS: With the use of AS dose constraints, both the IMRT and VMAT plans were clinically acceptable and deliverable, even showing a slight improvement in dose distribution of both the target and OARs compared with the AS-unused plans. The ASs significantly realized the dose sparing for the regions and brought a better conformity index (p < 0.05) and homogeneity index (p < 0.05) in VMAT plans. In addition, the volume receiving at least 20 Gy (V20) for the heart (p < 0.05), V40 for the left lung (p < 0.05), and V40 for the axillary-lateral thoracic vessel juncture region (p < 0.05) were all lower in VMAT plans. CONCLUSION: The use of the defined AS dose constraints in plan optimization was effective in sparing the indicated regions, improving the target dose distribution, and sparing OARs for advanced left breast cancer radiotherapy, especially those that utilize VMAT plans.

15.
J Radiat Res ; 62(1): 94-103, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33029634

RESUMO

For deep learning networks used to segment organs at risk (OARs) in head and neck (H&N) cancers, the class-imbalance problem between small volume OARs and whole computed tomography (CT) images results in delineation with serious false-positives on irrelevant slices and unnecessary time-consuming calculations. To alleviate this problem, a slice classification model-facilitated 3D encoder-decoder network was developed and validated. In the developed two-step segmentation model, a slice classification model was firstly utilized to classify CT slices into six categories in the craniocaudal direction. Then the target categories for different OARs were pushed to the different 3D encoder-decoder segmentation networks, respectively. All the patients were divided into training (n = 120), validation (n = 30) and testing (n = 20) datasets. The average accuracy of the slice classification model was 95.99%. The Dice similarity coefficient and 95% Hausdorff distance, respectively, for each OAR were as follows: right eye (0.88 ± 0.03 and 1.57 ± 0.92 mm), left eye (0.89 ± 0.03 and 1.35 ± 0.43 mm), right optic nerve (0.72 ± 0.09 and 1.79 ± 1.01 mm), left optic nerve (0.73 ± 0.09 and 1.60 ± 0.71 mm), brainstem (0.87 ± 0.04 and 2.28 ± 0.99 mm), right temporal lobe (0.81 ± 0.12 and 3.28 ± 2.27 mm), left temporal lobe (0.82 ± 0.09 and 3.73 ± 2.08 mm), right temporomandibular joint (0.70 ± 0.13 and 1.79 ± 0.79 mm), left temporomandibular joint (0.70 ± 0.16 and 1.98 ± 1.48 mm), mandible (0.89 ± 0.02 and 1.66 ± 0.51 mm), right parotid (0.77 ± 0.07 and 7.30 ± 4.19 mm) and left parotid (0.71 ± 0.12 and 8.41 ± 4.84 mm). The total segmentation time was 40.13 s. The 3D encoder-decoder network facilitated by the slice classification model demonstrated superior performance in accuracy and efficiency in segmenting OARs in H&N CT images. This may significantly reduce the workload for radiation oncologists.


Assuntos
Algoritmos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento Tridimensional , Órgãos em Risco/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
16.
Brachytherapy ; 19(3): 380-388, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32249183

RESUMO

OBJECTIVES: To evaluate the dosimetry, efficacy, and safety of radioactive 125I seed implantation (RISI) assisted by three-dimensional printing noncoplanar template (3D-PNCT) and CT for recurrent retroperitoneal lymphatic metastasis (RRLM) after previous external beam radiotherapy. METHODS AND MATERIALS: From June 2016 to August 2018, 32 patients with RRLM successfully underwent 3D-PNCT-assisted and CT-guided RISI. The dosimetry, pain relief rate, performance improvement rate, overall response rate, disease control rate, local control time (LCT), overall survival (OS), and safety profiles were evaluated. RESULTS: Dosimetric results showed that the D90, D100, V100, V150, V200, and homogeneity index were consistent in preoperation and postoperation (p > 0.05), except for the external index and conformal index (p = 0.048, p = 0.034). After RISI, 81.3% of the patients achieved pain relief, and 71.9% achieved an improvement of performance. The overall response rate and disease control rate were 85.3% and 94.1%, respectively. The LCT rates reached 66.2% and 43.2% in 1 year and two years, respectively, with a median LCT of 15.8 months. The OS rates were 74.1% and 28.1% in 1 year and two year, respectively, with a median OS reaching 17.6 months. Univariate analysis showed that when D90 > 130 Gy or D100 > 63 Gy or tumor size ≤49.8 cm3, LCT was extended significantly, but not for OS. Except for two patients developing Grade 1 retroperitoneal hematomas, no other severe adverse events were observed. CONCLUSIONS: 3D-PNCT and CT guidance provide excellent accuracy for RISI, which can be an effective and safe alternative for RRLM after external beam radiotherapy. Radiation dose and tumor size seem to significantly influence the local control.


Assuntos
Braquiterapia/instrumentação , Hematoma/etiologia , Metástase Linfática/radioterapia , Recidiva Local de Neoplasia/radioterapia , Espaço Retroperitoneal , Adulto , Idoso , Braquiterapia/efeitos adversos , Dor do Câncer/radioterapia , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Linfonodos/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Impressão Tridimensional , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Retratamento , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
17.
Brachytherapy ; 19(1): 81-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31653566

RESUMO

OBJECTIVES: The objective of this study was to evaluate the efficacy and safety of CT-guided radioactive 125I seed implantation as a salvage treatment for locally recurrent head and neck soft tissue sarcoma (HNSTS) after surgery and external beam radiotherapy. METHODS AND MATERIALS: From December 2006 to February 2018, 25 patients with locally recurrent HNSTS after surgery and external beam radiotherapy were enrolled. All the patients successfully underwent CT-guided 125I seed implantation. The primary end points included the objective response rate (ORR) and local progression-free survival (LPFS). The secondary end points were survival (OS) and safety profiles. RESULTS: After 125I seed implantation, the ORR was 76.0%. The 1-, 3-, and 5-year LPFS rates were 65.6%, 34.4%, and 22.9%, respectively, with the median LPFS of 16.0 months. The 1-, 3-, and 5-year OS rates were 70.8%, 46.6%, and 34.0%, respectively, with the median OS of 28.0 months. Furthermore, univariate analyses showed that the recurrent T stage and histological grade were prognostic factors of LPFS, whereas only the histological grade was a predictor of OS. The major adverse events were skin/mucosal toxicities, which were generally of lower grade (≤Grade 2) and were well tolerated. CONCLUSIONS: Radioactive 125I seed implantation could be an effective and safe alternative treatment for locally recurrent HNSTS after failure of surgery and radiotherapy. Recurrent T stage and histological grade were the main factors influencing the efficacy.


Assuntos
Braquiterapia/métodos , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Terapia de Salvação/métodos , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/radioterapia , Adulto , Braquiterapia/efeitos adversos , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Intervalo Livre de Progressão , Radioterapia Adjuvante , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia Guiada por Imagem/métodos , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Adulto Jovem
18.
Se Pu ; 37(4): 343-347, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-30977335

RESUMO

Extracellular vesicles (EVs) are hemispherical vesicles that have a lipid bilayer. Studies have shown that EVs have important biological functions. The amount, types, and compositional changes of proteins, lipids and ribonucleic acids are closely related to diseases. The separation and capture of EVs from the complicated body fluid samples is a prerequisite for medical research and liquid biopsy based on EVs. However, presently the majority of EVs separation and capture still use the traditional separation methods with low purity and low efficiency. Therefore, efficient and highly selective EVs separation method is in urgent need. To meet this challenge, advanced microfluidic chip technology, which has the advantages of miniaturization, integration, and automation, can be utilized. The development of EV separation technology combined with microfluidic chips has become the focus of research. This paper summarizes the latest research progress in this area.


Assuntos
Vesículas Extracelulares , Microfluídica/tendências
19.
Nanoscale ; 10(4): 1750-1758, 2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29308471

RESUMO

Understanding what modulates the cell stiffness is important given its potential application as a diagnostic and medical target. Here, we investigated why and how mono-fullerenols affect the cell stiffness. We confirmed the fullerenol-modulation of cell stiffness using atomic force microscopy (AFM) with sphere tips and ascertained that the particles reduce the cell polarity. The structures of b-actin and f-actin were evaluated by inverted fluorescence microscopy, synchrotron radiation small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and AFM. Statistical and quantitative analyses of the SAXS data of fullerenol-treated b-actin and f-actin reveal a transformation from large-size to small-size b-actin and simultaneously to f-actin. The slight increase in f-actin diameter in the treated group suggests that fullerenols attach to the actin surface. We verified the attachment using AFM and high-resolution probes. Collectively, our results suggest that fullerenols hamper the bundling of f-actin to form b-actin by adhering to the surface of f-actin, weakening the bundle-based cell stiffness.


Assuntos
Actinas/química , Fulerenos/química , Microscopia de Força Atômica , Citoesqueleto de Actina , Animais , Módulo de Elasticidade , Células HeLa , Humanos , Camundongos , Células NIH 3T3 , Espalhamento a Baixo Ângulo , Difração de Raios X
20.
Nanoscale ; 10(28): 13402-13409, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29971300

RESUMO

Designing nanosized multi-modality contrast agents for high-resolution imaging is challenging since most agents are only useful for single-mode imaging. In this work, we successfully synthesized biocompatible polyethylene glycol (PEG-) and l-glutamine (GLN-) modified Ba4Yb3F17:Lu3+,Gd3+ nanoparticles (LNPs@PEG@GLN) that can be employed as a multi-modality contrast agent. Fluorescence dye-modified LNPs@PEG@GLN nanoparticles can be used for computed tomography (CT), magnetic resonance imaging (MRI), and fluorescence imaging (FI). They display high X-ray absorption, outstanding T2-weighted imaging capability, and good fluorescence uptake. Furthermore, LNPs@PEG@GLN enhances contrast efficiencies for different imaging modalities in vivo. Interestingly, LNPs@PEG@GLN is a promising agent for CT angiography. These nanoparticles could be a promising contrast agent for multi-modality imaging and diagnosing vascular diseases.

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