ABSTRACT
Killing tumor cells efficiently with photothermal therapy remains a huge challenge. In this study, we successfully prepared a novel polymer with photothermal conversion capability via a condensation reaction, and then subjected it to Polyethylene glycol (PEG) modification and ultrasonic nanocrystalline treatment to make it suitable forin vivophotothermal therapy applications. The conjugated polymer demonstrated good biocompatibility and photothermal conversion ability and was shown in cell experiments to be effective in killing tumor cells after laser irradiation. In addition, the conjugated polymer-based photothermal therapy, guided by photoacoustic real-time imaging and mediated by laser irradiation, of a tumor-bearing mouse model could effectively inhibit the growth of tumor tissue and demonstrated goodin vivobiosafety. Thus, photothermal therapy based on the conjugated polymer synthesized in this study provides a new idea and strategy for the treatment of lung cancer.
Subject(s)
Lung Neoplasms , Nanoparticles , Photoacoustic Techniques , Animals , Cell Line, Tumor , Lung Neoplasms/therapy , Mice , Nanoparticles/chemistry , Photoacoustic Techniques/methods , Phototherapy/methods , Photothermal Therapy , Polyethylene Glycols/chemistry , PolymersABSTRACT
To assess the clinical value of dual time point imaging (DTPI) fluorine-18fludeoxyglucose (18F-FDG) positron emission tomography (PET)/CT in differentiating malignancy and benign disease of patients with focally increased gastric uptake.Patients who present focally increased 18F-FDG uptake in gastric wall on conventional PET/CT imaging received delayed imaging. PET/CT scans were acquired at 1 and 2âhours (early and delayed imaging) after 18F-FDG injection. The maximum standardized uptake value (SUV) was calculated. The SUVmax of the early and delayed imaging acquisition were signed S1 and S2, respectively. The receiver operating characteristic curve (ROC) of the S1, S2, and the retention index (RI) were drawn to find the best cut-off point value for differential diagnosis. Sensitivity, specificity, Youden index, and the area under the curve (AUC) were calculated, respectively.From September 2010 to May 2015, 74 patients (56 male and 18 female; age of 57â±â12 years; range, 32-86 years) referring for areas of focally increased uptake of 18F-FDG in gastric wall received delayed imaging. The S1 was 5.0â±â1.4 (range, 1.9-11.3), and S2 was 5.9â±â2.7 (range, 1.0-16.3). The SUVmax were increased in 52 patients in delayed imaging, with 85% (44/52 cases) appeared malignant; decreased in 20 patients, and 90% (18/20 cases) were benign; 2 patients of benign had not changed. The change of SUVmax between malignant and benign was significant difference (tâ=â-5.785, Pâ=â0.000).Taking the S1, S2, and RI higher than 4.6%, 5.1%, and 13% as positive diagnostic criteria, the sensitivity were 65.2%,87.0%, and 87.0%, respectively; the specificity were 64.3%, 82.1%, and 89.3%; the Youden index were 0.332, 0.693, and 0.770; AUC were 0.635 (95% confidence intervals (95% CI) 0.507-0.764), 0.873 (95% CI, 0.786-0.961), and 0.923 (95% CI, 0.854-0.992).DTPI is more precise to distinct malignant from benign gastric diseases compared with conventional imaging, and it is readily accessible.