The study aimed at identifying patient-specific dosimetric and nondosimetric factors predicting outcome of non-Hodgkin lymphoma patients after 131I-tositumomab radioimmunotherapy for potential use in treatment planning. Methods Tumor-absorbed dose measures were estimated for 130 tumors in 39 relapsed or refractory non-Hodgkin lymphoma patients by coupling SPECT/CT imaging with the Dose Planning Method (DPM) Monte Carlo code. Equivalent biologic effect was calculated to assess the biologic effects of nonuniform absorbed dose including the effects of the unlabeled antibody. Evaluated nondosimetric covariates included histology, presence of bulky disease, and prior treatment history. Tumor level outcome was based on volume shrinkage assessed on follow-up CT. Patient level outcome measures were overall response (OR), complete response (CR), and progression-free survival (PFS), determined from clinical assessments that included PET/CT. Results The estimated mean tumor-absorbed dose had a median value of 275 cGy (range, 94–711 cGy). A high correlation was observed between tracer-predicted and therapy-delivered mean tumor-absorbed doses (P < 0.001; r = 0.85). In univariate tumor-level analysis, tumor shrinkage correlated significantly with almost all of the evaluated dosimetric factors, including equivalent biologic effect. Regression analysis showed that OR, CR, and PFS were associated with the dosimetric factors and equivalent biologic effect. Both mean tumor-absorbed dose (P = 0.025) and equivalent biologic effect (P = 0.035) were significant predictors of PFS whereas none of the nondosimetric covariates were found to be statistically significant factors affecting PFS. The most important finding of the study was that in Kaplan–Meier curves stratified by mean dose, longer PFS was observed in patients receiving mean tumor-absorbed doses greater than 200 cGy than in those receiving 200 cGy or less (median PFS, 13.6 vs. 1.9 mo for the 2 dose groups; log-rank P < 0.0001). Conclusion A higher mean tumor-absorbed dose was significantly predictive of improved PFS after 131I-tositumomab radioimmunotherapy. Hence tumor-absorbed dose, which can be estimated before therapy, can potentially be used to design radioimmunotherapy protocols to improve efficacy.

Nuclear medicine imaging of endocrine disorders takes advantage of unique cellular properties of endocrine organs and tissues that can be depicted by targeted radiopharmaceuticals. Detailed functional maps of biodistributions of radiopharmaceutical uptake can be displayed in three-dimensional tomographic formats, using single photon emission computed tomography (CT) that can now be directly combined with simultaneously acquired cross-sectional anatomic maps derived from CT. The integration of function depicted by scintigraphy and anatomy with CT has synergistically improved the efficacy of nuclear medicine imaging across a broad spectrum of clinical applications, which include some of the oldest imaging studies of endocrine dysfunction.

Much attention has been directed toward the development of new energetic materials to achieve the increasingly demanding performance of high-speed propulsion systems. Nanothermite is one of the main approaches for the development of new energetic materials by the close integration of oxidizer and metal fuel. This study is devoted to evaluating the impact of different carbon nanomaterials (graphene oxide, reduced graphene oxide, carbon nanotubes, and carbon nanofibers) on the thermal behavior of nanothermites based on potassium perchlorate and nano aluminium powder. Nanothermite compositions were prepared using a conventional sonication method. The morphology of nanothermites was characterized by a scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS), which confirmed that the nanoparticles are homogeneously dispersed without agglomeration. The structure of nanothermite was also characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), and Raman spectroscopy. The impact of carbon nanomaterials on the combustion behavior of nanothermite was evaluated by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and bomb calorimetry. There was good agreement between results from DSC and bomb calorimetry. In general, the total heat released improved with the addition of carbon nanomaterials and particularly graphene oxide, which generated the highest increase in the heat of combustion. In addition, the maximum decomposition temperature shifted to a lower temperature, which indicates enhanced ignition characteristics. This is the first time reporting on the synthesis and characterization of tertiary nanothermites based on nano-aluminum, potassium perchlorate, and carbon nanosize materials. It can be concluded that these novel nanothermite compositions exhibit dramatically improved properties as demonstrated by a 200 % increase in the heat of combustion with only a 5 % addition of graphene oxide. Moreover, the ignition temperature decreased from 545.1°C to 508.7°C enhancing the overall combustion characteristics.

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