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1.
Phys Chem Chem Phys ; 25(14): 9817-9823, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36974934

RESUMO

By using first-principles calculations combined with the phonon Boltzmann transport equation, in this work, we systematically investigate the effect of magnetic order on the phonon and thermal transport properties of the intrinsic two dimensional magnet 2H-VSe2. The results show that 2H-VSe2 is dynamically stable in both paramagnetic and ferromagnetic phases, and the obvious discrepancy of characteristic frequencies of Raman-active phonon modes provides a reliable way to identify the magnetic phase. Meanwhile, our calculations also indicate that the magnetic order has a vital effect on the thermal transport properties. Around the Curie temperature (500 K), the thermal conductivity of 2H-VSe2 in the FM phase (16.3 W mK-1) is about four times larger than that in the PM phase (4.3 W mK-1), and such a difference could be maintained even when considering the temperature dependent force constants. By analyzing the phonon mode information and root mean square displacement, we reveal that large atomic interactions and suppressed phonon anharmonicity are the main roots for the enhanced thermal conductivity in the FM phase 2H-VSe2. These results further demonstrate that magnetic materials with a FM phase always host more excellent thermal transport properties than those with a PM phase, and shed light on the great potential applications of thermal switching devices based on 2H-VSe2.

2.
BMC Cancer ; 22(1): 863, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941565

RESUMO

BACKGROUND: There is no clear consensus on the benefits of adjuvant chemotherapy for tumor-node-metastasis (TNM) stage T1 (T1N0M0) breast cancer (BC). Our study investigated the effects of adjuvant chemotherapy on T1N0M0 BC patients. METHODS: Seventy-five thousand one hundred thirty-nine patients diagnosed with T1N0M0 BC were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate Cox analyses were performed to investigate the effects of adjuvant chemotherapy on T1a, T1b, and T1cN0M0 BC, including various tumor grades, and four molecular subtypes. Propensity score matching (PSM) was used to eliminate confounding factors and further compare the results between adjuvant chemotherapy and no adjuvant chemotherapy. Additionally, 545 T1N0M0 BC patients treated at the Northern Jiangsu People's Hospital were included as an independent external validation cohort. Univariate and multivariate Cox analyses were used to confirm the effects of adjuvant chemotherapy in T1a, T1b, and T1cN0M0 BC. Survival curves for the different tumor grades and molecular subtypes were plotted using the Kaplan-Meier method. RESULTS: Adjuvant chemotherapy demonstrated a statistically significant improvement in overall survival (OS) in T1b and T1c BC, but not in T1a BC. Within T1b BC, adjuvant chemotherapy was found to have effects on grade III, and hormone receptor + (HoR +)/human epidermal growth factor receptor 2 + (HER2 +), HoR-/HER2 + , and HoR-/HER2- molecular subtypes, respectively. Adjuvant chemotherapy was beneficial to OS for grade II/III and T1c BC. Identical results were obtained after PSM. We also obtained similar results with external validation cohort, except that adjuvant chemotherapy made a difference in grade II and T1b BC of the external validation dataset. CONCLUSIONS: Partial T1N0M0 BC patients with grade III T1bN0M0, patients with tumor grade II and III T1cN0M0, and excluding those with HoR + /HER2- subtype tumors, could obtain OS benefits from adjuvant chemotherapy.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Feminino , Humanos , Estadiamento de Neoplasias , Prognóstico , Pontuação de Propensão , Receptor ErbB-2/metabolismo
3.
J Colloid Interface Sci ; 583: 166-177, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002689

RESUMO

Photodynamic therapy (PDT) is a minimally invasive treatment strategy that uses photosensitizers and light in combination with oxygen to generate cytotoxic singlet oxygen (1O2) to kill cancer cells by necrosis or apoptosis. However, the treatment effects are still not satisfactory because of the tumor hypoxia and the PDT-induced oxygen consumption. Here, we have successfully synthesized dendritic mesoporous organosilica nanoparticles (MONs) with large center-radial pore structure that can be used to simultaneously encapsulate indocyanine green (ICG, <1 nm) and macromolecule catalase (CAT, 2.0 nm × 6.0 nm × 9.0 nm) to overcome the tumor hypoxia. Upon 808 nm laser irradiation, ICG as the organic NIR dye can generate highly cytotoxic singlet oxygen (1O2) and other reactive oxygen species (ROS) to kill cancer cells and realize photoacoustic (PA) imaging. The catalase can decompose the endogenous H2O2 in malignant cancerous cells into O2 bubble to simultaneously intensify the ultrasound (US) imaging signal and enhance PDT efficacy. These results indicate that the ICG-CAT@MONs holds great promise in multimodal photoacoustic / ultrasound image-guided tumor PDT therapy.


Assuntos
Nanopartículas , Nanosferas , Fotoquimioterapia , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Verde de Indocianina , Fármacos Fotossensibilizantes/uso terapêutico , Ultrassonografia
4.
World J Gastrointest Oncol ; 12(4): 492-502, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32368326

RESUMO

BACKGROUND: The relationship between microRNAs, such as miR-654-5p and miR-376b-3p, and the prognosis of colon cancer has not been studied until now. AIM: To evaluate the expression levels of miR-654-5p and miR-376b-3p and their clinical significance in colon cancer. METHODS: RT-qPCR was performed to evaluate miR-654-5p and miR-376b-3p expression in 34 pairs of colon cancer and adjacent noncancerous tissues. Subsequently, the association of miR-654-5p and miR-376b-3p expression with clinical factors or the survival of patients suffering from colon cancer was determined by using The Cancer Genome Atlas. RESULTS: miR-654-5p was upregulated and miR-376b-3p was downregulated in colon cancer tissues compared with adjacent noncancerous tissues (P < 0.001). Increased miR-654-5p and decreased miR-376b-3p expression levels were significantly associated with metastasis and clinical stage. Moreover, a univariate analysis demonstrated that colon cancer patients with high miR-654-5p or low miR-376b-3p expression (P = 0.044 and 0.007, respectively) had a poor overall survival rate. A multivariate analysis identified high miR-654-5p expression and low miR-376b-3p expression as independent predictors of poor survival in colon cancer patients. CONCLUSION: Upregulated miR-654-5p and downregulated miR-376b-3p may be associated with tumour progression in colon cancer, and these microRNAs may serve as independent prognostic markers for colon cancer.

5.
ACS Omega ; 4(19): 18118-18125, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31720514

RESUMO

Gold-based nanomaterials have attracted extensive interest for potential application in photothermal therapy (PTT) owing to their distinctive properties including high photothermal transduction, biocompatibility, and low cytotoxicity. Herein, assembled gold nanoparticle architecture-based photothermal conversion agents were synthesized by using polysaccharides (alginate dialdehyde, ADA) as both the cross-linker to induce self-assembly of diphenylalanine (FF) and the reducer for in situ reduction of Au3+ ions into Au nanoparticles (Au NPs). The extinction spectrum of the obtained self-assembled ADA-FF/Au nanospheres was finely modulated into a near-infrared region by controlling the growth of Au NPs inside the assemblies. The strong plasmonic coupling effect of the assembled Au NPs also leads to high photothermal conversion (η = 40%) of the ADA-FF/Au nanospheres, hence presenting good performance in PTT and photoacoustic imaging. This synthesis technique is promising to construct nanomaterials with desired functions for potential biomedical application by self-assembly of various nanocrystals in situ.

6.
Cancer Med ; 8(18): 7890-7902, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31663683

RESUMO

OBJECTIVE: There is limited information from population-based cancer registries regarding prognostic features of bilateral primary breast cancer (BPBC). METHODS: Female patients diagnosed with BPBC between 2004 and 2014 were randomly divided into training (n = 7740) and validation (n = 2579) cohorts from the Surveillance, Epidemiology, and End Results Database. We proposed five various models. Multivariate Cox hazard regression and competing risk analysis were to explore prognosis factors in training cohort. Competing risk nomograms were constructed to combine significant prognostic factors to predict the 3-year and the 5-year survival of patients with BPBC. At last, in the validation cohort, the new score performance was evaluated with respect to the area under curve, concordance index, net reclassification index and calibration curve. RESULTS: We found out that age, interval time, lymph nodes invasion, tumor size, tumor grade and estrogen receptor status were independent prognostic factors in both multivariate Cox hazard regression analysis and competing risk analysis. Concordance index in the model of the worse characteristics was 0.816 (95% CI: 0.791-0.840), of the bilateral tumors was 0.819 (95% CI: 0.793-0.844), of the worse tumor was 0.807 (0.782-0.832), of the first tumor was 0.744 (0.728-0.763) and of the second tumor was 0.778 (0.762-0.794). Net reclassification index of the 3-year and the 5-year between them was 2.7% and -1.0%. The calibration curves showed high concordance between the nomogram prediction and actual observation. CONCLUSION: The prognosis of BPBC depended on bilateral tumors. The competing risk nomogram of the model of the worse characteristics may help clinicians predict survival simply and effectively. Metachronous bilateral breast cancer presented poorer survival than synchronous bilateral breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Idoso , Biomarcadores Tumorais , Neoplasias da Mama/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Nomogramas , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Programa de SEER , Carga Tumoral
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