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Background and purpose: Binding a monoclonal antibody to tumor associated antigens is an effective method for cancer therapy because these agents can specifically target malignant cells. In fact, monoclonal antibodies are effective agents for diagnosis, grading and treatment of different kinds of cancers. In this research, a new monoclonal antibody against colon cancer cells was prepared and radiolabeling with technetium-99m evaluated.
Materials and Methods: This research was done in three parts: preparation of hybridoma cell against colon cancer cell line (HT29), production of monoclonal antibody, determination of its characterizations and radiolabeling with technetium-99m.
Results: mAb-D2 is an IgG1 with affinity constant of 7.2 × 109M-1 which can recognize CEA in tumor cells. Radiolabeling showed that 99mTc-HYNIC-mAb-D2 complex is stable, immunoradioactive, and has a desirable biodistribution.
Conclusion: In this study, we gained a new radiopharmaceutical that may be a good candidate for radioimmunoscintigraphy.

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Background and purpose: Imaging which is used in nuclear medicine is done using emit gamma rays whereas therapy in nuclear medicine is performed by applying radionuclide’s which emit beta radiation. Using Bremsstrahlung is a new field which is recently introduced in imaging. In the Bremsstrahlung imaging, collimator design should not be based on energy peak and whole energy spectrum should be considered. The main problem of these radiations is collimator penetration. This study suggests a new design for collimator in Bremsstrahlung imaging which weighs less than half of usual collimators. This design will somewhat influence the resolution and sensitivity. Furthermore, the effect of wiener filter in Bremsstrahlung imaging is also considered Material and Methods: Layer collimator in forms of digital phantom was designed by GATE simulator and its sensitivity and resolution in deferent layers was evaluated. Results: By increasing collimator layers, sensitivity rose by 9%, in contrast, due to penetration resolution decreased to 11%. Furthermore, we did not find any evidence that showed wiener filter in Bremsstrahlung imaging improved resolution. Conclusion: In this study, layer collimator has increased the sensitivity, consequently, the time required for collecting count for Bremsstrahlung imaging has decreased.

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Multiple myeloma is a monoclonal malignant proliferation of plasma cells that causes osteolytic lesions in the vertebrae, ribs, pelvic bone, skull and jaw. We report a case of a 66 year-old-woman with pain and right facial swelling. Radiographic examination showed a well-defined radiolucent lesion in left posterior mandible. An incisional biopsy was performed and histopathological examination revealed proliferation of malignant plasma cell with off-center and hyper chrome nucleus. The results of biopsy, imaging, and laboratory investigations led to the diagnosis of multiple myeloma. This maxillofacial manifestation of multiple myeloma is not that rare, but dentist knowledge about maxillofacial manifestation can help in early diagnosis and consequently better prognosis of the disease.

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Background and purpose: Simultaneous exposure of nanoparticles can cause serious damage to aquatic organisms including fish. The aim of this study was to investigate the toxicity effect of subchronic exposure of copper oxide nanoparticles (CuO NPs) in presence of titanium dioxide nanoparticles (TiO₂ NPs) on the histopathology of gill and kidney tissues of fish model in vivo exposure.

Materials and methods: In this study, one non-lethal concentration of TiO₂ NPs, two non-lethal concentrations of CuO NPs, two concentrations of TiO₂ NPs and CuO NPs mixture, and a control group (no chemicals) were used. After 10 days of exposure to these materials, samples of gill and kidney tissues were collected. In order to study classical histology the samples were prepared by hematoxylin-eosin staining and the slides were photographed by optical microscopy.

Results: The damages caused in gill were as following: secondary curved blades, increased mucus secretion, increase in the agglomeration of secondary lamellae, and aneurism and hyperplasia. Also, blood vessels dilation, vacuoles, necrosis, focal tubule degeneration, and increase in melano-macrophage were observed in kidney tissue of common carp.

Conclusion: The study suggested that toxic effects of CuO NPs on tissues of common carp in the joint presence of TiO₂ NPs were synergistic.