PURPOSE To characterize the radiation-enhancing effects and underlying mechanisms of combined treatment with celecoxib, a cyclooxygenase-2 selective inhibitor, and gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, in human lung cancer cells. EXPERIMENTAL DESIGN Clonogenic cytotoxicity assays and clonogenic radiation survival assays after treatments with celecoxi...

BACKGROUND Multidetector computed tomography has been proposed as a tool for routine screening for coronary artery calcification in asymptomatic individuals. As proposed, such screening could involve tens of millions of individuals, but detailed estimates of radiation doses and potential risk of radiation-induced cancer are not currently available. We estimated organ-specific radiation doses an...

INTRODUCTION The use of satellite techniques provides valuable information for mapping ash hazards, as well as the means to study and predict the fates of volcanic clouds. We have used ultraviolet (TOMS – Total Ozone Mapping Spectrometer) and infrared (e.g., AVHRR – Advanced Very High Resolution Radiometer; HIRS2 – High Resolution Infrared Radiation Sounder/2; GOES – Geostationary Operational E...

Background: Radiation therapy  uses high-energy radiation to kill cancer cells. Photoneutron contamination and induced radioactivity of high energy therapeutic photon beams are considered as the main source of occupational exposure to radiation therapists who works with linear accelerators operating above 10 MV. Materials and Methods: The gamma dose rates were measured after termination of...

Head and neck cancer is treated mainly by surgery and radiotherapy. Normal tissue toxicity due to x-ray exposure is a limiting factor for treatment success. Many efforts have been employed to develop predictive tests applied to clinical practice. Determination of lymphocyte radio-sensitivity by radio-induced apoptosis arises as a possible method to predict tissue toxicity due to radiotherapy. T...

PURPOSE This study examined the status of radiation-induced liver injury in adjuvant or palliative gastric cancer radiation therapy (RT), identified risk factors of radiation-induced liver injury in gastric cancer RT, analysed the dose-volume effects of liver injury, and developed a liver dose limitation reference for gastric cancer RT. METHODS AND MATERIALS Data for 56 post-operative gastric...

Radiotherapy is the major form of treatment for many human cancer. During the course of treatment, the ionising radiation produces many biological effects not only in cancer but also in normal cells. Due to the risk of toxicity to normal cells, the radioprotectors are needed to reduce the normal tissue injury during the irradiation of tumours without influence on effectiveness on cancer treatme...

The phosphatidylinositol 3-kinase (PI3K)/Akt pathway is known to be activated by radiation. The mammalian target of rapamycin (mTOR) is downstream of Akt, and we investigated the effects of radiation on Akt/mTOR signaling in breast cancer cell models. RAD001 (everolimus), a potent derivative of the mTOR inhibitor rapamycin, was used to study the effects of mTOR inhibition, as the role of mTOR i...

A number of methods for producing sub-picosecond beam microbunching have been developed in recent years. A train of these bunches is capable of generating THz radiation via multiple mechanisms like transition, Cherenkov and undulator radiation. We utilize a bunch train with tunable spacing to selectively excite high order TM0,n modes in a multimode structure. In this paper we present experiment...