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1.
Small ; : e2401258, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794878

RESUMO

Manganese oxide-based aqueous zinc-ion batteries (ZIBs) are attractive energy storage devices, owing to their good safety, low cost, and ecofriendly features. However, various critical issues, including poor conductivity, sluggish reaction kinetics, and unstable structure still restrict their further development. Oxygen defect engineering is an effective strategy to improve the electrochemical performance of manganese oxides, but challenging in the accurate regulation of oxygen defects. In this work, an effective and controllable defect engineering strategy-controllable electrochemical lithium-ion intercalation - is proposed to tackle this issue. The incorporation of lithium ions and oxygen defects can promote the conductivity, lattice spacing, and structural stability of Mn2O3 (MO), thus improving its capacity (232.7 mAh g-1), rate performance, and long-term cycling stability (99.0% capacity retention after 3000 cycles). Interestingly, the optimal ratio of intercalated lithium-ion varies at different temperature or mass-loading of MO, which provides the possibility to customize diverse ZIBs to meet different application conditions. In addition, the fabricated ZIBs present good flexibility, superior safety, and admirable adaptability under extreme temperatures (-20-100 °C). This work provides an inspiration on the structural customization of metal oxide nanomaterials for diverse ZIBs, and sheds light on the construction of future portable electronics.

2.
Chem Soc Rev ; 52(22): 7687-7706, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37877319

RESUMO

Atomically thin sheets (e.g., graphene and monolayer molybdenum disulfide) are ideal optical and reaction platforms. They provide opportunities for deciphering some important and often elusive photocatalytic phenomena related to electronic band structures and photo-charges. In parallel, in such thin sheets, fine tuning of photocatalytic properties can be achieved. These include atomic-level regulation of electronic band structures and atomic-level steering of charge separation and transfer. Herein, we review the physics and chemistry of electronic band structures and photo-charges, as well as their state-of-the-art characterization techniques, before delving into their atomic-level deciphering and mastery on the platform of atomically thin sheets.

3.
Breast Cancer Res ; 25(1): 77, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37381020

RESUMO

BACKGROUND: The immunohistochemical test (IHC) of HER2 and HR can provide prognostic information and treatment guidance for invasive breast cancer patients. We aimed to develop noninvasive image signatures ISHER2 and ISHR of HER2 and HR, respectively. We independently evaluate their repeatability, reproducibility, and association with pathological complete response (pCR) to neoadjuvant chemotherapy. METHODS: Pre-treatment DWI, IHC receptor status HER2/HR, and pCR to neoadjuvant chemotherapy of 222 patients from the multi-institutional ACRIN 6698 trial were retrospectively collected. They were pre-separated for development, independent validation, and test-retest. 1316 image features were extracted from DWI-derived ADC maps within manual tumor segmentations. ISHER2 and ISHR were developed by RIDGE logistic regression using non-redundant and test-retest reproducible features relevant to IHC receptor status. We evaluated their association with pCR using area under receiver operating curve (AUC) and odds ratio (OR) after binarization. Their reproducibility was further evaluated using the test-retest set with intra-class coefficient of correlation (ICC). RESULTS: A 5-feature ISHER2 targeting HER2 was developed (AUC = 0.70, 95% CI 0.59 to 0.82) and validated (AUC = 0.72, 95% CI 0.58 to 0.86) with high perturbation repeatability (ICC = 0.92) and test-retest reproducibility (ICC = 0.83). ISHR was developed using 5 features with higher association with HR during development (AUC = 0.75, 95% CI 0.66 to 0.84) and validation (AUC = 0.74, 95% CI 0.61 to 0.86) and similar repeatability (ICC = 0.91) and reproducibility (ICC = 0.82). Both image signatures showed significant associations with pCR with AUC of 0.65 (95% CI 0.50 to 0.80) for ISHER2 and 0.64 (95% CI 0.50 to 0.78) for ISHER2 in the validation cohort. Patients with high ISHER2 were more likely to achieve pCR to neoadjuvant chemotherapy with validation OR of 4.73 (95% CI 1.64 to 13.65, P value = 0.006). Low ISHR patients had higher pCR with OR = 0.29 (95% CI 0.10 to 0.81, P value = 0.021). Molecular subtypes derived from the image signatures showed comparable pCR prediction values to IHC-based molecular subtypes (P value > 0.05). CONCLUSION: Robust ADC-based image signatures were developed and validated for noninvasive evaluation of IHC receptors HER2 and HR. We also confirmed their value in predicting treatment response to neoadjuvant chemotherapy. Further evaluations in treatment guidance are warranted to fully validate their potential as IHC surrogates.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Reprodutibilidade dos Testes , Estudos Retrospectivos , Razão de Chances
4.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33876189

RESUMO

Targeting tumor microenvironment (TME), such as immune checkpoint blockade (ICB), has achieved increased overall response rates in many advanced cancers, such as non-small cell lung cancer (NSCLC), however, only in a fraction of patients. To improve the overall and durable response rates, combining other therapeutics, such as natural products, with ICB therapy is under investigation. Unfortunately, due to the lack of systematic methods to characterize the relationship between TME and ICB, development of rational immune-combination therapy is a critical challenge. Here, we proposed a systems pharmacology strategy to identify resistance regulators of PD-1/PD-L1 blockade and develop its combinatorial drug by integrating multidimensional omics and pharmacological methods. First, a high-resolution TME cell atlas was inferred from bulk sequencing data by referring to a high-resolution single-cell data and was used to predict potential resistance regulators of PD-1/PD-L1 blockade through TME stratification analysis. Second, to explore the drug targeting the resistance regulator, we carried out the large-scale target fishing and the network analysis between multi-target drug and the resistance regulator. Finally, we predicted and verified that oxymatrine significantly enhances the infiltration of CD8+ T cells into TME and is a powerful combination agent to enhance the therapeutic effect of anti-PD-L1 in a mouse model of lung adenocarcinoma. Overall, the systems pharmacology strategy offers a paradigm to identify combinatorial drugs for ICB therapy with a systems biology perspective of drug-target-pathway-TME phenotype-ICB combination.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Quimioterapia Combinada , Feminino , Redes Reguladoras de Genes/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Quinolizinas/farmacologia , Quinolizinas/uso terapêutico , Sophora/química , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética
5.
Methods ; 205: 220-225, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35809769

RESUMO

U-Net has achieved great success in the task of medical image segmentation. It encodes and extracts information from several convolution blocks, and then decodes the feature maps to get the segmentation results. Our experiments show that in a multi-scale medical segmentation task, excessive downsampling will cause the model to ignore the small segmentation objects and thus fail to complete the segmentation task. In this work, we propose a more complete method Double-branch U-Net (2BUNet) to solve the multi-scale organ segmentation challenge. Our model is divided into four parts: main branch, tributary branch, information exchange module and classification module. The main advantages of the new model consist of: (1) Extracting information to improve model decoding capabilities using the complete encoding structure. (2) The information exchange module is added to the main branch and tributaries to provide regularization for the model, so as to avoid the large gap between the two paths. (3) Main branch structure for extracting major features of large organ. (4) The tributary structure is used to enlarge the image to extract the microscopic characteristics of small organ. (5) A classification assistant module is proposed to increase the class constraint for the output tensor. The comparative experiments show that our method achieves state-of-the-art performances in real scenes.


Assuntos
Diagnóstico por Imagem , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos
6.
Langenbecks Arch Surg ; 408(1): 262, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393198

RESUMO

PURPOSE: The reported threshold of a near-infrared fluorescence detection probe (FDP) for judging parathyroid glands (PGs) is based on the autofluorescence intensity relative to other non-PG tissues, making it unreliable when not enough reference tissues are measured. We aim to convert FDP into a more convenient tool for identifying accidentally resected PGs by quantitative measurements of autofluorescence in resected tissues. METHODS: It was a prospective study approved by the Institutional Review Board. The research was divided into two stages: (1) In order to calibrate the novel FDP system, autofluorescence intensity of different in / ex vivo tissues was measured and the optimal threshold was obtained using receiver operating characteristic (ROC) curve. (2) To further validate the effectiveness of the new system, detection rates of incidental resected PGs by pathology in the control group and by FDP in the experimental group were compared. RESULTS: Autofluorescence of PGs was significantly higher than that of non-PG tissue (43 patients, Mann-Whitney U test, p < 0.0001). An optimal threshold of sensitivity / specificity (78.8% and 85.1%) for discriminating PGs was obtained. The detection rates of experimental group (20 patients) and control group (33 patients) are 5.0% and 6.1% respectively (one-tailed Fisher's exact test, p = 0.6837), indicating the novel FDP system can achieve a similar proportion of PG detection compared with pathological examinations. CONCLUSIONS: The novel FDP system can be used as an easy-to-use adjunct for detecting PG accidentally resected intraoperatively before the tissues are sent for frozen sections during thyroidectomy surgeries. TRIAL REGISTRATION: Registration number: ChiCTR2200057957.


Assuntos
Glândulas Paratireoides , Tireoidectomia , Humanos , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/cirurgia , Estudos Prospectivos , Curva ROC , Estatísticas não Paramétricas
7.
Int J Mol Sci ; 24(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37445900

RESUMO

Potato is the world's fourth largest food crop. Due to limited arable land and an ever-increasing demand for food from a growing population, it is critical to increase crop yields on existing acreage. Soil salinization is an increasing problem that dramatically impacts crop yields and restricts the growing area of potato. One possible solution to this problem is the development of salt-tolerant transgenic potato cultivars. In this work, we review the current potato planting distribution and the ways in which it overlaps with salinized land, in addition to covering the development and utilization of potato salt-tolerant cultivars. We also provide an overview of the current progress toward identifying potato salt tolerance genes and how they may be deployed to overcome the current challenges facing potato growers.


Assuntos
Solanum tuberosum , Solanum tuberosum/genética , Tolerância ao Sal/genética , Solo
8.
Angew Chem Int Ed Engl ; 62(13): e202218016, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36593736

RESUMO

Two-dimensional (2D) transition metal dichalcogenides (TMDs), a rising star in the post-graphene era, are fundamentally and technologically intriguing for photocatalysis. Their extraordinary electronic, optical, and chemical properties endow them as promising materials for effectively harvesting light and catalyzing the redox reaction in photocatalysis. Here, we present a tutorial-style review of the field of 2D TMDs for photocatalysis to educate researchers (especially the new-comers), which begins with a brief introduction of the fundamentals of 2D TMDs and photocatalysis along with the synthesis of this type of material, then look deeply into the merits of 2D TMDs as co-catalysts and active photocatalysts, followed by an overview of the challenges and corresponding strategies of 2D TMDs for photocatalysis, and finally look ahead this topic.

9.
Small ; 18(44): e2203759, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36123132

RESUMO

Achieving efficient conversion of carbon dioxide (CO2 ) to formic acid (HCOOH) at mild conditions is a promising means to reduce greenhouse gas emission and mitigate the energy crisis. Herein, spin-polarized density functional theory calculations with van der Waals corrections (DFT+D3) are performed to analyze the catalytic activity of seven metals (Ti, Fe, Ni, Cu, Zn, In, and Sn) anchored on a tungsten ditelluride monolayer (M@WTe2 ) and screen favorable CO2 reduction pathways. These results demonstrate that Ni single atoms strongly bind to the WTe2 monolayer and exist in isolated form due to the high diffusion barriers. Also, Ni-anchored WTe2 monolayer (Ni@WTe2 ) possesses a considerably low limiting-potential (-0.11 V vs reversible hydrogen electrode) to convert CO2 to HCOOH due to moderate OCHO adsorption energy and a suppressed competing hydrogen evolution reaction (HER). Therefore, Ni@WTe2 monolayer is a promising electrocatalytic material for the CO2 reduction reaction (CO2 RR). This study sheds light on strategies of designing single metal atom anchored WTe2 catalysts for improved CO2 RR performances.

10.
Small ; 17(50): e2103052, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34719844

RESUMO

Manganese dioxide (MnO2 ), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase-activity relationship and the origin of the catalytic activity of these multiphase MnO2 . In this study, six types of MnO2 with crystal phases corresponding to α-, ß-, γ-, ε-, λ-, and δ-MnO2 are prepared, and their catalytic activity toward ozone-assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ-MnO2  > α-MnO2  > ε-MnO2  > γ-MnO2  > λ-MnO2  > ß-MnO2 . Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO2 is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies' density and the mobility of oxygen species, thus influencing the catalytic activity of MnO2 catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO2 catalysts for volatile organic pollutants' (VOCs) degradation.


Assuntos
Nanoestruturas , Ozônio , Catálise , Compostos de Manganês , Óxidos , Tolueno
11.
Cancer Cell Int ; 21(1): 529, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641869

RESUMO

BACKGROUND: Targeting tumor microenvironment (TME) may provide therapeutic activity and selectivity in treating cancers. Therefore, an improved understanding of the mechanism by which drug targeting TME would enable more informed and effective treatment measures. Glycyrrhiza uralensis Fisch (GUF, licorice), a widely used herb medicine, has shown promising immunomodulatory activity and anti-tumor activity. However, the molecular mechanism of this biological activity has not been fully elaborated. METHODS: Here, potential active compounds and specific targets of licorice that trigger the antitumor immunity were predicted with a systems pharmacology strategy. Flow cytometry technique was used to detect cell cycle profile and CD8+ T cell infiltration of licorice treatment. And anti-tumor activity of licorice was evaluated in the C57BL/6 mice. RESULTS: We reported the G0/G1 growth phase cycle arrest of tumor cells induced by licorice is related to the down-regulation of CDK4-Cyclin D1 complex, which subsequently led to an increased protein abundance of PD-L1. Further, in vivo studies demonstrated that mitigating the outgrowth of NSCLC tumor induced by licorice was reliant on increased antigen presentation and improved CD8+ T cell infiltration. CONCLUSIONS: Briefly, our findings improved the understanding of the anti-tumor effects of licorice with the systems pharmacology strategy, thereby promoting the development of natural products in prevention or treatment of cancers.

12.
Zhonghua Nan Ke Xue ; 27(7): 626-629, 2021 Jul.
Artigo em Zh | MEDLINE | ID: mdl-34914230

RESUMO

OBJECTIVE: To investigate the efficiency and complications of modified urethral reconstruction with lingual mucosa in the treatment of complicated anterior urethral stricture (CAUS). OBJECTIVE: To investigate the sexual experience and feelings of male patients with bladder cancer after transurethral resection of bladder tumor (TURBT), and provide some evidence for doctors and nurses in giving advice about the sexual problems of the patients. METHODS: This study included 32 male patients with bladder cancer after treated by TURBT from March 2020 to March 2021. The patients were aged 33-63 (51.91 ± 6.75) years, with a disease course of 13-38 (20.56 ± 7.49) month, and the interviews lasting 31-63 (39.06 ± 8.04) minutes. Among them, 10 (31.25%) lived in the rural area, 22 (68.75%) lived in the urban area, 12 (37.5%) had college education or above, 7 (21.88%) had senior high school education, 10 (31.25%) had junior high school education, and 3 (9.37%) had primary school education. Using the semi-structured method, we conducted interviews with the patients about their sexual experience and needs for sexual function rehabilitation and subjected the results of interviews to Colaizzi analysis. RESULTS: The interviews with the patients covered five topics, which showed intentional refraining from sexual life in 6 (18.75%) of the cases, worrying about hurting the partner by sexual contact in 8 (25%), neglecting sexual troubles in 8 (25%), negative emotions in 5 (15.63%), and expecting medical support in 17 (53.13%). CONCLUSIONS: Male patients with bladder cancer have poor sexual experience after TURBT. Doctors and nurses should inform the patients of potential sexual troubles during the treatment and follow-up, and provide relevant active intervention.


Assuntos
Procedimentos de Cirurgia Plástica , Neoplasias da Bexiga Urinária , Cistectomia , Progressão da Doença , Humanos , Masculino , Pesquisa Qualitativa , Neoplasias da Bexiga Urinária/cirurgia
13.
J Environ Sci (China) ; 93: 164-169, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32446452

RESUMO

There are good prospects for phosphorus recovery from excess sludge by vivianite crystallization while a large number of extracellular polymeric substances in sludge will have impact on vivianite precipitation. In this study, as a representative of extracellular polymeric substance, the effect of sodium alginate (SA) on phosphorus recovery by vivianite precipitation under different initial SA concentrations (0-800 mg/L), pH values (6.5-9.0) and Fe/P molar ratios (1:1-2.4:1) was investigated using synthetic wastewater. The results showed that SA in low concentrations (≤400 mg/L) had little inhibitory effect on the phosphorus recovery rate. However, when the concentration of SA was larger than 400 mg/L, the phosphorus recovery rate decreased significantly with increasing SA concentrations. The inhibition rate of 800 mg/L SA was about 3 times as large as that of 400 mg/L SA. It was worth noting that the inhibitory effect of SA on vivianite precipitation decreased with increasing initial pH and Fe/P molar ratios. Additionally, SA has no obvious influence on the composition of products, but the morphology of harvested crystals was transformed from branches to plates or rods in uneven sizes.


Assuntos
Fósforo , Eliminação de Resíduos Líquidos , Alginatos , Precipitação Química , Matriz Extracelular de Substâncias Poliméricas , Compostos Ferrosos , Fosfatos , Esgotos
14.
J Appl Clin Med Phys ; 20(11): 104-110, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31580532

RESUMO

The incidence of brain metastases is increasing and various treatment modalities exist for brain metastases. The aim of this study was to investigate the dosimetric quality and delivery efficiency of robotic radiosurgery (CyberKnife) for multiple brain metastases compared with C-arm linear accelerator (linac) based plans. C-arm linac based plans included intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and non-coplanar VMAT with 1, 3 and 5 non-coplanar arcs, respectively (NC1, NC3 and NC5). For 20 patients, six plans with a prescription dose of 30 Gy in three fractions were generated. The gradient index (GI), conformity index (CI), maximum dose (Dmax ) of organs at risk (OARs), normal brain tissue volume (V3 Gy -V24 Gy ), monitor units (MUs) and beam on time (BT) were evaluated. The GI of CyberKnife plans (3.60 ± 0.70) was lower than IMRT (6.21 ± 2.26, P < 0.05), VMAT (6.04 ± 1.93, P < 0.05), NC1 (5.16 ± 1.71, P < 0.05), NC3 (5.02 ± 1.59, P < 0.05) and NC5 (5.03 ± 1.72, P < 0.05). The CI of the VMAT plans (both coplanar and non-coplanar) was larger than IMRT and CK plans. The Dmax for most OARs of the CyberKnife plan was lower than the C-arm linac based plans, although some differences were not statistically significant. The normal brain tissue volume of CyberKnife plan was lower than the C-arm linac based plans, and the normal brain tissue volume of non-coplanar VMAT plans was lower than IMRT and VMAT plans at high-moderate dose level. However, the MUs and BT of CyberKnife plans was more than C-arm linac based plans. CyberKnife plan was better than C-arm linac based plans in protecting normal brain tissue and OARs for patients with multiple brain metastases. C-arm linac based plan with non-coplanar arc provided better protection of normal brain tissue than coplanar plan. However, the BT of CyberKnife plan was longer than C-arm linac based plans.


Assuntos
Neoplasias Encefálicas/cirurgia , Aceleradores de Partículas/instrumentação , Garantia da Qualidade dos Cuidados de Saúde/normas , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Encefálicas/secundário , Humanos , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
15.
J Appl Clin Med Phys ; 19(3): 142-148, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29603564

RESUMO

Monte Carlo (MC) simulation, as the most accurate dose calculation algorithm, is available in the MultiPlan treatment planning system for Cyberknife. The main purpose of this work was to perform experiments to thoroughly investigate the accuracy of the MC dose calculation algorithm. Besides the basic MC beam commissioning, two test scenarios were designed. First, single beam tests were performed with a solid water phantom to verify the MC source model in simple geometry. Then, a lung treatment plan on a CIRS thorax phantom was created to mimic the clinical patient treatment. The plan was optimized and calculated using ray tracing (RT) algorithm and then recalculated using MC algorithm. Measurements were performed in both a homogeneous phantom and a heterogeneous phantom (CIRS). Ion-chamber and radiochromic film were used to obtain absolute point dose and dose distributions. Ion-chamber results showed that the differences between measured and MC calculated dose were within 3% for all tests. On the film measurements, MC calculation results showed good agreements with the measured dose for all single beam tests. As for the lung case, the gamma passing rate between measured and MC calculated dose was 98.31% and 97.28% for homogeneous and heterogeneous situation, respectively, using 3%/2 mm criteria. However, RT algorithm failed with the passing rate of 79.25% (3%/2 mm) for heterogeneous situation. These results demonstrated that MC dose calculation algorithm in the Multiplan system is accurate enough for patient dose calculation. It is strongly recommended to use MC algorithm in heterogeneous media.


Assuntos
Algoritmos , Método de Monte Carlo , Imagens de Fantasmas , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/normas , Neoplasias Torácicas/cirurgia , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
16.
J Appl Clin Med Phys ; 18(6): 49-57, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28905514

RESUMO

PURPOSE: To investigate the dosimetric characteristics of the new GMS BT-125-1 125 I radioactive seed, including dose rate constant, radial dose functions, and anisotropy functions. METHODS: Dosimetric parameters of GMS BT-125-1 125 I seed including dose rate constant, radial dose functions, and anisotropy functions were calculated using the Monte Carlo code of MCNP5, and measured with thermoluminescent dosimeters (TLDs). The results were compared with those of PharmaSeed BT-125-1, PharmaSeed BT-125-2 125 I, and model 6711 125 I seeds. RESULTS: The dose rate constant of GMS BT-125-1 125 I seed was 0.959 cGy·h-1·U-1, with the difference of 0.94%, 0.83%, and 0.73% compared with the PharmaSeed BT-125-1 125 I seed, PharmaSeed BT-125-2 125 I seed, and Model 6711 125 I seed, respectively. For radial dose function, the differences between the Monte Carlo and the experimental g(r) results were mostly within 10%. Monte Carlo results of g(r) for GMS BT-125-1 125 I seed were found in agreement (within 3.3%) with corresponding results for the PharmaSeed BT-125-2 125 I seed. The largest differences were 8.1% and 6.2% compared with PharmaSeed BT-125-1 125 I seed and model 6711 125 I seed, respectively. For anisotropy function, the difference between GMS BT-125-1 125 I seed and PharmaSeed BT-125-2 125 I seed was typically <10%. CONCLUSIONS: The measured dose rate constant, radial dose functions, and two-dimensional anisotropy functions for the GMS BT-125-1 125 I seed showed good agreement with the Monte Carlo results. The dose rate constant of the GMS BT-125-1 125 I seed is similar to that of the PharmaSeed BT-125-1 125 I seed, the PharmaSeed BT-125-2 125 I seed, and the model 6711 125 I seed. For radial dose functions and two-dimensional anisotropy functions, the GMS BT-125-1 125 I seed is similar to the PharmaSeed BT-125-2 125 I seed but different from the PharmaSeed BT-125-1 125 I seed and the model 6711 125 I seed.


Assuntos
Simulação por Computador , Radioisótopos do Iodo/uso terapêutico , Método de Monte Carlo , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Anisotropia , Humanos , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Dosimetria Termoluminescente
17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(6): 952-6, 2015 Dec 18.
Artigo em Zh | MEDLINE | ID: mdl-26679656

RESUMO

OBJECTIVE: To evaluate the six-degree setup errors of tumors of cervical vertebra, thoracic vertebra and lumbar vertebra by image guided radiotherapy. METHODS: From May 2013 to June 2014, 30 patients with spinal malignant tumors(10 patients of cervical vertebra, thoracic vertebra and lumbar vertebra respectively) were treated with Elekata Synergy accelerator (Elekta company,Sweden). Six-degree set up errors were corrected using HexaPODTMevoRT bed under image of on board cone beam computed tomography (CBCT) guided. All the patients received kilovoltage CBCT before receiving radiotherapy and after correction. The acquired images were co-registered with planning CT with bone window. The data of 838 CT images were analyzed and the errors of translational directions X(lateral), Y(lngitudinal),Z(vertical)and rotational directions RX(pitch), RY(roll), RZ(yaw) were recorded. The data were compared by t-test using SPSS 13.0. RESULTS: The absolute translational setup errors in X, Y and Z axes of cervical vertebra before correction were (1.71 ± 0.10) mm, (1.81 ± 0.11) mm and (1.94 ± 0.09) mm respectively: (3.17 ± 0.19) mm, (4.26 ± 0.28) mm and (2.18 ± 0.12) mm for thoracic vertebra, and (2.69 ± 0.24) mm, (3.33 ± 0.26) mm and (2.86 ± 0.21) mm for lumbar vertebra. The residual setup errors in X, Y and Z axes of cervical vertebra were (0.5 ± 2.4) mm,(0.01 ± 2.4) mm and (2.4 ± 1.4) mm, respectively after correction;(1.17 ± 0.11) mm,(0.26 ± 0.30) mm and (0.08 ± 0.12) mm for thoracic vertebra and (1.09 ± 0.24) mm,(2.03 ± 1.26) mm and (0.06 ± 0.51) mm for lumbar vertebra. The t-test of paired data of set up errors before and after CBCT showed significant difference in three translational directions of cervical vertebra and thoracic vertebra, only Z(t=-3.518,P<0.001) for lumbar vertebra. The absolute rotational setup errors in RX,RY and RZ axes of cervical vertebra before correction were 0.67° ± 0.04°,1.06° ± 0.06° and 0.78° ± 0.05° respectively. 0.62° ± 0.05°, 0.75° ± 0.06°, and 0.84° ± 0.06° for thoracic vertebra, 0.59° ± 0.06°, 0.80° ± 0.07°, and 0.73° ± 0.06° for lumbar vertebra. The rotational directions RX, RY and RZ axes of cervical vertebra were 0.27° ± 0.14°, 1.20° ± 0.04° and 0.28° ± 0.05° respectively; 0.02° ± 0.20°, 0.05°±0.26° and 0.64° ± 0.16° for thoracic vertebra and 0.09° ± 0.26°, 0.50°±0.05°,and 0.03°±0.16° for lumbar vertebra. The t-test of paired data of set up errors before and after CBCT showed significant difference in three rotational directions of cervical vertebra and lumbar vertebra, only RY(t=7.106, P<0.001)for thoracic vertebra. All the patients acquired pain relief and there was no radiation-induced toxicity detected clinically during a median follow-up of 6 months. CONCLUSION: Six-degree set up errors of spine tumors were corrected effectively with HexaPODTMevoRT bed under CBCT image guided and its feasibility in day-to-day clinical practice has been demonstrated.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Neoplasias da Coluna Vertebral/radioterapia , Vértebras Cervicais/patologia , Tomografia Computadorizada de Feixe Cônico , Humanos , Vértebras Lombares/patologia , Lesões por Radiação , Vértebras Torácicas/patologia
18.
ACS Nano ; 18(20): 12598-12609, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38723158

RESUMO

This review presents an overview of the application of electrochemical liquid-phase transmission electron microscopy (ELP-TEM) in visualizing rechargeable battery reactions. The technique provides atomic-scale spatial resolution and real-time temporal resolution, enabling direct observation and analysis of battery materials and processes under realistic working conditions. The review highlights key findings and insights obtained by ELP-TEM on the electrochemical reaction mechanisms and discusses the current limitations and future prospects of ELP-TEM, including improvements in spatial and temporal resolution and the expansion of the scope of materials and systems that can be studied. Furthermore, the review underscores the critical role of ELP-TEM in understanding and optimizing the design and fabrication of high-performance, long-lasting rechargeable batteries.

19.
Sci Rep ; 14(1): 15424, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965404

RESUMO

In the feedrate scheduling of complex curve direct interpolation, dynamic constraints such as axis acceleration and jerk are related to the actual state of the tool. Most existing methods convert dynamic constraints to velocity constraints at sampling points. However, it cannot guarantee the dynamic constraints are satisfied between sampling points. Addressing the issue, this paper proposes a dynamic look-ahead feedrate scheduling method based on sliding mode velocity control, which generates the motion command considering dynamic constraints in every interpolation cycle. To dynamically generate commands based on the current tool state, the acceleration and deceleration method based on sliding mode velocity control has been proposed, which can control tool state to transition to the command state with any initial state. To ensure sufficient distance for acceleration and deceleration, this paper uses braking distance to dynamically estimate the look-ahead distance. Then the minimum value within the look-ahead interval is selected as the command velocity for this scheduling cycle and the actual motion command is determined based on the dynamic constraints of each axis. Simulation and experiment results prove that compared with the existing method, this method effectively reduces the overshoot of dynamic constraints without significantly increasing the machining time. The analysis of real-time computation time has demonstrated the potential of the method proposed in this paper for real-time applications.

20.
Chin Med J (Engl) ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945693

RESUMO

ABSTRACT: Chronic hepatitis B virus (HBV) infection is a global public health concern. Existing antiviral drugs, including nucleos(t)ide analogs and interferon-α, can suppress HBV replication and improve the prognosis. However, the persistence of covalently closed circular DNA (cccDNA), the integration of HBV-DNA into the host genome, and compromised immune responses impede the successful treatment of hepatitis B. While achieving a functional cure of HBV remains elusive with the current treatment methods, this is the goal of new therapeutic approaches. Therefore, developing novel antiviral drugs is necessary for achieving a functional or complete cure for chronic hepatitis B. In recent years, substantial progress has been made in drug discovery and development for HBV infection. Direct-acting antiviral agents such as entry inhibitors, capsid assembly modulators, subviral particle release inhibitors, cccDNA silencers, and RNA interference molecules have entered clinical trials. In addition, several immunomodulatory agents, including toll-like receptor agonists, therapeutic vaccines, checkpoint inhibitors, and monoclonal antibodies, are also making their way toward clinical use. In this review, we summarize the recent progress and limitations of chronic hepatitis B treatment and discuss perspectives on approaches to achieving functional cure. Although it will take some time for these new antiviral drugs to be widely used in clinical practice, combination therapy may become a preferable treatment option in the future.

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