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1.
J Nucl Med Technol ; 51(2): 133-139, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37192822

RESUMO

Our purpose was to investigate the utility of 18F-FDG PET/MRI and serial blood work to detect early inflammatory responses and cardiac functionality changes at 1 mo after radiation therapy (RT) in patients with left-sided breast cancer. Methods: Fifteen left-sided breast cancer patients who enrolled in the RICT-BREAST study underwent cardiac PET/MRI at baseline and 1 mo after standard RT. Eleven patients received deep-inspiration breath-hold RT, whereas the others received free-breathing RT. A list-mode 18F-FDG PET scan with glucose suppression was acquired. Myocardial inflammation was quantified by the change in 18F-FDG SUVmean (based on body weight) and analyzed on the basis of the myocardial tissue associated with the left anterior descending, left circumflex, or right coronary artery territories. MRI assessments, including left ventricular functional and extracellular volumes (ECVs), were extracted from T1 (before and during a constant infusion of gadolinium) and cine images, respectively, acquired simultaneously during the PET acquisition. Cardiac injury and inflammation biomarker measurements of high-sensitivity troponin T, high-sensitivity C-reactive protein, and erythrocyte sedimentation rate were measured at the 1-mo follow-up and compared with preirradiation values. Results: At the 1-mo follow-up, a significant increase (10%) in myocardial SUVmean in left anterior descending segments (P = 0.04) and ECVs in slices at the apex (6%) and base (5%) was detected (P ≤ 0.02). Further, a significant reduction in left ventricular stroke volume (-7%) was seen (P < 0.02). No significant changes in any circulating biomarkers were seen at follow-up. Conclusion: Myocardial 18F-FDG uptake and functional MRI, including stroke volume and ECVs, were sensitive to changes at 1 mo after breast cancer RT, with findings suggesting an acute cardiac inflammatory response to RT.


Assuntos
Neoplasias da Mama , Neoplasias Unilaterais da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Fluordesoxiglucose F18 , Coração/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Arritmias Cardíacas , Imageamento por Ressonância Magnética
3.
Nat Commun ; 10(1): 5772, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852891

RESUMO

Crystalline-silicon solar cells have dominated the photovoltaics market for the past several decades. One of the long standing challenges is the large contribution of silicon wafer cost to the overall module cost. Here, we demonstrate a simple process for making high-purity solar-grade silicon films directly from silicon dioxide via a one-step electrodeposition process in molten salt for possible photovoltaic applications. High-purity silicon films can be deposited with tunable film thickness and doping type by varying the electrodeposition conditions. These electrodeposited silicon films show about 40 to 50% of photocurrent density of a commercial silicon wafer by photoelectrochemical measurements and the highest power conversion efficiency is 3.1% as a solar cell. Compared to the conventional manufacturing process for solar grade silicon wafer production, this approach greatly reduces the capital cost and energy consumption, providing a promising strategy for low-cost silicon solar cells production.

4.
BMC Cancer ; 19(1): 1206, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31829203

RESUMO

BACKGROUND: Stereotactic ablative radiotherapy (SABR) has become an established treatment option for medically-inoperable early-stage (Stage I-IIA) non-small cell lung cancer (ES-NSCLC). SABR is able to obtain high rates of local control with low rates of symptomatic toxicity in this patient population. However, in a subset of patients with fibrotic interstitial lung disease (ILD), elevated rates of SABR-related toxicity and mortality have been described. The Assessment of Precision Irradiation in Early Non-Small Cell Lung Cancer and Interstitial Lung Disease (ASPIRE-ILD) study will conduct a thorough prospective evaluation of the clinical outcomes, toxicity, changes in diagnostic test parameters and patient-related outcomes following SABR for ES-NSCLC for patients with fibrotic ILD. METHODS: ASPIRE-ILD is a single-arm Phase II prospective study. The accrual target is 39 adult patients with T1-2N0M0 non-small cell lung cancer with co-existing ILD who are not candidates for surgical excision. Pathological confirmation of diagnosis is strongly recommended but not strictly required. Enrolled patients will be stratified by ILD-related mortality risk. The starting SABR dose will be 50 Gy in 5 fractions every other day (biologically effective dose: 100 Gy10 or 217 Gy3), but the radiation dose can be de-escalated up to two times to 50 Gy in 10 fractions daily (75 Gy10 or 133 Gy3) and 45 Gy in 15 fractions daily (58 Gy10 or 90 Gy3). Dose de-escalation will occur if 2 or more of the first 7 patients in a cohort experiences grade 5 toxicity within 6 months of treatment. Similarly, dose de-escalation can also occur if 2 or more of the first 7 patients with a specific subtype of ILD experiences grade 5 toxicity within 6 months of treatment. The primary endpoint is overall survival. Secondary endpoints include toxicity (CTC-AE 4.0), progression-free survival, local control, patient-reported outcomes (cough severity and quality of life), rates of ILD exacerbation and changes in pulmonary function tests/high-resolution computed tomography findings post-SABR. DISCUSSION: ASPIRE-ILD will be the first prospective study specifically designed to comprehensively evaluate the effectiveness and safety of SABR for ES-NSCLC in patients with co-existing ILD. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03485378. Date of registration: April 2, 2018.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Doenças Pulmonares Intersticiais/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Doenças Pulmonares Intersticiais/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
5.
Angew Chem Int Ed Engl ; 56(47): 15078-15082, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28902971

RESUMO

Electrodeposition of Si films from a Si-containing electrolyte is a cost-effective approach for the manufacturing of solar cells. Proposals relying on fluoride-based molten salts have suffered from low product quality due to difficulties in impurity control. Here we demonstrate the successful electrodeposition of high-quality Si films from a CaCl2 -based molten salt. Soluble SiIV -O anions generated from solid SiO2 are electrodeposited onto a graphite substrate to form a dense film of crystalline Si. Impurities in the deposited Si film are controlled at low concentrations (both B and P are less than 1 ppm). In the photoelectrochemical measurements, the film shows p-type semiconductor character and large photocurrent. A p-n junction fabricated from the deposited Si film exhibits clear photovoltaic effects. This study represents the first step to the ultimate goal of developing a cost-effective manufacturing process for Si solar cells based on electrodeposition.

6.
Int J Radiat Oncol Biol Phys ; 95(3): 1075-1082, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27130788

RESUMO

PURPOSE: To use 4-dimensional computed tomography (4D-CT) imaging to predict the level of uncertainty in cardiac dose estimates of the left anterior descending artery that arises due to breathing motion during radiation therapy for left-sided breast cancer. METHODS AND MATERIALS: The fast helical CT (FH-CT) and 4D-CT of 30 left-sided breast cancer patients were retrospectively analyzed. Treatment plans were created on the FH-CT. The original treatment plan was then superimposed onto all 10 phases of the 4D-CT to quantify the dosimetric impact of respiratory motion through 4D dose accumulation (4D-dose). Dose-volume histograms for the heart, left ventricle (LV), and left anterior descending (LAD) artery obtained from the FH-CT were compared with those obtained from the 4D-dose. RESULTS: The 95% confidence interval of 4D-dose and FH-CT differences in mean dose estimates for the heart, LV, and LAD were ±0.5 Gy, ±1.0 Gy, and ±8.7 Gy, respectively. CONCLUSION: Fast helical CT is a good approximation for doses to the heart and LV; however, dose estimates for the LAD are susceptible to uncertainties that arise due to intrafraction breathing motion that cannot be ascertained without the additional information obtained from 4D-CT and dose accumulation. For future clinical studies, we suggest the use of 4D-CT-derived dose-volume histograms for estimating the dose to the LAD.


Assuntos
Vasos Coronários/efeitos da radiação , Fracionamento da Dose de Radiação , Tomografia Computadorizada Quadridimensional/métodos , Órgãos em Risco/efeitos da radiação , Mecânica Respiratória , Neoplasias Unilaterais da Mama/radioterapia , Adulto , Feminino , Humanos , Masculino , Movimento (Física) , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Neoplasias Unilaterais da Mama/diagnóstico por imagem
7.
J Neurooncol ; 128(3): 431-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27084705

RESUMO

We examined functional outcomes and quality of life of whole brain radiotherapy (WBRT) with integrated fractionated stereotactic radiotherapy boost (FSRT) for brain metastases treatment. Eighty seven people with 1-3 brain metastases (54/87 lung primary, 42/87 single brain metastases) were enrolled on this Phase II trial of WBRT (30 Gy/10) + simultaneous FSRT, (60 Gy/10). Median overall follow-up and survival was 5.4 months, 6 month actuarial intra-lesional control was 78 %; only 1 patient exhibited grade 4 toxicity (worsened seizures); most treatment related toxicity was grade 1 or 2; 2/87 patients demonstrated asymptomatic radiation necrosis on follow-up imaging. Mean (Min-Max) baseline KPS, Mini Mental Status Exam (MMSE) and FACT-BR quality of life were 83 (70-100), 28 (21-30) and 143 (98-153). Lower baseline MMSE (but not KPS or FACT-Br) was associated with worse survival after adjusting for age, number of metastases, primary and extra-cranial disease status. Crude rates of deterioration (>10 points decrease from baseline for KPS and FACT-Br, MMSE fall to <27) ranged from 26 to 38 % for KPS, 32-59 % for FACT-Br and 0-16 % for MMSE depending on the time-point assessed with higher rates generally noted at earlier time points (≤6 months post-treatment). Using a linear mixed models analysis, significant declines from baseline were noted for KPS and FACT-Br (largest effects at 6 weeks to 3 months) with no significant change in MMSE. The effects on function and quality of life of this integrated treatment of WBRT + simultaneous FSRT were similar to other published series combining WBRT + radiosurgery.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Humanos , Modelos Lineares , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Seio Sagital Superior , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Patholog Res Int ; 2011: 504940, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21559203

RESUMO

Most cancer centers now perform sentinel node (SN) biopsies. The limited number of SNs sampled compared with an axillary dissection has allowed more comprehensive lymph node analysis resulting in increased detection of micrometastases. Many node-negative cases are now reclassified as micrometastatic. Recent research on SN biopsy focuses on whether axillary dissection is always necessary when the SN is positive. Some subgroups of patients have a higher risk of more nodal metastases when completion axillary dissections were performed. This paper summarizes the different studies and examines what are the clinically relevant items to report on SN node pathology: volume or size of nodal metastasis, location within the node, extranodal extension, number of involved SN(s) and non-SN(s), total number of SN, and total number of nodes on axillary dissection, if performed.

9.
BMC Cancer ; 7: 31, 2007 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-17311683

RESUMO

BACKGROUND: In general, prognosis and impact of prognostic/predictive factors are assessed with Kaplan-Meier plots and/or the Cox proportional hazard model. There might be substantive differences from the results using these models for the same patients, if different statistical methods were used, for example, Boag log-normal (cure-rate model), or log-normal survival analysis. METHODS: Cohort of 244 limited-stage small-cell lung cancer patients, were accrued between 1981 and 1998, and followed to the end of 2005. The endpoint was death with or from lung cancer, for disease-specific survival (DSS). DSS at 1-, 3- and 5-years, with 95% confidence limits, are reported for all patients using the Boag, Kaplan-Meier, Cox, and log-normal survival analysis methods. Factors with significant effects on DSS were identified with step-wise forward multivariate Cox and log-normal survival analyses. Then, DSS was ascertained for patients with specific characteristics defined by these factors. RESULTS: The median follow-up of those alive was 9.5 years. The lack of events after 1966 days precluded comparison after 5 years. DSS assessed by the four methods in the full cohort differed by 0-2% at 1 year, 0-12% at 3 years, and 0-1% at 5 years. Log-normal survival analysis indicated DSS of 38% at 3 years, 10-12% higher than with other methods; univariate 95% confidence limits were non-overlapping. Surgical resection, hemoglobin level, lymph node involvement, and superior vena cava (SVC) obstruction significantly impacted DSS. DSS assessed by the Cox and log-normal survival analysis methods for four clinical risk groups differed by 1-6% at 1 year, 15-26% at 3 years, and 0-12% at 5 years; multivariate 95% confidence limits were overlapping in all instances. CONCLUSION: Surgical resection, hemoglobin level, lymph node involvement, and superior vena cava (SVC) obstruction all significantly impacted DSS. Apparent DSS for patients was influenced by the statistical methods of assessment. This would be clinically relevant in the development or improvement of clinical management strategies.


Assuntos
Carcinoma de Células Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Modelos Estatísticos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Pequenas/secundário , Carcinoma de Células Pequenas/terapia , Estudos de Coortes , Comorbidade , Intervalos de Confiança , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Saskatchewan/epidemiologia , Síndrome da Veia Cava Superior/epidemiologia , Análise de Sobrevida , Taxa de Sobrevida
10.
Int J Radiat Oncol Biol Phys ; 52(1): 68-74, 2002 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11777623

RESUMO

PURPOSE: To investigate the therapeutic usefulness and cost-effectiveness of prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer (SCLC) who had achieved a complete remission. METHODS: A retrospective chart review was undertaken of all patients diagnosed in Saskatchewan with SCLC between 1987 and 1998 inclusive. Patients who achieved a complete remission were divided into two groups, depending on whether they underwent PCI (PCI+ and PCI-, respectively). The quality-of-life-adjusted survival was estimated by the Q-TWiST method (quality time without symptoms and toxicity). The mean incremental costs per month of incremental OS were calculated in a cost-effectiveness analysis. RESULTS: Among the 98 complete remission patients, the median OS for PCI+ and PCI- patients was 20.0 and 19.0 months, respectively (p > 0.05, nonsignificant). The median disease-free survival was 14.7 and 10.0 months, respectively (p < 0.05). The difference in the mean Q-TWiST survival was significant (p < 0.01). The mean marginal cost was $18,834/PCI+ patient and $17,885/PCI- patient (p > 0.05, nonsignificant). The cost-effectiveness ratio was $70/mo of incremental OS if u(tox) and u(rel) (the utility coefficients to reflect the value of time in health states of toxicity and relapse) were assumed to be 1.0. CONCLUSION: PCI is a cost-effective treatment that improves the quality-of-life-adjusted survival for patients with a complete remission of SCLC.


Assuntos
Neoplasias Encefálicas/prevenção & controle , Carcinoma de Células Pequenas/prevenção & controle , Irradiação Craniana , Neoplasias Pulmonares , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/secundário , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/secundário , Intervalos de Confiança , Análise Custo-Benefício , Irradiação Craniana/economia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Qualidade de Vida , Indução de Remissão , Estudos Retrospectivos , Taxa de Sobrevida
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