Nitric Oxide Is Involved in Heavy Ion-Induced Non-Targeted Effects in Human Fibroblasts

Previously, we investigated the dose response for chromosomal aberration (CA) for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) particles, and showed that the dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Our results suggested that the simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. Nitric oxide (NO) has been reported as a candidate for intercellular signaling for NTE in many studies. In order to estimate the contribution of NTE components in induced CA, we measured CA with and without an NO scavenger in normal skin fibroblasts cells after exposure to 600 MeV/u and 1 GeV/u 56Fe ions, less than one direct particle traversal per cell nucleus. Yields of CA were significantly lower in fibroblasts exposed to the NO scavenger compared to controls, suggesting involvement of NO in cell signaling for induction of CA. Media transferred from irradiated cells induced CA in non-irradiated cells, and this effect was abrogated with NO scavengers. Our results strongly support the importance of NTE contributions in the formation of CA at low-particle fluence in fibroblasts. View Full-Tex

Race and Ethnic Group Dependent Space Radiation Cancer Risk Predictions

Future space missions by national space agencies and private industry, including space tourism, will include a diverse makeup of crewmembers with extensive variability in age, sex, and race or ethnic groups. The relative risk (RR) model is used to transfer epidemiology data between populations to estimate radiation risks. In the RR model cancer risk is assumed to be proportional to background cancer rates and limited by other causes of death, which are dependent on genetic, environmental and dietary factors that are population dependent. Here we apply the NSCR-2020 model to make the first predictions of age dependent space radiation cancer risks for several U.S. populations, which includes Asian-Pacific Islanders (API), Black, Hispanic (white and black), and White (non-Hispanic) populations. Results suggest that male API and Hispanic populations have the overall lowest cancer risks, while White females have the highest risk. Blacks have similar total cancer rates than Whites, however their reduced life expectancy leads to modestly lower lifetime radiation risks compared to Whites. There are diverse tissue specific cancer risk ranking across sex and race, which include sex specific organ risks, female’s having larger lung, stomach, and urinary-bladder radiation risks, and male’s having larger colon and brain risks

Radiation Matters of the Heart: A Mini Review

Radiation Therapy (RT) has been critical in cancer treatment regimens to date. However, it has been shown that ionizing radiation is also associated with increased risk of damage to healthy tissues. At high radiation doses, varied effects including inactivation of cells in treated tissue and associated functional impairment are seen. These range from direct damage to the heart; particularly, diffuse fibrosis of the pericardium and myocardium, adhesion of the pericardium, injury to the blood vessels and stenosis. Cardiac damage is mostly a late responding end-point, occurring anywhere between 1 and 10 years after radiation procedures. Cardiovascular disease following radiotherapy was more common with radiation treatments used before the late 1980s. Modern RT regimens with more focused radiation beams, allow tumors to be targeted more precisely and shield the heart and other healthy tissues for minimizing the radiation damage to normal cells. In this review, we discuss radiation therapeutic doses used and post-radiation damage to the heart muscle from published studies. We also emphasize the need for early detection of cardiotoxicity and the need for more cardio-protection approaches where feasible

The Pathway from Radiation to Fibrosis: LET Dependence

It is well-known that Radiation-induced fibrosis (RIF) is a late event occurring months to years after the initial radiation exposure. Fibrotic lesions have been shown to manifest in many tissues including the skin, heart, lung, liver and kidney. Fibrosis occurs due to abnormal accumulation of extracellular matrix (ECM) proteins that result in loss of normal tissue and organ function. The cell type involved in RIF is myofibroblasts, which do not undergo apoptosis after healing but instead continue to accumulate, producing excessive amounts of ECM proteins, thereby damaging the tissues and organs. Reactive oxygen species, generated in response to radiation, is one signal that helps maintain the myofibroblast phenotype. In this review, we discuss molecular mechanisms leading to this late radiation event, known biomarkers for prediction, preclinical animal models of radiation-induced toxicity and current clinical trials designed for mitigation and treatment of radiation-induced fibrosis. We also discuss other physical properties such as linear energy transfer (LET) than the ones used in the clinics today which may have the potential to change our understanding on this inevitable pathway from radiation treatment to organ fibrosis.</jats:p

Race and Ethnic Group Dependent Space Radiation Cancer Risk Predictions

AbstractFuture space missions by national space agencies and private industry, including space tourism, will include a diverse makeup of crewmembers with extensive variability in age, sex, and race or ethnic groups. The relative risk (RR) model is used to transfer epidemiology data between populations to estimate radiation risks. In the RR model cancer risk is assumed to be proportional to background cancer rates and limited by other causes of death, which are dependent on genetic, environmental and dietary factors that are population dependent. Here we apply the NSCR-2020 model to make the first predictions of age dependent space radiation cancer risks for several U.S. populations, which includes Asian-Pacific Islanders (API), Black, Hispanic (white and black), and White (non-Hispanic) populations. Results suggest that male API and Hispanic populations have the overall lowest cancer risks, while White females have the highest risk. Blacks have similar total cancer rates as Whites, however their reduced life expectancy leads to modestly lower lifetime radiation risks compared to Whites. There are diverse tissue specific cancer risk ranking across sex and race, which include sex specific organ risks, females having larger lung, stomach, and urinary-bladder radiation risks, and males having larger colon and brain risks.</jats:p

Race and Ethnic Group Dependent Space Radiation Cancer Risk Predictions

Abstract Future space missions by national space agencies and private industry, including space tourism, will include a diverse makeup of crewmembers with extensive variability in age, sex, and race or ethnic groups. The relative risk (RR) model is used to transfer epidemiology data between populations to estimate radiation risks. In the RR model cancer risk is assumed to be proportional to background cancer rates and limited by other causes of death, which are dependent on genetic, environmental and dietary factors that are population dependent. Here we apply the NSCR-2020 model to make the first predictions of age dependent space radiation cancer risks for several U.S. populations, which includes Asian-Pacific Islanders (API), Black, Hispanic (white and black), and White (non-Hispanic) populations. Results suggest that male API and Hispanic populations have the overall lowest cancer risks, while White females have the highest risk. Blacks have similar total cancer rates than Whites, however their reduced life expectancy leads to modestly lower lifetime radiation risks compared to Whites. There are diverse tissue specific cancer risk ranking across sex and race, which include sex specific organ risks, female’s having larger lung, stomach, and urinary-bladder radiation risks, and male’s having larger colon and brain risks.</jats:p

Robot control from sequential image planes of a 3D object

Movement of a robot head between desired points in a 3D volume from (x1,y1,z1) to (x2,y2,z2) is crucial for high accuracy. When the knowledge of a 3D volume is only partial, obtained as a data set of cross-sectional image planes, control parameters for movement of the robot head are critical for best accuracy. In the present approach an attempt is being made to develop an interface for transforming control parameters of a robot system for desired movements of the robot head in the 3D volume from a sequence of cross-sectional image planes. Coordinates of a desired location from image data are obtained, and their corresponding locations on the object are estimated. These coordinates are transformed through matrix transformation into control parameters for the desired movements of the robot system. Most diagnostic medical imaging modalities obtain cross-sectional image planes of vital human organs. Treatment procedures often require 3D volume considerations. In the present approach a hypothetical radiation treatment procedure for a prostate cancer tumor in a 3D volume from given 2D cross-sectional sequential image planes is presented. Diagnostic ultrasound images of the prostate are obtained as sequential cross-sectional image planes at 2 mm apart from base to apex of the gland. An approach for robot coordinate movements for a simple robotic system with five degrees of freedom (Eshed Robotics, ER VII) is presented

Race and ethnic group dependent space radiation cancer risk predictions

AbstractFuture space missions by national space agencies and private industry, including space tourism, will include a diverse makeup of crewmembers with extensive variability in age, sex, and race or ethnic groups. The relative risk (RR) model is used to transfer epidemiology data between populations to estimate radiation risks. In the RR model cancer risk is assumed to be proportional to background cancer rates and limited by other causes of death, which are dependent on genetic, environmental and dietary factors that are population dependent. Here we apply the NSCR-2020 model to make the first predictions of age dependent space radiation cancer risks for several U.S. populations, which includes Asian-Pacific Islanders (API), Black, Hispanic (white and black), and White (non-Hispanic) populations. Results suggest that male API and Hispanic populations have the overall lowest cancer risks, while White females have the highest risk. Blacks have similar total cancer rates than Whites, however their reduced life expectancy leads to modestly lower lifetime radiation risks compared to Whites. There are diverse tissue specific cancer risk ranking across sex and race, which include sex specific organ risks, female’s having larger lung, stomach, and urinary-bladder radiation risks, and male’s having larger colon and brain risks.</jats:p