Ultrasound imaging classifications of thyroid nodules for malignancy risk stratification and clinical management : state of the art

Assessing the risk of malignancy in the thyroid with ultrasound (US) is crucial in patients with nodules, as it can aid in selecting those who should have a fine-needle aspiration (FNA) biopsy performed. Many studies have examined whether the US characteristics of thyroid nodules are useful indicators of histological malignancy. Overall, these investigations have identified a few US features that are significantly more frequent in malignant thyroid nodules which can be coalesced into a defining set to be used as an indicator of a higher risk of malignancy. Despite these efforts, none of these classifications have been widely adopted worldwide, and there are still conflicting recommendations from different institutions. Understanding the role and appropriate utilization of these systems could facilitate the effective interpretation and communication of thyroid US findings among referring physicians and radiologists. In this comprehensive review, we outline the major US classification systems of thyroid nodules published in the last few years

Thermoluminescent dosimeters (TLDs-100) calibration for dose verification in photon and proton radiation therapy

Thermoluminescent dosimeters (TLDs) are practical, accurate, and precise tools for point dosimetry in medical physics applications. TLDs are nowadays extensively used to measure dose in conformal radiation therapy in order to guarantee the safety of the treatment. Several national and international organizations recommend checking the effective dose delivered to an individual patient by means of in vivo dosimetry. Modern radiotherapy techniques employing both photon and ion beams exhibit excellent target conformation throught high steep-dose gradients between tumour and adjacent organs and tissues. In this context, catching potential dose errors and uncertainties in treatment delivering is the first step to ensure the optimization of the treatment plan. This study shows the results of the characterization of TLDs-100 at two Italian facilities devoted to advanced radiation treatments with photon and proton therapy. The individual sensitivity factor was determined, and the calibration curves were carried out in the dose range 0–20 Gy. By the analysis of the dose response curves, the linear region was identified under the dose level of 10 Gy. Characterization of the TLDs-100 has enabled their use for in vivo dosimetry especially in the dose range corresponding to the linear region of the dose response curves

Cohesin promotes the repair of ionizing radiation-induced DNA double-strand breaks in replicated chromatin.

The cohesin protein complex holds sister chromatids together after synthesis until mitosis. It also contributes to post-replicative DNA repair in yeast and higher eukaryotes and accumulates at sites of laser-induced damage in human cells. Our goal was to determine whether the cohesin subunits SMC1 and Rad21 contribute to DNA double-strand break repair in X-irradiated human cells in the G2 phase of the cell cycle. RNA interference-mediated depletion of SMC1 sensitized HeLa cells to X-rays. Repair of radiation-induced DNA double-strand breaks, measured by gammaH2AX/53BP1 foci analysis, was slower in SMC1- or Rad21-depleted cells than in controls in G2 but not in G1. Inhibition of the DNA damage kinase DNA-PK, but not ATM, further inhibited foci loss in cohesin-depleted cells in G2. SMC1 depletion had no effect on DNA single-strand break repair in either G1 or late S/G2. Rad21 and SMC1 were recruited to sites of X-ray-induced DNA damage in G2-phase cells, but not in G1, and only when DNA damage was concentrated in subnuclear stripes, generated by partially shielded ultrasoft X-rays. Our results suggest that the cohesin complex contributes to cell survival by promoting the repair of radiation-induced DNA double-strand breaks in G2-phase cells in an ATM-dependent pathway