ABSTRACT
BACKGROUND: The purpose of this study was to estimate the doses delivered to adult patients during chest examination for comparison with those elsewhere and to establish a local diagnostic reference level for the chest. The doses delivered in the standard X-ray examinations are not sufficiently optimized and controlled. The working protocols for the same exam given differ for similar morphotypes within the same hospital structure. MATERIALS AND METHODS: The entrance skin dose (mGy) of the chest was evaluated on 105 adult patients with a mass of 70 ± 10 kg in accordance with the 75th percentile of the irradiation parameters. The analysis and processing of the data was carried out by Excel 2010. The entrance skin dose of the chest obtained in mGy was 0.18 ± 0.21 for the PA incidence. CONCLUSION: The present study allowed us to observe large variations at the entrance skin doses of the chest. These variations have made it possible to understand that the entrance skin doses to the chest are optimized and do not exceed the proportions of those estimated by others and standards internationally. This aspect demonstrates that the diagnostic reference levels as enumerated are dependent on the doses delivered and include not only the notions of quality of the radiographic image and the quality assurance of the radiological equipments but also the level of the manipulators trained.
ABSTRACT
Mesenchymal stromal cells (MSCs) are adult multipotent stem cells residing as pericytes in various tissues and organs where they can differentiate into specialized cells to replace dying cells and damaged tissues. These cells are commonly found at injury sites and in tumors that are known to behave like " wounds that do not heal." In this article, we discuss the mechanisms of MSCs in migrating, homing, and repairing injured tissues. We also review a number of reports showing that tumor microenvironment triggers plasticity mechanisms in MSCs to induce malignant neoplastic tissue formation, maintenance, and chemoresistance, as well as tumor growth. The antitumor properties and therapeutic potential of MSCs are also discussed.
ABSTRACT
Breast cancer is the most frequent female malignancy worldwide. Current strategies in breast cancer therapy, including classical chemotherapy, hormone therapy, and targeted therapies, are usually associated with chemoresistance and serious adverse effects. Advances in our understanding of changes affecting the interactome in advanced and chemoresistant breast tumors have provided novel therapeutic targets, including, cyclin dependent kinases, mammalian target of rapamycin, Notch, Wnt and Shh. Inhibitors of these molecules recently entered clinical trials in mono- and combination therapy in metastatic and chemo-resistant breast cancers. Anticancer epigenetic drugs, mainly histone deacetylase inhibitors and DNA methyltransferase inhibitors, also entered clinical trials. Because of the complexity and heterogeneity of breast cancer, the future in therapy lies in the application of individualized tailored regimens. Emerging therapeutic targets and the implications for personalized-based therapy development in breast cancer are herein discussed.
