Synchrotron microtomography to evaluate effects of different polychemotherapy drugs on cortical bone structure.

PURPOSE: To determine the effects of different polychemotherapy drugs on cortical bone structure, the femur diaphysis of rats were treated with two different chemotherapy drugs, AC (doxorubicin + cyclophosphamide) and TC (docetaxel + cyclophosphamide), and evaluated by 3D morphological analysis using synchrotron radiation microtomography. MATERIALS AND METHODS: Wistar rats were classified into three groups. One group received doses of docetaxel and cyclophosphamide (G1) - TC regimen; a second group received doses of doxorubicin and cyclophosphamide (G2) - AC regimen; while a control group (G0) received no further treatment. 3D tomographic images of the rats' femurs were obtained at the SYRMEP (Synchrotron Radiation for Medical Physics) beamline at the ELETTRA Synchrotron Laboratory in Trieste, Italy, using monochromatic X-rays with resolution of 9 µm. RESULTS: It could be shown that the treatment caused significant differences in morphological parameters measured from the 3D images of femur diaphysis of rats, among the studied groups, complementing a previous study using stereological methods, biochemistry and electron microscopy. CONCLUSIONS: Our results indicate that the same process of osteoporosis caused by advancing age might occur in young women treated with docetaxel + cyclophosphamide (TC) and doxorubicin + cyclophosphamide (AC). 3D microtomography was shown to be an outstanding technique for bone analysis.

Evaluation of rib microstructure in Wistar rats using SR-µCT after radiation therapy simulation for breast cancer.

A better understanding of biological interactions that occur after exposure to photon radiation is needed in order to optimize therapeutic regimens and facilitate development and strategies that decrease radiation-induced side effects in humans. In this work, ribs of Wistar rat submitted to radiotherapy simulation were imaged using synchrotron radiation computed microtomography at Elettra Synchrotron Laboratory in Trieste, Italy. Histomorphometric parameters were calculated directly from the 3D microtomographic images and showed significant differences between irradiated and non-irradiated groups.

Segmentation of synchrotron radiation micro-computed tomography images using energy minimization via graph cuts.

The research on applications of segmentation algorithms to Synchrotron Radiation X-Ray micro-Computed Tomography (SR-µCT) is an open problem, due to the interesting and well-known characteristics of SR images, such as the phase contrast effect. The Energy Minimization via Graph Cuts (EMvGC) algorithm represents state-of-art segmentation algorithm, presenting an enormous potential of application in SR-µCT imaging. We describe the application of the algorithm EMvGC with swap move for the segmentation of bone images acquired at the ELETTRA Laboratory (Trieste, Italy).

Phase contrast X-ray synchrotron imaging for assessing external and internal morphology of Rhodnius prolixus.

PhC-SR-µCT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions. This technique is performed in blood sucker, Rhodnius prolixus--one of the most important insect vectors of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America--was able to provide excellent information about the microanatomy of the thorax and head allowing a new tool for further studies of development and physiology of triatomine by a non-invasive method of observation.