objective: radiation effects induced in non-irradiated cells are termed radiation-induced bystander effects (ribe). the present study intends to examine the ribe response of qu-db bystander cells to first, second and third radiation fractions and compare their cumulative outcome with an equal, single acute dose. materials and methods: this experimental study irradiated three groups of target ce...

Introduction: Radiation effects induced in non-irradiated cells are termed radiation- induced bystander effects (RIBE). The present study intends to examine the RIBE response of QU-DB bystander cells to first, second and third radiation fractions and compare their cumulative outcome with an equal, single acute dose.   Materials and Methods: This experimental ...

Interaction between radiation and Adriamycin damage reduced the width of the shoulder of the X-ray survival curve. This effect was found to persist for at least 24 hr after Adriamycin treatment. Adriamycin did not affect radiation damage when cells were treated either before two-dose fractionation or with the drug present between X-ray exposures. Adriamycin is unique in that its major effect on...

background: the exposure of cell lines to low-dose irradiation leads to changes at molecular level, which may induce adaptive response. we examined radio-adaptive doses effect on human colorectal adenocarcinoma cell line (ht29) and human fetal fibroblasts (mrc5) cell line followed by hyper and hypo fractionation regimes, with main purpose to decrease cell viability in ht29, and at the same time...

Background: The exposure of cell lines to low-dose irradiation leads to changes at molecular level, which may induce adaptive response. We examined radio-adaptive doses effect on human colorectal adenocarcinoma cell line (HT29) and human fetal fibroblasts (MRC5) cell line followed by hyper and hypo fractionation regimes, with main purpose to decrease cell viability in HT29, and at the same time...

Historically it has been shown repeatedly that single high doses of radiation do not allow a therapeutic differential between tumor and critical normal tissues but dose fractionation does. The purpose of conventional dose fractionation is to increase dose to the tumor while preserving normal tissue function. Tumors are generally irradiated with 2Gy dose per fraction delivered daily to a more or...

CTFFIND is a widely-used program for the estimation of objective lens defocus parameters from transmission electron micrographs. Defocus parameters are estimated by fitting a model of the microscope's contrast transfer function (CTF) to an image's amplitude spectrum. Here we describe modifications to the algorithm which make it significantly faster and more suitable for use with images collecte...

Accuracy of the radiotherapy requires some routine quality control and dosimetry calculations, which would be done by radiotherapy physicists. Due to the increasing use of computers and simulation software in medical science, as well as trends indicating its continued growth, this study aims to develop a new smart-phone application to perform common radiotherapy-related calculations. Computatio...