Radiotherapy can induce the infiltration of immune suppressive cells which are involved in promoting tumor progression and recurrence. A number of natural products with immunomodulating abilities have been gaining attention as complementary cancer treatments. This attention is partly due to therapeutic strategies which have proven to be ineffective as a result of tumor-induced immunosuppressive cells found in the tumor microenvironment. The present study investigated whether HS-1793, a resveratrol analogue, can enhance the antitumor effects by inhibiting lymphocyte damage and immune suppression by regulatory T cells (Tregs) and tumor-associated macrophages (TAMs), during radiation therapy. FM3A cells were used to determine the role of HS-1793 in the radiation-induced tumor immunity of murine breast cancer. HS-1793 treatment with radiation significantly increased lymphocyte proliferation with concanavalin A (Con A) stimulation and reduced the DNA damage of lymphocytes in irradiated tumor-bearing mice. The administration of HS-1793 also decreased the number of Tregs, and reduced interleukin (IL)-10 and transforming growth factor (TGF)-β secretion in irradiated tumor-bearing mice. In addition, HS-1793 treatment inhibited CD206 + TAM infiltration in tumor tissue when compared to the controls or irradiation alone. Mechanistically, HS-1793 suppressed tumor growth via the activation of effector T cells in irradiated mice. On the whole, the findings of the present study reveal that HS-1793 treatment improves the outcome of radiation therapy by enhancing antitumor immunity. Indeed, HS-1793 appears to be a good therapeutic candidate for use in combination with radiotherapy in breast cancer.

The Cs-137 irradiator is widely used to irradiate biological samples for radiobiological research. To obtain the accurate outcomes, correct measurements of the delivered absorbed dose to a sample is important. The IAEA protocols such as TRS-277 and TRS-398 were recommended for the Cs-137 reference dosimetry. However in TRS-398 protocol, currently known as the most practical dosimetry protocol, the quality factor (   ) for Cs-137 gamma rays is not suggested. Therefore, the use of TRS-398 protocol is currently unavailable for the Cs-137 dosimetry directly. The calculation method previously introduced for high energy photon beams in radiotherapy was used for deriving the Cs-137 beam qualities (   ) for the 15 commercially available farmer type ionization chambers in this study. In conclusion,    values were ranged from 0.998 to 1.002 for Cs-137 gamma rays.These results can be used as the reference and dosimeter calibrations for Cs-137 gamma rays in the future radiobiological researches.

No abstract

This study was intended toward the evaluation of the correlation between the quenching coefficients and the counting efficiency for the physical quenching phenomenon and the effects of the properties of the standard sources for quenching on the tritium radioactivity concentration in the process of analyzing the tritium radioactivity concentration. Accordingly, a series of standard sources for quenching was prepared using three types of vials with different properties used for correction by the quenching phenomenon; the calculated values of the counting efficiency of a series of standard sources for quenching, relative errors in the counting values, uncertainty, and properties of the quenching correction curve were evaluated. On the basis of the results, nine samples (three glass-vial-type samples, three plastic-vial-type samples, and three Teflon-vial-type samples) were obtained and evaluated by applying Parameter Groups 1, 2, and 3, for which the efficiency was calibrated using the WinQ program in accordance with the properties of a series of standard sources for quenching. The results of this study are expected to serve as an aid in accurately understanding the standard sources for quenching, counting, and analyzing environmental samples that are subject to counting and analysis. K: Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators); Liquid detectors 1Corresponding author.