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2.
Nanomaterials (Basel) ; 12(16)2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36014680

RESUMEN

High Power Impulse Magnetron Sputtering (HiPIMS) has generated a great deal of interest by offering significant advantages such as high target ionization rate, high plasma density, and the smooth surface of the sputtered films. This study discusses the deposition of copper nitride thin films via HiPIMS at different deposition pressures and then examines the impact of the deposition pressure on the structural and electrical properties of Cu3N films. At low deposition pressure, Cu-rich Cu3N films were obtained, which results in the n-type semiconductor behavior of the films. When the deposition pressure is increased to above 15 mtorr, Cu3N phase forms, leading to a change in the conductivity type of the film from n-type to p-type. According to our analysis, the Cu3N film deposited at 15 mtorr shows p-type conduction with the lowest resistivity of 0.024 Ω·cm and the highest carrier concentration of 1.43 × 1020 cm-3. Furthermore, compared to the properties of Cu3N films deposited via conventional direct current magnetron sputtering (DCMS), the films deposited via HiPIMS show better conductivity due to the higher ionization rate of HiPIMS. These results enhance the potential of Cu3N films' use in smart futuristic devices such as photodetection, photovoltaic absorbers, lithium-ion batteries, etc.

3.
J Nucl Cardiol ; 24(1): 19-28, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27813028

RESUMEN

BACKGROUND: The purpose of this study was to determine the feasibility of serial quantitative 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) to monitor the response of cardiac sarcoidosis to treatment. METHODS AND RESULTS: A total of 38 PET scan intervals (54 PET scans) were obtained in 16 patients with cardiac sarcoidosis who underwent serial FDG PET during treatment. FDG-avid lesions of the heart were interpreted quantitatively using 4 PET parameters: maximum standardized uptake value (SUVmax), partial volume corrected mean standardized uptake value (SUVmean), partial volume corrected metabolic volume product (MVP), and global metabolic volume product (gMVP). Clinical response to treatment (improved, stable, or progressive disease) was evaluated by clinical symptoms, NYHA class, and EKG in all the patients. SUVmax, SUVmean, MVP, and gMVP had significantly decreased value on repeat PET in patients who were either stable or showed clinical improvement between two serial PET scans, while none of them had significant change on repeat PET in patients who were clinically worse. Correlation analysis between PET findings and clinical assessment revealed that the changes of SUVmax and SUVmean on repeat PET were negatively correlated with patient's clinical outcome. CONCLUSION: Our results indicated that serial FDG PET is feasible to determine the extent of disease activity and to quantitatively assess the response of cardiac sarcoidosis to therapy.


Asunto(s)
Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/tratamiento farmacológico , Monitoreo de Drogas/métodos , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/tratamiento farmacológico , Femenino , Humanos , Inmunosupresores/uso terapéutico , Estudios Longitudinales , Masculino , Pronóstico , Radiofármacos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Técnica de Sustracción , Resultado del Tratamiento
4.
BMC Cancer ; 16: 179, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26940959

RESUMEN

BACKGROUND: The study is to evaluate the patterns of failure, toxicities and long-term outcomes of aggressive treatment using (18)F-FDG PET/CT-guided chemoradiation plannings for advanced cervical cancer with extensive nodal extent that has been regarded as a systemic disease. METHODS: We retrospectively reviewed 72 consecutive patients with (18)F-FDG PET/CT-detected widespread pelvic, para-aortic and/or supraclavicular lymph nodes treated with curative-intent PET-guided cisplatin-based extended-field dose-escalating intensity-modulated radiotherapy (IMRT) and adaptive high-dose-rate intracavitary 3D-brachytherapy between 2002 and 2010. The failure sites were specifically localized by comparing recurrences on fusion of post-therapy recurrent (18)F-FDG PET/CT scans to the initial PET-guided radiation plannings for IMRT and brachytherapy. RESULTS: The median follow-up time for the 72 patients was 66 months (range, 3-142 months). The 5-year disease-free survival rate calculated by the Kaplan-Meier method for the patients with extensive N1 disease with the uppermost PET-positive pelvic-only nodes (26 patients), and the patients with M1 disease with the uppermost PET-positive para-aortic (31 patients) or supraclavicular (15 patients) nodes was 78.5 %, and 41.8-50 %, respectively (N1 vs. M1, p = 0.0465). Eight (11.1 %), 18 (25.0 %), and 3 (4.2 %) of the patients developed in-field recurrence, out-of-field and/or distant metastasis, and combined failure, respectively. The 6 (8.3 %) local failures around the uterine cervix were all at the junction between IMRT and brachytherapy in the parametrium. The rate of late grade 3/4 bladder and bowel toxicities was 4.2 and 9.7 %, respectively. When compared to conventional pelvic chemoradiation/2D-brachytherapy during 1990-2001, the adoption of (18)F-FDG PET-guided extended-field dose-escalating chemoradiation plannings in IMRT and 3D-brachytherapy after 2002 appeared to provide higher disease-free and overall survival rates with acceptable toxicities in advanced cervical cancer patients. CONCLUSIONS: For AJCC stage M1 cervical cancer with supraclavicular lymph node metastases, curability can be achieved in the era of PET and chemo-IMRT. However, the main pattern of failure is still out-of-field and/or distant metastasis. In addition to improving systemic treatment, how to optimize and integrate the junctional doses between IMRT and 3D-brachytherapy in PET-guided plannings to further decrease local recurrence warrants investigation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones , Radioterapia de Intensidad Modulada , Tomografía Computarizada por Rayos X , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Braquiterapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Radioterapia de Intensidad Modulada/efectos adversos , Estudios Retrospectivos , Insuficiencia del Tratamiento , Resultado del Tratamiento , Neoplasias del Cuello Uterino/mortalidad
5.
Medicine (Baltimore) ; 95(2): e2515, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26765473

RESUMEN

Mediastinal nonseminomatous germ cell tumor (MNSGCT)-associated histiocytic proliferations are rare and rapidly fatal disorders. Standard treatment modalities have yet to be established.We report a case of MNSGCT-associated hemophagocytic syndrome that evolved into malignant histiocytosis/disseminated histiocytic sarcoma (MH/HS), which was initially treated with intravenous immunoglobulin, corticosteroids, and cyclosporine. Then, thalidomide plus cyclophosphamide, adriamycin, oncovin, prednisolone chemotherapy followed by alemtuzumab-containing reduced-intensity allogeneic peripheral blood stem cell transplantation (PBSCT) was used as salvage therapy.The severe constitutional symptoms and pancytopenia resolved shortly after thalidomide with cyclophosphamide, adriamycin, oncovin, prednisolone. After PBSCT, the patient developed steroid-dependent skin graft-versus-host disease, but maintained a functional life for 1.5 years. Rapid resolution of chronic graft-versus-host disease preceded the fulminant recurrence of hemophagocytic syndrome and MH/HS.Thalidomide plus chemotherapy followed by alemtuzumab-containing reduced intensity allogeneic PBSCT is effective in allaying MNSGCT-associated histiocytic disorders, but does not prevent eventual relapse. However, further posttransplant immune modulation should be developed to completely eradicate the residual MH/HS cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Sarcoma Histiocítico/tratamiento farmacológico , Neoplasias del Mediastino/complicaciones , Neoplasias de Células Germinales y Embrionarias/complicaciones , Trasplante de Células Madre de Sangre Periférica , Alemtuzumab , Anticuerpos Monoclonales Humanizados/uso terapéutico , Resultado Fatal , Sarcoma Histiocítico/etiología , Humanos , Inmunosupresores/uso terapéutico , Masculino , Neoplasias del Mediastino/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Talidomida/uso terapéutico , Trasplante Homólogo , Adulto Joven
6.
Clin Nucl Med ; 40(10): e465-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26204213

RESUMEN

PURPOSE: FDG PET that has been used is good for diagnosing asymptomatic colorectal cancer (CRC) recurrence in patients with elevated serum carcinoembryonic antigen (CEA) level. However, there is no reference level of CEA rise that would universally suggest the necessity of a PET study. The purpose of this retrospective study was to identify the high-risk group of CRC recurrence through an examination of the dynamics of the CEA level rise as a recurrence indicator. PATIENTS AND METHODS: Between July 2002 and May 2010, 112 patients (59 men, 53 women; age, 18-87 years) had FDG PET for suspicious CRC recurrence indicated by elevated CEA level. We reviewed the PET results and the medical records for recurrence verification and calculated the ratio of increase and the velocity of change in CEA levels for risk stratification. RESULTS: The patient-based sensitivity, specificity, and accuracy of PET are 96.6%, 91.3%, and 95.5%, respectively. The probability of recurrence positively correlated with the CEA level rise and the newly diagnosed disease stage. Carcinoembryonic antigen level greater than 13 ng/mL indicated significantly higher risks of recurrence. In patients with CEA level rise of 13 ng/mL or less, an increase over 3.34 times the individualized baseline also indicated high risks of recurrence. CONCLUSIONS: A posttreatment CEA level rise to greater than 13 ng/mL is suggestive of the optimal use of FDG PET, and so is a mild increase below 13 ng/mL at an increase rate over 3.34.


Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno Carcinoembrionario/sangre , Neoplasias Colorrectales/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Medicina de Precisión , Radiofármacos
7.
Clin Nucl Med ; 36(10): 867-71, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21892035

RESUMEN

PURPOSE: The purpose of this study is to evaluate the performance of gallium-67 scan (GS) and F-18 fluorodeoxyglucose (FDG) PET scan in lymphoma staging and recurrence detection by comparing the 2 imaging studies in the same patient. MATERIALS AND METHODS: A total of 42 patients from the period between July 2002 and May 2006 were included in this study. Of the 42 patients, 6 had Hodgkin disease and 36 had non-Hodgkin lymphomas. All of them underwent one or more FDG PET scans and also underwent corresponding GS performed within 7 days of FDG PET, for staging or detection of lymphoma recurrence. Among the non-Hodgkin lymphoma cases, 18 were diffuse large B-cell lymphoma, 10 were follicular center cell lymphoma, and 8 were of other types. Of the total 46 pairs of imaging performed in these 42 patients, 27 were for staging, and 19 for restaging after recurrence. RESULTS: In all these studies, FDG PET detected 230 lesion sites, whereas GS detected 85 lesion sites. All of the lesions detected by GS were noted on FDG PET, whereas GS detected only 37.0% of the lesions detected by FDG PET. Among the 27 studies for staging, FDG PET detected 120 lesions, whereas GS detected 68 lesions (56.7%). In the 19 images taken for relapse, FDG PET detected 110 lesions, whereas GS detected only 17 (15.5%). CONCLUSIONS: FDG PET is superior to GS in staging and detecting all types of lymphoma. The difference is notably more significant in recurrence detection.


Asunto(s)
Fluorodesoxiglucosa F18 , Linfoma/diagnóstico por imagen , Linfoma/patología , Tomografía de Emisión de Positrones , Femenino , Radioisótopos de Galio , Humanos , Masculino , Estadificación de Neoplasias , Recurrencia , Imagen de Cuerpo Entero
8.
Acta Radiol ; 50(4): 374-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19242830

RESUMEN

BACKGROUND: Pulmonary cryptococcosis is an uncommon cause of pulmonary nodules found by (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) scans. It is rarely reported but may mislead interpretation. PURPOSE: To describe the (18)F-FDG PET/CT findings of pulmonary cryptococcosis. MATERIAL AND METHODS: The (18)F-FDG PET/CT images of seven patients with pulmonary cryptococcosis were evaluated. RESULTS: The (18)F-FDG PET/CT exams showed single or multiple nodular lesions. The standardized uptake values (SUV) in early images varied significantly for the seven patients (ranging from 2.2 to 11.6). Delayed SUVs showed significant increases in four patients. CONCLUSION: Pulmonary cryptococcosis mimics primary or metastatic lung cancer on (18)F-FDG PET/CT scan. Tissue confirmation should be considered for any suspicious pulmonary nodules found on (18)F-FDG PET/CT scan with an SUV score higher than 2.5, in order to avoid overdiagnosis or overstaging.


Asunto(s)
Criptococosis/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
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