A new approach to reduce uncertainties in space radiation cancer risk predictions.

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Francis A Cucinotta

Full Text Available The prediction of space radiation induced cancer risk carries large uncertainties with two of the largest uncertainties being radiation quality and dose-rate effects. In risk models the ratio of the quality factor (QF to the dose and dose-rate reduction effectiveness factor (DDREF parameter is used to scale organ doses for cosmic ray proton and high charge and energy (HZE particles to a hazard rate for γ-rays derived from human epidemiology data. In previous work, particle track structure concepts were used to formulate a space radiation QF function that is dependent on particle charge number Z, and kinetic energy per atomic mass unit, E. QF uncertainties where represented by subjective probability distribution functions (PDF for the three QF parameters that described its maximum value and shape parameters for Z and E dependences. Here I report on an analysis of a maximum QF parameter and its uncertainty using mouse tumor induction data. Because experimental data for risks at low doses of γ-rays are highly uncertain which impacts estimates of maximum values of relative biological effectiveness (RBEmax, I developed an alternate QF model, denoted QFγAcute where QFs are defined relative to higher acute γ-ray doses (0.5 to 3 Gy. The alternate model reduces the dependence of risk projections on the DDREF, however a DDREF is still needed for risk estimates for high-energy protons and other primary or secondary sparsely ionizing space radiation components. Risk projections (upper confidence levels (CL for space missions show a reduction of about 40% (CL∼50% using the QFγAcute model compared the QFs based on RBEmax and about 25% (CL∼35% compared to previous estimates. In addition, I discuss how a possible qualitative difference leading to increased tumor lethality for HZE particles compared to low LET radiation and background tumors remains a large uncertainty in risk estimates.

Diagnosis of acute radiation disease by Enzyme Immune-Assay (EIA)

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Popov, D.; Maliev, V.; Jones, J.; Gonta, S.; Prasad, K.; Rachal, C.

2006-01-01

Diagnosis of the acute radiation disease by the method of immune enzyme assay is a simple and efficient tool of evaluating and biological dosimetry and forecasting of development of the acute radiation defeats as at group of population so at individuals locating in the zone polluted by the radiation. We use as biological markers the group of essential radiotoxins - high molecular mass glycoprotein ( molecular mass - 200 - 250 kDa ) - radiation antigens (S.D.R. - specific radiation determinant ) accumulated in the lymphoid system, with epitopes specific to each form of radiation syndrome, after animals have been irradiated in doses inducing the development of the cerebral (1), toxic ( 2), gastrointestinal ( 3 ) and typical ( 4 ) forms of acute radiation sickness. These two phenomena allowed us to develop a technologies for diagnosis, prophylaxis and therapy of radiation disease - enzyme immune assay ( EIA ), anti radiation vaccine, anti radiation serum, method of immune - lymph - plasma-sorption. The important first step in effectiveness of therapy is an accurate assessment of severity of disease in early period after irradiation. The ideal markers for early and accurate assessment is high weight glycoprotein with specifics radiation induced features (S.D.R.) mentioned above. This biology active substance isolated from lymph can induct the symptoms of radiation syndrome without previously radiation when it is administrated intra-muscularly or intravenously to healthy animals. Enzyme immune assay (EIA) allowed researchers to indicate the significant levels of different forms of S.D.R. in peripheral blood of animals in first 24 hours after radiation. Indication of high level of S.D.R. -1 allowed to forecast a fast development of cerebral form of acute radiation disease. Determination of high levels of S.D.R.-2, S.D.R.-3 and S.D.R.-4 in peripheral blood allowed to recognize early periods of toxic, gastrointestinal and typical forms of acute radiation sickness

Diagnosis of acute radiation disease by Enzyme Immune-Assay (EIA)

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Popov, D.; Maliev, V. [Russian Academy of Science, Vladicaukas (Russian Federation); Jones, J.; Gonta, S. [NASA -Johnson Spa ce Center, Houston (United States); Prasad, K. [Antioxidant Research Institute, Premier Micrinutrient corporation, Novato (United States); Rachal, C. [Univercity Space Research Assotiation, Colorado (United States)

2006-07-01

Diagnosis of the acute radiation disease by the method of immune enzyme assay is a simple and efficient tool of evaluating and biological dosimetry and forecasting of development of the acute radiation defeats as at group of population so at individuals locating in the zone polluted by the radiation. We use as biological markers the group of essential radiotoxins - high molecular mass glycoprotein ( molecular mass - 200 - 250 kDa ) - radiation antigens (S.D.R. - specific radiation determinant ) accumulated in the lymphoid system, with epitopes specific to each form of radiation syndrome, after animals have been irradiated in doses inducing the development of the cerebral (1), toxic ( 2), gastrointestinal ( 3 ) and typical ( 4 ) forms of acute radiation sickness. These two phenomena allowed us to develop a technologies for diagnosis, prophylaxis and therapy of radiation disease - enzyme immune assay ( EIA ), anti radiation vaccine, anti radiation serum, method of immune - lymph - plasma-sorption. The important first step in effectiveness of therapy is an accurate assessment of severity of disease in early period after irradiation. The ideal markers for early and accurate assessment is high weight glycoprotein with specifics radiation induced features (S.D.R.) mentioned above. This biology active substance isolated from lymph can induct the symptoms of radiation syndrome without previously radiation when it is administrated intra-muscularly or intravenously to healthy animals. Enzyme immune assay (EIA) allowed researchers to indicate the significant levels of different forms of S.D.R. in peripheral blood of animals in first 24 hours after radiation. Indication of high level of S.D.R. -1 allowed to forecast a fast development of cerebral form of acute radiation disease. Determination of high levels of S.D.R.-2, S.D.R.-3 and S.D.R.-4 in peripheral blood allowed to recognize early periods of toxic, gastrointestinal and typical forms of acute radiation sickness

Probabilistic methodology for estimating radiation-induced cancer risk

International Nuclear Information System (INIS)

Dunning, D.E. Jr.; Leggett, R.W.; Williams, L.R.

1981-01-01

The RICRAC computer code was developed at Oak Ridge National Laboratory to provide a versatile and convenient methodology for radiation risk assessment. The code allows as input essentially any dose pattern commonly encountered in risk assessments for either acute or chronic exposures, and it includes consideration of the age structure of the exposed population. Results produced by the analysis include the probability of one or more radiation-induced cancer deaths in a specified population, expected numbers of deaths, and expected years of life lost as a result of premature fatalities. These calculatons include consideration of competing risks of death from all other causes. The program also generates a probability frequency distribution of the expected number of cancers in any specified cohort resulting from a given radiation dose. The methods may be applied to any specified population and dose scenario

Physical and biomedical countermeasures for space radiation risk

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Durante, Marco

2008-01-01

Radiation exposure represents a serious hindrance for long-term interplanetary missions because of the high uncertainty on risk coefficients, and to the lack of simple countermeasures. Even if uncertainties in risk assessment will he reduced in the next few years, there is little doubt that appropriate countermeasures have to be taken to reduce the exposure or the biological damage produced by cosmic radiation. In addition, it is necessary to provide effective countermeasures against solar particle events, which can produce acute effects, even life threatening, for inadequately protected crews. Strategies that may prove to he effective in reducing exposure, or the effects of the irradiation, include shielding, administration of drugs or dietary supplements to reduce the radiation effects, crew selection based on a screening of individual radiation sensitivity. It is foreseeable that research in passive and active radiation shielding, radioprotective chemicals, and individual susceptibility will boost in the next years to provide efficient countermeasures to the space radiation threat. (orig.)

Acute radiation proctitis. A clinical, histopathological and histochemical study

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Hovdenak, Nils

2004-01-01

The aim of the study is: 1) A sequential description of the clinical course of acute radiation proctitis during pelvic RT. 2) A sequential description of the rectal mucosal histopathology during pelvic RT as a possible substrate for clinical toxicity. 3) To assess the mucosal protease activity during RT as a possible explanation of the observed tissue changes. 4) To assess the efficacy of prophylactic sucralfate in acute radiation proctitis a randomised study was initiated and carried out together with a meta-analysis of previously available data. 5) Most studies on clinical acute toxicity in pelvic RT use either the RTOG/EORTC score system or focus on diarrhoea/stool frequency. A more differentiated and sensitive recording was developed and tested to pick up symptoms escaping the commonly used scores. 6) Study the relation between histopathological findings and the clinical picture. 4 papers presenting various studies are included. The titles are: 1) Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy. 2) Clinical significance of increased gelatinolytic activity in the rectal mucosa during external beam radiation therapy of prostate cancer. 3) Profiles and time course of acute radiation toxicity symptoms during conformal radiotherapy for cancer of the prostate. 4) Sucralfate does not ameliorate acute radiation proctitis. Some future prospects are discussed

Acute radiation proctitis. A clinical, histopathological and histochemical study

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Hovdenak, Nils

2004-07-01

The aim of the study is: 1) A sequential description of the clinical course of acute radiation proctitis during pelvic RT. 2) A sequential description of the rectal mucosal histopathology during pelvic RT as a possible substrate for clinical toxicity. 3) To assess the mucosal protease activity during RT as a possible explanation of the observed tissue changes. 4) To assess the efficacy of prophylactic sucralfate in acute radiation proctitis a randomised study was initiated and carried out together with a meta-analysis of previously available data. 5) Most studies on clinical acute toxicity in pelvic RT use either the RTOG/EORTC score system or focus on diarrhoea/stool frequency. A more differentiated and sensitive recording was developed and tested to pick up symptoms escaping the commonly used scores. 6) Study the relation between histopathological findings and the clinical picture. 4 papers presenting various studies are included. The titles are: 1) Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy. 2) Clinical significance of increased gelatinolytic activity in the rectal mucosa during external beam radiation therapy of prostate cancer. 3) Profiles and time course of acute radiation toxicity symptoms during conformal radiotherapy for cancer of the prostate. 4) Sucralfate does not ameliorate acute radiation proctitis. Some future prospects are discussed.

Lung pathology in case of acute radiation injury

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Vlasov, P.A.; Kvacheva, Yu.V.

1998-01-01

Results of pathomorphological studies of 27 patients exposed to total external γ- and β-radiation resulted from the Chernobyl accident and lost due to the acute radiation disease in the first weeks following radiation exposure are discussed. Dose range is 3.7-13.7 Gy. Two groups of pathological changes in lungs are revealed, those are: infection (bacterial, viral and fungous) ones caused by acute radiation disease and signs of respiratory distress-syndrome in adults [ru

New scoring system identifies kidney outcome with radiation therapy in acute renal allograft rejection

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Chen, Luci M.; Godinez, Juan; Thisted, Ronald A.; Woodle, E. Steve; Thistlewaite, J. Richard; Powers, Claire; Haraf, Daniel

2000-01-01

Purpose: To evaluate the role of radiation therapy for acute refractory renal rejection after failure of medical intervention, and to identify risk factors that influence graft survival following radiation therapy. Methods: Between June 1989 and December 1995, 53 renal transplant recipients (34 men and 19 women) were treated with localized radiation therapy for acute renal allograft rejection. Graft rejection was defined as an increase in serum creatinine with histologic evidence of rejection on renal biopsy. Ninety-one percent were cadaveric transplant recipients. The majority of patients who experienced acute graft rejection initially received corticosteroid therapy, except for 25% who were referred for radiation therapy and steroids for the first rejection. In more recent years, patients with moderate or severe steroid-resistant or recurrent rejection received OKT3, a polyclonal antilymphocyte antibody (ATGAM), tacrolimus (FK506), or mycophenolate mofetil (MMF). Patients who failed to respond to medical treatment were then referred for radiation therapy. Ultrasound was performed for kidney localization. Treatment consisted of a dose of 600 cGy given in 3 or 4 fractions using 6 MV photons, delivered AP or AP/PA. Results: The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year, and 36% at 5 years. The median follow-up from the date of transplant to the last follow-up was 22 months. The median time from the date of transplant to the initiation of radiotherapy was 3 months, and the median time from the initiation of radiotherapy to the last follow-up was 10 months. Variables evaluated were as follows: human leukocyte antigen matching on HLA-A, HLA-B, and HLA-DR, the transplant panel-reactive antibodies (PRA) at transplantation, number of acute rejection episodes, interval from the date of the transplant to the first rejection, serum creatinine levels at the time of the first radiation treatment, number of transplants, and

Considerations on the classification of acute radiation sickness

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Mikhajlov, M.A.; Andreev, E.

1975-01-01

Radiation disease is a well-defined and extensively studied entity with typical signs and symptomatology. A basic point in establishing a classification is dose absorbed by the organism. The pattern of pathology displayed will vary with dose distribution in time and space. Acute radiation disease after single, overall exposure to a radiation level ranging from 100 to 1000 rem and above may be manifested in four main forms, according to the prevailing pathogenetic mechanism: cerebral, toxemic, intestinal, and a typical form dominated by injury to the hematopoietic system. In the course of the disease, three major periods may be distinguished: development, recovery, and long-term effects and outcome. These three periods will not necessarily be represented in all forms of radiation disease. As for the clinical symptomatology of acute radiation disease, its evolution allows the delineation of four phases: primary general reactions, latent period, clinical manifestation, and apparent recovery. In a typical form of acute radiation disease, severity of effects is a function of dose. Chronic radiation disease may also be of two varieties, depending on space distribution of dose. In addition, a third variety has been distinguished, namely the case of a combination of external exposure with internal contamination. Similar to the acute radiation disease, periods and degrees of severity in chronic radiation disease will vary with cumulative radiation dose. In this case, degrees of severity overlap with phases in the development of the pathological process. A category by itself in the classification is alloted to combined lesions resulting from exposure to radiological plus nonradiological factors. (A.B.)

NASA Space Radiation Risk Project: Overview and Recent Results

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Blattnig, Steve R.; Chappell, Lori J.; George, Kerry A.; Hada, Megumi; Hu, Shaowen; Kidane, Yared H.; Kim, Myung-Hee Y.; Kovyrshina, Tatiana; Norman, Ryan B.; Nounu, Hatem N.;

Explanation of nurse standard of external exposure acute radiation sickness

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Lu Xiuling; Jiang Enhai; Sun Feifei; Zhang Bin; Wang Xiaoguang; Wang Guilin

2012-01-01

National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

Cerebrovascular Acute Radiation Syndrome : Radiation Neurotoxins, Mechanisms of Toxicity, Neuroimmune Interactions.

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Popov, Dmitri; Maliev, Slava

Introduction: Cerebrovascular Acute Radiation Syndrome (CvARS) is an extremely severe in-jury of Central Nervous System (CNS) and Peripheral Nervous System (PNS). CvARS can be induced by the high doses of neutron, heavy ions, or gamma radiation. The Syndrome clinical picture depends on a type, timing, and the doses of radiation. Four grades of the CvARS were defined: mild, moderate, severe, and extremely severe. Also, four stages of CvARS were developed: prodromal, latent, manifest, outcome -death. Duration of stages depends on the types, doses, and time of radiation. The CvARS clinical symptoms are: respiratory distress, hypotension, cerebral edema, severe disorder of cerebral blood microcirculation, and acute motor weakness. The radiation toxins, Cerebro-Vascular Radiation Neurotoxins (SvARSn), determine development of the acute radiation syndrome. Mechanism of action of the toxins: Though pathogenesis of radiation injury of CNS remains unknown, our concept describes the Cv ARS as a result of Neurotoxicity and Excitotoxicity, cell death through apoptotic necrosis. Neurotoxicity occurs after the high doses radiation exposure, formation of radiation neuro-toxins, possible bioradicals, or group of specific enzymes. Intracerebral hemorrhage can be a consequence of the damage of endothelial cells caused by radiation and the radiation tox-ins. Disruption of blood-brain barrier (BBB)and blood-cerebrospinal fluid barrier (BCFB)is possibly the most significant effect of microcirculation disorder and metabolic insufficiency. NMDA-receptors excitotoxic injury mediated by cerebral ischemia and cerebral hypoxia. Dam-age of the pyramidal cells in layers 3 and 5 and Purkinje cell layer the cerebral cortex , damage of pyramidal cells in the hippocampus occur as a result of cerebral ischemia and intracerebral bleeding. Methods: Radiation Toxins of CV ARS are defined as glycoproteins with the molec-ular weight of RT toxins ranges from 200-250 kDa and with high enzymatic activity

Hematopoietic Acute Radiation Syndrome (Bone marrow syndrome, Aplastic Anemia): Molecular Mechanisms of Radiation Toxicity.

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Popov, Dmitri

Key Words: Aplastic Anemia (AA), Pluripotential Stem Cells (PSC) Introduction: Aplastic Anemia (AA) is a disorder of the pluripotential stem cells involve a decrease in the number of cells of myeloid, erythroid and megakaryotic lineage [Segel et al. 2000 ]. The etiology of AA include idiopathic cases and secondary aplastic anemia after exposure to drugs, toxins, chemicals, viral infections, lympho-proliferative diseases, radiation, genetic causes, myelodisplastic syndromes and hypoplastic anemias, thymomas, lymphomas. [Brodskyet al. 2005.,Modan et al. 1975., Szklo et al. 1975]. Hematopoietic Acute Radiation Syndrome (or Bone marrow syndrome, or Radiation-Acquired Aplastic Anemia) is the acute toxic syndrome which usually occurs with a dose of irradiation between 0.7 and 10 Gy (70- 1000 rads), depending on the species irradiated. [Waselenko et al., 2004]. The etiology of bone morrow damage from high-level radiation exposure results depends on the radiosensitivity of certain bone marrow cell lines. [Waselenko et al. 2004] Aplastic anemia after radiation exposure is a clinical syndrome that results from a marked disorder of bone marrow blood cell production. [Waselenko et al. 2004] Radiation hematotoxicity is mediated via genotoxic and other specific toxic mechanisms, leading to aplasia, cell apoptosis or necrosis, initiation via genetic mechanisms of clonal disorders, in cases such as the acute radiation-acquired form of AA. AA results from radiation injury to pluripotential and multipotential stem cells in the bone marrow. The clinical signs displayed in reticulocytopenia, anemia, granulocytopenia, monocytopenia, and thrombocytopenia. The number of marrow CD34+ cells (multipotential hematopoietic progenitors) and their derivative colony-forming unit{granulocyte-macrophage (CFU-GM) and burst forming unit {erythroid (BFU{E) are reduced markedly in patients with AA. [Guinan 2011, Brodski et al. 2005, Beutler et al.,2000] Cells expressing CD34 (CD34+ cell) are normally

Review of the controversy on risks from low levels of radiation

International Nuclear Information System (INIS)

Higson, D.

2001-01-01

The need for regulation of low levels of radiation exposure, and the estimation of risks from such exposures, are based on the assumption that risk is proportional to dose without a threshold, the 'linear no-threshold (LNT) hypothesis'. This assumption is not supported by scientific data. There is no clear evidence of harm from low levels of exposure, up to at least 20 mSv (acute dose) or total dose rates of at least 50 mSv per year. Even allowing for reasonable extrapolation from radiation levels at which harmful effects have been observed, the LNT assumption should not be used to estimate risks from doses less than 100 mSv. Laboratory and epidemiological evidence, and evolutionary expectations of biological effects from low level radiation, suggest that beneficial health effects (sometimes called 'radiation hormesis') are at least as likely as harmful effects from such exposures. Controversy on this matter strikes at the basis of radiation protection practice

Effective chemotherapy of acute myelocytic leukemia occurring after alkylating agent or radiation therapy for prior malignancy

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Vaughan, W.P.; Karp, J.E.; Burke, P.J.

1983-01-01

Eleven consecutive patients with acute myelocytic leukemia occurring as a second malignancy were treated with high-dose, timed, sequential chemotherapy. Eight of the patients were felt to have ''secondary'' acute leukemia because they had received an alkylating agent or radiation therapy. The other three patients were considered controls. Despite a median age of 65, four of the eight secondary leukemia patients achieved complete remission with this regimen. One of the three control patients also achieved complete remission. This remission rate and duration are comparable to what was achieved with this treatment of ''primary'' acute myelocytic leukemia during the same period of time. These results suggest that patients with leukemia occurring after an alkylating agent or radiation therapy are not at especially high risk if treated aggressively

Risk factors for acute renal failure: inherent and modifiable risks.

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Leblanc, Martine; Kellum, John A; Gibney, R T Noel; Lieberthal, Wilfred; Tumlin, James; Mehta, Ravindra

2005-12-01

Our purpose is to discuss established risk factors in the development of acute renal failure and briefly overview clinical markers and preventive measures. Findings from the literature support the role of older age, diabetes, underlying renal insufficiency, and heart failure as predisposing factors for acute renal failure. Diabetics with baseline renal insufficiency represent the highest risk subgroup. An association between sepsis, hypovolemia, and acute renal failure is clear. Liver failure, rhabdomyolysis, and open-heart surgery (especially valve replacement) are clinical conditions potentially leading to acute renal failure. Increasing evidence shows that intraabdominal hypertension may contribute to the development of acute renal failure. Radiocontrast and antimicrobial agents are the most common causes of nephrotoxic acute renal failure. In terms of prevention, avoiding nephrotoxins when possible is certainly desirable; fluid therapy is an effective prevention measure in certain clinical circumstances. Supporting cardiac output, mean arterial pressure, and renal perfusion pressure are indicated to reduce the risk for acute renal failure. Nonionic, isoosmolar intravenous contrast should be used in high-risk patients. Although urine output and serum creatinine lack sensitivity and specificity in acute renal failure, they remain the most used parameters in clinical practice. There are identified risk factors of acute renal failure. Because acute renal failure is associated with a worsening outcome, particularly if occurring in critical illness and if severe enough to require renal replacement therapy, preventive measures should be part of appropriate management.

Oral sucralfate in acute radiation oesophagitis

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Sur, R.K. (Dept. of Radiotherapy, Postgraduate Inst. of Medical Education and Research, Chandigarh (India)); Kochhar, R. (Dept. of Gastroenterology, Postgraduate Inst. of Medical Education and Research, Chandigarh (India)); Singh, D.P. (Dept. of Radiotherapy, Postgraduate Inst. of Medical Education and Research, Chandigarh (India))

1994-01-01

Eighty patients with carcinoma in the middle third of oesophagus and with acute radiation oesophagitis following external beam and intracavitary radiotherapy were managed by two different schedules. Group 1 (n = 40) received an antacid containing sodium alginate whereas Group 2 (n = 40) were given a 10% sucralfate suspension during 4 weeks. In Group 2, 32 patients had significant relief of symptoms within 7 days of treatment and most ulcers had healed by 12 days of treatment as seen on endoscopy. Patients in Group 1, on the other hand, showed little improvement of symptoms and had persistent ulcers even after 4 weeks of therapy. We conclude that sucralfate is useful in the management of acute radiation oesophagitis. (orig.).

Oral sucralfate in acute radiation oesophagitis

International Nuclear Information System (INIS)

Sur, R.K.; Kochhar, R.; Singh, D.P.

1994-01-01

Eighty patients with carcinoma in the middle third of oesophagus and with acute radiation oesophagitis following external beam and intracavitary radiotherapy were managed by two different schedules. Group 1 (n = 40) received an antacid containing sodium alginate whereas Group 2 (n = 40) were given a 10% sucralfate suspension during 4 weeks. In Group 2, 32 patients had significant relief of symptoms within 7 days of treatment and most ulcers had healed by 12 days of treatment as seen on endoscopy. Patients in Group 1, on the other hand, showed little improvement of symptoms and had persistent ulcers even after 4 weeks of therapy. We conclude that sucralfate is useful in the management of acute radiation oesophagitis. (orig.)

On ionising radiation and breast cancer risk

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Mattson, Anders

1999-05-01

A cohort of 3,090 women with clinical diagnosis of benign breast disease (BBD) was studied. Of these, 1,216 were treated with radiation therapy during 1925-54 (median age 40 years). The mean dose to the breasts was 5.8 Gy (range 0-50 Gy). Among other organs the lung received the highest scattered dose (0.75 Gy; range 0.004-8.98 Gy) and the rectum the lowest (0.008 Gy; range 0-0.06 Gy). A pooled analysis of eight breast cancer incidence cohorts was done, including: tumour registry data on breast cancer incidence among women in the Life Span Study cohort of atomic bomb survivors; women in Massachusetts who received repeated chest fluoroscopic during lung collapse treatment for tuberculosis; women who received x-ray therapy for acute post-partum mastitis; women who were irradiated in infancy for enlarged thymus glands ; two Swedish cohorts of women who received radiation treatments during infancy for skin hemangioma; and the BBD cohort. Together the cohorts included almost 78,000 women (-35,000 were exposed), around 1.8 million woman-years and 1500 cases. The breast cancer incidence rate as a function of breast dose was analysed using linear-quadratic Poisson regression models. Cell-killing effects and other modifying effects were incorporated through additional log-linear terms. Additive (EAR) and multiplicative (ERR) models were compared in estimating the age-at-exposure patterns and time related excess. The carcinogenic risks associated with radiation in mammographic mass screening is evaluated. Assessment was made in terms of breast cancer mortality and years of life. Effects were related to rates not influenced by a mammographic mass screening program and based on a hypothetical cohort of 100,000 40-year old women with no history of breast cancer being followed to 100 years of age. Two radiation risk assumptions were compared. The dose-response relationship is linear with little support in data for an upward curvature at low to medium doses. The competing effect

On ionising radiation and breast cancer risk

International Nuclear Information System (INIS)

Mattson, Anders

1999-01-01

A cohort of 3,090 women with clinical diagnosis of benign breast disease (BBD) was studied. Of these, 1,216 were treated with radiation therapy during 1925-54 (median age 40 years). The mean dose to the breasts was 5.8 Gy (range 0-50 Gy). Among other organs the lung received the highest scattered dose (0.75 Gy; range 0.004-8.98 Gy) and the rectum the lowest (0.008 Gy; range 0-0.06 Gy). A pooled analysis of eight breast cancer incidence cohorts was done, including: tumour registry data on breast cancer incidence among women in the Life Span Study cohort of atomic bomb survivors; women in Massachusetts who received repeated chest fluoroscopic during lung collapse treatment for tuberculosis; women who received x-ray therapy for acute post-partum mastitis; women who were irradiated in infancy for enlarged thymus glands ; two Swedish cohorts of women who received radiation treatments during infancy for skin hemangioma; and the BBD) cohort. Together the cohorts included almost 78,000 women (-35,000 were exposed), around 1.8 million woman-years and 1500 cases. The breast cancer incidence rate as a function of breast dose was analysed using linear-quadratic Poisson regression models. Cell-killing effects and other modifying effects were incorporated through additional log-linear terms. Additive (EAR) and multiplicative (ERR) models were compared in estimating the age-at-exposure patterns and time related excess. The carcinogenic risks associated with radiation in mammographic mass screening is evaluated. Assessment was made in terms of breast cancer mortality and years of life. Effects were related to rates not influenced by a mammographic mass screening program and based on a hypothetical cohort of 100,000 40-year old women with no history of breast cancer being followed to 100 years of age. Two radiation risk assumptions were compared. The dose-response relationship is linear with little support in data for an upward curvature at low to medium doses. The competing effect

Radiation-induced acute myeloid leukaemia in mice

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Bouffler, S.D.; Silver, A.R.J.; Cox, R. [National Radiological Protection Board, Chilton (United Kingdom)

2000-07-01

Ample epidemiological studies of human populations implicate ionizing radiation as a carcinogen and these quantitative studies provide the foundation for the core estimates of radiation cancer risk. The majority of the epidemiological data originate from situations of radiation exposure at high dose and high dose rate. The relevance of risk estimates based on such exposures to the more commonly encountered low dose and dose rate situation has been questioned frequently. Thus, there is a need to investigate and quantitate low dose and dose rate effects. A number of approaches may be considered, for example, very large scale epidemiology, very large scale animal experimentation; however, both of these present problems of a practical and/or ethical nature. A further possible approach is that of mechanistic modelling. This requires a fairly detailed understanding of neoplastic disease and how it develops post-irradiation. Many factors and variables have to be taken into consideration in mechanistic modelling approaches. Testing of mechanistic modelling schemes is best carried out using animal model systems. Acute myeloid leukaemia (AML) is a radiogenic cancer of significance in man and several good mouse models of the disease are available. Here, recent studies conducted at NRPB with the aim of elucidating the post-irradiation development of AML will be discussed. In particular three areas critical for developing a sound mechanistic model will be covered, definition of the initiating event; study of disease progression, this addresses the question of the frequency of conversion of initiated cells into the neoplastic state and the influence of genetic background on leukaemogenesis. (author)

Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy

International Nuclear Information System (INIS)

Hess, Clayton B.; Thompson, Holly M.; Benedict, Stanley H.; Seibert, J. Anthony; Wong, Kenneth; Vaughan, Andrew T.; Chen, Allen M.

2016-01-01

Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning—a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of “gentle IGRT.”

Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy

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Hess, Clayton B. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Thompson, Holly M. [Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California (United States); Benedict, Stanley H. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Seibert, J. Anthony [Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California (United States); Wong, Kenneth [Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California (United States); Vaughan, Andrew T. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Chen, Allen M., E-mail: allenmchen@yahoo.com [Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California (United States)

2016-04-01

Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning—a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of “gentle IGRT.”.

Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

Directory of Open Access Journals (Sweden)

Dörr Harald

2011-11-01

Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

Diagnostic radiation risks

Energy Technology Data Exchange (ETDEWEB)

Sherwood, T [Addenbrooke' s Hospital, Cambridge (UK)

1980-04-01

A brief discussion on diagnostic radiation risks is given. First some fundamental facts on the concepts and units of radiation measurement are clarified. Medical diagnostic radiation doses are also compared to the radiation doses received annually by man from natural background radiation. The controversy concerning the '10-day rule' in X-raying women of child-bearing age is discussed; it would appear that the risk of malformation in an unborn child due to X-radiation is very much less than the natural level of risk of malformation. The differences in the radiographic techniques and thus the different X-ray doses needed to make adequate X-ray images of different parts of the body are considered. The radiation burden of nuclear medicine investigations compared to X-ray procedures is also discussed. Finally, the problems of using volunteers in radiation research are aired.

Diagnosis of acute radiation disease by enzyme immune-assay (EIA)

International Nuclear Information System (INIS)

Popov, D.; Maliev, V.

2005-01-01

of high levels of SDR-2, SDR-3 and SDR-4 in peripheral blood allowed to recognize early periods of toxic, gastrointestinal and typical forms of acute radiation sickness. Recognition of significantly high levels of SDR-4 is important for assessing radiation risks of mild typical radiation diseases (SDR-4/1), of moderate typical radiation diseases (SDR-4/2), of severe typical radiation diseases (SDR-4/3), of extremely severe typical radiation diseases (SDR-4/4). The important goal of early assessment with enzyme immune assay is the accurate description of started disease and most effectively managed therapy. The SDR EIA kit is a complete kit for the quantitative determination of different forms and levels of SDR-1, SDR-2, SDR-3, SDR-4 in a serum. This kit is a solid phase sandwich ELISA using 4 kinds of high specific antibodies. Visual assessment utilizes a 4 point scale (++++). The test was considered positive if the assessment was (++) or higher. Positive test allowed us to detect the presence and severity of radiation injury by identifying SDR forms and each from them was specific for different radiation energy and dependent on a volume of absorbed doses of radiation. (author)

Pathogenesis of acute radiation effects in the urinary bladder. Experimental results

International Nuclear Information System (INIS)

Doerr, W.; Eckhardt, M.; Ehme, A.; Koi, S.

1998-01-01

Purpose: The present review summarizes experimental studies of the pathogenesis of acute radiation-induced changes in urinary bladder function. Material and methods: Transurethral cystometry was used for longitudinal assessment of bladder function in mice. With this technique, radiation-induced changes in storage capacity can be quantified. In histological studies, changes in urothelial cell density and in urothelial protein expression during the acute radiation response were determined. Acetylsalicylic acid (ASA) was used for the treatment of acute functional changes. Results: The histological studies did not reveal any systematic fluctuations in urothelial cell density during the time of the acute radiation response. However, characteristic changes in the expression of proteins associated with urothelial cell function, differentiation and cell contact were observed, which correlated with the functional impairment. By local or systemical application of ASA, a significant restoration of bladder function compared to placebo treatment could be achieved. Conclusion: Acute functional radiation effects in the urinary bladder are not based on urothelial denudation. However, changes in protein expression indicate an impairment of the urothelial barrier function. The results of ASA treatment demonstrate that prostaglandins are involved in the response. Alterations in urothelial or endothelial prostaglandin metabolism may be primarily radiation-induced or secondary because of the impaired urothelial barrier. (orig.) [de

Clinical impact of predictive assays for acute and late radiation morbidity

International Nuclear Information System (INIS)

Budach, W.; Classen, J.; Belka, C.; Bamberg, M.

1998-01-01

Background: Clinically reliable predictive assays for normal tissue radiation sensitivity would help to avoid severe radiation induced morbidity and result in individualized dose prescriptions. Profound differences of individual fibroblast and lymphocyte radiation sensitivity in vitro have been documented in patients with certain genetic syndromes but also in patients without known genetic disorders. The following review evaluates whether fibroblast or lymphocyte radiation sensitivity measured in vitro correlates with the degree of acute and late radiation induced morbidity. Results: Acute radiation side effects and lymphocyte sensitivity has been investigated in 2 studies. One of them reported an insecure correlation, the other no correlation at all. Fibroblast radiation sensitivity and the extent of acute radiation induced side effects on skin and mucosal sites has been compared in a total of 5 studies. None of these studies found a consistent significant correlation. Lymphocyte radiation sensitivity and late effects have been studied by 2 institutions. Late radiation induced skin and mucosal changes did not correlate with lymphocyte sensitivity in head and neck cancer patients, whereas in breast cancer patients a weak (R 2 =0.06) correlation between the degree of late skin reactions and lymphocyte sensitivity was observed. Late skin or mucosal radiation reactions and fibroblast sensitivity were examined by 5 research groups. Data analysis revealed significant correlations or at least a trend towards a significant correlation in all studies. The quality of the reported correlations expressed as R 2 ranged from 0.13 to 0.60, indicating a low predictive value. Conclusions: Lymphocyte radiation sensitivity as measured by currently available assays does not or only poorly correlate with acute and late effects of radiation in patients, precluding predictive tests based on lymphocyte sensitivity. Fibroblast radiation sensitivity does not correlate with acute but

Radiation risk, medical surveillance programme and radiation protection in mining and milling of uranium ores

International Nuclear Information System (INIS)

Rakshit, A.K.

1991-01-01

Mining and milling of uranium ores comprise multiple operations such as developement, drilling, blasting, handling, crushing, grinding, leaching of the ore and concentration, drying, packaging and storing of the concentrate product. Apart from the hazards of any metal mining and milling operations due to dust, noise, chemicals, accidents etc there are radiation risks also resulting from exposure to airborne radioactivity and external radiation. The inhalation risk is of more concern in underground mines than in open pit mines. The objective of a Medical Surveillance Programme (an occupational Health Programme) is to ensure a healthy work force. It should ultimately lead to health maintenance and improvement, less absenteeism increased productivity and the achievement of worker and corporate goals. The programme includes prevention, acute care, counselling and rehabilitation. Radiological workers require special monitoring for their work-related radiation exposure effect by film monitoring service, whole body counting and bioassay. Radiation protection in the mining and milling of Uranium ores include the use of personal protective equipment, work station protection, personal hygiene and house keeping. (author). 15 refs

An Overview of NASA's Risk of Cardiovascular Disease from Radiation Exposure

Science.gov (United States)

Patel, Zarana S.; Huff, Janice L.; Simonsen, Lisa C.

2015-01-01

The association between high doses of radiation exposure and cardiovascular damage is well established. Patients that have undergone radiotherapy for primary cancers of the head and neck and mediastinal regions have shown increased risk of heart and vascular damage and long-term development of radiation-induced heart disease [1]. In addition, recent meta-analyses of epidemiological data from atomic bomb survivors and nuclear industry workers has also shown that acute and chronic radiation exposures is strongly correlated with an increased risk of circulatory disease at doses above 0.5 Sv [2]. However, these analyses are confounded for lower doses by lifestyle factors, such as drinking, smoking, and obesity. The types of radiation found in the space environment are significantly more damaging than those found on Earth and include galactic cosmic radiation (GCR), solar particle events (SPEs), and trapped protons and electrons. In addition to the low-LET data, only a few studies have examined the effects of heavy ion radiation on atherosclerosis, and at lower, space-relevant doses, the association between exposure and cardiovascular pathology is more varied and unclear. Understanding the qualitative differences in biological responses produced by GCR compared to Earth-based radiation is a major focus of space radiation research and is imperative for accurate risk assessment for long duration space missions. Other knowledge gaps for the risk of radiation-induced cardiovascular disease include the existence of a dose threshold, low dose rate effects, and potential synergies with other spaceflight stressors. The Space Radiation Program Element within NASA's Human Research Program (HRP) is managing the research and risk mitigation strategies for these knowledge gaps. In this presentation, we will review the evidence and present an overview of the HRP Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure.

Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

International Nuclear Information System (INIS)

Huang, Ellen X.; Bradley, Jeffrey D.; El Naqa, Issam; Hope, Andrew J.; Lindsay, Patricia E.; Bosch, Walter R.; Matthews, John W.; Sause, William T.; Graham, Mary V.; Deasy, Joseph O.

2012-01-01

Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non–small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose–volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior–inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 ∗ MED+1.50 ∗ ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis

Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Huang, Ellen X.; Bradley, Jeffrey D.; El Naqa, Issam [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Hope, Andrew J.; Lindsay, Patricia E. [Princess Margaret Hospital, Toronto, ON (Canada); Bosch, Walter R.; Matthews, John W. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO (United States); Sause, William T. [Department of Radiation Oncology, LDS Hospital, Salt Lake City, UT (United States); Graham, Mary V. [Department of Radiation Oncology, Phelps County Regional Hospital, Rolla, MO (United States); Deasy, Joseph O., E-mail: deasyj@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-04-01

Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 Asterisk-Operator MED+1.50 Asterisk-Operator ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts

Modeling the risk of radiation-induced acute esophagitis for combined Washington University and RTOG trial 93-11 lung cancer patients.

Science.gov (United States)

Huang, Ellen X; Bradley, Jeffrey D; El Naqa, Issam; Hope, Andrew J; Lindsay, Patricia E; Bosch, Walter R; Matthews, John W; Sause, William T; Graham, Mary V; Deasy, Joseph O

2012-04-01

To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non-small-cell lung cancer. The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose-volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior-inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 MED+1.50 ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis risk in combined-data WUSTL and RTOG 93-11 trial datasets. Copyright �

Effect of gene time on acute radiation mucositis and dermatitis

International Nuclear Information System (INIS)

Li Suyan; Gao Li; Yin Weibo; Xu Guozhen; Xiao Guangli

2002-01-01

Objective: To evaluate the effect of recombinant human epidermal growth factor (Gene Time) on acute mucositis and dermatitis induced by radiation. Methods: 120 head and neck cancer patients were randomized into 3 groups: 1. Mucositis prophylactic application (MPA) group with control, 2. Mucositis therapeutic application (MTA) group with control and 3. Dermatitis therapeutic application (DTA) group with control. Prophylactic application of drug consisted of spraying the Gene Time preparation on the irradiated skin or mucous membrane as radiotherapy was being carried out. This was compared with control patients who received routine conventional skin care. Therapeutic application was started as grade I radiation mucositis or dermatitis appeared. The evaluation of acute radiation mucositis and dermatitis was done according to the systems proposed by RTOG or EORTC. Results: The results showed that in the MPA group, the rate of radiation mucositis at ≤10 Gy was 20% (4/20) as compared to the 70% (14/20) of the control (P = 0.004). During the course of radiation, the incidences of grade III, IV acute radiation mucositis and dermatitis were always lower than the control. In therapeutic application of Gene Time, the response rate of acute radiation mucositis was also better than the control (90% vs 50%) (P = 0.016) and that of acute dermatitis was similar (95% vs 50%) (P = 0.005). Moreover, the ≤3 d rate of healing of grade III dermatitis in the application group was 3/7 as compared to the 0/14 of the control. Conclusion: Prophylactic application of recombinant human epidermal growth factor is able to postpone the development of radiation mucositis. This preparation is also able to lower the incidence of grade III, IV mucositis and dermatitis both by therapeutic and prophylactic application in addition to the hastened healing of grade III dermatitis

The role of radiation therapy in childhood acute leukemia. A review from the viewpoint of basic and clinical radiation oncology

International Nuclear Information System (INIS)

Nozaki, Miwako

2003-01-01

Radiation therapy has been playing important roles in the treatment of childhood acute leukemia since the 1970s. The first is the preventive cranial irradiation for central nervous system therapy in acute lymphoblastic leukemia. The second is the total body irradiation as conditioning before bone marrow transplantation for children with acute myeloid leukemia in first remission and with acute lymphoblastic leukemia in second remission. Although some late effects have been reported, a part of them could be overcome by technical improvement in radiation and salvage therapy. Radiation therapy for children might have a successful outcome on a delicate balance between efficiencies and potential late toxicities. The role of radiation therapy for childhood acute leukemia was reviewed from the standpoint of basic and clinical radiation oncology in this paper. (author)

Medical radiation exposure and genetic risks

International Nuclear Information System (INIS)

Baker, D.G.

1980-01-01

Everyone is exposed to background radiation throughout life (100 mrem/year to the gonads or 4 to 5 rem during the reproductive years). A lumbosacral series might deliver 2500 mrem to the male or 400 mrem to the female gonads. A radiologic procedure is a cost/benefit decision, and genetic risk is a part of the cost. Although cost is usually very low compared to benefit, if the procedure is unnecessary then the cost may be unacceptable. On the basis of current estimates, the doubling dose is assumed to be 40 rem (range 20 to 200) for an acute dose, and 100 rem for protracted exposure. Although there is no satisfactory way to predict the size of the risk for an individual exposed, any risk should be incentive to avoid unnecessary radiation to the gonads. Conception should be delayed for at least ten months for women and three or four months for men after irradiation of the gonads. The current incidence of genetically related diseases in the United States population is 60,000 per million live births. Based on the most conservative set of assumptions, an average gonadal dose of 1000 mrem to the whole population would increase the incidence of genetically related diseases by 0.2%

Suggested classification of acute radiation sickness

Energy Technology Data Exchange (ETDEWEB)

Yao, Guo; Mingyue, Zhu; Zhiqin, Zhao

1984-08-01

Acute radiation sickness is usually classified into three types. Over the last decade, we have been engaged in experimental studies on the classification of this syndrome. Our findings from these studies, however, point to the fact that between the hemopoietic and intestinal types, and between the intestinal and cerebral types there are transitive forms, namely, hemopoieto-intestinal type and cardio-vascular type, respectively. In this article the required radiation doses and the clinical courses of these transitive forms with special emphasis on their histological and clinical manifestations are described. In case of the hemopoieto-intestinal form, histological examination may reveal residual crypts and typical ''abnormal cells'' in the intestinal mucosa, and clinical manifestations include almost the whole spectrum of symptoms and signs of infection and hemorrhage. The watery stool in pink colour may be specific and helpful in diagnosis. In case of the cardio-vascular form, shock may occur immediately after exposure, and histological examination may show myocardial edema, hemorrhage, cell-infiltration and even necrosis. We propose that the acute radiation sickness should be divided into 5 forms, namely, hemopoietic, hemopoieto-intestinal, intestinal, cardio-vascular and cerebral types. Accurate diagnosis can only be made by taking an comprehensive view of radiation dose, clinical course, clinical manifestations and histological findings. (author).

Exposed persons at the Chernobyl Atomic Power Station accident: acute radiation effects

International Nuclear Information System (INIS)

Gus'kova, A.K.; Baranov, A.E.; Barabanova, A.V.

1987-01-01

Observation made over 115 patients with acute radiation sickness due to exposure external γ- and β-rays confirmed high efficiency of the earlier proposed principles of prognostication of the degree of severity by clinical manifestations of the primary disease response and those of separate syndromes, using the methods of hematological and cytogenetic analyses. Out of 115 victims, 56 persons had radiation burns (RB), 17 intestinal syndrome (IS), 80 - oropharengeal syndrome (ORS), 7 - interstitial radiation pneumonitis (IRP). In thanatogenesis, of prime importance were: RB (more than 40% of the body surface) - 19 persons and IRP - 7 persons. A severe course of intestinal and oropharengeal syndromes was combined with other fatal manifestations of radiation injury. Early isolation of patients (2-4 stages), selective decontamination of the intestine, prescription of a wide spectrum antibiotics, antimycotic and antiviral drugs, as well as γ-globulin could practically remove the risk of the development of fatal infectious complications during a medullary andtransitory forms of radiation sickness

Radiation protection standards: A practical exercise in risk assessment

Energy Technology Data Exchange (ETDEWEB)

Clarke, Roger H [National Radiological Protection Board (United Kingdom)

1992-07-01

Within 12 months of the discovery of x-rays in 1895, it was reported that large doses of radiation were harmful to living human tissues. The first radiation protection standards were set to avoid the early effects of acute irradiation. By the 1950s, evidence was mounting for late somatic effects - mainly a small excess of cancers - in irradiated populations. In the late 1980's, sufficient human epidemiological data had been accumulated to allow a comprehensive assessment of carcinogenic radiation risks following the delivery of moderately high doses. Workers and the public are exposed to lower doses and dose-rates than the groups from whom good data are available so that risks have had to be estimated for protection purposes. However, in the 1990s, some confirmation of these risk factors has been derived occupationally exposed populations. If an estimate is made of the risk per unit dose, then in order to set dose limits, an unacceptable level of risk must be established for both workers and the public. There has been and continues to be a debate about the definitions of 'acceptable' and 'tolerable' and the attributing of numerical values to these definitions. This paper discusses the issues involved in the quantification of these terms and their application to setting dose limits on risk grounds. Conclusions are drawn about the present protection standards and the application of the methods to other fields of risk assessment. (author)

Radiation protection standards: A practical exercise in risk assessment

International Nuclear Information System (INIS)

Clarke, Roger H.

1992-01-01

Within 12 months of the discovery of x-rays in 1895, it was reported that large doses of radiation were harmful to living human tissues. The first radiation protection standards were set to avoid the early effects of acute irradiation. By the 1950s, evidence was mounting for late somatic effects - mainly a small excess of cancers - in irradiated populations. In the late 1980's, sufficient human epidemiological data had been accumulated to allow a comprehensive assessment of carcinogenic radiation risks following the delivery of moderately high doses. Workers and the public are exposed to lower doses and dose-rates than the groups from whom good data are available so that risks have had to be estimated for protection purposes. However, in the 1990s, some confirmation of these risk factors has been derived occupationally exposed populations. If an estimate is made of the risk per unit dose, then in order to set dose limits, an unacceptable level of risk must be established for both workers and the public. There has been and continues to be a debate about the definitions of 'acceptable' and 'tolerable' and the attributing of numerical values to these definitions. This paper discusses the issues involved in the quantification of these terms and their application to setting dose limits on risk grounds. Conclusions are drawn about the present protection standards and the application of the methods to other fields of risk assessment. (author)

Intrarectal amifostine suspension may protect against acute proctitis during radiation therapy for prostate cancer: A pilot study

International Nuclear Information System (INIS)

Singh, Anurag K.; Menard, Cynthia; Guion, Peter; Simone, Nicole L.; Smith, Sharon; Crouse, Nancy Sears; Godette, Denise J.; Cooley-Zgela, Theresa; Sciuto, Linda C.; Coleman, Jonathan; Pinto, Peter; Albert, Paul S.; Camphausen, Kevin; Coleman, C. Norman

2006-01-01

Purpose: Our goal was to test the ability of intrarectal amifostine to limit symptoms of radiation proctitis. Methods and Materials: The first 18 patients received 1 g of intrarectal amifostine suspension placed 30-45 min before each radiation treatment. The following 12 patients received 2 g of amifostine. Total dose prescribed ranged from 66 to 76 Gy. All patients were treated with three-dimensional conformal radiation therapy. The suspension remained intrarectal during treatment and was expelled after treatment. For gastrointestinal symptoms, during treatment and follow-up, all patients had a Radiation Therapy Oncology Group (RTOG) grade recorded. Results: Median follow-up was 18 months (range, 6-24 months). With 2 g vs. 1 g amifostine, there was a nearly significant decrease in RTOG Grade 2 acute rectal toxicity. Seven weeks after the start of radiation therapy, the incidence of Grade 2 toxicity was 33% in the 1-g group (6/18) compared with 0% (0/12) in the 2-g group (p = 0.06). No Grade 3 toxicity or greater occurred in this study. Conclusion: This trial suggests greater rectal radioprotection from acute effects with 2 g vs. 1 g amifostine suspension. Further studies should be conducted in populations at higher risk for developing symptomatic acute and late proctitis

Diagnosis of moderate acute radiation sickness

International Nuclear Information System (INIS)

Yu Shoucheng; Chen Zhijian; Chen Youxin

1989-01-01

Forty patients with malignant lymphoma were given 60 Co TLI. 21 cases received 6 Gy and 19 received 8 Gy. It was estimated that a single TLI of 6 and 8 Gy would correspond to TBI of 3.55 Gy and 4.25 Gy (average values) by analysing peripheral blood cell chromosome aberrations and 1.85-2.37 Gy by measuring red bone marrow stem cells clinically. Moderate acute radiation sickness with digestive tract reaction and hemopoietic and immunologic depression was observed. WBC and platelets decreased rapidly. Lymphocytes showed quantitative and qualitative changes even at early stage. All these indexes are significant for diagnosis. Besides, the degree of labial stimulation response, levels of C-reactive protein, corticoid, and urinal nucleoside and alkaloid base presented great changes both pre-and post-irradiation. Early diagnosis of moderate acute radiation sickness could be made in cancer patients subjected to 6-8 Gy TLI

[Occupational risk related to optical radiation exposure in construction workers].

Science.gov (United States)

Gobba, F; Modenese, A

2012-01-01

Optical Radiation is a relevant occupational risk in construction workers, mainly as a consequence of the exposure to the ultraviolet (UV) component of solar radiation (SR). Available data show that UV occupational limits are frequently exceeded in these workers, resulting in an increased occupational risk of various acute and chronic effects, mainly to skin and to the eye. One of the foremost is the carcinogenic effect: SR is indeed included in Group 1 IARC (carcinogenic to humans). UV exposure is related to an increase of the incidence of basal cell carcinoma, squamous cell carcinoma of the skin and cutaneous malignant melanoma (CMM). The incidence of these tumors, especially CMM, is constantly increasing in Caucasians in the last 50 years. As a conclusion, an adequate evaluation of the occupational risk related to SR, and adequate preventive measures are essential in construction workers. The role of occupational physicians in prevention is fundamental.

Stem cell-based therapies for acute radiation syndrome

International Nuclear Information System (INIS)

Guha, Chandan

2014-01-01

Exposure to high doses of ionizing radiation in the event of accidental or intentional incident such as nuclear/radiological terrorism can lead to debilitating injuries to multiple organs resulting in death within days depending on the amount of radiation dose and the quality of radiation. Unfortunately, there is not a single FDA-licensed drug approved against acute radiation injury. The RadStem Center for Medical Countermeasures against Radiation (RadStem CMGR) program at Einstein is developing stem cell-based therapies to treat acute radiation syndrome (ARS). We have demonstrated that intravenous transplantation of bone marrow-derived and adipose-derived stromal cells, consisting of a mixture of mesenchymal, endothelial and myeloid progenitors can mitigate mice exposed to whole body irradiation of 12 Gy or whole abdominal irradiation of up to 20 Gy. We identified a variety of growth and differentiation factors that individually is unable to improve survival of animals exposed to lethal irradiation, but when administered sequentially mitigates radiation injury and improves survival. We termed this phenomenon as synthetic survival and describe a new paradigm whereby the 'synthetic survival' of irradiated tissues can be promoted by systemic administration of growth factors to amplify residual stem cell clonogens post-radiation exposure, followed by a differentiation factor that favors tissue stem cell differentiation. Synthetic survival can be applied to mitigate lethal radiation injury in multiple organs following radiation-induced hematopoeitic, gastrointestinal and pulmonary syndromes. (author)

Radiation and risk

International Nuclear Information System (INIS)

Jacobi, W.

1983-01-01

From the beginnings of the peaceful utilization of nuclear energy, the principles of prevention and optimization have greatly limited the emission of radioactive substances. In this way, the radiation exposure associated with emissions from nuclear power plants during normal operation has been kept low compared with natural radiation exposure and its variance. This also applies to the local public in the vicinities of such plants. The present health hazard to the public arising from ionizing radiation is only a small fraction of the man-made risk to which the public is exposed in this country. This is also due to the fact that radiation protection employs the principle of prevention, which has been laid down in legal regulations. In this respect, the concepts and criteria developed in radiation protection for evaluation, limitation and optimization may be useful examples to other areas of safety at work and environmental protection. The acceptance of nuclear power is decisively influenced by the remaining residual risk of accidents. Extremely careful inspection and supervision of the technical safety of such plants is indispensable to prevent major accidents. The German Risk Study for Nuclear Power Plants has made an important contribution to this end. It is being continued. However, risk research must always be accompanied by risk comparison to allow numerical risk data to be evaluated properly and important features to be distinguished from unimportant ones. (orig.) [de

Toxicity risk of non-target organs at risk receiving low-dose radiation: case report

International Nuclear Information System (INIS)

Shueng, Pei-Wei; Lin, Shih-Chiang; Chang, Hou-Tai; Chong, Ngot-Swan; Chen, Yu-Jen; Wang, Li-Ying; Hsieh, Yen-Ping; Hsieh, Chen-Hsi

2009-01-01

The spine is the most common site for bone metastases. Radiation therapy is a common treatment for palliation of pain and for prevention or treatment of spinal cord compression. Helical tomotherapy (HT), a new image-guided intensity modulated radiotherapy (IMRT), delivers highly conformal dose distributions and provides an impressive ability to spare adjacent organs at risk, thus increasing the local control of spinal column metastases and decreasing the potential risk of critical organs under treatment. However, there are a lot of non-target organs at risk (OARs) occupied by low dose with underestimate in this modern rotational IMRT treatment. Herein, we report a case of a pathologic compression fracture of the T9 vertebra in a 55-year-old patient with cholangiocarcinoma. The patient underwent HT at a dose of 30 Gy/10 fractions delivered to T8-T10 for symptom relief. Two weeks after the radiotherapy had been completed, the first course of chemotherapy comprising gemcitabine, fluorouracil, and leucovorin was administered. After two weeks of chemotherapy, however, the patient developed progressive dyspnea. A computed tomography scan of the chest revealed an interstitial pattern with traction bronchiectasis, diffuse ground-glass opacities, and cystic change with fibrosis. Acute radiation pneumonitis was diagnosed. Oncologists should be alert to the potential risk of radiation toxicities caused by low dose off-targets and abscopal effects even with highly conformal radiotherapy

Acute adverse effects of radiation therapy on HIV-positive patients in Japan. Study of 31 cases at Tokyo Metropolitan Komagome Hospital

International Nuclear Information System (INIS)

Kaminuma, Takuya; Karasawa, Katsuyuki; Hanyu, Nahoko

2010-01-01

Recently, the number of human immunodeficiency virus (HIV)-positive patients has increased in Japan. HIV-positive patients are at a higher risk of cancer than the general population. This paper retrospectively reports the acute adverse effects of radiation therapy on HIV-positive patients who were treated at Tokyo Metropolitan Cancer and Infectious diseases Center Komagome Hospital (TMCICK). Thirty-one cases involving 24 HIV-positive cancer patients who were treated at TMCICK from January 1997 to March 2009 were included in this study. All acute adverse effects of radiation therapy were examined during, and one month after, the last radiation therapy session. Acute adverse effects were classified according to the site of radiation therapy treatment and analyzed using the Common Terminology Criteria for Adverse Events (CTCAE) version 3.0. Grade 3 acute adverse effects were seen in 17% of cases, and Grade 2 toxicities were found in 23% of patients. Damage to the skin and mucosa, including stomatitis or diarrhea, tended to occur after low-dose radiation therapy; however, no severe acute adverse effects were seen in other organs, such as the brain, lung, and bone. Acute adverse effects tended to occur earlier in HIV-positive patients and became severe more frequently than in the general population. In particular, disorders of the mucosa, such as those of the oral cavity, pharynx, and intestine, tended to occur rapidly. It was shown that radiation therapy is safe when treatment is performed carefully and that it is a very useful treatment for cancer in HIV-positive patients. (author)

Radiation exposures: risks and realities

International Nuclear Information System (INIS)

Ganesh, G.

2010-01-01

Discovery of radioactivity in 1869 by Henry Becquerel and artificial radioactivity by Irene Curie in 1934 led to the development of nuclear field and nuclear materials in 20th century. They are widely used for man-kind across the globe in electricity production, carbon dating, treatment and diagnosis of diseases etc. While deriving benefits and utilizing nuclear resources for the benefit of man-kind, it is inevitable that exposure to radiation can not be avoided. Radiation exists all around us either natural or man-made which can not be totally eliminated or avoided. Radiation exposures from natural background contribute 2.4 to 3.6 mSv in a year. Radiation exposures incurred by a member of public due to nuclear industries constitute less than one hundredth of annual dose due to natural background. Hence it is important to understand the risk posed by radiation and comparison of radiation risk with various risks arising due to other sources. Studies have indicated that risks due to environmental pollution, cigarette smoking, alcohol consumption, heart diseases are far higher in magnitude compared to radiation risks from man made sources. This paper brings about the details and awareness regarding radiation exposures, radiation risk, various risks associated with other industries and benefits of radiation exposures. (author)

Single-centre experience of radiation exposure in acute surgical patients: assessment of therapeutic impact and future recommendations.

Science.gov (United States)

Fitzmaurice, Gerard J; Brown, Robin; Cranley, Brian; Conlon, Enda F; Todd, R Alan J; O'Donnell, Mark E

2010-09-01

Radiological investigations have become a key adjunct in patient management and consequently radiation exposure to patients is increasing. The study objectives were to examine the use of radiological investigations in the management of acute surgical patients and to assess whether a guideline-based radiation exposure risk/benefit analysis can aid in the choice of radiological investigation used. A prospective observational study was completed over a 12-week period from April to July 2008 for all acute surgical admissions. Data recorded included demographics, clinical presentation, differential diagnosis, investigations, surgical interventions, and final clinical outcome. The use of radiological investigative modalities as an adjunct to clinical assessment was then evaluated against The Royal College of Radiologists (RCR) guidelines. A total of 380 acute surgical admissions (M = 174, F = 185, children = 21) were assessed during the study period. Seven hundred thirty-four radiological investigations were performed with a mean of 1.93 investigations per patient. Based on the RCR guidelines, 680 (92.6%) radiological investigations were warranted and included 142 CT scans (19.3%), 129 chest X-rays (17.6%), and 85 abdominal X-rays (11.6%). Clinically, radiological imaging complemented surgical management in 326 patients (85.8%) and the management plan remained unchanged for the remaining 54 patients (14.2%). This accounted for an average radiation dose of 4.18 millisievert (mSv) per patient or 626 days of background radiation exposure. CT imaging was responsible for the majority of the radiation exposure, with a total of 1310 mSv (82.6%) of the total radiation exposure being attributed to CT imaging in 20.8% of acute admissions. Subgroup analysis demonstrated that 92.8% of the CT scans performed were appropriate. Radiation exposure was generally low for the majority of acute surgical admissions. However, it is recommended that CT imaging requests be evaluated carefully

Evaluation and management of acute radiation dermatitis

International Nuclear Information System (INIS)

Modesto, A.; Faivre, J.C.; Granel-Brocard, F.; Tao, Y.G.; Pointreau, Y.

2012-01-01

Acute radiation dermatitis remains one of the most commonly observed side effect during radiation therapy leading to complication such as superinfection or treatment disruption. Its management is characterized by a great heterogeneity. Few strategies have demonstrated a benefit in preventing radiation dermatitis, which relies mostly on decreasing dose delivered to the skin and skin care practices. Simple emollients and use of topical steroids can be useful in early stages. The singularity of the skin toxicity seen with cetuximab and radiotherapy warrants a specific grading system and distinctive clinical treatment with use of antibiotics. (authors)

Radiation Dose-Response Relationships and Risk Assessment

International Nuclear Information System (INIS)

Strom, Daniel J.

2005-01-01

The notion of a dose-response relationship was probably invented shortly after the discovery of poisons, the invention of alcoholic beverages, and the bringing of fire into a confined space in the forgotten depths of ancient prehistory. The amount of poison or medicine ingested can easily be observed to affect the behavior, health, or sickness outcome. Threshold effects, such as death, could be easily understood for intoxicants, medicine, and poisons. As Paracelsus (1493-1541), the 'father' of modern toxicology said, 'It is the dose that makes the poison.' Perhaps less obvious is the fact that implicit in such dose-response relationships is also the notion of dose rate. Usually, the dose is administered fairly acutely, in a single injection, pill, or swallow; a few puffs on a pipe; or a meal of eating or drinking. The same amount of intoxicants, medicine, or poisons administered over a week or month might have little or no observable effect. Thus, before the discovery of ionizing radiation in the late 19th century, toxicology ('the science of poisons') and pharmacology had deeply ingrained notions of dose-response relationships. This chapter demonstrates that the notion of a dose-response relationship for ionizing radiation is hopelessly simplistic from a scientific standpoint. While useful from a policy or regulatory standpoint, dose-response relationships cannot possibly convey enough information to describe the problem from a quantitative view of radiation biology, nor can they address societal values. Three sections of this chapter address the concepts, observations, and theories that contribute to the scientific input to the practice of managing risks from exposure to ionizing radiation. The presentation begins with irradiation regimes, followed by responses to high and low doses of ionizing radiation, and a discussion of how all of this can inform radiation risk management. The knowledge that is really needed for prediction of individual risk is presented

Changes in mast cells during acute radiation sickness(a morphometric study)

International Nuclear Information System (INIS)

Datsenko, A.V.; Shikhodyrov, V.V.

1985-01-01

Changes in the morphometric parameters of rat mast cells during acute radiation sickness have been studied. The most significant deviation of the quantitative indices of mast cells from the control values were noted at the height of the bone-marrow, at the terminal stage of the intestinal, and during the first few hours of the cerebral forms of acute radiation sickness

Statistical Prediction of Solar Particle Event Frequency Based on the Measurements of Recent Solar Cycles for Acute Radiation Risk Analysis

Science.gov (United States)

Myung-Hee, Y. Kim; Shaowen, Hu; Cucinotta, Francis A.

2009-01-01

Large solar particle events (SPEs) present significant acute radiation risks to the crew members during extra-vehicular activities (EVAs) or in lightly shielded space vehicles for space missions beyond the protection of the Earth's magnetic field. Acute radiation sickness (ARS) can impair performance and result in failure of the mission. Improved forecasting capability and/or early-warning systems and proper shielding solutions are required to stay within NASA's short-term dose limits. Exactly how to make use of observations of SPEs for predicting occurrence and size is a great challenge, because SPE occurrences themselves are random in nature even though the expected frequency of SPEs is strongly influenced by the time position within the solar activity cycle. Therefore, we developed a probabilistic model approach, where a cumulative expected occurrence curve of SPEs for a typical solar cycle was formed from a non-homogeneous Poisson process model fitted to a database of proton fluence measurements of SPEs that occurred during the past 5 solar cycles (19 - 23) and those of large SPEs identified from impulsive nitrate enhancements in polar ice. From the fitted model, the expected frequency of SPEs was estimated at any given proton fluence threshold (Phi(sub E)) with energy (E) >30 MeV during a defined space mission period. Corresponding Phi(sub E) (E=30, 60, and 100 MeV) fluence distributions were simulated with a random draw from a gamma distribution, and applied for SPE ARS risk analysis for a specific mission period. It has been found that the accurate prediction of deep-seated organ doses was more precisely predicted at high energies, Phi(sub 100), than at lower energies such as Phi(sub 30) or Phi(sub 60), because of the high penetration depth of high energy protons. Estimates of ARS are then described for 90th and 95th percentile events for several mission lengths and for several likely organ dose-rates. The ability to accurately measure high energy protons

Radiation risks in pregnancy

International Nuclear Information System (INIS)

Mossman, K.L.; Hill, L.T.

1982-01-01

A major contraindication of radiodiagnostic procedures is pregnancy. Approximately 1% of all pregnant women are given abdominal x-rays during the first trimester of pregnancy. Evaluation of radiation exposure should involve consideration of the types of examinations performed and when performed, as well as radiation dose and risk estimation. This information is then weighed against other possible risks of the pregnancy as well as personal factors. In the authors' experiences, radiation exposures usually result in doses to the embryo of less than 5 cGy (rad); the resulting radiation risks are usually small compared with other risks of pregnancy. Procedures to minimize diagnostic x-ray exposure of the fetus are also discussed

A suggested classification of acute radiation sickness

International Nuclear Information System (INIS)

Guo Yao; Zhu Mingyue; Zhao Zhiqin

1984-01-01

Acute radiation sickness is usually classified into three types. Over the last decade, we have been engaged in experimental studies on the classification of this syndrome. Our findings from these studies, however, point to the fact that between the hemopoietic and intestinal types, and between the intestinal and cerebral types there are transitive forms, namely, hemopoieto-intestinal type and cardio-vascular type, respectively. In this article the required radiation doses and the clinical courses of these transitive forms with special emphasis on their histological and clinical manifestations are described. In case of the hemopoieto-intestinal form, histological examination may reveal residual crypts and typical ''abnormal cells'' in the intestinal mucosa, and clinical manifestations include almost the whole spectrum of symptoms and signs of infection and hemorrhage. The watery stool in pink colour may be specific and helpful in diagnosis. In case of the cardio-vascular form, shock may occur immediately after exposure, and histological examination may show myocardial edema, hemorrhage, cell-infiltration and even necrosis. We propose that the acute radiation sickness should be divided into 5 forms, namely, hemopoietic, hemopoieto-intestinal, intestinal, cardio-vascular and cerebral types. Accurate diagnosis can only be made by taking an comprehensive view of radiation dose, clinical course, clinical manifestations and histological findings. (author)

Risks for radiation workers

International Nuclear Information System (INIS)

Rotblat, J.

1978-01-01

The following topics are discussed: recommendations of the International Commission on Radiological Protection; methods for determining dose limits to workers; use of data from survivors of Hiroshima and Nagasaki for estimating risk factors; use of data from survivors of nuclear explosions in Marshall Islands, uranium miners, and patients exposed to diagnostic and therapeutic radiation; risk factors for radioinduced malignancies; evidence that risk factors for persons exposed to partial-body radiation and Japanese survivors are too low; greater resistance of A-bomb survivors to radiation; and radiation doses received by U.K. medical workers and by U.K. fuel reprocessing workers. It is suggested that the dose limit for radiation workers should be reduced by a factor of 5

Perception of low dose radiation risks among radiation researchers in Korea

Science.gov (United States)

Seo, Songwon; Lee, Dalnim; Park, Sunhoo; Jin, Young Woo; Lee, Seung-Sook

2017-01-01

Expert’s risk evaluation of radiation exposure strongly influences the public’s risk perception. Experts can inform laypersons of significant radiation information including health knowledge based on experimental data. However, some experts’ radiation risk perception is often based on non-conclusive scientific evidence (i.e., radiation levels below 100 millisievert), which is currently under debate. Examining perception levels among experts is important for communication with the public since these individual’s opinions have often exacerbated the public’s confusion. We conducted a survey of Korean radiation researchers to investigate their perceptions of the risks associated with radiation exposure below 100 millisievert. A linear regression analysis revealed that having ≥ 11 years’ research experience was a critical factor associated with radiation risk perception, which was inversely correlated with each other. Increased opportunities to understand radiation effects at risk perception of radiation exposure. In addition, radiation researchers conceived that more scientific evidence reducing the uncertainty for radiation effects risk perception of radiation exposure. PMID:28166286

Defining AML and MDS second cancer risk dynamics after diagnoses of first cancers treated or not with radiation

NARCIS (Netherlands)

Radivoyevitch, T.; Sachs, R. K.; Gale, R. P.; Molenaar, R. J.; Brenner, D. J.; Hill, B. T.; Kalaycio, M. E.; Carraway, H. E.; Mukherjee, S.; Sekeres, M. A.; Maciejewski, J. P.

2016-01-01

Risks of acute myeloid leukemia (AML) and/or myelodysplastic syndromes (MDS) are known to increase after cancer treatments. Their rise-and-fall dynamics and their associations with radiation have, however, not been fully characterized. To improve risk definition we developed SEERaBomb R software for

[Solar radiation exposure in agriculture: an underestimated risk].

Science.gov (United States)

Gobba, F

2012-01-01

Solar Radiation (SR) is a major occupational risk in agriculture, mainly related to its ultraviolet (UV) component. Available data show that UV occupational limits are frequently exceeded in these workers, resulting in an increased occupational risk of various acute and chronic effects, mainly to skin and to the eye. One of the foremost is the carcinogenic effect: SR is indeed included in Group 1 IARC (carcinogenic to humans). UV exposure is related to an increase of the incidence of basal cell carcinoma and squamous cell carcinoma of the skin, and cutaneous malignant melanoma (CMM). The incidence of these tumors, especially CMM, is constantly increasing in Caucasians in the last 50 years. As a conclusion, an adequate evaluation of the occupational risk related to SR, and adequate preventive measures are essential in agriculture. The role of the Occupational Physician in prevention is fundamental.

Acute Lymphocytic Leukemia

Science.gov (United States)

... that may increase the risk of acute lymphocytic leukemia include: Previous cancer treatment. Children and adults who've had certain types of chemotherapy and radiation therapy for other kinds of cancer may have an increased ... leukemia. Exposure to radiation. People exposed to very high ...

The 15-Country Collaborative Study of Cancer Risk Among Radiation Workers in the Nuclear Industry

DEFF Research Database (Denmark)

Vrijheid, M; Cardis, E; Blettner, M

2007-01-01

Radiation protection standards are based mainly on risk estimates from studies of atomic bomb survivors in Japan. The validity of extrapolations from the relatively high-dose acute exposures in this population to the low-dose, protracted or fractionated environmental and occupational exposures...

Cancer risk as a radiation detriment

International Nuclear Information System (INIS)

Servomaa, A.; Komppa, T.; Servomaa, K.

1992-11-01

Potential radiation detriment means a risk of cancer or other somatic disease, genetic damage of fetal injury. Quantative information about the relation between a radiation dose and cancer risk is needed to enable decision-making in radiation protection. However, assessment of cancer risk by means of the radiation dose is controversial, as epidemiological and biological information about factors affecting the origin of cancers show that risk assessment is imprecise when the radiation dose is used as the only factor. Focusing on radiation risk estimates for breast cancer, lung cancer and leukemia, the report is based on the models given in the Beir V report, on sources of radiation exposure and the uncertainty of risk estimates. Risk estimates are assessed using the relative risk model and the cancer mortality rates in Finland. Cancer incidence and mortality rates for men and women are shown in graphs as a function of age and time. Relative risks are shown as a function of time after exposure and lifetime risks as a function of age at exposure. Uncertainty factors affecting the radiation risk are examined from the point of view of epidemiology and molecular biology. (orig.)

Acute Radiation Syndrome Severity Score System in Mouse Total-Body Irradiation Model.

Science.gov (United States)

Ossetrova, Natalia I; Ney, Patrick H; Condliffe, Donald P; Krasnopolsky, Katya; Hieber, Kevin P

2016-08-01

Radiation accidents or terrorist attacks can result in serious consequences for the civilian population and for military personnel responding to such emergencies. The early medical management situation requires quantitative indications for early initiation of cytokine therapy in individuals exposed to life-threatening radiation doses and effective triage tools for first responders in mass-casualty radiological incidents. Previously established animal (Mus musculus, Macaca mulatta) total-body irradiation (γ-exposure) models have evaluated a panel of radiation-responsive proteins that, together with peripheral blood cell counts, create a multiparametic dose-predictive algorithm with a threshold for detection of ~1 Gy from 1 to 7 d after exposure as well as demonstrate the acute radiation syndrome severity score systems created similar to the Medical Treatment Protocols for Radiation Accident Victims developed by Fliedner and colleagues. The authors present a further demonstration of the acute radiation sickness severity score system in a mouse (CD2F1, males) TBI model (1-14 Gy, Co γ-rays at 0.6 Gy min) based on multiple biodosimetric endpoints. This includes the acute radiation sickness severity Observational Grading System, survival rate, weight changes, temperature, peripheral blood cell counts and radiation-responsive protein expression profile: Flt-3 ligand, interleukin 6, granulocyte-colony stimulating factor, thrombopoietin, erythropoietin, and serum amyloid A. Results show that use of the multiple-parameter severity score system facilitates identification of animals requiring enhanced monitoring after irradiation and that proteomics are a complementary approach to conventional biodosimetry for early assessment of radiation exposure, enhancing accuracy and discrimination index for acute radiation sickness response categories and early prediction of outcome.

Scintigraphic and Endoscopic Evaluation of Radiation-induced Acute Gastrointestinal Syndrome in Micro-pig Model

International Nuclear Information System (INIS)

Lee, Seung-Sook; Kim, Kyung-Min; Kim, Jin; Jang, Won-Suk; Lee, Jung-Eun; Kim, Noo-Ri; Lee, Sun-Joo; Kim, Mi-Sook; Ji, Young-Hoon; Cheon, Gi-Jeong; Lim, Sang-Moo

2007-01-01

Micro-pig model can be served as a proper substitute for humans in studying acute radiation syndrome following radiation-exposure accidents, especially showing similar clinico-pathologic response of hematopoietic and gastrointestinal (GI) syndrome to human. Among acute GI syndrome induced by radiation, GI motility disturbance has not been studied, however, it would be important in a viewpoint of affecting infectious progression from GI tract. Here, we employed scintigraphy of GI transit time and sequential endoscopic examination and tissue sampling in micropigs followed by abdominal radiation exposure. The specific aims of this study are to evaluate objective evidence of GI motility disturbance by scintigraphic evaluation and to find corresponding clinicoapthologic changes in radiation-induced acute GI syndrome

Serial Diffusion Tensor Imaging of the Optic Radiations after Acute Optic Neuritis

Directory of Open Access Journals (Sweden)

Scott C. Kolbe

2016-01-01

Full Text Available Previous studies have reported diffusion tensor imaging (DTI changes within the optic radiations of patients after optic neuritis (ON. We aimed to study optic radiation DTI changes over 12 months following acute ON and to study correlations between DTI parameters and damage to the optic nerve and primary visual cortex (V1. We measured DTI parameters [fractional anisotropy (FA, axial diffusivity (AD, radial diffusivity (RD, and mean diffusivity (MD] from the optic radiations of 38 acute ON patients at presentation and 6 and 12 months after acute ON. In addition, we measured retinal nerve fibre layer thickness, visual evoked potential amplitude, optic radiation lesion load, and V1 thickness. At baseline, FA was reduced and RD and MD were increased compared to control. Over 12 months, FA reduced in patients at an average rate of −2.6% per annum (control = −0.51%; p=0.006. Change in FA, RD, and MD correlated with V1 thinning over 12 months (FA: R=0.450, p=0.006; RD: R=-0.428, p=0.009; MD: R=-0.365, p=0.029. In patients with no optic radiation lesions, AD significantly correlated with RNFL thinning at 12 months (R=0.489, p=0.039. In conclusion, DTI can detect optic radiation changes over 12 months following acute ON that correlate with optic nerve and V1 damage.

Radiation risk and radiation protection concepts

International Nuclear Information System (INIS)

Doerschel, B.

1989-01-01

The revised dosimetry for the survivors of Hiroshima and Nagasaki implies an increased risk from low LET radiation compared with that currently used. During its meeting in 1987 the ICRP stated that the new data at present do not require any change in the dose limits. However, two other factors can cause larger changes in the present risk estimates. Firstly, for some types of cancer the relative risk model seems to describe the observed data better than the absolute risk model currently used by the ICRP. Secondly, the shape of the dose-response relationship considerably influences the derived risks. In the present paper the factor causing a substantial increase in radiation risk are analyzed. Conclusions are drawn in how far a change in the currently recommended dose limits seems to be necessary. (author)

New radiobiological, radiation risk and radiation protection paradigms

International Nuclear Information System (INIS)

Goodhead, Dudley T.

2010-01-01

The long-standing conventional paradigm for radiobiology has formed a logical basis for the standard paradigm for radiation risk of cancer and heritable effects and, from these paradigms, has developed the internationally applied system for radiation protection, but with many simplifications, assumptions and generalizations. A variety of additional radiobiological phenomena that do not conform to the standard paradigm for radiobiology may have potential implications for radiation risk and radiation protection. It is suggested, however, that the current state of knowledge is still insufficient for these phenomena, individually or collectively, to be formulated systematically into a new paradigm for radiobiology. Additionally, there is at present lack of direct evidence of their relevance to risk for human health, despite attractive hypotheses as to how they might be involved. Finally, it remains to be shown how incorporation of such phenomena into the paradigm for radiation protection would provide sufficient added value to offset disruption to the present widely applied system. Further research should aim for better mechanistic understanding of processes such as radiation-induced genomic instability (for all radiation types) and bystander effects (particularly for low-fluence high-LET particles) and also priority should be given to confirmation, or negation, of the relevance of the processes to human health risks from radiation.

Moist skin care can diminish acute radiation-induced skin toxicity

International Nuclear Information System (INIS)

Momm, F.; Weissenberger, C.; Bertelt, S.; Henke, M.

2003-01-01

Background: Radiation treatment may induce acute skin reactions. There are several methods of managing them. Validity of these methods, however, is not sufficiently studied. We therefore investigated, whether moist skin care with 3% urea lotion will reduce acute radiation skin toxicity. Patients and Methods: 88 patients with carcinomas of the head and neck undergoing radiotherapy with curative intent (mean total dose 60 Gy, range: 50-74 Gy) were evaluated weekly for acute skin reactions according to the RTOG-CTC score. In 63 patients, moist skin care with 3% urea lotion was performed. The control group consisted of 25 patients receiving conventional dry skin care. The incidence of grade I, II, and III reactions and the radiation dose at occurrence of a particular reaction were determined and statistically analyzed using the log-rank test. The dose-time relations of individual skin reactions are described. Results: At some point of time during radiotherapy, all patients suffered from acute skin reactions grade I, > 90% from grade II reactions. 50% of patients receiving moist skin care experienced grade I reactions at 26 Gy as compared to 22 Gy in control patients (p = 0.03). Grade II reactions occurred at 51 Gy versus 34 Gy (p = 0.006). Further, 22% of the patients treated with moist skin care suffered from acute skin toxicity grade III as compared to 56% of the controls (p = 0.0007). Conclusion: Moist skin care with 3% urea lotion delays the occurrence and reduces the grade of acute skin reactions in percutaneously irradiated patients with head and neck tumors. (orig.)

Radiation exposure and radiation risk of the population

International Nuclear Information System (INIS)

Jacobi, W.; Paretzke, H.G.; Ehling, U.H.

1981-02-01

The major scientifically founded results concerning the assessment of the radiation exposure and the analysis and evaluation of the radiationhazards for the population, particularly in the range of low doses, are presented. As to the risk analysis special attention is paid to the rays with low ionization density (X-, γ-, β- and electronrays). Contents: 1) Detailed survey of the results and conclusions; 2) Data on the radiation load of the population; 3) Results to epidemiological questioning on the risk of cancer; 4) Genetical radiation hazards of the population. For quantification purposes of the risk of cancer by γ-radiation the observations with the a-bomb survivors in Japan are taken as a basis, as the available dosimetrical data have to be revised. Appendices: 1) German translation of the UNSCEAR-Report (1977); 2) BEIR-Report (1980); 3) Comments from the SSK on the comparability of the risks of natural-artificial radiation exposure; 4) Comments from the SSK on the importance of synergistical influences for the radiation protection (23.9.1977). (HP) [de

Radiation risk estimation

International Nuclear Information System (INIS)

Schull, W.J.; Texas Univ., Houston, TX

1992-01-01

Estimation of the risk of cancer following exposure to ionizing radiation remains largely empirical, and models used to adduce risk incorporate few, if any, of the advances in molecular biology of a past decade or so. These facts compromise the estimation risk where the epidemiological data are weakest, namely, at low doses and dose rates. Without a better understanding of the molecular and cellular events ionizing radiation initiates or promotes, it seems unlikely that this situation will improve. Nor will the situation improve without further attention to the identification and quantitative estimation of the effects of those host and environmental factors that enhance or attenuate risk. (author)

Ionizing radiation: benefits vs. risks

International Nuclear Information System (INIS)

Wagner, H.N. Jr.

1986-01-01

No one has been identifiably injured by radiation within the levels set by the NCRP and ICRP in 1934. This fact and the level of natural radiation (average dose 102 millirems/year) help provide standards against which the authors can view the relative increases in exposure from manmade sources of radiation. Because one person in five in the US will die of cancer from all causes, it is impossible to detect small increases in some types of cancer from radiation. A valid assumption is that any exposure to radiation carries some possibility of harm and should be kept below the level of the expected benefits. More is known about radiation toxicity than about any other potentially toxic substances. An obstacle to progress in the use of radioactive materials in biology and medicine is an exaggerated impression by the public of the risk of radiation. Several studies indicate that the public perceives the risk of radiation to be the greatest of all societal risks and at times does not distinguish peaceful from military uses of radiation. It behooves scientists and physicians to inform the public about the benefits as well as the risks of procedures involving radiation

Perception of low dose radiation risks among radiation researchers in Korea.

Science.gov (United States)

Seong, Ki Moon; Kwon, TaeWoo; Seo, Songwon; Lee, Dalnim; Park, Sunhoo; Jin, Young Woo; Lee, Seung-Sook

2017-01-01

Expert's risk evaluation of radiation exposure strongly influences the public's risk perception. Experts can inform laypersons of significant radiation information including health knowledge based on experimental data. However, some experts' radiation risk perception is often based on non-conclusive scientific evidence (i.e., radiation levels below 100 millisievert), which is currently under debate. Examining perception levels among experts is important for communication with the public since these individual's opinions have often exacerbated the public's confusion. We conducted a survey of Korean radiation researchers to investigate their perceptions of the risks associated with radiation exposure below 100 millisievert. A linear regression analysis revealed that having ≥ 11 years' research experience was a critical factor associated with radiation risk perception, which was inversely correlated with each other. Increased opportunities to understand radiation effects at perception of radiation exposure. In addition, radiation researchers conceived that more scientific evidence reducing the uncertainty for radiation effects perception of radiation exposure.

Management of radiation risk

International Nuclear Information System (INIS)

Hubert, P.

1996-01-01

The need to control the risk from ionizing radiation can be tracked back to the eve of the twentieth century. However, as knowledge improved and practices expanded, the approaches to this control have evolved. No longer is the mere respect of some forms of exposure limits or safety related standards sufficient. Rather, it is widely admitted that there is a need for managing radiation risk, both by balancing the advantages and disadvantages of enhancing protection and by setting up a proper organization that allows handling of the risk. This paper describes the multiple aspects of radiation risk management and points out the main related issues. It critically analyzes ALARA and ICRP recommendations. 74 refs, 8 figs, 5 tabs

Fundamental matters on radiation risk communication

International Nuclear Information System (INIS)

Shinohara, Kunihiko; Nagai, Hiroyuki; Yonezawa, Rika; Ohuchi, Hiroko; Chikamoto, Kazuhiko; Taniguchi, Kazufumi; Morimoto, Eriko

2009-01-01

In the field of atomic energy and radiation utilization, radiation risk is considered as one of the social uneasy factors. About the perception of risks, there is a gap between experts and general public (non-experts). It is said that the general public tends to be going to judge risk from intuitive fear and a visible concrete instance whereas the experts judge it scientifically. A company, an administration or experts should disclose relating information about the risks and communicate interactively with the stakeholders to find the way to solve the problem with thinking together. This process is called 'risk communication'. The role of the expert is important on enforcement of risk communication. They should be required to explain the information on the risks with plain words to help stakeholders understand the risks properly. The Japan Health Physics Society (JHPS) is the largest academic society for radiation protection professionals in Japan, and one of its missions is supposed to convey accurate and trustworthy information about the radiation risk to the general public. The expert group on risk communication of ionizing radiation of the JHPS has worked for the purpose of summarizing the fundamental matters on radiation risk communication. 'Lecture on risk communication for the members of the JHPS.' which has been up on the JHPS web-site, and the symposium of 'For better understanding of radiation risk.' are a part of the activities. The expert group proposes that the JHPS should enlighten the members continuously for being interested in and practicing risk communication of radiation. (author)

The Increase in Animal Mortality Risk following Exposure to Sparsely Ionizing Radiation Is Not Linear Quadratic with Dose.

Directory of Open Access Journals (Sweden)

Benjamin M Haley

Full Text Available The US government regulates allowable radiation exposures relying, in large part, on the seventh report from the committee to estimate the Biological Effect of Ionizing Radiation (BEIR VII, which estimated that most contemporary exposures- protracted or low-dose, carry 1.5 fold less risk of carcinogenesis and mortality per Gy than acute exposures of atomic bomb survivors. This correction is known as the dose and dose rate effectiveness factor for the life span study of atomic bomb survivors (DDREFLSS. It was calculated by applying a linear-quadratic dose response model to data from Japanese atomic bomb survivors and a limited number of animal studies.We argue that the linear-quadratic model does not provide appropriate support to estimate the risk of contemporary exposures. In this work, we re-estimated DDREFLSS using 15 animal studies that were not included in BEIR VII's original analysis. Acute exposure data led to a DDREFLSS estimate from 0.9 to 3.0. By contrast, data that included both acute and protracted exposures led to a DDREFLSS estimate from 4.8 to infinity. These two estimates are significantly different, violating the assumptions of the linear-quadratic model, which predicts that DDREFLSS values calculated in either way should be the same.Therefore, we propose that future estimates of the risk of protracted exposures should be based on direct comparisons of data from acute and protracted exposures, rather than from extrapolations from a linear-quadratic model. The risk of low dose exposures may be extrapolated from these protracted estimates, though we encourage ongoing debate as to whether this is the most valid approach. We also encourage efforts to enlarge the datasets used to estimate the risk of protracted exposures by including both human and animal data, carcinogenesis outcomes, a wider range of exposures, and by making more radiobiology data publicly accessible. We believe that these steps will contribute to better estimates

Evaluation of acute radiation optic neuropathy by B-scan ultrasonography

International Nuclear Information System (INIS)

Lovato, A.A.; Char, D.H.; Quivey, J.M.; Castro, J.R.

1990-01-01

We studied the accuracy of B-scan ultrasonography to diagnose radiation-induced optic neuropathy in 15 patients with uveal melanoma. Optic neuropathy was diagnosed by an observer masked as to clinical and photographic data. We analyzed planimetry area measurements of the retrobulbar nerve before and after irradiation. The retrobulbar area of the optic nerve shadow on B-scan was quantitated with a sonic digitizer. Increased optic nerve shadow area was confirmed in 13 of 15 patients who had radiation optic neuropathy (P less than .004). The correct diagnosis was confirmed when the results of ultrasound were compared to fundus photography and fluorescein angiography. In 13 patients there was acute radiation optic neuropathy. Two patients did not show an enlarged retrobulbar optic nerve, and the clinical appearance suggested early progression to optic atrophy. Ultrasonography documents the enlargement of the optic nerve caused by acute radiation changes

Current features on risk perception and risk communication of radiation

International Nuclear Information System (INIS)

Kusama, Tomoko

1997-01-01

Health effects and risks of radiation and radionuclides are being misunderstood by many members of general public. Many peoples have fear and anxieties for radiation. So far, the health effects from radiation at low dose and low dose rate have not been cleared on biological aspects. Then, we have quantitatively estimated health risks of low-dose radiation on the basis of linear dose response relationship without threshold from the viewpoints of radiation protection by using both epidemiological data, such as atomic bomb survivors, and some models and assumptions. It is important for researchers and relevant persons in radiation protection to understand the process of risk estimation of radiation and to communicate an exact knowledge of radiation risks of the public members. (author)

Relations between radiation risks and radiation protection measuring techniques

International Nuclear Information System (INIS)

Herrmann, K.; Kraus, W.

Relations between radiation risks and radiation protection measuring techniques are considered as components of the radiation risk. The influence of the exposure risk on type and extent of radiation protection measurements is discussed with regard to different measuring tasks. Based upon measuring results concerning the frequency of certain external and internal occupational exposures in the GDR, it has been shown that only a small fraction of the monitored persons are subjected to a high exposure risk. As a consequence the following recommendations are presented: occupationally exposed persons with small exposure risk should be monitored using only a long-term desimeter (for instance a thermoluminescence desimeter). In the case of internal exposure, the surface and air contamination levels should be controlled so strictly that routine measurements of internal contamination need not be performed

Effective doses and standardised risk factors from paediatric diagnostic medical radiation exposures: Information for radiation risk communication

International Nuclear Information System (INIS)

Bibbo, Giovanni

2018-01-01

In the paediatric medical radiation setting, there is no consistency on the radiation risk information conveyed to the consumer (patient/carer). Each communicator may convey different information about the level of risk for the same radiation procedure, leaving the consumer confused and frustrated. There is a need to standardise risks resulting from medical radiation exposures. In this study, paediatric radiographic, fluoroscopic, CT and nuclear medicine examination data have been analysed to provide (i) effective doses and radiation induced cancer risk factors from common radiological and nuclear medicine diagnostic procedures in standardised formats, (II) awareness of the difficulties that may be encountered in communicating risks to the layperson, and (iii) an overview of the deleterious effects of ionising radiation so that the risk communicator can convey with confidence the risks resulting from medical radiation exposures. Paediatric patient dose data from general radiographic, computed tomography, fluoroscopic and nuclear medicine databases have been analysed in age groups 0 to <5 years, 5 to <10 years, 10 to <15 years and 15 to <18 years to determine standardised risk factors. Mean, minimum and maximum effective doses and the corresponding mean lifetime risks for general radiographic, fluoroscopic, CT and nuclear medicine examinations for different age groups have been calculated. For all examinations, the mean lifetime cancer induction risk is provided in three formats: statistical, fraction and category. Standardised risk factors for different radiological and nuclear medicine examinations and an overview of the deleterious effects of ionising radiation and the difficulties encountered in communicating the risks should facilitate risk communication to the patient/carer.

The risk philosophy of radiation protection

International Nuclear Information System (INIS)

Lindell, B.

1996-01-01

The processes of risk assessment and risk evaluation are described. The assumptions behind current radiation risk assessments, which are focused on the probability of attributable death from radiation-induced cancer, are reviewed. These assessments involve projection models to take account of future cancer death in irradiated populations, the transfer of risk estimates between populations and the assumptions necessary to derive risk assessments for low radiation doses from actual observations at high doses. The paper ends with a presentation of the basic radiation protection recommendations of the International Commission on Radiological Protection (ICRP) in the context of a risk philosophy. (author)

Low dose diagnostic radiation does not increase cancer risk in cancer prone mice

Energy Technology Data Exchange (ETDEWEB)

Boreham, D., E-mail: dboreham@nosm.ca [Northern Ontario School of Medicine, ON (Canada); Phan, N., E-mail: nghiphan13@yahoo.com [Univ. of Ottawa, Ottawa, ON (Canada); Lemon, J., E-mail: lemonja@mcmaster.ca [McMaster Univ., Hamilton, ON (Canada)

2014-07-01

The increased exposure of patients to low dose diagnostic ionizing radiation has created concern that these procedures will result in greater risk of carcinogenesis. However, there is substantial evidence that shows in many cases that low dose exposure has the opposite effect. We have investigated whether CT scans can modify mechanisms associated with carcinogenesis in cancer-prone mice. Cancer was induced in Trp53+/- mice with an acute high dose whole-body 4 Gy γ-radiation exposure. Four weeks following the cancer-inducing dose, weekly whole-body CT scans (10 mGy/scan, 75 kVp X-rays) were given for ten consecutive weeks adding an additional radiation burden of 0.1 Gy. Short-term biological responses and subsequent lifetime cancer risk were investigated. Five days following the last CT scan, there were no detectable differences in the spontaneous levels of DNA damage in blood cells (reticulocytes). In fact, CT scanned mice had significantly lower constitutive levels of oxidative DNA damage and cell death (apoptosis), compared to non-CT scanned mice. This shows that multiple low dose radiation exposures modified the radio response and indicates protective processes were induced in mice. In mice treated with the multiple CT scans following the high cancer-inducing 4 Gy dose, tumour latency was increased, significantly prolonging lifespan. We conclude that repeated CT scans can reduce the cancer risk of a prior high-dose radiation exposure, and delay the progression of specific types of radiation-induced cancers in Trp53+/-mice. This research shows for the first time that low dose exposure long after cancer initiation events alter risk and reduce cancer morbidity. Cancer induction following low doses does not follow a linear non-threshold model of risk and this model should not be used to extrapolate risk to humans following low dose exposure to ionizing radiation. (author)

Competing risk theory and radiation risk assessment

International Nuclear Information System (INIS)

Groer, P.G.

1980-01-01

New statistical procedures are applied to estimate cumulative distribution functions (c.d.f.), force of mortality, and latent period for radiation-induced malignancies. It is demonstrated that correction for competing risks influences the shape of dose response curves, estimates of the latent period, and of the risk from ionizing radiations. The equivalence of the following concepts is demonstrated: force of mortality, hazard rate, and age or time specific incidence. This equivalence makes it possible to use procedures from reliability analysis and demography for radiation risk assessment. Two methods used by reliability analysts - hazard plotting and total time on test plots - are discussed in some detail and applied to characterize the hazard rate in radiation carcinogenesis. C.d.f.'s with increasing, decreasing, or constant hazard rate have different shapes and are shown to yield different dose-response curves for continuous irradiation. Absolute risk is shown to be a sound estimator only if the force of mortality is constant for the exposed and the control group. Dose-response relationships that use the absolute risk as a measure for the effect turn out to be special cases of dose-response relationships that measure the effect with cumulative incidence. (H.K.)

Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

Science.gov (United States)

Chancellor, Jeffery C.; Scott, Graham B. I.; Sutton, Jeffrey P.

2014-01-01

Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO). Shielding is an effective countermeasure against solar particle events (SPEs), but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR) nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts. PMID:25370382

Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

Directory of Open Access Journals (Sweden)

Jeffery C. Chancellor

2014-09-01

Full Text Available Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO. Shielding is an effective countermeasure against solar particle events (SPEs, but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts.

Acute irradiation syndrome : radiation disease

International Nuclear Information System (INIS)

Mestries, J.C.; Multon, E.

1995-01-01

It is classically assumed that the symptomatology of the acute radiation syndrome is mainly due to stem and progenitor cells death in compartimentalized tissues, particularly in bone marrow and intestine. Our observations on baboons, irradiated with a mixed neutron/gamma or a gamma radiation, showed that the whole organism response plays a major role. There is an inflammatory syndrome, not only during the prodromal phase, but also a second one, that precedes and accompanies the manifest-illness phase. This inflammatory syndrome was associated with coagulation disorders which are largely responsible for bleeding. This syndrome makes the therapeutic approach more complicated since some cytokines, which could be able to improve the hematopoietic cells recovery (e.g. IL-6), exhibit pro-inflammatory activities as well. Regarding radiobiological triage, no biological marker has a prognosis value during the first days following a radiation exposure, for those individuals exposed to around a LD50. On the contrary, some inflammation markers allow to anticipate a fatal issue, without any treatment, as early as the beginning of the manifest-illness phase. (authors). 10 refs., 11 figs

The risks of radiation

Science.gov (United States)

Miettenen, Jorma K.

1988-01-01

The risks of radioactivity are a really complicated matter, yet they are much better known than are the risks relating to thousands of chemical poisons that occur in our environment. The greatest mistakes are probably made in the definition of safety margins. Except for the bombs dropped in Japan and one other case in the Marshall Islands, there has always—luckily—been a wide safety margin between fallout radiation and doses dangerous to health; the margin has actually been about 1000-fold. The Chernobyl dose of 0.5 mGy/year that we received is only 1/1000 of the acute dose of 0.5 Gy which would cause a slight and nonpermanent change in the blood picture. There is no such safety margin with respect to many air pollutants. The safety standards for sulfuric or nitric oxides, ozone and so on, have been set only just below the level that already causes a health hazard, and these standards are exceeded once in a while. Otherwise, traffic would have to be forbidden and many industrial plants, especially power stations using coal, would have to stop working whenever a low-temperature inversion occurred. Environmental radioactivity does not represent a likely health risk in Finland unless a nuclear war breaks out. Air pollutants, on the contrary, are a real and almost daily health risk that should be carefully considered when decisions about our energy production are being made. In spite of what happened at Chernobyl, global consumption of nuclear power will double by the year 2000, since there are about 140 nuclear power plants presently under construction. It is not likely that another catastrophe like Chernobyl will happen, yet nuclear plant accidents are of course possible, even if their likelihood is diminished by improving reactor safety and even if any eventual damage could be expected to be smaller. If a reactor is hooded by a containment structure, no significant release of radioactive materials should be possible even in case of an accident. However, we must

Leukaemia risks and exposure to ionizing radiations. ASN seminar, Tuesday, June 9, 2015, report

International Nuclear Information System (INIS)

Niel, Jean-Christophe; Samain, Jean-Paul; Colonna, Marc; Maynadie, Marc; Richardson, David; Bey, Pierre; Leuraud, Klervi; Laurier, Dominique; Hemon, Denis; Spycher, Ben; Kosti, Ourania; Bouville, Andre; Grosche, Bernd; Ziegelberger, Gunde; Kesminiene, Ausrele; Clavel, Jacqueline; Smeesters, Patrick; Murith, Christophe

2015-08-01

This seminar aims at proposing a review of present knowledge on leukaemia risks for children and adults associated with ionizing radiations, and at sharing knowledge between experts. After an introduction which outlined the interest of the ASN in research issues, and the importance awarded by the ASN to the variety of points of view, a first session addressed leukaemia and exposures to ionizing radiations. The contributions addressed some general aspects (an overview of leukaemia in France, the different types of adult and child leukaemia), leukaemia and acute exposures to ionizing radiations (ionizing radiation and leukaemia among Japanese bomb survivors, risks of leukaemia after radiotherapy), leukaemia and chronic exposures to ionizing radiations (assessment of epidemiological studies for adult chronic exposures). The second session addressed childhood leukaemia and ionizing radiations. The contributions of this second session more particularly addressed the following topics: childhood leukaemia and natural radioactivity (French studies, synthesis of international studies and a new Swiss study), childhood leukaemia and proximity of nuclear base installations (assessment of national and international studies, analysis of cancer risks in populations near nuclear facilities in the US, calculation of dose at the medulla as example of dosimetry of ionizing radiations and leukaemia, conclusions of the 2012 MELODI workshop), childhood leukaemia and scanner (recent results and perspectives), childhood leukaemia and other risk factors (etiology of childhood leukaemia - presentation of French studies initiated by the INSERM, and presentation of studies initiated by BfS)

Radiation. Doses, effect, risk

International Nuclear Information System (INIS)

Vapirev, E.; Todorov, P.

1994-12-01

This book outlines in a popular form the topic of ionizing radiation impacts on living organisms. It contains data gathered by ICRP for a period of 35 years. The essential dosimetry terms and units are presented. Natural and artificial sources of ionizing radiation are described. Possible biological radiation effects and diseases as a consequence of external and internal irradiation at normal and accidental conditions are considered. An assessment of genetic risk for human populations is presented and the concept of 'acceptable risk' is discussed

Effect Of Oligomeric Enteral Nutrition On Symptoms Of Acute Radiation Enteritis

International Nuclear Information System (INIS)

Dubinsky, P.

2008-01-01

Radiotherapy of abdominal and pelvic tumours is frequently associated with acute radiation enteritis. Predominant symptoms include diarrhea, watery stools, abdominal pain, nausea and vomiting. There are very few effective interventions available for this condition. Enteral oligomeric nutrition has been used in bowel diseases with functional failure similar to radiation enteritis. The aim of presented work was to observe occurrence of symptoms of radiation enteritis in patients undergoing abdominal or pelvic radiotherapy. Apart from diet and pharmacological therapy, oral oligomeric enteral nutrition (Peptisorb Powder Nutricia) at the dose of 1000 - 2000 ml per day was administered for minimum of 4 days. Planned period of administration was 14 days and longer. Symptoms of radiation enteritis were evaluated at the beginning and in the end of administration. Prevalence of all evaluated symptoms of radiation enteritis was decreased and difference was statistically significant for diarrhea, watery stools, abdominal pain, nausea and vomiting. The use of evaluated oligomeric nutritional support might, in conjunction with pharmacotherapy and diet, alleviate symptoms of acute radiation enteritis and maintain nutritional status of patients. (author)

A suggested approach for deriving risk criteria in radiation protection and land use planning

International Nuclear Information System (INIS)

Cameron, R.F.; Corran, E.R.

1994-01-01

In radiation protection, tolerability has been determined by setting a limit on the dose received recognizing that there is an unavoidable background level of radiation to which we are all exposed. This dose is sometimes associated with a cancer fatality coefficient to convert the dose to a probability of fatality, but it is recognised that fatality is not immediate but arises (if at all) many years after the exposure. In other hazardous industry, tolerability is based on satisfying annual fatality risk limits for the number of immediate fatalities. These limits vary with the type of land use proposed. This raises the questions of how such risks should be compared and, in particular, whether there is a basis for common risk measures to be derived. Unless this can be done, inappropriate comparisons will continue to be made. In this paper, a method is suggested for deriving measures of risk to individuals and to communities, both for activities involving radiation exposure and for accidents with other hazardous materials. The method is based on taking account of the difference between continuing releases and accidental transient releases. It is argued that the continuous releases, the lifetime risk is the most appropriate parameter both for radiation and hazardous material exposure. For accident situations both individual and societal risk curves can be drawn which take account of the difference between acute and latent fatalities. Some problems associated with societal risk curves are discussed and suggestions for their use given. 11 refs., 3 figs

Assessment of risk from radiation sources

International Nuclear Information System (INIS)

Subbaratnam, T.; Madhvanath, U.; Somasundaram, S.

1976-01-01

Assessment of risk from exposure to ionizing radiations from man-made radiation sources and nuclear installations has to be viewed from three aspects, namely, dose-effect relationship (genetic and somatic) for humans, calculation of doses or dose-commitments to population groups, assessment of risk to radiation workers and the population at large from the current levels of exposure from nuclear industry and comparison of risk estimates with other industries in a modern society. These aspects are discussed in brief. On the basis of available data, it is shown that estimated incidence of genetic diseases and cancers due to exposure of population to radiation from nuclear industry is negligible in comparison with their natural incidence, and radiation risks to the workers in nuclear industry are much lower than the risks in other occupations. (M.G.B.)

Ileal perforation induced by acute radiation injury under gefitinib treatment

International Nuclear Information System (INIS)

Muraoka, Takayuki; Tsukuda, Kazunori; Toyooka, Shinichi

2011-01-01

Enteritis is one of the side effects of radiotherapy to the abdominal cavity. Radiation enteritis involves damage to mucous membranes in the acute phase and to stromal tissues in the late phase. Perforation of the intestine tends to occur in the late phase, and rarely in the acute phase. However, we describe here a case of intestinal perforation occurring in the acute phase after irradiation in a patient who received gefitinib treatment. Gefitinib, one of the epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), is widely used to treat non-small cell lung cancer (NSCLC) patients, but is simultaneously known to inhibit wound healing. We suspect that gefitinib may affect regeneration of the small intestinal mucosa injured by irradiation. A 76-year-old woman had NSCLC with metastases to the 5th lumbar, sacral, and right iliac bones. To control the pain from bone metastasis, anterior-posterior opposing portal irradiation (total 35 Gy) was started, and was completed over 22 days. On day 25 after starting radiotherapy, the patient began to take gefitinib. On day 35, she presented with acute peritonitis, and an emergency laparotomy was performed. The terminal ileum was affected by radiation enteritis and there were two pin-hole perforations. In the surgical specimen, no cancerous lesions were detected, and immunohistochemical staining of phosphorylated EGFR (pEGFR) was negative. pEGFR has an important role in mucous membrane repair after irradiation. Intestinal perforation in the acute phase of radiation enteritis may be associated with impaired mucosal repair mechanisms due to the use of an EGFR-TKI such as gefitinib, as evidenced by the absence of pEGFR. (author)

Assessment of genetic risk for human exposure to radiation

International Nuclear Information System (INIS)

Sevcenko, V.A.; Rubanovic, A.V.

2002-01-01

Full text: The methodology of assessing the genetic risk of radiation exposure is based on the concept of 'hitting the target' in development of which N.V. Timofeeff-Ressovsky has played and important role. To predict genetic risk posed by irradiation, the U N Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has worked out direct and indirect methods of assessment, extrapolation, integral and palpitation criteria of risk analysis that together permit calculating the risk from human exposure on the basis of data obtained for mice. Based on the reports of UNSCEAR for the period from 1958 to 2001 the paper presents a retrospective analysis of the use of direct methods and the doubling dose method for quantitative determination of the genetic risk of human exposure expressed as different hereditary diseases. As early as 1962 UNSCEAR estimated the doubling dose (a dose causing as many mutations as those occurring spontaneously during one generation) at 1 Gy for cases of exposure to ionizing radiations with low LET at a low dose rate and this value was confirmed in the next UNSCEAR reports up to now. For cases of acute irradiation the doubling dose was estimated at 0,3-0,4 Gy for the period under review. The paper considers the evolution of the concepts of human natural hereditary variability which is a basis for assessing the risk of exposure by the doubling dose method. The level of human natural genetic variability per 1 000 000 newborns is estimated at 738 000 hereditary diseases including mendelian, chromosomal and multifactorial ones. The greatest difficulties in assessing the doubling dose value were found to occur in the case of multifactorial diseases the pheno typical expression of which depends on mutational events in polygenic systems and on numerous environmental factors. The introduction in calculations of the potential recoverability correction factor (RPCF) made it possible to assess the genetic risk taking into account this class of

Perception of risk from radiation

International Nuclear Information System (INIS)

Slovic, P.

1996-01-01

Perceptions of risk from radiation have been studied systematically for about 20 years. This paper summarises the key findings and conclusions from this research with regard to the nature of risk perceptions, the impacts of these perceptions, and the need for communication about radiological hazards. Perhaps the most important generalisation from research in this area is that there is no uniform or consistent perception of radiation risks. Public perception and acceptance is determined by the context in which the radiation is used -and the very different reactions to different uses provide insight into the nature of perception and the determinants of acceptable risk. (author)

Radiation therapy treatment of acute refractory renal allograft rejection

International Nuclear Information System (INIS)

Godinez, J.; Thisted, R.A.; Woodle, E.S.; Thistlethwaite, J.R.; Powers, C.; Haraf, D.

1996-01-01

radiation treatment (median 4, range 1-22), number of transplants (one transplant in 77 %), and concomitant immunosuppressive therapy. Independent factors by the Cox regression model were: Sex (P=0.005), Creatinine levels (P=0.000), HLA-DR (P=0.05), PRA-Max > 70% (P=0.014). Each factor was scored using the integral coefficients to generate four different groups. The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year and 36% at 5 years. The Kaplan-Meier survival analyzed by groups seems to produce an interpretable separation of the risk factors for graft loss. The number of rejections of pre-RT range from 1-6 (median 2) and post-RT range from 0-3 (median 0). Conclusions: Our experience indicates that radiation therapy provides effective treatment for acute refractory renal allograft rejection. The response to radiation therapy in patients treated with acute refractory renal graft rejection can be predicted by a new scoring system

Chernobyl 1996. New materials concerning acute radiation syndrome around Chernobyl

International Nuclear Information System (INIS)

Lupandin, Vladimir M.

2016-01-01

In 1996 we have succeeded in getting reliable data on radiation situation in the Khoiniki district. These were data of Civil Defence Headquarters of the Khoiniki district, remaining in private notes of the Chief of the Headquarters. Including the other data or materials, radiation syndromes in particular the acute are described. (J.P.N.)

Studies of adaptive response and mutation induction in MCF-10A cells following exposure to chronic or acute ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Manesh, Sara Shakeri; Sangsuwan, Traimate; Wojcik, Andrzej; Haghdoost, Siamak, E-mail: Siamak.haghdoost@su.se

2015-10-15

Highlights: • 50 mGy at 1.4 mGy/h induces adaptive response in MCF-10A at mutation level. • Low dose rate γ-radiation does not induce adaptive response at survival level. • Overall, a dose rate effect is absent at the level of mutation in MCF-10A cells. - Abstract: A phenomenon in which exposure to a low adapting dose of radiation makes cells more resistant to the effects of a subsequent high dose exposure is termed radio-adaptive response. Adaptive response could hypothetically reduce the risk of late adverse effects of chronic or acute radiation exposures in humans. Understanding the underlying mechanisms of such responses is of relevance for radiation protection as well as for the clinical applications of radiation in medicine. However, due to the variability of responses depending on the model system and radiation condition, there is a need to further study under what conditions adaptive response can be induced. In this study, we analyzed if there is a dose rate dependence for the adapting dose, assuming that the adapting dose induces DNA response/repair pathways that are dose rate dependent. MCF-10A cells were exposed to a 50 mGy adapting dose administered acutely (0.40 Gy/min) or chronically (1.4 mGy/h or 4.1 mGy/h) and then irradiated by high acute challenging doses. The endpoints of study include clonogenic cell survival and mutation frequency at X-linked hprt locus. In another series of experiment, cells were exposed to 100 mGy and 1 Gy at different dose rates (acutely and chronically) and then the mutation frequencies were studied. Adaptive response was absent at the level of clonogenic survival. The mutation frequencies were significantly decreased in the cells pre-exposed to 50 mGy at 1.4 mGy/h followed by 1 Gy acute exposure as challenging dose. Importantly, at single dose exposures (1 Gy or 100 mGy), no differences at the level of mutation were found comparing different dose rates.

Risk management of radiation therapy. Survey by north Japan radiation therapy oncology group

International Nuclear Information System (INIS)

Aoki, Masahiko; Abe, Yoshinao; Yamada, Shogo; Hareyama, Masato; Nakamura, Ryuji; Sugita, Tadashi; Miyano, Takashi

2004-01-01

A North Japan Radiation Oncology Group (NJRTOG) survey was carried out to disclose the risk management of radiation therapy. During April 2002, we sent questionnaires to radiation therapy facilities in northern Japan. There were 31 replies from 27 facilities. Many incidents and accidents were reported, including old cases. Although 60% of facilities had a risk management manual and/or risk manager, only 20% had risk management manuals for radiation therapy. Eighty five percent of radiation oncologists thought that incidents may be due to a lack of manpower. Ninety percent of radiation oncologists want to know the type of cases happened in other facilities. The risk management system is still insufficient for radiation therapy. We hope that our data will be a great help to develop risk management strategies for radiation therapy for all radiation oncologists in Japan. (author)

Radiation risk in space exploration

International Nuclear Information System (INIS)

Schimmerling, W.; Wilson, J.W.; Cucinotta, F.; Kim, M.H.Y.

1997-01-01

Humans living and working in space are exposed to energetic charged particle radiation due to galactic cosmic rays and solar particle emissions. In order to keep the risk due to radiation exposure of astronauts below acceptable levels, the physical interaction of these particles with space structures and the biological consequences for crew members need to be understood. Such knowledge is, to a large extent, very sparse when it is available at all. Radiation limits established for space radiation protection purposes are based on extrapolation of risk from Japanese survivor data, and have been found to have large uncertainties. In space, attempting to account for large uncertainties by worst-case design results in excessive costs and accurate risk prediction is essential. It is best developed at ground-based laboratories, using particle accelerator beams to simulate individual components of space radiation. Development of mechanistic models of the action of space radiation is expected to lead to the required improvements in the accuracy of predictions, to optimization of space structures for radiation protection and, eventually, to the development of biological methods of prevention and intervention against radiation injury. (author)

Modification of Acute Radiation Response in Different Demographic Age Groups

Science.gov (United States)

2017-10-25

greater radiosensitivity. Other studies provided further mechanistic insight into the observed age effect of radiation responses. For example ...DISTRIBUTION A. Approved for public release; distribution is unlimited. October 2017 HDTRA1-14-0003; 0005 Prepared by: Applied ... Research Associates, Inc. 801 N. Quincy Street Suite 700 Arlington, VA 22203 Modification of Acute Radiation Response in Different Demographic Age

Macrophage expression in acute radiation colitis in rats

International Nuclear Information System (INIS)

Tadami, Tokuma; Shichijo, Kazuko; Matsuu, Mutsumi; Niino, Daisuke; Nakayama, Toshiyuki; Nakashima, Masahiro; Sekine, Ichiro

2003-01-01

Although radiation therapy is important in the treatment of tumors in pelvic and abdominal region, it may cause radiation injury as a side effect. But there is no effective way of preventing or curing the damages. The mechanism of acute radiation colitis has not been elucidated yet. Our previous reports have revealed that X-ray irradiation induce apoptosis of epithelial stem cells in colon. Then a hypothesis of the radiation colitis can be put forward, DNA damage by irradiation, apoptosis of mucosal epithelial stem cells and degeneration of epithelial gland structure, macrophages phagocyte the debris, being activated and secreting various inflammatory cytokines, infiltration of inflammatory cells. Several recent reports show that macrophages may play an important role in the process of inflammatory bowel diseases such ulcerative colitis or Crohn's disease. We studied radiation colitis using rat animal models. Male Wister rats were irradiated by a single fraction dose of 22.5 Gy X-ray at laparotomy, shielding except for an approximately 2.5 cm length of rectum. Histological changes and macrophage accumulation in the rectum mucosa were evaluated by immunohistochemistry and western blot method with the specimens which were taken on the 1, 2, 3, 4, 5, 6, 7, 10, and 14th day after irradiation. Severe macrophage accumulation in the lamina propria of the rectum was observed on the 5th day. At the same time, severe destruction of mucosal structure and inflammatory cells infiltration were also observed. Based on the potent pro-inflammatory cytokine producing effects of macrophage in rat and the increased expression in inflammatory bowel disease patients, speculate that intervention in the macrophage-cytokine network could form a future target for the treatment of acute radiation colitis. (author)

Risk of occupational exposure to ionizing radiation among medical workers in Canada

International Nuclear Information System (INIS)

Zielinski, Jan M.; Band, Pierre R.; Garner, Michael J.; Krewski, Daniel; Shilnikova, Natalia S.; Jiang, Huixia; Ashmore, Patrick J.; Sont, Willem N.; Fair, Martha E.; Letourneau, Ernest G.; Semenciw, Robert

2010-01-01

Medical workers are exposed to chronic low dose ionizing radiation from a variety of sources. Potential cancer risks associated with ionizing radiation exposures have been derived from cohorts experiencing acute high intensity exposure, most notably the Japanese atomic bomb survivors. Since such extrapolations are subject to uncertainty, direct information on the risk associated with chronic low dose occupational exposure to ionizing radiation is needed. We examined possible associations with cancer incidence and mortality in a cohort of medical workers ascertained by the National Dose Registry of Canada (NDR). Data from the NDR were used to assess the exposure to ionizing radiation incurred between 1951 to 1987 inclusive in a cohort of 67,562 subjects classified as medical workers. Standardized mortality (SMRs) and incidence (SIRs) ratios were ascertained by linking NDR data with the data maintained by Statistics Canada in the Canadian Mortality and in the Canadian Cancer Incidence Databases respectively. Dosimetry information was obtained from the National Dosimetry Services of the Radiation Protection Bureau of Health Canada. There were 23,580 male and 43,982 female medical workers in the cohort. During the follow-up period, 1309 incident cases of cancer (509 in males, 800 in females) and 1,325 deaths (823 in males, 502 in females) were observed. Mortality from cancer and non-cancer causes was generally below expected compared to the Canadian population. Thyroid cancer incidence was significantly elevated in both males and females, with a combined SIR of 1.74 and 90% confidence interval (90% CI: 1.40-2.10). Our result of an increased risk of thyroid cancer among medical workers occupationally exposed to ionizing radiation confirms previous reports. Over the last 50 years, radiation protection measures have been effective in reducing occupational exposures of medical workers to ionizing radiation to current very low levels. (author)

Risk profile in young patients with acute myocardial infarction

International Nuclear Information System (INIS)

Safdar, M.H.K.; Fazal, I.; Ejaz, A.; Awan, Z.I.

2010-01-01

The objective of this study was to determine the frequency of risk factors in young patients with acute myocardial infarction and thus with ischemic heart disease (IHD), aged 20 to 40 years, in our population. All patients who fulfilled the inclusion criteria who presented to emergency reception of the hospital with a diagnosis of Acute MI were included. The patients were admitted to coronary care unit (CCU) and were managed for Acute myocardial infarction (MI). Their detailed history was then taken including symptoms at presentation and their risk factors were assessed with the help of history and laboratory investigations. A total of 137 patients were included during the study period. Mean age was 36 years (SD=3.67). Majority of patients were males. Smoking was the major risk factor (64.2%) followed by family history of IHD (30.7%). Most frequent risk factor for Acute myocardial infarction (MI) at young age is smoking followed by family history. (author)

Generalized indices for radiation risk analysis

International Nuclear Information System (INIS)

Bykov, A.A.; Demin, V.F.

1989-01-01

A new approach to ensuring nuclear safety has begun forming since the early eighties. The approach based on the probabilistic safety analysis, the principles of acceptable risk, the optimization of safety measures, etc. has forced a complex of adequate quantitative methods of assessment, safety analysis and risk management to be developed. The method of radiation risk assessment and analysis hold a prominent place in the complex. National and international research and regulatory organizations ICRP, IAEA, WHO, UNSCEAR, OECD/NEA have given much attention to the development of the conceptual and methodological basis of those methods. Some resolutions of the National Commission of Radiological Protection (NCRP) and the Problem Commission on Radiation Hygiene of the USSR Ministry of Health should be also noted. Both CBA (cost benefit analysis) and other methods of radiation risk analysis and safety management use a system of natural and socio-economic indices characterizing the radiation risk or damage. There exist a number of problems associated with the introduction, justification and use of these indices. For example, the price, a, of radiation damage, or collective dose unit, is a noteworthy index. The difficulties in its qualitative and quantitative determination are still an obstacle for a wide application of CBA to the radiation risk analysis and management. During recent 10-15 years these problems have been a subject of consideration for many authors. The present paper also considers the issues of the qualitative and quantitative justification of the indices of radiation risk analysis

Explanation of application standards of hematopoietic stimulating factors in the treatment of acute radiation sickness

International Nuclear Information System (INIS)

Xing Zhiwei; Jiang Enhai; Wang Guilin; Luo Qingliang

2012-01-01

Occupational standard of the Ministry of health-Application Standards of Hematopoietic Stimulating Factors in the Treatment of Acute Radiation Sickness has been completed as a draft standard. Based on the wide study and analysis of related animal experimental literature about hematopoietic stimulating factor in the treatment of acute radiation sickness and domestic and foreign clinical reports about application of hematopoietic stimulating factor in radiation accidents in the past decade, the standard was enacted according to the suggestions of International Atomic Energy Agency and the United States Strategic National Stockpile Radiation Working Group and European countries about the application of hematopoietic stimulating factor. It is mainly used for nuclear accident emergency and the treatment of the bone marrow form of acute radiation sickness caused by radiation accidents. It also applies to other hematopoietic failure diseases. In order to implement this standard correctly, the relevant contents of the standard were interpreted in this article. (authors)

Clinico-morphological characteristics of reparation of acute radiation ulcer

International Nuclear Information System (INIS)

Petrik, V.D.; Yakovleva, N.D.; Bardychev, M.S.

1979-01-01

The mechanism of reparative processes under the effect of various drugs was studied in experimental acute radiation ulcer of rats. It was established that at the stage of marked exudative-necrotic processes the use of antiinflammatory and antiexudative substances (bariz, dimethylsulfoxyde) led to normalization of the microcirculation that reduced the time of radiation ulcer healing. The use of anabolic steroids (retabolil) intensified metabolism that also produced a favourable effect on the reparative processes

Hematological observations on two cases of acute radiation syndrome

International Nuclear Information System (INIS)

Jiang Benrong; Wang Guilin; Huang Shimin

1990-01-01

The hematological changes of two cases of acute radiation syndrome were observed. The physical doses of patients Liang and Yan were 3.5 Gy and 2.6 Gy respectively. According to the changes in WBC and platelet counts and the absolute count of lymphocytes and in comparison with the hematological data of the victims of Y-12 accident in USA in 1958 and those of previous accidents in China, Liang suffered from a moderate or moderate to severe degree, and Yan suffered from a moderate or moderate mild degree of hemopoietic form of acute radiation syndrome. This estimation was consistent with their clinical course and physical doses. Some blood cells appeared in the cytoplasm of megakaryocytes in bone marrow smears of those two cases. The mechanism of this phenomenon is discussed and its clinical significance remains to be studied

Radioprotective effect of Rapana thomasiana hemocyanin in gamma induced acute radiation syndrome

International Nuclear Information System (INIS)

Kindekov, Ivan; Vassilieva, Vladimir; Aljakova, Mitko; Mileva, Milka; Krastev, Dimo; Raynova, Yuliana; Idakieva, Krassimira; Doumanov, Lyuba

2014-01-01

The radioprotective effect of Rapana thomasiana hemocyanin (RtH) against radiation-induced injuries (stomach ulcers, survival time and endogenous haemopoiesis) and post-radiation recovery was investigated in male albino mice (C3H strain). Radiation course was in a dose of 7.5 Gy (LD 100/30 - dose that kills 100% of the mice at 30 days) from "1"3"7Cs with a dose of 2.05 Gy/ min. Radiation injuries were manifested by inducing 2 hematopoietic form of acute radiation syndrome. RtH was administered intraperitoneally in a single dose of 50, 100, 150 and 200 mg/kg body weight (b. w.) once a day for five consecutive days before irradiation. The results obtained showed that radiation exposure led to (1) 100% mortality rate, (2) ulceration in the stomach mucosa and (3) decrease formation of spleen colonies as a marker of endogenous haemopoiesis. Administration of RtH at a dose of 200 mg/kg provided better protection against radiation-induced stomach ulceration, mitigated the lethal effects of radiation exposure and recovered endogenous haemopoiesis versus irradiated but not supplemented mice. It could be expected that RtH will find a use in mitigating radiation induced injury and enhanced radiorecovery. Keywords: Rapana thomasiana hemocyanin; acute radiation syndrome; radioprotective effect; spleen colony assay; stomach ulcerations

The impact on radiation risk estimates of effect modifiers and confounders

International Nuclear Information System (INIS)

Sharp, G.B.; Cologne, J.B.; Pierce, D.A.; Tokuoka, S.

2003-01-01

We have conducted studies of the joint effects of radiation with other risk factors for liver, lung, and breast cancer in the cohort of Japanese survivors of the 1945 atomic bombings. Based on follow-up of 45,113 subjects from 1958 through 1994, of whom 592 developed lung cancer, we found the effects of smoking and radiation to be significantly non-multiplicative and consistent with additivity. Adjustment for smoking reduced the female:male ratio of radiation risk estimates for lung cancer in this cohort from 5.8 to 1.6, a ratio more similar to that for all solid cancers. We conducted cross sectional and case control studies within the A-bomb survivor cohort to assess the joint effects of radiation with hepatitis B virus (HBV) and C virus (HCV) infections on the etiology of liver cirrhosis and hepatocellular carcinoma (HCC). Our study of 268 pathologist-confirmed cirrhosis cases and 843 subjects without cirrhosis, found no relationship between A-bomb radiation and cirrhosis after adjustment for viral hepatitis. In terms of HCC, our study of 238 pathologist-confirmed cases and 894 controls showed super-multiplicative interaction between radiation and HCV infections. Our results suggest that while chronic radiation exposure acts as a complete carcinogen for HCC, acute irradiation may act in concert with an agent such as HCV that is associated with liver cell proliferation. Studies in progress of the joint effects of radiation with insulin-like growth factor 1 (IGF-1) and IGF Binding Protein 3 (IGFBP-3), and total estradiol on the etiology of breast cancer, a particularly radiogenic tumor, will also be discussed

Residual insufficiency of hematopoiesis after acute or chronic exposure to gamma radiation or neutrons

International Nuclear Information System (INIS)

Wangenheim, K.H. v.; Peterson, H.P.; Feinendegen, L.E.

1983-01-01

Recovery of the stem cell quality is possible after acute exposure to 500 rad γ radiation up to a period of 6 months. Beyond this data, a significant residual damage remains. The same applies to quantitative stem cell recovery. Chronic γ exposure leads to less radiation damage than acute exposure. After a total accumulation of 500 rad, the proliferation factors after chronic exposure were, on an average 20% higher than after acute radiation exposure. 6 MeV neutron exposure reduced the stem cell quality and stem cell count much more efficiently than γ exposure. The relative biological effect of neutrons is at least 2.5 times as high as the γ effect, both for the stem cell count and the stem cell quality. (orig.) [de

Ecological effects of various toxic agents on the aquatic microcosm in comparison with acute ionizing radiation

International Nuclear Information System (INIS)

Fuma, S.; Ishii, N.; Takeda, H.; Miyamoto, K.; Yanagisawa, K.; Ichimasa, Y.; Saito, M.; Kawabata, Z.; Polikarpov, G.G.

2003-01-01

The purpose of this study was an evaluation of the effect levels of various toxic agents compared with acute doses of ionizing radiation for the experimental model ecosystem, i.e., microcosm mimicking aquatic microbial communities. For this purpose, the authors used the microcosm consisting of populations of the flagellate alga Euglena gracilis as a producer, the ciliate protozoan Tetrahymena thermophila as a consumer and the bacterium Escherichia coli as a decomposer. Effects of aluminum and copper on the microcosm were investigated in this study, while effects of γ-rays, ultraviolet radiation, acidification, manganese, nickel and gadolinium were reported in previous studies. The microcosm could detect not only the direct effects of these agents but also the community-level effects due to the interspecies interactions or the interactions between organisms and toxic agents. The authors evaluated doses or concentrations of each toxic agent which had the following effects on the microcosm: (1) no effects; (2) recognizable effects, i.e., decrease or increase in the cell densities of at least one species; (3) severe effects, i.e., extinction of one or two species; and (4) destructive effects, i.e., extinction of all species. The resulting effects data will contribute to an ecological risk assessment of the toxic agents compared with acute doses of ionizing radiation

Radiation risk of diagnostical procedures

International Nuclear Information System (INIS)

Pohlit, W.

1986-01-01

The environmental radiation burden of man in Germany is about 1 mGy (Milligray) per year. This is, of course, also valid for children. Due to diagnostical procedures this burden is increased to about 1.3 mGy. The question arises wether this can be neglected, or important consequences have to be drawn. To give a clear answer, the action of ionizing radiation in living cells and in organisms is explained in detail. Many of the radiation actions at the DNA can soon be repaired by the cell, if the radiation dose was small. Some damage, however will remain irreparable for the cell and consequently leads to cell death, to mutations or to cell transformation. The number of these lesion increases or decreases linearily with radiation dose. Therefore, it must be expected that the risk of tumour induction is increased to above the normal background even by the smallest doses. This small but not negligible risk has to be compared with other risks of civilization or with other medical risks. But also the benefit and the efficacy of diagnostic procedures have to be considered. (orig./HSCH) [de

Prostate hypofractionated radiation therapy with injection of hyaluronic acid: acute toxicities in a phase 2 study.

Science.gov (United States)

Chapet, Olivier; Decullier, Evelyne; Bin, Sylvie; Faix, Antoine; Ruffion, Alain; Jalade, Patrice; Fenoglietto, Pascal; Udrescu, Corina; Enachescu, Ciprian; Azria, David

2015-03-15

Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity. Copyright © 2015 Elsevier Inc. All rights reserved.

Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

International Nuclear Information System (INIS)

Chapet, Olivier; Decullier, Evelyne; Bin, Sylvie; Faix, Antoine; Ruffion, Alain; Jalade, Patrice; Fenoglietto, Pascal; Udrescu, Corina; Enachescu, Ciprian; Azria, David

2015-01-01

Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity

Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

Energy Technology Data Exchange (ETDEWEB)

Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); EMR3738, Université Lyon 1, Lyon (France); Decullier, Evelyne; Bin, Sylvie [Pole Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon (France); Université Lyon 1, Lyon (France); EA SIS, Université de Lyon, Lyon (France); Faix, Antoine [Department of Urology, Clinique Beausoleil, Montpellier (France); Ruffion, Alain [Université Lyon 1, Lyon (France); Department of Urology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Jalade, Patrice [Department of Medical Physics, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Fenoglietto, Pascal [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France); Udrescu, Corina; Enachescu, Ciprian [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Azria, David [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France)

2015-03-15

Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity.

Subacute radiation dermatitis: a histologic imitator of acute cutaneous graft-versus-host disease

International Nuclear Information System (INIS)

LeBoit, P.E.

1989-01-01

The histopathologic changes of radiation dermatitis have been classified either as early effects (necrotic keratinocytes, fibrin thrombi, and hemorrhage) or as late effects (vacuolar changes at the dermal-epidermal junction, atypical radiation fibroblasts, and fibrosis). Two patients, one exposed to radiation therapeutically and one accidentally, are described. Skin biopsy specimens showed an interface dermatitis characterized by numerous dyskeratotic epidermal cells with lymphocytes in close apposition (satellite cell necrosis); that is, the epidermal changes were similar to those in acute graft-versus-host disease. Because recipients of bone marrow transplants frequently receive total body irradiation as part of their preparatory regimen, the ability of radiation to cause persistent epidermal changes similar to those in acute graft-versus-host disease could complicate the interpretation of posttransplant skin biopsy specimens

Radiation in space: risk estimates

International Nuclear Information System (INIS)

Fry, R.J.M.

2002-01-01

The complexity of radiation environments in space makes estimation of risks more difficult than for the protection of terrestrial population. In deep space the duration of the mission, position of the solar cycle, number and size of solar particle events (SPE) and the spacecraft shielding are the major determinants of risk. In low-earth orbit missions there are the added factors of altitude and orbital inclination. Different radiation qualities such as protons and heavy ions and secondary radiations inside the spacecraft such as neutrons of various energies, have to be considered. Radiation dose rates in space are low except for short periods during very large SPEs. Risk estimation for space activities is based on the human experience of exposure to gamma rays and to a lesser extent X rays. The doses of protons, heavy ions and neutrons are adjusted to take into account the relative biological effectiveness (RBE) of the different radiation types and thus derive equivalent doses. RBE values and factors to adjust for the effect of dose rate have to be obtained from experimental data. The influence of age and gender on the cancer risk is estimated from the data from atomic bomb survivors. Because of the large number of variables the uncertainties in the probability of the effects are large. Information needed to improve the risk estimates includes: (1) risk of cancer induction by protons, heavy ions and neutrons; (2) influence of dose rate and protraction, particularly on potential tissue effects such as reduced fertility and cataracts; and (3) possible effects of heavy ions on the central nervous system. Risk cannot be eliminated and thus there must be a consensus on what level of risk is acceptable. (author)

Methods for assessing the extent of acute radiation injury

International Nuclear Information System (INIS)

Fliedner, T.M.

1996-01-01

Previous radiation accidents have shown that the medical management of exposed persons cannot be performed without the use of 'biological indicators' of effect and of repair. For the clinical management of a patient with the acute radiation syndrome, it is essential to obtain information on the subjective symptomatology as well as on laboratory parameters, especially during the first 3 to 6 days after exposure. The medical doctor responsible for the clinical care of patients has to rely on the use of what has been described as 'sequential diagnosis'. This approach consists essentially of the determination of a limited number of parameters as a function of time. From the analysis of the pattern of the determined and evaluated signs and symptoms in the first hours and days, one is able to characterize patients according to type and severity of symptomatology. This has been clearly demonstrated in the Moscow - Ulm Radiation Accident Database (MURAD) developed in a collaborative project between the Institute of Biophysics in Moscow and the Department of Clinical Physiology and Occupational Medicine of the University of Ulm. On the basis of the radiation accident clinical response pattern observed early after irradiation, one is able to develop a first approach for therapeutic strategies. It is the purpose of this contribution to outline the diagnostic and prognostic significance of blood cell changes and to discuss the following problem areas: significance and elements of a sequential diagnosis; significance of blood lymphocytes for radiation accident diagnosis; significance of blood granulocyte changes for the prognosis of the acute radiation syndrome; analysis of granulocyte changes by means of regulated system models; utilization of indicators of response and repair for planning therapeutic options

Immuno-therapy of Acute Radiation Syndromes : Extracorporeal Immuno-Lympho-Plasmo-Sorption.

Science.gov (United States)

Popov, Dmitri; Maliev, Slava

Methods Results Summary and conclusions Introduction: Existing Medical Management of the Acute Radiation Syndromes (ARS) does not include methods of specific immunotherapy and active detoxication. Though the Acute Radiation Syndromes were defined as an acute toxic poisonous with development of pathological processes: Systemic Inflammatory Response Syndrome (SIRS), Toxic Multiple Organ Injury (TMOI), Toxic Multiple Organ Dysfunction Syndrome(TMODS), Toxic Multiple Organ Failure (TMOF). Radiation Toxins of SRD Group play an important role as the trigger mechanisms in development of the ARS clinical symptoms. Methods: Immuno-Lympho-Plasmo-Sorption is a type of Immuno-therapy which includes prin-ciples of immunochromato-graphy, plasmopheresis, and hemodialysis. Specific Antiradiation Antitoxic Antibodies are the active pharmacological agents of immunotherapy . Antiradia-tion Antitoxic Antibodies bind selectively to Radiation Neurotoxins, Cytotoxins, Hematotox-ins and neutralize their toxic activity. We have developed the highly sensitive method and system for extracorporeal-immune-lypmh-plasmo-sorption with antigen-specific IgG which is clinically important for treatment of the toxic and immunologic phases of the ARS. The method of extracorporeal-immune-lypmh-plasmo-sorption includes Antiradiation Antitoxic Antibodies (AAA) immobilized on microporous polymeric membranes with a pore size that is capable to provide diffusion of blood-lymph plasma. Plasma of blood or lymph of irradiated mammals contains Radiation Toxins (RT) that have toxic and antigenic properties. Radiation Toxins are Antigen-specific to Antitoxic blocking antibodies (Immunoglobulin G). Plasma diffuses through membranes with immobilized AAA and AA-antibodies bind to the polysaccharide chain of tox-ins molecules and complexes of AAA-RT that are captured on membrane surfaces. RT were removed from plasma. Re-transfusion of plasma of blood and lymph had been provided. We show a statistical significant

Radiation exposure and risk of death

International Nuclear Information System (INIS)

Hongo, Syozo

1979-01-01

By using the risk factor given in ICRP publication 26 and an assumption of linear relationship between risk and dose, death rate and death number which correspond to radiation dose level and collective dose level of Japanese are estimated and they are compared with vital statistics of Japanese in 1975 to get out some ideas about radiation risk relative to the risks of everyday life. (author)

Training loads and injury risk in Australian football—differing acute: chronic workload ratios influence match injury risk

Science.gov (United States)

Carey, David L; Blanch, Peter; Ong, Kok-Leong; Crossley, Kay M; Crow, Justin; Morris, Meg E

2017-01-01

Aims (1) To investigate whether a daily acute:chronic workload ratio informs injury risk in Australian football players; (2) to identify which combination of workload variable, acute and chronic time window best explains injury likelihood. Methods Workload and injury data were collected from 53 athletes over 2 seasons in a professional Australian football club. Acute:chronic workload ratios were calculated daily for each athlete, and modelled against non-contact injury likelihood using a quadratic relationship. 6 workload variables, 8 acute time windows (2–9 days) and 7 chronic time windows (14–35 days) were considered (336 combinations). Each parameter combination was compared for injury likelihood fit (using R2). Results The ratio of moderate speed running workload (18–24 km/h) in the previous 3 days (acute time window) compared with the previous 21 days (chronic time window) best explained the injury likelihood in matches (R2=0.79) and in the immediate 2 or 5 days following matches (R2=0.76–0.82). The 3:21 acute:chronic workload ratio discriminated between high-risk and low-risk athletes (relative risk=1.98–2.43). Using the previous 6 days to calculate the acute workload time window yielded similar results. The choice of acute time window significantly influenced model performance and appeared to reflect the competition and training schedule. Conclusions Daily workload ratios can inform injury risk in Australian football. Clinicians and conditioning coaches should consider the sport-specific schedule of competition and training when choosing acute and chronic time windows. For Australian football, the ratio of moderate speed running in a 3-day or 6-day acute time window and a 21-day chronic time window best explained injury risk. PMID:27789430

NASA Strategy to Safely Live and Work in the Space Radiation Environment

Science.gov (United States)

Cucinotta, Francis; Wu, Honglu; Corbin, Barbara; Sulzman, Frank; Kreneck, Sam

2007-01-01

This viewgraph document reviews the radiation environment that is a significant potential hazard to NASA's goals for space exploration, of living and working in space. NASA has initiated a Peer reviewed research program that is charged with arriving at an understanding of the space radiation problem. To this end NASA Space Radiation Laboratory (NSRL) was constructed to simulate the harsh cosmic and solar radiation found in space. Another piece of the work was to develop a risk modeling tool that integrates the results from research efforts into models of human risk to reduce uncertainties in predicting risk of carcinogenesis, central nervous system damage, degenerative tissue disease, and acute radiation effects acute radiation effects.

The Increase in Animal Mortality Risk following Exposure to Sparsely Ionizing Radiation Is Not Linear Quadratic with Dose

OpenAIRE

Haley, Benjamin M.; Paunesku, Tatjana; Grdina, David J.; Woloschak, Gayle E.

2015-01-01

Introduction The US government regulates allowable radiation exposures relying, in large part, on the seventh report from the committee to estimate the Biological Effect of Ionizing Radiation (BEIR VII), which estimated that most contemporary exposures- protracted or low-dose, carry 1.5 fold less risk of carcinogenesis and mortality per Gy than acute exposures of atomic bomb survivors. This correction is known as the dose and dose rate effectiveness factor for the life span study of atomic bo...

Estimation of health risks from radiation exposures

International Nuclear Information System (INIS)

Randolph, M.L.

1983-08-01

An informal presentation is given of the cancer and genetic risks from exposures to ionizing radiations. The risks from plausible radiation exposures are shown to be comparable to other commonly encountered risks

Estimation of health risks from radiation exposures

Energy Technology Data Exchange (ETDEWEB)

Randolph, M.L.

1983-08-01

An informal presentation is given of the cancer and genetic risks from exposures to ionizing radiations. The risks from plausible radiation exposures are shown to be comparable to other commonly encountered risks.

A mathematical model for leukemogenesis of radiation-induced acute myeloid leukemia in C3H/He mice

International Nuclear Information System (INIS)

Kai, M.; Ban, N.

2002-01-01

We developed a mathematical model in leukemogenesis of acute myeloid leukemia(AML) in C3H/He mice irradiated. Our previous study indicated that the leukemogenesis of AML was associated with a deletion of chromosome 2 directly induced by acute radiation. We hypothesized that radiation-induced AML needs both inactivation of one allele of a causative gene directly induced by acute radiation and another mutational event at the other allele. We analyzed data using a two-stage stochastic model for carcinogenesis. Model fitting was based on the maximum likelihood method. Our model analysis suggested that a single exposure might induce the long-lasting delayed cell death of radiation-induced initiated cells, and that the incidence of AML may be determined through both radiation-induced initiation and persistent increase of delayed cell death of the initiated cell induced by radiation

Differential diagnosis of the acute abdomen. Pt. 4. Acute abdomen in children

International Nuclear Information System (INIS)

Staatz, Gundula; Schneider, Karl

2010-01-01

The diagnostic work-up of adults with acute abdominal pain has changed significantly within the last decade and computed tomography is often used as the first imaging modality of choice. In pediatric patients with an acute abdomen, ultrasound and abdominal X-rays remain the first line procedures. Because of the radiation risk, computed tomography is only recommended in selected cases and when strongly indicated. This review is the fourth and final part within a series of reviews dealing with the diagnostic strategy in the work-up of patients with an acute abdomen. (orig.)

Acute Toxicity After Image-Guided Intensity Modulated Radiation Therapy Compared to 3D Conformal Radiation Therapy in Prostate Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Wortel, Ruud C.; Incrocci, Luca [Department of Radiation Oncology, Erasmus Medical Center Cancer Institute, Rotterdam (Netherlands); Pos, Floris J.; Lebesque, Joos V.; Witte, Marnix G.; Heide, Uulke A. van der; Herk, Marcel van [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Heemsbergen, Wilma D., E-mail: w.heemsbergen@nki.nl [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands)

2015-03-15

Purpose: Image-guided intensity modulated radiation therapy (IG-IMRT) allows significant dose reductions to organs at risk in prostate cancer patients. However, clinical data identifying the benefits of IG-IMRT in daily practice are scarce. The purpose of this study was to compare dose distributions to organs at risk and acute gastrointestinal (GI) and genitourinary (GU) toxicity levels of patients treated to 78 Gy with either IG-IMRT or 3D-CRT. Methods and Materials: Patients treated with 3D-CRT (n=215) and IG-IMRT (n=260) receiving 78 Gy in 39 fractions within 2 randomized trials were selected. Dose surface histograms of anorectum, anal canal, and bladder were calculated. Identical toxicity questionnaires were distributed at baseline, prior to fraction 20 and 30 and at 90 days after treatment. Radiation Therapy Oncology Group (RTOG) grade ≥1, ≥2, and ≥3 endpoints were derived directly from questionnaires. Univariate and multivariate binary logistic regression analyses were applied. Results: The median volumes receiving 5 to 75 Gy were significantly lower (all P<.001) with IG-IMRT for anorectum, anal canal, and bladder. The mean dose to the anorectum was 34.4 Gy versus 47.3 Gy (P<.001), 23.6 Gy versus 44.6 Gy for the anal canal (P<.001), and 33.1 Gy versus 43.2 Gy for the bladder (P<.001). Significantly lower grade ≥2 toxicity was observed for proctitis, stool frequency ≥6/day, and urinary frequency ≥12/day. IG-IMRT resulted in significantly lower overall RTOG grade ≥2 GI toxicity (29% vs 49%, respectively, P=.002) and overall GU grade ≥2 toxicity (38% vs 48%, respectively, P=.009). Conclusions: A clinically meaningful reduction in dose to organs at risk and acute toxicity levels was observed in IG-IMRT patients, as a result of improved technique and tighter margins. Therefore reduced late toxicity levels can be expected as well; additional research is needed to quantify such reductions.

Leukemia and ionizing radiation revisited

Energy Technology Data Exchange (ETDEWEB)

Cuttler, J.M. [Cuttler & Associates Inc., Vaughan, Ontario (Canada); Welsh, J.S. [Loyola University-Chicago, Dept. or Radiation Oncology, Stritch School of Medicine, Maywood, Illinois (United States)

2016-03-15

A world-wide radiation health scare was created in the late 19508 to stop the testing of atomic bombs and block the development of nuclear energy. In spite of the large amount of evidence that contradicts the cancer predictions, this fear continues. It impairs the use of low radiation doses in medical diagnostic imaging and radiation therapy. This brief article revisits the second of two key studies, which revolutionized radiation protection, and identifies a serious error that was missed. This error in analyzing the leukemia incidence among the 195,000 survivors, in the combined exposed populations of Hiroshima and Nagasaki, invalidates use of the LNT model for assessing the risk of cancer from ionizing radiation. The threshold acute dose for radiation-induced leukemia, based on about 96,800 humans, is identified to be about 50 rem, or 0.5 Sv. It is reasonable to expect that the thresholds for other cancer types are higher than this level. No predictions or hints of excess cancer risk (or any other health risk) should be made for an acute exposure below this value until there is scientific evidence to support the LNT hypothesis. (author)

Developing diagnostic guidelines for the acute radiation syndrome

International Nuclear Information System (INIS)

Densow, D.; Fliedner, T.M.; Kindler, H.

1996-01-01

Diagnostic guidelines seem to be promising for improving medical care. One aspect of a diagnostic guideline for the acute radiation syndrome has been tested against an extensive case history database. Subsequently, the guideline has been optimized for a small set of case histories. The improved performance has been proven by a test against the rest of the case history database

The cognitive profile of children treated with radiation for acute ...

African Journals Online (AJOL)

The cognitive profile of children treated with radiation for acute lymphoblastic leukaemia. ... to disrupt the myelination and integrity of white matter tracts in the brain. ... The current study focused on the assessment of memory and learning, two ...

DNA Double-Strand Break Analysis by {gamma}-H2AX Foci: A Useful Method for Determining the Overreactors to Radiation-Induced Acute Reactions Among Head-and-Neck Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Goutham, Hassan Venkatesh; Mumbrekar, Kamalesh Dattaram [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Vadhiraja, Bejadi Manjunath [Manipal Hospital, Bangalore, Karnataka (India); Fernandes, Donald Jerard; Sharan, Krishna [Department of Radiotherapy and Oncology, Shiridi Sai Baba Cancer Hospital and Research Centre, Kasturba Hospital, Manipal, Karnataka (India); Kanive Parashiva, Guruprasad; Kapaettu, Satyamoorthy [Division of Biotechnology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Bola Sadashiva, Satish Rao, E-mail: satishraomlsc@gmail.com [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India)

2012-12-01

Purpose: Interindividual variability in normal tissue toxicity during radiation therapy is a limiting factor for successful treatment. Predicting the risk of developing acute reactions before initiation of radiation therapy may have the benefit of opting for altered radiation therapy regimens to achieve minimal adverse effects with improved tumor cure. Methods and Materials: DNA double-strand break (DSB) induction and its repair kinetics in lymphocytes of head-and-neck cancer patients undergoing chemoradiation therapy was analyzed by counting {gamma}-H2AX foci, neutral comet assay, and a modified version of neutral filter elution assay. Acute normal tissue reactions were assessed by Radiation Therapy Oncology Group criteria. Results: The correlation between residual DSBs and the severity of acute reactions demonstrated that residual {gamma}-H2AX foci in head-and-neck cancer patients increased with the severity of oral mucositis and skin reaction. Conclusions: Our results suggest that {gamma}-H2AX analysis may have predictive implications for identifying the overreactors to mucositis and skin reactions among head-and-neck cancer patients prior to initiation of radiation therapy.

Therapeutic effect of bee pollens on acute radiation sickness

International Nuclear Information System (INIS)

Wang Mingsuo; Huang Chaoqun; Chen Zhen; Huang Meiying; Jiang Ying; Wang Tao

1997-09-01

The therapeutic effect of bee pollens on acute radiation sickness were evaluated by observing the changes in the peripheral white blood cell (PWBC) count, the total activity of superoxide dismutase (SOD) and the levels of lipid peroxides (LPO) in sera of the irradiated rats following P.O. administration of bee pollens. It was found that bee pollens could remarkably help irradiated rats recover from radiation-induced injury. The functions of bee pollens might be summarized as follows: (1) Stimulating Proliferation of PWBC. The PWBC count of the bee pollens group showed no significant difference as compared with the normal control group on the 30 th day postirradiation. (2) Enhancing antioxidative effect of clearing free radicals. The total activity of serum SOD in the bee pollens group increased by 6.48% as compared with the normal control group on the 30 th day after irradiation, and the LPO levels i.e. MDA and POV in sera of the irradiated rats decreased by 54.73% and 21.60% respectively. The result suggests that using bee pollens as antiradiation and health-promoting agents in clinical treatment of acute radiation sickness and during radiotherapy of patients with tumors may has certain practical value. (12 refs., 2 figs., 2 tabs.)

Genetic risks from radiation

International Nuclear Information System (INIS)

Selby, P.B.

Two widely-recognized committees, UNSCEAR and BEIR, have reevaluated their estimates of genetic risks from radiation. Their estimates for gene mutations are based on two different approaches, one being the doubling-dose approach and the other being a new direct approach based on an empirical determination of the amount of dominant induced damage in the skeletons of mice in the first generation following irradiation. The estimates made by these committees are in reasonably good agreement and suggest that the genetic risks from present exposures resultng from nuclear power production are small. There is room for much improvement in the reliability of the risk estimates. The relatively new approach of measuring the amount of induced damage to the mouse skeleton shows great promise of improving knowledge about how changes in the mutation frequency affect the incidence of genetic disorders. Such findings may have considerable influence on genetic risk estimates for radiation and on the development of risk estimates for other less-well-understood environmental mutagens. (author)

Quantifying Cancer Risk from Radiation.

Science.gov (United States)

Keil, Alexander P; Richardson, David B

2017-12-06

Complex statistical models fitted to data from studies of atomic bomb survivors are used to estimate the human health effects of ionizing radiation exposures. We describe and illustrate an approach to estimate population risks from ionizing radiation exposure that relaxes many assumptions about radiation-related mortality. The approach draws on developments in methods for causal inference. The results offer a different way to quantify radiation's effects and show that conventional estimates of the population burden of excess cancer at high radiation doses are driven strongly by projecting outside the range of current data. Summary results obtained using the proposed approach are similar in magnitude to those obtained using conventional methods, although estimates of radiation-related excess cancers differ for many age, sex, and dose groups. At low doses relevant to typical exposures, the strength of evidence in data is surprisingly weak. Statements regarding human health effects at low doses rely strongly on the use of modeling assumptions. © 2017 Society for Risk Analysis.

Acute neurocognitive impairment during cranial radiation therapy in patients with intracranial tumors

International Nuclear Information System (INIS)

Welzel, Grit; Mai, Sabine K.; Hermann, Brigitte; Kraus-Tiefenbacher, Uta; Wenz, Frederik; Fleckenstein, Katharina; Duke University Medical Center Durham, NC

2008-01-01

The objective of the current study was to evaluate the acute effects of cranial radiation therapy (CNS-RT) using different radiation doses (0, 1.8, 2, 3, ≤ 20 Gy) on cognitive function with special emphasis on memory. We assessed patients with and without intracranial tumors to distinguish between direct and indirect radiation effects on brain tissue. Eighty-two patients were evaluated with neuropsychological testing before and acutely after radiotherapy (RT). Sixty-four patients received RT to the brain (55 with, 9 without intracranial tumor). Eighteen patients treated with RT to the breast served as controls. Patients with intracranial tumor demonstrated attention (19-38th percentile) and verbal memory scores (34-46th percentile) below the population average at baseline. The average Verbal Memory score was significantly different between patients with intracranial tumor and controls both at baseline (38th vs. 58th percentile) and after irradiation (27th vs. 52th percentile). Patients with preexisting peritumoral edema performed worse than patients without edema and controls. Radiation dose-related deficits were seen for working memory performance in patients with intracranial tumor. Our data indicate no measurable impairment of cognitive functioning acutely after prophylactic cranial irradiation. Patients with intracranial tumor show a deterioration of almost all memory functions with a dose-dependent impairment in working memory. Patients with preexisting peritumoral brain edema show the strongest deterioration. (orig.)

Acute neurocognitive impairment during cranial radiation therapy in patients with intracranial tumors

Energy Technology Data Exchange (ETDEWEB)

Welzel, Grit; Mai, Sabine K.; Hermann, Brigitte; Kraus-Tiefenbacher, Uta; Wenz, Frederik [University Medical Center Mannheim, Heidelberg Univ. (Germany). Dept. of Radiation Oncology; Fleckenstein, Katharina [University Medical Center Mannheim, Heidelberg Univ. (Germany). Dept. of Radiation Oncology]|[Duke University Medical Center Durham, NC (United States). Dept. of Radiation Oncology

2008-12-15

The objective of the current study was to evaluate the acute effects of cranial radiation therapy (CNS-RT) using different radiation doses (0, 1.8, 2, 3, {<=} 20 Gy) on cognitive function with special emphasis on memory. We assessed patients with and without intracranial tumors to distinguish between direct and indirect radiation effects on brain tissue. Eighty-two patients were evaluated with neuropsychological testing before and acutely after radiotherapy (RT). Sixty-four patients received RT to the brain (55 with, 9 without intracranial tumor). Eighteen patients treated with RT to the breast served as controls. Patients with intracranial tumor demonstrated attention (19-38th percentile) and verbal memory scores (34-46th percentile) below the population average at baseline. The average Verbal Memory score was significantly different between patients with intracranial tumor and controls both at baseline (38th vs. 58th percentile) and after irradiation (27th vs. 52th percentile). Patients with preexisting peritumoral edema performed worse than patients without edema and controls. Radiation dose-related deficits were seen for working memory performance in patients with intracranial tumor. Our data indicate no measurable impairment of cognitive functioning acutely after prophylactic cranial irradiation. Patients with intracranial tumor show a deterioration of almost all memory functions with a dose-dependent impairment in working memory. Patients with preexisting peritumoral brain edema show the strongest deterioration. (orig.)

Relations between radiation risks and radiation protection measuring techniques

International Nuclear Information System (INIS)

Herrmann, K.; Kraus, W.

1975-10-01

'Risk of damage' and 'exposure risk' are considered as components of the radiation risk. The influence of the 'exposure risk' on type and extent of radiation protection measurements is discussed with regard to different measuring tasks. Basing upon measuring results concerning the frequency of certain external and internal occupational exposures in the GDR, it has been shown that only a small fraction of the monitored persons are subjected to a high 'exposure risk'. As a consequence the following recommendations are given for discussion: (a) occupationally exposed persons with small 'exposure risk' should be monitored using only a long-term dosimeter (for instance a thermoluminescence dosimeter), (b) in the case of internal exposure the surface and, if necessary, air contamination should be controlled so strictly that routine measurements of internal contamination need not be performed. (author)

A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects

Energy Technology Data Exchange (ETDEWEB)

Blakely, Eleanor A.; Chang, Polly Y.

2007-02-26

The future of manned space flight depends on an analysis of the numerous potential risks of travel into deep space. Currently no radiation dose limits have been established for these exploratory missions. To set these standards more information is needed about potential acute and late effects on human physiology from appropriate radiation exposure scenarios, including pertinent radiation types and dose rates. Cancer risks have long been considered the most serious late effect from chronic daily relatively low-dose exposures to the complex space radiation environment. However, other late effects from space radiation exposure scenarios are under study in ground-based accelerator facilities and have revealed some unique particle radiation effects not observed with conventional radiations. A comprehensive review of pertinent literature that considers tissue effects of radiation leading to functional detriments in specific organ systems has recently been published (NCRP National Council on Radiation Protection and Measurements, Information Needed to Make Radiation Protection Recommendations for Space Missions Beyond Low-Earth Orbit, Report 153, Bethesda, MD, 2006). This paper highlights the review of two non-cancer concerns from this report: cardiovascular and immunological effects.

[Effects of radiation exposure on human body].

Science.gov (United States)

Kamiya, Kenji; Sasatani, Megumi

2012-03-01

There are two types of radiation health effect; acute disorder and late on-set disorder. Acute disorder is a deterministic effect that the symptoms appear by exposure above a threshold. Tissues and cells that compose the human body have different radiation sensitivity respectively, and the symptoms appear in order, from highly radiosensitive tissues. The clinical symptoms of acute disorder begin with a decrease in lymphocytes, and then the symptoms appear such as alopecia, skin erythema, hematopoietic damage, gastrointestinal damage, central nervous system damage with increasing radiation dose. Regarding the late on-set disorder, a predominant health effect is the cancer among the symptoms of such as cancer, non-cancer disease and genetic effect. Cancer and genetic effect are recognized as stochastic effects without the threshold. When radiation dose is equal to or more than 100 mSv, it is observed that the cancer risk by radiation exposure increases linearly with an increase in dose. On the other hand, the risk of developing cancer through low-dose radiation exposure, less 100 mSv, has not yet been clarified scientifically. Although uncertainty still remains regarding low level risk estimation, ICRP propound LNT model and conduct radiation protection in accordance with LNT model in the low-dose and low-dose rate radiation from a position of radiation protection. Meanwhile, the mechanism of radiation damage has been gradually clarified. The initial event of radiation-induced diseases is thought to be the damage to genome such as radiation-induced DNA double-strand breaks. Recently, it is clarified that our cells could recognize genome damage and induce the diverse cell response to maintain genome integrity. This phenomenon is called DNA damage response which induces the cell cycle arrest, DNA repair, apoptosis, cell senescence and so on. These responses act in the direction to maintain genome integrity against genome damage, however, the death of large number of

Tissue Respiration and Glycolysis in the Development of Acute Radiation Sickness

National Research Council Canada - National Science Library

Golubentsev, D

1960-01-01

The condition of tissue respiration and glycolysis in the development of acute radiation sickness has been insufficiently studied, and the factual data and opinions of various investigators are frequently contradictory...

Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation

Energy Technology Data Exchange (ETDEWEB)

Daila S. Gridley, PhD

2012-03-30

FINAL TECHNICAL REPORT Supported by the Low Dose Radiation Research Program, Office of Science U.S. Department of Energy Grant No. DE-FG02-07ER64345 Project ID: 0012965 Award Register#: ER64345 Project Manager: Noelle F. Metting, Sc.D. Phone: 301-903-8309 Division SC-23.2 noelle.metting@science.doe.gov Submitted March 2012 To: https://www.osti.gov/elink/241.3.jsp Title: Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation PI: Daila S. Gridley, Ph.D. Human low dose radiation data have been derived primarily from studies of space and airline flight personnel, nuclear plant workers and others exposed occupationally, as well as victims in the vicinity of atomic bomb explosions. The findings remain inconclusive due to population inconsistencies and complex interactions among total dose, dose rate, radiation quality and age at exposure. Thus, safe limits for low dose occupational irradiation are currently based on data obtained with doses far exceeding the levels expected for the general population and health risks have been largely extrapolated using the linear-nonthreshold dose-response model. The overall working hypothesis of the present study is that priming with low dose, low-linear energy transfer (LET) radiation can ameliorate the response to acute high-dose radiation exposure. We also propose that the efficacy of low-dose induced protection will be dependent upon the form and regimen of the high-dose exposure: photons versus protons versus simulated solar particle event protons (sSPE). The emphasis has been on gene expression and function of CD4+ T helper (Th) lymphocytes harvested from spleens of whole-body irradiated C57BL/6 mice, a strain that provides the genetic background for many genetically engineered strains. Evaluations of the responses of other selected cells, tissues such as skin, and organs such as lung, liver and brain were also initiated (partially funded by other sources). The long-term goal is to provide information

Anti-infection treatment of iatrogenic acute radiation sickness

International Nuclear Information System (INIS)

Zhang Shulan; Ke Xiaoyan; Jia Tengzhen

2006-01-01

Objective: To occumulatle experience of anti-infection treatment in acute radiation sickness (ARS) induced by medical treatment in order to provide beneficial help for victims of accidental of acute radiation sickness. Methods: The changes of peripheral blood indices, body temperature and clinical symptoms of 17 cases who were clinically irradiated with 6.0-7.2 Gy X-rays were observed both before peripheral blood stem cell transplantation(PBSCT) and after anti-infection treatment. Results: WBC count began to decrease to below 1 x 10 9 /L from the 8th to 10th days after irradiation and maintained at row level for 4 days or for 13.3 days if the patients had not received rhG-CSF treatment. In 29.4% of patients the body temperature was higher than 38.5 degree C. After comprehensive enviromental protection and anti-infection treatment, all patients could successfully tide over the period of bone marrow depression without appearance of the typical critical phase of ARS. Conclusion: PBSCT and rhG-CSF treatment can reduce the time span for reconstruction of bone marrow. Comprehensive enviromental protection and combined anti-infection treatment are key points fm successful treatment. (authors)

Acute stress affects risk taking but not ambiguity aversion.

Science.gov (United States)

Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

2014-01-01

Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

Lifetime radiation risks from low-dose rate radionuclides in beagles

International Nuclear Information System (INIS)

Goldman, M.; Rosenblatt, L.S.

1985-01-01

One of the largest, long-term (25-yr) animal studies on the effects of low-dose internal irradiation is almost completed. Some 335 beagles were given continuous exposure to graded 90 Sr [low linear energy transfer (LET)] in their diets (D-dogs) through adulthood. A second group (R-dogs) was given fractionated doses of 225 Ra (high LET) as young adults. A third group of 44 was given a single injection of 90 Sr as adults (S-dogs) to compare single to continuous dosages. All dogs were followed through their lifetimes. Only one of the 848 dogs is still alive. The animals were whole-body counted over their entire life span and were examined frequently for assessment of medical status. There were no acute radiation lethalities. Analyses of the large data base from these dogs have begun and preliminary indications are that 90 Sr, which was tested over a 1500-fold skeletal dose rate range, does not cause significant life shortening at average accumulation skeletal doses of ∼2500 rads (25 Gy) and that a curvilinear dose response curve for life shortening was seen at higher accumulation doses. The data will be discussed in terms of modern epidemiological concepts and quantifications will be related to certain parameters of human risk from acute or chronic radiation exposures

Evidence Report: Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure

Science.gov (United States)

Patel, Zarana; Huff, Janice; Saha, Janapriya; Wang, Minli; Blattnig, Steve; Wu, Honglu; Cucinotta, Francis

2015-01-01

Occupational radiation exposure from the space environment may result in non-cancer or non-CNS degenerative tissue diseases, such as cardiovascular disease, cataracts, and respiratory or digestive diseases. However, the magnitude of influence and mechanisms of action of radiation leading to these diseases are not well characterized. Radiation and synergistic effects of radiation cause DNA damage, persistent oxidative stress, chronic inflammation, and accelerated tissue aging and degeneration, which may lead to acute or chronic disease of susceptible organ tissues. In particular, cardiovascular pathologies such as atherosclerosis are of major concern following gamma-ray exposure. This provides evidence for possible degenerative tissue effects following exposures to ionizing radiation in the form of the GCR or SPEs expected during long-duration spaceflight. However, the existence of low dose thresholds and dose-rate and radiation quality effects, as well as mechanisms and major risk pathways, are not well-characterized. Degenerative disease risks are difficult to assess because multiple factors, including radiation, are believed to play a role in the etiology of the diseases. As additional evidence is pointing to lower, space-relevant thresholds for these degenerative effects, particularly for cardiovascular disease, additional research with cell and animal studies is required to quantify the magnitude of this risk, understand mechanisms, and determine if additional protection strategies are required.The NASA PEL (Permissive Exposure Limit)s for cataract and cardiovascular risks are based on existing human epidemiology data. Although animal and clinical astronaut data show a significant increase in cataracts following exposure and a reassessment of atomic bomb (A-bomb) data suggests an increase in cardiovascular disease from radiation exposure, additional research is required to fully understand and quantify these adverse outcomes at lower doses (less than 0.5 gray

Training loads and injury risk in Australian football-differing acute: chronic workload ratios influence match injury risk.

Science.gov (United States)

Carey, David L; Blanch, Peter; Ong, Kok-Leong; Crossley, Kay M; Crow, Justin; Morris, Meg E

2017-08-01

(1) To investigate whether a daily acute:chronic workload ratio informs injury risk in Australian football players; (2) to identify which combination of workload variable, acute and chronic time window best explains injury likelihood. Workload and injury data were collected from 53 athletes over 2 seasons in a professional Australian football club. Acute:chronic workload ratios were calculated daily for each athlete, and modelled against non-contact injury likelihood using a quadratic relationship. 6 workload variables, 8 acute time windows (2-9 days) and 7 chronic time windows (14-35 days) were considered (336 combinations). Each parameter combination was compared for injury likelihood fit (using R 2 ). The ratio of moderate speed running workload (18-24 km/h) in the previous 3 days (acute time window) compared with the previous 21 days (chronic time window) best explained the injury likelihood in matches (R 2 =0.79) and in the immediate 2 or 5 days following matches (R 2 =0.76-0.82). The 3:21 acute:chronic workload ratio discriminated between high-risk and low-risk athletes (relative risk=1.98-2.43). Using the previous 6 days to calculate the acute workload time window yielded similar results. The choice of acute time window significantly influenced model performance and appeared to reflect the competition and training schedule. Daily workload ratios can inform injury risk in Australian football. Clinicians and conditioning coaches should consider the sport-specific schedule of competition and training when choosing acute and chronic time windows. For Australian football, the ratio of moderate speed running in a 3-day or 6-day acute time window and a 21-day chronic time window best explained injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Characterising risk - aggregated metrics: radiation and noise

International Nuclear Information System (INIS)

Passchier, W.

1998-01-01

The characterisation of risk is an important phase in the risk assessment - risk management process. From the multitude of risk attributes a few have to be selected to obtain a risk characteristic or profile that is useful for risk management decisions and implementation of protective measures. One way to reduce the number of attributes is aggregation. In the field of radiation protection such an aggregated metric is firmly established: effective dose. For protection against environmental noise the Health Council of the Netherlands recently proposed a set of aggregated metrics for noise annoyance and sleep disturbance. The presentation will discuss similarities and differences between these two metrics and practical limitations. The effective dose has proven its usefulness in designing radiation protection measures, which are related to the level of risk associated with the radiation practice in question, given that implicit judgements on radiation induced health effects are accepted. However, as the metric does not take into account the nature of radiation practice, it is less useful in policy discussions on the benefits and harm of radiation practices. With respect to the noise exposure metric, only one effect is targeted (annoyance), and the differences between sources are explicitly taken into account. This should make the metric useful in policy discussions with respect to physical planning and siting problems. The metric proposed has only significance on a population level, and can not be used as a predictor for individual risk. (author)

Acute Radiation Syndrome. Consequences and outcomes

International Nuclear Information System (INIS)

Okladnikova, N.D.; Pesternikova, V.S.; Sumina, M.V.; Azizova, T.V.; Yurkov, N.N.

2000-01-01

The consequences and outcomes of an Acute Radiation Syndrome (ARS), induced by external gamma radiation for 59 persons (49 men and 10 women) have been estimated. All incidents have taken place more than 40 years ago in the yearly years of adjustment of an atomic industry (1950-1953-38 persons, 1954-1958-21 persons). According to the degree of severity ARS 5 groups are selected: the severest degree - 7 individuals (average dose in group 43.8±12.8 Sv), severe - 4 individuals (9.3±1.5 Sv), medium - 14 individuals (2.2±0.8 Sv), a light degree - 15 individuals (0.93±0.13 Sv), ''erased'' from - 19 individuals (0.85±0.07 Sv). In all cases, except for lethal (the severest degree), the characteristics of morphological composition of the peripheral blood were restored in the first year after ARS and now correspond to physiological standard. In 2 cases the moderate hypoplasia of granulocytopoiesis was diagnosed. A marker of the acute exposure was the chromosome aberrations in lymphocytes of the peripheral blood. The frequency of chromosome aberrations correlates with severity degree of ARS (from 3-7 up to 35-50 stable aberrations per 100 cells). In cases of ARS with severe degree the early development of a cerebral atherosclerosis is detected. The radiation cataract was diagnosed in 5 patients (an exposure doses 4.0-9.8 Sv, a period of development 2-5 years). During the first years after ARS in 80% of cases the complete labour rehabilitation is reached. Of 53 patients with known vital status by 45 year of monitoring 19 persons (35.8%) have died, of these in 2 cases the causes of death are not determined. In remaining cases the causes of death were ARS of severest degree (7 persons), Ischemic Heart Disease (5 persons), malignant tumors (4 persons), accidents and traumas (2 persons). (author)

Radiation risk from CT: implications for cancer screening.

Science.gov (United States)

Albert, Jeffrey M

2013-07-01

The cancer risks associated with patient exposure to radiation from medical imaging have become a major topic of debate. The higher doses necessary for technologies such as CT and the increasing utilization of these technologies further increase medical radiation exposure to the population. Furthermore, the use of CT for population-based cancer screening continues to be explored for common malignancies such as lung cancer and colorectal cancer. Given the known carcinogenic effects of ionizing radiation, this warrants evaluation of the balance between the benefit of early cancer detection and the risk of screening-induced malignancy. This report provides a brief review of the process of radiation carcino-genesis and the literature evaluating the risk of malignancy from CT, with a focus on the risks and benefits of CT for cancer screening. The available data suggest a small but real risk of radiation-induced malignancy from CT that could become significant at the population level with widespread use of CT-based screening. However, a growing body of literature suggests that the benefits of CT screening for lung cancer in high-risk patients and CT colonography for colorectal cancer may significantly outweigh the radiation risk. Future studies evaluating the benefits of CT screening should continue to consider potential radiation risks.

Health risk assessment of exposure to ionizing radiation

International Nuclear Information System (INIS)

Ogata, Hiromitsu

2011-01-01

Risk assessment is an essential process for evaluating the human health effects of exposure to ionizing radiation and for determining acceptable levels of exposure. There are two major components of radiation risk assessment: a measure of exposure level and a measure of disease occurrence. For quantitative estimation of health risks, it is important to evaluate the association between exposure and disease occurrence using epidemiological or experimental data. In these approaches, statistical risk models are used particularly for estimating cancer risks related to exposure to low levels of radiation. This paper presents a summary of basic models and methods of risk assessment for studying exposure-risk relationships. Moreover, quantitative risk estimates are subject to several sources of uncertainty due to inherent limitations in risk assessment studies. This paper also discusses the limitations of radiation risk assessment. (author)

Acceptable level of radiation risk and its perception

International Nuclear Information System (INIS)

Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

1987-01-01

The acceptable level of radiation risk for public members, that is 10 -5 /y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10 -5 /y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10 -5 /y as acceptable risk level in Japan. The perception to risk level of 10 -5 /y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one. (author)

Biological effects of radiation and estimation of risk to radiation workers

International Nuclear Information System (INIS)

Murthy, M.S.S.

1987-01-01

The biological effects of radiation have three stages: physical, chemical and biological. A precise mathematical description of biological effects and of one-to-one correspondence between the initial energy absorption and final effect has not been possible, because several factors are involved in biological effects and their manifestation period varies from less than one second to several years. The mechanism of biological radiation effects is outlined. The two groups of these effects are (1) immediate and (2) delayed. The main aim of radiation protection programme is to eliminate the risk of non-stochastic effects to an acceptable level. The mean annual dose for 30,000 radiation workers in India is 2.7 m Sv. Estimated risk of fatal cancer from this dose is about 50 cases of cancer per year per million workers which is well below the ICRP standard for safe occupation stipulated at fatality rate less than or equal to 100 per year per milion workers. When compared with risk in other occupations, the risk to radiation workers is much less. (M.G.B.)

Sucralfate does not ameliorate acute radiation proctitis: randomised study and meta-analysis.

Science.gov (United States)

Hovdenak, N; Sørbye, H; Dahl, O

2005-09-01

During pelvic radiotherapy, many patients develop radiation-induced gastrointestinal symptoms, which may interfere with treatment. Prophylaxis during radiotherapy should ideally prevent acute reaction and the development of delayed injury. Sucralfate, an aluminium sucrose octasulphate, has been used for acute and delayed radiation side-effects. However, conflicting results have been published. We report here a prospective, randomised, placebo-controlled study of prophylactic sucralfate during pelvic radiotherapy. In addition, a meta-analysis of available data from the literature has been carried out. Fifty-one patients with localised pelvic tumours scheduled for curative conformal pelvic radiotherapy (total dose 64-70 Gy over 6.5-7 weeks in 2 Gy daily fractions) were included. Peroral sucralfate 2 g three times daily, or identically appearing placebo tablets, was given during the course of radiotherapy. Symptom registration, endoscopy and biopsies were carried out immediately before radiotherapy, 2 weeks and 6 weeks into the treatment course, and 2 weeks after completing radiotherapy. Mucosal cup forceps biopsies were obtained through a rigid proctoscope. Graded endoscopic appearance and quantitative histology were registered. On the basis of previously published negative reports, an unplanned interim analysis of 44 evaluable patients showed significantly increased diarrhoea in the sucralfate group and the trial was stopped. No difference was seen in other symptoms, endoscopic appearance or histology. A meta-analysis comprising five published studies showed no statistically significant beneficial effect of sucralfate on acute symptoms. Sucralfate cannot be recommended for prophylaxis of acute radiation proctopathy and may even worsen the symptoms.

Epidemiological data and radiation risk estimates

International Nuclear Information System (INIS)

Cardis, E.

2002-01-01

The results of several major epidemiology studies on populations with particular exposure to ionizing radiation should become available during the first years of the 21. century. These studies are expected to provide answers to a number of questions concerning public health and radiation protection. Most of the populations concerned were accidentally exposed to radiation in ex-USSR or elsewhere or in a nuclear industrial context. The results will complete and test information on risk coming from studies among survivors of the Hiroshima and Nagasaki atomic bombs, particularly studies on the effects of low dose exposure and prolonged low-dose exposure, of different types of radiation, and environmental and host-related factors which could modify the risk of radiation-induced effects. These studies are thus important to assess the currently accepted scientific evidence on radiation protection for workers and the general population. In addition, supplementary information on radiation protection could be provided by formal comparisons and analyses combining data from populations with different types of exposure. Finally, in order to provide pertinent information for public health and radiation protection, future epidemiology studies should be targeted and designed to answer specific questions, concerning, for example, the risk for specific populations (children, patients, people with genetic predisposition). An integrated approach, combining epidemiology and studies on the mechanisms of radiation induction should provide particularly pertinent information. (author)

Radiation risk due to occupational exposure

International Nuclear Information System (INIS)

Kargbo, A.A

2012-04-01

Exposure to ionizing radiation occurs in many occupations. Workers can be exposed to both natural and artificial sources of radiation. Any exposure to ionizing radiation incurs some risk, either to the individual or to the individual's progeny. This dissertation investigated the radiation risk due to occupational exposure in industrial radiography. Analysis of the reported risk estimates to occupational exposure contained in the UNSCEAR report of 2008 in industrial radiography practice was done. The causes of accidents in industrial radiography include: Lack of or inadequate regulatory control, inadequate training, failure to follow operational procedures, human error, equipment malfunction or defect, inadequate maintenance and wilful violation have been identified as primary causes of accidents. To minimise radiation risks in industrial radiography exposure devices and facilities should be designed such that there is intrinsic safety and operational safety ensured by establishing a quality assurance programme, safety culture fostered and maintained among all workers, industrial radiography is performed in compliance with approved local rules, workers engaged have appropriate qualifications and training, available safe operational procedures are followed, a means is provided for detecting incidents and accidents and an analysis of the causes and lessons learned. (author)

The Impact of Pretreatment Prostate Volume on Severe Acute Genitourinary Toxicity in Prostate Cancer Patients Treated With Intensity-Modulated Radiation Therapy

International Nuclear Information System (INIS)

Aizer, Ayal A.; Anderson, Nicole S.; Oh, Steven C.; Yu, James B.; McKeon, Anne M.; Decker, Roy H.; Peschel, Richard E.

2011-01-01

Purpose: To assess the impact of pretreatment prostate volume on the development of severe acute genitourinary toxicity in patients undergoing intensity-modulated radiation therapy (IMRT) for prostate cancer. Methods and Materials: Between 2004 and 2007, a consecutive sample of 214 patients who underwent IMRT (75.6 Gy) for prostate cancer at two referral centers was analyzed. Prostate volumes were obtained from computed tomography scans taken during treatment simulation. Genitourinary toxicity was defined using the National Cancer Institute Common Terminology Criteria for Adverse Events Version 3.0 guidelines. Acute toxicity was defined as any toxicity originating within 90 days of the completion of radiation therapy. Patients were characterized as having a small or large prostate depending on whether their prostate volume was less than or greater than 50 cm 3 , respectively. Genitourinary toxicity was compared in these groups using the chi-square or Fisher's exact test, as appropriate. Bivariate and multivariate logistic regression analysis was performed to further assess the impact of prostate volume on severe (Grade 3) acute genitourinary toxicity. Results: Patients with large prostates (>50 cm 3 ) had a higher rate of acute Grade 3 genitourinary toxicity (p = .02). Prostate volume was predictive of the likelihood of developing acute Grade 3 genitourinary toxicity on bivariate (p = .004) and multivariate (p = .006) logistic regression. Every 27.0 cm 3 increase in prostate volume doubled the likelihood of acute Grade 3 genitourinary toxicity. Conclusions: Patients with larger prostates are at higher risk for the development of severe acute genitourinary toxicity when treated with IMRT for prostate cancer.

Chronic and Acute Relational Risk Factors for Dating Aggression in Adolescence and Young Adulthood.

Science.gov (United States)

Collibee, Charlene; Furman, Wyndol

2016-04-01

Dating aggression is a prevalent and costly public health concern. Using a relational risk framework, this study examined acute and chronic relational risk factors (negative interactions, jealousy, support, and relationship satisfaction) and their effects on physical and psychological dating aggression. The study also examined the interaction between chronic and acute risk, allowing us to assess how changes in acute risk have differing effects depending on whether the individual is typically at higher chronic risk. A sample of 200 youth (100 female) completed seven waves of data, which spanned 9 years from middle adolescence to young adulthood (M age at Wave 1 = 15.83). Using hierarchical linear modeling, analyses revealed both acute (within-person) and chronic (between-person) levels in jealousy, negative interactions, and relationship satisfaction, were associated with physical and psychological dating aggression. Significant interactions between chronic and acute risk emerged in predicting physical aggression for negative interactions, jealousy, and relationship satisfaction such that those with higher levels of chronic risk are more vulnerable to increases in acute risk. These interactions between chronic and acute risk indicate that risk is not static, and dating aggression is particularly likely to occur at certain times for youth at high risk for dating aggression. Such periods of increased risk may provide opportunities for interventions to be particularly effective in preventing dating aggression or its consequences. Taken together, these findings provide support for the role of relational risk factors for dating aggression. They also underscore the importance of considering risk dynamically.

Development of a murine model of acute radiation encephalopathy

International Nuclear Information System (INIS)

Xing Yigang; Tang Yamei; Liu Jun; Sun Ying

2003-01-01

Objective: To develop a murine model of acute radiation encephalopathy. Methods: A total of 40 rats were subjected to local γ-irradiation to the brain with the dosage of 7 Gy/d for 6 consecutive days. The amount of food intake, hairs and skin of irradiated field, body weight, general activities, CNS symptoms and signs were examined and recorded after irradiation. On day 3, 7, 14 and 30, the brain tissue was removed to observe histopathologic changes. Results: During the first two days after irradiation, the irradiated rats were agitated, and the amount of food intake decreased from day 2 onwards. No serious skin reaction to irradiation was observed. Survived rats had normal activities without any abnormal nervous signs. Histopathologic changes showed slight neuronal degeneration, smaller cell body, red-colored cytoplasm, disappearance of Nissl body, vacuolation, typical cell shrinkage, chromatin condensation and nuclear divergence. On the 14th and 30th days, hypochromatism, loose and reticular necrotic foci were found in some samples. Conclusion: The murine model of acute radiation encephalopathy is useful and practical in radiobiological studies

Perception of radiation risks

International Nuclear Information System (INIS)

Brenot, J.

1992-01-01

Perception of risks by people depends on many factors, either characterizing the individuals, or specific to the risk sources. The risk concept, which confuses the issue, is precised first. Second, the perception phenomenon is presented as an interactive process involving the individual, the hazard, and the social context. Third, dimensions of perception are listed and used to describe the perception of radiation risks. Finally, the relation between perception and attitude is clarified. (author) 50 refs

Association of oesophageal radiation dose volume metrics, neutropenia and acute radiation oesophagitis in patients receiving chemoradiotherapy for non-small cell lung cancer

International Nuclear Information System (INIS)

Everitt, Sarah; Duffy, Mary; Bressel, Mathias; McInnes, Belinda; Russell, Christine; Sevitt, Tim; Ball, David

2016-01-01

The relationship between oesophageal radiation dose volume metrics and dysphagia in patients having chemoradiation (CRT) for non-small cell lung cancer (NSCLC) is well established. There is also some evidence that neutropenia is a factor contributing to the severity of oesophagitis. We retrospectively analysed acute radiation oesophagitis (ARO) rates and severity in patients with NSCLC who received concurrent chemotherapy and high dose radiation therapy (CRT). We investigated if there was an association between grade of ARO, neutropenia and radiation dose volume metrics. Patients with NSCLC having concurrent CRT who had RT dose and toxicity data available were eligible. Exclusion criteria included previous thoracic RT, treatment interruptions and non-standard dose regimens. RT dosimetrics included maximum and mean oesophageal dose, oesophagus dose volume and length data. Fifty four patients were eligible for analysis. 42 (78 %) patients received 60 Gy. Forty four (81 %) patients received carboplatin based chemotherapy. Forty eight (89 %) patients experienced ARO ≥ grade 1 (95 % CI: 78 % to 95 %). ARO grade was associated with mean dose (r s = 0.27, p = 0.049), V20 (r s = 0.31, p = 0.024) and whole oesophageal circumference receiving 20 Gy (r s = 0.32 p = 0.019). In patients who received these doses, V20 (n = 51, r s = 0.36, p = 0.011), V35 (n = 43, r s = 0.34, p = 0.027) and V60 (n = 25, r s = 0.59, P = 0.002) were associated with RO grade. Eleven of 25 (44 %) patients with ARO ≥ grade 2 also had ≥ grade 2 acute neutropenia compared with 5 of 29 (17 %) patients with RO grade 0 or 1 (p = 0.035). In addition to oesophageal dose-volume metrics, neutropenia may also be a risk factor for higher grades of ARO

Radiation risks for patients having X rays

International Nuclear Information System (INIS)

Hale, J.; Thomas, J.W.

1985-01-01

In addition to radiation from naturally occurring radioactive materials and cosmic rays, individuals in developed countries receive radiation doses to bone marrow and gonads from the medical diagnostic use of X rays. A brief discussion of radiation epidemiology shows that deleterious effects are low even when doses are high. The concept of acceptable risk is introduced to help evaluate the small, but still existent, risks of radiation dose. Examples of bone marrow and gonadal doses for representative X-ray examinations are presented along with the current best estimates, per unit of X-ray dose, of the induction of leukemia or of genetic harm. The risk to the patient from an examination can then be compared with the normal risk of mortality from leukemia or of the occurrence of genetic defects. The risk increase is found to be very low. The risks to unborn children from radiographic examinations are also discussed. The benefit to the patient from information obtained from the examination must be balanced against the small risks

Acceptable level of radiation risk and its perception

Energy Technology Data Exchange (ETDEWEB)

Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

1987-03-01

The acceptable level of radiation risk for public members, that is 10/sup -5//y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10/sup -5//y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10/sup -5//y as acceptable risk level in Japan. The perception to risk level of 10/sup -5//y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one.

Radiation risks in perspective

International Nuclear Information System (INIS)

Pochin, E.E.

1987-01-01

The problem of risk assessment is greater at the low effective dose rates now observed in the majority of all forms of exposure, usually of less than 3 mSv per year from natural causes, from occupational exposure, and from exposure of 'critical groups' of the general public. For most populations there are particular problems also in epidemiological studies at low dose, in addition to those due to the very large numbers of person-years that need to be studied and the long latencies of most radiation effects. Adequate estimates can, however, now be made of the carcinogenic risk of exposure at higher dose of various organs selectively and of the whole body uniformly, and of modes of inference to the risk at lower dose. Estimates can also be made of the risks of inducing major types of inheritable and developmental abnormality. An essential step in viewing the sum of all such radiation risks in the perspective of other occupational and public risks must now be to develop an informed consensus on the relative weight that is regarded as attaching to hazards of different kind and severity. (author)

Hypofractionation does not increase radiation pneumonitis risk with modern conformal radiation delivery techniques

DEFF Research Database (Denmark)

Vogelius, Ivan R; Westerly, David C; Cannon, George M

2010-01-01

To study the interaction between radiation dose distribution and hypofractionated radiotherapy with respect to the risk of radiation pneumonitis (RP) estimated from normal tissue complication probability (NTCP) models.......To study the interaction between radiation dose distribution and hypofractionated radiotherapy with respect to the risk of radiation pneumonitis (RP) estimated from normal tissue complication probability (NTCP) models....

Postoperative radiation therapy after hip replacement in high-risk patients for development of heterotopic bone formation

International Nuclear Information System (INIS)

Hashem, R.; Rene, N.; Souhami, L.; Tanzer, M.; Evans, M.

2011-01-01

Purpose. - To report the results of postoperative radiation therapy in preventing the development of heterotopic bone formation after hip replacement surgery in high-risk patients. Patients and methods. - Between 1991 and 2007, 44 patients were preventively treated with postoperative RT after total hip replacement. In total, 47 hips were treated. All patients were considered at high risk for developing heterotopic bone formation. Most patients (63.5%) were treated because of a history of severe osteoarthritis or ankylosing spondylitis. All patients were treated with shaped parallel-opposed fields with a single fraction of 7 Gy using 6 or 18 MV photons. Most patients (94%) received radiation therapy within 72 hours postoperative and in only three patients radiation therapy was delivered after 72 hours post-surgery (5-8 days). Results. - Minimum follow-up was 1 year. There were 18 females and 26 males. Median age was 63 years (range: 18-80). Treatments were well tolerated and no acute toxicity was seen post-radiation therapy. Only one of the 47 hips (2%) developed heterotopic bone formation. This patient received postoperative radiation therapy to both hips but only developed heterotopic bone formation in one of them. None of the three patients treated beyond 72 hours failed. To date no late toxicity has been observed. Conclusion. - The use of postoperative radiation therapy was an effective and safe treatment in the prevention of heterotopic bone formation in a high-risk group of patients undergoing total hip replacement. (authors)

Dose Response for Monokaryon mycelium of Pleurotus pulmonarius After Acute Gamma Radiation

International Nuclear Information System (INIS)

Wan Safina Wan Abdul Razak; Azhar Mohamad; Nie, H.J.

2016-01-01

Pleurotus pulmonarius is locally known as Grey oyster. The species is popular and widely cultivated throughout the world mostly in Asia Europe as their simple and low cost production technology and higher biological efficiency. Mutation induction is an alternative ways for improving available commercial strain for better quality traits. Dose response is important in evaluating effects of mutagenesis via acute gamma radiation. Monokaryon mycelium of Pleurotus pulmonarius was exposed to acute gamma radiation ranged from 0 Gy, 0.1 kGy, 0.2 kGy, 0.3 kGy, 0.4 kGy, 0.5 kGy, 0.6 kGy, 0.7 kGy, 0.8 kGy, 0.9 kGy, 1.0 kGy, 1.5 Gy, 2.0 kGy, 3.0 kGy and 4.0 kGy at dose rate 0.013 kGy/ min. growth performance was measured at 2 days interval to get the LD_5_0. Increasing of the irradiation dose found to decrease the growth performance of the monokaryon mycelium. LD_5_0 was revealed at 1.56 kGy for mono karyon mycelium. Discoveries of the works are important for the improvement of Pleurotus species via acute gamma radiation and benefiting to growers and mushroom industries. (author)

Risk Factors of Nicardipine-Related Phlebitis in Acute Stroke Patients.

Science.gov (United States)

Kawada, Kei; Ohta, Tsuyoshi; Tanaka, Koudai; Kadoguchi, Naoto; Yamamoto, Souichi; Morimoto, Masanori

2016-10-01

Intravenous nicardipine is generally used to treat hypertension in acute stroke patients but is associated with frequent phlebitis. We aimed to identify the incidence and risk factors of phlebitis in such patients. The incidence and risk factors of phlebitis were investigated in 358 acute stroke patients from July 2014 to June 2015. In total, 138 patients received intravenous nicardipine. Of 45 (12.6%) phlebitis patients in 358 acute stroke patients, 42 (93.3%) were administered nicardipine, which was significantly associated with phlebitis occurrence (P phlebitis of acute stroke patients in univariate analysis were intracerebral hemorrhage (P phlebitis is frequently observed in acute stroke patients and is significantly associated with administration of a maximum concentration of nicardipine greater than 130 µg/mL. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Radiation risk perception in Institute 'Vinca'

International Nuclear Information System (INIS)

Milanovic, S.; Pavlovic, S

1999-01-01

The necessity for research and development of risk analysis methods arise from practical needs for safety for men and environment. Relating to speed of technological development risk is implemented in modern technological achievements. Complexity of approach to the concept of risk presents the essence of risk management. Risk management means to apply risk analysis in order to risk decrease and control. Database for risk management is in technical social, economic and political area. Risk perception is a construction in the field of social psychology i.e. public opinion research. These results are of importance for the risk management. Research presented in this paper has been done on the sample of 240 examines with two basic sub samples: person working with ionizing radiation (140 of them) and persons not working with ionizing radiation (100 of them). Attitudes to risk definition risk acceptance and relation to risk consequences. (author)

Post-ERCP acute pancreatitis and its risk factors.

Science.gov (United States)

Iorgulescu, A; Sandu, I; Turcu, F; Iordache, N

2013-03-15

Endoscopic retrograde cholangiopancreatography (ERCP) is a complex endoscopic technique that evolved from a diagnostic to a mainly therapeutic procedure. This was due to the identification of post-procedural complications that can follow both simple ERCP and that associated with the instrumentation of the biliary and pancreatic ductals. The identification of post ERCP complications in a proportion of 5 to 10% of cases, with a mortality rate of 0.33%, imposed their analysis and study of risk factors involved in their occurrence. The significance of post ERCP complications reveals the necessity of their avoidance by adopting additional measures if risk factors are identified. We have retrospectively analyzed 900 cases that underwent ERCP in the Surgery Department of "Sf. Ioan" Clinical Hospital in a period of 17 years. The complications of the procedure were studied. Among them, a special attention was given to post-ERCP acute pancreatitis (pERCP-AP), the most common complication that occurred in the study group. We also tried to find out and highlight the risk factors for this complication. ERCP is a relatively safe invasive procedure, yet it has complications (8% of cases), some of them potentially fatal (mortality 0.43%). The most common complications after ERCP are acute pancreatitis (3.7%), papillary bleeding (1.04%), retroperitoneal duodenal perforation (0.69%) and biliary septic complications like acute cholecystitis and cholangitis (1.21%). Acute pancreatitis is by far the most common complication. Risk factors for its occurrence are difficult sphincterotomy with precut use, failure of CBD desobstruction, pancreatic sphincterotomy, repeated injection of contrast in the pancreatic ductal system, dysfunction of the sphincter of Oddi and the absence of changes of chronic pancreatitis. When risk factors are identified, the patients' selection must be very strict and diagnostic ERCP should be avoided in favor of non-invasive diagnostic methods (MRI

Calculating Risk: Radiation and Chernobyl.

Science.gov (United States)

Gale, Robert Peter

1987-01-01

Considers who is at risk in a disaster such as Chernobyl. Assesses the difficulty in translating information regarding radiation to the public and in determining the acceptability of technological risks. (NKA)

Low-level radiation risks in people

International Nuclear Information System (INIS)

Goloman, M.; Filjushkin, V. lgor

1993-01-01

Using the limited human data plus the relationships derived from the laboratory, a leukemia risk model has been developed as well as a suggested model for other cancers in people exposed to low levels of radiation. Theoretical experimental and epidemiological evidence will be presented in an integrated stochastic model for projection of radiation-induced cancer risks

Role of radiation in the treatment of acute myelogenous leukaemia

Energy Technology Data Exchange (ETDEWEB)

Honeyman, L D; Morgan, D E [Groote Schuur Hospital, Cape Town (South Africa). Dept. of Radiotherapy

1982-06-01

The article deals with the radiation treatment of acute myelogenous leukaemia. The contribution of radiotherapy can be considered in three parts: a) irradiation of blood packs for patient support; b) irradiation of laboratory animals in order to improve existing knowledge and techniques; c) total body irradiation of the patient on the day of the transplant using a dose large enough to destroy the bone marrow and the immune system. The radiation effects, post graft immunosuppression and the supporting of the patient after transplantation are also discussed.

To manage the ionizing radiations risks

International Nuclear Information System (INIS)

Metivier, H.; Romerio, F.

2000-01-01

Mister Romerio's work tackles the problem of controversy revealed by the experts in the field of estimation and management of ionizing radiations risks. The author describes the three paradigms at the base of the debate: the relationship without threshold (typified by the ICRP and its adepts), these ones that think that low doses risks are overestimated ( Medicine Academia for example) or that ones that believe that dose limits are too severe and induce unwarranted costs; then that ones that think that these risks are under-estimated and limits should be more reduced, even stop these practices that lead to public exposure to ionizing radiations. The author details the uncertainties about the risk estimations, refreshes the knowledge in radiation protection with the explanations of the different paradigms. At the end a table summarize the positions of the three paradigms

Risk determination after an acute myocardial infarction: review of 3 clinical risk prediction tools.

Science.gov (United States)

Scruth, Elizabeth Ann; Page, Karen; Cheng, Eugene; Campbell, Michelle; Worrall-Carter, Linda

2012-01-01

The objective of the study was to provide comprehensive information for the clinical nurse specialist (CNS) on commonly used clinical prediction (risk assessment) tools used to estimate risk of a secondary cardiac or noncardiac event and mortality in patients undergoing primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). The evolution and widespread adoption of primary PCI represent major advances in the treatment of acute myocardial infarction, specifically STEMI. The American College of Cardiology and the American Heart Association have recommended early risk stratification for patients presenting with acute coronary syndromes using several clinical risk scores to identify patients' mortality and secondary event risk after PCI. Clinical nurse specialists are integral to any performance improvement strategy. Their knowledge and understandings of clinical prediction tools will be essential in carrying out important assessment, identifying and managing risk in patients who have sustained a STEMI, and enhancing discharge education including counseling on medications and lifestyle changes. Over the past 2 decades, risk scores have been developed from clinical trials to facilitate risk assessment. There are several risk scores that can be used to determine in-hospital and short-term survival. This article critiques the most common tools: the Thrombolytic in Myocardial Infarction risk score, the Global Registry of Acute Coronary Events risk score, and the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications risk score. The importance of incorporating risk screening assessment tools (that are important for clinical prediction models) to guide therapeutic management of patients cannot be underestimated. The ability to forecast secondary risk after a STEMI will assist in determining which patients would require the most aggressive level of treatment and monitoring postintervention including

EVALUATION OF RISK FACTORS IN ACUTE STROKE

Directory of Open Access Journals (Sweden)

Putta

2015-03-01

Full Text Available Introduction: Cerebrovascular disease is the third most common cause of death in the developed world after cancer and ischemic heart disease. In India, community surveys have shown a crude prevalence rate of 200 per 100000 population for hemiplegia. Aims and objectives: Identification of risk factors for c erebrovascular disease. Materials and Methods: Inclusion Criteria: Cases of acute stroke admitted in S.V.R.R.G.G.H, Tirupati were taken for the study. Exclusion Criteria: Head injury cases, neoplasm cases producing cerebrovascular disease were excluded. Re sults: Stroke was more common in male, 54% patients were male 46% were female. It was more common in 6 th and 7 th decade. More common risk factors were hypertension followed by smoking, diabetes mellitus. More common pathology was infarction. Conclusion: Com mon risk factors for acute stroke are hypertension, smoking, diabetes mellitus, alcoholism, obesity, cardiac disease. Stroke was confirmed by CT scan of brain.

The acute radiation syndrome in the 137Cs Brazilian accident, 1987

International Nuclear Information System (INIS)

Valverde, N.J.; Cordeiro, J.M.; Oliveira, A.R.; Brandao Mello, C.E.

1989-01-01

Eight patients with the most severe degreed of bone marrow impairment are studied. Case descriptions are limited to manifestations and complications related to the 'Acute Radiation Syndrome' (ARS). Medical facilities, exams and therapeutic management are discussed. (MAC) [pt

Clinical outcomes of image guided radiation therapy (IGRT) with gold fiducial vaginal cuff markers for high-risk endometrial cancer

Energy Technology Data Exchange (ETDEWEB)

Monroe, Alan T.; Peddada, Anuj V. [Dept. of Radiation Oncology, Penrose Cancer Center, Colorado Springs (United States); Pikaart, Dirk [Dept. of Gynecologic Oncology, Penrose Cancer Center, Colorado Springs (United States)

2013-06-15

Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered.

Clinical outcomes of image guided radiation therapy (IGRT) with gold fiducial vaginal cuff markers for high-risk endometrial cancer

International Nuclear Information System (INIS)

Monroe, Alan T.; Peddada, Anuj V.; Pikaart, Dirk

2013-01-01

Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered

Characteristics of long-term consequences of acute radiation sickness

International Nuclear Information System (INIS)

Kovalenko, A.N.; Belyj, D.A.; Bebeshko, V.G.

2000-01-01

In persons who suffered from acute radiation sickness (ARS) as a result of the Chernobyl accident in course of time there are revealed the stochastic and non-stochastic effects of irradiation both in 'critical' and 'non-critical' organism systems. It is connected with maintenance of somatic mutation high level and steady changes in membranes subcellular structures, biomolecules as well as metabolic disturbances. Stable changes of hemopoietic and immune system indexes have to be considered as pre-pathological status with high hazard of stochastic effects development. Frequency rate of typical radiation cataracts (posterior subcapsular) is correlated with ARS severity degree; fundus oculi vessel pathology have essential weight in total eye pathology. Chronic radiation dermatitis is an important clinical problem being a long-term consequence of irradiation. It demands a constant attention in order to prevent trophic secondary skin lesions. Radiation damage of eye and skin as well as high frequency of chronic somatic diseases and neuropsychiatric disorders conditioned the high level of disablement in ARS-patients

Radiation in medicine: Origins, risks and aspirations.

Science.gov (United States)

Donya, Mohamed; Radford, Mark; ElGuindy, Ahmed; Firmin, David; Yacoub, Magdi H

2014-01-01

The use of radiation in medicine is now pervasive and routine. From their crude beginnings 100 years ago, diagnostic radiology, nuclear medicine and radiation therapy have all evolved into advanced techniques, and are regarded as essential tools across all branches and specialties of medicine. The inherent properties of ionizing radiation provide many benefits, but can also cause potential harm. Its use within medical practice thus involves an informed judgment regarding the risk/benefit ratio. This judgment requires not only medical knowledge, but also an understanding of radiation itself. This work provides a global perspective on radiation risks, exposure and mitigation strategies.

Medical interventional procedures--reducing the radiation risks

International Nuclear Information System (INIS)

Cousins, C.; Sharp, C.

2004-01-01

Over the last 40 years, the number of percutaneous interventional procedures using radiation has increased significantly, with many secondary care clinicians using fluoroscopically guided techniques. Many procedures can deliver high radiation doses to patients and staff, with the potential to cause immediate and delayed radiation effects. The challenge for interventionists is to maximize benefit, whilst minimizing radiation risk to patients and staff. Non-radiologist clinicians are often inadequately trained in radiation safety and radiobiology. However, clinical governance and legislation now requires a more rigorous approach to protecting patients and staff. Protection can be ensured, and risks can be controlled, by appropriate design, procurement and commissioning of equipment; quality assurance; and optimal operational technique, backed by audit. Interventionists need knowledge and skills to reduce the risks. Appropriate training should include awareness of the potential for radiation injury, equipment operational parameters, doses measurement and recording methods and dose reduction techniques. Clinical governance requires informed consent, appropriate patient counselling and follow-up

Medical interventional procedures--reducing the radiation risks

Energy Technology Data Exchange (ETDEWEB)

Cousins, C. E-mail: claire.cousins@addenbrookes.nhs.uk; Sharp, C

2004-06-01

Over the last 40 years, the number of percutaneous interventional procedures using radiation has increased significantly, with many secondary care clinicians using fluoroscopically guided techniques. Many procedures can deliver high radiation doses to patients and staff, with the potential to cause immediate and delayed radiation effects. The challenge for interventionists is to maximize benefit, whilst minimizing radiation risk to patients and staff. Non-radiologist clinicians are often inadequately trained in radiation safety and radiobiology. However, clinical governance and legislation now requires a more rigorous approach to protecting patients and staff. Protection can be ensured, and risks can be controlled, by appropriate design, procurement and commissioning of equipment; quality assurance; and optimal operational technique, backed by audit. Interventionists need knowledge and skills to reduce the risks. Appropriate training should include awareness of the potential for radiation injury, equipment operational parameters, doses measurement and recording methods and dose reduction techniques. Clinical governance requires informed consent, appropriate patient counselling and follow-up.

Cardiovascular risks associated with low dose ionizing particle radiation.

Directory of Open Access Journals (Sweden)

Xinhua Yan

Full Text Available Previous epidemiologic data demonstrate that cardiovascular (CV morbidity and mortality may occur decades after ionizing radiation exposure. With increased use of proton and carbon ion radiotherapy and concerns about space radiation exposures to astronauts on future long-duration exploration-type missions, the long-term effects and risks of low-dose charged particle irradiation on the CV system must be better appreciated. Here we report on the long-term effects of whole-body proton ((1H; 0.5 Gy, 1 GeV and iron ion ((56Fe; 0.15 Gy, 1GeV/nucleon irradiation with and without an acute myocardial ischemia (AMI event in mice. We show that cardiac function of proton-irradiated mice initially improves at 1 month but declines by 10 months post-irradiation. In AMI-induced mice, prior proton irradiation improved cardiac function restoration and enhanced cardiac remodeling. This was associated with increased pro-survival gene expression in cardiac tissues. In contrast, cardiac function was significantly declined in (56Fe ion-irradiated mice at 1 and 3 months but recovered at 10 months. In addition, (56Fe ion-irradiation led to poorer cardiac function and more adverse remodeling in AMI-induced mice, and was associated with decreased angiogenesis and pro-survival factors in cardiac tissues at any time point examined up to 10 months. This is the first study reporting CV effects following low dose proton and iron ion irradiation during normal aging and post-AMI. Understanding the biological effects of charged particle radiation qualities on the CV system is necessary both for the mitigation of space exploration CV risks and for understanding of long-term CV effects following charged particle radiotherapy.

Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

International Nuclear Information System (INIS)

McGuire, S.A.

1991-02-01

The chemical effects from acute exposures to uranium hexafluoride are compared to the nonstochastic effects from acute radiation doses of 25 rems to the whole body and 300 rems to the thyroid. The analysis concludes that an intake of about 10 mg of uranium in soluble form is roughly comparable, in terms of early effects, to an acute whole body dose of 25 rems because both are just below the threshold for significant nonstochastic effects. Similarly, an exposure to hydrogen fluoride at a concentration of 25 mg/m 3 for 30 minutes is roughly comparable because there would be no significant nonstochastic effects. For times t other than 30 minutes, the concentration C of hydrogen fluoride considered to have the same effect can be calculated using a quadratic equation: C = 25 mg/m 3 (30 min/t). The purpose of these analyses is to provide information for developing design and siting guideline based on chemical toxicity for enrichment plants using uranium hexafluoride. These guidelines are to be similar, in terms of stochastic health effects, to criteria in NRC regulations of nuclear power plants, which are based on radiation doses. 26 refs., 1 fig., 5 tabs

Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

Energy Technology Data Exchange (ETDEWEB)

McGuire, S.A.

1991-02-01

The chemical effects from acute exposures to uranium hexafluoride are compared to the nonstochastic effects from acute radiation doses of 25 rems to the whole body and 300 rems to the thyroid. The analysis concludes that an intake of about 10 mg of uranium in soluble form is roughly comparable, in terms of early effects, to an acute whole body dose of 25 rems because both are just below the threshold for significant nonstochastic effects. Similarly, an exposure to hydrogen fluoride at a concentration of 25 mg/m{sup 3} for 30 minutes is roughly comparable because there would be no significant nonstochastic effects. For times t other than 30 minutes, the concentration C of hydrogen fluoride considered to have the same effect can be calculated using a quadratic equation: C = 25 mg/m{sup 3} (30 min/t). The purpose of these analyses is to provide information for developing design and siting guideline based on chemical toxicity for enrichment plants using uranium hexafluoride. These guidelines are to be similar, in terms of stochastic health effects, to criteria in NRC regulations of nuclear power plants, which are based on radiation doses. 26 refs., 1 fig., 5 tabs.

Occupational radiation exposure risks: a review

Energy Technology Data Exchange (ETDEWEB)

Besar, Idris [PUSPATI, Selangor (Malaysia)

1984-06-01

This paper presents a review of the health risk as a result of exposure to ionizing radiation. A comparison of occupational risk among workers exposed to radiological and nonradiological harms are also presented. This comparison shows that radiation workers exposed to the current nuclear industry average of 3.4 mSv. per year are among the safest of all industry groupings.

Occupational radiation exposure risks: a review

International Nuclear Information System (INIS)

Idris Besar

1984-01-01

This paper presents a review of the health risk as a result of exposure to ionizing radiation. A comparison of occupational risk among workers exposed to radiological and nonradiological harms are also presented. This comparison shows that radiation workers exposed to the current nuclear industry average of 3.4 mSv. per year are among the safest of all industry groupings. (author)

Statins and the risk of acute pancreatitis: A population-based case-control study

DEFF Research Database (Denmark)

Thisted, Henriette; Jacobsen, Jacob; Munk, Estrid Muff

2006-01-01

BACKGROUND: Case reports have suggested that statins may cause acute pancreatitis. AIM: To examine if statins are associated with risk of acute pancreatitis. METHODS: We identified 2576 first-time admitted cases of acute pancreatitis from hospital discharge registers in three Danish counties, and......: Our findings speak against a strong causative effect of statins on the risk of acute pancreatitis, and may even indicate a mild protective effect....

Cancer risks after radiation exposures

International Nuclear Information System (INIS)

Voelz, G.L.

1980-01-01

A general overview of the effects of ionizing radiation on cancer induction is presented. The relationship between the degree of risk and absorbed dose is examined. Mortality from radiation-induced cancer in the US is estimated and percentages attributable to various sources are given

Antiradiation Antitoxin IgG : Immunological neutralization of Radiation Toxins at Acute Radiation Syndromes.

Science.gov (United States)

Popov, Dmitri; Maliev, Slava

Introduction: High doses of radiation induce apoptotic necrosis of radio-sensitive cells. Mild doses of radiation induce apoptosis or controlled programmed death of radio-sensitive cells with-out development of inflammation and formation of Radiation Toxins. Cell apoptotic necrosis initiates Radiation Toxins (RT)formation. Radiation Toxins play an important role as a trig-ger mechanism for inflammation development and cell lysis. If an immunotherapy approach to treatment of the acute radiation syndromes (ARS) were to be developed, a consideration could be given to neutralization of radiation toxins (Specific Radiation Determinants-SRD) by specific antiradiation antibodies. Therapeutic neutralization effects of the blocking anti-radiation antibodies on the circulated RT had been studied. Radiation Toxins were isolated from the central lymph of irradiated animals with Cerebrovascular(Cv ARS),Cardiovascular (Cr ARS),Gastrointestinal(Gi ARS) and Haemopoietic (Hp ARS) forms of ARS. To accomplish this objective, irradiated animals were injected with a preparation of anti-radiation immunoglobulin G (IgG) obtained from hyperimmune donors. Radiation-induced toxins that we call Specific Radiation Determinants (SRD) possess toxic (neurotoxic, haemotoxic) characteristics as well as specific antigenic properties. Depending on direct physiochemical radiation damage, they can induce development of many of the pathological processes associated with ARS. We have tested several specific hyperimmune IgG preparations against these radiation toxins and ob-served that their toxic properties were neutralized by the specific antiradiation IgGs. Material and Methods: A scheme of experiments was following: 1.Isolation of radiation toxins (RT) from the central lymph of irradiated animals with different form of ARS. 2.Transformation of a toxic form of the RT to a toxoid form of the RT. 3.Immunization of radiation naive animals. Four groups of rabbits were inoculated with a toxoid form of SRD

Acute Pancreatitis and Pancreatic Cancer Risk: A Nationwide Matched-cohort Study in Denmark

DEFF Research Database (Denmark)

Kirkegård, Jakob; Cronin Fenton, Deirdre; Heide-Jørgensen, Uffe

2018-01-01

. Pancreatic cancer risk was expressed as hazard ratios (HRs) with 95% CIs, calculated using the Cox proportional hazards model. Cox models were stratified by age, sex, and year of pancreatitis diagnosis and adjusted for alcohol- and smoking-related conditions, and Charlson Comorbidity Index score. Results We...... included 41,669 patients diagnosed with incident acute pancreatitis and 208,340 comparison individuals. Patients with acute pancreatitis had an increased risk of pancreatic cancer compared with the age- and sex-matched general population throughout the follow-up period. The risk decreased over time......Background & Aims Acute pancreatitis may be a risk factor for pancreatic cancer. However, findings from studies on this association are conflicting. We investigated the association between acute pancreatitis and increased risk of pancreatic cancer. Methods We conducted a nationwide, population...

The acute radiation syndrome: A study of ten cases and a review of the problem

Energy Technology Data Exchange (ETDEWEB)

Hempelmann, L.H.; Lisco, H.

1950-03-17

In this report ten cases of acute radiation syndrome are described resulting from two accidents occurring at the Los Alamos Scientific Laboratory of unique nature involving fissionable material. These cases are described in considerable detail. The report comprises ten sections. This volume, part II of the report, is comprised of sections entitled: (1) the Biological Basis for the Clinical Response seen in the Acute radiation Syndrome, (2) Clinical Signs and Symptoms, (3) Discussion of Hematological Findings, (4) Chemistry of the Blood and Urine, (5) Discussion of Pathological Findings, and (6) Reconsiderations of the Calculated Radiation Doses in Terms of the Observed Biological Response of the Patients. This report was prepared primarily for the clinician who is interested in radiation injuries and therefore emphasis has been placed on the correlation of clinical and pathological changes with the type of cytogenetic change known to be produced by ionizing radiation.

Study of radiation safety education practices in acute care Texas hospitals

International Nuclear Information System (INIS)

Lemley, A.A.; Hedl, J.J. Jr.; Griffin, E.E.

1987-01-01

A survey study was performed to assess the extent of radiation safety education and training in acute care Texas hospitals for radiologic technologists and other hospital personnel. The findings revealed a self-perceived need by hospital administrative personnel and were interpreted to suggest a quantitative need for increased radiation safety education for several classes of hospital personnel. The findings are discussed relative to potential certification requirements for technologists and implications for the training of other personnel

Radiation risk estimation

International Nuclear Information System (INIS)

Roberts, P.B.

1981-11-01

This report outlines the major publications between 1976 and 1981 that have contributed to the evolution of the way in which radiation risks (cancer and hereditary birth defects) are assessed. The publications include the latest findings of the UNSCEAR, BEIR and ICRP committees, epidemiological studies at low doses and new assessments of the doses received by the Japanese A-bomb survivors. This report is not a detailed critique of those publications, but it highlights the impact of their findings on risk assessment

Cranial radiation in childhood acute lymphocytic leukemia. Neuropsychologic sequelae

International Nuclear Information System (INIS)

Whitt, J.K.; Wells, R.J.; Lauria, M.M.; Wilhelm, C.L.; McMillan, C.W.

1984-01-01

A battery of neuropsychologic tests was administered ''blindly'' to 18 children with acute lymphocytic leukemia (ALL) who had been randomly assigned to treatment regimens with or without cranial radiation. These children were all in complete continuous remission for more than 3 1/2 years and were no longer receiving therapy. The results indicated no substantial differences between groups as a function of radiation therapy. However, decreased neuropsychologic performance was found when the entire sample was compared with population norms. These data do not support the hypothesis that cranial radiation therapy is responsible for the neuropsychologic sequelae seen in these survivors of ALL. Post hoc multiple regression analysis indicated that parental education levels accounted for more of the neuropsychologic variability seen in these children than other factors such as age at diagnosis, type of therapy, or sex of child

Thrombotic thrombocytopenic purpura and myoglobinuric acute renal failure following radiation therapy in a patient with polymyositis and cervical cancer

International Nuclear Information System (INIS)

Makino, Hirofumi; Nagake, Yoshio; Moriwaki, Kazuhiko; Hirakawa, Shuzo; Katayama, Takaaki; Yanai, Hiroyuki; Takahashi, Kiyoshi; Akagi, Tadaatsu; Ota, Zensuke

1995-01-01

A 73-year-old woman was admitted to receive radiation treatment for uterine cervical cancer, however a complex series of events ensued, leading to death. She developed an acute exacerbation of polymyositis complicated by thrombocytopenic purpura, rhabdomyolysis and acute renal failure. Radiation therapy may have produced an immune disturbance leading to the acute exacerbation of polymyositis. Auto-immune-mediated endothelial damage might have triggered a series of events leading to thrombotic thrombocytopenic purpura. Rhabdomyolysis seemed to be the main cause of acute renal failure. (author)

Thrombotic thrombocytopenic purpura and myoglobinuric acute renal failure following radiation therapy in a patient with polymyositis and cervical cancer

Energy Technology Data Exchange (ETDEWEB)

Makino, Hirofumi; Nagake, Yoshio; Moriwaki, Kazuhiko; Hirakawa, Shuzo; Katayama, Takaaki; Yanai, Hiroyuki; Takahashi, Kiyoshi; Akagi, Tadaatsu; Ota, Zensuke [Okayama Univ. (Japan). School of Medicine

1995-01-01

A 73-year-old woman was admitted to receive radiation treatment for uterine cervical cancer, however a complex series of events ensued, leading to death. She developed an acute exacerbation of polymyositis complicated by thrombocytopenic purpura, rhabdomyolysis and acute renal failure. Radiation therapy may have produced an immune disturbance leading to the acute exacerbation of polymyositis. Auto-immune-mediated endothelial damage might have triggered a series of events leading to thrombotic thrombocytopenic purpura. Rhabdomyolysis seemed to be the main cause of acute renal failure. (author).

Occupational radiation risk to radiologists

International Nuclear Information System (INIS)

Schuettmann, W.

1981-01-01

A review is given of the most important publications dealing with attempts to estimate the occupational radiation risk to radiologists by comparing data on their mortality from leukemia and other forms of cancer with respective data for other physicians who were not occupationally exposed to ionizing radiation. (author)

Risks associated with radiation: General information

International Nuclear Information System (INIS)

Baris, D.; Pomroy, C.; Chatterjee, R.M.

1995-07-01

Employers have a general responsibility to explain occupational risks to their workers. This document has been prepared to assist employers in this task. Employers should inform their workers about radiation risks associated with their work by: identifying the source(s) of radiation exposure; identifying the risk of health effects due to exposure to these sources, including the risk to the embryo and foetus of pregnant female workers; explaining the relationship between regulatory dose limits and the risk of health effects; and, explaining a worker's personal dose in terms of risk. This publication provides basic information on these subjects in a form that is clear and easy to understand. For further information, a list of suggested additional reading is included at the end of the text. (author). 15 refs., 5 tabs., 3 figs

Risks associated with radiation: General information

Energy Technology Data Exchange (ETDEWEB)

Baris, D; Pomroy, C; Chatterjee, R M

1995-07-01

Employers have a general responsibility to explain occupational risks to their workers. This document has been prepared to assist employers in this task. Employers should inform their workers about radiation risks associated with their work by: identifying the source(s) of radiation exposure; identifying the risk of health effects due to exposure to these sources, including the risk to the embryo and foetus of pregnant female workers; explaining the relationship between regulatory dose limits and the risk of health effects; and, explaining a worker`s personal dose in terms of risk. This publication provides basic information on these subjects in a form that is clear and easy to understand. For further information, a list of suggested additional reading is included at the end of the text. (author). 15 refs., 5 tabs., 3 figs.

Discussions about nuclear and radiation risk information communication

International Nuclear Information System (INIS)

Yang Bo; Wang Erqi; Peng Xianxun

2013-01-01

This paper described the definition and the objective of risk communication and the development of the risk communication research. It stated that how to establish a trustworthy relationship with public and the 8 aspects that should be done for keeping the relationship. With the analysis of the cognition and the influencing of the nuclear and radiation risk, this article figured out the factors which could influence the cognition of public on nuclear and radiation risk. Moreover, it explained the principles for enhancing the efficiency of the risk communication and the specific works in each phase of the risk communication. Finally, the suggestions for the development of the risk communication of the nuclear and radiation in China had been provided. (authors)

Radiation risk and science education

International Nuclear Information System (INIS)

Eijkelhof, H.M.C.

1996-01-01

Almost everywhere the topic of radioactivity is taught in the physics or chemistry classes of secondary schools. The question has been raised whether the common approach of teaching this topic would contribute to a better understanding of the risks of ionising radiation: and, if the answer is negative, how to explain and improve this situation? In a Dutch research programme which took almost ten years, answers to this question have been sought by means of analyses of newspaper reports, curriculum development, consultation with radiation experts, physics textbook analysis, interviews and questionnaires with teachers and pupils, class observations and curriculum development. Th main results of this study are presented and some recommendations given for science teaching and for communication with the public in general as regards radiation risk. (author)

Radiation in perspective applications, risks and protection

International Nuclear Information System (INIS)

1997-01-01

Everyone on earth is exposed to natural radiation. Radiation produced artificially is no different, either in kind or in effect, from that originating naturally. Although radiation has many beneficial applications, throughout medicine, industry and research, it can be harmful to human beings who must be adequately protected from unnecessary or excessive exposures. For this purpose, a thorough system of international principles and standards and stringent national legislations have been put in place. Yet radiation continues to be the subject of much public fear and controversy. This clearly written report, intended for the nonspecialist reader, aims to contribute to an enlightened debate on this subject by presenting the most up-to-date and authoritative material on sources, uses and affects of radiation, and ways in which people are protected from its risks. It discusses the development of radiation protection measures, its internationally agreed principles, and also addresses social and economic issues such as ethical questions, risk perceptions, risk comparisons, public participation in decision-making and the cost of protection. (author)

Risk factors for acute surgical site infections after lumbar surgery: a retrospective study.

Science.gov (United States)

Lai, Qi; Song, Quanwei; Guo, Runsheng; Bi, Haidi; Liu, Xuqiang; Yu, Xiaolong; Zhu, Jianghao; Dai, Min; Zhang, Bin

2017-07-19

Currently, many scholars are concerned about the treatment of postoperative infection; however, few have completed multivariate analyses to determine factors that contribute to the risk of infection. Therefore, we conducted a multivariate analysis of a retrospectively collected database to analyze the risk factors for acute surgical site infection following lumbar surgery, including fracture fixation, lumbar fusion, and minimally invasive lumbar surgery. We retrospectively reviewed data from patients who underwent lumbar surgery between 2014 and 2016, including lumbar fusion, internal fracture fixation, and minimally invasive surgery in our hospital's spinal surgery unit. Patient demographics, procedures, and wound infection rates were analyzed using descriptive statistics, and risk factors were analyzed using logistic regression analyses. Twenty-six patients (2.81%) experienced acute surgical site infection following lumbar surgery in our study. The patients' mean body mass index, smoking history, operative time, blood loss, draining time, and drainage volume in the acute surgical site infection group were significantly different from those in the non-acute surgical site infection group (p operative type in the acute surgical site infection group were significantly different than those in the non-acute surgical site infection group (p operative type, operative time, blood loss, and drainage time were independent predictors of acute surgical site infection following lumbar surgery. In order to reduce the risk of infection following lumbar surgery, patients should be evaluated for the risk factors noted above.

Radiation induced cancer: risk assessment and prevention

International Nuclear Information System (INIS)

Shore, R.E.

1984-01-01

A number of factors have to be considered in defining the cancer risk from ionizing radiation. These include the radiation sensitivity of the target tissue(s), the temporal pattern of risk, the shape of the dose-incidence curve, the effects of low dose rates, host susceptibility factors, and synergism with other environmental exposures. For the population as a whole the largest sources of radiation exposure are natural background radiation and medical/dental radiation. Radiation exposures in the medical field make up the largest volume of occupational exposures as well. Although new technologies offer opportunities to lower exposures, worker training, careful exposure monitoring with remedial feedback, and monitoring to prevent unnecessary radiodiagnostic procedures may be even more important means of reducing radiation exposure. Screening of irradiated populations can serve a useful preventive function, but only for those who have received very high doses

Gene expression in Catla catla (Hamilton) subjected to acute and protracted doses of gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Anbumani, S., E-mail: aquatox1982@gmail.com; Mohankumar, Mary N., E-mail: marynmk@gmail.com

2016-09-15

Highlights: • Gamma radiation induced up- and down- regulation of cell cycle genes. • Protracted dose-rate induced gene up-regulation to facilitate cell survival. • bcl-2 gene facilitates repair at protracted dose and cell death at acute exposures. • gadd45α, cdk1 and bcl-2 genes work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells. - Abstract: Studies on transcriptional modulation after gamma radiation exposure in fish are limited. Cell cycle perturbations and expression of apoptotic genes were investigated in the fish, Catla catla after acute and protracted exposures to gamma radiation over a 90 day period. Significant changes in gene expression were observed between day 1 and 90 post-exposure. Gamma radiation induced a significant down-regulation of target genes gadd45α, cdk1 and bcl-2 from day 1 to day 3 after protracted exposure, whereas it persists till day 6 upon acute exposure. From day 12 onwards, Gadd45α, cdk1 and bcl-2 genes were up-regulated following protracted exposure, indicating DNA repair, cell-cycle arrest and apoptosis. There exists a linear correlation between these genes (gadd45α – r = 0.85, p = 0.0073; cdk1 – r = 0.86, p = 0.0053; bcl-2 – r = 0.89, p = 0.0026) at protracted exposures. This is the first report on the dual role of bcl-2 gene in fish exposed to acute and protracted radiation and correlation among the aforementioned genes that work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells.

Gene expression in Catla catla (Hamilton) subjected to acute and protracted doses of gamma radiation

International Nuclear Information System (INIS)

Anbumani, S.; Mohankumar, Mary N.

2016-01-01

Highlights: • Gamma radiation induced up- and down- regulation of cell cycle genes. • Protracted dose-rate induced gene up-regulation to facilitate cell survival. • bcl-2 gene facilitates repair at protracted dose and cell death at acute exposures. • gadd45α, cdk1 and bcl-2 genes work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells. - Abstract: Studies on transcriptional modulation after gamma radiation exposure in fish are limited. Cell cycle perturbations and expression of apoptotic genes were investigated in the fish, Catla catla after acute and protracted exposures to gamma radiation over a 90 day period. Significant changes in gene expression were observed between day 1 and 90 post-exposure. Gamma radiation induced a significant down-regulation of target genes gadd45α, cdk1 and bcl-2 from day 1 to day 3 after protracted exposure, whereas it persists till day 6 upon acute exposure. From day 12 onwards, Gadd45α, cdk1 and bcl-2 genes were up-regulated following protracted exposure, indicating DNA repair, cell-cycle arrest and apoptosis. There exists a linear correlation between these genes (gadd45α – r = 0.85, p = 0.0073; cdk1 – r = 0.86, p = 0.0053; bcl-2 – r = 0.89, p = 0.0026) at protracted exposures. This is the first report on the dual role of bcl-2 gene in fish exposed to acute and protracted radiation and correlation among the aforementioned genes that work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells.

Hematological parameters after acute radiation injury

International Nuclear Information System (INIS)

Hirashima, Kunitake

1989-01-01

According to clinical experiences of radiation accidents during the past two decades, utilization of measured hematologic changes as a direcrt indicator of the severity of radiation injury provides important information for diagnosis and prognostic evaluation in individual cases. Hematologic changes can be described in terms of prognostic categories based on the possible outcome of the acute radiation syndrome. The five categories suggested by Wald according to the grade of severity. By the actual application of this category to our experience of the 1971 Chiba accident of exposure to irridium 192, it was proved that the estimated dose was well correlated to the value by cytogenetic analysis and physical estimation used of thermo-luminescence phenomena. In hematological parameters, a decrease of lymphocytes occurs whithin 24 hours after the exposure. The level of this early lymphopenia is regarded as one of the best indicators of severity of radiation injury. For the decision of therapeutic procedures, however, the total granulocyte count and platelet count are more valuable to exclude severe infection and bleeding symptoms occurred one month after the exposure. The limitation of the approach by hematologic data must exist in the case exposed in a non-uniform fashion. To overwhelm this difficulty, the application of rapid marrow scanning by short-lived RI such as 52 Fe is expected and the bone marrow imaging by magnetic resonance studies is more exciting. For more sensitive and technically easy-drived methods detecting hematologic injury, our new method of detecting micro-nucleus in polychromatic erythroblasts from cultured erythroid colonies from peripheral blood is now developing. Preliminary data have shown the sensitivity of this method is comparable to the cytogenetic study of pheripheral lymphocytes. (author)

Granulocyte Colony-Stimulating Factor in the Treatment of Acute Radiation Syndrome: A Concise Review

Czech Academy of Sciences Publication Activity Database

Hofer, Michal; Pospíšil, Milan; Komůrková, Denisa; Hoferová, Zuzana

2014-01-01

Roč. 19, č. 4 (2014), s. 4770-4778 ISSN 1420-3049 R&D Projects: GA ČR(CZ) GAP303/11/0128 Institutional support: RVO:68081707 Keywords : granulocyte colony-stimulating factor * radiation accident s * acute radiation syndrome Subject RIV: BO - Biophysics Impact factor: 2.416, year: 2014

Diagnostic criterions of the postradiation encephalopathy in remote period of the acute radiation syndrome

International Nuclear Information System (INIS)

Nyagu, A.I.; Loganovskij, K.N.; Vashchenko, E.A.

1998-01-01

Development of post-radiation encephalopathy diagnostic criteria on the base of neuro psychic, neuro- and psychofisiological research in patients who suffered with acute radiation disease after Chernobyl catastrophe was the aim of this work. 110 persons of 20-75 years age were investigated. 55 refs., 6 tab., 6 figs

DNA copy number analysis from mice with radiation-induced acute myeloid leukemia

Data.gov (United States)

National Aeronautics and Space Administration — Certain mouse strains such as CBA C3H and RFM have high incidence of radiation-induced acute myeloid leukemia (AML). The data in this series wer generated by using...

Interaction between radiation and other breast cancer risk factors

International Nuclear Information System (INIS)

Boice, J.D. Jr.; Stone, B.J.

1978-01-01

A follow-up study was conducted of 1764 women institutionalized for pulmonary tuberculosis between 1930 and 1954. Among 1047 women exposed to fluoroscopic chest X-rays during air collapse therapy of the lung, an excess of breast cancer was observed and previously reported (41 cases observed versus 23.3 expected). Among 717 comparison patients who received other treatments, no excess breast cancer risk was apparent (15 cases observed versus 14.1 expected). To determine whether breast cancer risk factors modify the carcinogenic effect of radiation, analyses were performed evaluating the interaction of radiation with indicators of breast cancer risk. The greatest radiation risk was found when radiation exposure occurred just before and during menarche. Similarly, exposures during first pregnancy appeared substantially more hazardous than exposures occurring before or after first pregnancy, suggesting that the condition of the breast at the time of pregnancy modifies the effect of radiation in such a way as to enhance the risk. Age at menopause did not appear to influence the risk of radiation exposure. Other than radiation, benign breast disease was the most significant breast cancer risk indicator. Benign breast disease was not seen to modify the effect of radiation exposure; however, excessive radiation exposure might have increased the incidence of benign breast disease, complicating the interaction analysis. Because of the uncertainty due to small-number sampling variation, these study results will require confirmation by a larger series. They do, however, suggest that stages when breast tissue undergoes high mitotic activity, e.g. menarche and pregnancy, are times of special vulnerability to the harmful effects of ionizing radiation

Metformin-associated risk of acute dialysis in patients with type 2 diabetes

DEFF Research Database (Denmark)

Carlson, Nicholas; Hommel, Kristine; Olesen, Jonas Bjerring

2016-01-01

. The metformin-associated 1-year risk of acute dialysis was increased by 50.3 per 100 000 (95% CI, 7.9-88.6), corresponding to a risk ratio of 1.53 (95% CI, 1.06-2.23), and a number needed to harm of 1988, thus providing evidence of potential concerns pertaining to the increasing use of metformin.......Recent guidelines governing anti-diabetic medications increasingly advocate metformin as first-line therapy in all patients with type 2 diabetes. However, metformin could be associated with increased risk of acute kidney injury (AKI), acute dialysis and lactate acidosis in marginal patients....... In a retrospective nationwide cohort study, a total of 168 443 drug-naïve patients with type 2 diabetes ≥50 years, initiating treatment with either metformin or sulphonyl in Denmark between 2000 and 2012 were included in this study (70.7% initiated treatment with metformin); calculation of 1-year risk of acute...

Quantitative risk in radiation protection standards

International Nuclear Information System (INIS)

Bond, V.P.

1978-01-01

The bases for developing quantitative assessment of exposure risks in the human being, and the several problems that accompany the assessment and introduction of the risk of exposure to high and low LET radiation into radiation protection, will be evaluated. The extension of the pioneering radiation protection philosophies to the control of other hazardous agents that cannot be eliminated from the environment will be discussed, as will the serious misunderstandings and misuse of concepts and facts that have inevitably surrounded the application to one agent alone, of the protection philosophy that must in time be applied to a broad spectrum of potentially hazardous agents. (orig.) [de

Medulloblastoma: Conventional Radiation Therapy in Comparison to Chemo Radiation Therapy in The Post-operative Treatment of High-Risk Patients

International Nuclear Information System (INIS)

Abd El-Aal, H.H.; Mokhtar, M.M.; Habib, E.E.; El-Kashef, A.T.; Fahmy, E.S.

2005-01-01

The aim of this study is to assess treatment results of 48 pediatric high-risk medulloblastoma cases that were treated by surgery, radiotherapy with or without chemotherapy. The impact of adjuvant combination chemotherapy on treatment results will be assessed. Forty-eight cases of pediatric high-risk medulloblastoma treated from July 2001 to July 2004 were randomized into two groups. The first (group I) included 21 patients who received postoperative craniospinal radiation therapy (36 Gy + boost 20 Gy to the posterior fossa). The second (group II) included 27 cases who received postoperative combination cranio-spinal radiation therapy (with the same dose as the first group) and chemotherapy (vincristine, etoposide, cisplatin). Both groups were compared as regards overall survival (OS), disease free survival (DFS), response rate and treatment toxicity. In-group I, complete remission (CR) was achieved in 71.4% of the cases; partial remission (PR) in 14.3% of the patients; stationary disease (SD) in 14.3% and none of the cases suffered from progressive disease. The three year OS was 69.5% and the three-year OFS was 61.3%. In-group II, CR was achieved in 59.3% of the cases; PR in 3.7%; SO in 3.7% and PO in 37.3% of the cases. The three-year OS was 48.4% and the 3-year OFS was 48.9%. Regarding acute treatment toxicity in group I, nine patients (31.5%) developed grade I myelo-suppression and seven cases (24.5%) developed grade II myelo-suppression with three to five days treatment interruption. Whereas in group II, 13 patients (45.5%) developed grade I myelosuppression and seven cases (24.5%) developed grade II myelo-suppression requiring interruption of treatment for a period ranging from five to seven days with spontaneous recovery. In group I no other acute toxicity was recognized, whereas in group II other toxicities related to chemotherapy were noticed. For example, three patients (II %) developed peripheral neuritis during the course of treatment and two patients

A case of acutely developed delayed radiation myelopathy

International Nuclear Information System (INIS)

Hayashi, Shintaro; Amari, Masakuni; Fukuda, Toshio; Okamoto, Koichi

2002-01-01

A 66-year-old man with a history of hypertension received radiation therapy on his neck at age 61 because of laryngeal cancer (T1bN0M0). Five years after the radiation, he acutely developed dysuria, tetraparesis and dissociated sensory disturbances below bilateral Th4 level. T2 weighted MRI showed a high signal lesion affecting the central area of the spinal cord extending from C1 to C7. On the second clinical day, he developed respiratory arrest and was ventilated. The cerebrospinal fluid contained 20/mm 3 (monocyte 15, neutorophil 5) white cells; protein was 52.5 mg/dl; IgG index 0.54; Q albumin was 9.6; tests for oligoclonal band and myelin basic protein were negative; a culture yielded no microorganism. He was treated with steroids and supportive measures without improvement, and died of a sudden cardiac arrest on the 8th clinical day. postmortem examination confirmed conspicuous focal spongy changes with many axonal swellings, especially in the posterior and lateral columns at cervical and Th1 levels. The pathological findings were considered to be compatible with those of delayed radiation myelopathy (DRM). In the anterior horn of the cervical cord there were lesions of diffuse racification and the proliferation of small vessels. There were no findings of hyaline vascular changes, infarction or metastasis of laryngeal cancer at the spinal cord. It is considered that hyperintensity of signals on T2-weighted may originate from racification and proliferation of small vessels in the gray matter, and these pathological changes would be intimately associated with the severe neurologic morbidity of this patient. Acute development of neurological findings and the pathological changes in the gray matter of the spinal cord are rare manifestations of DRM. (author)

Factors that modify risks of radiation-induced cancer

International Nuclear Information System (INIS)

Fabrikant, J.I.

1988-11-01

The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors)

Medical management of the acute radiation syndrome

International Nuclear Information System (INIS)

Lopez, M.; Martin, M.

2011-01-01

The acute radiation syndrome (ARS) occurs after whole-body or significant partial-body irradiation (typically at a dose of >1 Gy). ARS can involve the hematopoietic, cutaneous, gastrointestinal and the neurovascular organ systems either individually or in combination. There is a correlation between the severity of clinical signs and symptoms of ARS and radiation dose. Radiation induced multi-organ failure (MOF) describes the progressive dysfunction of two or more organ systems over time. Radiation combined injury (RCI) is defined as radiation injury combined with blunt or penetrating trauma, burns, blast, or infection. The classic syndromes are: hematopoietic (doses >2 - 3 Gy), gastrointestinal (doses 5- 12 Gy) and cerebrovascular syndrome (doses 10 - 20 Gy). There is no possibility to survive after doses >10 - 12 Gy. The Phases of ARS are - prodromal: 0 - 2 days from exposure, latent: 2 - 20 days, and manifest illness: 21 - 60 days from exposure. Granulocyte-colony stimulating factor (G-CSF) at a dose of 5 micro g/kg body weight per day subcutaneously has been recommended as treatment of neutropenia, and antibiotics, antiviral and antifungal agents for prevention or treatment of infections. If taken within the first hours of contamination, stable iodine in the form of nonradioactive potassium iodide (KI) saturates iodine binding sites within the thyroid and inhibits incorporation of radioiodines into the gland. Finally, if severe aplasia persists under cytokines for more than 14 days, the possibility of a hematopoietic stem cell (HSC) transplantation should be evaluated. This review will focus on the clinical aspects of the ARS, using the European triage system (METREPOL) to evaluate the severity of radiation injury, and scoring groups of patients for the general and specific management of the syndrome. (authors)

The biological effects of exposure to ionising radiation

International Nuclear Information System (INIS)

Higson, D.J.

2016-01-01

Scenarios for exposure to ionising radiation range from natural background radiation (chronic) to the explosions of atomic bombs (acute), with some medical, industrial and research exposures lying between these extremes. Biological responses to radiation that predominate at high doses incurred at high dose rates are different from those that predominate at low doses and low dose rates. Single doses from bomb explosions ranged up to many thousand mGy. Acute doses greater than about 1000 mGy cause acute radiation syndrome (ARS). Below this threshold, radiation has a variety of potential latent health effects: Change to the incidence of cancer is the most usual subject of attention but change to longevity may be the best overall measure because decreased incidences of non-cancer mortality have been observed to coincide with increased incidence of cancer mortality. Acute doses greater than 500 mGy cause increased risks of cancer and decreased life expectancy. For doses less than 100 mGy, beneficial overall health effects ('radiation hormesis') have been observed. At the other end of the spectrum, chronic exposure to natural radiation has occurred throughout evolution and is necessary for the normal life and health of current species. Dose rates greater than the present global average of about 2 mGy per year have either no discernible health effect or beneficial health effects up to several hundred mGy per year. It is clearly not credible that a single health effects model -- such as the linear no-threshold (LNT) model of risk estimation -- could fit all latent health effects. A more realistic model is suggested.

Evaluating shielding effectiveness for reducing space radiation cancer risks

International Nuclear Information System (INIS)

Cucinotta, Francis A.; Kim, Myung-Hee Y.; Ren, Lei

2006-01-01

We discuss calculations of probability distribution functions (PDF) representing uncertainties in projecting fatal cancer risk from galactic cosmic rays (GCR) and solar particle events (SPE). The PDFs are used in significance tests for evaluating the effectiveness of potential radiation shielding approaches. Uncertainties in risk coefficients determined from epidemiology data, dose and dose-rate reduction factors, quality factors, and physics models of radiation environments are considered in models of cancer risk PDFs. Competing mortality risks and functional correlations in radiation quality factor uncertainties are included in the calculations. We show that the cancer risk uncertainty, defined as the ratio of the upper value of 95% confidence interval (CI) to the point estimate is about 4-fold for lunar and Mars mission risk projections. For short-stay lunar missions ( 180d) or Mars missions, GCR risks may exceed radiation risk limits that are based on acceptable levels of risk. For example, the upper 95% CI exceeding 10% fatal risk for males and females on a Mars mission. For reducing GCR cancer risks, shielding materials are marginally effective because of the penetrating nature of GCR and secondary radiation produced in tissue by relativistic particles. At the present time, polyethylene or carbon composite shielding cannot be shown to significantly reduce risk compared to aluminum shielding based on a significance test that accounts for radiobiology uncertainties in GCR risk projection

Assessment of the radiation risk from diagnostic radiology

International Nuclear Information System (INIS)

Streffer, C.; Mueller, W.U.

1995-01-01

In any assessment of radiation risks from diagnostic radiology the main concern is the possible induction of cancer. It now appears to be beyond all doubt that ionizing rays invite the development of cancer in humans. The radiation doses encountered in diagnostic radiology generally vary from 1 to 50 mSv. For this dose range, no measured values are available to ascertain cancer risks from ionizing rays. The effects of such doses must therefore be extrapolated from higher dose levels under consideration of given dose-effect relationships. All relevant figures for diagnostic X-ray measures are therefore mathematically determined approximate values. The stochastic radiation risk following non-homogeneous radiation exposure is assessed on the basis of the effective dose. This dose was originally introduced to ascertain the risk from radioactive substances incorporated at the working place. A secondary intention was to trigger further developmental processes in radiation protection. Due to the difficulties previously outlined and the uncertainties surrounding the determination and assessment of the effective dose from diagnostic X-ray procedures, this dose should merely be used for technological refinements and comaprisons of examination procedures. It appears unreasonable that the effective doses determined for the individual examinations are summed up to obtain a collective effective dose and to multiply this with a risk factor so as to give an approximation of the resulting deaths from cancer. A reasonable alternative is to inform patients subjected to X-ray examinations about the associated radiation dose and to estimate form this the magnitude of the probable radiation risk. (orig./MG) [de

Cancer risks following diagnostic and therapeutic radiation exposure in children

Energy Technology Data Exchange (ETDEWEB)

Kleinerman, Ruth A. [National Institutes of Health, Division of Cancer Epidemiology and Genetics, National Cancer Institute, EPS 7044, Rockville, MD (United States)

2006-09-15

The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life. (orig.)

Cancer risks following diagnostic and therapeutic radiation exposure in children

International Nuclear Information System (INIS)

Kleinerman, Ruth A.

2006-01-01

The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life. (orig.)

Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

Science.gov (United States)

Bednarz, Bryan; Besemer, Abigail

2017-09-01

The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.

Two cases of acute leukemia developed after therapeutic radiation for malignant tumors

International Nuclear Information System (INIS)

Takahashi, Naoki; Matsuo, Kakaru; Yamaguchi, Hiroshi; Tsuno, Sumio; Toyoda, Shigeki

1978-01-01

Report was made as to two cases of acute leukemia developed after therapeutic radiation for malignant tumors. Both cases were exposed to atomic-bomb at the places 4 and 3 km far from the center of explosion, and they did not suffer from injuries and acute symptoms due to radiation. Case 1. -A 78 year old man had a mass in a right hypogastric region in April of 1975. In March of 1976, he received laparotomy and was diagnosed as malignant schwannoma. He received radiation therapy with 4,600 R and MFC therapy. In February of 1977, a clinical diagnosis of erythroleukemia was made according to the findings by bone marrow puncture, and he died in March. Postmortem examination revealed that main lesions were malignant schwannoma, its metastases, and leukemia. Case 2. -A 51 year old woman had a finger-tip sized tumor in the left breast in November of 1965, and had a radical operation on the basis of a diagnosis of comedo sarcoma. After that she received 60 Co irradiation with 18,800 R, and she was admitted in December of 1971, because she was suspected of having leukemia. She died in January of 1972. Postmortem examination revealed acute myelocytic leukemia. It is suspected that the onset of erythroleukemia within one year after irradiation would be influenced by MFC therapy in addition to radiotherapy. It was thought that leukemia in Case 2 was influenced by radiotherapy rather than atomic-bomb radioactivity. (Serizawa, K.)

Breast Intensity-Modulated Radiation Therapy Reduces Time Spent With Acute Dermatitis for Women of All Breast Sizes During Radiation

International Nuclear Information System (INIS)

Freedman, Gary M.; Li Tianyu; Nicolaou, Nicos; Chen Yan; Ma, Charlie C.-M.; Anderson, Penny R.

2009-01-01

Purpose: To study the time spent with radiation-induced dermatitis during a course of radiation therapy for breast cancer in women treated with conventional or intensity-modulated radiation therapy (IMRT). Methods and Materials: The study population consisted of 804 consecutive women with early-stage breast cancer treated with breast-conserving surgery and radiation from 2001 to 2006. All patients were treated with whole-breast radiation followed by a boost to the tumor bed. Whole-breast radiation consisted of conventional wedged photon tangents (n = 405) earlier in the study period and mostly of photon IMRT (n = 399) in later years. All patients had acute dermatitis graded each week of treatment. Results: The breakdown of the cases of maximum acute dermatitis by grade was as follows: 3%, Grade 0; 34%, Grade 1; 61%, Grade 2; and 2%, Grade 3. The breakdown of cases of maximum toxicity by technique was as follows: 48%, Grade 0/1, and 52%, Grade 2/3, for IMRT; and 25%, Grade 0/1, and 75%, Grade 2/3, for conventional radiation therapy (p < 0.0001). The IMRT patients spent 82% of weeks during treatment with Grade 0/1 dermatitis and 18% with Grade 2/3 dermatitis, compared with 29% and 71% of patients, respectively, treated with conventional radiation (p < 0.0001). Furthermore, the time spent with Grade 2/3 toxicity was decreased in IMRT patients with small (p = 0.0015), medium (p < 0.0001), and large (p < 0.0001) breasts. Conclusions: Breast IMRT is associated with a significant decrease both in the time spent during treatment with Grade 2/3 dermatitis and in the maximum severity of dermatitis compared with that associated with conventional radiation, regardless of breast size.

Risks and management of radiation exposure.

Science.gov (United States)

Yamamoto, Loren G

2013-09-01

High-energy ionizing radiation is harmful. Low-level exposure sources include background, occupational, and medical diagnostics. Radiation disaster incidents include radioactive substance accidents and nuclear power plant accidents. Terrorism and international conflict could trigger intentional radiation disasters that include radiation dispersion devices (RDD) (a radioactive dirty bomb), deliberate exposure to industrial radioactive substances, nuclear power plant sabotage, and nuclear weapon detonation. Nuclear fissioning events such as nuclear power plant incidents and nuclear weapon detonation release radioactive fallout that include radioactive iodine 131, cesium 137, strontium 90, uranium, plutonium, and many other radioactive isotopes. An RDD dirty bomb is likely to spread only one radioactive substance, with the most likely substance being cesium 137. Cobalt 60 and strontium 90 are other RDD dirty bomb possibilities. In a radiation disaster, stable patients should be decontaminated to minimize further radiation exposure. Potassium iodide (KI) is useful for iodine 131 exposure. Prussian blue (ferric hexacyanoferrate) enhances the fecal excretion of cesium via ion exchange. Ca-DTPA (diethylenetriaminepentaacetic acid) and Zn-DTPA form stable ionic complexes with plutonium, americium, and curium, which are excreted in the urine. Amifostine enhances chemical and enzymatic repair of damaged DNA. Acute radiation sickness ranges in severity from mild to lethal, which can be assessed by the nausea/vomiting onset/duration, complete blood cell count findings, and neurologic symptoms.

Environmental radiation standards and risk limitation

International Nuclear Information System (INIS)

Kocher, D.C.

1987-01-01

The Environmental Protection Agency and Nuclear Regulatory Commission have established environmental radiation standards for specific practices which correspond to limits on risk to the public that vary by several orders of magnitude and often are much less than radiation risks that are essentially unregulated, e.g., risks from radon in homes. This paper discusses a proposed framework for environmental radiation standards that would improve the correspondence with limitation of risk. This framework includes the use of limits on annual effective dose equivalent averaged over a lifetime, rather than limits on dose equivalent to whole body or any organ for each year of exposure, and consideration of exposures of younger age groups as well as adults; limits on annual effective dose equivalent averaged over a lifetime no lower than 0.25 mSv (25 mrem) per practice; maintenance of all exposures as low as reasonably achievable (ALARA); and establishment of a generally applicable de minimis dose for public exposures. Implications of the proposed regulatory framework for the current system of standards for limiting public exposures are discussed. 20 refs

Successful Mitigation of Delayed Intestinal Radiation Injury Using Pravastatin is not Associated with Acute Injury Improvement or Tumor Protection

International Nuclear Information System (INIS)

Haydont, Valerie; Gilliot, Olivier; Rivera, Sofia; Bourgier, Celine; Francois, Agnes; Aigueperse, Jocelyne; Bourhis, Jean; Vozenin-Brotons, Marie-Catherine

2007-01-01

Purpose: To investigate whether pravastatin mitigates delayed radiation-induced enteropathy in rats, by focusing on the effects of pravastatin on acute cell death and fibrosis according to connective tissue growth factor (CTGF) expression and collagen inhibition. Methods and Materials: Mitigation of delayed radiation-induced enteropathy was investigated in rats using pravastatin administered in drinking water (30 mg/kg/day) 3 days before and 14 days after irradiation. The ileum was irradiated locally after surgical exteriorization (X-rays, 19 Gy). Acute apoptosis, acute and late histologic alterations, and late CTGF and collagen deposition were monitored by semiquantitative immunohistochemistry and colorimetric staining (6 h, 3 days, 14 days, 15 weeks, and 26 weeks after irradiation). Pravastatin antitumor action was studied in HT-29, HeLa, and PC-3 cells by clonogenic cell survival assays and tumor growth delay experiments. Results: Pravastatin improved delayed radiation enteropathy in rats, whereas its benefit in acute and subacute injury remained limited (6 h, 3 days, and 14 days after irradiation). Delayed structural improvement was associated with decreased CTGF and collagen deposition but seemed unrelated to acute damage. Indeed, the early apoptotic index increased, and severe subacute structural damage occurred. Pravastatin elicited a differential effect, protecting normal intestine but not tumors from radiation injury. Conclusion: Pravastatin provides effective protection against delayed radiation enteropathy without interfering with the primary antitumor action of radiotherapy, suggesting that clinical transfer is feasible

Radiation risk education program - local

International Nuclear Information System (INIS)

Bushong, S.C.; Archer, B.R.

1980-01-01

This article points out the lack of knowledge by the general public and medical profession concerning the true risks of radiation exposure. The author describes an educational program which can be implemented at the local level to overcome this deficiency. The public must understand the enormous extent of benefit derived from radiation applications in our society

A phase III randomized, placebo-controlled, double-blind study of misoprostol rectal suppositories to prevent acute radiation proctitis in patients with prostate cancer

International Nuclear Information System (INIS)

Hille, Andrea; Schmidberger, Heinz; Hermann, Robert M.; Christiansen, Hans; Saile, Bernhard; Pradier, Olivier; Hess, Clemens F.

2005-01-01

Purpose: Acute radiation proctitis is the most relevant complication of pelvic radiation and is still mainly treated supportively. Considering the negative impact of acute proctitis symptoms on patients' daily activities and the potential relationship between the severity of acute radiation injury and late damage, misoprostol was tested in the prevention of acute radiation-induced proctitis. Methods and Materials: A total of 100 patients who underwent radiotherapy for prostate cancer were entered into this phase III randomized, placebo-controlled, double-blind study with misoprostol or placebo suppositories. Radiation-induced toxicity was evaluated weekly during radiotherapy using the Common Toxicity Criteria. Results: Between the placebo and the misoprostol groups, no significant differences in proctitis symptoms occurred: 76% of patients in each group had Grade 1 toxicity, and 26% in the placebo group and 36% in the misoprostol group had Grade 2 toxicity. No differences were found in onset or symptom duration. Comparing the peak incidence of patients' toxicity symptoms, significantly more patients experienced rectal bleeding in the misoprostol group (p = 0.03). Conclusion: Misoprostol given as a once-daily suppository did not decrease the incidence and severity of radiation-induced acute proctitis and may increase the incidence of acute bleeding

Radiation risk - historical perspective and current issues

Energy Technology Data Exchange (ETDEWEB)

Kellerer, Albrecht M. [Strahlenbiologisches Institut, Ludwig-Maximilians-Universitaet, Munich, Germany and Institute for Radiation Biology, GSF-National Research Center for Environment and Health, Neuherberg (Germany)

2002-09-01

The assessment of radiation risk needs to be seen against the background of a historical development that has reversed the initial belief in a general beneficial effect of radiation to apprehension and fear. Numerical risk estimates are, today, based on large epidemiological studies, and the observations on the A-bomb survivors are outlined as the primary source of information. Since the epidemiological findings are obtained from relatively high radiation exposures, extrapolations are required to the much lower doses that are relevant to radiation protection. The evolution of extrapolation procedures up to current attempts at mechanistic modelling is outlined, and some of the open issues are reviewed. (author)

Radiation risk - historical perspective and current issues

International Nuclear Information System (INIS)

Kellerer, Albrecht M.

2002-01-01

The assessment of radiation risk needs to be seen against the background of a historical development that has reversed the initial belief in a general beneficial effect of radiation to apprehension and fear. Numerical risk estimates are, today, based on large epidemiological studies, and the observations on the A-bomb survivors are outlined as the primary source of information. Since the epidemiological findings are obtained from relatively high radiation exposures, extrapolations are required to the much lower doses that are relevant to radiation protection. The evolution of extrapolation procedures up to current attempts at mechanistic modelling is outlined, and some of the open issues are reviewed. (author)

Systematic review on physician's knowledge about radiation doses and radiation risks of computed tomography

International Nuclear Information System (INIS)

Krille, Lucian; Hammer, Gael P.; Merzenich, Hiltrud; Zeeb, Hajo

2010-01-01

Background: The frequent use of computed tomography is a major cause of the increasing medical radiation exposure of the general population. Consequently, dose reduction and radiation protection is a topic of scientific and public concern. Aim: We evaluated the available literature on physicians' knowledge regarding radiation dosages and risks due to computed tomography. Methods: A systematic review in accordance with the Cochrane and PRISMA statements was performed using eight databases. 3091 references were found. Only primary studies assessing physicians' knowledge about computed tomography were included. Results: 14 relevant articles were identified, all focussing on dose estimations for CT. Overall, the surveys showed moderate to low knowledge among physicians concerning radiation doses and the involved health risks. However, the surveys varied considerably in conduct and quality. For some countries, more than one survey was available. There was no general trend in knowledge in any country except a slight improvement of knowledge on health risks and radiation doses in two consecutive local German surveys. Conclusions: Knowledge gaps concerning radiation doses and associated health risks among physicians are evident from published research. However, knowledge on radiation doses cannot be interpreted as reliable indicator for good medical practice.

Radiation and society: Comprehending radiation risk. V. 3. Proceedings of an international conference

International Nuclear Information System (INIS)

1997-01-01

This IAEA international conference on Radiation and Society was the first major international meeting devoted to the comprehension of radiation risk, public attitude towards radiation risk and hazards encountered by the general public in contaminated areas. Volume three of the proceedings contains the speeches, ten introductory papers, summaries of the technical discussion sessions, the key note paper on uncertainties in the health impact of environmental pollutants. Refs, figs, tabs

Ataxia Telangiectasia–Mutated Gene Polymorphisms and Acute Normal Tissue Injuries in Cancer Patients After Radiation Therapy: A Systematic Review and Meta-analysis

International Nuclear Information System (INIS)

Dong, Lihua; Cui, Jingkun; Tang, Fengjiao; Cong, Xiaofeng; Han, Fujun

2015-01-01

Purpose: Studies of the association between ataxia telangiectasia–mutated (ATM) gene polymorphisms and acute radiation injuries are often small in sample size, and the results are inconsistent. We conducted the first meta-analysis to provide a systematic review of published findings. Methods and Materials: Publications were identified by searching PubMed up to April 25, 2014. Primary meta-analysis was performed for all acute radiation injuries, and subgroup meta-analyses were based on clinical endpoint. The influence of sample size and radiation injury incidence on genetic effects was estimated in sensitivity analyses. Power calculations were also conducted. Results: The meta-analysis was conducted on the ATM polymorphism rs1801516, including 5 studies with 1588 participants. For all studies, the cut-off for differentiating cases from controls was grade 2 acute radiation injuries. The primary meta-analysis showed a significant association with overall acute radiation injuries (allelic model: odds ratio = 1.33, 95% confidence interval: 1.04-1.71). Subgroup analyses detected an association between the rs1801516 polymorphism and a significant increase in urinary and lower gastrointestinal injuries and an increase in skin injury that was not statistically significant. There was no between-study heterogeneity in any meta-analyses. In the sensitivity analyses, small studies did not show larger effects than large studies. In addition, studies with high incidence of acute radiation injuries showed larger effects than studies with low incidence. Power calculations revealed that the statistical power of the primary meta-analysis was borderline, whereas there was adequate power for the subgroup analysis of studies with high incidence of acute radiation injuries. Conclusions: Our meta-analysis showed a consistency of the results from the overall and subgroup analyses. We also showed that the genetic effect of the rs1801516 polymorphism on acute radiation injuries was

Aircrew radiation exposure: sources-risks-measurement

International Nuclear Information System (INIS)

Duftschmid, K.E.

1994-05-01

A short review is given on the actual aircrew exposure and its sources. The resulting risks for harmful effects to the health and discuss methods for in-flight measurements of exposure is evaluated. An idea for a fairly simple and economic approach to a practical, airborne active dosimeter for the assessment of individual crew exposure is presented. The exposure of civil aircrew to cosmic radiation, should not be considered a tremendous risk to the health, there is no reason for panic. However, being significantly higher than the average exposure to radiation workers, it can certainly not be neglected. As recommended by ICRP, aircrew exposure has to be considered occupational radiation exposure and aircrews are certainly entitled to the same degree of protection, as other ground-based radiation workers have obtained by law, since long time. (author)

Epidemiology and risk assessment for radiation

International Nuclear Information System (INIS)

Badwe, R.A.

2014-01-01

The hazard and exposures from radiation are known with reasonable accuracy. However, at 'low levels' uncertainty persists as to whether the dose response relationship is linear and whether there is a dose threshold, below which there is no risk. Some have proposed that 'low' exposures to radiation may be beneficial, a hypothesis referred to as 'hormesis'. Over recent decades, various expert groups have adopted linear no-threshold dose-response models for radiation and cancer, based on review of epidemiological and biological evidence. The unexpected epidemic of thyroid cancer among children following the Chernobyl disaster was noticed. The research with epidemiological data and knowledge of the radionuclides to which the children were exposed is needed. Currently a debate concerning potential risks of high frequency electromagnetic radiation from mobile phones illustrates another need for further research

Radiation sources, radiation environment and risk level at Dubna

International Nuclear Information System (INIS)

Komochkov, M.M.

1991-01-01

The overall information about ionizing radiation sources, which form radiation environment and risk at Dubna, is introduced. Systematization of the measurement results is performed on the basis of the effective dose and losses of life expectancy. The contribution of different sources to total harm of Dubna inhabitants has been revealed. JINR sources carry in ∼ 4% from the total effective dose of natural and medicine radiation sources; the harm from them is much less than the harm from cigarette smoking. 18 refs.; 2 tabs

Classification system for acute and chronic radiation treatment sequelae

International Nuclear Information System (INIS)

Seegenschmiedt, M.H.; Sauer, R.

1993-01-01

A classification system in German language is proposed for scoring of acute and chronic treatment sequelae after radiotherapy. It includes all important organs and organ systems. The proposed grading corresponds to the four-scale-system of the WHO and UICC. The system is also compatible to the RTOG and EORTC acute and late radiation morbidity scoring criteria. This facilitates the data transfer for retrospective and prospective analysis of monomodal and multimodal radiotherapy treatment regimes. We recommend to use this scoring system in all German speaking countries for multicentric prospective studies. It is possible, that organ-specific sophistications of the toxicity grading will be developed in the future. These additions should conform with (inter)national standards and apply the same four-scale grading of this classification system. (orig.) [de

Radiation risk management at DOE accelerator facilities

International Nuclear Information System (INIS)

Dyck, O.B. van.

1997-01-01

The DOE accelerator contractors have been discussing among themselves and with the Department how to improve radiation safety risk management. This activity-how to assure prevention of unplanned high exposures-is separate from normal exposure management, which historically has been quite successful. The ad-hoc Committee on the Accelerator Safety Order and Guidance [CASOG], formed by the Accelerator Section of the HPS, has proposed a risk- based approach, which will be discussed. Concepts involved are risk quantification and comparison (including with non-radiation risk), passive and active (reacting) protection systems, and probabilistic analysis. Different models of risk management will be presented, and the changing regulatory environment will also be discussed

Potent corticosteroid cream (mometasone furoate) significantly reduces acute radiation dermatitis: results from a double-blind, randomized study

International Nuclear Information System (INIS)

Bostroem, Aasa; Lindman, Henrik; Swartling, Carl; Berne, Berit; Bergh, Jonas

2001-01-01

Purpose: Radiation-induced dermatitis is a very common side effect of radiation therapy, and may necessitate interruption of the therapy. There is a substantial lack of evidence-based treatments for this condition. The aim of this study was to investigate the effect of mometasone furoate cream (MMF) on radiation dermatitis in a prospective, double-blind, randomized study. Material and methods: The study comprised 49 patients with node-negative breast cancer. They were operated on with sector resection and scheduled for postoperative radiotherapy using photons with identical radiation qualities and dosage to the breast parenchyma. The patients were randomized to receive either MMF or emollient cream. The cream was applied on the irradiated skin twice a week from the start of radiotherapy until the 12th fraction (24 Gy) and thereafter once daily until 3 weeks after completion of radiation. Both groups additionally received non-blinded emollient cream daily. The intensity of the acute radiation dermatitis was evaluated on a weekly basis regarding erythema and pigmentation, using a reflectance spectrophotometer together with visual scoring of the skin reactions. Results: MMF in combination with emollient cream treatment significantly decreased acute radiation dermatitis (P=0.0033) compared with emollient cream alone. There was no significant difference in pigmentation between the two groups. Conclusions: Adding MMF, a potent topical corticosteroid, to an emollient cream is statistically significantly more effective than emollient cream alone in reducing acute radiation dermatitis

Association of TGF-β1 and XPD polymorphisms with severe acute radiation-induced esophageal toxicity in locally advanced lung cancer patients treated with radiotherapy

International Nuclear Information System (INIS)

Zhang Li; Yang Ming; Bi Nan; Ji Wei; Wu Chen; Tan Wen; Zhao Lujun; Yu Dianke; Lin Dongxin; Wang Luhua

2010-01-01

Purpose: Radiation-induced esophageal toxicity (RIET) is a dose-limiting toxicity in lung cancer patients receiving radiotherapy. Accumulating evidence indicates that DNA repair and the cytokine pathways play essential roles in radiation-induced diseases. Genetic polymorphisms of genes in these pathways may affect gene function and/or gene expression and lead to different treatment-related esophageal toxicity. Materials and methods: This study investigated the association of 21 polymorphisms in 14 genes, with the occurrence of ≥grade 2 acute RIET. Genotypes were analyzed among 213 stage III lung cancer patients receiving radiotherapy. Results: We used Cox proportional hazard model to examine the effects of genotypes on ≥grade 2 acute RIET risk and Kaplan-Meier estimator to compare effects of different genotypes on such risk. Multivariate analysis showed that CT or TT genotype of TGF-β1-509C/T polymorphism was associated with a significantly higher RIET risk (adjusted hazard ratio [HR] = 2.47; 95% confidence interval (CI) = 1.17-5.24; P = 0.018, or HR = 3.86; 95% CI = 1.50-9.92; P = 0.005), respectively, compared with the CC genotype. Moreover, Lys/Gln+Gln/Gln genotypes of XPD Lys751Gln polymorphism were also associated with a significantly decreased RIET risk (adjusted HR = 0.55; 95% CI = 0.32-0.96; P = 0.030). Conclusions: This report, for the first time, examined the influence of inherited variation in the DNA repair and the cytokine pathways on RIET.

Acute radiation nephritis. Light and electron microscopic observations

International Nuclear Information System (INIS)

Kapur, S.; Chandra, R.; Antonovych, T.

1977-01-01

Light and electron microscopy were used to observe acute radiation nephritis. By light microscopy the changes were of fibrinoid necrosis of the arteries and arterioles with segmental necrosis of the glomerular tufts. By electron microscopy the endocapillary cells reacted by hypertrophy and hyperplasia with increase in cytoplasmic organelles. In addition, disruption of endothelial and epithelial cells from the basement membranes were seen. It is concluded that the electron microscopic changes were unique and may be helpful in differentiating the necrotizing glomerulitis seen in other conditions, especially malignant hypertension

Acute myocardial infarction after mediastinal radiotherapy

International Nuclear Information System (INIS)

Gagliardi, Juan; Tezanos Pinto, Miguel; Avalos, Adolfo; Sarubbi, Augusto; Padilla, Lucio; Espinosa, Daniel

2004-01-01

Mediastinal radiotherapy can affect the heart and great vessels to different degrees. It may turn up as coronary heart disease and less frequently as acute myocardial infarction. We report the case of a patient without coronary risk factors and an antecedent of mediastinal radiotherapy for Hodgkin's lymphoma. Considerations about mediastinal radiation as a risk factor for early development of coronary heart diseases are exposed. (author) [es

Informing people about radiation risks: a review of obstacles to public understanding and effective risk communication

International Nuclear Information System (INIS)

Covello, V.T.

1988-01-01

This paper reviews the literature on informing people about radiation risks. The paper focuses on obstacles to public understanding and effective risk communication. The paper concludes with a set of guidelines for communicating information about radiation risks to the public. The paper also includes an appendix that reviews the literature on one of the most important tools for communicating information about radiation risks: risk comparisons

Radiation risk in Republics Belarus after Chernobyl accident

International Nuclear Information System (INIS)

Saltanova, I.

2006-01-01

Full text: Radiation pollution of the territory of the Republic of Belarus has been considered for a long time as a basic ecological danger source. Since the disaster at Chernobyl, a considerable number of the inhabited areas turned out to be situated on the territory contaminated with the radioactive substances. A risk value of the radiation-inducible affections is used in order to appraise the damage to the health of the population, residing in such regions, in other words - of the long term (stochastic) effects probability, among which malignant neoplasm represents the most serious danger. In many countries the systems of radiological protection and safety criteria are based on ecocentric approaches. Nevertheless the post-Chernobyl situation in the Republic of Belarus is continually producing a wide spectrum of hard questions of human health and social activity on contaminated territories. That is why present work is completely produced in the frameworks of anthropocentric approach. The radiation risk has been evaluated for a number of regions of Gomel areas and Mogilev region in accordance with the linear non-threshold model 'Dose-Effect'. A lifelong risk coefficient of the radiation-inducible cancers of 5% / Zv, offered by the ICRP, is used in the evaluations. The doses, used for the risk assessment, are taken from the Doses Catalogue-1992 of the Ministry of Health, Republic of Belarus, which contains the doses, referring to the years 1991-1992. Correspondingly, our evaluations determine potential cancers, conditioned by the radiation exposure during this period of time. Obtained evaluations do not take into account either the radiation-inducible cancers of the thyroid gland, or the leukemia cases, observed in the liquidators as a result of the radiation exposure in the year 1986. The work also contains an evaluation of the component, specific for the Chernobyl radiation risk, conditioned by the radiation dose, accumulated in the population of the regions

Radiation and risk in physics education

International Nuclear Information System (INIS)

Eijkelhof, H.M.C.

1990-01-01

The study reported in this thesis deals with physics education, particularly with the teaching and learning of radioactivity and ionizing radiation. It is a follow up of earlier research and development work in the Dutch Physics Curriculum Development Project (PLON) on a unit called Ionizing Radiation. The central theme of this unit was the acceptability of the risks of ionizing radiation. Preliminary evaluation of the effectiveness of the PLON-unit showed that pupils appear to have lay-ideas which seem to be resistant to change. In this study the nature and persistence of these lay-ideas have been explored and a set of recommendations have been developed for writing curriculum materials and for teaching strategies, for physics lessons in secondary high school, in order to promote thoughtful risk analysis and assessment as regards applications of ionizing radiation. (H.W.). 225 refs.; 3 figs.; 41 tabs

Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

Science.gov (United States)

Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

2006-01-01

Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

Prototype Biology-Based Radiation Risk Module Project

Science.gov (United States)

Terrier, Douglas; Clayton, Ronald G.; Patel, Zarana; Hu, Shaowen; Huff, Janice

2015-01-01

Biological effects of space radiation and risk mitigation are strategic knowledge gaps for the Evolvable Mars Campaign. The current epidemiology-based NASA Space Cancer Risk (NSCR) model contains large uncertainties (HAT #6.5a) due to lack of information on the radiobiology of galactic cosmic rays (GCR) and lack of human data. The use of experimental models that most accurately replicate the response of human tissues is critical for precision in risk projections. Our proposed study will compare DNA damage, histological, and cell kinetic parameters after irradiation in normal 2D human cells versus 3D tissue models, and it will use a multi-scale computational model (CHASTE) to investigate various biological processes that may contribute to carcinogenesis, including radiation-induced cellular signaling pathways. This cross-disciplinary work, with biological validation of an evolvable mathematical computational model, will help reduce uncertainties within NSCR and aid risk mitigation for radiation-induced carcinogenesis.

Risk analysis of external radiation therapy

International Nuclear Information System (INIS)

Arvidsson, Marcus

2011-09-01

External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

Risk-Adapted Management of Acute Pulmonary Embolism: Recent Evidence, New Guidelines

Directory of Open Access Journals (Sweden)

Anja Käberich

2014-10-01

Full Text Available Venous thromboembolism (VTE, the third most frequent acute cardiovascular syndrome, may cause life-threatening complications and imposes a substantial socio-economic burden. During the past years, several landmark trials paved the way towards novel strategies in acute and long-term management of patients with acute pulmonary embolism (PE. Risk stratification is increasingly recognized as a cornerstone for an adequate diagnostic and therapeutic management of the highly heterogeneous population of patients with acute PE. Recently published European Guidelines emphasize the importance of clinical prediction rules in combination with imaging procedures (assessment of right ventricular function and laboratory biomarkers (indicative of myocardial stress or injury for identification of normotensive PE patients at intermediate risk for an adverse short-term outcome. In this patient group, systemic full-dose thrombolysis was associated with a significantly increased risk of intracranial bleeding, a complication which discourages its clinical application unless hemodynamic decompensation occurs. A large-scale clinical trial program evaluating new oral anticoagulants in the initial and long-term treatment of venous thromboembolism showed at least comparable efficacy and presumably increased safety of these drugs compared to the current standard treatment. Research is continuing on catheter-directed, ultrasound-assisted, local, low-dose thrombolysis in the management of intermediate-risk PE.

Risk Factors for Acute Kidney Injury in Severe Rhabdomyolysis

Science.gov (United States)

Rodríguez, Eva; Soler, María J.; Rap, Oana; Barrios, Clara; Orfila, María A.; Pascual, Julio

2013-01-01

Background Acute kidney injury (AKI) is a life-threatening complication of severe rhabdomyolysis. This study was conducted to assess risk factors for AKI and to develop a risk score for early prediction. Methods Retrospective observational cohort study with a 9-year follow-up, carried out in an acute-care teaching-affiliated hospital. A total of 126 patients with severe rhabdomyolysis defined as serum creatine kinase (CK) > 5,000 IU/L fulfilled the inclusion criteria. Univariate and logistic regression analyses were performed to determine risk factors for AKI. Based on the values obtained for each variable, a risk score and prognostic probabilities were estimated to establish the risk for developing AKI. Results The incidence of AKI was 58%. Death during hospitalization was significantly higher among patients with AKI, compared to patients without AKI (19.2% vs 3.6%, p = 0.008). The following variables were independently associated with AKI: peak CK (odds ratio [OR] 4.9, 95%CI 1.4-16.8), hypoalbuminemia (rhabdomyolysis may be useful in clinical practice, particularly to implement early preventive measures. PMID:24367578

Medical management of severe local radiation injury after acute X-ray exposure

International Nuclear Information System (INIS)

Bushmanov, A.; Nadezhina, N.; Kretov, A.

2008-01-01

Medical management during acute period in a case of severe local radiation injury after acute X-ray exposure includes 3 stages. During the fist stage patient got conservative treatment according to the common pathogenetic mechanisms of LRI (dis aggregating therapy, stimulation of regeneration, dis intoxication therapy, antibiotic therapy, pain relief therapy, Local anti-burn therapy-specific non-adhesive bandage with antiseptic and anti-burn medicaments); estimation of severity, deepness and area of injury by clinical picture and dates of instrumental methods of examining; defining necessity and volume of surgical treatment; preparing arrangements for surgical treatment. This stage ends with forming of demarcation line of a very hard severity of a Local Radiation Injure. The second stage includes necrectomy of the area of a very hard severity with microsurgical plastic by re vascularized flap and auto dermoplastic. The third stage - adaptation of re vascularized flap and total epithelization of injured area. (author)

Risks and hazards from conventional and radiation sources

International Nuclear Information System (INIS)

Iyer, P.S.; Ganguly, A.K.

1978-01-01

Beneficial uses of radioisotopes in medicine, industry, agriculture and research are discussed. In absence of adequate safety precautions, uses of radiation may also result in harmful biological effects or genetic effects. Radiation risks and hazards are evaluated by comparing with other risks and hazards which are routinely encountered. The risk of fatality per year by various causes in U.S.A. is given. It is stated with examples and observations that some of the routine habits and necessities and minor luxuries are more risky than radiation risks. Countrywide radiation safety program in India by the Department of Atomic Energy is described in brief. Data are given to show that the risks from radiation are much lower in comparison with many conventional sources. More efficient equipment such as image intensifier is recommended to help to reduce the patient dose. It is stated that caution has to be exercised while handling the X-ray machines which may be harmful not only to patients but to doctors also. As regards, nuclear medicine, it is mentioned that though it is a fast expanding speciality in India, the number of procedures carried out in various centres is small as compared to U.S.A. and France. Some instances are given to show the consequences of the ignorance of the radiation hazards in operating machines in X-ray and gamma ray beam therapy facilities. A survey made by DRP, BARC revealed that some research laboratories lacked basic radiation protection requirements in using X-ray crystallography or analytical equipment. (B.G.W.)

The importance of radiation risk assessment

International Nuclear Information System (INIS)

Pochin, E.E.

1979-01-01

In its Publication 26, ICRP recommends a system of radiation dose limitation that is designed to ensure adequate protection from the harmful effects of radiation in conditions both of occupational and of environmental exposure. Clearly, however, no such system can be recommended or accepted as sufficiently safe unless the risks of the resultant exposures have been quantitatively assessed. Publication 26 reflects the increasing quantitative information that is now available on (a) carcinogenic risks of radiation in man, both from exposure of the whole body and from that of individual organs, at moderate exposures; (b) theoretical bases for inference of risk, from moderate to lower exposures; (c) genetic risks in the mouse, and inferences from such risks to those in man; (d) the dose equivalent levels at which certain non-stochastic effects may be induced. Despite a number of uncertainties, substantially improved estimates can therefore be made of the levels of safety that are likely to be achieved by observing the Commission's recommended dose limits, and the associated system of limitation of exposures to levels as low as reasonably achievable below these limits. Both for occupational exposure and for the exposure of the members of the public, these estimates are expressed in Publication 26 in terms of the risk of inducing fatal malignancies or serious hereditary ill health. These frequencies are compared with those of occupational fatalities in other industries or with accidental fatalities amongst the general public. The comparison between harm from radiation and from other agents in different industries is extended in ICRP-27 (on ''Problems Involved in Developing an Index of Harm'') in a review of the time lost through occupational diseases and non-fatal accidents, as well as from fatal diseases and accidents, so that the levels of safety achievable by the Commission's recommendations can be reviewed in the general perspective of occupational safety. (author)

Therapy and prophylaxis of acute and late radiation-induced sequelae of the esophagus

International Nuclear Information System (INIS)

Zimmermann, F.B.; Geinitz, H.; Feldmann, H.J.

1998-01-01

Background: Radiation-induced esophagitis is a frequent acute side effect in curative and palliative radiotherapy of thoracal and cervical tumors. Late reactions are rare but might be severe. Methods: A resarch for reports on prophylactic and supportive therapies of radiation-induced esophagitis was performed (Medline, Cancerlit, and others). Results: Nutrition must be ensured and symptomatic relief of sequelae is important, especially in the case of dysphagia. The latter can be improved by topic or systemic analgetics. If esophageal spasm occurs, calcium antagonists might help. In case of gastro-esophageal reflux proton pump inhibitors should be used. There is no effective prophylactic measure for radiation esophagitis. Late side effects with clinical relevance are rare in conventional radiotherapy. Chronic ulcera, fistula or stenosis may develop. Before any treatment, a tumor infiltration of the esophagus should be excluded by biopsy. This can lead more often to late complications than radiation therapy itself. Nutrition should be ensured by endoscopic dilation, stent-implantation, or endoscopic percutaneous gastrostomy. Local injection of steroids might be used to avoid an early restenosis. Conclusions: An intensive symptomatic therapy of acute esophagitis is reasonable. Effective prophylaxis do not exist. Late radiation induced sequelae is rare. Therefore, a tumor recurrence should be excluded in cases of dysphagia. Securing nutrition by PEG, stent, or port is well in the fore. (orig.) [de

Risk and benefits in ionizing radiation uses

International Nuclear Information System (INIS)

2010-08-01

This meeting include: A tribute to Szeinfeld, presentation software for population dose, impact on radiation protection, radiation protection hospital and population exposed workers, regulation and licensing. radiological emergencies, risk, inspection, external radiotherapy and radiation protection with photons, brachytherapy, industrial, environmental monitoring, food irradiation, nuclear power, nuclear medicine.

Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

International Nuclear Information System (INIS)

Bouffler, S.D.; Breckon, G.; Cox, R.

1996-01-01

Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author)

Risk of cataract in the context of acute and chronic exposure

Directory of Open Access Journals (Sweden)

Tukov A.R.

2016-12-01

Full Text Available Purpose: estimation of the risk of cataract using doses of different types of radiation. Material and methods. The study is carried out using the information database of the NP, recovery workers of the accident at the Chernobyl NP. Professional exposure and dose received during 30 km zone were used to calculate the risk. Results. The study shows the use of one of their parts of the total radiation dose of man, leads to obtaining of different levels of the risk of disease. Conclusion. Only use of a total radiation dose can lead to obtaining of the correct results of evaluating the risk of the emergence of the radiation- induced diseases.

Implications of radiation risk for practical dosimetry

International Nuclear Information System (INIS)

Dennis, J.A.

1984-01-01

Radiobiological experiments with animals and cells have led to an expectation that the risks of cancer and hereditary effects are reduced at low doses and low dose rates of low LET radiation. Risk estimates derived from human exposures at high doses and dose rates usually contain an allowance for low dose effects in comparison with high dose effects, but no allowance may have been made for low dose rate effects. Although there are reasons for thinking that leukaemia risks may possibly have been underestimated, the total cancer risk assumed by ICRP for occupational exposures is reasonably realistic. For practical dosimetry the primary dose concepts and limits have to be translated into secondary quantities that are capable of practical realisation and measurement, and which will provide a stable and robust system of metrology. If the ICRP risk assumptions are approximately correct, it is extremely unlikely that epidemiological studies of occupational exposures will detect the influence of radiation. Elaboration of dosimetry and dose recording for epidemiological purposes is therefore unjustified except possibly in relation to differences between high and low LET radiations. (author)

Primary Sjogren's syndrome and the risk of acute pancreatitis: a nationwide cohort study.

Science.gov (United States)

Chang, Chi-Ching; Chang, Yu-Sheng; Wang, Shu-Hung; Lin, Shyr-Yi; Chen, Yi-Hsuan; Chen, Jin Hua

2017-08-11

Studies on the risk of acute pancreatitis in patients with primary Sjogren's syndrome (pSS) are limited. We evaluated the effects of pSS on the risk of acute pancreatitis in a nationwide, population-based cohort in Taiwan. Population-based retrospective cohort study. We studied the claims data of the >97% Taiwan population from 2002 to 2012. We identified 9468 patients with pSS by using the catastrophic illness registry of the National Health Insurance Database in Taiwan. We also selected 37 872 controls that were randomly frequency matched by age (in 5 year bands), sex and index year from the general population. We analysed the risk of acute pancreatitis by using Cox proportional hazards regression models including sex, age and comorbidities. From 23.74 million people in the cohort, 9468 patients with pSS (87% women, mean age=55.6 years) and 37 872 controls were followed-up for 4.64 and 4.74 years, respectively. A total of 44 cases of acute pancreatitis were identified in the pSS cohort versus 105 cases in the non-pSS cohort. Multivariate Cox regression analysis indicated that the incidence rate of acute pancreatitis was significantly higher in the pSS cohort than in the non-pSS cohort (adjusted HR (aHR) 1.48, 95% CI 1.03 to 2.12). Cyclophosphamide use increased the risk of acute pancreatitis (aHR 5.27, 95% CI 1.16 to 23.86). By contrast, hydroxychloroquine reduced the risk of acute pancreatitis (aHR 0.23, 95% CI 0.09 to 0.55). This nationwide, retrospective cohort study demonstrated that the risk of acute pancreatitis was significantly higher in patients with pSS than in the general population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Radiation quality and radiation risks - some current problems

International Nuclear Information System (INIS)

Kellerer, A.M.; Hahn, K.

1989-01-01

The newly evaluated cancer mortality data of the atomic bomb survivors suggest substantially enhanced risk estimates, and the various factors that are involved in the change are considered. The enhanced risk estimates have already led to added restrictions in the dose limits for radiation workers, and there may be a further tightening of regulations in the future. The impending revision of the quality factors in radiation protection may, therefore, lead to practical difficulties, and a careful consideration of the various aspects involved in a revision is required. A liaison group of ICRU and ICRP has proposed a reformulation of the quality factor that is related not to the LET, but to the microdosimetric variably y. The relation leads to increased quality factors for neutrons, but also to a quality factor for γ rays of only 0.5. Alternatives are presented that relate the quality factor to LET and that retain γ- rays as the reference radiation. One option corresponds to different quality factors for γ rays and X-rays, the other option sets the quality factor for photons approximately equal to unity, irrespective of energy. (author)

[Use of ionizing radiation sources in metallurgy: risk assessment].

Science.gov (United States)

Giugni, U

2012-01-01

Use of ionizing radiation sources in the metallurgical industry: risk assessment. Radioactive sources and fixed or mobile X-ray equipment are used for both process and quality control. The use of ionizing radiation sources requires careful risk assessment. The text lists the characteristics of the sources and the legal requirements, and contains a description of the documentation required and the methods used for risk assessment. It describes how to estimate the doses to operators and the relevant classification criteria used for the purpose of radiation protection. Training programs must be organized in close collaboration between the radiation protection expert and the occupational physician.

Knowledge of medical imaging radiation dose and risk among doctors

International Nuclear Information System (INIS)

Brown, Nicholas; Jones, Lee

2013-01-01

The growth of computed tomography (CT) and nuclear medicine (NM) scans has revolutionised healthcare but also greatly increased population radiation doses. Overuse of diagnostic radiation is becoming a feature of medical practice, leading to possible unnecessary radiation exposures and lifetime-risks of developing cancer. Doctors across all medical specialties and experience levels were surveyed to determine their knowledge of radiation doses and potential risks associated with some diagnostic imaging. A survey relating to knowledge and understanding of medical imaging radiation was distributed to doctors at 14 major Queensland public hospitals, as well as fellows and trainees in radiology, emergency medicine and general practice. From 608 valid responses, only 17.3% correctly estimated the radiation dose from CT scans and almost 1 in 10 incorrectly believed that CT radiation is not associated with any increased lifetime risk of developing cancer. There is a strong inverse relationship between a clinician's experience and their knowledge of CT radiation dose and risks, even among radiologists. More than a third (35.7%) of doctors incorrectly believed that typical NM imaging either does not use ionising radiation or emits doses equal to or less than a standard chest radiograph. Knowledge of CT and NM radiation doses is poor across all specialties, and there is a significant inverse relationship between experience and awareness of CT dose and risk. Despite having a poor understanding of these concepts, most doctors claim to consider them prior to requesting scans and when discussing potential risks with patients.

Ionizing radiation, genetic risks and radiation protection

International Nuclear Information System (INIS)

Sankaranarayanan, K.

1992-01-01

With one method of risk estimation, designed as the doubling dose method, the estimates of total genetic risk (i.e., over all generation) for a population continuously exposed at a rate of 0.01 Gy/generation of low LET irradiation are about 120 cases of Mendelian and chromosomal diseases/10 6 live births and about the same number of cases for multifactorial diseases (i.e., a total of 240 cases/10 6 ). These estimates provide the basis for risk coefficients for genetic effects estimated by ICRP (1991) in its Publication 60. These are: 1.0%/Sv for the general population (which is 40% of 240/10 6 /0.01 Gy), and 0.6%/Sv for radiation workers (which is 60% of that for the general population). The results of genetic studies carried out on the Japanese survivors of A-bombs have shown no significant adverse effects attributable to parental radiation exposures. The studies of Gardner and colleagues suggest that the risk of leukaemia in children born to male workers in the nuclear reprocessing facility in Sellafield, U.K., may be increased. However, this finding is at variance with the results from the Japanese studies and at present, does not lend itself to a simple interpretation based on radiobiological principles. In the light of recent advances in the molecular biology of naturally-occurring human Mendelian diseases and what we presently know about multifactorial diseases, arguments are advanced to support the thesis that (i) current risk estimates for Mendelian diseases may be conservative and (ii) an overall doubling dose for all adverse genetic effects may be higher than the 1 Gy currently used (i.e., the relative risks are probably lower). (author)

Normal tissue tolerance to external beam radiation therapy: Skin

International Nuclear Information System (INIS)

Ginot, A.; Doyen, J.; Hannoun-Levi, J.M.; Courdi, A.

2010-01-01

Acute skin toxicity is frequent during radiation therapy and can lead to temporary arrest of the treatment. Chronic toxicity can occur and conduct to cosmetic problems. Alopecia is the most frequent toxicity concerning hair and is most of the time reversible. Several factors linked to patients influence skin toxicity, such as under-nutrition, old age, obesity, smoking, skin diseases, autoimmune diseases, failure of DNA reparation. Skin, hair and nail toxicities depend also on radiation schedule. Acute toxicity is greater when dose per fraction increases. Chronic and acute toxicities are more often when total dose increases. Under 45 Gy, the risk of severe skin toxicity is low, and begins above 50 Gy. Skin toxicity depends also on the duration of radiotherapy and split course schedules are associated with less toxicities. Irradiation surface seems to influence skin toxicity but interaction is more complex. Reirradiation is often feasible in case of cancer recurrence but with a risk of grade 3-4 toxicity above all in head and neck cancer. The benefit/risk ratio has to be always precisely evaluated. Permanent alopecia is correlated with the follicle dose. Modern techniques of radiation therapy allow to spare skin. (authors)

Combined Hydration and Antibiotics with Lisinopril to Mitigate Acute and Delayed High-dose Radiation Injuries to Multiple Organs.

Science.gov (United States)

Fish, Brian L; Gao, Feng; Narayanan, Jayashree; Bergom, Carmen; Jacobs, Elizabeth R; Cohen, Eric P; Moulder, John E; Orschell, Christie M; Medhora, Meetha

2016-11-01

The NIAID Radiation and Nuclear Countermeasures Program is developing medical agents to mitigate the acute and delayed effects of radiation that may occur from a radionuclear attack or accident. To date, most such medical countermeasures have been developed for single organ injuries. Angiotensin converting enzyme (ACE) inhibitors have been used to mitigate radiation-induced lung, skin, brain, and renal injuries in rats. ACE inhibitors have also been reported to decrease normal tissue complication in radiation oncology patients. In the current study, the authors have developed a rat partial-body irradiation (leg-out PBI) model with minimal bone marrow sparing (one leg shielded) that results in acute and late injuries to multiple organs. In this model, the ACE inhibitor lisinopril (at ~24 mg m d started orally in the drinking water at 7 d after irradiation and continued to ≥150 d) mitigated late effects in the lungs and kidneys after 12.5-Gy leg-out PBI. Also in this model, a short course of saline hydration and antibiotics mitigated acute radiation syndrome following doses as high as 13 Gy. Combining this supportive care with the lisinopril regimen mitigated overall morbidity for up to 150 d after 13-Gy leg-out PBI. Furthermore, lisinopril was an effective mitigator in the presence of the growth factor G-CSF (100 μg kg d from days 1-14), which is FDA-approved for use in a radionuclear event. In summary, by combining lisinopril (FDA-approved for other indications) with hydration and antibiotics, acute and delayed radiation injuries in multiple organs were mitigated.

Epidemiological studies in high background radiation areas

International Nuclear Information System (INIS)

Akiba, Suminori

2012-01-01

Below the doses of 100-200 mSv of radiation exposure, no acute health effect is observed, and the late health effects such as cancer are yet unclear. The problems making the risk evaluation of low dose radiation exposure difficult are the fact that the magnitude of expected health effects are small even if the risk is assumed to increase in proportion to radiation doses. As a result, studies need to be large particular when dealing with rare disease such as cancer. In addition, the expected health effects are so small that they can easily be masked by lifestyles and environmental factors including smoking. This paper will discuss cancer risk possibly associated with low-dose and low-dose rate radiation exposure, describing epidemiological studies on the residents in the high-background radiation areas. (author)

Functional Measures for Fall Risk in the Acute Care Setting: A Review.

Science.gov (United States)

Bassett, Alaina M; Siu, Ka-Chun; Honaker, Julie A

2017-04-01

This review explores the evidence pertaining to the use of functional ability measures for fall risk in the acute care setting. We included studies from six bibliographic databases that investigated fall risk functional ability measures in hospitalized older adults (≥55 years). We utilized the following search terms: acute care, subacute care, critical care, inpatient, fall, and fall prevention. Nineteen articles met the inclusion criteria. Timed "Up and Go" (TUG) was identified as a feasible fall risk functional ability measure for clinicians; it demonstrated clinical performance of fair sensitivity (56%-68%) and good specificity (74%-80%). Clinical performance of other measures (Berg Balance Scale and Functional Reach test) was not as favorable as the TUG. Functional ability measures are underutilized in the acute care setting, potentially due to limited knowledge and training on administration. Combining functional measures with subjective screening tools may optimize performance and accuracy of identifying fall risk identification.

Low-dose extrapolation of radiation health risks: some implications of uncertainty for radiation protection at low doses.

Science.gov (United States)

Land, Charles E

2009-11-01

Ionizing radiation is a known and well-quantified human cancer risk factor, based on a remarkably consistent body of information from epidemiological studies of exposed populations. Typical examples of risk estimation include use of Japanese atomic bomb survivor data to estimate future risk from radiation-related cancer among American patients receiving multiple computed tomography scans, persons affected by radioactive fallout, or persons whose livelihoods involve some radiation exposure, such as x-ray technicians, interventional radiologists, or shipyard workers. Our estimates of radiation-related risk are uncertain, reflecting statistical variation and our imperfect understanding of crucial assumptions that must be made if we are to apply existing epidemiological data to particular situations. Fortunately, that uncertainty is also highly quantifiable, and can be presented concisely and transparently. Radiation protection is ultimately a political process that involves consent by stakeholders, a diverse group that includes people who might be expected to be risk-averse and concerned with plausible upper limits on risk (how bad could it be?), cost-averse and concerned with lower limits on risk (can you prove there is a nontrivial risk at current dose levels?), or combining both points of view. How radiation-related risk is viewed by individuals and population subgroups also depends very much on perception of related benefit, which might be (for example) medical, economic, altruistic, or nonexistent. The following presentation follows the lead of National Council on Radiation Protection and Measurements (NCRP) Commentary 14, NCRP Report 126, and later documents in treating radiation protection from the viewpoint of quantitative uncertainty analysis.

Representing and Retrieving Patients' Falls Risk Factors and Risk for Falls among Adults in Acute Care through the Electronic Health Record

Science.gov (United States)

Pfaff, Jann

2013-01-01

Defining fall risk factors and predicting fall risk status among patients in acute care has been a topic of research for decades. With increasing pressure on hospitals to provide quality care and prevent hospital-acquired conditions, the search for effective fall prevention interventions continues. Hundreds of risk factors for falls in acute care…

Perioperative aspirin and clonidine and risk of acute kidney injury

DEFF Research Database (Denmark)

Garg, Amit X; Kurz, Andrea; Sessler, Daniel I

2014-01-01

IMPORTANCE: Acute kidney injury, a common complication of surgery, is associated with poor outcomes and high health care costs. Some studies suggest aspirin or clonidine administered during the perioperative period reduces the risk of acute kidney injury; however, these effects are uncertain...... and each intervention has the potential for harm. OBJECTIVE: To determine whether aspirin compared with placebo, and clonidine compared with placebo, alters the risk of perioperative acute kidney injury. DESIGN, SETTING, AND PARTICIPANTS: A 2 × 2 factorial randomized, blinded, clinical trial of 6905...... patients undergoing noncardiac surgery from 88 centers in 22 countries with consecutive patients enrolled between January 2011 and December 2013. INTERVENTIONS: Patients were assigned to take aspirin (200 mg) or placebo 2 to 4 hours before surgery and then aspirin (100 mg) or placebo daily up to 30 days...

In vitro radiosensitivity of primary human fibroblasts. Lack of correlation with acute radiation toxicity in patients with head and neck cancer

International Nuclear Information System (INIS)

Rudat, Volker; Dietz, Andreas; Conradt, Christian; Weber, Klaus-Josef; Flentje, Michael

1997-01-01

Background and purpose: There is a considerable hope among clinicians and radiobiologists to detect genetically radiosensitive patients prior to radiotherapy. A predictive assay would enable adjustment of the total irradiation dose to the individual at a constant risk of normal tissue complications. In this prospective study, the clonogenic survival assay for primary human fibroblasts to determine radiosensitivity in vitro was evaluated and then correlated with clinically observed acute radiation reactions. Materials and methods: One hundred twenty-five independent survival experiments with primary fibroblasts derived from 63 biopsies from 55 cancer and non-cancer patients were performed. Results: A wide variation of cell survival between biopsies was detected. Statistical analysis revealed a highly significantly larger interindividual than intraindividual variation of SF2 values. However, a considerable scatter of SF2 values in repeated experiments was observed in individual cases. Age, gender, disease status (cancer patient, non-cancer patient) and origin of fibroblasts (skin, periodontal tissue) were demonstrated not to be statistically significant confounding factors on the intrinsic radiosensitivity in vitro. In a prospective study, no correlation of the SF2 and acute reactions in 25 patients with head and neck cancer treated with a primary accelerated radiochemotherapy was detected. Conclusion: Our data show that the clonogenic assay is able to distinguish between intrinsic radiosensitivities of primary human fibroblasts if a statistical approach is used but does not predict acute radiation toxicity

Radiation induced cancer risk, detriment and radiation protection

International Nuclear Information System (INIS)

Sinclair, W.K.

1992-01-01

Recommendations on radiation protection limits for workers and for the public depend mainly on the total health detriment estimated to be the result of low dose ionizing radiation exposure. This detriment includes the probability of a fatal cancer, an allowance for the morbidity due to non-fatal cancer and the probability of severe hereditary effects in succeeding generations. In a population of all ages, special effects on the fetus particularly the risk of mental retardation at defined gestational ages, should also be included. Among these components of detriment after low doses, the risk of fatal cancer is the largest and most important. The estimates of fatal cancer risk used by ICRP in the 1990 recommendations were derived almost exclusively from the study of the Japanese survivors of the atomic bombs of 1945. How good are these estimates? Uncertainties associated with them, apart from those due to limitations in epidemiological observation and dosimetry, are principally those due to projection forward in time and extrapolation from high dose and dose rate to low dose and dose rate, each of which could after the estimate by a factor of 2 or so. Recent estimates of risk of cancer derived directly from low dose studies are specific only within very broad ranges of risk. Nevertheless, such studies are important as confirmation or otherwise of the estimates derived from the atomic bomb survivors. Recent U.S. British and Russian studies are examined in this light. (author)

Chronic and acute risk assessment of human exposed to novaluron-bifenthrin mixture in cabbage.

Science.gov (United States)

Shi, Kaiwei; Li, Li; Li, Wei; Yuan, Longfei; Liu, Fengmao

2016-09-01

Based on the dissipation and residual level in cabbage determined by gas chromatography coupled with an electron capture detector (GC-ECD), chronic and acute risk assessments of the novaluron and bifenthrin were investigated. At different spiked levels, mean recoveries were between 81 and 108 % with relative standard deviations (RSDs) from 1.1 to 6.8 %. The limit of quantification (LOQ) was 0.01 mg kg(-1), and good linearity with correlation coefficient (>0.9997) were obtained. The half-lives of novaluron and bifenthrin in cabbage were in the range of 3.2~10 days. Based on the consumption data in China, the risk quotients (RQs) of novaluron and bifenthrin were all below 100 %. The chronic and acute risk of novaluron in cabbage was relatively low, while bifenthrin exerts higher acute risk to humans than chronic risk. The obtained results indicated that the use of novaluron-bifenthrin mixture does not seem to pose any chronic or acute risk to humans even if cabbages are consumed at high application dosages and short preharvest interval (PHI).

Knowledge of medical imaging radiation dose and risk among doctors.

Science.gov (United States)

Brown, Nicholas; Jones, Lee

2013-02-01

The growth of computed tomography (CT) and nuclear medicine (NM) scans has revolutionised healthcare but also greatly increased population radiation doses. Overuse of diagnostic radiation is becoming a feature of medical practice, leading to possible unnecessary radiation exposures and lifetime-risks of developing cancer. Doctors across all medical specialties and experience levels were surveyed to determine their knowledge of radiation doses and potential risks associated with some diagnostic imaging. A survey relating to knowledge and understanding of medical imaging radiation was distributed to doctors at 14 major Queensland public hospitals, as well as fellows and trainees in radiology, emergency medicine and general practice. From 608 valid responses, only 17.3% correctly estimated the radiation dose from CT scans and almost 1 in 10 incorrectly believed that CT radiation is not associated with any increased lifetime risk of developing cancer. There is a strong inverse relationship between a clinician's experience and their knowledge of CT radiation dose and risks, even among radiologists. More than a third (35.7%) of doctors incorrectly believed that typical NM imaging either does not use ionising radiation or emits doses equal to or less than a standard chest radiograph. Knowledge of CT and NM radiation doses is poor across all specialties, and there is a significant inverse relationship between experience and awareness of CT dose and risk. Despite having a poor understanding of these concepts, most doctors claim to consider them prior to requesting scans and when discussing potential risks with patients. © 2012 The Authors. Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists.

Review of the current status of radiation risk estimates

International Nuclear Information System (INIS)

Charles, M.W.; Little, M.P.

1988-10-01

This report reviews the current status of radiation risk estimation for low linear energy transfer radiation. Recent statements by various national and international organisations regarding risk estimates are critically discussed. The recently published revised population risk estimates from the study of Japanese bomb survivors are also reviewed and used with some unpublished data from Japan to calculate risk figures for a general work force. (author)

Use of methimazole and risk of acute pancreatitis: A case-control study in Taiwan.

Science.gov (United States)

Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu

2016-01-01

Some cases of acute pancreatitis have been reported to be associated with use of methimazole. The aim of this study was to investigate the relationship between use of methimazole and risk of acute pancreatitis on the basis of a systematic analysis. This was a population-based case-control study analyzing the database of the Taiwan National Health Insurance Program. There were 5764 individuals aged 20-84 years with a first attack of acute pancreatitis from 1998 to 2011 as the cases and 23,056 randomly selected sex- and age-matched individuals without acute pancreatitis as the controls. Use of methimazole was categorized as "never use" and "ever use." We estimated the relative risk of acute pancreatitis associated with the use of methimazole by calculating the odds ratio (OR) with 95% confidence interval (CI) using a multivariable logistic regression model. After adjustment for confounding factors, the OR of acute pancreatitis was 0.91 in individuals with ever use of methimazole, when compared with individuals with never use of methimazole (95% CI, 0.60-1.38). Unlike methimazole use, alcohol-related disease, biliary stone, cardiovascular disease, chronic obstructive pulmonary disease, diabetes mellitus, hepatitis B, hepatitis C, and hypertriglyceridemia were factors significantly associated with acute pancreatitis. Our study does not detect a substantial association between the use of methimazole and risk of acute pancreatitis on the basis of systematic analysis. There appears to be a discrepancy between case reports and our systematic analysis about the association between the use of methimazole and risk of acute pancreatitis.

The modes of death in mammals exposed to whole body radiation (acute radiation syndromes)

International Nuclear Information System (INIS)

Santos, O.R. dos.

1990-07-01

When an animal is exposed to a sufficient amount of radiation, there will be changes in many organs of the body, and as a result of either the effects in one particular organ or the interaction of effects in several organs, the animal as a whole will show characteristic syndromes. Some syndromes result inevitably in death. Others may or may not be lethal, depending on the extent of the tissue damage. The time of appearance of the syndromes, their duration, and the survival of the organism depend on many factors. Whole body acute doses of radiation produce the same spectrum of Central Nervous System (CNS), Gastrointestinal (GI) and Bone Marrow (BM) injury in man as was described for animals. Damage to the skin, ovary and testis are an integral and important part of the symptoms. (author) [pt

Emerging Radiation Health-Risk Mitigation Technologies

International Nuclear Information System (INIS)

Wilson, J.W.; Cucinotta, F.A.; Schimmerling, W.

2004-01-01

Past space missions beyond the confines of the Earth's protective magnetic field have been of short duration and protection from the effects of solar particle events was of primary concern. The extension of operational infrastructure beyond low-Earth orbit to enable routine access to more interesting regions of space will require protection from the hazards of the accumulated exposures of Galactic Cosmic Rays (GCR). There are significant challenges in providing protection from the long-duration exposure to GCR: the human risks to the exposures are highly uncertain and safety requirements places unreasonable demands in supplying sufficient shielding materials in the design. A vigorous approach to future radiation health-risk mitigation requires a triage of techniques (using biological and technical factors) and reduction of the uncertainty in radiation risk models. The present paper discusses the triage of factors for risk mitigation with associated materials issues and engineering design methods

Effect of BMPs on hematopoietic injury of acute radiation sickness in mice

International Nuclear Information System (INIS)

Tian Qiong; Zhang Shaozhang; Pu Qin; Zhang Fake; Hannah, X.H.

2000-01-01

The purpose of this paper is to investigate the effect of Bone morphogenetic proteins (BMPs) on hematopoietic acute radiation sickness in mice. BMP, rhBMP-2m and PBK/hBMP-2-NIH3T3 cells were obtained separately by chemistry, molecule biological method and genetherapy method. In this study, the effect of BMPs on hematopoiesis was detected at postirradiation: some hematological parameters, 30 days the survival ratio and formation of bone marrow CFU-GM colony. The experiments indicate that when phBMP (purified bovine bone morphogenetic protein) can increase the formation of bone narrow CFU-GM colony (p<0.05) at 10th d after irradiation. Irradiation control group's mice died in 30 days, but effect of rhBMP-2m on the survival of mice after 7.5Gy irradiation, was detected whereas there were 10%, 15% and 35% all mice of survived after injection i.p. with 0.5 mg, 1.0 mg and 2.0 mg of rhBMP-2m respectively. All hematological parameters of treated mice were significantly higher than control group (p<0.01). PBK/hBMP-2-NIH3T3 cells were established and transplanted into mice irradiated by 7.0Gy r ray by i.p., the survival ratio of treated mice higher than negative control group (p<0.01), and all hematopoietic parameters were increased statistically significant (p<0.01). These data support the our hypothesis: BMPs can treat the acute radiation sickness. The results indicate that in adult mice, BMPs can recover or treat the hematopoietic injury of acute radiation sickness in mice. (author)

Radiation risk assessment of reprocessed uranium

International Nuclear Information System (INIS)

Cardenas, Hugo R.; Perez, Aldo E.; Luna, Manuel F.; Becerra, Fabian A.

1999-01-01

Reprocessed uranium contains 232 U, which is not found in nature, as well as 234 U which is present in higher proportion than in natural uranium. Both isotopes modify the radiological properties of the material. The paper evaluates the increase of the internal and external radiation risk on the base of experimental data and theoretical calculations. It also suggests measures to be taken in the production of fuel elements with slightly enriched uranium.The radiation risk of reprocessed uranium is directly proportional to the content of 232 U and 234 U as well as to the aging time of the material

Radiation Risk Associated with Low Doses of Ionizing Radiation: Irrational Fear or Real Danger

International Nuclear Information System (INIS)

Reshetin, V.

2007-01-01

The established worldwide practice of protecting people from radiation based on the assessments of radiation risk received in the researches carried out earlier costs hundreds of billions of dollars a year to implement. In the opinion of the well-known experts, the maintenance of the existing radiation protection regulations or moreover acceptance of more tough regulations can influence the development of nuclear power engineering. The accepted practice of assessment of human health risk from radiation may also significantly affect our perception of threats of radiation terrorism. In this work, the critical analysis of publications on the assessment of the effects of small doses of radiation on human health is carried out. In our analysis, we especially emphasize the data on cancer mortality among survivors of the atomic bombing of Hiroshima and Nagasaki who received instantaneous radiation doses of less than 200 mSv including the data on leukemia and solid cancer, as well as epidemiological studies in the regions of India and China with high level of natural radiation. Since the investigations of radiation risk is a base for formulating modern radiation protection regulations, their reliability and validity are of great importance. As follows from the analysis, the subsequent, during three decades, toughening of radiation protection regulations has already led to exceedingly prohibitive standards and impractical recommendations the science-based validity of which can cause serious doubts. Now, a number of world-wide known scientists and authoritative international organizations call for revision of these standards and of the radiation safety concept itself. (author)

2015 Space Radiation Standing Review Panel

Science.gov (United States)

Steinberg, Susan

2015-01-01

The 2015 Space Radiation Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on December 8 - 9, 2015. The SRP met with representatives from the Space Radiation Element and members of the Human Research Program (HRP) to review the updated research plan for the Risk of Radiation Carcinogenesis Cancer Risk. The SRP also reviewed the newly revised Evidence Reports for the Risk of Acute Radiation Syndromes Due to Solar Particle Events (SPEs) (Acute Risk), the Risk of Acute (In-flight) and Late Central Nervous System Effects from Radiation Exposure (CNS Risk), and the Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation (Degen Risk), as well as a status update on these Risks. The SRP would like to commend Dr. Simonsen, Dr. Huff, Dr. Nelson, and Dr. Patel for their detailed presentations. The Space Radiation Element did a great job presenting a very large volume of material. The SRP considers it to be a strong program that is well-organized, well-coordinated and generates valuable data. The SRP commended the tissue sharing protocols, working groups, systems biology analysis, and standardization of models. In several of the discussed areas the SRP suggested improvements of the research plans in the future. These include the following: It is important that the team has expanded efforts examining immunology and inflammation as important components of the space radiation biological response. This is an overarching and important focus that is likely to apply to all aspects of the program including acute, CVD, CNS, cancer and others. Given that the area of immunology/inflammation is highly complex (and especially so as it relates to radiation), it warrants the expansion of investigators expertise in immunology and inflammation to work with the individual research projects and also the NASA Specialized Center of Research (NSCORs). Historical data on radiation injury to be entered into the Watson �

Harmonization of risk management approaches: radiation and chemical exposures

Energy Technology Data Exchange (ETDEWEB)

Srinivasan, P. [Bhabha Atomic Research Centre, Radiation Safety Systems Div., Mumbai (India)

2006-07-01

Assessment of occupational and public risk from the environmental pollutants like chemicals, radiation, etc demands that the effects be considered not only from each individual pollutant, but from the combination of all the pollutants. An integrated risk assessment system needs to be in place to have an overall risk perspective for the benefit of policy makers and decision takers to try to achieve risk reduction in totality. The basis for risk-based radiation dose limits is derived from epidemiological studies, which provide a rich source of data largely unavailable to chemical risk assessors. In addition, use of the principle of optimization as expressed in the ALARA concept has resulted in a safety culture, which is much more than just complying with stipulated limits. The conservative hypothesis of no-threshold dose-effect relation (ICRP) is universally assumed. The end-points and the severity of different classes of pollutants and even different pollutants in a same class vary over a wide range. Hence, it is difficult to arrive at a quantitative value for the net detriment that weighs the various types of end-points and various classes of pollutants. Once the risk due to other pollutants is quantified by some acceptable methodology, it can be expressed in terms of the Risk Equivalent Radiation Dose (R.E.R.D.) for easy comparison with options involving radiation exposure. This paper is an effort to use to quantify and present the risk due to exposure to chemicals and radiation in a common scale for the purpose of easy comparison to facilitate decision taking. (authors)

Harmonization of risk management approaches: radiation and chemical exposures

International Nuclear Information System (INIS)

Srinivasan, P.

2006-01-01

Assessment of occupational and public risk from the environmental pollutants like chemicals, radiation, etc demands that the effects be considered not only from each individual pollutant, but from the combination of all the pollutants. An integrated risk assessment system needs to be in place to have an overall risk perspective for the benefit of policy makers and decision takers to try to achieve risk reduction in totality. The basis for risk-based radiation dose limits is derived from epidemiological studies, which provide a rich source of data largely unavailable to chemical risk assessors. In addition, use of the principle of optimization as expressed in the ALARA concept has resulted in a safety culture, which is much more than just complying with stipulated limits. The conservative hypothesis of no-threshold dose-effect relation (ICRP) is universally assumed. The end-points and the severity of different classes of pollutants and even different pollutants in a same class vary over a wide range. Hence, it is difficult to arrive at a quantitative value for the net detriment that weighs the various types of end-points and various classes of pollutants. Once the risk due to other pollutants is quantified by some acceptable methodology, it can be expressed in terms of the Risk Equivalent Radiation Dose (R.E.R.D.) for easy comparison with options involving radiation exposure. This paper is an effort to use to quantify and present the risk due to exposure to chemicals and radiation in a common scale for the purpose of easy comparison to facilitate decision taking. (authors)

Assessment of health risks from exposure to ionizing radiation

International Nuclear Information System (INIS)

Beebe, G.W.

1982-01-01

Rapid development in the assessment of health risks from exposure to ionizing radiation has produced an impressive array of risk differentials of presumed biologic significance. In the human data these differentials involve: (1) the variety of cancer, especially its size; (2) host factors, especially age; (3) time following exposure; (4) magnitude of dose; and (5) type of radiation. From experimental work we may presume that dose-rate also plays a role, especially for sparsely ionizing radiation. Current research is extending the scope of differentials with respect to these and other variables, including cell type and concomitant environmental risk factors, and testing dose-response models suggested by experimental and theoretical work. As facts to be explained, differentials in risk may lead to hypotheses to be explored experimentally and improve our understanding of how ionizing radiation causes cancer. 74 references

Special investigations of hemoglobin in the dynamics of acute radiation sickness

International Nuclear Information System (INIS)

Zdravko, B.J.; Panasyuk, E.N.

1986-01-01

The effect of penetrating radiation into the UV, visible and IR spectra of hemoglobin obtained from guinea-pigs being irradiated by the 300 and 600 cGy doses is studied. The change of the absorption intensity in the range of 275 nm of aqueous hemoglobin solutions depending on the stage and duration of the radiation pathology is revealed. The displacement of amide absorption bands into a shorter area of hemoglobin fluctuations frequencies of irradiated animals in the period from the 1 to 19-th day after the irradiation by the 300 cGy dose and during the whole period of the acute radiation pathology after the irradiation by the 600 cGy dose is established by the use of the IR-spectroscopy method. For the relative quantitative estimation of the denaturized hemoglobins by radiation, radiotoxins and by other physical and chemical factors, one suggests to use the formulas of the hem optical density relation coefficient to the globin optical density

Topical Calendula and Betamethasone Valerate in the prevention of acute radiation dermatitis: a randomized prospective trial

Directory of Open Access Journals (Sweden)

Fotouhi M

2007-07-01

Full Text Available Background: Acute radiation dermatitis is a very common side effect of radiation therapy for many cancers, including breast cancer. Despite the high prevalence of acute radiation dermatitis as well as wet desquamation, only a few trials studying the prophylaxis of this complication using topical treatment have been conducted. In spite of these studies, some controversy still exists about regarding treatments for acute radiation dermatitis, as does some concern about their long-term complications. For this reason, we conducted a clinical trial for a new treatment with the same effectiveness as corticosteroids, but fewer complications. Methods: This trial included 60 patients with pathologic diagnoses of breast cancer for whom radiotherapy had been planned. Patients were 30-73 years old. Patients with radical mastectomy received 5000 cGy over five weeks, and those with conservative surgery received 6000 cGy over six weeks divided in 200 cGy fractions. Patients were divided randomly into two groups: one group received a moderately-potent glucocorticoid steroid, 0.1% betamethasone ointment (30, and the other received the new treatment, 0.1% calendula ointment (30. All patients applied their respective drugs twice daily within the tangential field from the first day of radiation treatment until one month after treatment was completed. Starting one week after radiation therapy commenced, patients were monitored weekly for symptoms of dermatitis and the degree of severity as well as possible adverse drug effects, in addition to such monitoring on the days of their appointments. Four weeks after termination of therapy, patients were again examined, at which time they completed a questionnaire about dermatologic complications. Results: The mean time to develop dermatitis was 3.7 weeks for the betamethasone group and 3.87 weeks for the calendula group. Maximal dermatitis intensity during treatment in the betamethasone group was: 0, 6.7%; I, 73.3%; II, 16

Prophylactic and therapeutic management of acute radiation related morbidity of the skin and mucosa. Part I. Results of a German multicenter questionnaire

International Nuclear Information System (INIS)

Zimmermann, J.S.; Wilhelm, R.; Niehoff, P.; Schneider, R.; Kovacs, G.; Kimmig, B.

1998-01-01

In this work, it was to evaluate the remedies, which are used for prevention and therapeutic management of acute radiation related morbidity of the skin and mucosa (mouth, pharynx, esophagus, small and large bowel, rectum and vagina). A questionnaire was sent to 130 radiotherapeutic departments in Germany in Juli 1995. The questionnaire had been designed with 22 open questions concerning the preventive and therapeutic management of acute radiation related morbidity of skin and mucosal sites. From 130 questionnaires, 89 (68.4%) were sent back till August 1995. All of them were evaluable. The recommendations showed a broad spectrum for each site. Especially the oral mucositis was treated in many different ways and combinations. The prevention and therapy of complicating superinfections seem to be the joint principle of most of the recommendations. The management of the acute radiation related morbidity has a wide clinical spectrum among different radiation therapy centers. Systematic prospectively designed investigations are necessary in order to achieve a further reduction in the radiation related acute morbidity. Therefore, a multicenter collaborative working group has been founded. (orig./MG) [de

Physical performance following acute high-risk abdominal surgery

DEFF Research Database (Denmark)

Jønsson, Line Rokkedal; Ingelsrud, Lina Holm; Tengberg, Line Toft

2018-01-01

BACKGROUND: Acute high-risk abdominal (AHA) surgery is associated with high mortality, multiple postoperative complications and prolonged hospital stay. Further development of strategies for enhanced recovery programs following AHA surgery is needed. The aim of this study was to describe physical...... are primarily fatigue and abdominal pain. Further studies investigating strategies for early mobilization and barriers to mobilization in the immediate postoperative period after AHA surgery are needed.......BACKGROUND: Acute high-risk abdominal (AHA) surgery is associated with high mortality, multiple postoperative complications and prolonged hospital stay. Further development of strategies for enhanced recovery programs following AHA surgery is needed. The aim of this study was to describe physical...... performance and barriers to independent mobilization among patients who received AHA surgery (postoperative days [POD] 1-7). METHODS: Patients undergoing AHA surgery were consecutively enrolled from a university hospital in Denmark. In the first postoperative week, all patients were evaluated daily...

Radiation risks : the ethics of health protection

International Nuclear Information System (INIS)

Maxey, M.N.

1988-01-01

Since the inception of commercial uses of nuclear technology, radiation protection standards established by regulatory agencies have reflected moral concerns based on two assumptions: (1) that the linear, zero-threshold hypothesis derives from scientific data in radiobiology which are virtually conclusive; (2) it is morally better for public health protection to assume that any radiation exposure, no matter how small, has some harmful effect which can and ought to be prevented. In the past few years these beliefs and related assumptions have received closer scrutiny, revealing hidden reasons for regulatory selection of radiation risks as objects of paramount ethical concern, with the result that greater risks to health have escaped comparison and mitigation. Based on this scrutiny this brief paper explores two questions: Are presupposed assumptions ethically justified on grounds of scientific evidence and ethical consistency? and should moral objections claiming to invalidate comparative risk assessments be accepted or rejected?

Acute Toxicity Grade 3 and 4 After Irradiation in Children and Adolescents: Results From the IPPARCA Collaboration

Energy Technology Data Exchange (ETDEWEB)

Pixberg, Caroline [Department of Radiation Oncology, University Hospital of Muenster, Muenster (Germany); Koch, Raphael [Institute of Biostatistics and Clinical Research, University of Muenster, Muenster (Germany); Eich, Hans Theodor, E-mail: Hans.Eich@ukmuenster.de [Department of Radiation Oncology, University Hospital of Muenster, Muenster (Germany); Department of Radiation Oncology, University of Koeln, Koeln (Germany); Martinsson, Ulla [Department of Oncology, University Hospital, Uppsala (Sweden); Kristensen, Ingrid [Department of Radiation Physics, Skåne University Hospital, Lund (Sweden); Matuschek, Christiane [Department of Radiation Oncology, University Hospital of Duesseldorf, Duesseldorf (Germany); Kortmann, Rolf-Dieter [Department of Radiation Oncology, University Hospital of Leipzig, Leipzig (Germany); Pohl, Fabian [Department of Radiation Oncology, University of Regensburg, Regensburg (Germany); Elsayad, Khaled [Department of Radiation Oncology, University Hospital of Muenster, Muenster (Germany); Christiansen, Hans [Department of Radiation Oncology, Medical School Hannover, Hannover (Germany); Willich, Normann [Department of Radiation Oncology, University Hospital of Muenster, Muenster (Germany); Lindh, Jack [Department of Radiation Sciences, Umeå University, Umeå (Sweden); Steinmann, Diana [Department of Radiation Oncology, University Hospital of Muenster, Muenster (Germany); Department of Radiation Oncology, Medical School Hannover, Hannover (Germany)

2016-03-15

Purpose: In the context of oncologic therapy for children, radiation therapy is frequently indicated. This study identified the frequency of and reasons for the development of high-grade acute toxicity and possible sequelae. Materials and Methods: Irradiated children have been prospectively documented since 2001 in the Registry for the Evaluation of Side Effects After Radiation in Childhood and Adolescence (RiSK) database in Germany and since 2008 in the registry for radiation therapy toxicity (RADTOX) in Sweden. Data were collected using standardized, published forms. Toxicity classification was based on Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Results: As of June 2013, 1500 children have been recruited into the RiSK database and 485 into the RADTOX registry leading to an analysis population of 1359 patients (age range 0-18). A total of 18.9% (n=257) of all investigated patients developed high-grade acute toxicity (grades 3/4). High-grade toxicity of the bone marrow was documented for 63.8% (n=201) of those patients, oral mucositis for 7.6% (n=24), and dermatitis for 7.6% (n=24). Patients with high-grade acute toxicity received concomitant chemotherapy more frequently (56%) than patients with no or lower acute toxicity (31.5%). In multivariate analyses, concomitant chemotherapy, diagnosis of Ewing sarcoma, and total radiation dose showed a statistically noticeable effect (P≤.05) on acute toxicity, whereas age, concomitant chemotherapy, Hodgkin lymphoma, Ewing sarcoma, total radiation dose, and acute toxicity influenced the time until maximal late toxicity. Conclusions: Generally, high-grade acute toxicity after irradiation in children and adolescence occurs in a moderate proportion of patients (18.9%). As anticipated, the probability of acute toxicity appeared to depend on the prescribed dose as well as concomitant chemotherapy. The occurrence of chronic toxicity correlates with the prior acute

Radiation as a source of risk

International Nuclear Information System (INIS)

Katoh, Kazuaki

1999-01-01

Essence and nature of ionizing radiation as a source of risk are reviewed. Following to the appeal of necessity and importance of campaign for enlightening risk management, of individual and of society, background knowledge and information helpful to the promotion and discussion are summarized, also. (author)

Radiation risk analysis of tritium in PWR plants

International Nuclear Information System (INIS)

Yang Maochun; Wang Shimin

1999-03-01

Tritium is a common radionuclide in PWR nuclear power plant. In the normal operation conditions, its radiation risk to plant workers is the internal radiation exposure when tritium existing in air as HTO (hydrogen tritium oxide) is breathed in. As the HTO has the same physical and chemical characteristics as water, the main way that HTO entering the air is by evaporation. There are few opening systems in Nuclear Power Plant, the radiation risk of tritium mainly exists near the area of spent fuel pit and reactor pit. The highest possible radiation risk it may cause--the maximum concentration in air is the level when equilibrium is established between water and air phases for tritium. The author analyzed the relationship among the concentration of HTO in water, in air and the water temperature when equilibrium is established, the equilibrated HTO concentration in air increases with HTO concentration in water and water temperature. The analysis revealed that at 30 degree C, the equilibrated HTO concentration in air might reach 1 DAC (derived air concentration) when the HTO concentration in water is 28 GBq/m 3 . Owing to the operation of plant ventilation systems and the existence of moisture in the input air of the ventilation, the practical tritium concentration in air is much lower than its equilibrated levels, the radiation risk of tritium in PWR plant is quite limited. In 1997, Daya Bay Nuclear Power Plant's practical monitoring result of the HTO concentration in the air of the nuclear island and the urine of workers supported this conclusion. Based on this analysis, some suggestions to the reduction of tritium radiation risk were made

Real and perceived risks of medical radiation exposure

International Nuclear Information System (INIS)

Hendee, W.R.

1983-01-01

After considering all the evidence related to the health effects of exposure to low levels of radiation, it is apparent that the risk is immeasurably small to any single person in a population exposed to small amounts of radiation. However, multiplying this immeasurably small estimate of risk by very large populations yields numbers that seem to imply that significant health effects (cancer, malformations, genetic effects) occur following exposure to small quantities of radiation. Although many advisory groups have cautioned against this procedure and conclusion, both continue to be used by some scientists and political action groups. In a public opinion poll conducted by Decision Research, Inc. of Eugene, Oregon, three groups were asked to rank the relative risks of various societal activities. Two of the three groups ranked nuclear power as the most hazardous of all societal activities, with a risk factor greater than that for smoking, automobiles, handguns and alcohol. Actually, nuclear power is the least hazardous of all 30 of the activities included in the poll. It is a conservative posture and probably a wise course of action to assume that exposure to any amount of radiation carries with it some element of risk. For example, requests for x-ray studies and nuclear medicine procedures should always be accompanied by an appreciation of the possibility of risk to the patient and to radiological personnel. At the same time, this element of risk should be placed in a realistic perspective by comparing it with other risks we assume every day

Establishment and evolution of the radiation risk concept for the man and human population in the 20th century

International Nuclear Information System (INIS)

Vassilev, G.; Hadjieva

2003-01-01

The concept of radiation risk (RR) is the main basis for human protection from the harmful effect of ionizing radiation. It concerns the expected unfavorable health effects upon the irradiated person and probably upon his/her progeny. The early period of the history of RR evaluation was grounded on the assessment of acute skin reactions (erythema, epilation, dermatitis, ulceration) and on the measures (erythema dose) taken to diminish them. The second period covers the appraisal, based on estimation of different somatic effects and expected heredity ( genetic effects). They could be avoided if irradiation does not exceed the maximum permissible dose - the concept of zero RR. The current (third) period estimates both irradiation effects: deterministic effects that have a dose-related threshold and stochastic non-threshold effects. The ultimate goal of radiation protection is to exclude all deterministic effects and to diminish probability of stochastic effects (carcinogenesis and heredity effects) down to an acceptable level. Seven postulates describe the modern concept of RR for the man and human population: globalization irreversibility, accumulation, non-threshold harm, stochastic, non-specificity and acceptance of the risk

Radiation effects, nuclear energy and comparative risks

International Nuclear Information System (INIS)

Gopinath, D.V.

2007-01-01

Nuclear energy had a promising start as an unlimited, inexpensive and environmentally benign source of energy for electricity generation. However, over the decades its growth was severely retarded due to concerns about its possible detrimental effects on the well-being of mankind and the environment. Since such concerns are essentially due to the gigantic magnitude of radioactivity and ionizing radiations associated with nuclear energy, this article starts with a comprehensive account of effects of the ionizing radiation on living systems. Quantitative description of types of radiation exposure and their varied effects is given. The origin, type and magnitude of mutagenic effects of radiation are described. The concept of radiation risk factors, basis for their evaluation and their currently accepted values are presented. With this background, origin and magnitude of radioactivity and associated ionizing radiations in nuclear reactors are presented and the elaborate measures to contain them are described. It is recognized that notwithstanding all the measures taken in the nuclear industry, certain amount of radiation exposure, however small, is inevitable and the values, based on the experience world over, are presented. Estimated health risk due to such exposures is evaluated. For a comparative analysis, risks in other options of electricity generation such as hydel and fossil-fuelled plants are described. It is seen that on an overall basis, the nuclear option is no more risky than the other commonly employed options, and is in fact, significantly less. Lastly, since every option of electricity generation entails some risk, the case of 'no addition of electricity, and its impact on the society are considered. Based on the analysis of extensive data provided by UNDP on the human development parameters for different countries in the world, it is shown that at least for developing countries, any option of addition of electricity would be far more desirable than the

Natural radiation, radioactive waste and chemical risk determinants

International Nuclear Information System (INIS)

Christensen, T.; Mustonen, R.; Edhwall, H.; Hansen, H.; Soerensen, A.; Stranden, E.

1990-01-01

Doses from natural radiation to the population in the Nordic countries are summarized, and man-made modifications of the natural radiation environment are discussed. An account is given for the radiological concequences of energy concervation by reduced ventilation. Risks from possible future releases of radioactivity from final depositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. 104 refs., 36 figs., 47 tabs

Curcumin protects against radiation-induced acute and chronic cutaneous toxicity in mice and decreases mRNA expression of inflammatory and fibrogenic cytokines

International Nuclear Information System (INIS)

Okunieff, Paul; Xu Jianhua; Hu Dongping; Liu Weimin; Zhang Lurong; Morrow, Gary; Pentland, Alice; Ryan, Julie L.; Ding, Ivan M.D.

2006-01-01

Purpose: To determine whether curcumin ameliorates acute and chronic radiation skin toxicity and to examine the expression of inflammatory cytokines (interleukin [IL]-1, IL-6, IL-18, IL-1Ra, tumor necrosis factor [TNF]-α, and lymphotoxin-β) or fibrogenic cytokines (transforming growth factor [TGF]-β) during the same acute and chronic phases. Methods and Materials: Curcumin was given intragastrically or intraperitoneally to C3H/HeN mice either: 5 days before radiation; 5 days after radiation; or both 5 days before and 5 days after radiation. The cutaneous damage was assessed at 15-21 days (acute) and 90 days (chronic) after a single 50 Gy radiation dose was given to the hind leg. Skin and muscle tissues were collected for measurement of cytokine mRNA. Results: Curcumin, administered before or after radiation, markedly reduced acute and chronic skin toxicity in mice (p < 0.05). Additionally, curcumin significantly decreased mRNA expression of early responding cytokines (IL-1 IL-6, IL-18, TNF-α, and lymphotoxin-β) and the fibrogenic cytokine, TGF-β, in cutaneous tissues at 21 days postradiation. Conclusion: Curcumin has a protective effect on radiation-induced cutaneous damage in mice, which is characterized by a downregulation of both inflammatory and fibrogenic cytokines in irradiated skin and muscle, particularly in the early phase after radiation. These results may provide the molecular basis for the application of curcumin in clinical radiation therapy

Ionizing radiation risks to satellite power systems (SPS) workers

International Nuclear Information System (INIS)

1980-11-01

The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities

Ionizing radiation risks to satellite power systems (SPS) workers

Energy Technology Data Exchange (ETDEWEB)

Lyman, J.T.; Ainsworth, E.J.; Alpen, E.L.; Bond, V.; Curtis, S.B.; Fry, R.J.M.; Jackson, K.L.; Nachtwey, S.; Sondhaus, C.; Tobias, C.A.; Fabrikant, J.I.

1980-11-01

The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities.

Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1981-01-01

The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain, for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy

Differential diagnosis of the acute abdomen. Pt. 4. Acute abdomen in children; Differenzialdiagnose des akuten Abdomens. T. 4. Akutes Abdomen im Kindesalter

Energy Technology Data Exchange (ETDEWEB)

Staatz, Gundula [Universitaetsklinikum Mainz (Germany). Sektion Kinderradiologie; Schneider, Karl [Klinikum der Univ. Muenchen (Germany). Abt. Radiologie

2010-06-15

The diagnostic work-up of adults with acute abdominal pain has changed significantly within the last decade and computed tomography is often used as the first imaging modality of choice. In pediatric patients with an acute abdomen, ultrasound and abdominal X-rays remain the first line procedures. Because of the radiation risk, computed tomography is only recommended in selected cases and when strongly indicated. This review is the fourth and final part within a series of reviews dealing with the diagnostic strategy in the work-up of patients with an acute abdomen. (orig.)

Risk assessment of radiation carcinogenesis

International Nuclear Information System (INIS)

Kai, Michiaki

2012-01-01

This commentary describes the radiation cancer risk assessed by international organizations other than ICRP, assessed for radon and for internal exposure, in the series from the aspect of radiation protection of explaining the assessments done until ICRP Pub. 103. Statistic significant increase of cancer formation is proved at higher doses than 100-200 mSv. At lower doses, with use of mathematical model, United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reported the death probability due to the excess lifetime risk (ELR) at 100 mSv of 0.36-0.77% for solid tumors and 0.03-0.05% for leukemia, and NRC in US, the risk of exposure-induced prevalence and death (REID) per 100 thousands persons of 800 (male)/1,310 (female) and 410/610, respectively. Both are essentially based on findings in A-bomb survivors. The assessment for Rn is described here not on dose. UK and US analyses of pooled raw data in case control studies revealed the significant increase of lung cancer formation at as low level as 100 Bq Rn/m3. Their analyses also showed the significance of smoking, which had been realized as a confounding factor in risk analysis of Rn for uranium miners. The death probability until the age of 85 y was found to be 1.2 x 10 -4 in non-smokers and 24 x 10 -4 in smokers/ Working Level Month (WLM). Increased thyroid cancer incidence has been known in Chernobyl Accident, which is realized as a result of internal exposure of radioiodine; however, the relationship between the internal dose to thyroid and its cancer prevalence resembles that in the case of external exposure. There is no certain evidence against the concept that risk of internal exposure is similar to and/or lower than, the external one although assessment of the internal exposure risk accompanies uncertainty depending on the used model and ingested dose. International Commission on Radiological Protection (ICRP) recommendations hitherto have been important and precious despite

Risks Associated with Ionizing Radiations

International Nuclear Information System (INIS)

Cascon, Adriana

2009-01-01

Medical use of ionizing radiations implies certain risks which are widely balanced by their diagnostic and therapeutic benefits. Nevertheless, knowledge about these risks and how to diagnose and prevent them minimizes their disadvantages and optimizes the quality and safety of the method. This article describes the aspects related to skin dose (nonstochastic effects), the importance of dose limit, the physiopathology of biological damage and, finally, the prevention measures. [es

Identifying and managing the risks of medical ionizing radiation in endourology.

Science.gov (United States)

Yecies, Todd; Averch, Timothy D; Semins, Michelle J

2018-02-01

The risks of exposure to medical ionizing radiation is of increasing concern both among medical professionals and the general public. Patients with nephrolithiasis are exposed to high levels of ionizing radiation through both diagnostic and therapeutic modalities. Endourologists who perform a high-volume of fluoroscopy guided procedures are also exposed to significant quantities of ionizing radiation. The combination of judicious use of radiation-based imaging modalities, application of new imaging techniques such as ultra-low dose computed tomography (CT) scan, and modifying use of current technology such as increasing ultrasound and pulsed fluoroscopy utilization offers the possibility of significantly reducing radiation exposure. We present a review of the literature regarding the risks of medical ionizing radiation to patients and surgeons as it pertains to the field of endourology and interventions that can be performed to limit this exposure. A review of the current state of the literature was performed using MEDLINE and PubMed. Interventions designed to limit patient and surgeon radiation exposure were identified and analyzed. Summaries of the data were compiled and synthesized in the body of the text. While no level 1 evidence exists demonstrating the risk of secondary malignancy with radiation exposure, the preponderance of evidence suggests a dose and age dependent increase in malignancy risk from ionizing radiation. Patients with nephrolithiasis were exposed to an average effective dose of 37mSv over a 2 year period. Multiple evidence-based interventions to limit patient and surgeon radiation exposure and associated risk were identified. Current evidence suggest an age and dose dependent risk of secondary malignancy from ionizing radiation. Urologists must act in accordance with ALARA principles to safely manage nephrolithiasis while minimizing radiation exposure.

Doses of low level ionizing radiation; a misunderstood risk, however unavoidable

International Nuclear Information System (INIS)

Nicolli, D.

1988-01-01

The treatment given by international organizations and associations to the problems of radiation exposures, and the recommendations and norms for calculating risks of low level radiation are analysed. It is shown that there are not zero risks for nuclear energy, and emphasis is given to the risks of natural radiation from environment. (M.C.K.) [pt

Radiation risks -a possible teaching topic

International Nuclear Information System (INIS)

Howes, R.W.

1975-01-01

Radiation risks has been the subject of hot debate since 1969 due in main to the energy crisis and the switch to nuclear power. Topics of this debate including; the controversy concerned with the late radiobiological effects of low level radiation, the social responsibility of modern scientists, the sometimes acrimonious discussion which has taken place over many years concerning radiation standards, and present day misgivings over the environmental aspect of the nuclear power programme, are discussed and suggestions are made of ways in which the topics could be introduced into teaching courses. (U.K.)

The stratification of severity of acute radiation proctopathy after radiotherapy for cervical carcinoma using diffusion-weighted MRI

Energy Technology Data Exchange (ETDEWEB)

Li, Xiang Sheng, E-mail: lxsheng500@163.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Fang, Hong, E-mail: hongfang196808@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Song, Yunlong, E-mail: yunlongsong010@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Li, Dechang, E-mail: dechangli1972@sina.com [Department of Pathology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Yingjie, E-mail: wangyj19710813@sina.com [Department of Radiotherapy, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Zhu, Hongxian, E-mail: hongxian0102@sina.cn [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Meng, Limin, E-mail: liminmeng1977@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Ping, E-mail: pingwang1978@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Dong, E-mail: dongwang1964@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Fan, Hongxia, E-mail: fanhongxia1975@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China)

2017-02-15

Objective: To determine whether diffusion-weighted imaging (DWI) can be used for quantitatively evaluating severity of acute radiation proctopathy after radiotherapy for cervical carcinoma. Materials and methods: One hundred and twenty-four patients with cervical carcinoma underwent MR examination including DWI before and after radiotherapy. Acute radiation proctopathy was classified into three groups (grade 0, grade I–II and grade III–IV) according to Toxicity Criteria of the Radiation Therapy Oncology Group (RTOG). The pretreatment ADC (ADC{sub pre}), ADC after treatment (ADC{sub post}) and ADC change (ΔADC) were compared among three groups. In addition, acute radiation proctopathy was classified into good-prognosis group and poor-prognosis group. ADC{sub pre}, ADC{sub post} and ΔADC were compared between two groups. For DWI parameter that had significant difference, discriminatory capability of the parameter was determined using receiver operating characteristics (ROC) analysis. Results: ADC{sub post} and ΔADC were higher in grade I–II group than in grade 0 group (p < 0.05), yielding a sensitivity of 79.3% and specificity of 69.4% for ADC{sub post}, and 85.1%, 72.3% for ΔADC for discrimination between two groups. ADC{sub post} and ΔADC were higher in grade III–IV group than in grade I–II group (p < 0.05), yielding a sensitivity of 80.3% and specificity of 72.5% for ADC{sub post}, and 84.1%, 74.5% for ΔADC for discrimination between two groups. ADC{sub post} and ΔADC were higher in poor-prognosis group than in good-prognosis group (p < 0.05), yielding a sensitivity of 79.5% and specificity of 73.4% for ADC{sub post}, and 87.2%, 78.3% for ΔADC for discrimination between two groups. Conclusion: Diffusion-weighted MRI can be used for quantitative stratification of severity of acute radiation proctopathy, which serves as an important basis for appropriate timely adjustment of radiotherapy for cervical carcinoma in order to maximally reduce the

Topical betamethasone for the prevention of acute radiation dermatitis in breast cancer patients

International Nuclear Information System (INIS)

Farhan, F.; Kazemian, A.; Alagheband, H.

2003-01-01

Background: Acute radiation dermatitis is a very common side effect of radiation therapy in large numbers of cancers including breast cancer. Despite high prevalence rate of acute radiation dermatitis and also wet desquamation, a few trials on prophylaxis of this complication using topical treatment have been conducted. Despite effectiveness of topical corticosteroids in treatment of acute radiation dermatitis which are focused in the literature, yet there are some controversy about their usage in this regard. For this reason we attempted to investigate this subject via conducting a clinical trial. Materials and Methods: This trial included 76 patients with pathologic diagnosis of breast cancer for whom radiotherapy has been planned. Patients were 27-70 years old. Patients with radical mastectomy received 5000 cGy within 5 weeks, and those with conservative surgery received 6000 cGy within 6 weeks devided in 200 centigray fractions. Patients were divided randomly into two groups, betamethasone and placebo, 38 patients in each group. In placebo group, 3 patients did not attend for weekly assessment. Additional one patient did not refer during follow-up period. Thus, they were excluded from the study. One group was given betamethasone o.1% and other group was administered base of ointment as placebo. All patient consumed drug or placebo from the 1st day of treatment until one week after treatment completion as twice daily within tangential field. Patients were monitored for assessing dermatitis severity and its symptoms and also possible drug adverse effects one week after the therapy commenced and afterwards by one-week intervals as well as in an appointed day. Three weeks after termination of therapy, patients were also visited, and each examination provided information about dermatologic complications which were registered in the questionnaire. Results: Mean times development of dermatitis in both betamethasone and placebo groups were 3.2500 and 2.2571 (weeks

Total Risk Management for Low Dose Radiation Exposures

International Nuclear Information System (INIS)

Simic, Z.; Mikulicic, V.; Sterc, D.

2012-01-01

Our civilization is witnessing about century of nuclear age mixed with enormous promises and cataclysmic threats. Nuclear energy seems to encapsulate both potential for pure good and evil or at least we humans are able to perceive that. These images are continuously with us and they are both helping and distracting from making best of nuclear potentials for civilization. Today with nuclear use significantly present and with huge potential to further improve our life with energy and medical use it is of enormous importance to try to have calmed, rational, and objective view on potential risks and certain benefits. Because all use of nuclear energy proved that their immediate risks are negligible (i.e., Three Mile Island and Fukushima) or much smaller than from the other alternatives (i.e., Chernobyl) it seems that the most important issue is the amount of risk from the long term effects to people from exposure to small doses of radiation. A similar issue is present in the increased use of modern computational tomography and other radiation sources use in medicine for examination and therapy. Finally, extreme natural exposures are third such potential risk sources. Definition of low doses varies depending on the way of delivery (i.e., single, multiple or continuous exposures), and for this paper usual dose of 100 mSv is selected as yearly upper amount. There are three very different scientifically supported views on the potential risks from the low doses exposure. The most conservative theory is that all radiation is harmful, and even small increments from background levels (i.e., 2-3 mSv) present additional risk. This view is called linear no threshold theory (LNT) and it is accepted as a regulatory conservative simple approach which guarantees safety. Risk is derived from the extrapolation of the measured effects of high levels of radiation. Opposite theory to LNT is hormesis which assumes that in fact small doses of radiation are helpful and they are improving our

Occuptional radiation exposures and thyroid cancer risk among radiologic technologists

Energy Technology Data Exchange (ETDEWEB)

Moon, Eun Kyeong; Lee, Won Jin [Korea University, Seoul (Korea, Republic of); Ha, Mina [Dankook University Seoul (Korea, Republic of); Kim, Jae Young [Keimyung University, Daegu (Korea, Republic of); Jun, Jae Kwan [National Cancer Center, Seoul (Korea, Republic of); Jin, Young Won [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2016-04-15

Medical radiation workers were among the earliest occupational groups exposed to external ionizing radiation due to their administration of a range of medical diagnostic procedures and accounted for 7.4 million worldwide in 2008. Ionizing radiation is the confirmed human carcinogen for most organ sites. The aims of the study is to evaluate the association between occupational practices including radiation exposure and thyroid cancer risk among radiologic technologists. We found no significant association between the risk of thyroid cancer and the majority of work practices among diagnostic radiation technologists in general. However workers performing fluoroscopy and interventional procedures showed increased risks although the lack of a clear exposure– response gradient makes it difficult to draw clear conclusions. Future studies with larger sample size and detailed work practices implementation are needed to clarify the role of occupational radiation work in thyroid cancer carcinogenesis.

Occuptional radiation exposures and thyroid cancer risk among radiologic technologists

International Nuclear Information System (INIS)

Moon, Eun Kyeong; Lee, Won Jin; Ha, Mina; Kim, Jae Young; Jun, Jae Kwan; Jin, Young Won

2016-01-01

Medical radiation workers were among the earliest occupational groups exposed to external ionizing radiation due to their administration of a range of medical diagnostic procedures and accounted for 7.4 million worldwide in 2008. Ionizing radiation is the confirmed human carcinogen for most organ sites. The aims of the study is to evaluate the association between occupational practices including radiation exposure and thyroid cancer risk among radiologic technologists. We found no significant association between the risk of thyroid cancer and the majority of work practices among diagnostic radiation technologists in general. However workers performing fluoroscopy and interventional procedures showed increased risks although the lack of a clear exposure– response gradient makes it difficult to draw clear conclusions. Future studies with larger sample size and detailed work practices implementation are needed to clarify the role of occupational radiation work in thyroid cancer carcinogenesis.

BiodosEPR-2006 Meeting: Acute dosimetry consensus committee recommendations on biodosimetry applications in events involving uses of radiation by terrorists and radiation accidents

Energy Technology Data Exchange (ETDEWEB)

Alexander, George A. [U.S. Department of Health and Human Services, Office of Preparedness and Emergency Operations, 200 Independence Avenue, SW, Room 403B-1, Washington, DC 20201 (United States); Swartz, Harold M. [Dept. of Radiology and Physiology Dept., Dartmouth Medical School, HB 7785, Vail 702, Rubin 601, Hanover, NH 03755 (United States); Amundson, Sally A. [Center for Radiological Research, Columbia University Medical Center, 630 W. 168th Street, VC11-215, New York, NY 10032 (United States); Blakely, William F. [Armed Forces Radiobiology Research Inst., 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)], E-mail: blakely@afrri.usuhs.mil; Buddemeier, Brooke [Science and Technology, U.S. Department of Homeland Security, Washington, DC 20528 (United States); Gallez, Bernard [Biomedical Magnetic Resonance Unit and Lab. of Medicinal Chemistry and Radiopharmacy, Univ. Catholique de Louvain, Brussels (Belgium); Dainiak, Nicholas [Dept. of Medicine, Bridgeport Hospital, 267 Grant Street, Bridgeport, CT 06610 (United States); Goans, Ronald E. [MJW Corporation, 1422 Eagle Bend Drive, Clinton, TN 37716-4029 (United States); Hayes, Robert B. [Remote Sensing Lab., MS RSL-47, P.O. Box 98421, Las Vegas, NV 89193 (United States); Lowry, Patrick C. [Radiation Emergency Assistance Center/Training Site (REAC/TS), Oak Ridge Associated Universities, P.O. Box 117, Oak Ridge, TN 37831-0117 (United States); Noska, Michael A. [Food and Drug Administration, FDA/CDRH, 1350 Piccard Drive, HFZ-240, Rockville, MD 20850 (United States); Okunieff, Paul [Dept. of Radiation Oncology (Box 647), Univ. of Rochester, 601 Elmwood Avenue, Rochester, NY 14642 (United States); Salner, Andrew L. [Helen and Harry Gray Cancer Center, Hartford Hospital, 80 Seymour Street, Hartford, CT 06102 (United States); Schauer, David A. [National Council on Radiation Protection and Measurements, 7910 Woodmont Avenue, Suite 400, Bethesda, MD 20814-3095 (United States)] (and others)

2007-07-15

In the aftermath of a radiological terrorism incident or mass-casualty radiation accident, first responders and receivers require prior guidance and pre-positioned resources for assessment, triage and medical management of affected individuals [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA]. Several recent articles [Dainiak, N., Waselenko, J.K., Armitage, J.O., MacVittie, T.J., Farese, A.M., 2003. The hematologist and radiation casualties. Hematology (Am. Soc. Hematol. Educ. Program) 473-496; Waselenko, J.K., MacVittie, T.J., Blakely, W.F., Pesik, N., Wiley, A.L., Dickerson, W.E., Tsu, H., Confer, D.L., Coleman, C.N., Seed, T., Lowry, P., Armitage, J.O., Dainiak, N., Strategic National Stockpile Radiation Working Group, 2004. Medical management of the acute radiation syndrome: recommendations of the Strategic National Stockpile Radiation Working Group. Ann. Intern. Med. 140(12), 1037-1051; Blakely, W.F., Salter, C.A., Prasanna, P.G., 2005. Early-response biological dosimetry-recommended countermeasure enhancements for mass-casualty radiological incidents and terrorism. Health Phys. 89(5), 494-504; Goans, R.E., Waselenko, J.K., 2005. Medical management of radiation casualties. Health Phys. 89(5), 505-512; Swartz, H.M., Iwasaki, A., Walczak, T., Demidenko, E., Salikhov, I., Lesniewski, P., Starewicz, P., Schauer, D., Romanyukha, A., 2005. Measurements of clinically significant doses of ionizing radiation using non-invasive in vivo EPR spectroscopy of teeth in situ. Appl. Radiat. Isot. 62, 293-299; . Acute radiation injury: contingency planning for triage, supportive care, and transplantation. Biol. Blood Marrow Transplant. 12(6), 672-682], national [. Management of persons accidentally contaminated with radionuclides. NCRP Report No. 65, Bethesda, Maryland, USA; . Management of terrorist events involving radioactive material. NCRP Report No. 138, Bethesda, Maryland

BiodosEPR-2006 Meeting: Acute dosimetry consensus committee recommendations on biodosimetry applications in events involving uses of radiation by terrorists and radiation accidents

International Nuclear Information System (INIS)

Alexander, George A.; Swartz, Harold M.; Amundson, Sally A.; Blakely, William F.; Buddemeier, Brooke; Gallez, Bernard; Dainiak, Nicholas; Goans, Ronald E.; Hayes, Robert B.; Lowry, Patrick C.; Noska, Michael A.; Okunieff, Paul; Salner, Andrew L.; Schauer, David A.

2007-01-01

In the aftermath of a radiological terrorism incident or mass-casualty radiation accident, first responders and receivers require prior guidance and pre-positioned resources for assessment, triage and medical management of affected individuals [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA]. Several recent articles [Dainiak, N., Waselenko, J.K., Armitage, J.O., MacVittie, T.J., Farese, A.M., 2003. The hematologist and radiation casualties. Hematology (Am. Soc. Hematol. Educ. Program) 473-496; Waselenko, J.K., MacVittie, T.J., Blakely, W.F., Pesik, N., Wiley, A.L., Dickerson, W.E., Tsu, H., Confer, D.L., Coleman, C.N., Seed, T., Lowry, P., Armitage, J.O., Dainiak, N., Strategic National Stockpile Radiation Working Group, 2004. Medical management of the acute radiation syndrome: recommendations of the Strategic National Stockpile Radiation Working Group. Ann. Intern. Med. 140(12), 1037-1051; Blakely, W.F., Salter, C.A., Prasanna, P.G., 2005. Early-response biological dosimetry-recommended countermeasure enhancements for mass-casualty radiological incidents and terrorism. Health Phys. 89(5), 494-504; Goans, R.E., Waselenko, J.K., 2005. Medical management of radiation casualties. Health Phys. 89(5), 505-512; Swartz, H.M., Iwasaki, A., Walczak, T., Demidenko, E., Salikhov, I., Lesniewski, P., Starewicz, P., Schauer, D., Romanyukha, A., 2005. Measurements of clinically significant doses of ionizing radiation using non-invasive in vivo EPR spectroscopy of teeth in situ. Appl. Radiat. Isot. 62, 293-299; . Acute radiation injury: contingency planning for triage, supportive care, and transplantation. Biol. Blood Marrow Transplant. 12(6), 672-682], national [. Management of persons accidentally contaminated with radionuclides. NCRP Report No. 65, Bethesda, Maryland, USA; . Management of terrorist events involving radioactive material. NCRP Report No. 138, Bethesda, Maryland

Comments on the theory of radiation risk I Systematic outline of the theory of radiation risk

CERN Document Server

Neufeld, J

1974-01-01

Presents a systematic outline of the current theory of radiation risk. The most basic ideas of the theory can be expressed by two quantities which represent the administrative approach to radiation risk. These quantities are 'specific dose', D/sub s/, which relates to individual organs or tissues and 'overall dose', D/sub 0/, which relates to the entire human body. By taking D/sub s/ and D/sub 0/ as a starting point and by using postulational methods, two auxiliary quantities have been derived which are 'dose equivalent', D/sub e/(r), and quality factor, Q. Dose equivalent, D/sub e/(r), is a macroscopic field quantity and is, therefore, different from the ICRP defined dose equivalent, H, which is microscopic.

Clinical report of three cases of acute radiation sickness from a 60Co radiation accident in Henan Province in China

International Nuclear Information System (INIS)

Liu Qiang; Jiang Bo; Jiang Liping; Wu Ying; Wang Xiaoguang; Jiang Enhai; Zhao Fengling; Fu Baohua; Istvan, Turai

2008-01-01

On 26 April 1999, three persons were accidentally exposed by high dose 60 Co irradiation. They suffered from severe (one case) or moderate (two cases) hemopoietic form of acute radiation sickness (ARS). As part of the comprehensive treatment, strict reverse isolation and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy were applied. All the patients recovered after an appropriate treatment for 83 days. In our experience, the correct diagnosis and effective treatment at an early stage proved to be helpful to the patients in pulling out from the critical stage of acute radiation sickness. To avoid menstruation by the female patient just in the critical stage, we modified her menstruation cycle by testosterone. In our view, GM-CSF should be given as early as possible with enough dosage for promoting early hematological reconstruction. The experience obtained from the medical management of these patients is valuable for the treatment of such patients in the future. (author)

Space Radiation Heart Disease Risk Estimates for Lunar and Mars Missions

Science.gov (United States)

Cucinotta, Francis A.; Chappell, Lori; Kim, Myung-Hee

2010-01-01

The NASA Space Radiation Program performs research on the risks of late effects from space radiation for cancer, neurological disorders, cataracts, and heart disease. For mortality risks, an aggregate over all risks should be considered as well as projection of the life loss per radiation induced death. We report on a triple detriment life-table approach to combine cancer and heart disease risks. Epidemiology results show extensive heterogeneity between populations for distinct components of the overall heart disease risks including hypertension, ischaemic heart disease, stroke, and cerebrovascular diseases. We report on an update to our previous heart disease estimates for Heart disease (ICD9 390-429) and Stroke (ICD9 430-438), and other sub-groups using recent meta-analysis results for various exposed radiation cohorts to low LET radiation. Results for multiplicative and additive risk transfer models are considered using baseline rates for US males and female. Uncertainty analysis indicated heart mortality risks as low as zero, assuming a threshold dose for deterministic effects, and projections approaching one-third of the overall cancer risk. Medan life-loss per death estimates were significantly less than that of solid cancer and leukemias. Critical research questions to improve risks estimates for heart disease are distinctions in mechanisms at high doses (>2 Gy) and low to moderate doses (<2 Gy), and data and basic understanding of radiation doserate and quality effects, and individual sensitivity.

[Ionizing and non-ionizing radiation (comparative risk estimations)].

Science.gov (United States)

Grigor'ev, Iu G

2012-01-01

The population has widely used mobile communication for already more than 15 years. It is important to note that the use of mobile communication has sharply changed the conditions of daily exposure of the population to EME We expose our brain daily for the first time in the entire civilization. The mobile phone is an open and uncontrollable source of electromagnetic radiation. The comparative risk estimation for the population of ionizing and non-ionizing radiation was carried out taking into account the real conditions of influence. Comparison of risks for the population of ionizing and non-ionizing radiation leads us to a conclusion that EMF RF exposure in conditions of wide use of mobile communication is potentially more harmful than ionizing radiation influence.

Biological effects of nuclear war: Acute effects of radiation; the LD-50 value

International Nuclear Information System (INIS)

Ohkita, T.; Rotblat, J.

1987-01-01

Recent surveys carried out in Japan in connection with the reassessment of the dosimetry for long-term effects provided an opportunity for another look at the acute effects of radiation and a recalculation of the LD-50 value. The recalculation gave an LD-50 value which is two to three times lower than had been assumed before. It means that in a nuclear war the number of fatalities due to exposure to radiation would be considerably higher than thought hitherto. 11 refs, 5 figs, 2 tabs

A mathematical foundation for controlling radiation health risks

International Nuclear Information System (INIS)

Kumazawa, S.

2000-01-01

Radiation protection is to attain an adequate control of radiation health risk compared with other risks. Our society in the 21 st century is predicted by some experts to seek the high priority of safety for expanding activity of human beings. The law of controlling risks will be a key subject to serve the safety of human beings and their environment. The main principles of the ICRP system of radiological system are strongly relating to the general law of various risk controls. The individual-based protection concept clearly gives us a mathematical model of controlling risks in general. This paper discusses the simplest formulation of controlling risks in the ICRP system, including other relating systems. First, the basic characteristics of occupational exposure as a risk control is presented by analyzing the data compiled over half a century. It shows the relation ship between dose control levels and individually controlled doses. The individual-based control also exerts some influence on the resultant collective dose. The study of occupational exposure concludes the simple mathematical expression of controlling doses under the ICRP system as shown by Kumazawa and Numakunai. Second, the typical characteristics of biological effects with repair or recovery of bio-systems are given by analyzing the data published. Those show the relationship between dose and biologically controlled or regulated response. The bio-system is undoubtedly relating to cybernetics that contains many functions of controlling risks. Consequently radiation effects might somewhat express the feature of biological risk controls. The shouldered survival of irradiated cells shows cybernetic characteristics that are assumed to be the mathematical foundation of controlling risks. The dose-response relationship shows another type of cybernetic characteristics, which could be reduced to the same basic form of controlling risks. The limited study of radiation effects definitely confirms the two

Preliminary early evaluation of radiation acute syndrome severity in an animal model

International Nuclear Information System (INIS)

Gimenez, J.C.; Nasazzi, N.B.; Taja, M.R.; Nagle, C.; Dubner, D.; Di Rizzio, C.

1992-01-01

To improve the knowledge of Radiation Acute Syndrome radiopathological picture, whole body x-rays irradiation at 2Gy of a primate (Cebus apella paraguayanus) used as model has been performed. Early evaluations of clinical symptoms and dose and damage biological indicators have shown that this primate has given out similar responses to those of man. (author)

Preliminary early evaluation of radiation acute syndrome severity in an animal model

Energy Technology Data Exchange (ETDEWEB)

Gimenez, J.C.; Nasazzi, N.B.; Taja, M.R. [Comision Nacional de Energia Atomica, (Argentina); Nagle, C. [Centro de Educacion Medica e Investigaciones Clinicas (Argentina); Dubner, D. [Comision Nacional de Energia Atomica, (Argentina); Di Rizzio, C. [Academia Nacional de Medicina (Argentina)

1992-07-01

To improve the knowledge of Radiation Acute Syndrome radiopathological picture, whole body x-rays irradiation at 2Gy of a primate (Cebus apella paraguayanus) used as model has been performed. Early evaluations of clinical symptoms and dose and damage biological indicators have shown that this primate has given out similar responses to those of man. (author)

Health consequences of ionizing radiation exposure

International Nuclear Information System (INIS)

Dalci, D.; Dorter, G.; Guclu, I.

2004-01-01

The increasing use of ionizing radiations all over the world induces an ever increasing interest of the professionals as well as of the whole society in health protection and the risk due to these practices. Shortly after its discovery, it was recognized that ionizing radiation can have adverse health effects and knowledge of its detrimental effects has accumulated. The fact that ionizing radiation produces biological damage has been known for many years. The biological effects of ionizing radiation for radiation protection considerations are grouped into two categories: The deterministic and the stochastic ones. Deterministic radiation effects can be clinically diagnosed in the exposed individual and occur when above a certain 'threshold' an appropriately high dose is absorbed in the tissues and organs to cause the death of a large number of cells and consequently to impair tissue or organ functions early after exposure. A clinically observable biological effect (Acute Radiation Syndromes, ARS) that occurs days to months after an acute radiation dose. ARS is a complex of acute injury manifestations that occur after a sufficiently large portion of a person's body is exposed to a high dose of ionizing radiation. Such irradiation initially injures all organs to some extent, but the timing and extent of the injury manifestations depend upon the type, rate, and dose of radiation received. Stochastic radiation effects are the chronic effects of radiation result from relatively low exposure levels delivered over long periods of time. These are sort of effects that might result from occupational exposure, or to the background exposure levels (includes radioactive pollution). Such late effects might be the development of malignant (cancerous) disease and of the hereditary consequences. These effects may be observed many years after the radiation exposure. There is a latent period between the initial radiation exposure and the development of the biological effect. In this

Patent foramen ovale increases the risk of acute ischemic stroke in patients with acute pulmonary embolism leading to right ventricular dysfunction.

Science.gov (United States)

Goliszek, Sylwia; Wiśniewska, Małgorzata; Kurnicka, Katarzyna; Lichodziejewska, Barbara; Ciurzyński, Michał; Kostrubiec, Maciej; Gołębiowski, Marek; Babiuch, Marek; Paczynska, Marzanna; Koć, Marcin; Palczewski, Piotr; Wyzgał, Anna; Pruszczyk, Piotr

2014-11-01

Patent foramen ovale (PFO) is an established risk factor for ischemic stroke. Since acute right ventricular dysfunction (RVD) observed in patients with PE can lead to right-to-left inter-atrial shunt via PFO, we hypothesized that PFO is a risk factor for ischemic stroke in PE with significant right ventricular dysfunction. 55 patients (31 F, 24M), median age 49 years (range 19-83 years) with confirmed PE underwent echocardiography for RVD and PFO assessment. High risk acute PE was diagnosed in 3 (5.5%) patients, while 16 (29%) hemodynamically stable with RVD patients formed a group with intermediate-risk PE. PFO was diagnosed in 19 patients (34.5%). Diffusion-weighted MRI of the brain for acute ischemic stroke (AIS) was performed in all patients 4.91 ± 4.1 days after admission. AIS was detected by MRI in 4 patients (7.3%). Only one stroke was clinically overt and resulted in hemiplegia. All 4 AIS occurred in the PFO positive group (4 of 19 patients), and none in subjects without PFO (21.0% vs 0%, p=0.02). Moreover, all AIS occurred in patients with RVD and PFO, and none in patients with PFO without RVD (50% vs 0%, p=0.038). Our data suggest that acute pulmonary embolism resulting in right ventricular dysfunction may lead to acute ischemic stroke in patients with patent foramen ovale. However, the clinical significance of such lesions remains to be determined. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interaction of radiation, Dihydroxyanthraquinone, and Adriamycin on the induction of acute lethality in mice

International Nuclear Information System (INIS)

Kimler, B.F.; Cox, G.G.; Reddy, E.K.

1984-01-01

The acute lethality induced by combinations of radiation, Dihydroxyanthraquinone (DHAQ), and Adriamycin (ADR) was investigated in mice. Whole-body irradiation produced acute lethality, with an LD-50/30 of approximately 6.5 Gy. ADR and DHAQ produced LD-50/30's of 14 and 4 mg/kg, respectively. When 10 mg/kg doses were fractionated into 5 x 2 mg/kg daily doses, both drugs were equally or more efficient at producing mortality, 90% by day 30. When 4 Gy radiation was combined with 5 mg/kg ADR or 5 mg/kg DHAQ, a response no greater than that produced by drug alone was obtained. However, when 5 mg/kg ADR was administered concomitantly with 5 mg/kg DHAQ, there was a less-than-additive induction of lethality, resulting in only 21% mortality by day 20. ADR and DHAQ (at doses of 5 mg/kg) were combined but with a 1 day interval between drugs, the protective effect was lost and animals died earlier than after either agent alone. At present, no definite explanation is available for this unusual protective effect of ADR against acute lethality induced by DHAQ

Ionizing radiation and genetic risks

International Nuclear Information System (INIS)

Sankaranarayanan, K.; Wassom, J.S.

2005-01-01

Recent estimates of genetic risks from exposure of human populations to ionizing radiation are those presented in the 2001 report of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). These estimates incorporate two important concepts, namely, the following: (1) most radiation-induced mutations are DNA deletions, often encompassing multiple genes, but only a small proportion of the induced deletions is compatible with offspring viability; and (2) the viability-compatible deletions induced in germ cells are more likely to manifest themselves as multi-system developmental anomalies rather than as single gene disorders. This paper: (a) pursues these concepts further in the light of knowledge of mechanisms of origin of deletions and other rearrangements from two fields of contemporary research: repair of radiation-induced DNA double-strand breaks (DSBs) in mammalian somatic cells and human molecular genetics; and (b) extends them to deletions induced in the germ cell stages of importance for radiation risk estimation, namely, stem cell spermatogonia in males and oocytes in females. DSB repair studies in somatic cells have elucidated the roles of two mechanistically distinct pathways, namely, homologous recombination repair (HRR) that utilizes extensive sequence homology and non-homologous end-joining (NHEJ) that requires little or no homology at the junctions. A third process, single-strand annealing (SSA), which utilizes short direct repeat sequences, is considered a variant of HRR. HRR is most efficient in late S and G 2 phases of the cell cycle and is a high fidelity mechanism. NHEJ operates in all cell cycle phases, but is especially important in G 1 . In the context of radiation-induced DSBs, NHEJ is error-prone. SSA is also an error-prone mechanism and its role is presumably similar to that of HRR. Studies in human molecular genetics have demonstrated that the occurrence of large deletions, duplications or other rearrangements

Ionizing radiation and genetic risks

Energy Technology Data Exchange (ETDEWEB)

Sankaranarayanan, K. [Department of Toxicogenetics, Leiden University Medical Centre, Sylvius Laboratories, Wassenaarseweg 72, 2333 AL Leiden (Netherlands)]. E-mail: sankaran@lumc.nl; Wassom, J.S. [YAHSGS, LLC, Richland, WA 99352 (United States); Life Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 (United States)

2005-10-15

Recent estimates of genetic risks from exposure of human populations to ionizing radiation are those presented in the 2001 report of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). These estimates incorporate two important concepts, namely, the following: (1) most radiation-induced mutations are DNA deletions, often encompassing multiple genes, but only a small proportion of the induced deletions is compatible with offspring viability; and (2) the viability-compatible deletions induced in germ cells are more likely to manifest themselves as multi-system developmental anomalies rather than as single gene disorders. This paper: (a) pursues these concepts further in the light of knowledge of mechanisms of origin of deletions and other rearrangements from two fields of contemporary research: repair of radiation-induced DNA double-strand breaks (DSBs) in mammalian somatic cells and human molecular genetics; and (b) extends them to deletions induced in the germ cell stages of importance for radiation risk estimation, namely, stem cell spermatogonia in males and oocytes in females. DSB repair studies in somatic cells have elucidated the roles of two mechanistically distinct pathways, namely, homologous recombination repair (HRR) that utilizes extensive sequence homology and non-homologous end-joining (NHEJ) that requires little or no homology at the junctions. A third process, single-strand annealing (SSA), which utilizes short direct repeat sequences, is considered a variant of HRR. HRR is most efficient in late S and G{sub 2} phases of the cell cycle and is a high fidelity mechanism. NHEJ operates in all cell cycle phases, but is especially important in G{sub 1}. In the context of radiation-induced DSBs, NHEJ is error-prone. SSA is also an error-prone mechanism and its role is presumably similar to that of HRR. Studies in human molecular genetics have demonstrated that the occurrence of large deletions, duplications or other

Radiation risks and benefits: politics and morality

International Nuclear Information System (INIS)

Maxey, M.N.

1983-01-01

The bioethical framework from which moral reasoning concerning nuclear technology has been derived is both seriously flawed and conceptually inadequate. The reasons are examined and are arranged in response to three questions. First, what is the status of alleged scientific evidence from which moral conclusions about the unacceptability of man-made radiation exposures are derived. Secondly, what criticisms of risk assessment reasoning are pertinent to ethical reflection. Finally, what revisions in an ethical framework are necessary if risk estimates of low-dose radiation exposure are to be conducted properly

Granulocyte Colony-Stimulating Factor in the Treatment of Acute Radiation Syndrome: A Concise Review

Directory of Open Access Journals (Sweden)

Michal Hofer

2014-04-01

Full Text Available This article concisely summarizes data on the action of one of the principal and best known growth factors, the granulocyte colony-stimulating factor (G-CSF, in a mammalian organism exposed to radiation doses inducing acute radiation syndrome. Highlighted are the topics of its real or anticipated use in radiation accident victims, the timing of its administration, the possibilities of combining G-CSF with other drugs, the ability of other agents to stimulate endogenous G-CSF production, as well as of the capability of this growth factor to ameliorate not only the bone marrow radiation syndrome but also the gastrointestinal radiation syndrome. G-CSF is one of the pivotal drugs in the treatment of radiation accident victims and its employment in this indication can be expected to remain or even grow in the future.

Acute respiratory failure in Pakistani patients: risk factors associated with mortality

International Nuclear Information System (INIS)

Hussain, S.F.; Irfan, M.; Naqi, Y.S.; Islam, M.; Akhtar, W.

2006-01-01

Objective: To assess the outcome and risk factors associated with mortality in patients with acute respiratory failure (ARF). Design: Observational study. Place and Duration of Study: The Aga Khan University Hospital, Karachi, between January 1997 and June 2001. Patients and Methods: All adult patients admitted with a medical cause of acute respiratory failure were reviewed. The primary outcome measure was mortality and secondary outcome measures were factors associated with mortality in ARF. Multiple logistic regression analysis was used to identify the independent risk factors for mortality. Results: A total of 270 patients were admitted with ARF. Hypercapnic respiratory failure was seen in 186 (69%) and hypoxemic in 84 (31%) cases. Pneumonia and COPD exacerbation were the most common underlying causes of ARF. Ventilator support was required in 93 (34.4%) patients. Hospital mortality was 28%. Chronic renal failure, malignancy, hypokalemia, severe acidosis (pH <7.25), septicemia and ARDS independently correlated with mortality. Mortality rate increased sharply (84%) with the presence of three or more risk factors. Conclusion: Acute respiratory failure has a high mortality rate (28%). Development of ARDS or septicemia was associated with high mortality. Presence of more than one risk factor significantly increased the mortality rate. (author)

Mammography and radiation risk; Mammographie und Strahlenrisiko

Energy Technology Data Exchange (ETDEWEB)

Jung, H. [Hamburg Univ. (Germany). Inst. fuer Biophysik und Strahlenbiologie

1998-10-01

Breast cancer is the most frequent malignant neoplasia among women in Germany. The use of mammography as the most relevant diagnostic procedure has increased rapidly over the last decade. Radiation risks associated with mammography may be estimated from the results of numerous epidemiological studies providing risk coefficients for breast cancer in relation to age at exposure. Various calculations can be performed using the risk coefficients. For instance, a single mammography examination (bilateral, two views of each breast) of a women aged 45 may enhance the risk of developing breast cancer during her lifetime numerically from about 12% of 12.0036%. This increase in risk is lower by a factor of 3,300 as compared to the risk of developing breast cancer in the absence of radiation exposure. At the age of 40 or more, the benefit of mammography exceeds the radiation risk by a factor of about 100. At higher ages this factor increases further. Finally, the dualism of individual risk and collective risk is considered. It is shown that the individual risk of a patient, even after multiple mammography examinations, is vanishingly small. Nevertheless, the basic principle of minimising radiation exposure must be followed to keep the collective risk in the total population as low as reasonably achievable. (orig.) [Deutsch] Das Mammakarzinom ist in Deutschland die haeufigste Krebserkrankung der Frau, und entsprechend oft wird die Mammographie als das derzeit wichtigste Diagnoseverfahren eingesetzt. Zur Beurteilung des mit einer mammographischen Untersuchung verbundenen Strahlenrisikos liegen die Resultate einer groesseren Anzahl strahlenepidemiologischer Studien vor. Diese liefern den Risikokoeffizienten fuer Brustkrebs in Abhaengigkeit vom Lebensalter bei Strahlenexposition und ermoeglichen somit die Berechnung des altersabhaengigen Strahlenrisikos. Beispielsweise wird durch eine einmalige Mammographie-Untersuchung (bilateral, je zwei Aufnahmen in zwei Ebenen) bei einer 45

Cancer risk of patients discharged with acute myocardial infarct

DEFF Research Database (Denmark)

Dreyer, L; Olsen, J H

1998-01-01

We studied whether common shared environmental or behavioral risk factors, other than tobacco smoking, underlie both atherosclerotic diseases and cancer. We identified a group of 96,891 one-year survivors of acute myocardial infarct through the Danish Hospital Discharge Register between 1977...... and 1989. We calculated the incidence of cancer in this group by linking it to the Danish Cancer Registry for the period 1978-1993. There was no consistent excess over the expected figures for any of the categories of cancer not related to tobacco smoking. Specifically, the rates of colorectal cancer...... in acute myocardial infarct patients were similar to those of the general population, as were the rates for hormone-related cancers, including endometrial and postmenopausal breast cancers. We found a moderate increase in the risk for tobacco-related cancers, which was strongest for patients with early...

High-risk carotid plaques identified by CT-angiogram can predict acute myocardial infarction.

Science.gov (United States)

Mosleh, Wassim; Adib, Keenan; Natdanai, Punnanithinont; Carmona-Rubio, Andres; Karki, Roshan; Paily, Jacienta; Ahmed, Mohamed Abdel-Aal; Vakkalanka, Sujit; Madam, Narasa; Gudleski, Gregory D; Chung, Charles; Sharma, Umesh C

2017-04-01

Prior studies identified the incremental value of non-invasive imaging by CT-angiogram (CTA) to detect high-risk coronary atherosclerotic plaques. Due to their superficial locations, larger calibers and motion-free imaging, the carotid arteries provide the best anatomic access for the non-invasive characterization of atherosclerotic plaques. We aim to assess the ability of predicting obstructive coronary artery disease (CAD) or acute myocardial infarction (MI) based on high-risk carotid plaque features identified by CTA. We retrospectively examined carotid CTAs of 492 patients that presented with acute stroke to characterize the atherosclerotic plaques of the carotid arteries and examined development of acute MI and obstructive CAD within 12-months. Carotid lesions were defined in terms of calcifications (large or speckled), presence of low-attenuation plaques, positive remodeling, and presence of napkin ring sign. Adjusted relative risks were calculated for each plaque features. Patients with speckled (<3 mm) calcifications and/or larger calcifications on CTA had a higher risk of developing an MI and/or obstructive CAD within 1 year compared to patients without (adjusted RR of 7.51, 95%CI 1.26-73.42, P = 0.001). Patients with low-attenuation plaques on CTA had a higher risk of developing an MI and/or obstructive CAD within 1 year than patients without (adjusted RR of 2.73, 95%CI 1.19-8.50, P = 0.021). Presence of carotid calcifications and low-attenuation plaques also portended higher sensitivity (100 and 79.17%, respectively) for the development of acute MI. Presence of carotid calcifications and low-attenuation plaques can predict the risk of developing acute MI and/or obstructive CAD within 12-months. Given their high sensitivity, their absence can reliably exclude 12-month events.

Acute radiation syndrome (ARS – treatment of the reduced host defense

Directory of Open Access Journals (Sweden)

Heslet L

2012-01-01

Full Text Available Lars Heslet1, Christiane Bay2, Steen Nepper-Christensen31Serendex ApS, Gentofte; 2University of Copenhagen, Medical Faculty, Copenhagen; 3Department of Head and Neck Surgery, Otorhinolaryngology, Køge University Hospital, Køge, DenmarkBackground: The current radiation threat from the Fukushima power plant accident has prompted rethinking of the contingency plan for prophylaxis and treatment of the acute radiation syndrome (ARS. The well-documented effect of the growth factors (granulocyte colony-stimulating factor [G-CSF] and granulocyte-macrophage colony-stimulating factor [GM-CSF] in acute radiation injury has become standard treatment for ARS in the United States, based on the fact that growth factors increase number and functions of both macrophages and granulocytes.Methods: Review of the current literature.Results: The lungs have their own host defense system, based on alveolar macrophages. After radiation exposure to the lungs, resting macrophages can no longer be transformed, not even during systemic administration of growth factors because G-CSF/GM-CSF does not penetrate the alveoli. Under normal circumstances, locally-produced GM-CSF receptors transform resting macrophages into fully immunocompetent dendritic cells in the sealed-off pulmonary compartment. However, GM-CSF is not expressed in radiation injured tissue due to defervescence of the macrophages. In order to maintain the macrophage’s important role in host defense after radiation exposure, it is hypothesized that it is necessary to administer the drug exogenously in order to uphold the barrier against exogenous and endogenous infections and possibly prevent the potentially lethal systemic infection, which is the main cause of death in ARS.Recommendation: Preemptive treatment should be initiated after suspected exposure of a radiation dose of at least ~2 Gy by prompt dosing of 250–400 µg GM-CSF/m2 or 5 µg/kg G-CSF administered systemically and concomitant inhalation of

Methodology in use for the assessment of carcinogenic risk. II. Radiation. Oncology overview

International Nuclear Information System (INIS)

1983-04-01

Oncology Overviews are a service of the International Cancer Research Data Bank (ICRDB) Program of the National Cancer Institute, intended to facilitate and promote the exchange of information between cancer scientists by keeping them aware of literature related to their research being published by other laboratories throughout the world. Each Oncology Overview represents a survey of the literature associated with a selected area of cancer research. It contains abstracts of articles which have been selected and organized by researchers associated with the field. Contents: Assessment of carcinogenic risk from environmental and occupational exposures to ionizing radiation; Assessment of carcinogenic risk from exposure to ionizing radiation used for medical diagnosis or treatment; Assessment of carcinogenic risk from exposure to ionizing radiation following nuclear bomb explosions; Comparison of risk from radiation sources with risk from nonradiation sources; Experimental studies to assess risk of carcinogenesis following exposure to ionizing radiation; Theoretical aspects of dose-response relationships in the assessment of carcinogenic risk from exposure to ionizing radiation; Public policy and standards for acceptable risk from exposure to ionizing radiation; General reviews on the assessment of risk from exposure to ionizing radiation

Radiation induced liver disease: A clinical update